[asterisk/asterisk.git] / main / rtp.c

/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2006, Digium, Inc.
 *
 * Mark Spencer <markster@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*! 
 * \file 
 *
 * \brief Supports RTP and RTCP with Symmetric RTP support for NAT traversal.
 *
 * \author Mark Spencer <markster@digium.com>
 * 
 * \note RTP is defined in RFC 3550.
 */

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision$")

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <signal.h>
#include <errno.h>
#include <unistd.h>
#include <netinet/in.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <fcntl.h>

#include "asterisk/rtp.h"
#include "asterisk/frame.h"
#include "asterisk/logger.h"
#include "asterisk/options.h"
#include "asterisk/channel.h"
#include "asterisk/acl.h"
#include "asterisk/channel.h"
#include "asterisk/config.h"
#include "asterisk/lock.h"
#include "asterisk/utils.h"
#include "asterisk/netsock.h"
#include "asterisk/cli.h"
#include "asterisk/manager.h"
#include "asterisk/unaligned.h"
#include "asterisk/utils.h"

#define MAX_TIMESTAMP_SKEW      640

#define RTP_SEQ_MOD     (1<<16)         /*!< A sequence number can't be more than 16 bits */
#define RTCP_DEFAULT_INTERVALMS   5000  /*!< Default milli-seconds between RTCP reports we send */
#define RTCP_MIN_INTERVALMS       500   /*!< Min milli-seconds between RTCP reports we send */
#define RTCP_MAX_INTERVALMS       60000 /*!< Max milli-seconds between RTCP reports we send */

#define RTCP_PT_FUR     192
#define RTCP_PT_SR      200
#define RTCP_PT_RR      201
#define RTCP_PT_SDES    202
#define RTCP_PT_BYE     203
#define RTCP_PT_APP     204

#define RTP_MTU         1200

#define DEFAULT_DTMF_TIMEOUT 3000       /*!< samples */

static int dtmftimeout = DEFAULT_DTMF_TIMEOUT;

static int rtpstart;                    /*!< First port for RTP sessions (set in rtp.conf) */
static int rtpend;                      /*!< Last port for RTP sessions (set in rtp.conf) */
static int rtpdebug;                    /*!< Are we debugging? */
static int rtcpdebug;                   /*!< Are we debugging RTCP? */
static int rtcpstats;                   /*!< Are we debugging RTCP? */
static int rtcpinterval = RTCP_DEFAULT_INTERVALMS; /*!< Time between rtcp reports in millisecs */
static int stundebug;                   /*!< Are we debugging stun? */
static struct sockaddr_in rtpdebugaddr; /*!< Debug packets to/from this host */
static struct sockaddr_in rtcpdebugaddr;        /*!< Debug RTCP packets to/from this host */
#ifdef SO_NO_CHECK
static int nochecksums;
#endif

/* Uncomment this to enable more intense native bridging, but note: this is currently buggy */
/* #define P2P_INTENSE */

/*!
 * \brief Structure representing a RTP session.
 *
 * RTP session is defined on page 9 of RFC 3550: "An association among a set of participants communicating with RTP.  A participant may be involved in multiple RTP sessions at the same time [...]"
 *
 */
/*! \brief The value of each payload format mapping: */
struct rtpPayloadType {
        int isAstFormat;        /*!< whether the following code is an AST_FORMAT */
        int code;
};


/*! \brief RTP session description */
struct ast_rtp {
        int s;
        struct ast_frame f;
        unsigned char rawdata[8192 + AST_FRIENDLY_OFFSET];
        unsigned int ssrc;              /*!< Synchronization source, RFC 3550, page 10. */
        unsigned int themssrc;          /*!< Their SSRC */
        unsigned int rxssrc;
        unsigned int lastts;
        unsigned int lastrxts;
        unsigned int lastividtimestamp;
        unsigned int lastovidtimestamp;
        unsigned int lastitexttimestamp;
        unsigned int lastotexttimestamp;
        unsigned int lasteventseqn;
        int lastrxseqno;                /*!< Last received sequence number */
        unsigned short seedrxseqno;     /*!< What sequence number did they start with?*/
        unsigned int seedrxts;          /*!< What RTP timestamp did they start with? */
        unsigned int rxcount;           /*!< How many packets have we received? */
        unsigned int rxoctetcount;      /*!< How many octets have we received? should be rxcount *160*/
        unsigned int txcount;           /*!< How many packets have we sent? */
        unsigned int txoctetcount;      /*!< How many octets have we sent? (txcount*160)*/
        unsigned int cycles;            /*!< Shifted count of sequence number cycles */
        double rxjitter;                /*!< Interarrival jitter at the moment */
        double rxtransit;               /*!< Relative transit time for previous packet */
        int lasttxformat;
        int lastrxformat;

        int rtptimeout;                 /*!< RTP timeout time (negative or zero means disabled, negative value means temporarily disabled) */
        int rtpholdtimeout;             /*!< RTP timeout when on hold (negative or zero means disabled, negative value means temporarily disabled). */
        int rtpkeepalive;               /*!< Send RTP comfort noice packets for keepalive */

        /* DTMF Reception Variables */
        char resp;
        unsigned int lastevent;
        int dtmfcount;
        unsigned int dtmfsamples;
        /* DTMF Transmission Variables */
        unsigned int lastdigitts;
        char sending_digit;     /*!< boolean - are we sending digits */
        char send_digit;        /*!< digit we are sending */
        int send_payload;
        int send_duration;
        int nat;
        unsigned int flags;
        struct sockaddr_in us;          /*!< Socket representation of the local endpoint. */
        struct sockaddr_in them;        /*!< Socket representation of the remote endpoint. */
        struct timeval rxcore;
        struct timeval txcore;
        double drxcore;                 /*!< The double representation of the first received packet */
        struct timeval lastrx;          /*!< timeval when we last received a packet */
        struct timeval dtmfmute;
        struct ast_smoother *smoother;
        int *ioid;
        unsigned short seqno;           /*!< Sequence number, RFC 3550, page 13. */
        unsigned short rxseqno;
        struct sched_context *sched;
        struct io_context *io;
        void *data;
        ast_rtp_callback callback;
#ifdef P2P_INTENSE
        ast_mutex_t bridge_lock;
#endif
        struct rtpPayloadType current_RTP_PT[MAX_RTP_PT];
        int rtp_lookup_code_cache_isAstFormat; /*!< a cache for the result of rtp_lookup_code(): */
        int rtp_lookup_code_cache_code;
        int rtp_lookup_code_cache_result;
        struct ast_rtcp *rtcp;
        struct ast_codec_pref pref;
        struct ast_rtp *bridged;        /*!< Who we are Packet bridged to */
};

/* Forward declarations */
static int ast_rtcp_write(const void *data);
static void timeval2ntp(struct timeval tv, unsigned int *msw, unsigned int *lsw);
static int ast_rtcp_write_sr(const void *data);
static int ast_rtcp_write_rr(const void *data);
static unsigned int ast_rtcp_calc_interval(struct ast_rtp *rtp);
static int ast_rtp_senddigit_continuation(struct ast_rtp *rtp);
int ast_rtp_senddigit_end(struct ast_rtp *rtp, char digit);

#define FLAG_3389_WARNING               (1 << 0)
#define FLAG_NAT_ACTIVE                 (3 << 1)
#define FLAG_NAT_INACTIVE               (0 << 1)
#define FLAG_NAT_INACTIVE_NOWARN        (1 << 1)
#define FLAG_HAS_DTMF                   (1 << 3)
#define FLAG_P2P_SENT_MARK              (1 << 4)
#define FLAG_P2P_NEED_DTMF              (1 << 5)
#define FLAG_CALLBACK_MODE              (1 << 6)
#define FLAG_DTMF_COMPENSATE            (1 << 7)
#define FLAG_HAS_STUN                   (1 << 8)

/*!
 * \brief Structure defining an RTCP session.
 * 
 * The concept "RTCP session" is not defined in RFC 3550, but since 
 * this structure is analogous to ast_rtp, which tracks a RTP session, 
 * it is logical to think of this as a RTCP session.
 *
 * RTCP packet is defined on page 9 of RFC 3550.
 * 
 */
struct ast_rtcp {
        int s;                          /*!< Socket */
        struct sockaddr_in us;          /*!< Socket representation of the local endpoint. */
        struct sockaddr_in them;        /*!< Socket representation of the remote endpoint. */
        unsigned int soc;               /*!< What they told us */
        unsigned int spc;               /*!< What they told us */
        unsigned int themrxlsr;         /*!< The middle 32 bits of the NTP timestamp in the last received SR*/
        struct timeval rxlsr;           /*!< Time when we got their last SR */
        struct timeval txlsr;           /*!< Time when we sent or last SR*/
        unsigned int expected_prior;    /*!< no. packets in previous interval */
        unsigned int received_prior;    /*!< no. packets received in previous interval */
        int schedid;                    /*!< Schedid returned from ast_sched_add() to schedule RTCP-transmissions*/
        unsigned int rr_count;          /*!< number of RRs we've sent, not including report blocks in SR's */
        unsigned int sr_count;          /*!< number of SRs we've sent */
        unsigned int lastsrtxcount;     /*!< Transmit packet count when last SR sent */
        double accumulated_transit;     /*!< accumulated a-dlsr-lsr */
        double rtt;                     /*!< Last reported rtt */
        unsigned int reported_jitter;   /*!< The contents of their last jitter entry in the RR */
        unsigned int reported_lost;     /*!< Reported lost packets in their RR */
        char quality[AST_MAX_USER_FIELD];
        double maxrxjitter;
        double minrxjitter;
        double maxrtt;
        double minrtt;
        int sendfur;
};

/*!
 * \brief STUN support code
 *
 * This code provides some support for doing STUN transactions.
 * Eventually it should be moved elsewhere as other protocols
 * than RTP can benefit from it - e.g. SIP.
 * STUN is described in RFC3489 and it is based on the exchange
 * of UDP packets between a client and one or more servers to
 * determine the externally visible address (and port) of the client
 * once it has gone through the NAT boxes that connect it to the
 * outside.
 * The simplest request packet is just the header defined in
 * struct stun_header, and from the response we may just look at
 * one attribute, STUN_MAPPED_ADDRESS, that we find in the response.
 * By doing more transactions with different server addresses we
 * may determine more about the behaviour of the NAT boxes, of
 * course - the details are in the RFC.
 *
 * All STUN packets start with a simple header made of a type,
 * length (excluding the header) and a 16-byte random transaction id.
 * Following the header we may have zero or more attributes, each
 * structured as a type, length and a value (whose format depends
 * on the type, but often contains addresses).
 * Of course all fields are in network format.
 */

typedef struct { unsigned int id[4]; } __attribute__((packed)) stun_trans_id;

struct stun_header {
        unsigned short msgtype;
        unsigned short msglen;
        stun_trans_id  id;
        unsigned char ies[0];
} __attribute__((packed));

struct stun_attr {
        unsigned short attr;
        unsigned short len;
        unsigned char value[0];
} __attribute__((packed));

/*
 * The format normally used for addresses carried by STUN messages.
 */
struct stun_addr {
        unsigned char unused;
        unsigned char family;
        unsigned short port;
        unsigned int addr;
} __attribute__((packed));

#define STUN_IGNORE             (0)
#define STUN_ACCEPT             (1)

/*! \brief STUN message types
 * 'BIND' refers to transactions used to determine the externally
 * visible addresses. 'SEC' refers to transactions used to establish
 * a session key for subsequent requests.
 * 'SEC' functionality is not supported here.
 */
 
#define STUN_BINDREQ    0x0001
#define STUN_BINDRESP   0x0101
#define STUN_BINDERR    0x0111
#define STUN_SECREQ     0x0002
#define STUN_SECRESP    0x0102
#define STUN_SECERR     0x0112

/*! \brief Basic attribute types in stun messages.
 * Messages can also contain custom attributes (codes above 0x7fff)
 */
#define STUN_MAPPED_ADDRESS     0x0001
#define STUN_RESPONSE_ADDRESS   0x0002
#define STUN_CHANGE_REQUEST     0x0003
#define STUN_SOURCE_ADDRESS     0x0004
#define STUN_CHANGED_ADDRESS    0x0005
#define STUN_USERNAME           0x0006
#define STUN_PASSWORD           0x0007
#define STUN_MESSAGE_INTEGRITY  0x0008
#define STUN_ERROR_CODE         0x0009
#define STUN_UNKNOWN_ATTRIBUTES 0x000a
#define STUN_REFLECTED_FROM     0x000b

/*! \brief helper function to print message names */
static const char *stun_msg2str(int msg)
{
        switch (msg) {
        case STUN_BINDREQ:
                return "Binding Request";
        case STUN_BINDRESP:
                return "Binding Response";
        case STUN_BINDERR:
                return "Binding Error Response";
        case STUN_SECREQ:
                return "Shared Secret Request";
        case STUN_SECRESP:
                return "Shared Secret Response";
        case STUN_SECERR:
                return "Shared Secret Error Response";
        }
        return "Non-RFC3489 Message";
}

/*! \brief helper function to print attribute names */
static const char *stun_attr2str(int msg)
{
        switch (msg) {
        case STUN_MAPPED_ADDRESS:
                return "Mapped Address";
        case STUN_RESPONSE_ADDRESS:
                return "Response Address";
        case STUN_CHANGE_REQUEST:
                return "Change Request";
        case STUN_SOURCE_ADDRESS:
                return "Source Address";
        case STUN_CHANGED_ADDRESS:
                return "Changed Address";
        case STUN_USERNAME:
                return "Username";
        case STUN_PASSWORD:
                return "Password";
        case STUN_MESSAGE_INTEGRITY:
                return "Message Integrity";
        case STUN_ERROR_CODE:
                return "Error Code";
        case STUN_UNKNOWN_ATTRIBUTES:
                return "Unknown Attributes";
        case STUN_REFLECTED_FROM:
                return "Reflected From";
        }
        return "Non-RFC3489 Attribute";
}

/*! \brief here we store credentials extracted from a message */
struct stun_state {
        const char *username;
        const char *password;
};

static int stun_process_attr(struct stun_state *state, struct stun_attr *attr)
{
        if (stundebug)
                ast_verbose("Found STUN Attribute %s (%04x), length %d\n",
                            stun_attr2str(ntohs(attr->attr)), ntohs(attr->attr), ntohs(attr->len));
        switch (ntohs(attr->attr)) {
        case STUN_USERNAME:
                state->username = (const char *) (attr->value);
                break;
        case STUN_PASSWORD:
                state->password = (const char *) (attr->value);
                break;
        default:
                if (stundebug)
                        ast_verbose("Ignoring STUN attribute %s (%04x), length %d\n", 
                                    stun_attr2str(ntohs(attr->attr)), ntohs(attr->attr), ntohs(attr->len));
        }
        return 0;
}

/*! \brief append a string to an STUN message */
static void append_attr_string(struct stun_attr **attr, int attrval, const char *s, int *len, int *left)
{
        int size = sizeof(**attr) + strlen(s);
        if (*left > size) {
                (*attr)->attr = htons(attrval);
                (*attr)->len = htons(strlen(s));
                memcpy((*attr)->value, s, strlen(s));
                (*attr) = (struct stun_attr *)((*attr)->value + strlen(s));
                *len += size;
                *left -= size;
        }
}

/*! \brief append an address to an STUN message */
static void append_attr_address(struct stun_attr **attr, int attrval, struct sockaddr_in *sin, int *len, int *left)
{
        int size = sizeof(**attr) + 8;
        struct stun_addr *addr;
        if (*left > size) {
                (*attr)->attr = htons(attrval);
                (*attr)->len = htons(8);
                addr = (struct stun_addr *)((*attr)->value);
                addr->unused = 0;
                addr->family = 0x01;
                addr->port = sin->sin_port;
                addr->addr = sin->sin_addr.s_addr;
                (*attr) = (struct stun_attr *)((*attr)->value + 8);
                *len += size;
                *left -= size;
        }
}

/*! \brief wrapper to send an STUN message */
static int stun_send(int s, struct sockaddr_in *dst, struct stun_header *resp)
{
        return sendto(s, resp, ntohs(resp->msglen) + sizeof(*resp), 0,
                      (struct sockaddr *)dst, sizeof(*dst));
}

/*! \brief helper function to generate a random request id */
static void stun_req_id(struct stun_header *req)
{
        int x;
        for (x = 0; x < 4; x++)
                req->id.id[x] = ast_random();
}

size_t ast_rtp_alloc_size(void)
{
        return sizeof(struct ast_rtp);
}

/*! \brief callback type to be invoked on stun responses. */
typedef int (stun_cb_f)(struct stun_attr *attr, void *arg);

/*! \brief handle an incoming STUN message.
 *
 * Do some basic sanity checks on packet size and content,
 * try to extract a bit of information, and possibly reply.
 * At the moment this only processes BIND requests, and returns
 * the externally visible address of the request.
 * If a callback is specified, invoke it with the attribute.
 */
static int stun_handle_packet(int s, struct sockaddr_in *src,
        unsigned char *data, size_t len, stun_cb_f *stun_cb, void *arg)
{
        struct stun_header *hdr = (struct stun_header *)data;
        struct stun_attr *attr;
        struct stun_state st;
        int ret = STUN_IGNORE;  
        int x;

        /* On entry, 'len' is the length of the udp payload. After the
         * initial checks it becomes the size of unprocessed options,
         * while 'data' is advanced accordingly.
         */
        if (len < sizeof(struct stun_header)) {
                ast_debug(1, "Runt STUN packet (only %d, wanting at least %d)\n", (int) len, (int) sizeof(struct stun_header));
                return -1;
        }
        len -= sizeof(struct stun_header);
        data += sizeof(struct stun_header);
        x = ntohs(hdr->msglen); /* len as advertised in the message */
        if (stundebug)
                ast_verbose("STUN Packet, msg %s (%04x), length: %d\n", stun_msg2str(ntohs(hdr->msgtype)), ntohs(hdr->msgtype), x);
        if (x > len) {
                ast_debug(1, "Scrambled STUN packet length (got %d, expecting %d)\n", x, (int)len);
        } else
                len = x;
        memset(&st, 0, sizeof(st));
        while (len) {
                if (len < sizeof(struct stun_attr)) {
                        ast_debug(1, "Runt Attribute (got %d, expecting %d)\n", (int)len, (int) sizeof(struct stun_attr));
                        break;
                }
                attr = (struct stun_attr *)data;
                /* compute total attribute length */
                x = ntohs(attr->len) + sizeof(struct stun_attr);
                if (x > len) {
                        ast_debug(1, "Inconsistent Attribute (length %d exceeds remaining msg len %d)\n", x, (int)len);
                        break;
                }
                if (stun_cb)
                        stun_cb(attr, arg);
                if (stun_process_attr(&st, attr)) {
                        ast_debug(1, "Failed to handle attribute %s (%04x)\n", stun_attr2str(ntohs(attr->attr)), ntohs(attr->attr));
                        break;
                }
                /* Clear attribute id: in case previous entry was a string,
                 * this will act as the terminator for the string.
                 */
                attr->attr = 0;
                data += x;
                len -= x;
        }
        /* Null terminate any string.
         * XXX NOTE, we write past the size of the buffer passed by the
         * caller, so this is potentially dangerous. The only thing that
         * saves us is that usually we read the incoming message in a
         * much larger buffer in the struct ast_rtp
         */
        *data = '\0';

        /* Now prepare to generate a reply, which at the moment is done
         * only for properly formed (len == 0) STUN_BINDREQ messages.
         */
        if (len == 0) {
                unsigned char respdata[1024];
                struct stun_header *resp = (struct stun_header *)respdata;
                int resplen = 0;        /* len excluding header */
                int respleft = sizeof(respdata) - sizeof(struct stun_header);

                resp->id = hdr->id;
                resp->msgtype = 0;
                resp->msglen = 0;
                attr = (struct stun_attr *)resp->ies;
                switch (ntohs(hdr->msgtype)) {
                case STUN_BINDREQ:
                        if (stundebug)
                                ast_verbose("STUN Bind Request, username: %s\n", 
                                            st.username ? st.username : "<none>");
                        if (st.username)
                                append_attr_string(&attr, STUN_USERNAME, st.username, &resplen, &respleft);
                        append_attr_address(&attr, STUN_MAPPED_ADDRESS, src, &resplen, &respleft);
                        resp->msglen = htons(resplen);
                        resp->msgtype = htons(STUN_BINDRESP);
                        stun_send(s, src, resp);
                        ret = STUN_ACCEPT;
                        break;
                default:
                        if (stundebug)
                                ast_verbose("Dunno what to do with STUN message %04x (%s)\n", ntohs(hdr->msgtype), stun_msg2str(ntohs(hdr->msgtype)));
                }
        }
        return ret;
}

/*! \brief Extract the STUN_MAPPED_ADDRESS from the stun response.
 * This is used as a callback for stun_handle_response
 * when called from ast_stun_request.
 */
static int stun_get_mapped(struct stun_attr *attr, void *arg)
{
        struct stun_addr *addr = (struct stun_addr *)(attr + 1);
        struct sockaddr_in *sa = (struct sockaddr_in *)arg;

        if (ntohs(attr->attr) != STUN_MAPPED_ADDRESS || ntohs(attr->len) != 8)
                return 1;       /* not us. */
        sa->sin_port = addr->port;
        sa->sin_addr.s_addr = addr->addr;
        return 0;
}

/*! \brief Generic STUN request
 * Send a generic stun request to the server specified,
 * possibly waiting for a reply and filling the 'reply' field with
 * the externally visible address. Note that in this case the request
 * will be blocking.
 * (Note, the interface may change slightly in the future).
 *
 * \param s the socket used to send the request
 * \param dst the address of the STUN server
 * \param username if non null, add the username in the request
 * \param answer if non null, the function waits for a response and
 *    puts here the externally visible address.
 * \return 0 on success, other values on error.
 */
int ast_stun_request(int s, struct sockaddr_in *dst,
        const char *username, struct sockaddr_in *answer)
{
        struct stun_header *req;
        unsigned char reqdata[1024];
        int reqlen, reqleft;
        struct stun_attr *attr;
        int res = 0;
        int retry;
        
        req = (struct stun_header *)reqdata;
        stun_req_id(req);
        reqlen = 0;
        reqleft = sizeof(reqdata) - sizeof(struct stun_header);
        req->msgtype = 0;
        req->msglen = 0;
        attr = (struct stun_attr *)req->ies;
        if (username)
                append_attr_string(&attr, STUN_USERNAME, username, &reqlen, &reqleft);
        req->msglen = htons(reqlen);
        req->msgtype = htons(STUN_BINDREQ);
        for (retry = 0; retry < 3; retry++) {   /* XXX make retries configurable */
                /* send request, possibly wait for reply */
                unsigned char reply_buf[1024];
                fd_set rfds;
                struct timeval to = { 3, 0 };   /* timeout, make it configurable */
                struct sockaddr_in src;
                socklen_t srclen;

                res = stun_send(s, dst, req);
                if (res < 0) {
                        ast_log(LOG_WARNING, "ast_stun_request send #%d failed error %d, retry\n",
                                retry, res);
                        continue;
                }
                if (answer == NULL)
                        break;
                FD_ZERO(&rfds);
                FD_SET(s, &rfds);
                res = ast_select(s + 1, &rfds, NULL, NULL, &to);
                if (res <= 0)   /* timeout or error */
                        continue;
                bzero(&src, sizeof(src));
                srclen = sizeof(src);
                /* XXX pass -1 in the size, because stun_handle_packet might
                 * write past the end of the buffer.
                 */
                res = recvfrom(s, reply_buf, sizeof(reply_buf) - 1,
                        0, (struct sockaddr *)&src, &srclen);
                if (res < 0) {
                        ast_log(LOG_WARNING, "ast_stun_request recvfrom #%d failed error %d, retry\n",
                                retry, res);
                        continue;
                }
                bzero(answer, sizeof(struct sockaddr_in));
                stun_handle_packet(s, &src, reply_buf, res,
                        stun_get_mapped, answer);
                res = 0; /* signal regular exit */
                break;
        }
        return res;
}

/*! \brief send a STUN BIND request to the given destination.
 * Optionally, add a username if specified.
 */
void ast_rtp_stun_request(struct ast_rtp *rtp, struct sockaddr_in *suggestion, const char *username)
{
        ast_stun_request(rtp->s, suggestion, username, NULL);
}

/*! \brief List of current sessions */
static AST_RWLIST_HEAD_STATIC(protos, ast_rtp_protocol);

static void timeval2ntp(struct timeval tv, unsigned int *msw, unsigned int *lsw)
{
        unsigned int sec, usec, frac;
        sec = tv.tv_sec + 2208988800u; /* Sec between 1900 and 1970 */
        usec = tv.tv_usec;
        frac = (usec << 12) + (usec << 8) - ((usec * 3650) >> 6);
        *msw = sec;
        *lsw = frac;
}

int ast_rtp_fd(struct ast_rtp *rtp)
{
        return rtp->s;
}

int ast_rtcp_fd(struct ast_rtp *rtp)
{
        if (rtp->rtcp)
                return rtp->rtcp->s;
        return -1;
}

unsigned int ast_rtcp_calc_interval(struct ast_rtp *rtp)
{
        unsigned int interval;
        /*! \todo XXX Do a more reasonable calculation on this one
         * Look in RFC 3550 Section A.7 for an example*/
        interval = rtcpinterval;
        return interval;
}

/* \brief Put RTP timeout timers on hold during another transaction, like T.38 */
void ast_rtp_set_rtptimers_onhold(struct ast_rtp *rtp)
{
        rtp->rtptimeout = (-1) * rtp->rtptimeout;
        rtp->rtpholdtimeout = (-1) * rtp->rtpholdtimeout;
}

/*! \brief Set rtp timeout */
void ast_rtp_set_rtptimeout(struct ast_rtp *rtp, int timeout)
{
        rtp->rtptimeout = timeout;
}

/*! \brief Set rtp hold timeout */
void ast_rtp_set_rtpholdtimeout(struct ast_rtp *rtp, int timeout)
{
        rtp->rtpholdtimeout = timeout;
}

/*! \brief set RTP keepalive interval */
void ast_rtp_set_rtpkeepalive(struct ast_rtp *rtp, int period)
{
        rtp->rtpkeepalive = period;
}

/*! \brief Get rtp timeout */
int ast_rtp_get_rtptimeout(struct ast_rtp *rtp)
{
        if (rtp->rtptimeout < 0)        /* We're not checking, but remembering the setting (during T.38 transmission) */
                return 0;
        return rtp->rtptimeout;
}

/*! \brief Get rtp hold timeout */
int ast_rtp_get_rtpholdtimeout(struct ast_rtp *rtp)
{
        if (rtp->rtptimeout < 0)        /* We're not checking, but remembering the setting (during T.38 transmission) */
                return 0;
        return rtp->rtpholdtimeout;
}

/*! \brief Get RTP keepalive interval */
int ast_rtp_get_rtpkeepalive(struct ast_rtp *rtp)
{
        return rtp->rtpkeepalive;
}

void ast_rtp_set_data(struct ast_rtp *rtp, void *data)
{
        rtp->data = data;
}

void ast_rtp_set_callback(struct ast_rtp *rtp, ast_rtp_callback callback)
{
        rtp->callback = callback;
}

void ast_rtp_setnat(struct ast_rtp *rtp, int nat)
{
        rtp->nat = nat;
}

int ast_rtp_getnat(struct ast_rtp *rtp)
{
        return ast_test_flag(rtp, FLAG_NAT_ACTIVE);
}

void ast_rtp_setdtmf(struct ast_rtp *rtp, int dtmf)
{
        ast_set2_flag(rtp, dtmf ? 1 : 0, FLAG_HAS_DTMF);
}

void ast_rtp_setdtmfcompensate(struct ast_rtp *rtp, int compensate)
{
        ast_set2_flag(rtp, compensate ? 1 : 0, FLAG_DTMF_COMPENSATE);
}

void ast_rtp_setstun(struct ast_rtp *rtp, int stun_enable)
{
        ast_set2_flag(rtp, stun_enable ? 1 : 0, FLAG_HAS_STUN);
}

static void rtp_bridge_lock(struct ast_rtp *rtp)
{
#ifdef P2P_INTENSE
        ast_mutex_lock(&rtp->bridge_lock);
#endif
        return;
}

static void rtp_bridge_unlock(struct ast_rtp *rtp)
{
#ifdef P2P_INTENSE
        ast_mutex_unlock(&rtp->bridge_lock);
#endif
        return;
}

static struct ast_frame *send_dtmf(struct ast_rtp *rtp, enum ast_frame_type type)
{
        if (((ast_test_flag(rtp, FLAG_DTMF_COMPENSATE) && type == AST_FRAME_DTMF_END) ||
             (type == AST_FRAME_DTMF_BEGIN)) && ast_tvcmp(ast_tvnow(), rtp->dtmfmute) < 0) {
                ast_debug(1, "Ignore potential DTMF echo from '%s'\n", ast_inet_ntoa(rtp->them.sin_addr));
                rtp->resp = 0;
                rtp->dtmfsamples = 0;
                return &ast_null_frame;
        }
        ast_debug(1, "Sending dtmf: %d (%c), at %s\n", rtp->resp, rtp->resp, ast_inet_ntoa(rtp->them.sin_addr));
        if (rtp->resp == 'X') {
                rtp->f.frametype = AST_FRAME_CONTROL;
                rtp->f.subclass = AST_CONTROL_FLASH;
        } else {
                rtp->f.frametype = type;
                rtp->f.subclass = rtp->resp;
        }
        rtp->f.datalen = 0;
        rtp->f.samples = 0;
        rtp->f.mallocd = 0;
        rtp->f.src = "RTP";
        return &rtp->f;
        
}

static inline int rtp_debug_test_addr(struct sockaddr_in *addr)
{
        if (rtpdebug == 0)
                return 0;
        if (rtpdebugaddr.sin_addr.s_addr) {
                if (((ntohs(rtpdebugaddr.sin_port) != 0)
                     && (rtpdebugaddr.sin_port != addr->sin_port))
                    || (rtpdebugaddr.sin_addr.s_addr != addr->sin_addr.s_addr))
                        return 0;
        }
        return 1;
}

static inline int rtcp_debug_test_addr(struct sockaddr_in *addr)
{
        if (rtcpdebug == 0)
                return 0;
        if (rtcpdebugaddr.sin_addr.s_addr) {
                if (((ntohs(rtcpdebugaddr.sin_port) != 0)
                     && (rtcpdebugaddr.sin_port != addr->sin_port))
                    || (rtcpdebugaddr.sin_addr.s_addr != addr->sin_addr.s_addr))
                        return 0;
        }
        return 1;
}


static struct ast_frame *process_cisco_dtmf(struct ast_rtp *rtp, unsigned char *data, int len)
{
        unsigned int event;
        char resp = 0;
        struct ast_frame *f = NULL;
        unsigned char seq;
        unsigned int flags;
        unsigned int power;

        /* We should have at least 4 bytes in RTP data */
        if (len < 4)
                return f;

        /*      The format of Cisco RTP DTMF packet looks like next:
                +0                              - sequence number of DTMF RTP packet (begins from 1,
                                                  wrapped to 0)
                +1                              - set of flags
                +1 (bit 0)              - flaps by different DTMF digits delimited by audio
                                                  or repeated digit without audio???
                +2 (+4,+6,...)  - power level? (rises from 0 to 32 at begin of tone
                                                  then falls to 0 at its end)
                +3 (+5,+7,...)  - detected DTMF digit (0..9,*,#,A-D,...)
                Repeated DTMF information (bytes 4/5, 6/7) is history shifted right
                by each new packet and thus provides some redudancy.
                
                Sample of Cisco RTP DTMF packet is (all data in hex):
                        19 07 00 02 12 02 20 02
                showing end of DTMF digit '2'.

                The packets
                        27 07 00 02 0A 02 20 02
                        28 06 20 02 00 02 0A 02
                shows begin of new digit '2' with very short pause (20 ms) after
                previous digit '2'. Bit +1.0 flips at begin of new digit.
                
                Cisco RTP DTMF packets comes as replacement of audio RTP packets
                so its uses the same sequencing and timestamping rules as replaced
                audio packets. Repeat interval of DTMF packets is 20 ms and not rely
                on audio framing parameters. Marker bit isn't used within stream of
                DTMFs nor audio stream coming immediately after DTMF stream. Timestamps
                are not sequential at borders between DTMF and audio streams,
        */

        seq = data[0];
        flags = data[1];
        power = data[2];
        event = data[3] & 0x1f;

        if (option_debug > 2 || rtpdebug)
                ast_debug(0, "Cisco DTMF Digit: %02x (len=%d, seq=%d, flags=%02x, power=%d, history count=%d)\n", event, len, seq, flags, power, (len - 4) / 2);
        if (event < 10) {
                resp = '0' + event;
        } else if (event < 11) {
                resp = '*';
        } else if (event < 12) {
                resp = '#';
        } else if (event < 16) {
                resp = 'A' + (event - 12);
        } else if (event < 17) {
                resp = 'X';
        }
        if ((!rtp->resp && power) || (rtp->resp && (rtp->resp != resp))) {
                rtp->resp = resp;
                /* Why we should care on DTMF compensation at reception? */
                if (!ast_test_flag(rtp, FLAG_DTMF_COMPENSATE)) {
                        f = send_dtmf(rtp, AST_FRAME_DTMF_BEGIN);
                        rtp->dtmfsamples = 0;
                }
        } else if ((rtp->resp == resp) && !power) {
                f = send_dtmf(rtp, AST_FRAME_DTMF_END);
                f->samples = rtp->dtmfsamples * 8;
                rtp->resp = 0;
        } else if (rtp->resp == resp)
                rtp->dtmfsamples += 20 * 8;
        rtp->dtmfcount = dtmftimeout;
        return f;
}

/*! 
 * \brief Process RTP DTMF and events according to RFC 2833.
 * 
 * RFC 2833 is "RTP Payload for DTMF Digits, Telephony Tones and Telephony Signals".
 * 
 * \param rtp
 * \param data
 * \param len
 * \param seqno
 * \param timestamp
 * \returns
 */
static struct ast_frame *process_rfc2833(struct ast_rtp *rtp, unsigned char *data, int len, unsigned int seqno, unsigned int timestamp)
{
        unsigned int event;
        unsigned int event_end;
        unsigned int samples;
        char resp = 0;
        struct ast_frame *f = NULL;

        /* Figure out event, event end, and samples */
        event = ntohl(*((unsigned int *)(data)));
        event >>= 24;
        event_end = ntohl(*((unsigned int *)(data)));
        event_end <<= 8;
        event_end >>= 24;
        samples = ntohl(*((unsigned int *)(data)));
        samples &= 0xFFFF;

        /* Print out debug if turned on */
        if (rtpdebug || option_debug > 2)
                ast_debug(0, "- RTP 2833 Event: %08x (len = %d)\n", event, len);

        /* Figure out what digit was pressed */
        if (event < 10) {
                resp = '0' + event;
        } else if (event < 11) {
                resp = '*';
        } else if (event < 12) {
                resp = '#';
        } else if (event < 16) {
                resp = 'A' + (event - 12);
        } else if (event < 17) {        /* Event 16: Hook flash */
                resp = 'X';     
        } else {
                /* Not a supported event */
                ast_log(LOG_DEBUG, "Ignoring RTP 2833 Event: %08x. Not a DTMF Digit.\n", event);
                return &ast_null_frame;
        }
        
        if (ast_test_flag(rtp, FLAG_DTMF_COMPENSATE)) {
                if ((rtp->lastevent != timestamp) || (rtp->resp && rtp->resp != resp)) {
                        rtp->resp = resp;
                        f = send_dtmf(rtp, AST_FRAME_DTMF_END);
                        f->len = 0;
                        rtp->lastevent = timestamp;
                }
        } else {
                if ((!(rtp->resp) && (!(event_end & 0x80))) || (rtp->resp && rtp->resp != resp)) {
                        rtp->resp = resp;
                        f = send_dtmf(rtp, AST_FRAME_DTMF_BEGIN);
                } else if ((event_end & 0x80) && (rtp->lastevent != seqno) && rtp->resp) {
                        f = send_dtmf(rtp, AST_FRAME_DTMF_END);
                        f->len = ast_tvdiff_ms(ast_samp2tv(samples, 8000), ast_tv(0, 0)); /* XXX hard coded 8kHz */
                        rtp->resp = 0;
                        rtp->lastevent = seqno;
                }
        }

        rtp->dtmfcount = dtmftimeout;
        rtp->dtmfsamples = samples;

        return f;
}

/*!
 * \brief Process Comfort Noise RTP.
 * 
 * This is incomplete at the moment.
 * 
*/
static struct ast_frame *process_rfc3389(struct ast_rtp *rtp, unsigned char *data, int len)
{
        struct ast_frame *f = NULL;
        /* Convert comfort noise into audio with various codecs.  Unfortunately this doesn't
           totally help us out becuase we don't have an engine to keep it going and we are not
           guaranteed to have it every 20ms or anything */
        if (rtpdebug)
                ast_debug(0, "- RTP 3389 Comfort noise event: Level %d (len = %d)\n", rtp->lastrxformat, len);

        if (!(ast_test_flag(rtp, FLAG_3389_WARNING))) {
                ast_log(LOG_NOTICE, "Comfort noise support incomplete in Asterisk (RFC 3389). Please turn off on client if possible. Client IP: %s\n",
                        ast_inet_ntoa(rtp->them.sin_addr));
                ast_set_flag(rtp, FLAG_3389_WARNING);
        }
        
        /* Must have at least one byte */
        if (!len)
                return NULL;
        if (len < 24) {
                rtp->f.data = rtp->rawdata + AST_FRIENDLY_OFFSET;
                rtp->f.datalen = len - 1;
                rtp->f.offset = AST_FRIENDLY_OFFSET;
                memcpy(rtp->f.data, data + 1, len - 1);
        } else {
                rtp->f.data = NULL;
                rtp->f.offset = 0;
                rtp->f.datalen = 0;
        }
        rtp->f.frametype = AST_FRAME_CNG;
        rtp->f.subclass = data[0] & 0x7f;
        rtp->f.datalen = len - 1;
        rtp->f.samples = 0;
        rtp->f.delivery.tv_usec = rtp->f.delivery.tv_sec = 0;
        f = &rtp->f;
        return f;
}

static int rtpread(int *id, int fd, short events, void *cbdata)
{
        struct ast_rtp *rtp = cbdata;
        struct ast_frame *f;
        f = ast_rtp_read(rtp);
        if (f) {
                if (rtp->callback)
                        rtp->callback(rtp, f, rtp->data);
        }
        return 1;
}

struct ast_frame *ast_rtcp_read(struct ast_rtp *rtp)
{
        socklen_t len;
        int position, i, packetwords;
        int res;
        struct sockaddr_in sin;
        unsigned int rtcpdata[8192 + AST_FRIENDLY_OFFSET];
        unsigned int *rtcpheader;
        int pt;
        struct timeval now;
        unsigned int length;
        int rc;
        double rttsec;
        uint64_t rtt = 0;
        unsigned int dlsr;
        unsigned int lsr;
        unsigned int msw;
        unsigned int lsw;
        unsigned int comp;
        struct ast_frame *f = &ast_null_frame;
        
        if (!rtp || !rtp->rtcp)
                return &ast_null_frame;

        len = sizeof(sin);
        
        res = recvfrom(rtp->rtcp->s, rtcpdata + AST_FRIENDLY_OFFSET, sizeof(rtcpdata) - sizeof(unsigned int) * AST_FRIENDLY_OFFSET,
                                        0, (struct sockaddr *)&sin, &len);
        rtcpheader = (unsigned int *)(rtcpdata + AST_FRIENDLY_OFFSET);
        
        if (res < 0) {
                if (errno == EBADF)
                        CRASH;
                if (errno != EAGAIN) {
                        ast_log(LOG_WARNING, "RTCP Read error: %s.  Hanging up.\n", strerror(errno));
                        return NULL;
                }
                return &ast_null_frame;
        }

        packetwords = res / 4;
        
        if (rtp->nat) {
                /* Send to whoever sent to us */
                if ((rtp->rtcp->them.sin_addr.s_addr != sin.sin_addr.s_addr) ||
                    (rtp->rtcp->them.sin_port != sin.sin_port)) {
                        memcpy(&rtp->rtcp->them, &sin, sizeof(rtp->rtcp->them));
                        if (option_debug || rtpdebug)
                                ast_debug(0, "RTCP NAT: Got RTCP from other end. Now sending to address %s:%d\n", ast_inet_ntoa(rtp->rtcp->them.sin_addr), ntohs(rtp->rtcp->them.sin_port));
                }
        }

        ast_debug(1, "Got RTCP report of %d bytes\n", res);

        /* Process a compound packet */
        position = 0;
        while (position < packetwords) {
                i = position;
                length = ntohl(rtcpheader[i]);
                pt = (length & 0xff0000) >> 16;
                rc = (length & 0x1f000000) >> 24;
                length &= 0xffff;
    
                if ((i + length) > packetwords) {
                        ast_log(LOG_WARNING, "RTCP Read too short\n");
                        return &ast_null_frame;
                }
                
                if (rtcp_debug_test_addr(&sin)) {
                        ast_verbose("\n\nGot RTCP from %s:%d\n", ast_inet_ntoa(sin.sin_addr), ntohs(sin.sin_port));
                        ast_verbose("PT: %d(%s)\n", pt, (pt == 200) ? "Sender Report" : (pt == 201) ? "Receiver Report" : (pt == 192) ? "H.261 FUR" : "Unknown");
                        ast_verbose("Reception reports: %d\n", rc);
                        ast_verbose("SSRC of sender: %u\n", rtcpheader[i + 1]);
                }
    
                i += 2; /* Advance past header and ssrc */
                
                switch (pt) {
                case RTCP_PT_SR:
                        gettimeofday(&rtp->rtcp->rxlsr,NULL); /* To be able to populate the dlsr */
                        rtp->rtcp->spc = ntohl(rtcpheader[i+3]);
                        rtp->rtcp->soc = ntohl(rtcpheader[i + 4]);
                        rtp->rtcp->themrxlsr = ((ntohl(rtcpheader[i]) & 0x0000ffff) << 16) | ((ntohl(rtcpheader[i + 1]) & 0xffff0000) >> 16); /* Going to LSR in RR*/
    
                        if (rtcp_debug_test_addr(&sin)) {
                                ast_verbose("NTP timestamp: %lu.%010lu\n", (unsigned long) ntohl(rtcpheader[i]), (unsigned long) ntohl(rtcpheader[i + 1]) * 4096);
                                ast_verbose("RTP timestamp: %lu\n", (unsigned long) ntohl(rtcpheader[i + 2]));
                                ast_verbose("SPC: %lu\tSOC: %lu\n", (unsigned long) ntohl(rtcpheader[i + 3]), (unsigned long) ntohl(rtcpheader[i + 4]));
                        }
                        i += 5;
                        if (rc < 1)
                                break;
                        /* Intentional fall through */
                case RTCP_PT_RR:
                        /* Don't handle multiple reception reports (rc > 1) yet */
                        /* Calculate RTT per RFC */
                        gettimeofday(&now, NULL);
                        timeval2ntp(now, &msw, &lsw);
                        if (ntohl(rtcpheader[i + 4]) && ntohl(rtcpheader[i + 5])) { /* We must have the LSR && DLSR */
                                comp = ((msw & 0xffff) << 16) | ((lsw & 0xffff0000) >> 16);
                                lsr = ntohl(rtcpheader[i + 4]);
                                dlsr = ntohl(rtcpheader[i + 5]);
                                rtt = comp - lsr - dlsr;

                                /* Convert end to end delay to usec (keeping the calculation in 64bit space)
                                   sess->ee_delay = (eedelay * 1000) / 65536; */
                                if (rtt < 4294) {
                                    rtt = (rtt * 1000000) >> 16;
                                } else {
                                    rtt = (rtt * 1000) >> 16;
                                    rtt *= 1000;
                                }
                                rtt = rtt / 1000.;
                                rttsec = rtt / 1000.;

                                if (comp - dlsr >= lsr) {
                                        rtp->rtcp->accumulated_transit += rttsec;
                                        rtp->rtcp->rtt = rttsec;
                                        if (rtp->rtcp->maxrtt<rttsec)
                                                rtp->rtcp->maxrtt = rttsec;
                                        if (rtp->rtcp->minrtt>rttsec)
                                                rtp->rtcp->minrtt = rttsec;
                                } else if (rtcp_debug_test_addr(&sin)) {
                                        ast_verbose("Internal RTCP NTP clock skew detected: "
                                                           "lsr=%u, now=%u, dlsr=%u (%d:%03dms), "
                                                           "diff=%d\n",
                                                           lsr, comp, dlsr, dlsr / 65536,
                                                           (dlsr % 65536) * 1000 / 65536,
                                                           dlsr - (comp - lsr));
                                }
                        }

                        rtp->rtcp->reported_jitter = ntohl(rtcpheader[i + 3]);
                        rtp->rtcp->reported_lost = ntohl(rtcpheader[i + 1]) & 0xffffff;
                        if (rtcp_debug_test_addr(&sin)) {
                                ast_verbose("  Fraction lost: %ld\n", (((long) ntohl(rtcpheader[i + 1]) & 0xff000000) >> 24));
                                ast_verbose("  Packets lost so far: %d\n", rtp->rtcp->reported_lost);
                                ast_verbose("  Highest sequence number: %ld\n", (long) (ntohl(rtcpheader[i + 2]) & 0xffff));
                                ast_verbose("  Sequence number cycles: %ld\n", (long) (ntohl(rtcpheader[i + 2]) & 0xffff) >> 16);
                                ast_verbose("  Interarrival jitter: %u\n", rtp->rtcp->reported_jitter);
                                ast_verbose("  Last SR(our NTP): %lu.%010lu\n",(unsigned long) ntohl(rtcpheader[i + 4]) >> 16,((unsigned long) ntohl(rtcpheader[i + 4]) << 16) * 4096);
                                ast_verbose("  DLSR: %4.4f (sec)\n",ntohl(rtcpheader[i + 5])/65536.0);
                                if (rtt)
                                        ast_verbose("  RTT: %lu(sec)\n", (unsigned long) rtt);
                        }
                        if (rtt) {
                                manager_event(EVENT_FLAG_REPORTING, "RTCPReceived", "From %s:%d\r\n"
                                                                    "PT: %d(%s)\r\n"
                                                                    "ReceptionReports: %d\r\n"
                                                                    "SenderSSRC: %u\r\n"
                                                                    "FractionLost: %ld\r\n"
                                                                    "PacketsLost: %d\r\n"
                                                                    "HighestSequence: %ld\r\n"
                                                                    "SequenceNumberCycles: %ld\r\n"
                                                                    "IAJitter: %u\r\n"
                                                                    "LastSR: %lu.%010lu\r\n"
                                                                    "DLSR: %4.4f(sec)\r\n"
                                                                    "RTT: %llu(sec)\r\n",
                                                                    ast_inet_ntoa(sin.sin_addr), ntohs(sin.sin_port),
                                                                    pt, (pt == 200) ? "Sender Report" : (pt == 201) ? "Receiver Report" : (pt == 192) ? "H.261 FUR" : "Unknown",
                                                                    rc,
                                                                    rtcpheader[i + 1],
                                                                    (((long) ntohl(rtcpheader[i + 1]) & 0xff000000) >> 24),
                                                                    rtp->rtcp->reported_lost,
                                                                    (long) (ntohl(rtcpheader[i + 2]) & 0xffff),
                                                                    (long) (ntohl(rtcpheader[i + 2]) & 0xffff) >> 16,
                                                                    rtp->rtcp->reported_jitter,
                                                                    (unsigned long) ntohl(rtcpheader[i + 4]) >> 16, ((unsigned long) ntohl(rtcpheader[i + 4]) << 16) * 4096,
                                                                    ntohl(rtcpheader[i + 5])/65536.0,
                                                                    (unsigned long long)rtt);
                        } else {
                                manager_event(EVENT_FLAG_REPORTING, "RTCPReceived", "From %s:%d\r\n"
                                                                    "PT: %d(%s)\r\n"
                                                                    "ReceptionReports: %d\r\n"
                                                                    "SenderSSRC: %u\r\n"
                                                                    "FractionLost: %ld\r\n"
                                                                    "PacketsLost: %d\r\n"
                                                                    "HighestSequence: %ld\r\n"
                                                                    "SequenceNumberCycles: %ld\r\n"
                                                                    "IAJitter: %u\r\n"
                                                                    "LastSR: %lu.%010lu\r\n"
                                                                    "DLSR: %4.4f(sec)\r\n",
                                                                    ast_inet_ntoa(sin.sin_addr), ntohs(sin.sin_port),
                                                                    pt, (pt == 200) ? "Sender Report" : (pt == 201) ? "Receiver Report" : (pt == 192) ? "H.261 FUR" : "Unknown",
                                                                    rc,
                                                                    rtcpheader[i + 1],
                                                                    (((long) ntohl(rtcpheader[i + 1]) & 0xff000000) >> 24),
                                                                    rtp->rtcp->reported_lost,
                                                                    (long) (ntohl(rtcpheader[i + 2]) & 0xffff),
                                                                    (long) (ntohl(rtcpheader[i + 2]) & 0xffff) >> 16,
                                                                    rtp->rtcp->reported_jitter,
                                                                    (unsigned long) ntohl(rtcpheader[i + 4]) >> 16,
                                                                    ((unsigned long) ntohl(rtcpheader[i + 4]) << 16) * 4096,
                                                                    ntohl(rtcpheader[i + 5])/65536.0);
                        }
                        break;
                case RTCP_PT_FUR:
                        if (rtcp_debug_test_addr(&sin))
                                ast_verbose("Received an RTCP Fast Update Request\n");
                        rtp->f.frametype = AST_FRAME_CONTROL;
                        rtp->f.subclass = AST_CONTROL_VIDUPDATE;
                        rtp->f.datalen = 0;
                        rtp->f.samples = 0;
                        rtp->f.mallocd = 0;
                        rtp->f.src = "RTP";
                        f = &rtp->f;
                        break;
                case RTCP_PT_SDES:
                        if (rtcp_debug_test_addr(&sin))
                                ast_verbose("Received an SDES from %s:%d\n", ast_inet_ntoa(rtp->rtcp->them.sin_addr), ntohs(rtp->rtcp->them.sin_port));
                        break;
                case RTCP_PT_BYE:
                        if (rtcp_debug_test_addr(&sin))
                                ast_verbose("Received a BYE from %s:%d\n", ast_inet_ntoa(rtp->rtcp->them.sin_addr), ntohs(rtp->rtcp->them.sin_port));
                        break;
                default:
                        ast_debug(1, "Unknown RTCP packet (pt=%d) received from %s:%d\n", pt, ast_inet_ntoa(rtp->rtcp->them.sin_addr), ntohs(rtp->rtcp->them.sin_port));
                        break;
                }
                position += (length + 1);
        }
                        
        return f;
}

static void calc_rxstamp(struct timeval *tv, struct ast_rtp *rtp, unsigned int timestamp, int mark)
{
        struct timeval now;
        double transit;
        double current_time;
        double d;
        double dtv;
        double prog;
        
        if ((!rtp->rxcore.tv_sec && !rtp->rxcore.tv_usec) || mark) {
                gettimeofday(&rtp->rxcore, NULL);
                rtp->drxcore = (double) rtp->rxcore.tv_sec + (double) rtp->rxcore.tv_usec / 1000000;
                /* map timestamp to a real time */
                rtp->seedrxts = timestamp; /* Their RTP timestamp started with this */
                rtp->rxcore.tv_sec -= timestamp / 8000;
                rtp->rxcore.tv_usec -= (timestamp % 8000) * 125;
                /* Round to 0.1ms for nice, pretty timestamps */
                rtp->rxcore.tv_usec -= rtp->rxcore.tv_usec % 100;
                if (rtp->rxcore.tv_usec < 0) {
                        /* Adjust appropriately if necessary */
                        rtp->rxcore.tv_usec += 1000000;
                        rtp->rxcore.tv_sec -= 1;
                }
        }

        gettimeofday(&now,NULL);
        /* rxcore is the mapping between the RTP timestamp and _our_ real time from gettimeofday() */
        tv->tv_sec = rtp->rxcore.tv_sec + timestamp / 8000;
        tv->tv_usec = rtp->rxcore.tv_usec + (timestamp % 8000) * 125;
        if (tv->tv_usec >= 1000000) {
                tv->tv_usec -= 1000000;
                tv->tv_sec += 1;
        }
        prog = (double)((timestamp-rtp->seedrxts)/8000.);
        dtv = (double)rtp->drxcore + (double)(prog);
        current_time = (double)now.tv_sec + (double)now.tv_usec/1000000;
        transit = current_time - dtv;
        d = transit - rtp->rxtransit;
        rtp->rxtransit = transit;
        if (d<0)
                d=-d;
        rtp->rxjitter += (1./16.) * (d - rtp->rxjitter);
        if (rtp->rtcp && rtp->rxjitter > rtp->rtcp->maxrxjitter)
                rtp->rtcp->maxrxjitter = rtp->rxjitter;
        if (rtp->rtcp && rtp->rxjitter < rtp->rtcp->minrxjitter)
                rtp->rtcp->minrxjitter = rtp->rxjitter;
}

/*! \brief Perform a Packet2Packet RTP write */
static int bridge_p2p_rtp_write(struct ast_rtp *rtp, struct ast_rtp *bridged, unsigned int *rtpheader, int len, int hdrlen)
{
        int res = 0, payload = 0, bridged_payload = 0, mark;
        struct rtpPayloadType rtpPT;
        int reconstruct = ntohl(rtpheader[0]);

        /* Get fields from packet */
        payload = (reconstruct & 0x7f0000) >> 16;
        mark = (((reconstruct & 0x800000) >> 23) != 0);

        /* Check what the payload value should be */
        rtpPT = ast_rtp_lookup_pt(rtp, payload);

        /* If the payload is DTMF, and we are listening for DTMF - then feed it into the core */
        if (ast_test_flag(rtp, FLAG_P2P_NEED_DTMF) && !rtpPT.isAstFormat && rtpPT.code == AST_RTP_DTMF)
                return -1;

        /* Otherwise adjust bridged payload to match */
        bridged_payload = ast_rtp_lookup_code(bridged, rtpPT.isAstFormat, rtpPT.code);

        /* If the mark bit has not been sent yet... do it now */
        if (!ast_test_flag(rtp, FLAG_P2P_SENT_MARK)) {
                mark = 1;
                ast_set_flag(rtp, FLAG_P2P_SENT_MARK);
        }

        /* Reconstruct part of the packet */
        reconstruct &= 0xFF80FFFF;
        reconstruct |= (bridged_payload << 16);
        reconstruct |= (mark << 23);
        rtpheader[0] = htonl(reconstruct);

        /* Send the packet back out */
        res = sendto(bridged->s, (void *)rtpheader, len, 0, (struct sockaddr *)&bridged->them, sizeof(bridged->them));
        if (res < 0) {
                if (!bridged->nat || (bridged->nat && (ast_test_flag(bridged, FLAG_NAT_ACTIVE) == FLAG_NAT_ACTIVE))) {
                        ast_debug(1, "RTP Transmission error of packet to %s:%d: %s\n", ast_inet_ntoa(bridged->them.sin_addr), ntohs(bridged->them.sin_port), strerror(errno));
                } else if (((ast_test_flag(bridged, FLAG_NAT_ACTIVE) == FLAG_NAT_INACTIVE) || rtpdebug) && !ast_test_flag(bridged, FLAG_NAT_INACTIVE_NOWARN)) {
                        if (option_debug || rtpdebug)
                                ast_debug(0, "RTP NAT: Can't write RTP to private address %s:%d, waiting for other end to send audio...\n", ast_inet_ntoa(bridged->them.sin_addr), ntohs(bridged->them.sin_port));
                        ast_set_flag(bridged, FLAG_NAT_INACTIVE_NOWARN);
                }
                return 0;
        } else if (rtp_debug_test_addr(&bridged->them))
                        ast_verbose("Sent RTP P2P packet to %s:%u (type %-2.2d, len %-6.6u)\n", ast_inet_ntoa(bridged->them.sin_addr), ntohs(bridged->them.sin_port), bridged_payload, len - hdrlen);

        return 0;
}

struct ast_frame *ast_rtp_read(struct ast_rtp *rtp)
{
        int res;
        struct sockaddr_in sin;
        socklen_t len;
        unsigned int seqno;
        int version;
        int payloadtype;
        int hdrlen = 12;
        int padding;
        int mark;
        int ext;
        int cc;
        unsigned int ssrc;
        unsigned int timestamp;
        unsigned int *rtpheader;
        struct rtpPayloadType rtpPT;
        struct ast_rtp *bridged = NULL;
        
        /* If time is up, kill it */
        if (rtp->sending_digit)
                ast_rtp_senddigit_continuation(rtp);

        len = sizeof(sin);
        
        /* Cache where the header will go */
        res = recvfrom(rtp->s, rtp->rawdata + AST_FRIENDLY_OFFSET, sizeof(rtp->rawdata) - AST_FRIENDLY_OFFSET,
                                        0, (struct sockaddr *)&sin, &len);

        rtpheader = (unsigned int *)(rtp->rawdata + AST_FRIENDLY_OFFSET);
        if (res < 0) {
                if (errno == EBADF)
                        CRASH;
                if (errno != EAGAIN) {
                        ast_log(LOG_WARNING, "RTP Read error: %s.  Hanging up.\n", strerror(errno));
                        return NULL;
                }
                return &ast_null_frame;
        }
        
        if (res < hdrlen) {
                ast_log(LOG_WARNING, "RTP Read too short\n");
                return &ast_null_frame;
        }

        /* Get fields */
        seqno = ntohl(rtpheader[0]);

        /* Check RTP version */
        version = (seqno & 0xC0000000) >> 30;
        if (!version) {
                /* If the two high bits are 0, this might be a
                 * STUN message, so process it. stun_handle_packet()
                 * answers to requests, and it returns STUN_ACCEPT
                 * if the request is valid.
                 */
                if ((stun_handle_packet(rtp->s, &sin, rtp->rawdata + AST_FRIENDLY_OFFSET, res, NULL, NULL) == STUN_ACCEPT) &&
                        (!rtp->them.sin_port && !rtp->them.sin_addr.s_addr)) {
                        memcpy(&rtp->them, &sin, sizeof(rtp->them));
                }
                return &ast_null_frame;
        }

#if 0   /* Allow to receive RTP stream with closed transmission path */
        /* If we don't have the other side's address, then ignore this */
        if (!rtp->them.sin_addr.s_addr || !rtp->them.sin_port)
                return &ast_null_frame;
#endif

        /* Send to whoever send to us if NAT is turned on */
        if (rtp->nat) {
                if ((rtp->them.sin_addr.s_addr != sin.sin_addr.s_addr) ||
                    (rtp->them.sin_port != sin.sin_port)) {
                        rtp->them = sin;
                        if (rtp->rtcp) {
                                memcpy(&rtp->rtcp->them, &sin, sizeof(rtp->rtcp->them));
                                rtp->rtcp->them.sin_port = htons(ntohs(rtp->them.sin_port)+1);
                        }
                        rtp->rxseqno = 0;
                        ast_set_flag(rtp, FLAG_NAT_ACTIVE);
                        if (option_debug || rtpdebug)
                                ast_debug(0, "RTP NAT: Got audio from other end. Now sending to address %s:%d\n", ast_inet_ntoa(rtp->them.sin_addr), ntohs(rtp->them.sin_port));
                }
        }

        /* If we are bridged to another RTP stream, send direct */
        if ((bridged = ast_rtp_get_bridged(rtp)) && !bridge_p2p_rtp_write(rtp, bridged, rtpheader, res, hdrlen))
                return &ast_null_frame;

        if (version != 2)
                return &ast_null_frame;

        payloadtype = (seqno & 0x7f0000) >> 16;
        padding = seqno & (1 << 29);
        mark = seqno & (1 << 23);
        ext = seqno & (1 << 28);
        cc = (seqno & 0xF000000) >> 24;
        seqno &= 0xffff;
        timestamp = ntohl(rtpheader[1]);
        ssrc = ntohl(rtpheader[2]);
        
        if (!mark && rtp->rxssrc && rtp->rxssrc != ssrc) {
                if (option_debug || rtpdebug)
                        ast_debug(0, "Forcing Marker bit, because SSRC has changed\n");
                mark = 1;
        }

        rtp->rxssrc = ssrc;
        
        if (padding) {
                /* Remove padding bytes */
                res -= rtp->rawdata[AST_FRIENDLY_OFFSET + res - 1];
        }
        
        if (cc) {
                /* CSRC fields present */
                hdrlen += cc*4;
        }

        if (ext) {
                /* RTP Extension present */
                hdrlen += (ntohl(rtpheader[hdrlen/4]) & 0xffff) << 2;
                hdrlen += 4;
                if (option_debug) {
                        int profile;
                        profile = (ntohl(rtpheader[3]) & 0xffff0000) >> 16;
                        if (profile == 0x505a)
                                ast_debug(1, "Found Zfone extension in RTP stream - zrtp - not supported.\n");
                        else
                                ast_debug(1, "Found unknown RTP Extensions %x\n", profile);
                }
        }

        if (res < hdrlen) {
                ast_log(LOG_WARNING, "RTP Read too short (%d, expecting %d)\n", res, hdrlen);
                return &ast_null_frame;
        }

        rtp->rxcount++; /* Only count reasonably valid packets, this'll make the rtcp stats more accurate */

        if (rtp->rxcount==1) {
                /* This is the first RTP packet successfully received from source */
                rtp->seedrxseqno = seqno;
        }

        /* Do not schedule RR if RTCP isn't run */
        if (rtp->rtcp && rtp->rtcp->them.sin_addr.s_addr && rtp->rtcp->schedid < 1) {
                /* Schedule transmission of Receiver Report */
                rtp->rtcp->schedid = ast_sched_add(rtp->sched, ast_rtcp_calc_interval(rtp), ast_rtcp_write, rtp);
        }
        if ( (int)rtp->lastrxseqno - (int)seqno  > 100) /* if so it would indicate that the sender cycled; allow for misordering */
                rtp->cycles += RTP_SEQ_MOD;

        rtp->lastrxseqno = seqno;
        
        if (rtp->themssrc==0)
                rtp->themssrc = ntohl(rtpheader[2]); /* Record their SSRC to put in future RR */
        
        if (rtp_debug_test_addr(&sin))
                ast_verbose("Got  RTP packet from    %s:%u (type %-2.2d, seq %-6.6u, ts %-6.6u, len %-6.6u)\n",
                        ast_inet_ntoa(sin.sin_addr), ntohs(sin.sin_port), payloadtype, seqno, timestamp,res - hdrlen);

        rtpPT = ast_rtp_lookup_pt(rtp, payloadtype);
        if (!rtpPT.isAstFormat) {
                struct ast_frame *f = NULL;

                /* This is special in-band data that's not one of our codecs */
                if (rtpPT.code == AST_RTP_DTMF) {
                        /* It's special -- rfc2833 process it */
                        if (rtp_debug_test_addr(&sin)) {
                                unsigned char *data;
                                unsigned int event;
                                unsigned int event_end;
                                unsigned int duration;
                                data = rtp->rawdata + AST_FRIENDLY_OFFSET + hdrlen;
                                event = ntohl(*((unsigned int *)(data)));
                                event >>= 24;
                                event_end = ntohl(*((unsigned int *)(data)));
                                event_end <<= 8;
                                event_end >>= 24;
                                duration = ntohl(*((unsigned int *)(data)));
                                duration &= 0xFFFF;
                                ast_verbose("Got  RTP RFC2833 from   %s:%u (type %-2.2d, seq %-6.6u, ts %-6.6u, len %-6.6u, mark %d, event %08x, end %d, duration %-5.5d) \n", ast_inet_ntoa(sin.sin_addr), ntohs(sin.sin_port), payloadtype, seqno, timestamp, res - hdrlen, (mark?1:0), event, ((event_end & 0x80)?1:0), duration);
                        }
                        f = process_rfc2833(rtp, rtp->rawdata + AST_FRIENDLY_OFFSET + hdrlen, res - hdrlen, seqno, timestamp);
                } else if (rtpPT.code == AST_RTP_CISCO_DTMF) {
                        /* It's really special -- process it the Cisco way */
                        if (rtp->lastevent <= seqno || (rtp->lastevent >= 65530 && seqno <= 6)) {
                                f = process_cisco_dtmf(rtp, rtp->rawdata + AST_FRIENDLY_OFFSET + hdrlen, res - hdrlen);
                                rtp->lastevent = seqno;
                        }
                } else if (rtpPT.code == AST_RTP_CN) {
                        /* Comfort Noise */
                        f = process_rfc3389(rtp, rtp->rawdata + AST_FRIENDLY_OFFSET + hdrlen, res - hdrlen);
                } else {
                        ast_log(LOG_NOTICE, "Unknown RTP codec %d received from '%s'\n", payloadtype, ast_inet_ntoa(rtp->them.sin_addr));
                }
                return f ? f : &ast_null_frame;
        }
        rtp->lastrxformat = rtp->f.subclass = rtpPT.code;
        rtp->f.frametype = (rtp->f.subclass < AST_FORMAT_MAX_AUDIO) ? AST_FRAME_VOICE : (rtp->f.subclass < AST_FORMAT_MAX_VIDEO) ? AST_FRAME_VIDEO : AST_FRAME_TEXT;

        if (!rtp->lastrxts)
                rtp->lastrxts = timestamp;

        rtp->rxseqno = seqno;

        /* Record received timestamp as last received now */
        rtp->lastrxts = timestamp;

        rtp->f.mallocd = 0;
        rtp->f.datalen = res - hdrlen;
        rtp->f.data = rtp->rawdata + hdrlen + AST_FRIENDLY_OFFSET;
        rtp->f.offset = hdrlen + AST_FRIENDLY_OFFSET;
        rtp->f.seqno = seqno;
        if (rtp->f.subclass < AST_FORMAT_MAX_AUDIO) {
                rtp->f.samples = ast_codec_get_samples(&rtp->f);
                if (rtp->f.subclass == AST_FORMAT_SLINEAR) 
                        ast_frame_byteswap_be(&rtp->f);
                calc_rxstamp(&rtp->f.delivery, rtp, timestamp, mark);
                /* Add timing data to let ast_generic_bridge() put the frame into a jitterbuf */
                rtp->f.has_timing_info = 1;
                rtp->f.ts = timestamp / 8;
                rtp->f.len = rtp->f.samples / 8;
        } else if(rtp->f.subclass < AST_FORMAT_MAX_VIDEO) {
                /* Video -- samples is # of samples vs. 90000 */
                if (!rtp->lastividtimestamp)
                        rtp->lastividtimestamp = timestamp;
                rtp->f.samples = timestamp - rtp->lastividtimestamp;
                rtp->lastividtimestamp = timestamp;
                rtp->f.delivery.tv_sec = 0;
                rtp->f.delivery.tv_usec = 0;
                /* Pass the RTP marker bit as bit 0 in the subclass field.
                 * This is ok because subclass is actually a bitmask, and
                 * the low bits represent audio formats, that are not
                 * involved here since we deal with video.
                 */
                if (mark)
                        rtp->f.subclass |= 0x1;
        } else {
                /* TEXT -- samples is # of samples vs. 1000 */
                if (!rtp->lastitexttimestamp)
                        rtp->lastitexttimestamp = timestamp;
                rtp->f.samples = timestamp - rtp->lastitexttimestamp;
                rtp->lastitexttimestamp = timestamp;
                rtp->f.delivery.tv_sec = 0;
                rtp->f.delivery.tv_usec = 0;
        }
        rtp->f.src = "RTP";
        return &rtp->f;
}

/* The following array defines the MIME Media type (and subtype) for each
   of our codecs, or RTP-specific data type. */
static struct {
        struct rtpPayloadType payloadType;
        char* type;
        char* subtype;
} mimeTypes[] = {
        {{1, AST_FORMAT_G723_1}, "audio", "G723"},
        {{1, AST_FORMAT_GSM}, "audio", "GSM"},
        {{1, AST_FORMAT_ULAW}, "audio", "PCMU"},
        {{1, AST_FORMAT_ALAW}, "audio", "PCMA"},
        {{1, AST_FORMAT_G726}, "audio", "G726-32"},
        {{1, AST_FORMAT_ADPCM}, "audio", "DVI4"},
        {{1, AST_FORMAT_SLINEAR}, "audio", "L16"},
        {{1, AST_FORMAT_LPC10}, "audio", "LPC"},
        {{1, AST_FORMAT_G729A}, "audio", "G729"},
        {{1, AST_FORMAT_SPEEX}, "audio", "speex"},
        {{1, AST_FORMAT_ILBC}, "audio", "iLBC"},
        {{1, AST_FORMAT_G722}, "audio", "G722"},
        {{1, AST_FORMAT_G726_AAL2}, "audio", "AAL2-G726-32"},
        {{0, AST_RTP_DTMF}, "audio", "telephone-event"},
        {{0, AST_RTP_CISCO_DTMF}, "audio", "cisco-telephone-event"},
        {{0, AST_RTP_CN}, "audio", "CN"},
        {{1, AST_FORMAT_JPEG}, "video", "JPEG"},
        {{1, AST_FORMAT_PNG}, "video", "PNG"},
        {{1, AST_FORMAT_H261}, "video", "H261"},
        {{1, AST_FORMAT_H263}, "video", "H263"},
        {{1, AST_FORMAT_H263_PLUS}, "video", "h263-1998"},
        {{1, AST_FORMAT_H264}, "video", "H264"},
        {{1, AST_FORMAT_MP4_VIDEO}, "video", "MP4V-ES"},
        {{1, AST_FORMAT_T140}, "text", "T140"},
};

/*! 
 * \brief Mapping between Asterisk codecs and rtp payload types
 *
 * Static (i.e., well-known) RTP payload types for our "AST_FORMAT..."s:
 * also, our own choices for dynamic payload types.  This is our master
 * table for transmission 
 * 
 * See http://www.iana.org/assignments/rtp-parameters for a list of
 * assigned values
 */
static struct rtpPayloadType static_RTP_PT[MAX_RTP_PT] = {
        [0] = {1, AST_FORMAT_ULAW},
#ifdef USE_DEPRECATED_G726
        [2] = {1, AST_FORMAT_G726}, /* Technically this is G.721, but if Cisco can do it, so can we... */
#endif
        [3] = {1, AST_FORMAT_GSM},
        [4] = {1, AST_FORMAT_G723_1},
        [5] = {1, AST_FORMAT_ADPCM}, /* 8 kHz */
        [6] = {1, AST_FORMAT_ADPCM}, /* 16 kHz */
        [7] = {1, AST_FORMAT_LPC10},
        [8] = {1, AST_FORMAT_ALAW},
        [9] = {1, AST_FORMAT_G722},
        [10] = {1, AST_FORMAT_SLINEAR}, /* 2 channels */
        [11] = {1, AST_FORMAT_SLINEAR}, /* 1 channel */
        [13] = {0, AST_RTP_CN},
        [16] = {1, AST_FORMAT_ADPCM}, /* 11.025 kHz */
        [17] = {1, AST_FORMAT_ADPCM}, /* 22.050 kHz */
        [18] = {1, AST_FORMAT_G729A},
        [19] = {0, AST_RTP_CN},         /* Also used for CN */
        [26] = {1, AST_FORMAT_JPEG},
        [31] = {1, AST_FORMAT_H261},
        [34] = {1, AST_FORMAT_H263},
        [97] = {1, AST_FORMAT_ILBC},
        [98] = {1, AST_FORMAT_H263_PLUS},
        [99] = {1, AST_FORMAT_H264},
        [101] = {0, AST_RTP_DTMF},
        [102] = {1, AST_FORMAT_T140},   /* Real time text chat */
        [103] = {1, AST_FORMAT_H263_PLUS},
        [104] = {1, AST_FORMAT_MP4_VIDEO},
        [110] = {1, AST_FORMAT_SPEEX},
        [111] = {1, AST_FORMAT_G726},
        [112] = {1, AST_FORMAT_G726_AAL2},
        [121] = {0, AST_RTP_CISCO_DTMF}, /* Must be type 121 */
};

void ast_rtp_pt_clear(struct ast_rtp* rtp) 
{
        int i;

        if (!rtp)
                return;

        rtp_bridge_lock(rtp);

        for (i = 0; i < MAX_RTP_PT; ++i) {
                rtp->current_RTP_PT[i].isAstFormat = 0;
                rtp->current_RTP_PT[i].code = 0;
        }

        rtp->rtp_lookup_code_cache_isAstFormat = 0;
        rtp->rtp_lookup_code_cache_code = 0;
        rtp->rtp_lookup_code_cache_result = 0;

        rtp_bridge_unlock(rtp);
}

void ast_rtp_pt_default(struct ast_rtp* rtp) 
{
        int i;

        rtp_bridge_lock(rtp);

        /* Initialize to default payload types */
        for (i = 0; i < MAX_RTP_PT; ++i) {
                rtp->current_RTP_PT[i].isAstFormat = static_RTP_PT[i].isAstFormat;
                rtp->current_RTP_PT[i].code = static_RTP_PT[i].code;
        }

        rtp->rtp_lookup_code_cache_isAstFormat = 0;
        rtp->rtp_lookup_code_cache_code = 0;
        rtp->rtp_lookup_code_cache_result = 0;

        rtp_bridge_unlock(rtp);
}

void ast_rtp_pt_copy(struct ast_rtp *dest, struct ast_rtp *src)
{
        unsigned int i;

        rtp_bridge_lock(dest);
        rtp_bridge_lock(src);

        for (i=0; i < MAX_RTP_PT; ++i) {
                dest->current_RTP_PT[i].isAstFormat = 
                        src->current_RTP_PT[i].isAstFormat;
                dest->current_RTP_PT[i].code = 
                        src->current_RTP_PT[i].code; 
        }
        dest->rtp_lookup_code_cache_isAstFormat = 0;
        dest->rtp_lookup_code_cache_code = 0;
        dest->rtp_lookup_code_cache_result = 0;

        rtp_bridge_unlock(src);
        rtp_bridge_unlock(dest);
}

/*! \brief Get channel driver interface structure */
static struct ast_rtp_protocol *get_proto(struct ast_channel *chan)
{
        struct ast_rtp_protocol *cur = NULL;

        AST_RWLIST_RDLOCK(&protos);
        AST_RWLIST_TRAVERSE(&protos, cur, list) {
                if (cur->type == chan->tech->type)
                        break;
        }
        AST_RWLIST_UNLOCK(&protos);

        return cur;
}

int ast_rtp_early_bridge(struct ast_channel *c0, struct ast_channel *c1)
{
        // dest = c0, src = c1
        struct ast_rtp *destp = NULL, *srcp = NULL;             /* Audio RTP Channels */
        struct ast_rtp *vdestp = NULL, *vsrcp = NULL;           /* Video RTP channels */
        struct ast_rtp *tdestp = NULL, *tsrcp = NULL;           /* Text RTP channels */
        struct ast_rtp_protocol *destpr = NULL, *srcpr = NULL;
        enum ast_rtp_get_result audio_dest_res = AST_RTP_GET_FAILED, video_dest_res = AST_RTP_GET_FAILED, text_dest_res = AST_RTP_GET_FAILED;
        enum ast_rtp_get_result audio_src_res = AST_RTP_GET_FAILED, video_src_res = AST_RTP_GET_FAILED, text_src_res = AST_RTP_GET_FAILED;
        int srccodec, destcodec, nat_active = 0;

        /* Lock channels */
        ast_channel_lock(c0);
        if (c1) {
                while (ast_channel_trylock(c1)) {
                        ast_channel_unlock(c0);
                        usleep(1);
                        ast_channel_lock(c0);
                }
        }

        /* Find channel driver interfaces */
        destpr = get_proto(c0);
        if (c1)
                srcpr = get_proto(c1);
        if (!destpr) {
                ast_debug(1, "Channel '%s' has no RTP, not doing anything\n", c0->name);
                ast_channel_unlock(c0);
                if (c1)
                        ast_channel_unlock(c1);
                return -1;
        }
        if (!srcpr) {
                ast_debug(1, "Channel '%s' has no RTP, not doing anything\n", c1 ? c1->name : "<unspecified>");
                ast_channel_unlock(c0);
                if (c1)
                        ast_channel_unlock(c1);
                return -1;
        }

        /* Get audio, video  and text interface (if native bridge is possible) */
        audio_dest_res = destpr->get_rtp_info(c0, &destp);
        video_dest_res = destpr->get_vrtp_info ? destpr->get_vrtp_info(c0, &vdestp) : AST_RTP_GET_FAILED;
        text_dest_res = destpr->get_trtp_info ? destpr->get_trtp_info(c0, &tdestp) : AST_RTP_GET_FAILED;
        if (srcpr) {
                audio_src_res = srcpr->get_rtp_info(c1, &srcp);
                video_src_res = srcpr->get_vrtp_info ? srcpr->get_vrtp_info(c1, &vsrcp) : AST_RTP_GET_FAILED;
                text_src_res = srcpr->get_trtp_info ? srcpr->get_trtp_info(c1, &tsrcp) : AST_RTP_GET_FAILED;
        }

        /* Check if bridge is still possible (In SIP canreinvite=no stops this, like NAT) */
        if (audio_dest_res != AST_RTP_TRY_NATIVE) {
                /* Somebody doesn't want to play... */
                ast_channel_unlock(c0);
                if (c1)
                        ast_channel_unlock(c1);
                return -1;
        }
        if (audio_src_res == AST_RTP_TRY_NATIVE && srcpr->get_codec)
                srccodec = srcpr->get_codec(c1);
        else
                srccodec = 0;
        if (audio_dest_res == AST_RTP_TRY_NATIVE && destpr->get_codec)
                destcodec = destpr->get_codec(c0);
        else
                destcodec = 0;
        /* Ensure we have at least one matching codec */
        if (!(srccodec & destcodec)) {
                ast_channel_unlock(c0);
                if (c1)
                        ast_channel_unlock(c1);
                return 0;
        }
        /* Consider empty media as non-existant */
        if (audio_src_res == AST_RTP_TRY_NATIVE && !srcp->them.sin_addr.s_addr)
                srcp = NULL;
        if (srcp && (srcp->nat || ast_test_flag(srcp, FLAG_NAT_ACTIVE)))
                nat_active = 1;
        /* Bridge media early */
        if (destpr->set_rtp_peer(c0, srcp, vsrcp, tsrcp, srccodec, nat_active))
                ast_log(LOG_WARNING, "Channel '%s' failed to setup early bridge to '%s'\n", c0->name, c1 ? c1->name : "<unspecified>");
        ast_channel_unlock(c0);
        if (c1)
                ast_channel_unlock(c1);
        ast_debug(1, "Setting early bridge SDP of '%s' with that of '%s'\n", c0->name, c1 ? c1->name : "<unspecified>");
        return 0;
}

int ast_rtp_make_compatible(struct ast_channel *dest, struct ast_channel *src, int media)
{
        struct ast_rtp *destp = NULL, *srcp = NULL;             /* Audio RTP Channels */
        struct ast_rtp *vdestp = NULL, *vsrcp = NULL;           /* Video RTP channels */
        struct ast_rtp *tdestp = NULL, *tsrcp = NULL;           /* Text RTP channels */
        struct ast_rtp_protocol *destpr = NULL, *srcpr = NULL;
        enum ast_rtp_get_result audio_dest_res = AST_RTP_GET_FAILED, video_dest_res = AST_RTP_GET_FAILED, text_dest_res = AST_RTP_GET_FAILED;
        enum ast_rtp_get_result audio_src_res = AST_RTP_GET_FAILED, video_src_res = AST_RTP_GET_FAILED, text_src_res = AST_RTP_GET_FAILED; 
        int srccodec, destcodec;

        /* Lock channels */
        ast_channel_lock(dest);
        while (ast_channel_trylock(src)) {
                ast_channel_unlock(dest);
                usleep(1);
                ast_channel_lock(dest);
        }

        /* Find channel driver interfaces */
        if (!(destpr = get_proto(dest))) {
                ast_debug(1, "Channel '%s' has no RTP, not doing anything\n", dest->name);
                ast_channel_unlock(dest);
                ast_channel_unlock(src);
                return 0;
        }
        if (!(srcpr = get_proto(src))) {
                ast_debug(1, "Channel '%s' has no RTP, not doing anything\n", src->name);
                ast_channel_unlock(dest);
                ast_channel_unlock(src);
                return 0;
        }

        /* Get audio and video interface (if native bridge is possible) */
        audio_dest_res = destpr->get_rtp_info(dest, &destp);
        video_dest_res = destpr->get_vrtp_info ? destpr->get_vrtp_info(dest, &vdestp) : AST_RTP_GET_FAILED;
        text_dest_res = destpr->get_trtp_info ? destpr->get_trtp_info(dest, &tdestp) : AST_RTP_GET_FAILED;
        audio_src_res = srcpr->get_rtp_info(src, &srcp);
        video_src_res = srcpr->get_vrtp_info ? srcpr->get_vrtp_info(src, &vsrcp) : AST_RTP_GET_FAILED;
        text_src_res = srcpr->get_trtp_info ? srcpr->get_trtp_info(src, &tsrcp) : AST_RTP_GET_FAILED;

        /* Ensure we have at least one matching codec */
        if (srcpr->get_codec)
                srccodec = srcpr->get_codec(src);
        else
                srccodec = 0;
        if (destpr->get_codec)
                destcodec = destpr->get_codec(dest);
        else
                destcodec = 0;

        /* Check if bridge is still possible (In SIP canreinvite=no stops this, like NAT) */
        if (audio_dest_res != AST_RTP_TRY_NATIVE || audio_src_res != AST_RTP_TRY_NATIVE || !(srccodec & destcodec)) {
                /* Somebody doesn't want to play... */
                ast_channel_unlock(dest);
                ast_channel_unlock(src);
                return 0;
        }
        ast_rtp_pt_copy(destp, srcp);
        if (vdestp && vsrcp)
                ast_rtp_pt_copy(vdestp, vsrcp);
        if (tdestp && tsrcp)
                ast_rtp_pt_copy(tdestp, tsrcp);
        if (media) {
                /* Bridge early */
                if (destpr->set_rtp_peer(dest, srcp, vsrcp, tsrcp, srccodec, ast_test_flag(srcp, FLAG_NAT_ACTIVE)))
                        ast_log(LOG_WARNING, "Channel '%s' failed to setup early bridge to '%s'\n", dest->name, src->name);
        }
        ast_channel_unlock(dest);
        ast_channel_unlock(src);
        ast_debug(1, "Seeded SDP of '%s' with that of '%s'\n", dest->name, src->name);
        return 1;
}

/*! \brief  Make a note of a RTP payload type that was seen in a SDP "m=" line.
 * By default, use the well-known value for this type (although it may 
 * still be set to a different value by a subsequent "a=rtpmap:" line)
 */
void ast_rtp_set_m_type(struct ast_rtp* rtp, int pt) 
{
        if (pt < 0 || pt > MAX_RTP_PT || static_RTP_PT[pt].code == 0) 
                return; /* bogus payload type */

        rtp_bridge_lock(rtp);
        rtp->current_RTP_PT[pt] = static_RTP_PT[pt];
        rtp_bridge_unlock(rtp);
} 

/*! \brief Make a note of a RTP payload type (with MIME type) that was seen in
 * an SDP "a=rtpmap:" line.
 */
void ast_rtp_set_rtpmap_type(struct ast_rtp *rtp, int pt,
                             char *mimeType, char *mimeSubtype,
                             enum ast_rtp_options options)
{
        unsigned int i;

        if (pt < 0 || pt > MAX_RTP_PT) 
                return; /* bogus payload type */
        
        rtp_bridge_lock(rtp);

        for (i = 0; i < sizeof(mimeTypes)/sizeof(mimeTypes[0]); ++i) {
                if (strcasecmp(mimeSubtype, mimeTypes[i].subtype) == 0 &&
                    strcasecmp(mimeType, mimeTypes[i].type) == 0) {
                        rtp->current_RTP_PT[pt] = mimeTypes[i].payloadType;
                        if ((mimeTypes[i].payloadType.code == AST_FORMAT_G726) &&
                            mimeTypes[i].payloadType.isAstFormat &&
                            (options & AST_RTP_OPT_G726_NONSTANDARD))
                                rtp->current_RTP_PT[pt].code = AST_FORMAT_G726_AAL2;
                        break;
                }
        }

        rtp_bridge_unlock(rtp);

        return;
} 

/*! \brief Return the union of all of the codecs that were set by rtp_set...() calls 
 * They're returned as two distinct sets: AST_FORMATs, and AST_RTPs */
void ast_rtp_get_current_formats(struct ast_rtp* rtp,
                                 int* astFormats, int* nonAstFormats)
{
        int pt;
        
        rtp_bridge_lock(rtp);
        
        *astFormats = *nonAstFormats = 0;
        for (pt = 0; pt < MAX_RTP_PT; ++pt) {
                if (rtp->current_RTP_PT[pt].isAstFormat) {
                        *astFormats |= rtp->current_RTP_PT[pt].code;
                } else {
                        *nonAstFormats |= rtp->current_RTP_PT[pt].code;
                }
        }

        rtp_bridge_unlock(rtp);
        
        return;
}

struct rtpPayloadType ast_rtp_lookup_pt(struct ast_rtp* rtp, int pt) 
{
        struct rtpPayloadType result;

        result.isAstFormat = result.code = 0;

        if (pt < 0 || pt > MAX_RTP_PT) 
                return result; /* bogus payload type */

        /* Start with negotiated codecs */
        rtp_bridge_lock(rtp);
        result = rtp->current_RTP_PT[pt];
        rtp_bridge_unlock(rtp);

        /* If it doesn't exist, check our static RTP type list, just in case */
        if (!result.code) 
                result = static_RTP_PT[pt];

        return result;
}

/*! \brief Looks up an RTP code out of our *static* outbound list */
int ast_rtp_lookup_code(struct ast_rtp* rtp, const int isAstFormat, const int code)
{
        int pt = 0;

        rtp_bridge_lock(rtp);

        if (isAstFormat == rtp->rtp_lookup_code_cache_isAstFormat &&
                code == rtp->rtp_lookup_code_cache_code) {
                /* Use our cached mapping, to avoid the overhead of the loop below */
                pt = rtp->rtp_lookup_code_cache_result;
                rtp_bridge_unlock(rtp);
                return pt;
        }

        /* Check the dynamic list first */
        for (pt = 0; pt < MAX_RTP_PT; ++pt) {
                if (rtp->current_RTP_PT[pt].code == code && rtp->current_RTP_PT[pt].isAstFormat == isAstFormat) {
                        rtp->rtp_lookup_code_cache_isAstFormat = isAstFormat;
                        rtp->rtp_lookup_code_cache_code = code;
                        rtp->rtp_lookup_code_cache_result = pt;
                        rtp_bridge_unlock(rtp);
                        return pt;
                }
        }

        /* Then the static list */
        for (pt = 0; pt < MAX_RTP_PT; ++pt) {
                if (static_RTP_PT[pt].code == code && static_RTP_PT[pt].isAstFormat == isAstFormat) {
                        rtp->rtp_lookup_code_cache_isAstFormat = isAstFormat;
                        rtp->rtp_lookup_code_cache_code = code;
                        rtp->rtp_lookup_code_cache_result = pt;
                        rtp_bridge_unlock(rtp);
                        return pt;
                }
        }

        rtp_bridge_unlock(rtp);

        return -1;
}

const char *ast_rtp_lookup_mime_subtype(const int isAstFormat, const int code,
                                  enum ast_rtp_options options)
{
        unsigned int i;

        for (i = 0; i < sizeof(mimeTypes)/sizeof(mimeTypes[0]); ++i) {
                if ((mimeTypes[i].payloadType.code == code) && (mimeTypes[i].payloadType.isAstFormat == isAstFormat)) {
                        if (isAstFormat &&
                            (code == AST_FORMAT_G726_AAL2) &&
                            (options & AST_RTP_OPT_G726_NONSTANDARD))
                                return "G726-32";
                        else
                                return mimeTypes[i].subtype;
                }
        }

        return "";
}

char *ast_rtp_lookup_mime_multiple(char *buf, size_t size, const int capability,
                                   const int isAstFormat, enum ast_rtp_options options)
{
        int format;
        unsigned len;
        char *end = buf;
        char *start = buf;

        if (!buf || !size)
                return NULL;

        snprintf(end, size, "0x%x (", capability);

        len = strlen(end);
        end += len;
        size -= len;
        start = end;

        for (format = 1; format < AST_RTP_MAX; format <<= 1) {
                if (capability & format) {
                        const char *name = ast_rtp_lookup_mime_subtype(isAstFormat, format, options);

                        snprintf(end, size, "%s|", name);
                        len = strlen(end);
                        end += len;
                        size -= len;
                }
        }

        if (start == end)
                ast_copy_string(start, "nothing)", size); 
        else if (size > 1)
                *(end -1) = ')';
        
        return buf;
}

/*! \brief Open RTP or RTCP socket for a session.
 * Print a message on failure. 
 */
static int rtp_socket(const char *type)
{
        int s = socket(AF_INET, SOCK_DGRAM, 0);
        if (s < 0) {
                if (type == NULL)
                        type = "RTP/RTCP";
                ast_log(LOG_WARNING, "Unable to allocate %s socket: %s\n", type, strerror(errno));
        } else {
                long flags = fcntl(s, F_GETFL);
                fcntl(s, F_SETFL, flags | O_NONBLOCK);
#ifdef SO_NO_CHECK
                if (nochecksums)
                        setsockopt(s, SOL_SOCKET, SO_NO_CHECK, &nochecksums, sizeof(nochecksums));
#endif
        }
        return s;
}

/*!
 * \brief Initialize a new RTCP session.
 * 
 * \returns The newly initialized RTCP session.
 */
static struct ast_rtcp *ast_rtcp_new(void)
{
        struct ast_rtcp *rtcp;

        if (!(rtcp = ast_calloc(1, sizeof(*rtcp))))
                return NULL;
        rtcp->s = rtp_socket("RTCP");
        rtcp->us.sin_family = AF_INET;
        rtcp->them.sin_family = AF_INET;

        if (rtcp->s < 0) {
                ast_free(rtcp);
                return NULL;
        }

        return rtcp;
}

/*!
 * \brief Initialize a new RTP structure.
 *
 */
void ast_rtp_new_init(struct ast_rtp *rtp)
{
#ifdef P2P_INTENSE
        ast_mutex_init(&rtp->bridge_lock);
#endif

        rtp->them.sin_family = AF_INET;
        rtp->us.sin_family = AF_INET;
        rtp->ssrc = ast_random();
        rtp->seqno = ast_random() & 0xffff;
        ast_set_flag(rtp, FLAG_HAS_DTMF);

        return;
}

struct ast_rtp *ast_rtp_new_with_bindaddr(struct sched_context *sched, struct io_context *io, int rtcpenable, int callbackmode, struct in_addr addr)
{
        struct ast_rtp *rtp;
        int x;
        int startplace;
        
        if (!(rtp = ast_calloc(1, sizeof(*rtp))))
                return NULL;

        ast_rtp_new_init(rtp);

        rtp->s = rtp_socket("RTP");
        if (rtp->s < 0)
                goto fail;
        if (sched && rtcpenable) {
                rtp->sched = sched;
                rtp->rtcp = ast_rtcp_new();
        }
        
        /*
         * Try to bind the RTP port, x, and possibly the RTCP port, x+1 as well.
         * Start from a random (even, by RTP spec) port number, and
         * iterate until success or no ports are available.
         * Note that the requirement of RTP port being even, or RTCP being the
         * next one, cannot be enforced in presence of a NAT box because the
         * mapping is not under our control.
         */
        x = (ast_random() % (rtpend-rtpstart)) + rtpstart;
        x = x & ~1;             /* make it an even number */
        startplace = x;         /* remember the starting point */
        /* this is constant across the loop */
        rtp->us.sin_addr = addr;
        if (rtp->rtcp)
                rtp->rtcp->us.sin_addr = addr;
        for (;;) {
                rtp->us.sin_port = htons(x);
                if (!bind(rtp->s, (struct sockaddr *)&rtp->us, sizeof(rtp->us))) {
                        /* bind succeeded, if no rtcp then we are done */
                        if (!rtp->rtcp)
                                break;
                        /* have rtcp, try to bind it */
                        rtp->rtcp->us.sin_port = htons(x + 1);
                        if (!bind(rtp->rtcp->s, (struct sockaddr *)&rtp->rtcp->us, sizeof(rtp->rtcp->us)))
                                break;  /* success again, we are really done */
                        /*
                         * RTCP bind failed, so close and recreate the
                         * already bound RTP socket for the next round.
                         */
                        close(rtp->s);
                        rtp->s = rtp_socket("RTP");
                        if (rtp->s < 0)
                                goto fail;
                }
                /*
                 * If we get here, there was an error in one of the bind()
                 * calls, so make sure it is nothing unexpected.
                 */
                if (errno != EADDRINUSE) {
                        /* We got an error that wasn't expected, abort! */
                        ast_log(LOG_ERROR, "Unexpected bind error: %s\n", strerror(errno));
                        goto fail;
                }
                /*
                 * One of the ports is in use. For the next iteration,
                 * increment by two and handle wraparound.
                 * If we reach the starting point, then declare failure.
                 */
                x += 2;
                if (x > rtpend)
                        x = (rtpstart + 1) & ~1;
                if (x == startplace) {
                        ast_log(LOG_ERROR, "No RTP ports remaining. Can't setup media stream for this call.\n");
                        goto fail;
                }
        }
        rtp->sched = sched;
        rtp->io = io;
        if (callbackmode) {
                rtp->ioid = ast_io_add(rtp->io, rtp->s, rtpread, AST_IO_IN, rtp);
                ast_set_flag(rtp, FLAG_CALLBACK_MODE);
        }
        ast_rtp_pt_default(rtp);
        return rtp;

fail:
        if (rtp->s >= 0)
                close(rtp->s);
        if (rtp->rtcp) {
                close(rtp->rtcp->s);
                ast_free(rtp->rtcp);
        }
        ast_free(rtp);
        return NULL;
}

struct ast_rtp *ast_rtp_new(struct sched_context *sched, struct io_context *io, int rtcpenable, int callbackmode)
{
        struct in_addr ia;

        memset(&ia, 0, sizeof(ia));
        return ast_rtp_new_with_bindaddr(sched, io, rtcpenable, callbackmode, ia);
}

int ast_rtp_setqos(struct ast_rtp *rtp, int tos, int cos)
{
        return ast_netsock_set_qos(rtp->s, tos, cos);
}

void ast_rtp_set_peer(struct ast_rtp *rtp, struct sockaddr_in *them)
{
        rtp->them.sin_port = them->sin_port;
        rtp->them.sin_addr = them->sin_addr;
        if (rtp->rtcp) {
                rtp->rtcp->them.sin_port = htons(ntohs(them->sin_port) + 1);
                rtp->rtcp->them.sin_addr = them->sin_addr;
        }
        rtp->rxseqno = 0;
}

int ast_rtp_get_peer(struct ast_rtp *rtp, struct sockaddr_in *them)
{
        if ((them->sin_family != AF_INET) ||
                (them->sin_port != rtp->them.sin_port) ||
                (them->sin_addr.s_addr != rtp->them.sin_addr.s_addr)) {
                them->sin_family = AF_INET;
                them->sin_port = rtp->them.sin_port;
                them->sin_addr = rtp->them.sin_addr;
                return 1;
        }
        return 0;
}

void ast_rtp_get_us(struct ast_rtp *rtp, struct sockaddr_in *us)
{
        *us = rtp->us;
}

struct ast_rtp *ast_rtp_get_bridged(struct ast_rtp *rtp)
{
        struct ast_rtp *bridged = NULL;

        rtp_bridge_lock(rtp);
        bridged = rtp->bridged;
        rtp_bridge_unlock(rtp);

        return bridged;
}

void ast_rtp_stop(struct ast_rtp *rtp)
{
        if (rtp->rtcp && rtp->rtcp->schedid > 0) {
                ast_sched_del(rtp->sched, rtp->rtcp->schedid);
                rtp->rtcp->schedid = -1;
        }

        memset(&rtp->them.sin_addr, 0, sizeof(rtp->them.sin_addr));
        memset(&rtp->them.sin_port, 0, sizeof(rtp->them.sin_port));
        if (rtp->rtcp) {
                memset(&rtp->rtcp->them.sin_addr, 0, sizeof(rtp->rtcp->them.sin_addr));
                memset(&rtp->rtcp->them.sin_port, 0, sizeof(rtp->rtcp->them.sin_port));
        }
        
        ast_clear_flag(rtp, FLAG_P2P_SENT_MARK);
}

void ast_rtp_reset(struct ast_rtp *rtp)
{
        memset(&rtp->rxcore, 0, sizeof(rtp->rxcore));
        memset(&rtp->txcore, 0, sizeof(rtp->txcore));
        memset(&rtp->dtmfmute, 0, sizeof(rtp->dtmfmute));
        rtp->lastts = 0;
        rtp->lastdigitts = 0;
        rtp->lastrxts = 0;
        rtp->lastividtimestamp = 0;
        rtp->lastovidtimestamp = 0;
        rtp->lastitexttimestamp = 0;
        rtp->lastotexttimestamp = 0;
        rtp->lasteventseqn = 0;
        rtp->lastevent = 0;
        rtp->lasttxformat = 0;
        rtp->lastrxformat = 0;
        rtp->dtmfcount = 0;
        rtp->dtmfsamples = 0;
        rtp->seqno = 0;
        rtp->rxseqno = 0;
}

char *ast_rtp_get_quality(struct ast_rtp *rtp, struct ast_rtp_quality *qual)
{
        /*
        *ssrc          our ssrc
        *themssrc      their ssrc
        *lp            lost packets
        *rxjitter      our calculated jitter(rx)
        *rxcount       no. received packets
        *txjitter      reported jitter of the other end
        *txcount       transmitted packets
        *rlp           remote lost packets
        *rtt           round trip time
        */

        if (qual) {
                qual->local_ssrc = rtp->ssrc;
                qual->local_lostpackets = rtp->rtcp->expected_prior - rtp->rtcp->received_prior;
                qual->local_jitter = rtp->rxjitter;
                qual->local_count = rtp->rxcount;
                qual->remote_ssrc = rtp->themssrc;
                qual->remote_lostpackets = rtp->rtcp->reported_lost;
                qual->remote_jitter = rtp->rtcp->reported_jitter / 65536.0;
                qual->remote_count = rtp->txcount;
                qual->rtt = rtp->rtcp->rtt;
        }
        snprintf(rtp->rtcp->quality, sizeof(rtp->rtcp->quality), "ssrc=%u;themssrc=%u;lp=%u;rxjitter=%f;rxcount=%u;txjitter=%f;txcount=%u;rlp=%u;rtt=%f", rtp->ssrc, rtp->themssrc, rtp->rtcp->expected_prior - rtp->rtcp->received_prior, rtp->rxjitter, rtp->rxcount, (double)rtp->rtcp->reported_jitter/65536., rtp->txcount, rtp->rtcp->reported_lost, rtp->rtcp->rtt);
        
        return rtp->rtcp->quality;
}

void ast_rtp_destroy(struct ast_rtp *rtp)
{
        if (rtcp_debug_test_addr(&rtp->them) || rtcpstats) {
                /*Print some info on the call here */
                ast_verbose("  RTP-stats\n");
                ast_verbose("* Our Receiver:\n");
                ast_verbose("  SSRC:             %u\n", rtp->themssrc);
                ast_verbose("  Received packets: %u\n", rtp->rxcount);
                ast_verbose("  Lost packets:     %u\n", rtp->rtcp->expected_prior - rtp->rtcp->received_prior);
                ast_verbose("  Jitter:           %.4f\n", rtp->rxjitter);
                ast_verbose("  Transit:          %.4f\n", rtp->rxtransit);
                ast_verbose("  RR-count:         %u\n", rtp->rtcp->rr_count);
                ast_verbose("* Our Sender:\n");
                ast_verbose("  SSRC:             %u\n", rtp->ssrc);
                ast_verbose("  Sent packets:     %u\n", rtp->txcount);
                ast_verbose("  Lost packets:     %u\n", rtp->rtcp->reported_lost);
                ast_verbose("  Jitter:           %u\n", rtp->rtcp->reported_jitter / (unsigned int)65536.0);
                ast_verbose("  SR-count:         %u\n", rtp->rtcp->sr_count);
                ast_verbose("  RTT:              %f\n", rtp->rtcp->rtt);
        }

        manager_event(EVENT_FLAG_REPORTING, "RTPReceiverStat", "SSRC: %u\r\n"
                                            "ReceivedPackets: %u\r\n"
                                            "LostPackets: %u\r\n"
                                            "Jitter: %.4f\r\n"
                                            "Transit: %.4f\r\n"
                                            "RRCount: %u\r\n",
                                            rtp->themssrc,
                                            rtp->rxcount,
                                            rtp->rtcp->expected_prior - rtp->rtcp->received_prior,
                                            rtp->rxjitter,
                                            rtp->rxtransit,
                                            rtp->rtcp->rr_count);
        manager_event(EVENT_FLAG_REPORTING, "RTPSenderStat", "SSRC: %u\r\n"
                                            "SentPackets: %u\r\n"
                                            "LostPackets: %u\r\n"
                                            "Jitter: %u\r\n"
                                            "SRCount: %u\r\n"
                                            "RTT: %f\r\n",
                                            rtp->ssrc,
                                            rtp->txcount,
                                            rtp->rtcp->reported_lost,
                                            rtp->rtcp->reported_jitter,
                                            rtp->rtcp->sr_count,
                                            rtp->rtcp->rtt);
        if (rtp->smoother)
                ast_smoother_free(rtp->smoother);
        if (rtp->ioid)
                ast_io_remove(rtp->io, rtp->ioid);
        if (rtp->s > -1)
                close(rtp->s);
        if (rtp->rtcp) {
                if (rtp->rtcp->schedid > 0)
                        ast_sched_del(rtp->sched, rtp->rtcp->schedid);
                close(rtp->rtcp->s);
                ast_free(rtp->rtcp);
                rtp->rtcp=NULL;
        }
#ifdef P2P_INTENSE
        ast_mutex_destroy(&rtp->bridge_lock);
#endif
        ast_free(rtp);
}

static unsigned int calc_txstamp(struct ast_rtp *rtp, struct timeval *delivery)
{
        struct timeval t;
        long ms;
        if (ast_tvzero(rtp->txcore)) {
                rtp->txcore = ast_tvnow();
                /* Round to 20ms for nice, pretty timestamps */
                rtp->txcore.tv_usec -= rtp->txcore.tv_usec % 20000;
        }
        /* Use previous txcore if available */
        t = (delivery && !ast_tvzero(*delivery)) ? *delivery : ast_tvnow();
        ms = ast_tvdiff_ms(t, rtp->txcore);
        if (ms < 0)
                ms = 0;
        /* Use what we just got for next time */
        rtp->txcore = t;
        return (unsigned int) ms;
}

/*! \brief Send begin frames for DTMF */
int ast_rtp_senddigit_begin(struct ast_rtp *rtp, char digit)
{
        unsigned int *rtpheader;
        int hdrlen = 12, res = 0, i = 0, payload = 0;
        char data[256];

        if ((digit <= '9') && (digit >= '0'))
                digit -= '0';
        else if (digit == '*')
                digit = 10;
        else if (digit == '#')
                digit = 11;
        else if ((digit >= 'A') && (digit <= 'D'))
                digit = digit - 'A' + 12;
        else if ((digit >= 'a') && (digit <= 'd'))
                digit = digit - 'a' + 12;
        else {
                ast_log(LOG_WARNING, "Don't know how to represent '%c'\n", digit);
                return 0;
        }

        /* If we have no peer, return immediately */    
        if (!rtp->them.sin_addr.s_addr || !rtp->them.sin_port)
                return 0;

        payload = ast_rtp_lookup_code(rtp, 0, AST_RTP_DTMF);

        rtp->dtmfmute = ast_tvadd(ast_tvnow(), ast_tv(0, 500000));
        rtp->send_duration = 160;
        
        /* Get a pointer to the header */
        rtpheader = (unsigned int *)data;
        rtpheader[0] = htonl((2 << 30) | (1 << 23) | (payload << 16) | (rtp->seqno));
        rtpheader[1] = htonl(rtp->lastdigitts);
        rtpheader[2] = htonl(rtp->ssrc); 

        for (i = 0; i < 2; i++) {
                rtpheader[3] = htonl((digit << 24) | (0xa << 16) | (rtp->send_duration));
                res = sendto(rtp->s, (void *) rtpheader, hdrlen + 4, 0, (struct sockaddr *) &rtp->them, sizeof(rtp->them));
                if (res < 0) 
                        ast_log(LOG_ERROR, "RTP Transmission error to %s:%u: %s\n",
                                ast_inet_ntoa(rtp->them.sin_addr),
                                ntohs(rtp->them.sin_port), strerror(errno));
                if (rtp_debug_test_addr(&rtp->them))
                        ast_verbose("Sent RTP DTMF packet to %s:%u (type %-2.2d, seq %-6.6u, ts %-6.6u, len %-6.6u)\n",
                                    ast_inet_ntoa(rtp->them.sin_addr),
                                    ntohs(rtp->them.sin_port), payload, rtp->seqno, rtp->lastdigitts, res - hdrlen);
                /* Increment sequence number */
                rtp->seqno++;
                /* Increment duration */
                rtp->send_duration += 160;
                /* Clear marker bit and set seqno */
                rtpheader[0] = htonl((2 << 30) | (payload << 16) | (rtp->seqno));
        }

        /* Since we received a begin, we can safely store the digit and disable any compensation */
        rtp->sending_digit = 1;
        rtp->send_digit = digit;
        rtp->send_payload = payload;

        return 0;
}

/*! \brief Send continuation frame for DTMF */
static int ast_rtp_senddigit_continuation(struct ast_rtp *rtp)
{
        unsigned int *rtpheader;
        int hdrlen = 12, res = 0;
        char data[256];

        if (!rtp->them.sin_addr.s_addr || !rtp->them.sin_port)
                return 0;

        /* Setup packet to send */
        rtpheader = (unsigned int *)data;
        rtpheader[0] = htonl((2 << 30) | (1 << 23) | (rtp->send_payload << 16) | (rtp->seqno));
        rtpheader[1] = htonl(rtp->lastdigitts);
        rtpheader[2] = htonl(rtp->ssrc);
        rtpheader[3] = htonl((rtp->send_digit << 24) | (0xa << 16) | (rtp->send_duration));
        rtpheader[0] = htonl((2 << 30) | (rtp->send_payload << 16) | (rtp->seqno));
        
        /* Transmit */
        res = sendto(rtp->s, (void *) rtpheader, hdrlen + 4, 0, (struct sockaddr *) &rtp->them, sizeof(rtp->them));
        if (res < 0)
                ast_log(LOG_ERROR, "RTP Transmission error to %s:%d: %s\n",
                        ast_inet_ntoa(rtp->them.sin_addr),
                        ntohs(rtp->them.sin_port), strerror(errno));
        if (rtp_debug_test_addr(&rtp->them))
                ast_verbose("Sent RTP DTMF packet to %s:%u (type %-2.2d, seq %-6.6u, ts %-6.6u, len %-6.6u)\n",
                            ast_inet_ntoa(rtp->them.sin_addr),
                            ntohs(rtp->them.sin_port), rtp->send_payload, rtp->seqno, rtp->lastdigitts, res - hdrlen);

        /* Increment sequence number */
        rtp->seqno++;
        /* Increment duration */
        rtp->send_duration += 160;

        return 0;
}

/*! \brief Send end packets for DTMF */
int ast_rtp_senddigit_end(struct ast_rtp *rtp, char digit)
{
        unsigned int *rtpheader;
        int hdrlen = 12, res = 0, i = 0;
        char data[256];
        
        /* If no address, then bail out */
        if (!rtp->them.sin_addr.s_addr || !rtp->them.sin_port)
                return 0;
        
        if ((digit <= '9') && (digit >= '0'))
                digit -= '0';
        else if (digit == '*')
                digit = 10;
        else if (digit == '#')
                digit = 11;
        else if ((digit >= 'A') && (digit <= 'D'))
                digit = digit - 'A' + 12;
        else if ((digit >= 'a') && (digit <= 'd'))
                digit = digit - 'a' + 12;
        else {
                ast_log(LOG_WARNING, "Don't know how to represent '%c'\n", digit);
                return 0;
        }

        rtp->dtmfmute = ast_tvadd(ast_tvnow(), ast_tv(0, 500000));

        rtpheader = (unsigned int *)data;
        rtpheader[0] = htonl((2 << 30) | (1 << 23) | (rtp->send_payload << 16) | (rtp->seqno));
        rtpheader[1] = htonl(rtp->lastdigitts);
        rtpheader[2] = htonl(rtp->ssrc);
        rtpheader[3] = htonl((digit << 24) | (0xa << 16) | (rtp->send_duration));
        /* Set end bit */
        rtpheader[3] |= htonl((1 << 23));
        rtpheader[0] = htonl((2 << 30) | (rtp->send_payload << 16) | (rtp->seqno));
        /* Send 3 termination packets */
        for (i = 0; i < 3; i++) {
                res = sendto(rtp->s, (void *) rtpheader, hdrlen + 4, 0, (struct sockaddr *) &rtp->them, sizeof(rtp->them));
                if (res < 0)
                        ast_log(LOG_ERROR, "RTP Transmission error to %s:%d: %s\n",
                                ast_inet_ntoa(rtp->them.sin_addr),
                                ntohs(rtp->them.sin_port), strerror(errno));
                if (rtp_debug_test_addr(&rtp->them))
                        ast_verbose("Sent RTP DTMF packet to %s:%u (type %-2.2d, seq %-6.6u, ts %-6.6u, len %-6.6u)\n",
                                    ast_inet_ntoa(rtp->them.sin_addr),
                                    ntohs(rtp->them.sin_port), rtp->send_payload, rtp->seqno, rtp->lastdigitts, res - hdrlen);
        }
        rtp->sending_digit = 0;
        rtp->send_digit = 0;
        /* Increment lastdigitts */
        rtp->lastdigitts += 960;
        rtp->seqno++;

        return res;
}

/*! \brief Public function: Send an H.261 fast update request, some devices need this rather than SIP XML */
int ast_rtcp_send_h261fur(void *data)
{
        struct ast_rtp *rtp = data;
        int res;

        rtp->rtcp->sendfur = 1;
        res = ast_rtcp_write(data);
        
        return res;
}

/*! \brief Send RTCP sender's report */
static int ast_rtcp_write_sr(const void *data)
{
        struct ast_rtp *rtp = (struct ast_rtp *)data;
        int res;
        int len = 0;
        struct timeval now;
        unsigned int now_lsw;
        unsigned int now_msw;
        unsigned int *rtcpheader;
        unsigned int lost;
        unsigned int extended;
        unsigned int expected;
        unsigned int expected_interval;
        unsigned int received_interval;
        int lost_interval;
        int fraction;
        struct timeval dlsr;
        char bdata[512];

        /* Commented condition is always not NULL if rtp->rtcp is not NULL */
        if (!rtp || !rtp->rtcp/* || (&rtp->rtcp->them.sin_addr == 0)*/)
                return 0;
        
        if (!rtp->rtcp->them.sin_addr.s_addr) {  /* This'll stop rtcp for this rtp session */
                ast_verbose("RTCP SR transmission error, rtcp halted\n");
                if (rtp->rtcp->schedid > 0)
                        ast_sched_del(rtp->sched, rtp->rtcp->schedid);
                rtp->rtcp->schedid = -1;
                return 0;
        }

        gettimeofday(&now, NULL);
        timeval2ntp(now, &now_msw, &now_lsw); /* fill thses ones in from utils.c*/
        rtcpheader = (unsigned int *)bdata;
        rtcpheader[1] = htonl(rtp->ssrc);               /* Our SSRC */
        rtcpheader[2] = htonl(now_msw);                 /* now, MSW. gettimeofday() + SEC_BETWEEN_1900_AND_1970*/
        rtcpheader[3] = htonl(now_lsw);                 /* now, LSW */
        rtcpheader[4] = htonl(rtp->lastts);             /* FIXME shouldn't be that, it should be now */
        rtcpheader[5] = htonl(rtp->txcount);            /* No. packets sent */
        rtcpheader[6] = htonl(rtp->txoctetcount);       /* No. bytes sent */
        len += 28;
        
        extended = rtp->cycles + rtp->lastrxseqno;
        expected = extended - rtp->seedrxseqno + 1;
        if (rtp->rxcount > expected) 
                expected += rtp->rxcount - expected;
        lost = expected - rtp->rxcount;
        expected_interval = expected - rtp->rtcp->expected_prior;
        rtp->rtcp->expected_prior = expected;
        received_interval = rtp->rxcount - rtp->rtcp->received_prior;
        rtp->rtcp->received_prior = rtp->rxcount;
        lost_interval = expected_interval - received_interval;
        if (expected_interval == 0 || lost_interval <= 0)
                fraction = 0;
        else
                fraction = (lost_interval << 8) / expected_interval;
        timersub(&now, &rtp->rtcp->rxlsr, &dlsr);
        rtcpheader[7] = htonl(rtp->themssrc);
        rtcpheader[8] = htonl(((fraction & 0xff) << 24) | (lost & 0xffffff));
        rtcpheader[9] = htonl((rtp->cycles) | ((rtp->lastrxseqno & 0xffff)));
        rtcpheader[10] = htonl((unsigned int)(rtp->rxjitter * 65536.));
        rtcpheader[11] = htonl(rtp->rtcp->themrxlsr);
        rtcpheader[12] = htonl((((dlsr.tv_sec * 1000) + (dlsr.tv_usec / 1000)) * 65536) / 1000);
        len += 24;
        
        rtcpheader[0] = htonl((2 << 30) | (1 << 24) | (RTCP_PT_SR << 16) | ((len/4)-1));

        if (rtp->rtcp->sendfur) {
                rtcpheader[13] = htonl((2 << 30) | (0 << 24) | (RTCP_PT_FUR << 16) | 1);
                rtcpheader[14] = htonl(rtp->ssrc);               /* Our SSRC */
                len += 8;
                rtp->rtcp->sendfur = 0;
        }
        
        /* Insert SDES here. Probably should make SDES text equal to mimetypes[code].type (not subtype 'cos */ 
        /* it can change mid call, and SDES can't) */
        rtcpheader[len/4]     = htonl((2 << 30) | (1 << 24) | (RTCP_PT_SDES << 16) | 2);
        rtcpheader[(len/4)+1] = htonl(rtp->ssrc);               /* Our SSRC */
        rtcpheader[(len/4)+2] = htonl(0x01 << 24);                    /* Empty for the moment */
        len += 12;
        
        res = sendto(rtp->rtcp->s, (unsigned int *)rtcpheader, len, 0, (struct sockaddr *)&rtp->rtcp->them, sizeof(rtp->rtcp->them));
        if (res < 0) {
                ast_log(LOG_ERROR, "RTCP SR transmission error to %s:%d, rtcp halted %s\n",ast_inet_ntoa(rtp->rtcp->them.sin_addr), ntohs(rtp->rtcp->them.sin_port), strerror(errno));
                if (rtp->rtcp->schedid > 0)
                        ast_sched_del(rtp->sched, rtp->rtcp->schedid);
                rtp->rtcp->schedid = -1;
                return 0;
        }
        
        /* FIXME Don't need to get a new one */
        gettimeofday(&rtp->rtcp->txlsr, NULL);
        rtp->rtcp->sr_count++;

        rtp->rtcp->lastsrtxcount = rtp->txcount;        
        
        if (rtcp_debug_test_addr(&rtp->rtcp->them)) {
                ast_verbose("* Sent RTCP SR to %s:%d\n", ast_inet_ntoa(rtp->rtcp->them.sin_addr), ntohs(rtp->rtcp->them.sin_port));
                ast_verbose("  Our SSRC: %u\n", rtp->ssrc);
                ast_verbose("  Sent(NTP): %u.%010u\n", (unsigned int)now.tv_sec, (unsigned int)now.tv_usec*4096);
                ast_verbose("  Sent(RTP): %u\n", rtp->lastts);
                ast_verbose("  Sent packets: %u\n", rtp->txcount);
                ast_verbose("  Sent octets: %u\n", rtp->txoctetcount);
                ast_verbose("  Report block:\n");
                ast_verbose("  Fraction lost: %u\n", fraction);
                ast_verbose("  Cumulative loss: %u\n", lost);
                ast_verbose("  IA jitter: %.4f\n", rtp->rxjitter);
                ast_verbose("  Their last SR: %u\n", rtp->rtcp->themrxlsr);
                ast_verbose("  DLSR: %4.4f (sec)\n\n", (double)(ntohl(rtcpheader[12])/65536.0));
        }
        manager_event(EVENT_FLAG_REPORTING, "RTCPSent", "To %s:%d\r\n"
                                            "OurSSRC: %u\r\n"
                                            "SentNTP: %u.%010u\r\n"
                                            "SentRTP: %u\r\n"
                                            "SentPackets: %u\r\n"
                                            "SentOctets: %u\r\n"
                                            "ReportBlock:\r\n"
                                            "FractionLost: %u\r\n"
                                            "CumulativeLoss: %u\r\n"
                                            "IAJitter: %.4f\r\n"
                                            "TheirLastSR: %u\r\n"
                                            "DLSR: %4.4f (sec)\r\n",
                                            ast_inet_ntoa(rtp->rtcp->them.sin_addr), ntohs(rtp->rtcp->them.sin_port),
                                            rtp->ssrc,
                                            (unsigned int)now.tv_sec, (unsigned int)now.tv_usec*4096,
                                            rtp->lastts,
                                            rtp->txcount,
                                            rtp->txoctetcount,
                                            fraction,
                                            lost,
                                            rtp->rxjitter,
                                            rtp->rtcp->themrxlsr,
                                            (double)(ntohl(rtcpheader[12])/65536.0));
        return res;
}

/*! \brief Send RTCP recipient's report */
static int ast_rtcp_write_rr(const void *data)
{
        struct ast_rtp *rtp = (struct ast_rtp *)data;
        int res;
        int len = 32;
        unsigned int lost;
        unsigned int extended;
        unsigned int expected;
        unsigned int expected_interval;
        unsigned int received_interval;
        int lost_interval;
        struct timeval now;
        unsigned int *rtcpheader;
        char bdata[1024];
        struct timeval dlsr;
        int fraction;

        if (!rtp || !rtp->rtcp || (&rtp->rtcp->them.sin_addr == 0))
                return 0;
          
        if (!rtp->rtcp->them.sin_addr.s_addr) {
                ast_log(LOG_ERROR, "RTCP RR transmission error, rtcp halted\n");
                if (rtp->rtcp->schedid > 0)
                        ast_sched_del(rtp->sched, rtp->rtcp->schedid);
                rtp->rtcp->schedid = -1;
                return 0;
        }

        extended = rtp->cycles + rtp->lastrxseqno;
        expected = extended - rtp->seedrxseqno + 1;
        lost = expected - rtp->rxcount;
        expected_interval = expected - rtp->rtcp->expected_prior;
        rtp->rtcp->expected_prior = expected;
        received_interval = rtp->rxcount - rtp->rtcp->received_prior;
        rtp->rtcp->received_prior = rtp->rxcount;
        lost_interval = expected_interval - received_interval;
        if (expected_interval == 0 || lost_interval <= 0)
                fraction = 0;
        else
                fraction = (lost_interval << 8) / expected_interval;
        gettimeofday(&now, NULL);
        timersub(&now, &rtp->rtcp->rxlsr, &dlsr);
        rtcpheader = (unsigned int *)bdata;
        rtcpheader[0] = htonl((2 << 30) | (1 << 24) | (RTCP_PT_RR << 16) | ((len/4)-1));
        rtcpheader[1] = htonl(rtp->ssrc);
        rtcpheader[2] = htonl(rtp->themssrc);
        rtcpheader[3] = htonl(((fraction & 0xff) << 24) | (lost & 0xffffff));
        rtcpheader[4] = htonl((rtp->cycles) | ((rtp->lastrxseqno & 0xffff)));
        rtcpheader[5] = htonl((unsigned int)(rtp->rxjitter * 65536.));
        rtcpheader[6] = htonl(rtp->rtcp->themrxlsr);
        rtcpheader[7] = htonl((((dlsr.tv_sec * 1000) + (dlsr.tv_usec / 1000)) * 65536) / 1000);

        if (rtp->rtcp->sendfur) {
                rtcpheader[8] = htonl((2 << 30) | (0 << 24) | (RTCP_PT_FUR << 16) | 1); /* Header from page 36 in RFC 3550 */
                rtcpheader[9] = htonl(rtp->ssrc);               /* Our SSRC */
                len += 8;
                rtp->rtcp->sendfur = 0;
        }

        /*! \note Insert SDES here. Probably should make SDES text equal to mimetypes[code].type (not subtype 'cos 
        it can change mid call, and SDES can't) */
        rtcpheader[len/4]     = htonl((2 << 30) | (1 << 24) | (RTCP_PT_SDES << 16) | 2);
        rtcpheader[(len/4)+1] = htonl(rtp->ssrc);               /* Our SSRC */
        rtcpheader[(len/4)+2] = htonl(0x01 << 24);              /* Empty for the moment */
        len += 12;
        
        res = sendto(rtp->rtcp->s, (unsigned int *)rtcpheader, len, 0, (struct sockaddr *)&rtp->rtcp->them, sizeof(rtp->rtcp->them));

        if (res < 0) {
                ast_log(LOG_ERROR, "RTCP RR transmission error, rtcp halted: %s\n",strerror(errno));
                /* Remove the scheduler */
                if (rtp->rtcp->schedid > 0)
                        ast_sched_del(rtp->sched, rtp->rtcp->schedid);
                rtp->rtcp->schedid = -1;
                return 0;
        }

        rtp->rtcp->rr_count++;

        if (rtcp_debug_test_addr(&rtp->rtcp->them)) {
                ast_verbose("\n* Sending RTCP RR to %s:%d\n"
                        "  Our SSRC: %u\nTheir SSRC: %u\niFraction lost: %d\nCumulative loss: %u\n" 
                        "  IA jitter: %.4f\n" 
                        "  Their last SR: %u\n" 
                        "  DLSR: %4.4f (sec)\n\n",
                        ast_inet_ntoa(rtp->rtcp->them.sin_addr),
                        ntohs(rtp->rtcp->them.sin_port),
                        rtp->ssrc, rtp->themssrc, fraction, lost,
                        rtp->rxjitter,
                        rtp->rtcp->themrxlsr,
                        (double)(ntohl(rtcpheader[7])/65536.0));
        }

        return res;
}

/*! \brief Write and RTCP packet to the far end
 * \note Decide if we are going to send an SR (with Reception Block) or RR 
 * RR is sent if we have not sent any rtp packets in the previous interval */
static int ast_rtcp_write(const void *data)
{
        struct ast_rtp *rtp = (struct ast_rtp *)data;
        int res;
        
        if (!rtp || !rtp->rtcp)
                return 0;

        if (rtp->txcount > rtp->rtcp->lastsrtxcount)
                res = ast_rtcp_write_sr(data);
        else
                res = ast_rtcp_write_rr(data);
        
        return res;
}

/*! \brief generate comfort noice (CNG) */
int ast_rtp_sendcng(struct ast_rtp *rtp, int level)
{
        unsigned int *rtpheader;
        int hdrlen = 12;
        int res;
        int payload;
        char data[256];
        level = 127 - (level & 0x7f);
        payload = ast_rtp_lookup_code(rtp, 0, AST_RTP_CN);

        /* If we have no peer, return immediately */    
        if (!rtp->them.sin_addr.s_addr)
                return 0;

        rtp->dtmfmute = ast_tvadd(ast_tvnow(), ast_tv(0, 500000));

        /* Get a pointer to the header */
        rtpheader = (unsigned int *)data;
        rtpheader[0] = htonl((2 << 30) | (1 << 23) | (payload << 16) | (rtp->seqno++));
        rtpheader[1] = htonl(rtp->lastts);
        rtpheader[2] = htonl(rtp->ssrc); 
        data[12] = level;
        if (rtp->them.sin_port && rtp->them.sin_addr.s_addr) {
                res = sendto(rtp->s, (void *)rtpheader, hdrlen + 1, 0, (struct sockaddr *)&rtp->them, sizeof(rtp->them));
                if (res <0) 
                        ast_log(LOG_ERROR, "RTP Comfort Noise Transmission error to %s:%d: %s\n", ast_inet_ntoa(rtp->them.sin_addr), ntohs(rtp->them.sin_port), strerror(errno));
                if (rtp_debug_test_addr(&rtp->them))
                        ast_verbose("Sent Comfort Noise RTP packet to %s:%u (type %d, seq %u, ts %u, len %d)\n"
                                        , ast_inet_ntoa(rtp->them.sin_addr), ntohs(rtp->them.sin_port), payload, rtp->seqno, rtp->lastts,res - hdrlen);            
                   
        }
        return 0;
}

/*! \brief Write RTP packet with audio or video media frames into UDP packet */
static int ast_rtp_raw_write(struct ast_rtp *rtp, struct ast_frame *f, int codec)
{
        unsigned char *rtpheader;
        int hdrlen = 12;
        int res;
        unsigned int ms;
        int pred;
        int mark = 0;

        ms = calc_txstamp(rtp, &f->delivery);
        /* Default prediction */
        if (f->subclass < AST_FORMAT_MAX_AUDIO) {
                pred = rtp->lastts + f->samples;

                /* Re-calculate last TS */
                rtp->lastts = rtp->lastts + ms * 8;
                if (ast_tvzero(f->delivery)) {
                        /* If this isn't an absolute delivery time, Check if it is close to our prediction, 
                           and if so, go with our prediction */
                        if (abs(rtp->lastts - pred) < MAX_TIMESTAMP_SKEW)
                                rtp->lastts = pred;
                        else {
                                ast_debug(3, "Difference is %d, ms is %d\n", abs(rtp->lastts - pred), ms);
                                mark = 1;
                        }
                }
        } else if(f->subclass < AST_FORMAT_MAX_VIDEO) {
                mark = f->subclass & 0x1;
                pred = rtp->lastovidtimestamp + f->samples;
                /* Re-calculate last TS */
                rtp->lastts = rtp->lastts + ms * 90;
                /* If it's close to our prediction, go for it */
                if (ast_tvzero(f->delivery)) {
                        if (abs(rtp->lastts - pred) < 7200) {
                                rtp->lastts = pred;
                                rtp->lastovidtimestamp += f->samples;
                        } else {
                                ast_debug(3, "Difference is %d, ms is %d (%d), pred/ts/samples %d/%d/%d\n", abs(rtp->lastts - pred), ms, ms * 90, rtp->lastts, pred, f->samples);
                                rtp->lastovidtimestamp = rtp->lastts;
                        }
                }
        } else {
                pred = rtp->lastotexttimestamp + f->samples;
                /* Re-calculate last TS */
                rtp->lastts = rtp->lastts + ms * 90;
                /* If it's close to our prediction, go for it */
                if (ast_tvzero(f->delivery)) {
                        if (abs(rtp->lastts - pred) < 7200) {
                                rtp->lastts = pred;
                                rtp->lastotexttimestamp += f->samples;
                        } else {
                                ast_debug(3, "Difference is %d, ms is %d (%d), pred/ts/samples %d/%d/%d\n", abs(rtp->lastts - pred), ms, ms * 90, rtp->lastts, pred, f->samples);
                                rtp->lastotexttimestamp = rtp->lastts;
                        }
                }
        }
        /* If the timestamp for non-digit packets has moved beyond the timestamp
           for digits, update the digit timestamp.
        */
        if (rtp->lastts > rtp->lastdigitts)
                rtp->lastdigitts = rtp->lastts;

        if (f->has_timing_info)
                rtp->lastts = f->ts * 8;

        /* Get a pointer to the header */
        rtpheader = (unsigned char *)(f->data - hdrlen);

        put_unaligned_uint32(rtpheader, htonl((2 << 30) | (codec << 16) | (rtp->seqno) | (mark << 23)));
        put_unaligned_uint32(rtpheader + 4, htonl(rtp->lastts));
        put_unaligned_uint32(rtpheader + 8, htonl(rtp->ssrc)); 

        if (rtp->them.sin_port && rtp->them.sin_addr.s_addr) {
                res = sendto(rtp->s, (void *)rtpheader, f->datalen + hdrlen, 0, (struct sockaddr *)&rtp->them, sizeof(rtp->them));
                if (res <0) {
                        if (!rtp->nat || (rtp->nat && (ast_test_flag(rtp, FLAG_NAT_ACTIVE) == FLAG_NAT_ACTIVE))) {
                                ast_debug(1, "RTP Transmission error of packet %d to %s:%d: %s\n", rtp->seqno, ast_inet_ntoa(rtp->them.sin_addr), ntohs(rtp->them.sin_port), strerror(errno));
                        } else if (((ast_test_flag(rtp, FLAG_NAT_ACTIVE) == FLAG_NAT_INACTIVE) || rtpdebug) && !ast_test_flag(rtp, FLAG_NAT_INACTIVE_NOWARN)) {
                                /* Only give this error message once if we are not RTP debugging */
                                if (option_debug || rtpdebug)
                                        ast_debug(0, "RTP NAT: Can't write RTP to private address %s:%d, waiting for other end to send audio...\n", ast_inet_ntoa(rtp->them.sin_addr), ntohs(rtp->them.sin_port));
                                ast_set_flag(rtp, FLAG_NAT_INACTIVE_NOWARN);
                        }
                } else {
                        rtp->txcount++;
                        rtp->txoctetcount +=(res - hdrlen);
                        
                        if (rtp->rtcp && rtp->rtcp->schedid < 1) 
                            rtp->rtcp->schedid = ast_sched_add(rtp->sched, ast_rtcp_calc_interval(rtp), ast_rtcp_write, rtp);
                }
                                
                if (rtp_debug_test_addr(&rtp->them))
                        ast_verbose("Sent RTP packet to      %s:%u (type %-2.2d, seq %-6.6u, ts %-6.6u, len %-6.6u)\n",
                                        ast_inet_ntoa(rtp->them.sin_addr), ntohs(rtp->them.sin_port), codec, rtp->seqno, rtp->lastts,res - hdrlen);
        }

        rtp->seqno++;

        return 0;
}

int ast_rtp_codec_setpref(struct ast_rtp *rtp, struct ast_codec_pref *prefs)
{
        int x;
        for (x = 0; x < 32; x++) {  /* Ugly way */
                rtp->pref.order[x] = prefs->order[x];
                rtp->pref.framing[x] = prefs->framing[x];
        }
        if (rtp->smoother)
                ast_smoother_free(rtp->smoother);
        rtp->smoother = NULL;
        return 0;
}

struct ast_codec_pref *ast_rtp_codec_getpref(struct ast_rtp *rtp)
{
        return &rtp->pref;
}

int ast_rtp_codec_getformat(int pt)
{
        if (pt < 0 || pt > MAX_RTP_PT)
                return 0; /* bogus payload type */

        if (static_RTP_PT[pt].isAstFormat)
                return static_RTP_PT[pt].code;
        else
                return 0;
}

int ast_rtp_write(struct ast_rtp *rtp, struct ast_frame *_f)
{
        struct ast_frame *f;
        int codec;
        int hdrlen = 12;
        int subclass;
        

        /* If we have no peer, return immediately */    
        if (!rtp->them.sin_addr.s_addr)
                return 0;

        /* If there is no data length, return immediately */
        if (!_f->datalen) 
                return 0;
        
        /* Make sure we have enough space for RTP header */
        if ((_f->frametype != AST_FRAME_VOICE) && (_f->frametype != AST_FRAME_VIDEO) && (_f->frametype != AST_FRAME_TEXT)) {
                ast_log(LOG_WARNING, "RTP can only send voice, video and text\n");
                return -1;
        }

        /* The bottom bit of a video subclass contains the marker bit */
        subclass = _f->subclass;
        if (_f->frametype == AST_FRAME_VIDEO)
                subclass &= ~0x1;

        codec = ast_rtp_lookup_code(rtp, 1, subclass);
        if (codec < 0) {
                ast_log(LOG_WARNING, "Don't know how to send format %s packets with RTP\n", ast_getformatname(_f->subclass));
                return -1;
        }

        if (rtp->lasttxformat != subclass) {
                /* New format, reset the smoother */
                ast_debug(1, "Ooh, format changed from %s to %s\n", ast_getformatname(rtp->lasttxformat), ast_getformatname(subclass));
                rtp->lasttxformat = subclass;
                if (rtp->smoother)
                        ast_smoother_free(rtp->smoother);
                rtp->smoother = NULL;
        }

        if (!rtp->smoother && subclass != AST_FORMAT_SPEEX) {
                struct ast_format_list fmt = ast_codec_pref_getsize(&rtp->pref, subclass);
                if (fmt.inc_ms) { /* if codec parameters is set / avoid division by zero */
                        if (!(rtp->smoother = ast_smoother_new((fmt.cur_ms * fmt.fr_len) / fmt.inc_ms))) {
                                ast_log(LOG_WARNING, "Unable to create smoother: format: %d ms: %d len: %d\n", subclass, fmt.cur_ms, ((fmt.cur_ms * fmt.fr_len) / fmt.inc_ms));
                                return -1;
                        }
                        if (fmt.flags)
                                ast_smoother_set_flags(rtp->smoother, fmt.flags);
                        ast_debug(1, "Created smoother: format: %d ms: %d len: %d\n", subclass, fmt.cur_ms, ((fmt.cur_ms * fmt.fr_len) / fmt.inc_ms));
                }
        }
        if (rtp->smoother) {
                if (ast_smoother_test_flag(rtp->smoother, AST_SMOOTHER_FLAG_BE)) {
                        ast_smoother_feed_be(rtp->smoother, _f);
                } else {
                        ast_smoother_feed(rtp->smoother, _f);
                }

                while ((f = ast_smoother_read(rtp->smoother)) && (f->data))
                        ast_rtp_raw_write(rtp, f, codec);
        } else {
                /* Don't buffer outgoing frames; send them one-per-packet: */
                if (_f->offset < hdrlen) 
                        f = ast_frdup(_f);      /*! \bug XXX this might never be free'd. Why do we do this? */
                else
                        f = _f;
                if (f->data)
                        ast_rtp_raw_write(rtp, f, codec);
                if (f != _f)
                        ast_frfree(f);
        }
                
        return 0;
}

/*! \brief Unregister interface to channel driver */
void ast_rtp_proto_unregister(struct ast_rtp_protocol *proto)
{
        AST_RWLIST_WRLOCK(&protos);
        AST_RWLIST_REMOVE(&protos, proto, list);
        AST_RWLIST_UNLOCK(&protos);
}

/*! \brief Register interface to channel driver */
int ast_rtp_proto_register(struct ast_rtp_protocol *proto)
{
        struct ast_rtp_protocol *cur;

        AST_RWLIST_WRLOCK(&protos);
        AST_RWLIST_TRAVERSE(&protos, cur, list) {       
                if (!strcmp(cur->type, proto->type)) {
                        ast_log(LOG_WARNING, "Tried to register same protocol '%s' twice\n", cur->type);
                        AST_RWLIST_UNLOCK(&protos);
                        return -1;
                }
        }
        AST_RWLIST_INSERT_HEAD(&protos, proto, list);
        AST_RWLIST_UNLOCK(&protos);
        
        return 0;
}

/*! \brief Bridge loop for true native bridge (reinvite) */
static enum ast_bridge_result bridge_native_loop(struct ast_channel *c0, struct ast_channel *c1, struct ast_rtp *p0, struct ast_rtp *p1, struct ast_rtp *vp0, struct ast_rtp *vp1, struct ast_rtp *tp0, struct ast_rtp *tp1, struct ast_rtp_protocol *pr0, struct ast_rtp_protocol *pr1, int codec0, int codec1, int timeoutms, int flags, struct ast_frame **fo, struct ast_channel **rc, void *pvt0, void *pvt1)
{
        struct ast_frame *fr = NULL;
        struct ast_channel *who = NULL, *other = NULL, *cs[3] = {NULL, };
        int oldcodec0 = codec0, oldcodec1 = codec1;
        struct sockaddr_in ac1 = {0,}, vac1 = {0,}, tac1 = {0,}, ac0 = {0,}, vac0 = {0,}, tac0 = {0,};
        struct sockaddr_in t1 = {0,}, vt1 = {0,}, tt1 = {0,}, t0 = {0,}, vt0 = {0,}, tt0 = {0,};
        
        /* Set it up so audio goes directly between the two endpoints */

        /* Test the first channel */
        if (!(pr0->set_rtp_peer(c0, p1, vp1, tp1, codec1, ast_test_flag(p1, FLAG_NAT_ACTIVE)))) {
                ast_rtp_get_peer(p1, &ac1);
                if (vp1)
                        ast_rtp_get_peer(vp1, &vac1);
                if (tp1)
                        ast_rtp_get_peer(tp1, &tac1);
        } else
                ast_log(LOG_WARNING, "Channel '%s' failed to talk to '%s'\n", c0->name, c1->name);
        
        /* Test the second channel */
        if (!(pr1->set_rtp_peer(c1, p0, vp0, tp0, codec0, ast_test_flag(p0, FLAG_NAT_ACTIVE)))) {
                ast_rtp_get_peer(p0, &ac0);
                if (vp0)
                        ast_rtp_get_peer(vp0, &vac0);
                if (tp0)
                        ast_rtp_get_peer(tp0, &tac0);
        } else
                ast_log(LOG_WARNING, "Channel '%s' failed to talk to '%s'\n", c1->name, c0->name);

        /* Now we can unlock and move into our loop */
        ast_channel_unlock(c0);
        ast_channel_unlock(c1);

        ast_poll_channel_add(c0, c1);

        /* Throw our channels into the structure and enter the loop */
        cs[0] = c0;
        cs[1] = c1;
        cs[2] = NULL;
        for (;;) {
                /* Check if anything changed */
                if ((c0->tech_pvt != pvt0) ||
                    (c1->tech_pvt != pvt1) ||
                    (c0->masq || c0->masqr || c1->masq || c1->masqr)) {
                        ast_debug(1, "Oooh, something is weird, backing out\n");
                        if (c0->tech_pvt == pvt0)
                                if (pr0->set_rtp_peer(c0, NULL, NULL, NULL, 0, 0))
                                        ast_log(LOG_WARNING, "Channel '%s' failed to break RTP bridge\n", c0->name);
                        if (c1->tech_pvt == pvt1)
                                if (pr1->set_rtp_peer(c1, NULL, NULL, NULL, 0, 0))
                                        ast_log(LOG_WARNING, "Channel '%s' failed to break RTP bridge\n", c1->name);
                        ast_poll_channel_del(c0, c1);
                        return AST_BRIDGE_RETRY;
                }

                /* Check if they have changed their address */
                ast_rtp_get_peer(p1, &t1);
                if (vp1)
                        ast_rtp_get_peer(vp1, &vt1);
                if (tp1)
                        ast_rtp_get_peer(tp1, &tt1);
                if (pr1->get_codec)
                        codec1 = pr1->get_codec(c1);
                ast_rtp_get_peer(p0, &t0);
                if (vp0)
                        ast_rtp_get_peer(vp0, &vt0);
                if (tp0)
                        ast_rtp_get_peer(tp0, &tt0);
                if (pr0->get_codec)
                        codec0 = pr0->get_codec(c0);
                if ((inaddrcmp(&t1, &ac1)) ||
                    (vp1 && inaddrcmp(&vt1, &vac1)) ||
                    (tp1 && inaddrcmp(&tt1, &tac1)) ||
                    (codec1 != oldcodec1)) {
                        ast_debug(2, "Oooh, '%s' changed end address to %s:%d (format %d)\n",
                                c1->name, ast_inet_ntoa(t1.sin_addr), ntohs(t1.sin_port), codec1);
                        ast_debug(2, "Oooh, '%s' changed end vaddress to %s:%d (format %d)\n",
                                c1->name, ast_inet_ntoa(vt1.sin_addr), ntohs(vt1.sin_port), codec1);
                        ast_debug(2, "Oooh, '%s' changed end taddress to %s:%d (format %d)\n",
                                c1->name, ast_inet_ntoa(tt1.sin_addr), ntohs(tt1.sin_port), codec1);
                        ast_debug(2, "Oooh, '%s' was %s:%d/(format %d)\n",
                                c1->name, ast_inet_ntoa(ac1.sin_addr), ntohs(ac1.sin_port), oldcodec1);
                        ast_debug(2, "Oooh, '%s' was %s:%d/(format %d)\n",
                                c1->name, ast_inet_ntoa(vac1.sin_addr), ntohs(vac1.sin_port), oldcodec1);
                        ast_debug(2, "Oooh, '%s' was %s:%d/(format %d)\n",
                                c1->name, ast_inet_ntoa(tac1.sin_addr), ntohs(tac1.sin_port), oldcodec1);
                        if (pr0->set_rtp_peer(c0, t1.sin_addr.s_addr ? p1 : NULL, vt1.sin_addr.s_addr ? vp1 : NULL, tt1.sin_addr.s_addr ? tp1 : NULL, codec1, ast_test_flag(p1, FLAG_NAT_ACTIVE)))
                                ast_log(LOG_WARNING, "Channel '%s' failed to update to '%s'\n", c0->name, c1->name);
                        memcpy(&ac1, &t1, sizeof(ac1));
                        memcpy(&vac1, &vt1, sizeof(vac1));
                        memcpy(&tac1, &tt1, sizeof(tac1));
                        oldcodec1 = codec1;
                }
                if ((inaddrcmp(&t0, &ac0)) ||
                    (vp0 && inaddrcmp(&vt0, &vac0)) ||
                    (tp0 && inaddrcmp(&tt0, &tac0))) {
                        ast_debug(2, "Oooh, '%s' changed end address to %s:%d (format %d)\n",
                                c0->name, ast_inet_ntoa(t0.sin_addr), ntohs(t0.sin_port), codec0);
                        ast_debug(2, "Oooh, '%s' was %s:%d/(format %d)\n",
                                c0->name, ast_inet_ntoa(ac0.sin_addr), ntohs(ac0.sin_port), oldcodec0);
                        if (pr1->set_rtp_peer(c1, t0.sin_addr.s_addr ? p0 : NULL, vt0.sin_addr.s_addr ? vp0 : NULL, tt0.sin_addr.s_addr ? tp0 : NULL, codec0, ast_test_flag(p0, FLAG_NAT_ACTIVE)))
                                ast_log(LOG_WARNING, "Channel '%s' failed to update to '%s'\n", c1->name, c0->name);
                        memcpy(&ac0, &t0, sizeof(ac0));
                        memcpy(&vac0, &vt0, sizeof(vac0));
                        memcpy(&tac0, &tt0, sizeof(tac0));
                        oldcodec0 = codec0;
                }

                /* Wait for frame to come in on the channels */
                if (!(who = ast_waitfor_n(cs, 2, &timeoutms))) {
                        if (!timeoutms) {
                                if (pr0->set_rtp_peer(c0, NULL, NULL, NULL, 0, 0))
                                        ast_log(LOG_WARNING, "Channel '%s' failed to break RTP bridge\n", c0->name);
                                if (pr1->set_rtp_peer(c1, NULL, NULL, NULL, 0, 0))
                                        ast_log(LOG_WARNING, "Channel '%s' failed to break RTP bridge\n", c1->name);
                                return AST_BRIDGE_RETRY;
                        }
                        ast_debug(1, "Ooh, empty read...\n");
                        if (ast_check_hangup(c0) || ast_check_hangup(c1))
                                break;
                        continue;
                }
                fr = ast_read(who);
                other = (who == c0) ? c1 : c0;
                if (!fr || ((fr->frametype == AST_FRAME_DTMF) &&
                            (((who == c0) && (flags & AST_BRIDGE_DTMF_CHANNEL_0)) ||
                             ((who == c1) && (flags & AST_BRIDGE_DTMF_CHANNEL_1))))) {
                        /* Break out of bridge */
                        *fo = fr;
                        *rc = who;
                        ast_debug(1, "Oooh, got a %s\n", fr ? "digit" : "hangup");
                        if (c0->tech_pvt == pvt0)
                                if (pr0->set_rtp_peer(c0, NULL, NULL, NULL, 0, 0))
                                        ast_log(LOG_WARNING, "Channel '%s' failed to break RTP bridge\n", c0->name);
                        if (c1->tech_pvt == pvt1)
                                if (pr1->set_rtp_peer(c1, NULL, NULL, NULL, 0, 0))
                                        ast_log(LOG_WARNING, "Channel '%s' failed to break RTP bridge\n", c1->name);
                        ast_poll_channel_del(c0, c1);
                        return AST_BRIDGE_COMPLETE;
                } else if ((fr->frametype == AST_FRAME_CONTROL) && !(flags & AST_BRIDGE_IGNORE_SIGS)) {
                        if ((fr->subclass == AST_CONTROL_HOLD) ||
                            (fr->subclass == AST_CONTROL_UNHOLD) ||
                            (fr->subclass == AST_CONTROL_VIDUPDATE)) {
                                if (fr->subclass == AST_CONTROL_HOLD) {
                                        /* If we someone went on hold we want the other side to reinvite back to us */
                                        if (who == c0)
                                                pr1->set_rtp_peer(c1, NULL, NULL, NULL, 0, 0);
                                        else
                                                pr0->set_rtp_peer(c0, NULL, NULL, NULL, 0, 0);
                                } else if (fr->subclass == AST_CONTROL_UNHOLD) {
                                        /* If they went off hold they should go back to being direct */
                                        if (who == c0)
                                                pr1->set_rtp_peer(c1, p0, vp0, tp0, codec0, ast_test_flag(p0, FLAG_NAT_ACTIVE));
                                        else
                                                pr0->set_rtp_peer(c0, p1, vp1, tp1, codec1, ast_test_flag(p1, FLAG_NAT_ACTIVE));
                                }
                                /* Update local address information */
                                ast_rtp_get_peer(p0, &t0);
                                memcpy(&ac0, &t0, sizeof(ac0));
                                ast_rtp_get_peer(p1, &t1);
                                memcpy(&ac1, &t1, sizeof(ac1));
                                /* Update codec information */
                                if (pr0->get_codec)
                                        oldcodec0 = codec0 = pr0->get_codec(c0);
                                if (pr1->get_codec)
                                        oldcodec1 = codec1 = pr1->get_codec(c1);
                                ast_indicate_data(other, fr->subclass, fr->data, fr->datalen);
                                ast_frfree(fr);
                        } else {
                                *fo = fr;
                                *rc = who;
                                ast_debug(1, "Got a FRAME_CONTROL (%d) frame on channel %s\n", fr->subclass, who->name);
                                return AST_BRIDGE_COMPLETE;
                        }
                } else {
                        if ((fr->frametype == AST_FRAME_DTMF_BEGIN) ||
                            (fr->frametype == AST_FRAME_DTMF) ||
                            (fr->frametype == AST_FRAME_VOICE) ||
                            (fr->frametype == AST_FRAME_VIDEO) ||
                            (fr->frametype == AST_FRAME_IMAGE) ||
                            (fr->frametype == AST_FRAME_HTML) ||
                            (fr->frametype == AST_FRAME_MODEM) ||
                            (fr->frametype == AST_FRAME_TEXT)) {
                                ast_write(other, fr);
                        }
                        ast_frfree(fr);
                }
                /* Swap priority */
#ifndef HAVE_EPOLL
                cs[2] = cs[0];
                cs[0] = cs[1];
                cs[1] = cs[2];
#endif
        }

        ast_poll_channel_del(c0, c1);

        if (pr0->set_rtp_peer(c0, NULL, NULL, NULL, 0, 0))
                ast_log(LOG_WARNING, "Channel '%s' failed to break RTP bridge\n", c0->name);
        if (pr1->set_rtp_peer(c1, NULL, NULL, NULL, 0, 0))
                ast_log(LOG_WARNING, "Channel '%s' failed to break RTP bridge\n", c1->name);

        return AST_BRIDGE_FAILED;
}

/*! \brief P2P RTP Callback */
#ifdef P2P_INTENSE
static int p2p_rtp_callback(int *id, int fd, short events, void *cbdata)
{
        int res = 0, hdrlen = 12;
        struct sockaddr_in sin;
        socklen_t len;
        unsigned int *header;
        struct ast_rtp *rtp = cbdata, *bridged = NULL;

        if (!rtp)
                return 1;

        len = sizeof(sin);
        if ((res = recvfrom(fd, rtp->rawdata + AST_FRIENDLY_OFFSET, sizeof(rtp->rawdata) - AST_FRIENDLY_OFFSET, 0, (struct sockaddr *)&sin, &len)) < 0)
                return 1;

        header = (unsigned int *)(rtp->rawdata + AST_FRIENDLY_OFFSET);
        
        /* If NAT support is turned on, then see if we need to change their address */
        if ((rtp->nat) && 
            ((rtp->them.sin_addr.s_addr != sin.sin_addr.s_addr) ||
             (rtp->them.sin_port != sin.sin_port))) {
                rtp->them = sin;
                rtp->rxseqno = 0;
                ast_set_flag(rtp, FLAG_NAT_ACTIVE);
                if (option_debug || rtpdebug)
                        ast_debug(0, "P2P RTP NAT: Got audio from other end. Now sending to address %s:%d\n", ast_inet_ntoa(rtp->them.sin_addr), ntohs(rtp->them.sin_port));
        }

        /* Write directly out to other RTP stream if bridged */
        if ((bridged = ast_rtp_get_bridged(rtp)))
                bridge_p2p_rtp_write(rtp, bridged, header, res, hdrlen);
        
        return 1;
}

/*! \brief Helper function to switch a channel and RTP stream into callback mode */
static int p2p_callback_enable(struct ast_channel *chan, struct ast_rtp *rtp, int **iod)
{
        /* If we need DTMF, are looking for STUN, or we have no IO structure then we can't do direct callback */
        if (ast_test_flag(rtp, FLAG_P2P_NEED_DTMF) || ast_test_flag(rtp, FLAG_HAS_STUN) || !rtp->io)
                return 0;

        /* If the RTP structure is already in callback mode, remove it temporarily */
        if (rtp->ioid) {
                ast_io_remove(rtp->io, rtp->ioid);
                rtp->ioid = NULL;
        }

        /* Steal the file descriptors from the channel */
        chan->fds[0] = -1;

        /* Now, fire up callback mode */
        iod[0] = ast_io_add(rtp->io, ast_rtp_fd(rtp), p2p_rtp_callback, AST_IO_IN, rtp);

        return 1;
}
#else
static int p2p_callback_enable(struct ast_channel *chan, struct ast_rtp *rtp, int **iod)
{
        return 0;
}
#endif

/*! \brief Helper function to switch a channel and RTP stream out of callback mode */
static int p2p_callback_disable(struct ast_channel *chan, struct ast_rtp *rtp, int **iod)
{
        ast_channel_lock(chan);

        /* Remove the callback from the IO context */
        ast_io_remove(rtp->io, iod[0]);

        /* Restore file descriptors */
        chan->fds[0] = ast_rtp_fd(rtp);
        ast_channel_unlock(chan);

        /* Restore callback mode if previously used */
        if (ast_test_flag(rtp, FLAG_CALLBACK_MODE))
                rtp->ioid = ast_io_add(rtp->io, ast_rtp_fd(rtp), rtpread, AST_IO_IN, rtp);

        return 0;
}

/*! \brief Helper function that sets what an RTP structure is bridged to */
static void p2p_set_bridge(struct ast_rtp *rtp0, struct ast_rtp *rtp1)
{
        rtp_bridge_lock(rtp0);
        rtp0->bridged = rtp1;
        rtp_bridge_unlock(rtp0);

        return;
}

/*! \brief Bridge loop for partial native bridge (packet2packet) 

        In p2p mode, Asterisk is a very basic RTP proxy, just forwarding whatever
        rtp/rtcp we get in to the channel. 
        \note this currently only works for Audio
*/
static enum ast_bridge_result bridge_p2p_loop(struct ast_channel *c0, struct ast_channel *c1, struct ast_rtp *p0, struct ast_rtp *p1, int timeoutms, int flags, struct ast_frame **fo, struct ast_channel **rc, void *pvt0, void *pvt1)
{
        struct ast_frame *fr = NULL;
        struct ast_channel *who = NULL, *other = NULL, *cs[3] = {NULL, };
        int *p0_iod[2] = {NULL, NULL}, *p1_iod[2] = {NULL, NULL};
        int p0_callback = 0, p1_callback = 0;
        enum ast_bridge_result res = AST_BRIDGE_FAILED;

        /* Okay, setup each RTP structure to do P2P forwarding */
        ast_clear_flag(p0, FLAG_P2P_SENT_MARK);
        p2p_set_bridge(p0, p1);
        ast_clear_flag(p1, FLAG_P2P_SENT_MARK);
        p2p_set_bridge(p1, p0);

        /* Activate callback modes if possible */
        p0_callback = p2p_callback_enable(c0, p0, &p0_iod[0]);
        p1_callback = p2p_callback_enable(c1, p1, &p1_iod[0]);

        /* Now let go of the channel locks and be on our way */
        ast_channel_unlock(c0);
        ast_channel_unlock(c1);

        ast_poll_channel_add(c0, c1);

        /* Go into a loop forwarding frames until we don't need to anymore */
        cs[0] = c0;
        cs[1] = c1;
        cs[2] = NULL;
        for (;;) {
                /* Check if anything changed */
                if ((c0->tech_pvt != pvt0) ||
                    (c1->tech_pvt != pvt1) ||
                    (c0->masq || c0->masqr || c1->masq || c1->masqr)) {
                        ast_debug(3, "p2p-rtp-bridge: Oooh, something is weird, backing out\n");
                        /* If a masquerade needs to happen we have to try to read in a frame so that it actually happens. Without this we risk being called again and going into a loop */
                        if ((c0->masq || c0->masqr) && (fr = ast_read(c0)))
                                ast_frfree(fr);
                        if ((c1->masq || c1->masqr) && (fr = ast_read(c1)))
                                ast_frfree(fr);
                        res = AST_BRIDGE_RETRY;
                        break;
                }
                /* Wait on a channel to feed us a frame */
                if (!(who = ast_waitfor_n(cs, 2, &timeoutms))) {
                        if (!timeoutms) {
                                res = AST_BRIDGE_RETRY;
                                break;
                        }
                        if (option_debug > 2)
                                ast_log(LOG_NOTICE, "p2p-rtp-bridge: Ooh, empty read...\n");
                        if (ast_check_hangup(c0) || ast_check_hangup(c1))
                                break;
                        continue;
                }
                /* Read in frame from channel */
                fr = ast_read(who);
                other = (who == c0) ? c1 : c0;
                /* Depending on the frame we may need to break out of our bridge */
                if (!fr || ((fr->frametype == AST_FRAME_DTMF) &&
                            ((who == c0) && (flags & AST_BRIDGE_DTMF_CHANNEL_0)) |
                            ((who == c1) && (flags & AST_BRIDGE_DTMF_CHANNEL_1)))) {
                        /* Record received frame and who */
                        *fo = fr;
                        *rc = who;
                        ast_debug(3, "p2p-rtp-bridge: Ooh, got a %s\n", fr ? "digit" : "hangup");
                        res = AST_BRIDGE_COMPLETE;
                        break;
                } else if ((fr->frametype == AST_FRAME_CONTROL) && !(flags & AST_BRIDGE_IGNORE_SIGS)) {
                        if ((fr->subclass == AST_CONTROL_HOLD) ||
                            (fr->subclass == AST_CONTROL_UNHOLD) ||
                            (fr->subclass == AST_CONTROL_VIDUPDATE)) {
                                /* If we are going on hold, then break callback mode and P2P bridging */
                                if (fr->subclass == AST_CONTROL_HOLD) {
                                        if (p0_callback)
                                                p0_callback = p2p_callback_disable(c0, p0, &p0_iod[0]);
                                        if (p1_callback)
                                                p1_callback = p2p_callback_disable(c1, p1, &p1_iod[0]);
                                        p2p_set_bridge(p0, NULL);
                                        p2p_set_bridge(p1, NULL);
                                } else if (fr->subclass == AST_CONTROL_UNHOLD) {
                                        /* If we are off hold, then go back to callback mode and P2P bridging */
                               &n