Merge "stasis: Allow filtering by formatter"
[asterisk/asterisk.git] / funcs / func_base64.c
1 /*
2  * Asterisk -- An open source telephony toolkit.
3  *
4  * Copyright (C) 2005 - 2006, Digium, Inc.
5  * Copyright (C) 2005, Claude Patry
6  *
7  * See http://www.asterisk.org for more information about
8  * the Asterisk project. Please do not directly contact
9  * any of the maintainers of this project for assistance;
10  * the project provides a web site, mailing lists and IRC
11  * channels for your use.
12  *
13  * This program is free software, distributed under the terms of
14  * the GNU General Public License Version 2. See the LICENSE file
15  * at the top of the source tree.
16  */
17
18 /*! \file
19  *
20  * \brief Use the base64 as functions
21  *
22  * \ingroup functions
23  */
24
25 /*** MODULEINFO
26         <support_level>core</support_level>
27  ***/
28
29 #include "asterisk.h"
30
31 #include "asterisk/module.h"
32 #include "asterisk/pbx.h"       /* function register/unregister */
33 #include "asterisk/utils.h"
34 #include "asterisk/strings.h"
35
36 /*** DOCUMENTATION
37         <function name="BASE64_ENCODE" language="en_US">
38                 <synopsis>
39                         Encode a string in base64.
40                 </synopsis>
41                 <syntax>
42                         <parameter name="string" required="true">
43                                 <para>Input string</para>
44                         </parameter>
45                 </syntax>
46                 <description>
47                         <para>Returns the base64 string.</para>
48                 </description>
49                 <see-also>
50                         <ref type="function">BASE64_DECODE</ref>
51                         <ref type="function">AES_DECRYPT</ref>
52                         <ref type="function">AES_ENCRYPT</ref>
53                 </see-also>
54         </function>
55         <function name="BASE64_DECODE" language="en_US">
56                 <synopsis>
57                         Decode a base64 string.
58                 </synopsis>
59                 <syntax>
60                         <parameter name="string" required="true">
61                                 <para>Input string.</para>
62                         </parameter>
63                 </syntax>
64                 <description>
65                         <para>Returns the plain text string.</para>
66                 </description>
67                 <see-also>
68                         <ref type="function">BASE64_ENCODE</ref>
69                         <ref type="function">AES_DECRYPT</ref>
70                         <ref type="function">AES_ENCRYPT</ref>
71                 </see-also>
72         </function>
73  ***/
74
75 static int base64_helper(struct ast_channel *chan, const char *cmd, char *data,
76                          char *buf, struct ast_str **str, ssize_t len)
77 {
78         if (ast_strlen_zero(data)) {
79                 ast_log(LOG_WARNING, "Syntax: %s(<data>) - missing argument!\n", cmd);
80                 return -1;
81         }
82
83         if (cmd[7] == 'E') {
84                 if (buf) {
85                         ast_base64encode(buf, (unsigned char *) data, strlen(data), len);
86                 } else {
87                         if (len >= 0) {
88                                 ast_str_make_space(str, len ? len : ast_str_strlen(*str) + strlen(data) * 4 / 3 + 2);
89                         }
90                         ast_base64encode(ast_str_buffer(*str) + ast_str_strlen(*str), (unsigned char *) data, strlen(data), ast_str_size(*str) - ast_str_strlen(*str));
91                         ast_str_update(*str);
92                 }
93         } else {
94                 int decoded_len;
95                 if (buf) {
96                         decoded_len = ast_base64decode((unsigned char *) buf, data, len);
97                         /* add a terminating null at the end of buf, or at the
98                          * end of our decoded string, which ever is less */
99                         buf[decoded_len <= (len - 1) ? decoded_len : len - 1] = '\0';
100                 } else {
101                         if (len >= 0) {
102                                 ast_str_make_space(str, len ? len : ast_str_strlen(*str) + strlen(data) * 3 / 4 + 2);
103                         }
104                         decoded_len = ast_base64decode((unsigned char *) ast_str_buffer(*str) + ast_str_strlen(*str), data, ast_str_size(*str) - ast_str_strlen(*str));
105                         if (len)
106                                 /* add a terminating null at the end of our
107                                  * buffer, or at the end of our decoded string,
108                                  * which ever is less */
109                                 ast_str_buffer(*str)[decoded_len <= (len - 1) ? decoded_len : len - 1] = '\0';
110                         else
111                                 /* space for the null is allocated above */
112                                 ast_str_buffer(*str)[decoded_len] = '\0';
113
114                         ast_str_update(*str);
115                 }
116         }
117
118         return 0;
119 }
120
121 static int base64_buf_helper(struct ast_channel *chan, const char *cmd, char *data,
122                          char *buf, size_t len)
123 {
124         return base64_helper(chan, cmd, data, buf, NULL, len);
125 }
126
127 static int base64_str_helper(struct ast_channel *chan, const char *cmd, char *data,
128                          struct ast_str **buf, ssize_t len)
129 {
130         return base64_helper(chan, cmd, data, NULL, buf, len);
131 }
132
133 static struct ast_custom_function base64_encode_function = {
134         .name = "BASE64_ENCODE",
135         .read = base64_buf_helper,
136         .read2 = base64_str_helper,
137 };
138
139 static struct ast_custom_function base64_decode_function = {
140         .name = "BASE64_DECODE",
141         .read = base64_buf_helper,
142         .read2 = base64_str_helper,
143 };
144
145 static int unload_module(void)
146 {
147         return ast_custom_function_unregister(&base64_encode_function) |
148                 ast_custom_function_unregister(&base64_decode_function);
149 }
150
151 static int load_module(void)
152 {
153         return ast_custom_function_register(&base64_encode_function) |
154                 ast_custom_function_register(&base64_decode_function);
155 }
156
157 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "base64 encode/decode dialplan functions");