blob: 772c3c38db0957dcb699db39f2175641638b6bd5 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 2006 - 2007, Mikael Magnusson
*
* Mikael Magnusson <mikma@users.sourceforge.net>
*
* 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 sdp_srtp.h
*
* \brief SRTP and SDP Security descriptions
*
* Specified in RFC 4568
* Specified in RFC 3711
*
* \author Mikael Magnusson <mikma@users.sourceforge.net>
*/
#ifndef _SDP_SRTP_H
#define _SDP_SRTP_H
#include <asterisk/rtp_engine.h>
struct ast_sdp_crypto;
/*! \brief structure for secure RTP audio */
struct ast_sdp_srtp {
unsigned int flags;
struct ast_sdp_crypto *crypto;
};
/* SRTP flags */
#define AST_SRTP_CRYPTO_OFFER_OK (1 << 1)
#define AST_SRTP_CRYPTO_TAG_32 (1 << 2)
#define AST_SRTP_CRYPTO_TAG_80 (1 << 3)
/*!
* \brief allocate a ast_sdp_srtp structure
* \retval a new malloc'd ast_sdp_srtp structure on success
* \retval NULL on failure
*/
struct ast_sdp_srtp *ast_sdp_srtp_alloc(void);
/*!
* \brief free a ast_sdp_srtp structure
* \param srtp a ast_sdp_srtp structure
*/
void ast_sdp_srtp_destroy(struct ast_sdp_srtp *srtp);
/*! \brief Initialize an return an ast_sdp_crypto struct
*
* \details
* This function allocates a new ast_sdp_crypto struct and initializes its values
*
* \retval NULL on failure
* \retval a pointer to a new ast_sdp_crypto structure
*/
struct ast_sdp_crypto *ast_sdp_crypto_alloc(void);
/*! \brief Destroy a previously allocated ast_sdp_crypto struct */
void ast_sdp_crypto_destroy(struct ast_sdp_crypto *crypto);
/*! \brief Parse the a=crypto line from SDP and set appropriate values on the
* ast_sdp_crypto struct.
*
* The attribute line should already have "a=crypto:" removed.
*
* \param p A valid ast_sdp_crypto struct
* \param attr the a:crypto line from SDP
* \param rtp The rtp instance associated with the SDP being parsed
* \param srtp SRTP structure
*
* \retval 0 success
* \retval nonzero failure
*/
int ast_sdp_crypto_process(struct ast_rtp_instance *rtp, struct ast_sdp_srtp *srtp, const char *attr);
/*! \brief Generate an SRTP a=crypto offer
*
* \details
* The offer is stored on the ast_sdp_crypto struct in a_crypto
*
* \param p A valid ast_sdp_crypto struct
* \param taglen Length
*
* \retval 0 success
* \retval nonzero failure
*/
int ast_sdp_crypto_build_offer(struct ast_sdp_crypto *p, int taglen);
/*! \brief Get the crypto attribute line for the srtp structure
*
* The attribute line does not contain the initial "a=crypto:" and does
* not terminate with "\r\n".
*
* \param srtp The ast_sdp_srtp structure for which to get an attribute line
* \param dtls_enabled Whether this connection is encrypted with datagram TLS
* \param default_taglen_32 Whether to default to a tag length of 32 instead of 80
*
* \retval An attribute line containing cryptographic information
* \retval NULL if the srtp structure does not require an attribute line containing crypto information
*/
const char *ast_sdp_srtp_get_attrib(struct ast_sdp_srtp *srtp, int dtls_enabled, int default_taglen_32);
/*! \brief Get the RTP profile in use by a media session
*
* \param sdes_active Whether the media session is using SDES-SRTP
* \param instance The RTP instance associated with this media session
* \param using_avpf Whether the media session is using early feedback (AVPF)
* \param force_avp Force SAVP or SAVPF profile when DTLS is in use
*
* \retval A non-allocated string describing the profile in use (does not need to be freed)
*/
char *ast_sdp_get_rtp_profile(unsigned int sdes_active, struct ast_rtp_instance *instance, unsigned int using_avpf,
unsigned int force_avp);
#endif /* _SDP_CRYPTO_H */
|
