1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/netwerk/srtp/src/include/srtp_priv.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,256 @@
1.4 +/*
1.5 + * srtp_priv.h
1.6 + *
1.7 + * private internal data structures and functions for libSRTP
1.8 + *
1.9 + * David A. McGrew
1.10 + * Cisco Systems, Inc.
1.11 + */
1.12 +/*
1.13 + *
1.14 + * Copyright (c) 2001-2006 Cisco Systems, Inc.
1.15 + * All rights reserved.
1.16 + *
1.17 + * Redistribution and use in source and binary forms, with or without
1.18 + * modification, are permitted provided that the following conditions
1.19 + * are met:
1.20 + *
1.21 + * Redistributions of source code must retain the above copyright
1.22 + * notice, this list of conditions and the following disclaimer.
1.23 + *
1.24 + * Redistributions in binary form must reproduce the above
1.25 + * copyright notice, this list of conditions and the following
1.26 + * disclaimer in the documentation and/or other materials provided
1.27 + * with the distribution.
1.28 + *
1.29 + * Neither the name of the Cisco Systems, Inc. nor the names of its
1.30 + * contributors may be used to endorse or promote products derived
1.31 + * from this software without specific prior written permission.
1.32 + *
1.33 + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1.34 + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1.35 + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
1.36 + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
1.37 + * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
1.38 + * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
1.39 + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
1.40 + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
1.41 + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
1.42 + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
1.43 + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
1.44 + * OF THE POSSIBILITY OF SUCH DAMAGE.
1.45 + *
1.46 + */
1.47 +
1.48 +#ifndef SRTP_PRIV_H
1.49 +#define SRTP_PRIV_H
1.50 +
1.51 +#include "srtp.h"
1.52 +#include "rdbx.h"
1.53 +#include "rdb.h"
1.54 +#include "integers.h"
1.55 +
1.56 +/*
1.57 + * an srtp_hdr_t represents the srtp header
1.58 + *
1.59 + * in this implementation, an srtp_hdr_t is assumed to be 32-bit aligned
1.60 + *
1.61 + * (note that this definition follows that of RFC 1889 Appendix A, but
1.62 + * is not identical)
1.63 + */
1.64 +
1.65 +#ifndef WORDS_BIGENDIAN
1.66 +
1.67 +/*
1.68 + * srtp_hdr_t represents an RTP or SRTP header. The bit-fields in
1.69 + * this structure should be declared "unsigned int" instead of
1.70 + * "unsigned char", but doing so causes the MS compiler to not
1.71 + * fully pack the bit fields.
1.72 + */
1.73 +
1.74 +typedef struct {
1.75 + unsigned char cc:4; /* CSRC count */
1.76 + unsigned char x:1; /* header extension flag */
1.77 + unsigned char p:1; /* padding flag */
1.78 + unsigned char version:2; /* protocol version */
1.79 + unsigned char pt:7; /* payload type */
1.80 + unsigned char m:1; /* marker bit */
1.81 + uint16_t seq; /* sequence number */
1.82 + uint32_t ts; /* timestamp */
1.83 + uint32_t ssrc; /* synchronization source */
1.84 +} srtp_hdr_t;
1.85 +
1.86 +#else /* BIG_ENDIAN */
1.87 +
1.88 +typedef struct {
1.89 + unsigned char version:2; /* protocol version */
1.90 + unsigned char p:1; /* padding flag */
1.91 + unsigned char x:1; /* header extension flag */
1.92 + unsigned char cc:4; /* CSRC count */
1.93 + unsigned char m:1; /* marker bit */
1.94 + unsigned pt:7; /* payload type */
1.95 + uint16_t seq; /* sequence number */
1.96 + uint32_t ts; /* timestamp */
1.97 + uint32_t ssrc; /* synchronization source */
1.98 +} srtp_hdr_t;
1.99 +
1.100 +#endif
1.101 +
1.102 +typedef struct {
1.103 + uint16_t profile_specific; /* profile-specific info */
1.104 + uint16_t length; /* number of 32-bit words in extension */
1.105 +} srtp_hdr_xtnd_t;
1.106 +
1.107 +
1.108 +/*
1.109 + * srtcp_hdr_t represents a secure rtcp header
1.110 + *
1.111 + * in this implementation, an srtcp header is assumed to be 32-bit
1.112 + * alinged
1.113 + */
1.114 +
1.115 +#ifndef WORDS_BIGENDIAN
1.116 +
1.117 +typedef struct {
1.118 + unsigned char rc:5; /* reception report count */
1.119 + unsigned char p:1; /* padding flag */
1.120 + unsigned char version:2; /* protocol version */
1.121 + unsigned char pt:8; /* payload type */
1.122 + uint16_t len; /* length */
1.123 + uint32_t ssrc; /* synchronization source */
1.124 +} srtcp_hdr_t;
1.125 +
1.126 +typedef struct {
1.127 + unsigned int index:31; /* srtcp packet index in network order! */
1.128 + unsigned int e:1; /* encrypted? 1=yes */
1.129 + /* optional mikey/etc go here */
1.130 + /* and then the variable-length auth tag */
1.131 +} srtcp_trailer_t;
1.132 +
1.133 +
1.134 +#else /* BIG_ENDIAN */
1.135 +
1.136 +typedef struct {
1.137 + unsigned char version:2; /* protocol version */
1.138 + unsigned char p:1; /* padding flag */
1.139 + unsigned char rc:5; /* reception report count */
1.140 + unsigned char pt:8; /* payload type */
1.141 + uint16_t len; /* length */
1.142 + uint32_t ssrc; /* synchronization source */
1.143 +} srtcp_hdr_t;
1.144 +
1.145 +typedef struct {
1.146 + unsigned int version:2; /* protocol version */
1.147 + unsigned int p:1; /* padding flag */
1.148 + unsigned int count:5; /* varies by packet type */
1.149 + unsigned int pt:8; /* payload type */
1.150 + uint16_t length; /* len of uint32s of packet less header */
1.151 +} rtcp_common_t;
1.152 +
1.153 +typedef struct {
1.154 + unsigned int e:1; /* encrypted? 1=yes */
1.155 + unsigned int index:31; /* srtcp packet index */
1.156 + /* optional mikey/etc go here */
1.157 + /* and then the variable-length auth tag */
1.158 +} srtcp_trailer_t;
1.159 +
1.160 +#endif
1.161 +
1.162 +
1.163 +/*
1.164 + * the following declarations are libSRTP internal functions
1.165 + */
1.166 +
1.167 +/*
1.168 + * srtp_get_stream(ssrc) returns a pointer to the stream corresponding
1.169 + * to ssrc, or NULL if no stream exists for that ssrc
1.170 + */
1.171 +
1.172 +srtp_stream_t
1.173 +srtp_get_stream(srtp_t srtp, uint32_t ssrc);
1.174 +
1.175 +
1.176 +/*
1.177 + * srtp_stream_init_keys(s, k) (re)initializes the srtp_stream_t s by
1.178 + * deriving all of the needed keys using the KDF and the key k.
1.179 + */
1.180 +
1.181 +
1.182 +err_status_t
1.183 +srtp_stream_init_keys(srtp_stream_t srtp, const void *key);
1.184 +
1.185 +/*
1.186 + * srtp_stream_init(s, p) initializes the srtp_stream_t s to
1.187 + * use the policy at the location p
1.188 + */
1.189 +err_status_t
1.190 +srtp_stream_init(srtp_stream_t srtp,
1.191 + const srtp_policy_t *p);
1.192 +
1.193 +
1.194 +/*
1.195 + * libsrtp internal datatypes
1.196 + */
1.197 +
1.198 +typedef enum direction_t {
1.199 + dir_unknown = 0,
1.200 + dir_srtp_sender = 1,
1.201 + dir_srtp_receiver = 2
1.202 +} direction_t;
1.203 +
1.204 +/*
1.205 + * an srtp_stream_t has its own SSRC, encryption key, authentication
1.206 + * key, sequence number, and replay database
1.207 + *
1.208 + * note that the keys might not actually be unique, in which case the
1.209 + * cipher_t and auth_t pointers will point to the same structures
1.210 + */
1.211 +
1.212 +typedef struct srtp_stream_ctx_t {
1.213 + uint32_t ssrc;
1.214 + cipher_t *rtp_cipher;
1.215 + auth_t *rtp_auth;
1.216 + rdbx_t rtp_rdbx;
1.217 + sec_serv_t rtp_services;
1.218 + cipher_t *rtcp_cipher;
1.219 + auth_t *rtcp_auth;
1.220 + rdb_t rtcp_rdb;
1.221 + sec_serv_t rtcp_services;
1.222 + key_limit_ctx_t *limit;
1.223 + direction_t direction;
1.224 + int allow_repeat_tx;
1.225 + ekt_stream_t ekt;
1.226 + struct srtp_stream_ctx_t *next; /* linked list of streams */
1.227 +} srtp_stream_ctx_t;
1.228 +
1.229 +
1.230 +/*
1.231 + * an srtp_ctx_t holds a stream list and a service description
1.232 + */
1.233 +
1.234 +typedef struct srtp_ctx_t {
1.235 + srtp_stream_ctx_t *stream_list; /* linked list of streams */
1.236 + srtp_stream_ctx_t *stream_template; /* act as template for other streams */
1.237 +} srtp_ctx_t;
1.238 +
1.239 +
1.240 +
1.241 +/*
1.242 + * srtp_handle_event(srtp, srtm, evnt) calls the event handling
1.243 + * function, if there is one.
1.244 + *
1.245 + * This macro is not included in the documentation as it is
1.246 + * an internal-only function.
1.247 + */
1.248 +
1.249 +#define srtp_handle_event(srtp, strm, evnt) \
1.250 + if(srtp_event_handler) { \
1.251 + srtp_event_data_t data; \
1.252 + data.session = srtp; \
1.253 + data.stream = strm; \
1.254 + data.event = evnt; \
1.255 + srtp_event_handler(&data); \
1.256 +}
1.257 +
1.258 +
1.259 +#endif /* SRTP_PRIV_H */
