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Diffstat (limited to 'netwerk/srtp/src/include/srtp_priv.h')
| -rw-r--r-- | netwerk/srtp/src/include/srtp_priv.h | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/netwerk/srtp/src/include/srtp_priv.h b/netwerk/srtp/src/include/srtp_priv.h new file mode 100644 index 000000000..cf2274eb6 --- /dev/null +++ b/netwerk/srtp/src/include/srtp_priv.h @@ -0,0 +1,256 @@ +/* + * srtp_priv.h + * + * private internal data structures and functions for libSRTP + * + * David A. McGrew + * Cisco Systems, Inc. + */ +/* + * + * Copyright (c) 2001-2006 Cisco Systems, Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials provided + * with the distribution. + * + * Neither the name of the Cisco Systems, Inc. nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, + * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED + * OF THE POSSIBILITY OF SUCH DAMAGE. + * + */ + +#ifndef SRTP_PRIV_H +#define SRTP_PRIV_H + +#include "srtp.h" +#include "rdbx.h" +#include "rdb.h" +#include "integers.h" + +/* + * an srtp_hdr_t represents the srtp header + * + * in this implementation, an srtp_hdr_t is assumed to be 32-bit aligned + * + * (note that this definition follows that of RFC 1889 Appendix A, but + * is not identical) + */ + +#ifndef WORDS_BIGENDIAN + +/* + * srtp_hdr_t represents an RTP or SRTP header. The bit-fields in + * this structure should be declared "unsigned int" instead of + * "unsigned char", but doing so causes the MS compiler to not + * fully pack the bit fields. + */ + +typedef struct { + unsigned char cc:4; /* CSRC count */ + unsigned char x:1; /* header extension flag */ + unsigned char p:1; /* padding flag */ + unsigned char version:2; /* protocol version */ + unsigned char pt:7; /* payload type */ + unsigned char m:1; /* marker bit */ + uint16_t seq; /* sequence number */ + uint32_t ts; /* timestamp */ + uint32_t ssrc; /* synchronization source */ +} srtp_hdr_t; + +#else /* BIG_ENDIAN */ + +typedef struct { + unsigned char version:2; /* protocol version */ + unsigned char p:1; /* padding flag */ + unsigned char x:1; /* header extension flag */ + unsigned char cc:4; /* CSRC count */ + unsigned char m:1; /* marker bit */ + unsigned pt:7; /* payload type */ + uint16_t seq; /* sequence number */ + uint32_t ts; /* timestamp */ + uint32_t ssrc; /* synchronization source */ +} srtp_hdr_t; + +#endif + +typedef struct { + uint16_t profile_specific; /* profile-specific info */ + uint16_t length; /* number of 32-bit words in extension */ +} srtp_hdr_xtnd_t; + + +/* + * srtcp_hdr_t represents a secure rtcp header + * + * in this implementation, an srtcp header is assumed to be 32-bit + * alinged + */ + +#ifndef WORDS_BIGENDIAN + +typedef struct { + unsigned char rc:5; /* reception report count */ + unsigned char p:1; /* padding flag */ + unsigned char version:2; /* protocol version */ + unsigned char pt:8; /* payload type */ + uint16_t len; /* length */ + uint32_t ssrc; /* synchronization source */ +} srtcp_hdr_t; + +typedef struct { + unsigned int index:31; /* srtcp packet index in network order! */ + unsigned int e:1; /* encrypted? 1=yes */ + /* optional mikey/etc go here */ + /* and then the variable-length auth tag */ +} srtcp_trailer_t; + + +#else /* BIG_ENDIAN */ + +typedef struct { + unsigned char version:2; /* protocol version */ + unsigned char p:1; /* padding flag */ + unsigned char rc:5; /* reception report count */ + unsigned char pt:8; /* payload type */ + uint16_t len; /* length */ + uint32_t ssrc; /* synchronization source */ +} srtcp_hdr_t; + +typedef struct { + unsigned int version:2; /* protocol version */ + unsigned int p:1; /* padding flag */ + unsigned int count:5; /* varies by packet type */ + unsigned int pt:8; /* payload type */ + uint16_t length; /* len of uint32s of packet less header */ +} rtcp_common_t; + +typedef struct { + unsigned int e:1; /* encrypted? 1=yes */ + unsigned int index:31; /* srtcp packet index */ + /* optional mikey/etc go here */ + /* and then the variable-length auth tag */ +} srtcp_trailer_t; + +#endif + + +/* + * the following declarations are libSRTP internal functions + */ + +/* + * srtp_get_stream(ssrc) returns a pointer to the stream corresponding + * to ssrc, or NULL if no stream exists for that ssrc + */ + +srtp_stream_t +srtp_get_stream(srtp_t srtp, uint32_t ssrc); + + +/* + * srtp_stream_init_keys(s, k) (re)initializes the srtp_stream_t s by + * deriving all of the needed keys using the KDF and the key k. + */ + + +err_status_t +srtp_stream_init_keys(srtp_stream_t srtp, const void *key); + +/* + * srtp_stream_init(s, p) initializes the srtp_stream_t s to + * use the policy at the location p + */ +err_status_t +srtp_stream_init(srtp_stream_t srtp, + const srtp_policy_t *p); + + +/* + * libsrtp internal datatypes + */ + +typedef enum direction_t { + dir_unknown = 0, + dir_srtp_sender = 1, + dir_srtp_receiver = 2 +} direction_t; + +/* + * an srtp_stream_t has its own SSRC, encryption key, authentication + * key, sequence number, and replay database + * + * note that the keys might not actually be unique, in which case the + * cipher_t and auth_t pointers will point to the same structures + */ + +typedef struct srtp_stream_ctx_t { + uint32_t ssrc; + cipher_t *rtp_cipher; + auth_t *rtp_auth; + rdbx_t rtp_rdbx; + sec_serv_t rtp_services; + cipher_t *rtcp_cipher; + auth_t *rtcp_auth; + rdb_t rtcp_rdb; + sec_serv_t rtcp_services; + key_limit_ctx_t *limit; + direction_t direction; + int allow_repeat_tx; + ekt_stream_t ekt; + struct srtp_stream_ctx_t *next; /* linked list of streams */ +} srtp_stream_ctx_t; + + +/* + * an srtp_ctx_t holds a stream list and a service description + */ + +typedef struct srtp_ctx_t { + srtp_stream_ctx_t *stream_list; /* linked list of streams */ + srtp_stream_ctx_t *stream_template; /* act as template for other streams */ +} srtp_ctx_t; + + + +/* + * srtp_handle_event(srtp, srtm, evnt) calls the event handling + * function, if there is one. + * + * This macro is not included in the documentation as it is + * an internal-only function. + */ + +#define srtp_handle_event(srtp, strm, evnt) \ + if(srtp_event_handler) { \ + srtp_event_data_t data; \ + data.session = srtp; \ + data.stream = strm; \ + data.event = evnt; \ + srtp_event_handler(&data); \ +} + + +#endif /* SRTP_PRIV_H */ |