2 * SRTP network protocol
3 * Copyright (c) 2012 Martin Storsjo
5 * This file is part of Libav.
7 * Libav is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * Libav is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #include "libavutil/opt.h"
24 #include "avio_internal.h"
30 typedef struct SRTPProtoContext {
33 const char *out_suite, *out_params;
34 const char *in_suite, *in_params;
35 struct SRTPContext srtp_out, srtp_in;
36 uint8_t encryptbuf[1500];
39 #define D AV_OPT_FLAG_DECODING_PARAM
40 #define E AV_OPT_FLAG_ENCODING_PARAM
41 static const AVOption options[] = {
42 { "srtp_out_suite", "", offsetof(SRTPProtoContext, out_suite), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, E },
43 { "srtp_out_params", "", offsetof(SRTPProtoContext, out_params), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, E },
44 { "srtp_in_suite", "", offsetof(SRTPProtoContext, in_suite), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, E },
45 { "srtp_in_params", "", offsetof(SRTPProtoContext, in_params), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, E },
49 static const AVClass srtp_context_class = {
51 .item_name = av_default_item_name,
53 .version = LIBAVUTIL_VERSION_INT,
56 static int srtp_close(URLContext *h)
58 SRTPProtoContext *s = h->priv_data;
59 ff_srtp_free(&s->srtp_out);
60 ff_srtp_free(&s->srtp_in);
61 ffurl_close(s->rtp_hd);
66 static int srtp_open(URLContext *h, const char *uri, int flags)
68 SRTPProtoContext *s = h->priv_data;
69 char hostname[256], buf[1024], path[1024];
72 if (s->out_suite && s->out_params)
73 if ((ret = ff_srtp_set_crypto(&s->srtp_out, s->out_suite, s->out_params)) < 0)
75 if (s->in_suite && s->in_params)
76 if ((ret = ff_srtp_set_crypto(&s->srtp_in, s->in_suite, s->in_params)) < 0)
79 av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &rtp_port,
80 path, sizeof(path), uri);
81 ff_url_join(buf, sizeof(buf), "rtp", NULL, hostname, rtp_port, "%s", path);
82 if ((ret = ffurl_open(&s->rtp_hd, buf, flags, &h->interrupt_callback, NULL)) < 0)
85 h->max_packet_size = FFMIN(s->rtp_hd->max_packet_size,
86 sizeof(s->encryptbuf)) - 14;
95 static int srtp_read(URLContext *h, uint8_t *buf, int size)
97 SRTPProtoContext *s = h->priv_data;
100 ret = ffurl_read(s->rtp_hd, buf, size);
101 if (ret > 0 && s->srtp_in.aes) {
102 if (ff_srtp_decrypt(&s->srtp_in, buf, &ret) < 0)
108 static int srtp_write(URLContext *h, const uint8_t *buf, int size)
110 SRTPProtoContext *s = h->priv_data;
111 if (!s->srtp_out.aes)
112 return ffurl_write(s->rtp_hd, buf, size);
113 size = ff_srtp_encrypt(&s->srtp_out, buf, size, s->encryptbuf,
114 sizeof(s->encryptbuf));
117 return ffurl_write(s->rtp_hd, s->encryptbuf, size);
120 static int srtp_get_file_handle(URLContext *h)
122 SRTPProtoContext *s = h->priv_data;
123 return ffurl_get_file_handle(s->rtp_hd);
126 static int srtp_get_multi_file_handle(URLContext *h, int **handles,
129 SRTPProtoContext *s = h->priv_data;
130 return ffurl_get_multi_file_handle(s->rtp_hd, handles, numhandles);
133 URLProtocol ff_srtp_protocol = {
135 .url_open = srtp_open,
136 .url_read = srtp_read,
137 .url_write = srtp_write,
138 .url_close = srtp_close,
139 .url_get_file_handle = srtp_get_file_handle,
140 .url_get_multi_file_handle = srtp_get_multi_file_handle,
141 .priv_data_size = sizeof(SRTPProtoContext),
142 .priv_data_class = &srtp_context_class,
143 .flags = URL_PROTOCOL_FLAG_NETWORK,