From 58821db0a9dcc1a8a76e1a850a1cd8943c348bb6 Mon Sep 17 00:00:00 2001 From: winlin Date: Sat, 22 Apr 2023 11:19:01 +0800 Subject: [PATCH] WHIP: Refine code. --- .gitignore | 1 + libavformat/rtcenc.c | 111 +++++++++++++++++++++++++++---------------- 2 files changed, 71 insertions(+), 41 deletions(-) diff --git a/.gitignore b/.gitignore index 08cc4bc5e19b4..1b7086289db7f 100644 --- a/.gitignore +++ b/.gitignore @@ -42,3 +42,4 @@ /mapfile /tools/python/__pycache__/ .idea +patcheck.* diff --git a/libavformat/rtcenc.c b/libavformat/rtcenc.c index 3abc85f52a246..ec8b6579aed47 100644 --- a/libavformat/rtcenc.c +++ b/libavformat/rtcenc.c @@ -33,6 +33,8 @@ #include "url.h" #include "libavutil/random_seed.h" +#define MAX_SDP_SIZE 8192 + typedef struct RTCContext { AVClass *av_class; @@ -58,16 +60,16 @@ typedef struct RTCContext { /* The ICE username and pwd from remote server. */ char *ice_ufrag_remote; char *ice_pwd_remote; - /* The ICE candidate protocol, priority, host and port. */ + /** + * The ICE candidate protocol, priority, host and port. Note that only + * support one candidate for now. We will choose the first udp candidate. + * We will support multiple candidates in the future. + */ char *ice_protocol; - int ice_priority; char *ice_host; int ice_port; /* The SDP answer received from the WebRTC server. */ char *sdp_answer; - - /* The HTTP URL context is the transport layer for the WHIP protocol. */ - URLContext *whip_uc; } RTCContext; /** @@ -186,9 +188,15 @@ static int check_codec(AVFormatContext *s) */ static int generate_sdp_offer(AVFormatContext *s) { - int profile_iop; + int ret, profile_iop; RTCContext *rtc = s->priv_data; + char *tmp = av_mallocz(MAX_SDP_SIZE); + if (!tmp) { + av_log(s, AV_LOG_ERROR, "Failed to alloc answer: %s", s->url); + return AVERROR(EINVAL); + } + if (rtc->sdp_offer) { av_log(s, AV_LOG_ERROR, "SDP offer is already set\n"); return AVERROR(EINVAL); @@ -207,7 +215,8 @@ static int generate_sdp_offer(AVFormatContext *s) rtc->video_payload_type = 106; profile_iop = rtc->video_par->profile & FF_PROFILE_H264_CONSTRAINED ? 0xe0 : 0x00; - rtc->sdp_offer = av_asprintf( + + ret = av_strlcatf(tmp, MAX_SDP_SIZE, "v=0\r\n" "o=FFmpeg 4489045141692799359 2 IN IP4 127.0.0.1\r\n" "s=FFmpegPublishSession\r\n" @@ -262,11 +271,19 @@ static int generate_sdp_offer(AVFormatContext *s) profile_iop, rtc->video_par->level, rtc->video_ssrc, - rtc->video_ssrc - ); + rtc->video_ssrc); + if (ret >= MAX_SDP_SIZE) { + av_log(s, AV_LOG_ERROR, "Offer %d exceed max %d, %s", ret, MAX_SDP_SIZE, tmp); + ret = AVERROR(EINVAL); + goto end; + } + + rtc->sdp_offer = av_strdup(tmp); av_log(s, AV_LOG_VERBOSE, "Generated offer: %s", rtc->sdp_offer); - return 0; +end: + av_free(tmp); + return ret; } /** @@ -313,31 +330,38 @@ static int generate_sdp_offer(AVFormatContext *s) static int exchange_sdp(AVFormatContext *s) { int ret; - char headers[MAX_URL_SIZE], buf[MAX_URL_SIZE]; - char *p; + char buf[MAX_URL_SIZE]; RTCContext *rtc = s->priv_data; + /* The URL context is an HTTP transport layer for the WHIP protocol. */ + URLContext *whip_uc = NULL; + + char *tmp = av_mallocz(MAX_SDP_SIZE); + if (!tmp) { + av_log(s, AV_LOG_ERROR, "Failed to alloc answer: %s", s->url); + return AVERROR(EINVAL); + } - ret = ffurl_alloc(&rtc->whip_uc, s->url, AVIO_FLAG_READ_WRITE, &s->interrupt_callback); + ret = ffurl_alloc(&whip_uc, s->url, AVIO_FLAG_READ_WRITE, &s->interrupt_callback); if (ret < 0) { av_log(s, AV_LOG_ERROR, "Failed to alloc HTTP context: %s", s->url); - return ret; + goto end; } - snprintf(headers, sizeof(headers), + snprintf(buf, sizeof(buf), "Cache-Control: no-cache\r\n" "Content-Type: application/sdp\r\n"); - av_opt_set(rtc->whip_uc->priv_data, "headers", headers, 0); - av_opt_set(rtc->whip_uc->priv_data, "chunked_post", "0", 0); - av_opt_set_bin(rtc->whip_uc->priv_data, "post_data", rtc->sdp_offer, (int)strlen(rtc->sdp_offer), 0); + av_opt_set(whip_uc->priv_data, "headers", buf, 0); + av_opt_set(whip_uc->priv_data, "chunked_post", "0", 0); + av_opt_set_bin(whip_uc->priv_data, "post_data", rtc->sdp_offer, (int)strlen(rtc->sdp_offer), 0); - ret = ffurl_connect(rtc->whip_uc, NULL); + ret = ffurl_connect(whip_uc, NULL); if (ret < 0) { av_log(s, AV_LOG_ERROR, "Failed to request url=%s, offer: %s", s->url, rtc->sdp_offer); - return ret; + goto end; } - for (;;) { - ret = ffurl_read(rtc->whip_uc, buf, sizeof(buf)); + while (1) { + ret = ffurl_read(whip_uc, buf, sizeof(buf)); if (ret == AVERROR_EOF) { /* Reset the error because we read all response as answer util EOF. */ ret = 0; @@ -346,15 +370,23 @@ static int exchange_sdp(AVFormatContext *s) if (ret <= 0) { av_log(s, AV_LOG_ERROR, "Failed to read response from url=%s, offer is %s, answer is %s", s->url, rtc->sdp_offer, rtc->sdp_answer); - return ret; + goto end; } - p = rtc->sdp_answer; - rtc->sdp_answer = av_asprintf("%s%.*s", p ? p : "", ret, buf); - av_free(p); + ret = av_strlcatf(tmp, MAX_SDP_SIZE, "%.*s", ret, buf); + if (ret >= MAX_SDP_SIZE) { + av_log(s, AV_LOG_ERROR, "Answer %d exceed max size %d, %s", ret, MAX_SDP_SIZE, tmp); + ret = AVERROR(EINVAL); + goto end; + } } + + rtc->sdp_answer = av_strdup(tmp); av_log(s, AV_LOG_VERBOSE, "Got answer: %s", rtc->sdp_answer); +end: + ffurl_closep(&whip_uc); + av_free(tmp); return ret; } @@ -372,9 +404,7 @@ static int parse_answer(AVFormatContext *s) int i; RTCContext *rtc = s->priv_data; - pb = avio_alloc_context( - (unsigned char *)rtc->sdp_answer, (int)strlen(rtc->sdp_answer), - AVIO_FLAG_READ, NULL, NULL, NULL, NULL); + pb = avio_alloc_context(rtc->sdp_answer, strlen(rtc->sdp_answer), AVIO_FLAG_READ, NULL, NULL, NULL, NULL); if (!pb) { av_log(s, AV_LOG_ERROR, "Failed to alloc AVIOContext for answer: %s", rtc->sdp_answer); ret = AVERROR(ENOMEM); @@ -383,13 +413,11 @@ static int parse_answer(AVFormatContext *s) for (i = 0; !avio_feof(pb); i++) { ff_get_chomp_line(pb, line, sizeof(line)); - if (av_strstart(line, "a=ice-ufrag:", &ptr)) { - av_freep(&rtc->ice_ufrag_remote); + if (av_strstart(line, "a=ice-ufrag:", &ptr) && !rtc->ice_ufrag_remote) { rtc->ice_ufrag_remote = av_strdup(ptr); - } else if (av_strstart(line, "a=ice-pwd:", &ptr)) { - av_freep(&rtc->ice_pwd_remote); + } else if (av_strstart(line, "a=ice-pwd:", &ptr) && !rtc->ice_pwd_remote) { rtc->ice_pwd_remote = av_strdup(ptr); - } else if (av_strstart(line, "a=candidate:", &ptr)) { + } else if (av_strstart(line, "a=candidate:", &ptr) && !rtc->ice_protocol) { ptr = av_stristr(ptr, "udp"); if (ptr && av_stristr(ptr, "host")) { char protocol[17], host[129]; @@ -403,27 +431,29 @@ static int parse_answer(AVFormatContext *s) } if (av_strcasecmp(protocol, "udp")) { - av_log(s, AV_LOG_ERROR, "Protocol %s is not supported by RTC, choose udp", protocol); + av_log(s, AV_LOG_ERROR, "Protocol %s is not supported by RTC, choose udp, line %d %s of %s", + protocol, i, line, rtc->sdp_answer); ret = AVERROR(EINVAL); goto end; } - av_freep(&rtc->ice_protocol); rtc->ice_protocol = av_strdup(protocol); - av_freep(&rtc->ice_host); rtc->ice_host = av_strdup(host); - rtc->ice_priority = priority; rtc->ice_port = port; } } } + av_log(s, AV_LOG_VERBOSE, "SDP offer=%luB, answer=%luB, ufrag=%s, pwd=%luB, transport=%s://%s:%d\n", + strlen(rtc->sdp_offer), strlen(rtc->sdp_answer), rtc->ice_ufrag_remote, strlen(rtc->ice_pwd_remote), + rtc->ice_protocol, rtc->ice_host, rtc->ice_port); + end: avio_context_free(&pb); return ret; } -static int rtc_init(AVFormatContext *s) +static av_cold int rtc_init(AVFormatContext *s) { int ret; @@ -457,12 +487,11 @@ static int rtc_write_trailer(AVFormatContext *s) return 0; } -static void rtc_deinit(AVFormatContext *s) +static av_cold void rtc_deinit(AVFormatContext *s) { RTCContext *rtc = s->priv_data; av_freep(&rtc->sdp_offer); av_freep(&rtc->sdp_answer); - ffurl_closep(&rtc->whip_uc); av_freep(&rtc->ice_ufrag_remote); av_freep(&rtc->ice_pwd_remote); av_freep(&rtc->ice_protocol);