--- /dev/null
+/*
+ * SCTP protocol
+ * Copyright (c) 2012 Luca Barbato
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ *
+ * sctp url_protocol
+ *
+ * url syntax: sctp://host:port[?option=val...]
+ * option: 'listen' : listen for an incoming connection
+ * 'max_streams=n' : set the maximum number of streams
+ * 'reuse=1' : enable reusing the socket [TBD]
+ *
+ * by setting the maximum number of streams the protocol will use the
+ * first two bytes of the incoming/outgoing buffer to store the
+ * stream number of the packet being read/written.
+ * @see sctp_read
+ * @see sctp_write
+ */
+
+
+#include <netinet/in.h>
+#include <netinet/sctp.h>
+#include <sys/time.h>
+#include <unistd.h>
+
+#include "config.h"
+
+#if HAVE_POLL_H
+#include <poll.h>
+#endif
+
+#include "libavutil/intreadwrite.h"
+#include "libavutil/parseutils.h"
+#include "avformat.h"
+#include "internal.h"
+#include "network.h"
+#include "os_support.h"
+#include "url.h"
+
+/*
+ * The sctp_recvmsg and sctp_sendmsg functions are part of the user
+ * library that offers support
+ * for the SCTP kernel Implementation. The main purpose of this
+ * code is to provide the SCTP Socket API mappings for user
+ * application to interface with the SCTP in kernel.
+ *
+ * This implementation is based on the Socket API Extensions for SCTP
+ * defined in <draft-ietf-tsvwg-sctpsocket-10.txt>
+ *
+ * Copyright (c) 2003 International Business Machines, Corp.
+ *
+ * Written or modified by:
+ * Ryan Layer <rmlayer@us.ibm.com>
+ */
+
+static int ff_sctp_recvmsg(int s, void *msg, size_t len, struct sockaddr *from,
+ socklen_t *fromlen, struct sctp_sndrcvinfo *sinfo,
+ int *msg_flags)
+{
+ int recvb;
+ struct iovec iov;
+ char incmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))];
+ struct msghdr inmsg = { 0 };
+ struct cmsghdr *cmsg = NULL;
+
+ iov.iov_base = msg;
+ iov.iov_len = len;
+
+ inmsg.msg_name = from;
+ inmsg.msg_namelen = fromlen ? *fromlen : 0;
+ inmsg.msg_iov = &iov;
+ inmsg.msg_iovlen = 1;
+ inmsg.msg_control = incmsg;
+ inmsg.msg_controllen = sizeof(incmsg);
+
+ if ((recvb = recvmsg(s, &inmsg, msg_flags ? *msg_flags : 0)) < 0)
+ return recvb;
+
+ if (fromlen)
+ *fromlen = inmsg.msg_namelen;
+ if (msg_flags)
+ *msg_flags = inmsg.msg_flags;
+
+ for (cmsg = CMSG_FIRSTHDR(&inmsg); cmsg != NULL;
+ cmsg = CMSG_NXTHDR(&inmsg, cmsg)) {
+ if ((IPPROTO_SCTP == cmsg->cmsg_level) &&
+ (SCTP_SNDRCV == cmsg->cmsg_type))
+ break;
+ }
+
+ /* Copy sinfo. */
+ if (cmsg)
+ memcpy(sinfo, CMSG_DATA(cmsg), sizeof(struct sctp_sndrcvinfo));
+
+ return recvb;
+}
+
+static int ff_sctp_send(int s, const void *msg, size_t len,
+ const struct sctp_sndrcvinfo *sinfo, int flags)
+{
+ struct msghdr outmsg;
+ struct iovec iov;
+
+ outmsg.msg_name = NULL;
+ outmsg.msg_namelen = 0;
+ outmsg.msg_iov = &iov;
+ iov.iov_base = msg;
+ iov.iov_len = len;
+ outmsg.msg_iovlen = 1;
+ outmsg.msg_controllen = 0;
+
+ if (sinfo) {
+ char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))];
+ struct cmsghdr *cmsg;
+
+ outmsg.msg_control = outcmsg;
+ outmsg.msg_controllen = sizeof(outcmsg);
+ outmsg.msg_flags = 0;
+
+ cmsg = CMSG_FIRSTHDR(&outmsg);
+ cmsg->cmsg_level = IPPROTO_SCTP;
+ cmsg->cmsg_type = SCTP_SNDRCV;
+ cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo));
+
+ outmsg.msg_controllen = cmsg->cmsg_len;
+ memcpy(CMSG_DATA(cmsg), sinfo, sizeof(struct sctp_sndrcvinfo));
+ }
+
+ return sendmsg(s, &outmsg, flags);
+}
+
+typedef struct SCTPContext {
+ int fd;
+ int max_streams;
+ struct sockaddr_storage dest_addr;
+ socklen_t dest_addr_len;
+} SCTPContext;
+
+static int sctp_open(URLContext *h, const char *uri, int flags)
+{
+ struct addrinfo *ai, *cur_ai;
+ struct addrinfo hints = { 0 };
+ struct sctp_event_subscribe event = { 0 };
+ struct sctp_initmsg initparams = { 0 };
+ int port;
+ int fd = -1;
+ SCTPContext *s = h->priv_data;
+ const char *p;
+ char buf[256];
+ int ret, listen_socket = 0;
+ char hostname[1024], proto[1024], path[1024];
+ char portstr[10];
+
+ av_url_split(proto, sizeof(proto), NULL, 0, hostname, sizeof(hostname),
+ &port, path, sizeof(path), uri);
+ if (strcmp(proto,"sctp") || port <= 0 || port >= 65536)
+ return AVERROR(EINVAL);
+
+ s->max_streams = 0;
+ p = strchr(uri, '?');
+ if (p) {
+ if (av_find_info_tag(buf, sizeof(buf), "listen", p))
+ listen_socket = 1;
+ if (av_find_info_tag(buf, sizeof(buf), "max_streams", p))
+ s->max_streams = strtol(buf, NULL, 10);
+ }
+
+ hints.ai_family = AF_UNSPEC;
+ hints.ai_socktype = SOCK_STREAM;
+ snprintf(portstr, sizeof(portstr), "%d", port);
+ ret = getaddrinfo(hostname, portstr, &hints, &ai);
+ if (ret) {
+ av_log(h, AV_LOG_ERROR, "Failed to resolve hostname %s: %s\n",
+ hostname, gai_strerror(ret));
+ return AVERROR(EIO);
+ }
+
+ cur_ai = ai;
+
+ fd = socket(cur_ai->ai_family, SOCK_STREAM, IPPROTO_SCTP);
+ if (fd < 0)
+ goto fail;
+
+ s->dest_addr_len = sizeof(s->dest_addr);
+
+ if (listen_socket) {
+ int fd1;
+ ret = bind(fd, cur_ai->ai_addr, cur_ai->ai_addrlen);
+ listen(fd, 100);
+ fd1 = accept(fd, NULL, NULL);
+ closesocket(fd);
+ fd = fd1;
+ } else
+ ret = connect(fd, cur_ai->ai_addr, cur_ai->ai_addrlen);
+
+ ff_socket_nonblock(fd, 1);
+
+ event.sctp_data_io_event = 1;
+ /* TODO: Subscribe to more event types and handle them */
+
+ if (setsockopt(fd, IPPROTO_SCTP, SCTP_EVENTS, &event,
+ sizeof(event)) != 0) {
+ av_log(h, AV_LOG_ERROR,
+ "SCTP ERROR: Unable to subscribe to events\n");
+ goto fail;
+ }
+
+ if (s->max_streams) {
+ initparams.sinit_max_instreams = s->max_streams;
+ initparams.sinit_num_ostreams = s->max_streams;
+ if (setsockopt(fd, SOL_SCTP, SCTP_INITMSG, &initparams,
+ sizeof(initparams)) < 0)
+ av_log(h, AV_LOG_ERROR,
+ "SCTP ERROR: Unable to initialize socket max streams %d\n",
+ s->max_streams);
+ }
+
+ h->priv_data = s;
+ h->is_streamed = 1;
+ s->fd = fd;
+ freeaddrinfo(ai);
+ return 0;
+
+fail:
+ ret = AVERROR(EIO);
+ freeaddrinfo(ai);
+ return ret;
+}
+
+static int sctp_wait_fd(int fd, int write)
+{
+ int ev = write ? POLLOUT : POLLIN;
+ struct pollfd p = { .fd = fd, .events = ev, .revents = 0 };
+ int ret;
+
+ ret = poll(&p, 1, 100);
+ return ret < 0 ? ff_neterrno() : p.revents & ev ? 0 : AVERROR(EAGAIN);
+}
+
+static int sctp_read(URLContext *h, uint8_t *buf, int size)
+{
+ SCTPContext *s = h->priv_data;
+ int ret;
+
+ if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
+ ret = sctp_wait_fd(s->fd, 0);
+ if (ret < 0)
+ return ret;
+ }
+
+ if (s->max_streams) {
+ /*StreamId is introduced as a 2byte code into the stream*/
+ struct sctp_sndrcvinfo info = { 0 };
+ ret = ff_sctp_recvmsg(s->fd, buf + 2, size - 2, NULL, 0, &info, 0);
+ AV_WB16(buf, info.sinfo_stream);
+ ret = ret < 0 ? ret : ret + 2;
+ } else
+ ret = recv(s->fd, buf, size, 0);
+
+ return ret < 0 ? ff_neterrno() : ret;
+}
+
+static int sctp_write(URLContext *h, const uint8_t *buf, int size)
+{
+ SCTPContext *s = h->priv_data;
+ int ret;
+
+ if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
+ ret = sctp_wait_fd(s->fd, 1);
+ if (ret < 0)
+ return ret;
+ }
+
+ if (s->max_streams) {
+ /*StreamId is introduced as a 2byte code into the stream*/
+ struct sctp_sndrcvinfo info = { 0 };
+ info.sinfo_stream = AV_RB16(buf);
+ if (info.sinfo_stream > s->max_streams)
+ abort();
+ ret = ff_sctp_send(s->fd, buf + 2, size - 2, &info, MSG_EOR);
+ } else
+ ret = send(s->fd, buf, size, 0);
+
+ return ret < 0 ? ff_neterrno() : ret;
+}
+
+static int sctp_close(URLContext *h)
+{
+ SCTPContext *s = h->priv_data;
+ closesocket(s->fd);
+ return 0;
+}
+
+static int sctp_get_file_handle(URLContext *h)
+{
+ SCTPContext *s = h->priv_data;
+ return s->fd;
+}
+
+URLProtocol ff_sctp_protocol = {
+ .name = "sctp",
+ .url_open = sctp_open,
+ .url_read = sctp_read,
+ .url_write = sctp_write,
+ .url_close = sctp_close,
+ .url_get_file_handle = sctp_get_file_handle,
+ .priv_data_size = sizeof(SCTPContext),
+ .flags = URL_PROTOCOL_FLAG_NETWORK,
+};