diff options
Diffstat (limited to 'src/modules/rtp/sap.c')
| -rw-r--r-- | src/modules/rtp/sap.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/src/modules/rtp/sap.c b/src/modules/rtp/sap.c new file mode 100644 index 0000000..7fb1a38 --- /dev/null +++ b/src/modules/rtp/sap.c @@ -0,0 +1,235 @@ +/*** + This file is part of PulseAudio. + + Copyright 2006 Lennart Poettering + + PulseAudio 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. + + PulseAudio 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 + General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with PulseAudio; if not, see <http://www.gnu.org/licenses/>. +***/ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include <stdlib.h> +#include <sys/types.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <errno.h> +#include <string.h> +#include <unistd.h> +#include <sys/ioctl.h> + +#ifdef HAVE_SYS_FILIO_H +#include <sys/filio.h> +#endif + +#ifdef HAVE_SYS_UIO_H +#include <sys/uio.h> +#endif + +#include <pulse/xmalloc.h> + +#include <pulsecore/core-error.h> +#include <pulsecore/core-util.h> +#include <pulsecore/log.h> +#include <pulsecore/macro.h> +#include <pulsecore/arpa-inet.h> + +#include "sap.h" +#include "sdp.h" + +#define MIME_TYPE "application/sdp" + +pa_sap_context* pa_sap_context_init_send(pa_sap_context *c, int fd, char *sdp_data) { + pa_assert(c); + pa_assert(fd >= 0); + pa_assert(sdp_data); + + c->fd = fd; + c->sdp_data = sdp_data; + c->msg_id_hash = (uint16_t) (rand()*rand()); + + return c; +} + +void pa_sap_context_destroy(pa_sap_context *c) { + pa_assert(c); + + pa_close(c->fd); + pa_xfree(c->sdp_data); +} + +int pa_sap_send(pa_sap_context *c, bool goodbye) { + uint32_t header; + struct sockaddr_storage sa_buf; + struct sockaddr *sa = (struct sockaddr*) &sa_buf; + socklen_t salen = sizeof(sa_buf); + struct iovec iov[4]; + struct msghdr m; + ssize_t k; + + if (getsockname(c->fd, sa, &salen) < 0) { + pa_log("getsockname() failed: %s\n", pa_cstrerror(errno)); + return -1; + } + +#ifdef HAVE_IPV6 + pa_assert(sa->sa_family == AF_INET || sa->sa_family == AF_INET6); +#else + pa_assert(sa->sa_family == AF_INET); +#endif + + header = htonl(((uint32_t) 1 << 29) | +#ifdef HAVE_IPV6 + (sa->sa_family == AF_INET6 ? (uint32_t) 1 << 28 : 0) | +#endif + (goodbye ? (uint32_t) 1 << 26 : 0) | + (c->msg_id_hash)); + + iov[0].iov_base = &header; + iov[0].iov_len = sizeof(header); + + if (sa->sa_family == AF_INET) { + iov[1].iov_base = (void*) &((struct sockaddr_in*) sa)->sin_addr; + iov[1].iov_len = 4U; +#ifdef HAVE_IPV6 + } else { + iov[1].iov_base = (void*) &((struct sockaddr_in6*) sa)->sin6_addr; + iov[1].iov_len = 16U; +#endif + } + + iov[2].iov_base = (char*) MIME_TYPE; + iov[2].iov_len = sizeof(MIME_TYPE); + + iov[3].iov_base = c->sdp_data; + iov[3].iov_len = strlen(c->sdp_data); + + m.msg_name = NULL; + m.msg_namelen = 0; + m.msg_iov = iov; + m.msg_iovlen = 4; + m.msg_control = NULL; + m.msg_controllen = 0; + m.msg_flags = 0; + + if ((k = sendmsg(c->fd, &m, MSG_DONTWAIT)) < 0) + pa_log_warn("sendmsg() failed: %s\n", pa_cstrerror(errno)); + + return (int) k; +} + +pa_sap_context* pa_sap_context_init_recv(pa_sap_context *c, int fd) { + pa_assert(c); + pa_assert(fd >= 0); + + c->fd = fd; + c->sdp_data = NULL; + return c; +} + +int pa_sap_recv(pa_sap_context *c, bool *goodbye) { + struct msghdr m; + struct iovec iov; + int size; + char *buf = NULL, *e; + uint32_t header; + unsigned six, ac, k; + ssize_t r; + + pa_assert(c); + pa_assert(goodbye); + + if (ioctl(c->fd, FIONREAD, &size) < 0) { + pa_log_warn("FIONREAD failed: %s", pa_cstrerror(errno)); + goto fail; + } + + buf = pa_xnew(char, (unsigned) size+1); + buf[size] = 0; + + iov.iov_base = buf; + iov.iov_len = (size_t) size; + + m.msg_name = NULL; + m.msg_namelen = 0; + m.msg_iov = &iov; + m.msg_iovlen = 1; + m.msg_control = NULL; + m.msg_controllen = 0; + m.msg_flags = 0; + + if ((r = recvmsg(c->fd, &m, 0)) != size) { + pa_log_warn("recvmsg() failed: %s", r < 0 ? pa_cstrerror(errno) : "size mismatch"); + goto fail; + } + + if (size < 4) { + pa_log_warn("SAP packet too short."); + goto fail; + } + + memcpy(&header, buf, sizeof(uint32_t)); + header = ntohl(header); + + if (header >> 29 != 1) { + pa_log_warn("Unsupported SAP version."); + goto fail; + } + + if ((header >> 25) & 1) { + pa_log_warn("Encrypted SAP not supported."); + goto fail; + } + + if ((header >> 24) & 1) { + pa_log_warn("Compressed SAP not supported."); + goto fail; + } + + six = (header >> 28) & 1U; + ac = (header >> 16) & 0xFFU; + + k = 4 + (six ? 16U : 4U) + ac*4U; + if ((unsigned) size < k) { + pa_log_warn("SAP packet too short (AD)."); + goto fail; + } + + e = buf + k; + size -= (int) k; + + if ((unsigned) size >= sizeof(MIME_TYPE) && pa_streq(e, MIME_TYPE)) { + e += sizeof(MIME_TYPE); + size -= (int) sizeof(MIME_TYPE); + } else if ((unsigned) size < sizeof(PA_SDP_HEADER)-1 || strncmp(e, PA_SDP_HEADER, sizeof(PA_SDP_HEADER)-1)) { + pa_log_warn("Invalid SDP header."); + goto fail; + } + + if (c->sdp_data) + pa_xfree(c->sdp_data); + + c->sdp_data = pa_xstrndup(e, (unsigned) size); + pa_xfree(buf); + + *goodbye = !!((header >> 26) & 1); + + return 0; + +fail: + pa_xfree(buf); + + return -1; +} |