#~~~~~~~~~~~~~~~~~
"set time to live value"
int typestr="num"
-default="10"
+default="-1"
optional
details="
- This option instructs the udp sender to set the time to live to
- \"num\" for the sending udp socket. Only useful for multicast
- udp streaming.
+ This option applies exclusively to multicast UDPv4/v6 streaming.
+
+ For the sending UDPv4 socket it sets the multicast Time-To-Live
+ value to \"num\". Traditional TTL scope values are: 0=host,
+ 1=network, 32=same site, 64=same region, 128=same continent,
+ 255=unrestricted. Please note however that this scoping is not
+ a good solution: RFC 2365 e.g. presents a better alternative.
+
+ When using UDPv6 multicasting, the option sets the number of
+ multicast hops (as described in RFC 3493); a value of -1
+ allows the kernel to auto-select the hop value.
"
</qu>
free(buf);
return ret;
}
-
-static int resolve(const char *hostname, unsigned short port,
- struct sockaddr_in *addr)
-{
- struct hostent *host;
-
- assert(hostname);
- host = gethostbyname(hostname);
- if (!host)
- return -ERRNO_TO_PARA_ERROR(h_errno);
- if (addr) {
- memcpy(&addr->sin_addr, host->h_addr_list[0], host->h_length);
- addr->sin_port = port;
- }
- return 1;
-}
-
-/*
- * Create an UDP socket.
- *
- * If the given address is a multicast adress, the socket will be set
- * to use the multicast TTL ttl and sets the datagrams to loop back.
- *
- * \return The fd of the socket on success, negative on errors.
- */
-static int create_udp_socket(struct sockaddr_in *addr,
- unsigned short port, unsigned char ttl)
-{
- int ret, fd, yes = 1;
-
- assert(addr);
- ret = socket(PF_INET, SOCK_DGRAM, 0);
- if (ret < 0)
- return -ERRNO_TO_PARA_ERROR(errno);
- fd = ret;
- /* reuse addresses */
- ret = setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes));
- if (ret < 0) {
- ret = -ERRNO_TO_PARA_ERROR(errno);
- goto err;
- }
- addr->sin_family = AF_INET;
- addr->sin_port = htons(port);
- /* set the TTL and turn on multicast loop */
- if (IN_MULTICAST(htonl(addr->sin_addr.s_addr))) {
- unsigned char loop = 1;
- ret = setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl,
- sizeof(ttl));
- if (ret < 0) {
- ret = -ERRNO_TO_PARA_ERROR(errno);
- goto err;
- }
- ret = setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP, &loop,
- sizeof(loop));
- if (ret < 0) {
- ret = -ERRNO_TO_PARA_ERROR(errno);
- goto err;
- }
- }
- return fd;
-err:
- close(fd);
- return ret;
-}
-
-/**
- * Create and connect a sending UDP socket.
- *
- * \param hostname Where to send to (name or IPv4 address).
- * \param port The udp port to use.
- * \param ttl Time to live (only relevant for multicast).
- *
- * \return The fd of the socket on success, negative on error.
- */
-int create_udp_send_socket(char *hostname, unsigned short port,
- unsigned char ttl)
-{
- struct sockaddr_in addr;
- int fd, ret = resolve(hostname, port, &addr);
-
- if (ret < 0)
- return ret;
- ret = create_udp_socket(&addr, port, ttl);
- if (ret < 0)
- return ret;
- fd = ret;
- ret = connect(fd, (struct sockaddr *)&addr, sizeof(addr));
- if (ret >= 0)
- return fd;
- ret = -ERRNO_TO_PARA_ERROR(errno);
- close(fd);
- return ret;
-}
-
-/**
- * Create and bind a receiving UDP socket.
- *
- * Bind the created UDP socket to \a hostname, and add multicast membership if
- * hostname is a multicast hostname.
- *
- * \param hostname Name or IPv4 address to receive from.
- * \param port The udp port.
- *
- * \return The fd of the socket on success, negative on errors.
- */
-int create_udp_recv_socket(char *hostname, unsigned short port)
-{
- struct sockaddr_in addr;
- int fd, ret = resolve(hostname, port, &addr);
-
- if (ret < 0)
- memset(&addr.sin_addr, 0, sizeof(addr.sin_addr));
- ret = create_udp_socket(&addr, port, 1);
- if (ret < 0)
- return ret;
- fd = ret;
- ret = bind(fd, (struct sockaddr *)&addr, sizeof(addr));
- if (ret < 0) {
- ret = -ERRNO_TO_PARA_ERROR(errno);
- goto err;
- }
- /* Add multicast membership */
- if (IN_MULTICAST(htonl(addr.sin_addr.s_addr))) {
- struct ip_mreq mreq;
-
- mreq.imr_multiaddr.s_addr = addr.sin_addr.s_addr;
- mreq.imr_interface.s_addr = htonl(INADDR_ANY);
- ret = setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
- &mreq, sizeof(mreq));
- if (ret < 0) {
- ret = -ERRNO_TO_PARA_ERROR(errno);
- goto err;
- }
- }
- return fd;
-err:
- close(fd);
- return ret;
-}
void enable_crypt(int fd, crypt_function *recv_f, crypt_function *send_f,
void *private_data);
void disable_crypt(int fd);
-int create_udp_recv_socket(char *hostname, unsigned short port);
-int create_udp_send_socket(char *hostname, unsigned short port,
- unsigned char ttl);
return NULL;
}
+/*
+ * Perform AF-independent joining of multicast receive addresses.
+ *
+ * \param fd Bound socket descriptor.
+ *
+ * \return Zero if okay, negative on error.
+ */
+static int mcast_receiver_setup(int fd)
+{
+ struct sockaddr_storage ss;
+ socklen_t sslen = sizeof(ss);
+
+ if (getsockname(fd, (struct sockaddr *)&ss, &sslen) < 0)
+ goto err;
+
+ switch (ss.ss_family) {
+ case AF_INET:
+ if (IN_MULTICAST(htonl(((struct sockaddr_in *)&ss)->sin_addr.s_addr))) {
+ struct ip_mreq m4;
+
+ memset(&m4, 0, sizeof(m4));
+ m4.imr_multiaddr = ((struct sockaddr_in *)&ss)->sin_addr;
+ if (setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &m4, sizeof(m4)) < 0)
+ break;
+ }
+ return 0;
+ case AF_INET6:
+ if (IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6 *)&ss)->sin6_addr)) {
+ struct ipv6_mreq m6;
+
+ memset(&m6, 0, sizeof(m6));
+ memcpy(&m6.ipv6mr_multiaddr, &((struct sockaddr_in6 *)&ss)->sin6_addr, 16);
+ if (setsockopt(fd, IPPROTO_IPV6, IPV6_JOIN_GROUP, &m6, sizeof(m6)) < 0)
+ break;
+ }
+ return 0;
+ default:
+ PARA_ERROR_LOG("address family %d not supported", ss.ss_family);
+ return -E_ADDRESS_LOOKUP;
+ }
+err:
+ return -ERRNO_TO_PARA_ERROR(errno);
+}
+
static int udp_recv_open(struct receiver_node *rn)
{
struct private_udp_recv_data *purd;
rn->buf = para_calloc(UDP_RECV_CHUNK_SIZE);
rn->private_data = para_calloc(sizeof(struct private_udp_recv_data));
purd = rn->private_data;
- ret = create_udp_recv_socket(c->host_arg, c->port_arg);
+
+ ret = makesock(AF_UNSPEC, IPPROTO_UDP, 1, c->host_arg, c->port_arg);
if (ret < 0)
goto err;
purd->fd = ret;
+
+ ret = mcast_receiver_setup(purd->fd);
+ if (ret < 0) {
+ close(purd->fd);
+ return ret;
+ }
+
ret = mark_fd_nonblocking(purd->fd);
if (ret < 0)
goto err;
free(ut);
}
+/**
+ * Perform AF-independent multicast sender setup.
+ *
+ * \param fd The connected socket descriptor.
+ * \param ttl UDPv4 multicast TTL or UDPv6 multicast number of hops.
+ * Use -1 to mean default, 0..255 otherwise.
+
+ ** \return Zero if okay, negative on error.
+ */
+static int mcast_sender_setup(struct udp_target *ut, int ttl)
+{
+ struct sockaddr_storage ss;
+ socklen_t sslen = sizeof(ss);
+
+ const int on = 1;
+
+ if (getpeername(ut->fd, (struct sockaddr *)&ss, &sslen) < 0)
+ goto err;
+
+ /* RFC 3493, 5.2: -1 means 'use kernel default' */
+ if (ttl < 0 || ttl > 255)
+ ttl = -1;
+
+ switch (ss.ss_family) {
+ case AF_INET:
+ if (!IN_MULTICAST(htonl(((struct sockaddr_in *)&ss)->sin_addr.s_addr)))
+ return 0;
+ /*
+ * Enable receiving multicast messages generated on the local host
+ * At least on Linux, this is enabled by default.
+ */
+ if (setsockopt(ut->fd, IPPROTO_IP, IP_MULTICAST_LOOP, &on, sizeof(on)) < 0)
+ break;
+
+ /* Default: use local subnet (do not flood out into the WAN) */
+ if (ttl == -1)
+ ttl = 1;
+ if (setsockopt(ut->fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)) < 0)
+ break;
+ return 0;
+ case AF_INET6:
+ if (!IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6 *)&ss)->sin6_addr))
+ return 0;
+ if (setsockopt(ut->fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &on, sizeof(on)) < 0)
+ break;
+ if (setsockopt(ut->fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl)) < 0)
+ break;
+ return 0;
+ default:
+ PARA_ERROR_LOG("address family %d not supported", ss.ss_family);
+ return -E_ADDRESS_LOOKUP;
+ }
+err:
+ return -ERRNO_TO_PARA_ERROR(errno);
+}
+
/** The maximal size of the per-target chunk queue. */
#define UDP_CQ_BYTES 40000
if (ut->fd >= 0) /* nothing to do */
return 0;
- ret = create_udp_send_socket(TARGET_ADDR(ut), ut->port,
- conf.udp_ttl_arg);
+
+ ret = makesock(AF_UNSPEC, IPPROTO_UDP, 0, TARGET_ADDR(ut), ut->port);
if (ret < 0)
return ret;
ut->fd = ret;
+
+ ret = mcast_sender_setup(ut, conf.udp_ttl_arg);
+ if (ret < 0) {
+ close(ut->fd);
+ return ret;
+ }
+
ret = mark_fd_nonblocking(ut->fd);
if (ret < 0) {
close(ut->fd);
projects / paraslash.git / commitdiff