/* * (C) 2011-2017 by Harald Welte * * All Rights Reserved * * SPDX-License-Identifier: GPL-2.0+ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program 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 General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. * */ #include "../config.h" /*! \addtogroup socket * @{ * Osmocom socket convenience functions. * * \file socket.c */ #ifdef HAVE_SYS_SOCKET_H #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static struct addrinfo *addrinfo_helper(uint16_t family, uint16_t type, uint8_t proto, const char *host, uint16_t port, bool passive) { struct addrinfo hints, *result; char portbuf[6]; int rc; snprintf(portbuf, sizeof(portbuf), "%u", port); memset(&hints, 0, sizeof(struct addrinfo)); hints.ai_family = family; if (type == SOCK_RAW) { /* Workaround for glibc, that returns EAI_SERVICE (-8) if * SOCK_RAW and IPPROTO_GRE is used. */ hints.ai_socktype = SOCK_DGRAM; hints.ai_protocol = IPPROTO_UDP; } else { hints.ai_socktype = type; hints.ai_protocol = proto; } if (passive) hints.ai_flags |= AI_PASSIVE; rc = getaddrinfo(host, portbuf, &hints, &result); if (rc != 0) { LOGP(DLGLOBAL, LOGL_ERROR, "getaddrinfo returned NULL: %s:%u: %s\n", host, port, strerror(errno)); return NULL; } return result; } static int socket_helper(const struct addrinfo *rp, unsigned int flags) { int sfd, on = 1; sfd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol); if (sfd == -1) { LOGP(DLGLOBAL, LOGL_ERROR, "unable to create socket: %s\n", strerror(errno)); return sfd; } if (flags & OSMO_SOCK_F_NONBLOCK) { if (ioctl(sfd, FIONBIO, (unsigned char *)&on) < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "cannot set this socket unblocking: %s\n", strerror(errno)); close(sfd); sfd = -EINVAL; } } return sfd; } static int osmo_sock_init_tail(int fd, uint16_t type, unsigned int flags) { int rc; /* Make sure to call 'listen' on a bound, connection-oriented sock */ if ((flags & (OSMO_SOCK_F_BIND|OSMO_SOCK_F_CONNECT)) == OSMO_SOCK_F_BIND) { switch (type) { case SOCK_STREAM: case SOCK_SEQPACKET: rc = listen(fd, 10); if (rc < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "unable to listen on socket: %s\n", strerror(errno)); return rc; } break; } } if (flags & OSMO_SOCK_F_NO_MCAST_LOOP) { rc = osmo_sock_mcast_loop_set(fd, false); if (rc < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "unable to disable multicast loop: %s\n", strerror(errno)); return rc; } } if (flags & OSMO_SOCK_F_NO_MCAST_ALL) { rc = osmo_sock_mcast_all_set(fd, false); if (rc < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "unable to disable receive of all multicast: %s\n", strerror(errno)); /* do not abort here, as this is just an * optional additional optimization that only * exists on Linux only */ } } return 0; } /*! Initialize a socket (including bind and/or connect) * \param[in] family Address Family like AF_INET, AF_INET6, AF_UNSPEC * \param[in] type Socket type like SOCK_DGRAM, SOCK_STREAM * \param[in] proto Protocol like IPPROTO_TCP, IPPROTO_UDP * \param[in] local_host local host name or IP address in string form * \param[in] local_port local port number in host byte order * \param[in] remote_host remote host name or IP address in string form * \param[in] remote_port remote port number in host byte order * \param[in] flags flags like \ref OSMO_SOCK_F_CONNECT * \returns socket file descriptor on success; negative on error * * This function creates a new socket of the designated \a family, \a * type and \a proto and optionally binds it to the \a local_host and \a * local_port as well as optionally connects it to the \a remote_host * and \q remote_port, depending on the value * of \a flags parameter. * * As opposed to \ref osmo_sock_init(), this function allows to combine * the \ref OSMO_SOCK_F_BIND and \ref OSMO_SOCK_F_CONNECT flags. This * is useful if you want to connect to a remote host/port, but still * want to bind that socket to either a specific local alias IP and/or a * specific local source port. * * You must specify either \ref OSMO_SOCK_F_BIND, or \ref * OSMO_SOCK_F_CONNECT, or both. * * If \ref OSMO_SOCK_F_NONBLOCK is specified, the socket will be set to * non-blocking mode. */ int osmo_sock_init2(uint16_t family, uint16_t type, uint8_t proto, const char *local_host, uint16_t local_port, const char *remote_host, uint16_t remote_port, unsigned int flags) { struct addrinfo *result, *rp; int sfd = -1, rc, on = 1; if ((flags & (OSMO_SOCK_F_BIND | OSMO_SOCK_F_CONNECT)) == 0) { LOGP(DLGLOBAL, LOGL_ERROR, "invalid: you have to specify either " "BIND or CONNECT flags\n"); return -EINVAL; } /* figure out local side of socket */ if (flags & OSMO_SOCK_F_BIND) { result = addrinfo_helper(family, type, proto, local_host, local_port, true); if (!result) return -EINVAL; for (rp = result; rp != NULL; rp = rp->ai_next) { /* Workaround for glibc again */ if (type == SOCK_RAW) { rp->ai_socktype = SOCK_RAW; rp->ai_protocol = proto; } sfd = socket_helper(rp, flags); if (sfd < 0) continue; if (proto != IPPROTO_UDP || flags & OSMO_SOCK_F_UDP_REUSEADDR) { rc = setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)); if (rc < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "cannot setsockopt socket:" " %s:%u: %s\n", local_host, local_port, strerror(errno)); close(sfd); continue; } } if (bind(sfd, rp->ai_addr, rp->ai_addrlen) == -1) { LOGP(DLGLOBAL, LOGL_ERROR, "unable to bind socket: %s:%u: %s\n", local_host, local_port, strerror(errno)); close(sfd); continue; } break; } freeaddrinfo(result); if (rp == NULL) { LOGP(DLGLOBAL, LOGL_ERROR, "no suitable local addr found for: %s:%u\n", local_host, local_port); return -ENODEV; } } /* Reached this point, if OSMO_SOCK_F_BIND then sfd is valid (>=0) or it was already closed and func returned. If OSMO_SOCK_F_BIND is not set, then sfd = -1 */ /* figure out remote side of socket */ if (flags & OSMO_SOCK_F_CONNECT) { result = addrinfo_helper(family, type, proto, remote_host, remote_port, false); if (!result) { if (sfd >= 0) close(sfd); return -EINVAL; } for (rp = result; rp != NULL; rp = rp->ai_next) { /* Workaround for glibc again */ if (type == SOCK_RAW) { rp->ai_socktype = SOCK_RAW; rp->ai_protocol = proto; } if (sfd < 0) { sfd = socket_helper(rp, flags); if (sfd < 0) continue; } rc = connect(sfd, rp->ai_addr, rp->ai_addrlen); if (rc != 0 && errno != EINPROGRESS) { LOGP(DLGLOBAL, LOGL_ERROR, "unable to connect socket: %s:%u: %s\n", remote_host, remote_port, strerror(errno)); /* We want to maintain the bind socket if bind was enabled */ if (!(flags & OSMO_SOCK_F_BIND)) { close(sfd); sfd = -1; } continue; } break; } freeaddrinfo(result); if (rp == NULL) { LOGP(DLGLOBAL, LOGL_ERROR, "no suitable remote addr found for: %s:%u\n", remote_host, remote_port); if (sfd >= 0) close(sfd); return -ENODEV; } } rc = osmo_sock_init_tail(sfd, type, flags); if (rc < 0) { close(sfd); sfd = -1; } return sfd; } /*! Initialize a socket (including bind/connect) * \param[in] family Address Family like AF_INET, AF_INET6, AF_UNSPEC * \param[in] type Socket type like SOCK_DGRAM, SOCK_STREAM * \param[in] proto Protocol like IPPROTO_TCP, IPPROTO_UDP * \param[in] host remote host name or IP address in string form * \param[in] port remote port number in host byte order * \param[in] flags flags like \ref OSMO_SOCK_F_CONNECT * \returns socket file descriptor on success; negative on error * * This function creates a new socket of the designated \a family, \a * type and \a proto and optionally binds or connects it, depending on * the value of \a flags parameter. */ int osmo_sock_init(uint16_t family, uint16_t type, uint8_t proto, const char *host, uint16_t port, unsigned int flags) { struct addrinfo *result, *rp; int sfd, rc, on = 1; if ((flags & (OSMO_SOCK_F_BIND | OSMO_SOCK_F_CONNECT)) == (OSMO_SOCK_F_BIND | OSMO_SOCK_F_CONNECT)) { LOGP(DLGLOBAL, LOGL_ERROR, "invalid: both bind and connect flags set:" " %s:%u\n", host, port); return -EINVAL; } result = addrinfo_helper(family, type, proto, host, port, flags & OSMO_SOCK_F_BIND); if (!result) { LOGP(DLGLOBAL, LOGL_ERROR, "getaddrinfo returned NULL: %s:%u: %s\n", host, port, strerror(errno)); return -EINVAL; } for (rp = result; rp != NULL; rp = rp->ai_next) { /* Workaround for glibc again */ if (type == SOCK_RAW) { rp->ai_socktype = SOCK_RAW; rp->ai_protocol = proto; } sfd = socket_helper(rp, flags); if (sfd == -1) continue; if (flags & OSMO_SOCK_F_CONNECT) { rc = connect(sfd, rp->ai_addr, rp->ai_addrlen); if (rc != 0 && errno != EINPROGRESS) { close(sfd); continue; } } else { if (proto != IPPROTO_UDP || flags & OSMO_SOCK_F_UDP_REUSEADDR) { rc = setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)); if (rc < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "cannot setsockopt socket:" " %s:%u: %s\n", host, port, strerror(errno)); close(sfd); continue; } } if (bind(sfd, rp->ai_addr, rp->ai_addrlen) == -1) { LOGP(DLGLOBAL, LOGL_ERROR, "unable to bind socket:" "%s:%u: %s\n", host, port, strerror(errno)); close(sfd); continue; } } break; } freeaddrinfo(result); if (rp == NULL) { LOGP(DLGLOBAL, LOGL_ERROR, "no suitable addr found for: %s:%u\n", host, port); return -ENODEV; } if (proto != IPPROTO_UDP || flags & OSMO_SOCK_F_UDP_REUSEADDR) { rc = setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)); if (rc < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "cannot setsockopt socket: %s:%u: %s\n", host, port, strerror(errno)); close(sfd); sfd = -1; } } rc = osmo_sock_init_tail(sfd, type, flags); if (rc < 0) { close(sfd); sfd = -1; } return sfd; } /*! fill \ref osmo_fd for a give sfd * \param[out] ofd file descriptor (will be filled in) * \param[in] sfd socket file descriptor * \returns socket fd on success; negative on error * * This function fills the \a ofd structure. */ static inline int osmo_fd_init_ofd(struct osmo_fd *ofd, int sfd) { int rc; if (sfd < 0) return sfd; ofd->fd = sfd; ofd->when = OSMO_FD_READ; rc = osmo_fd_register(ofd); if (rc < 0) { close(sfd); return rc; } return sfd; } /*! Initialize a socket and fill \ref osmo_fd * \param[out] ofd file descriptor (will be filled in) * \param[in] family Address Family like AF_INET, AF_INET6, AF_UNSPEC * \param[in] type Socket type like SOCK_DGRAM, SOCK_STREAM * \param[in] proto Protocol like IPPROTO_TCP, IPPROTO_UDP * \param[in] host remote host name or IP address in string form * \param[in] port remote port number in host byte order * \param[in] flags flags like \ref OSMO_SOCK_F_CONNECT * \returns socket fd on success; negative on error * * This function creates (and optionall binds/connects) a socket using * \ref osmo_sock_init, but also fills the \a ofd structure. */ int osmo_sock_init_ofd(struct osmo_fd *ofd, int family, int type, int proto, const char *host, uint16_t port, unsigned int flags) { return osmo_fd_init_ofd(ofd, osmo_sock_init(family, type, proto, host, port, flags)); } /*! Initialize a socket and fill \ref osmo_fd * \param[out] ofd file descriptor (will be filled in) * \param[in] family Address Family like AF_INET, AF_INET6, AF_UNSPEC * \param[in] type Socket type like SOCK_DGRAM, SOCK_STREAM * \param[in] proto Protocol like IPPROTO_TCP, IPPROTO_UDP * \param[in] local_host local host name or IP address in string form * \param[in] local_port local port number in host byte order * \param[in] remote_host remote host name or IP address in string form * \param[in] remote_port remote port number in host byte order * \param[in] flags flags like \ref OSMO_SOCK_F_CONNECT * \returns socket fd on success; negative on error * * This function creates (and optionall binds/connects) a socket using * \ref osmo_sock_init2, but also fills the \a ofd structure. */ int osmo_sock_init2_ofd(struct osmo_fd *ofd, int family, int type, int proto, const char *local_host, uint16_t local_port, const char *remote_host, uint16_t remote_port, unsigned int flags) { return osmo_fd_init_ofd(ofd, osmo_sock_init2(family, type, proto, local_host, local_port, remote_host, remote_port, flags)); } /*! Initialize a socket and fill \ref sockaddr * \param[out] ss socket address (will be filled in) * \param[in] type Socket type like SOCK_DGRAM, SOCK_STREAM * \param[in] proto Protocol like IPPROTO_TCP, IPPROTO_UDP * \param[in] flags flags like \ref OSMO_SOCK_F_CONNECT * \returns socket fd on success; negative on error * * This function creates (and optionall binds/connects) a socket using * \ref osmo_sock_init, but also fills the \a ss structure. */ int osmo_sock_init_sa(struct sockaddr *ss, uint16_t type, uint8_t proto, unsigned int flags) { char host[NI_MAXHOST]; uint16_t port; struct sockaddr_in *sin; struct sockaddr_in6 *sin6; int s, sa_len; /* determine port and host from ss */ switch (ss->sa_family) { case AF_INET: sin = (struct sockaddr_in *) ss; sa_len = sizeof(struct sockaddr_in); port = ntohs(sin->sin_port); break; case AF_INET6: sin6 = (struct sockaddr_in6 *) ss; sa_len = sizeof(struct sockaddr_in6); port = ntohs(sin6->sin6_port); break; default: return -EINVAL; } s = getnameinfo(ss, sa_len, host, NI_MAXHOST, NULL, 0, NI_NUMERICHOST); if (s != 0) { LOGP(DLGLOBAL, LOGL_ERROR, "getnameinfo failed:" " %s\n", strerror(errno)); return s; } return osmo_sock_init(ss->sa_family, type, proto, host, port, flags); } static int sockaddr_equal(const struct sockaddr *a, const struct sockaddr *b, unsigned int len) { struct sockaddr_in *sin_a, *sin_b; struct sockaddr_in6 *sin6_a, *sin6_b; if (a->sa_family != b->sa_family) return 0; switch (a->sa_family) { case AF_INET: sin_a = (struct sockaddr_in *)a; sin_b = (struct sockaddr_in *)b; if (!memcmp(&sin_a->sin_addr, &sin_b->sin_addr, sizeof(struct in_addr))) return 1; break; case AF_INET6: sin6_a = (struct sockaddr_in6 *)a; sin6_b = (struct sockaddr_in6 *)b; if (!memcmp(&sin6_a->sin6_addr, &sin6_b->sin6_addr, sizeof(struct in6_addr))) return 1; break; } return 0; } /*! Determine if the given address is a local address * \param[in] addr Socket Address * \param[in] addrlen Length of socket address in bytes * \returns 1 if address is local, 0 otherwise. */ int osmo_sockaddr_is_local(struct sockaddr *addr, unsigned int addrlen) { struct ifaddrs *ifaddr, *ifa; if (getifaddrs(&ifaddr) == -1) { LOGP(DLGLOBAL, LOGL_ERROR, "getifaddrs:" " %s\n", strerror(errno)); return -EIO; } for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) { if (!ifa->ifa_addr) continue; if (sockaddr_equal(ifa->ifa_addr, addr, addrlen)) { freeifaddrs(ifaddr); return 1; } } freeifaddrs(ifaddr); return 0; } /*! Convert sockaddr_in to IP address as char string and port as uint16_t. * \param[out] addr String buffer to write IP address to, or NULL. * \param[out] addr_len Size of \a addr. * \param[out] port Pointer to uint16_t to write the port number to, or NULL. * \param[in] sin Sockaddr to convert. * \returns the required string buffer size, like osmo_strlcpy(), or 0 if \a addr is NULL. */ size_t osmo_sockaddr_in_to_str_and_uint(char *addr, unsigned int addr_len, uint16_t *port, const struct sockaddr_in *sin) { if (port) *port = ntohs(sin->sin_port); if (addr) return osmo_strlcpy(addr, inet_ntoa(sin->sin_addr), addr_len); return 0; } /*! Convert sockaddr to IP address as char string and port as uint16_t. * \param[out] addr String buffer to write IP address to, or NULL. * \param[out] addr_len Size of \a addr. * \param[out] port Pointer to uint16_t to write the port number to, or NULL. * \param[in] sa Sockaddr to convert. * \returns the required string buffer size, like osmo_strlcpy(), or 0 if \a addr is NULL. */ unsigned int osmo_sockaddr_to_str_and_uint(char *addr, unsigned int addr_len, uint16_t *port, const struct sockaddr *sa) { const struct sockaddr_in *sin = (const struct sockaddr_in *)sa; return osmo_sockaddr_in_to_str_and_uint(addr, addr_len, port, sin); } /*! Initialize a unix domain socket (including bind/connect) * \param[in] type Socket type like SOCK_DGRAM, SOCK_STREAM * \param[in] proto Protocol like IPPROTO_TCP, IPPROTO_UDP * \param[in] socket_path path to identify the socket * \param[in] flags flags like \ref OSMO_SOCK_F_CONNECT * \returns socket fd on success; negative on error * * This function creates a new unix domain socket, \a * type and \a proto and optionally binds or connects it, depending on * the value of \a flags parameter. */ int osmo_sock_unix_init(uint16_t type, uint8_t proto, const char *socket_path, unsigned int flags) { struct sockaddr_un local; int sfd, rc, on = 1; unsigned int namelen; if ((flags & (OSMO_SOCK_F_BIND | OSMO_SOCK_F_CONNECT)) == (OSMO_SOCK_F_BIND | OSMO_SOCK_F_CONNECT)) return -EINVAL; local.sun_family = AF_UNIX; /* When an AF_UNIX socket is bound, sun_path should be NUL-terminated. See unix(7) man page. */ if (osmo_strlcpy(local.sun_path, socket_path, sizeof(local.sun_path)) >= sizeof(local.sun_path)) { LOGP(DLGLOBAL, LOGL_ERROR, "Socket path exceeds maximum length of %zd bytes: %s\n", sizeof(local.sun_path), socket_path); return -ENOSPC; } #if defined(BSD44SOCKETS) || defined(__UNIXWARE__) local.sun_len = strlen(local.sun_path); #endif #if defined(BSD44SOCKETS) || defined(SUN_LEN) namelen = SUN_LEN(&local); #else namelen = strlen(local.sun_path) + offsetof(struct sockaddr_un, sun_path); #endif sfd = socket(AF_UNIX, type, proto); if (sfd < 0) return -1; if (flags & OSMO_SOCK_F_CONNECT) { rc = connect(sfd, (struct sockaddr *)&local, namelen); if (rc < 0) goto err; } else { unlink(local.sun_path); rc = bind(sfd, (struct sockaddr *)&local, namelen); if (rc < 0) goto err; } if (flags & OSMO_SOCK_F_NONBLOCK) { if (ioctl(sfd, FIONBIO, (unsigned char *)&on) < 0) { LOGP(DLGLOBAL, LOGL_ERROR, "cannot set this socket unblocking: %s\n", strerror(errno)); close(sfd); return -EINVAL; } } rc = osmo_sock_init_tail(sfd, type, flags); if (rc < 0) { close(sfd); sfd = -1; } return sfd; err: close(sfd); return -1; } /*! Initialize a unix domain socket and fill \ref osmo_fd * \param[out] ofd file descriptor (will be filled in) * \param[in] type Socket type like SOCK_DGRAM, SOCK_STREAM * \param[in] proto Protocol like IPPROTO_TCP, IPPROTO_UDP * \param[in] socket_path path to identify the socket * \param[in] flags flags like \ref OSMO_SOCK_F_CONNECT * \returns socket fd on success; negative on error * * This function creates (and optionall binds/connects) a socket using * \ref osmo_sock_unix_init, but also fills the \a ofd structure. */ int osmo_sock_unix_init_ofd(struct osmo_fd *ofd, uint16_t type, uint8_t proto, const char *socket_path, unsigned int flags) { return osmo_fd_init_ofd(ofd, osmo_sock_unix_init(type, proto, socket_path, flags)); } /*! Get the IP and/or port number on socket in separate string buffers. * \param[in] fd file descriptor of socket * \param[out] ip IP address (will be filled in when not NULL) * \param[in] ip_len length of the ip buffer * \param[out] port number (will be filled in when not NULL) * \param[in] port_len length of the port buffer * \param[in] local (true) or remote (false) name will get looked at * \returns 0 on success; negative otherwise */ int osmo_sock_get_ip_and_port(int fd, char *ip, size_t ip_len, char *port, size_t port_len, bool local) { struct sockaddr sa; socklen_t len = sizeof(sa); char ipbuf[INET6_ADDRSTRLEN], portbuf[6]; int rc; rc = local ? getsockname(fd, &sa, &len) : getpeername(fd, &sa, &len); if (rc < 0) return rc; rc = getnameinfo(&sa, len, ipbuf, sizeof(ipbuf), portbuf, sizeof(portbuf), NI_NUMERICHOST | NI_NUMERICSERV); if (rc < 0) return rc; if (ip) strncpy(ip, ipbuf, ip_len); if (port) strncpy(port, portbuf, port_len); return 0; } /*! Get local IP address on socket * \param[in] fd file descriptor of socket * \param[out] ip IP address (will be filled in) * \param[in] len length of the output buffer * \returns 0 on success; negative otherwise */ int osmo_sock_get_local_ip(int fd, char *ip, size_t len) { return osmo_sock_get_ip_and_port(fd, ip, len, NULL, 0, true); } /*! Get local port on socket * \param[in] fd file descriptor of socket * \param[out] port number (will be filled in) * \param[in] len length of the output buffer * \returns 0 on success; negative otherwise */ int osmo_sock_get_local_ip_port(int fd, char *port, size_t len) { return osmo_sock_get_ip_and_port(fd, NULL, 0, port, len, true); } /*! Get remote IP address on socket * \param[in] fd file descriptor of socket * \param[out] ip IP address (will be filled in) * \param[in] len length of the output buffer * \returns 0 on success; negative otherwise */ int osmo_sock_get_remote_ip(int fd, char *ip, size_t len) { return osmo_sock_get_ip_and_port(fd, ip, len, NULL, 0, false); } /*! Get remote port on socket * \param[in] fd file descriptor of socket * \param[out] port number (will be filled in) * \param[in] len length of the output buffer * \returns 0 on success; negative otherwise */ int osmo_sock_get_remote_ip_port(int fd, char *port, size_t len) { return osmo_sock_get_ip_and_port(fd, NULL, 0, port, len, false); } /*! Get address/port information on socket in dyn-alloc string like "(r=1.2.3.4:5<->l=6.7.8.9:10)". * Usually, it is better to use osmo_sock_get_name2() for a static string buffer or osmo_sock_get_name_buf() for a * caller provided string buffer, to avoid the dynamic talloc allocation. * \param[in] ctx talloc context from which to allocate string buffer * \param[in] fd file descriptor of socket * \returns string identifying the connection of this socket, talloc'd from ctx. */ char *osmo_sock_get_name(const void *ctx, int fd) { char str[OSMO_SOCK_NAME_MAXLEN]; int rc; rc = osmo_sock_get_name_buf(str, sizeof(str), fd); if (rc <= 0) return NULL; return talloc_asprintf(ctx, "(%s)", str); } /*! Get address/port information on socket in provided string buffer, like "r=1.2.3.4:5<->l=6.7.8.9:10". * This does not include braces like osmo_sock_get_name(). * \param[out] str Destination string buffer. * \param[in] str_len sizeof(str). * \param[in] fd File descriptor of socket. * \return String length as returned by snprintf(), or negative on error. */ int osmo_sock_get_name_buf(char *str, size_t str_len, int fd) { char hostbuf_l[INET6_ADDRSTRLEN], hostbuf_r[INET6_ADDRSTRLEN]; char portbuf_l[6], portbuf_r[6]; int rc; /* get local */ if ((rc = osmo_sock_get_ip_and_port(fd, hostbuf_l, sizeof(hostbuf_l), portbuf_l, sizeof(portbuf_l), true))) return rc; /* get remote */ if (osmo_sock_get_ip_and_port(fd, hostbuf_r, sizeof(hostbuf_r), portbuf_r, sizeof(portbuf_r), false) != 0) return snprintf(str, str_len, "r=NULL<->l=%s:%s", hostbuf_l, portbuf_l); return snprintf(str, str_len, "r=%s:%s<->l=%s:%s", hostbuf_r, portbuf_r, hostbuf_l, portbuf_l); } /*! Get address/port information on socket in static string, like "r=1.2.3.4:5<->l=6.7.8.9:10". * This does not include braces like osmo_sock_get_name(). * \param[in] fd File descriptor of socket. * \return Static string buffer containing the result. */ const char *osmo_sock_get_name2(int fd) { static char str[OSMO_SOCK_NAME_MAXLEN]; osmo_sock_get_name_buf(str, sizeof(str), fd); return str; } /*! Get address/port information on socket in static string, like "r=1.2.3.4:5<->l=6.7.8.9:10". * This does not include braces like osmo_sock_get_name(). * \param[in] fd File descriptor of socket. * \return Static string buffer containing the result. */ char *osmo_sock_get_name2_c(const void *ctx, int fd) { char *str = talloc_size(ctx, OSMO_SOCK_NAME_MAXLEN); if (!str) return NULL; osmo_sock_get_name_buf(str, sizeof(str), fd); return str; } static int sock_get_domain(int fd) { int domain; #ifdef SO_DOMAIN socklen_t dom_len = sizeof(domain); int rc; rc = getsockopt(fd, SOL_SOCKET, SO_DOMAIN, &domain, &dom_len); if (rc < 0) return rc; #else /* This of course sucks, but what shall we do on OSs like * FreeBSD that don't seem to expose a method by which one can * learn the address family of a socket? */ domain = AF_INET; #endif return domain; } /*! Activate or de-activate local loop-back of transmitted multicast packets * \param[in] fd file descriptor of related socket * \param[in] enable Enable (true) or disable (false) loop-back * \returns 0 on success; negative otherwise */ int osmo_sock_mcast_loop_set(int fd, bool enable) { int domain, loop = 0; if (enable) loop = 1; domain = sock_get_domain(fd); if (domain < 0) return domain; switch (domain) { case AF_INET: return setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP, &loop, sizeof(loop)); case AF_INET6: return setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &loop, sizeof(loop)); default: return -EINVAL; } } /*! Set the TTL of outbound multicast packets * \param[in] fd file descriptor of related socket * \param[in] ttl TTL of to-be-sent multicast packets * \returns 0 on success; negative otherwise */ int osmo_sock_mcast_ttl_set(int fd, uint8_t ttl) { int domain, ttli = ttl; domain = sock_get_domain(fd); if (domain < 0) return domain; switch (domain) { case AF_INET: return setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttli, sizeof(ttli)); case AF_INET6: return setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttli, sizeof(ttli)); default: return -EINVAL; } } /*! Enable/disable receiving all multicast packets, even for non-subscribed groups * \param[in] fd file descriptor of related socket * \param[in] enable Enable or Disable receiving of all packets * \returns 0 on success; negative otherwise */ int osmo_sock_mcast_all_set(int fd, bool enable) { int domain, all = 0; if (enable) all = 1; domain = sock_get_domain(fd); if (domain < 0) return domain; switch (domain) { case AF_INET: #ifdef IP_MULTICAST_ALL return setsockopt(fd, IPPROTO_IP, IP_MULTICAST_ALL, &all, sizeof(all)); #endif case AF_INET6: /* there seems no equivalent ?!? */ default: return -EINVAL; } } /* FreeBSD calls the socket option differently */ #if !defined(IPV6_ADD_MEMBERSHIP) && defined(IPV6_JOIN_GROUP) #define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP #endif /*! Subscribe to the given IP multicast group * \param[in] fd file descriptor of related scoket * \param[in] grp_addr ASCII representation of the multicast group address * \returns 0 on success; negative otherwise */ int osmo_sock_mcast_subscribe(int fd, const char *grp_addr) { int rc, domain; struct ip_mreq mreq; struct ipv6_mreq mreq6; struct in6_addr i6a; domain = sock_get_domain(fd); if (domain < 0) return domain; switch (domain) { case AF_INET: memset(&mreq, 0, sizeof(mreq)); mreq.imr_multiaddr.s_addr = inet_addr(grp_addr); mreq.imr_interface.s_addr = htonl(INADDR_ANY); return setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq)); #ifdef IPV6_ADD_MEMBERSHIP case AF_INET6: memset(&mreq6, 0, sizeof(mreq6)); rc = inet_pton(AF_INET6, grp_addr, (void *)&i6a); if (rc < 0) return -EINVAL; mreq6.ipv6mr_multiaddr = i6a; return setsockopt(fd, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq6, sizeof(mreq6)); #endif default: return -EINVAL; } } /*! Determine the matching local IP-address for a given remote IP-Address. * \param[out] local_ip caller provided memory for resulting local IP-address * \param[in] remote_ip remote IP-address * \param[in] fd file descriptor of related scoket * \returns 0 on success; negative otherwise * * The function accepts IPv4 and IPv6 address strings. The caller must provide * at least INET6_ADDRSTRLEN bytes for local_ip if an IPv6 is expected as * as result. For IPv4 addresses the required amount is INET_ADDRSTRLEN. */ int osmo_sock_local_ip(char *local_ip, const char *remote_ip) { int sfd; int rc; struct addrinfo addrinfo_hint; struct addrinfo *addrinfo = NULL; struct sockaddr_in local_addr; socklen_t local_addr_len; uint16_t family; /* Find out the address family (AF_INET or AF_INET6?) */ memset(&addrinfo_hint, '\0', sizeof(addrinfo_hint)); addrinfo_hint.ai_family = PF_UNSPEC; addrinfo_hint.ai_flags = AI_NUMERICHOST; rc = getaddrinfo(remote_ip, NULL, &addrinfo_hint, &addrinfo); if (rc) return -EINVAL; family = addrinfo->ai_family; freeaddrinfo(addrinfo); /* Connect a dummy socket to trick the kernel into determining the * ip-address of the interface that would be used if we would send * out an actual packet */ sfd = osmo_sock_init2(family, SOCK_DGRAM, IPPROTO_UDP, NULL, 0, remote_ip, 0, OSMO_SOCK_F_CONNECT); if (sfd < 0) return -EINVAL; /* Request the IP address of the interface that the kernel has * actually choosen. */ memset(&local_addr, 0, sizeof(local_addr)); local_addr_len = sizeof(local_addr); rc = getsockname(sfd, (struct sockaddr *)&local_addr, &local_addr_len); close(sfd); if (rc < 0) return -EINVAL; if (local_addr.sin_family == AF_INET) inet_ntop(AF_INET, &local_addr.sin_addr, local_ip, INET_ADDRSTRLEN); else if (local_addr.sin_family == AF_INET6) inet_ntop(AF_INET6, &local_addr.sin_addr, local_ip, INET6_ADDRSTRLEN); else return -EINVAL; return 0; } #endif /* HAVE_SYS_SOCKET_H */ /*! @} */