/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ /*** This file is part of systemd. Copyright 2010 Lennart Poettering systemd 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. systemd 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 systemd; If not, see <http://www.gnu.org/licenses/>. ***/ #include <assert.h> #include <string.h> #include <unistd.h> #include <errno.h> #include <stdlib.h> #include <arpa/inet.h> #include <stdio.h> #include <net/if.h> #include <sys/types.h> #include <sys/stat.h> #include <stddef.h> #include <sys/ioctl.h> #include "macro.h" #include "util.h" #include "mkdir.h" #include "path-util.h" #include "socket-util.h" #include "missing.h" #include "fileio.h" int socket_address_parse(SocketAddress *a, const char *s) { char *e, *n; unsigned u; int r; assert(a); assert(s); zero(*a); a->type = SOCK_STREAM; if (*s == '[') { /* IPv6 in [x:.....:z]:p notation */ if (!socket_ipv6_is_supported()) { log_warning("Binding to IPv6 address not available since kernel does not support IPv6."); return -EAFNOSUPPORT; } e = strchr(s+1, ']'); if (!e) return -EINVAL; n = strndupa(s+1, e-s-1); errno = 0; if (inet_pton(AF_INET6, n, &a->sockaddr.in6.sin6_addr) <= 0) return errno > 0 ? -errno : -EINVAL; e++; if (*e != ':') return -EINVAL; e++; r = safe_atou(e, &u); if (r < 0) return r; if (u <= 0 || u > 0xFFFF) return -EINVAL; a->sockaddr.in6.sin6_family = AF_INET6; a->sockaddr.in6.sin6_port = htons((uint16_t) u); a->size = sizeof(struct sockaddr_in6); } else if (*s == '/') { /* AF_UNIX socket */ size_t l; l = strlen(s); if (l >= sizeof(a->sockaddr.un.sun_path)) return -EINVAL; a->sockaddr.un.sun_family = AF_UNIX; memcpy(a->sockaddr.un.sun_path, s, l); a->size = offsetof(struct sockaddr_un, sun_path) + l + 1; } else if (*s == '@') { /* Abstract AF_UNIX socket */ size_t l; l = strlen(s+1); if (l >= sizeof(a->sockaddr.un.sun_path) - 1) return -EINVAL; a->sockaddr.un.sun_family = AF_UNIX; memcpy(a->sockaddr.un.sun_path+1, s+1, l); a->size = offsetof(struct sockaddr_un, sun_path) + 1 + l; } else { e = strchr(s, ':'); if (e) { r = safe_atou(e+1, &u); if (r < 0) return r; if (u <= 0 || u > 0xFFFF) return -EINVAL; n = strndupa(s, e-s); /* IPv4 in w.x.y.z:p notation? */ r = inet_pton(AF_INET, n, &a->sockaddr.in.sin_addr); if (r < 0) return -errno; if (r > 0) { /* Gotcha, it's a traditional IPv4 address */ a->sockaddr.in.sin_family = AF_INET; a->sockaddr.in.sin_port = htons((uint16_t) u); a->size = sizeof(struct sockaddr_in); } else { unsigned idx; if (strlen(n) > IF_NAMESIZE-1) return -EINVAL; /* Uh, our last resort, an interface name */ idx = if_nametoindex(n); if (idx == 0) return -EINVAL; if (!socket_ipv6_is_supported()) { log_warning("Binding to interface is not available since kernel does not support IPv6."); return -EAFNOSUPPORT; } a->sockaddr.in6.sin6_family = AF_INET6; a->sockaddr.in6.sin6_port = htons((uint16_t) u); a->sockaddr.in6.sin6_scope_id = idx; a->sockaddr.in6.sin6_addr = in6addr_any; a->size = sizeof(struct sockaddr_in6); } } else { /* Just a port */ r = safe_atou(s, &u); if (r < 0) return r; if (u <= 0 || u > 0xFFFF) return -EINVAL; if (socket_ipv6_is_supported()) { a->sockaddr.in6.sin6_family = AF_INET6; a->sockaddr.in6.sin6_port = htons((uint16_t) u); a->sockaddr.in6.sin6_addr = in6addr_any; a->size = sizeof(struct sockaddr_in6); } else { a->sockaddr.in.sin_family = AF_INET; a->sockaddr.in.sin_port = htons((uint16_t) u); a->sockaddr.in.sin_addr.s_addr = INADDR_ANY; a->size = sizeof(struct sockaddr_in); } } } return 0; } int socket_address_parse_netlink(SocketAddress *a, const char *s) { int family; unsigned group = 0; _cleanup_free_ char *sfamily = NULL; assert(a); assert(s); zero(*a); a->type = SOCK_RAW; errno = 0; if (sscanf(s, "%ms %u", &sfamily, &group) < 1) return errno > 0 ? -errno : -EINVAL; family = netlink_family_from_string(sfamily); if (family < 0) return -EINVAL; a->sockaddr.nl.nl_family = AF_NETLINK; a->sockaddr.nl.nl_groups = group; a->type = SOCK_RAW; a->size = sizeof(struct sockaddr_nl); a->protocol = family; return 0; } int socket_address_verify(const SocketAddress *a) { assert(a); switch (socket_address_family(a)) { case AF_INET: if (a->size != sizeof(struct sockaddr_in)) return -EINVAL; if (a->sockaddr.in.sin_port == 0) return -EINVAL; if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM) return -EINVAL; return 0; case AF_INET6: if (a->size != sizeof(struct sockaddr_in6)) return -EINVAL; if (a->sockaddr.in6.sin6_port == 0) return -EINVAL; if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM) return -EINVAL; return 0; case AF_UNIX: if (a->size < offsetof(struct sockaddr_un, sun_path)) return -EINVAL; if (a->size > offsetof(struct sockaddr_un, sun_path)) { if (a->sockaddr.un.sun_path[0] != 0) { char *e; /* path */ e = memchr(a->sockaddr.un.sun_path, 0, sizeof(a->sockaddr.un.sun_path)); if (!e) return -EINVAL; if (a->size != offsetof(struct sockaddr_un, sun_path) + (e - a->sockaddr.un.sun_path) + 1) return -EINVAL; } } if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM && a->type != SOCK_SEQPACKET) return -EINVAL; return 0; case AF_NETLINK: if (a->size != sizeof(struct sockaddr_nl)) return -EINVAL; if (a->type != SOCK_RAW && a->type != SOCK_DGRAM) return -EINVAL; return 0; default: return -EAFNOSUPPORT; } } int socket_address_print(const SocketAddress *a, char **ret) { int r; assert(a); assert(ret); r = socket_address_verify(a); if (r < 0) return r; if (socket_address_family(a) == AF_NETLINK) { _cleanup_free_ char *sfamily = NULL; r = netlink_family_to_string_alloc(a->protocol, &sfamily); if (r < 0) return r; r = asprintf(ret, "%s %u", sfamily, a->sockaddr.nl.nl_groups); if (r < 0) return -ENOMEM; return 0; } return sockaddr_pretty(&a->sockaddr.sa, a->size, false, ret); } bool socket_address_can_accept(const SocketAddress *a) { assert(a); return a->type == SOCK_STREAM || a->type == SOCK_SEQPACKET; } bool socket_address_equal(const SocketAddress *a, const SocketAddress *b) { assert(a); assert(b); /* Invalid addresses are unequal to all */ if (socket_address_verify(a) < 0 || socket_address_verify(b) < 0) return false; if (a->type != b->type) return false; if (a->size != b->size) return false; if (socket_address_family(a) != socket_address_family(b)) return false; switch (socket_address_family(a)) { case AF_INET: if (a->sockaddr.in.sin_addr.s_addr != b->sockaddr.in.sin_addr.s_addr) return false; if (a->sockaddr.in.sin_port != b->sockaddr.in.sin_port) return false; break; case AF_INET6: if (memcmp(&a->sockaddr.in6.sin6_addr, &b->sockaddr.in6.sin6_addr, sizeof(a->sockaddr.in6.sin6_addr)) != 0) return false; if (a->sockaddr.in6.sin6_port != b->sockaddr.in6.sin6_port) return false; break; case AF_UNIX: if ((a->sockaddr.un.sun_path[0] == 0) != (b->sockaddr.un.sun_path[0] == 0)) return false; if (a->sockaddr.un.sun_path[0]) { if (!strneq(a->sockaddr.un.sun_path, b->sockaddr.un.sun_path, sizeof(a->sockaddr.un.sun_path))) return false; } else { if (memcmp(a->sockaddr.un.sun_path, b->sockaddr.un.sun_path, a->size) != 0) return false; } break; case AF_NETLINK: if (a->protocol != b->protocol) return false; if (a->sockaddr.nl.nl_groups != b->sockaddr.nl.nl_groups) return false; break; default: /* Cannot compare, so we assume the addresses are different */ return false; } return true; } bool socket_address_is(const SocketAddress *a, const char *s, int type) { struct SocketAddress b; assert(a); assert(s); if (socket_address_parse(&b, s) < 0) return false; b.type = type; return socket_address_equal(a, &b); } bool socket_address_is_netlink(const SocketAddress *a, const char *s) { struct SocketAddress b; assert(a); assert(s); if (socket_address_parse_netlink(&b, s) < 0) return false; return socket_address_equal(a, &b); } const char* socket_address_get_path(const SocketAddress *a) { assert(a); if (socket_address_family(a) != AF_UNIX) return NULL; if (a->sockaddr.un.sun_path[0] == 0) return NULL; return a->sockaddr.un.sun_path; } bool socket_ipv6_is_supported(void) { _cleanup_free_ char *l = NULL; if (access("/sys/module/ipv6", F_OK) != 0) return 0; /* If we can't check "disable" parameter, assume enabled */ if (read_one_line_file("/sys/module/ipv6/parameters/disable", &l) < 0) return 1; /* If module was loaded with disable=1 no IPv6 available */ return l[0] == '0'; } bool socket_address_matches_fd(const SocketAddress *a, int fd) { union sockaddr_union sa; socklen_t salen = sizeof(sa), solen; int protocol, type; assert(a); assert(fd >= 0); if (getsockname(fd, &sa.sa, &salen) < 0) return false; if (sa.sa.sa_family != a->sockaddr.sa.sa_family) return false; solen = sizeof(type); if (getsockopt(fd, SOL_SOCKET, SO_TYPE, &type, &solen) < 0) return false; if (type != a->type) return false; if (a->protocol != 0) { solen = sizeof(protocol); if (getsockopt(fd, SOL_SOCKET, SO_PROTOCOL, &protocol, &solen) < 0) return false; if (protocol != a->protocol) return false; } switch (sa.sa.sa_family) { case AF_INET: return sa.in.sin_port == a->sockaddr.in.sin_port && sa.in.sin_addr.s_addr == a->sockaddr.in.sin_addr.s_addr; case AF_INET6: return sa.in6.sin6_port == a->sockaddr.in6.sin6_port && memcmp(&sa.in6.sin6_addr, &a->sockaddr.in6.sin6_addr, sizeof(struct in6_addr)) == 0; case AF_UNIX: return salen == a->size && memcmp(sa.un.sun_path, a->sockaddr.un.sun_path, salen - offsetof(struct sockaddr_un, sun_path)) == 0; } return false; } int sockaddr_pretty(const struct sockaddr *_sa, socklen_t salen, bool translate_ipv6, char **ret) { union sockaddr_union *sa = (union sockaddr_union*) _sa; char *p; assert(sa); assert(salen >= sizeof(sa->sa.sa_family)); switch (sa->sa.sa_family) { case AF_INET: { uint32_t a; a = ntohl(sa->in.sin_addr.s_addr); if (asprintf(&p, "%u.%u.%u.%u:%u", a >> 24, (a >> 16) & 0xFF, (a >> 8) & 0xFF, a & 0xFF, ntohs(sa->in.sin_port)) < 0) return -ENOMEM; break; } case AF_INET6: { static const unsigned char ipv4_prefix[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF }; if (translate_ipv6 && memcmp(&sa->in6.sin6_addr, ipv4_prefix, sizeof(ipv4_prefix)) == 0) { const uint8_t *a = sa->in6.sin6_addr.s6_addr+12; if (asprintf(&p, "%u.%u.%u.%u:%u", a[0], a[1], a[2], a[3], ntohs(sa->in6.sin6_port)) < 0) return -ENOMEM; } else { char a[INET6_ADDRSTRLEN]; if (asprintf(&p, "[%s]:%u", inet_ntop(AF_INET6, &sa->in6.sin6_addr, a, sizeof(a)), ntohs(sa->in6.sin6_port)) < 0) return -ENOMEM; } break; } case AF_UNIX: if (salen <= offsetof(struct sockaddr_un, sun_path)) { p = strdup("<unnamed>"); if (!p) return -ENOMEM; } else if (sa->un.sun_path[0] == 0) { /* abstract */ /* FIXME: We assume we can print the * socket path here and that it hasn't * more than one NUL byte. That is * actually an invalid assumption */ p = new(char, sizeof(sa->un.sun_path)+1); if (!p) return -ENOMEM; p[0] = '@'; memcpy(p+1, sa->un.sun_path+1, sizeof(sa->un.sun_path)-1); p[sizeof(sa->un.sun_path)] = 0; } else { p = strndup(sa->un.sun_path, sizeof(sa->un.sun_path)); if (!ret) return -ENOMEM; } break; default: return -ENOTSUP; } *ret = p; return 0; } int getpeername_pretty(int fd, char **ret) { union sockaddr_union sa; socklen_t salen; int r; assert(fd >= 0); assert(ret); salen = sizeof(sa); if (getpeername(fd, &sa.sa, &salen) < 0) return -errno; if (sa.sa.sa_family == AF_UNIX) { struct ucred ucred = {}; /* UNIX connection sockets are anonymous, so let's use * PID/UID as pretty credentials instead */ r = getpeercred(fd, &ucred); if (r < 0) return r; if (asprintf(ret, "PID "PID_FMT"/UID "UID_FMT, ucred.pid, ucred.uid) < 0) return -ENOMEM; return 0; } /* For remote sockets we translate IPv6 addresses back to IPv4 * if applicable, since that's nicer. */ return sockaddr_pretty(&sa.sa, salen, true, ret); } int getsockname_pretty(int fd, char **ret) { union sockaddr_union sa; socklen_t salen; assert(fd >= 0); assert(ret); salen = sizeof(sa); if (getsockname(fd, &sa.sa, &salen) < 0) return -errno; /* For local sockets we do not translate IPv6 addresses back * to IPv6 if applicable, since this is usually used for * listening sockets where the difference between IPv4 and * IPv6 matters. */ return sockaddr_pretty(&sa.sa, salen, false, ret); } int socket_address_unlink(SocketAddress *a) { assert(a); if (socket_address_family(a) != AF_UNIX) return 0; if (a->sockaddr.un.sun_path[0] == 0) return 0; if (unlink(a->sockaddr.un.sun_path) < 0) return -errno; return 1; } static const char* const netlink_family_table[] = { [NETLINK_ROUTE] = "route", [NETLINK_FIREWALL] = "firewall", [NETLINK_INET_DIAG] = "inet-diag", [NETLINK_NFLOG] = "nflog", [NETLINK_XFRM] = "xfrm", [NETLINK_SELINUX] = "selinux", [NETLINK_ISCSI] = "iscsi", [NETLINK_AUDIT] = "audit", [NETLINK_FIB_LOOKUP] = "fib-lookup", [NETLINK_CONNECTOR] = "connector", [NETLINK_NETFILTER] = "netfilter", [NETLINK_IP6_FW] = "ip6-fw", [NETLINK_DNRTMSG] = "dnrtmsg", [NETLINK_KOBJECT_UEVENT] = "kobject-uevent", [NETLINK_GENERIC] = "generic", [NETLINK_SCSITRANSPORT] = "scsitransport", [NETLINK_ECRYPTFS] = "ecryptfs" }; DEFINE_STRING_TABLE_LOOKUP_WITH_FALLBACK(netlink_family, int, INT_MAX); static const char* const socket_address_bind_ipv6_only_table[_SOCKET_ADDRESS_BIND_IPV6_ONLY_MAX] = { [SOCKET_ADDRESS_DEFAULT] = "default", [SOCKET_ADDRESS_BOTH] = "both", [SOCKET_ADDRESS_IPV6_ONLY] = "ipv6-only" }; DEFINE_STRING_TABLE_LOOKUP(socket_address_bind_ipv6_only, SocketAddressBindIPv6Only);