/*-*- 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) { int r; char *e, *n; unsigned u; 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; } if (!(e = strchr(s+1, ']'))) return -EINVAL; if (!(n = strndup(s+1, e-s-1))) return -ENOMEM; errno = 0; if (inet_pton(AF_INET6, n, &a->sockaddr.in6.sin6_addr) <= 0) { free(n); return errno != 0 ? -errno : -EINVAL; } free(n); e++; if (*e != ':') return -EINVAL; e++; if ((r = safe_atou(e, &u)) < 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 { if ((e = strchr(s, ':'))) { if ((r = safe_atou(e+1, &u)) < 0) return r; if (u <= 0 || u > 0xFFFF) return -EINVAL; if (!(n = strndup(s, e-s))) return -ENOMEM; /* IPv4 in w.x.y.z:p notation? */ if ((r = inet_pton(AF_INET, n, &a->sockaddr.in4.sin_addr)) < 0) { free(n); return -errno; } if (r > 0) { /* Gotcha, it's a traditional IPv4 address */ free(n); a->sockaddr.in4.sin_family = AF_INET; a->sockaddr.in4.sin_port = htons((uint16_t) u); a->size = sizeof(struct sockaddr_in); } else { unsigned idx; if (strlen(n) > IF_NAMESIZE-1) { free(n); return -EINVAL; } /* Uh, our last resort, an interface name */ idx = if_nametoindex(n); free(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.in4.sin_family = AF_INET; a->sockaddr.in4.sin_port = htons((uint16_t) u); a->sockaddr.in4.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 ? -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.in4.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 */ if (!(e = memchr(a->sockaddr.un.sun_path, 0, sizeof(a->sockaddr.un.sun_path)))) 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 **p) { int r; assert(a); assert(p); if ((r = socket_address_verify(a)) < 0) return r; switch (socket_address_family(a)) { case AF_INET: { char *ret; if (!(ret = new(char, INET_ADDRSTRLEN+1+5+1))) return -ENOMEM; if (!inet_ntop(AF_INET, &a->sockaddr.in4.sin_addr, ret, INET_ADDRSTRLEN)) { free(ret); return -errno; } sprintf(strchr(ret, 0), ":%u", ntohs(a->sockaddr.in4.sin_port)); *p = ret; return 0; } case AF_INET6: { char *ret; if (!(ret = new(char, 1+INET6_ADDRSTRLEN+2+5+1))) return -ENOMEM; ret[0] = '['; if (!inet_ntop(AF_INET6, &a->sockaddr.in6.sin6_addr, ret+1, INET6_ADDRSTRLEN)) { free(ret); return -errno; } sprintf(strchr(ret, 0), "]:%u", ntohs(a->sockaddr.in6.sin6_port)); *p = ret; return 0; } case AF_UNIX: { char *ret; if (a->size <= offsetof(struct sockaddr_un, sun_path)) { if (!(ret = strdup("<unnamed>"))) return -ENOMEM; } else if (a->sockaddr.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 */ if (!(ret = new(char, sizeof(a->sockaddr.un.sun_path)+1))) return -ENOMEM; ret[0] = '@'; memcpy(ret+1, a->sockaddr.un.sun_path+1, sizeof(a->sockaddr.un.sun_path)-1); ret[sizeof(a->sockaddr.un.sun_path)] = 0; } else { if (!(ret = strdup(a->sockaddr.un.sun_path))) return -ENOMEM; } *p = ret; return 0; } case AF_NETLINK: { char _cleanup_free_ *sfamily = NULL; r = netlink_family_to_string_alloc(a->protocol, &sfamily); if (r < 0) return r; r = asprintf(p, "%s %u", sfamily, a->sockaddr.nl.nl_groups); if (r < 0) return -ENOMEM; return 0; } default: return -EINVAL; } } 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.in4.sin_addr.s_addr != b->sockaddr.in4.sin_addr.s_addr) return false; if (a->sockaddr.in4.sin_port != b->sockaddr.in4.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); } bool socket_address_needs_mount(const SocketAddress *a, const char *prefix) { assert(a); if (socket_address_family(a) != AF_UNIX) return false; if (a->sockaddr.un.sun_path[0] == 0) return false; return path_startswith(a->sockaddr.un.sun_path, prefix); } bool socket_ipv6_is_supported(void) { char *l = 0; bool enabled; 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 */ enabled = l[0] == '0'; free(l); return enabled; } 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.in4.sin_port == a->sockaddr.in4.sin_port && sa.in4.sin_addr.s_addr == a->sockaddr.in4.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 make_socket_fd(const char* address, int flags) { SocketAddress a; int fd, r; char _cleanup_free_ *p = NULL; r = socket_address_parse(&a, address); if (r < 0) { log_error("failed to parse socket: %s", strerror(-r)); return r; } fd = socket(socket_address_family(&a), flags, 0); if (fd < 0) { log_error("socket(): %m"); return -errno; } r = socket_address_print(&a, &p); if (r < 0) { log_error("socket_address_print(): %s", strerror(-r)); return r; } log_info("Listening on %s", p); r = bind(fd, &a.sockaddr.sa, a.size); if (r < 0) { log_error("bind to %s: %m", address); return -errno; } r = listen(fd, SOMAXCONN); if (r < 0) { log_error("listen on %s: %m", address); return -errno; } return fd; } 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);