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-rw-r--r--src/shared/socket-util.c652
1 files changed, 652 insertions, 0 deletions
diff --git a/src/shared/socket-util.c b/src/shared/socket-util.c
new file mode 100644
index 0000000000..acc4d33372
--- /dev/null
+++ b/src/shared/socket-util.c
@@ -0,0 +1,652 @@
+/*-*- 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 General Public License as published by
+ the Free Software Foundation; either version 2 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU 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 "socket-util.h"
+#include "missing.h"
+#include "label.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 */
+ if ((r = safe_atou(s, &u)) < 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;
+ 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;
+
+ if ((family = netlink_family_from_string(sfamily)) < 0)
+ if (safe_atoi(sfamily, &family) < 0) {
+ free(sfamily);
+ return -EINVAL;
+ }
+
+ free(sfamily);
+
+ 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: {
+ const char *sfamily;
+
+ if ((sfamily = netlink_family_to_string(a->protocol)))
+ r = asprintf(p, "%s %u", sfamily, a->sockaddr.nl.nl_groups);
+ else
+ r = asprintf(p, "%i %u", a->protocol, a->sockaddr.nl.nl_groups);
+
+ if (r < 0)
+ return -ENOMEM;
+
+ return 0;
+ }
+
+ default:
+ return -EINVAL;
+ }
+}
+
+int socket_address_listen(
+ const SocketAddress *a,
+ int backlog,
+ SocketAddressBindIPv6Only only,
+ const char *bind_to_device,
+ bool free_bind,
+ bool transparent,
+ mode_t directory_mode,
+ mode_t socket_mode,
+ const char *label,
+ int *ret) {
+
+ int r, fd, one;
+ assert(a);
+ assert(ret);
+
+ if ((r = socket_address_verify(a)) < 0)
+ return r;
+
+ if (socket_address_family(a) == AF_INET6 && !socket_ipv6_is_supported())
+ return -EAFNOSUPPORT;
+
+ r = label_socket_set(label);
+ if (r < 0)
+ return r;
+
+ fd = socket(socket_address_family(a), a->type | SOCK_NONBLOCK | SOCK_CLOEXEC, a->protocol);
+ r = fd < 0 ? -errno : 0;
+
+ label_socket_clear();
+
+ if (r < 0)
+ return r;
+
+ if (socket_address_family(a) == AF_INET6 && only != SOCKET_ADDRESS_DEFAULT) {
+ int flag = only == SOCKET_ADDRESS_IPV6_ONLY;
+
+ if (setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &flag, sizeof(flag)) < 0)
+ goto fail;
+ }
+
+ if (socket_address_family(a) == AF_INET || socket_address_family(a) == AF_INET6) {
+ if (bind_to_device)
+ if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, bind_to_device, strlen(bind_to_device)+1) < 0)
+ goto fail;
+
+ if (free_bind) {
+ one = 1;
+ if (setsockopt(fd, IPPROTO_IP, IP_FREEBIND, &one, sizeof(one)) < 0)
+ log_warning("IP_FREEBIND failed: %m");
+ }
+
+ if (transparent) {
+ one = 1;
+ if (setsockopt(fd, IPPROTO_IP, IP_TRANSPARENT, &one, sizeof(one)) < 0)
+ log_warning("IP_TRANSPARENT failed: %m");
+ }
+ }
+
+ one = 1;
+ if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)) < 0)
+ goto fail;
+
+ if (socket_address_family(a) == AF_UNIX && a->sockaddr.un.sun_path[0] != 0) {
+ mode_t old_mask;
+
+ /* Create parents */
+ mkdir_parents(a->sockaddr.un.sun_path, directory_mode);
+
+ /* Enforce the right access mode for the socket*/
+ old_mask = umask(~ socket_mode);
+
+ /* Include the original umask in our mask */
+ umask(~socket_mode | old_mask);
+
+ r = label_bind(fd, &a->sockaddr.sa, a->size);
+
+ if (r < 0 && errno == EADDRINUSE) {
+ /* Unlink and try again */
+ unlink(a->sockaddr.un.sun_path);
+ r = bind(fd, &a->sockaddr.sa, a->size);
+ }
+
+ umask(old_mask);
+ } else
+ r = bind(fd, &a->sockaddr.sa, a->size);
+
+ if (r < 0)
+ goto fail;
+
+ if (socket_address_can_accept(a))
+ if (listen(fd, backlog) < 0)
+ goto fail;
+
+ *ret = fd;
+ return 0;
+
+fail:
+ r = -errno;
+ close_nointr_nofail(fd);
+ return r;
+}
+
+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 (strncmp(a->sockaddr.un.sun_path, b->sockaddr.un.sun_path, sizeof(a->sockaddr.un.sun_path)) != 0)
+ 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;
+}
+
+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(netlink_family, int);
+
+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);
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-23 12:11:43 +0000