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-rw-r--r--src/basic/socket-util.c1696
1 files changed, 1696 insertions, 0 deletions
diff --git a/src/basic/socket-util.c b/src/basic/socket-util.c
new file mode 100644
index 0000000..beb64d8
--- /dev/null
+++ b/src/basic/socket-util.c
@@ -0,0 +1,1696 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <arpa/inet.h>
+#include <errno.h>
+#include <limits.h>
+#include <net/if.h>
+#include <netdb.h>
+#include <netinet/ip.h>
+#include <poll.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+#include <linux/if.h>
+
+#include "alloc-util.h"
+#include "errno-util.h"
+#include "escape.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "format-util.h"
+#include "io-util.h"
+#include "log.h"
+#include "memory-util.h"
+#include "parse-util.h"
+#include "path-util.h"
+#include "process-util.h"
+#include "socket-util.h"
+#include "string-table.h"
+#include "string-util.h"
+#include "strv.h"
+#include "sysctl-util.h"
+#include "user-util.h"
+#include "utf8.h"
+
+#if ENABLE_IDN
+# define IDN_FLAGS NI_IDN
+#else
+# define IDN_FLAGS 0
+#endif
+
+/* From the kernel's include/net/scm.h */
+#ifndef SCM_MAX_FD
+# define SCM_MAX_FD 253
+#endif
+
+static const char* const socket_address_type_table[] = {
+ [SOCK_STREAM] = "Stream",
+ [SOCK_DGRAM] = "Datagram",
+ [SOCK_RAW] = "Raw",
+ [SOCK_RDM] = "ReliableDatagram",
+ [SOCK_SEQPACKET] = "SequentialPacket",
+ [SOCK_DCCP] = "DatagramCongestionControl",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(socket_address_type, int);
+
+int socket_address_verify(const SocketAddress *a, bool strict) {
+ assert(a);
+
+ /* With 'strict' we enforce additional sanity constraints which are not set by the standard,
+ * but should only apply to sockets we create ourselves. */
+
+ 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 (!IN_SET(a->type, 0, SOCK_STREAM, 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 (!IN_SET(a->type, 0, SOCK_STREAM, SOCK_DGRAM))
+ return -EINVAL;
+
+ return 0;
+
+ case AF_UNIX:
+ if (a->size < offsetof(struct sockaddr_un, sun_path))
+ return -EINVAL;
+ if (a->size > sizeof(struct sockaddr_un) + !strict)
+ /* If !strict, allow one extra byte, since getsockname() on Linux will append
+ * a NUL byte if we have path sockets that are above sun_path's full size. */
+ return -EINVAL;
+
+ if (a->size > offsetof(struct sockaddr_un, sun_path) &&
+ a->sockaddr.un.sun_path[0] != 0 &&
+ strict) {
+ /* Only validate file system sockets here, and only in strict mode */
+ const char *e;
+
+ e = memchr(a->sockaddr.un.sun_path, 0, sizeof(a->sockaddr.un.sun_path));
+ if (e) {
+ /* If there's an embedded NUL byte, make sure the size of the socket address matches it */
+ if (a->size != offsetof(struct sockaddr_un, sun_path) + (e - a->sockaddr.un.sun_path) + 1)
+ return -EINVAL;
+ } else {
+ /* If there's no embedded NUL byte, then the size needs to match the whole
+ * structure or the structure with one extra NUL byte suffixed. (Yeah, Linux is awful,
+ * and considers both equivalent: getsockname() even extends sockaddr_un beyond its
+ * size if the path is non NUL terminated.) */
+ if (!IN_SET(a->size, sizeof(a->sockaddr.un.sun_path), sizeof(a->sockaddr.un.sun_path)+1))
+ return -EINVAL;
+ }
+ }
+
+ if (!IN_SET(a->type, 0, SOCK_STREAM, SOCK_DGRAM, SOCK_SEQPACKET))
+ return -EINVAL;
+
+ return 0;
+
+ case AF_NETLINK:
+
+ if (a->size != sizeof(struct sockaddr_nl))
+ return -EINVAL;
+
+ if (!IN_SET(a->type, 0, SOCK_RAW, SOCK_DGRAM))
+ return -EINVAL;
+
+ return 0;
+
+ case AF_VSOCK:
+ if (a->size != sizeof(struct sockaddr_vm))
+ return -EINVAL;
+
+ if (!IN_SET(a->type, 0, SOCK_STREAM, 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, false); /* We do non-strict validation, because we want to be
+ * able to pretty-print any socket the kernel considers
+ * valid. We still need to do validation to know if we
+ * can meaningfully print the address. */
+ 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, true, ret);
+}
+
+bool socket_address_can_accept(const SocketAddress *a) {
+ assert(a);
+
+ return
+ IN_SET(a->type, SOCK_STREAM, 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, false) < 0 ||
+ socket_address_verify(b, false) < 0)
+ return false;
+
+ if (a->type != b->type)
+ 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->size <= offsetof(struct sockaddr_un, sun_path) ||
+ b->size <= offsetof(struct sockaddr_un, sun_path))
+ return false;
+
+ 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 (!path_equal_or_inode_same(a->sockaddr.un.sun_path, b->sockaddr.un.sun_path, 0))
+ return false;
+ } else {
+ if (a->size != b->size)
+ return false;
+
+ 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;
+
+ case AF_VSOCK:
+ if (a->sockaddr.vm.svm_cid != b->sockaddr.vm.svm_cid)
+ return false;
+
+ if (a->sockaddr.vm.svm_port != b->sockaddr.vm.svm_port)
+ return false;
+
+ break;
+
+ default:
+ /* Cannot compare, so we assume the addresses are different */
+ return false;
+ }
+
+ return true;
+}
+
+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;
+
+ /* Note that this is only safe because we know that there's an extra NUL byte after the sockaddr_un
+ * structure. On Linux AF_UNIX file system socket addresses don't have to be NUL terminated if they take up the
+ * full sun_path space. */
+ assert_cc(sizeof(union sockaddr_union) >= sizeof(struct sockaddr_un)+1);
+ return a->sockaddr.un.sun_path;
+}
+
+bool socket_ipv6_is_supported(void) {
+ static int cached = -1;
+
+ if (cached < 0) {
+
+ if (access("/proc/net/if_inet6", F_OK) < 0) {
+
+ if (errno != ENOENT) {
+ log_debug_errno(errno, "Unexpected error when checking whether /proc/net/if_inet6 exists: %m");
+ return false;
+ }
+
+ cached = false;
+ } else
+ cached = true;
+ }
+
+ return cached;
+}
+
+bool socket_ipv6_is_enabled(void) {
+ _cleanup_free_ char *v = NULL;
+ int r;
+
+ /* Much like socket_ipv6_is_supported(), but also checks that the sysctl that disables IPv6 on all
+ * interfaces isn't turned on */
+
+ if (!socket_ipv6_is_supported())
+ return false;
+
+ r = sysctl_read_ip_property(AF_INET6, "all", "disable_ipv6", &v);
+ if (r < 0) {
+ log_debug_errno(r, "Unexpected error reading 'net.ipv6.conf.all.disable_ipv6' sysctl: %m");
+ return true;
+ }
+
+ r = parse_boolean(v);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to pare 'net.ipv6.conf.all.disable_ipv6' sysctl: %m");
+ return true;
+ }
+
+ return !r;
+}
+
+bool socket_address_matches_fd(const SocketAddress *a, int fd) {
+ SocketAddress b;
+ socklen_t solen;
+
+ assert(a);
+ assert(fd >= 0);
+
+ b.size = sizeof(b.sockaddr);
+ if (getsockname(fd, &b.sockaddr.sa, &b.size) < 0)
+ return false;
+
+ if (b.sockaddr.sa.sa_family != a->sockaddr.sa.sa_family)
+ return false;
+
+ solen = sizeof(b.type);
+ if (getsockopt(fd, SOL_SOCKET, SO_TYPE, &b.type, &solen) < 0)
+ return false;
+
+ if (b.type != a->type)
+ return false;
+
+ if (a->protocol != 0) {
+ solen = sizeof(b.protocol);
+ if (getsockopt(fd, SOL_SOCKET, SO_PROTOCOL, &b.protocol, &solen) < 0)
+ return false;
+
+ if (b.protocol != a->protocol)
+ return false;
+ }
+
+ return socket_address_equal(a, &b);
+}
+
+int sockaddr_port(const struct sockaddr *_sa, unsigned *ret_port) {
+ const union sockaddr_union *sa = (const union sockaddr_union*) _sa;
+
+ /* Note, this returns the port as 'unsigned' rather than 'uint16_t', as AF_VSOCK knows larger ports */
+
+ assert(sa);
+
+ switch (sa->sa.sa_family) {
+
+ case AF_INET:
+ *ret_port = be16toh(sa->in.sin_port);
+ return 0;
+
+ case AF_INET6:
+ *ret_port = be16toh(sa->in6.sin6_port);
+ return 0;
+
+ case AF_VSOCK:
+ *ret_port = sa->vm.svm_port;
+ return 0;
+
+ default:
+ return -EAFNOSUPPORT;
+ }
+}
+
+const union in_addr_union *sockaddr_in_addr(const struct sockaddr *_sa) {
+ const union sockaddr_union *sa = (const union sockaddr_union*) _sa;
+
+ if (!sa)
+ return NULL;
+
+ switch (sa->sa.sa_family) {
+
+ case AF_INET:
+ return (const union in_addr_union*) &sa->in.sin_addr;
+
+ case AF_INET6:
+ return (const union in_addr_union*) &sa->in6.sin6_addr;
+
+ default:
+ return NULL;
+ }
+}
+
+int sockaddr_set_in_addr(
+ union sockaddr_union *u,
+ int family,
+ const union in_addr_union *a,
+ uint16_t port) {
+
+ assert(u);
+ assert(a);
+
+ switch (family) {
+
+ case AF_INET:
+ u->in = (struct sockaddr_in) {
+ .sin_family = AF_INET,
+ .sin_addr = a->in,
+ .sin_port = htobe16(port),
+ };
+
+ return 0;
+
+ case AF_INET6:
+ u->in6 = (struct sockaddr_in6) {
+ .sin6_family = AF_INET6,
+ .sin6_addr = a->in6,
+ .sin6_port = htobe16(port),
+ };
+
+ return 0;
+
+ default:
+ return -EAFNOSUPPORT;
+
+ }
+}
+
+int sockaddr_pretty(
+ const struct sockaddr *_sa,
+ socklen_t salen,
+ bool translate_ipv6,
+ bool include_port,
+ char **ret) {
+
+ union sockaddr_union *sa = (union sockaddr_union*) _sa;
+ char *p;
+ int r;
+
+ assert(sa);
+ assert(salen >= sizeof(sa->sa.sa_family));
+
+ switch (sa->sa.sa_family) {
+
+ case AF_INET: {
+ uint32_t a;
+
+ a = be32toh(sa->in.sin_addr.s_addr);
+
+ if (include_port)
+ r = asprintf(&p,
+ "%u.%u.%u.%u:%u",
+ a >> 24, (a >> 16) & 0xFF, (a >> 8) & 0xFF, a & 0xFF,
+ be16toh(sa->in.sin_port));
+ else
+ r = asprintf(&p,
+ "%u.%u.%u.%u",
+ a >> 24, (a >> 16) & 0xFF, (a >> 8) & 0xFF, a & 0xFF);
+ if (r < 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 (include_port)
+ r = asprintf(&p,
+ "%u.%u.%u.%u:%u",
+ a[0], a[1], a[2], a[3],
+ be16toh(sa->in6.sin6_port));
+ else
+ r = asprintf(&p,
+ "%u.%u.%u.%u",
+ a[0], a[1], a[2], a[3]);
+ if (r < 0)
+ return -ENOMEM;
+ } else {
+ const char *a = IN6_ADDR_TO_STRING(&sa->in6.sin6_addr);
+
+ if (include_port) {
+ if (asprintf(&p,
+ "[%s]:%u%s%s",
+ a,
+ be16toh(sa->in6.sin6_port),
+ sa->in6.sin6_scope_id != 0 ? "%" : "",
+ FORMAT_IFNAME_FULL(sa->in6.sin6_scope_id, FORMAT_IFNAME_IFINDEX)) < 0)
+ return -ENOMEM;
+ } else {
+ if (sa->in6.sin6_scope_id != 0)
+ p = strjoin(a, "%", FORMAT_IFNAME_FULL(sa->in6.sin6_scope_id, FORMAT_IFNAME_IFINDEX));
+ else
+ p = strdup(a);
+ if (!p)
+ return -ENOMEM;
+ }
+ }
+
+ break;
+ }
+
+ case AF_UNIX:
+ if (salen <= offsetof(struct sockaddr_un, sun_path) ||
+ (sa->un.sun_path[0] == 0 && salen == offsetof(struct sockaddr_un, sun_path) + 1))
+ /* The name must have at least one character (and the leading NUL does not count) */
+ p = strdup("<unnamed>");
+ else {
+ /* Note that we calculate the path pointer here through the .un_buffer[] field, in order to
+ * outtrick bounds checking tools such as ubsan, which are too smart for their own good: on
+ * Linux the kernel may return sun_path[] data one byte longer than the declared size of the
+ * field. */
+ char *path = (char*) sa->un_buffer + offsetof(struct sockaddr_un, sun_path);
+ size_t path_len = salen - offsetof(struct sockaddr_un, sun_path);
+
+ if (path[0] == 0) {
+ /* Abstract socket. When parsing address information from, we
+ * explicitly reject overly long paths and paths with embedded NULs.
+ * But we might get such a socket from the outside. Let's return
+ * something meaningful and printable in this case. */
+
+ _cleanup_free_ char *e = NULL;
+
+ e = cescape_length(path + 1, path_len - 1);
+ if (!e)
+ return -ENOMEM;
+
+ p = strjoin("@", e);
+ } else {
+ if (path[path_len - 1] == '\0')
+ /* We expect a terminating NUL and don't print it */
+ path_len --;
+
+ p = cescape_length(path, path_len);
+ }
+ }
+ if (!p)
+ return -ENOMEM;
+
+ break;
+
+ case AF_VSOCK:
+ if (include_port) {
+ if (sa->vm.svm_cid == VMADDR_CID_ANY)
+ r = asprintf(&p, "vsock::%u", sa->vm.svm_port);
+ else
+ r = asprintf(&p, "vsock:%u:%u", sa->vm.svm_cid, sa->vm.svm_port);
+ } else
+ r = asprintf(&p, "vsock:%u", sa->vm.svm_cid);
+ if (r < 0)
+ return -ENOMEM;
+ break;
+
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ *ret = p;
+ return 0;
+}
+
+int getpeername_pretty(int fd, bool include_port, char **ret) {
+ union sockaddr_union sa;
+ socklen_t salen = sizeof(sa);
+ int r;
+
+ assert(fd >= 0);
+ assert(ret);
+
+ if (getpeername(fd, &sa.sa, &salen) < 0)
+ return -errno;
+
+ if (sa.sa.sa_family == AF_UNIX) {
+ struct ucred ucred = UCRED_INVALID;
+
+ /* 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, include_port, ret);
+}
+
+int getsockname_pretty(int fd, char **ret) {
+ union sockaddr_union sa;
+ socklen_t salen = sizeof(sa);
+
+ assert(fd >= 0);
+ assert(ret);
+
+ 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, true, ret);
+}
+
+int socknameinfo_pretty(union sockaddr_union *sa, socklen_t salen, char **_ret) {
+ int r;
+ char host[NI_MAXHOST], *ret;
+
+ assert(_ret);
+
+ r = getnameinfo(&sa->sa, salen, host, sizeof(host), NULL, 0, IDN_FLAGS);
+ if (r != 0) {
+ int saved_errno = errno;
+
+ r = sockaddr_pretty(&sa->sa, salen, true, true, &ret);
+ if (r < 0)
+ return r;
+
+ log_debug_errno(saved_errno, "getnameinfo(%s) failed: %m", ret);
+ } else {
+ ret = strdup(host);
+ if (!ret)
+ return -ENOMEM;
+ }
+
+ *_ret = ret;
+ return 0;
+}
+
+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",
+ [NETLINK_RDMA] = "rdma",
+};
+
+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);
+
+SocketAddressBindIPv6Only socket_address_bind_ipv6_only_or_bool_from_string(const char *n) {
+ int r;
+
+ r = parse_boolean(n);
+ if (r > 0)
+ return SOCKET_ADDRESS_IPV6_ONLY;
+ if (r == 0)
+ return SOCKET_ADDRESS_BOTH;
+
+ return socket_address_bind_ipv6_only_from_string(n);
+}
+
+bool sockaddr_equal(const union sockaddr_union *a, const union sockaddr_union *b) {
+ assert(a);
+ assert(b);
+
+ if (a->sa.sa_family != b->sa.sa_family)
+ return false;
+
+ if (a->sa.sa_family == AF_INET)
+ return a->in.sin_addr.s_addr == b->in.sin_addr.s_addr;
+
+ if (a->sa.sa_family == AF_INET6)
+ return memcmp(&a->in6.sin6_addr, &b->in6.sin6_addr, sizeof(a->in6.sin6_addr)) == 0;
+
+ if (a->sa.sa_family == AF_VSOCK)
+ return a->vm.svm_cid == b->vm.svm_cid;
+
+ return false;
+}
+
+int fd_set_sndbuf(int fd, size_t n, bool increase) {
+ int r, value;
+ socklen_t l = sizeof(value);
+
+ if (n > INT_MAX)
+ return -ERANGE;
+
+ r = getsockopt(fd, SOL_SOCKET, SO_SNDBUF, &value, &l);
+ if (r >= 0 && l == sizeof(value) && increase ? (size_t) value >= n*2 : (size_t) value == n*2)
+ return 0;
+
+ /* First, try to set the buffer size with SO_SNDBUF. */
+ r = setsockopt_int(fd, SOL_SOCKET, SO_SNDBUF, n);
+ if (r < 0)
+ return r;
+
+ /* SO_SNDBUF above may set to the kernel limit, instead of the requested size.
+ * So, we need to check the actual buffer size here. */
+ l = sizeof(value);
+ r = getsockopt(fd, SOL_SOCKET, SO_SNDBUF, &value, &l);
+ if (r >= 0 && l == sizeof(value) && increase ? (size_t) value >= n*2 : (size_t) value == n*2)
+ return 1;
+
+ /* If we have the privileges we will ignore the kernel limit. */
+ r = setsockopt_int(fd, SOL_SOCKET, SO_SNDBUFFORCE, n);
+ if (r < 0)
+ return r;
+
+ return 1;
+}
+
+int fd_set_rcvbuf(int fd, size_t n, bool increase) {
+ int r, value;
+ socklen_t l = sizeof(value);
+
+ if (n > INT_MAX)
+ return -ERANGE;
+
+ r = getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &value, &l);
+ if (r >= 0 && l == sizeof(value) && increase ? (size_t) value >= n*2 : (size_t) value == n*2)
+ return 0;
+
+ /* First, try to set the buffer size with SO_RCVBUF. */
+ r = setsockopt_int(fd, SOL_SOCKET, SO_RCVBUF, n);
+ if (r < 0)
+ return r;
+
+ /* SO_RCVBUF above may set to the kernel limit, instead of the requested size.
+ * So, we need to check the actual buffer size here. */
+ l = sizeof(value);
+ r = getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &value, &l);
+ if (r >= 0 && l == sizeof(value) && increase ? (size_t) value >= n*2 : (size_t) value == n*2)
+ return 1;
+
+ /* If we have the privileges we will ignore the kernel limit. */
+ r = setsockopt_int(fd, SOL_SOCKET, SO_RCVBUFFORCE, n);
+ if (r < 0)
+ return r;
+
+ return 1;
+}
+
+static const char* const ip_tos_table[] = {
+ [IPTOS_LOWDELAY] = "low-delay",
+ [IPTOS_THROUGHPUT] = "throughput",
+ [IPTOS_RELIABILITY] = "reliability",
+ [IPTOS_LOWCOST] = "low-cost",
+};
+
+DEFINE_STRING_TABLE_LOOKUP_WITH_FALLBACK(ip_tos, int, 0xff);
+
+bool ifname_valid_char(char a) {
+ if ((unsigned char) a >= 127U)
+ return false;
+
+ if ((unsigned char) a <= 32U)
+ return false;
+
+ if (IN_SET(a,
+ ':', /* colons are used by the legacy "alias" interface logic */
+ '/', /* slashes cannot work, since we need to use network interfaces in sysfs paths, and in paths slashes are separators */
+ '%')) /* %d is used in the kernel's weird foo%d format string naming feature which we really really don't want to ever run into by accident */
+ return false;
+
+ return true;
+}
+
+bool ifname_valid_full(const char *p, IfnameValidFlags flags) {
+ bool numeric = true;
+
+ /* Checks whether a network interface name is valid. This is inspired by dev_valid_name() in the kernel sources
+ * but slightly stricter, as we only allow non-control, non-space ASCII characters in the interface name. We
+ * also don't permit names that only container numbers, to avoid confusion with numeric interface indexes. */
+
+ assert(!(flags & ~_IFNAME_VALID_ALL));
+
+ if (isempty(p))
+ return false;
+
+ /* A valid ifindex? If so, it's valid iff IFNAME_VALID_NUMERIC is set */
+ if (parse_ifindex(p) >= 0)
+ return flags & IFNAME_VALID_NUMERIC;
+
+ if (flags & IFNAME_VALID_ALTERNATIVE) {
+ if (strlen(p) >= ALTIFNAMSIZ)
+ return false;
+ } else {
+ if (strlen(p) >= IFNAMSIZ)
+ return false;
+ }
+
+ if (dot_or_dot_dot(p))
+ return false;
+
+ /* Let's refuse "all" and "default" as interface name, to avoid collisions with the special sysctl
+ * directories /proc/sys/net/{ipv4,ipv6}/conf/{all,default} */
+ if (!FLAGS_SET(flags, IFNAME_VALID_SPECIAL) && STR_IN_SET(p, "all", "default"))
+ return false;
+
+ for (const char *t = p; *t; t++) {
+ if (!ifname_valid_char(*t))
+ return false;
+
+ numeric = numeric && ascii_isdigit(*t);
+ }
+
+ /* It's fully numeric but didn't parse as valid ifindex above? if so, it must be too large or zero or
+ * so, let's refuse that. */
+ if (numeric)
+ return false;
+
+ return true;
+}
+
+bool address_label_valid(const char *p) {
+
+ if (isempty(p))
+ return false;
+
+ if (strlen(p) >= IFNAMSIZ)
+ return false;
+
+ while (*p) {
+ if ((uint8_t) *p >= 127U)
+ return false;
+
+ if ((uint8_t) *p <= 31U)
+ return false;
+ p++;
+ }
+
+ return true;
+}
+
+int getpeercred(int fd, struct ucred *ucred) {
+ socklen_t n = sizeof(struct ucred);
+ struct ucred u;
+ int r;
+
+ assert(fd >= 0);
+ assert(ucred);
+
+ r = getsockopt(fd, SOL_SOCKET, SO_PEERCRED, &u, &n);
+ if (r < 0)
+ return -errno;
+
+ if (n != sizeof(struct ucred))
+ return -EIO;
+
+ /* Check if the data is actually useful and not suppressed due to namespacing issues */
+ if (!pid_is_valid(u.pid))
+ return -ENODATA;
+
+ /* Note that we don't check UID/GID here, as namespace translation works differently there: instead of
+ * receiving in "invalid" user/group we get the overflow UID/GID. */
+
+ *ucred = u;
+ return 0;
+}
+
+int getpeersec(int fd, char **ret) {
+ _cleanup_free_ char *s = NULL;
+ socklen_t n = 64;
+
+ assert(fd >= 0);
+ assert(ret);
+
+ for (;;) {
+ s = new0(char, n+1);
+ if (!s)
+ return -ENOMEM;
+
+ if (getsockopt(fd, SOL_SOCKET, SO_PEERSEC, s, &n) >= 0)
+ break;
+
+ if (errno != ERANGE)
+ return -errno;
+
+ s = mfree(s);
+ }
+
+ if (isempty(s))
+ return -EOPNOTSUPP;
+
+ *ret = TAKE_PTR(s);
+
+ return 0;
+}
+
+int getpeergroups(int fd, gid_t **ret) {
+ socklen_t n = sizeof(gid_t) * 64;
+ _cleanup_free_ gid_t *d = NULL;
+
+ assert(fd >= 0);
+ assert(ret);
+
+ for (;;) {
+ d = malloc(n);
+ if (!d)
+ return -ENOMEM;
+
+ if (getsockopt(fd, SOL_SOCKET, SO_PEERGROUPS, d, &n) >= 0)
+ break;
+
+ if (errno != ERANGE)
+ return -errno;
+
+ d = mfree(d);
+ }
+
+ assert_se(n % sizeof(gid_t) == 0);
+ n /= sizeof(gid_t);
+
+ if ((socklen_t) (int) n != n)
+ return -E2BIG;
+
+ *ret = TAKE_PTR(d);
+
+ return (int) n;
+}
+
+ssize_t send_many_fds_iov_sa(
+ int transport_fd,
+ int *fds_array, size_t n_fds_array,
+ const struct iovec *iov, size_t iovlen,
+ const struct sockaddr *sa, socklen_t len,
+ int flags) {
+
+ _cleanup_free_ struct cmsghdr *cmsg = NULL;
+ struct msghdr mh = {
+ .msg_name = (struct sockaddr*) sa,
+ .msg_namelen = len,
+ .msg_iov = (struct iovec *)iov,
+ .msg_iovlen = iovlen,
+ };
+ ssize_t k;
+
+ assert(transport_fd >= 0);
+ assert(fds_array || n_fds_array == 0);
+
+ /* The kernel will reject sending more than SCM_MAX_FD FDs at once */
+ if (n_fds_array > SCM_MAX_FD)
+ return -E2BIG;
+
+ /* We need either an FD array or data to send. If there's nothing, return an error. */
+ if (n_fds_array == 0 && !iov)
+ return -EINVAL;
+
+ if (n_fds_array > 0) {
+ mh.msg_controllen = CMSG_SPACE(sizeof(int) * n_fds_array);
+ mh.msg_control = cmsg = malloc(mh.msg_controllen);
+ if (!cmsg)
+ return -ENOMEM;
+
+ *cmsg = (struct cmsghdr) {
+ .cmsg_len = CMSG_LEN(sizeof(int) * n_fds_array),
+ .cmsg_level = SOL_SOCKET,
+ .cmsg_type = SCM_RIGHTS,
+ };
+ memcpy(CMSG_DATA(cmsg), fds_array, sizeof(int) * n_fds_array);
+ }
+ k = sendmsg(transport_fd, &mh, MSG_NOSIGNAL | flags);
+ if (k < 0)
+ return (ssize_t) -errno;
+
+ return k;
+}
+
+ssize_t send_one_fd_iov_sa(
+ int transport_fd,
+ int fd,
+ const struct iovec *iov, size_t iovlen,
+ const struct sockaddr *sa, socklen_t len,
+ int flags) {
+
+ CMSG_BUFFER_TYPE(CMSG_SPACE(sizeof(int))) control = {};
+ struct msghdr mh = {
+ .msg_name = (struct sockaddr*) sa,
+ .msg_namelen = len,
+ .msg_iov = (struct iovec *)iov,
+ .msg_iovlen = iovlen,
+ };
+ ssize_t k;
+
+ assert(transport_fd >= 0);
+
+ /*
+ * We need either an FD or data to send.
+ * If there's nothing, return an error.
+ */
+ if (fd < 0 && !iov)
+ return -EINVAL;
+
+ if (fd >= 0) {
+ struct cmsghdr *cmsg;
+
+ mh.msg_control = &control;
+ mh.msg_controllen = sizeof(control);
+
+ cmsg = CMSG_FIRSTHDR(&mh);
+ cmsg->cmsg_level = SOL_SOCKET;
+ cmsg->cmsg_type = SCM_RIGHTS;
+ cmsg->cmsg_len = CMSG_LEN(sizeof(int));
+ memcpy(CMSG_DATA(cmsg), &fd, sizeof(int));
+ }
+ k = sendmsg(transport_fd, &mh, MSG_NOSIGNAL | flags);
+ if (k < 0)
+ return (ssize_t) -errno;
+
+ return k;
+}
+
+int send_one_fd_sa(
+ int transport_fd,
+ int fd,
+ const struct sockaddr *sa, socklen_t len,
+ int flags) {
+
+ assert(fd >= 0);
+
+ return (int) send_one_fd_iov_sa(transport_fd, fd, NULL, 0, sa, len, flags);
+}
+
+ssize_t receive_many_fds_iov(
+ int transport_fd,
+ struct iovec *iov, size_t iovlen,
+ int **ret_fds_array, size_t *ret_n_fds_array,
+ int flags) {
+
+ CMSG_BUFFER_TYPE(CMSG_SPACE(sizeof(int) * SCM_MAX_FD)) control;
+ struct msghdr mh = {
+ .msg_control = &control,
+ .msg_controllen = sizeof(control),
+ .msg_iov = iov,
+ .msg_iovlen = iovlen,
+ };
+ _cleanup_free_ int *fds_array = NULL;
+ size_t n_fds_array = 0;
+ struct cmsghdr *cmsg;
+ ssize_t k;
+
+ assert(transport_fd >= 0);
+ assert(ret_fds_array);
+ assert(ret_n_fds_array);
+
+ /*
+ * Receive many FDs via @transport_fd. We don't care for the transport-type. We retrieve all the FDs
+ * at once. This is best used in combination with send_many_fds().
+ */
+
+ k = recvmsg_safe(transport_fd, &mh, MSG_CMSG_CLOEXEC | flags);
+ if (k < 0)
+ return k;
+
+ CMSG_FOREACH(cmsg, &mh)
+ if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) {
+ size_t n = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int);
+
+ fds_array = GREEDY_REALLOC(fds_array, n_fds_array + n);
+ if (!fds_array) {
+ cmsg_close_all(&mh);
+ return -ENOMEM;
+ }
+
+ memcpy(fds_array + n_fds_array, CMSG_TYPED_DATA(cmsg, int), sizeof(int) * n);
+ n_fds_array += n;
+ }
+
+ if (n_fds_array == 0) {
+ cmsg_close_all(&mh);
+
+ /* If didn't receive an FD or any data, return an error. */
+ if (k == 0)
+ return -EIO;
+ }
+
+ *ret_fds_array = TAKE_PTR(fds_array);
+ *ret_n_fds_array = n_fds_array;
+
+ return k;
+}
+
+int receive_many_fds(int transport_fd, int **ret_fds_array, size_t *ret_n_fds_array, int flags) {
+ ssize_t k;
+
+ k = receive_many_fds_iov(transport_fd, NULL, 0, ret_fds_array, ret_n_fds_array, flags);
+ if (k == 0)
+ return 0;
+
+ /* k must be negative, since receive_many_fds_iov() only returns a positive value if data was received
+ * through the iov. */
+ assert(k < 0);
+ return (int) k;
+}
+
+ssize_t receive_one_fd_iov(
+ int transport_fd,
+ struct iovec *iov, size_t iovlen,
+ int flags,
+ int *ret_fd) {
+
+ CMSG_BUFFER_TYPE(CMSG_SPACE(sizeof(int))) control;
+ struct msghdr mh = {
+ .msg_control = &control,
+ .msg_controllen = sizeof(control),
+ .msg_iov = iov,
+ .msg_iovlen = iovlen,
+ };
+ struct cmsghdr *found;
+ ssize_t k;
+
+ assert(transport_fd >= 0);
+ assert(ret_fd);
+
+ /*
+ * Receive a single FD via @transport_fd. We don't care for
+ * the transport-type. We retrieve a single FD at most, so for
+ * packet-based transports, the caller must ensure to send
+ * only a single FD per packet. This is best used in
+ * combination with send_one_fd().
+ */
+
+ k = recvmsg_safe(transport_fd, &mh, MSG_CMSG_CLOEXEC | flags);
+ if (k < 0)
+ return k;
+
+ found = cmsg_find(&mh, SOL_SOCKET, SCM_RIGHTS, CMSG_LEN(sizeof(int)));
+ if (!found) {
+ cmsg_close_all(&mh);
+
+ /* If didn't receive an FD or any data, return an error. */
+ if (k == 0)
+ return -EIO;
+ }
+
+ if (found)
+ *ret_fd = *CMSG_TYPED_DATA(found, int);
+ else
+ *ret_fd = -EBADF;
+
+ return k;
+}
+
+int receive_one_fd(int transport_fd, int flags) {
+ int fd;
+ ssize_t k;
+
+ k = receive_one_fd_iov(transport_fd, NULL, 0, flags, &fd);
+ if (k == 0)
+ return fd;
+
+ /* k must be negative, since receive_one_fd_iov() only returns
+ * a positive value if data was received through the iov. */
+ assert(k < 0);
+ return (int) k;
+}
+
+ssize_t next_datagram_size_fd(int fd) {
+ ssize_t l;
+ int k;
+
+ /* This is a bit like FIONREAD/SIOCINQ, however a bit more powerful. The difference being: recv(MSG_PEEK) will
+ * actually cause the next datagram in the queue to be validated regarding checksums, which FIONREAD doesn't
+ * do. This difference is actually of major importance as we need to be sure that the size returned here
+ * actually matches what we will read with recvmsg() next, as otherwise we might end up allocating a buffer of
+ * the wrong size. */
+
+ l = recv(fd, NULL, 0, MSG_PEEK|MSG_TRUNC);
+ if (l < 0) {
+ if (IN_SET(errno, EOPNOTSUPP, EFAULT))
+ goto fallback;
+
+ return -errno;
+ }
+ if (l == 0)
+ goto fallback;
+
+ return l;
+
+fallback:
+ k = 0;
+
+ /* Some sockets (AF_PACKET) do not support null-sized recv() with MSG_TRUNC set, let's fall back to FIONREAD
+ * for them. Checksums don't matter for raw sockets anyway, hence this should be fine. */
+
+ if (ioctl(fd, FIONREAD, &k) < 0)
+ return -errno;
+
+ return (ssize_t) k;
+}
+
+/* Put a limit on how many times will attempt to call accept4(). We loop
+ * only on "transient" errors, but let's make sure we don't loop forever. */
+#define MAX_FLUSH_ITERATIONS 1024
+
+int flush_accept(int fd) {
+
+ int r, b;
+ socklen_t l = sizeof(b);
+
+ /* Similar to flush_fd() but flushes all incoming connections by accepting and immediately closing
+ * them. */
+
+ if (getsockopt(fd, SOL_SOCKET, SO_ACCEPTCONN, &b, &l) < 0)
+ return -errno;
+
+ assert(l == sizeof(b));
+ if (!b) /* Let's check if this socket accepts connections before calling accept(). accept4() can
+ * return EOPNOTSUPP if the fd is not a listening socket, which we should treat as a fatal
+ * error, or in case the incoming TCP connection triggered a network issue, which we want to
+ * treat as a transient error. Thus, let's rule out the first reason for EOPNOTSUPP early, so
+ * we can loop safely on transient errors below. */
+ return -ENOTTY;
+
+ for (unsigned iteration = 0;; iteration++) {
+ int cfd;
+
+ r = fd_wait_for_event(fd, POLLIN, 0);
+ if (r < 0) {
+ if (r == -EINTR)
+ continue;
+
+ return r;
+ }
+ if (r == 0)
+ return 0;
+
+ if (iteration >= MAX_FLUSH_ITERATIONS)
+ return log_debug_errno(SYNTHETIC_ERRNO(EBUSY),
+ "Failed to flush connections within " STRINGIFY(MAX_FLUSH_ITERATIONS) " iterations.");
+
+ cfd = accept4(fd, NULL, NULL, SOCK_NONBLOCK|SOCK_CLOEXEC);
+ if (cfd < 0) {
+ if (errno == EAGAIN)
+ return 0;
+
+ if (ERRNO_IS_ACCEPT_AGAIN(errno))
+ continue;
+
+ return -errno;
+ }
+
+ safe_close(cfd);
+ }
+}
+
+struct cmsghdr* cmsg_find(struct msghdr *mh, int level, int type, socklen_t length) {
+ struct cmsghdr *cmsg;
+
+ assert(mh);
+
+ CMSG_FOREACH(cmsg, mh)
+ if (cmsg->cmsg_level == level &&
+ cmsg->cmsg_type == type &&
+ (length == (socklen_t) -1 || length == cmsg->cmsg_len))
+ return cmsg;
+
+ return NULL;
+}
+
+void* cmsg_find_and_copy_data(struct msghdr *mh, int level, int type, void *buf, size_t buf_len) {
+ struct cmsghdr *cmsg;
+
+ assert(mh);
+ assert(buf);
+ assert(buf_len > 0);
+
+ /* This is similar to cmsg_find_data(), but copy the found data to buf. This should be typically used
+ * when reading possibly unaligned data such as timestamp, as time_t is 64-bit and size_t is 32-bit on
+ * RISCV32. See issue #27241. */
+
+ cmsg = cmsg_find(mh, level, type, CMSG_LEN(buf_len));
+ if (!cmsg)
+ return NULL;
+
+ return memcpy_safe(buf, CMSG_DATA(cmsg), buf_len);
+}
+
+int socket_ioctl_fd(void) {
+ int fd;
+
+ /* Create a socket to invoke the various network interface ioctl()s on. Traditionally only AF_INET was good for
+ * that. Since kernel 4.6 AF_NETLINK works for this too. We first try to use AF_INET hence, but if that's not
+ * available (for example, because it is made unavailable via SECCOMP or such), we'll fall back to the more
+ * generic AF_NETLINK. */
+
+ fd = socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC, 0);
+ if (fd < 0)
+ fd = socket(AF_NETLINK, SOCK_RAW|SOCK_CLOEXEC, NETLINK_GENERIC);
+ if (fd < 0)
+ return -errno;
+
+ return fd;
+}
+
+int sockaddr_un_unlink(const struct sockaddr_un *sa) {
+ const char *p, * nul;
+
+ assert(sa);
+
+ if (sa->sun_family != AF_UNIX)
+ return -EPROTOTYPE;
+
+ if (sa->sun_path[0] == 0) /* Nothing to do for abstract sockets */
+ return 0;
+
+ /* The path in .sun_path is not necessarily NUL terminated. Let's fix that. */
+ nul = memchr(sa->sun_path, 0, sizeof(sa->sun_path));
+ if (nul)
+ p = sa->sun_path;
+ else
+ p = memdupa_suffix0(sa->sun_path, sizeof(sa->sun_path));
+
+ if (unlink(p) < 0)
+ return -errno;
+
+ return 1;
+}
+
+int sockaddr_un_set_path(struct sockaddr_un *ret, const char *path) {
+ size_t l;
+
+ assert(ret);
+ assert(path);
+
+ /* Initialize ret->sun_path from the specified argument. This will interpret paths starting with '@' as
+ * abstract namespace sockets, and those starting with '/' as regular filesystem sockets. It won't accept
+ * anything else (i.e. no relative paths), to avoid ambiguities. Note that this function cannot be used to
+ * reference paths in the abstract namespace that include NUL bytes in the name. */
+
+ l = strlen(path);
+ if (l < 2)
+ return -EINVAL;
+ if (!IN_SET(path[0], '/', '@'))
+ return -EINVAL;
+
+ /* Don't allow paths larger than the space in sockaddr_un. Note that we are a tiny bit more restrictive than
+ * the kernel is: we insist on NUL termination (both for abstract namespace and regular file system socket
+ * addresses!), which the kernel doesn't. We do this to reduce chance of incompatibility with other apps that
+ * do not expect non-NUL terminated file system path. */
+ if (l+1 > sizeof(ret->sun_path))
+ return path[0] == '@' ? -EINVAL : -ENAMETOOLONG; /* return a recognizable error if this is
+ * too long to fit into a sockaddr_un, but
+ * is a file system path, and thus might be
+ * connectible via O_PATH indirection. */
+
+ *ret = (struct sockaddr_un) {
+ .sun_family = AF_UNIX,
+ };
+
+ if (path[0] == '@') {
+ /* Abstract namespace socket */
+ memcpy(ret->sun_path + 1, path + 1, l); /* copy *with* trailing NUL byte */
+ return (int) (offsetof(struct sockaddr_un, sun_path) + l); /* 🔥 *don't* 🔥 include trailing NUL in size */
+
+ } else {
+ assert(path[0] == '/');
+
+ /* File system socket */
+ memcpy(ret->sun_path, path, l + 1); /* copy *with* trailing NUL byte */
+ return (int) (offsetof(struct sockaddr_un, sun_path) + l + 1); /* include trailing NUL in size */
+ }
+}
+
+int socket_bind_to_ifname(int fd, const char *ifname) {
+ assert(fd >= 0);
+
+ /* Call with NULL to drop binding */
+
+ return RET_NERRNO(setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen_ptr(ifname)));
+}
+
+int socket_bind_to_ifindex(int fd, int ifindex) {
+ char ifname[IF_NAMESIZE];
+ int r;
+
+ assert(fd >= 0);
+
+ if (ifindex <= 0)
+ /* Drop binding */
+ return RET_NERRNO(setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, NULL, 0));
+
+ r = setsockopt_int(fd, SOL_SOCKET, SO_BINDTOIFINDEX, ifindex);
+ if (r != -ENOPROTOOPT)
+ return r;
+
+ /* Fall back to SO_BINDTODEVICE on kernels < 5.0 which didn't have SO_BINDTOIFINDEX */
+ r = format_ifname(ifindex, ifname);
+ if (r < 0)
+ return r;
+
+ return socket_bind_to_ifname(fd, ifname);
+}
+
+ssize_t recvmsg_safe(int sockfd, struct msghdr *msg, int flags) {
+ ssize_t n;
+
+ /* A wrapper around recvmsg() that checks for MSG_CTRUNC, and turns it into an error, in a reasonably
+ * safe way, closing any SCM_RIGHTS fds in the error path.
+ *
+ * Note that unlike our usual coding style this might modify *msg on failure. */
+
+ n = recvmsg(sockfd, msg, flags);
+ if (n < 0)
+ return -errno;
+
+ if (FLAGS_SET(msg->msg_flags, MSG_CTRUNC)) {
+ cmsg_close_all(msg);
+ return -EXFULL; /* a recognizable error code */
+ }
+
+ return n;
+}
+
+int socket_get_family(int fd) {
+ int af;
+ socklen_t sl = sizeof(af);
+
+ if (getsockopt(fd, SOL_SOCKET, SO_DOMAIN, &af, &sl) < 0)
+ return -errno;
+
+ if (sl != sizeof(af))
+ return -EINVAL;
+
+ return af;
+}
+
+int socket_set_recvpktinfo(int fd, int af, bool b) {
+
+ if (af == AF_UNSPEC) {
+ af = socket_get_family(fd);
+ if (af < 0)
+ return af;
+ }
+
+ switch (af) {
+
+ case AF_INET:
+ return setsockopt_int(fd, IPPROTO_IP, IP_PKTINFO, b);
+
+ case AF_INET6:
+ return setsockopt_int(fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, b);
+
+ case AF_NETLINK:
+ return setsockopt_int(fd, SOL_NETLINK, NETLINK_PKTINFO, b);
+
+ case AF_PACKET:
+ return setsockopt_int(fd, SOL_PACKET, PACKET_AUXDATA, b);
+
+ default:
+ return -EAFNOSUPPORT;
+ }
+}
+
+int socket_set_unicast_if(int fd, int af, int ifi) {
+ be32_t ifindex_be = htobe32(ifi);
+
+ if (af == AF_UNSPEC) {
+ af = socket_get_family(fd);
+ if (af < 0)
+ return af;
+ }
+
+ switch (af) {
+
+ case AF_INET:
+ return RET_NERRNO(setsockopt(fd, IPPROTO_IP, IP_UNICAST_IF, &ifindex_be, sizeof(ifindex_be)));
+
+ case AF_INET6:
+ return RET_NERRNO(setsockopt(fd, IPPROTO_IPV6, IPV6_UNICAST_IF, &ifindex_be, sizeof(ifindex_be)));
+
+ default:
+ return -EAFNOSUPPORT;
+ }
+}
+
+int socket_set_option(int fd, int af, int opt_ipv4, int opt_ipv6, int val) {
+ if (af == AF_UNSPEC) {
+ af = socket_get_family(fd);
+ if (af < 0)
+ return af;
+ }
+
+ switch (af) {
+
+ case AF_INET:
+ return setsockopt_int(fd, IPPROTO_IP, opt_ipv4, val);
+
+ case AF_INET6:
+ return setsockopt_int(fd, IPPROTO_IPV6, opt_ipv6, val);
+
+ default:
+ return -EAFNOSUPPORT;
+ }
+}
+
+int socket_get_mtu(int fd, int af, size_t *ret) {
+ int mtu, r;
+
+ if (af == AF_UNSPEC) {
+ af = socket_get_family(fd);
+ if (af < 0)
+ return af;
+ }
+
+ switch (af) {
+
+ case AF_INET:
+ r = getsockopt_int(fd, IPPROTO_IP, IP_MTU, &mtu);
+ break;
+
+ case AF_INET6:
+ r = getsockopt_int(fd, IPPROTO_IPV6, IPV6_MTU, &mtu);
+ break;
+
+ default:
+ return -EAFNOSUPPORT;
+ }
+
+ if (r < 0)
+ return r;
+ if (mtu <= 0)
+ return -EINVAL;
+
+ *ret = (size_t) mtu;
+ return 0;
+}
+
+static int connect_unix_path_simple(int fd, const char *path) {
+ union sockaddr_union sa = {
+ .un.sun_family = AF_UNIX,
+ };
+ size_t l;
+
+ assert(fd >= 0);
+ assert(path);
+
+ l = strlen(path);
+ assert(l > 0);
+ assert(l < sizeof(sa.un.sun_path));
+
+ memcpy(sa.un.sun_path, path, l + 1);
+ return RET_NERRNO(connect(fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + l + 1));
+}
+
+static int connect_unix_inode(int fd, int inode_fd) {
+ assert(fd >= 0);
+ assert(inode_fd >= 0);
+
+ return connect_unix_path_simple(fd, FORMAT_PROC_FD_PATH(inode_fd));
+}
+
+int connect_unix_path(int fd, int dir_fd, const char *path) {
+ _cleanup_close_ int inode_fd = -EBADF;
+
+ assert(fd >= 0);
+ assert(dir_fd == AT_FDCWD || dir_fd >= 0);
+
+ /* Connects to the specified AF_UNIX socket in the file system. Works around the 108 byte size limit
+ * in sockaddr_un, by going via O_PATH if needed. This hence works for any kind of path. */
+
+ if (!path)
+ return connect_unix_inode(fd, dir_fd); /* If no path is specified, then dir_fd refers to the socket inode to connect to. */
+
+ /* Refuse zero length path early, to make sure AF_UNIX stack won't mistake this for an abstract
+ * namespace path, since first char is NUL */
+ if (isempty(path))
+ return -EINVAL;
+
+ /* Shortcut for the simple case */
+ if (dir_fd == AT_FDCWD && strlen(path) < sizeof_field(struct sockaddr_un, sun_path))
+ return connect_unix_path_simple(fd, path);
+
+ /* If dir_fd is specified, then we need to go the indirect O_PATH route, because connectat() does not
+ * exist. If the path is too long, we also need to take the indirect route, since we can't fit this
+ * into a sockaddr_un directly. */
+
+ inode_fd = openat(dir_fd, path, O_PATH|O_CLOEXEC);
+ if (inode_fd < 0)
+ return -errno;
+
+ return connect_unix_inode(fd, inode_fd);
+}
+
+int socket_address_parse_unix(SocketAddress *ret_address, const char *s) {
+ struct sockaddr_un un;
+ int r;
+
+ assert(ret_address);
+ assert(s);
+
+ if (!IN_SET(*s, '/', '@'))
+ return -EPROTO;
+
+ r = sockaddr_un_set_path(&un, s);
+ if (r < 0)
+ return r;
+
+ *ret_address = (SocketAddress) {
+ .sockaddr.un = un,
+ .size = r,
+ };
+
+ return 0;
+}
+
+int socket_address_parse_vsock(SocketAddress *ret_address, const char *s) {
+ /* AF_VSOCK socket in vsock:cid:port notation */
+ _cleanup_free_ char *n = NULL;
+ char *e, *cid_start;
+ unsigned port, cid;
+ int type, r;
+
+ assert(ret_address);
+ assert(s);
+
+ if ((cid_start = startswith(s, "vsock:")))
+ type = 0;
+ else if ((cid_start = startswith(s, "vsock-dgram:")))
+ type = SOCK_DGRAM;
+ else if ((cid_start = startswith(s, "vsock-seqpacket:")))
+ type = SOCK_SEQPACKET;
+ else if ((cid_start = startswith(s, "vsock-stream:")))
+ type = SOCK_STREAM;
+ else
+ return -EPROTO;
+
+ e = strchr(cid_start, ':');
+ if (!e)
+ return -EINVAL;
+
+ r = safe_atou(e+1, &port);
+ if (r < 0)
+ return r;
+
+ n = strndup(cid_start, e - cid_start);
+ if (!n)
+ return -ENOMEM;
+
+ if (isempty(n))
+ cid = VMADDR_CID_ANY;
+ else {
+ r = safe_atou(n, &cid);
+ if (r < 0)
+ return r;
+ }
+
+ *ret_address = (SocketAddress) {
+ .sockaddr.vm = {
+ .svm_cid = cid,
+ .svm_family = AF_VSOCK,
+ .svm_port = port,
+ },
+ .type = type,
+ .size = sizeof(struct sockaddr_vm),
+ };
+
+ return 0;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-19 23:58:55 +0000