diff options
Diffstat (limited to 'shared/systemd/src/basic/socket-util.c')
| -rw-r--r-- | shared/systemd/src/basic/socket-util.c | 1360 |
1 files changed, 0 insertions, 1360 deletions
diff --git a/shared/systemd/src/basic/socket-util.c b/shared/systemd/src/basic/socket-util.c deleted file mode 100644 index e224091d..00000000 --- a/shared/systemd/src/basic/socket-util.c +++ /dev/null @@ -1,1360 +0,0 @@ -/* SPDX-License-Identifier: LGPL-2.1-or-later */ - -#include "nm-sd-adapt-shared.h" - -#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> -#if 0 /* NM_IGNORED */ -#include <linux/if.h> -#endif /* NM_IGNORED */ - -#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 "user-util.h" -#include "utf8.h" - -#if 0 /* NM_IGNORED */ -#if ENABLE_IDN -# define IDN_FLAGS NI_IDN -#else -# define IDN_FLAGS 0 -#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_files_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) { - if (access("/proc/net/if_inet6", F_OK) != 0) - return false; - - return true; -} - -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_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 { - char a[INET6_ADDRSTRLEN], ifname[IF_NAMESIZE + 1]; - - inet_ntop(AF_INET6, &sa->in6.sin6_addr, a, sizeof(a)); - if (sa->in6.sin6_scope_id != 0) - format_ifname_full(sa->in6.sin6_scope_id, ifname, FORMAT_IFNAME_IFINDEX); - - if (include_port) { - r = asprintf(&p, - "[%s]:%u%s%s", - a, - be16toh(sa->in6.sin6_port), - sa->in6.sin6_scope_id != 0 ? "%" : "", - sa->in6.sin6_scope_id != 0 ? ifname : ""); - if (r < 0) - return -ENOMEM; - } else { - p = sa->in6.sin6_scope_id != 0 ? strjoin(a, "%", ifname) : 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 = {}; - - /* 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_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; - - 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; - - for (const char *t = p; *t; t++) { - if ((unsigned char) *t >= 127U) - return false; - - if ((unsigned char) *t <= 32U) - return false; - - if (IN_SET(*t, ':', '/')) - return false; - - numeric = numeric && (*t >= '0' && *t <= '9'); - } - - if (numeric) { - if (!(flags & IFNAME_VALID_NUMERIC)) - return false; - - /* Verify that the number is well-formatted and in range. */ - if (parse_ifindex(p) < 0) - 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_one_fd_iov_sa( - int transport_fd, - int fd, - 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 = 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_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 = *(int*) CMSG_DATA(found); - else - *ret_fd = -1; - - 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; -} -#endif /* NM_IGNORED */ - -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; -} - -#if 0 /* NM_IGNORED */ -/* 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); - } -} -#endif /* NM_IGNORED */ - -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; -} - -#if 0 /* NM_IGNORED */ -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; -} -#endif /* NM_IGNORED */ - -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 -EINVAL; - - *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 */ - - if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen_ptr(ifname)) < 0) - return -errno; - - return 0; -} - -int socket_bind_to_ifindex(int fd, int ifindex) { - char ifname[IF_NAMESIZE + 1]; - int r; - - assert(fd >= 0); - - if (ifindex <= 0) { - /* Drop binding */ - if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, NULL, 0) < 0) - return -errno; - - return 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 */ - if (!format_ifname(ifindex, ifname)) - return -errno; - - 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; -} - -#if 0 /* NM_IGNORED */ -int socket_get_family(int fd, int *ret) { - 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) { - int r; - - if (af == AF_UNSPEC) { - r = socket_get_family(fd, &af); - if (r < 0) - return r; - } - - 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); - int r; - - if (af == AF_UNSPEC) { - r = socket_get_family(fd, &af); - if (r < 0) - return r; - } - - switch (af) { - - case AF_INET: - if (setsockopt(fd, IPPROTO_IP, IP_UNICAST_IF, &ifindex_be, sizeof(ifindex_be)) < 0) - return -errno; - - return 0; - - case AF_INET6: - if (setsockopt(fd, IPPROTO_IPV6, IPV6_UNICAST_IF, &ifindex_be, sizeof(ifindex_be)) < 0) - return -errno; - - return 0; - - default: - return -EAFNOSUPPORT; - } -} - -int socket_set_option(int fd, int af, int opt_ipv4, int opt_ipv6, int val) { - int r; - - if (af == AF_UNSPEC) { - r = socket_get_family(fd, &af); - if (r < 0) - return r; - } - - 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) { - r = socket_get_family(fd, &af); - if (r < 0) - return r; - } - - 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; -} -#endif /* NM_IGNORED */ |