src/basic/socket-util.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 #include <netinet/ether.h>
   5 #include <netinet/in.h>
   6 #include <stdbool.h>
   7 #include <stddef.h>
   8 #include <sys/socket.h>
   9 #include <sys/types.h>
  10 #include <sys/un.h>
  11 #include <linux/netlink.h>
  12 #include <linux/if_infiniband.h>
  13 #include <linux/if_packet.h>
  14
  15 #include "macro.h"
  16 #include "missing.h"
  17 #include "util.h"
  18
  19 union sockaddr_union {
  20         /* The minimal, abstract version */
  21         struct sockaddr sa;
  22
  23         /* The libc provided version that allocates "enough room" for every protocol */
  24         struct sockaddr_storage storage;
  25
  26         /* Protoctol-specific implementations */
  27         struct sockaddr_in in;
  28         struct sockaddr_in6 in6;
  29         struct sockaddr_un un;
  30         struct sockaddr_nl nl;
  31         struct sockaddr_ll ll;
  32         struct sockaddr_vm vm;
  33
  34         /* Ensure there is enough space to store Infiniband addresses */
  35         uint8_t ll_buffer[offsetof(struct sockaddr_ll, sll_addr) + CONST_MAX(ETH_ALEN, INFINIBAND_ALEN)];
  36
  37         /* Ensure there is enough space after the AF_UNIX sun_path for one more NUL byte, just to be sure that the path
  38          * component is always followed by at least one NUL byte. */
  39         uint8_t un_buffer[sizeof(struct sockaddr_un) + 1];
  40 };
  41
  42 typedef struct SocketAddress {
  43         union sockaddr_union sockaddr;
  44
  45         /* We store the size here explicitly due to the weird
  46          * sockaddr_un semantics for abstract sockets */
  47         socklen_t size;
  48
  49         /* Socket type, i.e. SOCK_STREAM, SOCK_DGRAM, ... */
  50         int type;
  51
  52         /* Socket protocol, IPPROTO_xxx, usually 0, except for netlink */
  53         int protocol;
  54 } SocketAddress;
  55
  56 typedef enum SocketAddressBindIPv6Only {
  57         SOCKET_ADDRESS_DEFAULT,
  58         SOCKET_ADDRESS_BOTH,
  59         SOCKET_ADDRESS_IPV6_ONLY,
  60         _SOCKET_ADDRESS_BIND_IPV6_ONLY_MAX,
  61         _SOCKET_ADDRESS_BIND_IPV6_ONLY_INVALID = -1
  62 } SocketAddressBindIPv6Only;
  63
  64 #define socket_address_family(a) ((a)->sockaddr.sa.sa_family)
  65
  66 const char* socket_address_type_to_string(int t) _const_;
  67 int socket_address_type_from_string(const char *s) _pure_;
  68
  69 int socket_address_parse(SocketAddress *a, const char *s);
  70 int socket_address_parse_and_warn(SocketAddress *a, const char *s);
  71 int socket_address_parse_netlink(SocketAddress *a, const char *s);
  72 int socket_address_print(const SocketAddress *a, char **p);
  73 int socket_address_verify(const SocketAddress *a) _pure_;
  74
  75 int sockaddr_un_unlink(const struct sockaddr_un *sa);
  76
  77 static inline int socket_address_unlink(const SocketAddress *a) {
  78         return socket_address_family(a) == AF_UNIX ? sockaddr_un_unlink(&a->sockaddr.un) : 0;
  79 }
  80
  81 bool socket_address_can_accept(const SocketAddress *a) _pure_;
  82
  83 int socket_address_listen(
  84                 const SocketAddress *a,
  85                 int flags,
  86                 int backlog,
  87                 SocketAddressBindIPv6Only only,
  88                 const char *bind_to_device,
  89                 bool reuse_port,
  90                 bool free_bind,
  91                 bool transparent,
  92                 mode_t directory_mode,
  93                 mode_t socket_mode,
  94                 const char *label);
  95 int make_socket_fd(int log_level, const char* address, int type, int flags);
  96
  97 bool socket_address_is(const SocketAddress *a, const char *s, int type);
  98 bool socket_address_is_netlink(const SocketAddress *a, const char *s);
  99
 100 bool socket_address_matches_fd(const SocketAddress *a, int fd);
 101
 102 bool socket_address_equal(const SocketAddress *a, const SocketAddress *b) _pure_;
 103
 104 const char* socket_address_get_path(const SocketAddress *a);
 105
 106 bool socket_ipv6_is_supported(void);
 107
 108 int sockaddr_port(const struct sockaddr *_sa, unsigned *port);
 109
 110 int sockaddr_pretty(const struct sockaddr *_sa, socklen_t salen, bool translate_ipv6, bool include_port, char **ret);
 111 int getpeername_pretty(int fd, bool include_port, char **ret);
 112 int getsockname_pretty(int fd, char **ret);
 113
 114 int socknameinfo_pretty(union sockaddr_union *sa, socklen_t salen, char **_ret);
 115
 116 const char* socket_address_bind_ipv6_only_to_string(SocketAddressBindIPv6Only b) _const_;
 117 SocketAddressBindIPv6Only socket_address_bind_ipv6_only_from_string(const char *s) _pure_;
 118 SocketAddressBindIPv6Only socket_address_bind_ipv6_only_or_bool_from_string(const char *s);
 119
 120 int netlink_family_to_string_alloc(int b, char **s);
 121 int netlink_family_from_string(const char *s) _pure_;
 122
 123 bool sockaddr_equal(const union sockaddr_union *a, const union sockaddr_union *b);
 124
 125 int fd_inc_sndbuf(int fd, size_t n);
 126 int fd_inc_rcvbuf(int fd, size_t n);
 127
 128 int ip_tos_to_string_alloc(int i, char **s);
 129 int ip_tos_from_string(const char *s);
 130
 131 bool ifname_valid(const char *p);
 132 bool address_label_valid(const char *p);
 133
 134 int getpeercred(int fd, struct ucred *ucred);
 135 int getpeersec(int fd, char **ret);
 136 int getpeergroups(int fd, gid_t **ret);
 137
 138 ssize_t send_one_fd_iov_sa(
 139                 int transport_fd,
 140                 int fd,
 141                 struct iovec *iov, size_t iovlen,
 142                 const struct sockaddr *sa, socklen_t len,
 143                 int flags);
 144 int send_one_fd_sa(int transport_fd,
 145                    int fd,
 146                    const struct sockaddr *sa, socklen_t len,
 147                    int flags);
 148 #define send_one_fd_iov(transport_fd, fd, iov, iovlen, flags) send_one_fd_iov_sa(transport_fd, fd, iov, iovlen, NULL, 0, flags)
 149 #define send_one_fd(transport_fd, fd, flags) send_one_fd_iov_sa(transport_fd, fd, NULL, 0, NULL, 0, flags)
 150 ssize_t receive_one_fd_iov(int transport_fd, struct iovec *iov, size_t iovlen, int flags, int *ret_fd);
 151 int receive_one_fd(int transport_fd, int flags);
 152
 153 ssize_t next_datagram_size_fd(int fd);
 154
 155 int flush_accept(int fd);
 156
 157 #define CMSG_FOREACH(cmsg, mh)                                          \
 158         for ((cmsg) = CMSG_FIRSTHDR(mh); (cmsg); (cmsg) = CMSG_NXTHDR((mh), (cmsg)))
 159
 160 struct cmsghdr* cmsg_find(struct msghdr *mh, int level, int type, socklen_t length);
 161
 162 /*
 163  * Certain hardware address types (e.g Infiniband) do not fit into sll_addr
 164  * (8 bytes) and run over the structure. This macro returns the correct size that
 165  * must be passed to kernel.
 166  */
 167 #define SOCKADDR_LL_LEN(sa)                                             \
 168         ({                                                              \
 169                 const struct sockaddr_ll *_sa = &(sa);                  \
 170                 size_t _mac_len = sizeof(_sa->sll_addr);                \
 171                 assert(_sa->sll_family == AF_PACKET);                   \
 172                 if (be16toh(_sa->sll_hatype) == ARPHRD_ETHER)           \
 173                         _mac_len = MAX(_mac_len, (size_t) ETH_ALEN);    \
 174                 if (be16toh(_sa->sll_hatype) == ARPHRD_INFINIBAND)      \
 175                         _mac_len = MAX(_mac_len, (size_t) INFINIBAND_ALEN); \
 176                 offsetof(struct sockaddr_ll, sll_addr) + _mac_len;      \
 177         })
 178
 179 /* Covers only file system and abstract AF_UNIX socket addresses, but not unnamed socket addresses. */
 180 #define SOCKADDR_UN_LEN(sa)                                             \
 181         ({                                                              \
 182                 const struct sockaddr_un *_sa = &(sa);                  \
 183                 assert(_sa->sun_family == AF_UNIX);                     \
 184                 offsetof(struct sockaddr_un, sun_path) +                \
 185                         (_sa->sun_path[0] == 0 ?                        \
 186                          1 + strnlen(_sa->sun_path+1, sizeof(_sa->sun_path)-1) : \
 187                          strnlen(_sa->sun_path, sizeof(_sa->sun_path))+1); \
 188         })
 189
 190 int socket_ioctl_fd(void);
 191
 192 int sockaddr_un_set_path(struct sockaddr_un *ret, const char *path);
 193
 194 static inline int setsockopt_int(int fd, int level, int optname, int value) {
 195         if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0)
 196                 return -errno;
 197
 198         return 0;
 199 }