src/basic/socket-util.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 #include <inttypes.h>
   5 #include <linux/netlink.h>
   6 #include <linux/if_ether.h>
   7 #include <linux/if_infiniband.h>
   8 #include <linux/if_packet.h>
   9 #include <netinet/in.h>
  10 #include <stdbool.h>
  11 #include <stddef.h>
  12 #include <string.h>
  13 #include <sys/socket.h>
  14 #include <sys/types.h>
  15 #include <sys/un.h>
  16
  17 #include "macro.h"
  18 #include "missing_socket.h"
  19 #include "sparse-endian.h"
  20
  21 union sockaddr_union {
  22         /* The minimal, abstract version */
  23         struct sockaddr sa;
  24
  25         /* The libc provided version that allocates "enough room" for every protocol */
  26         struct sockaddr_storage storage;
  27
  28         /* Protoctol-specific implementations */
  29         struct sockaddr_in in;
  30         struct sockaddr_in6 in6;
  31         struct sockaddr_un un;
  32         struct sockaddr_nl nl;
  33         struct sockaddr_ll ll;
  34         struct sockaddr_vm vm;
  35
  36         /* Ensure there is enough space to store Infiniband addresses */
  37         uint8_t ll_buffer[offsetof(struct sockaddr_ll, sll_addr) + CONST_MAX(ETH_ALEN, INFINIBAND_ALEN)];
  38
  39         /* Ensure there is enough space after the AF_UNIX sun_path for one more NUL byte, just to be sure that the path
  40          * component is always followed by at least one NUL byte. */
  41         uint8_t un_buffer[sizeof(struct sockaddr_un) + 1];
  42 };
  43
  44 #define SUN_PATH_LEN (sizeof(((struct sockaddr_un){}).sun_path))
  45
  46 typedef struct SocketAddress {
  47         union sockaddr_union sockaddr;
  48
  49         /* We store the size here explicitly due to the weird
  50          * sockaddr_un semantics for abstract sockets */
  51         socklen_t size;
  52
  53         /* Socket type, i.e. SOCK_STREAM, SOCK_DGRAM, ... */
  54         int type;
  55
  56         /* Socket protocol, IPPROTO_xxx, usually 0, except for netlink */
  57         int protocol;
  58 } SocketAddress;
  59
  60 typedef enum SocketAddressBindIPv6Only {
  61         SOCKET_ADDRESS_DEFAULT,
  62         SOCKET_ADDRESS_BOTH,
  63         SOCKET_ADDRESS_IPV6_ONLY,
  64         _SOCKET_ADDRESS_BIND_IPV6_ONLY_MAX,
  65         _SOCKET_ADDRESS_BIND_IPV6_ONLY_INVALID = -1
  66 } SocketAddressBindIPv6Only;
  67
  68 #define socket_address_family(a) ((a)->sockaddr.sa.sa_family)
  69
  70 const char* socket_address_type_to_string(int t) _const_;
  71 int socket_address_type_from_string(const char *s) _pure_;
  72
  73 int sockaddr_un_unlink(const struct sockaddr_un *sa);
  74
  75 static inline int socket_address_unlink(const SocketAddress *a) {
  76         return socket_address_family(a) == AF_UNIX ? sockaddr_un_unlink(&a->sockaddr.un) : 0;
  77 }
  78
  79 bool socket_address_can_accept(const SocketAddress *a) _pure_;
  80
  81 int socket_address_listen(
  82                 const SocketAddress *a,
  83                 int flags,
  84                 int backlog,
  85                 SocketAddressBindIPv6Only only,
  86                 const char *bind_to_device,
  87                 bool reuse_port,
  88                 bool free_bind,
  89                 bool transparent,
  90                 mode_t directory_mode,
  91                 mode_t socket_mode,
  92                 const char *label);
  93
  94 int socket_address_verify(const SocketAddress *a, bool strict) _pure_;
  95 int socket_address_print(const SocketAddress *a, char **p);
  96 bool socket_address_matches_fd(const SocketAddress *a, int fd);
  97
  98 bool socket_address_equal(const SocketAddress *a, const SocketAddress *b) _pure_;
  99
 100 const char* socket_address_get_path(const SocketAddress *a);
 101
 102 bool socket_ipv6_is_supported(void);
 103
 104 int sockaddr_port(const struct sockaddr *_sa, unsigned *port);
 105
 106 int sockaddr_pretty(const struct sockaddr *_sa, socklen_t salen, bool translate_ipv6, bool include_port, char **ret);
 107 int getpeername_pretty(int fd, bool include_port, char **ret);
 108 int getsockname_pretty(int fd, char **ret);
 109
 110 int socknameinfo_pretty(union sockaddr_union *sa, socklen_t salen, char **_ret);
 111
 112 const char* socket_address_bind_ipv6_only_to_string(SocketAddressBindIPv6Only b) _const_;
 113 SocketAddressBindIPv6Only socket_address_bind_ipv6_only_from_string(const char *s) _pure_;
 114 SocketAddressBindIPv6Only socket_address_bind_ipv6_only_or_bool_from_string(const char *s);
 115
 116 int netlink_family_to_string_alloc(int b, char **s);
 117 int netlink_family_from_string(const char *s) _pure_;
 118
 119 bool sockaddr_equal(const union sockaddr_union *a, const union sockaddr_union *b);
 120
 121 int fd_inc_sndbuf(int fd, size_t n);
 122 int fd_inc_rcvbuf(int fd, size_t n);
 123
 124 int ip_tos_to_string_alloc(int i, char **s);
 125 int ip_tos_from_string(const char *s);
 126
 127 bool ifname_valid_full(const char *p, bool alternative);
 128 static inline bool ifname_valid(const char *p) {
 129         return ifname_valid_full(p, false);
 130 }
 131 bool address_label_valid(const char *p);
 132
 133 int getpeercred(int fd, struct ucred *ucred);
 134 int getpeersec(int fd, char **ret);
 135 int getpeergroups(int fd, gid_t **ret);
 136
 137 ssize_t send_one_fd_iov_sa(
 138                 int transport_fd,
 139                 int fd,
 140                 struct iovec *iov, size_t iovlen,
 141                 const struct sockaddr *sa, socklen_t len,
 142                 int flags);
 143 int send_one_fd_sa(int transport_fd,
 144                    int fd,
 145                    const struct sockaddr *sa, socklen_t len,
 146                    int flags);
 147 #define send_one_fd_iov(transport_fd, fd, iov, iovlen, flags) send_one_fd_iov_sa(transport_fd, fd, iov, iovlen, NULL, 0, flags)
 148 #define send_one_fd(transport_fd, fd, flags) send_one_fd_iov_sa(transport_fd, fd, NULL, 0, NULL, 0, flags)
 149 ssize_t receive_one_fd_iov(int transport_fd, struct iovec *iov, size_t iovlen, int flags, int *ret_fd);
 150 int receive_one_fd(int transport_fd, int flags);
 151
 152 ssize_t next_datagram_size_fd(int fd);
 153
 154 int flush_accept(int fd);
 155
 156 #define CMSG_FOREACH(cmsg, mh)                                          \
 157         for ((cmsg) = CMSG_FIRSTHDR(mh); (cmsg); (cmsg) = CMSG_NXTHDR((mh), (cmsg)))
 158
 159 struct cmsghdr* cmsg_find(struct msghdr *mh, int level, int type, socklen_t length);
 160
 161 /*
 162  * Certain hardware address types (e.g Infiniband) do not fit into sll_addr
 163  * (8 bytes) and run over the structure. This macro returns the correct size that
 164  * must be passed to kernel.
 165  */
 166 #define SOCKADDR_LL_LEN(sa)                                             \
 167         ({                                                              \
 168                 const struct sockaddr_ll *_sa = &(sa);                  \
 169                 size_t _mac_len = sizeof(_sa->sll_addr);                \
 170                 assert(_sa->sll_family == AF_PACKET);                   \
 171                 if (be16toh(_sa->sll_hatype) == ARPHRD_ETHER)           \
 172                         _mac_len = MAX(_mac_len, (size_t) ETH_ALEN);    \
 173                 if (be16toh(_sa->sll_hatype) == ARPHRD_INFINIBAND)      \
 174                         _mac_len = MAX(_mac_len, (size_t) INFINIBAND_ALEN); \
 175                 offsetof(struct sockaddr_ll, sll_addr) + _mac_len;      \
 176         })
 177
 178 /* Covers only file system and abstract AF_UNIX socket addresses, but not unnamed socket addresses. */
 179 #define SOCKADDR_UN_LEN(sa)                                             \
 180         ({                                                              \
 181                 const struct sockaddr_un *_sa = &(sa);                  \
 182                 assert(_sa->sun_family == AF_UNIX);                     \
 183                 offsetof(struct sockaddr_un, sun_path) +                \
 184                         (_sa->sun_path[0] == 0 ?                        \
 185                          1 + strnlen(_sa->sun_path+1, sizeof(_sa->sun_path)-1) : \
 186                          strnlen(_sa->sun_path, sizeof(_sa->sun_path))+1); \
 187         })
 188
 189 int socket_ioctl_fd(void);
 190
 191 int sockaddr_un_set_path(struct sockaddr_un *ret, const char *path);
 192
 193 static inline int setsockopt_int(int fd, int level, int optname, int value) {
 194         if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0)
 195                 return -errno;
 196
 197         return 0;
 198 }
 199
 200 int socket_bind_to_ifname(int fd, const char *ifname);
 201 int socket_bind_to_ifindex(int fd, int ifindex);
 202
 203 ssize_t recvmsg_safe(int sockfd, struct msghdr *msg, int flags);