src/basic/socket-util.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   This file is part of systemd.
   6
   7   Copyright 2010 Lennart Poettering
   8 ***/
   9
  10 #include <netinet/ether.h>
  11 #include <netinet/in.h>
  12 #include <stdbool.h>
  13 #include <stddef.h>
  14 #include <sys/socket.h>
  15 #include <sys/types.h>
  16 #include <sys/un.h>
  17 #include <linux/netlink.h>
  18 #include <linux/if_infiniband.h>
  19 #include <linux/if_packet.h>
  20
  21 #include "macro.h"
  22 #include "missing.h"
  23 #include "util.h"
  24
  25 union sockaddr_union {
  26         /* The minimal, abstract version */
  27         struct sockaddr sa;
  28
  29         /* The libc provided version that allocates "enough room" for every protocol */
  30         struct sockaddr_storage storage;
  31
  32         /* Protoctol-specific implementations */
  33         struct sockaddr_in in;
  34         struct sockaddr_in6 in6;
  35         struct sockaddr_un un;
  36         struct sockaddr_nl nl;
  37         struct sockaddr_ll ll;
  38         struct sockaddr_vm vm;
  39
  40         /* Ensure there is enough space to store Infiniband addresses */
  41         uint8_t ll_buffer[offsetof(struct sockaddr_ll, sll_addr) + CONST_MAX(ETH_ALEN, INFINIBAND_ALEN)];
  42
  43         /* Ensure there is enough space after the AF_UNIX sun_path for one more NUL byte, just to be sure that the path
  44          * component is always followed by at least one NUL byte. */
  45         uint8_t un_buffer[sizeof(struct sockaddr_un) + 1];
  46 };
  47
  48 typedef struct SocketAddress {
  49         union sockaddr_union sockaddr;
  50
  51         /* We store the size here explicitly due to the weird
  52          * sockaddr_un semantics for abstract sockets */
  53         socklen_t size;
  54
  55         /* Socket type, i.e. SOCK_STREAM, SOCK_DGRAM, ... */
  56         int type;
  57
  58         /* Socket protocol, IPPROTO_xxx, usually 0, except for netlink */
  59         int protocol;
  60 } SocketAddress;
  61
  62 typedef enum SocketAddressBindIPv6Only {
  63         SOCKET_ADDRESS_DEFAULT,
  64         SOCKET_ADDRESS_BOTH,
  65         SOCKET_ADDRESS_IPV6_ONLY,
  66         _SOCKET_ADDRESS_BIND_IPV6_ONLY_MAX,
  67         _SOCKET_ADDRESS_BIND_IPV6_ONLY_INVALID = -1
  68 } SocketAddressBindIPv6Only;
  69
  70 #define socket_address_family(a) ((a)->sockaddr.sa.sa_family)
  71
  72 const char* socket_address_type_to_string(int t) _const_;
  73 int socket_address_type_from_string(const char *s) _pure_;
  74
  75 int socket_address_parse(SocketAddress *a, const char *s);
  76 int socket_address_parse_and_warn(SocketAddress *a, const char *s);
  77 int socket_address_parse_netlink(SocketAddress *a, const char *s);
  78 int socket_address_print(const SocketAddress *a, char **p);
  79 int socket_address_verify(const SocketAddress *a) _pure_;
  80 int socket_address_unlink(SocketAddress *a);
  81
  82 bool socket_address_can_accept(const SocketAddress *a) _pure_;
  83
  84 int socket_address_listen(
  85                 const SocketAddress *a,
  86                 int flags,
  87                 int backlog,
  88                 SocketAddressBindIPv6Only only,
  89                 const char *bind_to_device,
  90                 bool reuse_port,
  91                 bool free_bind,
  92                 bool transparent,
  93                 mode_t directory_mode,
  94                 mode_t socket_mode,
  95                 const char *label);
  96 int make_socket_fd(int log_level, const char* address, int type, int flags);
  97
  98 bool socket_address_is(const SocketAddress *a, const char *s, int type);
  99 bool socket_address_is_netlink(const SocketAddress *a, const char *s);
 100
 101 bool socket_address_matches_fd(const SocketAddress *a, int fd);
 102
 103 bool socket_address_equal(const SocketAddress *a, const SocketAddress *b) _pure_;
 104
 105 const char* socket_address_get_path(const SocketAddress *a);
 106
 107 bool socket_ipv6_is_supported(void);
 108
 109 int sockaddr_port(const struct sockaddr *_sa, unsigned *port);
 110
 111 int sockaddr_pretty(const struct sockaddr *_sa, socklen_t salen, bool translate_ipv6, bool include_port, char **ret);
 112 int getpeername_pretty(int fd, bool include_port, char **ret);
 113 int getsockname_pretty(int fd, char **ret);
 114
 115 int socknameinfo_pretty(union sockaddr_union *sa, socklen_t salen, char **_ret);
 116
 117 const char* socket_address_bind_ipv6_only_to_string(SocketAddressBindIPv6Only b) _const_;
 118 SocketAddressBindIPv6Only socket_address_bind_ipv6_only_from_string(const char *s) _pure_;
 119 SocketAddressBindIPv6Only socket_address_bind_ipv6_only_or_bool_from_string(const char *s);
 120
 121 int netlink_family_to_string_alloc(int b, char **s);
 122 int netlink_family_from_string(const char *s) _pure_;
 123
 124 bool sockaddr_equal(const union sockaddr_union *a, const union sockaddr_union *b);
 125
 126 int fd_inc_sndbuf(int fd, size_t n);
 127 int fd_inc_rcvbuf(int fd, size_t n);
 128
 129 int ip_tos_to_string_alloc(int i, char **s);
 130 int ip_tos_from_string(const char *s);
 131
 132 bool ifname_valid(const char *p);
 133 bool address_label_valid(const char *p);
 134
 135 int getpeercred(int fd, struct ucred *ucred);
 136 int getpeersec(int fd, char **ret);
 137 int getpeergroups(int fd, gid_t **ret);
 138
 139 int send_one_fd_sa(int transport_fd,
 140                    int fd,
 141                    const struct sockaddr *sa, socklen_t len,
 142                    int flags);
 143 #define send_one_fd(transport_fd, fd, flags) send_one_fd_sa(transport_fd, fd, NULL, 0, flags)
 144 int receive_one_fd(int transport_fd, int flags);
 145
 146 ssize_t next_datagram_size_fd(int fd);
 147
 148 int flush_accept(int fd);
 149
 150 #define CMSG_FOREACH(cmsg, mh)                                          \
 151         for ((cmsg) = CMSG_FIRSTHDR(mh); (cmsg); (cmsg) = CMSG_NXTHDR((mh), (cmsg)))
 152
 153 struct cmsghdr* cmsg_find(struct msghdr *mh, int level, int type, socklen_t length);
 154
 155 /*
 156  * Certain hardware address types (e.g Infiniband) do not fit into sll_addr
 157  * (8 bytes) and run over the structure. This macro returns the correct size that
 158  * must be passed to kernel.
 159  */
 160 #define SOCKADDR_LL_LEN(sa)                                             \
 161         ({                                                              \
 162                 const struct sockaddr_ll *_sa = &(sa);                  \
 163                 size_t _mac_len = sizeof(_sa->sll_addr);                \
 164                 assert(_sa->sll_family == AF_PACKET);                   \
 165                 if (be16toh(_sa->sll_hatype) == ARPHRD_ETHER)           \
 166                         _mac_len = MAX(_mac_len, (size_t) ETH_ALEN);    \
 167                 if (be16toh(_sa->sll_hatype) == ARPHRD_INFINIBAND)      \
 168                         _mac_len = MAX(_mac_len, (size_t) INFINIBAND_ALEN); \
 169                 offsetof(struct sockaddr_ll, sll_addr) + _mac_len;      \
 170         })
 171
 172 /* Covers only file system and abstract AF_UNIX socket addresses, but not unnamed socket addresses. */
 173 #define SOCKADDR_UN_LEN(sa)                                             \
 174         ({                                                              \
 175                 const struct sockaddr_un *_sa = &(sa);                  \
 176                 assert(_sa->sun_family == AF_UNIX);                     \
 177                 offsetof(struct sockaddr_un, sun_path) +                \
 178                         (_sa->sun_path[0] == 0 ?                        \
 179                          1 + strnlen(_sa->sun_path+1, sizeof(_sa->sun_path)-1) : \
 180                          strnlen(_sa->sun_path, sizeof(_sa->sun_path))); \
 181         })
 182
 183 int socket_ioctl_fd(void);