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   systemd is free software; you can redistribute it and/or modify it
  10   under the terms of the GNU Lesser General Public License as published by
  11   the Free Software Foundation; either version 2.1 of the License, or
  12   (at your option) any later version.
  13
  14   systemd is distributed in the hope that it will be useful, but
  15   WITHOUT ANY WARRANTY; without even the implied warranty of
  16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17   Lesser General Public License for more details.
  18
  19   You should have received a copy of the GNU Lesser General Public License
  20   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  21 ***/
  22
  23 #include <netinet/ether.h>
  24 #include <netinet/in.h>
  25 #include <stdbool.h>
  26 #include <stddef.h>
  27 #include <sys/socket.h>
  28 #include <sys/types.h>
  29 #include <sys/un.h>
  30 #include <linux/netlink.h>
  31 #include <linux/if_infiniband.h>
  32 #include <linux/if_packet.h>
  33
  34 #include "macro.h"
  35 #include "missing.h"
  36 #include "util.h"
  37
  38 union sockaddr_union {
  39         struct sockaddr sa;
  40         struct sockaddr_in in;
  41         struct sockaddr_in6 in6;
  42         struct sockaddr_un un;
  43         struct sockaddr_nl nl;
  44         struct sockaddr_storage storage;
  45         struct sockaddr_ll ll;
  46         struct sockaddr_vm vm;
  47         /* Ensure there is enough space to store Infiniband addresses */
  48         uint8_t ll_buffer[offsetof(struct sockaddr_ll, sll_addr) + CONST_MAX(ETH_ALEN, INFINIBAND_ALEN)];
  49 };
  50
  51 typedef struct SocketAddress {
  52         union sockaddr_union sockaddr;
  53
  54         /* We store the size here explicitly due to the weird
  55          * sockaddr_un semantics for abstract sockets */
  56         socklen_t size;
  57
  58         /* Socket type, i.e. SOCK_STREAM, SOCK_DGRAM, ... */
  59         int type;
  60
  61         /* Socket protocol, IPPROTO_xxx, usually 0, except for netlink */
  62         int protocol;
  63 } SocketAddress;
  64
  65 typedef enum SocketAddressBindIPv6Only {
  66         SOCKET_ADDRESS_DEFAULT,
  67         SOCKET_ADDRESS_BOTH,
  68         SOCKET_ADDRESS_IPV6_ONLY,
  69         _SOCKET_ADDRESS_BIND_IPV6_ONLY_MAX,
  70         _SOCKET_ADDRESS_BIND_IPV6_ONLY_INVALID = -1
  71 } SocketAddressBindIPv6Only;
  72
  73 #define socket_address_family(a) ((a)->sockaddr.sa.sa_family)
  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 int getnameinfo_pretty(int fd, char **ret);
 117
 118 const char* socket_address_bind_ipv6_only_to_string(SocketAddressBindIPv6Only b) _const_;
 119 SocketAddressBindIPv6Only socket_address_bind_ipv6_only_from_string(const char *s) _pure_;
 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
 138 int send_one_fd_sa(int transport_fd,
 139                    int fd,
 140                    const struct sockaddr *sa, socklen_t len,
 141                    int flags);
 142 #define send_one_fd(transport_fd, fd, flags) send_one_fd_sa(transport_fd, fd, NULL, 0, flags)
 143 int receive_one_fd(int transport_fd, int flags);
 144
 145 ssize_t next_datagram_size_fd(int fd);
 146
 147 int flush_accept(int fd);
 148
 149 #define CMSG_FOREACH(cmsg, mh)                                          \
 150         for ((cmsg) = CMSG_FIRSTHDR(mh); (cmsg); (cmsg) = CMSG_NXTHDR((mh), (cmsg)))
 151
 152 struct cmsghdr* cmsg_find(struct msghdr *mh, int level, int type, socklen_t length);
 153
 154 /*
 155  * Certain hardware address types (e.g Infiniband) do not fit into sll_addr
 156  * (8 bytes) and run over the structure. This macro returns the correct size that
 157  * must be passed to kernel.
 158  */
 159 #define SOCKADDR_LL_LEN(sa)                                             \
 160         ({                                                              \
 161                 const struct sockaddr_ll *_sa = &(sa);                  \
 162                 size_t _mac_len = sizeof(_sa->sll_addr);                \
 163                 assert(_sa->sll_family == AF_PACKET);                   \
 164                 if (be16toh(_sa->sll_hatype) == ARPHRD_ETHER)           \
 165                         _mac_len = MAX(_mac_len, (size_t) ETH_ALEN);    \
 166                 if (be16toh(_sa->sll_hatype) == ARPHRD_INFINIBAND)      \
 167                         _mac_len = MAX(_mac_len, (size_t) INFINIBAND_ALEN); \
 168                 offsetof(struct sockaddr_ll, sll_addr) + _mac_len;      \
 169         })
 170
 171 /* Covers only file system and abstract AF_UNIX socket addresses, but not unnamed socket addresses. */
 172 #define SOCKADDR_UN_LEN(sa)                                             \
 173         ({                                                              \
 174                 const struct sockaddr_un *_sa = &(sa);                  \
 175                 assert(_sa->sun_family == AF_UNIX);                     \
 176                 offsetof(struct sockaddr_un, sun_path) +                \
 177                         (_sa->sun_path[0] == 0 ?                        \
 178                          1 + strnlen(_sa->sun_path+1, sizeof(_sa->sun_path)-1) : \
 179                          strnlen(_sa->sun_path, sizeof(_sa->sun_path))); \
 180         })
 181
 182 int socket_ioctl_fd(void);