diff options
Diffstat (limited to 'src/basic/socket-util.h')
| -rw-r--r-- | src/basic/socket-util.h | 343 |
1 files changed, 343 insertions, 0 deletions
diff --git a/src/basic/socket-util.h b/src/basic/socket-util.h new file mode 100644 index 0000000..7803168 --- /dev/null +++ b/src/basic/socket-util.h @@ -0,0 +1,343 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +#pragma once + +#include <inttypes.h> +#include <linux/netlink.h> +#include <linux/if_ether.h> +#include <linux/if_infiniband.h> +#include <linux/if_packet.h> +#include <netinet/in.h> +#include <stdbool.h> +#include <stddef.h> +#include <string.h> +#include <sys/socket.h> +#include <sys/types.h> +#include <sys/un.h> + +#include "errno-util.h" +#include "in-addr-util.h" +#include "macro.h" +#include "missing_network.h" +#include "missing_socket.h" +#include "sparse-endian.h" + +union sockaddr_union { + /* The minimal, abstract version */ + struct sockaddr sa; + + /* The libc provided version that allocates "enough room" for every protocol */ + struct sockaddr_storage storage; + + /* Protoctol-specific implementations */ + struct sockaddr_in in; + struct sockaddr_in6 in6; + struct sockaddr_un un; + struct sockaddr_nl nl; + struct sockaddr_ll ll; + struct sockaddr_vm vm; + + /* Ensure there is enough space to store Infiniband addresses */ + uint8_t ll_buffer[offsetof(struct sockaddr_ll, sll_addr) + CONST_MAX(ETH_ALEN, INFINIBAND_ALEN)]; + + /* Ensure there is enough space after the AF_UNIX sun_path for one more NUL byte, just to be sure that the path + * component is always followed by at least one NUL byte. */ + uint8_t un_buffer[sizeof(struct sockaddr_un) + 1]; +}; + +#define SUN_PATH_LEN (sizeof(((struct sockaddr_un){}).sun_path)) + +typedef struct SocketAddress { + union sockaddr_union sockaddr; + + /* We store the size here explicitly due to the weird + * sockaddr_un semantics for abstract sockets */ + socklen_t size; + + /* Socket type, i.e. SOCK_STREAM, SOCK_DGRAM, ... */ + int type; + + /* Socket protocol, IPPROTO_xxx, usually 0, except for netlink */ + int protocol; +} SocketAddress; + +typedef enum SocketAddressBindIPv6Only { + SOCKET_ADDRESS_DEFAULT, + SOCKET_ADDRESS_BOTH, + SOCKET_ADDRESS_IPV6_ONLY, + _SOCKET_ADDRESS_BIND_IPV6_ONLY_MAX, + _SOCKET_ADDRESS_BIND_IPV6_ONLY_INVALID = -EINVAL, +} SocketAddressBindIPv6Only; + +#define socket_address_family(a) ((a)->sockaddr.sa.sa_family) + +const char* socket_address_type_to_string(int t) _const_; +int socket_address_type_from_string(const char *s) _pure_; + +int sockaddr_un_unlink(const struct sockaddr_un *sa); + +static inline int socket_address_unlink(const SocketAddress *a) { + return socket_address_family(a) == AF_UNIX ? sockaddr_un_unlink(&a->sockaddr.un) : 0; +} + +bool socket_address_can_accept(const SocketAddress *a) _pure_; + +int socket_address_listen( + const SocketAddress *a, + int flags, + int backlog, + SocketAddressBindIPv6Only only, + const char *bind_to_device, + bool reuse_port, + bool free_bind, + bool transparent, + mode_t directory_mode, + mode_t socket_mode, + const char *label); + +int socket_address_verify(const SocketAddress *a, bool strict) _pure_; +int socket_address_print(const SocketAddress *a, char **p); +bool socket_address_matches_fd(const SocketAddress *a, int fd); + +bool socket_address_equal(const SocketAddress *a, const SocketAddress *b) _pure_; + +const char* socket_address_get_path(const SocketAddress *a); + +bool socket_ipv6_is_supported(void); +bool socket_ipv6_is_enabled(void); + +int sockaddr_port(const struct sockaddr *_sa, unsigned *port); +const union in_addr_union *sockaddr_in_addr(const struct sockaddr *sa); +int sockaddr_set_in_addr(union sockaddr_union *u, int family, const union in_addr_union *a, uint16_t port); + +int sockaddr_pretty(const struct sockaddr *_sa, socklen_t salen, bool translate_ipv6, bool include_port, char **ret); +int getpeername_pretty(int fd, bool include_port, char **ret); +int getsockname_pretty(int fd, char **ret); + +int socknameinfo_pretty(union sockaddr_union *sa, socklen_t salen, char **_ret); + +const char* socket_address_bind_ipv6_only_to_string(SocketAddressBindIPv6Only b) _const_; +SocketAddressBindIPv6Only socket_address_bind_ipv6_only_from_string(const char *s) _pure_; +SocketAddressBindIPv6Only socket_address_bind_ipv6_only_or_bool_from_string(const char *s); + +int netlink_family_to_string_alloc(int b, char **s); +int netlink_family_from_string(const char *s) _pure_; + +bool sockaddr_equal(const union sockaddr_union *a, const union sockaddr_union *b); + +int fd_set_sndbuf(int fd, size_t n, bool increase); +static inline int fd_inc_sndbuf(int fd, size_t n) { + return fd_set_sndbuf(fd, n, true); +} +int fd_set_rcvbuf(int fd, size_t n, bool increase); +static inline int fd_increase_rxbuf(int fd, size_t n) { + return fd_set_rcvbuf(fd, n, true); +} + +int ip_tos_to_string_alloc(int i, char **s); +int ip_tos_from_string(const char *s); + +typedef enum { + IFNAME_VALID_ALTERNATIVE = 1 << 0, /* Allow "altnames" too */ + IFNAME_VALID_NUMERIC = 1 << 1, /* Allow decimal formatted ifindexes too */ + IFNAME_VALID_SPECIAL = 1 << 2, /* Allow the special names "all" and "default" */ + _IFNAME_VALID_ALL = IFNAME_VALID_ALTERNATIVE | IFNAME_VALID_NUMERIC | IFNAME_VALID_SPECIAL, +} IfnameValidFlags; +bool ifname_valid_char(char a); +bool ifname_valid_full(const char *p, IfnameValidFlags flags); +static inline bool ifname_valid(const char *p) { + return ifname_valid_full(p, 0); +} +bool address_label_valid(const char *p); + +int getpeercred(int fd, struct ucred *ucred); +int getpeersec(int fd, char **ret); +int getpeergroups(int fd, gid_t **ret); + +ssize_t send_one_fd_iov_sa( + int transport_fd, + int fd, + const struct iovec *iov, size_t iovlen, + const struct sockaddr *sa, socklen_t len, + int flags); +int send_one_fd_sa(int transport_fd, + int fd, + const struct sockaddr *sa, socklen_t len, + int flags); +#define send_one_fd_iov(transport_fd, fd, iov, iovlen, flags) send_one_fd_iov_sa(transport_fd, fd, iov, iovlen, NULL, 0, flags) +#define send_one_fd(transport_fd, fd, flags) send_one_fd_iov_sa(transport_fd, fd, NULL, 0, NULL, 0, flags) +ssize_t receive_one_fd_iov(int transport_fd, struct iovec *iov, size_t iovlen, int flags, int *ret_fd); +int receive_one_fd(int transport_fd, int flags); + +ssize_t next_datagram_size_fd(int fd); + +int flush_accept(int fd); + +#define CMSG_FOREACH(cmsg, mh) \ + for ((cmsg) = CMSG_FIRSTHDR(mh); (cmsg); (cmsg) = CMSG_NXTHDR((mh), (cmsg))) + +struct cmsghdr* cmsg_find(struct msghdr *mh, int level, int type, socklen_t length); + +/* Type-safe, dereferencing version of cmsg_find() */ +#define CMSG_FIND_DATA(mh, level, type, ctype) \ + ({ \ + struct cmsghdr *_found; \ + _found = cmsg_find(mh, level, type, CMSG_LEN(sizeof(ctype))); \ + (ctype*) (_found ? CMSG_DATA(_found) : NULL); \ + }) + +/* Resolves to a type that can carry cmsghdr structures. Make sure things are properly aligned, i.e. the type + * itself is placed properly in memory and the size is also aligned to what's appropriate for "cmsghdr" + * structures. */ +#define CMSG_BUFFER_TYPE(size) \ + union { \ + struct cmsghdr cmsghdr; \ + uint8_t buf[size]; \ + uint8_t align_check[(size) >= CMSG_SPACE(0) && \ + (size) == CMSG_ALIGN(size) ? 1 : -1]; \ + } + +/* + * Certain hardware address types (e.g Infiniband) do not fit into sll_addr + * (8 bytes) and run over the structure. This macro returns the correct size that + * must be passed to kernel. + */ +#define SOCKADDR_LL_LEN(sa) \ + ({ \ + const struct sockaddr_ll *_sa = &(sa); \ + size_t _mac_len = sizeof(_sa->sll_addr); \ + assert(_sa->sll_family == AF_PACKET); \ + if (be16toh(_sa->sll_hatype) == ARPHRD_ETHER) \ + _mac_len = MAX(_mac_len, (size_t) ETH_ALEN); \ + if (be16toh(_sa->sll_hatype) == ARPHRD_INFINIBAND) \ + _mac_len = MAX(_mac_len, (size_t) INFINIBAND_ALEN); \ + offsetof(struct sockaddr_ll, sll_addr) + _mac_len; \ + }) + +/* Covers only file system and abstract AF_UNIX socket addresses, but not unnamed socket addresses. */ +#define SOCKADDR_UN_LEN(sa) \ + ({ \ + const struct sockaddr_un *_sa = &(sa); \ + assert(_sa->sun_family == AF_UNIX); \ + offsetof(struct sockaddr_un, sun_path) + \ + (_sa->sun_path[0] == 0 ? \ + 1 + strnlen(_sa->sun_path+1, sizeof(_sa->sun_path)-1) : \ + strnlen(_sa->sun_path, sizeof(_sa->sun_path))+1); \ + }) + +#define SOCKADDR_LEN(saddr) \ + ({ \ + const union sockaddr_union *__sa = &(saddr); \ + size_t _len; \ + switch (__sa->sa.sa_family) { \ + case AF_INET: \ + _len = sizeof(struct sockaddr_in); \ + break; \ + case AF_INET6: \ + _len = sizeof(struct sockaddr_in6); \ + break; \ + case AF_UNIX: \ + _len = SOCKADDR_UN_LEN(__sa->un); \ + break; \ + case AF_PACKET: \ + _len = SOCKADDR_LL_LEN(__sa->ll); \ + break; \ + case AF_NETLINK: \ + _len = sizeof(struct sockaddr_nl); \ + break; \ + case AF_VSOCK: \ + _len = sizeof(struct sockaddr_vm); \ + break; \ + default: \ + assert_not_reached(); \ + } \ + _len; \ + }) + +int socket_ioctl_fd(void); + +int sockaddr_un_set_path(struct sockaddr_un *ret, const char *path); + +static inline int setsockopt_int(int fd, int level, int optname, int value) { + if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0) + return -errno; + + return 0; +} + +static inline int getsockopt_int(int fd, int level, int optname, int *ret) { + int v; + socklen_t sl = sizeof(v); + + if (getsockopt(fd, level, optname, &v, &sl) < 0) + return negative_errno(); + if (sl != sizeof(v)) + return -EIO; + + *ret = v; + return 0; +} + +int socket_bind_to_ifname(int fd, const char *ifname); +int socket_bind_to_ifindex(int fd, int ifindex); + +/* Define a 64bit version of timeval/timespec in any case, even on 32bit userspace. */ +struct timeval_large { + uint64_t tvl_sec, tvl_usec; +}; +struct timespec_large { + uint64_t tvl_sec, tvl_nsec; +}; + +/* glibc duplicates timespec/timeval on certain 32bit archs, once in 32bit and once in 64bit. + * See __convert_scm_timestamps() in glibc source code. Hence, we need additional buffer space for them + * to prevent from recvmsg_safe() returning -EXFULL. */ +#define CMSG_SPACE_TIMEVAL \ + ((sizeof(struct timeval) == sizeof(struct timeval_large)) ? \ + CMSG_SPACE(sizeof(struct timeval)) : \ + CMSG_SPACE(sizeof(struct timeval)) + \ + CMSG_SPACE(sizeof(struct timeval_large))) +#define CMSG_SPACE_TIMESPEC \ + ((sizeof(struct timespec) == sizeof(struct timespec_large)) ? \ + CMSG_SPACE(sizeof(struct timespec)) : \ + CMSG_SPACE(sizeof(struct timespec)) + \ + CMSG_SPACE(sizeof(struct timespec_large))) + +ssize_t recvmsg_safe(int sockfd, struct msghdr *msg, int flags); + +int socket_get_family(int fd); +int socket_set_recvpktinfo(int fd, int af, bool b); +int socket_set_unicast_if(int fd, int af, int ifi); + +int socket_set_option(int fd, int af, int opt_ipv4, int opt_ipv6, int val); +static inline int socket_set_recverr(int fd, int af, bool b) { + return socket_set_option(fd, af, IP_RECVERR, IPV6_RECVERR, b); +} +static inline int socket_set_recvttl(int fd, int af, bool b) { + return socket_set_option(fd, af, IP_RECVTTL, IPV6_RECVHOPLIMIT, b); +} +static inline int socket_set_ttl(int fd, int af, int ttl) { + return socket_set_option(fd, af, IP_TTL, IPV6_UNICAST_HOPS, ttl); +} +static inline int socket_set_freebind(int fd, int af, bool b) { + return socket_set_option(fd, af, IP_FREEBIND, IPV6_FREEBIND, b); +} +static inline int socket_set_transparent(int fd, int af, bool b) { + return socket_set_option(fd, af, IP_TRANSPARENT, IPV6_TRANSPARENT, b); +} +static inline int socket_set_recvfragsize(int fd, int af, bool b) { + return socket_set_option(fd, af, IP_RECVFRAGSIZE, IPV6_RECVFRAGSIZE, b); +} + +int socket_get_mtu(int fd, int af, size_t *ret); + +/* an initializer for struct ucred that initialized all fields to the invalid value appropriate for each */ +#define UCRED_INVALID { .pid = 0, .uid = UID_INVALID, .gid = GID_INVALID } + +int connect_unix_path(int fd, int dir_fd, const char *path); + +/* libc's SOMAXCONN is defined to 128 or 4096 (at least on glibc). But actually, the value can be much + * larger. In our codebase we want to set it to the max usually, since noawadays socket memory is properly + * tracked by memcg, and hence we don't need to enforce extra limits here. Moreover, the kernel caps it to + * /proc/sys/net/core/somaxconn anyway, thus by setting this to unbounded we just make that sysctl file + * authoritative. */ +#define SOMAXCONN_DELUXE INT_MAX |