/*------------------------------------------------------------------------- * * ip.c * IPv6-aware network access. * * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * * * IDENTIFICATION * src/common/ip.c * * This file and the IPV6 implementation were initially provided by * Nigel Kukard , Linux Based Systems Design * http://www.lbsd.net. * *------------------------------------------------------------------------- */ #ifndef FRONTEND #include "postgres.h" #else #include "postgres_fe.h" #endif #include #include #include #include #include #ifdef HAVE_NETINET_TCP_H #include #endif #include #include #include "common/ip.h" #ifdef HAVE_UNIX_SOCKETS static int getaddrinfo_unix(const char *path, const struct addrinfo *hintsp, struct addrinfo **result); static int getnameinfo_unix(const struct sockaddr_un *sa, int salen, char *node, int nodelen, char *service, int servicelen, int flags); #endif /* * pg_getaddrinfo_all - get address info for Unix, IPv4 and IPv6 sockets */ int pg_getaddrinfo_all(const char *hostname, const char *servname, const struct addrinfo *hintp, struct addrinfo **result) { int rc; /* not all versions of getaddrinfo() zero *result on failure */ *result = NULL; #ifdef HAVE_UNIX_SOCKETS if (hintp->ai_family == AF_UNIX) return getaddrinfo_unix(servname, hintp, result); #endif /* NULL has special meaning to getaddrinfo(). */ rc = getaddrinfo((!hostname || hostname[0] == '\0') ? NULL : hostname, servname, hintp, result); return rc; } /* * pg_freeaddrinfo_all - free addrinfo structures for IPv4, IPv6, or Unix * * Note: the ai_family field of the original hint structure must be passed * so that we can tell whether the addrinfo struct was built by the system's * getaddrinfo() routine or our own getaddrinfo_unix() routine. Some versions * of getaddrinfo() might be willing to return AF_UNIX addresses, so it's * not safe to look at ai_family in the addrinfo itself. */ void pg_freeaddrinfo_all(int hint_ai_family, struct addrinfo *ai) { #ifdef HAVE_UNIX_SOCKETS if (hint_ai_family == AF_UNIX) { /* struct was built by getaddrinfo_unix (see pg_getaddrinfo_all) */ while (ai != NULL) { struct addrinfo *p = ai; ai = ai->ai_next; free(p->ai_addr); free(p); } } else #endif /* HAVE_UNIX_SOCKETS */ { /* struct was built by getaddrinfo() */ if (ai != NULL) freeaddrinfo(ai); } } /* * pg_getnameinfo_all - get name info for Unix, IPv4 and IPv6 sockets * * The API of this routine differs from the standard getnameinfo() definition * in two ways: first, the addr parameter is declared as sockaddr_storage * rather than struct sockaddr, and second, the node and service fields are * guaranteed to be filled with something even on failure return. */ int pg_getnameinfo_all(const struct sockaddr_storage *addr, int salen, char *node, int nodelen, char *service, int servicelen, int flags) { int rc; #ifdef HAVE_UNIX_SOCKETS if (addr && addr->ss_family == AF_UNIX) rc = getnameinfo_unix((const struct sockaddr_un *) addr, salen, node, nodelen, service, servicelen, flags); else #endif rc = getnameinfo((const struct sockaddr *) addr, salen, node, nodelen, service, servicelen, flags); if (rc != 0) { if (node) strlcpy(node, "???", nodelen); if (service) strlcpy(service, "???", servicelen); } return rc; } #if defined(HAVE_UNIX_SOCKETS) /* ------- * getaddrinfo_unix - get unix socket info using IPv6-compatible API * * Bugs: only one addrinfo is set even though hintsp is NULL or * ai_socktype is 0 * AI_CANONNAME is not supported. * ------- */ static int getaddrinfo_unix(const char *path, const struct addrinfo *hintsp, struct addrinfo **result) { struct addrinfo hints; struct addrinfo *aip; struct sockaddr_un *unp; *result = NULL; MemSet(&hints, 0, sizeof(hints)); if (strlen(path) >= sizeof(unp->sun_path)) return EAI_FAIL; if (hintsp == NULL) { hints.ai_family = AF_UNIX; hints.ai_socktype = SOCK_STREAM; } else memcpy(&hints, hintsp, sizeof(hints)); if (hints.ai_socktype == 0) hints.ai_socktype = SOCK_STREAM; if (hints.ai_family != AF_UNIX) { /* shouldn't have been called */ return EAI_FAIL; } aip = calloc(1, sizeof(struct addrinfo)); if (aip == NULL) return EAI_MEMORY; unp = calloc(1, sizeof(struct sockaddr_un)); if (unp == NULL) { free(aip); return EAI_MEMORY; } aip->ai_family = AF_UNIX; aip->ai_socktype = hints.ai_socktype; aip->ai_protocol = hints.ai_protocol; aip->ai_next = NULL; aip->ai_canonname = NULL; *result = aip; unp->sun_family = AF_UNIX; aip->ai_addr = (struct sockaddr *) unp; aip->ai_addrlen = sizeof(struct sockaddr_un); strcpy(unp->sun_path, path); /* * If the supplied path starts with @, replace that with a zero byte for * the internal representation. In that mode, the entire sun_path is the * address, including trailing zero bytes. But we set the address length * to only include the length of the original string. That way the * trailing zero bytes won't show up in any network or socket lists of the * operating system. This is just a convention, also followed by other * packages. */ if (path[0] == '@') { unp->sun_path[0] = '\0'; aip->ai_addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(path); } #ifdef HAVE_STRUCT_SOCKADDR_STORAGE_SS_LEN unp->sun_len = sizeof(struct sockaddr_un); #endif return 0; } /* * Convert an address to a hostname. */ static int getnameinfo_unix(const struct sockaddr_un *sa, int salen, char *node, int nodelen, char *service, int servicelen, int flags) { int ret; /* Invalid arguments. */ if (sa == NULL || sa->sun_family != AF_UNIX || (node == NULL && service == NULL)) return EAI_FAIL; if (node) { ret = snprintf(node, nodelen, "%s", "[local]"); if (ret < 0 || ret >= nodelen) return EAI_MEMORY; } if (service) { /* * Check whether it looks like an abstract socket, but it could also * just be an empty string. */ if (sa->sun_path[0] == '\0' && sa->sun_path[1] != '\0') ret = snprintf(service, servicelen, "@%s", sa->sun_path + 1); else ret = snprintf(service, servicelen, "%s", sa->sun_path); if (ret < 0 || ret >= servicelen) return EAI_MEMORY; } return 0; } #endif /* HAVE_UNIX_SOCKETS */