/* Copyright (c) 2003-2004, Roger Dingledine * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. * Copyright (c) 2007-2019, The Tor Project, Inc. */ /* See LICENSE for licensing information */ /** * \file address.c * \brief Functions to use and manipulate the tor_addr_t structure. * * This module doesn't have any support for the libc resolver: that is all in * resolve.c. **/ #define ADDRESS_PRIVATE #include "orconfig.h" #ifdef _WIN32 /* For access to structs needed by GetAdaptersAddresses */ #ifndef WIN32_LEAN_AND_MEAN #error "orconfig.h didn't define WIN32_LEAN_AND_MEAN" #endif #ifndef WINVER #error "orconfig.h didn't define WINVER" #endif #ifndef _WIN32_WINNT #error "orconfig.h didn't define _WIN32_WINNT" #endif #if WINVER < 0x0501 #error "winver too low" #endif #if _WIN32_WINNT < 0x0501 #error "winver too low" #endif #include #include #include #include #endif /* defined(_WIN32) */ #include "lib/net/address.h" #include "lib/net/socket.h" #include "lib/cc/ctassert.h" #include "lib/container/smartlist.h" #include "lib/ctime/di_ops.h" #include "lib/log/log.h" #include "lib/log/escape.h" #include "lib/malloc/malloc.h" #include "lib/net/inaddr.h" #include "lib/string/compat_ctype.h" #include "lib/string/compat_string.h" #include "lib/string/parse_int.h" #include "lib/string/printf.h" #include "lib/string/util_string.h" #include "ext/siphash.h" #ifdef HAVE_SYS_TIME_H #include #endif #ifdef HAVE_UNISTD_H #include #endif #ifdef HAVE_ERRNO_H #include #endif #ifdef HAVE_ARPA_INET_H #include #endif #ifdef HAVE_SYS_SOCKET_H #include #endif #ifdef HAVE_NETDB_H #include #endif #ifdef HAVE_SYS_PARAM_H #include /* FreeBSD needs this to know what version it is */ #endif #ifdef HAVE_SYS_UN_H #include #endif #ifdef HAVE_IFADDRS_H #include #endif #ifdef HAVE_SYS_IOCTL_H #include #endif #ifdef HAVE_NET_IF_H #include #endif #include #include #include #include /* tor_addr_is_null() and maybe other functions rely on AF_UNSPEC being 0 to * work correctly. Bail out here if we've found a platform where AF_UNSPEC * isn't 0. */ #if AF_UNSPEC != 0 #error We rely on AF_UNSPEC being 0. Let us know about your platform, please! #endif CTASSERT(AF_UNSPEC == 0); /** Convert the tor_addr_t in a, with port in port, into a * sockaddr object in *sa_out of object size len. If not enough * room is available in sa_out, or on error, return 0. On success, return * the length of the sockaddr. * * Interface note: ordinarily, we return -1 for error. We can't do that here, * since socklen_t is unsigned on some platforms. **/ socklen_t tor_addr_to_sockaddr(const tor_addr_t *a, uint16_t port, struct sockaddr *sa_out, socklen_t len) { memset(sa_out, 0, len); sa_family_t family = tor_addr_family(a); if (family == AF_INET) { struct sockaddr_in *sin; if (len < (int)sizeof(struct sockaddr_in)) return 0; sin = (struct sockaddr_in *)sa_out; #ifdef HAVE_STRUCT_SOCKADDR_IN_SIN_LEN sin->sin_len = sizeof(struct sockaddr_in); #endif sin->sin_family = AF_INET; sin->sin_port = htons(port); sin->sin_addr.s_addr = tor_addr_to_ipv4n(a); return sizeof(struct sockaddr_in); } else if (family == AF_INET6) { struct sockaddr_in6 *sin6; if (len < (int)sizeof(struct sockaddr_in6)) return 0; sin6 = (struct sockaddr_in6 *)sa_out; #ifdef HAVE_STRUCT_SOCKADDR_IN6_SIN6_LEN sin6->sin6_len = sizeof(struct sockaddr_in6); #endif sin6->sin6_family = AF_INET6; sin6->sin6_port = htons(port); memcpy(&sin6->sin6_addr, tor_addr_to_in6_assert(a), sizeof(struct in6_addr)); return sizeof(struct sockaddr_in6); } else { return 0; } } /** Set address a to zero. This address belongs to * the AF_UNIX family. */ static void tor_addr_make_af_unix(tor_addr_t *a) { memset(a, 0, sizeof(*a)); a->family = AF_UNIX; } /** Set the tor_addr_t in a to contain the socket address contained in * sa. IF port_out is non-NULL and sa contains a port, * set *port_out to that port. Return 0 on success and -1 on * failure. */ int tor_addr_from_sockaddr(tor_addr_t *a, const struct sockaddr *sa, uint16_t *port_out) { tor_assert(a); tor_assert(sa); /* This memset is redundant; leaving it in to avoid any future accidents, however. */ memset(a, 0, sizeof(*a)); if (sa->sa_family == AF_INET) { struct sockaddr_in *sin = (struct sockaddr_in *) sa; tor_addr_from_ipv4n(a, sin->sin_addr.s_addr); if (port_out) *port_out = ntohs(sin->sin_port); } else if (sa->sa_family == AF_INET6) { struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) sa; tor_addr_from_in6(a, &sin6->sin6_addr); if (port_out) *port_out = ntohs(sin6->sin6_port); } else if (sa->sa_family == AF_UNIX) { tor_addr_make_af_unix(a); return 0; } else { tor_addr_make_unspec(a); return -1; } return 0; } /** Return a newly allocated string holding the address described in * sa. AF_UNIX, AF_UNSPEC, AF_INET, and AF_INET6 are supported. */ char * tor_sockaddr_to_str(const struct sockaddr *sa) { char address[TOR_ADDR_BUF_LEN]; char *result; tor_addr_t addr; uint16_t port; #ifdef HAVE_SYS_UN_H if (sa->sa_family == AF_UNIX) { struct sockaddr_un *s_un = (struct sockaddr_un *)sa; tor_asprintf(&result, "unix:%s", s_un->sun_path); return result; } #endif /* defined(HAVE_SYS_UN_H) */ if (sa->sa_family == AF_UNSPEC) return tor_strdup("unspec"); if (tor_addr_from_sockaddr(&addr, sa, &port) < 0) return NULL; if (! tor_addr_to_str(address, &addr, sizeof(address), 1)) return NULL; tor_asprintf(&result, "%s:%d", address, (int)port); return result; } /** Set address a to the unspecified address. This address belongs to * no family. */ void tor_addr_make_unspec(tor_addr_t *a) { memset(a, 0, sizeof(*a)); a->family = AF_UNSPEC; } /** Set address a to the null address in address family family. * The null address for AF_INET is 0.0.0.0. The null address for AF_INET6 is * [::]. AF_UNSPEC is all null. */ void tor_addr_make_null(tor_addr_t *a, sa_family_t family) { memset(a, 0, sizeof(*a)); a->family = family; } /** Return true iff ip is an IP reserved to localhost or local networks. * * If ip is in RFC1918 or RFC4193 or RFC4291, we will return true. * (fec0::/10, deprecated by RFC3879, is also treated as internal for now * and will return true.) * * If ip is 0.0.0.0 or 100.64.0.0/10 (RFC6598), we will act as: * - Internal if for_listening is 0, as these addresses are not * routable on the internet and we won't be publicly accessible to clients. * - External if for_listening is 1, as clients could connect to us * from the internet (in the case of 0.0.0.0) or a service provider's * internal network (in the case of RFC6598). */ int tor_addr_is_internal_(const tor_addr_t *addr, int for_listening, const char *filename, int lineno) { uint32_t iph4 = 0; uint32_t iph6[4]; tor_assert(addr); sa_family_t v_family = tor_addr_family(addr); if (v_family == AF_INET) { iph4 = tor_addr_to_ipv4h(addr); } else if (v_family == AF_INET6) { if (tor_addr_is_v4(addr)) { /* v4-mapped */ uint32_t *addr32 = NULL; v_family = AF_INET; // Work around an incorrect NULL pointer dereference warning in // "clang --analyze" due to limited analysis depth addr32 = tor_addr_to_in6_addr32(addr); // To improve performance, wrap this assertion in: // #if !defined(__clang_analyzer__) || PARANOIA tor_assert(addr32); iph4 = ntohl(addr32[3]); } } if (v_family == AF_INET6) { const uint32_t *a32 = tor_addr_to_in6_addr32(addr); iph6[0] = ntohl(a32[0]); iph6[1] = ntohl(a32[1]); iph6[2] = ntohl(a32[2]); iph6[3] = ntohl(a32[3]); if (for_listening && !iph6[0] && !iph6[1] && !iph6[2] && !iph6[3]) /* :: */ return 0; if (((iph6[0] & 0xfe000000) == 0xfc000000) || /* fc00/7 - RFC4193 */ ((iph6[0] & 0xffc00000) == 0xfe800000) || /* fe80/10 - RFC4291 */ ((iph6[0] & 0xffc00000) == 0xfec00000)) /* fec0/10 D- RFC3879 */ return 1; if (!iph6[0] && !iph6[1] && !iph6[2] && ((iph6[3] & 0xfffffffe) == 0x00000000)) /* ::/127 */ return 1; return 0; } else if (v_family == AF_INET) { /* special case for binding to 0.0.0.0 or 100.64/10 (RFC6598) */ if (for_listening && (!iph4 || ((iph4 & 0xffc00000) == 0x64400000))) return 0; if (((iph4 & 0xff000000) == 0x0a000000) || /* 10/8 */ ((iph4 & 0xff000000) == 0x00000000) || /* 0/8 */ ((iph4 & 0xff000000) == 0x7f000000) || /* 127/8 */ ((iph4 & 0xffc00000) == 0x64400000) || /* 100.64/10 */ ((iph4 & 0xffff0000) == 0xa9fe0000) || /* 169.254/16 */ ((iph4 & 0xfff00000) == 0xac100000) || /* 172.16/12 */ ((iph4 & 0xffff0000) == 0xc0a80000)) /* 192.168/16 */ return 1; return 0; } /* unknown address family... assume it's not safe for external use */ /* rather than tor_assert(0) */ log_warn(LD_BUG, "tor_addr_is_internal() called from %s:%d with a " "non-IP address of type %d", filename, lineno, (int)v_family); tor_fragile_assert(); return 1; } /** Convert a tor_addr_t addr into a string, and store it in * dest of size len. Returns a pointer to dest on success, * or NULL on failure. If decorate, surround IPv6 addresses with * brackets. */ const char * tor_addr_to_str(char *dest, const tor_addr_t *addr, size_t len, int decorate) { const char *ptr; tor_assert(addr && dest); switch (tor_addr_family(addr)) { case AF_INET: /* Shortest addr x.x.x.x + \0 */ if (len < 8) return NULL; ptr = tor_inet_ntop(AF_INET, &addr->addr.in_addr, dest, len); break; case AF_INET6: /* Shortest addr [ :: ] + \0 */ if (len < (3u + (decorate ? 2 : 0))) return NULL; if (decorate) ptr = tor_inet_ntop(AF_INET6, &addr->addr.in6_addr, dest+1, len-2); else ptr = tor_inet_ntop(AF_INET6, &addr->addr.in6_addr, dest, len); if (ptr && decorate) { *dest = '['; memcpy(dest+strlen(dest), "]", 2); tor_assert(ptr == dest+1); ptr = dest; } break; case AF_UNIX: tor_snprintf(dest, len, "AF_UNIX"); ptr = dest; break; default: return NULL; } return ptr; } /** Parse an .in-addr.arpa or .ip6.arpa address from address. Return 0 * if this is not an .in-addr.arpa address or an .ip6.arpa address. Return -1 * if this is an ill-formed .in-addr.arpa address or an .ip6.arpa address. * Also return -1 if family is not AF_UNSPEC, and the parsed address * family does not match family. On success, return 1, and store the * result, if any, into result, if provided. * * If accept_regular is set and the address is in neither recognized * reverse lookup hostname format, try parsing the address as a regular * IPv4 or IPv6 address too. */ int tor_addr_parse_PTR_name(tor_addr_t *result, const char *address, int family, int accept_regular) { if (!strcasecmpend(address, ".in-addr.arpa")) { /* We have an in-addr.arpa address. */ char buf[INET_NTOA_BUF_LEN]; size_t len; struct in_addr inaddr; if (family == AF_INET6) return -1; len = strlen(address) - strlen(".in-addr.arpa"); if (len >= INET_NTOA_BUF_LEN) return -1; /* Too long. */ memcpy(buf, address, len); buf[len] = '\0'; if (tor_inet_aton(buf, &inaddr) == 0) return -1; /* malformed. */ /* reverse the bytes */ inaddr.s_addr = (uint32_t) (((inaddr.s_addr & 0x000000ff) << 24) |((inaddr.s_addr & 0x0000ff00) << 8) |((inaddr.s_addr & 0x00ff0000) >> 8) |((inaddr.s_addr & 0xff000000) >> 24)); if (result) { tor_addr_from_in(result, &inaddr); } return 1; } if (!strcasecmpend(address, ".ip6.arpa")) { const char *cp; int n0, n1; struct in6_addr in6; if (family == AF_INET) return -1; cp = address; for (int i = 0; i < 16; ++i) { n0 = hex_decode_digit(*cp++); /* The low-order nybble appears first. */ if (*cp++ != '.') return -1; /* Then a dot. */ n1 = hex_decode_digit(*cp++); /* The high-order nybble appears first. */ if (*cp++ != '.') return -1; /* Then another dot. */ if (n0<0 || n1 < 0) /* Both nybbles must be hex. */ return -1; /* We don't check the length of the string in here. But that's okay, * since we already know that the string ends with ".ip6.arpa", and * there is no way to frameshift .ip6.arpa so it fits into the pattern * of hexdigit, period, hexdigit, period that we enforce above. */ /* Assign from low-byte to high-byte. */ in6.s6_addr[15-i] = n0 | (n1 << 4); } if (strcasecmp(cp, "ip6.arpa")) return -1; if (result) { tor_addr_from_in6(result, &in6); } return 1; } if (accept_regular) { tor_addr_t tmp; int r = tor_addr_parse(&tmp, address); if (r < 0) return 0; if (r != family && family != AF_UNSPEC) return -1; if (result) memcpy(result, &tmp, sizeof(tor_addr_t)); return 1; } return 0; } /** Convert addr to an in-addr.arpa name or a .ip6.arpa name, * and store the result in the outlen-byte buffer at * out. Returns a non-negative integer on success. * Returns -1 on failure. */ int tor_addr_to_PTR_name(char *out, size_t outlen, const tor_addr_t *addr) { tor_assert(out); tor_assert(addr); if (addr->family == AF_INET) { uint32_t a = tor_addr_to_ipv4h(addr); return tor_snprintf(out, outlen, "%d.%d.%d.%d.in-addr.arpa", (int)(uint8_t)((a )&0xff), (int)(uint8_t)((a>>8 )&0xff), (int)(uint8_t)((a>>16)&0xff), (int)(uint8_t)((a>>24)&0xff)); } else if (addr->family == AF_INET6) { int i; char *cp = out; const uint8_t *bytes = tor_addr_to_in6_addr8(addr); if (outlen < REVERSE_LOOKUP_NAME_BUF_LEN) return -1; for (i = 15; i >= 0; --i) { uint8_t byte = bytes[i]; *cp++ = "0123456789abcdef"[byte & 0x0f]; *cp++ = '.'; *cp++ = "0123456789abcdef"[byte >> 4]; *cp++ = '.'; } memcpy(cp, "ip6.arpa", 9); /* 8 characters plus NUL */ return 32 * 2 + 8; } return -1; } /** Parse a string s containing an IPv4/IPv6 address, and possibly * a mask and port or port range. Store the parsed address in * addr_out, a mask (if any) in mask_out, and port(s) (if any) * in port_min_out and port_max_out. * * The syntax is: * Address OptMask OptPortRange * Address ::= IPv4Address / "[" IPv6Address "]" / "*" * OptMask ::= "/" Integer / * OptPortRange ::= ":*" / ":" Integer / ":" Integer "-" Integer / * * - If mask, minport, or maxport are NULL, we do not want these * options to be set; treat them as an error if present. * - If the string has no mask, the mask is set to /32 (IPv4) or /128 (IPv6). * - If the string has one port, it is placed in both min and max port * variables. * - If the string has no port(s), port_(min|max)_out are set to 1 and 65535. * * Return an address family on success, or -1 if an invalid address string is * provided. * * If 'flags & TAPMP_EXTENDED_STAR' is false, then the wildcard address '*' * yield an IPv4 wildcard. * * If 'flags & TAPMP_EXTENDED_STAR' is true, then the wildcard address '*' * yields an AF_UNSPEC wildcard address, which expands to corresponding * wildcard IPv4 and IPv6 rules, and the following change is made * in the grammar above: * Address ::= IPv4Address / "[" IPv6Address "]" / "*" / "*4" / "*6" * with the new "*4" and "*6" productions creating a wildcard to match * IPv4 or IPv6 addresses. * * If 'flags & TAPMP_EXTENDED_STAR' and 'flags & TAPMP_STAR_IPV4_ONLY' are * both true, then the wildcard address '*' yields an IPv4 wildcard. * * If 'flags & TAPMP_EXTENDED_STAR' and 'flags & TAPMP_STAR_IPV6_ONLY' are * both true, then the wildcard address '*' yields an IPv6 wildcard. * * TAPMP_STAR_IPV4_ONLY and TAPMP_STAR_IPV6_ONLY are mutually exclusive. */ int tor_addr_parse_mask_ports(const char *s, unsigned flags, tor_addr_t *addr_out, maskbits_t *maskbits_out, uint16_t *port_min_out, uint16_t *port_max_out) { char *base = NULL, *address, *mask = NULL, *port = NULL, *rbracket = NULL; char *endptr; int any_flag=0, v4map=0; sa_family_t family; struct in6_addr in6_tmp; struct in_addr in_tmp = { .s_addr = 0 }; tor_assert(s); tor_assert(addr_out); /* We can either only want an IPv4 address or only want an IPv6 address, * but we can't only want IPv4 & IPv6 at the same time. */ tor_assert(!((flags & TAPMP_STAR_IPV4_ONLY) && (flags & TAPMP_STAR_IPV6_ONLY))); /** Longest possible length for an address, mask, and port-range combination. * Includes IP, [], /mask, :, ports */ #define MAX_ADDRESS_LENGTH (TOR_ADDR_BUF_LEN+2+(1+INET_NTOA_BUF_LEN)+12+1) if (strlen(s) > MAX_ADDRESS_LENGTH) { log_warn(LD_GENERAL, "Impossibly long IP %s; rejecting", escaped(s)); goto err; } base = tor_strdup(s); /* Break 'base' into separate strings. */ address = base; if (*address == '[') { /* Probably IPv6 */ address++; rbracket = strchr(address, ']'); if (!rbracket) { log_warn(LD_GENERAL, "No closing IPv6 bracket in address pattern; rejecting."); goto err; } } mask = strchr((rbracket?rbracket:address),'/'); port = strchr((mask?mask:(rbracket?rbracket:address)), ':'); if (port) *port++ = '\0'; if (mask) *mask++ = '\0'; if (rbracket) *rbracket = '\0'; if (port && mask) tor_assert(port > mask); if (mask && rbracket) tor_assert(mask > rbracket); /* Now "address" is the a.b.c.d|'*'|abcd::1 part... * "mask" is the Mask|Maskbits part... * and "port" is the *|port|min-max part. */ /* Process the address portion */ memset(addr_out, 0, sizeof(tor_addr_t)); if (!strcmp(address, "*")) { if (flags & TAPMP_EXTENDED_STAR) { if (flags & TAPMP_STAR_IPV4_ONLY) { family = AF_INET; tor_addr_from_ipv4h(addr_out, 0); } else if (flags & TAPMP_STAR_IPV6_ONLY) { static char nil_bytes[16] = { [0]=0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0 }; family = AF_INET6; tor_addr_from_ipv6_bytes(addr_out, nil_bytes); } else { family = AF_UNSPEC; tor_addr_make_unspec(addr_out); log_info(LD_GENERAL, "'%s' expands into rules which apply to all IPv4 and IPv6 " "addresses. (Use accept/reject *4:* for IPv4 or " "accept[6]/reject[6] *6:* for IPv6.)", s); } } else { family = AF_INET; tor_addr_from_ipv4h(addr_out, 0); } any_flag = 1; } else if (!strcmp(address, "*4") && (flags & TAPMP_EXTENDED_STAR)) { family = AF_INET; tor_addr_from_ipv4h(addr_out, 0); any_flag = 1; } else if (!strcmp(address, "*6") && (flags & TAPMP_EXTENDED_STAR)) { static char nil_bytes[16] = { [0]=0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0 }; family = AF_INET6; tor_addr_from_ipv6_bytes(addr_out, nil_bytes); any_flag = 1; } else if (tor_inet_pton(AF_INET6, address, &in6_tmp) > 0) { family = AF_INET6; tor_addr_from_in6(addr_out, &in6_tmp); } else if (tor_inet_pton(AF_INET, address, &in_tmp) > 0) { family = AF_INET; tor_addr_from_in(addr_out, &in_tmp); } else { log_warn(LD_GENERAL, "Malformed IP %s in address pattern; rejecting.", escaped(address)); goto err; } v4map = tor_addr_is_v4(addr_out); /* Parse mask */ if (maskbits_out) { int bits = 0; struct in_addr v4mask; if (mask) { /* the caller (tried to) specify a mask */ bits = (int) strtol(mask, &endptr, 10); if (!*endptr) { /* strtol converted everything, so it was an integer */ if ((bits<0 || bits>128) || (family == AF_INET && bits > 32)) { log_warn(LD_GENERAL, "Bad number of mask bits (%d) on address range; rejecting.", bits); goto err; } } else { /* mask might still be an address-style mask */ if (tor_inet_pton(AF_INET, mask, &v4mask) > 0) { bits = addr_mask_get_bits(ntohl(v4mask.s_addr)); if (bits < 0) { log_warn(LD_GENERAL, "IPv4-style mask %s is not a prefix address; rejecting.", escaped(mask)); goto err; } } else { /* Not IPv4; we don't do address-style IPv6 masks. */ log_warn(LD_GENERAL, "Malformed mask on address range %s; rejecting.", escaped(s)); goto err; } } if (family == AF_INET6 && v4map) { if (bits > 32 && bits < 96) { /* Crazy */ log_warn(LD_GENERAL, "Bad mask bits %d for V4-mapped V6 address; rejecting.", bits); goto err; } /* XXXX_IP6 is this really what we want? */ bits = 96 + bits%32; /* map v4-mapped masks onto 96-128 bits */ } if (any_flag) { log_warn(LD_GENERAL, "Found bit prefix with wildcard address; rejecting"); goto err; } } else { /* pick an appropriate mask, as none was given */ if (any_flag) bits = 0; /* This is okay whether it's V6 or V4 (FIX V4-mapped V6!) */ else if (tor_addr_family(addr_out) == AF_INET) bits = 32; else if (tor_addr_family(addr_out) == AF_INET6) bits = 128; } *maskbits_out = (maskbits_t) bits; } else { if (mask) { log_warn(LD_GENERAL, "Unexpected mask in address %s; rejecting", escaped(s)); goto err; } } /* Parse port(s) */ if (port_min_out) { uint16_t port2; if (!port_max_out) /* caller specified one port; fake the second one */ port_max_out = &port2; if (parse_port_range(port, port_min_out, port_max_out) < 0) { goto err; } else if ((*port_min_out != *port_max_out) && port_max_out == &port2) { log_warn(LD_GENERAL, "Wanted one port from address range, but there are two."); port_max_out = NULL; /* caller specified one port, so set this back */ goto err; } } else { if (port) { log_warn(LD_GENERAL, "Unexpected ports in address %s; rejecting", escaped(s)); goto err; } } tor_free(base); return tor_addr_family(addr_out); err: tor_free(base); return -1; } /** Determine whether an address is IPv4, either native or IPv4-mapped IPv6. * Note that this is about representation only, as any decent stack will * reject IPv4-mapped addresses received on the wire (and won't use them * on the wire either). */ int tor_addr_is_v4(const tor_addr_t *addr) { tor_assert(addr); if (tor_addr_family(addr) == AF_INET) return 1; if (tor_addr_family(addr) == AF_INET6) { /* First two don't need to be ordered */ uint32_t *a32 = tor_addr_to_in6_addr32(addr); if (a32[0] == 0 && a32[1] == 0 && ntohl(a32[2]) == 0x0000ffffu) return 1; } return 0; /* Not IPv4 - unknown family or a full-blood IPv6 address */ } /** Determine whether an address addr is null, either all zeroes or * belonging to family AF_UNSPEC. */ int tor_addr_is_null(const tor_addr_t *addr) { tor_assert(addr); switch (tor_addr_family(addr)) { case AF_INET6: { uint32_t *a32 = tor_addr_to_in6_addr32(addr); return (a32[0] == 0) && (a32[1] == 0) && (a32[2] == 0) && (a32[3] == 0); } case AF_INET: return (tor_addr_to_ipv4n(addr) == 0); case AF_UNIX: return 1; case AF_UNSPEC: return 1; default: log_warn(LD_BUG, "Called with unknown address family %d", (int)tor_addr_family(addr)); return 0; } //return 1; } /** Return true iff addr is a loopback address */ int tor_addr_is_loopback(const tor_addr_t *addr) { tor_assert(addr); switch (tor_addr_family(addr)) { case AF_INET6: { /* ::1 */ uint32_t *a32 = tor_addr_to_in6_addr32(addr); return (a32[0] == 0) && (a32[1] == 0) && (a32[2] == 0) && (ntohl(a32[3]) == 1); } case AF_INET: /* 127.0.0.1 */ return (tor_addr_to_ipv4h(addr) & 0xff000000) == 0x7f000000; case AF_UNSPEC: return 0; /* LCOV_EXCL_START */ default: tor_fragile_assert(); return 0; /* LCOV_EXCL_STOP */ } } /* Is addr valid? * Checks that addr is non-NULL and not tor_addr_is_null(). * If for_listening is true, IPv4 addr 0.0.0.0 is allowed. * It means "bind to all addresses on the local machine". */ int tor_addr_is_valid(const tor_addr_t *addr, int for_listening) { /* NULL addresses are invalid regardless of for_listening */ if (addr == NULL) { return 0; } /* Only allow IPv4 0.0.0.0 for_listening. */ if (for_listening && addr->family == AF_INET && tor_addr_to_ipv4h(addr) == 0) { return 1; } /* Otherwise, the address is valid if it's not tor_addr_is_null() */ return !tor_addr_is_null(addr); } /* Is the network-order IPv4 address v4n_addr valid? * Checks that addr is not zero. * Except if for_listening is true, where IPv4 addr 0.0.0.0 is allowed. */ int tor_addr_is_valid_ipv4n(uint32_t v4n_addr, int for_listening) { /* Any IPv4 address is valid with for_listening. */ if (for_listening) { return 1; } /* Otherwise, zero addresses are invalid. */ return v4n_addr != 0; } /* Is port valid? * Checks that port is not 0. * Except if for_listening is true, where port 0 is allowed. * It means "OS chooses a port". */ int tor_port_is_valid(uint16_t port, int for_listening) { /* Any port value is valid with for_listening. */ if (for_listening) { return 1; } /* Otherwise, zero ports are invalid. */ return port != 0; } /** Set dest to equal the IPv4 address in v4addr (given in * network order). */ void tor_addr_from_ipv4n(tor_addr_t *dest, uint32_t v4addr) { tor_assert(dest); memset(dest, 0, sizeof(tor_addr_t)); dest->family = AF_INET; dest->addr.in_addr.s_addr = v4addr; } /** Set dest to equal the IPv6 address in the 16 bytes at * ipv6_bytes. */ void tor_addr_from_ipv6_bytes(tor_addr_t *dest, const char *ipv6_bytes) { tor_assert(dest); tor_assert(ipv6_bytes); memset(dest, 0, sizeof(tor_addr_t)); dest->family = AF_INET6; memcpy(dest->addr.in6_addr.s6_addr, ipv6_bytes, 16); } /** Set dest equal to the IPv6 address in the in6_addr in6. */ void tor_addr_from_in6(tor_addr_t *dest, const struct in6_addr *in6) { tor_addr_from_ipv6_bytes(dest, (const char*)in6->s6_addr); } /** Copy a tor_addr_t from src to dest. */ void tor_addr_copy(tor_addr_t *dest, const tor_addr_t *src) { if (src == dest) return; tor_assert(src); tor_assert(dest); memcpy(dest, src, sizeof(tor_addr_t)); } /** Copy a tor_addr_t from src to dest, taking extra care to * copy only the well-defined portions. Used for computing hashes of * addresses. */ void tor_addr_copy_tight(tor_addr_t *dest, const tor_addr_t *src) { tor_assert(src != dest); tor_assert(src); tor_assert(dest); memset(dest, 0, sizeof(tor_addr_t)); dest->family = src->family; switch (tor_addr_family(src)) { case AF_INET: dest->addr.in_addr.s_addr = src->addr.in_addr.s_addr; break; case AF_INET6: memcpy(dest->addr.in6_addr.s6_addr, src->addr.in6_addr.s6_addr, 16); case AF_UNSPEC: break; // LCOV_EXCL_START default: tor_fragile_assert(); // LCOV_EXCL_STOP } } /** Given two addresses addr1 and addr2, return 0 if the two * addresses are equivalent under the mask mbits, less than 0 if addr1 * precedes addr2, and greater than 0 otherwise. * * Different address families (IPv4 vs IPv6) are always considered unequal if * how is CMP_EXACT; otherwise, IPv6-mapped IPv4 addresses are * considered equivalent to their IPv4 equivalents. * * As a special case, all pointer-wise distinct AF_UNIX addresses are always * considered unequal since tor_addr_t currently does not contain the * information required to make the comparison. */ int tor_addr_compare(const tor_addr_t *addr1, const tor_addr_t *addr2, tor_addr_comparison_t how) { return tor_addr_compare_masked(addr1, addr2, 128, how); } /** As tor_addr_compare(), but only looks at the first mask bits of * the address. * * Reduce over-specific masks (>128 for ipv6, >32 for ipv4) to 128 or 32. * * The mask is interpreted relative to addr1, so that if a is * \::ffff:1.2.3.4, and b is 3.4.5.6, * tor_addr_compare_masked(a,b,100,CMP_SEMANTIC) is the same as * -tor_addr_compare_masked(b,a,4,CMP_SEMANTIC). * * We guarantee that the ordering from tor_addr_compare_masked is a total * order on addresses, but not that it is any particular order, or that it * will be the same from one version to the next. */ int tor_addr_compare_masked(const tor_addr_t *addr1, const tor_addr_t *addr2, maskbits_t mbits, tor_addr_comparison_t how) { /** Helper: Evaluates to -1 if a is less than b, 0 if a equals b, or 1 if a * is greater than b. May evaluate a and b more than once. */ #define TRISTATE(a,b) (((a)<(b))?-1: (((a)==(b))?0:1)) sa_family_t family1, family2, v_family1, v_family2; tor_assert(addr1 && addr2); v_family1 = family1 = tor_addr_family(addr1); v_family2 = family2 = tor_addr_family(addr2); if (family1==family2) { /* When the families are the same, there's only one way to do the * comparison: exactly. */ int r; switch (family1) { case AF_UNSPEC: return 0; /* All unspecified addresses are equal */ case AF_INET: { uint32_t a1 = tor_addr_to_ipv4h(addr1); uint32_t a2 = tor_addr_to_ipv4h(addr2); if (mbits <= 0) return 0; if (mbits > 32) mbits = 32; a1 >>= (32-mbits); a2 >>= (32-mbits); r = TRISTATE(a1, a2); return r; } case AF_INET6: { if (mbits > 128) mbits = 128; const uint8_t *a1 = tor_addr_to_in6_addr8(addr1); const uint8_t *a2 = tor_addr_to_in6_addr8(addr2); const int bytes = mbits >> 3; const int leftover_bits = mbits & 7; if (bytes && (r = tor_memcmp(a1, a2, bytes))) { return r; } else if (leftover_bits) { uint8_t b1 = a1[bytes] >> (8-leftover_bits); uint8_t b2 = a2[bytes] >> (8-leftover_bits); return TRISTATE(b1, b2); } else { return 0; } } case AF_UNIX: /* HACKHACKHACKHACKHACK: * tor_addr_t doesn't contain a copy of sun_path, so it's not * possible to compare this at all. * * Since the only time we currently actually should be comparing * 2 AF_UNIX addresses is when dealing with ISO_CLIENTADDR (which * is disabled for AF_UNIX SocksPorts anyway), this just does * a pointer comparison. * * See: #20261. */ if (addr1 < addr2) return -1; else if (addr1 == addr2) return 0; else return 1; /* LCOV_EXCL_START */ default: tor_fragile_assert(); return 0; /* LCOV_EXCL_STOP */ } } else if (how == CMP_EXACT) { /* Unequal families and an exact comparison? Stop now! */ return TRISTATE(family1, family2); } if (mbits == 0) return 0; if (family1 == AF_INET6 && tor_addr_is_v4(addr1)) v_family1 = AF_INET; if (family2 == AF_INET6 && tor_addr_is_v4(addr2)) v_family2 = AF_INET; if (v_family1 == v_family2) { /* One or both addresses are a mapped ipv4 address. */ uint32_t a1, a2; if (family1 == AF_INET6) { a1 = tor_addr_to_mapped_ipv4h(addr1); if (mbits <= 96) return 0; mbits -= 96; /* We just decided that the first 96 bits of a1 "match". */ } else { a1 = tor_addr_to_ipv4h(addr1); } if (family2 == AF_INET6) { a2 = tor_addr_to_mapped_ipv4h(addr2); } else { a2 = tor_addr_to_ipv4h(addr2); } if (mbits > 32) mbits = 32; a1 >>= (32-mbits); a2 >>= (32-mbits); return TRISTATE(a1, a2); } else { /* Unequal families, and semantic comparison, and no semantic family * matches. */ return TRISTATE(family1, family2); } } /** Input for siphash, to produce some output for an unspec value. */ static const uint32_t unspec_hash_input[] = { 0x4e4df09f, 0x92985342 }; /** Return a hash code based on the address addr. DOCDOC extra */ uint64_t tor_addr_hash(const tor_addr_t *addr) { switch (tor_addr_family(addr)) { case AF_INET: return siphash24g(&addr->addr.in_addr.s_addr, 4); case AF_UNSPEC: return siphash24g(unspec_hash_input, sizeof(unspec_hash_input)); case AF_INET6: return siphash24g(&addr->addr.in6_addr.s6_addr, 16); /* LCOV_EXCL_START */ default: tor_fragile_assert(); return 0; /* LCOV_EXCL_STOP */ } } /** As tor_addr_hash, but use a particular siphash key. */ uint64_t tor_addr_keyed_hash(const struct sipkey *key, const tor_addr_t *addr) { /* This is duplicate code with tor_addr_hash, since this function needs to * be backportable all the way to 0.2.9. */ switch (tor_addr_family(addr)) { case AF_INET: return siphash24(&addr->addr.in_addr.s_addr, 4, key); case AF_UNSPEC: return siphash24(unspec_hash_input, sizeof(unspec_hash_input), key); case AF_INET6: return siphash24(&addr->addr.in6_addr.s6_addr, 16, key); default: /* LCOV_EXCL_START */ tor_fragile_assert(); return 0; /* LCOV_EXCL_STOP */ } } /** Return a newly allocated string with a representation of addr. */ char * tor_addr_to_str_dup(const tor_addr_t *addr) { char buf[TOR_ADDR_BUF_LEN]; if (tor_addr_to_str(buf, addr, sizeof(buf), 0)) { return tor_strdup(buf); } else { return tor_strdup(""); } } /** Return a string representing the address addr. This string * is statically allocated, and must not be freed. Each call to * fmt_addr_impl invalidates the last result of the function. * This function is not thread-safe. If decorate is set, add * brackets to IPv6 addresses. * * It's better to use the wrapper macros of this function: * fmt_addr() and fmt_and_decorate_addr(). */ const char * fmt_addr_impl(const tor_addr_t *addr, int decorate) { static char buf[TOR_ADDR_BUF_LEN]; if (!addr) return ""; if (tor_addr_to_str(buf, addr, sizeof(buf), decorate)) return buf; else return "???"; } /** Return a string representing the pair addr and port. * This calls fmt_and_decorate_addr internally, so IPv6 addresses will * have brackets, and the caveats of fmt_addr_impl apply. */ const char * fmt_addrport(const tor_addr_t *addr, uint16_t port) { /* Add space for a colon and up to 5 digits. */ static char buf[TOR_ADDR_BUF_LEN + 6]; tor_snprintf(buf, sizeof(buf), "%s:%u", fmt_and_decorate_addr(addr), port); return buf; } /** Like fmt_addr(), but takes addr as a host-order IPv4 * addresses. Also not thread-safe, also clobbers its return buffer on * repeated calls. */ const char * fmt_addr32(uint32_t addr) { static char buf[INET_NTOA_BUF_LEN]; struct in_addr in; in.s_addr = htonl(addr); tor_inet_ntoa(&in, buf, sizeof(buf)); return buf; } /** Convert the string in src to a tor_addr_t addr. The string * may be an IPv4 address, an IPv6 address, or an IPv6 address surrounded by * square brackets. * * Return an address family on success, or -1 if an invalid address string is * provided. */ int tor_addr_parse(tor_addr_t *addr, const char *src) { /* Holds substring of IPv6 address after removing square brackets */ char *tmp = NULL; int result; struct in_addr in_tmp; struct in6_addr in6_tmp; int brackets_detected = 0; tor_assert(addr && src); size_t len = strlen(src); if (len && src[0] == '[' && src[len - 1] == ']') { brackets_detected = 1; src = tmp = tor_strndup(src+1, strlen(src)-2); } if (tor_inet_pton(AF_INET6, src, &in6_tmp) > 0) { result = AF_INET6; tor_addr_from_in6(addr, &in6_tmp); } else if (!brackets_detected && tor_inet_pton(AF_INET, src, &in_tmp) > 0) { result = AF_INET; tor_addr_from_in(addr, &in_tmp); } else { result = -1; } tor_free(tmp); return result; } #ifdef HAVE_IFADDRS_TO_SMARTLIST /* * Convert a linked list consisting of ifaddrs structures * into smartlist of tor_addr_t structures. */ STATIC smartlist_t * ifaddrs_to_smartlist(const struct ifaddrs *ifa, sa_family_t family) { smartlist_t *result = smartlist_new(); const struct ifaddrs *i; for (i = ifa; i; i = i->ifa_next) { tor_addr_t tmp; if ((i->ifa_flags & (IFF_UP | IFF_RUNNING)) != (IFF_UP | IFF_RUNNING)) continue; if (!i->ifa_addr) continue; if (i->ifa_addr->sa_family != AF_INET && i->ifa_addr->sa_family != AF_INET6) continue; if (family != AF_UNSPEC && i->ifa_addr->sa_family != family) continue; if (tor_addr_from_sockaddr(&tmp, i->ifa_addr, NULL) < 0) continue; smartlist_add(result, tor_memdup(&tmp, sizeof(tmp))); } return result; } /** Use getiffaddrs() function to get list of current machine * network interface addresses. Represent the result by smartlist of * tor_addr_t structures. */ STATIC smartlist_t * get_interface_addresses_ifaddrs(int severity, sa_family_t family) { /* Most free Unixy systems provide getifaddrs, which gives us a linked list * of struct ifaddrs. */ struct ifaddrs *ifa = NULL; smartlist_t *result; if (getifaddrs(&ifa) < 0) { log_fn(severity, LD_NET, "Unable to call getifaddrs(): %s", strerror(errno)); return NULL; } result = ifaddrs_to_smartlist(ifa, family); freeifaddrs(ifa); return result; } #endif /* defined(HAVE_IFADDRS_TO_SMARTLIST) */ #ifdef HAVE_IP_ADAPTER_TO_SMARTLIST /** Convert a Windows-specific addresses linked list into smartlist * of tor_addr_t structures. */ STATIC smartlist_t * ip_adapter_addresses_to_smartlist(const IP_ADAPTER_ADDRESSES *addresses) { smartlist_t *result = smartlist_new(); const IP_ADAPTER_ADDRESSES *address; for (address = addresses; address; address = address->Next) { const IP_ADAPTER_UNICAST_ADDRESS *a; for (a = address->FirstUnicastAddress; a; a = a->Next) { /* Yes, it's a linked list inside a linked list */ const struct sockaddr *sa = a->Address.lpSockaddr; tor_addr_t tmp; if (sa->sa_family != AF_INET && sa->sa_family != AF_INET6) continue; if (tor_addr_from_sockaddr(&tmp, sa, NULL) < 0) continue; smartlist_add(result, tor_memdup(&tmp, sizeof(tmp))); } } return result; } /** Windows only: use GetAdaptersAddresses() to retrieve the network interface * addresses of the current machine. * Returns a smartlist of tor_addr_t structures. */ STATIC smartlist_t * get_interface_addresses_win32(int severity, sa_family_t family) { smartlist_t *result = NULL; ULONG size, res; IP_ADAPTER_ADDRESSES *addresses = NULL; (void) severity; #define FLAGS (GAA_FLAG_SKIP_ANYCAST | \ GAA_FLAG_SKIP_MULTICAST | \ GAA_FLAG_SKIP_DNS_SERVER) /* Guess how much space we need. */ size = 15*1024; addresses = tor_malloc(size); /* Exists in windows XP and later. */ res = GetAdaptersAddresses(family, FLAGS, NULL, addresses, &size); if (res == ERROR_BUFFER_OVERFLOW) { /* we didn't guess that we needed enough space; try again */ tor_free(addresses); addresses = tor_malloc(size); res = GetAdaptersAddresses(AF_UNSPEC, FLAGS, NULL, addresses, &size); } if (res != NO_ERROR) { log_fn(severity, LD_NET, "GetAdaptersAddresses failed (result: %lu)", res); goto done; } result = ip_adapter_addresses_to_smartlist(addresses); done: tor_free(addresses); return result; } #endif /* defined(HAVE_IP_ADAPTER_TO_SMARTLIST) */ #ifdef HAVE_IFCONF_TO_SMARTLIST /* Guess how much space we need. There shouldn't be any struct ifreqs * larger than this, even on OS X where the struct's size is dynamic. */ #define IFREQ_SIZE 4096 /* This is defined on Mac OS X */ #ifndef _SIZEOF_ADDR_IFREQ #define _SIZEOF_ADDR_IFREQ sizeof #endif /* Free ifc->ifc_buf safely. */ static void ifconf_free_ifc_buf(struct ifconf *ifc) { /* On macOS, tor_free() takes the address of ifc.ifc_buf, which leads to * undefined behaviour, because pointer-to-pointers are expected to be * aligned at 8-bytes, but the ifconf structure is packed. So we use * raw_free() instead. */ raw_free(ifc->ifc_buf); ifc->ifc_buf = NULL; } /** Convert *buf, an ifreq structure array of size buflen, * into smartlist of tor_addr_t structures. */ STATIC smartlist_t * ifreq_to_smartlist(char *buf, size_t buflen) { smartlist_t *result = smartlist_new(); char *end = buf + buflen; /* These acrobatics are due to alignment issues which trigger * undefined behaviour traps on OSX. */ struct ifreq *r = tor_malloc(IFREQ_SIZE); while (buf < end) { /* Copy up to IFREQ_SIZE bytes into the struct ifreq, but don't overrun * buf. */ memcpy(r, buf, end - buf < IFREQ_SIZE ? end - buf : IFREQ_SIZE); const struct sockaddr *sa = &r->ifr_addr; tor_addr_t tmp; int valid_sa_family = (sa->sa_family == AF_INET || sa->sa_family == AF_INET6); int conversion_success = (tor_addr_from_sockaddr(&tmp, sa, NULL) == 0); if (valid_sa_family && conversion_success) smartlist_add(result, tor_memdup(&tmp, sizeof(tmp))); buf += _SIZEOF_ADDR_IFREQ(*r); } tor_free(r); return result; } /** Use ioctl(.,SIOCGIFCONF,.) to get a list of current machine * network interface addresses. Represent the result by smartlist of * tor_addr_t structures. */ STATIC smartlist_t * get_interface_addresses_ioctl(int severity, sa_family_t family) { /* Some older unixy systems make us use ioctl(SIOCGIFCONF) */ struct ifconf ifc; ifc.ifc_buf = NULL; int fd; smartlist_t *result = NULL; /* This interface, AFAICT, only supports AF_INET addresses, * except on AIX. For Solaris, we could use SIOCGLIFCONF. */ /* Bail out if family is neither AF_INET nor AF_UNSPEC since * ioctl() technique supports non-IPv4 interface addresses on * a small number of niche systems only. If family is AF_UNSPEC, * fall back to getting AF_INET addresses only. */ if (family == AF_UNSPEC) family = AF_INET; else if (family != AF_INET) return NULL; fd = socket(family, SOCK_DGRAM, 0); if (fd < 0) { tor_log(severity, LD_NET, "socket failed: %s", strerror(errno)); goto done; } int mult = 1; do { mult *= 2; ifc.ifc_len = mult * IFREQ_SIZE; ifc.ifc_buf = tor_realloc(ifc.ifc_buf, ifc.ifc_len); tor_assert(ifc.ifc_buf); if (ioctl(fd, SIOCGIFCONF, &ifc) < 0) { tor_log(severity, LD_NET, "ioctl failed: %s", strerror(errno)); goto done; } /* Ensure we have least IFREQ_SIZE bytes unused at the end. Otherwise, we * don't know if we got everything during ioctl. */ } while (mult * IFREQ_SIZE - ifc.ifc_len <= IFREQ_SIZE); result = ifreq_to_smartlist(ifc.ifc_buf, ifc.ifc_len); done: if (fd >= 0) close(fd); ifconf_free_ifc_buf(&ifc); return result; } #endif /* defined(HAVE_IFCONF_TO_SMARTLIST) */ /** Try to ask our network interfaces what addresses they are bound to. * Return a new smartlist of tor_addr_t on success, and NULL on failure. * (An empty smartlist indicates that we successfully learned that we have no * addresses.) Log failure messages at severity. Only return the * interface addresses of requested family and ignore the addresses * of other address families. */ MOCK_IMPL(smartlist_t *, get_interface_addresses_raw,(int severity, sa_family_t family)) { smartlist_t *result = NULL; #if defined(HAVE_IFADDRS_TO_SMARTLIST) if ((result = get_interface_addresses_ifaddrs(severity, family))) return result; #endif #if defined(HAVE_IP_ADAPTER_TO_SMARTLIST) if ((result = get_interface_addresses_win32(severity, family))) return result; #endif #if defined(HAVE_IFCONF_TO_SMARTLIST) if ((result = get_interface_addresses_ioctl(severity, family))) return result; #endif (void) severity; (void) result; return NULL; } /** Return true iff a is a multicast address. */ int tor_addr_is_multicast(const tor_addr_t *a) { sa_family_t family = tor_addr_family(a); if (family == AF_INET) { uint32_t ipv4h = tor_addr_to_ipv4h(a); if ((ipv4h >> 24) == 0xe0) return 1; /* Multicast */ } else if (family == AF_INET6) { const uint8_t *a32 = tor_addr_to_in6_addr8(a); if (a32[0] == 0xff) return 1; } return 0; } /** Attempt to retrieve IP address of current host by utilizing some * UDP socket trickery. Only look for address of given family * (only AF_INET and AF_INET6 are supported). Set result to *addr. * Return 0 on success, -1 on failure. */ MOCK_IMPL(int, get_interface_address6_via_udp_socket_hack,(int severity, sa_family_t family, tor_addr_t *addr)) { struct sockaddr_storage target_addr; int sock=-1, r=-1; socklen_t addr_len; memset(addr, 0, sizeof(tor_addr_t)); memset(&target_addr, 0, sizeof(target_addr)); /* Don't worry: no packets are sent. We just need to use a real address * on the actual Internet. */ if (family == AF_INET6) { struct sockaddr_in6 *sin6 = (struct sockaddr_in6*)&target_addr; /* Use the "discard" service port */ sin6->sin6_port = htons(9); sock = tor_open_socket(PF_INET6,SOCK_DGRAM,IPPROTO_UDP); addr_len = (socklen_t)sizeof(struct sockaddr_in6); sin6->sin6_family = AF_INET6; S6_ADDR16(sin6->sin6_addr)[0] = htons(0x2002); /* 2002:: */ } else if (family == AF_INET) { struct sockaddr_in *sin = (struct sockaddr_in*)&target_addr; /* Use the "discard" service port */ sin->sin_port = htons(9); sock = tor_open_socket(PF_INET,SOCK_DGRAM,IPPROTO_UDP); addr_len = (socklen_t)sizeof(struct sockaddr_in); sin->sin_family = AF_INET; sin->sin_addr.s_addr = htonl(0x12000001); /* 18.0.0.1 */ } else { return -1; } if (sock < 0) { int e = tor_socket_errno(-1); log_fn(severity, LD_NET, "unable to create socket: %s", tor_socket_strerror(e)); goto err; } if (tor_connect_socket(sock,(struct sockaddr *)&target_addr, addr_len) < 0) { int e = tor_socket_errno(sock); log_fn(severity, LD_NET, "connect() failed: %s", tor_socket_strerror(e)); goto err; } if (tor_addr_from_getsockname(addr, sock) < 0) { int e = tor_socket_errno(sock); log_fn(severity, LD_NET, "getsockname() to determine interface failed: %s", tor_socket_strerror(e)); goto err; } if (tor_addr_is_loopback(addr) || tor_addr_is_multicast(addr)) { log_fn(severity, LD_NET, "Address that we determined via UDP socket" " magic is unsuitable for public comms."); } else { r=0; } err: if (sock >= 0) tor_close_socket(sock); if (r == -1) memset(addr, 0, sizeof(tor_addr_t)); return r; } /** Set *addr to an arbitrary IP address (if any) of an interface that * connects to the Internet. Prefer public IP addresses to internal IP * addresses. This address should only be used in checking whether our * address has changed, as it may be an internal IP address. Return 0 on * success, -1 on failure. * Prefer get_interface_address6_list for a list of all addresses on all * interfaces which connect to the Internet. */ MOCK_IMPL(int, get_interface_address6,(int severity, sa_family_t family, tor_addr_t *addr)) { smartlist_t *addrs; int rv = -1; tor_assert(addr); memset(addr, 0, sizeof(tor_addr_t)); /* Get a list of public or internal IPs in arbitrary order */ addrs = get_interface_address6_list(severity, family, 1); /* Find the first non-internal address, or the last internal address * Ideally, we want the default route, see #12377 for details */ SMARTLIST_FOREACH_BEGIN(addrs, tor_addr_t *, a) { tor_addr_copy(addr, a); rv = 0; /* If we found a non-internal address, declare success. Otherwise, * keep looking. */ if (!tor_addr_is_internal(a, 0)) break; } SMARTLIST_FOREACH_END(a); interface_address6_list_free(addrs); return rv; } /** Free a smartlist of IP addresses returned by get_interface_address6_list. */ void interface_address6_list_free_(smartlist_t *addrs) { if (addrs != NULL) { SMARTLIST_FOREACH(addrs, tor_addr_t *, a, tor_free(a)); smartlist_free(addrs); } } /** Return a smartlist of the IP addresses of type family from all interfaces * on the server. Excludes loopback and multicast addresses. Only includes * internal addresses if include_internal is true. (Note that a relay behind * NAT may use an internal address to connect to the Internet.) * An empty smartlist means that there are no addresses of the selected type * matching these criteria. * Returns NULL on failure. * Use interface_address6_list_free to free the returned list. */ MOCK_IMPL(smartlist_t *, get_interface_address6_list,(int severity, sa_family_t family, int include_internal)) { smartlist_t *addrs; tor_addr_t addr; /* Try to do this the smart way if possible. */ if ((addrs = get_interface_addresses_raw(severity, family))) { SMARTLIST_FOREACH_BEGIN(addrs, tor_addr_t *, a) { if (tor_addr_is_loopback(a) || tor_addr_is_multicast(a)) { SMARTLIST_DEL_CURRENT_KEEPORDER(addrs, a); tor_free(a); continue; } if (!include_internal && tor_addr_is_internal(a, 0)) { SMARTLIST_DEL_CURRENT_KEEPORDER(addrs, a); tor_free(a); continue; } } SMARTLIST_FOREACH_END(a); } if (addrs && smartlist_len(addrs) > 0) { return addrs; } /* if we removed all entries as unsuitable */ if (addrs) { smartlist_free(addrs); } /* Okay, the smart way is out. */ addrs = smartlist_new(); if (family == AF_INET || family == AF_UNSPEC) { if (get_interface_address6_via_udp_socket_hack(severity,AF_INET, &addr) == 0) { if (include_internal || !tor_addr_is_internal(&addr, 0)) { smartlist_add(addrs, tor_memdup(&addr, sizeof(addr))); } } } if (family == AF_INET6 || family == AF_UNSPEC) { if (get_interface_address6_via_udp_socket_hack(severity,AF_INET6, &addr) == 0) { if (include_internal || !tor_addr_is_internal(&addr, 0)) { smartlist_add(addrs, tor_memdup(&addr, sizeof(addr))); } } } return addrs; } /* ====== * IPv4 helpers * XXXX IPv6 deprecate some of these. */ /** Given an address of the form "ip:port", try to divide it into its * ip and port portions, setting *address_out to a newly * allocated string holding the address portion and *port_out * to the port. * * Don't do DNS lookups and don't allow domain names in the "ip" field. * * If default_port is less than 0, don't accept addrport of the * form "ip" or "ip:0". Otherwise, accept those forms, and set * *port_out to default_port. * * Return 0 on success, -1 on failure. */ int tor_addr_port_parse(int severity, const char *addrport, tor_addr_t *address_out, uint16_t *port_out, int default_port) { int retval = -1; int r; char *addr_tmp = NULL; tor_assert(addrport); tor_assert(address_out); tor_assert(port_out); r = tor_addr_port_split(severity, addrport, &addr_tmp, port_out); if (r < 0) goto done; if (!*port_out) { if (default_port >= 0) *port_out = default_port; else goto done; } /* make sure that address_out is an IP address */ if (tor_addr_parse(address_out, addr_tmp) < 0) goto done; retval = 0; done: tor_free(addr_tmp); return retval; } /** Given an address of the form "host[:port]", try to divide it into its host * and port portions, setting *address_out to a newly allocated string * holding the address portion and *port_out to the port (or 0 if no * port is given). Return 0 on success, -1 on failure. */ int tor_addr_port_split(int severity, const char *addrport, char **address_out, uint16_t *port_out) { tor_addr_t a_tmp; tor_assert(addrport); tor_assert(address_out); tor_assert(port_out); /* We need to check for IPv6 manually because the logic below doesn't * do a good job on IPv6 addresses that lack a port. */ if (tor_addr_parse(&a_tmp, addrport) == AF_INET6) { *port_out = 0; *address_out = tor_strdup(addrport); return 0; } const char *colon; char *address_ = NULL; int port_; int ok = 1; colon = strrchr(addrport, ':'); if (colon) { address_ = tor_strndup(addrport, colon-addrport); port_ = (int) tor_parse_long(colon+1,10,1,65535,NULL,NULL); if (!port_) { log_fn(severity, LD_GENERAL, "Port %s out of range", escaped(colon+1)); ok = 0; } if (!port_out) { char *esc_addrport = esc_for_log(addrport); log_fn(severity, LD_GENERAL, "Port %s given on %s when not required", escaped(colon+1), esc_addrport); tor_free(esc_addrport); ok = 0; } } else { address_ = tor_strdup(addrport); port_ = 0; } if (ok) { *address_out = address_; } else { *address_out = NULL; tor_free(address_); } if (port_out) *port_out = ok ? ((uint16_t) port_) : 0; return ok ? 0 : -1; } /** If mask is an address mask for a bit-prefix, return the number of * bits. Otherwise, return -1. */ int addr_mask_get_bits(uint32_t mask) { int i; if (mask == 0) return 0; if (mask == 0xFFFFFFFFu) return 32; for (i=1; i<=32; ++i) { if (mask == (uint32_t) ~((1u<<(32-i))-1)) { return i; } } return -1; } /** Parse a string s in the format of (*|port(-maxport)?)?, setting the * various *out pointers as appropriate. Return 0 on success, -1 on failure. */ int parse_port_range(const char *port, uint16_t *port_min_out, uint16_t *port_max_out) { int port_min, port_max, ok; tor_assert(port_min_out); tor_assert(port_max_out); if (!port || *port == '\0' || strcmp(port, "*") == 0) { port_min = 1; port_max = 65535; } else { char *endptr = NULL; port_min = (int)tor_parse_long(port, 10, 0, 65535, &ok, &endptr); if (!ok) { log_warn(LD_GENERAL, "Malformed port %s on address range; rejecting.", escaped(port)); return -1; } else if (endptr && *endptr == '-') { port = endptr+1; endptr = NULL; port_max = (int)tor_parse_long(port, 10, 1, 65535, &ok, &endptr); if (!ok) { log_warn(LD_GENERAL, "Malformed port %s on address range; rejecting.", escaped(port)); return -1; } } else { port_max = port_min; } if (port_min > port_max) { log_warn(LD_GENERAL, "Insane port range on address policy; rejecting."); return -1; } } if (port_min < 1) port_min = 1; if (port_max > 65535) port_max = 65535; *port_min_out = (uint16_t) port_min; *port_max_out = (uint16_t) port_max; return 0; } /** Given a host-order addr, call tor_inet_ntop() on it * and return a strdup of the resulting address. */ char * tor_dup_ip(uint32_t addr) { char buf[TOR_ADDR_BUF_LEN]; struct in_addr in; in.s_addr = htonl(addr); tor_inet_ntop(AF_INET, &in, buf, sizeof(buf)); return tor_strdup(buf); } /** * Set *addr to a host-order IPv4 address (if any) of an * interface that connects to the Internet. Prefer public IP addresses to * internal IP addresses. This address should only be used in checking * whether our address has changed, as it may be an internal IPv4 address. * Return 0 on success, -1 on failure. * Prefer get_interface_address_list6 for a list of all IPv4 and IPv6 * addresses on all interfaces which connect to the Internet. */ MOCK_IMPL(int, get_interface_address,(int severity, uint32_t *addr)) { tor_addr_t local_addr; int r; memset(addr, 0, sizeof(uint32_t)); r = get_interface_address6(severity, AF_INET, &local_addr); if (r>=0) *addr = tor_addr_to_ipv4h(&local_addr); return r; } /** Return true if we can tell that name is a canonical name for the * loopback address. Return true also for *.local hostnames, which are * multicast DNS names for hosts on the local network. */ int tor_addr_hostname_is_local(const char *name) { return !strcasecmp(name, "localhost") || !strcasecmp(name, "local") || !strcasecmpend(name, ".local"); } /** Return a newly allocated tor_addr_port_t with addr and port filled in. */ tor_addr_port_t * tor_addr_port_new(const tor_addr_t *addr, uint16_t port) { tor_addr_port_t *ap = tor_malloc_zero(sizeof(tor_addr_port_t)); if (addr) tor_addr_copy(&ap->addr, addr); ap->port = port; return ap; } /** Return true iff a and b are the same address and port */ int tor_addr_port_eq(const tor_addr_port_t *a, const tor_addr_port_t *b) { return tor_addr_eq(&a->addr, &b->addr) && a->port == b->port; } /** Return true if string represents a valid IPv4 adddress in * 'a.b.c.d' form. */ int string_is_valid_ipv4_address(const char *string) { struct in_addr addr; return (tor_inet_pton(AF_INET,string,&addr) == 1); } /** Return true if string represents a valid IPv6 address in * a form that inet_pton() can parse. */ int string_is_valid_ipv6_address(const char *string) { struct in6_addr addr; return (tor_inet_pton(AF_INET6,string,&addr) == 1); } /** Return true iff string is a valid destination address, * i.e. either a DNS hostname or IPv4/IPv6 address string. */ int string_is_valid_dest(const char *string) { char *tmp = NULL; int retval; size_t len; if (string == NULL) return 0; len = strlen(string); if (len == 0) return 0; if (string[0] == '[' && string[len - 1] == ']') string = tmp = tor_strndup(string + 1, len - 2); retval = string_is_valid_ipv4_address(string) || string_is_valid_ipv6_address(string) || string_is_valid_nonrfc_hostname(string); tor_free(tmp); return retval; } /** Return true iff string matches a pattern of DNS names * that we allow Tor clients to connect to. * * Note: This allows certain technically invalid characters ('_') to cope * with misconfigured zones that have been encountered in the wild. */ int string_is_valid_nonrfc_hostname(const char *string) { int result = 1; int has_trailing_dot; char *last_label; smartlist_t *components; if (!string || strlen(string) == 0) return 0; if (string_is_valid_ipv4_address(string)) return 0; components = smartlist_new(); smartlist_split_string(components,string,".",0,0); if (BUG(smartlist_len(components) == 0)) { // LCOV_EXCL_START should be impossible given the earlier checks. smartlist_free(components); return 0; // LCOV_EXCL_STOP } /* Allow a single terminating '.' used rarely to indicate domains * are FQDNs rather than relative. */ last_label = (char *)smartlist_get(components, smartlist_len(components) - 1); has_trailing_dot = (last_label[0] == '\0'); if (has_trailing_dot) { smartlist_pop_last(components); tor_free(last_label); last_label = NULL; } SMARTLIST_FOREACH_BEGIN(components, char *, c) { if ((c[0] == '-') || (*c == '_')) { result = 0; break; } do { result = (TOR_ISALNUM(*c) || (*c == '-') || (*c == '_')); c++; } while (result && *c); if (result == 0) { break; } } SMARTLIST_FOREACH_END(c); SMARTLIST_FOREACH_BEGIN(components, char *, c) { tor_free(c); } SMARTLIST_FOREACH_END(c); smartlist_free(components); return result; }