diff options
Diffstat (limited to 'addr.c')
| -rw-r--r-- | addr.c | 506 |
1 files changed, 506 insertions, 0 deletions
@@ -0,0 +1,506 @@ +/* $OpenBSD: addr.c,v 1.7 2023/03/27 03:31:05 djm Exp $ */ + +/* + * Copyright (c) 2004-2008 Damien Miller <djm@mindrot.org> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include "includes.h" + +#include <sys/types.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <arpa/inet.h> + +#include <netdb.h> +#include <string.h> +#include <stdlib.h> +#include <stdio.h> + +#include "addr.h" + +#define _SA(x) ((struct sockaddr *)(x)) + +int +addr_unicast_masklen(int af) +{ + switch (af) { + case AF_INET: + return 32; + case AF_INET6: + return 128; + default: + return -1; + } +} + +static inline int +masklen_valid(int af, u_int masklen) +{ + switch (af) { + case AF_INET: + return masklen <= 32 ? 0 : -1; + case AF_INET6: + return masklen <= 128 ? 0 : -1; + default: + return -1; + } +} + +int +addr_xaddr_to_sa(const struct xaddr *xa, struct sockaddr *sa, socklen_t *len, + u_int16_t port) +{ + struct sockaddr_in *in4 = (struct sockaddr_in *)sa; + struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)sa; + + if (xa == NULL || sa == NULL || len == NULL) + return -1; + + switch (xa->af) { + case AF_INET: + if (*len < sizeof(*in4)) + return -1; + memset(sa, '\0', sizeof(*in4)); + *len = sizeof(*in4); +#ifdef SOCK_HAS_LEN + in4->sin_len = sizeof(*in4); +#endif + in4->sin_family = AF_INET; + in4->sin_port = htons(port); + memcpy(&in4->sin_addr, &xa->v4, sizeof(in4->sin_addr)); + break; + case AF_INET6: + if (*len < sizeof(*in6)) + return -1; + memset(sa, '\0', sizeof(*in6)); + *len = sizeof(*in6); +#ifdef SOCK_HAS_LEN + in6->sin6_len = sizeof(*in6); +#endif + in6->sin6_family = AF_INET6; + in6->sin6_port = htons(port); + memcpy(&in6->sin6_addr, &xa->v6, sizeof(in6->sin6_addr)); +#ifdef HAVE_STRUCT_SOCKADDR_IN6_SIN6_SCOPE_ID + in6->sin6_scope_id = xa->scope_id; +#endif + break; + default: + return -1; + } + return 0; +} + +/* + * Convert struct sockaddr to struct xaddr + * Returns 0 on success, -1 on failure. + */ +int +addr_sa_to_xaddr(struct sockaddr *sa, socklen_t slen, struct xaddr *xa) +{ + struct sockaddr_in *in4 = (struct sockaddr_in *)sa; + struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)sa; + + memset(xa, '\0', sizeof(*xa)); + + switch (sa->sa_family) { + case AF_INET: + if (slen < (socklen_t)sizeof(*in4)) + return -1; + xa->af = AF_INET; + memcpy(&xa->v4, &in4->sin_addr, sizeof(xa->v4)); + break; + case AF_INET6: + if (slen < (socklen_t)sizeof(*in6)) + return -1; + xa->af = AF_INET6; + memcpy(&xa->v6, &in6->sin6_addr, sizeof(xa->v6)); +#ifdef HAVE_STRUCT_SOCKADDR_IN6_SIN6_SCOPE_ID + xa->scope_id = in6->sin6_scope_id; +#endif + break; + default: + return -1; + } + + return 0; +} + +int +addr_invert(struct xaddr *n) +{ + int i; + + if (n == NULL) + return -1; + + switch (n->af) { + case AF_INET: + n->v4.s_addr = ~n->v4.s_addr; + return 0; + case AF_INET6: + for (i = 0; i < 4; i++) + n->addr32[i] = ~n->addr32[i]; + return 0; + default: + return -1; + } +} + +/* + * Calculate a netmask of length 'l' for address family 'af' and + * store it in 'n'. + * Returns 0 on success, -1 on failure. + */ +int +addr_netmask(int af, u_int l, struct xaddr *n) +{ + int i; + + if (masklen_valid(af, l) != 0 || n == NULL) + return -1; + + memset(n, '\0', sizeof(*n)); + switch (af) { + case AF_INET: + n->af = AF_INET; + if (l == 0) + return 0; + n->v4.s_addr = htonl((0xffffffff << (32 - l)) & 0xffffffff); + return 0; + case AF_INET6: + n->af = AF_INET6; + for (i = 0; i < 4 && l >= 32; i++, l -= 32) + n->addr32[i] = 0xffffffffU; + if (i < 4 && l != 0) + n->addr32[i] = htonl((0xffffffff << (32 - l)) & + 0xffffffff); + return 0; + default: + return -1; + } +} + +int +addr_hostmask(int af, u_int l, struct xaddr *n) +{ + if (addr_netmask(af, l, n) == -1 || addr_invert(n) == -1) + return -1; + return 0; +} + +/* + * Perform logical AND of addresses 'a' and 'b', storing result in 'dst'. + * Returns 0 on success, -1 on failure. + */ +int +addr_and(struct xaddr *dst, const struct xaddr *a, const struct xaddr *b) +{ + int i; + + if (dst == NULL || a == NULL || b == NULL || a->af != b->af) + return -1; + + memcpy(dst, a, sizeof(*dst)); + switch (a->af) { + case AF_INET: + dst->v4.s_addr &= b->v4.s_addr; + return 0; + case AF_INET6: + dst->scope_id = a->scope_id; + for (i = 0; i < 4; i++) + dst->addr32[i] &= b->addr32[i]; + return 0; + default: + return -1; + } +} + +int +addr_or(struct xaddr *dst, const struct xaddr *a, const struct xaddr *b) +{ + int i; + + if (dst == NULL || a == NULL || b == NULL || a->af != b->af) + return (-1); + + memcpy(dst, a, sizeof(*dst)); + switch (a->af) { + case AF_INET: + dst->v4.s_addr |= b->v4.s_addr; + return (0); + case AF_INET6: + for (i = 0; i < 4; i++) + dst->addr32[i] |= b->addr32[i]; + return (0); + default: + return (-1); + } +} + +int +addr_cmp(const struct xaddr *a, const struct xaddr *b) +{ + int i; + + if (a->af != b->af) + return (a->af == AF_INET6 ? 1 : -1); + + switch (a->af) { + case AF_INET: + /* + * Can't just subtract here as 255.255.255.255 - 0.0.0.0 is + * too big to fit into a signed int + */ + if (a->v4.s_addr == b->v4.s_addr) + return 0; + return (ntohl(a->v4.s_addr) > ntohl(b->v4.s_addr) ? 1 : -1); + case AF_INET6: + /* + * Do this a byte at a time to avoid the above issue and + * any endian problems + */ + for (i = 0; i < 16; i++) + if (a->addr8[i] - b->addr8[i] != 0) + return (a->addr8[i] - b->addr8[i]); + if (a->scope_id == b->scope_id) + return (0); + return (a->scope_id > b->scope_id ? 1 : -1); + default: + return (-1); + } +} + +int +addr_is_all0s(const struct xaddr *a) +{ + int i; + + switch (a->af) { + case AF_INET: + return (a->v4.s_addr == 0 ? 0 : -1); + case AF_INET6: + for (i = 0; i < 4; i++) + if (a->addr32[i] != 0) + return -1; + return 0; + default: + return -1; + } +} + +/* Increment the specified address. Note, does not do overflow checking */ +void +addr_increment(struct xaddr *a) +{ + int i; + uint32_t n; + + switch (a->af) { + case AF_INET: + a->v4.s_addr = htonl(ntohl(a->v4.s_addr) + 1); + break; + case AF_INET6: + for (i = 0; i < 4; i++) { + /* Increment with carry */ + n = ntohl(a->addr32[3 - i]) + 1; + a->addr32[3 - i] = htonl(n); + if (n != 0) + break; + } + break; + } +} + +/* + * Test whether host portion of address 'a', as determined by 'masklen' + * is all zeros. + * Returns 0 if host portion of address is all-zeros, + * -1 if not all zeros or on failure. + */ +int +addr_host_is_all0s(const struct xaddr *a, u_int masklen) +{ + struct xaddr tmp_addr, tmp_mask, tmp_result; + + memcpy(&tmp_addr, a, sizeof(tmp_addr)); + if (addr_hostmask(a->af, masklen, &tmp_mask) == -1) + return -1; + if (addr_and(&tmp_result, &tmp_addr, &tmp_mask) == -1) + return -1; + return addr_is_all0s(&tmp_result); +} + +#if 0 +int +addr_host_to_all0s(struct xaddr *a, u_int masklen) +{ + struct xaddr tmp_mask; + + if (addr_netmask(a->af, masklen, &tmp_mask) == -1) + return (-1); + if (addr_and(a, a, &tmp_mask) == -1) + return (-1); + return (0); +} +#endif + +int +addr_host_to_all1s(struct xaddr *a, u_int masklen) +{ + struct xaddr tmp_mask; + + if (addr_hostmask(a->af, masklen, &tmp_mask) == -1) + return (-1); + if (addr_or(a, a, &tmp_mask) == -1) + return (-1); + return (0); +} + +/* + * Parse string address 'p' into 'n'. + * Returns 0 on success, -1 on failure. + */ +int +addr_pton(const char *p, struct xaddr *n) +{ + struct addrinfo hints, *ai; + + memset(&hints, '\0', sizeof(hints)); + hints.ai_flags = AI_NUMERICHOST; + + if (p == NULL || getaddrinfo(p, NULL, &hints, &ai) != 0) + return -1; + + if (ai == NULL) + return -1; + + if (ai->ai_addr == NULL) { + freeaddrinfo(ai); + return -1; + } + + if (n != NULL && addr_sa_to_xaddr(ai->ai_addr, ai->ai_addrlen, + n) == -1) { + freeaddrinfo(ai); + return -1; + } + + freeaddrinfo(ai); + return 0; +} + +int +addr_sa_pton(const char *h, const char *s, struct sockaddr *sa, socklen_t slen) +{ + struct addrinfo hints, *ai; + + memset(&hints, '\0', sizeof(hints)); + hints.ai_flags = AI_NUMERICHOST; + + if (h == NULL || getaddrinfo(h, s, &hints, &ai) != 0) + return -1; + + if (ai == NULL) + return -1; + + if (ai->ai_addr == NULL) { + freeaddrinfo(ai); + return -1; + } + + if (sa != NULL) { + if (slen < ai->ai_addrlen) { + freeaddrinfo(ai); + return -1; + } + memcpy(sa, &ai->ai_addr, ai->ai_addrlen); + } + + freeaddrinfo(ai); + return 0; +} + +int +addr_ntop(const struct xaddr *n, char *p, size_t len) +{ + struct sockaddr_storage ss; + socklen_t slen = sizeof(ss); + + if (addr_xaddr_to_sa(n, _SA(&ss), &slen, 0) == -1) + return -1; + if (p == NULL || len == 0) + return -1; + if (getnameinfo(_SA(&ss), slen, p, len, NULL, 0, + NI_NUMERICHOST) != 0) + return -1; + + return 0; +} + +/* + * Parse a CIDR address (x.x.x.x/y or xxxx:yyyy::/z). + * Return -1 on parse error, -2 on inconsistency or 0 on success. + */ +int +addr_pton_cidr(const char *p, struct xaddr *n, u_int *l) +{ + struct xaddr tmp; + long unsigned int masklen = 999; + char addrbuf[64], *mp, *cp; + + /* Don't modify argument */ + if (p == NULL || strlcpy(addrbuf, p, sizeof(addrbuf)) >= sizeof(addrbuf)) + return -1; + + if ((mp = strchr(addrbuf, '/')) != NULL) { + *mp = '\0'; + mp++; + masklen = strtoul(mp, &cp, 10); + if (*mp < '0' || *mp > '9' || *cp != '\0' || masklen > 128) + return -1; + } + + if (addr_pton(addrbuf, &tmp) == -1) + return -1; + + if (mp == NULL) + masklen = addr_unicast_masklen(tmp.af); + if (masklen_valid(tmp.af, masklen) == -1) + return -2; + if (addr_host_is_all0s(&tmp, masklen) != 0) + return -2; + + if (n != NULL) + memcpy(n, &tmp, sizeof(*n)); + if (l != NULL) + *l = masklen; + + return 0; +} + +int +addr_netmatch(const struct xaddr *host, const struct xaddr *net, u_int masklen) +{ + struct xaddr tmp_mask, tmp_result; + + if (host->af != net->af) + return -1; + + if (addr_netmask(host->af, masklen, &tmp_mask) == -1) + return -1; + if (addr_and(&tmp_result, host, &tmp_mask) == -1) + return -1; + return addr_cmp(&tmp_result, net); +} |