diff options
Diffstat (limited to 'src/contrib/sockaddr.c')
| -rw-r--r-- | src/contrib/sockaddr.c | 368 |
1 files changed, 368 insertions, 0 deletions
diff --git a/src/contrib/sockaddr.c b/src/contrib/sockaddr.c new file mode 100644 index 0000000..2b3218b --- /dev/null +++ b/src/contrib/sockaddr.c @@ -0,0 +1,368 @@ +/* Copyright (C) 2023 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz> + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. + */ + +#include <assert.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <netdb.h> + +#include "libknot/errcode.h" +#include "contrib/sockaddr.h" +#include "contrib/openbsd/strlcpy.h" +#include "contrib/macros.h" +#include "contrib/musl/inet_ntop.h" + +int sockaddr_len(const struct sockaddr_storage *ss) +{ + if (ss == NULL) { + return 0; + } + + switch(ss->ss_family) { + case AF_INET: + return sizeof(struct sockaddr_in); + case AF_INET6: + return sizeof(struct sockaddr_in6); + case AF_UNIX: + return sizeof(struct sockaddr_un); + default: + return 0; + } +} + +static int cmp_ipv4(const struct sockaddr_in *a, const struct sockaddr_in *b, + bool ignore_port) +{ + if (a->sin_addr.s_addr < b->sin_addr.s_addr) { + return -1; + } else if (a->sin_addr.s_addr > b->sin_addr.s_addr) { + return 1; + } else { + return ignore_port ? 0 : a->sin_port - b->sin_port; + } +} + +static int cmp_ipv6(const struct sockaddr_in6 *a, const struct sockaddr_in6 *b, + bool ignore_port) +{ + int ret = memcmp(&a->sin6_addr, &b->sin6_addr, sizeof(struct in6_addr)); + if (ret == 0) { + ret = ignore_port ? 0 : a->sin6_port - b->sin6_port; + } + + return ret; +} + +static int cmp_unix(const struct sockaddr_un *a, const struct sockaddr_un *b) +{ + int len_a = strnlen(a->sun_path, sizeof(a->sun_path)); + int len_b = strnlen(b->sun_path, sizeof(b->sun_path)); + int len_min = len_a <= len_b ? len_a : len_b; + + int ret = strncmp(a->sun_path, b->sun_path, len_min); + if (ret == 0) { + ret = len_a - len_b; + } + + return ret; +} + +int sockaddr_cmp(const struct sockaddr_storage *a, const struct sockaddr_storage *b, + bool ignore_port) +{ + assert(a); + assert(b); + if (a->ss_family != b->ss_family) { + return (int)a->ss_family - (int)b->ss_family; + } + + switch (a->ss_family) { + case AF_UNSPEC: + return 0; + case AF_INET: + return cmp_ipv4((struct sockaddr_in *)a, (struct sockaddr_in *)b, + ignore_port); + case AF_INET6: + return cmp_ipv6((struct sockaddr_in6 *)a, (struct sockaddr_in6 *)b, + ignore_port); + case AF_UNIX: + return cmp_unix((struct sockaddr_un *)a, (struct sockaddr_un *)b); + default: + return 1; + } +} + +int sockaddr_set(struct sockaddr_storage *ss, int family, const char *straddr, int port) +{ + if (ss == NULL || straddr == NULL) { + return KNOT_EINVAL; + } + + /* Set family and port. */ + memset(ss, 0, sizeof(*ss)); + ss->ss_family = family; + sockaddr_port_set(ss, port); + + /* Initialize address depending on address family. */ + if (family == AF_INET6) { + struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)ss; + if (inet_pton(family, straddr, &ipv6->sin6_addr) < 1) { + return KNOT_ERROR; + } + return KNOT_EOK; + } else if (family == AF_INET) { + struct sockaddr_in *ipv4 = (struct sockaddr_in *)ss; + if (inet_pton(family, straddr, &ipv4->sin_addr) < 1) { + return KNOT_ERROR; + } + return KNOT_EOK; + } else if (family == AF_UNIX) { + struct sockaddr_un *un = (struct sockaddr_un *)ss; + size_t ret = strlcpy(un->sun_path, straddr, sizeof(un->sun_path)); + if (ret >= sizeof(un->sun_path)) { + return KNOT_ESPACE; + } + return KNOT_EOK; + } + + return KNOT_EINVAL; +} + +void *sockaddr_raw(const struct sockaddr_storage *ss, size_t *addr_size) +{ + if (ss == NULL || addr_size == NULL) { + return NULL; + } + + if (ss->ss_family == AF_INET) { + struct sockaddr_in *ipv4 = (struct sockaddr_in *)ss; + *addr_size = sizeof(ipv4->sin_addr); + return &ipv4->sin_addr; + } else if (ss->ss_family == AF_INET6) { + struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)ss; + *addr_size = sizeof(ipv6->sin6_addr); + return &ipv6->sin6_addr; + } else if (ss->ss_family == AF_UNIX) { + struct sockaddr_un *un = (struct sockaddr_un *)ss; + *addr_size = sizeof(un->sun_path); + return un->sun_path; + } else { + return NULL; + } +} + +int sockaddr_set_raw(struct sockaddr_storage *ss, int family, + const uint8_t *raw_addr, size_t raw_addr_size) +{ + if (ss == NULL || raw_addr == NULL) { + return KNOT_EINVAL; + } + + memset(ss, 0, sizeof(*ss)); + ss->ss_family = family; + + size_t ss_size = 0; + void *ss_data = sockaddr_raw(ss, &ss_size); + if (ss_data == NULL || + (family != AF_UNIX && ss_size != raw_addr_size) || + (family == AF_UNIX && ss_size <= raw_addr_size)) { + return KNOT_EINVAL; + } + + memcpy(ss_data, raw_addr, raw_addr_size); + + return KNOT_EOK; +} + +int sockaddr_tostr(char *buf, size_t maxlen, const struct sockaddr_storage *ss) +{ + if (ss == NULL || buf == NULL) { + return KNOT_EINVAL; + } + + const char *out = NULL; + + /* Convert network address string. */ + if (ss->ss_family == AF_INET6) { + const struct sockaddr_in6 *s = (const struct sockaddr_in6 *)ss; + out = knot_inet_ntop(ss->ss_family, &s->sin6_addr, buf, maxlen); + } else if (ss->ss_family == AF_INET) { + const struct sockaddr_in *s = (const struct sockaddr_in *)ss; + out = knot_inet_ntop(ss->ss_family, &s->sin_addr, buf, maxlen); + } else if (ss->ss_family == AF_UNIX) { + const struct sockaddr_un *s = (const struct sockaddr_un *)ss; + const char *path = (s->sun_path[0] != '\0' ? s->sun_path : "UNIX socket"); + size_t ret = strlcpy(buf, path, maxlen); + out = (ret < maxlen) ? buf : NULL; + } else { + *buf = '\0'; + return KNOT_EINVAL; + } + + if (out == NULL) { + *buf = '\0'; + return KNOT_ESPACE; + } + + /* Write separator and port. */ + int written = strlen(buf); + int port = sockaddr_port(ss); + if (port > 0) { + int ret = snprintf(&buf[written], maxlen - written, "@%d", port); + if (ret <= 0 || (size_t)ret >= maxlen - written) { + *buf = '\0'; + return KNOT_ESPACE; + } + + written += ret; + } + + return written; +} + +int sockaddr_port(const struct sockaddr_storage *ss) +{ + if (ss == NULL) { + return KNOT_EINVAL; + } + + if (ss->ss_family == AF_INET6) { + return ntohs(((struct sockaddr_in6 *)ss)->sin6_port); + } else if (ss->ss_family == AF_INET) { + return ntohs(((struct sockaddr_in *)ss)->sin_port); + } else { + return KNOT_EINVAL; + } +} + +void sockaddr_port_set(struct sockaddr_storage *ss, uint16_t port) +{ + if (ss == NULL) { + return; + } + + if (ss->ss_family == AF_INET6) { + ((struct sockaddr_in6 *)ss)->sin6_port = htons(port); + } else if (ss->ss_family == AF_INET) { + ((struct sockaddr_in *)ss)->sin_port = htons(port); + } +} + +char *sockaddr_hostname(void) +{ + /* Fetch hostname. */ + char host[256] = ""; + if (gethostname(host, sizeof(host)) != 0) { + return NULL; + } + /* Just to be sure. */ + host[sizeof(host) - 1] = '\0'; + + /* Fetch canonical name for this address/DNS. */ + struct addrinfo hints, *info = NULL; + memset(&hints, 0, sizeof hints); + hints.ai_family = AF_UNSPEC; + hints.ai_socktype = SOCK_DGRAM; + hints.ai_flags = AI_CANONNAME; + if (getaddrinfo(host, "domain", &hints, &info) != 0) { + return NULL; + } + + /* Fetch first valid hostname. */ + char *hname = NULL; + struct addrinfo *p = NULL; + for (p = info; p != NULL; p = p->ai_next) { + if (p->ai_canonname) { + hname = strdup(p->ai_canonname); + break; + } + } + + /* No valid hostname found, resort to gethostname() result */ + if (hname == NULL) { + hname = strdup(host); + } + + freeaddrinfo(info); + return hname; +} + +bool sockaddr_is_any(const struct sockaddr_storage *ss) +{ + if (ss == NULL) { + return false; + } + + if (ss->ss_family == AF_INET) { + const struct sockaddr_in *ipv4 = (struct sockaddr_in *)ss; + return ipv4->sin_addr.s_addr == INADDR_ANY; + } + + if (ss->ss_family == AF_INET6) { + const struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)ss; + return memcmp(&ipv6->sin6_addr, &in6addr_any, sizeof(ipv6->sin6_addr)) == 0; + } + + return false; +} + +bool sockaddr_net_match(const struct sockaddr_storage *ss1, + const struct sockaddr_storage *ss2, + unsigned prefix) +{ + if (ss1 == NULL || ss2 == NULL) { + return false; + } + + if (ss1->ss_family != ss2->ss_family) { + return false; + } + + size_t raw_len = 0; + const uint8_t *raw_1 = sockaddr_raw(ss1, &raw_len); + const uint8_t *raw_2 = sockaddr_raw(ss2, &raw_len); + + prefix = MIN(prefix, raw_len * 8); + unsigned bytes = prefix / 8; + unsigned bits = prefix % 8; + + /* Compare full bytes. */ + if (memcmp(raw_1, raw_2, bytes) != 0) { + return false; + } + + /* Compare last partial byte. */ + return bits == 0 || + (raw_1[bytes] >> (8 - bits) == raw_2[bytes] >> (8 - bits)); +} + +bool sockaddr_range_match(const struct sockaddr_storage *ss, + const struct sockaddr_storage *ss_min, + const struct sockaddr_storage *ss_max) +{ + if (ss == NULL || ss_min == NULL || ss_max == NULL) { + return false; + } + + if (ss_min->ss_family != ss_max->ss_family || + ss_min->ss_family != ss->ss_family) { + return false; + } + + return sockaddr_cmp(ss, ss_min, true) >= 0 && + sockaddr_cmp(ss, ss_max, true) <= 0; +} |