+++ /dev/null
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
- This file is part of systemd.
-
- Copyright 2008-2011 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd 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
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-#include <nss.h>
-#include <netdb.h>
-#include <errno.h>
-#include <string.h>
-#include <net/if.h>
-#include <stdlib.h>
-
-#include "local-addresses.h"
-#include "macro.h"
-#include "nss-util.h"
-#include "util.h"
-
-/* We use 127.0.0.2 as IPv4 address. This has the advantage over
- * 127.0.0.1 that it can be translated back to the local hostname. For
- * IPv6 we use ::1 which unfortunately will not translate back to the
- * hostname but instead something like "localhost" or so. */
-
-#define LOCALADDRESS_IPV4 (htonl(0x7F000002))
-#define LOCALADDRESS_IPV6 &in6addr_loopback
-#define LOOPBACK_INTERFACE "lo"
-
-NSS_GETHOSTBYNAME_PROTOTYPES(myhostname);
-NSS_GETHOSTBYADDR_PROTOTYPES(myhostname);
-
-static bool is_gateway(const char *hostname) {
- assert(hostname);
-
- return streq(hostname, "gateway") ||
- streq(hostname, "gateway.");
-}
-
-enum nss_status _nss_myhostname_gethostbyname4_r(
- const char *name,
- struct gaih_addrtuple **pat,
- char *buffer, size_t buflen,
- int *errnop, int *h_errnop,
- int32_t *ttlp) {
-
- struct gaih_addrtuple *r_tuple, *r_tuple_prev = NULL;
- _cleanup_free_ struct local_address *addresses = NULL;
- _cleanup_free_ char *hn = NULL;
- const char *canonical = NULL;
- int n_addresses = 0, lo_ifi;
- uint32_t local_address_ipv4;
- struct local_address *a;
- size_t l, idx, ms;
- char *r_name;
- unsigned n;
-
- assert(name);
- assert(pat);
- assert(buffer);
- assert(errnop);
- assert(h_errnop);
-
- if (is_localhost(name)) {
- /* We respond to 'localhost', so that /etc/hosts
- * is optional */
-
- canonical = "localhost";
- local_address_ipv4 = htonl(INADDR_LOOPBACK);
-
- } else if (is_gateway(name)) {
-
- n_addresses = local_gateways(NULL, 0, AF_UNSPEC, &addresses);
- if (n_addresses <= 0) {
- *errnop = ENOENT;
- *h_errnop = HOST_NOT_FOUND;
- return NSS_STATUS_NOTFOUND;
- }
-
- canonical = "gateway";
-
- } else {
- hn = gethostname_malloc();
- if (!hn) {
- *errnop = ENOMEM;
- *h_errnop = NO_RECOVERY;
- return NSS_STATUS_TRYAGAIN;
- }
-
- /* We respond to our local host name, our our hostname suffixed with a single dot. */
- if (!streq(name, hn) && !streq_ptr(startswith(name, hn), ".")) {
- *errnop = ENOENT;
- *h_errnop = HOST_NOT_FOUND;
- return NSS_STATUS_NOTFOUND;
- }
-
- n_addresses = local_addresses(NULL, 0, AF_UNSPEC, &addresses);
- if (n_addresses < 0)
- n_addresses = 0;
-
- canonical = hn;
- local_address_ipv4 = LOCALADDRESS_IPV4;
- }
-
- /* If this call fails we fill in 0 as scope. Which is fine */
- lo_ifi = n_addresses <= 0 ? if_nametoindex(LOOPBACK_INTERFACE) : 0;
-
- l = strlen(canonical);
- ms = ALIGN(l+1) + ALIGN(sizeof(struct gaih_addrtuple)) * (n_addresses > 0 ? n_addresses : 2);
- if (buflen < ms) {
- *errnop = ENOMEM;
- *h_errnop = NO_RECOVERY;
- return NSS_STATUS_TRYAGAIN;
- }
-
- /* First, fill in hostname */
- r_name = buffer;
- memcpy(r_name, canonical, l+1);
- idx = ALIGN(l+1);
-
- if (n_addresses <= 0) {
- /* Second, fill in IPv6 tuple */
- r_tuple = (struct gaih_addrtuple*) (buffer + idx);
- r_tuple->next = r_tuple_prev;
- r_tuple->name = r_name;
- r_tuple->family = AF_INET6;
- memcpy(r_tuple->addr, LOCALADDRESS_IPV6, 16);
- r_tuple->scopeid = (uint32_t) lo_ifi;
-
- idx += ALIGN(sizeof(struct gaih_addrtuple));
- r_tuple_prev = r_tuple;
-
- /* Third, fill in IPv4 tuple */
- r_tuple = (struct gaih_addrtuple*) (buffer + idx);
- r_tuple->next = r_tuple_prev;
- r_tuple->name = r_name;
- r_tuple->family = AF_INET;
- *(uint32_t*) r_tuple->addr = local_address_ipv4;
- r_tuple->scopeid = (uint32_t) lo_ifi;
-
- idx += ALIGN(sizeof(struct gaih_addrtuple));
- r_tuple_prev = r_tuple;
- }
-
- /* Fourth, fill actual addresses in, but in backwards order */
- for (a = addresses + n_addresses - 1, n = 0; (int) n < n_addresses; n++, a--) {
- r_tuple = (struct gaih_addrtuple*) (buffer + idx);
- r_tuple->next = r_tuple_prev;
- r_tuple->name = r_name;
- r_tuple->family = a->family;
- r_tuple->scopeid = a->ifindex;
- memcpy(r_tuple->addr, &a->address, 16);
-
- idx += ALIGN(sizeof(struct gaih_addrtuple));
- r_tuple_prev = r_tuple;
- }
-
- /* Verify the size matches */
- assert(idx == ms);
-
- /* Nscd expects us to store the first record in **pat. */
- if (*pat)
- **pat = *r_tuple_prev;
- else
- *pat = r_tuple_prev;
-
- if (ttlp)
- *ttlp = 0;
-
- /* Explicitly reset all error variables */
- *errnop = 0;
- *h_errnop = NETDB_SUCCESS;
- h_errno = 0;
-
- return NSS_STATUS_SUCCESS;
-}
-
-static enum nss_status fill_in_hostent(
- const char *canonical, const char *additional,
- int af,
- struct local_address *addresses, unsigned n_addresses,
- uint32_t local_address_ipv4,
- struct hostent *result,
- char *buffer, size_t buflen,
- int *errnop, int *h_errnop,
- int32_t *ttlp,
- char **canonp) {
-
- size_t l_canonical, l_additional, idx, ms, alen;
- char *r_addr, *r_name, *r_aliases, *r_alias = NULL, *r_addr_list;
- struct local_address *a;
- unsigned n, c;
-
- assert(canonical);
- assert(result);
- assert(buffer);
- assert(errnop);
- assert(h_errnop);
-
- alen = FAMILY_ADDRESS_SIZE(af);
-
- for (a = addresses, n = 0, c = 0; n < n_addresses; a++, n++)
- if (af == a->family)
- c++;
-
- l_canonical = strlen(canonical);
- l_additional = additional ? strlen(additional) : 0;
- ms = ALIGN(l_canonical+1)+
- (additional ? ALIGN(l_additional+1) : 0) +
- sizeof(char*) +
- (additional ? sizeof(char*) : 0) +
- (c > 0 ? c : 1) * ALIGN(alen) +
- (c > 0 ? c+1 : 2) * sizeof(char*);
-
- if (buflen < ms) {
- *errnop = ENOMEM;
- *h_errnop = NO_RECOVERY;
- return NSS_STATUS_TRYAGAIN;
- }
-
- /* First, fill in hostnames */
- r_name = buffer;
- memcpy(r_name, canonical, l_canonical+1);
- idx = ALIGN(l_canonical+1);
-
- if (additional) {
- r_alias = buffer + idx;
- memcpy(r_alias, additional, l_additional+1);
- idx += ALIGN(l_additional+1);
- }
-
- /* Second, create aliases array */
- r_aliases = buffer + idx;
- if (additional) {
- ((char**) r_aliases)[0] = r_alias;
- ((char**) r_aliases)[1] = NULL;
- idx += 2*sizeof(char*);
- } else {
- ((char**) r_aliases)[0] = NULL;
- idx += sizeof(char*);
- }
-
- /* Third, add addresses */
- r_addr = buffer + idx;
- if (c > 0) {
- unsigned i = 0;
-
- for (a = addresses, n = 0; n < n_addresses; a++, n++) {
- if (af != a->family)
- continue;
-
- memcpy(r_addr + i*ALIGN(alen), &a->address, alen);
- i++;
- }
-
- assert(i == c);
- idx += c*ALIGN(alen);
- } else {
- if (af == AF_INET)
- *(uint32_t*) r_addr = local_address_ipv4;
- else
- memcpy(r_addr, LOCALADDRESS_IPV6, 16);
-
- idx += ALIGN(alen);
- }
-
- /* Fourth, add address pointer array */
- r_addr_list = buffer + idx;
- if (c > 0) {
- unsigned i;
-
- for (i = 0; i < c; i++)
- ((char**) r_addr_list)[i] = r_addr + i*ALIGN(alen);
-
- ((char**) r_addr_list)[i] = NULL;
- idx += (c+1) * sizeof(char*);
-
- } else {
- ((char**) r_addr_list)[0] = r_addr;
- ((char**) r_addr_list)[1] = NULL;
- idx += 2 * sizeof(char*);
- }
-
- /* Verify the size matches */
- assert(idx == ms);
-
- result->h_name = r_name;
- result->h_aliases = (char**) r_aliases;
- result->h_addrtype = af;
- result->h_length = alen;
- result->h_addr_list = (char**) r_addr_list;
-
- if (ttlp)
- *ttlp = 0;
-
- if (canonp)
- *canonp = r_name;
-
- /* Explicitly reset all error variables */
- *errnop = 0;
- *h_errnop = NETDB_SUCCESS;
- h_errno = 0;
-
- return NSS_STATUS_SUCCESS;
-}
-
-enum nss_status _nss_myhostname_gethostbyname3_r(
- const char *name,
- int af,
- struct hostent *host,
- char *buffer, size_t buflen,
- int *errnop, int *h_errnop,
- int32_t *ttlp,
- char **canonp) {
-
- _cleanup_free_ struct local_address *addresses = NULL;
- const char *canonical, *additional = NULL;
- _cleanup_free_ char *hn = NULL;
- uint32_t local_address_ipv4 = 0;
- int n_addresses = 0;
-
- assert(name);
- assert(host);
- assert(buffer);
- assert(errnop);
- assert(h_errnop);
-
- if (af == AF_UNSPEC)
- af = AF_INET;
-
- if (af != AF_INET && af != AF_INET6) {
- *errnop = EAFNOSUPPORT;
- *h_errnop = NO_DATA;
- return NSS_STATUS_UNAVAIL;
- }
-
- if (is_localhost(name)) {
- canonical = "localhost";
- local_address_ipv4 = htonl(INADDR_LOOPBACK);
-
- } else if (is_gateway(name)) {
-
- n_addresses = local_gateways(NULL, 0, af, &addresses);
- if (n_addresses <= 0) {
- *errnop = ENOENT;
- *h_errnop = HOST_NOT_FOUND;
- return NSS_STATUS_NOTFOUND;
- }
-
- canonical = "gateway";
-
- } else {
- hn = gethostname_malloc();
- if (!hn) {
- *errnop = ENOMEM;
- *h_errnop = NO_RECOVERY;
- return NSS_STATUS_TRYAGAIN;
- }
-
- if (!streq(name, hn) && !streq_ptr(startswith(name, hn), ".")) {
- *errnop = ENOENT;
- *h_errnop = HOST_NOT_FOUND;
- return NSS_STATUS_NOTFOUND;
- }
-
- n_addresses = local_addresses(NULL, 0, af, &addresses);
- if (n_addresses < 0)
- n_addresses = 0;
-
- canonical = hn;
- additional = n_addresses <= 0 && af == AF_INET6 ? "localhost" : NULL;
- local_address_ipv4 = LOCALADDRESS_IPV4;
- }
-
- return fill_in_hostent(
- canonical, additional,
- af,
- addresses, n_addresses,
- local_address_ipv4,
- host,
- buffer, buflen,
- errnop, h_errnop,
- ttlp,
- canonp);
-}
-
-enum nss_status _nss_myhostname_gethostbyaddr2_r(
- const void* addr, socklen_t len,
- int af,
- struct hostent *host,
- char *buffer, size_t buflen,
- int *errnop, int *h_errnop,
- int32_t *ttlp) {
-
- const char *canonical = NULL, *additional = NULL;
- uint32_t local_address_ipv4 = LOCALADDRESS_IPV4;
- _cleanup_free_ struct local_address *addresses = NULL;
- _cleanup_free_ char *hn = NULL;
- int n_addresses = 0;
- struct local_address *a;
- bool additional_from_hostname = false;
- unsigned n;
-
- assert(addr);
- assert(host);
- assert(buffer);
- assert(errnop);
- assert(h_errnop);
-
- if (!IN_SET(af, AF_INET, AF_INET6)) {
- *errnop = EAFNOSUPPORT;
- *h_errnop = NO_DATA;
- return NSS_STATUS_UNAVAIL;
- }
-
- if (len != FAMILY_ADDRESS_SIZE(af)) {
- *errnop = EINVAL;
- *h_errnop = NO_RECOVERY;
- return NSS_STATUS_UNAVAIL;
- }
-
- if (af == AF_INET) {
- if ((*(uint32_t*) addr) == LOCALADDRESS_IPV4)
- goto found;
-
- if ((*(uint32_t*) addr) == htonl(INADDR_LOOPBACK)) {
- canonical = "localhost";
- local_address_ipv4 = htonl(INADDR_LOOPBACK);
- goto found;
- }
-
- } else {
- assert(af == AF_INET6);
-
- if (memcmp(addr, LOCALADDRESS_IPV6, 16) == 0) {
- canonical = "localhost";
- additional_from_hostname = true;
- goto found;
- }
- }
-
- n_addresses = local_addresses(NULL, 0, AF_UNSPEC, &addresses);
- if (n_addresses > 0) {
- for (a = addresses, n = 0; (int) n < n_addresses; n++, a++) {
- if (af != a->family)
- continue;
-
- if (memcmp(addr, &a->address, FAMILY_ADDRESS_SIZE(af)) == 0)
- goto found;
- }
- }
-
- free(addresses);
- addresses = NULL;
-
- n_addresses = local_gateways(NULL, 0, AF_UNSPEC, &addresses);
- if (n_addresses > 0) {
- for (a = addresses, n = 0; (int) n < n_addresses; n++, a++) {
- if (af != a->family)
- continue;
-
- if (memcmp(addr, &a->address, FAMILY_ADDRESS_SIZE(af)) == 0) {
- canonical = "gateway";
- goto found;
- }
- }
- }
-
- *errnop = ENOENT;
- *h_errnop = HOST_NOT_FOUND;
-
- return NSS_STATUS_NOTFOUND;
-
-found:
- if (!canonical || (!additional && additional_from_hostname)) {
- hn = gethostname_malloc();
- if (!hn) {
- *errnop = ENOMEM;
- *h_errnop = NO_RECOVERY;
- return NSS_STATUS_TRYAGAIN;
- }
-
- if (!canonical)
- canonical = hn;
-
- if (!additional && additional_from_hostname)
- additional = hn;
- }
-
- return fill_in_hostent(
- canonical, additional,
- af,
- addresses, n_addresses,
- local_address_ipv4,
- host,
- buffer, buflen,
- errnop, h_errnop,
- ttlp,
- NULL);
-}
-
-NSS_GETHOSTBYNAME_FALLBACKS(myhostname);
-NSS_GETHOSTBYADDR_FALLBACKS(myhostname);
~ianmdlvl / elogind.git / commitdiff