-/* $Id$ */
-
-/*
- * This file is part of nss-myhostname.
- *
- * nss-myhostname 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.
- *
- * nss-myhostname 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 nss-myhostname; if not, write to the Free
- * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
- * 02110-1301 USA
- */
+/*-*- Mode: C; c-basic-offset: 8 -*-*/
+
+
+/***
+ This file is part of nss-myhostname.
+
+ Copyright 2008 Lennart Poettering
+
+ nss-myhostname 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.
+
+ nss-myhostname 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 nss-myhostname. If not, If not, see
+ <http://www.gnu.org/licenses/>.
+***/
#include <limits.h>
#include <nss.h>
#include <stdio.h>
#include <assert.h>
#include <unistd.h>
+#include <net/if.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 "localhost6" or so. */
+
+#define LOCALADDRESS_IPV4 (htonl(0x7F000002))
+#define LOCALADDRESS_IPV6 &in6addr_loopback
+#define LOOPBACK_INTERFACE "lo"
+
+#define ALIGN(a) (((a+sizeof(void*)-1)/sizeof(void*))*sizeof(void*))
+
+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) {
+
+ unsigned ifi;
+ char hn[HOST_NAME_MAX+1];
+ size_t l, idx, ms;
+ char *r_name;
+ struct gaih_addrtuple *r_tuple1, *r_tuple2;
+
+ memset(hn, 0, sizeof(hn));
+ if (gethostname(hn, sizeof(hn)-1) < 0) {
+ *errnop = errno;
+ *h_errnop = NO_RECOVERY;
+ return NSS_STATUS_UNAVAIL;
+ }
+
+ if (strcasecmp(name, hn) != 0) {
+ *errnop = ENOENT;
+ *h_errnop = HOST_NOT_FOUND;
+ return NSS_STATUS_NOTFOUND;
+ }
-#define LOCALADDRESS (htonl(0x7F000002))
+ /* If this call fails we fill in 0 as scope. Which is fine */
+ ifi = if_nametoindex(LOOPBACK_INTERFACE);
+
+ l = strlen(hn);
+ ms = ALIGN(l+1)+ALIGN(sizeof(struct gaih_addrtuple))*2;
+ if (buflen < ms) {
+ *errnop = ENOMEM;
+ *h_errnop = NO_RECOVERY;
+ return NSS_STATUS_TRYAGAIN;
+ }
+
+ /* First, fill in hostname */
+ r_name = buffer;
+ memcpy(r_name, hn, l+1);
+ idx = ALIGN(l+1);
+
+ /* Second, fill in IPv4 tuple */
+ r_tuple1 = (struct gaih_addrtuple*) (buffer + idx);
+ r_tuple1->next = NULL;
+ r_tuple1->name = r_name;
+ r_tuple1->family = AF_INET;
+ *(uint32_t*) r_tuple1->addr = LOCALADDRESS_IPV4;
+ r_tuple1->scopeid = (uint32_t) ifi;
+ idx += ALIGN(sizeof(struct gaih_addrtuple));
+
+ /* Third, fill in IPv6 tuple */
+ r_tuple2 = (struct gaih_addrtuple*) (buffer + idx);
+ r_tuple2->next = r_tuple1;
+ r_tuple2->name = r_name;
+ r_tuple2->family = AF_INET6;
+ memcpy(r_tuple2->addr, LOCALADDRESS_IPV6, 16);
+ r_tuple1->scopeid = (uint32_t) ifi;
+ idx += ALIGN(sizeof(struct gaih_addrtuple));
+
+ /* Verify the size matches */
+ assert(idx == ms);
+
+ *pat = r_tuple2;
+
+ if (ttlp)
+ *ttlp = 0;
+
+ return NSS_STATUS_SUCCESS;
+}
static enum nss_status fill_in_hostent(
- const char *hn,
- struct hostent *result,
- char *buffer,
- size_t buflen,
- int *errnop,
- int *h_errnop) {
-
- size_t l, idx;
- char *r_addr, *r_name, *r_aliases, *r_addr_list;
-
- l = strlen(hn);
- if (buflen < l+1+sizeof(char*)+4+sizeof(char*)*2) {
- *errnop = ENOMEM;
- *h_errnop = NO_RECOVERY;
- return NSS_STATUS_TRYAGAIN;
- }
-
- r_name = buffer;
- strcpy(buffer, hn);
-
- idx = l+1;
-
- *(char**) (buffer + idx) = NULL;
- r_aliases = buffer + idx;
- idx += sizeof(char*);
-
- r_addr = buffer + idx;
- *(uint32_t*) &buffer[idx] = LOCALADDRESS;
- idx += 4;
-
- r_addr_list = buffer + idx;
- * (char**) (buffer + idx) = r_addr;
- * (((char**) (buffer + idx)) +1) = NULL;
-
- result->h_name = r_name;
- result->h_aliases = (char**) r_aliases;
- result->h_addrtype = AF_INET;
- result->h_length = 4;
- result->h_addr_list = (char**) r_addr_list;
-
- return NSS_STATUS_SUCCESS;
+ const char *hn,
+ int af,
+ struct hostent *result,
+ char *buffer, size_t buflen,
+ int *errnop, int *h_errnop,
+ int32_t *ttlp,
+ char **canonp) {
+
+ size_t l, idx, ms;
+ char *r_addr, *r_name, *r_aliases, *r_addr_list;
+ size_t alen;
+
+ alen = af == AF_INET ? 4 : 16;
+
+ l = strlen(hn);
+ ms = ALIGN(l+1)+sizeof(char*)+ALIGN(alen)+sizeof(char*)*2;
+ if (buflen < ms) {
+ *errnop = ENOMEM;
+ *h_errnop = NO_RECOVERY;
+ return NSS_STATUS_TRYAGAIN;
+ }
+
+ /* First, fill in hostname */
+ r_name = buffer;
+ memcpy(r_name, hn, l+1);
+ idx = ALIGN(l+1);
+
+ /* Second, create aliases array */
+ r_aliases = buffer + idx;
+ *(char**) r_aliases = NULL;
+ idx += sizeof(char*);
+
+ /* Third, add address */
+ r_addr = buffer + idx;
+ if (af == AF_INET)
+ *(uint32_t*) r_addr = LOCALADDRESS_IPV4;
+ else
+ memcpy(r_addr, LOCALADDRESS_IPV6, 16);
+ idx += ALIGN(alen);
+
+ /* Fourth, add address pointer array */
+ r_addr_list = buffer + idx;
+ ((char**) r_addr_list)[0] = r_addr;
+ ((char**) r_addr_list)[1] = NULL;
+ idx += sizeof(char*)*2;
+
+ /* 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;
+
+ return NSS_STATUS_SUCCESS;
}
-enum nss_status _nss_myhostname_gethostbyname2_r(
- const char *name,
- int af,
- struct hostent * result,
- char *buffer,
- size_t buflen,
- int *errnop,
- int *h_errnop) {
+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) {
- char hn[HOST_NAME_MAX+1];
+ char hn[HOST_NAME_MAX+1];
- assert(errnop);
- assert(h_errnop);
+ if (af == AF_UNSPEC)
+ af = AF_INET;
- 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 (af != AF_INET) {
- *errnop = ENOENT;
- *h_errnop = HOST_NOT_FOUND;
- return NSS_STATUS_NOTFOUND;
- }
+ memset(hn, 0, sizeof(hn));
+ if (gethostname(hn, sizeof(hn)-1) < 0) {
+ *errnop = errno;
+ *h_errnop = NO_RECOVERY;
+ return NSS_STATUS_UNAVAIL;
+ }
- if (gethostname(hn, sizeof(hn)-1) < 0) {
- *errnop = errno;
- *h_errnop = NO_RECOVERY;
- return NSS_STATUS_TRYAGAIN;
- }
+ if (strcasecmp(name, hn) != 0) {
+ *errnop = ENOENT;
+ *h_errnop = HOST_NOT_FOUND;
+ return NSS_STATUS_NOTFOUND;
+ }
- hn[sizeof(hn)-1] = 0;
+ return fill_in_hostent(hn, af, host, buffer, buflen, errnop, h_errnop, ttlp, canonp);
+}
- if (strcasecmp(name, hn) != 0) {
- *errnop = ENOENT;
- *h_errnop = HOST_NOT_FOUND;
- return NSS_STATUS_NOTFOUND;
- }
+enum nss_status _nss_myhostname_gethostbyname2_r(
+ const char *name,
+ int af,
+ struct hostent *host,
+ char *buffer, size_t buflen,
+ int *errnop, int *h_errnop) {
- return fill_in_hostent(hn, result, buffer, buflen, errnop, h_errnop);
+ return _nss_myhostname_gethostbyname3_r(
+ name,
+ af,
+ host,
+ buffer, buflen,
+ errnop, h_errnop,
+ NULL,
+ NULL);
}
enum nss_status _nss_myhostname_gethostbyname_r (
- const char *name,
- struct hostent *result,
- char *buffer,
- size_t buflen,
- int *errnop,
- int *h_errnop) {
-
- return _nss_myhostname_gethostbyname2_r(
- name,
- AF_UNSPEC,
- result,
- buffer,
- buflen,
- errnop,
- h_errnop);
+ const char *name,
+ struct hostent *host,
+ char *buffer, size_t buflen,
+ int *errnop, int *h_errnop) {
+
+ return _nss_myhostname_gethostbyname3_r(
+ name,
+ AF_UNSPEC,
+ host,
+ buffer, buflen,
+ errnop, h_errnop,
+ NULL,
+ NULL);
}
-enum nss_status _nss_myhostname_gethostbyaddr_r(
- const void* addr,
- int len,
- int af,
- struct hostent *result,
- char *buffer,
- size_t buflen,
- int *errnop,
- int *h_errnop) {
+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) {
- char hn[HOST_NAME_MAX+1];
+ char hn[HOST_NAME_MAX+1];
- assert(errnop);
- assert(h_errnop);
+ if (af == AF_INET) {
+ if (len != 4 ||
+ (*(uint32_t*) addr) != LOCALADDRESS_IPV4)
+ goto not_found;
- if (af != AF_INET || len < 4 || (*(uint32_t*) addr) != LOCALADDRESS) {
+ } else if (af == AF_INET6) {
+ if (len != 16 ||
+ memcmp(addr, LOCALADDRESS_IPV6, 16) != 0)
+ goto not_found;
+ } else {
+ *errnop = EAFNOSUPPORT;
+ *h_errnop = NO_DATA;
+ return NSS_STATUS_UNAVAIL;
+ }
+
+ memset(hn, 0, sizeof(hn));
+ if (gethostname(hn, sizeof(hn)-1) < 0) {
+ *errnop = errno;
+ *h_errnop = NO_RECOVERY;
+ return NSS_STATUS_UNAVAIL;
+ }
+
+ return fill_in_hostent(hn, af, host, buffer, buflen, errnop, h_errnop, ttlp, NULL);
+
+not_found:
*errnop = ENOENT;
*h_errnop = HOST_NOT_FOUND;
return NSS_STATUS_NOTFOUND;
- }
-
- if (gethostname(hn, sizeof(hn)-1) < 0) {
- *errnop = errno;
- *h_errnop = NO_RECOVERY;
- return NSS_STATUS_TRYAGAIN;
- }
+}
- hn[sizeof(hn)-1] = 0;
+enum nss_status _nss_myhostname_gethostbyaddr_r(
+ const void* addr, socklen_t len,
+ int af,
+ struct hostent *host,
+ char *buffer, size_t buflen,
+ int *errnop, int *h_errnop) {
- return fill_in_hostent(hn, result, buffer, buflen, errnop, h_errnop);
+ return _nss_myhostname_gethostbyaddr2_r(
+ addr, len,
+ af,
+ host,
+ buffer, buflen,
+ errnop, h_errnop,
+ NULL);
}
projects / thirdparty / systemd.git / commitdiff
