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Diffstat (limited to 'nss/nss_dns/dns-host.c')
-rw-r--r--nss/nss_dns/dns-host.c611
1 files changed, 611 insertions, 0 deletions
diff --git a/nss/nss_dns/dns-host.c b/nss/nss_dns/dns-host.c
new file mode 100644
index 0000000000..eaa9e81218
--- /dev/null
+++ b/nss/nss_dns/dns-host.c
@@ -0,0 +1,611 @@
+/* Copyright (C) 1996 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+Extended from original form by Ulrich Drepper <drepper@cygnus.com>, 1996.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB. If
+not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA. */
+
+/* Parts of this file are plain copies of the file `getnetnamadr.c' from
+ the bind package and it has the following copyright. */
+
+/* Copyright (c) 1993 Carlos Leandro and Rui Salgueiro
+ * Dep. Matematica Universidade de Coimbra, Portugal, Europe
+ *
+ * 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.
+ */
+/*
+ * Copyright (c) 1983, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <ctype.h>
+#include <errno.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <string.h>
+#include <sys/syslog.h>
+
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <arpa/nameser.h>
+#include <resolv.h>
+
+#include "nsswitch.h"
+
+/* Get implementation for some internal functions. */
+#include "../resolv/mapv4v6addr.h"
+#include "../resolv/mapv4v6hostent.h"
+
+/* Maximum number of aliases we allow. */
+#define MAX_NR_ALIASES 48
+#define MAX_NR_ADDRS 48
+
+#if PACKETSZ > 1024
+# define MAXPACKET PACKETSZ
+#else
+# define MAXPACKET 1024
+#endif
+
+static const char AskedForGot[] = "\
+gethostby*.getanswer: asked for \"%s\", got \"%s\"";
+
+
+/* We need this time later. */
+typedef union querybuf
+{
+ HEADER hdr;
+ u_char buf[MAXPACKET];
+} querybuf;
+
+
+static enum nss_status getanswer_r (const querybuf *answer, int anslen,
+ const char *qname, int qtype,
+ struct hostent *result,
+ char *buffer, int buflen, int *h_errnop);
+
+enum nss_status
+_nss_dns_gethostbyname2_r (const char *name, int af, struct hostent *result,
+ char *buffer, int buflen, int *h_errnop)
+{
+ struct host_data
+ {
+ char *aliases[MAX_NR_ALIASES];
+ unsigned char host_addr[16]; /* IPv4 or IPv6 */
+ char *h_addr_ptrs[MAX_NR_ADDRS + 1];
+ char linebuffer[0];
+ } *host_data = (struct host_data *) buffer;
+ int linebuflen = buflen - offsetof (struct host_data, linebuffer);
+ querybuf host_buffer;
+ int size, type, n;
+ const char *cp;
+
+ switch (af) {
+ case AF_INET:
+ size = INADDRSZ;
+ type = T_A;
+ break;
+ case AF_INET6:
+ size = IN6ADDRSZ;
+ type = T_AAAA;
+ break;
+ default:
+ *h_errnop = NETDB_INTERNAL;
+ errno = EAFNOSUPPORT;
+ return NSS_STATUS_UNAVAIL;
+ }
+
+ result->h_addrtype = af;
+ result->h_length = size;
+
+ /*
+ * if there aren't any dots, it could be a user-level alias.
+ * this is also done in res_query() since we are not the only
+ * function that looks up host names.
+ */
+ if (strchr (name, '.') == NULL && (cp = __hostalias (name)) != NULL)
+ name = cp;
+
+ /*
+ * disallow names consisting only of digits/dots, unless
+ * they end in a dot.
+ */
+ if (isdigit (name[0]))
+ for (cp = name;; ++cp)
+ {
+ if (*cp == '\0')
+ {
+ char *bp;
+
+ if (*--cp == '.')
+ break;
+ /*
+ * All-numeric, no dot at the end. Fake up a hostent
+ * as if we'd actually done a lookup.
+ */
+ if (inet_pton (af, name, host_data->host_addr) <= 0)
+ {
+ *h_errnop = HOST_NOT_FOUND;
+ return NSS_STATUS_NOTFOUND;
+ }
+
+ bp = __stpncpy (host_data->linebuffer, name, linebuflen);
+ host_data->linebuffer[linebuflen - 1] = '\0';
+ linebuflen -= bp - host_data->linebuffer;
+
+ result->h_name = host_data->linebuffer;
+ result->h_aliases = host_data->aliases;
+ host_data->aliases[0] = NULL;
+ host_data->h_addr_ptrs[0] = (char *) host_data->host_addr;
+ host_data->h_addr_ptrs[1] = NULL;
+ result->h_addr_list = host_data->h_addr_ptrs;
+
+ if (_res.options & RES_USE_INET6)
+ map_v4v6_hostent (result, &bp, &linebuflen);
+ *h_errnop = NETDB_SUCCESS;
+ return NSS_STATUS_SUCCESS;
+ }
+ if (!isdigit (*cp) && *cp != '.')
+ break;
+ }
+
+ n = res_search (name, C_IN, type, host_buffer.buf, sizeof (host_buffer));
+ if (n < 0)
+ return errno == ECONNREFUSED ? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND;
+
+ return getanswer_r (&host_buffer, n, name, type, result, buffer, buflen,
+ h_errnop);
+}
+
+
+enum nss_status
+_nss_dns_gethostbyname_r (const char *name, struct hostent *result,
+ char *buffer, int buflen, int *h_errnop)
+{
+ enum nss_status status = NSS_STATUS_NOTFOUND;
+
+ if (_res.options & RES_USE_INET6)
+ status = _nss_dns_gethostbyname2_r (name, AF_INET6, result, buffer,
+ buflen, h_errnop);
+ if (status == NSS_STATUS_NOTFOUND)
+ status = _nss_dns_gethostbyname2_r (name, AF_INET, result, buffer,
+ buflen, h_errnop);
+
+ return status;
+}
+
+
+enum nss_status
+_nss_dns_gethostbyaddr_r (const char *addr, int len, int af,
+ struct hostent *result, char *buffer, int buflen,
+ int *h_errnop)
+{
+ static const u_char mapped[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0xff,0xff };
+ static const u_char tunnelled[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0,0 };
+ const u_char *uaddr = (const u_char *)addr;
+ struct host_data
+ {
+ char *aliases[MAX_NR_ALIASES];
+ unsigned char host_addr[16]; /* IPv4 or IPv6 */
+ char *h_addr_ptrs[MAX_NR_ADDRS + 1];
+ char linebuffer[0];
+ } *host_data = (struct host_data *) buffer;
+ querybuf host_buffer;
+ char qbuf[MAXDNAME+1], *qp;
+ int size, n, status;
+
+ if (af == AF_INET6 && len == IN6ADDRSZ &&
+ (bcmp (uaddr, mapped, sizeof mapped) == 0
+ || bcmp (uaddr, tunnelled, sizeof tunnelled) == 0))
+ {
+ /* Unmap. */
+ addr += sizeof mapped;
+ uaddr += sizeof mapped;
+ af = AF_INET;
+ len = INADDRSZ;
+ }
+
+ switch (af)
+ {
+ case AF_INET:
+ size = INADDRSZ;
+ break;
+ case AF_INET6:
+ size = IN6ADDRSZ;
+ break;
+ default:
+ errno = EAFNOSUPPORT;
+ *h_errnop = NETDB_INTERNAL;
+ return NSS_STATUS_UNAVAIL;
+ }
+ if (size != len)
+ {
+ errno = EAFNOSUPPORT;
+ *h_errnop = NETDB_INTERNAL;
+ return NSS_STATUS_UNAVAIL;
+ }
+
+ switch (af)
+ {
+ case AF_INET:
+ sprintf (qbuf, "%u.%u.%u.%u.in-addr.arpa", (uaddr[3] & 0xff),
+ (uaddr[2] & 0xff), (uaddr[1] & 0xff), (uaddr[0] & 0xff));
+ break;
+ case AF_INET6:
+ qp = qbuf;
+ for (n = IN6ADDRSZ - 1; n >= 0; n--)
+ qp += sprintf (qp, "%x.%x.", uaddr[n] & 0xf, (uaddr[n] >> 4) & 0xf);
+ strcpy(qp, "ip6.int");
+ break;
+ default:
+ /* Cannot happen. */
+ }
+
+ n = res_query (qbuf, C_IN, T_PTR, (u_char *)host_buffer.buf,
+ sizeof host_buffer);
+ if (n < 0)
+ return errno == ECONNREFUSED ? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND;
+
+ status = getanswer_r (&host_buffer, n, qbuf, T_PTR, result, buffer, buflen,
+ h_errnop);
+ if (status != NSS_STATUS_SUCCESS)
+ return status;
+
+#ifdef SUNSECURITY
+ This is not implemented because it is not possible to use the current
+ source from bind in a multi-threaded program.
+#endif
+
+ result->h_addrtype = af;
+ result->h_length = len;
+ bcopy (addr, host_data->host_addr, len);
+ host_data->h_addr_ptrs[0] = (char *) host_data->host_addr;
+ host_data->h_addr_ptrs[1] = NULL;
+ if (af == AF_INET && (_res.options & RES_USE_INET6))
+ {
+ map_v4v6_address ((char *) host_data->host_addr,
+ (char *) host_data->host_addr);
+ result->h_addrtype = AF_INET6;
+ result->h_length = IN6ADDRSZ;
+ }
+ *h_errnop = NETDB_SUCCESS;
+ return NSS_STATUS_SUCCESS;
+}
+
+
+static enum nss_status
+getanswer_r (const querybuf *answer, int anslen, const char *qname, int qtype,
+ struct hostent *result, char *buffer, int buflen, int *h_errnop)
+{
+ struct host_data
+ {
+ char *aliases[MAX_NR_ALIASES];
+ unsigned char host_addr[16]; /* IPv4 or IPv6 */
+ char *h_addr_ptrs[MAX_NR_ADDRS + 1];
+ char linebuffer[0];
+ } *host_data = (struct host_data *) buffer;
+ int linebuflen = buflen - offsetof (struct host_data, linebuffer);
+ register const HEADER *hp;
+ const u_char *end_of_message, *cp;
+ int n, ancount, qdcount;
+ int haveanswer, had_error;
+ char *bp, **ap, **hap;
+ char tbuf[MAXDNAME+1];
+ const char *tname;
+ int (*name_ok) __P ((const char *));
+
+ tname = qname;
+ result->h_name = NULL;
+ end_of_message = answer->buf + anslen;
+ switch (qtype)
+ {
+ case T_A:
+ case T_AAAA:
+ name_ok = res_hnok;
+ break;
+ case T_PTR:
+ name_ok = res_dnok;
+ break;
+ default:
+ return NSS_STATUS_UNAVAIL; /* XXX should be abort(); */
+ }
+
+ /*
+ * find first satisfactory answer
+ */
+ hp = &answer->hdr;
+ bp = host_data->linebuffer;
+ ancount = ntohs (hp->ancount);
+ qdcount = ntohs (hp->qdcount);
+ cp = answer->buf + HFIXEDSZ;
+ if (qdcount != 1)
+ {
+ *h_errnop = NO_RECOVERY;
+ return NSS_STATUS_UNAVAIL;
+ }
+
+ n = dn_expand (answer->buf, end_of_message, cp, bp, linebuflen);
+ if (n < 0 || (*name_ok) (bp) == 0)
+ {
+ *h_errnop = NO_RECOVERY;
+ return NSS_STATUS_UNAVAIL;
+ }
+ cp += n + QFIXEDSZ;
+
+ if (qtype == T_A || qtype == T_AAAA)
+ {
+ /* res_send() has already verified that the query name is the
+ * same as the one we sent; this just gets the expanded name
+ * (i.e., with the succeeding search-domain tacked on).
+ */
+ n = strlen (bp) + 1; /* for the \0 */
+ result->h_name = bp;
+ bp += n;
+ linebuflen -= n;
+ /* The qname can be abbreviated, but h_name is now absolute. */
+ qname = result->h_name;
+ }
+
+ ap = host_data->aliases;
+ *ap = NULL;
+ result->h_aliases = host_data->aliases;
+ hap = host_data->h_addr_ptrs;
+ *hap = NULL;
+ result->h_addr_list = host_data->h_addr_ptrs;
+ haveanswer = 0;
+ had_error = 0;
+
+ while (ancount-- > 0 && cp < end_of_message && had_error == 0)
+ {
+ int type, class;
+
+ n = dn_expand (answer->buf, end_of_message, cp, bp, linebuflen);
+ if (n < 0 || (*name_ok) (bp) == 0)
+ {
+ ++had_error;
+ continue;
+ }
+ cp += n; /* name */
+ type = _getshort (cp);
+ cp += INT16SZ; /* type */
+ class = _getshort(cp);
+ cp += INT16SZ + INT32SZ; /* class, TTL */
+ n = _getshort(cp);
+ cp += INT16SZ; /* len */
+ if (class != C_IN)
+ {
+ /* XXX - debug? syslog? */
+ cp += n;
+ continue; /* XXX - had_error++ ? */
+ }
+
+ if ((qtype ==T_A || qtype == T_AAAA) && type == T_CNAME)
+ {
+ if (ap >= &host_data->aliases[MAX_NR_ALIASES - 1])
+ continue;
+ n = dn_expand (answer->buf, end_of_message, cp, tbuf, sizeof tbuf);
+ if (n < 0 || (*name_ok) (tbuf) == 0)
+ {
+ ++had_error;
+ continue;
+ }
+ cp += n;
+ /* Store alias. */
+ *ap++ = bp;
+ n = strlen (bp) + 1; /* For the \0. */
+ bp += n;
+ linebuflen -= n;
+ /* Get canonical name. */
+ n = strlen (tbuf) + 1; /* For the \0. */
+ if (n > buflen)
+ {
+ ++had_error;
+ continue;
+ }
+ strcpy (bp, tbuf);
+ result->h_name = bp;
+ bp += n;
+ linebuflen -= n;
+ continue;
+ }
+
+ if (qtype == T_PTR && type == T_CNAME)
+ {
+ n = dn_expand (answer->buf, end_of_message, cp, tbuf, sizeof tbuf);
+ if (n < 0 || res_hnok (tbuf) == 0)
+ {
+ ++had_error;
+ continue;
+ }
+ cp += n;
+ /* Get canonical name. */
+ n = strlen (tbuf) + 1; /* For the \0. */
+ if (n > buflen)
+ {
+ ++had_error;
+ continue;
+ }
+ strcpy (bp, tbuf);
+ tname = bp;
+ bp += n;
+ linebuflen -= n;
+ continue;
+ }
+ if (type != qtype)
+ {
+ syslog (LOG_NOTICE | LOG_AUTH,
+ "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
+ qname, p_class (C_IN), p_type (qtype), p_type (type));
+ cp += n;
+ continue; /* XXX - had_error++ ? */
+ }
+
+ switch (type)
+ {
+ case T_PTR:
+ if (strcasecmp (tname, bp) != 0)
+ {
+ syslog (LOG_NOTICE | LOG_AUTH, AskedForGot, qname, bp);
+ cp += n;
+ continue; /* XXX - had_error++ ? */
+ }
+ n = dn_expand (answer->buf, end_of_message, cp, bp, linebuflen);
+ if (n < 0 || res_hnok (bp) == 0)
+ {
+ ++had_error;
+ break;
+ }
+#if MULTI_PTRS_ARE_ALIASES
+ cp += n;
+ if (haveanswer == 0)
+ result->h_name = bp;
+ else if (ap < &host_data->aliases[MAXALIASES-1])
+ *ap++ = bp;
+ else
+ n = -1;
+ if (n != -1)
+ {
+ n = strlen (bp) + 1; /* for the \0 */
+ bp += n;
+ linebuflen -= n;
+ }
+ break;
+#else
+ result->h_name = bp;
+ if (_res.options & RES_USE_INET6)
+ {
+ n = strlen (bp) + 1; /* for the \0 */
+ bp += n;
+ linebuflen -= n;
+ map_v4v6_hostent (result, &bp, &linebuflen);
+ }
+ *h_errnop = NETDB_SUCCESS;
+ return NSS_STATUS_SUCCESS;
+#endif
+ case T_A:
+ case T_AAAA:
+ if (strcasecmp (result->h_name, bp) != 0)
+ {
+ syslog (LOG_NOTICE | LOG_AUTH, AskedForGot, result->h_name, bp);
+ cp += n;
+ continue; /* XXX - had_error++ ? */
+ }
+ if (haveanswer)
+ {
+ if (n != result->h_length)
+ {
+ cp += n;
+ continue;
+ }
+ }
+ else
+ {
+ register int nn;
+
+ result->h_name = bp;
+ nn = strlen (bp) + 1; /* for the \0 */
+ bp += nn;
+ linebuflen -= nn;
+ }
+
+ bp += sizeof (align) - ((u_long) bp % sizeof (align));
+
+ if (n >= linebuflen)
+ {
+ ++had_error;
+ continue;
+ }
+ if (hap >= &host_data->h_addr_ptrs[MAX_NR_ADDRS-1])
+ {
+ cp += n;
+ continue;
+ }
+ bcopy (cp, *hap++ = bp, n);
+ bp += n;
+ cp += n;
+ linebuflen -= n;
+ break;
+ default:
+ abort ();
+ }
+ if (had_error == 0)
+ ++haveanswer;
+ }
+
+ if (haveanswer > 0)
+ {
+ *ap = NULL;
+ *hap = NULL;
+#if defined(RESOLVSORT)
+ /*
+ * Note: we sort even if host can take only one address
+ * in its return structures - should give it the "best"
+ * address in that case, not some random one
+ */
+ if (_res.nsort && haveanswer > 1 && qtype == T_A)
+ addrsort (host_data->h_addr_ptrs, haveanswer);
+#endif /*RESOLVSORT*/
+
+ if (result->h_name == NULL)
+ {
+ n = strlen (qname) + 1; /* For the \0. */
+ if (n > linebuflen)
+ goto try_again;
+ strcpy (bp, qname);
+ result->h_name = bp;
+ bp += n;
+ linebuflen -= n;
+ }
+
+ if (_res.options & RES_USE_INET6)
+ map_v4v6_hostent (result, &bp, &linebuflen);
+ *h_errnop = NETDB_SUCCESS;
+ return NSS_STATUS_SUCCESS;
+ }
+try_again:
+ *h_errnop = TRY_AGAIN;
+ return NSS_STATUS_TRYAGAIN;
+}
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