+/* Resolver state initialization and resolv.conf parsing.
+ Copyright (C) 1995-2019 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library 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.
+
+ 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
/*
* Copyright (c) 1985, 1989, 1993
* The Regents of the University of California. All rights reserved.
* SOFTWARE.
*/
-#if defined(LIBC_SCCS) && !defined(lint)
-static const char sccsid[] = "@(#)res_init.c 8.1 (Berkeley) 6/7/93";
-static const char rcsid[] = "$BINDId: res_init.c,v 8.16 2000/05/09 07:10:12 vixie Exp $";
-#endif /* LIBC_SCCS and not lint */
-
-#include <sys/types.h>
-#include <sys/param.h>
-#include <sys/socket.h>
-#include <sys/time.h>
-
-#include <netinet/in.h>
-#include <arpa/inet.h>
-#include <arpa/nameser.h>
-
#include <ctype.h>
-#include <resolv.h>
+#include <netdb.h>
+#include <resolv/resolv-internal.h>
+#include <res_hconf.h>
#include <stdio.h>
#include <stdio_ext.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
+#include <stdint.h>
+#include <arpa/inet.h>
+#include <arpa/nameser.h>
+#include <net/if.h>
+#include <netinet/in.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <inet/net-internal.h>
+#include <errno.h>
+#include <resolv_conf.h>
-#include <not-cancel.h>
+static uint32_t net_mask (struct in_addr);
-/* Options. Should all be left alone. */
-#define RESOLVSORT
-#define RFC1535
-/* #undef DEBUG */
+int
+res_ninit (res_state statp)
+{
+ return __res_vinit (statp, 0);
+}
+libc_hidden_def (__res_ninit)
-static void res_setoptions (res_state, const char *, const char *)
- internal_function;
+/* Return true if CH separates the netmask in the "sortlist"
+ directive. */
+static inline bool
+is_sort_mask (char ch)
+{
+ return ch == '/' || ch == '&';
+}
-#ifdef RESOLVSORT
-static const char sort_mask_chars[] = "/&";
-#define ISSORTMASK(ch) (strchr(sort_mask_chars, ch) != NULL)
-static u_int32_t net_mask __P((struct in_addr));
-#endif
+/* Array of name server addresses. */
+#define DYNARRAY_STRUCT nameserver_list
+#define DYNARRAY_ELEMENT const struct sockaddr *
+#define DYNARRAY_ELEMENT_FREE(e) free ((struct sockaddr *) *(e))
+#define DYNARRAY_INITIAL_SIZE 3
+#define DYNARRAY_PREFIX nameserver_list_
+#include <malloc/dynarray-skeleton.c>
+
+/* Array of strings for the search array. The backing store is
+ managed separately. */
+#define DYNARRAY_STRUCT search_list
+#define DYNARRAY_ELEMENT const char *
+#define DYNARRAY_INITIAL_SIZE 6
+#define DYNARRAY_PREFIX search_list_
+#include <malloc/dynarray-skeleton.c>
+
+/* Array of name server addresses. */
+#define DYNARRAY_STRUCT sort_list
+#define DYNARRAY_ELEMENT struct resolv_sortlist_entry
+#define DYNARRAY_INITIAL_SIZE 0
+#define DYNARRAY_PREFIX sort_list_
+#include <malloc/dynarray-skeleton.c>
+
+/* resolv.conf parser state and results. */
+struct resolv_conf_parser
+{
+ char *buffer; /* Temporary buffer for reading lines. */
-#if !defined(isascii) /* XXX - could be a function */
-# define isascii(c) (!(c & 0200))
-#endif
+ struct nameserver_list nameserver_list; /* Nameserver addresses. */
-/*
- * Resolver state default settings.
- */
+ char *search_list_store; /* Backing storage for search list entries. */
+ struct search_list search_list; /* Points into search_list_store. */
-/*
- * Set up default settings. If the configuration file exist, the values
- * there will have precedence. Otherwise, the server address is set to
- * INADDR_ANY and the default domain name comes from the gethostname().
- *
- * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1
- * rather than INADDR_ANY ("0.0.0.0") as the default name server address
- * since it was noted that INADDR_ANY actually meant ``the first interface
- * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,
- * it had to be "up" in order for you to reach your own name server. It
- * was later decided that since the recommended practice is to always
- * install local static routes through 127.0.0.1 for all your network
- * interfaces, that we could solve this problem without a code change.
- *
- * The configuration file should always be used, since it is the only way
- * to specify a default domain. If you are running a server on your local
- * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"
- * in the configuration file.
- *
- * Return 0 if completes successfully, -1 on error
- */
-int
-res_ninit(res_state statp) {
- extern int __res_vinit(res_state, int);
+ struct sort_list sort_list; /* Address preference sorting list. */
+
+ /* Configuration template. The non-array elements are filled in
+ directly. The array elements are updated prior to the call to
+ __resolv_conf_attach. */
+ struct resolv_conf template;
+};
- return (__res_vinit(statp, 0));
+/* Return true if *PREINIT contains actual preinitialization. */
+static bool
+has_preinit_values (const struct __res_state *preinit)
+{
+ return (preinit->retrans != 0 && preinit->retrans != RES_TIMEOUT)
+ || (preinit->retry != 0 && preinit->retry != RES_DFLRETRY)
+ || (preinit->options != 0
+ && (preinit->options & ~RES_INIT) != RES_DEFAULT);
}
-#ifdef _LIBC
-libc_hidden_def (__res_ninit)
-#endif
-/* This function has to be reachable by res_data.c but not publically. */
-int
-__res_vinit(res_state statp, int preinit) {
- register FILE *fp;
- register char *cp, **pp;
- register int n;
- char buf[BUFSIZ];
- int nserv = 0; /* number of nameserver records read from file */
-#ifdef _LIBC
- int nservall = 0; /* number of NS records read, nserv IPv4 only */
-#endif
- int haveenv = 0;
- int havesearch = 0;
-#ifdef RESOLVSORT
- int nsort = 0;
- char *net;
-#endif
-#ifndef RFC1535
- int dots;
-#endif
-
- if (!preinit) {
- statp->retrans = RES_TIMEOUT;
- statp->retry = RES_DFLRETRY;
- statp->options = RES_DEFAULT;
- statp->id = res_randomid();
- }
-
-#ifdef USELOOPBACK
- statp->nsaddr.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1);
-#else
- statp->nsaddr.sin_addr.s_addr = INADDR_ANY;
-#endif
- statp->nsaddr.sin_family = AF_INET;
- statp->nsaddr.sin_port = htons(NAMESERVER_PORT);
- statp->nscount = 1;
- statp->ndots = 1;
- statp->pfcode = 0;
- statp->_vcsock = -1;
- statp->_flags = 0;
- statp->qhook = NULL;
- statp->rhook = NULL;
- statp->_u._ext.nsinit = 0;
- statp->_u._ext.nscount = 0;
-#ifdef _LIBC
- statp->_u._ext.nscount6 = 0;
- for (n = 0; n < MAXNS; n++) {
- statp->_u._ext.nsaddrs[n] = NULL;
- statp->_u._ext.nsmap[n] = MAXNS;
- }
-#endif
-
- /* Allow user to override the local domain definition */
- if ((cp = getenv("LOCALDOMAIN")) != NULL) {
- (void)strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
- statp->defdname[sizeof(statp->defdname) - 1] = '\0';
- haveenv++;
-
- /*
- * Set search list to be blank-separated strings
- * from rest of env value. Permits users of LOCALDOMAIN
- * to still have a search list, and anyone to set the
- * one that they want to use as an individual (even more
- * important now that the rfc1535 stuff restricts searches)
- */
- cp = statp->defdname;
- pp = statp->dnsrch;
- *pp++ = cp;
- for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
- if (*cp == '\n') /* silly backwards compat */
- break;
- else if (*cp == ' ' || *cp == '\t') {
- *cp = 0;
- n = 1;
- } else if (n) {
- *pp++ = cp;
- n = 0;
- havesearch = 1;
- }
- }
- /* null terminate last domain if there are excess */
- while (*cp != '\0' && *cp != ' ' && *cp != '\t' && *cp != '\n')
- cp++;
- *cp = '\0';
- *pp++ = 0;
- }
-
-#define MATCH(line, name) \
- (!strncmp(line, name, sizeof(name) - 1) && \
- (line[sizeof(name) - 1] == ' ' || \
- line[sizeof(name) - 1] == '\t'))
-
- if ((fp = fopen(_PATH_RESCONF, "rc")) != NULL) {
- /* No threads use this stream. */
- __fsetlocking (fp, FSETLOCKING_BYCALLER);
- /* read the config file */
- while (fgets_unlocked(buf, sizeof(buf), fp) != NULL) {
- /* skip comments */
- if (*buf == ';' || *buf == '#')
- continue;
- /* read default domain name */
- if (MATCH(buf, "domain")) {
- if (haveenv) /* skip if have from environ */
- continue;
- cp = buf + sizeof("domain") - 1;
- while (*cp == ' ' || *cp == '\t')
- cp++;
- if ((*cp == '\0') || (*cp == '\n'))
- continue;
- strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
- statp->defdname[sizeof(statp->defdname) - 1] = '\0';
- if ((cp = strpbrk(statp->defdname, " \t\n")) != NULL)
- *cp = '\0';
- havesearch = 0;
- continue;
- }
- /* set search list */
- if (MATCH(buf, "search")) {
- if (haveenv) /* skip if have from environ */
- continue;
- cp = buf + sizeof("search") - 1;
- while (*cp == ' ' || *cp == '\t')
- cp++;
- if ((*cp == '\0') || (*cp == '\n'))
- continue;
- strncpy(statp->defdname, cp, sizeof(statp->defdname) - 1);
- statp->defdname[sizeof(statp->defdname) - 1] = '\0';
- if ((cp = strchr(statp->defdname, '\n')) != NULL)
- *cp = '\0';
- /*
- * Set search list to be blank-separated strings
- * on rest of line.
- */
- cp = statp->defdname;
- pp = statp->dnsrch;
- *pp++ = cp;
- for (n = 0; *cp && pp < statp->dnsrch + MAXDNSRCH; cp++) {
- if (*cp == ' ' || *cp == '\t') {
- *cp = 0;
- n = 1;
- } else if (n) {
- *pp++ = cp;
- n = 0;
- }
- }
- /* null terminate last domain if there are excess */
- while (*cp != '\0' && *cp != ' ' && *cp != '\t')
- cp++;
- *cp = '\0';
- *pp++ = 0;
- havesearch = 1;
- continue;
- }
- /* read nameservers to query */
-#ifdef _LIBC
- if (MATCH(buf, "nameserver") && nservall < MAXNS) {
-#else
- if (MATCH(buf, "nameserver") && nserv < MAXNS) {
-#endif
- struct in_addr a;
-
- cp = buf + sizeof("nameserver") - 1;
- while (*cp == ' ' || *cp == '\t')
- cp++;
- if ((*cp != '\0') && (*cp != '\n')
- && __inet_aton(cp, &a)) {
- statp->nsaddr_list[nserv].sin_addr = a;
- statp->nsaddr_list[nserv].sin_family = AF_INET;
- statp->nsaddr_list[nserv].sin_port =
- htons(NAMESERVER_PORT);
- nserv++;
-#ifdef _LIBC
- nservall++;
- } else {
- struct in6_addr a6;
- char *el;
-
- if ((el = strchr(cp, '\n')) != NULL)
- *el = '\0';
- if ((*cp != '\0') &&
- (inet_pton(AF_INET6, cp, &a6) > 0)) {
- struct sockaddr_in6 *sa6;
-
- sa6 = malloc(sizeof(*sa6));
- if (sa6 != NULL) {
- sa6->sin6_addr = a6;
- sa6->sin6_family = AF_INET6;
- sa6->sin6_port = htons(NAMESERVER_PORT);
- statp->_u._ext.nsaddrs[nservall] = sa6;
- statp->_u._ext.nssocks[nservall] = -1;
- statp->_u._ext.nsmap[nservall] = MAXNS + 1;
- nservall++;
- }
- }
-#endif
- }
- continue;
- }
-#ifdef RESOLVSORT
- if (MATCH(buf, "sortlist")) {
- struct in_addr a;
-
- cp = buf + sizeof("sortlist") - 1;
- while (nsort < MAXRESOLVSORT) {
- while (*cp == ' ' || *cp == '\t')
- cp++;
- if (*cp == '\0' || *cp == '\n' || *cp == ';')
- break;
- net = cp;
- while (*cp && !ISSORTMASK(*cp) && *cp != ';' &&
- isascii(*cp) && !isspace(*cp))
- cp++;
- n = *cp;
- *cp = 0;
- if (__inet_aton(net, &a)) {
- statp->sort_list[nsort].addr = a;
- if (ISSORTMASK(n)) {
- *cp++ = n;
- net = cp;
- while (*cp && *cp != ';' &&
- isascii(*cp) && !isspace(*cp))
- cp++;
- n = *cp;
- *cp = 0;
- if (__inet_aton(net, &a)) {
- statp->sort_list[nsort].mask = a.s_addr;
- } else {
- statp->sort_list[nsort].mask =
- net_mask(statp->sort_list[nsort].addr);
- }
- } else {
- statp->sort_list[nsort].mask =
- net_mask(statp->sort_list[nsort].addr);
- }
- nsort++;
- }
- *cp = n;
- }
- continue;
- }
-#endif
- if (MATCH(buf, "options")) {
- res_setoptions(statp, buf + sizeof("options") - 1, "conf");
- continue;
- }
- }
- if (nserv > 1)
- statp->nscount = nserv;
-#ifdef _LIBC
- if (nservall - nserv > 0)
- statp->_u._ext.nscount6 = nservall - nserv;
-#endif
-#ifdef RESOLVSORT
- statp->nsort = nsort;
-#endif
- (void) fclose(fp);
- }
- if (statp->defdname[0] == 0 &&
- __gethostname(buf, sizeof(statp->defdname) - 1) == 0 &&
- (cp = strchr(buf, '.')) != NULL)
- strcpy(statp->defdname, cp + 1);
-
- /* find components of local domain that might be searched */
- if (havesearch == 0) {
- pp = statp->dnsrch;
- *pp++ = statp->defdname;
- *pp = NULL;
-
-#ifndef RFC1535
- dots = 0;
- for (cp = statp->defdname; *cp; cp++)
- dots += (*cp == '.');
-
- cp = statp->defdname;
- while (pp < statp->dnsrch + MAXDFLSRCH) {
- if (dots < LOCALDOMAINPARTS)
- break;
- cp = __rawmemchr(cp, '.') + 1; /* we know there is one */
- *pp++ = cp;
- dots--;
- }
- *pp = NULL;
-#ifdef DEBUG
- if (statp->options & RES_DEBUG) {
- printf(";; res_init()... default dnsrch list:\n");
- for (pp = statp->dnsrch; *pp; pp++)
- printf(";;\t%s\n", *pp);
- printf(";;\t..END..\n");
- }
-#endif
-#endif /* !RFC1535 */
- }
-
- if ((cp = getenv("RES_OPTIONS")) != NULL)
- res_setoptions(statp, cp, "env");
- statp->options |= RES_INIT;
- return (0);
+static void
+resolv_conf_parser_init (struct resolv_conf_parser *parser,
+ const struct __res_state *preinit)
+{
+ parser->buffer = NULL;
+ parser->search_list_store = NULL;
+ nameserver_list_init (&parser->nameserver_list);
+ search_list_init (&parser->search_list);
+ sort_list_init (&parser->sort_list);
+
+ if (preinit != NULL)
+ {
+ parser->template.retrans = preinit->retrans;
+ parser->template.retry = preinit->retry;
+ parser->template.options = preinit->options | RES_INIT;
+ }
+ else
+ {
+ parser->template.retrans = RES_TIMEOUT;
+ parser->template.retry = RES_DFLRETRY;
+ parser->template.options = RES_DEFAULT | RES_INIT;
+ }
+ parser->template.ndots = 1;
}
static void
-internal_function
-res_setoptions(res_state statp, const char *options, const char *source) {
- const char *cp = options;
- int i;
-
-#ifdef DEBUG
- if (statp->options & RES_DEBUG)
- printf(";; res_setoptions(\"%s\", \"%s\")...\n",
- options, source);
-#endif
- while (*cp) {
- /* skip leading and inner runs of spaces */
- while (*cp == ' ' || *cp == '\t')
- cp++;
- /* search for and process individual options */
- if (!strncmp(cp, "ndots:", sizeof("ndots:") - 1)) {
- i = atoi(cp + sizeof("ndots:") - 1);
- if (i <= RES_MAXNDOTS)
- statp->ndots = i;
- else
- statp->ndots = RES_MAXNDOTS;
-#ifdef DEBUG
- if (statp->options & RES_DEBUG)
- printf(";;\tndots=%d\n", statp->ndots);
-#endif
- } else if (!strncmp(cp, "timeout:", sizeof("timeout:") - 1)) {
- i = atoi(cp + sizeof("timeout:") - 1);
- if (i <= RES_MAXRETRANS)
- statp->retrans = i;
- else
- statp->retrans = RES_MAXRETRANS;
- } else if (!strncmp(cp, "attempts:", sizeof("attempts:") - 1)){
- i = atoi(cp + sizeof("attempts:") - 1);
- if (i <= RES_MAXRETRY)
- statp->retry = i;
- else
- statp->retry = RES_MAXRETRY;
- } else if (!strncmp(cp, "debug", sizeof("debug") - 1)) {
-#ifdef DEBUG
- if (!(statp->options & RES_DEBUG)) {
- printf(";; res_setoptions(\"%s\", \"%s\")..\n",
- options, source);
- statp->options |= RES_DEBUG;
- }
- printf(";;\tdebug\n");
-#endif
- } else if (!strncmp(cp, "inet6", sizeof("inet6") - 1)) {
- statp->options |= RES_USE_INET6;
- } else if (!strncmp(cp, "ip6-bytestring",
- sizeof("ip6-bytestring") - 1)) {
- statp->options |= RES_USEBSTRING;
- } else if (!strncmp(cp, "rotate", sizeof("rotate") - 1)) {
- statp->options |= RES_ROTATE;
- } else if (!strncmp(cp, "no-check-names",
- sizeof("no-check-names") - 1)) {
- statp->options |= RES_NOCHECKNAME;
- } else {
- /* XXX - print a warning here? */
- }
- /* skip to next run of spaces */
- while (*cp && *cp != ' ' && *cp != '\t')
- cp++;
- }
+resolv_conf_parser_free (struct resolv_conf_parser *parser)
+{
+ free (parser->buffer);
+ free (parser->search_list_store);
+ nameserver_list_free (&parser->nameserver_list);
+ search_list_free (&parser->search_list);
+ sort_list_free (&parser->sort_list);
}
-#ifdef RESOLVSORT
-/* XXX - should really support CIDR which means explicit masks always. */
-static u_int32_t
-net_mask(in) /* XXX - should really use system's version of this */
- struct in_addr in;
+/* Allocate a struct sockaddr_in object on the heap, with the
+ specified address and port. */
+static struct sockaddr *
+allocate_address_v4 (struct in_addr a, uint16_t port)
{
- register u_int32_t i = ntohl(in.s_addr);
+ struct sockaddr_in *sa4 = malloc (sizeof (*sa4));
+ if (sa4 == NULL)
+ return NULL;
+ sa4->sin_family = AF_INET;
+ sa4->sin_addr = a;
+ sa4->sin_port = htons (port);
+ return (struct sockaddr *) sa4;
+}
- if (IN_CLASSA(i))
- return (htonl(IN_CLASSA_NET));
- else if (IN_CLASSB(i))
- return (htonl(IN_CLASSB_NET));
- return (htonl(IN_CLASSC_NET));
+/* Try to obtain the domain name from the host name and store it in
+ *RESULT. Return false on memory allocation failure. If the domain
+ name cannot be determined for any other reason, write NULL to
+ *RESULT and return true. */
+static bool
+domain_from_hostname (char **result)
+{
+ char buf[256];
+ /* gethostbyname may not terminate the buffer. */
+ buf[sizeof (buf) - 1] = '\0';
+ if (__gethostname (buf, sizeof (buf) - 1) == 0)
+ {
+ char *dot = strchr (buf, '.');
+ if (dot != NULL)
+ {
+ *result = __strdup (dot + 1);
+ if (*result == NULL)
+ return false;
+ return true;
+ }
+ }
+ *result = NULL;
+ return true;
}
-#endif
-u_int
-res_randomid(void) {
- struct timeval now;
+static void res_setoptions (struct resolv_conf_parser *, const char *options);
- __gettimeofday(&now, NULL);
- return (0xffff & (now.tv_sec ^ now.tv_usec ^ __getpid()));
+/* Internal helper function for __res_vinit, to aid with resource
+ deallocation and error handling. Return true on success, false on
+ failure. */
+static bool
+res_vinit_1 (FILE *fp, struct resolv_conf_parser *parser)
+{
+ char *cp;
+ size_t buffer_size = 0;
+ bool haveenv = false;
+
+ /* Allow user to override the local domain definition. */
+ if ((cp = getenv ("LOCALDOMAIN")) != NULL)
+ {
+ /* The code below splits the string in place. */
+ cp = __strdup (cp);
+ if (cp == NULL)
+ return false;
+ free (parser->search_list_store);
+ parser->search_list_store = cp;
+ haveenv = true;
+
+ /* The string will be truncated as needed below. */
+ search_list_add (&parser->search_list, cp);
+
+ /* Set search list to be blank-separated strings from rest of
+ env value. Permits users of LOCALDOMAIN to still have a
+ search list, and anyone to set the one that they want to use
+ as an individual (even more important now that the rfc1535
+ stuff restricts searches). */
+ for (bool in_name = true; *cp != '\0'; cp++)
+ {
+ if (*cp == '\n')
+ {
+ *cp = '\0';
+ break;
+ }
+ else if (*cp == ' ' || *cp == '\t')
+ {
+ *cp = '\0';
+ in_name = false;
+ }
+ else if (!in_name)
+ {
+ search_list_add (&parser->search_list, cp);
+ in_name = true;
+ }
+ }
+ }
+
+#define MATCH(line, name) \
+ (!strncmp ((line), name, sizeof (name) - 1) \
+ && ((line)[sizeof (name) - 1] == ' ' \
+ || (line)[sizeof (name) - 1] == '\t'))
+
+ if (fp != NULL)
+ {
+ /* No threads use this stream. */
+ __fsetlocking (fp, FSETLOCKING_BYCALLER);
+ /* Read the config file. */
+ while (true)
+ {
+ {
+ ssize_t ret = __getline (&parser->buffer, &buffer_size, fp);
+ if (ret <= 0)
+ {
+ if (_IO_ferror_unlocked (fp))
+ return false;
+ else
+ break;
+ }
+ }
+
+ /* Skip comments. */
+ if (*parser->buffer == ';' || *parser->buffer == '#')
+ continue;
+ /* Read default domain name. */
+ if (MATCH (parser->buffer, "domain"))
+ {
+ if (haveenv)
+ /* LOCALDOMAIN overrides the configuration file. */
+ continue;
+ cp = parser->buffer + sizeof ("domain") - 1;
+ while (*cp == ' ' || *cp == '\t')
+ cp++;
+ if ((*cp == '\0') || (*cp == '\n'))
+ continue;
+
+ cp = __strdup (cp);
+ if (cp == NULL)
+ return false;
+ free (parser->search_list_store);
+ parser->search_list_store = cp;
+ search_list_clear (&parser->search_list);
+ search_list_add (&parser->search_list, cp);
+ /* Replace trailing whitespace. */
+ if ((cp = strpbrk (cp, " \t\n")) != NULL)
+ *cp = '\0';
+ continue;
+ }
+ /* Set search list. */
+ if (MATCH (parser->buffer, "search"))
+ {
+ if (haveenv)
+ /* LOCALDOMAIN overrides the configuration file. */
+ continue;
+ cp = parser->buffer + sizeof ("search") - 1;
+ while (*cp == ' ' || *cp == '\t')
+ cp++;
+ if ((*cp == '\0') || (*cp == '\n'))
+ continue;
+
+ {
+ char *p = strchr (cp, '\n');
+ if (p != NULL)
+ *p = '\0';
+ }
+ cp = __strdup (cp);
+ if (cp == NULL)
+ return false;
+ free (parser->search_list_store);
+ parser->search_list_store = cp;
+
+ /* The string is truncated below. */
+ search_list_clear (&parser->search_list);
+ search_list_add (&parser->search_list, cp);
+
+ /* Set search list to be blank-separated strings on rest
+ of line. */
+ for (bool in_name = true; *cp != '\0'; cp++)
+ {
+ if (*cp == ' ' || *cp == '\t')
+ {
+ *cp = '\0';
+ in_name = false;
+ }
+ else if (!in_name)
+ {
+ search_list_add (&parser->search_list, cp);
+ in_name = true;
+ }
+ }
+ continue;
+ }
+ /* Read nameservers to query. */
+ if (MATCH (parser->buffer, "nameserver"))
+ {
+ struct in_addr a;
+
+ cp = parser->buffer + sizeof ("nameserver") - 1;
+ while (*cp == ' ' || *cp == '\t')
+ cp++;
+
+ /* Ignore trailing contents on the name server line. */
+ {
+ char *el;
+ if ((el = strpbrk (cp, " \t\n")) != NULL)
+ *el = '\0';
+ }
+
+ struct sockaddr *sa;
+ if ((*cp != '\0') && (*cp != '\n') && __inet_aton_exact (cp, &a))
+ {
+ sa = allocate_address_v4 (a, NAMESERVER_PORT);
+ if (sa == NULL)
+ return false;
+ }
+ else
+ {
+ struct in6_addr a6;
+ char *el;
+ if ((el = strchr (cp, SCOPE_DELIMITER)) != NULL)
+ *el = '\0';
+ if ((*cp != '\0') && (__inet_pton (AF_INET6, cp, &a6) > 0))
+ {
+ struct sockaddr_in6 *sa6;
+
+ sa6 = malloc (sizeof (*sa6));
+ if (sa6 == NULL)
+ return false;
+
+ sa6->sin6_family = AF_INET6;
+ sa6->sin6_port = htons (NAMESERVER_PORT);
+ sa6->sin6_flowinfo = 0;
+ sa6->sin6_addr = a6;
+
+ sa6->sin6_scope_id = 0;
+ if (__glibc_likely (el != NULL))
+ /* Ignore errors, for backwards
+ compatibility. */
+ __inet6_scopeid_pton
+ (&a6, el + 1, &sa6->sin6_scope_id);
+ sa = (struct sockaddr *) sa6;
+ }
+ else
+ /* IPv6 address parse failure. */
+ sa = NULL;
+ }
+ if (sa != NULL)
+ {
+ const struct sockaddr **p = nameserver_list_emplace
+ (&parser->nameserver_list);
+ if (p != NULL)
+ *p = sa;
+ else
+ {
+ free (sa);
+ return false;
+ }
+ }
+ continue;
+ }
+ if (MATCH (parser->buffer, "sortlist"))
+ {
+ struct in_addr a;
+
+ cp = parser->buffer + sizeof ("sortlist") - 1;
+ while (true)
+ {
+ while (*cp == ' ' || *cp == '\t')
+ cp++;
+ if (*cp == '\0' || *cp == '\n' || *cp == ';')
+ break;
+ char *net = cp;
+ while (*cp && !is_sort_mask (*cp) && *cp != ';'
+ && isascii (*cp) && !isspace (*cp))
+ cp++;
+ char separator = *cp;
+ *cp = 0;
+ struct resolv_sortlist_entry e;
+ if (__inet_aton_exact (net, &a))
+ {
+ e.addr = a;
+ if (is_sort_mask (separator))
+ {
+ *cp++ = separator;
+ net = cp;
+ while (*cp && *cp != ';'
+ && isascii (*cp) && !isspace (*cp))
+ cp++;
+ separator = *cp;
+ *cp = 0;
+ if (__inet_aton_exact (net, &a))
+ e.mask = a.s_addr;
+ else
+ e.mask = net_mask (e.addr);
+ }
+ else
+ e.mask = net_mask (e.addr);
+ sort_list_add (&parser->sort_list, e);
+ }
+ *cp = separator;
+ }
+ continue;
+ }
+ if (MATCH (parser->buffer, "options"))
+ {
+ res_setoptions (parser, parser->buffer + sizeof ("options") - 1);
+ continue;
+ }
+ }
+ fclose (fp);
+ }
+ if (__glibc_unlikely (nameserver_list_size (&parser->nameserver_list) == 0))
+ {
+ const struct sockaddr **p
+ = nameserver_list_emplace (&parser->nameserver_list);
+ if (p == NULL)
+ return false;
+ *p = allocate_address_v4 (__inet_makeaddr (IN_LOOPBACKNET, 1),
+ NAMESERVER_PORT);
+ if (*p == NULL)
+ return false;
+ }
+
+ if (search_list_size (&parser->search_list) == 0)
+ {
+ char *domain;
+ if (!domain_from_hostname (&domain))
+ return false;
+ if (domain != NULL)
+ {
+ free (parser->search_list_store);
+ parser->search_list_store = domain;
+ search_list_add (&parser->search_list, domain);
+ }
+ }
+
+ if ((cp = getenv ("RES_OPTIONS")) != NULL)
+ res_setoptions (parser, cp);
+
+ if (nameserver_list_has_failed (&parser->nameserver_list)
+ || search_list_has_failed (&parser->search_list)
+ || sort_list_has_failed (&parser->sort_list))
+ {
+ __set_errno (ENOMEM);
+ return false;
+ }
+
+ return true;
}
-#ifdef _LIBC
-libc_hidden_def (__res_randomid)
-#endif
+struct resolv_conf *
+__resolv_conf_load (struct __res_state *preinit)
+{
+ /* Ensure that /etc/hosts.conf has been loaded (once). */
+ _res_hconf_init ();
+
+ FILE *fp = fopen (_PATH_RESCONF, "rce");
+ if (fp == NULL)
+ switch (errno)
+ {
+ case EACCES:
+ case EISDIR:
+ case ELOOP:
+ case ENOENT:
+ case ENOTDIR:
+ case EPERM:
+ /* Ignore these errors. They are persistent errors caused
+ by file system contents. */
+ break;
+ default:
+ /* Other errors refer to resource allocation problems and
+ need to be handled by the application. */
+ return NULL;
+ }
-/*
- * This routine is for closing the socket if a virtual circuit is used and
- * the program wants to close it. This provides support for endhostent()
- * which expects to close the socket.
- *
- * This routine is not expected to be user visible.
- */
-void
-res_nclose(res_state statp) {
- int ns;
-
- if (statp->_vcsock >= 0) {
- close_not_cancel_no_status(statp->_vcsock);
- statp->_vcsock = -1;
- statp->_flags &= ~(RES_F_VC | RES_F_CONN);
- }
-#ifdef _LIBC
- for (ns = 0; ns < MAXNS; ns++)
-#else
- for (ns = 0; ns < statp->_u._ext.nscount; ns++)
-#endif
- if (statp->_u._ext.nsaddrs[ns]
- && statp->_u._ext.nssocks[ns] != -1) {
- close_not_cancel_no_status(statp->_u._ext.nssocks[ns]);
- statp->_u._ext.nssocks[ns] = -1;
- }
- statp->_u._ext.nsinit = 0;
+ struct resolv_conf_parser parser;
+ resolv_conf_parser_init (&parser, preinit);
+
+ struct resolv_conf *conf = NULL;
+ if (res_vinit_1 (fp, &parser))
+ {
+ parser.template.nameserver_list
+ = nameserver_list_begin (&parser.nameserver_list);
+ parser.template.nameserver_list_size
+ = nameserver_list_size (&parser.nameserver_list);
+ parser.template.search_list = search_list_begin (&parser.search_list);
+ parser.template.search_list_size
+ = search_list_size (&parser.search_list);
+ parser.template.sort_list = sort_list_begin (&parser.sort_list);
+ parser.template.sort_list_size = sort_list_size (&parser.sort_list);
+ conf = __resolv_conf_allocate (&parser.template);
+ }
+ resolv_conf_parser_free (&parser);
+
+ return conf;
+}
+
+/* Set up default settings. If the /etc/resolv.conf configuration
+ file exist, the values there will have precedence. Otherwise, the
+ server address is set to INADDR_LOOPBACK and the default domain
+ name comes from gethostname. The RES_OPTIONS and LOCALDOMAIN
+ environment variables can be used to override some settings.
+ Return 0 if completes successfully, -1 on error. */
+int
+__res_vinit (res_state statp, int preinit)
+{
+ struct resolv_conf *conf;
+ if (preinit && has_preinit_values (statp))
+ /* For the preinit case, we cannot use the cached configuration
+ because some settings could be different. */
+ conf = __resolv_conf_load (statp);
+ else
+ conf = __resolv_conf_get_current ();
+ if (conf == NULL)
+ return -1;
+
+ bool ok = __resolv_conf_attach (statp, conf);
+ __resolv_conf_put (conf);
+ if (ok)
+ {
+ if (preinit)
+ statp->id = res_randomid ();
+ return 0;
+ }
+ else
+ return -1;
}
-#ifdef _LIBC
-libc_hidden_def (__res_nclose)
-#endif
-
-#ifdef _LIBC
-# ifdef _LIBC_REENTRANT
-/* This is called when a thread is exiting to free resources held in _res. */
-static void __attribute__ ((section ("__libc_thread_freeres_fn")))
-res_thread_freeres (void)
+
+static void
+res_setoptions (struct resolv_conf_parser *parser, const char *options)
{
- if (_res.nscount == 0)
- /* Never called res_ninit. */
- return;
+ const char *cp = options;
+
+ while (*cp)
+ {
+ /* Skip leading and inner runs of spaces. */
+ while (*cp == ' ' || *cp == '\t')
+ cp++;
+ /* Search for and process individual options. */
+ if (!strncmp (cp, "ndots:", sizeof ("ndots:") - 1))
+ {
+ int i = atoi (cp + sizeof ("ndots:") - 1);
+ if (i <= RES_MAXNDOTS)
+ parser->template.ndots = i;
+ else
+ parser->template.ndots = RES_MAXNDOTS;
+ }
+ else if (!strncmp (cp, "timeout:", sizeof ("timeout:") - 1))
+ {
+ int i = atoi (cp + sizeof ("timeout:") - 1);
+ if (i <= RES_MAXRETRANS)
+ parser->template.retrans = i;
+ else
+ parser->template.retrans = RES_MAXRETRANS;
+ }
+ else if (!strncmp (cp, "attempts:", sizeof ("attempts:") - 1))
+ {
+ int i = atoi (cp + sizeof ("attempts:") - 1);
+ if (i <= RES_MAXRETRY)
+ parser->template.retry = i;
+ else
+ parser->template.retry = RES_MAXRETRY;
+ }
+ else
+ {
+ static const struct
+ {
+ char str[22];
+ uint8_t len;
+ uint8_t clear;
+ unsigned long int flag;
+ } options[] = {
+#define STRnLEN(str) str, sizeof (str) - 1
+ { STRnLEN ("rotate"), 0, RES_ROTATE },
+ { STRnLEN ("edns0"), 0, RES_USE_EDNS0 },
+ { STRnLEN ("single-request-reopen"), 0, RES_SNGLKUPREOP },
+ { STRnLEN ("single-request"), 0, RES_SNGLKUP },
+ { STRnLEN ("no_tld_query"), 0, RES_NOTLDQUERY },
+ { STRnLEN ("no-tld-query"), 0, RES_NOTLDQUERY },
+ { STRnLEN ("no-reload"), 0, RES_NORELOAD },
+ { STRnLEN ("use-vc"), 0, RES_USEVC }
+ };
+#define noptions (sizeof (options) / sizeof (options[0]))
+ for (int i = 0; i < noptions; ++i)
+ if (strncmp (cp, options[i].str, options[i].len) == 0)
+ {
+ if (options[i].clear)
+ parser->template.options &= options[i].flag;
+ else
+ parser->template.options |= options[i].flag;
+ break;
+ }
+ }
+ /* Skip to next run of spaces. */
+ while (*cp && *cp != ' ' && *cp != '\t')
+ cp++;
+ }
+}
- __res_nclose (&_res); /* Close any VC sockets. */
+static uint32_t
+net_mask (struct in_addr in)
+{
+ uint32_t i = ntohl (in.s_addr);
- for (int ns = 0; ns < MAXNS; ns++)
- if (_res._u._ext.nsaddrs[ns] != NULL)
- {
- free (_res._u._ext.nsaddrs[ns]);
- _res._u._ext.nsaddrs[ns] = NULL;
- }
+ if (IN_CLASSA (i))
+ return htonl (IN_CLASSA_NET);
+ else if (IN_CLASSB (i))
+ return htonl (IN_CLASSB_NET);
+ return htonl (IN_CLASSC_NET);
}
-text_set_element (__libc_thread_subfreeres, res_thread_freeres);
-text_set_element (__libc_subfreeres, res_thread_freeres);
-# endif
-#endif
projects / thirdparty / glibc.git / blobdiff