make the resolver stat resolv.conf and update if it changes.

useful feedback and ok deraadt@

10 files changed, 68 insertions, 34 deletions

diff --git a/lib/libc/net/getaddrinfo.c b/lib/libc/net/getaddrinfo.c
index c7cc0500c33..19967e84327 100644
--- a/lib/libc/net/getaddrinfo.c
+++ b/lib/libc/net/getaddrinfo.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: getaddrinfo.c,v 1.51 2005/03/25 13:24:12 otto Exp $	*/
+/*	$OpenBSD: getaddrinfo.c,v 1.52 2005/03/30 02:58:28 tedu Exp $	*/
 /*	$KAME: getaddrinfo.c,v 1.31 2000/08/31 17:36:43 itojun Exp $	*/
 
 /*
@@ -516,7 +516,7 @@ explore_fqdn(const struct addrinfo *pai, const char *hostname,
 		return 0;
 	}
 
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1)
+	if (_res_init(0) == -1)
 		strlcpy(lookups, "f", sizeof lookups);
 	else {
 		bcopy(_resp->lookups, lookups, sizeof lookups);
@@ -1525,7 +1525,7 @@ res_queryN(const char *name, struct res_target *target)
 	rcode = NOERROR;
 	ancount = 0;
 
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1) {
+	if (_res_init(0) == -1) {
 		h_errno = NETDB_INTERNAL;
 		free(buf);
 		return (-1);
@@ -1631,7 +1631,7 @@ res_searchN(const char *name, struct res_target *target)
 	int trailing_dot, ret, saved_herrno;
 	int got_nodata = 0, got_servfail = 0, tried_as_is = 0;
 
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1) {
+	if (_res_init(0) == -1) {
 		h_errno = NETDB_INTERNAL;
 		return (-1);
 	}
@@ -1768,7 +1768,7 @@ res_querydomainN(const char *name, const char *domain,
 	const char *longname = nbuf;
 	size_t n, d;
 
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1) {
+	if (_res_init(0) == -1) {
 		h_errno = NETDB_INTERNAL;
 		return (-1);
 	}
diff --git a/lib/libc/net/gethostnamadr.c b/lib/libc/net/gethostnamadr.c
index 0a42d0a27ea..c643f2382ae 100644
--- a/lib/libc/net/gethostnamadr.c
+++ b/lib/libc/net/gethostnamadr.c
@@ -48,7 +48,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static const char rcsid[] = "$OpenBSD: gethostnamadr.c,v 1.60 2004/07/29 03:09:40 itojun Exp $";
+static const char rcsid[] = "$OpenBSD: gethostnamadr.c,v 1.61 2005/03/30 02:58:28 tedu Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <sys/param.h>
@@ -479,7 +479,7 @@ gethostbyname(const char *name)
 	struct hostent *hp;
 	extern struct hostent *_gethtbyname2(const char *, int);
 
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1)
+	if (_res_init(0) == -1)
 		hp = _gethtbyname2(name, AF_INET);
 
 	else if (_resp->options & RES_USE_INET6) {
@@ -505,7 +505,7 @@ gethostbyname2(const char *name, int af)
 	extern struct hostent *_gethtbyname2(const char *, int);
 	extern struct hostent *_yp_gethtbyname(const char *);
 
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1)
+	if (_res_init(0) == -1)
 		return (_gethtbyname2(name, af));
 
 	switch (af) {
@@ -653,7 +653,7 @@ gethostbyaddr(const char *addr, int len, int af)
 	extern struct hostent *_gethtbyaddr(const char *, int, int);
 	extern struct hostent *_yp_gethtbyaddr(const char *);
 	
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1) {
+	if (_res_init(0) == -1) {
 		res = _gethtbyaddr(addr, len, af);
 		return (res);
 	}
diff --git a/lib/libc/net/getnetnamadr.c b/lib/libc/net/getnetnamadr.c
index 42410264b13..303ac2cc54a 100644
--- a/lib/libc/net/getnetnamadr.c
+++ b/lib/libc/net/getnetnamadr.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: getnetnamadr.c,v 1.24 2005/03/25 13:24:12 otto Exp $	*/
+/*	$OpenBSD: getnetnamadr.c,v 1.25 2005/03/30 02:58:28 tedu Exp $	*/
 
 /*
  * Copyright (c) 1997, Jason Downs.  All rights reserved.
@@ -66,7 +66,7 @@ static char sccsid[] = "@(#)getnetbyaddr.c	8.1 (Berkeley) 6/4/93";
 static char sccsid_[] = "from getnetnamadr.c	1.4 (Coimbra) 93/06/03";
 static char rcsid[] = "$From: getnetnamadr.c,v 8.7 1996/08/05 08:31:35 vixie Exp $";
 #else
-static char rcsid[] = "$OpenBSD: getnetnamadr.c,v 1.24 2005/03/25 13:24:12 otto Exp $";
+static char rcsid[] = "$OpenBSD: getnetnamadr.c,v 1.25 2005/03/30 02:58:28 tedu Exp $";
 #endif
 #endif /* LIBC_SCCS and not lint */
 
@@ -259,7 +259,7 @@ getnetbyaddr(in_addr_t net, int net_type)
 	char lookups[MAXDNSLUS];
 	int i;
 
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1)
+	if (_res_init(0) == -1)
 		return(_getnetbyaddr(net, net_type));
 
 	bcopy(_resp->lookups, lookups, sizeof lookups);
@@ -347,7 +347,7 @@ getnetbyname(const char *net)
 	char lookups[MAXDNSLUS];
 	int i;
 
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1)
+	if (_res_init(0) == -1)
 		return (_getnetbyname(net));
 
 	bcopy(_resp->lookups, lookups, sizeof lookups);
diff --git a/lib/libc/net/getrrsetbyname.c b/lib/libc/net/getrrsetbyname.c
index dcfc86a6918..e679eb5d963 100644
--- a/lib/libc/net/getrrsetbyname.c
+++ b/lib/libc/net/getrrsetbyname.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: getrrsetbyname.c,v 1.9 2005/03/25 13:24:12 otto Exp $ */
+/* $OpenBSD: getrrsetbyname.c,v 1.10 2005/03/30 02:58:28 tedu Exp $ */
 
 /*
  * Copyright (c) 2001 Jakob Schlyter. All rights reserved.
@@ -126,7 +126,7 @@ getrrsetbyname(const char *hostname, unsigned int rdclass,
 	}
 
 	/* initialize resolver */
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1) {
+	if (_res_init(0) == -1) {
 		result = ERRSET_FAIL;
 		goto fail;
 	}
diff --git a/lib/libc/net/res_debug.c b/lib/libc/net/res_debug.c
index 02f9e4a1ea1..82a067c1f0a 100644
--- a/lib/libc/net/res_debug.c
+++ b/lib/libc/net/res_debug.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: res_debug.c,v 1.19 2005/03/25 13:24:12 otto Exp $	*/
+/*	$OpenBSD: res_debug.c,v 1.20 2005/03/30 02:58:28 tedu Exp $	*/
 
 /*
  * ++Copyright++ 1985, 1990, 1993
@@ -78,7 +78,7 @@
 static char sccsid[] = "@(#)res_debug.c	8.1 (Berkeley) 6/4/93";
 static char rcsid[] = "$From: res_debug.c,v 8.19 1996/11/26 10:11:23 vixie Exp $";
 #else
-static char rcsid[] = "$OpenBSD: res_debug.c,v 1.19 2005/03/25 13:24:12 otto Exp $";
+static char rcsid[] = "$OpenBSD: res_debug.c,v 1.20 2005/03/30 02:58:28 tedu Exp $";
 #endif
 #endif /* LIBC_SCCS and not lint */
 
@@ -264,7 +264,7 @@ __fp_nquery(const u_char *msg, int len, FILE *file)
 	const HEADER *hp;
 	int n;
 
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1)
+	if (_res_init(0) == -1)
 		return;
 
 #define TruncTest(x) if (x > endMark) goto trunc
@@ -462,7 +462,7 @@ __p_rr(const u_char *cp, const u_char *msg, FILE *file)
 	char rrname[MAXDNAME];		/* The fqdn of this RR */
 	char base64_key[MAX_KEY_BASE64];
 
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1) {
+	if (_res_init(0) == -1) {
 		h_errno = NETDB_INTERNAL;
 		return (NULL);
 	}
diff --git a/lib/libc/net/res_init.c b/lib/libc/net/res_init.c
index f4a8d31cb1f..110542a4042 100644
--- a/lib/libc/net/res_init.c
+++ b/lib/libc/net/res_init.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: res_init.c,v 1.31 2005/03/25 13:24:12 otto Exp $	*/
+/*	$OpenBSD: res_init.c,v 1.32 2005/03/30 02:58:28 tedu Exp $	*/
 
 /*
  * ++Copyright++ 1985, 1989, 1993
@@ -60,7 +60,7 @@
 static char sccsid[] = "@(#)res_init.c	8.1 (Berkeley) 6/7/93";
 static char rcsid[] = "$From: res_init.c,v 8.7 1996/09/28 06:51:07 vixie Exp $";
 #else
-static char rcsid[] = "$OpenBSD: res_init.c,v 1.31 2005/03/25 13:24:12 otto Exp $";
+static char rcsid[] = "$OpenBSD: res_init.c,v 1.32 2005/03/30 02:58:28 tedu Exp $";
 #endif
 #endif /* LIBC_SCCS and not lint */
 
@@ -68,6 +68,7 @@ static char rcsid[] = "$OpenBSD: res_init.c,v 1.31 2005/03/25 13:24:12 otto Exp
 #include <sys/param.h>
 #include <sys/socket.h>
 #include <sys/time.h>
+#include <sys/stat.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <arpa/nameser.h>
@@ -131,6 +132,8 @@ void *__THREAD_NAME(_res_ext);
 struct __res_state_ext _res_ext;
 #endif /* INET6 */
 
+int __res_chktime = 30;
+
 /*
  * Set up default settings.  If the configuration file exist, the values
  * there will have precedence.  Otherwise, the server address is set to
@@ -155,6 +158,14 @@ struct __res_state_ext _res_ext;
 int
 res_init(void)
 {
+
+	return (_res_init(1));
+}
+
+int
+_res_init(int usercall)
+{
+	struct stat sb;
 	struct __res_state *_resp = _THREAD_PRIVATE(_res, _res, &_res);
 #ifdef INET6
 	struct __res_state_ext *_res_extp = _THREAD_PRIVATE(_res_ext, _res_ext,
@@ -176,6 +187,29 @@ res_init(void)
 	int dots;
 #endif
 
+	if (usercall == 0) {
+		if (_resp->options & RES_INIT &&
+		    _resp->reschktime >= time(NULL))
+			return (0);
+		_resp->reschktime = time(NULL) + __res_chktime;
+		if (stat(_PATH_RESCONF, &sb) != -1) {
+			if (timespeccmp(&sb.st_mtimespec,
+			    &_resp->restimespec, ==))
+				return (0);
+			else
+				_resp->restimespec = sb.st_mtimespec;
+		} else {
+			/*
+			 * Lost the file, in chroot?
+			 * Don' trash settings
+			 */
+			if (timespecisset(&_resp->restimespec))
+				return (0);
+		}
+	} else
+		_resp->reschktime = time(NULL) + __res_chktime;
+
+
 	/*
 	 * These three fields used to be statically initialized.  This made
 	 * it hard to use this code in a shared library.  It is necessary,
diff --git a/lib/libc/net/res_mkquery.c b/lib/libc/net/res_mkquery.c
index 28ae92056d8..a6c37379f9d 100644
--- a/lib/libc/net/res_mkquery.c
+++ b/lib/libc/net/res_mkquery.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: res_mkquery.c,v 1.15 2005/03/25 13:24:12 otto Exp $	*/
+/*	$OpenBSD: res_mkquery.c,v 1.16 2005/03/30 02:58:28 tedu Exp $	*/
 
 /*
  * ++Copyright++ 1985, 1993
@@ -56,7 +56,7 @@
 static char sccsid[] = "@(#)res_mkquery.c	8.1 (Berkeley) 6/4/93";
 static char rcsid[] = "$From: res_mkquery.c,v 8.5 1996/08/27 08:33:28 vixie Exp $";
 #else
-static char rcsid[] = "$OpenBSD: res_mkquery.c,v 1.15 2005/03/25 13:24:12 otto Exp $";
+static char rcsid[] = "$OpenBSD: res_mkquery.c,v 1.16 2005/03/30 02:58:28 tedu Exp $";
 #endif
 #endif /* LIBC_SCCS and not lint */
 
@@ -94,7 +94,7 @@ res_mkquery(int op,
 	int n;
 	u_char *dnptrs[20], **dpp, **lastdnptr;
 
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1) {
+	if (_res_init(0) == -1) {
 		h_errno = NETDB_INTERNAL;
 		return (-1);
 	}
diff --git a/lib/libc/net/res_query.c b/lib/libc/net/res_query.c
index 677c411a6e4..4af1651cf13 100644
--- a/lib/libc/net/res_query.c
+++ b/lib/libc/net/res_query.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: res_query.c,v 1.22 2005/03/25 13:24:12 otto Exp $	*/
+/*	$OpenBSD: res_query.c,v 1.23 2005/03/30 02:58:28 tedu Exp $	*/
 
 /*
  * ++Copyright++ 1988, 1993
@@ -56,7 +56,7 @@
 static char sccsid[] = "@(#)res_query.c	8.1 (Berkeley) 6/4/93";
 static char rcsid[] = "$From: res_query.c,v 8.9 1996/09/22 00:13:28 vixie Exp $";
 #else
-static char rcsid[] = "$OpenBSD: res_query.c,v 1.22 2005/03/25 13:24:12 otto Exp $";
+static char rcsid[] = "$OpenBSD: res_query.c,v 1.23 2005/03/30 02:58:28 tedu Exp $";
 #endif
 #endif /* LIBC_SCCS and not lint */
 
@@ -111,7 +111,7 @@ res_query(const char *name,
 
 	hp->rcode = NOERROR;	/* default */
 
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1) {
+	if (_res_init(0) == -1) {
 		h_errno = NETDB_INTERNAL;
 		return (-1);
 	}
@@ -193,7 +193,7 @@ res_search(const char *name,
 	int trailing_dot, ret, saved_herrno;
 	int got_nodata = 0, got_servfail = 0, tried_as_is = 0;
 
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1) {
+	if (_res_init(0) == -1) {
 		h_errno = NETDB_INTERNAL;
 		return (-1);
 	}
@@ -332,7 +332,7 @@ res_querydomain(const char *name,
 	const char *longname = nbuf;
 	int n;
 
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1) {
+	if (_res_init(0) == -1) {
 		h_errno = NETDB_INTERNAL;
 		return (-1);
 	}
diff --git a/lib/libc/net/res_send.c b/lib/libc/net/res_send.c
index 04eb268d902..ee7ce430350 100644
--- a/lib/libc/net/res_send.c
+++ b/lib/libc/net/res_send.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: res_send.c,v 1.17 2005/03/25 13:24:12 otto Exp $	*/
+/*	$OpenBSD: res_send.c,v 1.18 2005/03/30 02:58:28 tedu Exp $	*/
 
 /*
  * ++Copyright++ 1985, 1989, 1993
@@ -60,7 +60,7 @@
 static char sccsid[] = "@(#)res_send.c	8.1 (Berkeley) 6/4/93";
 static char rcsid[] = "$From: res_send.c,v 8.12 1996/10/08 04:51:06 vixie Exp $";
 #else
-static char rcsid[] = "$OpenBSD: res_send.c,v 1.17 2005/03/25 13:24:12 otto Exp $";
+static char rcsid[] = "$OpenBSD: res_send.c,v 1.18 2005/03/30 02:58:28 tedu Exp $";
 #endif
 #endif /* LIBC_SCCS and not lint */
 
@@ -343,7 +343,7 @@ res_send(const u_char *buf, int buflen, u_char *ans, int anssiz)
 	int n;
 	u_int badns;	/* XXX NSMAX can't exceed #/bits in this var */
 
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1) {
+	if (_res_init(0) == -1) {
 		/* errno should have been set by res_init() in this case. */
 		return (-1);
 	}
diff --git a/lib/libc/net/sethostent.c b/lib/libc/net/sethostent.c
index 2140d65d08b..c0eae942ca0 100644
--- a/lib/libc/net/sethostent.c
+++ b/lib/libc/net/sethostent.c
@@ -28,7 +28,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char rcsid[] = "$OpenBSD: sethostent.c,v 1.7 2005/03/25 13:24:12 otto Exp $";
+static char rcsid[] = "$OpenBSD: sethostent.c,v 1.8 2005/03/30 02:58:28 tedu Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <sys/param.h>
@@ -44,7 +44,7 @@ sethostent(int stayopen)
 {
 	struct __res_state *_resp = _THREAD_PRIVATE(_res, _res, &_res);
 
-	if ((_resp->options & RES_INIT) == 0 && res_init() == -1)
+	if (_res_init(0) == -1)
 		return;
 	if (stayopen)
 		_resp->options |= RES_STAYOPEN | RES_USEVC;