1 files changed, 328 insertions, 129 deletions

diff --git a/resolv/gethnamaddr.c b/resolv/gethnamaddr.c
index 96248bc0de..35e9007ca7 100644
--- a/resolv/gethnamaddr.c
+++ b/resolv/gethnamaddr.c
@@ -1,8 +1,8 @@
 /*
- * ++Copyright++ 1985, 1988
+ * ++Copyright++ 1985, 1988, 1993
  * -
- * Copyright (c) 1985, 1988 Regents of the University of California.
- * All rights reserved.
+ * Copyright (c) 1985, 1988, 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
@@ -54,7 +54,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char sccsid[] = "@(#)gethostnamadr.c	6.47 (Berkeley) 6/18/92";
+static char sccsid[] = "@(#)gethostnamadr.c	8.1 (Berkeley) 6/4/93";
 static char rcsid[] = "$Id$";
 #endif /* LIBC_SCCS and not lint */
 
@@ -63,27 +63,47 @@ static char rcsid[] = "$Id$";
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <arpa/nameser.h>
+
+#include <stdio.h>
 #include <netdb.h>
 #include <resolv.h>
-#include <stdio.h>
 #include <ctype.h>
 #include <errno.h>
-#include "../conf/portability.h"
+#include <syslog.h>
+
+#ifndef LOG_AUTH
+# define LOG_AUTH 0
+#endif
+
+#define MULTI_PTRS_ARE_ALIASES 1	/* XXX - experimental */
+
+#if defined(BSD) && (BSD >= 199103)
+# include <string.h>
+#else
+# include "../conf/portability.h"
+#endif
+#if defined(USE_OPTIONS_H)
+# include <../conf/options.h>
+#endif
 
 #define	MAXALIASES	35
 #define	MAXADDRS	35
 
+static const char AskedForGot[] =
+			  "gethostby*.getanswer: asked for \"%s\", got \"%s\"";
+
 static char *h_addr_ptrs[MAXADDRS + 1];
 
 static struct hostent host;
 static char *host_aliases[MAXALIASES];
-static char hostbuf[BUFSIZ+1];
+static char hostbuf[8*1024];
 static struct in_addr host_addr;
 static FILE *hostf = NULL;
-static char hostaddr[MAXADDRS];
-static char *host_addrs[2];
 static int stayopen = 0;
-char *strpbrk();
+
+#ifdef RESOLVSORT
+static void addrsort __P((char **, int));
+#endif
 
 #if PACKETSZ > 1024
 #define	MAXPACKET	PACKETSZ
@@ -104,20 +124,23 @@ typedef union {
 extern int h_errno;
 
 static struct hostent *
-getanswer(answer, anslen, iquery)
-	querybuf *answer;
+getanswer(answer, anslen, qname, qclass, qtype)
+	const querybuf *answer;
 	int anslen;
-	int iquery;
+	const char *qname;
+	int qclass, qtype;
 {
-	register HEADER *hp;
-	register u_char *cp;
+	register const HEADER *hp;
+	register const u_char *cp;
 	register int n;
-	u_char *eom;
-	char *bp, **ap;
+	const u_char *eom;
+	char *bp, **ap, **hap;
 	int type, class, buflen, ancount, qdcount;
-	int haveanswer, getclass = C_ANY;
-	char **hap;
+	int haveanswer, had_error;
+	int toobig = 0;
+	char tbuf[MAXDNAME+1];
 
+	host.h_name = NULL;
 	eom = answer->buf + anslen;
 	/*
 	 * find first satisfactory answer
@@ -126,31 +149,28 @@ getanswer(answer, anslen, iquery)
 	ancount = ntohs(hp->ancount);
 	qdcount = ntohs(hp->qdcount);
 	bp = hostbuf;
-	buflen = sizeof(hostbuf);
-	cp = answer->buf + sizeof(HEADER);
-	if (qdcount) {
-		if (iquery) {
-			if ((n = dn_expand((u_char *)answer->buf,
-			    (u_char *)eom, (u_char *)cp, (u_char *)bp,
-			    buflen)) < 0) {
-				h_errno = NO_RECOVERY;
-				return ((struct hostent *) NULL);
-			}
-			cp += n + QFIXEDSZ;
-			host.h_name = bp;
-			n = strlen(bp) + 1;
-			bp += n;
-			buflen -= n;
-		} else
-			cp += __dn_skipname(cp, eom) + QFIXEDSZ;
-		while (--qdcount > 0)
-			cp += __dn_skipname(cp, eom) + QFIXEDSZ;
-	} else if (iquery) {
-		if (hp->aa)
-			h_errno = HOST_NOT_FOUND;
-		else
-			h_errno = TRY_AGAIN;
-		return ((struct hostent *) NULL);
+	buflen = sizeof hostbuf;
+	cp = answer->buf + HFIXEDSZ;
+	if (qdcount != 1) {
+		h_errno = NO_RECOVERY;
+		return (NULL);
+	}
+	if ((n = dn_expand(answer->buf, eom, cp, bp, buflen)) < 0) {
+		h_errno = NO_RECOVERY;
+		return (NULL);
+	}
+	cp += n + QFIXEDSZ;
+	if (qtype == T_A) {
+		/* 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 */
+		host.h_name = bp;
+		bp += n;
+		buflen -= n;
+		/* The qname can be abbreviated, but h_name is now absolute. */
+		qname = host.h_name;
 	}
 	ap = host_aliases;
 	*ap = NULL;
@@ -161,91 +181,174 @@ getanswer(answer, anslen, iquery)
 	host.h_addr_list = h_addr_ptrs;
 #endif
 	haveanswer = 0;
-	while (--ancount >= 0 && cp < eom) {
-		if ((n = dn_expand((u_char *)answer->buf, (u_char *)eom,
-		    (u_char *)cp, (u_char *)bp, buflen)) < 0)
-			break;
-		cp += n;
+	had_error = 0;
+	while (ancount-- > 0 && cp < eom && !had_error) {
+		n = dn_expand(answer->buf, eom, cp, bp, buflen);
+		if (n < 0) {
+			had_error++;
+			continue;
+		}
+		cp += n;			/* name */
 		type = _getshort(cp);
- 		cp += sizeof(u_short);
+ 		cp += INT16SZ;			/* type */
 		class = _getshort(cp);
- 		cp += sizeof(u_short) + sizeof(u_int32_t);
+ 		cp += INT16SZ + INT32SZ;	/* class, TTL */
 		n = _getshort(cp);
-		cp += sizeof(u_short);
-		if (type == T_CNAME) {
+		cp += INT16SZ;			/* len */
+		if (class != qclass) {
+			/* XXX - debug? syslog? */
 			cp += n;
+			continue;		/* XXX - had_error++ ? */
+		}
+		if (qtype == T_A && type == T_CNAME) {
 			if (ap >= &host_aliases[MAXALIASES-1])
 				continue;
+			n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
+			if (n < 0) {
+				had_error++;
+				continue;
+			}
+			cp += n;
+			if (host.h_name && strcasecmp(host.h_name, bp) != 0) {
+				syslog(LOG_NOTICE|LOG_AUTH,
+		"gethostby*.getanswer: asked for \"%s\", got CNAME for \"%s\"",
+				       host.h_name, bp);
+				continue;	/* XXX - had_error++ ? */
+			}
+			/* Store alias. */
 			*ap++ = bp;
-			n = strlen(bp) + 1;
+			n = strlen(bp) + 1;	/* for the \0 */
 			bp += n;
 			buflen -= n;
-			continue;
-		}
-		if (iquery && type == T_PTR) {
-			if ((n = dn_expand((u_char *)answer->buf,
-			    (u_char *)eom, (u_char *)cp, (u_char *)bp,
-			    buflen)) < 0) {
-				cp += n;
+			/* Get canonical name. */
+			n = strlen(tbuf) + 1;	/* for the \0 */
+			if (n > buflen) {
+				had_error++;
 				continue;
 			}
-			cp += n;
+			strcpy(bp, tbuf);
 			host.h_name = bp;
-			return(&host);
+			bp += n;
+			buflen -= n;
+			continue;
 		}
-		if (iquery || type != T_A)  {
-#ifdef DEBUG
-			if (_res.options & RES_DEBUG)
-				printf("unexpected answer type %d, size %d\n",
-					type, n);
-#endif
+		if (type != qtype) {
+			syslog(LOG_NOTICE|LOG_AUTH,
+		     "gethostby*.getanswer: asked for type %d(%s), got %d(%s)",
+			       qtype, qname, type, bp);
 			cp += n;
-			continue;
+			continue;		/* XXX - had_error++ ? */
 		}
-		if (haveanswer) {
-			if (n != host.h_length) {
+		switch (type) {
+		case T_PTR:
+			if (strcasecmp(qname, bp) != 0) {
+				syslog(LOG_NOTICE|LOG_AUTH,
+				       AskedForGot, qname, bp);
 				cp += n;
-				continue;
+				continue;	/* XXX - had_error++ ? */
+			}
+			n = dn_expand(answer->buf, eom, cp, bp, buflen);
+			if (n < 0) {
+				had_error++;
+				break;
+			}
+#if MULTI_PTRS_ARE_ALIASES
+			cp += n;
+			if (!haveanswer)
+				host.h_name = bp;
+			else if (ap < &host_aliases[MAXALIASES-1])
+				*ap++ = bp;
+			else
+				n = -1;
+			if (n != -1) {
+				n = strlen(bp) + 1;	/* for the \0 */
+				bp += n;
+				buflen -= n;
 			}
-			if (class != getclass) {
+			break;
+#else
+			host.h_name = bp;
+			return (&host);
+#endif
+		case T_A:
+			if (strcasecmp(host.h_name, bp) != 0) {
+				syslog(LOG_NOTICE|LOG_AUTH,
+				       AskedForGot, host.h_name, bp);
 				cp += n;
-				continue;
+				continue;	/* XXX - had_error++ ? */
 			}
-		} else {
-			host.h_length = n;
-			getclass = class;
-			host.h_addrtype = (class == C_IN) ? AF_INET : AF_UNSPEC;
-			if (!iquery) {
+			if (haveanswer) {
+				if (n != host.h_length) {
+					cp += n;
+					continue;
+				}
+			} else {
+				register int nn;
+
+				host.h_length = n;
+				host.h_addrtype = (class == C_IN)
+						  ? AF_INET
+						  : AF_UNSPEC;
 				host.h_name = bp;
-				bp += strlen(bp) + 1;
+				nn = strlen(bp) + 1;	/* for the \0 */
+				bp += nn;
+				buflen -= nn;
 			}
-		}
 
-		bp += sizeof(align) - ((u_int32_t)bp % sizeof(align));
+			bp += sizeof(align) - ((u_long)bp % sizeof(align));
 
-		if (bp + n >= &hostbuf[sizeof(hostbuf)]) {
+			if (bp + n >= &hostbuf[sizeof hostbuf]) {
 #ifdef DEBUG
-			if (_res.options & RES_DEBUG)
-				printf("size (%d) too big\n", n);
+				if (_res.options & RES_DEBUG)
+					printf("size (%d) too big\n", n);
 #endif
+				had_error++;
+				continue;
+			}
+			if (hap >= &h_addr_ptrs[MAXADDRS-1]) {
+				if (_res.options & RES_DEBUG && !toobig++)
+					printf("Too many addresses (%d)\n",
+					       MAXADDRS);
+				cp += n;
+				continue;
+			}
+			bcopy(cp, *hap++ = bp, n);
+			bp += n;
+			cp += n;
 			break;
-		}
-		bcopy(cp, *hap++ = bp, n);
-		bp +=n;
-		cp += n;
-		haveanswer++;
-	}
+		default:
+			abort();
+		} /*switch*/
+		if (!had_error)
+			haveanswer++;
+	} /*while*/
 	if (haveanswer) {
 		*ap = NULL;
-#if BSD >= 43 || defined(h_addr)	/* new-style hostent structure */
 		*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 &&
+		    qclass == C_IN && qtype == T_A)
+			addrsort(h_addr_ptrs, haveanswer);
+# endif /*RESOLVSORT*/
+#if BSD >= 43 || defined(h_addr)	/* new-style hostent structure */
+		/* nothing */
 #else
 		host.h_addr = h_addr_ptrs[0];
-#endif
+#endif /*BSD*/
+		if (!host.h_name) {
+			n = strlen(qname) + 1;	/* for the \0 */
+			strcpy(bp, qname);
+			host.h_name = bp;
+		}
 		return (&host);
 	} else {
 		h_errno = TRY_AGAIN;
-		return ((struct hostent *) NULL);
+		return (NULL);
 	}
 }
 
@@ -274,15 +377,15 @@ gethostbyname(name)
 				 */
 				if (!inet_aton(name, &host_addr)) {
 					h_errno = HOST_NOT_FOUND;
-					return((struct hostent *) NULL);
+					return (NULL);
 				}
 				host.h_name = (char *)name;
 				host.h_aliases = host_aliases;
 				host_aliases[0] = NULL;
 				host.h_addrtype = AF_INET;
-				host.h_length = sizeof(u_int32_t);
+				host.h_length = INT32SZ;
 				h_addr_ptrs[0] = (char *)&host_addr;
-				h_addr_ptrs[1] = (char *)0;
+				h_addr_ptrs[1] = NULL;
 #if BSD >= 43 || defined(h_addr)	/* new-style hostent structure */
 				host.h_addr_list = h_addr_ptrs;
 #else
@@ -302,9 +405,9 @@ gethostbyname(name)
 		if (errno == ECONNREFUSED)
 			return (_gethtbyname(name));
 		else
-			return ((struct hostent *) NULL);
+			return (NULL);
 	}
-	return (getanswer(&buf, n, 0));
+	return (getanswer(&buf, n, name, C_IN, T_A));
 }
 
 struct hostent *
@@ -315,17 +418,22 @@ gethostbyaddr(addr, len, type)
 	int n;
 	querybuf buf;
 	register struct hostent *hp;
-	char qbuf[MAXDNAME];
+	char qbuf[MAXDNAME+1];
+#ifdef SUNSECURITY
+	register struct hostent *rhp;
+	char **haddr;
+	u_long old_options;
+#endif /*SUNSECURITY*/
 	extern struct hostent *_gethtbyaddr();
 	
 	if (type != AF_INET)
-		return ((struct hostent *) NULL);
+		return (NULL);
 	(void)sprintf(qbuf, "%u.%u.%u.%u.in-addr.arpa",
 		((unsigned)addr[3] & 0xff),
 		((unsigned)addr[2] & 0xff),
 		((unsigned)addr[1] & 0xff),
 		((unsigned)addr[0] & 0xff));
-	n = res_query(qbuf, C_IN, T_PTR, (char *)&buf, sizeof(buf));
+	n = res_query(qbuf, C_IN, T_PTR, (u_char *)buf.buf, sizeof buf.buf);
 	if (n < 0) {
 #ifdef DEBUG
 		if (_res.options & RES_DEBUG)
@@ -333,31 +441,57 @@ gethostbyaddr(addr, len, type)
 #endif
 		if (errno == ECONNREFUSED)
 			return (_gethtbyaddr(addr, len, type));
-		return ((struct hostent *) NULL);
+		return (NULL);
+	}
+	if (!(hp = getanswer(&buf, n, qbuf, C_IN, T_PTR)))
+		return (NULL);
+#ifdef SUNSECURITY
+	/*
+	 * turn off search as the name should be absolute,
+	 * 'localhost' should be matched by defnames
+	 */
+	old_options = _res.options;
+	_res.options &= ~RES_DNSRCH;
+	_res.options |= RES_DEFNAMES;
+	if (!(rhp = gethostbyname(hp->h_name))) {
+		syslog(LOG_NOTICE|LOG_AUTH,
+		       "gethostbyaddr: No A record for %s (verifying [%s])",
+		       hp->h_name, inet_ntoa(*((struct in_addr *)addr)));
+		_res.options = old_options;
+		return (NULL);
 	}
-	hp = getanswer(&buf, n, 1);
-	if (hp == NULL)
-		return ((struct hostent *) NULL);
+	_res.options = old_options;
+	for (haddr = rhp->h_addr_list; *haddr; haddr++)
+		if (!memcmp(*haddr, addr, INADDRSZ))
+			break;
+	if (!*haddr) {
+		syslog(LOG_NOTICE|LOG_AUTH,
+		       "gethostbyaddr: A record of %s != PTR record [%s]",
+		       hp->h_name, inet_ntoa(*((struct in_addr *)addr)));
+		h_errno = HOST_NOT_FOUND;
+		return (NULL);
+	}
+#endif /*SUNSECURITY*/
 	hp->h_addrtype = type;
 	hp->h_length = len;
 	h_addr_ptrs[0] = (char *)&host_addr;
-	h_addr_ptrs[1] = (char *)0;
+	h_addr_ptrs[1] = NULL;
 	host_addr = *(struct in_addr *)addr;
 #if BSD < 43 && !defined(h_addr)	/* new-style hostent structure */
 	hp->h_addr = h_addr_ptrs[0];
 #endif
-	return(hp);
+	return (hp);
 }
 
 void
 _sethtent(f)
 	int f;
 {
-	if (hostf == NULL)
+	if (!hostf)
 		hostf = fopen(_PATH_HOSTS, "r" );
 	else
 		rewind(hostf);
-	stayopen |= f;
+	stayopen = f;
 }
 
 void
@@ -375,35 +509,36 @@ _gethtent()
 	char *p;
 	register char *cp, **q;
 
-	if (hostf == NULL && (hostf = fopen(_PATH_HOSTS, "r" )) == NULL)
+	if (!hostf && !(hostf = fopen(_PATH_HOSTS, "r" )))
 		return (NULL);
 again:
-	if ((p = fgets(hostbuf, BUFSIZ, hostf)) == NULL)
+	if (!(p = fgets(hostbuf, sizeof hostbuf, hostf)))
 		return (NULL);
 	if (*p == '#')
 		goto again;
-	cp = strpbrk(p, "#\n");
-	if (cp == NULL)
+	if (!(cp = strpbrk(p, "#\n")))
 		goto again;
 	*cp = '\0';
-	cp = strpbrk(p, " \t");
-	if (cp == NULL)
+	if (!(cp = strpbrk(p, " \t")))
 		goto again;
 	*cp++ = '\0';
 	/* THIS STUFF IS INTERNET SPECIFIC */
+	if (!inet_aton(p, &host_addr))
+		goto again;
+	h_addr_ptrs[0] = (char *)&host_addr;
+	h_addr_ptrs[1] = NULL;
 #if BSD >= 43 || defined(h_addr)	/* new-style hostent structure */
-	host.h_addr_list = host_addrs;
+	host.h_addr_list = h_addr_ptrs;
+#else
+	host.h_addr = h_addr_ptrs[0];
 #endif
-	host.h_addr = hostaddr;
-	*((u_int32_t *)host.h_addr) = inet_addr(p);
-	host.h_length = sizeof (u_int32_t);
+	host.h_length = INT32SZ;
 	host.h_addrtype = AF_INET;
 	while (*cp == ' ' || *cp == '\t')
 		cp++;
 	host.h_name = cp;
 	q = host.h_aliases = host_aliases;
-	cp = strpbrk(cp, " \t");
-	if (cp != NULL) 
+	if (cp = strpbrk(cp, " \t"))
 		*cp++ = '\0';
 	while (cp && *cp) {
 		if (*cp == ' ' || *cp == '\t') {
@@ -412,8 +547,7 @@ again:
 		}
 		if (q < &host_aliases[MAXALIASES - 1])
 			*q++ = cp;
-		cp = strpbrk(cp, " \t");
-		if (cp != NULL)
+		if (cp = strpbrk(cp, " \t"))
 			*cp++ = '\0';
 	}
 	*q = NULL;
@@ -455,6 +589,51 @@ _gethtbyaddr(addr, len, type)
 	return (p);
 }
 
+#ifdef RESOLVSORT
+static void
+addrsort(ap, num)
+	char **ap;
+	int num;
+{
+	int i, j;
+	char **p;
+	short aval[MAXADDRS];
+	int needsort = 0;
+
+	p = ap;
+	for (i = 0; i < num; i++, p++) {
+	    for (j = 0 ; j < _res.nsort; j++)
+		if (_res.sort_list[j].addr.s_addr == 
+		    (((struct in_addr *)(*p))->s_addr & _res.sort_list[j].mask))
+			break;
+	    aval[i] = j;
+	    if (needsort == 0 && i > 0 && j < aval[i-1])
+		needsort = i;
+	}
+	if (!needsort)
+	    return;
+
+	while (needsort < num) {
+	    for (j = needsort - 1; j >= 0; j--) {
+		if (aval[j] > aval[j+1]) {
+		    char *hp;
+
+		    i = aval[j];
+		    aval[j] = aval[j+1];
+		    aval[j+1] = i;
+
+		    hp = ap[j];
+		    ap[j] = ap[j+1];
+		    ap[j+1] = hp;
+
+		} else
+		    break;
+	    }
+	    needsort++;
+	}
+}
+#endif
+
 #if defined(BSD43_BSD43_NFS) || defined(sun)
 /* some libc's out there are bound internally to these names (UMIPS) */
 void
@@ -474,7 +653,7 @@ struct hostent *
 ht_gethostbyname(name)
 	char *name;
 {
-	return _gethtbyname(name);
+	return (_gethtbyname(name));
 }
 
 struct hostent *
@@ -482,13 +661,13 @@ ht_gethostbyaddr(addr, len, type)
 	const char *addr;
 	int len, type;
 {
-	return _gethtbyaddr(addr, len, type);
+	return (_gethtbyaddr(addr, len, type));
 }
 
 struct hostent *
 gethostent()
 {
-	return _gethtent();
+	return (_gethtent());
 }
 
 void
@@ -501,6 +680,26 @@ dns_service()
 dn_skipname(comp_dn, eom)
 	const u_char *comp_dn, *eom;
 {
-	return __dn_skipname(comp_dn, eom);
+	return (__dn_skipname(comp_dn, eom));
 }
 #endif /*old-style libc with yp junk in it*/
+
+#ifdef ultrix
+/* more icky libc packaging in ultrix */
+int
+local_hostname_length(hostname)
+	const char *hostname;
+{
+	int len_host, len_domain;
+
+	if (!*_res.defdname)
+		res_init();
+	len_host = strlen(hostname);
+	len_domain = strlen(_res.defdname);
+	if (len_host > len_domain &&
+	    !strcasecmp(hostname + len_host - len_domain, _res.defdname) &&
+	    hostname[len_host - len_domain - 1] == '.')
+		return (len_host - len_domain - 1);
+	return (0);
+}
+#endif