xref: /titanic_52/usr/src/lib/libresolv2/common/irs/hesiod.c (revision 9525b14bcdeb5b5f6f95ab27c2f48f18bd2ec829)
17c478bd9Sstevel@tonic-gate #if defined(LIBC_SCCS) && !defined(lint)
2*9525b14bSRao Shoaib static const char rcsid[] = "$Id: hesiod.c,v 1.7 2005/07/28 06:51:48 marka Exp $";
37c478bd9Sstevel@tonic-gate #endif
47c478bd9Sstevel@tonic-gate 
57c478bd9Sstevel@tonic-gate /*
6*9525b14bSRao Shoaib  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
77c478bd9Sstevel@tonic-gate  * Copyright (c) 1996,1999 by Internet Software Consortium.
87c478bd9Sstevel@tonic-gate  *
97c478bd9Sstevel@tonic-gate  * Permission to use, copy, modify, and distribute this software for any
107c478bd9Sstevel@tonic-gate  * purpose with or without fee is hereby granted, provided that the above
117c478bd9Sstevel@tonic-gate  * copyright notice and this permission notice appear in all copies.
127c478bd9Sstevel@tonic-gate  *
13*9525b14bSRao Shoaib  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
14*9525b14bSRao Shoaib  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
15*9525b14bSRao Shoaib  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
16*9525b14bSRao Shoaib  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
17*9525b14bSRao Shoaib  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
18*9525b14bSRao Shoaib  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
19*9525b14bSRao Shoaib  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
207c478bd9Sstevel@tonic-gate  */
217c478bd9Sstevel@tonic-gate 
227c478bd9Sstevel@tonic-gate 
23*9525b14bSRao Shoaib /*! \file
24*9525b14bSRao Shoaib  * \brief
257c478bd9Sstevel@tonic-gate  * hesiod.c --- the core portion of the hesiod resolver.
267c478bd9Sstevel@tonic-gate  *
277c478bd9Sstevel@tonic-gate  * This file is derived from the hesiod library from Project Athena;
287c478bd9Sstevel@tonic-gate  * It has been extensively rewritten by Theodore Ts'o to have a more
297c478bd9Sstevel@tonic-gate  * thread-safe interface.
30*9525b14bSRao Shoaib  * \author
31*9525b14bSRao Shoaib  * This file is primarily maintained by <tytso@mit.edu> and <ghudson@mit.edu>.
327c478bd9Sstevel@tonic-gate  */
337c478bd9Sstevel@tonic-gate 
347c478bd9Sstevel@tonic-gate /* Imports */
357c478bd9Sstevel@tonic-gate 
367c478bd9Sstevel@tonic-gate #include "port_before.h"
377c478bd9Sstevel@tonic-gate 
387c478bd9Sstevel@tonic-gate #include <sys/types.h>
397c478bd9Sstevel@tonic-gate #include <netinet/in.h>
407c478bd9Sstevel@tonic-gate #include <arpa/nameser.h>
417c478bd9Sstevel@tonic-gate 
427c478bd9Sstevel@tonic-gate #include <errno.h>
437c478bd9Sstevel@tonic-gate #include <netdb.h>
447c478bd9Sstevel@tonic-gate #include <resolv.h>
457c478bd9Sstevel@tonic-gate #include <stdio.h>
467c478bd9Sstevel@tonic-gate #include <stdlib.h>
477c478bd9Sstevel@tonic-gate #include <string.h>
487c478bd9Sstevel@tonic-gate 
497c478bd9Sstevel@tonic-gate #include "port_after.h"
507c478bd9Sstevel@tonic-gate 
517c478bd9Sstevel@tonic-gate #include "pathnames.h"
527c478bd9Sstevel@tonic-gate #include "hesiod.h"
537c478bd9Sstevel@tonic-gate #include "hesiod_p.h"
547c478bd9Sstevel@tonic-gate 
557c478bd9Sstevel@tonic-gate /* Forward */
567c478bd9Sstevel@tonic-gate 
577c478bd9Sstevel@tonic-gate int		hesiod_init(void **context);
587c478bd9Sstevel@tonic-gate void		hesiod_end(void *context);
597c478bd9Sstevel@tonic-gate char *		hesiod_to_bind(void *context, const char *name,
607c478bd9Sstevel@tonic-gate 			       const char *type);
617c478bd9Sstevel@tonic-gate char **		hesiod_resolve(void *context, const char *name,
627c478bd9Sstevel@tonic-gate 			       const char *type);
637c478bd9Sstevel@tonic-gate void		hesiod_free_list(void *context, char **list);
647c478bd9Sstevel@tonic-gate 
657c478bd9Sstevel@tonic-gate static int	parse_config_file(struct hesiod_p *ctx, const char *filename);
667c478bd9Sstevel@tonic-gate static char **	get_txt_records(struct hesiod_p *ctx, int class,
677c478bd9Sstevel@tonic-gate 				const char *name);
687c478bd9Sstevel@tonic-gate static int	init(struct hesiod_p *ctx);
697c478bd9Sstevel@tonic-gate 
707c478bd9Sstevel@tonic-gate /* Public */
717c478bd9Sstevel@tonic-gate 
72*9525b14bSRao Shoaib /*%
737c478bd9Sstevel@tonic-gate  * This function is called to initialize a hesiod_p.
747c478bd9Sstevel@tonic-gate  */
757c478bd9Sstevel@tonic-gate int
767c478bd9Sstevel@tonic-gate hesiod_init(void **context) {
777c478bd9Sstevel@tonic-gate 	struct hesiod_p *ctx;
787c478bd9Sstevel@tonic-gate 	char *cp;
797c478bd9Sstevel@tonic-gate 
807c478bd9Sstevel@tonic-gate 	ctx = malloc(sizeof(struct hesiod_p));
817c478bd9Sstevel@tonic-gate 	if (ctx == 0) {
827c478bd9Sstevel@tonic-gate 		errno = ENOMEM;
837c478bd9Sstevel@tonic-gate 		return (-1);
847c478bd9Sstevel@tonic-gate 	}
857c478bd9Sstevel@tonic-gate 
867c478bd9Sstevel@tonic-gate 	memset(ctx, 0, sizeof (*ctx));
877c478bd9Sstevel@tonic-gate 
887c478bd9Sstevel@tonic-gate 	if (parse_config_file(ctx, _PATH_HESIOD_CONF) < 0) {
897c478bd9Sstevel@tonic-gate #ifdef DEF_RHS
907c478bd9Sstevel@tonic-gate 		/*
917c478bd9Sstevel@tonic-gate 		 * Use compiled in defaults.
927c478bd9Sstevel@tonic-gate 		 */
937c478bd9Sstevel@tonic-gate 		ctx->LHS = malloc(strlen(DEF_LHS) + 1);
947c478bd9Sstevel@tonic-gate 		ctx->RHS = malloc(strlen(DEF_RHS) + 1);
95*9525b14bSRao Shoaib 		if (ctx->LHS == NULL || ctx->RHS == NULL) {
967c478bd9Sstevel@tonic-gate 			errno = ENOMEM;
977c478bd9Sstevel@tonic-gate 			goto cleanup;
987c478bd9Sstevel@tonic-gate 		}
99*9525b14bSRao Shoaib 		strcpy(ctx->LHS, DEF_LHS);	/* (checked) */
100*9525b14bSRao Shoaib 		strcpy(ctx->RHS, DEF_RHS);	/* (checked) */
1017c478bd9Sstevel@tonic-gate #else
1027c478bd9Sstevel@tonic-gate 		goto cleanup;
1037c478bd9Sstevel@tonic-gate #endif
1047c478bd9Sstevel@tonic-gate 	}
1057c478bd9Sstevel@tonic-gate 	/*
1067c478bd9Sstevel@tonic-gate 	 * The default RHS can be overridden by an environment
1077c478bd9Sstevel@tonic-gate 	 * variable.
1087c478bd9Sstevel@tonic-gate 	 */
1097c478bd9Sstevel@tonic-gate 	if ((cp = getenv("HES_DOMAIN")) != NULL) {
1107c478bd9Sstevel@tonic-gate 		size_t RHSlen = strlen(cp) + 2;
1117c478bd9Sstevel@tonic-gate 		if (ctx->RHS)
1127c478bd9Sstevel@tonic-gate 			free(ctx->RHS);
1137c478bd9Sstevel@tonic-gate 		ctx->RHS = malloc(RHSlen);
1147c478bd9Sstevel@tonic-gate 		if (!ctx->RHS) {
1157c478bd9Sstevel@tonic-gate 			errno = ENOMEM;
1167c478bd9Sstevel@tonic-gate 			goto cleanup;
1177c478bd9Sstevel@tonic-gate 		}
1187c478bd9Sstevel@tonic-gate 		if (cp[0] == '.') {
119*9525b14bSRao Shoaib 			strcpy(ctx->RHS, cp);	/* (checked) */
1207c478bd9Sstevel@tonic-gate 		} else {
121*9525b14bSRao Shoaib 			strcpy(ctx->RHS, ".");	/* (checked) */
122*9525b14bSRao Shoaib 			strcat(ctx->RHS, cp);	/* (checked) */
1237c478bd9Sstevel@tonic-gate 		}
1247c478bd9Sstevel@tonic-gate 	}
1257c478bd9Sstevel@tonic-gate 
1267c478bd9Sstevel@tonic-gate 	/*
1277c478bd9Sstevel@tonic-gate 	 * If there is no default hesiod realm set, we return an
1287c478bd9Sstevel@tonic-gate 	 * error.
1297c478bd9Sstevel@tonic-gate 	 */
1307c478bd9Sstevel@tonic-gate 	if (!ctx->RHS) {
1317c478bd9Sstevel@tonic-gate 		errno = ENOEXEC;
1327c478bd9Sstevel@tonic-gate 		goto cleanup;
1337c478bd9Sstevel@tonic-gate 	}
1347c478bd9Sstevel@tonic-gate 
1357c478bd9Sstevel@tonic-gate #if 0
1367c478bd9Sstevel@tonic-gate 	if (res_ninit(ctx->res) < 0)
1377c478bd9Sstevel@tonic-gate 		goto cleanup;
1387c478bd9Sstevel@tonic-gate #endif
1397c478bd9Sstevel@tonic-gate 
1407c478bd9Sstevel@tonic-gate 	*context = ctx;
1417c478bd9Sstevel@tonic-gate 	return (0);
1427c478bd9Sstevel@tonic-gate 
1437c478bd9Sstevel@tonic-gate  cleanup:
1447c478bd9Sstevel@tonic-gate 	hesiod_end(ctx);
1457c478bd9Sstevel@tonic-gate 	return (-1);
1467c478bd9Sstevel@tonic-gate }
1477c478bd9Sstevel@tonic-gate 
148*9525b14bSRao Shoaib /*%
1497c478bd9Sstevel@tonic-gate  * This function deallocates the hesiod_p
1507c478bd9Sstevel@tonic-gate  */
1517c478bd9Sstevel@tonic-gate void
1527c478bd9Sstevel@tonic-gate hesiod_end(void *context) {
1537c478bd9Sstevel@tonic-gate 	struct hesiod_p *ctx = (struct hesiod_p *) context;
1547c478bd9Sstevel@tonic-gate 	int save_errno = errno;
1557c478bd9Sstevel@tonic-gate 
1567c478bd9Sstevel@tonic-gate 	if (ctx->res)
1577c478bd9Sstevel@tonic-gate 		res_nclose(ctx->res);
1587c478bd9Sstevel@tonic-gate 	if (ctx->RHS)
1597c478bd9Sstevel@tonic-gate 		free(ctx->RHS);
1607c478bd9Sstevel@tonic-gate 	if (ctx->LHS)
1617c478bd9Sstevel@tonic-gate 		free(ctx->LHS);
1627c478bd9Sstevel@tonic-gate 	if (ctx->res && ctx->free_res)
1637c478bd9Sstevel@tonic-gate 		(*ctx->free_res)(ctx->res);
1647c478bd9Sstevel@tonic-gate 	free(ctx);
1657c478bd9Sstevel@tonic-gate 	errno = save_errno;
1667c478bd9Sstevel@tonic-gate }
1677c478bd9Sstevel@tonic-gate 
168*9525b14bSRao Shoaib /*%
1697c478bd9Sstevel@tonic-gate  * This function takes a hesiod (name, type) and returns a DNS
1707c478bd9Sstevel@tonic-gate  * name which is to be resolved.
1717c478bd9Sstevel@tonic-gate  */
1727c478bd9Sstevel@tonic-gate char *
1737c478bd9Sstevel@tonic-gate hesiod_to_bind(void *context, const char *name, const char *type) {
1747c478bd9Sstevel@tonic-gate 	struct hesiod_p *ctx = (struct hesiod_p *) context;
1757c478bd9Sstevel@tonic-gate 	char *bindname;
1767c478bd9Sstevel@tonic-gate 	char **rhs_list = NULL;
1777c478bd9Sstevel@tonic-gate 	const char *RHS, *cp;
1787c478bd9Sstevel@tonic-gate 
1797c478bd9Sstevel@tonic-gate 	/* Decide what our RHS is, and set cp to the end of the actual name. */
1807c478bd9Sstevel@tonic-gate 	if ((cp = strchr(name, '@')) != NULL) {
1817c478bd9Sstevel@tonic-gate 		if (strchr(cp + 1, '.'))
1827c478bd9Sstevel@tonic-gate 			RHS = cp + 1;
1837c478bd9Sstevel@tonic-gate 		else if ((rhs_list = hesiod_resolve(context, cp + 1,
1847c478bd9Sstevel@tonic-gate 		    "rhs-extension")) != NULL)
1857c478bd9Sstevel@tonic-gate 			RHS = *rhs_list;
1867c478bd9Sstevel@tonic-gate 		else {
1877c478bd9Sstevel@tonic-gate 			errno = ENOENT;
1887c478bd9Sstevel@tonic-gate 			return (NULL);
1897c478bd9Sstevel@tonic-gate 		}
1907c478bd9Sstevel@tonic-gate 	} else {
1917c478bd9Sstevel@tonic-gate 		RHS = ctx->RHS;
1927c478bd9Sstevel@tonic-gate 		cp = name + strlen(name);
1937c478bd9Sstevel@tonic-gate 	}
1947c478bd9Sstevel@tonic-gate 
1957c478bd9Sstevel@tonic-gate 	/*
1967c478bd9Sstevel@tonic-gate 	 * Allocate the space we need, including up to three periods and
1977c478bd9Sstevel@tonic-gate 	 * the terminating NUL.
1987c478bd9Sstevel@tonic-gate 	 */
1997c478bd9Sstevel@tonic-gate 	if ((bindname = malloc((cp - name) + strlen(type) + strlen(RHS) +
2007c478bd9Sstevel@tonic-gate 	    (ctx->LHS ? strlen(ctx->LHS) : 0) + 4)) == NULL) {
2017c478bd9Sstevel@tonic-gate 		errno = ENOMEM;
2027c478bd9Sstevel@tonic-gate 		if (rhs_list)
2037c478bd9Sstevel@tonic-gate 			hesiod_free_list(context, rhs_list);
2047c478bd9Sstevel@tonic-gate 		return NULL;
2057c478bd9Sstevel@tonic-gate 	}
2067c478bd9Sstevel@tonic-gate 
2077c478bd9Sstevel@tonic-gate 	/* Now put together the DNS name. */
2087c478bd9Sstevel@tonic-gate 	memcpy(bindname, name, cp - name);
2097c478bd9Sstevel@tonic-gate 	bindname[cp - name] = '\0';
2107c478bd9Sstevel@tonic-gate 	strcat(bindname, ".");
2117c478bd9Sstevel@tonic-gate 	strcat(bindname, type);
2127c478bd9Sstevel@tonic-gate 	if (ctx->LHS) {
2137c478bd9Sstevel@tonic-gate 		if (ctx->LHS[0] != '.')
2147c478bd9Sstevel@tonic-gate 			strcat(bindname, ".");
2157c478bd9Sstevel@tonic-gate 		strcat(bindname, ctx->LHS);
2167c478bd9Sstevel@tonic-gate 	}
2177c478bd9Sstevel@tonic-gate 	if (RHS[0] != '.')
2187c478bd9Sstevel@tonic-gate 		strcat(bindname, ".");
2197c478bd9Sstevel@tonic-gate 	strcat(bindname, RHS);
2207c478bd9Sstevel@tonic-gate 
2217c478bd9Sstevel@tonic-gate 	if (rhs_list)
2227c478bd9Sstevel@tonic-gate 		hesiod_free_list(context, rhs_list);
2237c478bd9Sstevel@tonic-gate 
2247c478bd9Sstevel@tonic-gate 	return (bindname);
2257c478bd9Sstevel@tonic-gate }
2267c478bd9Sstevel@tonic-gate 
227*9525b14bSRao Shoaib /*%
2287c478bd9Sstevel@tonic-gate  * This is the core function.  Given a hesiod (name, type), it
2297c478bd9Sstevel@tonic-gate  * returns an array of strings returned by the resolver.
2307c478bd9Sstevel@tonic-gate  */
2317c478bd9Sstevel@tonic-gate char **
2327c478bd9Sstevel@tonic-gate hesiod_resolve(void *context, const char *name, const char *type) {
2337c478bd9Sstevel@tonic-gate 	struct hesiod_p *ctx = (struct hesiod_p *) context;
2347c478bd9Sstevel@tonic-gate 	char *bindname = hesiod_to_bind(context, name, type);
2357c478bd9Sstevel@tonic-gate 	char **retvec;
2367c478bd9Sstevel@tonic-gate 
2377c478bd9Sstevel@tonic-gate 	if (bindname == NULL)
2387c478bd9Sstevel@tonic-gate 		return (NULL);
2397c478bd9Sstevel@tonic-gate 	if (init(ctx) == -1) {
2407c478bd9Sstevel@tonic-gate 		free(bindname);
2417c478bd9Sstevel@tonic-gate 		return (NULL);
2427c478bd9Sstevel@tonic-gate 	}
2437c478bd9Sstevel@tonic-gate 
2447c478bd9Sstevel@tonic-gate 	if ((retvec = get_txt_records(ctx, C_IN, bindname))) {
2457c478bd9Sstevel@tonic-gate 		free(bindname);
2467c478bd9Sstevel@tonic-gate 		return (retvec);
2477c478bd9Sstevel@tonic-gate 	}
2487c478bd9Sstevel@tonic-gate 
2497c478bd9Sstevel@tonic-gate 	if (errno != ENOENT)
2507c478bd9Sstevel@tonic-gate 		return (NULL);
2517c478bd9Sstevel@tonic-gate 
2527c478bd9Sstevel@tonic-gate 	retvec = get_txt_records(ctx, C_HS, bindname);
2537c478bd9Sstevel@tonic-gate 	free(bindname);
2547c478bd9Sstevel@tonic-gate 	return (retvec);
2557c478bd9Sstevel@tonic-gate }
2567c478bd9Sstevel@tonic-gate 
2577c478bd9Sstevel@tonic-gate void
2587c478bd9Sstevel@tonic-gate hesiod_free_list(void *context, char **list) {
2597c478bd9Sstevel@tonic-gate 	char **p;
2607c478bd9Sstevel@tonic-gate 
2617c478bd9Sstevel@tonic-gate 	UNUSED(context);
2627c478bd9Sstevel@tonic-gate 
2637c478bd9Sstevel@tonic-gate 	for (p = list; *p; p++)
2647c478bd9Sstevel@tonic-gate 		free(*p);
2657c478bd9Sstevel@tonic-gate 	free(list);
2667c478bd9Sstevel@tonic-gate }
2677c478bd9Sstevel@tonic-gate 
268*9525b14bSRao Shoaib /*%
2697c478bd9Sstevel@tonic-gate  * This function parses the /etc/hesiod.conf file
2707c478bd9Sstevel@tonic-gate  */
2717c478bd9Sstevel@tonic-gate static int
2727c478bd9Sstevel@tonic-gate parse_config_file(struct hesiod_p *ctx, const char *filename) {
2737c478bd9Sstevel@tonic-gate 	char *key, *data, *cp, **cpp;
2747c478bd9Sstevel@tonic-gate 	char buf[MAXDNAME+7];
2757c478bd9Sstevel@tonic-gate 	FILE *fp;
2767c478bd9Sstevel@tonic-gate 
2777c478bd9Sstevel@tonic-gate 	/*
2787c478bd9Sstevel@tonic-gate 	 * Clear the existing configuration variable, just in case
2797c478bd9Sstevel@tonic-gate 	 * they're set.
2807c478bd9Sstevel@tonic-gate 	 */
2817c478bd9Sstevel@tonic-gate 	if (ctx->RHS)
2827c478bd9Sstevel@tonic-gate 		free(ctx->RHS);
2837c478bd9Sstevel@tonic-gate 	if (ctx->LHS)
2847c478bd9Sstevel@tonic-gate 		free(ctx->LHS);
2857c478bd9Sstevel@tonic-gate 	ctx->RHS = ctx->LHS = 0;
2867c478bd9Sstevel@tonic-gate 
2877c478bd9Sstevel@tonic-gate 	/*
2887c478bd9Sstevel@tonic-gate 	 * Now open and parse the file...
2897c478bd9Sstevel@tonic-gate 	 */
2907c478bd9Sstevel@tonic-gate 	if (!(fp = fopen(filename, "r")))
2917c478bd9Sstevel@tonic-gate 		return (-1);
2927c478bd9Sstevel@tonic-gate 
2937c478bd9Sstevel@tonic-gate 	while (fgets(buf, sizeof(buf), fp) != NULL) {
2947c478bd9Sstevel@tonic-gate 		cp = buf;
2957c478bd9Sstevel@tonic-gate 		if (*cp == '#' || *cp == '\n' || *cp == '\r')
2967c478bd9Sstevel@tonic-gate 			continue;
2977c478bd9Sstevel@tonic-gate 		while(*cp == ' ' || *cp == '\t')
2987c478bd9Sstevel@tonic-gate 			cp++;
2997c478bd9Sstevel@tonic-gate 		key = cp;
3007c478bd9Sstevel@tonic-gate 		while(*cp != ' ' && *cp != '\t' && *cp != '=')
3017c478bd9Sstevel@tonic-gate 			cp++;
3027c478bd9Sstevel@tonic-gate 		*cp++ = '\0';
3037c478bd9Sstevel@tonic-gate 
3047c478bd9Sstevel@tonic-gate 		while(*cp == ' ' || *cp == '\t' || *cp == '=')
3057c478bd9Sstevel@tonic-gate 			cp++;
3067c478bd9Sstevel@tonic-gate 		data = cp;
3077c478bd9Sstevel@tonic-gate 		while(*cp != ' ' && *cp != '\n' && *cp != '\r')
3087c478bd9Sstevel@tonic-gate 			cp++;
3097c478bd9Sstevel@tonic-gate 		*cp++ = '\0';
3107c478bd9Sstevel@tonic-gate 
3117c478bd9Sstevel@tonic-gate 		if (strcmp(key, "lhs") == 0)
3127c478bd9Sstevel@tonic-gate 			cpp = &ctx->LHS;
3137c478bd9Sstevel@tonic-gate 		else if (strcmp(key, "rhs") == 0)
3147c478bd9Sstevel@tonic-gate 			cpp = &ctx->RHS;
3157c478bd9Sstevel@tonic-gate 		else
3167c478bd9Sstevel@tonic-gate 			continue;
3177c478bd9Sstevel@tonic-gate 
3187c478bd9Sstevel@tonic-gate 		*cpp = malloc(strlen(data) + 1);
3197c478bd9Sstevel@tonic-gate 		if (!*cpp) {
3207c478bd9Sstevel@tonic-gate 			errno = ENOMEM;
3217c478bd9Sstevel@tonic-gate 			goto cleanup;
3227c478bd9Sstevel@tonic-gate 		}
3237c478bd9Sstevel@tonic-gate 		strcpy(*cpp, data);
3247c478bd9Sstevel@tonic-gate 	}
3257c478bd9Sstevel@tonic-gate 	fclose(fp);
3267c478bd9Sstevel@tonic-gate 	return (0);
3277c478bd9Sstevel@tonic-gate 
3287c478bd9Sstevel@tonic-gate  cleanup:
3297c478bd9Sstevel@tonic-gate 	fclose(fp);
3307c478bd9Sstevel@tonic-gate 	if (ctx->RHS)
3317c478bd9Sstevel@tonic-gate 		free(ctx->RHS);
3327c478bd9Sstevel@tonic-gate 	if (ctx->LHS)
3337c478bd9Sstevel@tonic-gate 		free(ctx->LHS);
3347c478bd9Sstevel@tonic-gate 	ctx->RHS = ctx->LHS = 0;
3357c478bd9Sstevel@tonic-gate 	return (-1);
3367c478bd9Sstevel@tonic-gate }
3377c478bd9Sstevel@tonic-gate 
338*9525b14bSRao Shoaib /*%
3397c478bd9Sstevel@tonic-gate  * Given a DNS class and a DNS name, do a lookup for TXT records, and
3407c478bd9Sstevel@tonic-gate  * return a list of them.
3417c478bd9Sstevel@tonic-gate  */
3427c478bd9Sstevel@tonic-gate static char **
3437c478bd9Sstevel@tonic-gate get_txt_records(struct hesiod_p *ctx, int class, const char *name) {
3447c478bd9Sstevel@tonic-gate 	struct {
345*9525b14bSRao Shoaib 		int type;		/*%< RR type */
346*9525b14bSRao Shoaib 		int class;		/*%< RR class */
347*9525b14bSRao Shoaib 		int dlen;		/*%< len of data section */
348*9525b14bSRao Shoaib 		u_char *data;		/*%< pointer to data */
3497c478bd9Sstevel@tonic-gate 	} rr;
3507c478bd9Sstevel@tonic-gate 	HEADER *hp;
3517c478bd9Sstevel@tonic-gate 	u_char qbuf[MAX_HESRESP], abuf[MAX_HESRESP];
3527c478bd9Sstevel@tonic-gate 	u_char *cp, *erdata, *eom;
3537c478bd9Sstevel@tonic-gate 	char *dst, *edst, **list;
3547c478bd9Sstevel@tonic-gate 	int ancount, qdcount;
3557c478bd9Sstevel@tonic-gate 	int i, j, n, skip;
3567c478bd9Sstevel@tonic-gate 
3577c478bd9Sstevel@tonic-gate 	/*
3587c478bd9Sstevel@tonic-gate 	 * Construct the query and send it.
3597c478bd9Sstevel@tonic-gate 	 */
3607c478bd9Sstevel@tonic-gate 	n = res_nmkquery(ctx->res, QUERY, name, class, T_TXT, NULL, 0,
3617c478bd9Sstevel@tonic-gate 			 NULL, qbuf, MAX_HESRESP);
3627c478bd9Sstevel@tonic-gate 	if (n < 0) {
3637c478bd9Sstevel@tonic-gate 		errno = EMSGSIZE;
3647c478bd9Sstevel@tonic-gate 		return (NULL);
3657c478bd9Sstevel@tonic-gate 	}
3667c478bd9Sstevel@tonic-gate 	n = res_nsend(ctx->res, qbuf, n, abuf, MAX_HESRESP);
3677c478bd9Sstevel@tonic-gate 	if (n < 0) {
3687c478bd9Sstevel@tonic-gate 		errno = ECONNREFUSED;
3697c478bd9Sstevel@tonic-gate 		return (NULL);
3707c478bd9Sstevel@tonic-gate 	}
3717c478bd9Sstevel@tonic-gate 	if (n < HFIXEDSZ) {
3727c478bd9Sstevel@tonic-gate 		errno = EMSGSIZE;
3737c478bd9Sstevel@tonic-gate 		return (NULL);
3747c478bd9Sstevel@tonic-gate 	}
3757c478bd9Sstevel@tonic-gate 
3767c478bd9Sstevel@tonic-gate 	/*
3777c478bd9Sstevel@tonic-gate 	 * OK, parse the result.
3787c478bd9Sstevel@tonic-gate 	 */
3797c478bd9Sstevel@tonic-gate 	hp = (HEADER *) abuf;
3807c478bd9Sstevel@tonic-gate 	ancount = ntohs(hp->ancount);
3817c478bd9Sstevel@tonic-gate 	qdcount = ntohs(hp->qdcount);
3827c478bd9Sstevel@tonic-gate 	cp = abuf + sizeof(HEADER);
3837c478bd9Sstevel@tonic-gate 	eom = abuf + n;
3847c478bd9Sstevel@tonic-gate 
3857c478bd9Sstevel@tonic-gate 	/* Skip query, trying to get to the answer section which follows. */
3867c478bd9Sstevel@tonic-gate 	for (i = 0; i < qdcount; i++) {
3877c478bd9Sstevel@tonic-gate 		skip = dn_skipname(cp, eom);
3887c478bd9Sstevel@tonic-gate 		if (skip < 0 || cp + skip + QFIXEDSZ > eom) {
3897c478bd9Sstevel@tonic-gate 			errno = EMSGSIZE;
3907c478bd9Sstevel@tonic-gate 			return (NULL);
3917c478bd9Sstevel@tonic-gate 		}
3927c478bd9Sstevel@tonic-gate 		cp += skip + QFIXEDSZ;
3937c478bd9Sstevel@tonic-gate 	}
3947c478bd9Sstevel@tonic-gate 
3957c478bd9Sstevel@tonic-gate 	list = malloc((ancount + 1) * sizeof(char *));
3967c478bd9Sstevel@tonic-gate 	if (!list) {
3977c478bd9Sstevel@tonic-gate 		errno = ENOMEM;
3987c478bd9Sstevel@tonic-gate 		return (NULL);
3997c478bd9Sstevel@tonic-gate 	}
4007c478bd9Sstevel@tonic-gate 	j = 0;
4017c478bd9Sstevel@tonic-gate 	for (i = 0; i < ancount; i++) {
4027c478bd9Sstevel@tonic-gate 		skip = dn_skipname(cp, eom);
4037c478bd9Sstevel@tonic-gate 		if (skip < 0) {
4047c478bd9Sstevel@tonic-gate 			errno = EMSGSIZE;
4057c478bd9Sstevel@tonic-gate 			goto cleanup;
4067c478bd9Sstevel@tonic-gate 		}
4077c478bd9Sstevel@tonic-gate 		cp += skip;
4087c478bd9Sstevel@tonic-gate 		if (cp + 3 * INT16SZ + INT32SZ > eom) {
4097c478bd9Sstevel@tonic-gate 			errno = EMSGSIZE;
4107c478bd9Sstevel@tonic-gate 			goto cleanup;
4117c478bd9Sstevel@tonic-gate 		}
4127c478bd9Sstevel@tonic-gate 		rr.type = ns_get16(cp);
4137c478bd9Sstevel@tonic-gate 		cp += INT16SZ;
4147c478bd9Sstevel@tonic-gate 		rr.class = ns_get16(cp);
415*9525b14bSRao Shoaib 		cp += INT16SZ + INT32SZ;	/*%< skip the ttl, too */
4167c478bd9Sstevel@tonic-gate 		rr.dlen = ns_get16(cp);
4177c478bd9Sstevel@tonic-gate 		cp += INT16SZ;
4187c478bd9Sstevel@tonic-gate 		if (cp + rr.dlen > eom) {
4197c478bd9Sstevel@tonic-gate 			errno = EMSGSIZE;
4207c478bd9Sstevel@tonic-gate 			goto cleanup;
4217c478bd9Sstevel@tonic-gate 		}
4227c478bd9Sstevel@tonic-gate 		rr.data = cp;
4237c478bd9Sstevel@tonic-gate 		cp += rr.dlen;
4247c478bd9Sstevel@tonic-gate 		if (rr.class != class || rr.type != T_TXT)
4257c478bd9Sstevel@tonic-gate 			continue;
4267c478bd9Sstevel@tonic-gate 		if (!(list[j] = malloc(rr.dlen)))
4277c478bd9Sstevel@tonic-gate 			goto cleanup;
4287c478bd9Sstevel@tonic-gate 		dst = list[j++];
4297c478bd9Sstevel@tonic-gate 		edst = dst + rr.dlen;
4307c478bd9Sstevel@tonic-gate 		erdata = rr.data + rr.dlen;
4317c478bd9Sstevel@tonic-gate 		cp = rr.data;
4327c478bd9Sstevel@tonic-gate 		while (cp < erdata) {
4337c478bd9Sstevel@tonic-gate 			n = (unsigned char) *cp++;
4347c478bd9Sstevel@tonic-gate 			if (cp + n > eom || dst + n > edst) {
4357c478bd9Sstevel@tonic-gate 				errno = EMSGSIZE;
4367c478bd9Sstevel@tonic-gate 				goto cleanup;
4377c478bd9Sstevel@tonic-gate 			}
4387c478bd9Sstevel@tonic-gate 			memcpy(dst, cp, n);
4397c478bd9Sstevel@tonic-gate 			cp += n;
4407c478bd9Sstevel@tonic-gate 			dst += n;
4417c478bd9Sstevel@tonic-gate 		}
4427c478bd9Sstevel@tonic-gate 		if (cp != erdata) {
4437c478bd9Sstevel@tonic-gate 			errno = EMSGSIZE;
4447c478bd9Sstevel@tonic-gate 			goto cleanup;
4457c478bd9Sstevel@tonic-gate 		}
4467c478bd9Sstevel@tonic-gate 		*dst = '\0';
4477c478bd9Sstevel@tonic-gate 	}
4487c478bd9Sstevel@tonic-gate 	list[j] = NULL;
4497c478bd9Sstevel@tonic-gate 	if (j == 0) {
4507c478bd9Sstevel@tonic-gate 		errno = ENOENT;
4517c478bd9Sstevel@tonic-gate 		goto cleanup;
4527c478bd9Sstevel@tonic-gate 	}
4537c478bd9Sstevel@tonic-gate 	return (list);
4547c478bd9Sstevel@tonic-gate 
4557c478bd9Sstevel@tonic-gate  cleanup:
4567c478bd9Sstevel@tonic-gate 	for (i = 0; i < j; i++)
4577c478bd9Sstevel@tonic-gate 		free(list[i]);
4587c478bd9Sstevel@tonic-gate 	free(list);
4597c478bd9Sstevel@tonic-gate 	return (NULL);
4607c478bd9Sstevel@tonic-gate }
4617c478bd9Sstevel@tonic-gate 
4627c478bd9Sstevel@tonic-gate struct __res_state *
4637c478bd9Sstevel@tonic-gate __hesiod_res_get(void *context) {
4647c478bd9Sstevel@tonic-gate 	struct hesiod_p *ctx = context;
4657c478bd9Sstevel@tonic-gate 
4667c478bd9Sstevel@tonic-gate 	if (!ctx->res) {
4677c478bd9Sstevel@tonic-gate 		struct __res_state *res;
4687c478bd9Sstevel@tonic-gate 		res = (struct __res_state *)malloc(sizeof *res);
4697c478bd9Sstevel@tonic-gate 		if (res == NULL) {
4707c478bd9Sstevel@tonic-gate 			errno = ENOMEM;
4717c478bd9Sstevel@tonic-gate 			return (NULL);
4727c478bd9Sstevel@tonic-gate 		}
4737c478bd9Sstevel@tonic-gate 		memset(res, 0, sizeof *res);
4747c478bd9Sstevel@tonic-gate 		__hesiod_res_set(ctx, res, free);
4757c478bd9Sstevel@tonic-gate 	}
4767c478bd9Sstevel@tonic-gate 
4777c478bd9Sstevel@tonic-gate 	return (ctx->res);
4787c478bd9Sstevel@tonic-gate }
4797c478bd9Sstevel@tonic-gate 
4807c478bd9Sstevel@tonic-gate void
4817c478bd9Sstevel@tonic-gate __hesiod_res_set(void *context, struct __res_state *res,
4827c478bd9Sstevel@tonic-gate 	         void (*free_res)(void *)) {
4837c478bd9Sstevel@tonic-gate 	struct hesiod_p *ctx = context;
4847c478bd9Sstevel@tonic-gate 
4857c478bd9Sstevel@tonic-gate 	if (ctx->res && ctx->free_res) {
4867c478bd9Sstevel@tonic-gate 		res_nclose(ctx->res);
4877c478bd9Sstevel@tonic-gate 		(*ctx->free_res)(ctx->res);
4887c478bd9Sstevel@tonic-gate 	}
4897c478bd9Sstevel@tonic-gate 
4907c478bd9Sstevel@tonic-gate 	ctx->res = res;
4917c478bd9Sstevel@tonic-gate 	ctx->free_res = free_res;
4927c478bd9Sstevel@tonic-gate }
4937c478bd9Sstevel@tonic-gate 
4947c478bd9Sstevel@tonic-gate static int
4957c478bd9Sstevel@tonic-gate init(struct hesiod_p *ctx) {
4967c478bd9Sstevel@tonic-gate 
4977c478bd9Sstevel@tonic-gate 	if (!ctx->res && !__hesiod_res_get(ctx))
4987c478bd9Sstevel@tonic-gate 		return (-1);
4997c478bd9Sstevel@tonic-gate 
500*9525b14bSRao Shoaib 	if (((ctx->res->options & RES_INIT) == 0U) &&
5017c478bd9Sstevel@tonic-gate 	    (res_ninit(ctx->res) == -1))
5027c478bd9Sstevel@tonic-gate 		return (-1);
5037c478bd9Sstevel@tonic-gate 
5047c478bd9Sstevel@tonic-gate 	return (0);
5057c478bd9Sstevel@tonic-gate }
506