[openssh.git] / hostfile.c

/* $OpenBSD: hostfile.c,v 1.43 2006/07/26 13:57:17 stevesk Exp $ */
/*
 * Author: Tatu Ylonen <ylo@cs.hut.fi>
 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
 *                    All rights reserved
 * Functions for manipulating the known hosts files.
 *
 * As far as I am concerned, the code I have written for this software
 * can be used freely for any purpose.  Any derived versions of this
 * software must be clearly marked as such, and if the derived work is
 * incompatible with the protocol description in the RFC file, it must be
 * called by a name other than "ssh" or "Secure Shell".
 *
 *
 * Copyright (c) 1999, 2000 Markus Friedl.  All rights reserved.
 * Copyright (c) 1999 Niels Provos.  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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 "includes.h"

#include <sys/types.h>

#include <netinet/in.h>

#include <openssl/hmac.h>
#include <openssl/sha.h>

#include <resolv.h>
#include <stdlib.h>
#include <string.h>

#include "match.h"
#include "key.h"
#include "hostfile.h"
#include "log.h"
#include "xmalloc.h"

static int
extract_salt(const char *s, u_int l, char *salt, size_t salt_len)
{
	char *p, *b64salt;
	u_int b64len;
	int ret;

	if (l < sizeof(HASH_MAGIC) - 1) {
		debug2("extract_salt: string too short");
		return (-1);
	}
	if (strncmp(s, HASH_MAGIC, sizeof(HASH_MAGIC) - 1) != 0) {
		debug2("extract_salt: invalid magic identifier");
		return (-1);
	}
	s += sizeof(HASH_MAGIC) - 1;
	l -= sizeof(HASH_MAGIC) - 1;
	if ((p = memchr(s, HASH_DELIM, l)) == NULL) {
		debug2("extract_salt: missing salt termination character");
		return (-1);
	}

	b64len = p - s;
	/* Sanity check */
	if (b64len == 0 || b64len > 1024) {
		debug2("extract_salt: bad encoded salt length %u", b64len);
		return (-1);
	}
	b64salt = xmalloc(1 + b64len);
	memcpy(b64salt, s, b64len);
	b64salt[b64len] = '\0';

	ret = __b64_pton(b64salt, salt, salt_len);
	xfree(b64salt);
	if (ret == -1) {
		debug2("extract_salt: salt decode error");
		return (-1);
	}
	if (ret != SHA_DIGEST_LENGTH) {
		debug2("extract_salt: expected salt len %d, got %d",
		    SHA_DIGEST_LENGTH, ret);
		return (-1);
	}

	return (0);
}

char *
host_hash(const char *host, const char *name_from_hostfile, u_int src_len)
{
	const EVP_MD *md = EVP_sha1();
	HMAC_CTX mac_ctx;
	char salt[256], result[256], uu_salt[512], uu_result[512];
	static char encoded[1024];
	u_int i, len;

	len = EVP_MD_size(md);

	if (name_from_hostfile == NULL) {
		/* Create new salt */
		for (i = 0; i < len; i++)
			salt[i] = arc4random();
	} else {
		/* Extract salt from known host entry */
		if (extract_salt(name_from_hostfile, src_len, salt,
		    sizeof(salt)) == -1)
			return (NULL);
	}

	HMAC_Init(&mac_ctx, salt, len, md);
	HMAC_Update(&mac_ctx, host, strlen(host));
	HMAC_Final(&mac_ctx, result, NULL);
	HMAC_cleanup(&mac_ctx);

	if (__b64_ntop(salt, len, uu_salt, sizeof(uu_salt)) == -1 ||
	    __b64_ntop(result, len, uu_result, sizeof(uu_result)) == -1)
		fatal("host_hash: __b64_ntop failed");

	snprintf(encoded, sizeof(encoded), "%s%s%c%s", HASH_MAGIC, uu_salt,
	    HASH_DELIM, uu_result);

	return (encoded);
}

/*
 * Parses an RSA (number of bits, e, n) or DSA key from a string.  Moves the
 * pointer over the key.  Skips any whitespace at the beginning and at end.
 */

int
hostfile_read_key(char **cpp, u_int *bitsp, Key *ret)
{
	char *cp;

	/* Skip leading whitespace. */
	for (cp = *cpp; *cp == ' ' || *cp == '\t'; cp++)
		;

	if (key_read(ret, &cp) != 1)
		return 0;

	/* Skip trailing whitespace. */
	for (; *cp == ' ' || *cp == '\t'; cp++)
		;

	/* Return results. */
	*cpp = cp;
	*bitsp = key_size(ret);
	return 1;
}

static int
hostfile_check_key(int bits, const Key *key, const char *host, const char *filename, int linenum)
{
	if (key == NULL || key->type != KEY_RSA1 || key->rsa == NULL)
		return 1;
	if (bits != BN_num_bits(key->rsa->n)) {
		logit("Warning: %s, line %d: keysize mismatch for host %s: "
		    "actual %d vs. announced %d.",
		    filename, linenum, host, BN_num_bits(key->rsa->n), bits);
		logit("Warning: replace %d with %d in %s, line %d.",
		    bits, BN_num_bits(key->rsa->n), filename, linenum);
	}
	return 1;
}

/*
 * Checks whether the given host (which must be in all lowercase) is already
 * in the list of our known hosts. Returns HOST_OK if the host is known and
 * has the specified key, HOST_NEW if the host is not known, and HOST_CHANGED
 * if the host is known but used to have a different host key.
 *
 * If no 'key' has been specified and a key of type 'keytype' is known
 * for the specified host, then HOST_FOUND is returned.
 */

static HostStatus
check_host_in_hostfile_by_key_or_type(const char *filename,
    const char *host, const Key *key, int keytype, Key *found, int *numret)
{
	FILE *f;
	char line[8192];
	int linenum = 0;
	u_int kbits;
	char *cp, *cp2, *hashed_host;
	HostStatus end_return;

	debug3("check_host_in_hostfile: filename %s", filename);

	/* Open the file containing the list of known hosts. */
	f = fopen(filename, "r");
	if (!f)
		return HOST_NEW;

	/*
	 * Return value when the loop terminates.  This is set to
	 * HOST_CHANGED if we have seen a different key for the host and have
	 * not found the proper one.
	 */
	end_return = HOST_NEW;

	/* Go through the file. */
	while (fgets(line, sizeof(line), f)) {
		cp = line;
		linenum++;

		/* Skip any leading whitespace, comments and empty lines. */
		for (; *cp == ' ' || *cp == '\t'; cp++)
			;
		if (!*cp || *cp == '#' || *cp == '\n')
			continue;

		/* Find the end of the host name portion. */
		for (cp2 = cp; *cp2 && *cp2 != ' ' && *cp2 != '\t'; cp2++)
			;

		/* Check if the host name matches. */
		if (match_hostname(host, cp, (u_int) (cp2 - cp)) != 1) {
			if (*cp != HASH_DELIM)
				continue;
			hashed_host = host_hash(host, cp, (u_int) (cp2 - cp));
			if (hashed_host == NULL) {
				debug("Invalid hashed host line %d of %s",
				    linenum, filename);
				continue;
			}
			if (strncmp(hashed_host, cp, (u_int) (cp2 - cp)) != 0)
				continue;
		}

		/* Got a match.  Skip host name. */
		cp = cp2;

		/*
		 * Extract the key from the line.  This will skip any leading
		 * whitespace.  Ignore badly formatted lines.
		 */
		if (!hostfile_read_key(&cp, &kbits, found))
			continue;

		if (numret != NULL)
			*numret = linenum;

		if (key == NULL) {
			/* we found a key of the requested type */
			if (found->type == keytype) {
				fclose(f);
				return HOST_FOUND;
			}
			continue;
		}

		if (!hostfile_check_key(kbits, found, host, filename, linenum))
			continue;

		/* Check if the current key is the same as the given key. */
		if (key_equal(key, found)) {
			/* Ok, they match. */
			debug3("check_host_in_hostfile: match line %d", linenum);
			fclose(f);
			return HOST_OK;
		}
		/*
		 * They do not match.  We will continue to go through the
		 * file; however, we note that we will not return that it is
		 * new.
		 */
		end_return = HOST_CHANGED;
	}
	/* Clear variables and close the file. */
	fclose(f);

	/*
	 * Return either HOST_NEW or HOST_CHANGED, depending on whether we
	 * saw a different key for the host.
	 */
	return end_return;
}

HostStatus
check_host_in_hostfile(const char *filename, const char *host, const Key *key,
    Key *found, int *numret)
{
	if (key == NULL)
		fatal("no key to look up");
	return (check_host_in_hostfile_by_key_or_type(filename, host, key, 0,
	    found, numret));
}

int
lookup_key_in_hostfile_by_type(const char *filename, const char *host,
    int keytype, Key *found, int *numret)
{
	return (check_host_in_hostfile_by_key_or_type(filename, host, NULL,
	    keytype, found, numret) == HOST_FOUND);
}

/*
 * Appends an entry to the host file.  Returns false if the entry could not
 * be appended.
 */

int
add_host_to_hostfile(const char *filename, const char *host, const Key *key,
    int store_hash)
{
	FILE *f;
	int success = 0;
	char *hashed_host = NULL;

	if (key == NULL)
		return 1;	/* XXX ? */
	f = fopen(filename, "a");
	if (!f)
		return 0;

	if (store_hash) {
		if ((hashed_host = host_hash(host, NULL, 0)) == NULL) {
			error("add_host_to_hostfile: host_hash failed");
			fclose(f);
			return 0;
		}
	}
	fprintf(f, "%s ", store_hash ? hashed_host : host);

	if (key_write(key, f)) {
		success = 1;
	} else {
		error("add_host_to_hostfile: saving key in %s failed", filename);
	}
	fprintf(f, "\n");
	fclose(f);
	return success;
}
Commit	Line	Data
ffa517a8	1	/* $OpenBSD: hostfile.c,v 1.43 2006/07/26 13:57:17 stevesk Exp $ */
8efc0c15	2	/*
5260325f	3	* Author: Tatu Ylonen <ylo@cs.hut.fi>
5260325f	4	* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5260325f	5	* All rights reserved
bcbf86ec	6	* Functions for manipulating the known hosts files.
6ae2364d	7	*
bcbf86ec	8	* As far as I am concerned, the code I have written for this software
	9	* can be used freely for any purpose. Any derived versions of this
	10	* software must be clearly marked as such, and if the derived work is
	11	* incompatible with the protocol description in the RFC file, it must be
	12	* called by a name other than "ssh" or "Secure Shell".
6ae2364d	13	*
6ae2364d	14	*
a96070d4	15	* Copyright (c) 1999, 2000 Markus Friedl. All rights reserved.
bcbf86ec	16	* Copyright (c) 1999 Niels Provos. All rights reserved.
	17	*
	18	* Redistribution and use in source and binary forms, with or without
	19	* modification, are permitted provided that the following conditions
	20	* are met:
	21	* 1. Redistributions of source code must retain the above copyright
	22	* notice, this list of conditions and the following disclaimer.
	23	* 2. Redistributions in binary form must reproduce the above copyright
	24	* notice, this list of conditions and the following disclaimer in the
	25	* documentation and/or other materials provided with the distribution.
	26	*
	27	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
	28	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	29	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	30	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	31	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	32	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	33	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	34	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	35	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	36	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
5260325f	37	*/
8efc0c15	38
8efc0c15	39	#include "includes.h"
5c63c2ab	40
9794d008	41	#include <sys/types.h>
	42
	43	#include <netinet/in.h>
	44
5c63c2ab	45	#include <openssl/hmac.h>
5c63c2ab	46	#include <openssl/sha.h>
4fe2af09	47
ffa517a8	48	#include <resolv.h>
	49	#include <stdlib.h>
	50	#include <string.h>
	51
4fe2af09	52	#include "match.h"
4fe2af09	53	#include "key.h"
4fe2af09	54	#include "hostfile.h"
42f11eb2	55	#include "log.h"
5c63c2ab	56	#include "xmalloc.h"
	57
	58	static int
	59	extract_salt(const char s, u_int l, char salt, size_t salt_len)
	60	{
	61	char p, b64salt;
	62	u_int b64len;
	63	int ret;
	64
	65	if (l < sizeof(HASH_MAGIC) - 1) {
	66	debug2("extract_salt: string too short");
	67	return (-1);
	68	}
	69	if (strncmp(s, HASH_MAGIC, sizeof(HASH_MAGIC) - 1) != 0) {
	70	debug2("extract_salt: invalid magic identifier");
	71	return (-1);
	72	}
	73	s += sizeof(HASH_MAGIC) - 1;
	74	l -= sizeof(HASH_MAGIC) - 1;
	75	if ((p = memchr(s, HASH_DELIM, l)) == NULL) {
	76	debug2("extract_salt: missing salt termination character");
	77	return (-1);
	78	}
	79
	80	b64len = p - s;
	81	/* Sanity check */
	82	if (b64len == 0 \|\| b64len > 1024) {
	83	debug2("extract_salt: bad encoded salt length %u", b64len);
	84	return (-1);
	85	}
	86	b64salt = xmalloc(1 + b64len);
	87	memcpy(b64salt, s, b64len);
	88	b64salt[b64len] = '\0';
	89
	90	ret = __b64_pton(b64salt, salt, salt_len);
	91	xfree(b64salt);
	92	if (ret == -1) {
	93	debug2("extract_salt: salt decode error");
	94	return (-1);
	95	}
	96	if (ret != SHA_DIGEST_LENGTH) {
18f8ef7a	97	debug2("extract_salt: expected salt len %d, got %d",
18f8ef7a	98	SHA_DIGEST_LENGTH, ret);
5c63c2ab	99	return (-1);
5c63c2ab	100	}
f8cc7664	101
5c63c2ab	102	return (0);
	103	}
	104
	105	char *
	106	host_hash(const char host, const char name_from_hostfile, u_int src_len)
	107	{
	108	const EVP_MD *md = EVP_sha1();
	109	HMAC_CTX mac_ctx;
	110	char salt[256], result[256], uu_salt[512], uu_result[512];
	111	static char encoded[1024];
	112	u_int i, len;
	113
	114	len = EVP_MD_size(md);
	115
	116	if (name_from_hostfile == NULL) {
	117	/* Create new salt */
	118	for (i = 0; i < len; i++)
	119	salt[i] = arc4random();
	120	} else {
	121	/* Extract salt from known host entry */
	122	if (extract_salt(name_from_hostfile, src_len, salt,
	123	sizeof(salt)) == -1)
	124	return (NULL);
	125	}
	126
	127	HMAC_Init(&mac_ctx, salt, len, md);
	128	HMAC_Update(&mac_ctx, host, strlen(host));
	129	HMAC_Final(&mac_ctx, result, NULL);
	130	HMAC_cleanup(&mac_ctx);
	131
f8cc7664	132	if (__b64_ntop(salt, len, uu_salt, sizeof(uu_salt)) == -1 \|\|
5c63c2ab	133	__b64_ntop(result, len, uu_result, sizeof(uu_result)) == -1)
	134	fatal("host_hash: __b64_ntop failed");
	135
	136	snprintf(encoded, sizeof(encoded), "%s%s%c%s", HASH_MAGIC, uu_salt,
	137	HASH_DELIM, uu_result);
	138
	139	return (encoded);
	140	}
8efc0c15	141
aa3378df	142	/*
4fe2af09	143	* Parses an RSA (number of bits, e, n) or DSA key from a string. Moves the
4fe2af09	144	* pointer over the key. Skips any whitespace at the beginning and at end.
aa3378df	145	*/
8efc0c15	146
fb396518	147	int
1e3b8b07	148	hostfile_read_key(char *cpp, u_int bitsp, Key *ret)
8efc0c15	149	{
5260325f	150	char *cp;
	151
	152	/* Skip leading whitespace. */
aa3378df	153	for (cp = cpp; cp == ' ' \|\| *cp == '\t'; cp++)
aa3378df	154	;
5260325f	155
fa08c86b	156	if (key_read(ret, &cp) != 1)
5260325f	157	return 0;
	158
	159	/* Skip trailing whitespace. */
aa3378df	160	for (; cp == ' ' \|\| cp == '\t'; cp++)
aa3378df	161	;
5260325f	162
	163	/* Return results. */
	164	*cpp = cp;
fa08c86b	165	*bitsp = key_size(ret);
5260325f	166	return 1;
8efc0c15	167	}
8efc0c15	168
396c147e	169	static int
b6c7b7b7	170	hostfile_check_key(int bits, const Key key, const char host, const char *filename, int linenum)
4fe2af09	171	{
fa08c86b	172	if (key == NULL \|\| key->type != KEY_RSA1 \|\| key->rsa == NULL)
4fe2af09	173	return 1;
4fe2af09	174	if (bits != BN_num_bits(key->rsa->n)) {
bbe88b6d	175	logit("Warning: %s, line %d: keysize mismatch for host %s: "
4fe2af09	176	"actual %d vs. announced %d.",
4fe2af09	177	filename, linenum, host, BN_num_bits(key->rsa->n), bits);
bbe88b6d	178	logit("Warning: replace %d with %d in %s, line %d.",
4fe2af09	179	bits, BN_num_bits(key->rsa->n), filename, linenum);
8efc0c15	180	}
4fe2af09	181	return 1;
8efc0c15	182	}
8efc0c15	183
aa3378df	184	/*
	185	* Checks whether the given host (which must be in all lowercase) is already
	186	* in the list of our known hosts. Returns HOST_OK if the host is known and
	187	* has the specified key, HOST_NEW if the host is not known, and HOST_CHANGED
	188	* if the host is known but used to have a different host key.
8a48a7ef	189	*
	190	* If no 'key' has been specified and a key of type 'keytype' is known
	191	* for the specified host, then HOST_FOUND is returned.
aa3378df	192	*/
8efc0c15	193
8a48a7ef	194	static HostStatus
8a48a7ef	195	check_host_in_hostfile_by_key_or_type(const char *filename,
b6c7b7b7	196	const char host, const Key key, int keytype, Key found, int numret)
8efc0c15	197	{
5260325f	198	FILE *f;
	199	char line[8192];
	200	int linenum = 0;
d9d49fdb	201	u_int kbits;
5c63c2ab	202	char cp, cp2, *hashed_host;
5260325f	203	HostStatus end_return;
5260325f	204
8002af61	205	debug3("check_host_in_hostfile: filename %s", filename);
8a48a7ef	206
5260325f	207	/* Open the file containing the list of known hosts. */
	208	f = fopen(filename, "r");
	209	if (!f)
	210	return HOST_NEW;
	211
aa3378df	212	/*
	213	* Return value when the loop terminates. This is set to
	214	* HOST_CHANGED if we have seen a different key for the host and have
	215	* not found the proper one.
	216	*/
5260325f	217	end_return = HOST_NEW;
5260325f	218
d9d49fdb	219	/* Go through the file. */
5260325f	220	while (fgets(line, sizeof(line), f)) {
	221	cp = line;
	222	linenum++;
	223
aa3378df	224	/* Skip any leading whitespace, comments and empty lines. */
	225	for (; cp == ' ' \|\| cp == '\t'; cp++)
	226	;
5260325f	227	if (!cp \|\| cp == '#' \|\| *cp == '\n')
	228	continue;
	229
	230	/* Find the end of the host name portion. */
aa3378df	231	for (cp2 = cp; cp2 && cp2 != ' ' && *cp2 != '\t'; cp2++)
aa3378df	232	;
5260325f	233
5260325f	234	/* Check if the host name matches. */
5c63c2ab	235	if (match_hostname(host, cp, (u_int) (cp2 - cp)) != 1) {
	236	if (*cp != HASH_DELIM)
	237	continue;
	238	hashed_host = host_hash(host, cp, (u_int) (cp2 - cp));
	239	if (hashed_host == NULL) {
	240	debug("Invalid hashed host line %d of %s",
	241	linenum, filename);
	242	continue;
	243	}
	244	if (strncmp(hashed_host, cp, (u_int) (cp2 - cp)) != 0)
	245	continue;
	246	}
5260325f	247
	248	/* Got a match. Skip host name. */
	249	cp = cp2;
	250
aa3378df	251	/*
	252	* Extract the key from the line. This will skip any leading
	253	* whitespace. Ignore badly formatted lines.
	254	*/
4fe2af09	255	if (!hostfile_read_key(&cp, &kbits, found))
4fe2af09	256	continue;
5260325f	257
1e3b8b07	258	if (numret != NULL)
	259	*numret = linenum;
	260
8a48a7ef	261	if (key == NULL) {
8a48a7ef	262	/* we found a key of the requested type */
f8f9ef4d	263	if (found->type == keytype) {
f8f9ef4d	264	fclose(f);
8a48a7ef	265	return HOST_FOUND;
f8f9ef4d	266	}
8a48a7ef	267	continue;
	268	}
	269
	270	if (!hostfile_check_key(kbits, found, host, filename, linenum))
	271	continue;
	272
5260325f	273	/* Check if the current key is the same as the given key. */
4fe2af09	274	if (key_equal(key, found)) {
5260325f	275	/* Ok, they match. */
8002af61	276	debug3("check_host_in_hostfile: match line %d", linenum);
5260325f	277	fclose(f);
	278	return HOST_OK;
	279	}
aa3378df	280	/*
	281	* They do not match. We will continue to go through the
	282	* file; however, we note that we will not return that it is
	283	* new.
	284	*/
5260325f	285	end_return = HOST_CHANGED;
8efc0c15	286	}
5260325f	287	/* Clear variables and close the file. */
	288	fclose(f);
	289
aa3378df	290	/*
	291	* Return either HOST_NEW or HOST_CHANGED, depending on whether we
	292	* saw a different key for the host.
	293	*/
5260325f	294	return end_return;
8efc0c15	295	}
8efc0c15	296
8a48a7ef	297	HostStatus
b6c7b7b7	298	check_host_in_hostfile(const char filename, const char host, const Key *key,
8a48a7ef	299	Key found, int numret)
	300	{
	301	if (key == NULL)
	302	fatal("no key to look up");
	303	return (check_host_in_hostfile_by_key_or_type(filename, host, key, 0,
	304	found, numret));
	305	}
	306
	307	int
	308	lookup_key_in_hostfile_by_type(const char filename, const char host,
	309	int keytype, Key found, int numret)
	310	{
	311	return (check_host_in_hostfile_by_key_or_type(filename, host, NULL,
	312	keytype, found, numret) == HOST_FOUND);
	313	}
	314
aa3378df	315	/*
	316	* Appends an entry to the host file. Returns false if the entry could not
	317	* be appended.
	318	*/
8efc0c15	319
8efc0c15	320	int
f8cc7664	321	add_host_to_hostfile(const char filename, const char host, const Key *key,
5c63c2ab	322	int store_hash)
8efc0c15	323	{
5260325f	324	FILE *f;
4fe2af09	325	int success = 0;
a056dfa2	326	char *hashed_host = NULL;
5c63c2ab	327
4fe2af09	328	if (key == NULL)
a306f2dd	329	return 1; /* XXX ? */
5260325f	330	f = fopen(filename, "a");
	331	if (!f)
	332	return 0;
5c63c2ab	333
	334	if (store_hash) {
	335	if ((hashed_host = host_hash(host, NULL, 0)) == NULL) {
	336	error("add_host_to_hostfile: host_hash failed");
	337	fclose(f);
	338	return 0;
	339	}
	340	}
	341	fprintf(f, "%s ", store_hash ? hashed_host : host);
	342
4fe2af09	343	if (key_write(key, f)) {
4fe2af09	344	success = 1;
4fe2af09	345	} else {
a306f2dd	346	error("add_host_to_hostfile: saving key in %s failed", filename);
5260325f	347	}
a306f2dd	348	fprintf(f, "\n");
5260325f	349	fclose(f);
4fe2af09	350	return success;
8efc0c15	351	}