[openssh.git] / hostfile.c

/* $OpenBSD: hostfile.c,v 1.42 2006/07/22 20:48:23 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 <resolv.h>
#include <string.h>

#include <openssl/hmac.h>
#include <openssl/sha.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
00146caa	1	/* $OpenBSD: hostfile.c,v 1.42 2006/07/22 20:48:23 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 <resolv.h>
00146caa	46	#include <string.h>
cc63c340	47
5c63c2ab	48	#include <openssl/hmac.h>
5c63c2ab	49	#include <openssl/sha.h>
4fe2af09	50
4fe2af09	51	#include "match.h"
4fe2af09	52	#include "key.h"
4fe2af09	53	#include "hostfile.h"
42f11eb2	54	#include "log.h"
5c63c2ab	55	#include "xmalloc.h"
	56
	57	static int
	58	extract_salt(const char s, u_int l, char salt, size_t salt_len)
	59	{
	60	char p, b64salt;
	61	u_int b64len;
	62	int ret;
	63
	64	if (l < sizeof(HASH_MAGIC) - 1) {
	65	debug2("extract_salt: string too short");
	66	return (-1);
	67	}
	68	if (strncmp(s, HASH_MAGIC, sizeof(HASH_MAGIC) - 1) != 0) {
	69	debug2("extract_salt: invalid magic identifier");
	70	return (-1);
	71	}
	72	s += sizeof(HASH_MAGIC) - 1;
	73	l -= sizeof(HASH_MAGIC) - 1;
	74	if ((p = memchr(s, HASH_DELIM, l)) == NULL) {
	75	debug2("extract_salt: missing salt termination character");
	76	return (-1);
	77	}
	78
	79	b64len = p - s;
	80	/* Sanity check */
	81	if (b64len == 0 \|\| b64len > 1024) {
	82	debug2("extract_salt: bad encoded salt length %u", b64len);
	83	return (-1);
	84	}
	85	b64salt = xmalloc(1 + b64len);
	86	memcpy(b64salt, s, b64len);
	87	b64salt[b64len] = '\0';
	88
	89	ret = __b64_pton(b64salt, salt, salt_len);
	90	xfree(b64salt);
	91	if (ret == -1) {
	92	debug2("extract_salt: salt decode error");
	93	return (-1);
	94	}
	95	if (ret != SHA_DIGEST_LENGTH) {
18f8ef7a	96	debug2("extract_salt: expected salt len %d, got %d",
18f8ef7a	97	SHA_DIGEST_LENGTH, ret);
5c63c2ab	98	return (-1);
5c63c2ab	99	}
f8cc7664	100
5c63c2ab	101	return (0);
	102	}
	103
	104	char *
	105	host_hash(const char host, const char name_from_hostfile, u_int src_len)
	106	{
	107	const EVP_MD *md = EVP_sha1();
	108	HMAC_CTX mac_ctx;
	109	char salt[256], result[256], uu_salt[512], uu_result[512];
	110	static char encoded[1024];
	111	u_int i, len;
	112
	113	len = EVP_MD_size(md);
	114
	115	if (name_from_hostfile == NULL) {
	116	/* Create new salt */
	117	for (i = 0; i < len; i++)
	118	salt[i] = arc4random();
	119	} else {
	120	/* Extract salt from known host entry */
	121	if (extract_salt(name_from_hostfile, src_len, salt,
	122	sizeof(salt)) == -1)
	123	return (NULL);
	124	}
	125
	126	HMAC_Init(&mac_ctx, salt, len, md);
	127	HMAC_Update(&mac_ctx, host, strlen(host));
	128	HMAC_Final(&mac_ctx, result, NULL);
	129	HMAC_cleanup(&mac_ctx);
	130
f8cc7664	131	if (__b64_ntop(salt, len, uu_salt, sizeof(uu_salt)) == -1 \|\|
5c63c2ab	132	__b64_ntop(result, len, uu_result, sizeof(uu_result)) == -1)
	133	fatal("host_hash: __b64_ntop failed");
	134
	135	snprintf(encoded, sizeof(encoded), "%s%s%c%s", HASH_MAGIC, uu_salt,
	136	HASH_DELIM, uu_result);
	137
	138	return (encoded);
	139	}
8efc0c15	140
aa3378df	141	/*
4fe2af09	142	* Parses an RSA (number of bits, e, n) or DSA key from a string. Moves the
4fe2af09	143	* pointer over the key. Skips any whitespace at the beginning and at end.
aa3378df	144	*/
8efc0c15	145
fb396518	146	int
1e3b8b07	147	hostfile_read_key(char *cpp, u_int bitsp, Key *ret)
8efc0c15	148	{
5260325f	149	char *cp;
	150
	151	/* Skip leading whitespace. */
aa3378df	152	for (cp = cpp; cp == ' ' \|\| *cp == '\t'; cp++)
aa3378df	153	;
5260325f	154
fa08c86b	155	if (key_read(ret, &cp) != 1)
5260325f	156	return 0;
	157
	158	/* Skip trailing whitespace. */
aa3378df	159	for (; cp == ' ' \|\| cp == '\t'; cp++)
aa3378df	160	;
5260325f	161
	162	/* Return results. */
	163	*cpp = cp;
fa08c86b	164	*bitsp = key_size(ret);
5260325f	165	return 1;
8efc0c15	166	}
8efc0c15	167
396c147e	168	static int
b6c7b7b7	169	hostfile_check_key(int bits, const Key key, const char host, const char *filename, int linenum)
4fe2af09	170	{
fa08c86b	171	if (key == NULL \|\| key->type != KEY_RSA1 \|\| key->rsa == NULL)
4fe2af09	172	return 1;
4fe2af09	173	if (bits != BN_num_bits(key->rsa->n)) {
bbe88b6d	174	logit("Warning: %s, line %d: keysize mismatch for host %s: "
4fe2af09	175	"actual %d vs. announced %d.",
4fe2af09	176	filename, linenum, host, BN_num_bits(key->rsa->n), bits);
bbe88b6d	177	logit("Warning: replace %d with %d in %s, line %d.",
4fe2af09	178	bits, BN_num_bits(key->rsa->n), filename, linenum);
8efc0c15	179	}
4fe2af09	180	return 1;
8efc0c15	181	}
8efc0c15	182
aa3378df	183	/*
	184	* Checks whether the given host (which must be in all lowercase) is already
	185	* in the list of our known hosts. Returns HOST_OK if the host is known and
	186	* has the specified key, HOST_NEW if the host is not known, and HOST_CHANGED
	187	* if the host is known but used to have a different host key.
8a48a7ef	188	*
	189	* If no 'key' has been specified and a key of type 'keytype' is known
	190	* for the specified host, then HOST_FOUND is returned.
aa3378df	191	*/
8efc0c15	192
8a48a7ef	193	static HostStatus
8a48a7ef	194	check_host_in_hostfile_by_key_or_type(const char *filename,
b6c7b7b7	195	const char host, const Key key, int keytype, Key found, int numret)
8efc0c15	196	{
5260325f	197	FILE *f;
	198	char line[8192];
	199	int linenum = 0;
d9d49fdb	200	u_int kbits;
5c63c2ab	201	char cp, cp2, *hashed_host;
5260325f	202	HostStatus end_return;
5260325f	203
8002af61	204	debug3("check_host_in_hostfile: filename %s", filename);
8a48a7ef	205
5260325f	206	/* Open the file containing the list of known hosts. */
	207	f = fopen(filename, "r");
	208	if (!f)
	209	return HOST_NEW;
	210
aa3378df	211	/*
	212	* Return value when the loop terminates. This is set to
	213	* HOST_CHANGED if we have seen a different key for the host and have
	214	* not found the proper one.
	215	*/
5260325f	216	end_return = HOST_NEW;
5260325f	217
d9d49fdb	218	/* Go through the file. */
5260325f	219	while (fgets(line, sizeof(line), f)) {
	220	cp = line;
	221	linenum++;
	222
aa3378df	223	/* Skip any leading whitespace, comments and empty lines. */
	224	for (; cp == ' ' \|\| cp == '\t'; cp++)
	225	;
5260325f	226	if (!cp \|\| cp == '#' \|\| *cp == '\n')
	227	continue;
	228
	229	/* Find the end of the host name portion. */
aa3378df	230	for (cp2 = cp; cp2 && cp2 != ' ' && *cp2 != '\t'; cp2++)
aa3378df	231	;
5260325f	232
5260325f	233	/* Check if the host name matches. */
5c63c2ab	234	if (match_hostname(host, cp, (u_int) (cp2 - cp)) != 1) {
	235	if (*cp != HASH_DELIM)
	236	continue;
	237	hashed_host = host_hash(host, cp, (u_int) (cp2 - cp));
	238	if (hashed_host == NULL) {
	239	debug("Invalid hashed host line %d of %s",
	240	linenum, filename);
	241	continue;
	242	}
	243	if (strncmp(hashed_host, cp, (u_int) (cp2 - cp)) != 0)
	244	continue;
	245	}
5260325f	246
	247	/* Got a match. Skip host name. */
	248	cp = cp2;
	249
aa3378df	250	/*
	251	* Extract the key from the line. This will skip any leading
	252	* whitespace. Ignore badly formatted lines.
	253	*/
4fe2af09	254	if (!hostfile_read_key(&cp, &kbits, found))
4fe2af09	255	continue;
5260325f	256
1e3b8b07	257	if (numret != NULL)
	258	*numret = linenum;
	259
8a48a7ef	260	if (key == NULL) {
8a48a7ef	261	/* we found a key of the requested type */
f8f9ef4d	262	if (found->type == keytype) {
f8f9ef4d	263	fclose(f);
8a48a7ef	264	return HOST_FOUND;
f8f9ef4d	265	}
8a48a7ef	266	continue;
	267	}
	268
	269	if (!hostfile_check_key(kbits, found, host, filename, linenum))
	270	continue;
	271
5260325f	272	/* Check if the current key is the same as the given key. */
4fe2af09	273	if (key_equal(key, found)) {
5260325f	274	/* Ok, they match. */
8002af61	275	debug3("check_host_in_hostfile: match line %d", linenum);
5260325f	276	fclose(f);
	277	return HOST_OK;
	278	}
aa3378df	279	/*
	280	* They do not match. We will continue to go through the
	281	* file; however, we note that we will not return that it is
	282	* new.
	283	*/
5260325f	284	end_return = HOST_CHANGED;
8efc0c15	285	}
5260325f	286	/* Clear variables and close the file. */
	287	fclose(f);
	288
aa3378df	289	/*
	290	* Return either HOST_NEW or HOST_CHANGED, depending on whether we
	291	* saw a different key for the host.
	292	*/
5260325f	293	return end_return;
8efc0c15	294	}
8efc0c15	295
8a48a7ef	296	HostStatus
b6c7b7b7	297	check_host_in_hostfile(const char filename, const char host, const Key *key,
8a48a7ef	298	Key found, int numret)
	299	{
	300	if (key == NULL)
	301	fatal("no key to look up");
	302	return (check_host_in_hostfile_by_key_or_type(filename, host, key, 0,
	303	found, numret));
	304	}
	305
	306	int
	307	lookup_key_in_hostfile_by_type(const char filename, const char host,
	308	int keytype, Key found, int numret)
	309	{
	310	return (check_host_in_hostfile_by_key_or_type(filename, host, NULL,
	311	keytype, found, numret) == HOST_FOUND);
	312	}
	313
aa3378df	314	/*
	315	* Appends an entry to the host file. Returns false if the entry could not
	316	* be appended.
	317	*/
8efc0c15	318
8efc0c15	319	int
f8cc7664	320	add_host_to_hostfile(const char filename, const char host, const Key *key,
5c63c2ab	321	int store_hash)
8efc0c15	322	{
5260325f	323	FILE *f;
4fe2af09	324	int success = 0;
a056dfa2	325	char *hashed_host = NULL;
5c63c2ab	326
4fe2af09	327	if (key == NULL)
a306f2dd	328	return 1; /* XXX ? */
5260325f	329	f = fopen(filename, "a");
	330	if (!f)
	331	return 0;
5c63c2ab	332
	333	if (store_hash) {
	334	if ((hashed_host = host_hash(host, NULL, 0)) == NULL) {
	335	error("add_host_to_hostfile: host_hash failed");
	336	fclose(f);
	337	return 0;
	338	}
	339	}
	340	fprintf(f, "%s ", store_hash ? hashed_host : host);
	341
4fe2af09	342	if (key_write(key, f)) {
4fe2af09	343	success = 1;
4fe2af09	344	} else {
a306f2dd	345	error("add_host_to_hostfile: saving key in %s failed", filename);
5260325f	346	}
a306f2dd	347	fprintf(f, "\n");
5260325f	348	fclose(f);
4fe2af09	349	return success;
8efc0c15	350	}