[openssh.git] / authfile.c

/*
 *
 * authfile.c
 *
 * Author: Tatu Ylonen <ylo@cs.hut.fi>
 *
 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
 *                    All rights reserved
 *
 * Created: Mon Mar 27 03:52:05 1995 ylo
 *
 * This file contains functions for reading and writing identity files, and
 * for reading the passphrase from the user.
 *
 */

#include "includes.h"
RCSID("$Id$");

#include <openssl/bn.h>
#include "xmalloc.h"
#include "buffer.h"
#include "bufaux.h"
#include "cipher.h"
#include "ssh.h"

/* Version identification string for identity files. */
#define AUTHFILE_ID_STRING "SSH PRIVATE KEY FILE FORMAT 1.1\n"

/*
 * Saves the authentication (private) key in a file, encrypting it with
 * passphrase.  The identification of the file (lowest 64 bits of n) will
 * precede the key to provide identification of the key without needing a
 * passphrase.
 */

int
save_private_key(const char *filename, const char *passphrase,
		 RSA *key, const char *comment)
{
	Buffer buffer, encrypted;
	char buf[100], *cp;
	int fd, i;
	CipherContext cipher;
	int cipher_type;
	u_int32_t rand;

	/*
	 * If the passphrase is empty, use SSH_CIPHER_NONE to ease converting
	 * to another cipher; otherwise use SSH_AUTHFILE_CIPHER.
	 */
	if (strcmp(passphrase, "") == 0)
		cipher_type = SSH_CIPHER_NONE;
	else
		cipher_type = SSH_AUTHFILE_CIPHER;

	/* This buffer is used to built the secret part of the private key. */
	buffer_init(&buffer);

	/* Put checkbytes for checking passphrase validity. */
	rand = arc4random();
	buf[0] = rand & 0xff;
	buf[1] = (rand >> 8) & 0xff;
	buf[2] = buf[0];
	buf[3] = buf[1];
	buffer_append(&buffer, buf, 4);

	/*
	 * Store the private key (n and e will not be stored because they
	 * will be stored in plain text, and storing them also in encrypted
	 * format would just give known plaintext).
	 */
	buffer_put_bignum(&buffer, key->d);
	buffer_put_bignum(&buffer, key->iqmp);
	buffer_put_bignum(&buffer, key->q);	/* reverse from SSL p */
	buffer_put_bignum(&buffer, key->p);	/* reverse from SSL q */

	/* Pad the part to be encrypted until its size is a multiple of 8. */
	while (buffer_len(&buffer) % 8 != 0)
		buffer_put_char(&buffer, 0);

	/* This buffer will be used to contain the data in the file. */
	buffer_init(&encrypted);

	/* First store keyfile id string. */
	cp = AUTHFILE_ID_STRING;
	for (i = 0; cp[i]; i++)
		buffer_put_char(&encrypted, cp[i]);
	buffer_put_char(&encrypted, 0);

	/* Store cipher type. */
	buffer_put_char(&encrypted, cipher_type);
	buffer_put_int(&encrypted, 0);	/* For future extension */

	/* Store public key.  This will be in plain text. */
	buffer_put_int(&encrypted, BN_num_bits(key->n));
	buffer_put_bignum(&encrypted, key->n);
	buffer_put_bignum(&encrypted, key->e);
	buffer_put_string(&encrypted, comment, strlen(comment));

	/* Allocate space for the private part of the key in the buffer. */
	buffer_append_space(&encrypted, &cp, buffer_len(&buffer));

	cipher_set_key_string(&cipher, cipher_type, passphrase);
	cipher_encrypt(&cipher, (unsigned char *) cp,
		       (unsigned char *) buffer_ptr(&buffer),
		       buffer_len(&buffer));
	memset(&cipher, 0, sizeof(cipher));

	/* Destroy temporary data. */
	memset(buf, 0, sizeof(buf));
	buffer_free(&buffer);

	fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600);
	if (fd < 0)
		return 0;
	if (write(fd, buffer_ptr(&encrypted), buffer_len(&encrypted)) !=
	    buffer_len(&encrypted)) {
		debug("Write to key file %.200s failed: %.100s", filename,
		      strerror(errno));
		buffer_free(&encrypted);
		close(fd);
		remove(filename);
		return 0;
	}
	close(fd);
	buffer_free(&encrypted);
	return 1;
}

/*
 * Loads the public part of the key file.  Returns 0 if an error was
 * encountered (the file does not exist or is not readable), and non-zero
 * otherwise.
 */

int
load_public_key(const char *filename, RSA * pub,
		char **comment_return)
{
	int fd, i;
	off_t len;
	Buffer buffer;
	char *cp;

	fd = open(filename, O_RDONLY);
	if (fd < 0)
		return 0;
	len = lseek(fd, (off_t) 0, SEEK_END);
	lseek(fd, (off_t) 0, SEEK_SET);

	buffer_init(&buffer);
	buffer_append_space(&buffer, &cp, len);

	if (read(fd, cp, (size_t) len) != (size_t) len) {
		debug("Read from key file %.200s failed: %.100s", filename,
		      strerror(errno));
		buffer_free(&buffer);
		close(fd);
		return 0;
	}
	close(fd);

	/* Check that it is at least big enought to contain the ID string. */
	if (len < strlen(AUTHFILE_ID_STRING) + 1) {
		debug("Bad key file %.200s.", filename);
		buffer_free(&buffer);
		return 0;
	}
	/*
	 * Make sure it begins with the id string.  Consume the id string
	 * from the buffer.
	 */
	for (i = 0; i < (unsigned int) strlen(AUTHFILE_ID_STRING) + 1; i++)
		if (buffer_get_char(&buffer) != (u_char) AUTHFILE_ID_STRING[i]) {
			debug("Bad key file %.200s.", filename);
			buffer_free(&buffer);
			return 0;
		}
	/* Skip cipher type and reserved data. */
	(void) buffer_get_char(&buffer);	/* cipher type */
	(void) buffer_get_int(&buffer);		/* reserved */

	/* Read the public key from the buffer. */
	buffer_get_int(&buffer);
	pub->n = BN_new();
	buffer_get_bignum(&buffer, pub->n);
	pub->e = BN_new();
	buffer_get_bignum(&buffer, pub->e);
	if (comment_return)
		*comment_return = buffer_get_string(&buffer, NULL);
	/* The encrypted private part is not parsed by this function. */

	buffer_free(&buffer);

	return 1;
}

/*
 * Loads the private key from the file.  Returns 0 if an error is encountered
 * (file does not exist or is not readable, or passphrase is bad). This
 * initializes the private key.
 * Assumes we are called under uid of the owner of the file.
 */

int
load_private_key(const char *filename, const char *passphrase,
		 RSA * prv, char **comment_return)
{
	int fd, i, check1, check2, cipher_type;
	off_t len;
	Buffer buffer, decrypted;
	char *cp;
	CipherContext cipher;
	BN_CTX *ctx;
	BIGNUM *aux;
	struct stat st;

	fd = open(filename, O_RDONLY);
	if (fd < 0)
		return 0;

	/* check owner and modes */
	if (fstat(fd, &st) < 0 ||
	    (st.st_uid != 0 && getuid() != 0 && st.st_uid != getuid()) ||
	    (st.st_mode & 077) != 0) {
		close(fd);
		error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
		error("@         WARNING: UNPROTECTED PRIVATE KEY FILE!          @");
		error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
		error("Bad ownership or mode(0%3.3o) for '%s'.",
		      st.st_mode & 0777, filename);
		error("It is recommended that your private key files are NOT accessible by others.");
		return 0;
	}
	len = lseek(fd, (off_t) 0, SEEK_END);
	lseek(fd, (off_t) 0, SEEK_SET);

	buffer_init(&buffer);
	buffer_append_space(&buffer, &cp, len);

	if (read(fd, cp, (size_t) len) != (size_t) len) {
		debug("Read from key file %.200s failed: %.100s", filename,
		      strerror(errno));
		buffer_free(&buffer);
		close(fd);
		return 0;
	}
	close(fd);

	/* Check that it is at least big enought to contain the ID string. */
	if (len < strlen(AUTHFILE_ID_STRING) + 1) {
		debug("Bad key file %.200s.", filename);
		buffer_free(&buffer);
		return 0;
	}
	/*
	 * Make sure it begins with the id string.  Consume the id string
	 * from the buffer.
	 */
	for (i = 0; i < (unsigned int) strlen(AUTHFILE_ID_STRING) + 1; i++)
		if (buffer_get_char(&buffer) != (unsigned char) AUTHFILE_ID_STRING[i]) {
			debug("Bad key file %.200s.", filename);
			buffer_free(&buffer);
			return 0;
		}
	/* Read cipher type. */
	cipher_type = buffer_get_char(&buffer);
	(void) buffer_get_int(&buffer);	/* Reserved data. */

	/* Read the public key from the buffer. */
	buffer_get_int(&buffer);
	prv->n = BN_new();
	buffer_get_bignum(&buffer, prv->n);
	prv->e = BN_new();
	buffer_get_bignum(&buffer, prv->e);
	if (comment_return)
		*comment_return = buffer_get_string(&buffer, NULL);
	else
		xfree(buffer_get_string(&buffer, NULL));

	/* Check that it is a supported cipher. */
	if (((cipher_mask1() | SSH_CIPHER_NONE | SSH_AUTHFILE_CIPHER) &
	     (1 << cipher_type)) == 0) {
		debug("Unsupported cipher %.100s used in key file %.200s.",
		      cipher_name(cipher_type), filename);
		buffer_free(&buffer);
		goto fail;
	}
	/* Initialize space for decrypted data. */
	buffer_init(&decrypted);
	buffer_append_space(&decrypted, &cp, buffer_len(&buffer));

	/* Rest of the buffer is encrypted.  Decrypt it using the passphrase. */
	cipher_set_key_string(&cipher, cipher_type, passphrase);
	cipher_decrypt(&cipher, (unsigned char *) cp,
		       (unsigned char *) buffer_ptr(&buffer),
		       buffer_len(&buffer));

	buffer_free(&buffer);

	check1 = buffer_get_char(&decrypted);
	check2 = buffer_get_char(&decrypted);
	if (check1 != buffer_get_char(&decrypted) ||
	    check2 != buffer_get_char(&decrypted)) {
		if (strcmp(passphrase, "") != 0)
			debug("Bad passphrase supplied for key file %.200s.", filename);
		/* Bad passphrase. */
		buffer_free(&decrypted);
fail:
		BN_clear_free(prv->n);
		BN_clear_free(prv->e);
		if (comment_return)
			xfree(*comment_return);
		return 0;
	}
	/* Read the rest of the private key. */
	prv->d = BN_new();
	buffer_get_bignum(&decrypted, prv->d);
	prv->iqmp = BN_new();
	buffer_get_bignum(&decrypted, prv->iqmp);	/* u */
	/* in SSL and SSH p and q are exchanged */
	prv->q = BN_new();
	buffer_get_bignum(&decrypted, prv->q);		/* p */
	prv->p = BN_new();
	buffer_get_bignum(&decrypted, prv->p);		/* q */

	ctx = BN_CTX_new();
	aux = BN_new();

	BN_sub(aux, prv->q, BN_value_one());
	prv->dmq1 = BN_new();
	BN_mod(prv->dmq1, prv->d, aux, ctx);

	BN_sub(aux, prv->p, BN_value_one());
	prv->dmp1 = BN_new();
	BN_mod(prv->dmp1, prv->d, aux, ctx);

	BN_clear_free(aux);
	BN_CTX_free(ctx);

	buffer_free(&decrypted);

	return 1;
}
Commit	Line	Data
8efc0c15	1	/*
6ae2364d	2	*
5260325f	3	* authfile.c
6ae2364d	4	*
5260325f	5	* Author: Tatu Ylonen <ylo@cs.hut.fi>
6ae2364d	6	*
5260325f	7	* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5260325f	8	* All rights reserved
6ae2364d	9	*
5260325f	10	* Created: Mon Mar 27 03:52:05 1995 ylo
6ae2364d	11	*
5260325f	12	* This file contains functions for reading and writing identity files, and
5260325f	13	* for reading the passphrase from the user.
6ae2364d	14	*
5260325f	15	*/
8efc0c15	16
	17	#include "includes.h"
	18	RCSID("$Id$");
	19
	20	#include <openssl/bn.h>
	21	#include "xmalloc.h"
	22	#include "buffer.h"
	23	#include "bufaux.h"
	24	#include "cipher.h"
	25	#include "ssh.h"
	26
	27	/* Version identification string for identity files. */
	28	#define AUTHFILE_ID_STRING "SSH PRIVATE KEY FILE FORMAT 1.1\n"
	29
aa3378df	30	/*
	31	* Saves the authentication (private) key in a file, encrypting it with
	32	* passphrase. The identification of the file (lowest 64 bits of n) will
	33	* precede the key to provide identification of the key without needing a
	34	* passphrase.
	35	*/
8efc0c15	36
	37	int
	38	save_private_key(const char filename, const char passphrase,
	39	RSA key, const char comment)
	40	{
5260325f	41	Buffer buffer, encrypted;
5260325f	42	char buf[100], *cp;
a408af76	43	int fd, i;
5260325f	44	CipherContext cipher;
	45	int cipher_type;
	46	u_int32_t rand;
	47
aa3378df	48	/*
	49	* If the passphrase is empty, use SSH_CIPHER_NONE to ease converting
	50	* to another cipher; otherwise use SSH_AUTHFILE_CIPHER.
	51	*/
5260325f	52	if (strcmp(passphrase, "") == 0)
	53	cipher_type = SSH_CIPHER_NONE;
	54	else
	55	cipher_type = SSH_AUTHFILE_CIPHER;
	56
	57	/* This buffer is used to built the secret part of the private key. */
	58	buffer_init(&buffer);
	59
	60	/* Put checkbytes for checking passphrase validity. */
	61	rand = arc4random();
	62	buf[0] = rand & 0xff;
	63	buf[1] = (rand >> 8) & 0xff;
	64	buf[2] = buf[0];
	65	buf[3] = buf[1];
	66	buffer_append(&buffer, buf, 4);
	67
aa3378df	68	/*
	69	* Store the private key (n and e will not be stored because they
	70	* will be stored in plain text, and storing them also in encrypted
	71	* format would just give known plaintext).
	72	*/
5260325f	73	buffer_put_bignum(&buffer, key->d);
	74	buffer_put_bignum(&buffer, key->iqmp);
	75	buffer_put_bignum(&buffer, key->q); /* reverse from SSL p */
	76	buffer_put_bignum(&buffer, key->p); /* reverse from SSL q */
	77
	78	/* Pad the part to be encrypted until its size is a multiple of 8. */
	79	while (buffer_len(&buffer) % 8 != 0)
	80	buffer_put_char(&buffer, 0);
	81
	82	/* This buffer will be used to contain the data in the file. */
	83	buffer_init(&encrypted);
	84
	85	/* First store keyfile id string. */
	86	cp = AUTHFILE_ID_STRING;
	87	for (i = 0; cp[i]; i++)
	88	buffer_put_char(&encrypted, cp[i]);
	89	buffer_put_char(&encrypted, 0);
	90
	91	/* Store cipher type. */
	92	buffer_put_char(&encrypted, cipher_type);
	93	buffer_put_int(&encrypted, 0); /* For future extension */
	94
	95	/* Store public key. This will be in plain text. */
	96	buffer_put_int(&encrypted, BN_num_bits(key->n));
	97	buffer_put_bignum(&encrypted, key->n);
	98	buffer_put_bignum(&encrypted, key->e);
	99	buffer_put_string(&encrypted, comment, strlen(comment));
	100
	101	/* Allocate space for the private part of the key in the buffer. */
	102	buffer_append_space(&encrypted, &cp, buffer_len(&buffer));
	103
8ce64345	104	cipher_set_key_string(&cipher, cipher_type, passphrase);
5260325f	105	cipher_encrypt(&cipher, (unsigned char *) cp,
	106	(unsigned char *) buffer_ptr(&buffer),
	107	buffer_len(&buffer));
	108	memset(&cipher, 0, sizeof(cipher));
	109
	110	/* Destroy temporary data. */
	111	memset(buf, 0, sizeof(buf));
	112	buffer_free(&buffer);
	113
a408af76	114	fd = open(filename, O_WRONLY \| O_CREAT \| O_TRUNC, 0600);
a408af76	115	if (fd < 0)
5260325f	116	return 0;
a408af76	117	if (write(fd, buffer_ptr(&encrypted), buffer_len(&encrypted)) !=
5260325f	118	buffer_len(&encrypted)) {
	119	debug("Write to key file %.200s failed: %.100s", filename,
	120	strerror(errno));
	121	buffer_free(&encrypted);
a408af76	122	close(fd);
5260325f	123	remove(filename);
	124	return 0;
	125	}
a408af76	126	close(fd);
5260325f	127	buffer_free(&encrypted);
5260325f	128	return 1;
8efc0c15	129	}
8efc0c15	130
aa3378df	131	/*
	132	* Loads the public part of the key file. Returns 0 if an error was
	133	* encountered (the file does not exist or is not readable), and non-zero
	134	* otherwise.
	135	*/
8efc0c15	136
8efc0c15	137	int
5260325f	138	load_public_key(const char filename, RSA pub,
8efc0c15	139	char **comment_return)
8efc0c15	140	{
a408af76	141	int fd, i;
5260325f	142	off_t len;
	143	Buffer buffer;
	144	char *cp;
	145
a408af76	146	fd = open(filename, O_RDONLY);
a408af76	147	if (fd < 0)
5260325f	148	return 0;
a408af76	149	len = lseek(fd, (off_t) 0, SEEK_END);
a408af76	150	lseek(fd, (off_t) 0, SEEK_SET);
5260325f	151
	152	buffer_init(&buffer);
	153	buffer_append_space(&buffer, &cp, len);
	154
a408af76	155	if (read(fd, cp, (size_t) len) != (size_t) len) {
5260325f	156	debug("Read from key file %.200s failed: %.100s", filename,
	157	strerror(errno));
	158	buffer_free(&buffer);
a408af76	159	close(fd);
5260325f	160	return 0;
5260325f	161	}
a408af76	162	close(fd);
5260325f	163
	164	/* Check that it is at least big enought to contain the ID string. */
	165	if (len < strlen(AUTHFILE_ID_STRING) + 1) {
	166	debug("Bad key file %.200s.", filename);
	167	buffer_free(&buffer);
	168	return 0;
	169	}
aa3378df	170	/*
	171	* Make sure it begins with the id string. Consume the id string
	172	* from the buffer.
	173	*/
5260325f	174	for (i = 0; i < (unsigned int) strlen(AUTHFILE_ID_STRING) + 1; i++)
a408af76	175	if (buffer_get_char(&buffer) != (u_char) AUTHFILE_ID_STRING[i]) {
5260325f	176	debug("Bad key file %.200s.", filename);
	177	buffer_free(&buffer);
	178	return 0;
	179	}
	180	/* Skip cipher type and reserved data. */
	181	(void) buffer_get_char(&buffer); /* cipher type */
	182	(void) buffer_get_int(&buffer); /* reserved */
	183
	184	/* Read the public key from the buffer. */
	185	buffer_get_int(&buffer);
	186	pub->n = BN_new();
	187	buffer_get_bignum(&buffer, pub->n);
	188	pub->e = BN_new();
	189	buffer_get_bignum(&buffer, pub->e);
	190	if (comment_return)
	191	*comment_return = buffer_get_string(&buffer, NULL);
	192	/* The encrypted private part is not parsed by this function. */
	193
8efc0c15	194	buffer_free(&buffer);
5260325f	195
5260325f	196	return 1;
8efc0c15	197	}
8efc0c15	198
aa3378df	199	/*
	200	* Loads the private key from the file. Returns 0 if an error is encountered
	201	* (file does not exist or is not readable, or passphrase is bad). This
	202	* initializes the private key.
	203	* Assumes we are called under uid of the owner of the file.
	204	*/
8efc0c15	205
	206	int
	207	load_private_key(const char filename, const char passphrase,
5260325f	208	RSA * prv, char **comment_return)
8efc0c15	209	{
a408af76	210	int fd, i, check1, check2, cipher_type;
5260325f	211	off_t len;
	212	Buffer buffer, decrypted;
	213	char *cp;
	214	CipherContext cipher;
	215	BN_CTX *ctx;
	216	BIGNUM *aux;
	217	struct stat st;
	218
a408af76	219	fd = open(filename, O_RDONLY);
a408af76	220	if (fd < 0)
5260325f	221	return 0;
5260325f	222
aa3378df	223	/* check owner and modes */
a408af76	224	if (fstat(fd, &st) < 0 \|\|
81eef326	225	(st.st_uid != 0 && getuid() != 0 && st.st_uid != getuid()) \|\|
5260325f	226	(st.st_mode & 077) != 0) {
a408af76	227	close(fd);
5260325f	228	error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
	229	error("@ WARNING: UNPROTECTED PRIVATE KEY FILE! @");
	230	error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
	231	error("Bad ownership or mode(0%3.3o) for '%s'.",
	232	st.st_mode & 0777, filename);
	233	error("It is recommended that your private key files are NOT accessible by others.");
	234	return 0;
	235	}
a408af76	236	len = lseek(fd, (off_t) 0, SEEK_END);
a408af76	237	lseek(fd, (off_t) 0, SEEK_SET);
5260325f	238
	239	buffer_init(&buffer);
	240	buffer_append_space(&buffer, &cp, len);
	241
a408af76	242	if (read(fd, cp, (size_t) len) != (size_t) len) {
5260325f	243	debug("Read from key file %.200s failed: %.100s", filename,
	244	strerror(errno));
	245	buffer_free(&buffer);
a408af76	246	close(fd);
5260325f	247	return 0;
5260325f	248	}
a408af76	249	close(fd);
5260325f	250
	251	/* Check that it is at least big enought to contain the ID string. */
	252	if (len < strlen(AUTHFILE_ID_STRING) + 1) {
	253	debug("Bad key file %.200s.", filename);
	254	buffer_free(&buffer);
	255	return 0;
	256	}
aa3378df	257	/*
	258	* Make sure it begins with the id string. Consume the id string
	259	* from the buffer.
	260	*/
5260325f	261	for (i = 0; i < (unsigned int) strlen(AUTHFILE_ID_STRING) + 1; i++)
	262	if (buffer_get_char(&buffer) != (unsigned char) AUTHFILE_ID_STRING[i]) {
	263	debug("Bad key file %.200s.", filename);
	264	buffer_free(&buffer);
	265	return 0;
	266	}
	267	/* Read cipher type. */
	268	cipher_type = buffer_get_char(&buffer);
	269	(void) buffer_get_int(&buffer); /* Reserved data. */
	270
	271	/* Read the public key from the buffer. */
	272	buffer_get_int(&buffer);
	273	prv->n = BN_new();
	274	buffer_get_bignum(&buffer, prv->n);
	275	prv->e = BN_new();
	276	buffer_get_bignum(&buffer, prv->e);
	277	if (comment_return)
	278	*comment_return = buffer_get_string(&buffer, NULL);
	279	else
	280	xfree(buffer_get_string(&buffer, NULL));
	281
	282	/* Check that it is a supported cipher. */
8ce64345	283	if (((cipher_mask1() \| SSH_CIPHER_NONE \| SSH_AUTHFILE_CIPHER) &
5260325f	284	(1 << cipher_type)) == 0) {
	285	debug("Unsupported cipher %.100s used in key file %.200s.",
	286	cipher_name(cipher_type), filename);
	287	buffer_free(&buffer);
	288	goto fail;
	289	}
	290	/* Initialize space for decrypted data. */
	291	buffer_init(&decrypted);
	292	buffer_append_space(&decrypted, &cp, buffer_len(&buffer));
	293
	294	/* Rest of the buffer is encrypted. Decrypt it using the passphrase. */
8ce64345	295	cipher_set_key_string(&cipher, cipher_type, passphrase);
5260325f	296	cipher_decrypt(&cipher, (unsigned char *) cp,
	297	(unsigned char *) buffer_ptr(&buffer),
	298	buffer_len(&buffer));
	299
8efc0c15	300	buffer_free(&buffer);
5260325f	301
	302	check1 = buffer_get_char(&decrypted);
	303	check2 = buffer_get_char(&decrypted);
	304	if (check1 != buffer_get_char(&decrypted) \|\|
	305	check2 != buffer_get_char(&decrypted)) {
	306	if (strcmp(passphrase, "") != 0)
	307	debug("Bad passphrase supplied for key file %.200s.", filename);
	308	/* Bad passphrase. */
	309	buffer_free(&decrypted);
	310	fail:
	311	BN_clear_free(prv->n);
	312	BN_clear_free(prv->e);
	313	if (comment_return)
	314	xfree(*comment_return);
	315	return 0;
	316	}
	317	/* Read the rest of the private key. */
	318	prv->d = BN_new();
	319	buffer_get_bignum(&decrypted, prv->d);
	320	prv->iqmp = BN_new();
	321	buffer_get_bignum(&decrypted, prv->iqmp); /* u */
	322	/* in SSL and SSH p and q are exchanged */
	323	prv->q = BN_new();
	324	buffer_get_bignum(&decrypted, prv->q); /* p */
	325	prv->p = BN_new();
	326	buffer_get_bignum(&decrypted, prv->p); /* q */
	327
	328	ctx = BN_CTX_new();
	329	aux = BN_new();
	330
	331	BN_sub(aux, prv->q, BN_value_one());
	332	prv->dmq1 = BN_new();
	333	BN_mod(prv->dmq1, prv->d, aux, ctx);
	334
	335	BN_sub(aux, prv->p, BN_value_one());
	336	prv->dmp1 = BN_new();
	337	BN_mod(prv->dmp1, prv->d, aux, ctx);
	338
	339	BN_clear_free(aux);
	340	BN_CTX_free(ctx);
	341
	342	buffer_free(&decrypted);
	343
	344	return 1;
8efc0c15	345	}