[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("$Id$");

#ifdef HAVE_OPENSSL
#include <openssl/bn.h>
#endif
#ifdef HAVE_SSL
#include <ssl/bn.h>
#endif

#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, 1);
	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_mask() | 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, 0);
	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	/*
5260325f	2	*
	3	* authfile.c
	4	*
	5	* Author: Tatu Ylonen <ylo@cs.hut.fi>
	6	*
	7	* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
	8	* All rights reserved
	9	*
	10	* Created: Mon Mar 27 03:52:05 1995 ylo
	11	*
	12	* This file contains functions for reading and writing identity files, and
	13	* for reading the passphrase from the user.
	14	*
	15	*/
8efc0c15	16
	17	#include "includes.h"
	18	RCSID("$Id$");
	19
5881cd60	20	#ifdef HAVE_OPENSSL
8efc0c15	21	#include <openssl/bn.h>
5881cd60	22	#endif
	23	#ifdef HAVE_SSL
	24	#include <ssl/bn.h>
	25	#endif
	26
8efc0c15	27	#include "xmalloc.h"
	28	#include "buffer.h"
	29	#include "bufaux.h"
	30	#include "cipher.h"
	31	#include "ssh.h"
	32
	33	/* Version identification string for identity files. */
	34	#define AUTHFILE_ID_STRING "SSH PRIVATE KEY FILE FORMAT 1.1\n"
	35
aa3378df	36	/*
	37	* Saves the authentication (private) key in a file, encrypting it with
	38	* passphrase. The identification of the file (lowest 64 bits of n) will
	39	* precede the key to provide identification of the key without needing a
	40	* passphrase.
	41	*/
8efc0c15	42
	43	int
	44	save_private_key(const char filename, const char passphrase,
	45	RSA key, const char comment)
	46	{
5260325f	47	Buffer buffer, encrypted;
5260325f	48	char buf[100], *cp;
a408af76	49	int fd, i;
5260325f	50	CipherContext cipher;
	51	int cipher_type;
	52	u_int32_t rand;
	53
aa3378df	54	/*
	55	* If the passphrase is empty, use SSH_CIPHER_NONE to ease converting
	56	* to another cipher; otherwise use SSH_AUTHFILE_CIPHER.
	57	*/
5260325f	58	if (strcmp(passphrase, "") == 0)
	59	cipher_type = SSH_CIPHER_NONE;
	60	else
	61	cipher_type = SSH_AUTHFILE_CIPHER;
	62
	63	/* This buffer is used to built the secret part of the private key. */
	64	buffer_init(&buffer);
	65
	66	/* Put checkbytes for checking passphrase validity. */
	67	rand = arc4random();
	68	buf[0] = rand & 0xff;
	69	buf[1] = (rand >> 8) & 0xff;
	70	buf[2] = buf[0];
	71	buf[3] = buf[1];
	72	buffer_append(&buffer, buf, 4);
	73
aa3378df	74	/*
	75	* Store the private key (n and e will not be stored because they
	76	* will be stored in plain text, and storing them also in encrypted
	77	* format would just give known plaintext).
	78	*/
5260325f	79	buffer_put_bignum(&buffer, key->d);
	80	buffer_put_bignum(&buffer, key->iqmp);
	81	buffer_put_bignum(&buffer, key->q); /* reverse from SSL p */
	82	buffer_put_bignum(&buffer, key->p); /* reverse from SSL q */
	83
	84	/* Pad the part to be encrypted until its size is a multiple of 8. */
	85	while (buffer_len(&buffer) % 8 != 0)
	86	buffer_put_char(&buffer, 0);
	87
	88	/* This buffer will be used to contain the data in the file. */
	89	buffer_init(&encrypted);
	90
	91	/* First store keyfile id string. */
	92	cp = AUTHFILE_ID_STRING;
	93	for (i = 0; cp[i]; i++)
	94	buffer_put_char(&encrypted, cp[i]);
	95	buffer_put_char(&encrypted, 0);
	96
	97	/* Store cipher type. */
	98	buffer_put_char(&encrypted, cipher_type);
	99	buffer_put_int(&encrypted, 0); /* For future extension */
	100
	101	/* Store public key. This will be in plain text. */
	102	buffer_put_int(&encrypted, BN_num_bits(key->n));
	103	buffer_put_bignum(&encrypted, key->n);
	104	buffer_put_bignum(&encrypted, key->e);
	105	buffer_put_string(&encrypted, comment, strlen(comment));
	106
	107	/* Allocate space for the private part of the key in the buffer. */
	108	buffer_append_space(&encrypted, &cp, buffer_len(&buffer));
	109
	110	cipher_set_key_string(&cipher, cipher_type, passphrase, 1);
	111	cipher_encrypt(&cipher, (unsigned char *) cp,
	112	(unsigned char *) buffer_ptr(&buffer),
	113	buffer_len(&buffer));
	114	memset(&cipher, 0, sizeof(cipher));
	115
	116	/* Destroy temporary data. */
	117	memset(buf, 0, sizeof(buf));
	118	buffer_free(&buffer);
	119
a408af76	120	fd = open(filename, O_WRONLY \| O_CREAT \| O_TRUNC, 0600);
a408af76	121	if (fd < 0)
5260325f	122	return 0;
a408af76	123	if (write(fd, buffer_ptr(&encrypted), buffer_len(&encrypted)) !=
5260325f	124	buffer_len(&encrypted)) {
	125	debug("Write to key file %.200s failed: %.100s", filename,
	126	strerror(errno));
	127	buffer_free(&encrypted);
a408af76	128	close(fd);
5260325f	129	remove(filename);
	130	return 0;
	131	}
a408af76	132	close(fd);
5260325f	133	buffer_free(&encrypted);
5260325f	134	return 1;
8efc0c15	135	}
8efc0c15	136
aa3378df	137	/*
	138	* Loads the public part of the key file. Returns 0 if an error was
	139	* encountered (the file does not exist or is not readable), and non-zero
	140	* otherwise.
	141	*/
8efc0c15	142
8efc0c15	143	int
5260325f	144	load_public_key(const char filename, RSA pub,
8efc0c15	145	char **comment_return)
8efc0c15	146	{
a408af76	147	int fd, i;
5260325f	148	off_t len;
	149	Buffer buffer;
	150	char *cp;
	151
a408af76	152	fd = open(filename, O_RDONLY);
a408af76	153	if (fd < 0)
5260325f	154	return 0;
a408af76	155	len = lseek(fd, (off_t) 0, SEEK_END);
a408af76	156	lseek(fd, (off_t) 0, SEEK_SET);
5260325f	157
	158	buffer_init(&buffer);
	159	buffer_append_space(&buffer, &cp, len);
	160
a408af76	161	if (read(fd, cp, (size_t) len) != (size_t) len) {
5260325f	162	debug("Read from key file %.200s failed: %.100s", filename,
	163	strerror(errno));
	164	buffer_free(&buffer);
a408af76	165	close(fd);
5260325f	166	return 0;
5260325f	167	}
a408af76	168	close(fd);
5260325f	169
	170	/* Check that it is at least big enought to contain the ID string. */
	171	if (len < strlen(AUTHFILE_ID_STRING) + 1) {
	172	debug("Bad key file %.200s.", filename);
	173	buffer_free(&buffer);
	174	return 0;
	175	}
aa3378df	176	/*
	177	* Make sure it begins with the id string. Consume the id string
	178	* from the buffer.
	179	*/
5260325f	180	for (i = 0; i < (unsigned int) strlen(AUTHFILE_ID_STRING) + 1; i++)
a408af76	181	if (buffer_get_char(&buffer) != (u_char) AUTHFILE_ID_STRING[i]) {
5260325f	182	debug("Bad key file %.200s.", filename);
	183	buffer_free(&buffer);
	184	return 0;
	185	}
	186	/* Skip cipher type and reserved data. */
	187	(void) buffer_get_char(&buffer); /* cipher type */
	188	(void) buffer_get_int(&buffer); /* reserved */
	189
	190	/* Read the public key from the buffer. */
	191	buffer_get_int(&buffer);
	192	pub->n = BN_new();
	193	buffer_get_bignum(&buffer, pub->n);
	194	pub->e = BN_new();
	195	buffer_get_bignum(&buffer, pub->e);
	196	if (comment_return)
	197	*comment_return = buffer_get_string(&buffer, NULL);
	198	/* The encrypted private part is not parsed by this function. */
	199
8efc0c15	200	buffer_free(&buffer);
5260325f	201
5260325f	202	return 1;
8efc0c15	203	}
8efc0c15	204
aa3378df	205	/*
	206	* Loads the private key from the file. Returns 0 if an error is encountered
	207	* (file does not exist or is not readable, or passphrase is bad). This
	208	* initializes the private key.
	209	* Assumes we are called under uid of the owner of the file.
	210	*/
8efc0c15	211
	212	int
	213	load_private_key(const char filename, const char passphrase,
5260325f	214	RSA * prv, char **comment_return)
8efc0c15	215	{
a408af76	216	int fd, i, check1, check2, cipher_type;
5260325f	217	off_t len;
	218	Buffer buffer, decrypted;
	219	char *cp;
	220	CipherContext cipher;
	221	BN_CTX *ctx;
	222	BIGNUM *aux;
	223	struct stat st;
	224
a408af76	225	fd = open(filename, O_RDONLY);
a408af76	226	if (fd < 0)
5260325f	227	return 0;
5260325f	228
aa3378df	229	/* check owner and modes */
a408af76	230	if (fstat(fd, &st) < 0 \|\|
81eef326	231	(st.st_uid != 0 && getuid() != 0 && st.st_uid != getuid()) \|\|
5260325f	232	(st.st_mode & 077) != 0) {
a408af76	233	close(fd);
5260325f	234	error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
	235	error("@ WARNING: UNPROTECTED PRIVATE KEY FILE! @");
	236	error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
	237	error("Bad ownership or mode(0%3.3o) for '%s'.",
	238	st.st_mode & 0777, filename);
	239	error("It is recommended that your private key files are NOT accessible by others.");
	240	return 0;
	241	}
a408af76	242	len = lseek(fd, (off_t) 0, SEEK_END);
a408af76	243	lseek(fd, (off_t) 0, SEEK_SET);
5260325f	244
	245	buffer_init(&buffer);
	246	buffer_append_space(&buffer, &cp, len);
	247
a408af76	248	if (read(fd, cp, (size_t) len) != (size_t) len) {
5260325f	249	debug("Read from key file %.200s failed: %.100s", filename,
	250	strerror(errno));
	251	buffer_free(&buffer);
a408af76	252	close(fd);
5260325f	253	return 0;
5260325f	254	}
a408af76	255	close(fd);
5260325f	256
	257	/* Check that it is at least big enought to contain the ID string. */
	258	if (len < strlen(AUTHFILE_ID_STRING) + 1) {
	259	debug("Bad key file %.200s.", filename);
	260	buffer_free(&buffer);
	261	return 0;
	262	}
aa3378df	263	/*
	264	* Make sure it begins with the id string. Consume the id string
	265	* from the buffer.
	266	*/
5260325f	267	for (i = 0; i < (unsigned int) strlen(AUTHFILE_ID_STRING) + 1; i++)
	268	if (buffer_get_char(&buffer) != (unsigned char) AUTHFILE_ID_STRING[i]) {
	269	debug("Bad key file %.200s.", filename);
	270	buffer_free(&buffer);
	271	return 0;
	272	}
	273	/* Read cipher type. */
	274	cipher_type = buffer_get_char(&buffer);
	275	(void) buffer_get_int(&buffer); /* Reserved data. */
	276
	277	/* Read the public key from the buffer. */
	278	buffer_get_int(&buffer);
	279	prv->n = BN_new();
	280	buffer_get_bignum(&buffer, prv->n);
	281	prv->e = BN_new();
	282	buffer_get_bignum(&buffer, prv->e);
	283	if (comment_return)
	284	*comment_return = buffer_get_string(&buffer, NULL);
	285	else
	286	xfree(buffer_get_string(&buffer, NULL));
	287
	288	/* Check that it is a supported cipher. */
	289	if (((cipher_mask() \| SSH_CIPHER_NONE \| SSH_AUTHFILE_CIPHER) &
	290	(1 << cipher_type)) == 0) {
	291	debug("Unsupported cipher %.100s used in key file %.200s.",
	292	cipher_name(cipher_type), filename);
	293	buffer_free(&buffer);
	294	goto fail;
	295	}
	296	/* Initialize space for decrypted data. */
	297	buffer_init(&decrypted);
	298	buffer_append_space(&decrypted, &cp, buffer_len(&buffer));
	299
	300	/* Rest of the buffer is encrypted. Decrypt it using the passphrase. */
	301	cipher_set_key_string(&cipher, cipher_type, passphrase, 0);
	302	cipher_decrypt(&cipher, (unsigned char *) cp,
	303	(unsigned char *) buffer_ptr(&buffer),
	304	buffer_len(&buffer));
	305
8efc0c15	306	buffer_free(&buffer);
5260325f	307
	308	check1 = buffer_get_char(&decrypted);
	309	check2 = buffer_get_char(&decrypted);
	310	if (check1 != buffer_get_char(&decrypted) \|\|
	311	check2 != buffer_get_char(&decrypted)) {
	312	if (strcmp(passphrase, "") != 0)
	313	debug("Bad passphrase supplied for key file %.200s.", filename);
	314	/* Bad passphrase. */
	315	buffer_free(&decrypted);
	316	fail:
	317	BN_clear_free(prv->n);
	318	BN_clear_free(prv->e);
	319	if (comment_return)
	320	xfree(*comment_return);
	321	return 0;
	322	}
	323	/* Read the rest of the private key. */
	324	prv->d = BN_new();
	325	buffer_get_bignum(&decrypted, prv->d);
	326	prv->iqmp = BN_new();
	327	buffer_get_bignum(&decrypted, prv->iqmp); /* u */
	328	/* in SSL and SSH p and q are exchanged */
	329	prv->q = BN_new();
	330	buffer_get_bignum(&decrypted, prv->q); /* p */
	331	prv->p = BN_new();
	332	buffer_get_bignum(&decrypted, prv->p); /* q */
	333
	334	ctx = BN_CTX_new();
	335	aux = BN_new();
	336
	337	BN_sub(aux, prv->q, BN_value_one());
	338	prv->dmq1 = BN_new();
	339	BN_mod(prv->dmq1, prv->d, aux, ctx);
	340
	341	BN_sub(aux, prv->p, BN_value_one());
	342	prv->dmp1 = BN_new();
	343	BN_mod(prv->dmp1, prv->d, aux, ctx);
	344
	345	BN_clear_free(aux);
	346	BN_CTX_free(ctx);
	347
	348	buffer_free(&decrypted);
	349
	350	return 1;
8efc0c15	351	}