[openssh.git] / key.c

/*
 * Copyright (c) 2000 Markus Friedl.  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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Markus Friedl.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * 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.
 */
/*
 * read_bignum():
 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
 */

#include "includes.h"

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

#include "ssh.h"
#include "xmalloc.h"
#include "key.h"

Key *
key_new(int type)
{
	Key *k;
	RSA *rsa;
	DSA *dsa;
	k = xmalloc(sizeof(*k));
	k->type = type;
	switch (k->type) {
	case KEY_RSA:
		rsa = RSA_new();
		rsa->n = BN_new();
		rsa->e = BN_new();
		k->rsa = rsa;
		break;
	case KEY_DSA:
		dsa = DSA_new();
		dsa->p = BN_new();
		dsa->q = BN_new();
		dsa->g = BN_new();
		dsa->pub_key = BN_new();
		k->dsa = dsa;
		break;
	case KEY_EMPTY:
		k->dsa = NULL;
		k->rsa = NULL;
		break;
	default:
		fatal("key_new: bad key type %d", k->type);
		break;
	}
	return k;
}
void
key_free(Key *k)
{
	switch (k->type) {
	case KEY_RSA:
		if (k->rsa != NULL)
			RSA_free(k->rsa);
		k->rsa = NULL;
		break;
	case KEY_DSA:
		if (k->dsa != NULL)
			DSA_free(k->dsa);
		k->dsa = NULL;
		break;
	default:
		fatal("key_free: bad key type %d", k->type);
		break;
	}
	xfree(k);
}
int
key_equal(Key *a, Key *b)
{
	if (a == NULL || b == NULL || a->type != b->type)
		return 0;
	switch (a->type) {
	case KEY_RSA:
		return a->rsa != NULL && b->rsa != NULL &&
		    BN_cmp(a->rsa->e, b->rsa->e) == 0 &&
		    BN_cmp(a->rsa->n, b->rsa->n) == 0;
		break;
	case KEY_DSA:
		return a->dsa != NULL && b->dsa != NULL &&
		    BN_cmp(a->dsa->p, b->dsa->p) == 0 &&
		    BN_cmp(a->dsa->q, b->dsa->q) == 0 &&
		    BN_cmp(a->dsa->g, b->dsa->g) == 0 &&
		    BN_cmp(a->dsa->pub_key, b->dsa->pub_key) == 0;
		break;
	default:
		fatal("key_free: bad key type %d", a->type);
		break;
	}
	return 0;
}

#define FPRINT "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x"

/*
 * Generate key fingerprint in ascii format.
 * Based on ideas and code from Bjoern Groenvall <bg@sics.se>
 */
char *
key_fingerprint(Key *k)
{
	static char retval[80];
	unsigned char *buf = NULL;
	int len = 0;
	int nlen, elen, plen, qlen, glen, publen;

	switch (k->type) {
	case KEY_RSA:
		nlen = BN_num_bytes(k->rsa->n);
		elen = BN_num_bytes(k->rsa->e);
		len = nlen + elen;
		buf = xmalloc(len);
		BN_bn2bin(k->rsa->n, buf);
		BN_bn2bin(k->rsa->e, buf + nlen);
		break;
	case KEY_DSA:
		plen = BN_num_bytes(k->dsa->p);
		qlen = BN_num_bytes(k->dsa->q);
		glen = BN_num_bytes(k->dsa->g);
		publen = BN_num_bytes(k->dsa->pub_key);
		len = qlen + qlen + glen + publen;
		buf = xmalloc(len);
		BN_bn2bin(k->dsa->p, buf);
		BN_bn2bin(k->dsa->q, buf + plen);
		BN_bn2bin(k->dsa->g, buf + plen + qlen);
		BN_bn2bin(k->dsa->pub_key , buf + plen + qlen + glen);
		break;
	default:
		fatal("key_fingerprint: bad key type %d", k->type);
		break;
	}
	if (buf != NULL) {
		unsigned char d[16];
		EVP_MD_CTX md;
		EVP_DigestInit(&md, EVP_md5());
		EVP_DigestUpdate(&md, buf, len);
		EVP_DigestFinal(&md, d, NULL);
		snprintf(retval, sizeof(retval), FPRINT,
		    d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7],
		    d[8], d[9], d[10], d[11], d[12], d[13], d[14], d[15]);
		memset(buf, 0, len);
		xfree(buf);
	}
	return retval;
}

/*
 * Reads a multiple-precision integer in decimal from the buffer, and advances
 * the pointer.  The integer must already be initialized.  This function is
 * permitted to modify the buffer.  This leaves *cpp to point just beyond the
 * last processed (and maybe modified) character.  Note that this may modify
 * the buffer containing the number.
 */
int
read_bignum(char **cpp, BIGNUM * value)
{
	char *cp = *cpp;
	int old;

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

	/* Check that it begins with a decimal digit. */
	if (*cp < '0' || *cp > '9')
		return 0;

	/* Save starting position. */
	*cpp = cp;

	/* Move forward until all decimal digits skipped. */
	for (; *cp >= '0' && *cp <= '9'; cp++)
		;

	/* Save the old terminating character, and replace it by \0. */
	old = *cp;
	*cp = 0;

	/* Parse the number. */
	if (BN_dec2bn(&value, *cpp) == 0)
		return 0;

	/* Restore old terminating character. */
	*cp = old;

	/* Move beyond the number and return success. */
	*cpp = cp;
	return 1;
}
int
write_bignum(FILE *f, BIGNUM *num)
{
	char *buf = BN_bn2dec(num);
	if (buf == NULL) {
		error("write_bignum: BN_bn2dec() failed");
		return 0;
	}
	fprintf(f, " %s", buf);
	free(buf);
	return 1;
}
int
key_read(Key *ret, unsigned int bits, char **cpp)
{
	switch(ret->type) {
	case KEY_RSA:
		if (bits == 0)
			return 0;
		/* Get public exponent, public modulus. */
		if (!read_bignum(cpp, ret->rsa->e))
			return 0;
		if (!read_bignum(cpp, ret->rsa->n))
			return 0;
		break;
	case KEY_DSA:
		if (bits != 0)
			return 0;
		if (!read_bignum(cpp, ret->dsa->p))
			return 0;
		if (!read_bignum(cpp, ret->dsa->q))
			return 0;
		if (!read_bignum(cpp, ret->dsa->g))
			return 0;
		if (!read_bignum(cpp, ret->dsa->pub_key))
			return 0;
		break;
	default:
		fatal("bad key type: %d", ret->type);
		break;
	}
	return 1;
}
int
key_write(Key *key, FILE *f)
{
	int success = 0;
	unsigned int bits = 0;

	if (key->type == KEY_RSA && key->rsa != NULL) {
		/* size of modulus 'n' */
		bits = BN_num_bits(key->rsa->n);
		fprintf(f, "%u", bits);
		if (write_bignum(f, key->rsa->e) &&
		    write_bignum(f, key->rsa->n)) {
			success = 1;
		} else {
			error("key_write: failed for RSA key");
		}
	} else if (key->type == KEY_DSA && key->dsa != NULL) {
		/* bits == 0 means DSA key */
		bits = 0;
		fprintf(f, "%u", bits);
		if (write_bignum(f, key->dsa->p) &&
		    write_bignum(f, key->dsa->q) &&
		    write_bignum(f, key->dsa->g) &&
		    write_bignum(f, key->dsa->pub_key)) {
			success = 1;
		} else {
			error("key_write: failed for DSA key");
		}
	}
	return success;
}
Commit	Line	Data
4fe2af09	1	/*
	2	* Copyright (c) 2000 Markus Friedl. All rights reserved.
	3	*
	4	* Redistribution and use in source and binary forms, with or without
	5	* modification, are permitted provided that the following conditions
	6	* are met:
	7	* 1. Redistributions of source code must retain the above copyright
	8	* notice, this list of conditions and the following disclaimer.
	9	* 2. Redistributions in binary form must reproduce the above copyright
	10	* notice, this list of conditions and the following disclaimer in the
	11	* documentation and/or other materials provided with the distribution.
	12	* 3. All advertising materials mentioning features or use of this software
	13	* must display the following acknowledgement:
	14	* This product includes software developed by Markus Friedl.
	15	* 4. The name of the author may not be used to endorse or promote products
	16	* derived from this software without specific prior written permission.
	17	*
	18	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
	19	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	20	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	21	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	22	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	23	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	24	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	25	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	26	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	27	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	28	*/
	29	/*
	30	* read_bignum():
	31	* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
	32	*/
	33
	34	#include "includes.h"
	35
	36	#ifdef HAVE_OPENSSL
	37	#include <openssl/bn.h>
	38	#include <openssl/rsa.h>
	39	#include <openssl/dsa.h>
	40	#include <openssl/evp.h>
	41	#endif
	42	#ifdef HAVE_SSL
	43	#include <ssl/bn.h>
	44	#include <ssl/rsa.h>
	45	#include <ssl/dsa.h>
	46	#include <ssl/evp.h>
	47	#endif
	48
	49	#include "ssh.h"
	50	#include "xmalloc.h"
	51	#include "key.h"
	52
	53	Key *
	54	key_new(int type)
	55	{
	56	Key *k;
	57	RSA *rsa;
	58	DSA *dsa;
	59	k = xmalloc(sizeof(*k));
	60	k->type = type;
	61	switch (k->type) {
	62	case KEY_RSA:
	63	rsa = RSA_new();
	64	rsa->n = BN_new();
65	rsa->e = BN_new();
66	k->rsa = rsa;
67	break;
68	case KEY_DSA:
69	dsa = DSA_new();
70	dsa->p = BN_new();
71	dsa->q = BN_new();
72	dsa->g = BN_new();
73	dsa->pub_key = BN_new();
74	k->dsa = dsa;
75	break;
76	case KEY_EMPTY:
77	k->dsa = NULL;
78	k->rsa = NULL;
79	break;
80	default:
81	fatal("key_new: bad key type %d", k->type);
82	break;
83	}
84	return k;
85	}
86	void
87	key_free(Key *k)
88	{
89	switch (k->type) {
90	case KEY_RSA:
91	if (k->rsa != NULL)
92	RSA_free(k->rsa);
93	k->rsa = NULL;
94	break;
95	case KEY_DSA:
96	if (k->dsa != NULL)
97	DSA_free(k->dsa);
98	k->dsa = NULL;
99	break;
100	default:
101	fatal("key_free: bad key type %d", k->type);
102	break;
103	}
104	xfree(k);
105	}
106	int
107	key_equal(Key a, Key b)
108	{
109	if (a == NULL \|\| b == NULL \|\| a->type != b->type)
110	return 0;
111	switch (a->type) {
112	case KEY_RSA:
113	return a->rsa != NULL && b->rsa != NULL &&
114	BN_cmp(a->rsa->e, b->rsa->e) == 0 &&
115	BN_cmp(a->rsa->n, b->rsa->n) == 0;
116	break;
117	case KEY_DSA:
118	return a->dsa != NULL && b->dsa != NULL &&
119	BN_cmp(a->dsa->p, b->dsa->p) == 0 &&
120	BN_cmp(a->dsa->q, b->dsa->q) == 0 &&
121	BN_cmp(a->dsa->g, b->dsa->g) == 0 &&
122	BN_cmp(a->dsa->pub_key, b->dsa->pub_key) == 0;
123	break;
124	default:
125	fatal("key_free: bad key type %d", a->type);
126	break;
127	}
128	return 0;
129	}
130
131	#define FPRINT "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x"
132
133	/*
134	* Generate key fingerprint in ascii format.
135	* Based on ideas and code from Bjoern Groenvall <bg@sics.se>
136	*/
137	char *
138	key_fingerprint(Key *k)
139	{
140	static char retval[80];
141	unsigned char *buf = NULL;
142	int len = 0;
143	int nlen, elen, plen, qlen, glen, publen;
144
145	switch (k->type) {
146	case KEY_RSA:
147	nlen = BN_num_bytes(k->rsa->n);
148	elen = BN_num_bytes(k->rsa->e);
149	len = nlen + elen;
150	buf = xmalloc(len);
151	BN_bn2bin(k->rsa->n, buf);
152	BN_bn2bin(k->rsa->e, buf + nlen);
153	break;
154	case KEY_DSA:
155	plen = BN_num_bytes(k->dsa->p);
156	qlen = BN_num_bytes(k->dsa->q);
157	glen = BN_num_bytes(k->dsa->g);
158	publen = BN_num_bytes(k->dsa->pub_key);
159	len = qlen + qlen + glen + publen;
160	buf = xmalloc(len);
161	BN_bn2bin(k->dsa->p, buf);
162	BN_bn2bin(k->dsa->q, buf + plen);
163	BN_bn2bin(k->dsa->g, buf + plen + qlen);
164	BN_bn2bin(k->dsa->pub_key , buf + plen + qlen + glen);
165	break;
166	default:
167	fatal("key_fingerprint: bad key type %d", k->type);
168	break;
169	}
170	if (buf != NULL) {
171	unsigned char d[16];
172	EVP_MD_CTX md;
173	EVP_DigestInit(&md, EVP_md5());
174	EVP_DigestUpdate(&md, buf, len);
175	EVP_DigestFinal(&md, d, NULL);
176	snprintf(retval, sizeof(retval), FPRINT,
177	d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7],
178	d[8], d[9], d[10], d[11], d[12], d[13], d[14], d[15]);
179	memset(buf, 0, len);
180	xfree(buf);
181	}
182	return retval;
183	}
184
185	/*
186	* Reads a multiple-precision integer in decimal from the buffer, and advances
187	* the pointer. The integer must already be initialized. This function is
188	* permitted to modify the buffer. This leaves *cpp to point just beyond the
189	* last processed (and maybe modified) character. Note that this may modify
190	* the buffer containing the number.
191	*/
192	int
193	read_bignum(char *cpp, BIGNUM value)
194	{
195	char cp = cpp;
196	int old;
197
198	/* Skip any leading whitespace. */
199	for (; cp == ' ' \|\| cp == '\t'; cp++)
200	;
201
202	/* Check that it begins with a decimal digit. */
203	if (cp < '0' \|\| cp > '9')
204	return 0;
205
206	/* Save starting position. */
207	*cpp = cp;
208
209	/* Move forward until all decimal digits skipped. */
210	for (; cp >= '0' && cp <= '9'; cp++)
211	;
212
213	/* Save the old terminating character, and replace it by \0. */
214	old = *cp;
215	*cp = 0;
216
217	/* Parse the number. */
218	if (BN_dec2bn(&value, *cpp) == 0)
219	return 0;
220
221	/* Restore old terminating character. */
222	*cp = old;
223
224	/* Move beyond the number and return success. */
225	*cpp = cp;
226	return 1;
227	}
228	int
229	write_bignum(FILE f, BIGNUM num)
230	{
231	char *buf = BN_bn2dec(num);
232	if (buf == NULL) {
233	error("write_bignum: BN_bn2dec() failed");
234	return 0;
235	}
236	fprintf(f, " %s", buf);
237	free(buf);
238	return 1;
239	}
240	int
241	key_read(Key ret, unsigned int bits, char *cpp)
242	{
243	switch(ret->type) {
244	case KEY_RSA:
245	if (bits == 0)
246	return 0;
247	/* Get public exponent, public modulus. */
248	if (!read_bignum(cpp, ret->rsa->e))
249	return 0;
250	if (!read_bignum(cpp, ret->rsa->n))
251	return 0;
252	break;
253	case KEY_DSA:
254	if (bits != 0)
255	return 0;
256	if (!read_bignum(cpp, ret->dsa->p))
257	return 0;
258	if (!read_bignum(cpp, ret->dsa->q))
259	return 0;
260	if (!read_bignum(cpp, ret->dsa->g))
261	return 0;
262	if (!read_bignum(cpp, ret->dsa->pub_key))
263	return 0;
264	break;
265	default:
266	fatal("bad key type: %d", ret->type);
267	break;
268	}
269	return 1;
270	}
271	int
272	key_write(Key key, FILE f)
273	{
274	int success = 0;
275	unsigned int bits = 0;
276
277	if (key->type == KEY_RSA && key->rsa != NULL) {
278	/* size of modulus 'n' */
279	bits = BN_num_bits(key->rsa->n);
280	fprintf(f, "%u", bits);
281	if (write_bignum(f, key->rsa->e) &&
282	write_bignum(f, key->rsa->n)) {
283	success = 1;
284	} else {
285	error("key_write: failed for RSA key");
286	}
287	} else if (key->type == KEY_DSA && key->dsa != NULL) {
288	/* bits == 0 means DSA key */
289	bits = 0;
290	fprintf(f, "%u", bits);
291	if (write_bignum(f, key->dsa->p) &&
292	write_bignum(f, key->dsa->q) &&
293	write_bignum(f, key->dsa->g) &&
294	write_bignum(f, key->dsa->pub_key)) {
295	success = 1;
296	} else {
297	error("key_write: failed for DSA key");
298	}
299	}
300	return success;
301	}