[openssh.git] / key.c

/*
 * read_bignum():
 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
 *
 * 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) 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.
 *
 * 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"
RCSID("$OpenBSD: key.c,v 1.17 2001/02/04 15:32:24 stevesk Exp $");

#include <openssl/evp.h>

#include "xmalloc.h"
#include "key.h"
#include "rsa.h"
#include "ssh-dss.h"
#include "ssh-rsa.h"
#include "uuencode.h"
#include "buffer.h"
#include "bufaux.h"
#include "log.h"

Key *
key_new(int type)
{
	Key *k;
	RSA *rsa;
	DSA *dsa;
	k = xmalloc(sizeof(*k));
	k->type = type;
	k->dsa = NULL;
	k->rsa = NULL;
	switch (k->type) {
	case KEY_RSA1:
	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_UNSPEC:
		break;
	default:
		fatal("key_new: bad key type %d", k->type);
		break;
	}
	return k;
}
Key *
key_new_private(int type)
{
	Key *k = key_new(type);
	switch (k->type) {
	case KEY_RSA1:
	case KEY_RSA:
		k->rsa->d = BN_new();
		k->rsa->iqmp = BN_new();
		k->rsa->q = BN_new();
		k->rsa->p = BN_new();
		k->rsa->dmq1 = BN_new();
		k->rsa->dmp1 = BN_new();
		break;
	case KEY_DSA:
		k->dsa->priv_key = BN_new();
		break;
	case KEY_UNSPEC:
		break;
	default:
		break;
	}
	return k;
}
void
key_free(Key *k)
{
	switch (k->type) {
	case KEY_RSA1:
	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;
	case KEY_UNSPEC:
		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_RSA1:
	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_equal: bad key type %d", a->type);
		break;
	}
	return 0;
}

/*
 * 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[(EVP_MAX_MD_SIZE+1)*3];
	u_char *blob = NULL;
	int len = 0;
	int nlen, elen;

	retval[0] = '\0';
	switch (k->type) {
	case KEY_RSA1:
		nlen = BN_num_bytes(k->rsa->n);
		elen = BN_num_bytes(k->rsa->e);
		len = nlen + elen;
		blob = xmalloc(len);
		BN_bn2bin(k->rsa->n, blob);
		BN_bn2bin(k->rsa->e, blob + nlen);
		break;
	case KEY_DSA:
	case KEY_RSA:
		key_to_blob(k, &blob, &len);
		break;
	case KEY_UNSPEC:
		return retval;
		break;
	default:
		fatal("key_fingerprint: bad key type %d", k->type);
		break;
	}
	if (blob != NULL) {
		int i;
		u_char digest[EVP_MAX_MD_SIZE];
		EVP_MD *md = EVP_md5();
		EVP_MD_CTX ctx;
		EVP_DigestInit(&ctx, md);
		EVP_DigestUpdate(&ctx, blob, len);
		EVP_DigestFinal(&ctx, digest, NULL);
		for(i = 0; i < md->md_size; i++) {
			char hex[4];
			snprintf(hex, sizeof(hex), "%02x:", digest[i]);
			strlcat(retval, hex, sizeof(retval));
		}
		retval[strlen(retval) - 1] = '\0';
		memset(blob, 0, len);
		xfree(blob);
	}
	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);
	xfree(buf);
	return 1;
}

/* returns 1 ok, -1 error, 0 type mismatch */
int
key_read(Key *ret, char **cpp)
{
	Key *k;
	int success = -1;
	char *cp, *space;
	int len, n, type;
	u_int bits;
	u_char *blob;

	cp = *cpp;

	switch(ret->type) {
	case KEY_RSA1:
		/* Get number of bits. */
		if (*cp < '0' || *cp > '9')
			return -1;	/* Bad bit count... */
		for (bits = 0; *cp >= '0' && *cp <= '9'; cp++)
			bits = 10 * bits + *cp - '0';
		if (bits == 0)
			return -1;
		*cpp = cp;
		/* Get public exponent, public modulus. */
		if (!read_bignum(cpp, ret->rsa->e))
			return -1;
		if (!read_bignum(cpp, ret->rsa->n))
			return -1;
		success = 1;
		break;
	case KEY_UNSPEC:
	case KEY_RSA:
	case KEY_DSA:
		space = strchr(cp, ' ');
		if (space == NULL) {
			debug3("key_read: no space");
			return -1;
		}
		*space = '\0';
		type = key_type_from_name(cp);
		*space = ' ';
		if (type == KEY_UNSPEC) {
			debug3("key_read: no key found");
			return -1;
		}
		cp = space+1;
		if (*cp == '\0') {
			debug3("key_read: short string");
			return -1;
		}
		if (ret->type == KEY_UNSPEC) {
			ret->type = type;
		} else if (ret->type != type) {
			/* is a key, but different type */
			debug3("key_read: type mismatch");
			return 0;
		}
		len = 2*strlen(cp);
		blob = xmalloc(len);
		n = uudecode(cp, blob, len);
		if (n < 0) {
			error("key_read: uudecode %s failed", cp);
			return -1;
		}
		k = key_from_blob(blob, n);
		if (k == NULL) {
			error("key_read: key_from_blob %s failed", cp);
			return -1;
		}
		xfree(blob);
		if (k->type != type) {
			error("key_read: type mismatch: encoding error");
			key_free(k);
			return -1;
		}
/*XXXX*/
		if (ret->type == KEY_RSA) {
			if (ret->rsa != NULL)
				RSA_free(ret->rsa);
			ret->rsa = k->rsa;
			k->rsa = NULL;
			success = 1;
#ifdef DEBUG_PK
			RSA_print_fp(stderr, ret->rsa, 8);
#endif
		} else {
			if (ret->dsa != NULL)
				DSA_free(ret->dsa);
			ret->dsa = k->dsa;
			k->dsa = NULL;
			success = 1;
#ifdef DEBUG_PK
			DSA_print_fp(stderr, ret->dsa, 8);
#endif
		}
/*XXXX*/
		if (success != 1)
			break;
		key_free(k);
		/* advance cp: skip whitespace and data */
		while (*cp == ' ' || *cp == '\t')
			cp++;
		while (*cp != '\0' && *cp != ' ' && *cp != '\t')
			cp++;
		*cpp = cp;
		break;
	default:
		fatal("key_read: bad key type: %d", ret->type);
		break;
	}
	return success;
}
int
key_write(Key *key, FILE *f)
{
	int success = 0;
	u_int bits = 0;

	if (key->type == KEY_RSA1 && 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) ||
	    (key->type == KEY_RSA && key->rsa != NULL)) {
		int len, n;
		u_char *blob, *uu;
		key_to_blob(key, &blob, &len);
		uu = xmalloc(2*len);
		n = uuencode(blob, len, uu, 2*len);
		if (n > 0) {
			fprintf(f, "%s %s", key_ssh_name(key), uu);
			success = 1;
		}
		xfree(blob);
		xfree(uu);
	}
	return success;
}
char *
key_type(Key *k)
{
	switch (k->type) {
	case KEY_RSA1:
		return "RSA1";
		break;
	case KEY_RSA:
		return "RSA";
		break;
	case KEY_DSA:
		return "DSA";
		break;
	}
	return "unknown";
}
char *
key_ssh_name(Key *k)
{
	switch (k->type) {
	case KEY_RSA:
		return "ssh-rsa";
		break;
	case KEY_DSA:
		return "ssh-dss";
		break;
	}
	return "ssh-unknown";
}
u_int
key_size(Key *k){
	switch (k->type) {
	case KEY_RSA1:
	case KEY_RSA:
		return BN_num_bits(k->rsa->n);
		break;
	case KEY_DSA:
		return BN_num_bits(k->dsa->p);
		break;
	}
	return 0;
}

RSA *
rsa_generate_private_key(u_int bits)
{
	RSA *private;
	private = RSA_generate_key(bits, 35, NULL, NULL);
	if (private == NULL)
		fatal("rsa_generate_private_key: key generation failed.");
	return private;
}

DSA*
dsa_generate_private_key(u_int bits)
{
	DSA *private = DSA_generate_parameters(bits, NULL, 0, NULL, NULL, NULL, NULL);
	if (private == NULL)
		fatal("dsa_generate_private_key: DSA_generate_parameters failed");
	if (!DSA_generate_key(private))
		fatal("dsa_generate_private_key: DSA_generate_key failed.");
	if (private == NULL)
		fatal("dsa_generate_private_key: NULL.");
	return private;
}

Key *
key_generate(int type, u_int bits)
{
	Key *k = key_new(KEY_UNSPEC);
	switch (type) {
	case KEY_DSA:
		k->dsa = dsa_generate_private_key(bits);
		break;
	case KEY_RSA:
	case KEY_RSA1:
		k->rsa = rsa_generate_private_key(bits);
		break;
	default:
		fatal("key_generate: unknown type %d", type);
	}
	k->type = type;
	return k;
}

Key *
key_from_private(Key *k)
{
	Key *n = NULL;
	switch (k->type) {
	case KEY_DSA:
		n = key_new(k->type);
		BN_copy(n->dsa->p, k->dsa->p);
		BN_copy(n->dsa->q, k->dsa->q);
		BN_copy(n->dsa->g, k->dsa->g);
		BN_copy(n->dsa->pub_key, k->dsa->pub_key);
		break;
	case KEY_RSA:
	case KEY_RSA1:
		n = key_new(k->type);
		BN_copy(n->rsa->n, k->rsa->n);
		BN_copy(n->rsa->e, k->rsa->e);
		break;
	default:
		fatal("key_from_private: unknown type %d", k->type);
		break;
	}
	return n;
}

int
key_type_from_name(char *name)
{
	if (strcmp(name, "rsa1") == 0){
		return KEY_RSA1;
	} else if (strcmp(name, "rsa") == 0){
		return KEY_RSA;
	} else if (strcmp(name, "dsa") == 0){
		return KEY_DSA;
	} else if (strcmp(name, "ssh-rsa") == 0){
		return KEY_RSA;
	} else if (strcmp(name, "ssh-dss") == 0){
		return KEY_DSA;
	}
	debug("key_type_from_name: unknown key type '%s'", name);
	return KEY_UNSPEC;
}

Key *
key_from_blob(char *blob, int blen)
{
	Buffer b;
	char *ktype;
	int rlen, type;
	Key *key = NULL;

#ifdef DEBUG_PK
	dump_base64(stderr, blob, blen);
#endif
	buffer_init(&b);
	buffer_append(&b, blob, blen);
	ktype = buffer_get_string(&b, NULL);
	type = key_type_from_name(ktype);

	switch(type){
	case KEY_RSA:
		key = key_new(type);
		buffer_get_bignum2(&b, key->rsa->e);
		buffer_get_bignum2(&b, key->rsa->n);
#ifdef DEBUG_PK
		RSA_print_fp(stderr, key->rsa, 8);
#endif
		break;
	case KEY_DSA:
		key = key_new(type);
		buffer_get_bignum2(&b, key->dsa->p);
		buffer_get_bignum2(&b, key->dsa->q);
		buffer_get_bignum2(&b, key->dsa->g);
		buffer_get_bignum2(&b, key->dsa->pub_key);
#ifdef DEBUG_PK
		DSA_print_fp(stderr, key->dsa, 8);
#endif
		break;
	case KEY_UNSPEC:
		key = key_new(type);
		break;
	default:
		error("key_from_blob: cannot handle type %s", ktype);
		break;
	}
	rlen = buffer_len(&b);
	if (key != NULL && rlen != 0)
		error("key_from_blob: remaining bytes in key blob %d", rlen);
	xfree(ktype);
	buffer_free(&b);
	return key;
}

int
key_to_blob(Key *key, u_char **blobp, u_int *lenp)
{
	Buffer b;
	int len;
	u_char *buf;

	if (key == NULL) {
		error("key_to_blob: key == NULL");
		return 0;
	}
	buffer_init(&b);
	switch(key->type){
	case KEY_DSA:
		buffer_put_cstring(&b, key_ssh_name(key));
		buffer_put_bignum2(&b, key->dsa->p);
		buffer_put_bignum2(&b, key->dsa->q);
		buffer_put_bignum2(&b, key->dsa->g);
		buffer_put_bignum2(&b, key->dsa->pub_key);
		break;
	case KEY_RSA:
		buffer_put_cstring(&b, key_ssh_name(key));
		buffer_put_bignum2(&b, key->rsa->e);
		buffer_put_bignum2(&b, key->rsa->n);
		break;
	default:
		error("key_to_blob: illegal key type %d", key->type);
		break;
	}
	len = buffer_len(&b);
	buf = xmalloc(len);
	memcpy(buf, buffer_ptr(&b), len);
	memset(buffer_ptr(&b), 0, len);
	buffer_free(&b);
	if (lenp != NULL)
		*lenp = len;
	if (blobp != NULL)
		*blobp = buf;
	return len;
}

int
key_sign(
    Key *key,
    u_char **sigp, int *lenp,
    u_char *data, int datalen)
{
	switch(key->type){
	case KEY_DSA:
		return ssh_dss_sign(key, sigp, lenp, data, datalen);
		break;
	case KEY_RSA:
		return ssh_rsa_sign(key, sigp, lenp, data, datalen);
		break;
	default:
		error("key_sign: illegal key type %d", key->type);
		return -1;
		break;
	}
}

int
key_verify(
    Key *key,
    u_char *signature, int signaturelen,
    u_char *data, int datalen)
{
	switch(key->type){
	case KEY_DSA:
		return ssh_dss_verify(key, signature, signaturelen, data, datalen);
		break;
	case KEY_RSA:
		return ssh_rsa_verify(key, signature, signaturelen, data, datalen);
		break;
	default:
		error("key_verify: illegal key type %d", key->type);
		return -1;
		break;
	}
}
Commit	Line	Data
4fe2af09	1	/*
bcbf86ec	2	* read_bignum():
	3	* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
	4	*
	5	* As far as I am concerned, the code I have written for this software
	6	* can be used freely for any purpose. Any derived versions of this
	7	* software must be clearly marked as such, and if the derived work is
	8	* incompatible with the protocol description in the RFC file, it must be
	9	* called by a name other than "ssh" or "Secure Shell".
	10	*
	11	*
4fe2af09	12	* Copyright (c) 2000 Markus Friedl. All rights reserved.
	13	*
	14	* Redistribution and use in source and binary forms, with or without
	15	* modification, are permitted provided that the following conditions
	16	* are met:
	17	* 1. Redistributions of source code must retain the above copyright
	18	* notice, this list of conditions and the following disclaimer.
	19	* 2. Redistributions in binary form must reproduce the above copyright
	20	* notice, this list of conditions and the following disclaimer in the
	21	* documentation and/or other materials provided with the distribution.
4fe2af09	22	*
	23	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
	24	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	25	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	26	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	27	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	28	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	29	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	30	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	31	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	32	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	33	*/
4fe2af09	34	#include "includes.h"
b35eb612	35	RCSID("$OpenBSD: key.c,v 1.17 2001/02/04 15:32:24 stevesk Exp $");
42f11eb2	36
4fe2af09	37	#include <openssl/evp.h>
42f11eb2	38
4fe2af09	39	#include "xmalloc.h"
4fe2af09	40	#include "key.h"
fa08c86b	41	#include "rsa.h"
	42	#include "ssh-dss.h"
	43	#include "ssh-rsa.h"
a306f2dd	44	#include "uuencode.h"
fa08c86b	45	#include "buffer.h"
fa08c86b	46	#include "bufaux.h"
42f11eb2	47	#include "log.h"
4fe2af09	48
	49	Key *
	50	key_new(int type)
	51	{
	52	Key *k;
	53	RSA *rsa;
	54	DSA *dsa;
	55	k = xmalloc(sizeof(*k));
	56	k->type = type;
a306f2dd	57	k->dsa = NULL;
a306f2dd	58	k->rsa = NULL;
4fe2af09	59	switch (k->type) {
fa08c86b	60	case KEY_RSA1:
4fe2af09	61	case KEY_RSA:
	62	rsa = RSA_new();
	63	rsa->n = BN_new();
	64	rsa->e = BN_new();
	65	k->rsa = rsa;
	66	break;
	67	case KEY_DSA:
	68	dsa = DSA_new();
	69	dsa->p = BN_new();
	70	dsa->q = BN_new();
	71	dsa->g = BN_new();
	72	dsa->pub_key = BN_new();
	73	k->dsa = dsa;
	74	break;
fa08c86b	75	case KEY_UNSPEC:
4fe2af09	76	break;
	77	default:
	78	fatal("key_new: bad key type %d", k->type);
	79	break;
	80	}
	81	return k;
	82	}
fa08c86b	83	Key *
	84	key_new_private(int type)
	85	{
	86	Key *k = key_new(type);
	87	switch (k->type) {
	88	case KEY_RSA1:
	89	case KEY_RSA:
	90	k->rsa->d = BN_new();
	91	k->rsa->iqmp = BN_new();
	92	k->rsa->q = BN_new();
	93	k->rsa->p = BN_new();
	94	k->rsa->dmq1 = BN_new();
	95	k->rsa->dmp1 = BN_new();
	96	break;
	97	case KEY_DSA:
	98	k->dsa->priv_key = BN_new();
	99	break;
	100	case KEY_UNSPEC:
	101	break;
	102	default:
	103	break;
	104	}
	105	return k;
	106	}
4fe2af09	107	void
	108	key_free(Key *k)
	109	{
	110	switch (k->type) {
fa08c86b	111	case KEY_RSA1:
4fe2af09	112	case KEY_RSA:
	113	if (k->rsa != NULL)
	114	RSA_free(k->rsa);
	115	k->rsa = NULL;
	116	break;
	117	case KEY_DSA:
	118	if (k->dsa != NULL)
	119	DSA_free(k->dsa);
	120	k->dsa = NULL;
	121	break;
fa08c86b	122	case KEY_UNSPEC:
fa08c86b	123	break;
4fe2af09	124	default:
	125	fatal("key_free: bad key type %d", k->type);
	126	break;
	127	}
	128	xfree(k);
	129	}
	130	int
	131	key_equal(Key a, Key b)
	132	{
	133	if (a == NULL \|\| b == NULL \|\| a->type != b->type)
	134	return 0;
	135	switch (a->type) {
fa08c86b	136	case KEY_RSA1:
4fe2af09	137	case KEY_RSA:
	138	return a->rsa != NULL && b->rsa != NULL &&
	139	BN_cmp(a->rsa->e, b->rsa->e) == 0 &&
	140	BN_cmp(a->rsa->n, b->rsa->n) == 0;
	141	break;
	142	case KEY_DSA:
	143	return a->dsa != NULL && b->dsa != NULL &&
	144	BN_cmp(a->dsa->p, b->dsa->p) == 0 &&
	145	BN_cmp(a->dsa->q, b->dsa->q) == 0 &&
	146	BN_cmp(a->dsa->g, b->dsa->g) == 0 &&
	147	BN_cmp(a->dsa->pub_key, b->dsa->pub_key) == 0;
	148	break;
	149	default:
a306f2dd	150	fatal("key_equal: bad key type %d", a->type);
4fe2af09	151	break;
	152	}
	153	return 0;
	154	}
	155
4fe2af09	156	/*
	157	* Generate key fingerprint in ascii format.
	158	* Based on ideas and code from Bjoern Groenvall <bg@sics.se>
	159	*/
	160	char *
	161	key_fingerprint(Key *k)
	162	{
74fc9186	163	static char retval[(EVP_MAX_MD_SIZE+1)*3];
1e3b8b07	164	u_char *blob = NULL;
4fe2af09	165	int len = 0;
a306f2dd	166	int nlen, elen;
4fe2af09	167
fa08c86b	168	retval[0] = '\0';
4fe2af09	169	switch (k->type) {
fa08c86b	170	case KEY_RSA1:
4fe2af09	171	nlen = BN_num_bytes(k->rsa->n);
	172	elen = BN_num_bytes(k->rsa->e);
	173	len = nlen + elen;
a306f2dd	174	blob = xmalloc(len);
	175	BN_bn2bin(k->rsa->n, blob);
	176	BN_bn2bin(k->rsa->e, blob + nlen);
4fe2af09	177	break;
4fe2af09	178	case KEY_DSA:
fa08c86b	179	case KEY_RSA:
	180	key_to_blob(k, &blob, &len);
	181	break;
	182	case KEY_UNSPEC:
	183	return retval;
4fe2af09	184	break;
	185	default:
	186	fatal("key_fingerprint: bad key type %d", k->type);
	187	break;
	188	}
a306f2dd	189	if (blob != NULL) {
74fc9186	190	int i;
1e3b8b07	191	u_char digest[EVP_MAX_MD_SIZE];
74fc9186	192	EVP_MD *md = EVP_md5();
	193	EVP_MD_CTX ctx;
	194	EVP_DigestInit(&ctx, md);
	195	EVP_DigestUpdate(&ctx, blob, len);
	196	EVP_DigestFinal(&ctx, digest, NULL);
	197	for(i = 0; i < md->md_size; i++) {
	198	char hex[4];
	199	snprintf(hex, sizeof(hex), "%02x:", digest[i]);
	200	strlcat(retval, hex, sizeof(retval));
	201	}
	202	retval[strlen(retval) - 1] = '\0';
a306f2dd	203	memset(blob, 0, len);
a306f2dd	204	xfree(blob);
4fe2af09	205	}
	206	return retval;
	207	}
	208
	209	/*
	210	* Reads a multiple-precision integer in decimal from the buffer, and advances
	211	* the pointer. The integer must already be initialized. This function is
	212	* permitted to modify the buffer. This leaves *cpp to point just beyond the
	213	* last processed (and maybe modified) character. Note that this may modify
	214	* the buffer containing the number.
	215	*/
	216	int
	217	read_bignum(char *cpp, BIGNUM value)
	218	{
	219	char cp = cpp;
	220	int old;
	221
	222	/* Skip any leading whitespace. */
	223	for (; cp == ' ' \|\| cp == '\t'; cp++)
	224	;
	225
	226	/* Check that it begins with a decimal digit. */
	227	if (cp < '0' \|\| cp > '9')
	228	return 0;
	229
	230	/* Save starting position. */
	231	*cpp = cp;
	232
	233	/* Move forward until all decimal digits skipped. */
	234	for (; cp >= '0' && cp <= '9'; cp++)
	235	;
	236
	237	/* Save the old terminating character, and replace it by \0. */
	238	old = *cp;
	239	*cp = 0;
	240
	241	/* Parse the number. */
	242	if (BN_dec2bn(&value, *cpp) == 0)
	243	return 0;
	244
	245	/* Restore old terminating character. */
	246	*cp = old;
	247
	248	/* Move beyond the number and return success. */
	249	*cpp = cp;
	250	return 1;
	251	}
	252	int
	253	write_bignum(FILE f, BIGNUM num)
	254	{
	255	char *buf = BN_bn2dec(num);
	256	if (buf == NULL) {
	257	error("write_bignum: BN_bn2dec() failed");
	258	return 0;
	259	}
	260	fprintf(f, " %s", buf);
53a24016	261	xfree(buf);
4fe2af09	262	return 1;
4fe2af09	263	}
fa08c86b	264
	265	/* returns 1 ok, -1 error, 0 type mismatch */
	266	int
a306f2dd	267	key_read(Key ret, char *cpp)
4fe2af09	268	{
a306f2dd	269	Key *k;
fa08c86b	270	int success = -1;
	271	char cp, space;
	272	int len, n, type;
	273	u_int bits;
1e3b8b07	274	u_char *blob;
a306f2dd	275
	276	cp = *cpp;
	277
4fe2af09	278	switch(ret->type) {
fa08c86b	279	case KEY_RSA1:
a306f2dd	280	/* Get number of bits. */
a306f2dd	281	if (cp < '0' \|\| cp > '9')
fa08c86b	282	return -1; /* Bad bit count... */
a306f2dd	283	for (bits = 0; cp >= '0' && cp <= '9'; cp++)
a306f2dd	284	bits = 10 * bits + *cp - '0';
4fe2af09	285	if (bits == 0)
fa08c86b	286	return -1;
a306f2dd	287	*cpp = cp;
4fe2af09	288	/* Get public exponent, public modulus. */
4fe2af09	289	if (!read_bignum(cpp, ret->rsa->e))
fa08c86b	290	return -1;
4fe2af09	291	if (!read_bignum(cpp, ret->rsa->n))
fa08c86b	292	return -1;
fa08c86b	293	success = 1;
4fe2af09	294	break;
fa08c86b	295	case KEY_UNSPEC:
fa08c86b	296	case KEY_RSA:
4fe2af09	297	case KEY_DSA:
fa08c86b	298	space = strchr(cp, ' ');
	299	if (space == NULL) {
	300	debug3("key_read: no space");
	301	return -1;
	302	}
	303	*space = '\0';
	304	type = key_type_from_name(cp);
	305	*space = ' ';
	306	if (type == KEY_UNSPEC) {
	307	debug3("key_read: no key found");
	308	return -1;
	309	}
	310	cp = space+1;
	311	if (*cp == '\0') {
	312	debug3("key_read: short string");
	313	return -1;
	314	}
	315	if (ret->type == KEY_UNSPEC) {
	316	ret->type = type;
	317	} else if (ret->type != type) {
	318	/* is a key, but different type */
	319	debug3("key_read: type mismatch");
4fe2af09	320	return 0;
fa08c86b	321	}
a306f2dd	322	len = 2*strlen(cp);
	323	blob = xmalloc(len);
	324	n = uudecode(cp, blob, len);
1d1ffb87	325	if (n < 0) {
71276795	326	error("key_read: uudecode %s failed", cp);
fa08c86b	327	return -1;
1d1ffb87	328	}
fa08c86b	329	k = key_from_blob(blob, n);
71276795	330	if (k == NULL) {
fa08c86b	331	error("key_read: key_from_blob %s failed", cp);
fa08c86b	332	return -1;
71276795	333	}
a306f2dd	334	xfree(blob);
fa08c86b	335	if (k->type != type) {
	336	error("key_read: type mismatch: encoding error");
	337	key_free(k);
	338	return -1;
	339	}
	340	/XXXX/
	341	if (ret->type == KEY_RSA) {
	342	if (ret->rsa != NULL)
	343	RSA_free(ret->rsa);
	344	ret->rsa = k->rsa;
	345	k->rsa = NULL;
	346	success = 1;
	347	#ifdef DEBUG_PK
	348	RSA_print_fp(stderr, ret->rsa, 8);
	349	#endif
	350	} else {
	351	if (ret->dsa != NULL)
	352	DSA_free(ret->dsa);
	353	ret->dsa = k->dsa;
	354	k->dsa = NULL;
	355	success = 1;
	356	#ifdef DEBUG_PK
	357	DSA_print_fp(stderr, ret->dsa, 8);
	358	#endif
	359	}
	360	/XXXX/
	361	if (success != 1)
	362	break;
a306f2dd	363	key_free(k);
71276795	364	/* advance cp: skip whitespace and data */
	365	while (cp == ' ' \|\| cp == '\t')
	366	cp++;
	367	while (cp != '\0' && cp != ' ' && *cp != '\t')
	368	cp++;
	369	*cpp = cp;
4fe2af09	370	break;
4fe2af09	371	default:
a306f2dd	372	fatal("key_read: bad key type: %d", ret->type);
4fe2af09	373	break;
4fe2af09	374	}
fa08c86b	375	return success;
4fe2af09	376	}
	377	int
	378	key_write(Key key, FILE f)
	379	{
	380	int success = 0;
1e3b8b07	381	u_int bits = 0;
4fe2af09	382
fa08c86b	383	if (key->type == KEY_RSA1 && key->rsa != NULL) {
4fe2af09	384	/* size of modulus 'n' */
	385	bits = BN_num_bits(key->rsa->n);
	386	fprintf(f, "%u", bits);
	387	if (write_bignum(f, key->rsa->e) &&
	388	write_bignum(f, key->rsa->n)) {
	389	success = 1;
	390	} else {
	391	error("key_write: failed for RSA key");
	392	}
fa08c86b	393	} else if ((key->type == KEY_DSA && key->dsa != NULL) \|\|
fa08c86b	394	(key->type == KEY_RSA && key->rsa != NULL)) {
a306f2dd	395	int len, n;
1e3b8b07	396	u_char blob, uu;
fa08c86b	397	key_to_blob(key, &blob, &len);
a306f2dd	398	uu = xmalloc(2*len);
1d1ffb87	399	n = uuencode(blob, len, uu, 2*len);
1d1ffb87	400	if (n > 0) {
fa08c86b	401	fprintf(f, "%s %s", key_ssh_name(key), uu);
1d1ffb87	402	success = 1;
1d1ffb87	403	}
a306f2dd	404	xfree(blob);
a306f2dd	405	xfree(uu);
4fe2af09	406	}
	407	return success;
	408	}
1d1ffb87	409	char *
	410	key_type(Key *k)
	411	{
	412	switch (k->type) {
fa08c86b	413	case KEY_RSA1:
	414	return "RSA1";
	415	break;
1d1ffb87	416	case KEY_RSA:
	417	return "RSA";
	418	break;
	419	case KEY_DSA:
	420	return "DSA";
	421	break;
	422	}
	423	return "unknown";
	424	}
fa08c86b	425	char *
	426	key_ssh_name(Key *k)
	427	{
	428	switch (k->type) {
	429	case KEY_RSA:
	430	return "ssh-rsa";
	431	break;
	432	case KEY_DSA:
	433	return "ssh-dss";
	434	break;
	435	}
	436	return "ssh-unknown";
	437	}
	438	u_int
2e73a022	439	key_size(Key *k){
2e73a022	440	switch (k->type) {
fa08c86b	441	case KEY_RSA1:
2e73a022	442	case KEY_RSA:
	443	return BN_num_bits(k->rsa->n);
	444	break;
	445	case KEY_DSA:
	446	return BN_num_bits(k->dsa->p);
	447	break;
	448	}
	449	return 0;
	450	}
fa08c86b	451
fa08c86b	452	RSA *
1e3b8b07	453	rsa_generate_private_key(u_int bits)
fa08c86b	454	{
2b87da3b	455	RSA *private;
	456	private = RSA_generate_key(bits, 35, NULL, NULL);
	457	if (private == NULL)
	458	fatal("rsa_generate_private_key: key generation failed.");
	459	return private;
fa08c86b	460	}
	461
	462	DSA*
1e3b8b07	463	dsa_generate_private_key(u_int bits)
fa08c86b	464	{
	465	DSA *private = DSA_generate_parameters(bits, NULL, 0, NULL, NULL, NULL, NULL);
	466	if (private == NULL)
	467	fatal("dsa_generate_private_key: DSA_generate_parameters failed");
	468	if (!DSA_generate_key(private))
2b87da3b	469	fatal("dsa_generate_private_key: DSA_generate_key failed.");
	470	if (private == NULL)
	471	fatal("dsa_generate_private_key: NULL.");
fa08c86b	472	return private;
	473	}
	474
	475	Key *
1e3b8b07	476	key_generate(int type, u_int bits)
fa08c86b	477	{
	478	Key *k = key_new(KEY_UNSPEC);
	479	switch (type) {
2b87da3b	480	case KEY_DSA:
fa08c86b	481	k->dsa = dsa_generate_private_key(bits);
	482	break;
	483	case KEY_RSA:
	484	case KEY_RSA1:
	485	k->rsa = rsa_generate_private_key(bits);
	486	break;
	487	default:
2b87da3b	488	fatal("key_generate: unknown type %d", type);
fa08c86b	489	}
2b87da3b	490	k->type = type;
fa08c86b	491	return k;
	492	}
	493
	494	Key *
	495	key_from_private(Key *k)
	496	{
	497	Key *n = NULL;
	498	switch (k->type) {
2b87da3b	499	case KEY_DSA:
fa08c86b	500	n = key_new(k->type);
	501	BN_copy(n->dsa->p, k->dsa->p);
	502	BN_copy(n->dsa->q, k->dsa->q);
	503	BN_copy(n->dsa->g, k->dsa->g);
	504	BN_copy(n->dsa->pub_key, k->dsa->pub_key);
	505	break;
	506	case KEY_RSA:
	507	case KEY_RSA1:
	508	n = key_new(k->type);
	509	BN_copy(n->rsa->n, k->rsa->n);
	510	BN_copy(n->rsa->e, k->rsa->e);
	511	break;
	512	default:
2b87da3b	513	fatal("key_from_private: unknown type %d", k->type);
fa08c86b	514	break;
	515	}
	516	return n;
	517	}
	518
	519	int
	520	key_type_from_name(char *name)
	521	{
	522	if (strcmp(name, "rsa1") == 0){
	523	return KEY_RSA1;
	524	} else if (strcmp(name, "rsa") == 0){
	525	return KEY_RSA;
	526	} else if (strcmp(name, "dsa") == 0){
	527	return KEY_DSA;
	528	} else if (strcmp(name, "ssh-rsa") == 0){
	529	return KEY_RSA;
	530	} else if (strcmp(name, "ssh-dss") == 0){
	531	return KEY_DSA;
	532	}
	533	debug("key_type_from_name: unknown key type '%s'", name);
	534	return KEY_UNSPEC;
	535	}
	536
	537	Key *
	538	key_from_blob(char *blob, int blen)
	539	{
	540	Buffer b;
	541	char *ktype;
	542	int rlen, type;
	543	Key *key = NULL;
	544
	545	#ifdef DEBUG_PK
	546	dump_base64(stderr, blob, blen);
	547	#endif
	548	buffer_init(&b);
	549	buffer_append(&b, blob, blen);
	550	ktype = buffer_get_string(&b, NULL);
	551	type = key_type_from_name(ktype);
	552
	553	switch(type){
	554	case KEY_RSA:
	555	key = key_new(type);
fa08c86b	556	buffer_get_bignum2(&b, key->rsa->e);
b5c334cc	557	buffer_get_bignum2(&b, key->rsa->n);
fa08c86b	558	#ifdef DEBUG_PK
	559	RSA_print_fp(stderr, key->rsa, 8);
	560	#endif
	561	break;
	562	case KEY_DSA:
	563	key = key_new(type);
	564	buffer_get_bignum2(&b, key->dsa->p);
	565	buffer_get_bignum2(&b, key->dsa->q);
	566	buffer_get_bignum2(&b, key->dsa->g);
	567	buffer_get_bignum2(&b, key->dsa->pub_key);
	568	#ifdef DEBUG_PK
	569	DSA_print_fp(stderr, key->dsa, 8);
	570	#endif
	571	break;
	572	case KEY_UNSPEC:
	573	key = key_new(type);
	574	break;
	575	default:
	576	error("key_from_blob: cannot handle type %s", ktype);
	577	break;
	578	}
	579	rlen = buffer_len(&b);
	580	if (key != NULL && rlen != 0)
	581	error("key_from_blob: remaining bytes in key blob %d", rlen);
	582	xfree(ktype);
	583	buffer_free(&b);
	584	return key;
	585	}
	586
	587	int
1e3b8b07	588	key_to_blob(Key key, u_char blobp, u_int lenp)
fa08c86b	589	{
	590	Buffer b;
	591	int len;
1e3b8b07	592	u_char *buf;
fa08c86b	593
	594	if (key == NULL) {
	595	error("key_to_blob: key == NULL");
	596	return 0;
	597	}
	598	buffer_init(&b);
	599	switch(key->type){
	600	case KEY_DSA:
	601	buffer_put_cstring(&b, key_ssh_name(key));
	602	buffer_put_bignum2(&b, key->dsa->p);
	603	buffer_put_bignum2(&b, key->dsa->q);
	604	buffer_put_bignum2(&b, key->dsa->g);
	605	buffer_put_bignum2(&b, key->dsa->pub_key);
	606	break;
	607	case KEY_RSA:
	608	buffer_put_cstring(&b, key_ssh_name(key));
fa08c86b	609	buffer_put_bignum2(&b, key->rsa->e);
b5c334cc	610	buffer_put_bignum2(&b, key->rsa->n);
fa08c86b	611	break;
	612	default:
	613	error("key_to_blob: illegal key type %d", key->type);
	614	break;
	615	}
	616	len = buffer_len(&b);
	617	buf = xmalloc(len);
	618	memcpy(buf, buffer_ptr(&b), len);
	619	memset(buffer_ptr(&b), 0, len);
	620	buffer_free(&b);
	621	if (lenp != NULL)
	622	*lenp = len;
	623	if (blobp != NULL)
	624	*blobp = buf;
	625	return len;
	626	}
	627
	628	int
	629	key_sign(
	630	Key *key,
1e3b8b07	631	u_char *sigp, int lenp,
1e3b8b07	632	u_char *data, int datalen)
fa08c86b	633	{
	634	switch(key->type){
	635	case KEY_DSA:
	636	return ssh_dss_sign(key, sigp, lenp, data, datalen);
	637	break;
	638	case KEY_RSA:
	639	return ssh_rsa_sign(key, sigp, lenp, data, datalen);
	640	break;
	641	default:
	642	error("key_sign: illegal key type %d", key->type);
	643	return -1;
	644	break;
	645	}
	646	}
	647
	648	int
	649	key_verify(
	650	Key *key,
1e3b8b07	651	u_char *signature, int signaturelen,
1e3b8b07	652	u_char *data, int datalen)
fa08c86b	653	{
	654	switch(key->type){
	655	case KEY_DSA:
	656	return ssh_dss_verify(key, signature, signaturelen, data, datalen);
	657	break;
	658	case KEY_RSA:
	659	return ssh_rsa_verify(key, signature, signaturelen, data, datalen);
	660	break;
	661	default:
	662	error("key_verify: illegal key type %d", key->type);
	663	return -1;
	664	break;
	665	}
	666	}