1 /* $OpenBSD: key.c,v 1.65 2006/07/22 20:48:23 stevesk Exp $ */
4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
6 * As far as I am concerned, the code I have written for this software
7 * can be used freely for any purpose. Any derived versions of this
8 * software must be clearly marked as such, and if the derived work is
9 * incompatible with the protocol description in the RFC file, it must be
10 * called by a name other than "ssh" or "Secure Shell".
13 * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
15 * Redistribution and use in source and binary forms, with or without
16 * modification, are permitted provided that the following conditions
18 * 1. Redistributions of source code must retain the above copyright
19 * notice, this list of conditions and the following disclaimer.
20 * 2. Redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions and the following disclaimer in the
22 * documentation and/or other materials provided with the distribution.
24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
31 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
37 #include <openssl/evp.h>
55 k = xcalloc(1, sizeof(*k));
62 if ((rsa = RSA_new()) == NULL)
63 fatal("key_new: RSA_new failed");
64 if ((rsa->n = BN_new()) == NULL)
65 fatal("key_new: BN_new failed");
66 if ((rsa->e = BN_new()) == NULL)
67 fatal("key_new: BN_new failed");
71 if ((dsa = DSA_new()) == NULL)
72 fatal("key_new: DSA_new failed");
73 if ((dsa->p = BN_new()) == NULL)
74 fatal("key_new: BN_new failed");
75 if ((dsa->q = BN_new()) == NULL)
76 fatal("key_new: BN_new failed");
77 if ((dsa->g = BN_new()) == NULL)
78 fatal("key_new: BN_new failed");
79 if ((dsa->pub_key = BN_new()) == NULL)
80 fatal("key_new: BN_new failed");
86 fatal("key_new: bad key type %d", k->type);
93 key_new_private(int type)
95 Key *k = key_new(type);
99 if ((k->rsa->d = BN_new()) == NULL)
100 fatal("key_new_private: BN_new failed");
101 if ((k->rsa->iqmp = BN_new()) == NULL)
102 fatal("key_new_private: BN_new failed");
103 if ((k->rsa->q = BN_new()) == NULL)
104 fatal("key_new_private: BN_new failed");
105 if ((k->rsa->p = BN_new()) == NULL)
106 fatal("key_new_private: BN_new failed");
107 if ((k->rsa->dmq1 = BN_new()) == NULL)
108 fatal("key_new_private: BN_new failed");
109 if ((k->rsa->dmp1 = BN_new()) == NULL)
110 fatal("key_new_private: BN_new failed");
113 if ((k->dsa->priv_key = BN_new()) == NULL)
114 fatal("key_new_private: BN_new failed");
128 fatal("key_free: key is NULL");
144 fatal("key_free: bad key type %d", k->type);
151 key_equal(const Key *a, const Key *b)
153 if (a == NULL || b == NULL || a->type != b->type)
158 return a->rsa != NULL && b->rsa != NULL &&
159 BN_cmp(a->rsa->e, b->rsa->e) == 0 &&
160 BN_cmp(a->rsa->n, b->rsa->n) == 0;
162 return a->dsa != NULL && b->dsa != NULL &&
163 BN_cmp(a->dsa->p, b->dsa->p) == 0 &&
164 BN_cmp(a->dsa->q, b->dsa->q) == 0 &&
165 BN_cmp(a->dsa->g, b->dsa->g) == 0 &&
166 BN_cmp(a->dsa->pub_key, b->dsa->pub_key) == 0;
168 fatal("key_equal: bad key type %d", a->type);
175 key_fingerprint_raw(const Key *k, enum fp_type dgst_type,
176 u_int *dgst_raw_length)
178 const EVP_MD *md = NULL;
181 u_char *retval = NULL;
185 *dgst_raw_length = 0;
195 fatal("key_fingerprint_raw: bad digest type %d",
200 nlen = BN_num_bytes(k->rsa->n);
201 elen = BN_num_bytes(k->rsa->e);
204 BN_bn2bin(k->rsa->n, blob);
205 BN_bn2bin(k->rsa->e, blob + nlen);
209 key_to_blob(k, &blob, &len);
214 fatal("key_fingerprint_raw: bad key type %d", k->type);
218 retval = xmalloc(EVP_MAX_MD_SIZE);
219 EVP_DigestInit(&ctx, md);
220 EVP_DigestUpdate(&ctx, blob, len);
221 EVP_DigestFinal(&ctx, retval, dgst_raw_length);
222 memset(blob, 0, len);
225 fatal("key_fingerprint_raw: blob is null");
231 key_fingerprint_hex(u_char *dgst_raw, u_int dgst_raw_len)
236 retval = xcalloc(1, dgst_raw_len * 3 + 1);
237 for (i = 0; i < dgst_raw_len; i++) {
239 snprintf(hex, sizeof(hex), "%02x:", dgst_raw[i]);
240 strlcat(retval, hex, dgst_raw_len * 3 + 1);
243 /* Remove the trailing ':' character */
244 retval[(dgst_raw_len * 3) - 1] = '\0';
249 key_fingerprint_bubblebabble(u_char *dgst_raw, u_int dgst_raw_len)
251 char vowels[] = { 'a', 'e', 'i', 'o', 'u', 'y' };
252 char consonants[] = { 'b', 'c', 'd', 'f', 'g', 'h', 'k', 'l', 'm',
253 'n', 'p', 'r', 's', 't', 'v', 'z', 'x' };
254 u_int i, j = 0, rounds, seed = 1;
257 rounds = (dgst_raw_len / 2) + 1;
258 retval = xcalloc((rounds * 6), sizeof(char));
260 for (i = 0; i < rounds; i++) {
261 u_int idx0, idx1, idx2, idx3, idx4;
262 if ((i + 1 < rounds) || (dgst_raw_len % 2 != 0)) {
263 idx0 = (((((u_int)(dgst_raw[2 * i])) >> 6) & 3) +
265 idx1 = (((u_int)(dgst_raw[2 * i])) >> 2) & 15;
266 idx2 = ((((u_int)(dgst_raw[2 * i])) & 3) +
268 retval[j++] = vowels[idx0];
269 retval[j++] = consonants[idx1];
270 retval[j++] = vowels[idx2];
271 if ((i + 1) < rounds) {
272 idx3 = (((u_int)(dgst_raw[(2 * i) + 1])) >> 4) & 15;
273 idx4 = (((u_int)(dgst_raw[(2 * i) + 1]))) & 15;
274 retval[j++] = consonants[idx3];
276 retval[j++] = consonants[idx4];
278 ((((u_int)(dgst_raw[2 * i])) * 7) +
279 ((u_int)(dgst_raw[(2 * i) + 1])))) % 36;
285 retval[j++] = vowels[idx0];
286 retval[j++] = consonants[idx1];
287 retval[j++] = vowels[idx2];
296 key_fingerprint(const Key *k, enum fp_type dgst_type, enum fp_rep dgst_rep)
302 dgst_raw = key_fingerprint_raw(k, dgst_type, &dgst_raw_len);
304 fatal("key_fingerprint: null from key_fingerprint_raw()");
307 retval = key_fingerprint_hex(dgst_raw, dgst_raw_len);
309 case SSH_FP_BUBBLEBABBLE:
310 retval = key_fingerprint_bubblebabble(dgst_raw, dgst_raw_len);
313 fatal("key_fingerprint_ex: bad digest representation %d",
317 memset(dgst_raw, 0, dgst_raw_len);
323 * Reads a multiple-precision integer in decimal from the buffer, and advances
324 * the pointer. The integer must already be initialized. This function is
325 * permitted to modify the buffer. This leaves *cpp to point just beyond the
326 * last processed (and maybe modified) character. Note that this may modify
327 * the buffer containing the number.
330 read_bignum(char **cpp, BIGNUM * value)
335 /* Skip any leading whitespace. */
336 for (; *cp == ' ' || *cp == '\t'; cp++)
339 /* Check that it begins with a decimal digit. */
340 if (*cp < '0' || *cp > '9')
343 /* Save starting position. */
346 /* Move forward until all decimal digits skipped. */
347 for (; *cp >= '0' && *cp <= '9'; cp++)
350 /* Save the old terminating character, and replace it by \0. */
354 /* Parse the number. */
355 if (BN_dec2bn(&value, *cpp) == 0)
358 /* Restore old terminating character. */
361 /* Move beyond the number and return success. */
367 write_bignum(FILE *f, BIGNUM *num)
369 char *buf = BN_bn2dec(num);
371 error("write_bignum: BN_bn2dec() failed");
374 fprintf(f, " %s", buf);
379 /* returns 1 ok, -1 error */
381 key_read(Key *ret, char **cpp)
394 /* Get number of bits. */
395 if (*cp < '0' || *cp > '9')
396 return -1; /* Bad bit count... */
397 for (bits = 0; *cp >= '0' && *cp <= '9'; cp++)
398 bits = 10 * bits + *cp - '0';
402 /* Get public exponent, public modulus. */
403 if (!read_bignum(cpp, ret->rsa->e))
405 if (!read_bignum(cpp, ret->rsa->n))
412 space = strchr(cp, ' ');
414 debug3("key_read: missing whitespace");
418 type = key_type_from_name(cp);
420 if (type == KEY_UNSPEC) {
421 debug3("key_read: missing keytype");
426 debug3("key_read: short string");
429 if (ret->type == KEY_UNSPEC) {
431 } else if (ret->type != type) {
432 /* is a key, but different type */
433 debug3("key_read: type mismatch");
438 n = uudecode(cp, blob, len);
440 error("key_read: uudecode %s failed", cp);
444 k = key_from_blob(blob, (u_int)n);
447 error("key_read: key_from_blob %s failed", cp);
450 if (k->type != type) {
451 error("key_read: type mismatch: encoding error");
456 if (ret->type == KEY_RSA) {
457 if (ret->rsa != NULL)
463 RSA_print_fp(stderr, ret->rsa, 8);
466 if (ret->dsa != NULL)
472 DSA_print_fp(stderr, ret->dsa, 8);
479 /* advance cp: skip whitespace and data */
480 while (*cp == ' ' || *cp == '\t')
482 while (*cp != '\0' && *cp != ' ' && *cp != '\t')
487 fatal("key_read: bad key type: %d", ret->type);
494 key_write(const Key *key, FILE *f)
501 if (key->type == KEY_RSA1 && key->rsa != NULL) {
502 /* size of modulus 'n' */
503 bits = BN_num_bits(key->rsa->n);
504 fprintf(f, "%u", bits);
505 if (write_bignum(f, key->rsa->e) &&
506 write_bignum(f, key->rsa->n)) {
509 error("key_write: failed for RSA key");
511 } else if ((key->type == KEY_DSA && key->dsa != NULL) ||
512 (key->type == KEY_RSA && key->rsa != NULL)) {
513 key_to_blob(key, &blob, &len);
515 n = uuencode(blob, len, uu, 2*len);
517 fprintf(f, "%s %s", key_ssh_name(key), uu);
527 key_type(const Key *k)
541 key_ssh_name(const Key *k)
549 return "ssh-unknown";
553 key_size(const Key *k)
558 return BN_num_bits(k->rsa->n);
560 return BN_num_bits(k->dsa->p);
566 rsa_generate_private_key(u_int bits)
570 private = RSA_generate_key(bits, 35, NULL, NULL);
572 fatal("rsa_generate_private_key: key generation failed.");
577 dsa_generate_private_key(u_int bits)
579 DSA *private = DSA_generate_parameters(bits, NULL, 0, NULL, NULL, NULL, NULL);
582 fatal("dsa_generate_private_key: DSA_generate_parameters failed");
583 if (!DSA_generate_key(private))
584 fatal("dsa_generate_private_key: DSA_generate_key failed.");
586 fatal("dsa_generate_private_key: NULL.");
591 key_generate(int type, u_int bits)
593 Key *k = key_new(KEY_UNSPEC);
596 k->dsa = dsa_generate_private_key(bits);
600 k->rsa = rsa_generate_private_key(bits);
603 fatal("key_generate: unknown type %d", type);
610 key_from_private(const Key *k)
615 n = key_new(k->type);
616 BN_copy(n->dsa->p, k->dsa->p);
617 BN_copy(n->dsa->q, k->dsa->q);
618 BN_copy(n->dsa->g, k->dsa->g);
619 BN_copy(n->dsa->pub_key, k->dsa->pub_key);
623 n = key_new(k->type);
624 BN_copy(n->rsa->n, k->rsa->n);
625 BN_copy(n->rsa->e, k->rsa->e);
628 fatal("key_from_private: unknown type %d", k->type);
635 key_type_from_name(char *name)
637 if (strcmp(name, "rsa1") == 0) {
639 } else if (strcmp(name, "rsa") == 0) {
641 } else if (strcmp(name, "dsa") == 0) {
643 } else if (strcmp(name, "ssh-rsa") == 0) {
645 } else if (strcmp(name, "ssh-dss") == 0) {
648 debug2("key_type_from_name: unknown key type '%s'", name);
653 key_names_valid2(const char *names)
657 if (names == NULL || strcmp(names, "") == 0)
659 s = cp = xstrdup(names);
660 for ((p = strsep(&cp, ",")); p && *p != '\0';
661 (p = strsep(&cp, ","))) {
662 switch (key_type_from_name(p)) {
669 debug3("key names ok: [%s]", names);
675 key_from_blob(const u_char *blob, u_int blen)
683 dump_base64(stderr, blob, blen);
686 buffer_append(&b, blob, blen);
687 if ((ktype = buffer_get_string_ret(&b, NULL)) == NULL) {
688 error("key_from_blob: can't read key type");
692 type = key_type_from_name(ktype);
697 if (buffer_get_bignum2_ret(&b, key->rsa->e) == -1 ||
698 buffer_get_bignum2_ret(&b, key->rsa->n) == -1) {
699 error("key_from_blob: can't read rsa key");
705 RSA_print_fp(stderr, key->rsa, 8);
710 if (buffer_get_bignum2_ret(&b, key->dsa->p) == -1 ||
711 buffer_get_bignum2_ret(&b, key->dsa->q) == -1 ||
712 buffer_get_bignum2_ret(&b, key->dsa->g) == -1 ||
713 buffer_get_bignum2_ret(&b, key->dsa->pub_key) == -1) {
714 error("key_from_blob: can't read dsa key");
720 DSA_print_fp(stderr, key->dsa, 8);
727 error("key_from_blob: cannot handle type %s", ktype);
730 rlen = buffer_len(&b);
731 if (key != NULL && rlen != 0)
732 error("key_from_blob: remaining bytes in key blob %d", rlen);
741 key_to_blob(const Key *key, u_char **blobp, u_int *lenp)
747 error("key_to_blob: key == NULL");
753 buffer_put_cstring(&b, key_ssh_name(key));
754 buffer_put_bignum2(&b, key->dsa->p);
755 buffer_put_bignum2(&b, key->dsa->q);
756 buffer_put_bignum2(&b, key->dsa->g);
757 buffer_put_bignum2(&b, key->dsa->pub_key);
760 buffer_put_cstring(&b, key_ssh_name(key));
761 buffer_put_bignum2(&b, key->rsa->e);
762 buffer_put_bignum2(&b, key->rsa->n);
765 error("key_to_blob: unsupported key type %d", key->type);
769 len = buffer_len(&b);
773 *blobp = xmalloc(len);
774 memcpy(*blobp, buffer_ptr(&b), len);
776 memset(buffer_ptr(&b), 0, len);
784 u_char **sigp, u_int *lenp,
785 const u_char *data, u_int datalen)
789 return ssh_dss_sign(key, sigp, lenp, data, datalen);
791 return ssh_rsa_sign(key, sigp, lenp, data, datalen);
793 error("key_sign: invalid key type %d", key->type);
799 * key_verify returns 1 for a correct signature, 0 for an incorrect signature
805 const u_char *signature, u_int signaturelen,
806 const u_char *data, u_int datalen)
808 if (signaturelen == 0)
813 return ssh_dss_verify(key, signature, signaturelen, data, datalen);
815 return ssh_rsa_verify(key, signature, signaturelen, data, datalen);
817 error("key_verify: invalid key type %d", key->type);
822 /* Converts a private to a public key */
824 key_demote(const Key *k)
828 pk = xcalloc(1, sizeof(*pk));
830 pk->flags = k->flags;
837 if ((pk->rsa = RSA_new()) == NULL)
838 fatal("key_demote: RSA_new failed");
839 if ((pk->rsa->e = BN_dup(k->rsa->e)) == NULL)
840 fatal("key_demote: BN_dup failed");
841 if ((pk->rsa->n = BN_dup(k->rsa->n)) == NULL)
842 fatal("key_demote: BN_dup failed");
845 if ((pk->dsa = DSA_new()) == NULL)
846 fatal("key_demote: DSA_new failed");
847 if ((pk->dsa->p = BN_dup(k->dsa->p)) == NULL)
848 fatal("key_demote: BN_dup failed");
849 if ((pk->dsa->q = BN_dup(k->dsa->q)) == NULL)
850 fatal("key_demote: BN_dup failed");
851 if ((pk->dsa->g = BN_dup(k->dsa->g)) == NULL)
852 fatal("key_demote: BN_dup failed");
853 if ((pk->dsa->pub_key = BN_dup(k->dsa->pub_key)) == NULL)
854 fatal("key_demote: BN_dup failed");
857 fatal("key_free: bad key type %d", k->type);