1 /* $OpenBSD: key.c,v 1.67 2006/08/03 03:34:42 deraadt 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.
38 #include <sys/types.h>
40 #include <openssl/evp.h>
58 k = xcalloc(1, sizeof(*k));
65 if ((rsa = RSA_new()) == NULL)
66 fatal("key_new: RSA_new failed");
67 if ((rsa->n = BN_new()) == NULL)
68 fatal("key_new: BN_new failed");
69 if ((rsa->e = BN_new()) == NULL)
70 fatal("key_new: BN_new failed");
74 if ((dsa = DSA_new()) == NULL)
75 fatal("key_new: DSA_new failed");
76 if ((dsa->p = BN_new()) == NULL)
77 fatal("key_new: BN_new failed");
78 if ((dsa->q = BN_new()) == NULL)
79 fatal("key_new: BN_new failed");
80 if ((dsa->g = BN_new()) == NULL)
81 fatal("key_new: BN_new failed");
82 if ((dsa->pub_key = BN_new()) == NULL)
83 fatal("key_new: BN_new failed");
89 fatal("key_new: bad key type %d", k->type);
96 key_new_private(int type)
98 Key *k = key_new(type);
102 if ((k->rsa->d = BN_new()) == NULL)
103 fatal("key_new_private: BN_new failed");
104 if ((k->rsa->iqmp = BN_new()) == NULL)
105 fatal("key_new_private: BN_new failed");
106 if ((k->rsa->q = BN_new()) == NULL)
107 fatal("key_new_private: BN_new failed");
108 if ((k->rsa->p = BN_new()) == NULL)
109 fatal("key_new_private: BN_new failed");
110 if ((k->rsa->dmq1 = BN_new()) == NULL)
111 fatal("key_new_private: BN_new failed");
112 if ((k->rsa->dmp1 = BN_new()) == NULL)
113 fatal("key_new_private: BN_new failed");
116 if ((k->dsa->priv_key = BN_new()) == NULL)
117 fatal("key_new_private: BN_new failed");
131 fatal("key_free: key is NULL");
147 fatal("key_free: bad key type %d", k->type);
154 key_equal(const Key *a, const Key *b)
156 if (a == NULL || b == NULL || a->type != b->type)
161 return a->rsa != NULL && b->rsa != NULL &&
162 BN_cmp(a->rsa->e, b->rsa->e) == 0 &&
163 BN_cmp(a->rsa->n, b->rsa->n) == 0;
165 return a->dsa != NULL && b->dsa != NULL &&
166 BN_cmp(a->dsa->p, b->dsa->p) == 0 &&
167 BN_cmp(a->dsa->q, b->dsa->q) == 0 &&
168 BN_cmp(a->dsa->g, b->dsa->g) == 0 &&
169 BN_cmp(a->dsa->pub_key, b->dsa->pub_key) == 0;
171 fatal("key_equal: bad key type %d", a->type);
178 key_fingerprint_raw(const Key *k, enum fp_type dgst_type,
179 u_int *dgst_raw_length)
181 const EVP_MD *md = NULL;
184 u_char *retval = NULL;
188 *dgst_raw_length = 0;
198 fatal("key_fingerprint_raw: bad digest type %d",
203 nlen = BN_num_bytes(k->rsa->n);
204 elen = BN_num_bytes(k->rsa->e);
207 BN_bn2bin(k->rsa->n, blob);
208 BN_bn2bin(k->rsa->e, blob + nlen);
212 key_to_blob(k, &blob, &len);
217 fatal("key_fingerprint_raw: bad key type %d", k->type);
221 retval = xmalloc(EVP_MAX_MD_SIZE);
222 EVP_DigestInit(&ctx, md);
223 EVP_DigestUpdate(&ctx, blob, len);
224 EVP_DigestFinal(&ctx, retval, dgst_raw_length);
225 memset(blob, 0, len);
228 fatal("key_fingerprint_raw: blob is null");
234 key_fingerprint_hex(u_char *dgst_raw, u_int dgst_raw_len)
239 retval = xcalloc(1, dgst_raw_len * 3 + 1);
240 for (i = 0; i < dgst_raw_len; i++) {
242 snprintf(hex, sizeof(hex), "%02x:", dgst_raw[i]);
243 strlcat(retval, hex, dgst_raw_len * 3 + 1);
246 /* Remove the trailing ':' character */
247 retval[(dgst_raw_len * 3) - 1] = '\0';
252 key_fingerprint_bubblebabble(u_char *dgst_raw, u_int dgst_raw_len)
254 char vowels[] = { 'a', 'e', 'i', 'o', 'u', 'y' };
255 char consonants[] = { 'b', 'c', 'd', 'f', 'g', 'h', 'k', 'l', 'm',
256 'n', 'p', 'r', 's', 't', 'v', 'z', 'x' };
257 u_int i, j = 0, rounds, seed = 1;
260 rounds = (dgst_raw_len / 2) + 1;
261 retval = xcalloc((rounds * 6), sizeof(char));
263 for (i = 0; i < rounds; i++) {
264 u_int idx0, idx1, idx2, idx3, idx4;
265 if ((i + 1 < rounds) || (dgst_raw_len % 2 != 0)) {
266 idx0 = (((((u_int)(dgst_raw[2 * i])) >> 6) & 3) +
268 idx1 = (((u_int)(dgst_raw[2 * i])) >> 2) & 15;
269 idx2 = ((((u_int)(dgst_raw[2 * i])) & 3) +
271 retval[j++] = vowels[idx0];
272 retval[j++] = consonants[idx1];
273 retval[j++] = vowels[idx2];
274 if ((i + 1) < rounds) {
275 idx3 = (((u_int)(dgst_raw[(2 * i) + 1])) >> 4) & 15;
276 idx4 = (((u_int)(dgst_raw[(2 * i) + 1]))) & 15;
277 retval[j++] = consonants[idx3];
279 retval[j++] = consonants[idx4];
281 ((((u_int)(dgst_raw[2 * i])) * 7) +
282 ((u_int)(dgst_raw[(2 * i) + 1])))) % 36;
288 retval[j++] = vowels[idx0];
289 retval[j++] = consonants[idx1];
290 retval[j++] = vowels[idx2];
299 key_fingerprint(const Key *k, enum fp_type dgst_type, enum fp_rep dgst_rep)
305 dgst_raw = key_fingerprint_raw(k, dgst_type, &dgst_raw_len);
307 fatal("key_fingerprint: null from key_fingerprint_raw()");
310 retval = key_fingerprint_hex(dgst_raw, dgst_raw_len);
312 case SSH_FP_BUBBLEBABBLE:
313 retval = key_fingerprint_bubblebabble(dgst_raw, dgst_raw_len);
316 fatal("key_fingerprint_ex: bad digest representation %d",
320 memset(dgst_raw, 0, dgst_raw_len);
326 * Reads a multiple-precision integer in decimal from the buffer, and advances
327 * the pointer. The integer must already be initialized. This function is
328 * permitted to modify the buffer. This leaves *cpp to point just beyond the
329 * last processed (and maybe modified) character. Note that this may modify
330 * the buffer containing the number.
333 read_bignum(char **cpp, BIGNUM * value)
338 /* Skip any leading whitespace. */
339 for (; *cp == ' ' || *cp == '\t'; cp++)
342 /* Check that it begins with a decimal digit. */
343 if (*cp < '0' || *cp > '9')
346 /* Save starting position. */
349 /* Move forward until all decimal digits skipped. */
350 for (; *cp >= '0' && *cp <= '9'; cp++)
353 /* Save the old terminating character, and replace it by \0. */
357 /* Parse the number. */
358 if (BN_dec2bn(&value, *cpp) == 0)
361 /* Restore old terminating character. */
364 /* Move beyond the number and return success. */
370 write_bignum(FILE *f, BIGNUM *num)
372 char *buf = BN_bn2dec(num);
374 error("write_bignum: BN_bn2dec() failed");
377 fprintf(f, " %s", buf);
382 /* returns 1 ok, -1 error */
384 key_read(Key *ret, char **cpp)
397 /* Get number of bits. */
398 if (*cp < '0' || *cp > '9')
399 return -1; /* Bad bit count... */
400 for (bits = 0; *cp >= '0' && *cp <= '9'; cp++)
401 bits = 10 * bits + *cp - '0';
405 /* Get public exponent, public modulus. */
406 if (!read_bignum(cpp, ret->rsa->e))
408 if (!read_bignum(cpp, ret->rsa->n))
415 space = strchr(cp, ' ');
417 debug3("key_read: missing whitespace");
421 type = key_type_from_name(cp);
423 if (type == KEY_UNSPEC) {
424 debug3("key_read: missing keytype");
429 debug3("key_read: short string");
432 if (ret->type == KEY_UNSPEC) {
434 } else if (ret->type != type) {
435 /* is a key, but different type */
436 debug3("key_read: type mismatch");
441 n = uudecode(cp, blob, len);
443 error("key_read: uudecode %s failed", cp);
447 k = key_from_blob(blob, (u_int)n);
450 error("key_read: key_from_blob %s failed", cp);
453 if (k->type != type) {
454 error("key_read: type mismatch: encoding error");
459 if (ret->type == KEY_RSA) {
460 if (ret->rsa != NULL)
466 RSA_print_fp(stderr, ret->rsa, 8);
469 if (ret->dsa != NULL)
475 DSA_print_fp(stderr, ret->dsa, 8);
482 /* advance cp: skip whitespace and data */
483 while (*cp == ' ' || *cp == '\t')
485 while (*cp != '\0' && *cp != ' ' && *cp != '\t')
490 fatal("key_read: bad key type: %d", ret->type);
497 key_write(const Key *key, FILE *f)
504 if (key->type == KEY_RSA1 && key->rsa != NULL) {
505 /* size of modulus 'n' */
506 bits = BN_num_bits(key->rsa->n);
507 fprintf(f, "%u", bits);
508 if (write_bignum(f, key->rsa->e) &&
509 write_bignum(f, key->rsa->n)) {
512 error("key_write: failed for RSA key");
514 } else if ((key->type == KEY_DSA && key->dsa != NULL) ||
515 (key->type == KEY_RSA && key->rsa != NULL)) {
516 key_to_blob(key, &blob, &len);
518 n = uuencode(blob, len, uu, 2*len);
520 fprintf(f, "%s %s", key_ssh_name(key), uu);
530 key_type(const Key *k)
544 key_ssh_name(const Key *k)
552 return "ssh-unknown";
556 key_size(const Key *k)
561 return BN_num_bits(k->rsa->n);
563 return BN_num_bits(k->dsa->p);
569 rsa_generate_private_key(u_int bits)
573 private = RSA_generate_key(bits, 35, NULL, NULL);
575 fatal("rsa_generate_private_key: key generation failed.");
580 dsa_generate_private_key(u_int bits)
582 DSA *private = DSA_generate_parameters(bits, NULL, 0, NULL, NULL, NULL, NULL);
585 fatal("dsa_generate_private_key: DSA_generate_parameters failed");
586 if (!DSA_generate_key(private))
587 fatal("dsa_generate_private_key: DSA_generate_key failed.");
589 fatal("dsa_generate_private_key: NULL.");
594 key_generate(int type, u_int bits)
596 Key *k = key_new(KEY_UNSPEC);
599 k->dsa = dsa_generate_private_key(bits);
603 k->rsa = rsa_generate_private_key(bits);
606 fatal("key_generate: unknown type %d", type);
613 key_from_private(const Key *k)
618 n = key_new(k->type);
619 BN_copy(n->dsa->p, k->dsa->p);
620 BN_copy(n->dsa->q, k->dsa->q);
621 BN_copy(n->dsa->g, k->dsa->g);
622 BN_copy(n->dsa->pub_key, k->dsa->pub_key);
626 n = key_new(k->type);
627 BN_copy(n->rsa->n, k->rsa->n);
628 BN_copy(n->rsa->e, k->rsa->e);
631 fatal("key_from_private: unknown type %d", k->type);
638 key_type_from_name(char *name)
640 if (strcmp(name, "rsa1") == 0) {
642 } else if (strcmp(name, "rsa") == 0) {
644 } else if (strcmp(name, "dsa") == 0) {
646 } else if (strcmp(name, "ssh-rsa") == 0) {
648 } else if (strcmp(name, "ssh-dss") == 0) {
651 debug2("key_type_from_name: unknown key type '%s'", name);
656 key_names_valid2(const char *names)
660 if (names == NULL || strcmp(names, "") == 0)
662 s = cp = xstrdup(names);
663 for ((p = strsep(&cp, ",")); p && *p != '\0';
664 (p = strsep(&cp, ","))) {
665 switch (key_type_from_name(p)) {
672 debug3("key names ok: [%s]", names);
678 key_from_blob(const u_char *blob, u_int blen)
686 dump_base64(stderr, blob, blen);
689 buffer_append(&b, blob, blen);
690 if ((ktype = buffer_get_string_ret(&b, NULL)) == NULL) {
691 error("key_from_blob: can't read key type");
695 type = key_type_from_name(ktype);
700 if (buffer_get_bignum2_ret(&b, key->rsa->e) == -1 ||
701 buffer_get_bignum2_ret(&b, key->rsa->n) == -1) {
702 error("key_from_blob: can't read rsa key");
708 RSA_print_fp(stderr, key->rsa, 8);
713 if (buffer_get_bignum2_ret(&b, key->dsa->p) == -1 ||
714 buffer_get_bignum2_ret(&b, key->dsa->q) == -1 ||
715 buffer_get_bignum2_ret(&b, key->dsa->g) == -1 ||
716 buffer_get_bignum2_ret(&b, key->dsa->pub_key) == -1) {
717 error("key_from_blob: can't read dsa key");
723 DSA_print_fp(stderr, key->dsa, 8);
730 error("key_from_blob: cannot handle type %s", ktype);
733 rlen = buffer_len(&b);
734 if (key != NULL && rlen != 0)
735 error("key_from_blob: remaining bytes in key blob %d", rlen);
744 key_to_blob(const Key *key, u_char **blobp, u_int *lenp)
750 error("key_to_blob: key == NULL");
756 buffer_put_cstring(&b, key_ssh_name(key));
757 buffer_put_bignum2(&b, key->dsa->p);
758 buffer_put_bignum2(&b, key->dsa->q);
759 buffer_put_bignum2(&b, key->dsa->g);
760 buffer_put_bignum2(&b, key->dsa->pub_key);
763 buffer_put_cstring(&b, key_ssh_name(key));
764 buffer_put_bignum2(&b, key->rsa->e);
765 buffer_put_bignum2(&b, key->rsa->n);
768 error("key_to_blob: unsupported key type %d", key->type);
772 len = buffer_len(&b);
776 *blobp = xmalloc(len);
777 memcpy(*blobp, buffer_ptr(&b), len);
779 memset(buffer_ptr(&b), 0, len);
787 u_char **sigp, u_int *lenp,
788 const u_char *data, u_int datalen)
792 return ssh_dss_sign(key, sigp, lenp, data, datalen);
794 return ssh_rsa_sign(key, sigp, lenp, data, datalen);
796 error("key_sign: invalid key type %d", key->type);
802 * key_verify returns 1 for a correct signature, 0 for an incorrect signature
808 const u_char *signature, u_int signaturelen,
809 const u_char *data, u_int datalen)
811 if (signaturelen == 0)
816 return ssh_dss_verify(key, signature, signaturelen, data, datalen);
818 return ssh_rsa_verify(key, signature, signaturelen, data, datalen);
820 error("key_verify: invalid key type %d", key->type);
825 /* Converts a private to a public key */
827 key_demote(const Key *k)
831 pk = xcalloc(1, sizeof(*pk));
833 pk->flags = k->flags;
840 if ((pk->rsa = RSA_new()) == NULL)
841 fatal("key_demote: RSA_new failed");
842 if ((pk->rsa->e = BN_dup(k->rsa->e)) == NULL)
843 fatal("key_demote: BN_dup failed");
844 if ((pk->rsa->n = BN_dup(k->rsa->n)) == NULL)
845 fatal("key_demote: BN_dup failed");
848 if ((pk->dsa = DSA_new()) == NULL)
849 fatal("key_demote: DSA_new failed");
850 if ((pk->dsa->p = BN_dup(k->dsa->p)) == NULL)
851 fatal("key_demote: BN_dup failed");
852 if ((pk->dsa->q = BN_dup(k->dsa->q)) == NULL)
853 fatal("key_demote: BN_dup failed");
854 if ((pk->dsa->g = BN_dup(k->dsa->g)) == NULL)
855 fatal("key_demote: BN_dup failed");
856 if ((pk->dsa->pub_key = BN_dup(k->dsa->pub_key)) == NULL)
857 fatal("key_demote: BN_dup failed");
860 fatal("key_free: bad key type %d", k->type);