Annotation of src/usr.bin/ssh/key.c, Revision 1.93
1.93 ! djm 1: /* $OpenBSD: key.c,v 1.92 2010/08/31 11:54:45 djm Exp $ */
1.1 markus 2: /*
1.11 deraadt 3: * read_bignum():
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: *
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".
11: *
12: *
1.28 markus 13: * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
1.76 grunk 14: * Copyright (c) 2008 Alexander von Gernler. All rights reserved.
1.1 markus 15: *
16: * Redistribution and use in source and binary forms, with or without
17: * modification, are permitted provided that the following conditions
18: * are met:
19: * 1. Redistributions of source code must retain the above copyright
20: * notice, this list of conditions and the following disclaimer.
21: * 2. Redistributions in binary form must reproduce the above copyright
22: * notice, this list of conditions and the following disclaimer in the
23: * documentation and/or other materials provided with the distribution.
24: *
25: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
26: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
28: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
29: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
30: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
31: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
32: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35: */
1.67 deraadt 36:
1.70 grunk 37: #include <sys/param.h>
1.67 deraadt 38: #include <sys/types.h>
1.1 markus 39:
1.2 markus 40: #include <openssl/evp.h>
1.65 stevesk 41:
1.66 stevesk 42: #include <stdio.h>
1.65 stevesk 43: #include <string.h>
1.15 markus 44:
1.1 markus 45: #include "xmalloc.h"
46: #include "key.h"
1.12 markus 47: #include "rsa.h"
1.3 markus 48: #include "uuencode.h"
1.12 markus 49: #include "buffer.h"
1.15 markus 50: #include "log.h"
1.89 djm 51: #include "misc.h"
1.83 djm 52: #include "ssh2.h"
53:
54: static struct KeyCert *
55: cert_new(void)
56: {
57: struct KeyCert *cert;
58:
59: cert = xcalloc(1, sizeof(*cert));
60: buffer_init(&cert->certblob);
1.87 djm 61: buffer_init(&cert->critical);
62: buffer_init(&cert->extensions);
1.83 djm 63: cert->key_id = NULL;
64: cert->principals = NULL;
65: cert->signature_key = NULL;
66: return cert;
67: }
1.1 markus 68:
69: Key *
70: key_new(int type)
71: {
72: Key *k;
73: RSA *rsa;
74: DSA *dsa;
1.63 djm 75: k = xcalloc(1, sizeof(*k));
1.1 markus 76: k->type = type;
1.92 djm 77: k->ecdsa = NULL;
78: k->ecdsa_nid = -1;
1.3 markus 79: k->dsa = NULL;
80: k->rsa = NULL;
1.83 djm 81: k->cert = NULL;
1.1 markus 82: switch (k->type) {
1.12 markus 83: case KEY_RSA1:
1.1 markus 84: case KEY_RSA:
1.87 djm 85: case KEY_RSA_CERT_V00:
1.83 djm 86: case KEY_RSA_CERT:
1.38 markus 87: if ((rsa = RSA_new()) == NULL)
88: fatal("key_new: RSA_new failed");
89: if ((rsa->n = BN_new()) == NULL)
90: fatal("key_new: BN_new failed");
91: if ((rsa->e = BN_new()) == NULL)
92: fatal("key_new: BN_new failed");
1.1 markus 93: k->rsa = rsa;
94: break;
95: case KEY_DSA:
1.87 djm 96: case KEY_DSA_CERT_V00:
1.83 djm 97: case KEY_DSA_CERT:
1.38 markus 98: if ((dsa = DSA_new()) == NULL)
99: fatal("key_new: DSA_new failed");
100: if ((dsa->p = BN_new()) == NULL)
101: fatal("key_new: BN_new failed");
102: if ((dsa->q = BN_new()) == NULL)
103: fatal("key_new: BN_new failed");
104: if ((dsa->g = BN_new()) == NULL)
105: fatal("key_new: BN_new failed");
106: if ((dsa->pub_key = BN_new()) == NULL)
107: fatal("key_new: BN_new failed");
1.1 markus 108: k->dsa = dsa;
109: break;
1.92 djm 110: case KEY_ECDSA:
111: case KEY_ECDSA_CERT:
112: /* Cannot do anything until we know the group */
113: break;
1.12 markus 114: case KEY_UNSPEC:
1.1 markus 115: break;
116: default:
117: fatal("key_new: bad key type %d", k->type);
118: break;
119: }
1.83 djm 120:
121: if (key_is_cert(k))
122: k->cert = cert_new();
123:
1.1 markus 124: return k;
125: }
1.45 deraadt 126:
1.83 djm 127: void
128: key_add_private(Key *k)
1.12 markus 129: {
130: switch (k->type) {
131: case KEY_RSA1:
132: case KEY_RSA:
1.87 djm 133: case KEY_RSA_CERT_V00:
1.83 djm 134: case KEY_RSA_CERT:
1.38 markus 135: if ((k->rsa->d = BN_new()) == NULL)
136: fatal("key_new_private: BN_new failed");
137: if ((k->rsa->iqmp = BN_new()) == NULL)
138: fatal("key_new_private: BN_new failed");
139: if ((k->rsa->q = BN_new()) == NULL)
140: fatal("key_new_private: BN_new failed");
141: if ((k->rsa->p = BN_new()) == NULL)
142: fatal("key_new_private: BN_new failed");
143: if ((k->rsa->dmq1 = BN_new()) == NULL)
144: fatal("key_new_private: BN_new failed");
145: if ((k->rsa->dmp1 = BN_new()) == NULL)
146: fatal("key_new_private: BN_new failed");
1.12 markus 147: break;
148: case KEY_DSA:
1.87 djm 149: case KEY_DSA_CERT_V00:
1.83 djm 150: case KEY_DSA_CERT:
1.38 markus 151: if ((k->dsa->priv_key = BN_new()) == NULL)
152: fatal("key_new_private: BN_new failed");
1.12 markus 153: break;
1.92 djm 154: case KEY_ECDSA:
155: case KEY_ECDSA_CERT:
156: /* Cannot do anything until we know the group */
157: break;
1.12 markus 158: case KEY_UNSPEC:
159: break;
160: default:
161: break;
162: }
1.83 djm 163: }
164:
165: Key *
166: key_new_private(int type)
167: {
168: Key *k = key_new(type);
169:
170: key_add_private(k);
1.12 markus 171: return k;
172: }
1.45 deraadt 173:
1.83 djm 174: static void
175: cert_free(struct KeyCert *cert)
176: {
177: u_int i;
178:
179: buffer_free(&cert->certblob);
1.87 djm 180: buffer_free(&cert->critical);
181: buffer_free(&cert->extensions);
1.83 djm 182: if (cert->key_id != NULL)
183: xfree(cert->key_id);
184: for (i = 0; i < cert->nprincipals; i++)
185: xfree(cert->principals[i]);
186: if (cert->principals != NULL)
187: xfree(cert->principals);
188: if (cert->signature_key != NULL)
189: key_free(cert->signature_key);
190: }
191:
1.1 markus 192: void
193: key_free(Key *k)
194: {
1.60 djm 195: if (k == NULL)
1.62 deraadt 196: fatal("key_free: key is NULL");
1.1 markus 197: switch (k->type) {
1.12 markus 198: case KEY_RSA1:
1.1 markus 199: case KEY_RSA:
1.87 djm 200: case KEY_RSA_CERT_V00:
1.83 djm 201: case KEY_RSA_CERT:
1.1 markus 202: if (k->rsa != NULL)
203: RSA_free(k->rsa);
204: k->rsa = NULL;
205: break;
206: case KEY_DSA:
1.87 djm 207: case KEY_DSA_CERT_V00:
1.83 djm 208: case KEY_DSA_CERT:
1.1 markus 209: if (k->dsa != NULL)
210: DSA_free(k->dsa);
211: k->dsa = NULL;
212: break;
1.92 djm 213: case KEY_ECDSA:
214: case KEY_ECDSA_CERT:
215: if (k->ecdsa != NULL)
216: EC_KEY_free(k->ecdsa);
217: k->ecdsa = NULL;
218: break;
1.12 markus 219: case KEY_UNSPEC:
220: break;
1.1 markus 221: default:
222: fatal("key_free: bad key type %d", k->type);
223: break;
224: }
1.83 djm 225: if (key_is_cert(k)) {
226: if (k->cert != NULL)
227: cert_free(k->cert);
228: k->cert = NULL;
229: }
230:
1.1 markus 231: xfree(k);
232: }
1.55 jakob 233:
1.83 djm 234: static int
235: cert_compare(struct KeyCert *a, struct KeyCert *b)
236: {
237: if (a == NULL && b == NULL)
238: return 1;
239: if (a == NULL || b == NULL)
240: return 0;
241: if (buffer_len(&a->certblob) != buffer_len(&b->certblob))
242: return 0;
1.90 djm 243: if (timingsafe_bcmp(buffer_ptr(&a->certblob), buffer_ptr(&b->certblob),
1.83 djm 244: buffer_len(&a->certblob)) != 0)
245: return 0;
246: return 1;
247: }
248:
249: /*
250: * Compare public portions of key only, allowing comparisons between
251: * certificates and plain keys too.
252: */
1.1 markus 253: int
1.83 djm 254: key_equal_public(const Key *a, const Key *b)
1.1 markus 255: {
1.92 djm 256: BN_CTX *bnctx;
257:
1.83 djm 258: if (a == NULL || b == NULL ||
259: key_type_plain(a->type) != key_type_plain(b->type))
1.1 markus 260: return 0;
1.83 djm 261:
1.1 markus 262: switch (a->type) {
1.12 markus 263: case KEY_RSA1:
1.87 djm 264: case KEY_RSA_CERT_V00:
1.83 djm 265: case KEY_RSA_CERT:
1.1 markus 266: case KEY_RSA:
267: return a->rsa != NULL && b->rsa != NULL &&
268: BN_cmp(a->rsa->e, b->rsa->e) == 0 &&
269: BN_cmp(a->rsa->n, b->rsa->n) == 0;
1.87 djm 270: case KEY_DSA_CERT_V00:
1.83 djm 271: case KEY_DSA_CERT:
1.1 markus 272: case KEY_DSA:
273: return a->dsa != NULL && b->dsa != NULL &&
274: BN_cmp(a->dsa->p, b->dsa->p) == 0 &&
275: BN_cmp(a->dsa->q, b->dsa->q) == 0 &&
276: BN_cmp(a->dsa->g, b->dsa->g) == 0 &&
277: BN_cmp(a->dsa->pub_key, b->dsa->pub_key) == 0;
1.92 djm 278: case KEY_ECDSA_CERT:
279: case KEY_ECDSA:
280: if (a->ecdsa == NULL || b->ecdsa == NULL ||
281: EC_KEY_get0_public_key(a->ecdsa) == NULL ||
282: EC_KEY_get0_public_key(b->ecdsa) == NULL)
283: return 0;
284: if ((bnctx = BN_CTX_new()) == NULL)
285: fatal("%s: BN_CTX_new failed", __func__);
286: if (EC_GROUP_cmp(EC_KEY_get0_group(a->ecdsa),
287: EC_KEY_get0_group(b->ecdsa), bnctx) != 0 ||
288: EC_POINT_cmp(EC_KEY_get0_group(a->ecdsa),
289: EC_KEY_get0_public_key(a->ecdsa),
290: EC_KEY_get0_public_key(b->ecdsa), bnctx) != 0) {
291: BN_CTX_free(bnctx);
292: return 0;
293: }
294: BN_CTX_free(bnctx);
295: return 1;
1.1 markus 296: default:
1.3 markus 297: fatal("key_equal: bad key type %d", a->type);
1.1 markus 298: }
1.78 stevesk 299: /* NOTREACHED */
1.1 markus 300: }
301:
1.83 djm 302: int
303: key_equal(const Key *a, const Key *b)
304: {
305: if (a == NULL || b == NULL || a->type != b->type)
306: return 0;
307: if (key_is_cert(a)) {
308: if (!cert_compare(a->cert, b->cert))
309: return 0;
310: }
311: return key_equal_public(a, b);
312: }
313:
1.52 jakob 314: u_char*
1.83 djm 315: key_fingerprint_raw(Key *k, enum fp_type dgst_type, u_int *dgst_raw_length)
1.1 markus 316: {
1.41 markus 317: const EVP_MD *md = NULL;
1.21 markus 318: EVP_MD_CTX ctx;
1.13 markus 319: u_char *blob = NULL;
1.19 jakob 320: u_char *retval = NULL;
1.40 markus 321: u_int len = 0;
1.83 djm 322: int nlen, elen, otype;
1.1 markus 323:
1.19 jakob 324: *dgst_raw_length = 0;
325:
1.21 markus 326: switch (dgst_type) {
327: case SSH_FP_MD5:
328: md = EVP_md5();
329: break;
330: case SSH_FP_SHA1:
331: md = EVP_sha1();
332: break;
333: default:
334: fatal("key_fingerprint_raw: bad digest type %d",
335: dgst_type);
336: }
1.1 markus 337: switch (k->type) {
1.12 markus 338: case KEY_RSA1:
1.1 markus 339: nlen = BN_num_bytes(k->rsa->n);
340: elen = BN_num_bytes(k->rsa->e);
341: len = nlen + elen;
1.3 markus 342: blob = xmalloc(len);
343: BN_bn2bin(k->rsa->n, blob);
344: BN_bn2bin(k->rsa->e, blob + nlen);
1.1 markus 345: break;
346: case KEY_DSA:
1.92 djm 347: case KEY_ECDSA:
1.12 markus 348: case KEY_RSA:
349: key_to_blob(k, &blob, &len);
350: break;
1.87 djm 351: case KEY_DSA_CERT_V00:
352: case KEY_RSA_CERT_V00:
1.83 djm 353: case KEY_DSA_CERT:
1.92 djm 354: case KEY_ECDSA_CERT:
1.83 djm 355: case KEY_RSA_CERT:
356: /* We want a fingerprint of the _key_ not of the cert */
357: otype = k->type;
358: k->type = key_type_plain(k->type);
359: key_to_blob(k, &blob, &len);
360: k->type = otype;
361: break;
1.12 markus 362: case KEY_UNSPEC:
363: return retval;
1.1 markus 364: default:
1.19 jakob 365: fatal("key_fingerprint_raw: bad key type %d", k->type);
1.1 markus 366: break;
367: }
1.3 markus 368: if (blob != NULL) {
1.19 jakob 369: retval = xmalloc(EVP_MAX_MD_SIZE);
1.8 markus 370: EVP_DigestInit(&ctx, md);
371: EVP_DigestUpdate(&ctx, blob, len);
1.39 markus 372: EVP_DigestFinal(&ctx, retval, dgst_raw_length);
1.3 markus 373: memset(blob, 0, len);
374: xfree(blob);
1.19 jakob 375: } else {
376: fatal("key_fingerprint_raw: blob is null");
1.1 markus 377: }
1.19 jakob 378: return retval;
379: }
380:
1.46 deraadt 381: static char *
382: key_fingerprint_hex(u_char *dgst_raw, u_int dgst_raw_len)
1.19 jakob 383: {
384: char *retval;
1.58 djm 385: u_int i;
1.19 jakob 386:
1.63 djm 387: retval = xcalloc(1, dgst_raw_len * 3 + 1);
1.36 deraadt 388: for (i = 0; i < dgst_raw_len; i++) {
1.19 jakob 389: char hex[4];
390: snprintf(hex, sizeof(hex), "%02x:", dgst_raw[i]);
1.54 avsm 391: strlcat(retval, hex, dgst_raw_len * 3 + 1);
1.19 jakob 392: }
1.54 avsm 393:
394: /* Remove the trailing ':' character */
1.19 jakob 395: retval[(dgst_raw_len * 3) - 1] = '\0';
396: return retval;
397: }
398:
1.46 deraadt 399: static char *
400: key_fingerprint_bubblebabble(u_char *dgst_raw, u_int dgst_raw_len)
1.19 jakob 401: {
402: char vowels[] = { 'a', 'e', 'i', 'o', 'u', 'y' };
403: char consonants[] = { 'b', 'c', 'd', 'f', 'g', 'h', 'k', 'l', 'm',
404: 'n', 'p', 'r', 's', 't', 'v', 'z', 'x' };
1.20 jakob 405: u_int i, j = 0, rounds, seed = 1;
1.19 jakob 406: char *retval;
407:
408: rounds = (dgst_raw_len / 2) + 1;
1.63 djm 409: retval = xcalloc((rounds * 6), sizeof(char));
1.20 jakob 410: retval[j++] = 'x';
411: for (i = 0; i < rounds; i++) {
1.19 jakob 412: u_int idx0, idx1, idx2, idx3, idx4;
1.20 jakob 413: if ((i + 1 < rounds) || (dgst_raw_len % 2 != 0)) {
414: idx0 = (((((u_int)(dgst_raw[2 * i])) >> 6) & 3) +
1.19 jakob 415: seed) % 6;
1.20 jakob 416: idx1 = (((u_int)(dgst_raw[2 * i])) >> 2) & 15;
417: idx2 = ((((u_int)(dgst_raw[2 * i])) & 3) +
1.19 jakob 418: (seed / 6)) % 6;
1.20 jakob 419: retval[j++] = vowels[idx0];
420: retval[j++] = consonants[idx1];
421: retval[j++] = vowels[idx2];
422: if ((i + 1) < rounds) {
423: idx3 = (((u_int)(dgst_raw[(2 * i) + 1])) >> 4) & 15;
424: idx4 = (((u_int)(dgst_raw[(2 * i) + 1]))) & 15;
425: retval[j++] = consonants[idx3];
426: retval[j++] = '-';
427: retval[j++] = consonants[idx4];
1.19 jakob 428: seed = ((seed * 5) +
1.20 jakob 429: ((((u_int)(dgst_raw[2 * i])) * 7) +
430: ((u_int)(dgst_raw[(2 * i) + 1])))) % 36;
1.19 jakob 431: }
432: } else {
433: idx0 = seed % 6;
434: idx1 = 16;
435: idx2 = seed / 6;
1.20 jakob 436: retval[j++] = vowels[idx0];
437: retval[j++] = consonants[idx1];
438: retval[j++] = vowels[idx2];
1.19 jakob 439: }
440: }
1.20 jakob 441: retval[j++] = 'x';
442: retval[j++] = '\0';
1.19 jakob 443: return retval;
444: }
445:
1.70 grunk 446: /*
447: * Draw an ASCII-Art representing the fingerprint so human brain can
448: * profit from its built-in pattern recognition ability.
449: * This technique is called "random art" and can be found in some
450: * scientific publications like this original paper:
451: *
452: * "Hash Visualization: a New Technique to improve Real-World Security",
453: * Perrig A. and Song D., 1999, International Workshop on Cryptographic
454: * Techniques and E-Commerce (CrypTEC '99)
455: * sparrow.ece.cmu.edu/~adrian/projects/validation/validation.pdf
456: *
457: * The subject came up in a talk by Dan Kaminsky, too.
458: *
459: * If you see the picture is different, the key is different.
460: * If the picture looks the same, you still know nothing.
461: *
462: * The algorithm used here is a worm crawling over a discrete plane,
463: * leaving a trace (augmenting the field) everywhere it goes.
464: * Movement is taken from dgst_raw 2bit-wise. Bumping into walls
465: * makes the respective movement vector be ignored for this turn.
466: * Graphs are not unambiguous, because circles in graphs can be
467: * walked in either direction.
468: */
1.74 grunk 469:
470: /*
471: * Field sizes for the random art. Have to be odd, so the starting point
472: * can be in the exact middle of the picture, and FLDBASE should be >=8 .
473: * Else pictures would be too dense, and drawing the frame would
474: * fail, too, because the key type would not fit in anymore.
475: */
476: #define FLDBASE 8
477: #define FLDSIZE_Y (FLDBASE + 1)
478: #define FLDSIZE_X (FLDBASE * 2 + 1)
1.70 grunk 479: static char *
1.74 grunk 480: key_fingerprint_randomart(u_char *dgst_raw, u_int dgst_raw_len, const Key *k)
1.70 grunk 481: {
482: /*
483: * Chars to be used after each other every time the worm
484: * intersects with itself. Matter of taste.
485: */
1.75 grunk 486: char *augmentation_string = " .o+=*BOX@%&#/^SE";
1.70 grunk 487: char *retval, *p;
1.71 otto 488: u_char field[FLDSIZE_X][FLDSIZE_Y];
1.70 grunk 489: u_int i, b;
490: int x, y;
1.72 grunk 491: size_t len = strlen(augmentation_string) - 1;
1.70 grunk 492:
493: retval = xcalloc(1, (FLDSIZE_X + 3) * (FLDSIZE_Y + 2));
494:
495: /* initialize field */
1.71 otto 496: memset(field, 0, FLDSIZE_X * FLDSIZE_Y * sizeof(char));
1.70 grunk 497: x = FLDSIZE_X / 2;
498: y = FLDSIZE_Y / 2;
499:
500: /* process raw key */
501: for (i = 0; i < dgst_raw_len; i++) {
502: int input;
503: /* each byte conveys four 2-bit move commands */
504: input = dgst_raw[i];
505: for (b = 0; b < 4; b++) {
506: /* evaluate 2 bit, rest is shifted later */
507: x += (input & 0x1) ? 1 : -1;
508: y += (input & 0x2) ? 1 : -1;
509:
510: /* assure we are still in bounds */
511: x = MAX(x, 0);
512: y = MAX(y, 0);
513: x = MIN(x, FLDSIZE_X - 1);
514: y = MIN(y, FLDSIZE_Y - 1);
515:
516: /* augment the field */
1.79 grunk 517: if (field[x][y] < len - 2)
518: field[x][y]++;
1.70 grunk 519: input = input >> 2;
520: }
521: }
1.75 grunk 522:
523: /* mark starting point and end point*/
524: field[FLDSIZE_X / 2][FLDSIZE_Y / 2] = len - 1;
525: field[x][y] = len;
1.70 grunk 526:
527: /* fill in retval */
1.77 otto 528: snprintf(retval, FLDSIZE_X, "+--[%4s %4u]", key_type(k), key_size(k));
1.74 grunk 529: p = strchr(retval, '\0');
1.70 grunk 530:
531: /* output upper border */
1.77 otto 532: for (i = p - retval - 1; i < FLDSIZE_X; i++)
1.70 grunk 533: *p++ = '-';
534: *p++ = '+';
535: *p++ = '\n';
536:
537: /* output content */
538: for (y = 0; y < FLDSIZE_Y; y++) {
539: *p++ = '|';
540: for (x = 0; x < FLDSIZE_X; x++)
1.72 grunk 541: *p++ = augmentation_string[MIN(field[x][y], len)];
1.70 grunk 542: *p++ = '|';
543: *p++ = '\n';
544: }
545:
546: /* output lower border */
547: *p++ = '+';
548: for (i = 0; i < FLDSIZE_X; i++)
549: *p++ = '-';
550: *p++ = '+';
551:
552: return retval;
553: }
554:
1.46 deraadt 555: char *
1.83 djm 556: key_fingerprint(Key *k, enum fp_type dgst_type, enum fp_rep dgst_rep)
1.19 jakob 557: {
1.23 markus 558: char *retval = NULL;
1.19 jakob 559: u_char *dgst_raw;
1.39 markus 560: u_int dgst_raw_len;
1.36 deraadt 561:
1.19 jakob 562: dgst_raw = key_fingerprint_raw(k, dgst_type, &dgst_raw_len);
563: if (!dgst_raw)
1.22 markus 564: fatal("key_fingerprint: null from key_fingerprint_raw()");
1.35 deraadt 565: switch (dgst_rep) {
1.19 jakob 566: case SSH_FP_HEX:
567: retval = key_fingerprint_hex(dgst_raw, dgst_raw_len);
568: break;
569: case SSH_FP_BUBBLEBABBLE:
570: retval = key_fingerprint_bubblebabble(dgst_raw, dgst_raw_len);
1.70 grunk 571: break;
572: case SSH_FP_RANDOMART:
1.74 grunk 573: retval = key_fingerprint_randomart(dgst_raw, dgst_raw_len, k);
1.19 jakob 574: break;
575: default:
1.80 stevesk 576: fatal("key_fingerprint: bad digest representation %d",
1.19 jakob 577: dgst_rep);
578: break;
579: }
580: memset(dgst_raw, 0, dgst_raw_len);
581: xfree(dgst_raw);
1.1 markus 582: return retval;
583: }
584:
585: /*
586: * Reads a multiple-precision integer in decimal from the buffer, and advances
587: * the pointer. The integer must already be initialized. This function is
588: * permitted to modify the buffer. This leaves *cpp to point just beyond the
589: * last processed (and maybe modified) character. Note that this may modify
590: * the buffer containing the number.
591: */
1.27 itojun 592: static int
1.1 markus 593: read_bignum(char **cpp, BIGNUM * value)
594: {
595: char *cp = *cpp;
596: int old;
597:
598: /* Skip any leading whitespace. */
599: for (; *cp == ' ' || *cp == '\t'; cp++)
600: ;
601:
602: /* Check that it begins with a decimal digit. */
603: if (*cp < '0' || *cp > '9')
604: return 0;
605:
606: /* Save starting position. */
607: *cpp = cp;
608:
609: /* Move forward until all decimal digits skipped. */
610: for (; *cp >= '0' && *cp <= '9'; cp++)
611: ;
612:
613: /* Save the old terminating character, and replace it by \0. */
614: old = *cp;
615: *cp = 0;
616:
617: /* Parse the number. */
618: if (BN_dec2bn(&value, *cpp) == 0)
619: return 0;
620:
621: /* Restore old terminating character. */
622: *cp = old;
623:
624: /* Move beyond the number and return success. */
625: *cpp = cp;
626: return 1;
627: }
1.45 deraadt 628:
1.27 itojun 629: static int
1.1 markus 630: write_bignum(FILE *f, BIGNUM *num)
631: {
632: char *buf = BN_bn2dec(num);
633: if (buf == NULL) {
634: error("write_bignum: BN_bn2dec() failed");
635: return 0;
636: }
637: fprintf(f, " %s", buf);
1.33 markus 638: OPENSSL_free(buf);
1.1 markus 639: return 1;
640: }
1.12 markus 641:
1.32 markus 642: /* returns 1 ok, -1 error */
1.12 markus 643: int
1.3 markus 644: key_read(Key *ret, char **cpp)
1.1 markus 645: {
1.3 markus 646: Key *k;
1.12 markus 647: int success = -1;
648: char *cp, *space;
1.92 djm 649: int len, n, type, curve_nid = -1;
1.12 markus 650: u_int bits;
1.13 markus 651: u_char *blob;
1.3 markus 652:
653: cp = *cpp;
654:
1.35 deraadt 655: switch (ret->type) {
1.12 markus 656: case KEY_RSA1:
1.3 markus 657: /* Get number of bits. */
658: if (*cp < '0' || *cp > '9')
1.12 markus 659: return -1; /* Bad bit count... */
1.3 markus 660: for (bits = 0; *cp >= '0' && *cp <= '9'; cp++)
661: bits = 10 * bits + *cp - '0';
1.1 markus 662: if (bits == 0)
1.12 markus 663: return -1;
1.3 markus 664: *cpp = cp;
1.1 markus 665: /* Get public exponent, public modulus. */
666: if (!read_bignum(cpp, ret->rsa->e))
1.12 markus 667: return -1;
1.1 markus 668: if (!read_bignum(cpp, ret->rsa->n))
1.12 markus 669: return -1;
1.82 dtucker 670: /* validate the claimed number of bits */
671: if ((u_int)BN_num_bits(ret->rsa->n) != bits) {
672: verbose("key_read: claimed key size %d does not match "
673: "actual %d", bits, BN_num_bits(ret->rsa->n));
674: return -1;
675: }
1.12 markus 676: success = 1;
1.1 markus 677: break;
1.12 markus 678: case KEY_UNSPEC:
679: case KEY_RSA:
1.1 markus 680: case KEY_DSA:
1.92 djm 681: case KEY_ECDSA:
1.87 djm 682: case KEY_DSA_CERT_V00:
683: case KEY_RSA_CERT_V00:
1.83 djm 684: case KEY_DSA_CERT:
1.92 djm 685: case KEY_ECDSA_CERT:
1.83 djm 686: case KEY_RSA_CERT:
1.12 markus 687: space = strchr(cp, ' ');
688: if (space == NULL) {
1.50 markus 689: debug3("key_read: missing whitespace");
1.12 markus 690: return -1;
691: }
692: *space = '\0';
693: type = key_type_from_name(cp);
1.92 djm 694: if (key_type_plain(type) == KEY_ECDSA &&
695: (curve_nid = key_ecdsa_nid_from_name(cp)) == -1) {
696: debug("key_read: invalid curve");
697: return -1;
698: }
1.12 markus 699: *space = ' ';
700: if (type == KEY_UNSPEC) {
1.50 markus 701: debug3("key_read: missing keytype");
1.12 markus 702: return -1;
703: }
704: cp = space+1;
705: if (*cp == '\0') {
706: debug3("key_read: short string");
707: return -1;
708: }
709: if (ret->type == KEY_UNSPEC) {
710: ret->type = type;
711: } else if (ret->type != type) {
712: /* is a key, but different type */
713: debug3("key_read: type mismatch");
1.32 markus 714: return -1;
1.12 markus 715: }
1.3 markus 716: len = 2*strlen(cp);
717: blob = xmalloc(len);
718: n = uudecode(cp, blob, len);
1.6 markus 719: if (n < 0) {
1.7 markus 720: error("key_read: uudecode %s failed", cp);
1.34 markus 721: xfree(blob);
1.12 markus 722: return -1;
1.6 markus 723: }
1.53 markus 724: k = key_from_blob(blob, (u_int)n);
1.34 markus 725: xfree(blob);
1.7 markus 726: if (k == NULL) {
1.12 markus 727: error("key_read: key_from_blob %s failed", cp);
728: return -1;
1.7 markus 729: }
1.12 markus 730: if (k->type != type) {
731: error("key_read: type mismatch: encoding error");
732: key_free(k);
733: return -1;
734: }
1.92 djm 735: if (key_type_plain(type) == KEY_ECDSA &&
736: curve_nid != k->ecdsa_nid) {
737: error("key_read: type mismatch: EC curve mismatch");
738: key_free(k);
739: return -1;
740: }
1.12 markus 741: /*XXXX*/
1.83 djm 742: if (key_is_cert(ret)) {
743: if (!key_is_cert(k)) {
744: error("key_read: loaded key is not a cert");
745: key_free(k);
746: return -1;
747: }
748: if (ret->cert != NULL)
749: cert_free(ret->cert);
750: ret->cert = k->cert;
751: k->cert = NULL;
752: }
753: if (key_type_plain(ret->type) == KEY_RSA) {
1.12 markus 754: if (ret->rsa != NULL)
755: RSA_free(ret->rsa);
756: ret->rsa = k->rsa;
757: k->rsa = NULL;
758: #ifdef DEBUG_PK
759: RSA_print_fp(stderr, ret->rsa, 8);
760: #endif
1.83 djm 761: }
762: if (key_type_plain(ret->type) == KEY_DSA) {
1.12 markus 763: if (ret->dsa != NULL)
764: DSA_free(ret->dsa);
765: ret->dsa = k->dsa;
766: k->dsa = NULL;
767: #ifdef DEBUG_PK
768: DSA_print_fp(stderr, ret->dsa, 8);
769: #endif
770: }
1.92 djm 771: if (key_type_plain(ret->type) == KEY_ECDSA) {
772: if (ret->ecdsa != NULL)
773: EC_KEY_free(ret->ecdsa);
774: ret->ecdsa = k->ecdsa;
775: ret->ecdsa_nid = k->ecdsa_nid;
776: k->ecdsa = NULL;
777: k->ecdsa_nid = -1;
778: #ifdef DEBUG_PK
779: key_dump_ec_key(ret->ecdsa);
780: #endif
781: }
1.83 djm 782: success = 1;
1.12 markus 783: /*XXXX*/
1.34 markus 784: key_free(k);
1.12 markus 785: if (success != 1)
786: break;
1.7 markus 787: /* advance cp: skip whitespace and data */
788: while (*cp == ' ' || *cp == '\t')
789: cp++;
790: while (*cp != '\0' && *cp != ' ' && *cp != '\t')
791: cp++;
792: *cpp = cp;
1.1 markus 793: break;
794: default:
1.3 markus 795: fatal("key_read: bad key type: %d", ret->type);
1.1 markus 796: break;
797: }
1.12 markus 798: return success;
1.1 markus 799: }
1.45 deraadt 800:
1.1 markus 801: int
1.55 jakob 802: key_write(const Key *key, FILE *f)
1.1 markus 803: {
1.40 markus 804: int n, success = 0;
805: u_int len, bits = 0;
1.49 markus 806: u_char *blob;
807: char *uu;
1.1 markus 808:
1.83 djm 809: if (key_is_cert(key)) {
810: if (key->cert == NULL) {
811: error("%s: no cert data", __func__);
812: return 0;
813: }
814: if (buffer_len(&key->cert->certblob) == 0) {
815: error("%s: no signed certificate blob", __func__);
816: return 0;
817: }
818: }
819:
820: switch (key->type) {
821: case KEY_RSA1:
822: if (key->rsa == NULL)
823: return 0;
1.1 markus 824: /* size of modulus 'n' */
825: bits = BN_num_bits(key->rsa->n);
826: fprintf(f, "%u", bits);
827: if (write_bignum(f, key->rsa->e) &&
1.83 djm 828: write_bignum(f, key->rsa->n))
829: return 1;
830: error("key_write: failed for RSA key");
831: return 0;
832: case KEY_DSA:
1.87 djm 833: case KEY_DSA_CERT_V00:
1.83 djm 834: case KEY_DSA_CERT:
835: if (key->dsa == NULL)
836: return 0;
837: break;
1.92 djm 838: case KEY_ECDSA:
839: case KEY_ECDSA_CERT:
840: if (key->ecdsa == NULL)
841: return 0;
842: break;
1.83 djm 843: case KEY_RSA:
1.87 djm 844: case KEY_RSA_CERT_V00:
1.83 djm 845: case KEY_RSA_CERT:
846: if (key->rsa == NULL)
847: return 0;
848: break;
849: default:
850: return 0;
851: }
852:
853: key_to_blob(key, &blob, &len);
854: uu = xmalloc(2*len);
855: n = uuencode(blob, len, uu, 2*len);
856: if (n > 0) {
857: fprintf(f, "%s %s", key_ssh_name(key), uu);
858: success = 1;
1.1 markus 859: }
1.83 djm 860: xfree(blob);
861: xfree(uu);
862:
1.1 markus 863: return success;
864: }
1.45 deraadt 865:
1.55 jakob 866: const char *
867: key_type(const Key *k)
1.4 markus 868: {
869: switch (k->type) {
1.12 markus 870: case KEY_RSA1:
871: return "RSA1";
1.4 markus 872: case KEY_RSA:
873: return "RSA";
874: case KEY_DSA:
875: return "DSA";
1.92 djm 876: case KEY_ECDSA:
877: return "ECDSA";
1.87 djm 878: case KEY_RSA_CERT_V00:
879: return "RSA-CERT-V00";
880: case KEY_DSA_CERT_V00:
881: return "DSA-CERT-V00";
1.83 djm 882: case KEY_RSA_CERT:
883: return "RSA-CERT";
884: case KEY_DSA_CERT:
885: return "DSA-CERT";
1.92 djm 886: case KEY_ECDSA_CERT:
887: return "ECDSA-CERT";
1.4 markus 888: }
889: return "unknown";
1.86 stevesk 890: }
891:
892: const char *
893: key_cert_type(const Key *k)
894: {
895: switch (k->cert->type) {
896: case SSH2_CERT_TYPE_USER:
897: return "user";
898: case SSH2_CERT_TYPE_HOST:
899: return "host";
900: default:
901: return "unknown";
902: }
1.10 markus 903: }
1.45 deraadt 904:
1.92 djm 905: static const char *
906: key_ssh_name_from_type_nid(int type, int nid)
1.12 markus 907: {
1.92 djm 908: switch (type) {
1.12 markus 909: case KEY_RSA:
910: return "ssh-rsa";
911: case KEY_DSA:
912: return "ssh-dss";
1.87 djm 913: case KEY_RSA_CERT_V00:
914: return "ssh-rsa-cert-v00@openssh.com";
915: case KEY_DSA_CERT_V00:
916: return "ssh-dss-cert-v00@openssh.com";
1.83 djm 917: case KEY_RSA_CERT:
1.87 djm 918: return "ssh-rsa-cert-v01@openssh.com";
1.83 djm 919: case KEY_DSA_CERT:
1.87 djm 920: return "ssh-dss-cert-v01@openssh.com";
1.92 djm 921: case KEY_ECDSA:
922: switch (nid) {
923: case NID_X9_62_prime256v1:
924: return "ecdsa-sha2-nistp256";
925: case NID_secp384r1:
926: return "ecdsa-sha2-nistp384";
927: case NID_secp521r1:
928: return "ecdsa-sha2-nistp521";
929: default:
930: break;
931: }
932: break;
933: case KEY_ECDSA_CERT:
934: switch (nid) {
935: case NID_X9_62_prime256v1:
936: return "ecdsa-sha2-nistp256-cert-v01@openssh.com";
937: case NID_secp384r1:
938: return "ecdsa-sha2-nistp384-cert-v01@openssh.com";
939: case NID_secp521r1:
940: return "ecdsa-sha2-nistp521-cert-v01@openssh.com";
941: default:
942: break;
943: }
944: break;
1.12 markus 945: }
946: return "ssh-unknown";
947: }
1.45 deraadt 948:
1.92 djm 949: const char *
950: key_ssh_name(const Key *k)
951: {
952: return key_ssh_name_from_type_nid(k->type, k->ecdsa_nid);
953: }
954:
955: const char *
956: key_ssh_name_plain(const Key *k)
957: {
958: return key_ssh_name_from_type_nid(key_type_plain(k->type),
959: k->ecdsa_nid);
960: }
961:
1.12 markus 962: u_int
1.55 jakob 963: key_size(const Key *k)
1.35 deraadt 964: {
1.10 markus 965: switch (k->type) {
1.12 markus 966: case KEY_RSA1:
1.10 markus 967: case KEY_RSA:
1.87 djm 968: case KEY_RSA_CERT_V00:
1.83 djm 969: case KEY_RSA_CERT:
1.10 markus 970: return BN_num_bits(k->rsa->n);
971: case KEY_DSA:
1.87 djm 972: case KEY_DSA_CERT_V00:
1.83 djm 973: case KEY_DSA_CERT:
1.10 markus 974: return BN_num_bits(k->dsa->p);
1.92 djm 975: case KEY_ECDSA:
976: case KEY_ECDSA_CERT:
1.93 ! djm 977: return key_curve_nid_to_bits(k->ecdsa_nid);
1.10 markus 978: }
979: return 0;
1.12 markus 980: }
981:
1.27 itojun 982: static RSA *
1.13 markus 983: rsa_generate_private_key(u_int bits)
1.12 markus 984: {
1.17 stevesk 985: RSA *private;
1.61 deraadt 986:
1.81 markus 987: private = RSA_generate_key(bits, RSA_F4, NULL, NULL);
1.17 stevesk 988: if (private == NULL)
989: fatal("rsa_generate_private_key: key generation failed.");
990: return private;
1.12 markus 991: }
992:
1.27 itojun 993: static DSA*
1.13 markus 994: dsa_generate_private_key(u_int bits)
1.12 markus 995: {
996: DSA *private = DSA_generate_parameters(bits, NULL, 0, NULL, NULL, NULL, NULL);
1.61 deraadt 997:
1.12 markus 998: if (private == NULL)
999: fatal("dsa_generate_private_key: DSA_generate_parameters failed");
1000: if (!DSA_generate_key(private))
1.17 stevesk 1001: fatal("dsa_generate_private_key: DSA_generate_key failed.");
1002: if (private == NULL)
1003: fatal("dsa_generate_private_key: NULL.");
1.12 markus 1004: return private;
1005: }
1006:
1.92 djm 1007: int
1008: key_ecdsa_bits_to_nid(int bits)
1009: {
1010: switch (bits) {
1011: case 256:
1012: return NID_X9_62_prime256v1;
1013: case 384:
1014: return NID_secp384r1;
1015: case 521:
1016: return NID_secp521r1;
1017: default:
1018: return -1;
1019: }
1020: }
1021:
1022: /*
1023: * This is horrid, but OpenSSL's PEM_read_PrivateKey seems not to restore
1024: * the EC_GROUP nid when loading a key...
1025: */
1026: int
1027: key_ecdsa_group_to_nid(const EC_GROUP *g)
1028: {
1029: EC_GROUP *eg;
1030: int nids[] = {
1031: NID_X9_62_prime256v1,
1032: NID_secp384r1,
1033: NID_secp521r1,
1034: -1
1035: };
1036: u_int i;
1037: BN_CTX *bnctx;
1038:
1039: if ((bnctx = BN_CTX_new()) == NULL)
1040: fatal("%s: BN_CTX_new() failed", __func__);
1041: for (i = 0; nids[i] != -1; i++) {
1042: if ((eg = EC_GROUP_new_by_curve_name(nids[i])) == NULL)
1043: fatal("%s: EC_GROUP_new_by_curve_name failed",
1044: __func__);
1045: if (EC_GROUP_cmp(g, eg, bnctx) == 0) {
1046: EC_GROUP_free(eg);
1047: break;
1048: }
1049: EC_GROUP_free(eg);
1050: }
1051: BN_CTX_free(bnctx);
1052: debug3("%s: nid = %d", __func__, nids[i]);
1053: return nids[i];
1054: }
1055:
1056: static EC_KEY*
1057: ecdsa_generate_private_key(u_int bits, int *nid)
1058: {
1059: EC_KEY *private;
1060:
1061: if ((*nid = key_ecdsa_bits_to_nid(bits)) == -1)
1062: fatal("%s: invalid key length", __func__);
1063: if ((private = EC_KEY_new_by_curve_name(*nid)) == NULL)
1064: fatal("%s: EC_KEY_new_by_curve_name failed", __func__);
1065: if (EC_KEY_generate_key(private) != 1)
1066: fatal("%s: EC_KEY_generate_key failed", __func__);
1067: return private;
1068: }
1069:
1.12 markus 1070: Key *
1.13 markus 1071: key_generate(int type, u_int bits)
1.12 markus 1072: {
1073: Key *k = key_new(KEY_UNSPEC);
1074: switch (type) {
1.17 stevesk 1075: case KEY_DSA:
1.12 markus 1076: k->dsa = dsa_generate_private_key(bits);
1077: break;
1.92 djm 1078: case KEY_ECDSA:
1079: k->ecdsa = ecdsa_generate_private_key(bits, &k->ecdsa_nid);
1080: break;
1.12 markus 1081: case KEY_RSA:
1082: case KEY_RSA1:
1083: k->rsa = rsa_generate_private_key(bits);
1084: break;
1.87 djm 1085: case KEY_RSA_CERT_V00:
1086: case KEY_DSA_CERT_V00:
1.83 djm 1087: case KEY_RSA_CERT:
1088: case KEY_DSA_CERT:
1089: fatal("key_generate: cert keys cannot be generated directly");
1.12 markus 1090: default:
1.17 stevesk 1091: fatal("key_generate: unknown type %d", type);
1.12 markus 1092: }
1.17 stevesk 1093: k->type = type;
1.12 markus 1094: return k;
1095: }
1096:
1.83 djm 1097: void
1098: key_cert_copy(const Key *from_key, struct Key *to_key)
1099: {
1100: u_int i;
1101: const struct KeyCert *from;
1102: struct KeyCert *to;
1103:
1104: if (to_key->cert != NULL) {
1105: cert_free(to_key->cert);
1106: to_key->cert = NULL;
1107: }
1108:
1109: if ((from = from_key->cert) == NULL)
1110: return;
1111:
1112: to = to_key->cert = cert_new();
1113:
1114: buffer_append(&to->certblob, buffer_ptr(&from->certblob),
1115: buffer_len(&from->certblob));
1116:
1.87 djm 1117: buffer_append(&to->critical,
1118: buffer_ptr(&from->critical), buffer_len(&from->critical));
1119: buffer_append(&to->extensions,
1120: buffer_ptr(&from->extensions), buffer_len(&from->extensions));
1.83 djm 1121:
1.87 djm 1122: to->serial = from->serial;
1.83 djm 1123: to->type = from->type;
1124: to->key_id = from->key_id == NULL ? NULL : xstrdup(from->key_id);
1125: to->valid_after = from->valid_after;
1126: to->valid_before = from->valid_before;
1127: to->signature_key = from->signature_key == NULL ?
1128: NULL : key_from_private(from->signature_key);
1129:
1130: to->nprincipals = from->nprincipals;
1131: if (to->nprincipals > CERT_MAX_PRINCIPALS)
1132: fatal("%s: nprincipals (%u) > CERT_MAX_PRINCIPALS (%u)",
1133: __func__, to->nprincipals, CERT_MAX_PRINCIPALS);
1134: if (to->nprincipals > 0) {
1135: to->principals = xcalloc(from->nprincipals,
1136: sizeof(*to->principals));
1137: for (i = 0; i < to->nprincipals; i++)
1138: to->principals[i] = xstrdup(from->principals[i]);
1139: }
1140: }
1141:
1.12 markus 1142: Key *
1.55 jakob 1143: key_from_private(const Key *k)
1.12 markus 1144: {
1145: Key *n = NULL;
1146: switch (k->type) {
1.17 stevesk 1147: case KEY_DSA:
1.87 djm 1148: case KEY_DSA_CERT_V00:
1.83 djm 1149: case KEY_DSA_CERT:
1.12 markus 1150: n = key_new(k->type);
1.68 markus 1151: if ((BN_copy(n->dsa->p, k->dsa->p) == NULL) ||
1152: (BN_copy(n->dsa->q, k->dsa->q) == NULL) ||
1153: (BN_copy(n->dsa->g, k->dsa->g) == NULL) ||
1154: (BN_copy(n->dsa->pub_key, k->dsa->pub_key) == NULL))
1155: fatal("key_from_private: BN_copy failed");
1.12 markus 1156: break;
1.92 djm 1157: case KEY_ECDSA:
1158: case KEY_ECDSA_CERT:
1159: n = key_new(k->type);
1160: n->ecdsa_nid = k->ecdsa_nid;
1161: if ((n->ecdsa = EC_KEY_new_by_curve_name(k->ecdsa_nid)) == NULL)
1162: fatal("%s: EC_KEY_new_by_curve_name failed", __func__);
1163: if (EC_KEY_set_public_key(n->ecdsa,
1164: EC_KEY_get0_public_key(k->ecdsa)) != 1)
1165: fatal("%s: EC_KEY_set_public_key failed", __func__);
1166: break;
1.12 markus 1167: case KEY_RSA:
1168: case KEY_RSA1:
1.87 djm 1169: case KEY_RSA_CERT_V00:
1.83 djm 1170: case KEY_RSA_CERT:
1.12 markus 1171: n = key_new(k->type);
1.68 markus 1172: if ((BN_copy(n->rsa->n, k->rsa->n) == NULL) ||
1173: (BN_copy(n->rsa->e, k->rsa->e) == NULL))
1174: fatal("key_from_private: BN_copy failed");
1.12 markus 1175: break;
1176: default:
1.17 stevesk 1177: fatal("key_from_private: unknown type %d", k->type);
1.12 markus 1178: break;
1179: }
1.83 djm 1180: if (key_is_cert(k))
1181: key_cert_copy(k, n);
1.12 markus 1182: return n;
1183: }
1184:
1185: int
1186: key_type_from_name(char *name)
1187: {
1.35 deraadt 1188: if (strcmp(name, "rsa1") == 0) {
1.12 markus 1189: return KEY_RSA1;
1.35 deraadt 1190: } else if (strcmp(name, "rsa") == 0) {
1.12 markus 1191: return KEY_RSA;
1.35 deraadt 1192: } else if (strcmp(name, "dsa") == 0) {
1.12 markus 1193: return KEY_DSA;
1.35 deraadt 1194: } else if (strcmp(name, "ssh-rsa") == 0) {
1.12 markus 1195: return KEY_RSA;
1.35 deraadt 1196: } else if (strcmp(name, "ssh-dss") == 0) {
1.12 markus 1197: return KEY_DSA;
1.92 djm 1198: } else if (strcmp(name, "ecdsa") == 0 ||
1199: strcmp(name, "ecdsa-sha2-nistp256") == 0 ||
1200: strcmp(name, "ecdsa-sha2-nistp384") == 0 ||
1201: strcmp(name, "ecdsa-sha2-nistp521") == 0) {
1202: return KEY_ECDSA;
1.83 djm 1203: } else if (strcmp(name, "ssh-rsa-cert-v00@openssh.com") == 0) {
1.87 djm 1204: return KEY_RSA_CERT_V00;
1205: } else if (strcmp(name, "ssh-dss-cert-v00@openssh.com") == 0) {
1206: return KEY_DSA_CERT_V00;
1207: } else if (strcmp(name, "ssh-rsa-cert-v01@openssh.com") == 0) {
1.83 djm 1208: return KEY_RSA_CERT;
1.87 djm 1209: } else if (strcmp(name, "ssh-dss-cert-v01@openssh.com") == 0) {
1.83 djm 1210: return KEY_DSA_CERT;
1.92 djm 1211: } else if (strcmp(name, "ecdsa-sha2-nistp256-cert-v01@openssh.com") == 0 ||
1212: strcmp(name, "ecdsa-sha2-nistp384-cert-v01@openssh.com") == 0 ||
1213: strcmp(name, "ecdsa-sha2-nistp521-cert-v01@openssh.com") == 0)
1214: return KEY_ECDSA_CERT;
1215:
1.18 markus 1216: debug2("key_type_from_name: unknown key type '%s'", name);
1.12 markus 1217: return KEY_UNSPEC;
1.25 markus 1218: }
1219:
1220: int
1.92 djm 1221: key_ecdsa_nid_from_name(const char *name)
1222: {
1223: if (strcmp(name, "ecdsa-sha2-nistp256") == 0 ||
1224: strcmp(name, "ecdsa-sha2-nistp256-cert-v01@openssh.com") == 0)
1225: return NID_X9_62_prime256v1;
1226: if (strcmp(name, "ecdsa-sha2-nistp384") == 0 ||
1227: strcmp(name, "ecdsa-sha2-nistp384-cert-v01@openssh.com") == 0)
1228: return NID_secp384r1;
1229: if (strcmp(name, "ecdsa-sha2-nistp521") == 0 ||
1230: strcmp(name, "ecdsa-sha2-nistp521-cert-v01@openssh.com") == 0)
1231: return NID_secp521r1;
1232:
1233: debug2("%s: unknown/non-ECDSA key type '%s'", __func__, name);
1234: return -1;
1235: }
1236:
1237: int
1.25 markus 1238: key_names_valid2(const char *names)
1239: {
1240: char *s, *cp, *p;
1241:
1242: if (names == NULL || strcmp(names, "") == 0)
1243: return 0;
1244: s = cp = xstrdup(names);
1245: for ((p = strsep(&cp, ",")); p && *p != '\0';
1.36 deraadt 1246: (p = strsep(&cp, ","))) {
1.25 markus 1247: switch (key_type_from_name(p)) {
1248: case KEY_RSA1:
1249: case KEY_UNSPEC:
1250: xfree(s);
1251: return 0;
1252: }
1253: }
1254: debug3("key names ok: [%s]", names);
1255: xfree(s);
1256: return 1;
1.12 markus 1257: }
1258:
1.83 djm 1259: static int
1260: cert_parse(Buffer *b, Key *key, const u_char *blob, u_int blen)
1261: {
1.87 djm 1262: u_char *principals, *critical, *exts, *sig_key, *sig;
1263: u_int signed_len, plen, clen, sklen, slen, kidlen, elen;
1.83 djm 1264: Buffer tmp;
1265: char *principal;
1266: int ret = -1;
1.87 djm 1267: int v00 = key->type == KEY_DSA_CERT_V00 ||
1268: key->type == KEY_RSA_CERT_V00;
1.83 djm 1269:
1270: buffer_init(&tmp);
1271:
1272: /* Copy the entire key blob for verification and later serialisation */
1273: buffer_append(&key->cert->certblob, blob, blen);
1274:
1.87 djm 1275: elen = 0; /* Not touched for v00 certs */
1276: principals = exts = critical = sig_key = sig = NULL;
1277: if ((!v00 && buffer_get_int64_ret(&key->cert->serial, b) != 0) ||
1278: buffer_get_int_ret(&key->cert->type, b) != 0 ||
1.91 djm 1279: (key->cert->key_id = buffer_get_cstring_ret(b, &kidlen)) == NULL ||
1.83 djm 1280: (principals = buffer_get_string_ret(b, &plen)) == NULL ||
1281: buffer_get_int64_ret(&key->cert->valid_after, b) != 0 ||
1282: buffer_get_int64_ret(&key->cert->valid_before, b) != 0 ||
1.87 djm 1283: (critical = buffer_get_string_ret(b, &clen)) == NULL ||
1284: (!v00 && (exts = buffer_get_string_ret(b, &elen)) == NULL) ||
1285: (v00 && buffer_get_string_ptr_ret(b, NULL) == NULL) || /* nonce */
1286: buffer_get_string_ptr_ret(b, NULL) == NULL || /* reserved */
1.83 djm 1287: (sig_key = buffer_get_string_ret(b, &sklen)) == NULL) {
1288: error("%s: parse error", __func__);
1289: goto out;
1290: }
1291:
1.84 djm 1292: if (kidlen != strlen(key->cert->key_id)) {
1293: error("%s: key ID contains \\0 character", __func__);
1294: goto out;
1295: }
1296:
1.83 djm 1297: /* Signature is left in the buffer so we can calculate this length */
1298: signed_len = buffer_len(&key->cert->certblob) - buffer_len(b);
1299:
1300: if ((sig = buffer_get_string_ret(b, &slen)) == NULL) {
1301: error("%s: parse error", __func__);
1302: goto out;
1303: }
1304:
1305: if (key->cert->type != SSH2_CERT_TYPE_USER &&
1306: key->cert->type != SSH2_CERT_TYPE_HOST) {
1307: error("Unknown certificate type %u", key->cert->type);
1308: goto out;
1309: }
1310:
1311: buffer_append(&tmp, principals, plen);
1312: while (buffer_len(&tmp) > 0) {
1313: if (key->cert->nprincipals >= CERT_MAX_PRINCIPALS) {
1.84 djm 1314: error("%s: Too many principals", __func__);
1.83 djm 1315: goto out;
1316: }
1.91 djm 1317: if ((principal = buffer_get_cstring_ret(&tmp, &plen)) == NULL) {
1.84 djm 1318: error("%s: Principals data invalid", __func__);
1319: goto out;
1320: }
1.83 djm 1321: key->cert->principals = xrealloc(key->cert->principals,
1322: key->cert->nprincipals + 1, sizeof(*key->cert->principals));
1323: key->cert->principals[key->cert->nprincipals++] = principal;
1324: }
1325:
1326: buffer_clear(&tmp);
1327:
1.87 djm 1328: buffer_append(&key->cert->critical, critical, clen);
1329: buffer_append(&tmp, critical, clen);
1.83 djm 1330: /* validate structure */
1331: while (buffer_len(&tmp) != 0) {
1.85 djm 1332: if (buffer_get_string_ptr_ret(&tmp, NULL) == NULL ||
1333: buffer_get_string_ptr_ret(&tmp, NULL) == NULL) {
1.87 djm 1334: error("%s: critical option data invalid", __func__);
1335: goto out;
1336: }
1337: }
1338: buffer_clear(&tmp);
1339:
1340: buffer_append(&key->cert->extensions, exts, elen);
1341: buffer_append(&tmp, exts, elen);
1342: /* validate structure */
1343: while (buffer_len(&tmp) != 0) {
1344: if (buffer_get_string_ptr_ret(&tmp, NULL) == NULL ||
1345: buffer_get_string_ptr_ret(&tmp, NULL) == NULL) {
1346: error("%s: extension data invalid", __func__);
1.83 djm 1347: goto out;
1348: }
1349: }
1350: buffer_clear(&tmp);
1351:
1352: if ((key->cert->signature_key = key_from_blob(sig_key,
1353: sklen)) == NULL) {
1.84 djm 1354: error("%s: Signature key invalid", __func__);
1.83 djm 1355: goto out;
1356: }
1357: if (key->cert->signature_key->type != KEY_RSA &&
1.92 djm 1358: key->cert->signature_key->type != KEY_DSA &&
1359: key->cert->signature_key->type != KEY_ECDSA) {
1.84 djm 1360: error("%s: Invalid signature key type %s (%d)", __func__,
1.83 djm 1361: key_type(key->cert->signature_key),
1362: key->cert->signature_key->type);
1363: goto out;
1364: }
1365:
1366: switch (key_verify(key->cert->signature_key, sig, slen,
1367: buffer_ptr(&key->cert->certblob), signed_len)) {
1368: case 1:
1.84 djm 1369: ret = 0;
1.83 djm 1370: break; /* Good signature */
1371: case 0:
1.84 djm 1372: error("%s: Invalid signature on certificate", __func__);
1.83 djm 1373: goto out;
1374: case -1:
1.84 djm 1375: error("%s: Certificate signature verification failed",
1376: __func__);
1.83 djm 1377: goto out;
1378: }
1379:
1380: out:
1381: buffer_free(&tmp);
1382: if (principals != NULL)
1383: xfree(principals);
1.87 djm 1384: if (critical != NULL)
1385: xfree(critical);
1386: if (exts != NULL)
1387: xfree(exts);
1.83 djm 1388: if (sig_key != NULL)
1389: xfree(sig_key);
1390: if (sig != NULL)
1391: xfree(sig);
1392: return ret;
1393: }
1394:
1.12 markus 1395: Key *
1.55 jakob 1396: key_from_blob(const u_char *blob, u_int blen)
1.12 markus 1397: {
1398: Buffer b;
1.92 djm 1399: int rlen, type, nid = -1;
1400: char *ktype = NULL, *curve = NULL;
1.12 markus 1401: Key *key = NULL;
1.92 djm 1402: EC_POINT *q = NULL;
1.12 markus 1403:
1404: #ifdef DEBUG_PK
1405: dump_base64(stderr, blob, blen);
1406: #endif
1407: buffer_init(&b);
1408: buffer_append(&b, blob, blen);
1.91 djm 1409: if ((ktype = buffer_get_cstring_ret(&b, NULL)) == NULL) {
1.57 djm 1410: error("key_from_blob: can't read key type");
1411: goto out;
1412: }
1413:
1.12 markus 1414: type = key_type_from_name(ktype);
1.92 djm 1415: if (key_type_plain(type) == KEY_ECDSA)
1416: nid = key_ecdsa_nid_from_name(ktype);
1.12 markus 1417:
1.35 deraadt 1418: switch (type) {
1.87 djm 1419: case KEY_RSA_CERT:
1420: (void)buffer_get_string_ptr_ret(&b, NULL); /* Skip nonce */
1421: /* FALLTHROUGH */
1.12 markus 1422: case KEY_RSA:
1.87 djm 1423: case KEY_RSA_CERT_V00:
1.12 markus 1424: key = key_new(type);
1.57 djm 1425: if (buffer_get_bignum2_ret(&b, key->rsa->e) == -1 ||
1426: buffer_get_bignum2_ret(&b, key->rsa->n) == -1) {
1427: error("key_from_blob: can't read rsa key");
1.83 djm 1428: badkey:
1.57 djm 1429: key_free(key);
1430: key = NULL;
1431: goto out;
1432: }
1.12 markus 1433: #ifdef DEBUG_PK
1434: RSA_print_fp(stderr, key->rsa, 8);
1435: #endif
1436: break;
1.87 djm 1437: case KEY_DSA_CERT:
1438: (void)buffer_get_string_ptr_ret(&b, NULL); /* Skip nonce */
1439: /* FALLTHROUGH */
1.12 markus 1440: case KEY_DSA:
1.87 djm 1441: case KEY_DSA_CERT_V00:
1.12 markus 1442: key = key_new(type);
1.57 djm 1443: if (buffer_get_bignum2_ret(&b, key->dsa->p) == -1 ||
1444: buffer_get_bignum2_ret(&b, key->dsa->q) == -1 ||
1445: buffer_get_bignum2_ret(&b, key->dsa->g) == -1 ||
1446: buffer_get_bignum2_ret(&b, key->dsa->pub_key) == -1) {
1447: error("key_from_blob: can't read dsa key");
1.83 djm 1448: goto badkey;
1.57 djm 1449: }
1.12 markus 1450: #ifdef DEBUG_PK
1451: DSA_print_fp(stderr, key->dsa, 8);
1452: #endif
1453: break;
1.92 djm 1454: case KEY_ECDSA_CERT:
1455: (void)buffer_get_string_ptr_ret(&b, NULL); /* Skip nonce */
1456: /* FALLTHROUGH */
1457: case KEY_ECDSA:
1458: key = key_new(type);
1459: key->ecdsa_nid = nid;
1460: if ((curve = buffer_get_string_ret(&b, NULL)) == NULL) {
1461: error("key_from_blob: can't read ecdsa curve");
1462: goto badkey;
1463: }
1464: if (key->ecdsa_nid != key_curve_name_to_nid(curve)) {
1465: error("key_from_blob: ecdsa curve doesn't match type");
1466: goto badkey;
1467: }
1468: if (key->ecdsa != NULL)
1469: EC_KEY_free(key->ecdsa);
1470: if ((key->ecdsa = EC_KEY_new_by_curve_name(key->ecdsa_nid))
1471: == NULL)
1472: fatal("key_from_blob: EC_KEY_new_by_curve_name failed");
1473: if ((q = EC_POINT_new(EC_KEY_get0_group(key->ecdsa))) == NULL)
1474: fatal("key_from_blob: EC_POINT_new failed");
1475: if (buffer_get_ecpoint_ret(&b, EC_KEY_get0_group(key->ecdsa),
1476: q) == -1) {
1477: error("key_from_blob: can't read ecdsa key point");
1478: goto badkey;
1479: }
1480: if (key_ec_validate_public(EC_KEY_get0_group(key->ecdsa),
1481: q) != 0)
1482: goto badkey;
1483: if (EC_KEY_set_public_key(key->ecdsa, q) != 1)
1484: fatal("key_from_blob: EC_KEY_set_public_key failed");
1485: #ifdef DEBUG_PK
1486: key_dump_ec_point(EC_KEY_get0_group(key->ecdsa), q);
1487: #endif
1488: break;
1.12 markus 1489: case KEY_UNSPEC:
1490: key = key_new(type);
1491: break;
1492: default:
1493: error("key_from_blob: cannot handle type %s", ktype);
1.57 djm 1494: goto out;
1.12 markus 1495: }
1.83 djm 1496: if (key_is_cert(key) && cert_parse(&b, key, blob, blen) == -1) {
1497: error("key_from_blob: can't parse cert data");
1498: goto badkey;
1499: }
1.12 markus 1500: rlen = buffer_len(&b);
1501: if (key != NULL && rlen != 0)
1502: error("key_from_blob: remaining bytes in key blob %d", rlen);
1.57 djm 1503: out:
1504: if (ktype != NULL)
1505: xfree(ktype);
1.92 djm 1506: if (curve != NULL)
1507: xfree(curve);
1508: if (q != NULL)
1509: EC_POINT_free(q);
1.12 markus 1510: buffer_free(&b);
1511: return key;
1512: }
1513:
1514: int
1.55 jakob 1515: key_to_blob(const Key *key, u_char **blobp, u_int *lenp)
1.12 markus 1516: {
1517: Buffer b;
1518: int len;
1519:
1520: if (key == NULL) {
1521: error("key_to_blob: key == NULL");
1522: return 0;
1523: }
1524: buffer_init(&b);
1.35 deraadt 1525: switch (key->type) {
1.87 djm 1526: case KEY_DSA_CERT_V00:
1527: case KEY_RSA_CERT_V00:
1.83 djm 1528: case KEY_DSA_CERT:
1.92 djm 1529: case KEY_ECDSA_CERT:
1.83 djm 1530: case KEY_RSA_CERT:
1531: /* Use the existing blob */
1532: buffer_append(&b, buffer_ptr(&key->cert->certblob),
1533: buffer_len(&key->cert->certblob));
1534: break;
1.12 markus 1535: case KEY_DSA:
1536: buffer_put_cstring(&b, key_ssh_name(key));
1537: buffer_put_bignum2(&b, key->dsa->p);
1538: buffer_put_bignum2(&b, key->dsa->q);
1539: buffer_put_bignum2(&b, key->dsa->g);
1540: buffer_put_bignum2(&b, key->dsa->pub_key);
1541: break;
1.92 djm 1542: case KEY_ECDSA:
1543: buffer_put_cstring(&b, key_ssh_name(key));
1544: buffer_put_cstring(&b, key_curve_nid_to_name(key->ecdsa_nid));
1545: buffer_put_ecpoint(&b, EC_KEY_get0_group(key->ecdsa),
1546: EC_KEY_get0_public_key(key->ecdsa));
1547: break;
1.12 markus 1548: case KEY_RSA:
1549: buffer_put_cstring(&b, key_ssh_name(key));
1.14 markus 1550: buffer_put_bignum2(&b, key->rsa->e);
1.12 markus 1551: buffer_put_bignum2(&b, key->rsa->n);
1552: break;
1553: default:
1.31 markus 1554: error("key_to_blob: unsupported key type %d", key->type);
1555: buffer_free(&b);
1556: return 0;
1.12 markus 1557: }
1558: len = buffer_len(&b);
1.48 markus 1559: if (lenp != NULL)
1560: *lenp = len;
1561: if (blobp != NULL) {
1562: *blobp = xmalloc(len);
1563: memcpy(*blobp, buffer_ptr(&b), len);
1564: }
1.12 markus 1565: memset(buffer_ptr(&b), 0, len);
1566: buffer_free(&b);
1567: return len;
1568: }
1569:
1570: int
1571: key_sign(
1.55 jakob 1572: const Key *key,
1.40 markus 1573: u_char **sigp, u_int *lenp,
1.55 jakob 1574: const u_char *data, u_int datalen)
1.12 markus 1575: {
1.35 deraadt 1576: switch (key->type) {
1.87 djm 1577: case KEY_DSA_CERT_V00:
1.83 djm 1578: case KEY_DSA_CERT:
1.12 markus 1579: case KEY_DSA:
1580: return ssh_dss_sign(key, sigp, lenp, data, datalen);
1.92 djm 1581: case KEY_ECDSA_CERT:
1582: case KEY_ECDSA:
1583: return ssh_ecdsa_sign(key, sigp, lenp, data, datalen);
1.87 djm 1584: case KEY_RSA_CERT_V00:
1.83 djm 1585: case KEY_RSA_CERT:
1.12 markus 1586: case KEY_RSA:
1587: return ssh_rsa_sign(key, sigp, lenp, data, datalen);
1588: default:
1.56 markus 1589: error("key_sign: invalid key type %d", key->type);
1.12 markus 1590: return -1;
1591: }
1592: }
1593:
1.44 markus 1594: /*
1595: * key_verify returns 1 for a correct signature, 0 for an incorrect signature
1596: * and -1 on error.
1597: */
1.12 markus 1598: int
1599: key_verify(
1.55 jakob 1600: const Key *key,
1601: const u_char *signature, u_int signaturelen,
1602: const u_char *data, u_int datalen)
1.12 markus 1603: {
1.26 markus 1604: if (signaturelen == 0)
1605: return -1;
1606:
1.35 deraadt 1607: switch (key->type) {
1.87 djm 1608: case KEY_DSA_CERT_V00:
1.83 djm 1609: case KEY_DSA_CERT:
1.12 markus 1610: case KEY_DSA:
1611: return ssh_dss_verify(key, signature, signaturelen, data, datalen);
1.92 djm 1612: case KEY_ECDSA_CERT:
1613: case KEY_ECDSA:
1614: return ssh_ecdsa_verify(key, signature, signaturelen, data, datalen);
1.87 djm 1615: case KEY_RSA_CERT_V00:
1.83 djm 1616: case KEY_RSA_CERT:
1.12 markus 1617: case KEY_RSA:
1618: return ssh_rsa_verify(key, signature, signaturelen, data, datalen);
1619: default:
1.56 markus 1620: error("key_verify: invalid key type %d", key->type);
1.12 markus 1621: return -1;
1622: }
1.42 markus 1623: }
1624:
1625: /* Converts a private to a public key */
1626: Key *
1.55 jakob 1627: key_demote(const Key *k)
1.42 markus 1628: {
1629: Key *pk;
1.43 markus 1630:
1.63 djm 1631: pk = xcalloc(1, sizeof(*pk));
1.42 markus 1632: pk->type = k->type;
1633: pk->flags = k->flags;
1.92 djm 1634: pk->ecdsa_nid = k->ecdsa_nid;
1.42 markus 1635: pk->dsa = NULL;
1.92 djm 1636: pk->ecdsa = NULL;
1.42 markus 1637: pk->rsa = NULL;
1638:
1639: switch (k->type) {
1.87 djm 1640: case KEY_RSA_CERT_V00:
1.83 djm 1641: case KEY_RSA_CERT:
1642: key_cert_copy(k, pk);
1643: /* FALLTHROUGH */
1.42 markus 1644: case KEY_RSA1:
1645: case KEY_RSA:
1646: if ((pk->rsa = RSA_new()) == NULL)
1647: fatal("key_demote: RSA_new failed");
1648: if ((pk->rsa->e = BN_dup(k->rsa->e)) == NULL)
1649: fatal("key_demote: BN_dup failed");
1650: if ((pk->rsa->n = BN_dup(k->rsa->n)) == NULL)
1651: fatal("key_demote: BN_dup failed");
1652: break;
1.87 djm 1653: case KEY_DSA_CERT_V00:
1.83 djm 1654: case KEY_DSA_CERT:
1655: key_cert_copy(k, pk);
1656: /* FALLTHROUGH */
1.42 markus 1657: case KEY_DSA:
1658: if ((pk->dsa = DSA_new()) == NULL)
1659: fatal("key_demote: DSA_new failed");
1660: if ((pk->dsa->p = BN_dup(k->dsa->p)) == NULL)
1661: fatal("key_demote: BN_dup failed");
1662: if ((pk->dsa->q = BN_dup(k->dsa->q)) == NULL)
1663: fatal("key_demote: BN_dup failed");
1664: if ((pk->dsa->g = BN_dup(k->dsa->g)) == NULL)
1665: fatal("key_demote: BN_dup failed");
1666: if ((pk->dsa->pub_key = BN_dup(k->dsa->pub_key)) == NULL)
1667: fatal("key_demote: BN_dup failed");
1668: break;
1.92 djm 1669: case KEY_ECDSA_CERT:
1670: key_cert_copy(k, pk);
1671: /* FALLTHROUGH */
1672: case KEY_ECDSA:
1673: if ((pk->ecdsa = EC_KEY_new_by_curve_name(pk->ecdsa_nid)) == NULL)
1674: fatal("key_demote: EC_KEY_new_by_curve_name failed");
1675: if (EC_KEY_set_public_key(pk->ecdsa,
1676: EC_KEY_get0_public_key(k->ecdsa)) != 1)
1677: fatal("key_demote: EC_KEY_set_public_key failed");
1678: break;
1.42 markus 1679: default:
1680: fatal("key_free: bad key type %d", k->type);
1681: break;
1682: }
1683:
1684: return (pk);
1.83 djm 1685: }
1686:
1687: int
1688: key_is_cert(const Key *k)
1689: {
1.87 djm 1690: if (k == NULL)
1691: return 0;
1692: switch (k->type) {
1693: case KEY_RSA_CERT_V00:
1694: case KEY_DSA_CERT_V00:
1695: case KEY_RSA_CERT:
1696: case KEY_DSA_CERT:
1.92 djm 1697: case KEY_ECDSA_CERT:
1.87 djm 1698: return 1;
1699: default:
1700: return 0;
1701: }
1.83 djm 1702: }
1703:
1704: /* Return the cert-less equivalent to a certified key type */
1705: int
1706: key_type_plain(int type)
1707: {
1708: switch (type) {
1.87 djm 1709: case KEY_RSA_CERT_V00:
1.83 djm 1710: case KEY_RSA_CERT:
1711: return KEY_RSA;
1.87 djm 1712: case KEY_DSA_CERT_V00:
1.83 djm 1713: case KEY_DSA_CERT:
1714: return KEY_DSA;
1.92 djm 1715: case KEY_ECDSA_CERT:
1716: return KEY_ECDSA;
1.83 djm 1717: default:
1718: return type;
1719: }
1720: }
1721:
1722: /* Convert a KEY_RSA or KEY_DSA to their _CERT equivalent */
1723: int
1.87 djm 1724: key_to_certified(Key *k, int legacy)
1.83 djm 1725: {
1726: switch (k->type) {
1727: case KEY_RSA:
1728: k->cert = cert_new();
1.87 djm 1729: k->type = legacy ? KEY_RSA_CERT_V00 : KEY_RSA_CERT;
1.83 djm 1730: return 0;
1731: case KEY_DSA:
1732: k->cert = cert_new();
1.87 djm 1733: k->type = legacy ? KEY_DSA_CERT_V00 : KEY_DSA_CERT;
1.83 djm 1734: return 0;
1.92 djm 1735: case KEY_ECDSA:
1736: k->cert = cert_new();
1737: k->type = KEY_ECDSA_CERT;
1738: return 0;
1.83 djm 1739: default:
1740: error("%s: key has incorrect type %s", __func__, key_type(k));
1741: return -1;
1742: }
1743: }
1744:
1745: /* Convert a KEY_RSA_CERT or KEY_DSA_CERT to their raw key equivalent */
1746: int
1747: key_drop_cert(Key *k)
1748: {
1749: switch (k->type) {
1.87 djm 1750: case KEY_RSA_CERT_V00:
1.83 djm 1751: case KEY_RSA_CERT:
1752: cert_free(k->cert);
1753: k->type = KEY_RSA;
1754: return 0;
1.87 djm 1755: case KEY_DSA_CERT_V00:
1.83 djm 1756: case KEY_DSA_CERT:
1757: cert_free(k->cert);
1758: k->type = KEY_DSA;
1759: return 0;
1.92 djm 1760: case KEY_ECDSA_CERT:
1761: cert_free(k->cert);
1762: k->type = KEY_ECDSA;
1763: return 0;
1.83 djm 1764: default:
1765: error("%s: key has incorrect type %s", __func__, key_type(k));
1766: return -1;
1767: }
1768: }
1769:
1.92 djm 1770: /*
1771: * Sign a KEY_RSA_CERT, KEY_DSA_CERT or KEY_ECDSA_CERT, (re-)generating
1772: * the signed certblob
1773: */
1.83 djm 1774: int
1775: key_certify(Key *k, Key *ca)
1776: {
1777: Buffer principals;
1778: u_char *ca_blob, *sig_blob, nonce[32];
1779: u_int i, ca_len, sig_len;
1780:
1781: if (k->cert == NULL) {
1782: error("%s: key lacks cert info", __func__);
1783: return -1;
1784: }
1785:
1786: if (!key_is_cert(k)) {
1787: error("%s: certificate has unknown type %d", __func__,
1788: k->cert->type);
1789: return -1;
1790: }
1791:
1.92 djm 1792: if (ca->type != KEY_RSA && ca->type != KEY_DSA &&
1793: ca->type != KEY_ECDSA) {
1.83 djm 1794: error("%s: CA key has unsupported type %s", __func__,
1795: key_type(ca));
1796: return -1;
1797: }
1798:
1799: key_to_blob(ca, &ca_blob, &ca_len);
1800:
1801: buffer_clear(&k->cert->certblob);
1802: buffer_put_cstring(&k->cert->certblob, key_ssh_name(k));
1803:
1.87 djm 1804: /* -v01 certs put nonce first */
1.92 djm 1805: if (!key_cert_is_legacy(k)) {
1.87 djm 1806: arc4random_buf(&nonce, sizeof(nonce));
1807: buffer_put_string(&k->cert->certblob, nonce, sizeof(nonce));
1808: }
1809:
1.83 djm 1810: switch (k->type) {
1.87 djm 1811: case KEY_DSA_CERT_V00:
1.83 djm 1812: case KEY_DSA_CERT:
1813: buffer_put_bignum2(&k->cert->certblob, k->dsa->p);
1814: buffer_put_bignum2(&k->cert->certblob, k->dsa->q);
1815: buffer_put_bignum2(&k->cert->certblob, k->dsa->g);
1816: buffer_put_bignum2(&k->cert->certblob, k->dsa->pub_key);
1817: break;
1.92 djm 1818: case KEY_ECDSA_CERT:
1819: buffer_put_cstring(&k->cert->certblob,
1820: key_curve_nid_to_name(k->ecdsa_nid));
1821: buffer_put_ecpoint(&k->cert->certblob,
1822: EC_KEY_get0_group(k->ecdsa),
1823: EC_KEY_get0_public_key(k->ecdsa));
1824: break;
1.87 djm 1825: case KEY_RSA_CERT_V00:
1.83 djm 1826: case KEY_RSA_CERT:
1827: buffer_put_bignum2(&k->cert->certblob, k->rsa->e);
1828: buffer_put_bignum2(&k->cert->certblob, k->rsa->n);
1829: break;
1830: default:
1831: error("%s: key has incorrect type %s", __func__, key_type(k));
1832: buffer_clear(&k->cert->certblob);
1833: xfree(ca_blob);
1834: return -1;
1835: }
1836:
1.87 djm 1837: /* -v01 certs have a serial number next */
1.92 djm 1838: if (!key_cert_is_legacy(k))
1.87 djm 1839: buffer_put_int64(&k->cert->certblob, k->cert->serial);
1840:
1.83 djm 1841: buffer_put_int(&k->cert->certblob, k->cert->type);
1842: buffer_put_cstring(&k->cert->certblob, k->cert->key_id);
1843:
1844: buffer_init(&principals);
1845: for (i = 0; i < k->cert->nprincipals; i++)
1846: buffer_put_cstring(&principals, k->cert->principals[i]);
1847: buffer_put_string(&k->cert->certblob, buffer_ptr(&principals),
1848: buffer_len(&principals));
1849: buffer_free(&principals);
1850:
1851: buffer_put_int64(&k->cert->certblob, k->cert->valid_after);
1852: buffer_put_int64(&k->cert->certblob, k->cert->valid_before);
1853: buffer_put_string(&k->cert->certblob,
1.87 djm 1854: buffer_ptr(&k->cert->critical), buffer_len(&k->cert->critical));
1855:
1856: /* -v01 certs have non-critical options here */
1.92 djm 1857: if (!key_cert_is_legacy(k)) {
1.87 djm 1858: buffer_put_string(&k->cert->certblob,
1859: buffer_ptr(&k->cert->extensions),
1860: buffer_len(&k->cert->extensions));
1861: }
1862:
1863: /* -v00 certs put the nonce at the end */
1.92 djm 1864: if (key_cert_is_legacy(k))
1.87 djm 1865: buffer_put_string(&k->cert->certblob, nonce, sizeof(nonce));
1.83 djm 1866:
1867: buffer_put_string(&k->cert->certblob, NULL, 0); /* reserved */
1868: buffer_put_string(&k->cert->certblob, ca_blob, ca_len);
1869: xfree(ca_blob);
1870:
1871: /* Sign the whole mess */
1872: if (key_sign(ca, &sig_blob, &sig_len, buffer_ptr(&k->cert->certblob),
1873: buffer_len(&k->cert->certblob)) != 0) {
1874: error("%s: signature operation failed", __func__);
1875: buffer_clear(&k->cert->certblob);
1876: return -1;
1877: }
1878: /* Append signature and we are done */
1879: buffer_put_string(&k->cert->certblob, sig_blob, sig_len);
1880: xfree(sig_blob);
1881:
1882: return 0;
1883: }
1884:
1885: int
1886: key_cert_check_authority(const Key *k, int want_host, int require_principal,
1887: const char *name, const char **reason)
1888: {
1889: u_int i, principal_matches;
1890: time_t now = time(NULL);
1891:
1892: if (want_host) {
1893: if (k->cert->type != SSH2_CERT_TYPE_HOST) {
1894: *reason = "Certificate invalid: not a host certificate";
1895: return -1;
1896: }
1897: } else {
1898: if (k->cert->type != SSH2_CERT_TYPE_USER) {
1899: *reason = "Certificate invalid: not a user certificate";
1900: return -1;
1901: }
1902: }
1903: if (now < 0) {
1904: error("%s: system clock lies before epoch", __func__);
1905: *reason = "Certificate invalid: not yet valid";
1906: return -1;
1907: }
1908: if ((u_int64_t)now < k->cert->valid_after) {
1909: *reason = "Certificate invalid: not yet valid";
1910: return -1;
1911: }
1912: if ((u_int64_t)now >= k->cert->valid_before) {
1913: *reason = "Certificate invalid: expired";
1914: return -1;
1915: }
1916: if (k->cert->nprincipals == 0) {
1917: if (require_principal) {
1918: *reason = "Certificate lacks principal list";
1919: return -1;
1920: }
1.88 djm 1921: } else if (name != NULL) {
1.83 djm 1922: principal_matches = 0;
1923: for (i = 0; i < k->cert->nprincipals; i++) {
1924: if (strcmp(name, k->cert->principals[i]) == 0) {
1925: principal_matches = 1;
1926: break;
1927: }
1928: }
1929: if (!principal_matches) {
1930: *reason = "Certificate invalid: name is not a listed "
1931: "principal";
1932: return -1;
1933: }
1934: }
1935: return 0;
1.87 djm 1936: }
1937:
1938: int
1939: key_cert_is_legacy(Key *k)
1940: {
1941: switch (k->type) {
1942: case KEY_DSA_CERT_V00:
1943: case KEY_RSA_CERT_V00:
1944: return 1;
1945: default:
1946: return 0;
1947: }
1.4 markus 1948: }
1.92 djm 1949:
1.93 ! djm 1950: /* XXX: these are really begging for a table-driven approach */
1.92 djm 1951: int
1952: key_curve_name_to_nid(const char *name)
1953: {
1954: if (strcmp(name, "nistp256") == 0)
1955: return NID_X9_62_prime256v1;
1956: else if (strcmp(name, "nistp384") == 0)
1957: return NID_secp384r1;
1958: else if (strcmp(name, "nistp521") == 0)
1959: return NID_secp521r1;
1960:
1961: debug("%s: unsupported EC curve name \"%.100s\"", __func__, name);
1962: return -1;
1963: }
1964:
1.93 ! djm 1965: u_int
! 1966: key_curve_nid_to_bits(int nid)
! 1967: {
! 1968: switch (nid) {
! 1969: case NID_X9_62_prime256v1:
! 1970: return 256;
! 1971: case NID_secp384r1:
! 1972: return 384;
! 1973: case NID_secp521r1:
! 1974: return 521;
! 1975: default:
! 1976: error("%s: unsupported EC curve nid %d", __func__, nid);
! 1977: return 0;
! 1978: }
! 1979: }
! 1980:
1.92 djm 1981: const char *
1982: key_curve_nid_to_name(int nid)
1983: {
1984: if (nid == NID_X9_62_prime256v1)
1985: return "nistp256";
1986: else if (nid == NID_secp384r1)
1987: return "nistp384";
1988: else if (nid == NID_secp521r1)
1989: return "nistp521";
1990:
1991: error("%s: unsupported EC curve nid %d", __func__, nid);
1992: return NULL;
1.93 ! djm 1993: }
! 1994:
! 1995: const EVP_MD *
! 1996: key_ec_nid_to_evpmd(int nid)
! 1997: {
! 1998: int kbits = key_curve_nid_to_bits(nid);
! 1999:
! 2000: if (kbits == 0)
! 2001: fatal("%s: invalid nid %d", __func__, nid);
! 2002: /* RFC5656 section 6.2.1 */
! 2003: if (kbits <= 256)
! 2004: return EVP_sha256();
! 2005: else if (kbits <= 384)
! 2006: return EVP_sha384();
! 2007: else
! 2008: return EVP_sha512();
1.92 djm 2009: }
2010:
2011: int
2012: key_ec_validate_public(const EC_GROUP *group, const EC_POINT *public)
2013: {
2014: BN_CTX *bnctx;
2015: EC_POINT *nq = NULL;
2016: BIGNUM *order, *x, *y, *tmp;
2017: int ret = -1;
2018:
2019: if ((bnctx = BN_CTX_new()) == NULL)
2020: fatal("%s: BN_CTX_new failed", __func__);
2021: BN_CTX_start(bnctx);
2022:
2023: /*
2024: * We shouldn't ever hit this case because bignum_get_ecpoint()
2025: * refuses to load GF2m points.
2026: */
2027: if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) !=
2028: NID_X9_62_prime_field) {
2029: error("%s: group is not a prime field", __func__);
2030: goto out;
2031: }
2032:
2033: /* Q != infinity */
2034: if (EC_POINT_is_at_infinity(group, public)) {
2035: error("%s: received degenerate public key (infinity)",
2036: __func__);
2037: goto out;
2038: }
2039:
2040: if ((x = BN_CTX_get(bnctx)) == NULL ||
2041: (y = BN_CTX_get(bnctx)) == NULL ||
2042: (order = BN_CTX_get(bnctx)) == NULL ||
2043: (tmp = BN_CTX_get(bnctx)) == NULL)
2044: fatal("%s: BN_CTX_get failed", __func__);
2045:
2046: /* log2(x) > log2(order)/2, log2(y) > log2(order)/2 */
2047: if (EC_GROUP_get_order(group, order, bnctx) != 1)
2048: fatal("%s: EC_GROUP_get_order failed", __func__);
2049: if (EC_POINT_get_affine_coordinates_GFp(group, public,
2050: x, y, bnctx) != 1)
2051: fatal("%s: EC_POINT_get_affine_coordinates_GFp", __func__);
2052: if (BN_num_bits(x) <= BN_num_bits(order) / 2) {
2053: error("%s: public key x coordinate too small: "
2054: "bits(x) = %d, bits(order)/2 = %d", __func__,
2055: BN_num_bits(x), BN_num_bits(order) / 2);
2056: goto out;
2057: }
2058: if (BN_num_bits(y) <= BN_num_bits(order) / 2) {
2059: error("%s: public key y coordinate too small: "
2060: "bits(y) = %d, bits(order)/2 = %d", __func__,
2061: BN_num_bits(x), BN_num_bits(order) / 2);
2062: goto out;
2063: }
2064:
2065: /* nQ == infinity (n == order of subgroup) */
2066: if ((nq = EC_POINT_new(group)) == NULL)
2067: fatal("%s: BN_CTX_tmp failed", __func__);
2068: if (EC_POINT_mul(group, nq, NULL, public, order, bnctx) != 1)
2069: fatal("%s: EC_GROUP_mul failed", __func__);
2070: if (EC_POINT_is_at_infinity(group, nq) != 1) {
2071: error("%s: received degenerate public key (nQ != infinity)",
2072: __func__);
2073: goto out;
2074: }
2075:
2076: /* x < order - 1, y < order - 1 */
2077: if (!BN_sub(tmp, order, BN_value_one()))
2078: fatal("%s: BN_sub failed", __func__);
2079: if (BN_cmp(x, tmp) >= 0) {
2080: error("%s: public key x coordinate >= group order - 1",
2081: __func__);
2082: goto out;
2083: }
2084: if (BN_cmp(y, tmp) >= 0) {
2085: error("%s: public key y coordinate >= group order - 1",
2086: __func__);
2087: goto out;
2088: }
2089: ret = 0;
2090: out:
2091: BN_CTX_free(bnctx);
2092: EC_POINT_free(nq);
2093: return ret;
2094: }
2095:
2096: int
2097: key_ec_validate_private(const EC_KEY *key)
2098: {
2099: BN_CTX *bnctx;
2100: BIGNUM *order, *tmp;
2101: int ret = -1;
2102:
2103: if ((bnctx = BN_CTX_new()) == NULL)
2104: fatal("%s: BN_CTX_new failed", __func__);
2105: BN_CTX_start(bnctx);
2106:
2107: if ((order = BN_CTX_get(bnctx)) == NULL ||
2108: (tmp = BN_CTX_get(bnctx)) == NULL)
2109: fatal("%s: BN_CTX_get failed", __func__);
2110:
2111: /* log2(private) > log2(order)/2 */
2112: if (EC_GROUP_get_order(EC_KEY_get0_group(key), order, bnctx) != 1)
2113: fatal("%s: EC_GROUP_get_order failed", __func__);
2114: if (BN_num_bits(EC_KEY_get0_private_key(key)) <=
2115: BN_num_bits(order) / 2) {
2116: error("%s: private key too small: "
2117: "bits(y) = %d, bits(order)/2 = %d", __func__,
2118: BN_num_bits(EC_KEY_get0_private_key(key)),
2119: BN_num_bits(order) / 2);
2120: goto out;
2121: }
2122:
2123: /* private < order - 1 */
2124: if (!BN_sub(tmp, order, BN_value_one()))
2125: fatal("%s: BN_sub failed", __func__);
2126: if (BN_cmp(EC_KEY_get0_private_key(key), tmp) >= 0) {
2127: error("%s: private key >= group order - 1", __func__);
2128: goto out;
2129: }
2130: ret = 0;
2131: out:
2132: BN_CTX_free(bnctx);
2133: return ret;
2134: }
2135:
2136: #if defined(DEBUG_KEXECDH) || defined(DEBUG_PK)
2137: void
2138: key_dump_ec_point(const EC_GROUP *group, const EC_POINT *point)
2139: {
2140: BIGNUM *x, *y;
2141: BN_CTX *bnctx;
2142:
2143: if (point == NULL) {
2144: fputs("point=(NULL)\n", stderr);
2145: return;
2146: }
2147: if ((bnctx = BN_CTX_new()) == NULL)
2148: fatal("%s: BN_CTX_new failed", __func__);
2149: BN_CTX_start(bnctx);
2150: if ((x = BN_CTX_get(bnctx)) == NULL || (y = BN_CTX_get(bnctx)) == NULL)
2151: fatal("%s: BN_CTX_get failed", __func__);
2152: if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) !=
2153: NID_X9_62_prime_field)
2154: fatal("%s: group is not a prime field", __func__);
2155: if (EC_POINT_get_affine_coordinates_GFp(group, point, x, y, bnctx) != 1)
2156: fatal("%s: EC_POINT_get_affine_coordinates_GFp", __func__);
2157: fputs("x=", stderr);
2158: BN_print_fp(stderr, x);
2159: fputs("\ny=", stderr);
2160: BN_print_fp(stderr, y);
2161: fputs("\n", stderr);
2162: BN_CTX_free(bnctx);
2163: }
2164:
2165: void
2166: key_dump_ec_key(const EC_KEY *key)
2167: {
2168: const BIGNUM *exponent;
2169:
2170: key_dump_ec_point(EC_KEY_get0_group(key), EC_KEY_get0_public_key(key));
2171: fputs("exponent=", stderr);
2172: if ((exponent = EC_KEY_get0_private_key(key)) == NULL)
2173: fputs("(NULL)", stderr);
2174: else
2175: BN_print_fp(stderr, EC_KEY_get0_private_key(key));
2176: fputs("\n", stderr);
2177: }
2178: #endif /* defined(DEBUG_KEXECDH) || defined(DEBUG_PK) */
2179:
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