Annotation of src/usr.bin/ssh/key.c, Revision 1.103
1.103 ! djm 1: /* $OpenBSD: key.c,v 1.102 2013/05/10 04:08:01 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:
1.100 djm 54: static int to_blob(const Key *, u_char **, u_int *, int);
55:
1.83 djm 56: static struct KeyCert *
57: cert_new(void)
58: {
59: struct KeyCert *cert;
60:
61: cert = xcalloc(1, sizeof(*cert));
62: buffer_init(&cert->certblob);
1.87 djm 63: buffer_init(&cert->critical);
64: buffer_init(&cert->extensions);
1.83 djm 65: cert->key_id = NULL;
66: cert->principals = NULL;
67: cert->signature_key = NULL;
68: return cert;
69: }
1.1 markus 70:
71: Key *
72: key_new(int type)
73: {
74: Key *k;
75: RSA *rsa;
76: DSA *dsa;
1.63 djm 77: k = xcalloc(1, sizeof(*k));
1.1 markus 78: k->type = type;
1.92 djm 79: k->ecdsa = NULL;
80: k->ecdsa_nid = -1;
1.3 markus 81: k->dsa = NULL;
82: k->rsa = NULL;
1.83 djm 83: k->cert = NULL;
1.1 markus 84: switch (k->type) {
1.12 markus 85: case KEY_RSA1:
1.1 markus 86: case KEY_RSA:
1.87 djm 87: case KEY_RSA_CERT_V00:
1.83 djm 88: case KEY_RSA_CERT:
1.38 markus 89: if ((rsa = RSA_new()) == NULL)
90: fatal("key_new: RSA_new failed");
91: if ((rsa->n = BN_new()) == NULL)
92: fatal("key_new: BN_new failed");
93: if ((rsa->e = BN_new()) == NULL)
94: fatal("key_new: BN_new failed");
1.1 markus 95: k->rsa = rsa;
96: break;
97: case KEY_DSA:
1.87 djm 98: case KEY_DSA_CERT_V00:
1.83 djm 99: case KEY_DSA_CERT:
1.38 markus 100: if ((dsa = DSA_new()) == NULL)
101: fatal("key_new: DSA_new failed");
102: if ((dsa->p = BN_new()) == NULL)
103: fatal("key_new: BN_new failed");
104: if ((dsa->q = BN_new()) == NULL)
105: fatal("key_new: BN_new failed");
106: if ((dsa->g = BN_new()) == NULL)
107: fatal("key_new: BN_new failed");
108: if ((dsa->pub_key = BN_new()) == NULL)
109: fatal("key_new: BN_new failed");
1.1 markus 110: k->dsa = dsa;
111: break;
1.92 djm 112: case KEY_ECDSA:
113: case KEY_ECDSA_CERT:
114: /* Cannot do anything until we know the group */
115: break;
1.12 markus 116: case KEY_UNSPEC:
1.1 markus 117: break;
118: default:
119: fatal("key_new: bad key type %d", k->type);
120: break;
121: }
1.83 djm 122:
123: if (key_is_cert(k))
124: k->cert = cert_new();
125:
1.1 markus 126: return k;
127: }
1.45 deraadt 128:
1.83 djm 129: void
130: key_add_private(Key *k)
1.12 markus 131: {
132: switch (k->type) {
133: case KEY_RSA1:
134: case KEY_RSA:
1.87 djm 135: case KEY_RSA_CERT_V00:
1.83 djm 136: case KEY_RSA_CERT:
1.38 markus 137: if ((k->rsa->d = BN_new()) == NULL)
138: fatal("key_new_private: BN_new failed");
139: if ((k->rsa->iqmp = BN_new()) == NULL)
140: fatal("key_new_private: BN_new failed");
141: if ((k->rsa->q = BN_new()) == NULL)
142: fatal("key_new_private: BN_new failed");
143: if ((k->rsa->p = BN_new()) == NULL)
144: fatal("key_new_private: BN_new failed");
145: if ((k->rsa->dmq1 = BN_new()) == NULL)
146: fatal("key_new_private: BN_new failed");
147: if ((k->rsa->dmp1 = BN_new()) == NULL)
148: fatal("key_new_private: BN_new failed");
1.12 markus 149: break;
150: case KEY_DSA:
1.87 djm 151: case KEY_DSA_CERT_V00:
1.83 djm 152: case KEY_DSA_CERT:
1.38 markus 153: if ((k->dsa->priv_key = BN_new()) == NULL)
154: fatal("key_new_private: BN_new failed");
1.12 markus 155: break;
1.92 djm 156: case KEY_ECDSA:
157: case KEY_ECDSA_CERT:
158: /* Cannot do anything until we know the group */
159: break;
1.12 markus 160: case KEY_UNSPEC:
161: break;
162: default:
163: break;
164: }
1.83 djm 165: }
166:
167: Key *
168: key_new_private(int type)
169: {
170: Key *k = key_new(type);
171:
172: key_add_private(k);
1.12 markus 173: return k;
174: }
1.45 deraadt 175:
1.83 djm 176: static void
177: cert_free(struct KeyCert *cert)
178: {
179: u_int i;
180:
181: buffer_free(&cert->certblob);
1.87 djm 182: buffer_free(&cert->critical);
183: buffer_free(&cert->extensions);
1.103 ! djm 184: free(cert->key_id);
1.83 djm 185: for (i = 0; i < cert->nprincipals; i++)
1.103 ! djm 186: free(cert->principals[i]);
! 187: free(cert->principals);
1.83 djm 188: if (cert->signature_key != NULL)
189: key_free(cert->signature_key);
1.103 ! djm 190: free(cert);
1.83 djm 191: }
192:
1.1 markus 193: void
194: key_free(Key *k)
195: {
1.60 djm 196: if (k == NULL)
1.62 deraadt 197: fatal("key_free: key is NULL");
1.1 markus 198: switch (k->type) {
1.12 markus 199: case KEY_RSA1:
1.1 markus 200: case KEY_RSA:
1.87 djm 201: case KEY_RSA_CERT_V00:
1.83 djm 202: case KEY_RSA_CERT:
1.1 markus 203: if (k->rsa != NULL)
204: RSA_free(k->rsa);
205: k->rsa = NULL;
206: break;
207: case KEY_DSA:
1.87 djm 208: case KEY_DSA_CERT_V00:
1.83 djm 209: case KEY_DSA_CERT:
1.1 markus 210: if (k->dsa != NULL)
211: DSA_free(k->dsa);
212: k->dsa = NULL;
213: break;
1.92 djm 214: case KEY_ECDSA:
215: case KEY_ECDSA_CERT:
216: if (k->ecdsa != NULL)
217: EC_KEY_free(k->ecdsa);
218: k->ecdsa = NULL;
219: break;
1.12 markus 220: case KEY_UNSPEC:
221: break;
1.1 markus 222: default:
223: fatal("key_free: bad key type %d", k->type);
224: break;
225: }
1.83 djm 226: if (key_is_cert(k)) {
227: if (k->cert != NULL)
228: cert_free(k->cert);
229: k->cert = NULL;
230: }
231:
1.103 ! djm 232: free(k);
1.1 markus 233: }
1.55 jakob 234:
1.83 djm 235: static int
236: cert_compare(struct KeyCert *a, struct KeyCert *b)
237: {
238: if (a == NULL && b == NULL)
239: return 1;
240: if (a == NULL || b == NULL)
241: return 0;
242: if (buffer_len(&a->certblob) != buffer_len(&b->certblob))
243: return 0;
1.90 djm 244: if (timingsafe_bcmp(buffer_ptr(&a->certblob), buffer_ptr(&b->certblob),
1.83 djm 245: buffer_len(&a->certblob)) != 0)
246: return 0;
247: return 1;
248: }
249:
250: /*
251: * Compare public portions of key only, allowing comparisons between
252: * certificates and plain keys too.
253: */
1.1 markus 254: int
1.83 djm 255: key_equal_public(const Key *a, const Key *b)
1.1 markus 256: {
1.92 djm 257: BN_CTX *bnctx;
258:
1.83 djm 259: if (a == NULL || b == NULL ||
260: key_type_plain(a->type) != key_type_plain(b->type))
1.1 markus 261: return 0;
1.83 djm 262:
1.1 markus 263: switch (a->type) {
1.12 markus 264: case KEY_RSA1:
1.87 djm 265: case KEY_RSA_CERT_V00:
1.83 djm 266: case KEY_RSA_CERT:
1.1 markus 267: case KEY_RSA:
268: return a->rsa != NULL && b->rsa != NULL &&
269: BN_cmp(a->rsa->e, b->rsa->e) == 0 &&
270: BN_cmp(a->rsa->n, b->rsa->n) == 0;
1.87 djm 271: case KEY_DSA_CERT_V00:
1.83 djm 272: case KEY_DSA_CERT:
1.1 markus 273: case KEY_DSA:
274: return a->dsa != NULL && b->dsa != NULL &&
275: BN_cmp(a->dsa->p, b->dsa->p) == 0 &&
276: BN_cmp(a->dsa->q, b->dsa->q) == 0 &&
277: BN_cmp(a->dsa->g, b->dsa->g) == 0 &&
278: BN_cmp(a->dsa->pub_key, b->dsa->pub_key) == 0;
1.92 djm 279: case KEY_ECDSA_CERT:
280: case KEY_ECDSA:
281: if (a->ecdsa == NULL || b->ecdsa == NULL ||
282: EC_KEY_get0_public_key(a->ecdsa) == NULL ||
283: EC_KEY_get0_public_key(b->ecdsa) == NULL)
284: return 0;
285: if ((bnctx = BN_CTX_new()) == NULL)
286: fatal("%s: BN_CTX_new failed", __func__);
287: if (EC_GROUP_cmp(EC_KEY_get0_group(a->ecdsa),
288: EC_KEY_get0_group(b->ecdsa), bnctx) != 0 ||
289: EC_POINT_cmp(EC_KEY_get0_group(a->ecdsa),
290: EC_KEY_get0_public_key(a->ecdsa),
291: EC_KEY_get0_public_key(b->ecdsa), bnctx) != 0) {
292: BN_CTX_free(bnctx);
293: return 0;
294: }
295: BN_CTX_free(bnctx);
296: return 1;
1.1 markus 297: default:
1.3 markus 298: fatal("key_equal: bad key type %d", a->type);
1.1 markus 299: }
1.78 stevesk 300: /* NOTREACHED */
1.1 markus 301: }
302:
1.83 djm 303: int
304: key_equal(const Key *a, const Key *b)
305: {
306: if (a == NULL || b == NULL || a->type != b->type)
307: return 0;
308: if (key_is_cert(a)) {
309: if (!cert_compare(a->cert, b->cert))
310: return 0;
311: }
312: return key_equal_public(a, b);
313: }
314:
1.52 jakob 315: u_char*
1.100 djm 316: key_fingerprint_raw(const Key *k, enum fp_type dgst_type,
317: u_int *dgst_raw_length)
1.1 markus 318: {
1.41 markus 319: const EVP_MD *md = NULL;
1.21 markus 320: EVP_MD_CTX ctx;
1.13 markus 321: u_char *blob = NULL;
1.19 jakob 322: u_char *retval = NULL;
1.40 markus 323: u_int len = 0;
1.100 djm 324: int nlen, elen;
1.1 markus 325:
1.19 jakob 326: *dgst_raw_length = 0;
327:
1.21 markus 328: switch (dgst_type) {
329: case SSH_FP_MD5:
330: md = EVP_md5();
331: break;
332: case SSH_FP_SHA1:
333: md = EVP_sha1();
1.99 djm 334: break;
335: case SSH_FP_SHA256:
336: md = EVP_sha256();
1.21 markus 337: break;
338: default:
339: fatal("key_fingerprint_raw: bad digest type %d",
340: dgst_type);
341: }
1.1 markus 342: switch (k->type) {
1.12 markus 343: case KEY_RSA1:
1.1 markus 344: nlen = BN_num_bytes(k->rsa->n);
345: elen = BN_num_bytes(k->rsa->e);
346: len = nlen + elen;
1.3 markus 347: blob = xmalloc(len);
348: BN_bn2bin(k->rsa->n, blob);
349: BN_bn2bin(k->rsa->e, blob + nlen);
1.1 markus 350: break;
351: case KEY_DSA:
1.92 djm 352: case KEY_ECDSA:
1.12 markus 353: case KEY_RSA:
354: key_to_blob(k, &blob, &len);
355: break;
1.87 djm 356: case KEY_DSA_CERT_V00:
357: case KEY_RSA_CERT_V00:
1.83 djm 358: case KEY_DSA_CERT:
1.92 djm 359: case KEY_ECDSA_CERT:
1.83 djm 360: case KEY_RSA_CERT:
361: /* We want a fingerprint of the _key_ not of the cert */
1.100 djm 362: to_blob(k, &blob, &len, 1);
1.83 djm 363: break;
1.12 markus 364: case KEY_UNSPEC:
365: return retval;
1.1 markus 366: default:
1.19 jakob 367: fatal("key_fingerprint_raw: bad key type %d", k->type);
1.1 markus 368: break;
369: }
1.3 markus 370: if (blob != NULL) {
1.19 jakob 371: retval = xmalloc(EVP_MAX_MD_SIZE);
1.8 markus 372: EVP_DigestInit(&ctx, md);
373: EVP_DigestUpdate(&ctx, blob, len);
1.39 markus 374: EVP_DigestFinal(&ctx, retval, dgst_raw_length);
1.3 markus 375: memset(blob, 0, len);
1.103 ! djm 376: free(blob);
1.19 jakob 377: } else {
378: fatal("key_fingerprint_raw: blob is null");
1.1 markus 379: }
1.19 jakob 380: return retval;
381: }
382:
1.46 deraadt 383: static char *
384: key_fingerprint_hex(u_char *dgst_raw, u_int dgst_raw_len)
1.19 jakob 385: {
386: char *retval;
1.58 djm 387: u_int i;
1.19 jakob 388:
1.63 djm 389: retval = xcalloc(1, dgst_raw_len * 3 + 1);
1.36 deraadt 390: for (i = 0; i < dgst_raw_len; i++) {
1.19 jakob 391: char hex[4];
392: snprintf(hex, sizeof(hex), "%02x:", dgst_raw[i]);
1.54 avsm 393: strlcat(retval, hex, dgst_raw_len * 3 + 1);
1.19 jakob 394: }
1.54 avsm 395:
396: /* Remove the trailing ':' character */
1.19 jakob 397: retval[(dgst_raw_len * 3) - 1] = '\0';
398: return retval;
399: }
400:
1.46 deraadt 401: static char *
402: key_fingerprint_bubblebabble(u_char *dgst_raw, u_int dgst_raw_len)
1.19 jakob 403: {
404: char vowels[] = { 'a', 'e', 'i', 'o', 'u', 'y' };
405: char consonants[] = { 'b', 'c', 'd', 'f', 'g', 'h', 'k', 'l', 'm',
406: 'n', 'p', 'r', 's', 't', 'v', 'z', 'x' };
1.20 jakob 407: u_int i, j = 0, rounds, seed = 1;
1.19 jakob 408: char *retval;
409:
410: rounds = (dgst_raw_len / 2) + 1;
1.63 djm 411: retval = xcalloc((rounds * 6), sizeof(char));
1.20 jakob 412: retval[j++] = 'x';
413: for (i = 0; i < rounds; i++) {
1.19 jakob 414: u_int idx0, idx1, idx2, idx3, idx4;
1.20 jakob 415: if ((i + 1 < rounds) || (dgst_raw_len % 2 != 0)) {
416: idx0 = (((((u_int)(dgst_raw[2 * i])) >> 6) & 3) +
1.19 jakob 417: seed) % 6;
1.20 jakob 418: idx1 = (((u_int)(dgst_raw[2 * i])) >> 2) & 15;
419: idx2 = ((((u_int)(dgst_raw[2 * i])) & 3) +
1.19 jakob 420: (seed / 6)) % 6;
1.20 jakob 421: retval[j++] = vowels[idx0];
422: retval[j++] = consonants[idx1];
423: retval[j++] = vowels[idx2];
424: if ((i + 1) < rounds) {
425: idx3 = (((u_int)(dgst_raw[(2 * i) + 1])) >> 4) & 15;
426: idx4 = (((u_int)(dgst_raw[(2 * i) + 1]))) & 15;
427: retval[j++] = consonants[idx3];
428: retval[j++] = '-';
429: retval[j++] = consonants[idx4];
1.19 jakob 430: seed = ((seed * 5) +
1.20 jakob 431: ((((u_int)(dgst_raw[2 * i])) * 7) +
432: ((u_int)(dgst_raw[(2 * i) + 1])))) % 36;
1.19 jakob 433: }
434: } else {
435: idx0 = seed % 6;
436: idx1 = 16;
437: idx2 = seed / 6;
1.20 jakob 438: retval[j++] = vowels[idx0];
439: retval[j++] = consonants[idx1];
440: retval[j++] = vowels[idx2];
1.19 jakob 441: }
442: }
1.20 jakob 443: retval[j++] = 'x';
444: retval[j++] = '\0';
1.19 jakob 445: return retval;
446: }
447:
1.70 grunk 448: /*
449: * Draw an ASCII-Art representing the fingerprint so human brain can
450: * profit from its built-in pattern recognition ability.
451: * This technique is called "random art" and can be found in some
452: * scientific publications like this original paper:
453: *
454: * "Hash Visualization: a New Technique to improve Real-World Security",
455: * Perrig A. and Song D., 1999, International Workshop on Cryptographic
456: * Techniques and E-Commerce (CrypTEC '99)
457: * sparrow.ece.cmu.edu/~adrian/projects/validation/validation.pdf
458: *
459: * The subject came up in a talk by Dan Kaminsky, too.
460: *
461: * If you see the picture is different, the key is different.
462: * If the picture looks the same, you still know nothing.
463: *
464: * The algorithm used here is a worm crawling over a discrete plane,
465: * leaving a trace (augmenting the field) everywhere it goes.
466: * Movement is taken from dgst_raw 2bit-wise. Bumping into walls
467: * makes the respective movement vector be ignored for this turn.
468: * Graphs are not unambiguous, because circles in graphs can be
469: * walked in either direction.
470: */
1.74 grunk 471:
472: /*
473: * Field sizes for the random art. Have to be odd, so the starting point
474: * can be in the exact middle of the picture, and FLDBASE should be >=8 .
475: * Else pictures would be too dense, and drawing the frame would
476: * fail, too, because the key type would not fit in anymore.
477: */
478: #define FLDBASE 8
479: #define FLDSIZE_Y (FLDBASE + 1)
480: #define FLDSIZE_X (FLDBASE * 2 + 1)
1.70 grunk 481: static char *
1.74 grunk 482: key_fingerprint_randomart(u_char *dgst_raw, u_int dgst_raw_len, const Key *k)
1.70 grunk 483: {
484: /*
485: * Chars to be used after each other every time the worm
486: * intersects with itself. Matter of taste.
487: */
1.75 grunk 488: char *augmentation_string = " .o+=*BOX@%&#/^SE";
1.70 grunk 489: char *retval, *p;
1.71 otto 490: u_char field[FLDSIZE_X][FLDSIZE_Y];
1.70 grunk 491: u_int i, b;
492: int x, y;
1.72 grunk 493: size_t len = strlen(augmentation_string) - 1;
1.70 grunk 494:
495: retval = xcalloc(1, (FLDSIZE_X + 3) * (FLDSIZE_Y + 2));
496:
497: /* initialize field */
1.71 otto 498: memset(field, 0, FLDSIZE_X * FLDSIZE_Y * sizeof(char));
1.70 grunk 499: x = FLDSIZE_X / 2;
500: y = FLDSIZE_Y / 2;
501:
502: /* process raw key */
503: for (i = 0; i < dgst_raw_len; i++) {
504: int input;
505: /* each byte conveys four 2-bit move commands */
506: input = dgst_raw[i];
507: for (b = 0; b < 4; b++) {
508: /* evaluate 2 bit, rest is shifted later */
509: x += (input & 0x1) ? 1 : -1;
510: y += (input & 0x2) ? 1 : -1;
511:
512: /* assure we are still in bounds */
513: x = MAX(x, 0);
514: y = MAX(y, 0);
515: x = MIN(x, FLDSIZE_X - 1);
516: y = MIN(y, FLDSIZE_Y - 1);
517:
518: /* augment the field */
1.79 grunk 519: if (field[x][y] < len - 2)
520: field[x][y]++;
1.70 grunk 521: input = input >> 2;
522: }
523: }
1.75 grunk 524:
525: /* mark starting point and end point*/
526: field[FLDSIZE_X / 2][FLDSIZE_Y / 2] = len - 1;
527: field[x][y] = len;
1.70 grunk 528:
529: /* fill in retval */
1.77 otto 530: snprintf(retval, FLDSIZE_X, "+--[%4s %4u]", key_type(k), key_size(k));
1.74 grunk 531: p = strchr(retval, '\0');
1.70 grunk 532:
533: /* output upper border */
1.77 otto 534: for (i = p - retval - 1; i < FLDSIZE_X; i++)
1.70 grunk 535: *p++ = '-';
536: *p++ = '+';
537: *p++ = '\n';
538:
539: /* output content */
540: for (y = 0; y < FLDSIZE_Y; y++) {
541: *p++ = '|';
542: for (x = 0; x < FLDSIZE_X; x++)
1.72 grunk 543: *p++ = augmentation_string[MIN(field[x][y], len)];
1.70 grunk 544: *p++ = '|';
545: *p++ = '\n';
546: }
547:
548: /* output lower border */
549: *p++ = '+';
550: for (i = 0; i < FLDSIZE_X; i++)
551: *p++ = '-';
552: *p++ = '+';
553:
554: return retval;
555: }
556:
1.46 deraadt 557: char *
1.83 djm 558: key_fingerprint(Key *k, enum fp_type dgst_type, enum fp_rep dgst_rep)
1.19 jakob 559: {
1.23 markus 560: char *retval = NULL;
1.19 jakob 561: u_char *dgst_raw;
1.39 markus 562: u_int dgst_raw_len;
1.36 deraadt 563:
1.19 jakob 564: dgst_raw = key_fingerprint_raw(k, dgst_type, &dgst_raw_len);
565: if (!dgst_raw)
1.22 markus 566: fatal("key_fingerprint: null from key_fingerprint_raw()");
1.35 deraadt 567: switch (dgst_rep) {
1.19 jakob 568: case SSH_FP_HEX:
569: retval = key_fingerprint_hex(dgst_raw, dgst_raw_len);
570: break;
571: case SSH_FP_BUBBLEBABBLE:
572: retval = key_fingerprint_bubblebabble(dgst_raw, dgst_raw_len);
1.70 grunk 573: break;
574: case SSH_FP_RANDOMART:
1.74 grunk 575: retval = key_fingerprint_randomart(dgst_raw, dgst_raw_len, k);
1.19 jakob 576: break;
577: default:
1.80 stevesk 578: fatal("key_fingerprint: bad digest representation %d",
1.19 jakob 579: dgst_rep);
580: break;
581: }
582: memset(dgst_raw, 0, dgst_raw_len);
1.103 ! djm 583: free(dgst_raw);
1.1 markus 584: return retval;
585: }
586:
587: /*
588: * Reads a multiple-precision integer in decimal from the buffer, and advances
589: * the pointer. The integer must already be initialized. This function is
590: * permitted to modify the buffer. This leaves *cpp to point just beyond the
591: * last processed (and maybe modified) character. Note that this may modify
592: * the buffer containing the number.
593: */
1.27 itojun 594: static int
1.1 markus 595: read_bignum(char **cpp, BIGNUM * value)
596: {
597: char *cp = *cpp;
598: int old;
599:
600: /* Skip any leading whitespace. */
601: for (; *cp == ' ' || *cp == '\t'; cp++)
602: ;
603:
604: /* Check that it begins with a decimal digit. */
605: if (*cp < '0' || *cp > '9')
606: return 0;
607:
608: /* Save starting position. */
609: *cpp = cp;
610:
611: /* Move forward until all decimal digits skipped. */
612: for (; *cp >= '0' && *cp <= '9'; cp++)
613: ;
614:
615: /* Save the old terminating character, and replace it by \0. */
616: old = *cp;
617: *cp = 0;
618:
619: /* Parse the number. */
620: if (BN_dec2bn(&value, *cpp) == 0)
621: return 0;
622:
623: /* Restore old terminating character. */
624: *cp = old;
625:
626: /* Move beyond the number and return success. */
627: *cpp = cp;
628: return 1;
629: }
1.45 deraadt 630:
1.27 itojun 631: static int
1.1 markus 632: write_bignum(FILE *f, BIGNUM *num)
633: {
634: char *buf = BN_bn2dec(num);
635: if (buf == NULL) {
636: error("write_bignum: BN_bn2dec() failed");
637: return 0;
638: }
639: fprintf(f, " %s", buf);
1.33 markus 640: OPENSSL_free(buf);
1.1 markus 641: return 1;
642: }
1.12 markus 643:
1.32 markus 644: /* returns 1 ok, -1 error */
1.12 markus 645: int
1.3 markus 646: key_read(Key *ret, char **cpp)
1.1 markus 647: {
1.3 markus 648: Key *k;
1.12 markus 649: int success = -1;
650: char *cp, *space;
1.92 djm 651: int len, n, type, curve_nid = -1;
1.12 markus 652: u_int bits;
1.13 markus 653: u_char *blob;
1.3 markus 654:
655: cp = *cpp;
656:
1.35 deraadt 657: switch (ret->type) {
1.12 markus 658: case KEY_RSA1:
1.3 markus 659: /* Get number of bits. */
660: if (*cp < '0' || *cp > '9')
1.12 markus 661: return -1; /* Bad bit count... */
1.3 markus 662: for (bits = 0; *cp >= '0' && *cp <= '9'; cp++)
663: bits = 10 * bits + *cp - '0';
1.1 markus 664: if (bits == 0)
1.12 markus 665: return -1;
1.3 markus 666: *cpp = cp;
1.1 markus 667: /* Get public exponent, public modulus. */
668: if (!read_bignum(cpp, ret->rsa->e))
1.12 markus 669: return -1;
1.1 markus 670: if (!read_bignum(cpp, ret->rsa->n))
1.12 markus 671: return -1;
1.82 dtucker 672: /* validate the claimed number of bits */
673: if ((u_int)BN_num_bits(ret->rsa->n) != bits) {
674: verbose("key_read: claimed key size %d does not match "
675: "actual %d", bits, BN_num_bits(ret->rsa->n));
676: return -1;
677: }
1.12 markus 678: success = 1;
1.1 markus 679: break;
1.12 markus 680: case KEY_UNSPEC:
681: case KEY_RSA:
1.1 markus 682: case KEY_DSA:
1.92 djm 683: case KEY_ECDSA:
1.87 djm 684: case KEY_DSA_CERT_V00:
685: case KEY_RSA_CERT_V00:
1.83 djm 686: case KEY_DSA_CERT:
1.92 djm 687: case KEY_ECDSA_CERT:
1.83 djm 688: case KEY_RSA_CERT:
1.12 markus 689: space = strchr(cp, ' ');
690: if (space == NULL) {
1.50 markus 691: debug3("key_read: missing whitespace");
1.12 markus 692: return -1;
693: }
694: *space = '\0';
695: type = key_type_from_name(cp);
1.92 djm 696: if (key_type_plain(type) == KEY_ECDSA &&
697: (curve_nid = key_ecdsa_nid_from_name(cp)) == -1) {
698: debug("key_read: invalid curve");
699: return -1;
700: }
1.12 markus 701: *space = ' ';
702: if (type == KEY_UNSPEC) {
1.50 markus 703: debug3("key_read: missing keytype");
1.12 markus 704: return -1;
705: }
706: cp = space+1;
707: if (*cp == '\0') {
708: debug3("key_read: short string");
709: return -1;
710: }
711: if (ret->type == KEY_UNSPEC) {
712: ret->type = type;
713: } else if (ret->type != type) {
714: /* is a key, but different type */
715: debug3("key_read: type mismatch");
1.32 markus 716: return -1;
1.12 markus 717: }
1.3 markus 718: len = 2*strlen(cp);
719: blob = xmalloc(len);
720: n = uudecode(cp, blob, len);
1.6 markus 721: if (n < 0) {
1.7 markus 722: error("key_read: uudecode %s failed", cp);
1.103 ! djm 723: free(blob);
1.12 markus 724: return -1;
1.6 markus 725: }
1.53 markus 726: k = key_from_blob(blob, (u_int)n);
1.103 ! djm 727: free(blob);
1.7 markus 728: if (k == NULL) {
1.12 markus 729: error("key_read: key_from_blob %s failed", cp);
730: return -1;
1.7 markus 731: }
1.12 markus 732: if (k->type != type) {
733: error("key_read: type mismatch: encoding error");
734: key_free(k);
735: return -1;
736: }
1.92 djm 737: if (key_type_plain(type) == KEY_ECDSA &&
738: curve_nid != k->ecdsa_nid) {
739: error("key_read: type mismatch: EC curve mismatch");
740: key_free(k);
741: return -1;
742: }
1.12 markus 743: /*XXXX*/
1.83 djm 744: if (key_is_cert(ret)) {
745: if (!key_is_cert(k)) {
746: error("key_read: loaded key is not a cert");
747: key_free(k);
748: return -1;
749: }
750: if (ret->cert != NULL)
751: cert_free(ret->cert);
752: ret->cert = k->cert;
753: k->cert = NULL;
754: }
755: if (key_type_plain(ret->type) == KEY_RSA) {
1.12 markus 756: if (ret->rsa != NULL)
757: RSA_free(ret->rsa);
758: ret->rsa = k->rsa;
759: k->rsa = NULL;
760: #ifdef DEBUG_PK
761: RSA_print_fp(stderr, ret->rsa, 8);
762: #endif
1.83 djm 763: }
764: if (key_type_plain(ret->type) == KEY_DSA) {
1.12 markus 765: if (ret->dsa != NULL)
766: DSA_free(ret->dsa);
767: ret->dsa = k->dsa;
768: k->dsa = NULL;
769: #ifdef DEBUG_PK
770: DSA_print_fp(stderr, ret->dsa, 8);
771: #endif
772: }
1.92 djm 773: if (key_type_plain(ret->type) == KEY_ECDSA) {
774: if (ret->ecdsa != NULL)
775: EC_KEY_free(ret->ecdsa);
776: ret->ecdsa = k->ecdsa;
777: ret->ecdsa_nid = k->ecdsa_nid;
778: k->ecdsa = NULL;
779: k->ecdsa_nid = -1;
780: #ifdef DEBUG_PK
781: key_dump_ec_key(ret->ecdsa);
782: #endif
783: }
1.83 djm 784: success = 1;
1.12 markus 785: /*XXXX*/
1.34 markus 786: key_free(k);
1.12 markus 787: if (success != 1)
788: break;
1.7 markus 789: /* advance cp: skip whitespace and data */
790: while (*cp == ' ' || *cp == '\t')
791: cp++;
792: while (*cp != '\0' && *cp != ' ' && *cp != '\t')
793: cp++;
794: *cpp = cp;
1.1 markus 795: break;
796: default:
1.3 markus 797: fatal("key_read: bad key type: %d", ret->type);
1.1 markus 798: break;
799: }
1.12 markus 800: return success;
1.1 markus 801: }
1.45 deraadt 802:
1.1 markus 803: int
1.55 jakob 804: key_write(const Key *key, FILE *f)
1.1 markus 805: {
1.40 markus 806: int n, success = 0;
807: u_int len, bits = 0;
1.49 markus 808: u_char *blob;
809: char *uu;
1.1 markus 810:
1.83 djm 811: if (key_is_cert(key)) {
812: if (key->cert == NULL) {
813: error("%s: no cert data", __func__);
814: return 0;
815: }
816: if (buffer_len(&key->cert->certblob) == 0) {
817: error("%s: no signed certificate blob", __func__);
818: return 0;
819: }
820: }
821:
822: switch (key->type) {
823: case KEY_RSA1:
824: if (key->rsa == NULL)
825: return 0;
1.1 markus 826: /* size of modulus 'n' */
827: bits = BN_num_bits(key->rsa->n);
828: fprintf(f, "%u", bits);
829: if (write_bignum(f, key->rsa->e) &&
1.83 djm 830: write_bignum(f, key->rsa->n))
831: return 1;
832: error("key_write: failed for RSA key");
833: return 0;
834: case KEY_DSA:
1.87 djm 835: case KEY_DSA_CERT_V00:
1.83 djm 836: case KEY_DSA_CERT:
837: if (key->dsa == NULL)
838: return 0;
839: break;
1.92 djm 840: case KEY_ECDSA:
841: case KEY_ECDSA_CERT:
842: if (key->ecdsa == NULL)
843: return 0;
844: break;
1.83 djm 845: case KEY_RSA:
1.87 djm 846: case KEY_RSA_CERT_V00:
1.83 djm 847: case KEY_RSA_CERT:
848: if (key->rsa == NULL)
849: return 0;
850: break;
851: default:
852: return 0;
853: }
854:
855: key_to_blob(key, &blob, &len);
856: uu = xmalloc(2*len);
857: n = uuencode(blob, len, uu, 2*len);
858: if (n > 0) {
859: fprintf(f, "%s %s", key_ssh_name(key), uu);
860: success = 1;
1.1 markus 861: }
1.103 ! djm 862: free(blob);
! 863: free(uu);
1.83 djm 864:
1.1 markus 865: return success;
866: }
1.45 deraadt 867:
1.55 jakob 868: const char *
1.86 stevesk 869: key_cert_type(const Key *k)
870: {
871: switch (k->cert->type) {
872: case SSH2_CERT_TYPE_USER:
873: return "user";
874: case SSH2_CERT_TYPE_HOST:
875: return "host";
876: default:
877: return "unknown";
878: }
1.10 markus 879: }
1.45 deraadt 880:
1.101 djm 881: struct keytype {
882: char *name;
883: char *shortname;
884: int type;
885: int nid;
886: int cert;
887: };
888: static const struct keytype keytypes[] = {
889: { NULL, "RSA1", KEY_RSA1, 0, 0 },
890: { "ssh-rsa", "RSA", KEY_RSA, 0, 0 },
891: { "ssh-dss", "DSA", KEY_DSA, 0, 0 },
892: { "ecdsa-sha2-nistp256", "ECDSA", KEY_ECDSA, NID_X9_62_prime256v1, 0 },
893: { "ecdsa-sha2-nistp384", "ECDSA", KEY_ECDSA, NID_secp384r1, 0 },
894: { "ecdsa-sha2-nistp521", "ECDSA", KEY_ECDSA, NID_secp521r1, 0 },
895: { "ssh-rsa-cert-v01@openssh.com", "RSA-CERT", KEY_RSA_CERT, 0, 1 },
896: { "ssh-dss-cert-v01@openssh.com", "DSA-CERT", KEY_DSA_CERT, 0, 1 },
897: { "ecdsa-sha2-nistp256-cert-v01@openssh.com", "ECDSA-CERT",
898: KEY_ECDSA_CERT, NID_X9_62_prime256v1, 1 },
899: { "ecdsa-sha2-nistp384-cert-v01@openssh.com", "ECDSA-CERT",
900: KEY_ECDSA_CERT, NID_secp384r1, 1 },
901: { "ecdsa-sha2-nistp521-cert-v01@openssh.com", "ECDSA-CERT",
902: KEY_ECDSA_CERT, NID_secp521r1, 1 },
903: { "ssh-rsa-cert-v00@openssh.com", "RSA-CERT-V00",
904: KEY_RSA_CERT_V00, 0, 1 },
905: { "ssh-dss-cert-v00@openssh.com", "DSA-CERT-V00",
906: KEY_DSA_CERT_V00, 0, 1 },
907: { NULL, NULL, -1, -1, 0 }
908: };
909:
910: const char *
911: key_type(const Key *k)
912: {
913: const struct keytype *kt;
914:
915: for (kt = keytypes; kt->type != -1; kt++) {
916: if (kt->type == k->type)
917: return kt->shortname;
918: }
919: return "unknown";
920: }
921:
1.92 djm 922: static const char *
923: key_ssh_name_from_type_nid(int type, int nid)
1.12 markus 924: {
1.101 djm 925: const struct keytype *kt;
926:
927: for (kt = keytypes; kt->type != -1; kt++) {
928: if (kt->type == type && (kt->nid == 0 || kt->nid == nid))
929: return kt->name;
1.12 markus 930: }
931: return "ssh-unknown";
932: }
1.45 deraadt 933:
1.92 djm 934: const char *
935: key_ssh_name(const Key *k)
936: {
937: return key_ssh_name_from_type_nid(k->type, k->ecdsa_nid);
938: }
939:
940: const char *
941: key_ssh_name_plain(const Key *k)
942: {
943: return key_ssh_name_from_type_nid(key_type_plain(k->type),
944: k->ecdsa_nid);
945: }
946:
1.101 djm 947: int
948: key_type_from_name(char *name)
949: {
950: const struct keytype *kt;
951:
952: for (kt = keytypes; kt->type != -1; kt++) {
953: /* Only allow shortname matches for plain key types */
954: if ((kt->name != NULL && strcmp(name, kt->name) == 0) ||
955: (!kt->cert && strcasecmp(kt->shortname, name) == 0))
956: return kt->type;
957: }
958: debug2("key_type_from_name: unknown key type '%s'", name);
959: return KEY_UNSPEC;
960: }
961:
962: int
963: key_ecdsa_nid_from_name(const char *name)
964: {
965: const struct keytype *kt;
966:
967: for (kt = keytypes; kt->type != -1; kt++) {
968: if (kt->type != KEY_ECDSA && kt->type != KEY_ECDSA_CERT)
969: continue;
970: if (kt->name != NULL && strcmp(name, kt->name) == 0)
971: return kt->nid;
972: }
973: debug2("%s: unknown/non-ECDSA key type '%s'", __func__, name);
974: return -1;
975: }
976:
977: char *
978: key_alg_list(void)
979: {
980: char *ret = NULL;
981: size_t nlen, rlen = 0;
982: const struct keytype *kt;
983:
984: for (kt = keytypes; kt->type != -1; kt++) {
985: if (kt->name == NULL)
986: continue;
987: if (ret != NULL)
988: ret[rlen++] = '\n';
989: nlen = strlen(kt->name);
990: ret = xrealloc(ret, 1, rlen + nlen + 2);
991: memcpy(ret + rlen, kt->name, nlen + 1);
992: rlen += nlen;
993: }
994: return ret;
995: }
996:
1.12 markus 997: u_int
1.55 jakob 998: key_size(const Key *k)
1.35 deraadt 999: {
1.10 markus 1000: switch (k->type) {
1.12 markus 1001: case KEY_RSA1:
1.10 markus 1002: case KEY_RSA:
1.87 djm 1003: case KEY_RSA_CERT_V00:
1.83 djm 1004: case KEY_RSA_CERT:
1.10 markus 1005: return BN_num_bits(k->rsa->n);
1006: case KEY_DSA:
1.87 djm 1007: case KEY_DSA_CERT_V00:
1.83 djm 1008: case KEY_DSA_CERT:
1.10 markus 1009: return BN_num_bits(k->dsa->p);
1.92 djm 1010: case KEY_ECDSA:
1011: case KEY_ECDSA_CERT:
1.93 djm 1012: return key_curve_nid_to_bits(k->ecdsa_nid);
1.10 markus 1013: }
1014: return 0;
1.12 markus 1015: }
1016:
1.27 itojun 1017: static RSA *
1.13 markus 1018: rsa_generate_private_key(u_int bits)
1.12 markus 1019: {
1.95 djm 1020: RSA *private = RSA_new();
1021: BIGNUM *f4 = BN_new();
1.61 deraadt 1022:
1.17 stevesk 1023: if (private == NULL)
1.95 djm 1024: fatal("%s: RSA_new failed", __func__);
1025: if (f4 == NULL)
1026: fatal("%s: BN_new failed", __func__);
1027: if (!BN_set_word(f4, RSA_F4))
1028: fatal("%s: BN_new failed", __func__);
1029: if (!RSA_generate_key_ex(private, bits, f4, NULL))
1030: fatal("%s: key generation failed.", __func__);
1031: BN_free(f4);
1.17 stevesk 1032: return private;
1.12 markus 1033: }
1034:
1.27 itojun 1035: static DSA*
1.13 markus 1036: dsa_generate_private_key(u_int bits)
1.12 markus 1037: {
1.95 djm 1038: DSA *private = DSA_new();
1.61 deraadt 1039:
1.12 markus 1040: if (private == NULL)
1.95 djm 1041: fatal("%s: DSA_new failed", __func__);
1042: if (!DSA_generate_parameters_ex(private, bits, NULL, 0, NULL,
1043: NULL, NULL))
1044: fatal("%s: DSA_generate_parameters failed", __func__);
1.12 markus 1045: if (!DSA_generate_key(private))
1.95 djm 1046: fatal("%s: DSA_generate_key failed.", __func__);
1.12 markus 1047: return private;
1048: }
1049:
1.92 djm 1050: int
1051: key_ecdsa_bits_to_nid(int bits)
1052: {
1053: switch (bits) {
1054: case 256:
1055: return NID_X9_62_prime256v1;
1056: case 384:
1057: return NID_secp384r1;
1058: case 521:
1059: return NID_secp521r1;
1060: default:
1061: return -1;
1062: }
1063: }
1064:
1065: int
1.94 djm 1066: key_ecdsa_key_to_nid(EC_KEY *k)
1.92 djm 1067: {
1068: EC_GROUP *eg;
1069: int nids[] = {
1070: NID_X9_62_prime256v1,
1071: NID_secp384r1,
1072: NID_secp521r1,
1073: -1
1074: };
1.94 djm 1075: int nid;
1.92 djm 1076: u_int i;
1077: BN_CTX *bnctx;
1.94 djm 1078: const EC_GROUP *g = EC_KEY_get0_group(k);
1.92 djm 1079:
1.94 djm 1080: /*
1081: * The group may be stored in a ASN.1 encoded private key in one of two
1082: * ways: as a "named group", which is reconstituted by ASN.1 object ID
1083: * or explicit group parameters encoded into the key blob. Only the
1084: * "named group" case sets the group NID for us, but we can figure
1085: * it out for the other case by comparing against all the groups that
1086: * are supported.
1087: */
1088: if ((nid = EC_GROUP_get_curve_name(g)) > 0)
1089: return nid;
1.92 djm 1090: if ((bnctx = BN_CTX_new()) == NULL)
1091: fatal("%s: BN_CTX_new() failed", __func__);
1092: for (i = 0; nids[i] != -1; i++) {
1093: if ((eg = EC_GROUP_new_by_curve_name(nids[i])) == NULL)
1094: fatal("%s: EC_GROUP_new_by_curve_name failed",
1095: __func__);
1.94 djm 1096: if (EC_GROUP_cmp(g, eg, bnctx) == 0)
1.92 djm 1097: break;
1098: EC_GROUP_free(eg);
1099: }
1100: BN_CTX_free(bnctx);
1101: debug3("%s: nid = %d", __func__, nids[i]);
1.94 djm 1102: if (nids[i] != -1) {
1103: /* Use the group with the NID attached */
1104: EC_GROUP_set_asn1_flag(eg, OPENSSL_EC_NAMED_CURVE);
1105: if (EC_KEY_set_group(k, eg) != 1)
1106: fatal("%s: EC_KEY_set_group", __func__);
1107: }
1.92 djm 1108: return nids[i];
1109: }
1110:
1111: static EC_KEY*
1112: ecdsa_generate_private_key(u_int bits, int *nid)
1113: {
1114: EC_KEY *private;
1115:
1116: if ((*nid = key_ecdsa_bits_to_nid(bits)) == -1)
1117: fatal("%s: invalid key length", __func__);
1118: if ((private = EC_KEY_new_by_curve_name(*nid)) == NULL)
1119: fatal("%s: EC_KEY_new_by_curve_name failed", __func__);
1120: if (EC_KEY_generate_key(private) != 1)
1121: fatal("%s: EC_KEY_generate_key failed", __func__);
1.94 djm 1122: EC_KEY_set_asn1_flag(private, OPENSSL_EC_NAMED_CURVE);
1.92 djm 1123: return private;
1124: }
1125:
1.12 markus 1126: Key *
1.13 markus 1127: key_generate(int type, u_int bits)
1.12 markus 1128: {
1129: Key *k = key_new(KEY_UNSPEC);
1130: switch (type) {
1.17 stevesk 1131: case KEY_DSA:
1.12 markus 1132: k->dsa = dsa_generate_private_key(bits);
1133: break;
1.92 djm 1134: case KEY_ECDSA:
1135: k->ecdsa = ecdsa_generate_private_key(bits, &k->ecdsa_nid);
1136: break;
1.12 markus 1137: case KEY_RSA:
1138: case KEY_RSA1:
1139: k->rsa = rsa_generate_private_key(bits);
1140: break;
1.87 djm 1141: case KEY_RSA_CERT_V00:
1142: case KEY_DSA_CERT_V00:
1.83 djm 1143: case KEY_RSA_CERT:
1144: case KEY_DSA_CERT:
1145: fatal("key_generate: cert keys cannot be generated directly");
1.12 markus 1146: default:
1.17 stevesk 1147: fatal("key_generate: unknown type %d", type);
1.12 markus 1148: }
1.17 stevesk 1149: k->type = type;
1.12 markus 1150: return k;
1151: }
1152:
1.83 djm 1153: void
1154: key_cert_copy(const Key *from_key, struct Key *to_key)
1155: {
1156: u_int i;
1157: const struct KeyCert *from;
1158: struct KeyCert *to;
1159:
1160: if (to_key->cert != NULL) {
1161: cert_free(to_key->cert);
1162: to_key->cert = NULL;
1163: }
1164:
1165: if ((from = from_key->cert) == NULL)
1166: return;
1167:
1168: to = to_key->cert = cert_new();
1169:
1170: buffer_append(&to->certblob, buffer_ptr(&from->certblob),
1171: buffer_len(&from->certblob));
1172:
1.87 djm 1173: buffer_append(&to->critical,
1174: buffer_ptr(&from->critical), buffer_len(&from->critical));
1175: buffer_append(&to->extensions,
1176: buffer_ptr(&from->extensions), buffer_len(&from->extensions));
1.83 djm 1177:
1.87 djm 1178: to->serial = from->serial;
1.83 djm 1179: to->type = from->type;
1180: to->key_id = from->key_id == NULL ? NULL : xstrdup(from->key_id);
1181: to->valid_after = from->valid_after;
1182: to->valid_before = from->valid_before;
1183: to->signature_key = from->signature_key == NULL ?
1184: NULL : key_from_private(from->signature_key);
1185:
1186: to->nprincipals = from->nprincipals;
1187: if (to->nprincipals > CERT_MAX_PRINCIPALS)
1188: fatal("%s: nprincipals (%u) > CERT_MAX_PRINCIPALS (%u)",
1189: __func__, to->nprincipals, CERT_MAX_PRINCIPALS);
1190: if (to->nprincipals > 0) {
1191: to->principals = xcalloc(from->nprincipals,
1192: sizeof(*to->principals));
1193: for (i = 0; i < to->nprincipals; i++)
1194: to->principals[i] = xstrdup(from->principals[i]);
1195: }
1196: }
1197:
1.12 markus 1198: Key *
1.55 jakob 1199: key_from_private(const Key *k)
1.12 markus 1200: {
1201: Key *n = NULL;
1202: switch (k->type) {
1.17 stevesk 1203: case KEY_DSA:
1.87 djm 1204: case KEY_DSA_CERT_V00:
1.83 djm 1205: case KEY_DSA_CERT:
1.12 markus 1206: n = key_new(k->type);
1.68 markus 1207: if ((BN_copy(n->dsa->p, k->dsa->p) == NULL) ||
1208: (BN_copy(n->dsa->q, k->dsa->q) == NULL) ||
1209: (BN_copy(n->dsa->g, k->dsa->g) == NULL) ||
1210: (BN_copy(n->dsa->pub_key, k->dsa->pub_key) == NULL))
1211: fatal("key_from_private: BN_copy failed");
1.12 markus 1212: break;
1.92 djm 1213: case KEY_ECDSA:
1214: case KEY_ECDSA_CERT:
1215: n = key_new(k->type);
1216: n->ecdsa_nid = k->ecdsa_nid;
1217: if ((n->ecdsa = EC_KEY_new_by_curve_name(k->ecdsa_nid)) == NULL)
1218: fatal("%s: EC_KEY_new_by_curve_name failed", __func__);
1219: if (EC_KEY_set_public_key(n->ecdsa,
1220: EC_KEY_get0_public_key(k->ecdsa)) != 1)
1221: fatal("%s: EC_KEY_set_public_key failed", __func__);
1222: break;
1.12 markus 1223: case KEY_RSA:
1224: case KEY_RSA1:
1.87 djm 1225: case KEY_RSA_CERT_V00:
1.83 djm 1226: case KEY_RSA_CERT:
1.12 markus 1227: n = key_new(k->type);
1.68 markus 1228: if ((BN_copy(n->rsa->n, k->rsa->n) == NULL) ||
1229: (BN_copy(n->rsa->e, k->rsa->e) == NULL))
1230: fatal("key_from_private: BN_copy failed");
1.12 markus 1231: break;
1232: default:
1.17 stevesk 1233: fatal("key_from_private: unknown type %d", k->type);
1.12 markus 1234: break;
1235: }
1.83 djm 1236: if (key_is_cert(k))
1237: key_cert_copy(k, n);
1.12 markus 1238: return n;
1.92 djm 1239: }
1240:
1241: int
1.25 markus 1242: key_names_valid2(const char *names)
1243: {
1244: char *s, *cp, *p;
1245:
1246: if (names == NULL || strcmp(names, "") == 0)
1247: return 0;
1248: s = cp = xstrdup(names);
1249: for ((p = strsep(&cp, ",")); p && *p != '\0';
1.36 deraadt 1250: (p = strsep(&cp, ","))) {
1.25 markus 1251: switch (key_type_from_name(p)) {
1252: case KEY_RSA1:
1253: case KEY_UNSPEC:
1.103 ! djm 1254: free(s);
1.25 markus 1255: return 0;
1256: }
1257: }
1258: debug3("key names ok: [%s]", names);
1.103 ! djm 1259: free(s);
1.25 markus 1260: return 1;
1.12 markus 1261: }
1262:
1.83 djm 1263: static int
1264: cert_parse(Buffer *b, Key *key, const u_char *blob, u_int blen)
1265: {
1.87 djm 1266: u_char *principals, *critical, *exts, *sig_key, *sig;
1267: u_int signed_len, plen, clen, sklen, slen, kidlen, elen;
1.83 djm 1268: Buffer tmp;
1269: char *principal;
1270: int ret = -1;
1.87 djm 1271: int v00 = key->type == KEY_DSA_CERT_V00 ||
1272: key->type == KEY_RSA_CERT_V00;
1.83 djm 1273:
1274: buffer_init(&tmp);
1275:
1276: /* Copy the entire key blob for verification and later serialisation */
1277: buffer_append(&key->cert->certblob, blob, blen);
1278:
1.87 djm 1279: elen = 0; /* Not touched for v00 certs */
1280: principals = exts = critical = sig_key = sig = NULL;
1281: if ((!v00 && buffer_get_int64_ret(&key->cert->serial, b) != 0) ||
1282: buffer_get_int_ret(&key->cert->type, b) != 0 ||
1.91 djm 1283: (key->cert->key_id = buffer_get_cstring_ret(b, &kidlen)) == NULL ||
1.83 djm 1284: (principals = buffer_get_string_ret(b, &plen)) == NULL ||
1285: buffer_get_int64_ret(&key->cert->valid_after, b) != 0 ||
1286: buffer_get_int64_ret(&key->cert->valid_before, b) != 0 ||
1.87 djm 1287: (critical = buffer_get_string_ret(b, &clen)) == NULL ||
1288: (!v00 && (exts = buffer_get_string_ret(b, &elen)) == NULL) ||
1289: (v00 && buffer_get_string_ptr_ret(b, NULL) == NULL) || /* nonce */
1290: buffer_get_string_ptr_ret(b, NULL) == NULL || /* reserved */
1.83 djm 1291: (sig_key = buffer_get_string_ret(b, &sklen)) == NULL) {
1292: error("%s: parse error", __func__);
1.84 djm 1293: goto out;
1294: }
1295:
1.83 djm 1296: /* Signature is left in the buffer so we can calculate this length */
1297: signed_len = buffer_len(&key->cert->certblob) - buffer_len(b);
1298:
1299: if ((sig = buffer_get_string_ret(b, &slen)) == NULL) {
1300: error("%s: parse error", __func__);
1301: goto out;
1302: }
1303:
1304: if (key->cert->type != SSH2_CERT_TYPE_USER &&
1305: key->cert->type != SSH2_CERT_TYPE_HOST) {
1306: error("Unknown certificate type %u", key->cert->type);
1307: goto out;
1308: }
1309:
1310: buffer_append(&tmp, principals, plen);
1311: while (buffer_len(&tmp) > 0) {
1312: if (key->cert->nprincipals >= CERT_MAX_PRINCIPALS) {
1.84 djm 1313: error("%s: Too many principals", __func__);
1.83 djm 1314: goto out;
1315: }
1.91 djm 1316: if ((principal = buffer_get_cstring_ret(&tmp, &plen)) == NULL) {
1.84 djm 1317: error("%s: Principals data invalid", __func__);
1318: goto out;
1319: }
1.83 djm 1320: key->cert->principals = xrealloc(key->cert->principals,
1321: key->cert->nprincipals + 1, sizeof(*key->cert->principals));
1322: key->cert->principals[key->cert->nprincipals++] = principal;
1323: }
1324:
1325: buffer_clear(&tmp);
1326:
1.87 djm 1327: buffer_append(&key->cert->critical, critical, clen);
1328: buffer_append(&tmp, critical, clen);
1.83 djm 1329: /* validate structure */
1330: while (buffer_len(&tmp) != 0) {
1.85 djm 1331: if (buffer_get_string_ptr_ret(&tmp, NULL) == NULL ||
1332: buffer_get_string_ptr_ret(&tmp, NULL) == NULL) {
1.87 djm 1333: error("%s: critical option data invalid", __func__);
1334: goto out;
1335: }
1336: }
1337: buffer_clear(&tmp);
1338:
1339: buffer_append(&key->cert->extensions, exts, elen);
1340: buffer_append(&tmp, exts, elen);
1341: /* validate structure */
1342: while (buffer_len(&tmp) != 0) {
1343: if (buffer_get_string_ptr_ret(&tmp, NULL) == NULL ||
1344: buffer_get_string_ptr_ret(&tmp, NULL) == NULL) {
1345: error("%s: extension data invalid", __func__);
1.83 djm 1346: goto out;
1347: }
1348: }
1349: buffer_clear(&tmp);
1350:
1351: if ((key->cert->signature_key = key_from_blob(sig_key,
1352: sklen)) == NULL) {
1.84 djm 1353: error("%s: Signature key invalid", __func__);
1.83 djm 1354: goto out;
1355: }
1356: if (key->cert->signature_key->type != KEY_RSA &&
1.92 djm 1357: key->cert->signature_key->type != KEY_DSA &&
1358: key->cert->signature_key->type != KEY_ECDSA) {
1.84 djm 1359: error("%s: Invalid signature key type %s (%d)", __func__,
1.83 djm 1360: key_type(key->cert->signature_key),
1361: key->cert->signature_key->type);
1362: goto out;
1363: }
1364:
1365: switch (key_verify(key->cert->signature_key, sig, slen,
1366: buffer_ptr(&key->cert->certblob), signed_len)) {
1367: case 1:
1.84 djm 1368: ret = 0;
1.83 djm 1369: break; /* Good signature */
1370: case 0:
1.84 djm 1371: error("%s: Invalid signature on certificate", __func__);
1.83 djm 1372: goto out;
1373: case -1:
1.84 djm 1374: error("%s: Certificate signature verification failed",
1375: __func__);
1.83 djm 1376: goto out;
1377: }
1378:
1379: out:
1380: buffer_free(&tmp);
1.103 ! djm 1381: free(principals);
! 1382: free(critical);
! 1383: free(exts);
! 1384: free(sig_key);
! 1385: free(sig);
1.83 djm 1386: return ret;
1387: }
1388:
1.12 markus 1389: Key *
1.55 jakob 1390: key_from_blob(const u_char *blob, u_int blen)
1.12 markus 1391: {
1392: Buffer b;
1.92 djm 1393: int rlen, type, nid = -1;
1394: char *ktype = NULL, *curve = NULL;
1.12 markus 1395: Key *key = NULL;
1.92 djm 1396: EC_POINT *q = NULL;
1.12 markus 1397:
1398: #ifdef DEBUG_PK
1399: dump_base64(stderr, blob, blen);
1400: #endif
1401: buffer_init(&b);
1402: buffer_append(&b, blob, blen);
1.91 djm 1403: if ((ktype = buffer_get_cstring_ret(&b, NULL)) == NULL) {
1.57 djm 1404: error("key_from_blob: can't read key type");
1405: goto out;
1406: }
1407:
1.12 markus 1408: type = key_type_from_name(ktype);
1.92 djm 1409: if (key_type_plain(type) == KEY_ECDSA)
1410: nid = key_ecdsa_nid_from_name(ktype);
1.12 markus 1411:
1.35 deraadt 1412: switch (type) {
1.87 djm 1413: case KEY_RSA_CERT:
1414: (void)buffer_get_string_ptr_ret(&b, NULL); /* Skip nonce */
1415: /* FALLTHROUGH */
1.12 markus 1416: case KEY_RSA:
1.87 djm 1417: case KEY_RSA_CERT_V00:
1.12 markus 1418: key = key_new(type);
1.57 djm 1419: if (buffer_get_bignum2_ret(&b, key->rsa->e) == -1 ||
1420: buffer_get_bignum2_ret(&b, key->rsa->n) == -1) {
1421: error("key_from_blob: can't read rsa key");
1.83 djm 1422: badkey:
1.57 djm 1423: key_free(key);
1424: key = NULL;
1425: goto out;
1426: }
1.12 markus 1427: #ifdef DEBUG_PK
1428: RSA_print_fp(stderr, key->rsa, 8);
1429: #endif
1430: break;
1.87 djm 1431: case KEY_DSA_CERT:
1432: (void)buffer_get_string_ptr_ret(&b, NULL); /* Skip nonce */
1433: /* FALLTHROUGH */
1.12 markus 1434: case KEY_DSA:
1.87 djm 1435: case KEY_DSA_CERT_V00:
1.12 markus 1436: key = key_new(type);
1.57 djm 1437: if (buffer_get_bignum2_ret(&b, key->dsa->p) == -1 ||
1438: buffer_get_bignum2_ret(&b, key->dsa->q) == -1 ||
1439: buffer_get_bignum2_ret(&b, key->dsa->g) == -1 ||
1440: buffer_get_bignum2_ret(&b, key->dsa->pub_key) == -1) {
1441: error("key_from_blob: can't read dsa key");
1.83 djm 1442: goto badkey;
1.57 djm 1443: }
1.12 markus 1444: #ifdef DEBUG_PK
1445: DSA_print_fp(stderr, key->dsa, 8);
1446: #endif
1447: break;
1.92 djm 1448: case KEY_ECDSA_CERT:
1449: (void)buffer_get_string_ptr_ret(&b, NULL); /* Skip nonce */
1450: /* FALLTHROUGH */
1451: case KEY_ECDSA:
1452: key = key_new(type);
1453: key->ecdsa_nid = nid;
1454: if ((curve = buffer_get_string_ret(&b, NULL)) == NULL) {
1455: error("key_from_blob: can't read ecdsa curve");
1456: goto badkey;
1457: }
1458: if (key->ecdsa_nid != key_curve_name_to_nid(curve)) {
1459: error("key_from_blob: ecdsa curve doesn't match type");
1460: goto badkey;
1461: }
1462: if (key->ecdsa != NULL)
1463: EC_KEY_free(key->ecdsa);
1464: if ((key->ecdsa = EC_KEY_new_by_curve_name(key->ecdsa_nid))
1465: == NULL)
1466: fatal("key_from_blob: EC_KEY_new_by_curve_name failed");
1467: if ((q = EC_POINT_new(EC_KEY_get0_group(key->ecdsa))) == NULL)
1468: fatal("key_from_blob: EC_POINT_new failed");
1469: if (buffer_get_ecpoint_ret(&b, EC_KEY_get0_group(key->ecdsa),
1470: q) == -1) {
1471: error("key_from_blob: can't read ecdsa key point");
1472: goto badkey;
1473: }
1474: if (key_ec_validate_public(EC_KEY_get0_group(key->ecdsa),
1475: q) != 0)
1476: goto badkey;
1477: if (EC_KEY_set_public_key(key->ecdsa, q) != 1)
1478: fatal("key_from_blob: EC_KEY_set_public_key failed");
1479: #ifdef DEBUG_PK
1480: key_dump_ec_point(EC_KEY_get0_group(key->ecdsa), q);
1481: #endif
1482: break;
1.12 markus 1483: case KEY_UNSPEC:
1484: key = key_new(type);
1485: break;
1486: default:
1487: error("key_from_blob: cannot handle type %s", ktype);
1.57 djm 1488: goto out;
1.12 markus 1489: }
1.83 djm 1490: if (key_is_cert(key) && cert_parse(&b, key, blob, blen) == -1) {
1491: error("key_from_blob: can't parse cert data");
1492: goto badkey;
1493: }
1.12 markus 1494: rlen = buffer_len(&b);
1495: if (key != NULL && rlen != 0)
1496: error("key_from_blob: remaining bytes in key blob %d", rlen);
1.57 djm 1497: out:
1.103 ! djm 1498: free(ktype);
! 1499: free(curve);
1.92 djm 1500: if (q != NULL)
1501: EC_POINT_free(q);
1.12 markus 1502: buffer_free(&b);
1503: return key;
1504: }
1505:
1.100 djm 1506: static int
1507: to_blob(const Key *key, u_char **blobp, u_int *lenp, int force_plain)
1.12 markus 1508: {
1509: Buffer b;
1.100 djm 1510: int len, type;
1.12 markus 1511:
1512: if (key == NULL) {
1513: error("key_to_blob: key == NULL");
1514: return 0;
1515: }
1516: buffer_init(&b);
1.100 djm 1517: type = force_plain ? key_type_plain(key->type) : key->type;
1518: switch (type) {
1.87 djm 1519: case KEY_DSA_CERT_V00:
1520: case KEY_RSA_CERT_V00:
1.83 djm 1521: case KEY_DSA_CERT:
1.92 djm 1522: case KEY_ECDSA_CERT:
1.83 djm 1523: case KEY_RSA_CERT:
1524: /* Use the existing blob */
1525: buffer_append(&b, buffer_ptr(&key->cert->certblob),
1526: buffer_len(&key->cert->certblob));
1527: break;
1.12 markus 1528: case KEY_DSA:
1.100 djm 1529: buffer_put_cstring(&b,
1530: key_ssh_name_from_type_nid(type, key->ecdsa_nid));
1.12 markus 1531: buffer_put_bignum2(&b, key->dsa->p);
1532: buffer_put_bignum2(&b, key->dsa->q);
1533: buffer_put_bignum2(&b, key->dsa->g);
1534: buffer_put_bignum2(&b, key->dsa->pub_key);
1535: break;
1.92 djm 1536: case KEY_ECDSA:
1.100 djm 1537: buffer_put_cstring(&b,
1538: key_ssh_name_from_type_nid(type, key->ecdsa_nid));
1.92 djm 1539: buffer_put_cstring(&b, key_curve_nid_to_name(key->ecdsa_nid));
1540: buffer_put_ecpoint(&b, EC_KEY_get0_group(key->ecdsa),
1541: EC_KEY_get0_public_key(key->ecdsa));
1542: break;
1.12 markus 1543: case KEY_RSA:
1.100 djm 1544: buffer_put_cstring(&b,
1545: key_ssh_name_from_type_nid(type, key->ecdsa_nid));
1.14 markus 1546: buffer_put_bignum2(&b, key->rsa->e);
1.12 markus 1547: buffer_put_bignum2(&b, key->rsa->n);
1548: break;
1549: default:
1.31 markus 1550: error("key_to_blob: unsupported key type %d", key->type);
1551: buffer_free(&b);
1552: return 0;
1.12 markus 1553: }
1554: len = buffer_len(&b);
1.48 markus 1555: if (lenp != NULL)
1556: *lenp = len;
1557: if (blobp != NULL) {
1558: *blobp = xmalloc(len);
1559: memcpy(*blobp, buffer_ptr(&b), len);
1560: }
1.12 markus 1561: memset(buffer_ptr(&b), 0, len);
1562: buffer_free(&b);
1563: return len;
1564: }
1565:
1566: int
1.100 djm 1567: key_to_blob(const Key *key, u_char **blobp, u_int *lenp)
1568: {
1569: return to_blob(key, blobp, lenp, 0);
1570: }
1571:
1572: int
1.12 markus 1573: key_sign(
1.55 jakob 1574: const Key *key,
1.40 markus 1575: u_char **sigp, u_int *lenp,
1.55 jakob 1576: const u_char *data, u_int datalen)
1.12 markus 1577: {
1.35 deraadt 1578: switch (key->type) {
1.87 djm 1579: case KEY_DSA_CERT_V00:
1.83 djm 1580: case KEY_DSA_CERT:
1.12 markus 1581: case KEY_DSA:
1582: return ssh_dss_sign(key, sigp, lenp, data, datalen);
1.92 djm 1583: case KEY_ECDSA_CERT:
1584: case KEY_ECDSA:
1585: return ssh_ecdsa_sign(key, sigp, lenp, data, datalen);
1.87 djm 1586: case KEY_RSA_CERT_V00:
1.83 djm 1587: case KEY_RSA_CERT:
1.12 markus 1588: case KEY_RSA:
1589: return ssh_rsa_sign(key, sigp, lenp, data, datalen);
1590: default:
1.56 markus 1591: error("key_sign: invalid key type %d", key->type);
1.12 markus 1592: return -1;
1593: }
1594: }
1595:
1.44 markus 1596: /*
1597: * key_verify returns 1 for a correct signature, 0 for an incorrect signature
1598: * and -1 on error.
1599: */
1.12 markus 1600: int
1601: key_verify(
1.55 jakob 1602: const Key *key,
1603: const u_char *signature, u_int signaturelen,
1604: const u_char *data, u_int datalen)
1.12 markus 1605: {
1.26 markus 1606: if (signaturelen == 0)
1607: return -1;
1608:
1.35 deraadt 1609: switch (key->type) {
1.87 djm 1610: case KEY_DSA_CERT_V00:
1.83 djm 1611: case KEY_DSA_CERT:
1.12 markus 1612: case KEY_DSA:
1613: return ssh_dss_verify(key, signature, signaturelen, data, datalen);
1.92 djm 1614: case KEY_ECDSA_CERT:
1615: case KEY_ECDSA:
1616: return ssh_ecdsa_verify(key, signature, signaturelen, data, datalen);
1.87 djm 1617: case KEY_RSA_CERT_V00:
1.83 djm 1618: case KEY_RSA_CERT:
1.12 markus 1619: case KEY_RSA:
1620: return ssh_rsa_verify(key, signature, signaturelen, data, datalen);
1621: default:
1.56 markus 1622: error("key_verify: invalid key type %d", key->type);
1.12 markus 1623: return -1;
1624: }
1.42 markus 1625: }
1626:
1627: /* Converts a private to a public key */
1628: Key *
1.55 jakob 1629: key_demote(const Key *k)
1.42 markus 1630: {
1631: Key *pk;
1.43 markus 1632:
1.63 djm 1633: pk = xcalloc(1, sizeof(*pk));
1.42 markus 1634: pk->type = k->type;
1635: pk->flags = k->flags;
1.92 djm 1636: pk->ecdsa_nid = k->ecdsa_nid;
1.42 markus 1637: pk->dsa = NULL;
1.92 djm 1638: pk->ecdsa = NULL;
1.42 markus 1639: pk->rsa = NULL;
1640:
1641: switch (k->type) {
1.87 djm 1642: case KEY_RSA_CERT_V00:
1.83 djm 1643: case KEY_RSA_CERT:
1644: key_cert_copy(k, pk);
1645: /* FALLTHROUGH */
1.42 markus 1646: case KEY_RSA1:
1647: case KEY_RSA:
1648: if ((pk->rsa = RSA_new()) == NULL)
1649: fatal("key_demote: RSA_new failed");
1650: if ((pk->rsa->e = BN_dup(k->rsa->e)) == NULL)
1651: fatal("key_demote: BN_dup failed");
1652: if ((pk->rsa->n = BN_dup(k->rsa->n)) == NULL)
1653: fatal("key_demote: BN_dup failed");
1654: break;
1.87 djm 1655: case KEY_DSA_CERT_V00:
1.83 djm 1656: case KEY_DSA_CERT:
1657: key_cert_copy(k, pk);
1658: /* FALLTHROUGH */
1.42 markus 1659: case KEY_DSA:
1660: if ((pk->dsa = DSA_new()) == NULL)
1661: fatal("key_demote: DSA_new failed");
1662: if ((pk->dsa->p = BN_dup(k->dsa->p)) == NULL)
1663: fatal("key_demote: BN_dup failed");
1664: if ((pk->dsa->q = BN_dup(k->dsa->q)) == NULL)
1665: fatal("key_demote: BN_dup failed");
1666: if ((pk->dsa->g = BN_dup(k->dsa->g)) == NULL)
1667: fatal("key_demote: BN_dup failed");
1668: if ((pk->dsa->pub_key = BN_dup(k->dsa->pub_key)) == NULL)
1669: fatal("key_demote: BN_dup failed");
1670: break;
1.92 djm 1671: case KEY_ECDSA_CERT:
1672: key_cert_copy(k, pk);
1673: /* FALLTHROUGH */
1674: case KEY_ECDSA:
1675: if ((pk->ecdsa = EC_KEY_new_by_curve_name(pk->ecdsa_nid)) == NULL)
1676: fatal("key_demote: EC_KEY_new_by_curve_name failed");
1677: if (EC_KEY_set_public_key(pk->ecdsa,
1678: EC_KEY_get0_public_key(k->ecdsa)) != 1)
1679: fatal("key_demote: EC_KEY_set_public_key failed");
1680: break;
1.42 markus 1681: default:
1682: fatal("key_free: bad key type %d", k->type);
1683: break;
1684: }
1685:
1686: return (pk);
1.83 djm 1687: }
1688:
1689: int
1690: key_is_cert(const Key *k)
1691: {
1.87 djm 1692: if (k == NULL)
1693: return 0;
1694: switch (k->type) {
1695: case KEY_RSA_CERT_V00:
1696: case KEY_DSA_CERT_V00:
1697: case KEY_RSA_CERT:
1698: case KEY_DSA_CERT:
1.92 djm 1699: case KEY_ECDSA_CERT:
1.87 djm 1700: return 1;
1701: default:
1702: return 0;
1703: }
1.83 djm 1704: }
1705:
1706: /* Return the cert-less equivalent to a certified key type */
1707: int
1708: key_type_plain(int type)
1709: {
1710: switch (type) {
1.87 djm 1711: case KEY_RSA_CERT_V00:
1.83 djm 1712: case KEY_RSA_CERT:
1713: return KEY_RSA;
1.87 djm 1714: case KEY_DSA_CERT_V00:
1.83 djm 1715: case KEY_DSA_CERT:
1716: return KEY_DSA;
1.92 djm 1717: case KEY_ECDSA_CERT:
1718: return KEY_ECDSA;
1.83 djm 1719: default:
1720: return type;
1721: }
1722: }
1723:
1724: /* Convert a KEY_RSA or KEY_DSA to their _CERT equivalent */
1725: int
1.87 djm 1726: key_to_certified(Key *k, int legacy)
1.83 djm 1727: {
1728: switch (k->type) {
1729: case KEY_RSA:
1730: k->cert = cert_new();
1.87 djm 1731: k->type = legacy ? KEY_RSA_CERT_V00 : KEY_RSA_CERT;
1.83 djm 1732: return 0;
1733: case KEY_DSA:
1734: k->cert = cert_new();
1.87 djm 1735: k->type = legacy ? KEY_DSA_CERT_V00 : KEY_DSA_CERT;
1.83 djm 1736: return 0;
1.92 djm 1737: case KEY_ECDSA:
1.97 djm 1738: if (legacy)
1739: fatal("%s: legacy ECDSA certificates are not supported",
1740: __func__);
1.92 djm 1741: k->cert = cert_new();
1742: k->type = KEY_ECDSA_CERT;
1743: return 0;
1.83 djm 1744: default:
1745: error("%s: key has incorrect type %s", __func__, key_type(k));
1746: return -1;
1747: }
1748: }
1749:
1750: /* Convert a KEY_RSA_CERT or KEY_DSA_CERT to their raw key equivalent */
1751: int
1752: key_drop_cert(Key *k)
1753: {
1754: switch (k->type) {
1.87 djm 1755: case KEY_RSA_CERT_V00:
1.83 djm 1756: case KEY_RSA_CERT:
1757: cert_free(k->cert);
1758: k->type = KEY_RSA;
1759: return 0;
1.87 djm 1760: case KEY_DSA_CERT_V00:
1.83 djm 1761: case KEY_DSA_CERT:
1762: cert_free(k->cert);
1763: k->type = KEY_DSA;
1764: return 0;
1.92 djm 1765: case KEY_ECDSA_CERT:
1766: cert_free(k->cert);
1767: k->type = KEY_ECDSA;
1768: return 0;
1.83 djm 1769: default:
1770: error("%s: key has incorrect type %s", __func__, key_type(k));
1771: return -1;
1772: }
1773: }
1774:
1.92 djm 1775: /*
1776: * Sign a KEY_RSA_CERT, KEY_DSA_CERT or KEY_ECDSA_CERT, (re-)generating
1777: * the signed certblob
1778: */
1.83 djm 1779: int
1780: key_certify(Key *k, Key *ca)
1781: {
1782: Buffer principals;
1783: u_char *ca_blob, *sig_blob, nonce[32];
1784: u_int i, ca_len, sig_len;
1785:
1786: if (k->cert == NULL) {
1787: error("%s: key lacks cert info", __func__);
1788: return -1;
1789: }
1790:
1791: if (!key_is_cert(k)) {
1792: error("%s: certificate has unknown type %d", __func__,
1793: k->cert->type);
1794: return -1;
1795: }
1796:
1.92 djm 1797: if (ca->type != KEY_RSA && ca->type != KEY_DSA &&
1798: ca->type != KEY_ECDSA) {
1.83 djm 1799: error("%s: CA key has unsupported type %s", __func__,
1800: key_type(ca));
1801: return -1;
1802: }
1803:
1804: key_to_blob(ca, &ca_blob, &ca_len);
1805:
1806: buffer_clear(&k->cert->certblob);
1807: buffer_put_cstring(&k->cert->certblob, key_ssh_name(k));
1808:
1.87 djm 1809: /* -v01 certs put nonce first */
1.96 djm 1810: arc4random_buf(&nonce, sizeof(nonce));
1811: if (!key_cert_is_legacy(k))
1.87 djm 1812: buffer_put_string(&k->cert->certblob, nonce, sizeof(nonce));
1813:
1.83 djm 1814: switch (k->type) {
1.87 djm 1815: case KEY_DSA_CERT_V00:
1.83 djm 1816: case KEY_DSA_CERT:
1817: buffer_put_bignum2(&k->cert->certblob, k->dsa->p);
1818: buffer_put_bignum2(&k->cert->certblob, k->dsa->q);
1819: buffer_put_bignum2(&k->cert->certblob, k->dsa->g);
1820: buffer_put_bignum2(&k->cert->certblob, k->dsa->pub_key);
1821: break;
1.92 djm 1822: case KEY_ECDSA_CERT:
1823: buffer_put_cstring(&k->cert->certblob,
1824: key_curve_nid_to_name(k->ecdsa_nid));
1825: buffer_put_ecpoint(&k->cert->certblob,
1826: EC_KEY_get0_group(k->ecdsa),
1827: EC_KEY_get0_public_key(k->ecdsa));
1828: break;
1.87 djm 1829: case KEY_RSA_CERT_V00:
1.83 djm 1830: case KEY_RSA_CERT:
1831: buffer_put_bignum2(&k->cert->certblob, k->rsa->e);
1832: buffer_put_bignum2(&k->cert->certblob, k->rsa->n);
1833: break;
1834: default:
1835: error("%s: key has incorrect type %s", __func__, key_type(k));
1836: buffer_clear(&k->cert->certblob);
1.103 ! djm 1837: free(ca_blob);
1.83 djm 1838: return -1;
1839: }
1840:
1.87 djm 1841: /* -v01 certs have a serial number next */
1.92 djm 1842: if (!key_cert_is_legacy(k))
1.87 djm 1843: buffer_put_int64(&k->cert->certblob, k->cert->serial);
1844:
1.83 djm 1845: buffer_put_int(&k->cert->certblob, k->cert->type);
1846: buffer_put_cstring(&k->cert->certblob, k->cert->key_id);
1847:
1848: buffer_init(&principals);
1849: for (i = 0; i < k->cert->nprincipals; i++)
1850: buffer_put_cstring(&principals, k->cert->principals[i]);
1851: buffer_put_string(&k->cert->certblob, buffer_ptr(&principals),
1852: buffer_len(&principals));
1853: buffer_free(&principals);
1854:
1855: buffer_put_int64(&k->cert->certblob, k->cert->valid_after);
1856: buffer_put_int64(&k->cert->certblob, k->cert->valid_before);
1857: buffer_put_string(&k->cert->certblob,
1.87 djm 1858: buffer_ptr(&k->cert->critical), buffer_len(&k->cert->critical));
1859:
1860: /* -v01 certs have non-critical options here */
1.92 djm 1861: if (!key_cert_is_legacy(k)) {
1.87 djm 1862: buffer_put_string(&k->cert->certblob,
1863: buffer_ptr(&k->cert->extensions),
1864: buffer_len(&k->cert->extensions));
1865: }
1866:
1867: /* -v00 certs put the nonce at the end */
1.92 djm 1868: if (key_cert_is_legacy(k))
1.87 djm 1869: buffer_put_string(&k->cert->certblob, nonce, sizeof(nonce));
1.83 djm 1870:
1871: buffer_put_string(&k->cert->certblob, NULL, 0); /* reserved */
1872: buffer_put_string(&k->cert->certblob, ca_blob, ca_len);
1.103 ! djm 1873: free(ca_blob);
1.83 djm 1874:
1875: /* Sign the whole mess */
1876: if (key_sign(ca, &sig_blob, &sig_len, buffer_ptr(&k->cert->certblob),
1877: buffer_len(&k->cert->certblob)) != 0) {
1878: error("%s: signature operation failed", __func__);
1879: buffer_clear(&k->cert->certblob);
1880: return -1;
1881: }
1882: /* Append signature and we are done */
1883: buffer_put_string(&k->cert->certblob, sig_blob, sig_len);
1.103 ! djm 1884: free(sig_blob);
1.83 djm 1885:
1886: return 0;
1887: }
1888:
1889: int
1890: key_cert_check_authority(const Key *k, int want_host, int require_principal,
1891: const char *name, const char **reason)
1892: {
1893: u_int i, principal_matches;
1894: time_t now = time(NULL);
1895:
1896: if (want_host) {
1897: if (k->cert->type != SSH2_CERT_TYPE_HOST) {
1898: *reason = "Certificate invalid: not a host certificate";
1899: return -1;
1900: }
1901: } else {
1902: if (k->cert->type != SSH2_CERT_TYPE_USER) {
1903: *reason = "Certificate invalid: not a user certificate";
1904: return -1;
1905: }
1906: }
1907: if (now < 0) {
1908: error("%s: system clock lies before epoch", __func__);
1909: *reason = "Certificate invalid: not yet valid";
1910: return -1;
1911: }
1912: if ((u_int64_t)now < k->cert->valid_after) {
1913: *reason = "Certificate invalid: not yet valid";
1914: return -1;
1915: }
1916: if ((u_int64_t)now >= k->cert->valid_before) {
1917: *reason = "Certificate invalid: expired";
1918: return -1;
1919: }
1920: if (k->cert->nprincipals == 0) {
1921: if (require_principal) {
1922: *reason = "Certificate lacks principal list";
1923: return -1;
1924: }
1.88 djm 1925: } else if (name != NULL) {
1.83 djm 1926: principal_matches = 0;
1927: for (i = 0; i < k->cert->nprincipals; i++) {
1928: if (strcmp(name, k->cert->principals[i]) == 0) {
1929: principal_matches = 1;
1930: break;
1931: }
1932: }
1933: if (!principal_matches) {
1934: *reason = "Certificate invalid: name is not a listed "
1935: "principal";
1936: return -1;
1937: }
1938: }
1939: return 0;
1.87 djm 1940: }
1941:
1942: int
1.100 djm 1943: key_cert_is_legacy(const Key *k)
1.87 djm 1944: {
1945: switch (k->type) {
1946: case KEY_DSA_CERT_V00:
1947: case KEY_RSA_CERT_V00:
1948: return 1;
1949: default:
1950: return 0;
1951: }
1.4 markus 1952: }
1.92 djm 1953:
1.93 djm 1954: /* XXX: these are really begging for a table-driven approach */
1.92 djm 1955: int
1956: key_curve_name_to_nid(const char *name)
1957: {
1958: if (strcmp(name, "nistp256") == 0)
1959: return NID_X9_62_prime256v1;
1960: else if (strcmp(name, "nistp384") == 0)
1961: return NID_secp384r1;
1962: else if (strcmp(name, "nistp521") == 0)
1963: return NID_secp521r1;
1964:
1965: debug("%s: unsupported EC curve name \"%.100s\"", __func__, name);
1966: return -1;
1967: }
1968:
1.93 djm 1969: u_int
1970: key_curve_nid_to_bits(int nid)
1971: {
1972: switch (nid) {
1973: case NID_X9_62_prime256v1:
1974: return 256;
1975: case NID_secp384r1:
1976: return 384;
1977: case NID_secp521r1:
1978: return 521;
1979: default:
1980: error("%s: unsupported EC curve nid %d", __func__, nid);
1981: return 0;
1982: }
1983: }
1984:
1.92 djm 1985: const char *
1986: key_curve_nid_to_name(int nid)
1987: {
1988: if (nid == NID_X9_62_prime256v1)
1989: return "nistp256";
1990: else if (nid == NID_secp384r1)
1991: return "nistp384";
1992: else if (nid == NID_secp521r1)
1993: return "nistp521";
1994:
1995: error("%s: unsupported EC curve nid %d", __func__, nid);
1996: return NULL;
1.93 djm 1997: }
1998:
1999: const EVP_MD *
2000: key_ec_nid_to_evpmd(int nid)
2001: {
2002: int kbits = key_curve_nid_to_bits(nid);
2003:
2004: if (kbits == 0)
2005: fatal("%s: invalid nid %d", __func__, nid);
2006: /* RFC5656 section 6.2.1 */
2007: if (kbits <= 256)
2008: return EVP_sha256();
2009: else if (kbits <= 384)
2010: return EVP_sha384();
2011: else
2012: return EVP_sha512();
1.92 djm 2013: }
2014:
2015: int
2016: key_ec_validate_public(const EC_GROUP *group, const EC_POINT *public)
2017: {
2018: BN_CTX *bnctx;
2019: EC_POINT *nq = NULL;
2020: BIGNUM *order, *x, *y, *tmp;
2021: int ret = -1;
2022:
2023: if ((bnctx = BN_CTX_new()) == NULL)
2024: fatal("%s: BN_CTX_new failed", __func__);
2025: BN_CTX_start(bnctx);
2026:
2027: /*
2028: * We shouldn't ever hit this case because bignum_get_ecpoint()
2029: * refuses to load GF2m points.
2030: */
2031: if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) !=
2032: NID_X9_62_prime_field) {
2033: error("%s: group is not a prime field", __func__);
2034: goto out;
2035: }
2036:
2037: /* Q != infinity */
2038: if (EC_POINT_is_at_infinity(group, public)) {
2039: error("%s: received degenerate public key (infinity)",
2040: __func__);
2041: goto out;
2042: }
2043:
2044: if ((x = BN_CTX_get(bnctx)) == NULL ||
2045: (y = BN_CTX_get(bnctx)) == NULL ||
2046: (order = BN_CTX_get(bnctx)) == NULL ||
2047: (tmp = BN_CTX_get(bnctx)) == NULL)
2048: fatal("%s: BN_CTX_get failed", __func__);
2049:
2050: /* log2(x) > log2(order)/2, log2(y) > log2(order)/2 */
2051: if (EC_GROUP_get_order(group, order, bnctx) != 1)
2052: fatal("%s: EC_GROUP_get_order failed", __func__);
2053: if (EC_POINT_get_affine_coordinates_GFp(group, public,
2054: x, y, bnctx) != 1)
2055: fatal("%s: EC_POINT_get_affine_coordinates_GFp", __func__);
2056: if (BN_num_bits(x) <= BN_num_bits(order) / 2) {
2057: error("%s: public key x coordinate too small: "
2058: "bits(x) = %d, bits(order)/2 = %d", __func__,
2059: BN_num_bits(x), BN_num_bits(order) / 2);
2060: goto out;
2061: }
2062: if (BN_num_bits(y) <= BN_num_bits(order) / 2) {
2063: error("%s: public key y coordinate too small: "
2064: "bits(y) = %d, bits(order)/2 = %d", __func__,
2065: BN_num_bits(x), BN_num_bits(order) / 2);
2066: goto out;
2067: }
2068:
2069: /* nQ == infinity (n == order of subgroup) */
2070: if ((nq = EC_POINT_new(group)) == NULL)
2071: fatal("%s: BN_CTX_tmp failed", __func__);
2072: if (EC_POINT_mul(group, nq, NULL, public, order, bnctx) != 1)
2073: fatal("%s: EC_GROUP_mul failed", __func__);
2074: if (EC_POINT_is_at_infinity(group, nq) != 1) {
2075: error("%s: received degenerate public key (nQ != infinity)",
2076: __func__);
2077: goto out;
2078: }
2079:
2080: /* x < order - 1, y < order - 1 */
2081: if (!BN_sub(tmp, order, BN_value_one()))
2082: fatal("%s: BN_sub failed", __func__);
2083: if (BN_cmp(x, tmp) >= 0) {
2084: error("%s: public key x coordinate >= group order - 1",
2085: __func__);
2086: goto out;
2087: }
2088: if (BN_cmp(y, tmp) >= 0) {
2089: error("%s: public key y coordinate >= group order - 1",
2090: __func__);
2091: goto out;
2092: }
2093: ret = 0;
2094: out:
2095: BN_CTX_free(bnctx);
2096: EC_POINT_free(nq);
2097: return ret;
2098: }
2099:
2100: int
2101: key_ec_validate_private(const EC_KEY *key)
2102: {
2103: BN_CTX *bnctx;
2104: BIGNUM *order, *tmp;
2105: int ret = -1;
2106:
2107: if ((bnctx = BN_CTX_new()) == NULL)
2108: fatal("%s: BN_CTX_new failed", __func__);
2109: BN_CTX_start(bnctx);
2110:
2111: if ((order = BN_CTX_get(bnctx)) == NULL ||
2112: (tmp = BN_CTX_get(bnctx)) == NULL)
2113: fatal("%s: BN_CTX_get failed", __func__);
2114:
2115: /* log2(private) > log2(order)/2 */
2116: if (EC_GROUP_get_order(EC_KEY_get0_group(key), order, bnctx) != 1)
2117: fatal("%s: EC_GROUP_get_order failed", __func__);
2118: if (BN_num_bits(EC_KEY_get0_private_key(key)) <=
2119: BN_num_bits(order) / 2) {
2120: error("%s: private key too small: "
2121: "bits(y) = %d, bits(order)/2 = %d", __func__,
2122: BN_num_bits(EC_KEY_get0_private_key(key)),
2123: BN_num_bits(order) / 2);
2124: goto out;
2125: }
2126:
2127: /* private < order - 1 */
2128: if (!BN_sub(tmp, order, BN_value_one()))
2129: fatal("%s: BN_sub failed", __func__);
2130: if (BN_cmp(EC_KEY_get0_private_key(key), tmp) >= 0) {
2131: error("%s: private key >= group order - 1", __func__);
2132: goto out;
2133: }
2134: ret = 0;
2135: out:
2136: BN_CTX_free(bnctx);
2137: return ret;
2138: }
2139:
2140: #if defined(DEBUG_KEXECDH) || defined(DEBUG_PK)
2141: void
2142: key_dump_ec_point(const EC_GROUP *group, const EC_POINT *point)
2143: {
2144: BIGNUM *x, *y;
2145: BN_CTX *bnctx;
2146:
2147: if (point == NULL) {
2148: fputs("point=(NULL)\n", stderr);
2149: return;
2150: }
2151: if ((bnctx = BN_CTX_new()) == NULL)
2152: fatal("%s: BN_CTX_new failed", __func__);
2153: BN_CTX_start(bnctx);
2154: if ((x = BN_CTX_get(bnctx)) == NULL || (y = BN_CTX_get(bnctx)) == NULL)
2155: fatal("%s: BN_CTX_get failed", __func__);
2156: if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) !=
2157: NID_X9_62_prime_field)
2158: fatal("%s: group is not a prime field", __func__);
2159: if (EC_POINT_get_affine_coordinates_GFp(group, point, x, y, bnctx) != 1)
2160: fatal("%s: EC_POINT_get_affine_coordinates_GFp", __func__);
2161: fputs("x=", stderr);
2162: BN_print_fp(stderr, x);
2163: fputs("\ny=", stderr);
2164: BN_print_fp(stderr, y);
2165: fputs("\n", stderr);
2166: BN_CTX_free(bnctx);
2167: }
2168:
2169: void
2170: key_dump_ec_key(const EC_KEY *key)
2171: {
2172: const BIGNUM *exponent;
2173:
2174: key_dump_ec_point(EC_KEY_get0_group(key), EC_KEY_get0_public_key(key));
2175: fputs("exponent=", stderr);
2176: if ((exponent = EC_KEY_get0_private_key(key)) == NULL)
2177: fputs("(NULL)", stderr);
2178: else
2179: BN_print_fp(stderr, EC_KEY_get0_private_key(key));
2180: fputs("\n", stderr);
2181: }
2182: #endif /* defined(DEBUG_KEXECDH) || defined(DEBUG_PK) */
2183:
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