Annotation of src/usr.bin/ssh/key.c, Revision 1.89
1.89 ! djm 1: /* $OpenBSD: key.c,v 1.88 2010/05/07 11:30:29 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;
1.3 markus 77: k->dsa = NULL;
78: k->rsa = NULL;
1.83 djm 79: k->cert = NULL;
1.1 markus 80: switch (k->type) {
1.12 markus 81: case KEY_RSA1:
1.1 markus 82: case KEY_RSA:
1.87 djm 83: case KEY_RSA_CERT_V00:
1.83 djm 84: case KEY_RSA_CERT:
1.38 markus 85: if ((rsa = RSA_new()) == NULL)
86: fatal("key_new: RSA_new failed");
87: if ((rsa->n = BN_new()) == NULL)
88: fatal("key_new: BN_new failed");
89: if ((rsa->e = BN_new()) == NULL)
90: fatal("key_new: BN_new failed");
1.1 markus 91: k->rsa = rsa;
92: break;
93: case KEY_DSA:
1.87 djm 94: case KEY_DSA_CERT_V00:
1.83 djm 95: case KEY_DSA_CERT:
1.38 markus 96: if ((dsa = DSA_new()) == NULL)
97: fatal("key_new: DSA_new failed");
98: if ((dsa->p = BN_new()) == NULL)
99: fatal("key_new: BN_new failed");
100: if ((dsa->q = BN_new()) == NULL)
101: fatal("key_new: BN_new failed");
102: if ((dsa->g = BN_new()) == NULL)
103: fatal("key_new: BN_new failed");
104: if ((dsa->pub_key = BN_new()) == NULL)
105: fatal("key_new: BN_new failed");
1.1 markus 106: k->dsa = dsa;
107: break;
1.12 markus 108: case KEY_UNSPEC:
1.1 markus 109: break;
110: default:
111: fatal("key_new: bad key type %d", k->type);
112: break;
113: }
1.83 djm 114:
115: if (key_is_cert(k))
116: k->cert = cert_new();
117:
1.1 markus 118: return k;
119: }
1.45 deraadt 120:
1.83 djm 121: void
122: key_add_private(Key *k)
1.12 markus 123: {
124: switch (k->type) {
125: case KEY_RSA1:
126: case KEY_RSA:
1.87 djm 127: case KEY_RSA_CERT_V00:
1.83 djm 128: case KEY_RSA_CERT:
1.38 markus 129: if ((k->rsa->d = BN_new()) == NULL)
130: fatal("key_new_private: BN_new failed");
131: if ((k->rsa->iqmp = BN_new()) == NULL)
132: fatal("key_new_private: BN_new failed");
133: if ((k->rsa->q = BN_new()) == NULL)
134: fatal("key_new_private: BN_new failed");
135: if ((k->rsa->p = BN_new()) == NULL)
136: fatal("key_new_private: BN_new failed");
137: if ((k->rsa->dmq1 = BN_new()) == NULL)
138: fatal("key_new_private: BN_new failed");
139: if ((k->rsa->dmp1 = BN_new()) == NULL)
140: fatal("key_new_private: BN_new failed");
1.12 markus 141: break;
142: case KEY_DSA:
1.87 djm 143: case KEY_DSA_CERT_V00:
1.83 djm 144: case KEY_DSA_CERT:
1.38 markus 145: if ((k->dsa->priv_key = BN_new()) == NULL)
146: fatal("key_new_private: BN_new failed");
1.12 markus 147: break;
148: case KEY_UNSPEC:
149: break;
150: default:
151: break;
152: }
1.83 djm 153: }
154:
155: Key *
156: key_new_private(int type)
157: {
158: Key *k = key_new(type);
159:
160: key_add_private(k);
1.12 markus 161: return k;
162: }
1.45 deraadt 163:
1.83 djm 164: static void
165: cert_free(struct KeyCert *cert)
166: {
167: u_int i;
168:
169: buffer_free(&cert->certblob);
1.87 djm 170: buffer_free(&cert->critical);
171: buffer_free(&cert->extensions);
1.83 djm 172: if (cert->key_id != NULL)
173: xfree(cert->key_id);
174: for (i = 0; i < cert->nprincipals; i++)
175: xfree(cert->principals[i]);
176: if (cert->principals != NULL)
177: xfree(cert->principals);
178: if (cert->signature_key != NULL)
179: key_free(cert->signature_key);
180: }
181:
1.1 markus 182: void
183: key_free(Key *k)
184: {
1.60 djm 185: if (k == NULL)
1.62 deraadt 186: fatal("key_free: key is NULL");
1.1 markus 187: switch (k->type) {
1.12 markus 188: case KEY_RSA1:
1.1 markus 189: case KEY_RSA:
1.87 djm 190: case KEY_RSA_CERT_V00:
1.83 djm 191: case KEY_RSA_CERT:
1.1 markus 192: if (k->rsa != NULL)
193: RSA_free(k->rsa);
194: k->rsa = NULL;
195: break;
196: case KEY_DSA:
1.87 djm 197: case KEY_DSA_CERT_V00:
1.83 djm 198: case KEY_DSA_CERT:
1.1 markus 199: if (k->dsa != NULL)
200: DSA_free(k->dsa);
201: k->dsa = NULL;
202: break;
1.12 markus 203: case KEY_UNSPEC:
204: break;
1.1 markus 205: default:
206: fatal("key_free: bad key type %d", k->type);
207: break;
208: }
1.83 djm 209: if (key_is_cert(k)) {
210: if (k->cert != NULL)
211: cert_free(k->cert);
212: k->cert = NULL;
213: }
214:
1.1 markus 215: xfree(k);
216: }
1.55 jakob 217:
1.83 djm 218: static int
219: cert_compare(struct KeyCert *a, struct KeyCert *b)
220: {
221: if (a == NULL && b == NULL)
222: return 1;
223: if (a == NULL || b == NULL)
224: return 0;
225: if (buffer_len(&a->certblob) != buffer_len(&b->certblob))
226: return 0;
1.89 ! djm 227: if (timing_safe_cmp(buffer_ptr(&a->certblob), buffer_ptr(&b->certblob),
1.83 djm 228: buffer_len(&a->certblob)) != 0)
229: return 0;
230: return 1;
231: }
232:
233: /*
234: * Compare public portions of key only, allowing comparisons between
235: * certificates and plain keys too.
236: */
1.1 markus 237: int
1.83 djm 238: key_equal_public(const Key *a, const Key *b)
1.1 markus 239: {
1.83 djm 240: if (a == NULL || b == NULL ||
241: key_type_plain(a->type) != key_type_plain(b->type))
1.1 markus 242: return 0;
1.83 djm 243:
1.1 markus 244: switch (a->type) {
1.12 markus 245: case KEY_RSA1:
1.87 djm 246: case KEY_RSA_CERT_V00:
1.83 djm 247: case KEY_RSA_CERT:
1.1 markus 248: case KEY_RSA:
249: return a->rsa != NULL && b->rsa != NULL &&
250: BN_cmp(a->rsa->e, b->rsa->e) == 0 &&
251: BN_cmp(a->rsa->n, b->rsa->n) == 0;
1.87 djm 252: case KEY_DSA_CERT_V00:
1.83 djm 253: case KEY_DSA_CERT:
1.1 markus 254: case KEY_DSA:
255: return a->dsa != NULL && b->dsa != NULL &&
256: BN_cmp(a->dsa->p, b->dsa->p) == 0 &&
257: BN_cmp(a->dsa->q, b->dsa->q) == 0 &&
258: BN_cmp(a->dsa->g, b->dsa->g) == 0 &&
259: BN_cmp(a->dsa->pub_key, b->dsa->pub_key) == 0;
260: default:
1.3 markus 261: fatal("key_equal: bad key type %d", a->type);
1.1 markus 262: }
1.78 stevesk 263: /* NOTREACHED */
1.1 markus 264: }
265:
1.83 djm 266: int
267: key_equal(const Key *a, const Key *b)
268: {
269: if (a == NULL || b == NULL || a->type != b->type)
270: return 0;
271: if (key_is_cert(a)) {
272: if (!cert_compare(a->cert, b->cert))
273: return 0;
274: }
275: return key_equal_public(a, b);
276: }
277:
1.52 jakob 278: u_char*
1.83 djm 279: key_fingerprint_raw(Key *k, enum fp_type dgst_type, u_int *dgst_raw_length)
1.1 markus 280: {
1.41 markus 281: const EVP_MD *md = NULL;
1.21 markus 282: EVP_MD_CTX ctx;
1.13 markus 283: u_char *blob = NULL;
1.19 jakob 284: u_char *retval = NULL;
1.40 markus 285: u_int len = 0;
1.83 djm 286: int nlen, elen, otype;
1.1 markus 287:
1.19 jakob 288: *dgst_raw_length = 0;
289:
1.21 markus 290: switch (dgst_type) {
291: case SSH_FP_MD5:
292: md = EVP_md5();
293: break;
294: case SSH_FP_SHA1:
295: md = EVP_sha1();
296: break;
297: default:
298: fatal("key_fingerprint_raw: bad digest type %d",
299: dgst_type);
300: }
1.1 markus 301: switch (k->type) {
1.12 markus 302: case KEY_RSA1:
1.1 markus 303: nlen = BN_num_bytes(k->rsa->n);
304: elen = BN_num_bytes(k->rsa->e);
305: len = nlen + elen;
1.3 markus 306: blob = xmalloc(len);
307: BN_bn2bin(k->rsa->n, blob);
308: BN_bn2bin(k->rsa->e, blob + nlen);
1.1 markus 309: break;
310: case KEY_DSA:
1.12 markus 311: case KEY_RSA:
312: key_to_blob(k, &blob, &len);
313: break;
1.87 djm 314: case KEY_DSA_CERT_V00:
315: case KEY_RSA_CERT_V00:
1.83 djm 316: case KEY_DSA_CERT:
317: case KEY_RSA_CERT:
318: /* We want a fingerprint of the _key_ not of the cert */
319: otype = k->type;
320: k->type = key_type_plain(k->type);
321: key_to_blob(k, &blob, &len);
322: k->type = otype;
323: break;
1.12 markus 324: case KEY_UNSPEC:
325: return retval;
1.1 markus 326: default:
1.19 jakob 327: fatal("key_fingerprint_raw: bad key type %d", k->type);
1.1 markus 328: break;
329: }
1.3 markus 330: if (blob != NULL) {
1.19 jakob 331: retval = xmalloc(EVP_MAX_MD_SIZE);
1.8 markus 332: EVP_DigestInit(&ctx, md);
333: EVP_DigestUpdate(&ctx, blob, len);
1.39 markus 334: EVP_DigestFinal(&ctx, retval, dgst_raw_length);
1.3 markus 335: memset(blob, 0, len);
336: xfree(blob);
1.19 jakob 337: } else {
338: fatal("key_fingerprint_raw: blob is null");
1.1 markus 339: }
1.19 jakob 340: return retval;
341: }
342:
1.46 deraadt 343: static char *
344: key_fingerprint_hex(u_char *dgst_raw, u_int dgst_raw_len)
1.19 jakob 345: {
346: char *retval;
1.58 djm 347: u_int i;
1.19 jakob 348:
1.63 djm 349: retval = xcalloc(1, dgst_raw_len * 3 + 1);
1.36 deraadt 350: for (i = 0; i < dgst_raw_len; i++) {
1.19 jakob 351: char hex[4];
352: snprintf(hex, sizeof(hex), "%02x:", dgst_raw[i]);
1.54 avsm 353: strlcat(retval, hex, dgst_raw_len * 3 + 1);
1.19 jakob 354: }
1.54 avsm 355:
356: /* Remove the trailing ':' character */
1.19 jakob 357: retval[(dgst_raw_len * 3) - 1] = '\0';
358: return retval;
359: }
360:
1.46 deraadt 361: static char *
362: key_fingerprint_bubblebabble(u_char *dgst_raw, u_int dgst_raw_len)
1.19 jakob 363: {
364: char vowels[] = { 'a', 'e', 'i', 'o', 'u', 'y' };
365: char consonants[] = { 'b', 'c', 'd', 'f', 'g', 'h', 'k', 'l', 'm',
366: 'n', 'p', 'r', 's', 't', 'v', 'z', 'x' };
1.20 jakob 367: u_int i, j = 0, rounds, seed = 1;
1.19 jakob 368: char *retval;
369:
370: rounds = (dgst_raw_len / 2) + 1;
1.63 djm 371: retval = xcalloc((rounds * 6), sizeof(char));
1.20 jakob 372: retval[j++] = 'x';
373: for (i = 0; i < rounds; i++) {
1.19 jakob 374: u_int idx0, idx1, idx2, idx3, idx4;
1.20 jakob 375: if ((i + 1 < rounds) || (dgst_raw_len % 2 != 0)) {
376: idx0 = (((((u_int)(dgst_raw[2 * i])) >> 6) & 3) +
1.19 jakob 377: seed) % 6;
1.20 jakob 378: idx1 = (((u_int)(dgst_raw[2 * i])) >> 2) & 15;
379: idx2 = ((((u_int)(dgst_raw[2 * i])) & 3) +
1.19 jakob 380: (seed / 6)) % 6;
1.20 jakob 381: retval[j++] = vowels[idx0];
382: retval[j++] = consonants[idx1];
383: retval[j++] = vowels[idx2];
384: if ((i + 1) < rounds) {
385: idx3 = (((u_int)(dgst_raw[(2 * i) + 1])) >> 4) & 15;
386: idx4 = (((u_int)(dgst_raw[(2 * i) + 1]))) & 15;
387: retval[j++] = consonants[idx3];
388: retval[j++] = '-';
389: retval[j++] = consonants[idx4];
1.19 jakob 390: seed = ((seed * 5) +
1.20 jakob 391: ((((u_int)(dgst_raw[2 * i])) * 7) +
392: ((u_int)(dgst_raw[(2 * i) + 1])))) % 36;
1.19 jakob 393: }
394: } else {
395: idx0 = seed % 6;
396: idx1 = 16;
397: idx2 = seed / 6;
1.20 jakob 398: retval[j++] = vowels[idx0];
399: retval[j++] = consonants[idx1];
400: retval[j++] = vowels[idx2];
1.19 jakob 401: }
402: }
1.20 jakob 403: retval[j++] = 'x';
404: retval[j++] = '\0';
1.19 jakob 405: return retval;
406: }
407:
1.70 grunk 408: /*
409: * Draw an ASCII-Art representing the fingerprint so human brain can
410: * profit from its built-in pattern recognition ability.
411: * This technique is called "random art" and can be found in some
412: * scientific publications like this original paper:
413: *
414: * "Hash Visualization: a New Technique to improve Real-World Security",
415: * Perrig A. and Song D., 1999, International Workshop on Cryptographic
416: * Techniques and E-Commerce (CrypTEC '99)
417: * sparrow.ece.cmu.edu/~adrian/projects/validation/validation.pdf
418: *
419: * The subject came up in a talk by Dan Kaminsky, too.
420: *
421: * If you see the picture is different, the key is different.
422: * If the picture looks the same, you still know nothing.
423: *
424: * The algorithm used here is a worm crawling over a discrete plane,
425: * leaving a trace (augmenting the field) everywhere it goes.
426: * Movement is taken from dgst_raw 2bit-wise. Bumping into walls
427: * makes the respective movement vector be ignored for this turn.
428: * Graphs are not unambiguous, because circles in graphs can be
429: * walked in either direction.
430: */
1.74 grunk 431:
432: /*
433: * Field sizes for the random art. Have to be odd, so the starting point
434: * can be in the exact middle of the picture, and FLDBASE should be >=8 .
435: * Else pictures would be too dense, and drawing the frame would
436: * fail, too, because the key type would not fit in anymore.
437: */
438: #define FLDBASE 8
439: #define FLDSIZE_Y (FLDBASE + 1)
440: #define FLDSIZE_X (FLDBASE * 2 + 1)
1.70 grunk 441: static char *
1.74 grunk 442: key_fingerprint_randomart(u_char *dgst_raw, u_int dgst_raw_len, const Key *k)
1.70 grunk 443: {
444: /*
445: * Chars to be used after each other every time the worm
446: * intersects with itself. Matter of taste.
447: */
1.75 grunk 448: char *augmentation_string = " .o+=*BOX@%&#/^SE";
1.70 grunk 449: char *retval, *p;
1.71 otto 450: u_char field[FLDSIZE_X][FLDSIZE_Y];
1.70 grunk 451: u_int i, b;
452: int x, y;
1.72 grunk 453: size_t len = strlen(augmentation_string) - 1;
1.70 grunk 454:
455: retval = xcalloc(1, (FLDSIZE_X + 3) * (FLDSIZE_Y + 2));
456:
457: /* initialize field */
1.71 otto 458: memset(field, 0, FLDSIZE_X * FLDSIZE_Y * sizeof(char));
1.70 grunk 459: x = FLDSIZE_X / 2;
460: y = FLDSIZE_Y / 2;
461:
462: /* process raw key */
463: for (i = 0; i < dgst_raw_len; i++) {
464: int input;
465: /* each byte conveys four 2-bit move commands */
466: input = dgst_raw[i];
467: for (b = 0; b < 4; b++) {
468: /* evaluate 2 bit, rest is shifted later */
469: x += (input & 0x1) ? 1 : -1;
470: y += (input & 0x2) ? 1 : -1;
471:
472: /* assure we are still in bounds */
473: x = MAX(x, 0);
474: y = MAX(y, 0);
475: x = MIN(x, FLDSIZE_X - 1);
476: y = MIN(y, FLDSIZE_Y - 1);
477:
478: /* augment the field */
1.79 grunk 479: if (field[x][y] < len - 2)
480: field[x][y]++;
1.70 grunk 481: input = input >> 2;
482: }
483: }
1.75 grunk 484:
485: /* mark starting point and end point*/
486: field[FLDSIZE_X / 2][FLDSIZE_Y / 2] = len - 1;
487: field[x][y] = len;
1.70 grunk 488:
489: /* fill in retval */
1.77 otto 490: snprintf(retval, FLDSIZE_X, "+--[%4s %4u]", key_type(k), key_size(k));
1.74 grunk 491: p = strchr(retval, '\0');
1.70 grunk 492:
493: /* output upper border */
1.77 otto 494: for (i = p - retval - 1; i < FLDSIZE_X; i++)
1.70 grunk 495: *p++ = '-';
496: *p++ = '+';
497: *p++ = '\n';
498:
499: /* output content */
500: for (y = 0; y < FLDSIZE_Y; y++) {
501: *p++ = '|';
502: for (x = 0; x < FLDSIZE_X; x++)
1.72 grunk 503: *p++ = augmentation_string[MIN(field[x][y], len)];
1.70 grunk 504: *p++ = '|';
505: *p++ = '\n';
506: }
507:
508: /* output lower border */
509: *p++ = '+';
510: for (i = 0; i < FLDSIZE_X; i++)
511: *p++ = '-';
512: *p++ = '+';
513:
514: return retval;
515: }
516:
1.46 deraadt 517: char *
1.83 djm 518: key_fingerprint(Key *k, enum fp_type dgst_type, enum fp_rep dgst_rep)
1.19 jakob 519: {
1.23 markus 520: char *retval = NULL;
1.19 jakob 521: u_char *dgst_raw;
1.39 markus 522: u_int dgst_raw_len;
1.36 deraadt 523:
1.19 jakob 524: dgst_raw = key_fingerprint_raw(k, dgst_type, &dgst_raw_len);
525: if (!dgst_raw)
1.22 markus 526: fatal("key_fingerprint: null from key_fingerprint_raw()");
1.35 deraadt 527: switch (dgst_rep) {
1.19 jakob 528: case SSH_FP_HEX:
529: retval = key_fingerprint_hex(dgst_raw, dgst_raw_len);
530: break;
531: case SSH_FP_BUBBLEBABBLE:
532: retval = key_fingerprint_bubblebabble(dgst_raw, dgst_raw_len);
1.70 grunk 533: break;
534: case SSH_FP_RANDOMART:
1.74 grunk 535: retval = key_fingerprint_randomart(dgst_raw, dgst_raw_len, k);
1.19 jakob 536: break;
537: default:
1.80 stevesk 538: fatal("key_fingerprint: bad digest representation %d",
1.19 jakob 539: dgst_rep);
540: break;
541: }
542: memset(dgst_raw, 0, dgst_raw_len);
543: xfree(dgst_raw);
1.1 markus 544: return retval;
545: }
546:
547: /*
548: * Reads a multiple-precision integer in decimal from the buffer, and advances
549: * the pointer. The integer must already be initialized. This function is
550: * permitted to modify the buffer. This leaves *cpp to point just beyond the
551: * last processed (and maybe modified) character. Note that this may modify
552: * the buffer containing the number.
553: */
1.27 itojun 554: static int
1.1 markus 555: read_bignum(char **cpp, BIGNUM * value)
556: {
557: char *cp = *cpp;
558: int old;
559:
560: /* Skip any leading whitespace. */
561: for (; *cp == ' ' || *cp == '\t'; cp++)
562: ;
563:
564: /* Check that it begins with a decimal digit. */
565: if (*cp < '0' || *cp > '9')
566: return 0;
567:
568: /* Save starting position. */
569: *cpp = cp;
570:
571: /* Move forward until all decimal digits skipped. */
572: for (; *cp >= '0' && *cp <= '9'; cp++)
573: ;
574:
575: /* Save the old terminating character, and replace it by \0. */
576: old = *cp;
577: *cp = 0;
578:
579: /* Parse the number. */
580: if (BN_dec2bn(&value, *cpp) == 0)
581: return 0;
582:
583: /* Restore old terminating character. */
584: *cp = old;
585:
586: /* Move beyond the number and return success. */
587: *cpp = cp;
588: return 1;
589: }
1.45 deraadt 590:
1.27 itojun 591: static int
1.1 markus 592: write_bignum(FILE *f, BIGNUM *num)
593: {
594: char *buf = BN_bn2dec(num);
595: if (buf == NULL) {
596: error("write_bignum: BN_bn2dec() failed");
597: return 0;
598: }
599: fprintf(f, " %s", buf);
1.33 markus 600: OPENSSL_free(buf);
1.1 markus 601: return 1;
602: }
1.12 markus 603:
1.32 markus 604: /* returns 1 ok, -1 error */
1.12 markus 605: int
1.3 markus 606: key_read(Key *ret, char **cpp)
1.1 markus 607: {
1.3 markus 608: Key *k;
1.12 markus 609: int success = -1;
610: char *cp, *space;
611: int len, n, type;
612: u_int bits;
1.13 markus 613: u_char *blob;
1.3 markus 614:
615: cp = *cpp;
616:
1.35 deraadt 617: switch (ret->type) {
1.12 markus 618: case KEY_RSA1:
1.3 markus 619: /* Get number of bits. */
620: if (*cp < '0' || *cp > '9')
1.12 markus 621: return -1; /* Bad bit count... */
1.3 markus 622: for (bits = 0; *cp >= '0' && *cp <= '9'; cp++)
623: bits = 10 * bits + *cp - '0';
1.1 markus 624: if (bits == 0)
1.12 markus 625: return -1;
1.3 markus 626: *cpp = cp;
1.1 markus 627: /* Get public exponent, public modulus. */
628: if (!read_bignum(cpp, ret->rsa->e))
1.12 markus 629: return -1;
1.1 markus 630: if (!read_bignum(cpp, ret->rsa->n))
1.12 markus 631: return -1;
1.82 dtucker 632: /* validate the claimed number of bits */
633: if ((u_int)BN_num_bits(ret->rsa->n) != bits) {
634: verbose("key_read: claimed key size %d does not match "
635: "actual %d", bits, BN_num_bits(ret->rsa->n));
636: return -1;
637: }
1.12 markus 638: success = 1;
1.1 markus 639: break;
1.12 markus 640: case KEY_UNSPEC:
641: case KEY_RSA:
1.1 markus 642: case KEY_DSA:
1.87 djm 643: case KEY_DSA_CERT_V00:
644: case KEY_RSA_CERT_V00:
1.83 djm 645: case KEY_DSA_CERT:
646: case KEY_RSA_CERT:
1.12 markus 647: space = strchr(cp, ' ');
648: if (space == NULL) {
1.50 markus 649: debug3("key_read: missing whitespace");
1.12 markus 650: return -1;
651: }
652: *space = '\0';
653: type = key_type_from_name(cp);
654: *space = ' ';
655: if (type == KEY_UNSPEC) {
1.50 markus 656: debug3("key_read: missing keytype");
1.12 markus 657: return -1;
658: }
659: cp = space+1;
660: if (*cp == '\0') {
661: debug3("key_read: short string");
662: return -1;
663: }
664: if (ret->type == KEY_UNSPEC) {
665: ret->type = type;
666: } else if (ret->type != type) {
667: /* is a key, but different type */
668: debug3("key_read: type mismatch");
1.32 markus 669: return -1;
1.12 markus 670: }
1.3 markus 671: len = 2*strlen(cp);
672: blob = xmalloc(len);
673: n = uudecode(cp, blob, len);
1.6 markus 674: if (n < 0) {
1.7 markus 675: error("key_read: uudecode %s failed", cp);
1.34 markus 676: xfree(blob);
1.12 markus 677: return -1;
1.6 markus 678: }
1.53 markus 679: k = key_from_blob(blob, (u_int)n);
1.34 markus 680: xfree(blob);
1.7 markus 681: if (k == NULL) {
1.12 markus 682: error("key_read: key_from_blob %s failed", cp);
683: return -1;
1.7 markus 684: }
1.12 markus 685: if (k->type != type) {
686: error("key_read: type mismatch: encoding error");
687: key_free(k);
688: return -1;
689: }
690: /*XXXX*/
1.83 djm 691: if (key_is_cert(ret)) {
692: if (!key_is_cert(k)) {
693: error("key_read: loaded key is not a cert");
694: key_free(k);
695: return -1;
696: }
697: if (ret->cert != NULL)
698: cert_free(ret->cert);
699: ret->cert = k->cert;
700: k->cert = NULL;
701: }
702: if (key_type_plain(ret->type) == KEY_RSA) {
1.12 markus 703: if (ret->rsa != NULL)
704: RSA_free(ret->rsa);
705: ret->rsa = k->rsa;
706: k->rsa = NULL;
707: #ifdef DEBUG_PK
708: RSA_print_fp(stderr, ret->rsa, 8);
709: #endif
1.83 djm 710: }
711: if (key_type_plain(ret->type) == KEY_DSA) {
1.12 markus 712: if (ret->dsa != NULL)
713: DSA_free(ret->dsa);
714: ret->dsa = k->dsa;
715: k->dsa = NULL;
716: #ifdef DEBUG_PK
717: DSA_print_fp(stderr, ret->dsa, 8);
718: #endif
719: }
1.83 djm 720: success = 1;
1.12 markus 721: /*XXXX*/
1.34 markus 722: key_free(k);
1.12 markus 723: if (success != 1)
724: break;
1.7 markus 725: /* advance cp: skip whitespace and data */
726: while (*cp == ' ' || *cp == '\t')
727: cp++;
728: while (*cp != '\0' && *cp != ' ' && *cp != '\t')
729: cp++;
730: *cpp = cp;
1.1 markus 731: break;
732: default:
1.3 markus 733: fatal("key_read: bad key type: %d", ret->type);
1.1 markus 734: break;
735: }
1.12 markus 736: return success;
1.1 markus 737: }
1.45 deraadt 738:
1.1 markus 739: int
1.55 jakob 740: key_write(const Key *key, FILE *f)
1.1 markus 741: {
1.40 markus 742: int n, success = 0;
743: u_int len, bits = 0;
1.49 markus 744: u_char *blob;
745: char *uu;
1.1 markus 746:
1.83 djm 747: if (key_is_cert(key)) {
748: if (key->cert == NULL) {
749: error("%s: no cert data", __func__);
750: return 0;
751: }
752: if (buffer_len(&key->cert->certblob) == 0) {
753: error("%s: no signed certificate blob", __func__);
754: return 0;
755: }
756: }
757:
758: switch (key->type) {
759: case KEY_RSA1:
760: if (key->rsa == NULL)
761: return 0;
1.1 markus 762: /* size of modulus 'n' */
763: bits = BN_num_bits(key->rsa->n);
764: fprintf(f, "%u", bits);
765: if (write_bignum(f, key->rsa->e) &&
1.83 djm 766: write_bignum(f, key->rsa->n))
767: return 1;
768: error("key_write: failed for RSA key");
769: return 0;
770: case KEY_DSA:
1.87 djm 771: case KEY_DSA_CERT_V00:
1.83 djm 772: case KEY_DSA_CERT:
773: if (key->dsa == NULL)
774: return 0;
775: break;
776: case KEY_RSA:
1.87 djm 777: case KEY_RSA_CERT_V00:
1.83 djm 778: case KEY_RSA_CERT:
779: if (key->rsa == NULL)
780: return 0;
781: break;
782: default:
783: return 0;
784: }
785:
786: key_to_blob(key, &blob, &len);
787: uu = xmalloc(2*len);
788: n = uuencode(blob, len, uu, 2*len);
789: if (n > 0) {
790: fprintf(f, "%s %s", key_ssh_name(key), uu);
791: success = 1;
1.1 markus 792: }
1.83 djm 793: xfree(blob);
794: xfree(uu);
795:
1.1 markus 796: return success;
797: }
1.45 deraadt 798:
1.55 jakob 799: const char *
800: key_type(const Key *k)
1.4 markus 801: {
802: switch (k->type) {
1.12 markus 803: case KEY_RSA1:
804: return "RSA1";
1.4 markus 805: case KEY_RSA:
806: return "RSA";
807: case KEY_DSA:
808: return "DSA";
1.87 djm 809: case KEY_RSA_CERT_V00:
810: return "RSA-CERT-V00";
811: case KEY_DSA_CERT_V00:
812: return "DSA-CERT-V00";
1.83 djm 813: case KEY_RSA_CERT:
814: return "RSA-CERT";
815: case KEY_DSA_CERT:
816: return "DSA-CERT";
1.4 markus 817: }
818: return "unknown";
1.86 stevesk 819: }
820:
821: const char *
822: key_cert_type(const Key *k)
823: {
824: switch (k->cert->type) {
825: case SSH2_CERT_TYPE_USER:
826: return "user";
827: case SSH2_CERT_TYPE_HOST:
828: return "host";
829: default:
830: return "unknown";
831: }
1.10 markus 832: }
1.45 deraadt 833:
1.55 jakob 834: const char *
835: key_ssh_name(const Key *k)
1.12 markus 836: {
837: switch (k->type) {
838: case KEY_RSA:
839: return "ssh-rsa";
840: case KEY_DSA:
841: return "ssh-dss";
1.87 djm 842: case KEY_RSA_CERT_V00:
843: return "ssh-rsa-cert-v00@openssh.com";
844: case KEY_DSA_CERT_V00:
845: return "ssh-dss-cert-v00@openssh.com";
1.83 djm 846: case KEY_RSA_CERT:
1.87 djm 847: return "ssh-rsa-cert-v01@openssh.com";
1.83 djm 848: case KEY_DSA_CERT:
1.87 djm 849: return "ssh-dss-cert-v01@openssh.com";
1.12 markus 850: }
851: return "ssh-unknown";
852: }
1.45 deraadt 853:
1.12 markus 854: u_int
1.55 jakob 855: key_size(const Key *k)
1.35 deraadt 856: {
1.10 markus 857: switch (k->type) {
1.12 markus 858: case KEY_RSA1:
1.10 markus 859: case KEY_RSA:
1.87 djm 860: case KEY_RSA_CERT_V00:
1.83 djm 861: case KEY_RSA_CERT:
1.10 markus 862: return BN_num_bits(k->rsa->n);
863: case KEY_DSA:
1.87 djm 864: case KEY_DSA_CERT_V00:
1.83 djm 865: case KEY_DSA_CERT:
1.10 markus 866: return BN_num_bits(k->dsa->p);
867: }
868: return 0;
1.12 markus 869: }
870:
1.27 itojun 871: static RSA *
1.13 markus 872: rsa_generate_private_key(u_int bits)
1.12 markus 873: {
1.17 stevesk 874: RSA *private;
1.61 deraadt 875:
1.81 markus 876: private = RSA_generate_key(bits, RSA_F4, NULL, NULL);
1.17 stevesk 877: if (private == NULL)
878: fatal("rsa_generate_private_key: key generation failed.");
879: return private;
1.12 markus 880: }
881:
1.27 itojun 882: static DSA*
1.13 markus 883: dsa_generate_private_key(u_int bits)
1.12 markus 884: {
885: DSA *private = DSA_generate_parameters(bits, NULL, 0, NULL, NULL, NULL, NULL);
1.61 deraadt 886:
1.12 markus 887: if (private == NULL)
888: fatal("dsa_generate_private_key: DSA_generate_parameters failed");
889: if (!DSA_generate_key(private))
1.17 stevesk 890: fatal("dsa_generate_private_key: DSA_generate_key failed.");
891: if (private == NULL)
892: fatal("dsa_generate_private_key: NULL.");
1.12 markus 893: return private;
894: }
895:
896: Key *
1.13 markus 897: key_generate(int type, u_int bits)
1.12 markus 898: {
899: Key *k = key_new(KEY_UNSPEC);
900: switch (type) {
1.17 stevesk 901: case KEY_DSA:
1.12 markus 902: k->dsa = dsa_generate_private_key(bits);
903: break;
904: case KEY_RSA:
905: case KEY_RSA1:
906: k->rsa = rsa_generate_private_key(bits);
907: break;
1.87 djm 908: case KEY_RSA_CERT_V00:
909: case KEY_DSA_CERT_V00:
1.83 djm 910: case KEY_RSA_CERT:
911: case KEY_DSA_CERT:
912: fatal("key_generate: cert keys cannot be generated directly");
1.12 markus 913: default:
1.17 stevesk 914: fatal("key_generate: unknown type %d", type);
1.12 markus 915: }
1.17 stevesk 916: k->type = type;
1.12 markus 917: return k;
918: }
919:
1.83 djm 920: void
921: key_cert_copy(const Key *from_key, struct Key *to_key)
922: {
923: u_int i;
924: const struct KeyCert *from;
925: struct KeyCert *to;
926:
927: if (to_key->cert != NULL) {
928: cert_free(to_key->cert);
929: to_key->cert = NULL;
930: }
931:
932: if ((from = from_key->cert) == NULL)
933: return;
934:
935: to = to_key->cert = cert_new();
936:
937: buffer_append(&to->certblob, buffer_ptr(&from->certblob),
938: buffer_len(&from->certblob));
939:
1.87 djm 940: buffer_append(&to->critical,
941: buffer_ptr(&from->critical), buffer_len(&from->critical));
942: buffer_append(&to->extensions,
943: buffer_ptr(&from->extensions), buffer_len(&from->extensions));
1.83 djm 944:
1.87 djm 945: to->serial = from->serial;
1.83 djm 946: to->type = from->type;
947: to->key_id = from->key_id == NULL ? NULL : xstrdup(from->key_id);
948: to->valid_after = from->valid_after;
949: to->valid_before = from->valid_before;
950: to->signature_key = from->signature_key == NULL ?
951: NULL : key_from_private(from->signature_key);
952:
953: to->nprincipals = from->nprincipals;
954: if (to->nprincipals > CERT_MAX_PRINCIPALS)
955: fatal("%s: nprincipals (%u) > CERT_MAX_PRINCIPALS (%u)",
956: __func__, to->nprincipals, CERT_MAX_PRINCIPALS);
957: if (to->nprincipals > 0) {
958: to->principals = xcalloc(from->nprincipals,
959: sizeof(*to->principals));
960: for (i = 0; i < to->nprincipals; i++)
961: to->principals[i] = xstrdup(from->principals[i]);
962: }
963: }
964:
1.12 markus 965: Key *
1.55 jakob 966: key_from_private(const Key *k)
1.12 markus 967: {
968: Key *n = NULL;
969: switch (k->type) {
1.17 stevesk 970: case KEY_DSA:
1.87 djm 971: case KEY_DSA_CERT_V00:
1.83 djm 972: case KEY_DSA_CERT:
1.12 markus 973: n = key_new(k->type);
1.68 markus 974: if ((BN_copy(n->dsa->p, k->dsa->p) == NULL) ||
975: (BN_copy(n->dsa->q, k->dsa->q) == NULL) ||
976: (BN_copy(n->dsa->g, k->dsa->g) == NULL) ||
977: (BN_copy(n->dsa->pub_key, k->dsa->pub_key) == NULL))
978: fatal("key_from_private: BN_copy failed");
1.12 markus 979: break;
980: case KEY_RSA:
981: case KEY_RSA1:
1.87 djm 982: case KEY_RSA_CERT_V00:
1.83 djm 983: case KEY_RSA_CERT:
1.12 markus 984: n = key_new(k->type);
1.68 markus 985: if ((BN_copy(n->rsa->n, k->rsa->n) == NULL) ||
986: (BN_copy(n->rsa->e, k->rsa->e) == NULL))
987: fatal("key_from_private: BN_copy failed");
1.12 markus 988: break;
989: default:
1.17 stevesk 990: fatal("key_from_private: unknown type %d", k->type);
1.12 markus 991: break;
992: }
1.83 djm 993: if (key_is_cert(k))
994: key_cert_copy(k, n);
1.12 markus 995: return n;
996: }
997:
998: int
999: key_type_from_name(char *name)
1000: {
1.35 deraadt 1001: if (strcmp(name, "rsa1") == 0) {
1.12 markus 1002: return KEY_RSA1;
1.35 deraadt 1003: } else if (strcmp(name, "rsa") == 0) {
1.12 markus 1004: return KEY_RSA;
1.35 deraadt 1005: } else if (strcmp(name, "dsa") == 0) {
1.12 markus 1006: return KEY_DSA;
1.35 deraadt 1007: } else if (strcmp(name, "ssh-rsa") == 0) {
1.12 markus 1008: return KEY_RSA;
1.35 deraadt 1009: } else if (strcmp(name, "ssh-dss") == 0) {
1.12 markus 1010: return KEY_DSA;
1.83 djm 1011: } else if (strcmp(name, "ssh-rsa-cert-v00@openssh.com") == 0) {
1.87 djm 1012: return KEY_RSA_CERT_V00;
1013: } else if (strcmp(name, "ssh-dss-cert-v00@openssh.com") == 0) {
1014: return KEY_DSA_CERT_V00;
1015: } else if (strcmp(name, "ssh-rsa-cert-v01@openssh.com") == 0) {
1.83 djm 1016: return KEY_RSA_CERT;
1.87 djm 1017: } else if (strcmp(name, "ssh-dss-cert-v01@openssh.com") == 0) {
1.83 djm 1018: return KEY_DSA_CERT;
1.12 markus 1019: }
1.18 markus 1020: debug2("key_type_from_name: unknown key type '%s'", name);
1.12 markus 1021: return KEY_UNSPEC;
1.25 markus 1022: }
1023:
1024: int
1025: key_names_valid2(const char *names)
1026: {
1027: char *s, *cp, *p;
1028:
1029: if (names == NULL || strcmp(names, "") == 0)
1030: return 0;
1031: s = cp = xstrdup(names);
1032: for ((p = strsep(&cp, ",")); p && *p != '\0';
1.36 deraadt 1033: (p = strsep(&cp, ","))) {
1.25 markus 1034: switch (key_type_from_name(p)) {
1035: case KEY_RSA1:
1036: case KEY_UNSPEC:
1037: xfree(s);
1038: return 0;
1039: }
1040: }
1041: debug3("key names ok: [%s]", names);
1042: xfree(s);
1043: return 1;
1.12 markus 1044: }
1045:
1.83 djm 1046: static int
1047: cert_parse(Buffer *b, Key *key, const u_char *blob, u_int blen)
1048: {
1.87 djm 1049: u_char *principals, *critical, *exts, *sig_key, *sig;
1050: u_int signed_len, plen, clen, sklen, slen, kidlen, elen;
1.83 djm 1051: Buffer tmp;
1052: char *principal;
1053: int ret = -1;
1.87 djm 1054: int v00 = key->type == KEY_DSA_CERT_V00 ||
1055: key->type == KEY_RSA_CERT_V00;
1.83 djm 1056:
1057: buffer_init(&tmp);
1058:
1059: /* Copy the entire key blob for verification and later serialisation */
1060: buffer_append(&key->cert->certblob, blob, blen);
1061:
1.87 djm 1062: elen = 0; /* Not touched for v00 certs */
1063: principals = exts = critical = sig_key = sig = NULL;
1064: if ((!v00 && buffer_get_int64_ret(&key->cert->serial, b) != 0) ||
1065: buffer_get_int_ret(&key->cert->type, b) != 0 ||
1.84 djm 1066: (key->cert->key_id = buffer_get_string_ret(b, &kidlen)) == NULL ||
1.83 djm 1067: (principals = buffer_get_string_ret(b, &plen)) == NULL ||
1068: buffer_get_int64_ret(&key->cert->valid_after, b) != 0 ||
1069: buffer_get_int64_ret(&key->cert->valid_before, b) != 0 ||
1.87 djm 1070: (critical = buffer_get_string_ret(b, &clen)) == NULL ||
1071: (!v00 && (exts = buffer_get_string_ret(b, &elen)) == NULL) ||
1072: (v00 && buffer_get_string_ptr_ret(b, NULL) == NULL) || /* nonce */
1073: buffer_get_string_ptr_ret(b, NULL) == NULL || /* reserved */
1.83 djm 1074: (sig_key = buffer_get_string_ret(b, &sklen)) == NULL) {
1075: error("%s: parse error", __func__);
1076: goto out;
1077: }
1078:
1.84 djm 1079: if (kidlen != strlen(key->cert->key_id)) {
1080: error("%s: key ID contains \\0 character", __func__);
1081: goto out;
1082: }
1083:
1.83 djm 1084: /* Signature is left in the buffer so we can calculate this length */
1085: signed_len = buffer_len(&key->cert->certblob) - buffer_len(b);
1086:
1087: if ((sig = buffer_get_string_ret(b, &slen)) == NULL) {
1088: error("%s: parse error", __func__);
1089: goto out;
1090: }
1091:
1092: if (key->cert->type != SSH2_CERT_TYPE_USER &&
1093: key->cert->type != SSH2_CERT_TYPE_HOST) {
1094: error("Unknown certificate type %u", key->cert->type);
1095: goto out;
1096: }
1097:
1098: buffer_append(&tmp, principals, plen);
1099: while (buffer_len(&tmp) > 0) {
1100: if (key->cert->nprincipals >= CERT_MAX_PRINCIPALS) {
1.84 djm 1101: error("%s: Too many principals", __func__);
1.83 djm 1102: goto out;
1103: }
1.84 djm 1104: if ((principal = buffer_get_string_ret(&tmp, &plen)) == NULL) {
1105: error("%s: Principals data invalid", __func__);
1106: goto out;
1107: }
1108: if (strlen(principal) != plen) {
1109: error("%s: Principal contains \\0 character",
1110: __func__);
1.83 djm 1111: goto out;
1112: }
1113: key->cert->principals = xrealloc(key->cert->principals,
1114: key->cert->nprincipals + 1, sizeof(*key->cert->principals));
1115: key->cert->principals[key->cert->nprincipals++] = principal;
1116: }
1117:
1118: buffer_clear(&tmp);
1119:
1.87 djm 1120: buffer_append(&key->cert->critical, critical, clen);
1121: buffer_append(&tmp, critical, clen);
1.83 djm 1122: /* validate structure */
1123: while (buffer_len(&tmp) != 0) {
1.85 djm 1124: if (buffer_get_string_ptr_ret(&tmp, NULL) == NULL ||
1125: buffer_get_string_ptr_ret(&tmp, NULL) == NULL) {
1.87 djm 1126: error("%s: critical option data invalid", __func__);
1127: goto out;
1128: }
1129: }
1130: buffer_clear(&tmp);
1131:
1132: buffer_append(&key->cert->extensions, exts, elen);
1133: buffer_append(&tmp, exts, elen);
1134: /* validate structure */
1135: while (buffer_len(&tmp) != 0) {
1136: if (buffer_get_string_ptr_ret(&tmp, NULL) == NULL ||
1137: buffer_get_string_ptr_ret(&tmp, NULL) == NULL) {
1138: error("%s: extension data invalid", __func__);
1.83 djm 1139: goto out;
1140: }
1141: }
1142: buffer_clear(&tmp);
1143:
1144: if ((key->cert->signature_key = key_from_blob(sig_key,
1145: sklen)) == NULL) {
1.84 djm 1146: error("%s: Signature key invalid", __func__);
1.83 djm 1147: goto out;
1148: }
1149: if (key->cert->signature_key->type != KEY_RSA &&
1150: key->cert->signature_key->type != KEY_DSA) {
1.84 djm 1151: error("%s: Invalid signature key type %s (%d)", __func__,
1.83 djm 1152: key_type(key->cert->signature_key),
1153: key->cert->signature_key->type);
1154: goto out;
1155: }
1156:
1157: switch (key_verify(key->cert->signature_key, sig, slen,
1158: buffer_ptr(&key->cert->certblob), signed_len)) {
1159: case 1:
1.84 djm 1160: ret = 0;
1.83 djm 1161: break; /* Good signature */
1162: case 0:
1.84 djm 1163: error("%s: Invalid signature on certificate", __func__);
1.83 djm 1164: goto out;
1165: case -1:
1.84 djm 1166: error("%s: Certificate signature verification failed",
1167: __func__);
1.83 djm 1168: goto out;
1169: }
1170:
1171: out:
1172: buffer_free(&tmp);
1173: if (principals != NULL)
1174: xfree(principals);
1.87 djm 1175: if (critical != NULL)
1176: xfree(critical);
1177: if (exts != NULL)
1178: xfree(exts);
1.83 djm 1179: if (sig_key != NULL)
1180: xfree(sig_key);
1181: if (sig != NULL)
1182: xfree(sig);
1183: return ret;
1184: }
1185:
1.12 markus 1186: Key *
1.55 jakob 1187: key_from_blob(const u_char *blob, u_int blen)
1.12 markus 1188: {
1189: Buffer b;
1190: int rlen, type;
1.57 djm 1191: char *ktype = NULL;
1.12 markus 1192: Key *key = NULL;
1193:
1194: #ifdef DEBUG_PK
1195: dump_base64(stderr, blob, blen);
1196: #endif
1197: buffer_init(&b);
1198: buffer_append(&b, blob, blen);
1.57 djm 1199: if ((ktype = buffer_get_string_ret(&b, NULL)) == NULL) {
1200: error("key_from_blob: can't read key type");
1201: goto out;
1202: }
1203:
1.12 markus 1204: type = key_type_from_name(ktype);
1205:
1.35 deraadt 1206: switch (type) {
1.87 djm 1207: case KEY_RSA_CERT:
1208: (void)buffer_get_string_ptr_ret(&b, NULL); /* Skip nonce */
1209: /* FALLTHROUGH */
1.12 markus 1210: case KEY_RSA:
1.87 djm 1211: case KEY_RSA_CERT_V00:
1.12 markus 1212: key = key_new(type);
1.57 djm 1213: if (buffer_get_bignum2_ret(&b, key->rsa->e) == -1 ||
1214: buffer_get_bignum2_ret(&b, key->rsa->n) == -1) {
1215: error("key_from_blob: can't read rsa key");
1.83 djm 1216: badkey:
1.57 djm 1217: key_free(key);
1218: key = NULL;
1219: goto out;
1220: }
1.12 markus 1221: #ifdef DEBUG_PK
1222: RSA_print_fp(stderr, key->rsa, 8);
1223: #endif
1224: break;
1.87 djm 1225: case KEY_DSA_CERT:
1226: (void)buffer_get_string_ptr_ret(&b, NULL); /* Skip nonce */
1227: /* FALLTHROUGH */
1.12 markus 1228: case KEY_DSA:
1.87 djm 1229: case KEY_DSA_CERT_V00:
1.12 markus 1230: key = key_new(type);
1.57 djm 1231: if (buffer_get_bignum2_ret(&b, key->dsa->p) == -1 ||
1232: buffer_get_bignum2_ret(&b, key->dsa->q) == -1 ||
1233: buffer_get_bignum2_ret(&b, key->dsa->g) == -1 ||
1234: buffer_get_bignum2_ret(&b, key->dsa->pub_key) == -1) {
1235: error("key_from_blob: can't read dsa key");
1.83 djm 1236: goto badkey;
1.57 djm 1237: }
1.12 markus 1238: #ifdef DEBUG_PK
1239: DSA_print_fp(stderr, key->dsa, 8);
1240: #endif
1241: break;
1242: case KEY_UNSPEC:
1243: key = key_new(type);
1244: break;
1245: default:
1246: error("key_from_blob: cannot handle type %s", ktype);
1.57 djm 1247: goto out;
1.12 markus 1248: }
1.83 djm 1249: if (key_is_cert(key) && cert_parse(&b, key, blob, blen) == -1) {
1250: error("key_from_blob: can't parse cert data");
1251: goto badkey;
1252: }
1.12 markus 1253: rlen = buffer_len(&b);
1254: if (key != NULL && rlen != 0)
1255: error("key_from_blob: remaining bytes in key blob %d", rlen);
1.57 djm 1256: out:
1257: if (ktype != NULL)
1258: xfree(ktype);
1.12 markus 1259: buffer_free(&b);
1260: return key;
1261: }
1262:
1263: int
1.55 jakob 1264: key_to_blob(const Key *key, u_char **blobp, u_int *lenp)
1.12 markus 1265: {
1266: Buffer b;
1267: int len;
1268:
1269: if (key == NULL) {
1270: error("key_to_blob: key == NULL");
1271: return 0;
1272: }
1273: buffer_init(&b);
1.35 deraadt 1274: switch (key->type) {
1.87 djm 1275: case KEY_DSA_CERT_V00:
1276: case KEY_RSA_CERT_V00:
1.83 djm 1277: case KEY_DSA_CERT:
1278: case KEY_RSA_CERT:
1279: /* Use the existing blob */
1280: buffer_append(&b, buffer_ptr(&key->cert->certblob),
1281: buffer_len(&key->cert->certblob));
1282: break;
1.12 markus 1283: case KEY_DSA:
1284: buffer_put_cstring(&b, key_ssh_name(key));
1285: buffer_put_bignum2(&b, key->dsa->p);
1286: buffer_put_bignum2(&b, key->dsa->q);
1287: buffer_put_bignum2(&b, key->dsa->g);
1288: buffer_put_bignum2(&b, key->dsa->pub_key);
1289: break;
1290: case KEY_RSA:
1291: buffer_put_cstring(&b, key_ssh_name(key));
1.14 markus 1292: buffer_put_bignum2(&b, key->rsa->e);
1.12 markus 1293: buffer_put_bignum2(&b, key->rsa->n);
1294: break;
1295: default:
1.31 markus 1296: error("key_to_blob: unsupported key type %d", key->type);
1297: buffer_free(&b);
1298: return 0;
1.12 markus 1299: }
1300: len = buffer_len(&b);
1.48 markus 1301: if (lenp != NULL)
1302: *lenp = len;
1303: if (blobp != NULL) {
1304: *blobp = xmalloc(len);
1305: memcpy(*blobp, buffer_ptr(&b), len);
1306: }
1.12 markus 1307: memset(buffer_ptr(&b), 0, len);
1308: buffer_free(&b);
1309: return len;
1310: }
1311:
1312: int
1313: key_sign(
1.55 jakob 1314: const Key *key,
1.40 markus 1315: u_char **sigp, u_int *lenp,
1.55 jakob 1316: const u_char *data, u_int datalen)
1.12 markus 1317: {
1.35 deraadt 1318: switch (key->type) {
1.87 djm 1319: case KEY_DSA_CERT_V00:
1.83 djm 1320: case KEY_DSA_CERT:
1.12 markus 1321: case KEY_DSA:
1322: return ssh_dss_sign(key, sigp, lenp, data, datalen);
1.87 djm 1323: case KEY_RSA_CERT_V00:
1.83 djm 1324: case KEY_RSA_CERT:
1.12 markus 1325: case KEY_RSA:
1326: return ssh_rsa_sign(key, sigp, lenp, data, datalen);
1327: default:
1.56 markus 1328: error("key_sign: invalid key type %d", key->type);
1.12 markus 1329: return -1;
1330: }
1331: }
1332:
1.44 markus 1333: /*
1334: * key_verify returns 1 for a correct signature, 0 for an incorrect signature
1335: * and -1 on error.
1336: */
1.12 markus 1337: int
1338: key_verify(
1.55 jakob 1339: const Key *key,
1340: const u_char *signature, u_int signaturelen,
1341: const u_char *data, u_int datalen)
1.12 markus 1342: {
1.26 markus 1343: if (signaturelen == 0)
1344: return -1;
1345:
1.35 deraadt 1346: switch (key->type) {
1.87 djm 1347: case KEY_DSA_CERT_V00:
1.83 djm 1348: case KEY_DSA_CERT:
1.12 markus 1349: case KEY_DSA:
1350: return ssh_dss_verify(key, signature, signaturelen, data, datalen);
1.87 djm 1351: case KEY_RSA_CERT_V00:
1.83 djm 1352: case KEY_RSA_CERT:
1.12 markus 1353: case KEY_RSA:
1354: return ssh_rsa_verify(key, signature, signaturelen, data, datalen);
1355: default:
1.56 markus 1356: error("key_verify: invalid key type %d", key->type);
1.12 markus 1357: return -1;
1358: }
1.42 markus 1359: }
1360:
1361: /* Converts a private to a public key */
1362: Key *
1.55 jakob 1363: key_demote(const Key *k)
1.42 markus 1364: {
1365: Key *pk;
1.43 markus 1366:
1.63 djm 1367: pk = xcalloc(1, sizeof(*pk));
1.42 markus 1368: pk->type = k->type;
1369: pk->flags = k->flags;
1370: pk->dsa = NULL;
1371: pk->rsa = NULL;
1372:
1373: switch (k->type) {
1.87 djm 1374: case KEY_RSA_CERT_V00:
1.83 djm 1375: case KEY_RSA_CERT:
1376: key_cert_copy(k, pk);
1377: /* FALLTHROUGH */
1.42 markus 1378: case KEY_RSA1:
1379: case KEY_RSA:
1380: if ((pk->rsa = RSA_new()) == NULL)
1381: fatal("key_demote: RSA_new failed");
1382: if ((pk->rsa->e = BN_dup(k->rsa->e)) == NULL)
1383: fatal("key_demote: BN_dup failed");
1384: if ((pk->rsa->n = BN_dup(k->rsa->n)) == NULL)
1385: fatal("key_demote: BN_dup failed");
1386: break;
1.87 djm 1387: case KEY_DSA_CERT_V00:
1.83 djm 1388: case KEY_DSA_CERT:
1389: key_cert_copy(k, pk);
1390: /* FALLTHROUGH */
1.42 markus 1391: case KEY_DSA:
1392: if ((pk->dsa = DSA_new()) == NULL)
1393: fatal("key_demote: DSA_new failed");
1394: if ((pk->dsa->p = BN_dup(k->dsa->p)) == NULL)
1395: fatal("key_demote: BN_dup failed");
1396: if ((pk->dsa->q = BN_dup(k->dsa->q)) == NULL)
1397: fatal("key_demote: BN_dup failed");
1398: if ((pk->dsa->g = BN_dup(k->dsa->g)) == NULL)
1399: fatal("key_demote: BN_dup failed");
1400: if ((pk->dsa->pub_key = BN_dup(k->dsa->pub_key)) == NULL)
1401: fatal("key_demote: BN_dup failed");
1402: break;
1403: default:
1404: fatal("key_free: bad key type %d", k->type);
1405: break;
1406: }
1407:
1408: return (pk);
1.83 djm 1409: }
1410:
1411: int
1412: key_is_cert(const Key *k)
1413: {
1.87 djm 1414: if (k == NULL)
1415: return 0;
1416: switch (k->type) {
1417: case KEY_RSA_CERT_V00:
1418: case KEY_DSA_CERT_V00:
1419: case KEY_RSA_CERT:
1420: case KEY_DSA_CERT:
1421: return 1;
1422: default:
1423: return 0;
1424: }
1.83 djm 1425: }
1426:
1427: /* Return the cert-less equivalent to a certified key type */
1428: int
1429: key_type_plain(int type)
1430: {
1431: switch (type) {
1.87 djm 1432: case KEY_RSA_CERT_V00:
1.83 djm 1433: case KEY_RSA_CERT:
1434: return KEY_RSA;
1.87 djm 1435: case KEY_DSA_CERT_V00:
1.83 djm 1436: case KEY_DSA_CERT:
1437: return KEY_DSA;
1438: default:
1439: return type;
1440: }
1441: }
1442:
1443: /* Convert a KEY_RSA or KEY_DSA to their _CERT equivalent */
1444: int
1.87 djm 1445: key_to_certified(Key *k, int legacy)
1.83 djm 1446: {
1447: switch (k->type) {
1448: case KEY_RSA:
1449: k->cert = cert_new();
1.87 djm 1450: k->type = legacy ? KEY_RSA_CERT_V00 : KEY_RSA_CERT;
1.83 djm 1451: return 0;
1452: case KEY_DSA:
1453: k->cert = cert_new();
1.87 djm 1454: k->type = legacy ? KEY_DSA_CERT_V00 : KEY_DSA_CERT;
1.83 djm 1455: return 0;
1456: default:
1457: error("%s: key has incorrect type %s", __func__, key_type(k));
1458: return -1;
1459: }
1460: }
1461:
1462: /* Convert a KEY_RSA_CERT or KEY_DSA_CERT to their raw key equivalent */
1463: int
1464: key_drop_cert(Key *k)
1465: {
1466: switch (k->type) {
1.87 djm 1467: case KEY_RSA_CERT_V00:
1.83 djm 1468: case KEY_RSA_CERT:
1469: cert_free(k->cert);
1470: k->type = KEY_RSA;
1471: return 0;
1.87 djm 1472: case KEY_DSA_CERT_V00:
1.83 djm 1473: case KEY_DSA_CERT:
1474: cert_free(k->cert);
1475: k->type = KEY_DSA;
1476: return 0;
1477: default:
1478: error("%s: key has incorrect type %s", __func__, key_type(k));
1479: return -1;
1480: }
1481: }
1482:
1483: /* Sign a KEY_RSA_CERT or KEY_DSA_CERT, (re-)generating the signed certblob */
1484: int
1485: key_certify(Key *k, Key *ca)
1486: {
1487: Buffer principals;
1488: u_char *ca_blob, *sig_blob, nonce[32];
1489: u_int i, ca_len, sig_len;
1490:
1491: if (k->cert == NULL) {
1492: error("%s: key lacks cert info", __func__);
1493: return -1;
1494: }
1495:
1496: if (!key_is_cert(k)) {
1497: error("%s: certificate has unknown type %d", __func__,
1498: k->cert->type);
1499: return -1;
1500: }
1501:
1502: if (ca->type != KEY_RSA && ca->type != KEY_DSA) {
1503: error("%s: CA key has unsupported type %s", __func__,
1504: key_type(ca));
1505: return -1;
1506: }
1507:
1508: key_to_blob(ca, &ca_blob, &ca_len);
1509:
1510: buffer_clear(&k->cert->certblob);
1511: buffer_put_cstring(&k->cert->certblob, key_ssh_name(k));
1512:
1.87 djm 1513: /* -v01 certs put nonce first */
1514: if (k->type == KEY_DSA_CERT || k->type == KEY_RSA_CERT) {
1515: arc4random_buf(&nonce, sizeof(nonce));
1516: buffer_put_string(&k->cert->certblob, nonce, sizeof(nonce));
1517: }
1518:
1.83 djm 1519: switch (k->type) {
1.87 djm 1520: case KEY_DSA_CERT_V00:
1.83 djm 1521: case KEY_DSA_CERT:
1522: buffer_put_bignum2(&k->cert->certblob, k->dsa->p);
1523: buffer_put_bignum2(&k->cert->certblob, k->dsa->q);
1524: buffer_put_bignum2(&k->cert->certblob, k->dsa->g);
1525: buffer_put_bignum2(&k->cert->certblob, k->dsa->pub_key);
1526: break;
1.87 djm 1527: case KEY_RSA_CERT_V00:
1.83 djm 1528: case KEY_RSA_CERT:
1529: buffer_put_bignum2(&k->cert->certblob, k->rsa->e);
1530: buffer_put_bignum2(&k->cert->certblob, k->rsa->n);
1531: break;
1532: default:
1533: error("%s: key has incorrect type %s", __func__, key_type(k));
1534: buffer_clear(&k->cert->certblob);
1535: xfree(ca_blob);
1536: return -1;
1537: }
1538:
1.87 djm 1539: /* -v01 certs have a serial number next */
1540: if (k->type == KEY_DSA_CERT || k->type == KEY_RSA_CERT)
1541: buffer_put_int64(&k->cert->certblob, k->cert->serial);
1542:
1.83 djm 1543: buffer_put_int(&k->cert->certblob, k->cert->type);
1544: buffer_put_cstring(&k->cert->certblob, k->cert->key_id);
1545:
1546: buffer_init(&principals);
1547: for (i = 0; i < k->cert->nprincipals; i++)
1548: buffer_put_cstring(&principals, k->cert->principals[i]);
1549: buffer_put_string(&k->cert->certblob, buffer_ptr(&principals),
1550: buffer_len(&principals));
1551: buffer_free(&principals);
1552:
1553: buffer_put_int64(&k->cert->certblob, k->cert->valid_after);
1554: buffer_put_int64(&k->cert->certblob, k->cert->valid_before);
1555: buffer_put_string(&k->cert->certblob,
1.87 djm 1556: buffer_ptr(&k->cert->critical), buffer_len(&k->cert->critical));
1557:
1558: /* -v01 certs have non-critical options here */
1559: if (k->type == KEY_DSA_CERT || k->type == KEY_RSA_CERT) {
1560: buffer_put_string(&k->cert->certblob,
1561: buffer_ptr(&k->cert->extensions),
1562: buffer_len(&k->cert->extensions));
1563: }
1564:
1565: /* -v00 certs put the nonce at the end */
1566: if (k->type == KEY_DSA_CERT_V00 || k->type == KEY_RSA_CERT_V00)
1567: buffer_put_string(&k->cert->certblob, nonce, sizeof(nonce));
1.83 djm 1568:
1569: buffer_put_string(&k->cert->certblob, NULL, 0); /* reserved */
1570: buffer_put_string(&k->cert->certblob, ca_blob, ca_len);
1571: xfree(ca_blob);
1572:
1573: /* Sign the whole mess */
1574: if (key_sign(ca, &sig_blob, &sig_len, buffer_ptr(&k->cert->certblob),
1575: buffer_len(&k->cert->certblob)) != 0) {
1576: error("%s: signature operation failed", __func__);
1577: buffer_clear(&k->cert->certblob);
1578: return -1;
1579: }
1580: /* Append signature and we are done */
1581: buffer_put_string(&k->cert->certblob, sig_blob, sig_len);
1582: xfree(sig_blob);
1583:
1584: return 0;
1585: }
1586:
1587: int
1588: key_cert_check_authority(const Key *k, int want_host, int require_principal,
1589: const char *name, const char **reason)
1590: {
1591: u_int i, principal_matches;
1592: time_t now = time(NULL);
1593:
1594: if (want_host) {
1595: if (k->cert->type != SSH2_CERT_TYPE_HOST) {
1596: *reason = "Certificate invalid: not a host certificate";
1597: return -1;
1598: }
1599: } else {
1600: if (k->cert->type != SSH2_CERT_TYPE_USER) {
1601: *reason = "Certificate invalid: not a user certificate";
1602: return -1;
1603: }
1604: }
1605: if (now < 0) {
1606: error("%s: system clock lies before epoch", __func__);
1607: *reason = "Certificate invalid: not yet valid";
1608: return -1;
1609: }
1610: if ((u_int64_t)now < k->cert->valid_after) {
1611: *reason = "Certificate invalid: not yet valid";
1612: return -1;
1613: }
1614: if ((u_int64_t)now >= k->cert->valid_before) {
1615: *reason = "Certificate invalid: expired";
1616: return -1;
1617: }
1618: if (k->cert->nprincipals == 0) {
1619: if (require_principal) {
1620: *reason = "Certificate lacks principal list";
1621: return -1;
1622: }
1.88 djm 1623: } else if (name != NULL) {
1.83 djm 1624: principal_matches = 0;
1625: for (i = 0; i < k->cert->nprincipals; i++) {
1626: if (strcmp(name, k->cert->principals[i]) == 0) {
1627: principal_matches = 1;
1628: break;
1629: }
1630: }
1631: if (!principal_matches) {
1632: *reason = "Certificate invalid: name is not a listed "
1633: "principal";
1634: return -1;
1635: }
1636: }
1637: return 0;
1.87 djm 1638: }
1639:
1640: int
1641: key_cert_is_legacy(Key *k)
1642: {
1643: switch (k->type) {
1644: case KEY_DSA_CERT_V00:
1645: case KEY_RSA_CERT_V00:
1646: return 1;
1647: default:
1648: return 0;
1649: }
1.4 markus 1650: }
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