Annotation of src/usr.bin/ssh/authfile.c, Revision 1.93
1.93 ! markus 1: /* $OpenBSD: authfile.c,v 1.92 2011/06/14 22:49:18 markus Exp $ */
1.1 deraadt 2: /*
1.9 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * This file contains functions for reading and writing identity files, and
7: * for reading the passphrase from the user.
1.14 markus 8: *
1.19 deraadt 9: * As far as I am concerned, the code I have written for this software
10: * can be used freely for any purpose. Any derived versions of this
11: * software must be clearly marked as such, and if the derived work is
12: * incompatible with the protocol description in the RFC file, it must be
13: * called by a name other than "ssh" or "Secure Shell".
14: *
15: *
16: * Copyright (c) 2000 Markus Friedl. All rights reserved.
17: *
18: * Redistribution and use in source and binary forms, with or without
19: * modification, are permitted provided that the following conditions
20: * are met:
21: * 1. Redistributions of source code must retain the above copyright
22: * notice, this list of conditions and the following disclaimer.
23: * 2. Redistributions in binary form must reproduce the above copyright
24: * notice, this list of conditions and the following disclaimer in the
25: * documentation and/or other materials provided with the distribution.
26: *
27: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
28: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
29: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
30: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
31: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
32: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
33: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
34: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
35: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
36: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.9 deraadt 37: */
1.1 deraadt 38:
1.62 stevesk 39:
40: #include <sys/types.h>
41: #include <sys/stat.h>
1.72 stevesk 42: #include <sys/param.h>
1.76 deraadt 43: #include <sys/uio.h>
1.1 deraadt 44:
1.21 markus 45: #include <openssl/err.h>
1.25 markus 46: #include <openssl/evp.h>
1.15 markus 47: #include <openssl/pem.h>
1.68 stevesk 48:
1.69 stevesk 49: #include <errno.h>
1.68 stevesk 50: #include <fcntl.h>
1.74 stevesk 51: #include <stdio.h>
1.73 stevesk 52: #include <stdlib.h>
1.71 stevesk 53: #include <string.h>
1.70 stevesk 54: #include <unistd.h>
1.15 markus 55:
1.76 deraadt 56: #include "xmalloc.h"
1.25 markus 57: #include "cipher.h"
1.1 deraadt 58: #include "buffer.h"
1.25 markus 59: #include "key.h"
1.1 deraadt 60: #include "ssh.h"
1.25 markus 61: #include "log.h"
1.27 itojun 62: #include "authfile.h"
1.44 markus 63: #include "rsa.h"
1.60 dtucker 64: #include "misc.h"
1.61 djm 65: #include "atomicio.h"
1.1 deraadt 66:
1.88 djm 67: #define MAX_KEY_FILE_SIZE (1024 * 1024)
68:
1.29 markus 69: /* Version identification string for SSH v1 identity files. */
1.26 stevesk 70: static const char authfile_id_string[] =
71: "SSH PRIVATE KEY FILE FORMAT 1.1\n";
1.1 deraadt 72:
1.10 markus 73: /*
1.86 djm 74: * Serialises the authentication (private) key to a blob, encrypting it with
75: * passphrase. The identification of the blob (lowest 64 bits of n) will
1.10 markus 76: * precede the key to provide identification of the key without needing a
77: * passphrase.
78: */
1.37 itojun 79: static int
1.86 djm 80: key_private_rsa1_to_blob(Key *key, Buffer *blob, const char *passphrase,
1.29 markus 81: const char *comment)
1.1 deraadt 82: {
1.8 markus 83: Buffer buffer, encrypted;
1.45 stevesk 84: u_char buf[100], *cp;
1.86 djm 85: int i, cipher_num;
1.20 markus 86: CipherContext ciphercontext;
87: Cipher *cipher;
1.57 avsm 88: u_int32_t rnd;
1.8 markus 89:
1.10 markus 90: /*
91: * If the passphrase is empty, use SSH_CIPHER_NONE to ease converting
92: * to another cipher; otherwise use SSH_AUTHFILE_CIPHER.
93: */
1.46 markus 94: cipher_num = (strcmp(passphrase, "") == 0) ?
95: SSH_CIPHER_NONE : SSH_AUTHFILE_CIPHER;
96: if ((cipher = cipher_by_number(cipher_num)) == NULL)
1.20 markus 97: fatal("save_private_key_rsa: bad cipher");
1.8 markus 98:
99: /* This buffer is used to built the secret part of the private key. */
100: buffer_init(&buffer);
101:
102: /* Put checkbytes for checking passphrase validity. */
1.57 avsm 103: rnd = arc4random();
104: buf[0] = rnd & 0xff;
105: buf[1] = (rnd >> 8) & 0xff;
1.8 markus 106: buf[2] = buf[0];
107: buf[3] = buf[1];
108: buffer_append(&buffer, buf, 4);
109:
1.10 markus 110: /*
111: * Store the private key (n and e will not be stored because they
112: * will be stored in plain text, and storing them also in encrypted
113: * format would just give known plaintext).
114: */
1.29 markus 115: buffer_put_bignum(&buffer, key->rsa->d);
116: buffer_put_bignum(&buffer, key->rsa->iqmp);
117: buffer_put_bignum(&buffer, key->rsa->q); /* reverse from SSL p */
118: buffer_put_bignum(&buffer, key->rsa->p); /* reverse from SSL q */
1.8 markus 119:
120: /* Pad the part to be encrypted until its size is a multiple of 8. */
121: while (buffer_len(&buffer) % 8 != 0)
122: buffer_put_char(&buffer, 0);
123:
124: /* This buffer will be used to contain the data in the file. */
125: buffer_init(&encrypted);
126:
127: /* First store keyfile id string. */
1.26 stevesk 128: for (i = 0; authfile_id_string[i]; i++)
129: buffer_put_char(&encrypted, authfile_id_string[i]);
1.8 markus 130: buffer_put_char(&encrypted, 0);
131:
132: /* Store cipher type. */
1.46 markus 133: buffer_put_char(&encrypted, cipher_num);
1.8 markus 134: buffer_put_int(&encrypted, 0); /* For future extension */
135:
136: /* Store public key. This will be in plain text. */
1.29 markus 137: buffer_put_int(&encrypted, BN_num_bits(key->rsa->n));
138: buffer_put_bignum(&encrypted, key->rsa->n);
139: buffer_put_bignum(&encrypted, key->rsa->e);
1.36 markus 140: buffer_put_cstring(&encrypted, comment);
1.8 markus 141:
142: /* Allocate space for the private part of the key in the buffer. */
1.42 stevesk 143: cp = buffer_append_space(&encrypted, buffer_len(&buffer));
1.8 markus 144:
1.46 markus 145: cipher_set_key_string(&ciphercontext, cipher, passphrase,
146: CIPHER_ENCRYPT);
147: cipher_crypt(&ciphercontext, cp,
1.45 stevesk 148: buffer_ptr(&buffer), buffer_len(&buffer));
1.46 markus 149: cipher_cleanup(&ciphercontext);
1.20 markus 150: memset(&ciphercontext, 0, sizeof(ciphercontext));
1.8 markus 151:
152: /* Destroy temporary data. */
153: memset(buf, 0, sizeof(buf));
154: buffer_free(&buffer);
155:
1.86 djm 156: buffer_append(blob, buffer_ptr(&encrypted), buffer_len(&encrypted));
1.8 markus 157: buffer_free(&encrypted);
1.86 djm 158:
1.8 markus 159: return 1;
1.1 deraadt 160: }
161:
1.86 djm 162: /* convert SSH v2 key in OpenSSL PEM format */
1.37 itojun 163: static int
1.86 djm 164: key_private_pem_to_blob(Key *key, Buffer *blob, const char *_passphrase,
1.29 markus 165: const char *comment)
1.15 markus 166: {
1.21 markus 167: int success = 0;
1.86 djm 168: int blen, len = strlen(_passphrase);
1.47 markus 169: u_char *passphrase = (len > 0) ? (u_char *)_passphrase : NULL;
1.77 djm 170: const EVP_CIPHER *cipher = (len > 0) ? EVP_aes_128_cbc() : NULL;
1.86 djm 171: const u_char *bptr;
172: BIO *bio;
1.15 markus 173:
174: if (len > 0 && len <= 4) {
1.31 markus 175: error("passphrase too short: have %d bytes, need > 4", len);
1.15 markus 176: return 0;
177: }
1.86 djm 178: if ((bio = BIO_new(BIO_s_mem())) == NULL) {
179: error("%s: BIO_new failed", __func__);
1.15 markus 180: return 0;
181: }
1.21 markus 182: switch (key->type) {
1.30 markus 183: case KEY_DSA:
1.86 djm 184: success = PEM_write_bio_DSAPrivateKey(bio, key->dsa,
1.30 markus 185: cipher, passphrase, len, NULL, NULL);
186: break;
1.83 djm 187: case KEY_ECDSA:
1.86 djm 188: success = PEM_write_bio_ECPrivateKey(bio, key->ecdsa,
1.83 djm 189: cipher, passphrase, len, NULL, NULL);
190: break;
1.30 markus 191: case KEY_RSA:
1.86 djm 192: success = PEM_write_bio_RSAPrivateKey(bio, key->rsa,
1.30 markus 193: cipher, passphrase, len, NULL, NULL);
194: break;
1.15 markus 195: }
1.86 djm 196: if (success) {
197: if ((blen = BIO_get_mem_data(bio, &bptr)) <= 0)
198: success = 0;
199: else
200: buffer_append(blob, bptr, blen);
201: }
202: BIO_free(bio);
1.15 markus 203: return success;
204: }
205:
1.86 djm 206: /* Save a key blob to a file */
207: static int
208: key_save_private_blob(Buffer *keybuf, const char *filename)
209: {
210: int fd;
211:
212: if ((fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600)) < 0) {
213: error("open %s failed: %s.", filename, strerror(errno));
214: return 0;
215: }
216: if (atomicio(vwrite, fd, buffer_ptr(keybuf),
217: buffer_len(keybuf)) != buffer_len(keybuf)) {
218: error("write to key file %s failed: %s", filename,
219: strerror(errno));
220: close(fd);
221: unlink(filename);
222: return 0;
223: }
224: close(fd);
225: return 1;
226: }
227:
228: /* Serialise "key" to buffer "blob" */
229: static int
230: key_private_to_blob(Key *key, Buffer *blob, const char *passphrase,
1.15 markus 231: const char *comment)
232: {
233: switch (key->type) {
1.21 markus 234: case KEY_RSA1:
1.86 djm 235: return key_private_rsa1_to_blob(key, blob, passphrase, comment);
1.15 markus 236: case KEY_DSA:
1.83 djm 237: case KEY_ECDSA:
1.21 markus 238: case KEY_RSA:
1.86 djm 239: return key_private_pem_to_blob(key, blob, passphrase, comment);
1.15 markus 240: default:
1.86 djm 241: error("%s: cannot save key type %d", __func__, key->type);
242: return 0;
1.15 markus 243: }
1.86 djm 244: }
245:
246: int
247: key_save_private(Key *key, const char *filename, const char *passphrase,
248: const char *comment)
249: {
250: Buffer keyblob;
251: int success = 0;
252:
253: buffer_init(&keyblob);
254: if (!key_private_to_blob(key, &keyblob, passphrase, comment))
255: goto out;
256: if (!key_save_private_blob(&keyblob, filename))
257: goto out;
258: success = 1;
259: out:
260: buffer_free(&keyblob);
261: return success;
1.15 markus 262: }
263:
1.10 markus 264: /*
1.86 djm 265: * Parse the public, unencrypted portion of a RSA1 key.
1.10 markus 266: */
1.37 itojun 267: static Key *
1.86 djm 268: key_parse_public_rsa1(Buffer *blob, char **commentp)
1.1 deraadt 269: {
1.29 markus 270: Key *pub;
1.92 markus 271: Buffer copy;
1.86 djm 272:
273: /* Check that it is at least big enough to contain the ID string. */
274: if (buffer_len(blob) < sizeof(authfile_id_string)) {
275: debug3("Truncated RSA1 identifier");
276: return NULL;
277: }
278:
279: /*
280: * Make sure it begins with the id string. Consume the id string
281: * from the buffer.
282: */
283: if (memcmp(buffer_ptr(blob), authfile_id_string,
284: sizeof(authfile_id_string)) != 0) {
285: debug3("Incorrect RSA1 identifier");
286: return NULL;
287: }
1.92 markus 288: buffer_init(©);
289: buffer_append(©, buffer_ptr(blob), buffer_len(blob));
290: buffer_consume(©, sizeof(authfile_id_string));
1.86 djm 291:
292: /* Skip cipher type and reserved data. */
1.92 markus 293: (void) buffer_get_char(©); /* cipher type */
294: (void) buffer_get_int(©); /* reserved */
1.86 djm 295:
296: /* Read the public key from the buffer. */
1.92 markus 297: (void) buffer_get_int(©);
1.86 djm 298: pub = key_new(KEY_RSA1);
1.92 markus 299: buffer_get_bignum(©, pub->rsa->n);
300: buffer_get_bignum(©, pub->rsa->e);
1.86 djm 301: if (commentp)
1.92 markus 302: *commentp = buffer_get_string(©, NULL);
1.86 djm 303: /* The encrypted private part is not parsed by this function. */
1.92 markus 304: buffer_free(©);
1.86 djm 305:
306: return pub;
307: }
308:
1.88 djm 309: /* Load a key from a fd into a buffer */
310: int
1.86 djm 311: key_load_file(int fd, const char *filename, Buffer *blob)
312: {
1.88 djm 313: u_char buf[1024];
1.86 djm 314: size_t len;
1.51 fgsch 315: struct stat st;
1.8 markus 316:
1.51 fgsch 317: if (fstat(fd, &st) < 0) {
1.86 djm 318: error("%s: fstat of key file %.200s%sfailed: %.100s", __func__,
319: filename == NULL ? "" : filename,
320: filename == NULL ? "" : " ",
321: strerror(errno));
322: return 0;
1.51 fgsch 323: }
1.88 djm 324: if ((st.st_mode & (S_IFSOCK|S_IFCHR|S_IFIFO)) == 0 &&
325: st.st_size > MAX_KEY_FILE_SIZE) {
326: toobig:
1.86 djm 327: error("%s: key file %.200s%stoo large", __func__,
328: filename == NULL ? "" : filename,
329: filename == NULL ? "" : " ");
330: return 0;
1.58 djm 331: }
1.93 ! markus 332: buffer_clear(blob);
1.88 djm 333: for (;;) {
334: if ((len = atomicio(read, fd, buf, sizeof(buf))) == 0) {
335: if (errno == EPIPE)
336: break;
337: debug("%s: read from key file %.200s%sfailed: %.100s",
338: __func__, filename == NULL ? "" : filename,
339: filename == NULL ? "" : " ", strerror(errno));
340: buffer_clear(blob);
341: bzero(buf, sizeof(buf));
342: return 0;
343: }
344: buffer_append(blob, buf, len);
345: if (buffer_len(blob) > MAX_KEY_FILE_SIZE) {
346: buffer_clear(blob);
347: bzero(buf, sizeof(buf));
348: goto toobig;
349: }
350: }
351: bzero(buf, sizeof(buf));
352: if ((st.st_mode & (S_IFSOCK|S_IFCHR|S_IFIFO)) == 0 &&
353: st.st_size != buffer_len(blob)) {
354: debug("%s: key file %.200s%schanged size while reading",
355: __func__, filename == NULL ? "" : filename,
356: filename == NULL ? "" : " ");
1.86 djm 357: buffer_clear(blob);
358: return 0;
1.8 markus 359: }
1.88 djm 360:
1.86 djm 361: return 1;
362: }
1.8 markus 363:
1.86 djm 364: /*
365: * Loads the public part of the ssh v1 key file. Returns NULL if an error was
366: * encountered (the file does not exist or is not readable), and the key
367: * otherwise.
368: */
369: static Key *
370: key_load_public_rsa1(int fd, const char *filename, char **commentp)
371: {
372: Buffer buffer;
373: Key *pub;
374:
375: buffer_init(&buffer);
376: if (!key_load_file(fd, filename, &buffer)) {
1.8 markus 377: buffer_free(&buffer);
1.29 markus 378: return NULL;
1.8 markus 379: }
380:
1.86 djm 381: pub = key_parse_public_rsa1(&buffer, commentp);
382: if (pub == NULL)
383: debug3("Could not load \"%s\" as a RSA1 public key", filename);
1.1 deraadt 384: buffer_free(&buffer);
1.29 markus 385: return pub;
1.1 deraadt 386: }
387:
1.29 markus 388: /* load public key from private-key file, works only for SSH v1 */
389: Key *
390: key_load_public_type(int type, const char *filename, char **commentp)
1.15 markus 391: {
1.29 markus 392: Key *pub;
393: int fd;
394:
395: if (type == KEY_RSA1) {
396: fd = open(filename, O_RDONLY);
397: if (fd < 0)
398: return NULL;
399: pub = key_load_public_rsa1(fd, filename, commentp);
400: close(fd);
401: return pub;
1.15 markus 402: }
1.29 markus 403: return NULL;
1.15 markus 404: }
405:
1.37 itojun 406: static Key *
1.86 djm 407: key_parse_private_rsa1(Buffer *blob, const char *passphrase, char **commentp)
1.1 deraadt 408: {
1.61 djm 409: int check1, check2, cipher_type;
1.86 djm 410: Buffer decrypted;
1.45 stevesk 411: u_char *cp;
1.20 markus 412: CipherContext ciphercontext;
413: Cipher *cipher;
1.29 markus 414: Key *prv = NULL;
1.92 markus 415: Buffer copy;
1.8 markus 416:
1.86 djm 417: /* Check that it is at least big enough to contain the ID string. */
418: if (buffer_len(blob) < sizeof(authfile_id_string)) {
419: debug3("Truncated RSA1 identifier");
1.51 fgsch 420: return NULL;
421: }
1.8 markus 422:
1.10 markus 423: /*
424: * Make sure it begins with the id string. Consume the id string
425: * from the buffer.
426: */
1.86 djm 427: if (memcmp(buffer_ptr(blob), authfile_id_string,
428: sizeof(authfile_id_string)) != 0) {
429: debug3("Incorrect RSA1 identifier");
430: return NULL;
431: }
1.92 markus 432: buffer_init(©);
433: buffer_append(©, buffer_ptr(blob), buffer_len(blob));
434: buffer_consume(©, sizeof(authfile_id_string));
1.28 deraadt 435:
1.8 markus 436: /* Read cipher type. */
1.92 markus 437: cipher_type = buffer_get_char(©);
438: (void) buffer_get_int(©); /* Reserved data. */
1.8 markus 439:
440: /* Read the public key from the buffer. */
1.92 markus 441: (void) buffer_get_int(©);
1.29 markus 442: prv = key_new_private(KEY_RSA1);
443:
1.92 markus 444: buffer_get_bignum(©, prv->rsa->n);
445: buffer_get_bignum(©, prv->rsa->e);
1.29 markus 446: if (commentp)
1.92 markus 447: *commentp = buffer_get_string(©, NULL);
1.8 markus 448: else
1.92 markus 449: (void)buffer_get_string_ptr(©, NULL);
1.8 markus 450:
451: /* Check that it is a supported cipher. */
1.20 markus 452: cipher = cipher_by_number(cipher_type);
453: if (cipher == NULL) {
1.86 djm 454: debug("Unsupported RSA1 cipher %d", cipher_type);
1.92 markus 455: buffer_free(©);
1.8 markus 456: goto fail;
457: }
458: /* Initialize space for decrypted data. */
459: buffer_init(&decrypted);
1.92 markus 460: cp = buffer_append_space(&decrypted, buffer_len(©));
1.8 markus 461:
462: /* Rest of the buffer is encrypted. Decrypt it using the passphrase. */
1.46 markus 463: cipher_set_key_string(&ciphercontext, cipher, passphrase,
464: CIPHER_DECRYPT);
465: cipher_crypt(&ciphercontext, cp,
1.92 markus 466: buffer_ptr(©), buffer_len(©));
1.46 markus 467: cipher_cleanup(&ciphercontext);
1.20 markus 468: memset(&ciphercontext, 0, sizeof(ciphercontext));
1.92 markus 469: buffer_free(©);
1.1 deraadt 470:
1.8 markus 471: check1 = buffer_get_char(&decrypted);
472: check2 = buffer_get_char(&decrypted);
473: if (check1 != buffer_get_char(&decrypted) ||
474: check2 != buffer_get_char(&decrypted)) {
475: if (strcmp(passphrase, "") != 0)
1.86 djm 476: debug("Bad passphrase supplied for RSA1 key");
1.8 markus 477: /* Bad passphrase. */
478: buffer_free(&decrypted);
1.29 markus 479: goto fail;
1.8 markus 480: }
481: /* Read the rest of the private key. */
1.29 markus 482: buffer_get_bignum(&decrypted, prv->rsa->d);
483: buffer_get_bignum(&decrypted, prv->rsa->iqmp); /* u */
484: /* in SSL and SSH v1 p and q are exchanged */
485: buffer_get_bignum(&decrypted, prv->rsa->q); /* p */
486: buffer_get_bignum(&decrypted, prv->rsa->p); /* q */
1.8 markus 487:
1.29 markus 488: /* calculate p-1 and q-1 */
1.43 markus 489: rsa_generate_additional_parameters(prv->rsa);
1.8 markus 490:
491: buffer_free(&decrypted);
1.52 markus 492:
493: /* enable blinding */
494: if (RSA_blinding_on(prv->rsa, NULL) != 1) {
1.86 djm 495: error("%s: RSA_blinding_on failed", __func__);
1.52 markus 496: goto fail;
497: }
1.29 markus 498: return prv;
499:
500: fail:
501: if (commentp)
502: xfree(*commentp);
503: key_free(prv);
504: return NULL;
1.15 markus 505: }
506:
1.86 djm 507: static Key *
508: key_parse_private_pem(Buffer *blob, int type, const char *passphrase,
1.29 markus 509: char **commentp)
1.15 markus 510: {
1.21 markus 511: EVP_PKEY *pk = NULL;
1.29 markus 512: Key *prv = NULL;
1.21 markus 513: char *name = "<no key>";
1.86 djm 514: BIO *bio;
1.15 markus 515:
1.86 djm 516: if ((bio = BIO_new_mem_buf(buffer_ptr(blob),
517: buffer_len(blob))) == NULL) {
518: error("%s: BIO_new_mem_buf failed", __func__);
1.29 markus 519: return NULL;
1.15 markus 520: }
1.86 djm 521:
522: pk = PEM_read_bio_PrivateKey(bio, NULL, NULL, (char *)passphrase);
523: BIO_free(bio);
1.21 markus 524: if (pk == NULL) {
1.86 djm 525: debug("%s: PEM_read_PrivateKey failed", __func__);
1.21 markus 526: (void)ERR_get_error();
1.29 markus 527: } else if (pk->type == EVP_PKEY_RSA &&
1.41 deraadt 528: (type == KEY_UNSPEC||type==KEY_RSA)) {
1.29 markus 529: prv = key_new(KEY_UNSPEC);
530: prv->rsa = EVP_PKEY_get1_RSA(pk);
531: prv->type = KEY_RSA;
532: name = "rsa w/o comment";
1.21 markus 533: #ifdef DEBUG_PK
1.29 markus 534: RSA_print_fp(stderr, prv->rsa, 8);
1.21 markus 535: #endif
1.52 markus 536: if (RSA_blinding_on(prv->rsa, NULL) != 1) {
1.86 djm 537: error("%s: RSA_blinding_on failed", __func__);
1.52 markus 538: key_free(prv);
539: prv = NULL;
540: }
1.29 markus 541: } else if (pk->type == EVP_PKEY_DSA &&
1.41 deraadt 542: (type == KEY_UNSPEC||type==KEY_DSA)) {
1.29 markus 543: prv = key_new(KEY_UNSPEC);
544: prv->dsa = EVP_PKEY_get1_DSA(pk);
545: prv->type = KEY_DSA;
546: name = "dsa w/o comment";
1.21 markus 547: #ifdef DEBUG_PK
1.29 markus 548: DSA_print_fp(stderr, prv->dsa, 8);
1.21 markus 549: #endif
1.83 djm 550: } else if (pk->type == EVP_PKEY_EC &&
551: (type == KEY_UNSPEC||type==KEY_ECDSA)) {
552: prv = key_new(KEY_UNSPEC);
553: prv->ecdsa = EVP_PKEY_get1_EC_KEY(pk);
554: prv->type = KEY_ECDSA;
1.85 djm 555: if ((prv->ecdsa_nid = key_ecdsa_key_to_nid(prv->ecdsa)) == -1 ||
556: key_curve_nid_to_name(prv->ecdsa_nid) == NULL ||
557: key_ec_validate_public(EC_KEY_get0_group(prv->ecdsa),
1.83 djm 558: EC_KEY_get0_public_key(prv->ecdsa)) != 0 ||
559: key_ec_validate_private(prv->ecdsa) != 0) {
560: error("%s: bad ECDSA key", __func__);
561: key_free(prv);
562: prv = NULL;
563: }
1.84 djm 564: name = "ecdsa w/o comment";
1.83 djm 565: #ifdef DEBUG_PK
1.85 djm 566: if (prv != NULL && prv->ecdsa != NULL)
1.83 djm 567: key_dump_ec_key(prv->ecdsa);
568: #endif
1.15 markus 569: } else {
1.86 djm 570: error("%s: PEM_read_PrivateKey: mismatch or "
571: "unknown EVP_PKEY save_type %d", __func__, pk->save_type);
1.15 markus 572: }
1.21 markus 573: if (pk != NULL)
574: EVP_PKEY_free(pk);
1.29 markus 575: if (prv != NULL && commentp)
576: *commentp = xstrdup(name);
577: debug("read PEM private key done: type %s",
578: prv ? key_type(prv) : "<unknown>");
579: return prv;
1.15 markus 580: }
581:
1.86 djm 582: Key *
583: key_load_private_pem(int fd, int type, const char *passphrase,
584: char **commentp)
585: {
586: Buffer buffer;
587: Key *prv;
588:
589: buffer_init(&buffer);
590: if (!key_load_file(fd, NULL, &buffer)) {
591: buffer_free(&buffer);
592: return NULL;
593: }
594: prv = key_parse_private_pem(&buffer, type, passphrase, commentp);
595: buffer_free(&buffer);
596: return prv;
597: }
598:
1.63 dtucker 599: int
1.29 markus 600: key_perm_ok(int fd, const char *filename)
1.15 markus 601: {
602: struct stat st;
603:
1.38 markus 604: if (fstat(fd, &st) < 0)
605: return 0;
606: /*
607: * if a key owned by the user is accessed, then we check the
608: * permissions of the file. if the key owned by a different user,
609: * then we don't care.
610: */
611: if ((st.st_uid == getuid()) && (st.st_mode & 077) != 0) {
1.15 markus 612: error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
613: error("@ WARNING: UNPROTECTED PRIVATE KEY FILE! @");
614: error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
1.38 markus 615: error("Permissions 0%3.3o for '%s' are too open.",
1.54 djm 616: (u_int)st.st_mode & 0777, filename);
1.15 markus 617: error("It is recommended that your private key files are NOT accessible by others.");
1.29 markus 618: error("This private key will be ignored.");
1.15 markus 619: return 0;
620: }
1.29 markus 621: return 1;
622: }
623:
1.86 djm 624: static Key *
625: key_parse_private_type(Buffer *blob, int type, const char *passphrase,
626: char **commentp)
627: {
628: switch (type) {
629: case KEY_RSA1:
630: return key_parse_private_rsa1(blob, passphrase, commentp);
631: case KEY_DSA:
632: case KEY_ECDSA:
633: case KEY_RSA:
634: case KEY_UNSPEC:
635: return key_parse_private_pem(blob, type, passphrase, commentp);
636: default:
1.90 djm 637: error("%s: cannot parse key type %d", __func__, type);
1.86 djm 638: break;
639: }
640: return NULL;
641: }
642:
1.29 markus 643: Key *
644: key_load_private_type(int type, const char *filename, const char *passphrase,
1.67 dtucker 645: char **commentp, int *perm_ok)
1.29 markus 646: {
647: int fd;
1.86 djm 648: Key *ret;
649: Buffer buffer;
1.29 markus 650:
651: fd = open(filename, O_RDONLY);
1.78 dtucker 652: if (fd < 0) {
653: debug("could not open key file '%s': %s", filename,
654: strerror(errno));
655: if (perm_ok != NULL)
656: *perm_ok = 0;
1.79 dtucker 657: return NULL;
1.78 dtucker 658: }
1.29 markus 659: if (!key_perm_ok(fd, filename)) {
1.67 dtucker 660: if (perm_ok != NULL)
661: *perm_ok = 0;
1.31 markus 662: error("bad permissions: ignore key: %s", filename);
1.29 markus 663: close(fd);
664: return NULL;
665: }
1.67 dtucker 666: if (perm_ok != NULL)
667: *perm_ok = 1;
1.86 djm 668:
669: buffer_init(&buffer);
670: if (!key_load_file(fd, filename, &buffer)) {
671: buffer_free(&buffer);
1.28 deraadt 672: close(fd);
1.86 djm 673: return NULL;
1.15 markus 674: }
1.86 djm 675: close(fd);
676: ret = key_parse_private_type(&buffer, type, passphrase, commentp);
677: buffer_free(&buffer);
678: return ret;
1.29 markus 679: }
680:
681: Key *
1.88 djm 682: key_parse_private(Buffer *buffer, const char *filename,
683: const char *passphrase, char **commentp)
684: {
685: Key *pub, *prv;
686:
687: /* it's a SSH v1 key if the public key part is readable */
1.92 markus 688: pub = key_parse_public_rsa1(buffer, commentp);
1.88 djm 689: if (pub == NULL) {
690: prv = key_parse_private_type(buffer, KEY_UNSPEC,
691: passphrase, NULL);
692: /* use the filename as a comment for PEM */
693: if (commentp && prv)
694: *commentp = xstrdup(filename);
695: } else {
696: key_free(pub);
697: /* key_parse_public_rsa1() has already loaded the comment */
698: prv = key_parse_private_type(buffer, KEY_RSA1, passphrase,
699: NULL);
700: }
701: return prv;
702: }
703:
704: Key *
1.29 markus 705: key_load_private(const char *filename, const char *passphrase,
706: char **commentp)
707: {
1.88 djm 708: Key *prv;
709: Buffer buffer;
1.29 markus 710: int fd;
711:
712: fd = open(filename, O_RDONLY);
1.78 dtucker 713: if (fd < 0) {
714: debug("could not open key file '%s': %s", filename,
715: strerror(errno));
1.29 markus 716: return NULL;
1.78 dtucker 717: }
1.29 markus 718: if (!key_perm_ok(fd, filename)) {
1.31 markus 719: error("bad permissions: ignore key: %s", filename);
1.29 markus 720: close(fd);
721: return NULL;
722: }
1.86 djm 723:
724: buffer_init(&buffer);
725: if (!key_load_file(fd, filename, &buffer)) {
726: buffer_free(&buffer);
727: close(fd);
728: return NULL;
729: }
730: close(fd);
731:
1.88 djm 732: prv = key_parse_private(&buffer, filename, passphrase, commentp);
1.86 djm 733: buffer_free(&buffer);
1.34 markus 734: return prv;
1.18 markus 735: }
736:
1.37 itojun 737: static int
1.29 markus 738: key_try_load_public(Key *k, const char *filename, char **commentp)
1.18 markus 739: {
740: FILE *f;
1.59 dtucker 741: char line[SSH_MAX_PUBKEY_BYTES];
1.18 markus 742: char *cp;
1.60 dtucker 743: u_long linenum = 0;
1.18 markus 744:
745: f = fopen(filename, "r");
746: if (f != NULL) {
1.59 dtucker 747: while (read_keyfile_line(f, filename, line, sizeof(line),
748: &linenum) != -1) {
1.18 markus 749: cp = line;
1.40 deraadt 750: switch (*cp) {
1.18 markus 751: case '#':
752: case '\n':
753: case '\0':
754: continue;
755: }
1.89 djm 756: /* Abort loading if this looks like a private key */
757: if (strncmp(cp, "-----BEGIN", 10) == 0)
758: break;
1.18 markus 759: /* Skip leading whitespace. */
760: for (; *cp && (*cp == ' ' || *cp == '\t'); cp++)
761: ;
762: if (*cp) {
1.21 markus 763: if (key_read(k, &cp) == 1) {
1.91 djm 764: cp[strcspn(cp, "\r\n")] = '\0';
765: if (commentp) {
766: *commentp = xstrdup(*cp ?
767: cp : filename);
768: }
1.18 markus 769: fclose(f);
770: return 1;
771: }
772: }
773: }
774: fclose(f);
775: }
776: return 0;
777: }
778:
1.29 markus 779: /* load public key from ssh v1 private or any pubkey file */
780: Key *
781: key_load_public(const char *filename, char **commentp)
1.18 markus 782: {
1.29 markus 783: Key *pub;
784: char file[MAXPATHLEN];
1.18 markus 785:
1.53 markus 786: /* try rsa1 private key */
1.29 markus 787: pub = key_load_public_type(KEY_RSA1, filename, commentp);
788: if (pub != NULL)
789: return pub;
1.53 markus 790:
791: /* try rsa1 public key */
792: pub = key_new(KEY_RSA1);
793: if (key_try_load_public(pub, filename, commentp) == 1)
794: return pub;
795: key_free(pub);
796:
797: /* try ssh2 public key */
1.29 markus 798: pub = key_new(KEY_UNSPEC);
799: if (key_try_load_public(pub, filename, commentp) == 1)
800: return pub;
801: if ((strlcpy(file, filename, sizeof file) < sizeof(file)) &&
802: (strlcat(file, ".pub", sizeof file) < sizeof(file)) &&
803: (key_try_load_public(pub, file, commentp) == 1))
804: return pub;
1.81 djm 805: key_free(pub);
806: return NULL;
807: }
808:
809: /* Load the certificate associated with the named private key */
810: Key *
811: key_load_cert(const char *filename)
812: {
813: Key *pub;
1.82 djm 814: char *file;
1.81 djm 815:
816: pub = key_new(KEY_UNSPEC);
1.82 djm 817: xasprintf(&file, "%s-cert.pub", filename);
818: if (key_try_load_public(pub, file, NULL) == 1) {
819: xfree(file);
1.81 djm 820: return pub;
1.82 djm 821: }
822: xfree(file);
1.81 djm 823: key_free(pub);
824: return NULL;
825: }
826:
827: /* Load private key and certificate */
828: Key *
829: key_load_private_cert(int type, const char *filename, const char *passphrase,
830: int *perm_ok)
831: {
832: Key *key, *pub;
833:
834: switch (type) {
835: case KEY_RSA:
836: case KEY_DSA:
1.83 djm 837: case KEY_ECDSA:
1.81 djm 838: break;
839: default:
840: error("%s: unsupported key type", __func__);
841: return NULL;
842: }
843:
844: if ((key = key_load_private_type(type, filename,
845: passphrase, NULL, perm_ok)) == NULL)
846: return NULL;
847:
848: if ((pub = key_load_cert(filename)) == NULL) {
849: key_free(key);
850: return NULL;
851: }
852:
853: /* Make sure the private key matches the certificate */
854: if (key_equal_public(key, pub) == 0) {
855: error("%s: certificate does not match private key %s",
856: __func__, filename);
857: } else if (key_to_certified(key, key_cert_is_legacy(pub)) != 0) {
858: error("%s: key_to_certified failed", __func__);
859: } else {
860: key_cert_copy(pub, key);
861: key_free(pub);
862: return key;
863: }
864:
865: key_free(key);
1.29 markus 866: key_free(pub);
867: return NULL;
1.1 deraadt 868: }
1.80 djm 869:
870: /*
871: * Returns 1 if the specified "key" is listed in the file "filename",
872: * 0 if the key is not listed or -1 on error.
873: * If strict_type is set then the key type must match exactly,
874: * otherwise a comparison that ignores certficiate data is performed.
875: */
876: int
877: key_in_file(Key *key, const char *filename, int strict_type)
878: {
879: FILE *f;
880: char line[SSH_MAX_PUBKEY_BYTES];
881: char *cp;
882: u_long linenum = 0;
883: int ret = 0;
884: Key *pub;
885: int (*key_compare)(const Key *, const Key *) = strict_type ?
886: key_equal : key_equal_public;
887:
888: if ((f = fopen(filename, "r")) == NULL) {
889: if (errno == ENOENT) {
890: debug("%s: keyfile \"%s\" missing", __func__, filename);
891: return 0;
892: } else {
893: error("%s: could not open keyfile \"%s\": %s", __func__,
894: filename, strerror(errno));
895: return -1;
896: }
897: }
898:
899: while (read_keyfile_line(f, filename, line, sizeof(line),
900: &linenum) != -1) {
901: cp = line;
902:
903: /* Skip leading whitespace. */
904: for (; *cp && (*cp == ' ' || *cp == '\t'); cp++)
905: ;
906:
907: /* Skip comments and empty lines */
908: switch (*cp) {
909: case '#':
910: case '\n':
911: case '\0':
912: continue;
913: }
914:
915: pub = key_new(KEY_UNSPEC);
916: if (key_read(pub, &cp) != 1) {
917: key_free(pub);
918: continue;
919: }
920: if (key_compare(key, pub)) {
921: ret = 1;
922: key_free(pub);
923: break;
924: }
925: key_free(pub);
926: }
927: fclose(f);
928: return ret;
929: }
930:
![[BACK]](/icons/back.gif){kind=icon}
Return to authfile.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh