2 * Author: Tatu Ylonen <ylo@cs.hut.fi>
3 * Copyright (c) 1994 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5 * Identity and host key generation and maintenance.
7 * As far as I am concerned, the code I have written for this software
8 * can be used freely for any purpose. Any derived versions of this
9 * software must be clearly marked as such, and if the derived work is
10 * incompatible with the protocol description in the RFC file, it must be
11 * called by a name other than "ssh" or "Secure Shell".
15 RCSID("$OpenBSD: ssh-keygen.c,v 1.37 2000/12/22 16:49:40 markus Exp $");
17 #include <openssl/evp.h>
18 #include <openssl/pem.h>
19 #include <openssl/rsa.h>
20 #include <openssl/dsa.h>
32 /* Number of bits in the RSA/DSA key. This value can be changed on the command line. */
36 * Flag indicating that we just want to change the passphrase. This can be
37 * set on the command line.
39 int change_passphrase = 0;
42 * Flag indicating that we just want to change the comment. This can be set
43 * on the command line.
45 int change_comment = 0;
49 /* Flag indicating that we just want to see the key fingerprint */
50 int print_fingerprint = 0;
52 /* The identity file name, given on the command line or entered by the user. */
53 char identity_file[1024];
54 int have_identity = 0;
56 /* This is set to the passphrase if given on the command line. */
57 char *identity_passphrase = NULL;
59 /* This is set to the new passphrase if given on the command line. */
60 char *identity_new_passphrase = NULL;
62 /* This is set to the new comment if given on the command line. */
63 char *identity_comment = NULL;
65 /* Dump public key file in format used by real and the original SSH 2 */
66 int convert_to_ssh2 = 0;
67 int convert_from_ssh2 = 0;
70 /* default to RSA for SSH-1 */
71 char *key_type_name = "rsa1";
74 #ifdef HAVE___PROGNAME
75 extern char *__progname;
80 char hostname[MAXHOSTNAMELEN];
83 ask_filename(struct passwd *pw, const char *prompt)
88 switch (key_type_from_name(key_type_name)) {
90 name = SSH_CLIENT_IDENTITY;
93 name = SSH_CLIENT_ID_DSA;
96 name = SSH_CLIENT_ID_RSA;
99 fprintf(stderr, "bad key type");
103 snprintf(identity_file, sizeof(identity_file), "%s/%s", pw->pw_dir, name);
104 fprintf(stderr, "%s (%s): ", prompt, identity_file);
106 if (fgets(buf, sizeof(buf), stdin) == NULL)
108 if (strchr(buf, '\n'))
109 *strchr(buf, '\n') = 0;
110 if (strcmp(buf, "") != 0)
111 strlcpy(identity_file, buf, sizeof(identity_file));
116 try_load_key(char *filename, Key *k)
119 if (!load_private_key(filename, "", k, NULL)) {
120 char *pass = read_passphrase("Enter passphrase: ", 1);
121 if (!load_private_key(filename, pass, k, NULL)) {
124 memset(pass, 0, strlen(pass));
130 #define SSH_COM_PUBLIC_BEGIN "---- BEGIN SSH2 PUBLIC KEY ----"
131 #define SSH_COM_PUBLIC_END "---- END SSH2 PUBLIC KEY ----"
132 #define SSH_COM_PRIVATE_BEGIN "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----"
133 #define SSH_COM_PRIVATE_KEY_MAGIC 0x3f6ff9eb
136 do_convert_to_ssh2(struct passwd *pw)
144 ask_filename(pw, "Enter file in which the key is");
145 if (stat(identity_file, &st) < 0) {
146 perror(identity_file);
149 k = key_new(KEY_UNSPEC);
150 if (!try_load_key(identity_file, k)) {
151 fprintf(stderr, "load failed\n");
154 key_to_blob(k, &blob, &len);
155 fprintf(stdout, "%s\n", SSH_COM_PUBLIC_BEGIN);
157 "Comment: \"%d-bit %s, converted from OpenSSH by %s@%s\"\n",
158 key_size(k), key_type(k),
159 pw->pw_name, hostname);
160 dump_base64(stdout, blob, len);
161 fprintf(stdout, "%s\n", SSH_COM_PUBLIC_END);
168 buffer_get_bignum_bits(Buffer *b, BIGNUM *value)
170 int bits = buffer_get_int(b);
171 int bytes = (bits + 7) / 8;
172 if (buffer_len(b) < bytes)
173 fatal("buffer_get_bignum_bits: input buffer too small");
174 BN_bin2bn((u_char *)buffer_ptr(b), bytes, value);
175 buffer_consume(b, bytes);
179 do_convert_private_ssh2_from_blob(char *blob, int blen)
184 int ignore, magic, rlen;
188 buffer_append(&b, blob, blen);
190 magic = buffer_get_int(&b);
191 if (magic != SSH_COM_PRIVATE_KEY_MAGIC) {
192 error("bad magic 0x%x != 0x%x", magic, SSH_COM_PRIVATE_KEY_MAGIC);
196 ignore = buffer_get_int(&b);
197 type = buffer_get_string(&b, NULL);
198 cipher = buffer_get_string(&b, NULL);
199 ignore = buffer_get_int(&b);
200 ignore = buffer_get_int(&b);
201 ignore = buffer_get_int(&b);
204 if (strcmp(cipher, "none") != 0) {
205 error("unsupported cipher %s", cipher);
212 key = key_new(KEY_DSA);
214 dsa->priv_key = BN_new();
215 if (dsa->priv_key == NULL) {
216 error("alloc priv_key failed");
220 buffer_get_bignum_bits(&b, dsa->p);
221 buffer_get_bignum_bits(&b, dsa->g);
222 buffer_get_bignum_bits(&b, dsa->q);
223 buffer_get_bignum_bits(&b, dsa->pub_key);
224 buffer_get_bignum_bits(&b, dsa->priv_key);
225 rlen = buffer_len(&b);
227 error("do_convert_private_ssh2_from_blob: remaining bytes in key blob %d", rlen);
233 do_convert_from_ssh2(struct passwd *pw)
241 int escaped = 0, private = 0, ok;
245 ask_filename(pw, "Enter file in which the key is");
246 if (stat(identity_file, &st) < 0) {
247 perror(identity_file);
250 fp = fopen(identity_file, "r");
252 perror(identity_file);
256 while (fgets(line, sizeof(line), fp)) {
257 if (!(p = strchr(line, '\n'))) {
258 fprintf(stderr, "input line too long.\n");
261 if (p > line && p[-1] == '\\')
263 if (strncmp(line, "----", 4) == 0 ||
264 strstr(line, ": ") != NULL) {
265 if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
267 fprintf(stderr, "ignore: %s", line);
272 fprintf(stderr, "escaped: %s", line);
276 strlcat(encoded, line, sizeof(encoded));
278 blen = uudecode(encoded, (u_char *)blob, sizeof(blob));
280 fprintf(stderr, "uudecode failed.\n");
284 do_convert_private_ssh2_from_blob(blob, blen) :
285 key_from_blob(blob, blen);
287 fprintf(stderr, "decode blob failed.\n");
291 PEM_write_DSAPrivateKey(stdout, k->dsa, NULL, NULL, 0, NULL, NULL) :
292 key_write(k, stdout);
294 fprintf(stderr, "key write failed");
298 fprintf(stdout, "\n");
304 do_print_public(struct passwd *pw)
310 ask_filename(pw, "Enter file in which the key is");
311 if (stat(identity_file, &st) < 0) {
312 perror(identity_file);
315 k = key_new(KEY_UNSPEC);
316 if (!try_load_key(identity_file, k)) {
317 fprintf(stderr, "load failed\n");
320 if (!key_write(k, stdout))
321 fprintf(stderr, "key_write failed");
323 fprintf(stdout, "\n");
328 do_fingerprint(struct passwd *pw)
333 char *comment = NULL, *cp, *ep, line[16*1024];
334 int i, skip = 0, num = 1, invalid = 1, success = 0;
339 ask_filename(pw, "Enter file in which the key is");
340 if (stat(identity_file, &st) < 0) {
341 perror(identity_file);
344 public = key_new(KEY_RSA1);
345 if (load_public_key(identity_file, public, &comment)) {
349 public = key_new(KEY_UNSPEC);
350 if (try_load_public_key(identity_file, public, &comment))
353 error("try_load_public_key KEY_UNSPEC failed");
356 printf("%d %s %s\n", key_size(public), key_fingerprint(public), comment);
364 public = key_new(KEY_RSA1);
365 f = fopen(identity_file, "r");
367 while (fgets(line, sizeof(line), f)) {
368 i = strlen(line) - 1;
369 if (line[i] != '\n') {
370 error("line %d too long: %.40s...", num, line);
381 /* Skip leading whitespace, empty and comment lines. */
382 for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
384 if (!*cp || *cp == '\n' || *cp == '#')
386 i = strtol(cp, &ep, 10);
387 if (i == 0 || ep == NULL || (*ep != ' ' && *ep != '\t')) {
390 for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
391 if (*cp == '\\' && cp[1] == '"')
392 cp++; /* Skip both */
401 if (auth_rsa_read_key(&cp, &ignore, public->rsa->e, public->rsa->n)) {
403 comment = *cp ? cp : comment;
404 printf("%d %s %s\n", key_size(public),
405 key_fingerprint(public),
406 comment ? comment : "no comment");
413 printf("%s is not a valid key file.\n", identity_file);
420 * Perform changing a passphrase. The argument is the passwd structure
421 * for the current user.
424 do_change_passphrase(struct passwd *pw)
427 char *old_passphrase, *passphrase1, *passphrase2;
434 ask_filename(pw, "Enter file in which the key is");
435 if (stat(identity_file, &st) < 0) {
436 perror(identity_file);
439 public = key_new(type);
440 if (!load_public_key(identity_file, public, NULL)) {
443 /* Clear the public key since we are just about to load the whole file. */
446 /* Try to load the file with empty passphrase. */
447 private = key_new(type);
448 if (!load_private_key(identity_file, "", private, &comment)) {
449 if (identity_passphrase)
450 old_passphrase = xstrdup(identity_passphrase);
452 old_passphrase = read_passphrase("Enter old passphrase: ", 1);
453 if (!load_private_key(identity_file, old_passphrase, private, &comment)) {
454 memset(old_passphrase, 0, strlen(old_passphrase));
455 xfree(old_passphrase);
456 printf("Bad passphrase.\n");
459 memset(old_passphrase, 0, strlen(old_passphrase));
460 xfree(old_passphrase);
462 printf("Key has comment '%s'\n", comment);
464 /* Ask the new passphrase (twice). */
465 if (identity_new_passphrase) {
466 passphrase1 = xstrdup(identity_new_passphrase);
470 read_passphrase("Enter new passphrase (empty for no passphrase): ", 1);
471 passphrase2 = read_passphrase("Enter same passphrase again: ", 1);
473 /* Verify that they are the same. */
474 if (strcmp(passphrase1, passphrase2) != 0) {
475 memset(passphrase1, 0, strlen(passphrase1));
476 memset(passphrase2, 0, strlen(passphrase2));
479 printf("Pass phrases do not match. Try again.\n");
482 /* Destroy the other copy. */
483 memset(passphrase2, 0, strlen(passphrase2));
487 /* Save the file using the new passphrase. */
488 if (!save_private_key(identity_file, passphrase1, private, comment)) {
489 printf("Saving the key failed: %s: %s.\n",
490 identity_file, strerror(errno));
491 memset(passphrase1, 0, strlen(passphrase1));
497 /* Destroy the passphrase and the copy of the key in memory. */
498 memset(passphrase1, 0, strlen(passphrase1));
500 key_free(private); /* Destroys contents */
503 printf("Your identification has been saved with the new passphrase.\n");
508 * Change the comment of a private key file.
511 do_change_comment(struct passwd *pw)
513 char new_comment[1024], *comment;
521 ask_filename(pw, "Enter file in which the key is");
522 if (stat(identity_file, &st) < 0) {
523 perror(identity_file);
527 * Try to load the public key from the file the verify that it is
528 * readable and of the proper format.
530 public = key_new(KEY_RSA1);
531 if (!load_public_key(identity_file, public, NULL)) {
532 printf("%s is not a valid key file.\n", identity_file);
536 private = key_new(KEY_RSA1);
537 if (load_private_key(identity_file, "", private, &comment))
538 passphrase = xstrdup("");
540 if (identity_passphrase)
541 passphrase = xstrdup(identity_passphrase);
542 else if (identity_new_passphrase)
543 passphrase = xstrdup(identity_new_passphrase);
545 passphrase = read_passphrase("Enter passphrase: ", 1);
546 /* Try to load using the passphrase. */
547 if (!load_private_key(identity_file, passphrase, private, &comment)) {
548 memset(passphrase, 0, strlen(passphrase));
550 printf("Bad passphrase.\n");
554 printf("Key now has comment '%s'\n", comment);
556 if (identity_comment) {
557 strlcpy(new_comment, identity_comment, sizeof(new_comment));
559 printf("Enter new comment: ");
561 if (!fgets(new_comment, sizeof(new_comment), stdin)) {
562 memset(passphrase, 0, strlen(passphrase));
566 if (strchr(new_comment, '\n'))
567 *strchr(new_comment, '\n') = 0;
570 /* Save the file using the new passphrase. */
571 if (!save_private_key(identity_file, passphrase, private, new_comment)) {
572 printf("Saving the key failed: %s: %s.\n",
573 identity_file, strerror(errno));
574 memset(passphrase, 0, strlen(passphrase));
580 memset(passphrase, 0, strlen(passphrase));
584 strlcat(identity_file, ".pub", sizeof(identity_file));
585 f = fopen(identity_file, "w");
587 printf("Could not save your public key in %s\n", identity_file);
590 if (!key_write(public, f))
591 fprintf(stderr, "write key failed");
593 fprintf(f, " %s\n", new_comment);
598 printf("The comment in your key file has been changed.\n");
605 printf("Usage: %s [-lpqxXyc] [-t type] [-b bits] [-f file] [-C comment] [-N new-pass] [-P pass]\n", __progname);
610 * Main program for key management.
613 main(int ac, char **av)
615 char dotsshdir[16 * 1024], comment[1024], *passphrase1, *passphrase2;
626 __progname = get_progname(av[0]);
629 SSLeay_add_all_algorithms();
631 /* we need this for the home * directory. */
632 pw = getpwuid(getuid());
634 printf("You don't exist, go away!\n");
637 if (gethostname(hostname, sizeof(hostname)) < 0) {
638 perror("gethostname");
642 while ((opt = getopt(ac, av, "dqpclRxXyb:f:t:P:N:C:")) != EOF) {
646 if (bits < 512 || bits > 32768) {
647 printf("Bits has bad value.\n");
653 print_fingerprint = 1;
657 change_passphrase = 1;
665 strlcpy(identity_file, optarg, sizeof(identity_file));
670 identity_passphrase = optarg;
674 identity_new_passphrase = optarg;
678 identity_comment = optarg;
695 convert_from_ssh2 = 1;
703 key_type_name = "dsa";
707 key_type_name = optarg;
716 printf("Too many arguments.\n");
719 if (change_passphrase && change_comment) {
720 printf("Can only have one of -p and -c.\n");
723 if (print_fingerprint)
725 if (change_passphrase)
726 do_change_passphrase(pw);
728 do_change_comment(pw);
730 do_convert_to_ssh2(pw);
731 if (convert_from_ssh2)
732 do_convert_from_ssh2(pw);
738 type = key_type_from_name(key_type_name);
739 if (type == KEY_UNSPEC) {
740 fprintf(stderr, "unknown key type %s\n", key_type_name);
744 printf("Generating public/private %s key pair.\n", key_type_name);
745 private = key_generate(type, bits);
746 if (private == NULL) {
747 fprintf(stderr, "key_generate failed");
750 public = key_from_private(private);
753 ask_filename(pw, "Enter file in which to save the key");
755 /* Create ~/.ssh directory if it doesn\'t already exist. */
756 snprintf(dotsshdir, sizeof dotsshdir, "%s/%s", pw->pw_dir, SSH_USER_DIR);
757 if (strstr(identity_file, dotsshdir) != NULL &&
758 stat(dotsshdir, &st) < 0) {
759 if (mkdir(dotsshdir, 0700) < 0)
760 error("Could not create directory '%s'.", dotsshdir);
762 printf("Created directory '%s'.\n", dotsshdir);
764 /* If the file already exists, ask the user to confirm. */
765 if (stat(identity_file, &st) >= 0) {
767 printf("%s already exists.\n", identity_file);
768 printf("Overwrite (y/n)? ");
770 if (fgets(yesno, sizeof(yesno), stdin) == NULL)
772 if (yesno[0] != 'y' && yesno[0] != 'Y')
775 /* Ask for a passphrase (twice). */
776 if (identity_passphrase)
777 passphrase1 = xstrdup(identity_passphrase);
778 else if (identity_new_passphrase)
779 passphrase1 = xstrdup(identity_new_passphrase);
783 read_passphrase("Enter passphrase (empty for no passphrase): ", 1);
784 passphrase2 = read_passphrase("Enter same passphrase again: ", 1);
785 if (strcmp(passphrase1, passphrase2) != 0) {
786 /* The passphrases do not match. Clear them and retry. */
787 memset(passphrase1, 0, strlen(passphrase1));
788 memset(passphrase2, 0, strlen(passphrase2));
791 printf("Passphrases do not match. Try again.\n");
792 goto passphrase_again;
794 /* Clear the other copy of the passphrase. */
795 memset(passphrase2, 0, strlen(passphrase2));
799 if (identity_comment) {
800 strlcpy(comment, identity_comment, sizeof(comment));
802 /* Create default commend field for the passphrase. */
803 snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
806 /* Save the key with the given passphrase and comment. */
807 if (!save_private_key(identity_file, passphrase1, private, comment)) {
808 printf("Saving the key failed: %s: %s.\n",
809 identity_file, strerror(errno));
810 memset(passphrase1, 0, strlen(passphrase1));
814 /* Clear the passphrase. */
815 memset(passphrase1, 0, strlen(passphrase1));
818 /* Clear the private key and the random number generator. */
823 printf("Your identification has been saved in %s.\n", identity_file);
825 strlcat(identity_file, ".pub", sizeof(identity_file));
826 f = fopen(identity_file, "w");
828 printf("Could not save your public key in %s\n", identity_file);
831 if (!key_write(public, f))
832 fprintf(stderr, "write key failed");
833 fprintf(f, " %s\n", comment);
837 printf("Your public key has been saved in %s.\n",
839 printf("The key fingerprint is:\n");
840 printf("%s %s\n", key_fingerprint(public), comment);