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 1.32 2000/10/09 21:30:44 markus Exp $");
17 #include <openssl/evp.h>
18 #include <openssl/pem.h>
19 #include <openssl/rsa.h>
20 #include <openssl/dsa.h>
33 /* Number of bits in the RSA/DSA key. This value can be changed on the command line. */
37 * Flag indicating that we just want to change the passphrase. This can be
38 * set on the command line.
40 int change_passphrase = 0;
43 * Flag indicating that we just want to change the comment. This can be set
44 * on the command line.
46 int change_comment = 0;
50 /* Flag indicating that we just want to see the key fingerprint */
51 int print_fingerprint = 0;
53 /* The identity file name, given on the command line or entered by the user. */
54 char identity_file[1024];
55 int have_identity = 0;
57 /* This is set to the passphrase if given on the command line. */
58 char *identity_passphrase = NULL;
60 /* This is set to the new passphrase if given on the command line. */
61 char *identity_new_passphrase = NULL;
63 /* This is set to the new comment if given on the command line. */
64 char *identity_comment = NULL;
66 /* Dump public key file in format used by real and the original SSH 2 */
67 int convert_to_ssh2 = 0;
68 int convert_from_ssh2 = 0;
73 #ifdef HAVE___PROGNAME
74 extern char *__progname;
75 #else /* HAVE___PROGNAME */
76 static const char *__progname = "ssh-keygen";
77 #endif /* HAVE___PROGNAME */
79 char hostname[MAXHOSTNAMELEN];
82 ask_filename(struct passwd *pw, const char *prompt)
85 snprintf(identity_file, sizeof(identity_file), "%s/%s",
87 dsa_mode ? SSH_CLIENT_ID_DSA: SSH_CLIENT_IDENTITY);
88 printf("%s (%s): ", prompt, identity_file);
90 if (fgets(buf, sizeof(buf), stdin) == NULL)
92 if (strchr(buf, '\n'))
93 *strchr(buf, '\n') = 0;
94 if (strcmp(buf, "") != 0)
95 strlcpy(identity_file, buf, sizeof(identity_file));
100 try_load_key(char *filename, Key *k)
103 if (!load_private_key(filename, "", k, NULL)) {
104 char *pass = read_passphrase("Enter passphrase: ", 1);
105 if (!load_private_key(filename, pass, k, NULL)) {
108 memset(pass, 0, strlen(pass));
114 #define SSH_COM_PUBLIC_BEGIN "---- BEGIN SSH2 PUBLIC KEY ----"
115 #define SSH_COM_PUBLIC_END "---- END SSH2 PUBLIC KEY ----"
116 #define SSH_COM_PRIVATE_BEGIN "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----"
117 #define SSH_COM_PRIVATE_KEY_MAGIC 0x3f6ff9eb
120 do_convert_to_ssh2(struct passwd *pw)
128 ask_filename(pw, "Enter file in which the key is");
129 if (stat(identity_file, &st) < 0) {
130 perror(identity_file);
133 k = key_new(KEY_DSA);
134 if (!try_load_key(identity_file, k)) {
135 fprintf(stderr, "load failed\n");
138 dsa_make_key_blob(k, &blob, &len);
139 fprintf(stdout, "%s\n", SSH_COM_PUBLIC_BEGIN);
141 "Comment: \"%d-bit %s, converted from OpenSSH by %s@%s\"\n",
142 key_size(k), key_type(k),
143 pw->pw_name, hostname);
144 dump_base64(stdout, blob, len);
145 fprintf(stdout, "%s\n", SSH_COM_PUBLIC_END);
152 buffer_get_bignum_bits(Buffer *b, BIGNUM *value)
154 int bits = buffer_get_int(b);
155 int bytes = (bits + 7) / 8;
156 if (buffer_len(b) < bytes)
157 fatal("buffer_get_bignum_bits: input buffer too small");
158 BN_bin2bn((unsigned char *)buffer_ptr(b), bytes, value);
159 buffer_consume(b, bytes);
163 do_convert_private_ssh2_from_blob(char *blob, int blen)
168 int ignore, magic, rlen;
172 buffer_append(&b, blob, blen);
174 magic = buffer_get_int(&b);
175 if (magic != SSH_COM_PRIVATE_KEY_MAGIC) {
176 error("bad magic 0x%x != 0x%x", magic, SSH_COM_PRIVATE_KEY_MAGIC);
180 ignore = buffer_get_int(&b);
181 type = buffer_get_string(&b, NULL);
182 cipher = buffer_get_string(&b, NULL);
183 ignore = buffer_get_int(&b);
184 ignore = buffer_get_int(&b);
185 ignore = buffer_get_int(&b);
188 if (strcmp(cipher, "none") != 0) {
189 error("unsupported cipher %s", cipher);
196 key = key_new(KEY_DSA);
198 dsa->priv_key = BN_new();
199 if (dsa->priv_key == NULL) {
200 error("alloc priv_key failed");
204 buffer_get_bignum_bits(&b, dsa->p);
205 buffer_get_bignum_bits(&b, dsa->g);
206 buffer_get_bignum_bits(&b, dsa->q);
207 buffer_get_bignum_bits(&b, dsa->pub_key);
208 buffer_get_bignum_bits(&b, dsa->priv_key);
209 rlen = buffer_len(&b);
211 error("do_convert_private_ssh2_from_blob: remaining bytes in key blob %d", rlen);
217 do_convert_from_ssh2(struct passwd *pw)
225 int escaped = 0, private = 0, ok;
229 ask_filename(pw, "Enter file in which the key is");
230 if (stat(identity_file, &st) < 0) {
231 perror(identity_file);
234 fp = fopen(identity_file, "r");
236 perror(identity_file);
240 while (fgets(line, sizeof(line), fp)) {
241 if (!(p = strchr(line, '\n'))) {
242 fprintf(stderr, "input line too long.\n");
245 if (p > line && p[-1] == '\\')
247 if (strncmp(line, "----", 4) == 0 ||
248 strstr(line, ": ") != NULL) {
249 if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
251 fprintf(stderr, "ignore: %s", line);
256 fprintf(stderr, "escaped: %s", line);
260 strlcat(encoded, line, sizeof(encoded));
262 blen = uudecode(encoded, (unsigned char *)blob, sizeof(blob));
264 fprintf(stderr, "uudecode failed.\n");
268 do_convert_private_ssh2_from_blob(blob, blen) :
269 dsa_key_from_blob(blob, blen);
271 fprintf(stderr, "decode blob failed.\n");
275 PEM_write_DSAPrivateKey(stdout, k->dsa, NULL, NULL, 0, NULL, NULL) :
276 key_write(k, stdout);
278 fprintf(stderr, "key write failed");
282 fprintf(stdout, "\n");
288 do_print_public(struct passwd *pw)
296 ask_filename(pw, "Enter file in which the key is");
297 if (stat(identity_file, &st) < 0) {
298 perror(identity_file);
301 k = key_new(KEY_DSA);
302 if (!try_load_key(identity_file, k)) {
303 fprintf(stderr, "load failed\n");
306 dsa_make_key_blob(k, &blob, &len);
307 if (!key_write(k, stdout))
308 fprintf(stderr, "key_write failed");
311 fprintf(stdout, "\n");
316 do_fingerprint(struct passwd *pw)
322 char *comment = NULL, *cp, *ep, line[16*1024];
323 int i, skip = 0, num = 1, invalid = 1;
328 ask_filename(pw, "Enter file in which the key is");
329 if (stat(identity_file, &st) < 0) {
330 perror(identity_file);
333 public = key_new(KEY_RSA);
334 if (load_public_key(identity_file, public, &comment)) {
335 printf("%d %s %s\n", BN_num_bits(public->rsa->n),
336 key_fingerprint(public), comment);
341 f = fopen(identity_file, "r");
343 while (fgets(line, sizeof(line), f)) {
344 i = strlen(line) - 1;
345 if (line[i] != '\n') {
346 error("line %d too long: %.40s...", num, line);
357 /* Skip leading whitespace, empty and comment lines. */
358 for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
360 if (!*cp || *cp == '\n' || *cp == '#')
362 i = strtol(cp, &ep, 10);
363 if (i == 0 || ep == NULL || (*ep != ' ' && *ep != '\t')) {
366 for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
367 if (*cp == '\\' && cp[1] == '"')
368 cp++; /* Skip both */
377 if (auth_rsa_read_key(&cp, &ignore, public->rsa->e, public->rsa->n)) {
379 comment = *cp ? cp : comment;
380 printf("%d %s %s\n", key_size(public),
381 key_fingerprint(public),
382 comment ? comment : "no comment");
389 printf("%s is not a valid key file.\n", identity_file);
396 * Perform changing a passphrase. The argument is the passwd structure
397 * for the current user.
400 do_change_passphrase(struct passwd *pw)
403 char *old_passphrase, *passphrase1, *passphrase2;
407 int type = dsa_mode ? KEY_DSA : KEY_RSA;
410 ask_filename(pw, "Enter file in which the key is");
411 if (stat(identity_file, &st) < 0) {
412 perror(identity_file);
416 if (type == KEY_RSA) {
417 /* XXX this works currently only for RSA */
418 public = key_new(type);
419 if (!load_public_key(identity_file, public, NULL)) {
420 printf("%s is not a valid key file.\n", identity_file);
423 /* Clear the public key since we are just about to load the whole file. */
427 /* Try to load the file with empty passphrase. */
428 private = key_new(type);
429 if (!load_private_key(identity_file, "", private, &comment)) {
430 if (identity_passphrase)
431 old_passphrase = xstrdup(identity_passphrase);
433 old_passphrase = read_passphrase("Enter old passphrase: ", 1);
434 if (!load_private_key(identity_file, old_passphrase, private, &comment)) {
435 memset(old_passphrase, 0, strlen(old_passphrase));
436 xfree(old_passphrase);
437 printf("Bad passphrase.\n");
440 memset(old_passphrase, 0, strlen(old_passphrase));
441 xfree(old_passphrase);
443 printf("Key has comment '%s'\n", comment);
445 /* Ask the new passphrase (twice). */
446 if (identity_new_passphrase) {
447 passphrase1 = xstrdup(identity_new_passphrase);
451 read_passphrase("Enter new passphrase (empty for no passphrase): ", 1);
452 passphrase2 = read_passphrase("Enter same passphrase again: ", 1);
454 /* Verify that they are the same. */
455 if (strcmp(passphrase1, passphrase2) != 0) {
456 memset(passphrase1, 0, strlen(passphrase1));
457 memset(passphrase2, 0, strlen(passphrase2));
460 printf("Pass phrases do not match. Try again.\n");
463 /* Destroy the other copy. */
464 memset(passphrase2, 0, strlen(passphrase2));
468 /* Save the file using the new passphrase. */
469 if (!save_private_key(identity_file, passphrase1, private, comment)) {
470 printf("Saving the key failed: %s: %s.\n",
471 identity_file, strerror(errno));
472 memset(passphrase1, 0, strlen(passphrase1));
478 /* Destroy the passphrase and the copy of the key in memory. */
479 memset(passphrase1, 0, strlen(passphrase1));
481 key_free(private); /* Destroys contents */
484 printf("Your identification has been saved with the new passphrase.\n");
489 * Change the comment of a private key file.
492 do_change_comment(struct passwd *pw)
494 char new_comment[1024], *comment;
502 ask_filename(pw, "Enter file in which the key is");
503 if (stat(identity_file, &st) < 0) {
504 perror(identity_file);
508 * Try to load the public key from the file the verify that it is
509 * readable and of the proper format.
511 public = key_new(KEY_RSA);
512 if (!load_public_key(identity_file, public, NULL)) {
513 printf("%s is not a valid key file.\n", identity_file);
517 private = key_new(KEY_RSA);
518 if (load_private_key(identity_file, "", private, &comment))
519 passphrase = xstrdup("");
521 if (identity_passphrase)
522 passphrase = xstrdup(identity_passphrase);
523 else if (identity_new_passphrase)
524 passphrase = xstrdup(identity_new_passphrase);
526 passphrase = read_passphrase("Enter passphrase: ", 1);
527 /* Try to load using the passphrase. */
528 if (!load_private_key(identity_file, passphrase, private, &comment)) {
529 memset(passphrase, 0, strlen(passphrase));
531 printf("Bad passphrase.\n");
535 printf("Key now has comment '%s'\n", comment);
537 if (identity_comment) {
538 strlcpy(new_comment, identity_comment, sizeof(new_comment));
540 printf("Enter new comment: ");
542 if (!fgets(new_comment, sizeof(new_comment), stdin)) {
543 memset(passphrase, 0, strlen(passphrase));
547 if (strchr(new_comment, '\n'))
548 *strchr(new_comment, '\n') = 0;
551 /* Save the file using the new passphrase. */
552 if (!save_private_key(identity_file, passphrase, private, new_comment)) {
553 printf("Saving the key failed: %s: %s.\n",
554 identity_file, strerror(errno));
555 memset(passphrase, 0, strlen(passphrase));
561 memset(passphrase, 0, strlen(passphrase));
565 strlcat(identity_file, ".pub", sizeof(identity_file));
566 f = fopen(identity_file, "w");
568 printf("Could not save your public key in %s\n", identity_file);
571 if (!key_write(public, f))
572 fprintf(stderr, "write key failed");
574 fprintf(f, " %s\n", new_comment);
579 printf("The comment in your key file has been changed.\n");
586 printf("Usage: %s [-lpqxXydc] [-b bits] [-f file] [-C comment] [-N new-pass] [-P pass]\n", __progname);
591 * Main program for key management.
594 main(int ac, char **av)
596 char dotsshdir[16 * 1024], comment[1024], *passphrase1, *passphrase2;
608 SSLeay_add_all_algorithms();
610 /* we need this for the home * directory. */
611 pw = getpwuid(getuid());
613 printf("You don't exist, go away!\n");
616 if (gethostname(hostname, sizeof(hostname)) < 0) {
617 perror("gethostname");
621 while ((opt = getopt(ac, av, "dqpclRxXyb:f:P:N:C:")) != EOF) {
625 if (bits < 512 || bits > 32768) {
626 printf("Bits has bad value.\n");
632 print_fingerprint = 1;
636 change_passphrase = 1;
644 strlcpy(identity_file, optarg, sizeof(identity_file));
649 identity_passphrase = optarg;
653 identity_new_passphrase = optarg;
657 identity_comment = optarg;
665 if (rsa_alive() == 0)
676 convert_from_ssh2 = 1;
693 printf("Too many arguments.\n");
696 if (change_passphrase && change_comment) {
697 printf("Can only have one of -p and -c.\n");
700 /* check if RSA support is needed and exists */
701 if (dsa_mode == 0 && rsa_alive() == 0) {
703 "%s: no RSA support in libssl and libcrypto. See ssl(8).\n",
707 if (print_fingerprint)
709 if (change_passphrase)
710 do_change_passphrase(pw);
712 do_change_comment(pw);
714 do_convert_to_ssh2(pw);
715 if (convert_from_ssh2)
716 do_convert_from_ssh2(pw);
724 printf("Generating DSA parameter and key.\n");
725 public = private = dsa_generate_key(bits);
726 if (private == NULL) {
727 fprintf(stderr, "dsa_generate_keys failed");
733 /* Generate the rsa key pair. */
734 public = key_new(KEY_RSA);
735 private = key_new(KEY_RSA);
736 rsa_generate_key(private->rsa, public->rsa, bits);
740 ask_filename(pw, "Enter file in which to save the key");
742 /* Create ~/.ssh directory if it doesn\'t already exist. */
743 snprintf(dotsshdir, sizeof dotsshdir, "%s/%s", pw->pw_dir, SSH_USER_DIR);
744 if (strstr(identity_file, dotsshdir) != NULL &&
745 stat(dotsshdir, &st) < 0) {
746 if (mkdir(dotsshdir, 0700) < 0)
747 error("Could not create directory '%s'.", dotsshdir);
749 printf("Created directory '%s'.\n", dotsshdir);
751 /* If the file already exists, ask the user to confirm. */
752 if (stat(identity_file, &st) >= 0) {
754 printf("%s already exists.\n", identity_file);
755 printf("Overwrite (y/n)? ");
757 if (fgets(yesno, sizeof(yesno), stdin) == NULL)
759 if (yesno[0] != 'y' && yesno[0] != 'Y')
762 /* Ask for a passphrase (twice). */
763 if (identity_passphrase)
764 passphrase1 = xstrdup(identity_passphrase);
765 else if (identity_new_passphrase)
766 passphrase1 = xstrdup(identity_new_passphrase);
770 read_passphrase("Enter passphrase (empty for no passphrase): ", 1);
771 passphrase2 = read_passphrase("Enter same passphrase again: ", 1);
772 if (strcmp(passphrase1, passphrase2) != 0) {
773 /* The passphrases do not match. Clear them and retry. */
774 memset(passphrase1, 0, strlen(passphrase1));
775 memset(passphrase2, 0, strlen(passphrase2));
778 printf("Passphrases do not match. Try again.\n");
779 goto passphrase_again;
781 /* Clear the other copy of the passphrase. */
782 memset(passphrase2, 0, strlen(passphrase2));
786 if (identity_comment) {
787 strlcpy(comment, identity_comment, sizeof(comment));
789 /* Create default commend field for the passphrase. */
790 snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
793 /* Save the key with the given passphrase and comment. */
794 if (!save_private_key(identity_file, passphrase1, private, comment)) {
795 printf("Saving the key failed: %s: %s.\n",
796 identity_file, strerror(errno));
797 memset(passphrase1, 0, strlen(passphrase1));
801 /* Clear the passphrase. */
802 memset(passphrase1, 0, strlen(passphrase1));
805 /* Clear the private key and the random number generator. */
806 if (private != public) {
812 printf("Your identification has been saved in %s.\n", identity_file);
814 strlcat(identity_file, ".pub", sizeof(identity_file));
815 f = fopen(identity_file, "w");
817 printf("Could not save your public key in %s\n", identity_file);
820 if (!key_write(public, f))
821 fprintf(stderr, "write key failed");
822 fprintf(f, " %s\n", comment);
826 printf("Your public key has been saved in %s.\n",
828 printf("The key fingerprint is:\n");
829 printf("%s %s\n", key_fingerprint(public), comment);