| /* |
| |
| ssh-keygen.c |
| |
| Author: Tatu Ylonen <ylo@cs.hut.fi> |
| |
| Copyright (c) 1994 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
| All rights reserved |
| |
| Created: Mon Mar 27 02:26:40 1995 ylo |
| |
| Identity and host key generation and maintenance. |
| |
| */ |
| |
| #include "includes.h" |
| RCSID("$Id: ssh-keygen.c,v 1.6 1999/11/20 06:02:56 damien Exp $"); |
| |
| #include "rsa.h" |
| #include "ssh.h" |
| #include "xmalloc.h" |
| #include "fingerprint.h" |
| |
| #ifdef HAVE___PROGNAME |
| extern char *__progname; |
| #else /* HAVE___PROGNAME */ |
| const char *__progname = "ssh-keygen"; |
| #endif /* HAVE___PROGNAME */ |
| |
| /* Generated private key. */ |
| RSA *private_key; |
| |
| /* Generated public key. */ |
| RSA *public_key; |
| |
| /* Number of bits in the RSA key. This value can be changed on the command |
| line. */ |
| int bits = 1024; |
| |
| /* Flag indicating that we just want to change the passphrase. This can be |
| set on the command line. */ |
| int change_passphrase = 0; |
| |
| /* Flag indicating that we just want to change the comment. This can be set |
| on the command line. */ |
| int change_comment = 0; |
| |
| int quiet = 0; |
| |
| /* Flag indicating that we just want to see the key fingerprint */ |
| int print_fingerprint = 0; |
| |
| /* This is set to the identity file name if given on the command line. */ |
| char *identity_file = NULL; |
| |
| /* This is set to the passphrase if given on the command line. */ |
| char *identity_passphrase = NULL; |
| |
| /* This is set to the new passphrase if given on the command line. */ |
| char *identity_new_passphrase = NULL; |
| |
| /* This is set to the new comment if given on the command line. */ |
| char *identity_comment = NULL; |
| |
| /* Perform changing a passphrase. The argument is the passwd structure |
| for the current user. */ |
| |
| char * |
| get_filename(struct passwd *pw, const char *prompt) |
| { |
| char buf[1024], default_file[1024]; |
| |
| /* Read key file name. */ |
| if (identity_file != NULL) { |
| return xstrdup(identity_file); |
| } else { |
| snprintf(default_file, sizeof default_file, "%s/%s", |
| pw->pw_dir, SSH_CLIENT_IDENTITY); |
| printf("%s (%s): ", prompt, default_file); |
| fflush(stdout); |
| if (fgets(buf, sizeof(buf), stdin) == NULL) |
| exit(1); |
| if (strchr(buf, '\n')) |
| *strchr(buf, '\n') = 0; |
| if (strcmp(buf, "") == 0) |
| return xstrdup(default_file); |
| } |
| return xstrdup(buf); |
| } |
| |
| void |
| do_fingerprint(struct passwd *pw) |
| { |
| char *file, *comment; |
| RSA *public_key; |
| struct stat st; |
| |
| file = get_filename(pw, "Enter file in which the key is"); |
| if (stat(file, &st) < 0) |
| { |
| perror(file); |
| exit(1); |
| } |
| public_key = RSA_new(); |
| if (!load_public_key(file, public_key, &comment)) { |
| char *cp, line[1024]; |
| BIGNUM *e, *n; |
| int dummy, invalid = 0; |
| FILE *f = fopen(file, "r"); |
| n = BN_new(); |
| e = BN_new(); |
| if (f && fgets(line, sizeof(line), f)) { |
| cp = line; |
| line[strlen(line)-1] = '\0'; |
| if (auth_rsa_read_key(&cp, &dummy, e, n)) { |
| public_key->e = e; |
| public_key->n = n; |
| comment = xstrdup(cp ? cp : "no comment"); |
| } else { |
| invalid = 1; |
| } |
| } else { |
| invalid = 1; |
| } |
| if (invalid) { |
| printf("%s is not a valid key file.\n", file); |
| BN_free(e); |
| BN_free(n); |
| exit(1); |
| } |
| } |
| |
| printf("%d %s %s\n", BN_num_bits(public_key->n), |
| fingerprint(public_key->e, public_key->n), |
| comment); |
| RSA_free(public_key); |
| exit(0); |
| } |
| |
| |
| void |
| do_change_passphrase(struct passwd *pw) |
| { |
| char *file, *comment; |
| char *old_passphrase, *passphrase1, *passphrase2; |
| struct stat st; |
| RSA *private_key; |
| |
| file = get_filename(pw, "Enter file in which the key is"); |
| /* Check if the file exists. */ |
| if (stat(file, &st) < 0) |
| { |
| perror(file); |
| exit(1); |
| } |
| |
| /* Try to load the public key from the file the verify that it is |
| readable and of the proper format. */ |
| public_key = RSA_new(); |
| if (!load_public_key(file, public_key, NULL)) |
| { |
| printf("%s is not a valid key file.\n", file); |
| exit(1); |
| } |
| /* Clear the public key since we are just about to load the whole file. */ |
| RSA_free(public_key); |
| |
| /* Try to load the file with empty passphrase. */ |
| private_key = RSA_new(); |
| if (!load_private_key(file, "", private_key, &comment)) { |
| /* Read passphrase from the user. */ |
| if (identity_passphrase) |
| old_passphrase = xstrdup(identity_passphrase); |
| else |
| old_passphrase = read_passphrase("Enter old passphrase: ", 1); |
| /* Try to load using the passphrase. */ |
| if (!load_private_key(file, old_passphrase, private_key, &comment)) |
| { |
| memset(old_passphrase, 0, strlen(old_passphrase)); |
| xfree(old_passphrase); |
| printf("Bad passphrase.\n"); |
| exit(1); |
| } |
| /* Destroy the passphrase. */ |
| memset(old_passphrase, 0, strlen(old_passphrase)); |
| xfree(old_passphrase); |
| } |
| printf("Key has comment '%s'\n", comment); |
| |
| /* Ask the new passphrase (twice). */ |
| if (identity_new_passphrase) |
| { |
| passphrase1 = xstrdup(identity_new_passphrase); |
| passphrase2 = NULL; |
| } |
| else |
| { |
| passphrase1 = |
| read_passphrase("Enter new passphrase (empty for no passphrase): ", 1); |
| passphrase2 = read_passphrase("Enter same passphrase again: ", 1); |
| |
| /* Verify that they are the same. */ |
| if (strcmp(passphrase1, passphrase2) != 0) |
| { |
| memset(passphrase1, 0, strlen(passphrase1)); |
| memset(passphrase2, 0, strlen(passphrase2)); |
| xfree(passphrase1); |
| xfree(passphrase2); |
| printf("Pass phrases do not match. Try again.\n"); |
| exit(1); |
| } |
| /* Destroy the other copy. */ |
| memset(passphrase2, 0, strlen(passphrase2)); |
| xfree(passphrase2); |
| } |
| |
| /* Save the file using the new passphrase. */ |
| if (!save_private_key(file, passphrase1, private_key, comment)) |
| { |
| printf("Saving the key failed: %s: %s.\n", |
| file, strerror(errno)); |
| memset(passphrase1, 0, strlen(passphrase1)); |
| xfree(passphrase1); |
| RSA_free(private_key); |
| xfree(comment); |
| exit(1); |
| } |
| /* Destroy the passphrase and the copy of the key in memory. */ |
| memset(passphrase1, 0, strlen(passphrase1)); |
| xfree(passphrase1); |
| RSA_free(private_key); /* Destroys contents */ |
| xfree(comment); |
| |
| printf("Your identification has been saved with the new passphrase.\n"); |
| exit(0); |
| } |
| |
| /* Change the comment of a private key file. */ |
| |
| void |
| do_change_comment(struct passwd *pw) |
| { |
| char new_comment[1024], *file, *comment; |
| RSA *private_key; |
| char *passphrase; |
| struct stat st; |
| FILE *f; |
| char *tmpbuf; |
| |
| file = get_filename(pw, "Enter file in which the key is"); |
| /* Check if the file exists. */ |
| if (stat(file, &st) < 0) |
| { |
| perror(file); |
| exit(1); |
| } |
| |
| /* Try to load the public key from the file the verify that it is |
| readable and of the proper format. */ |
| public_key = RSA_new(); |
| if (!load_public_key(file, public_key, NULL)) |
| { |
| printf("%s is not a valid key file.\n", file); |
| exit(1); |
| } |
| |
| private_key = RSA_new(); |
| /* Try to load the file with empty passphrase. */ |
| if (load_private_key(file, "", private_key, &comment)) |
| passphrase = xstrdup(""); |
| else |
| { |
| /* Read passphrase from the user. */ |
| if (identity_passphrase) |
| passphrase = xstrdup(identity_passphrase); |
| else |
| if (identity_new_passphrase) |
| passphrase = xstrdup(identity_new_passphrase); |
| else |
| passphrase = read_passphrase("Enter passphrase: ", 1); |
| /* Try to load using the passphrase. */ |
| if (!load_private_key(file, passphrase, private_key, &comment)) |
| { |
| memset(passphrase, 0, strlen(passphrase)); |
| xfree(passphrase); |
| printf("Bad passphrase.\n"); |
| exit(1); |
| } |
| } |
| printf("Key now has comment '%s'\n", comment); |
| |
| if (identity_comment) |
| { |
| strlcpy(new_comment, identity_comment, sizeof(new_comment)); |
| } |
| else |
| { |
| printf("Enter new comment: "); |
| fflush(stdout); |
| if (!fgets(new_comment, sizeof(new_comment), stdin)) |
| { |
| memset(passphrase, 0, strlen(passphrase)); |
| RSA_free(private_key); |
| exit(1); |
| } |
| |
| /* Remove terminating newline from comment. */ |
| if (strchr(new_comment, '\n')) |
| *strchr(new_comment, '\n') = 0; |
| } |
| |
| /* Save the file using the new passphrase. */ |
| if (!save_private_key(file, passphrase, private_key, new_comment)) |
| { |
| printf("Saving the key failed: %s: %s.\n", |
| file, strerror(errno)); |
| memset(passphrase, 0, strlen(passphrase)); |
| xfree(passphrase); |
| RSA_free(private_key); |
| xfree(comment); |
| exit(1); |
| } |
| |
| /* Destroy the passphrase and the private key in memory. */ |
| memset(passphrase, 0, strlen(passphrase)); |
| xfree(passphrase); |
| RSA_free(private_key); |
| |
| /* Save the public key in text format in a file with the same name but |
| .pub appended. */ |
| strcat(file, ".pub"); |
| f = fopen(file, "w"); |
| if (!f) |
| { |
| printf("Could not save your public key in %s\n", file); |
| exit(1); |
| } |
| fprintf(f, "%d ", BN_num_bits(public_key->n)); |
| tmpbuf = BN_bn2dec(public_key->e); |
| fprintf(f, "%s ", tmpbuf); |
| free (tmpbuf); |
| tmpbuf = BN_bn2dec(public_key->n); |
| fprintf(f, "%s %s\n", tmpbuf, new_comment); |
| free (tmpbuf); |
| fclose(f); |
| |
| xfree(comment); |
| |
| printf("The comment in your key file has been changed.\n"); |
| exit(0); |
| } |
| |
| /* Main program for key management. */ |
| |
| int |
| main(int ac, char **av) |
| { |
| char buf[16384], buf2[1024], *passphrase1, *passphrase2; |
| struct passwd *pw; |
| char *file, *tmpbuf; |
| int opt; |
| struct stat st; |
| FILE *f; |
| char hostname[MAXHOSTNAMELEN]; |
| extern int optind; |
| extern char *optarg; |
| |
| /* check if RSA support exists */ |
| if (rsa_alive() == 0) { |
| extern char *__progname; |
| |
| fprintf(stderr, |
| "%s: no RSA support in libssl and libcrypto. See ssl(8).\n", |
| __progname); |
| exit(1); |
| } |
| |
| /* Get user\'s passwd structure. We need this for the home directory. */ |
| pw = getpwuid(getuid()); |
| if (!pw) |
| { |
| printf("You don't exist, go away!\n"); |
| exit(1); |
| } |
| |
| /* Create ~/.ssh directory if it doesn\'t already exist. */ |
| snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir, SSH_USER_DIR); |
| if (stat(buf, &st) < 0) |
| if (mkdir(buf, 0755) < 0) |
| error("Could not create directory '%s'.", buf); |
| |
| /* Parse command line arguments. */ |
| while ((opt = getopt(ac, av, "qpclb:f:P:N:C:")) != EOF) |
| { |
| switch (opt) |
| { |
| case 'b': |
| bits = atoi(optarg); |
| if (bits < 512 || bits > 32768) |
| { |
| printf("Bits has bad value.\n"); |
| exit(1); |
| } |
| break; |
| |
| case 'l': |
| print_fingerprint = 1; |
| break; |
| |
| case 'p': |
| change_passphrase = 1; |
| break; |
| |
| case 'c': |
| change_comment = 1; |
| break; |
| |
| case 'f': |
| identity_file = optarg; |
| break; |
| |
| case 'P': |
| identity_passphrase = optarg; |
| break; |
| |
| case 'N': |
| identity_new_passphrase = optarg; |
| break; |
| |
| case 'C': |
| identity_comment = optarg; |
| break; |
| |
| case 'q': |
| quiet = 1; |
| break; |
| |
| case '?': |
| default: |
| printf("ssh-keygen version %s\n", SSH_VERSION); |
| printf("Usage: %s [-b bits] [-p] [-c] [-f file] [-P pass] [-N new-pass] [-C comment]\n", av[0]); |
| exit(1); |
| } |
| } |
| if (optind < ac) |
| { |
| printf("Too many arguments.\n"); |
| exit(1); |
| } |
| if (change_passphrase && change_comment) |
| { |
| printf("Can only have one of -p and -c.\n"); |
| exit(1); |
| } |
| |
| if (print_fingerprint) |
| do_fingerprint(pw); |
| |
| /* If the user requested to change the passphrase, do it now. This |
| function never returns. */ |
| if (change_passphrase) |
| do_change_passphrase(pw); |
| |
| /* If the user requested to change the comment, do it now. This function |
| never returns. */ |
| if (change_comment) |
| do_change_comment(pw); |
| |
| arc4random_stir(); |
| |
| if (quiet) |
| rsa_set_verbose(0); |
| |
| /* Generate the rsa key pair. */ |
| private_key = RSA_new(); |
| public_key = RSA_new(); |
| rsa_generate_key(private_key, public_key, bits); |
| |
| ask_file_again: |
| |
| file = get_filename(pw, "Enter file in which to save the key"); |
| |
| /* If the file aready exists, ask the user to confirm. */ |
| if (stat(file, &st) >= 0) |
| { |
| printf("%s already exists.\n", file); |
| printf("Overwrite (y/n)? "); |
| fflush(stdout); |
| if (fgets(buf2, sizeof(buf2), stdin) == NULL) |
| exit(1); |
| if (buf2[0] != 'y' && buf2[0] != 'Y') |
| exit(1); |
| } |
| |
| /* Ask for a passphrase (twice). */ |
| if (identity_passphrase) |
| passphrase1 = xstrdup(identity_passphrase); |
| else |
| if (identity_new_passphrase) |
| passphrase1 = xstrdup(identity_new_passphrase); |
| else |
| { |
| passphrase_again: |
| passphrase1 = |
| read_passphrase("Enter passphrase (empty for no passphrase): ", 1); |
| passphrase2 = read_passphrase("Enter same passphrase again: ", 1); |
| if (strcmp(passphrase1, passphrase2) != 0) |
| { |
| /* The passphrases do not match. Clear them and retry. */ |
| memset(passphrase1, 0, strlen(passphrase1)); |
| memset(passphrase2, 0, strlen(passphrase2)); |
| xfree(passphrase1); |
| xfree(passphrase2); |
| printf("Passphrases do not match. Try again.\n"); |
| goto passphrase_again; |
| } |
| /* Clear the other copy of the passphrase. */ |
| memset(passphrase2, 0, strlen(passphrase2)); |
| xfree(passphrase2); |
| } |
| |
| /* Create default commend field for the passphrase. The user can later |
| edit this field. */ |
| if (identity_comment) |
| { |
| strlcpy(buf2, identity_comment, sizeof(buf2)); |
| } |
| else |
| { |
| if (gethostname(hostname, sizeof(hostname)) < 0) |
| { |
| perror("gethostname"); |
| exit(1); |
| } |
| snprintf(buf2, sizeof buf2, "%s@%s", pw->pw_name, hostname); |
| } |
| |
| /* Save the key with the given passphrase and comment. */ |
| if (!save_private_key(file, passphrase1, private_key, buf2)) |
| { |
| printf("Saving the key failed: %s: %s.\n", |
| file, strerror(errno)); |
| memset(passphrase1, 0, strlen(passphrase1)); |
| xfree(passphrase1); |
| xfree(file); |
| goto ask_file_again; |
| } |
| /* Clear the passphrase. */ |
| memset(passphrase1, 0, strlen(passphrase1)); |
| xfree(passphrase1); |
| |
| /* Clear the private key and the random number generator. */ |
| RSA_free(private_key); |
| arc4random_stir(); |
| |
| if (!quiet) |
| printf("Your identification has been saved in %s.\n", file); |
| |
| /* Display the public key on the screen. */ |
| if (!quiet) { |
| printf("Your public key is:\n"); |
| printf("%d ", BN_num_bits(public_key->n)); |
| tmpbuf = BN_bn2dec(public_key->e); |
| printf("%s ", tmpbuf); |
| free(tmpbuf); |
| tmpbuf = BN_bn2dec(public_key->n); |
| printf("%s %s\n", tmpbuf, buf2); |
| free(tmpbuf); |
| } |
| |
| /* Save the public key in text format in a file with the same name but |
| .pub appended. */ |
| file = xrealloc(file, strlen(file) + 5); |
| strcat(file, ".pub"); |
| f = fopen(file, "w"); |
| if (!f) |
| { |
| printf("Could not save your public key in %s\n", file); |
| exit(1); |
| } |
| fprintf(f, "%d ", BN_num_bits(public_key->n)); |
| tmpbuf = BN_bn2dec(public_key->e); |
| fprintf(f, "%s ", tmpbuf); |
| free(tmpbuf); |
| tmpbuf = BN_bn2dec(public_key->n); |
| fprintf(f, "%s %s\n", tmpbuf, buf2); |
| free(tmpbuf); |
| fclose(f); |
| |
| if (!quiet) |
| printf("Your public key has been saved in %s\n", file); |
| |
| exit(0); |
| } |