ssh-keygen.c revision 98937
1/*
2 * Author: Tatu Ylonen <ylo@cs.hut.fi>
3 * Copyright (c) 1994 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4 *                    All rights reserved
5 * Identity and host key generation and maintenance.
6 *
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".
12 */
13
14#include "includes.h"
15RCSID("$OpenBSD: ssh-keygen.c,v 1.100 2002/06/19 00:27:55 deraadt Exp $");
16
17#include <openssl/evp.h>
18#include <openssl/pem.h>
19
20#include "xmalloc.h"
21#include "key.h"
22#include "rsa.h"
23#include "authfile.h"
24#include "uuencode.h"
25#include "buffer.h"
26#include "bufaux.h"
27#include "pathnames.h"
28#include "log.h"
29#include "readpass.h"
30
31#ifdef SMARTCARD
32#include "scard.h"
33#endif
34
35/* Number of bits in the RSA/DSA key.  This value can be changed on the command line. */
36int bits = 1024;
37
38/*
39 * Flag indicating that we just want to change the passphrase.  This can be
40 * set on the command line.
41 */
42int change_passphrase = 0;
43
44/*
45 * Flag indicating that we just want to change the comment.  This can be set
46 * on the command line.
47 */
48int change_comment = 0;
49
50int quiet = 0;
51
52/* Flag indicating that we just want to see the key fingerprint */
53int print_fingerprint = 0;
54int print_bubblebabble = 0;
55
56/* The identity file name, given on the command line or entered by the user. */
57char identity_file[1024];
58int have_identity = 0;
59
60/* This is set to the passphrase if given on the command line. */
61char *identity_passphrase = NULL;
62
63/* This is set to the new passphrase if given on the command line. */
64char *identity_new_passphrase = NULL;
65
66/* This is set to the new comment if given on the command line. */
67char *identity_comment = NULL;
68
69/* Dump public key file in format used by real and the original SSH 2 */
70int convert_to_ssh2 = 0;
71int convert_from_ssh2 = 0;
72int print_public = 0;
73
74char *key_type_name = NULL;
75
76/* argv0 */
77#ifdef HAVE___PROGNAME
78extern char *__progname;
79#else
80char *__progname;
81#endif
82
83char hostname[MAXHOSTNAMELEN];
84
85static void
86ask_filename(struct passwd *pw, const char *prompt)
87{
88	char buf[1024];
89	char *name = NULL;
90
91	if (key_type_name == NULL)
92		name = _PATH_SSH_CLIENT_ID_RSA;
93	else
94		switch (key_type_from_name(key_type_name)) {
95		case KEY_RSA1:
96			name = _PATH_SSH_CLIENT_IDENTITY;
97			break;
98		case KEY_DSA:
99			name = _PATH_SSH_CLIENT_ID_DSA;
100			break;
101		case KEY_RSA:
102			name = _PATH_SSH_CLIENT_ID_RSA;
103			break;
104		default:
105			fprintf(stderr, "bad key type");
106			exit(1);
107			break;
108		}
109
110	snprintf(identity_file, sizeof(identity_file), "%s/%s", pw->pw_dir, name);
111	fprintf(stderr, "%s (%s): ", prompt, identity_file);
112	fflush(stderr);
113	if (fgets(buf, sizeof(buf), stdin) == NULL)
114		exit(1);
115	if (strchr(buf, '\n'))
116		*strchr(buf, '\n') = 0;
117	if (strcmp(buf, "") != 0)
118		strlcpy(identity_file, buf, sizeof(identity_file));
119	have_identity = 1;
120}
121
122static Key *
123load_identity(char *filename)
124{
125	char *pass;
126	Key *prv;
127
128	prv = key_load_private(filename, "", NULL);
129	if (prv == NULL) {
130		if (identity_passphrase)
131			pass = xstrdup(identity_passphrase);
132		else
133			pass = read_passphrase("Enter passphrase: ",
134			    RP_ALLOW_STDIN);
135		prv = key_load_private(filename, pass, NULL);
136		memset(pass, 0, strlen(pass));
137		xfree(pass);
138	}
139	return prv;
140}
141
142#define SSH_COM_PUBLIC_BEGIN		"---- BEGIN SSH2 PUBLIC KEY ----"
143#define SSH_COM_PUBLIC_END		"---- END SSH2 PUBLIC KEY ----"
144#define SSH_COM_PRIVATE_BEGIN		"---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----"
145#define	SSH_COM_PRIVATE_KEY_MAGIC	0x3f6ff9eb
146
147static void
148do_convert_to_ssh2(struct passwd *pw)
149{
150	Key *k;
151	u_int len;
152	u_char *blob;
153	struct stat st;
154
155	if (!have_identity)
156		ask_filename(pw, "Enter file in which the key is");
157	if (stat(identity_file, &st) < 0) {
158		perror(identity_file);
159		exit(1);
160	}
161	if ((k = key_load_public(identity_file, NULL)) == NULL) {
162		if ((k = load_identity(identity_file)) == NULL) {
163			fprintf(stderr, "load failed\n");
164			exit(1);
165		}
166	}
167	if (key_to_blob(k, &blob, &len) <= 0) {
168		fprintf(stderr, "key_to_blob failed\n");
169		exit(1);
170	}
171	fprintf(stdout, "%s\n", SSH_COM_PUBLIC_BEGIN);
172	fprintf(stdout,
173	    "Comment: \"%d-bit %s, converted from OpenSSH by %s@%s\"\n",
174	    key_size(k), key_type(k),
175	    pw->pw_name, hostname);
176	dump_base64(stdout, blob, len);
177	fprintf(stdout, "%s\n", SSH_COM_PUBLIC_END);
178	key_free(k);
179	xfree(blob);
180	exit(0);
181}
182
183static void
184buffer_get_bignum_bits(Buffer *b, BIGNUM *value)
185{
186	int bits = buffer_get_int(b);
187	int bytes = (bits + 7) / 8;
188
189	if (buffer_len(b) < bytes)
190		fatal("buffer_get_bignum_bits: input buffer too small: "
191		    "need %d have %d", bytes, buffer_len(b));
192	BN_bin2bn(buffer_ptr(b), bytes, value);
193	buffer_consume(b, bytes);
194}
195
196static Key *
197do_convert_private_ssh2_from_blob(u_char *blob, u_int blen)
198{
199	Buffer b;
200	Key *key = NULL;
201	char *type, *cipher;
202	u_char *sig, data[] = "abcde12345";
203	int magic, rlen, ktype, i1, i2, i3, i4;
204	u_int slen;
205	u_long e;
206
207	buffer_init(&b);
208	buffer_append(&b, blob, blen);
209
210	magic  = buffer_get_int(&b);
211	if (magic != SSH_COM_PRIVATE_KEY_MAGIC) {
212		error("bad magic 0x%x != 0x%x", magic, SSH_COM_PRIVATE_KEY_MAGIC);
213		buffer_free(&b);
214		return NULL;
215	}
216	i1 = buffer_get_int(&b);
217	type   = buffer_get_string(&b, NULL);
218	cipher = buffer_get_string(&b, NULL);
219	i2 = buffer_get_int(&b);
220	i3 = buffer_get_int(&b);
221	i4 = buffer_get_int(&b);
222	debug("ignore (%d %d %d %d)", i1,i2,i3,i4);
223	if (strcmp(cipher, "none") != 0) {
224		error("unsupported cipher %s", cipher);
225		xfree(cipher);
226		buffer_free(&b);
227		xfree(type);
228		return NULL;
229	}
230	xfree(cipher);
231
232	if (strstr(type, "dsa")) {
233		ktype = KEY_DSA;
234	} else if (strstr(type, "rsa")) {
235		ktype = KEY_RSA;
236	} else {
237		xfree(type);
238		return NULL;
239	}
240	key = key_new_private(ktype);
241	xfree(type);
242
243	switch (key->type) {
244	case KEY_DSA:
245		buffer_get_bignum_bits(&b, key->dsa->p);
246		buffer_get_bignum_bits(&b, key->dsa->g);
247		buffer_get_bignum_bits(&b, key->dsa->q);
248		buffer_get_bignum_bits(&b, key->dsa->pub_key);
249		buffer_get_bignum_bits(&b, key->dsa->priv_key);
250		break;
251	case KEY_RSA:
252		e  = buffer_get_char(&b);
253		debug("e %lx", e);
254		if (e < 30) {
255			e <<= 8;
256			e += buffer_get_char(&b);
257			debug("e %lx", e);
258			e <<= 8;
259			e += buffer_get_char(&b);
260			debug("e %lx", e);
261		}
262		if (!BN_set_word(key->rsa->e, e)) {
263			buffer_free(&b);
264			key_free(key);
265			return NULL;
266		}
267		buffer_get_bignum_bits(&b, key->rsa->d);
268		buffer_get_bignum_bits(&b, key->rsa->n);
269		buffer_get_bignum_bits(&b, key->rsa->iqmp);
270		buffer_get_bignum_bits(&b, key->rsa->q);
271		buffer_get_bignum_bits(&b, key->rsa->p);
272		rsa_generate_additional_parameters(key->rsa);
273		break;
274	}
275	rlen = buffer_len(&b);
276	if (rlen != 0)
277		error("do_convert_private_ssh2_from_blob: "
278		    "remaining bytes in key blob %d", rlen);
279	buffer_free(&b);
280
281	/* try the key */
282	key_sign(key, &sig, &slen, data, sizeof(data));
283	key_verify(key, sig, slen, data, sizeof(data));
284	xfree(sig);
285	return key;
286}
287
288static void
289do_convert_from_ssh2(struct passwd *pw)
290{
291	Key *k;
292	int blen;
293	u_int len;
294	char line[1024], *p;
295	u_char blob[8096];
296	char encoded[8096];
297	struct stat st;
298	int escaped = 0, private = 0, ok;
299	FILE *fp;
300
301	if (!have_identity)
302		ask_filename(pw, "Enter file in which the key is");
303	if (stat(identity_file, &st) < 0) {
304		perror(identity_file);
305		exit(1);
306	}
307	fp = fopen(identity_file, "r");
308	if (fp == NULL) {
309		perror(identity_file);
310		exit(1);
311	}
312	encoded[0] = '\0';
313	while (fgets(line, sizeof(line), fp)) {
314		if (!(p = strchr(line, '\n'))) {
315			fprintf(stderr, "input line too long.\n");
316			exit(1);
317		}
318		if (p > line && p[-1] == '\\')
319			escaped++;
320		if (strncmp(line, "----", 4) == 0 ||
321		    strstr(line, ": ") != NULL) {
322			if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
323				private = 1;
324			if (strstr(line, " END ") != NULL) {
325				break;
326			}
327			/* fprintf(stderr, "ignore: %s", line); */
328			continue;
329		}
330		if (escaped) {
331			escaped--;
332			/* fprintf(stderr, "escaped: %s", line); */
333			continue;
334		}
335		*p = '\0';
336		strlcat(encoded, line, sizeof(encoded));
337	}
338	len = strlen(encoded);
339	if (((len % 4) == 3) &&
340	    (encoded[len-1] == '=') &&
341	    (encoded[len-2] == '=') &&
342	    (encoded[len-3] == '='))
343		encoded[len-3] = '\0';
344	blen = uudecode(encoded, blob, sizeof(blob));
345	if (blen < 0) {
346		fprintf(stderr, "uudecode failed.\n");
347		exit(1);
348	}
349	k = private ?
350	    do_convert_private_ssh2_from_blob(blob, blen) :
351	    key_from_blob(blob, blen);
352	if (k == NULL) {
353		fprintf(stderr, "decode blob failed.\n");
354		exit(1);
355	}
356	ok = private ?
357	    (k->type == KEY_DSA ?
358		 PEM_write_DSAPrivateKey(stdout, k->dsa, NULL, NULL, 0, NULL, NULL) :
359		 PEM_write_RSAPrivateKey(stdout, k->rsa, NULL, NULL, 0, NULL, NULL)) :
360	    key_write(k, stdout);
361	if (!ok) {
362		fprintf(stderr, "key write failed");
363		exit(1);
364	}
365	key_free(k);
366	if (!private)
367		fprintf(stdout, "\n");
368	fclose(fp);
369	exit(0);
370}
371
372static void
373do_print_public(struct passwd *pw)
374{
375	Key *prv;
376	struct stat st;
377
378	if (!have_identity)
379		ask_filename(pw, "Enter file in which the key is");
380	if (stat(identity_file, &st) < 0) {
381		perror(identity_file);
382		exit(1);
383	}
384	prv = load_identity(identity_file);
385	if (prv == NULL) {
386		fprintf(stderr, "load failed\n");
387		exit(1);
388	}
389	if (!key_write(prv, stdout))
390		fprintf(stderr, "key_write failed");
391	key_free(prv);
392	fprintf(stdout, "\n");
393	exit(0);
394}
395
396#ifdef SMARTCARD
397static void
398do_upload(struct passwd *pw, const char *sc_reader_id)
399{
400	Key *prv = NULL;
401	struct stat st;
402	int ret;
403
404	if (!have_identity)
405		ask_filename(pw, "Enter file in which the key is");
406	if (stat(identity_file, &st) < 0) {
407		perror(identity_file);
408		exit(1);
409	}
410	prv = load_identity(identity_file);
411	if (prv == NULL) {
412		error("load failed");
413		exit(1);
414	}
415	ret = sc_put_key(prv, sc_reader_id);
416	key_free(prv);
417	if (ret < 0)
418		exit(1);
419	log("loading key done");
420	exit(0);
421}
422
423static void
424do_download(struct passwd *pw, const char *sc_reader_id)
425{
426	Key **keys = NULL;
427	int i;
428
429	keys = sc_get_keys(sc_reader_id, NULL);
430	if (keys == NULL)
431		fatal("cannot read public key from smartcard");
432	for (i = 0; keys[i]; i++) {
433		key_write(keys[i], stdout);
434		key_free(keys[i]);
435		fprintf(stdout, "\n");
436	}
437	xfree(keys);
438	exit(0);
439}
440#endif /* SMARTCARD */
441
442static void
443do_fingerprint(struct passwd *pw)
444{
445	FILE *f;
446	Key *public;
447	char *comment = NULL, *cp, *ep, line[16*1024], *fp;
448	int i, skip = 0, num = 1, invalid = 1;
449	enum fp_rep rep;
450	enum fp_type fptype;
451	struct stat st;
452
453	fptype = print_bubblebabble ? SSH_FP_SHA1 : SSH_FP_MD5;
454	rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_HEX;
455
456	if (!have_identity)
457		ask_filename(pw, "Enter file in which the key is");
458	if (stat(identity_file, &st) < 0) {
459		perror(identity_file);
460		exit(1);
461	}
462	public = key_load_public(identity_file, &comment);
463	if (public != NULL) {
464		fp = key_fingerprint(public, fptype, rep);
465		printf("%d %s %s\n", key_size(public), fp, comment);
466		key_free(public);
467		xfree(comment);
468		xfree(fp);
469		exit(0);
470	}
471	if (comment)
472		xfree(comment);
473
474	f = fopen(identity_file, "r");
475	if (f != NULL) {
476		while (fgets(line, sizeof(line), f)) {
477			i = strlen(line) - 1;
478			if (line[i] != '\n') {
479				error("line %d too long: %.40s...", num, line);
480				skip = 1;
481				continue;
482			}
483			num++;
484			if (skip) {
485				skip = 0;
486				continue;
487			}
488			line[i] = '\0';
489
490			/* Skip leading whitespace, empty and comment lines. */
491			for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
492				;
493			if (!*cp || *cp == '\n' || *cp == '#')
494				continue ;
495			i = strtol(cp, &ep, 10);
496			if (i == 0 || ep == NULL || (*ep != ' ' && *ep != '\t')) {
497				int quoted = 0;
498				comment = cp;
499				for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
500					if (*cp == '\\' && cp[1] == '"')
501						cp++;	/* Skip both */
502					else if (*cp == '"')
503						quoted = !quoted;
504				}
505				if (!*cp)
506					continue;
507				*cp++ = '\0';
508			}
509			ep = cp;
510			public = key_new(KEY_RSA1);
511			if (key_read(public, &cp) != 1) {
512				cp = ep;
513				key_free(public);
514				public = key_new(KEY_UNSPEC);
515				if (key_read(public, &cp) != 1) {
516					key_free(public);
517					continue;
518				}
519			}
520			comment = *cp ? cp : comment;
521			fp = key_fingerprint(public, fptype, rep);
522			printf("%d %s %s\n", key_size(public), fp,
523			    comment ? comment : "no comment");
524			xfree(fp);
525			key_free(public);
526			invalid = 0;
527		}
528		fclose(f);
529	}
530	if (invalid) {
531		printf("%s is not a public key file.\n", identity_file);
532		exit(1);
533	}
534	exit(0);
535}
536
537/*
538 * Perform changing a passphrase.  The argument is the passwd structure
539 * for the current user.
540 */
541static void
542do_change_passphrase(struct passwd *pw)
543{
544	char *comment;
545	char *old_passphrase, *passphrase1, *passphrase2;
546	struct stat st;
547	Key *private;
548
549	if (!have_identity)
550		ask_filename(pw, "Enter file in which the key is");
551	if (stat(identity_file, &st) < 0) {
552		perror(identity_file);
553		exit(1);
554	}
555	/* Try to load the file with empty passphrase. */
556	private = key_load_private(identity_file, "", &comment);
557	if (private == NULL) {
558		if (identity_passphrase)
559			old_passphrase = xstrdup(identity_passphrase);
560		else
561			old_passphrase =
562			    read_passphrase("Enter old passphrase: ",
563			    RP_ALLOW_STDIN);
564		private = key_load_private(identity_file, old_passphrase,
565		    &comment);
566		memset(old_passphrase, 0, strlen(old_passphrase));
567		xfree(old_passphrase);
568		if (private == NULL) {
569			printf("Bad passphrase.\n");
570			exit(1);
571		}
572	}
573	printf("Key has comment '%s'\n", comment);
574
575	/* Ask the new passphrase (twice). */
576	if (identity_new_passphrase) {
577		passphrase1 = xstrdup(identity_new_passphrase);
578		passphrase2 = NULL;
579	} else {
580		passphrase1 =
581			read_passphrase("Enter new passphrase (empty for no "
582			    "passphrase): ", RP_ALLOW_STDIN);
583		passphrase2 = read_passphrase("Enter same passphrase again: ",
584		    RP_ALLOW_STDIN);
585
586		/* Verify that they are the same. */
587		if (strcmp(passphrase1, passphrase2) != 0) {
588			memset(passphrase1, 0, strlen(passphrase1));
589			memset(passphrase2, 0, strlen(passphrase2));
590			xfree(passphrase1);
591			xfree(passphrase2);
592			printf("Pass phrases do not match.  Try again.\n");
593			exit(1);
594		}
595		/* Destroy the other copy. */
596		memset(passphrase2, 0, strlen(passphrase2));
597		xfree(passphrase2);
598	}
599
600	/* Save the file using the new passphrase. */
601	if (!key_save_private(private, identity_file, passphrase1, comment)) {
602		printf("Saving the key failed: %s.\n", identity_file);
603		memset(passphrase1, 0, strlen(passphrase1));
604		xfree(passphrase1);
605		key_free(private);
606		xfree(comment);
607		exit(1);
608	}
609	/* Destroy the passphrase and the copy of the key in memory. */
610	memset(passphrase1, 0, strlen(passphrase1));
611	xfree(passphrase1);
612	key_free(private);		 /* Destroys contents */
613	xfree(comment);
614
615	printf("Your identification has been saved with the new passphrase.\n");
616	exit(0);
617}
618
619/*
620 * Change the comment of a private key file.
621 */
622static void
623do_change_comment(struct passwd *pw)
624{
625	char new_comment[1024], *comment, *passphrase;
626	Key *private;
627	Key *public;
628	struct stat st;
629	FILE *f;
630	int fd;
631
632	if (!have_identity)
633		ask_filename(pw, "Enter file in which the key is");
634	if (stat(identity_file, &st) < 0) {
635		perror(identity_file);
636		exit(1);
637	}
638	private = key_load_private(identity_file, "", &comment);
639	if (private == NULL) {
640		if (identity_passphrase)
641			passphrase = xstrdup(identity_passphrase);
642		else if (identity_new_passphrase)
643			passphrase = xstrdup(identity_new_passphrase);
644		else
645			passphrase = read_passphrase("Enter passphrase: ",
646			    RP_ALLOW_STDIN);
647		/* Try to load using the passphrase. */
648		private = key_load_private(identity_file, passphrase, &comment);
649		if (private == NULL) {
650			memset(passphrase, 0, strlen(passphrase));
651			xfree(passphrase);
652			printf("Bad passphrase.\n");
653			exit(1);
654		}
655	} else {
656		passphrase = xstrdup("");
657	}
658	if (private->type != KEY_RSA1) {
659		fprintf(stderr, "Comments are only supported for RSA1 keys.\n");
660		key_free(private);
661		exit(1);
662	}
663	printf("Key now has comment '%s'\n", comment);
664
665	if (identity_comment) {
666		strlcpy(new_comment, identity_comment, sizeof(new_comment));
667	} else {
668		printf("Enter new comment: ");
669		fflush(stdout);
670		if (!fgets(new_comment, sizeof(new_comment), stdin)) {
671			memset(passphrase, 0, strlen(passphrase));
672			key_free(private);
673			exit(1);
674		}
675		if (strchr(new_comment, '\n'))
676			*strchr(new_comment, '\n') = 0;
677	}
678
679	/* Save the file using the new passphrase. */
680	if (!key_save_private(private, identity_file, passphrase, new_comment)) {
681		printf("Saving the key failed: %s.\n", identity_file);
682		memset(passphrase, 0, strlen(passphrase));
683		xfree(passphrase);
684		key_free(private);
685		xfree(comment);
686		exit(1);
687	}
688	memset(passphrase, 0, strlen(passphrase));
689	xfree(passphrase);
690	public = key_from_private(private);
691	key_free(private);
692
693	strlcat(identity_file, ".pub", sizeof(identity_file));
694	fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
695	if (fd == -1) {
696		printf("Could not save your public key in %s\n", identity_file);
697		exit(1);
698	}
699	f = fdopen(fd, "w");
700	if (f == NULL) {
701		printf("fdopen %s failed", identity_file);
702		exit(1);
703	}
704	if (!key_write(public, f))
705		fprintf(stderr, "write key failed");
706	key_free(public);
707	fprintf(f, " %s\n", new_comment);
708	fclose(f);
709
710	xfree(comment);
711
712	printf("The comment in your key file has been changed.\n");
713	exit(0);
714}
715
716static void
717usage(void)
718{
719	fprintf(stderr, "Usage: %s [options]\n", __progname);
720	fprintf(stderr, "Options:\n");
721	fprintf(stderr, "  -b bits     Number of bits in the key to create.\n");
722	fprintf(stderr, "  -c          Change comment in private and public key files.\n");
723	fprintf(stderr, "  -e          Convert OpenSSH to IETF SECSH key file.\n");
724	fprintf(stderr, "  -f filename Filename of the key file.\n");
725	fprintf(stderr, "  -i          Convert IETF SECSH to OpenSSH key file.\n");
726	fprintf(stderr, "  -l          Show fingerprint of key file.\n");
727	fprintf(stderr, "  -p          Change passphrase of private key file.\n");
728	fprintf(stderr, "  -q          Quiet.\n");
729	fprintf(stderr, "  -y          Read private key file and print public key.\n");
730	fprintf(stderr, "  -t type     Specify type of key to create.\n");
731	fprintf(stderr, "  -B          Show bubblebabble digest of key file.\n");
732	fprintf(stderr, "  -C comment  Provide new comment.\n");
733	fprintf(stderr, "  -N phrase   Provide new passphrase.\n");
734	fprintf(stderr, "  -P phrase   Provide old passphrase.\n");
735#ifdef SMARTCARD
736	fprintf(stderr, "  -D reader   Download public key from smartcard.\n");
737	fprintf(stderr, "  -U reader   Upload private key to smartcard.\n");
738#endif /* SMARTCARD */
739
740	exit(1);
741}
742
743/*
744 * Main program for key management.
745 */
746int
747main(int ac, char **av)
748{
749	char dotsshdir[MAXPATHLEN], comment[1024], *passphrase1, *passphrase2;
750	char *reader_id = NULL;
751	Key *private, *public;
752	struct passwd *pw;
753	struct stat st;
754	int opt, type, fd, download = 0;
755	FILE *f;
756
757	extern int optind;
758	extern char *optarg;
759
760	__progname = get_progname(av[0]);
761
762	SSLeay_add_all_algorithms();
763
764	/* we need this for the home * directory.  */
765	pw = getpwuid(getuid());
766	if (!pw) {
767		printf("You don't exist, go away!\n");
768		exit(1);
769	}
770	if (gethostname(hostname, sizeof(hostname)) < 0) {
771		perror("gethostname");
772		exit(1);
773	}
774
775	while ((opt = getopt(ac, av, "deiqpclBRxXyb:f:t:U:D:P:N:C:")) != -1) {
776		switch (opt) {
777		case 'b':
778			bits = atoi(optarg);
779			if (bits < 512 || bits > 32768) {
780				printf("Bits has bad value.\n");
781				exit(1);
782			}
783			break;
784		case 'l':
785			print_fingerprint = 1;
786			break;
787		case 'B':
788			print_bubblebabble = 1;
789			break;
790		case 'p':
791			change_passphrase = 1;
792			break;
793		case 'c':
794			change_comment = 1;
795			break;
796		case 'f':
797			strlcpy(identity_file, optarg, sizeof(identity_file));
798			have_identity = 1;
799			break;
800		case 'P':
801			identity_passphrase = optarg;
802			break;
803		case 'N':
804			identity_new_passphrase = optarg;
805			break;
806		case 'C':
807			identity_comment = optarg;
808			break;
809		case 'q':
810			quiet = 1;
811			break;
812		case 'R':
813			/* unused */
814			exit(0);
815			break;
816		case 'e':
817		case 'x':
818			/* export key */
819			convert_to_ssh2 = 1;
820			break;
821		case 'i':
822		case 'X':
823			/* import key */
824			convert_from_ssh2 = 1;
825			break;
826		case 'y':
827			print_public = 1;
828			break;
829		case 'd':
830			key_type_name = "dsa";
831			break;
832		case 't':
833			key_type_name = optarg;
834			break;
835		case 'D':
836			download = 1;
837		case 'U':
838			reader_id = optarg;
839			break;
840		case '?':
841		default:
842			usage();
843		}
844	}
845	if (optind < ac) {
846		printf("Too many arguments.\n");
847		usage();
848	}
849	if (change_passphrase && change_comment) {
850		printf("Can only have one of -p and -c.\n");
851		usage();
852	}
853	if (print_fingerprint || print_bubblebabble)
854		do_fingerprint(pw);
855	if (change_passphrase)
856		do_change_passphrase(pw);
857	if (convert_to_ssh2)
858		do_convert_to_ssh2(pw);
859	if (change_comment)
860		do_change_comment(pw);
861	if (print_public)
862		do_print_public(pw);
863	if (reader_id != NULL) {
864#ifdef SMARTCARD
865		if (download)
866			do_download(pw, reader_id);
867		else
868			do_upload(pw, reader_id);
869#else /* SMARTCARD */
870		fatal("no support for smartcards.");
871#endif /* SMARTCARD */
872	}
873
874	init_rng();
875	seed_rng();
876	arc4random_stir();
877
878	if (convert_from_ssh2)
879		do_convert_from_ssh2(pw);
880
881	if (key_type_name == NULL) {
882		printf("You must specify a key type (-t).\n");
883		usage();
884	}
885	type = key_type_from_name(key_type_name);
886	if (type == KEY_UNSPEC) {
887		fprintf(stderr, "unknown key type %s\n", key_type_name);
888		exit(1);
889	}
890	if (!quiet)
891		printf("Generating public/private %s key pair.\n", key_type_name);
892	private = key_generate(type, bits);
893	if (private == NULL) {
894		fprintf(stderr, "key_generate failed");
895		exit(1);
896	}
897	public  = key_from_private(private);
898
899	if (!have_identity)
900		ask_filename(pw, "Enter file in which to save the key");
901
902	/* Create ~/.ssh directory if it doesn\'t already exist. */
903	snprintf(dotsshdir, sizeof dotsshdir, "%s/%s", pw->pw_dir, _PATH_SSH_USER_DIR);
904	if (strstr(identity_file, dotsshdir) != NULL &&
905	    stat(dotsshdir, &st) < 0) {
906		if (mkdir(dotsshdir, 0700) < 0)
907			error("Could not create directory '%s'.", dotsshdir);
908		else if (!quiet)
909			printf("Created directory '%s'.\n", dotsshdir);
910	}
911	/* If the file already exists, ask the user to confirm. */
912	if (stat(identity_file, &st) >= 0) {
913		char yesno[3];
914		printf("%s already exists.\n", identity_file);
915		printf("Overwrite (y/n)? ");
916		fflush(stdout);
917		if (fgets(yesno, sizeof(yesno), stdin) == NULL)
918			exit(1);
919		if (yesno[0] != 'y' && yesno[0] != 'Y')
920			exit(1);
921	}
922	/* Ask for a passphrase (twice). */
923	if (identity_passphrase)
924		passphrase1 = xstrdup(identity_passphrase);
925	else if (identity_new_passphrase)
926		passphrase1 = xstrdup(identity_new_passphrase);
927	else {
928passphrase_again:
929		passphrase1 =
930			read_passphrase("Enter passphrase (empty for no "
931			    "passphrase): ", RP_ALLOW_STDIN);
932		passphrase2 = read_passphrase("Enter same passphrase again: ",
933		    RP_ALLOW_STDIN);
934		if (strcmp(passphrase1, passphrase2) != 0) {
935			/*
936			 * The passphrases do not match.  Clear them and
937			 * retry.
938			 */
939			memset(passphrase1, 0, strlen(passphrase1));
940			memset(passphrase2, 0, strlen(passphrase2));
941			xfree(passphrase1);
942			xfree(passphrase2);
943			printf("Passphrases do not match.  Try again.\n");
944			goto passphrase_again;
945		}
946		/* Clear the other copy of the passphrase. */
947		memset(passphrase2, 0, strlen(passphrase2));
948		xfree(passphrase2);
949	}
950
951	if (identity_comment) {
952		strlcpy(comment, identity_comment, sizeof(comment));
953	} else {
954		/* Create default commend field for the passphrase. */
955		snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
956	}
957
958	/* Save the key with the given passphrase and comment. */
959	if (!key_save_private(private, identity_file, passphrase1, comment)) {
960		printf("Saving the key failed: %s.\n", identity_file);
961		memset(passphrase1, 0, strlen(passphrase1));
962		xfree(passphrase1);
963		exit(1);
964	}
965	/* Clear the passphrase. */
966	memset(passphrase1, 0, strlen(passphrase1));
967	xfree(passphrase1);
968
969	/* Clear the private key and the random number generator. */
970	key_free(private);
971	arc4random_stir();
972
973	if (!quiet)
974		printf("Your identification has been saved in %s.\n", identity_file);
975
976	strlcat(identity_file, ".pub", sizeof(identity_file));
977	fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
978	if (fd == -1) {
979		printf("Could not save your public key in %s\n", identity_file);
980		exit(1);
981	}
982	f = fdopen(fd, "w");
983	if (f == NULL) {
984		printf("fdopen %s failed", identity_file);
985		exit(1);
986	}
987	if (!key_write(public, f))
988		fprintf(stderr, "write key failed");
989	fprintf(f, " %s\n", comment);
990	fclose(f);
991
992	if (!quiet) {
993		char *fp = key_fingerprint(public, SSH_FP_MD5, SSH_FP_HEX);
994		printf("Your public key has been saved in %s.\n",
995		    identity_file);
996		printf("The key fingerprint is:\n");
997		printf("%s %s\n", fp, comment);
998		xfree(fp);
999	}
1000
1001	key_free(public);
1002	exit(0);
1003}
1004