freebsd-skq/ssh-keygen.c
2008-07-23 09:15:38 +00:00

1449 lines
36 KiB
C

/* $OpenBSD: ssh-keygen.c,v 1.160 2007/01/21 01:41:54 stevesk Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1994 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
* Identity and host key generation and maintenance.
*
* As far as I am concerned, the code I have written for this software
* can be used freely for any purpose. Any derived versions of this
* software must be clearly marked as such, and if the derived work is
* incompatible with the protocol description in the RFC file, it must be
* called by a name other than "ssh" or "Secure Shell".
*/
#include "includes.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/param.h>
#include <openssl/evp.h>
#include <openssl/pem.h>
#include <errno.h>
#include <fcntl.h>
#include <netdb.h>
#ifdef HAVE_PATHS_H
# include <paths.h>
#endif
#include <pwd.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "xmalloc.h"
#include "key.h"
#include "rsa.h"
#include "authfile.h"
#include "uuencode.h"
#include "buffer.h"
#include "pathnames.h"
#include "log.h"
#include "misc.h"
#include "match.h"
#include "hostfile.h"
#include "dns.h"
#ifdef SMARTCARD
#include "scard.h"
#endif
/* Number of bits in the RSA/DSA key. This value can be set on the command line. */
#define DEFAULT_BITS 2048
#define DEFAULT_BITS_DSA 1024
u_int32_t bits = 0;
/*
* 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 want to hash a known_hosts file */
int hash_hosts = 0;
/* Flag indicating that we want lookup a host in known_hosts file */
int find_host = 0;
/* Flag indicating that we want to delete a host from a known_hosts file */
int delete_host = 0;
/* Flag indicating that we just want to see the key fingerprint */
int print_fingerprint = 0;
int print_bubblebabble = 0;
/* The identity file name, given on the command line or entered by the user. */
char identity_file[1024];
int have_identity = 0;
/* 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;
/* Dump public key file in format used by real and the original SSH 2 */
int convert_to_ssh2 = 0;
int convert_from_ssh2 = 0;
int print_public = 0;
int print_generic = 0;
char *key_type_name = NULL;
/* argv0 */
extern char *__progname;
char hostname[MAXHOSTNAMELEN];
/* moduli.c */
int gen_candidates(FILE *, u_int32_t, u_int32_t, BIGNUM *);
int prime_test(FILE *, FILE *, u_int32_t, u_int32_t);
static void
ask_filename(struct passwd *pw, const char *prompt)
{
char buf[1024];
char *name = NULL;
if (key_type_name == NULL)
name = _PATH_SSH_CLIENT_ID_RSA;
else {
switch (key_type_from_name(key_type_name)) {
case KEY_RSA1:
name = _PATH_SSH_CLIENT_IDENTITY;
break;
case KEY_DSA:
name = _PATH_SSH_CLIENT_ID_DSA;
break;
case KEY_RSA:
name = _PATH_SSH_CLIENT_ID_RSA;
break;
default:
fprintf(stderr, "bad key type");
exit(1);
break;
}
}
snprintf(identity_file, sizeof(identity_file), "%s/%s", pw->pw_dir, name);
fprintf(stderr, "%s (%s): ", prompt, identity_file);
if (fgets(buf, sizeof(buf), stdin) == NULL)
exit(1);
if (strchr(buf, '\n'))
*strchr(buf, '\n') = 0;
if (strcmp(buf, "") != 0)
strlcpy(identity_file, buf, sizeof(identity_file));
have_identity = 1;
}
static Key *
load_identity(char *filename)
{
char *pass;
Key *prv;
prv = key_load_private(filename, "", NULL);
if (prv == NULL) {
if (identity_passphrase)
pass = xstrdup(identity_passphrase);
else
pass = read_passphrase("Enter passphrase: ",
RP_ALLOW_STDIN);
prv = key_load_private(filename, pass, NULL);
memset(pass, 0, strlen(pass));
xfree(pass);
}
return prv;
}
#define SSH_COM_PUBLIC_BEGIN "---- BEGIN SSH2 PUBLIC KEY ----"
#define SSH_COM_PUBLIC_END "---- END SSH2 PUBLIC KEY ----"
#define SSH_COM_PRIVATE_BEGIN "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----"
#define SSH_COM_PRIVATE_KEY_MAGIC 0x3f6ff9eb
static void
do_convert_to_ssh2(struct passwd *pw)
{
Key *k;
u_int len;
u_char *blob;
struct stat st;
if (!have_identity)
ask_filename(pw, "Enter file in which the key is");
if (stat(identity_file, &st) < 0) {
perror(identity_file);
exit(1);
}
if ((k = key_load_public(identity_file, NULL)) == NULL) {
if ((k = load_identity(identity_file)) == NULL) {
fprintf(stderr, "load failed\n");
exit(1);
}
}
if (k->type == KEY_RSA1) {
fprintf(stderr, "version 1 keys are not supported\n");
exit(1);
}
if (key_to_blob(k, &blob, &len) <= 0) {
fprintf(stderr, "key_to_blob failed\n");
exit(1);
}
fprintf(stdout, "%s\n", SSH_COM_PUBLIC_BEGIN);
fprintf(stdout,
"Comment: \"%u-bit %s, converted from OpenSSH by %s@%s\"\n",
key_size(k), key_type(k),
pw->pw_name, hostname);
dump_base64(stdout, blob, len);
fprintf(stdout, "%s\n", SSH_COM_PUBLIC_END);
key_free(k);
xfree(blob);
exit(0);
}
static void
buffer_get_bignum_bits(Buffer *b, BIGNUM *value)
{
u_int bignum_bits = buffer_get_int(b);
u_int bytes = (bignum_bits + 7) / 8;
if (buffer_len(b) < bytes)
fatal("buffer_get_bignum_bits: input buffer too small: "
"need %d have %d", bytes, buffer_len(b));
if (BN_bin2bn(buffer_ptr(b), bytes, value) == NULL)
fatal("buffer_get_bignum_bits: BN_bin2bn failed");
buffer_consume(b, bytes);
}
static Key *
do_convert_private_ssh2_from_blob(u_char *blob, u_int blen)
{
Buffer b;
Key *key = NULL;
char *type, *cipher;
u_char *sig, data[] = "abcde12345";
int magic, rlen, ktype, i1, i2, i3, i4;
u_int slen;
u_long e;
buffer_init(&b);
buffer_append(&b, blob, blen);
magic = buffer_get_int(&b);
if (magic != SSH_COM_PRIVATE_KEY_MAGIC) {
error("bad magic 0x%x != 0x%x", magic, SSH_COM_PRIVATE_KEY_MAGIC);
buffer_free(&b);
return NULL;
}
i1 = buffer_get_int(&b);
type = buffer_get_string(&b, NULL);
cipher = buffer_get_string(&b, NULL);
i2 = buffer_get_int(&b);
i3 = buffer_get_int(&b);
i4 = buffer_get_int(&b);
debug("ignore (%d %d %d %d)", i1, i2, i3, i4);
if (strcmp(cipher, "none") != 0) {
error("unsupported cipher %s", cipher);
xfree(cipher);
buffer_free(&b);
xfree(type);
return NULL;
}
xfree(cipher);
if (strstr(type, "dsa")) {
ktype = KEY_DSA;
} else if (strstr(type, "rsa")) {
ktype = KEY_RSA;
} else {
buffer_free(&b);
xfree(type);
return NULL;
}
key = key_new_private(ktype);
xfree(type);
switch (key->type) {
case KEY_DSA:
buffer_get_bignum_bits(&b, key->dsa->p);
buffer_get_bignum_bits(&b, key->dsa->g);
buffer_get_bignum_bits(&b, key->dsa->q);
buffer_get_bignum_bits(&b, key->dsa->pub_key);
buffer_get_bignum_bits(&b, key->dsa->priv_key);
break;
case KEY_RSA:
e = buffer_get_char(&b);
debug("e %lx", e);
if (e < 30) {
e <<= 8;
e += buffer_get_char(&b);
debug("e %lx", e);
e <<= 8;
e += buffer_get_char(&b);
debug("e %lx", e);
}
if (!BN_set_word(key->rsa->e, e)) {
buffer_free(&b);
key_free(key);
return NULL;
}
buffer_get_bignum_bits(&b, key->rsa->d);
buffer_get_bignum_bits(&b, key->rsa->n);
buffer_get_bignum_bits(&b, key->rsa->iqmp);
buffer_get_bignum_bits(&b, key->rsa->q);
buffer_get_bignum_bits(&b, key->rsa->p);
rsa_generate_additional_parameters(key->rsa);
break;
}
rlen = buffer_len(&b);
if (rlen != 0)
error("do_convert_private_ssh2_from_blob: "
"remaining bytes in key blob %d", rlen);
buffer_free(&b);
/* try the key */
key_sign(key, &sig, &slen, data, sizeof(data));
key_verify(key, sig, slen, data, sizeof(data));
xfree(sig);
return key;
}
static int
get_line(FILE *fp, char *line, size_t len)
{
int c;
size_t pos = 0;
line[0] = '\0';
while ((c = fgetc(fp)) != EOF) {
if (pos >= len - 1) {
fprintf(stderr, "input line too long.\n");
exit(1);
}
switch (c) {
case '\r':
c = fgetc(fp);
if (c != EOF && c != '\n' && ungetc(c, fp) == EOF) {
fprintf(stderr, "unget: %s\n", strerror(errno));
exit(1);
}
return pos;
case '\n':
return pos;
}
line[pos++] = c;
line[pos] = '\0';
}
/* We reached EOF */
return -1;
}
static void
do_convert_from_ssh2(struct passwd *pw)
{
Key *k;
int blen;
u_int len;
char line[1024];
u_char blob[8096];
char encoded[8096];
struct stat st;
int escaped = 0, private = 0, ok;
FILE *fp;
if (!have_identity)
ask_filename(pw, "Enter file in which the key is");
if (stat(identity_file, &st) < 0) {
perror(identity_file);
exit(1);
}
fp = fopen(identity_file, "r");
if (fp == NULL) {
perror(identity_file);
exit(1);
}
encoded[0] = '\0';
while ((blen = get_line(fp, line, sizeof(line))) != -1) {
if (line[blen - 1] == '\\')
escaped++;
if (strncmp(line, "----", 4) == 0 ||
strstr(line, ": ") != NULL) {
if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
private = 1;
if (strstr(line, " END ") != NULL) {
break;
}
/* fprintf(stderr, "ignore: %s", line); */
continue;
}
if (escaped) {
escaped--;
/* fprintf(stderr, "escaped: %s", line); */
continue;
}
strlcat(encoded, line, sizeof(encoded));
}
len = strlen(encoded);
if (((len % 4) == 3) &&
(encoded[len-1] == '=') &&
(encoded[len-2] == '=') &&
(encoded[len-3] == '='))
encoded[len-3] = '\0';
blen = uudecode(encoded, blob, sizeof(blob));
if (blen < 0) {
fprintf(stderr, "uudecode failed.\n");
exit(1);
}
k = private ?
do_convert_private_ssh2_from_blob(blob, blen) :
key_from_blob(blob, blen);
if (k == NULL) {
fprintf(stderr, "decode blob failed.\n");
exit(1);
}
ok = private ?
(k->type == KEY_DSA ?
PEM_write_DSAPrivateKey(stdout, k->dsa, NULL, NULL, 0, NULL, NULL) :
PEM_write_RSAPrivateKey(stdout, k->rsa, NULL, NULL, 0, NULL, NULL)) :
key_write(k, stdout);
if (!ok) {
fprintf(stderr, "key write failed");
exit(1);
}
key_free(k);
if (!private)
fprintf(stdout, "\n");
fclose(fp);
exit(0);
}
static void
do_print_public(struct passwd *pw)
{
Key *prv;
struct stat st;
if (!have_identity)
ask_filename(pw, "Enter file in which the key is");
if (stat(identity_file, &st) < 0) {
perror(identity_file);
exit(1);
}
prv = load_identity(identity_file);
if (prv == NULL) {
fprintf(stderr, "load failed\n");
exit(1);
}
if (!key_write(prv, stdout))
fprintf(stderr, "key_write failed");
key_free(prv);
fprintf(stdout, "\n");
exit(0);
}
#ifdef SMARTCARD
static void
do_upload(struct passwd *pw, const char *sc_reader_id)
{
Key *prv = NULL;
struct stat st;
int ret;
if (!have_identity)
ask_filename(pw, "Enter file in which the key is");
if (stat(identity_file, &st) < 0) {
perror(identity_file);
exit(1);
}
prv = load_identity(identity_file);
if (prv == NULL) {
error("load failed");
exit(1);
}
ret = sc_put_key(prv, sc_reader_id);
key_free(prv);
if (ret < 0)
exit(1);
logit("loading key done");
exit(0);
}
static void
do_download(struct passwd *pw, const char *sc_reader_id)
{
Key **keys = NULL;
int i;
keys = sc_get_keys(sc_reader_id, NULL);
if (keys == NULL)
fatal("cannot read public key from smartcard");
for (i = 0; keys[i]; i++) {
key_write(keys[i], stdout);
key_free(keys[i]);
fprintf(stdout, "\n");
}
xfree(keys);
exit(0);
}
#endif /* SMARTCARD */
static void
do_fingerprint(struct passwd *pw)
{
FILE *f;
Key *public;
char *comment = NULL, *cp, *ep, line[16*1024], *fp;
int i, skip = 0, num = 1, invalid = 1;
enum fp_rep rep;
enum fp_type fptype;
struct stat st;
fptype = print_bubblebabble ? SSH_FP_SHA1 : SSH_FP_MD5;
rep = print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_HEX;
if (!have_identity)
ask_filename(pw, "Enter file in which the key is");
if (stat(identity_file, &st) < 0) {
perror(identity_file);
exit(1);
}
public = key_load_public(identity_file, &comment);
if (public != NULL) {
fp = key_fingerprint(public, fptype, rep);
printf("%u %s %s\n", key_size(public), fp, comment);
key_free(public);
xfree(comment);
xfree(fp);
exit(0);
}
if (comment) {
xfree(comment);
comment = NULL;
}
f = fopen(identity_file, "r");
if (f != NULL) {
while (fgets(line, sizeof(line), f)) {
i = strlen(line) - 1;
if (line[i] != '\n') {
error("line %d too long: %.40s...", num, line);
skip = 1;
continue;
}
num++;
if (skip) {
skip = 0;
continue;
}
line[i] = '\0';
/* Skip leading whitespace, empty and comment lines. */
for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
;
if (!*cp || *cp == '\n' || *cp == '#')
continue;
i = strtol(cp, &ep, 10);
if (i == 0 || ep == NULL || (*ep != ' ' && *ep != '\t')) {
int quoted = 0;
comment = cp;
for (; *cp && (quoted || (*cp != ' ' &&
*cp != '\t')); cp++) {
if (*cp == '\\' && cp[1] == '"')
cp++; /* Skip both */
else if (*cp == '"')
quoted = !quoted;
}
if (!*cp)
continue;
*cp++ = '\0';
}
ep = cp;
public = key_new(KEY_RSA1);
if (key_read(public, &cp) != 1) {
cp = ep;
key_free(public);
public = key_new(KEY_UNSPEC);
if (key_read(public, &cp) != 1) {
key_free(public);
continue;
}
}
comment = *cp ? cp : comment;
fp = key_fingerprint(public, fptype, rep);
printf("%u %s %s\n", key_size(public), fp,
comment ? comment : "no comment");
xfree(fp);
key_free(public);
invalid = 0;
}
fclose(f);
}
if (invalid) {
printf("%s is not a public key file.\n", identity_file);
exit(1);
}
exit(0);
}
static void
print_host(FILE *f, char *name, Key *public, int hash)
{
if (hash && (name = host_hash(name, NULL, 0)) == NULL)
fatal("hash_host failed");
fprintf(f, "%s ", name);
if (!key_write(public, f))
fatal("key_write failed");
fprintf(f, "\n");
}
static void
do_known_hosts(struct passwd *pw, const char *name)
{
FILE *in, *out = stdout;
Key *public;
char *cp, *cp2, *kp, *kp2;
char line[16*1024], tmp[MAXPATHLEN], old[MAXPATHLEN];
int c, i, skip = 0, inplace = 0, num = 0, invalid = 0, has_unhashed = 0;
if (!have_identity) {
cp = tilde_expand_filename(_PATH_SSH_USER_HOSTFILE, pw->pw_uid);
if (strlcpy(identity_file, cp, sizeof(identity_file)) >=
sizeof(identity_file))
fatal("Specified known hosts path too long");
xfree(cp);
have_identity = 1;
}
if ((in = fopen(identity_file, "r")) == NULL)
fatal("fopen: %s", strerror(errno));
/*
* Find hosts goes to stdout, hash and deletions happen in-place
* A corner case is ssh-keygen -HF foo, which should go to stdout
*/
if (!find_host && (hash_hosts || delete_host)) {
if (strlcpy(tmp, identity_file, sizeof(tmp)) >= sizeof(tmp) ||
strlcat(tmp, ".XXXXXXXXXX", sizeof(tmp)) >= sizeof(tmp) ||
strlcpy(old, identity_file, sizeof(old)) >= sizeof(old) ||
strlcat(old, ".old", sizeof(old)) >= sizeof(old))
fatal("known_hosts path too long");
umask(077);
if ((c = mkstemp(tmp)) == -1)
fatal("mkstemp: %s", strerror(errno));
if ((out = fdopen(c, "w")) == NULL) {
c = errno;
unlink(tmp);
fatal("fdopen: %s", strerror(c));
}
inplace = 1;
}
while (fgets(line, sizeof(line), in)) {
num++;
i = strlen(line) - 1;
if (line[i] != '\n') {
error("line %d too long: %.40s...", num, line);
skip = 1;
invalid = 1;
continue;
}
if (skip) {
skip = 0;
continue;
}
line[i] = '\0';
/* Skip leading whitespace, empty and comment lines. */
for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
;
if (!*cp || *cp == '\n' || *cp == '#') {
if (inplace)
fprintf(out, "%s\n", cp);
continue;
}
/* Find the end of the host name portion. */
for (kp = cp; *kp && *kp != ' ' && *kp != '\t'; kp++)
;
if (*kp == '\0' || *(kp + 1) == '\0') {
error("line %d missing key: %.40s...",
num, line);
invalid = 1;
continue;
}
*kp++ = '\0';
kp2 = kp;
public = key_new(KEY_RSA1);
if (key_read(public, &kp) != 1) {
kp = kp2;
key_free(public);
public = key_new(KEY_UNSPEC);
if (key_read(public, &kp) != 1) {
error("line %d invalid key: %.40s...",
num, line);
key_free(public);
invalid = 1;
continue;
}
}
if (*cp == HASH_DELIM) {
if (find_host || delete_host) {
cp2 = host_hash(name, cp, strlen(cp));
if (cp2 == NULL) {
error("line %d: invalid hashed "
"name: %.64s...", num, line);
invalid = 1;
continue;
}
c = (strcmp(cp2, cp) == 0);
if (find_host && c) {
printf("# Host %s found: "
"line %d type %s\n", name,
num, key_type(public));
print_host(out, cp, public, 0);
}
if (delete_host && !c)
print_host(out, cp, public, 0);
} else if (hash_hosts)
print_host(out, cp, public, 0);
} else {
if (find_host || delete_host) {
c = (match_hostname(name, cp,
strlen(cp)) == 1);
if (find_host && c) {
printf("# Host %s found: "
"line %d type %s\n", name,
num, key_type(public));
print_host(out, cp, public, hash_hosts);
}
if (delete_host && !c)
print_host(out, cp, public, 0);
} else if (hash_hosts) {
for (cp2 = strsep(&cp, ",");
cp2 != NULL && *cp2 != '\0';
cp2 = strsep(&cp, ",")) {
if (strcspn(cp2, "*?!") != strlen(cp2))
fprintf(stderr, "Warning: "
"ignoring host name with "
"metacharacters: %.64s\n",
cp2);
else
print_host(out, cp2, public, 1);
}
has_unhashed = 1;
}
}
key_free(public);
}
fclose(in);
if (invalid) {
fprintf(stderr, "%s is not a valid known_host file.\n",
identity_file);
if (inplace) {
fprintf(stderr, "Not replacing existing known_hosts "
"file because of errors\n");
fclose(out);
unlink(tmp);
}
exit(1);
}
if (inplace) {
fclose(out);
/* Backup existing file */
if (unlink(old) == -1 && errno != ENOENT)
fatal("unlink %.100s: %s", old, strerror(errno));
if (link(identity_file, old) == -1)
fatal("link %.100s to %.100s: %s", identity_file, old,
strerror(errno));
/* Move new one into place */
if (rename(tmp, identity_file) == -1) {
error("rename\"%s\" to \"%s\": %s", tmp, identity_file,
strerror(errno));
unlink(tmp);
unlink(old);
exit(1);
}
fprintf(stderr, "%s updated.\n", identity_file);
fprintf(stderr, "Original contents retained as %s\n", old);
if (has_unhashed) {
fprintf(stderr, "WARNING: %s contains unhashed "
"entries\n", old);
fprintf(stderr, "Delete this file to ensure privacy "
"of hostnames\n");
}
}
exit(0);
}
/*
* Perform changing a passphrase. The argument is the passwd structure
* for the current user.
*/
static void
do_change_passphrase(struct passwd *pw)
{
char *comment;
char *old_passphrase, *passphrase1, *passphrase2;
struct stat st;
Key *private;
if (!have_identity)
ask_filename(pw, "Enter file in which the key is");
if (stat(identity_file, &st) < 0) {
perror(identity_file);
exit(1);
}
/* Try to load the file with empty passphrase. */
private = key_load_private(identity_file, "", &comment);
if (private == NULL) {
if (identity_passphrase)
old_passphrase = xstrdup(identity_passphrase);
else
old_passphrase =
read_passphrase("Enter old passphrase: ",
RP_ALLOW_STDIN);
private = key_load_private(identity_file, old_passphrase,
&comment);
memset(old_passphrase, 0, strlen(old_passphrase));
xfree(old_passphrase);
if (private == NULL) {
printf("Bad passphrase.\n");
exit(1);
}
}
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): ", RP_ALLOW_STDIN);
passphrase2 = read_passphrase("Enter same passphrase again: ",
RP_ALLOW_STDIN);
/* 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 (!key_save_private(private, identity_file, passphrase1, comment)) {
printf("Saving the key failed: %s.\n", identity_file);
memset(passphrase1, 0, strlen(passphrase1));
xfree(passphrase1);
key_free(private);
xfree(comment);
exit(1);
}
/* Destroy the passphrase and the copy of the key in memory. */
memset(passphrase1, 0, strlen(passphrase1));
xfree(passphrase1);
key_free(private); /* Destroys contents */
xfree(comment);
printf("Your identification has been saved with the new passphrase.\n");
exit(0);
}
/*
* Print the SSHFP RR.
*/
static int
do_print_resource_record(struct passwd *pw, char *fname, char *hname)
{
Key *public;
char *comment = NULL;
struct stat st;
if (fname == NULL)
ask_filename(pw, "Enter file in which the key is");
if (stat(fname, &st) < 0) {
if (errno == ENOENT)
return 0;
perror(fname);
exit(1);
}
public = key_load_public(fname, &comment);
if (public != NULL) {
export_dns_rr(hname, public, stdout, print_generic);
key_free(public);
xfree(comment);
return 1;
}
if (comment)
xfree(comment);
printf("failed to read v2 public key from %s.\n", fname);
exit(1);
}
/*
* Change the comment of a private key file.
*/
static void
do_change_comment(struct passwd *pw)
{
char new_comment[1024], *comment, *passphrase;
Key *private;
Key *public;
struct stat st;
FILE *f;
int fd;
if (!have_identity)
ask_filename(pw, "Enter file in which the key is");
if (stat(identity_file, &st) < 0) {
perror(identity_file);
exit(1);
}
private = key_load_private(identity_file, "", &comment);
if (private == NULL) {
if (identity_passphrase)
passphrase = xstrdup(identity_passphrase);
else if (identity_new_passphrase)
passphrase = xstrdup(identity_new_passphrase);
else
passphrase = read_passphrase("Enter passphrase: ",
RP_ALLOW_STDIN);
/* Try to load using the passphrase. */
private = key_load_private(identity_file, passphrase, &comment);
if (private == NULL) {
memset(passphrase, 0, strlen(passphrase));
xfree(passphrase);
printf("Bad passphrase.\n");
exit(1);
}
} else {
passphrase = xstrdup("");
}
if (private->type != KEY_RSA1) {
fprintf(stderr, "Comments are only supported for RSA1 keys.\n");
key_free(private);
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));
key_free(private);
exit(1);
}
if (strchr(new_comment, '\n'))
*strchr(new_comment, '\n') = 0;
}
/* Save the file using the new passphrase. */
if (!key_save_private(private, identity_file, passphrase, new_comment)) {
printf("Saving the key failed: %s.\n", identity_file);
memset(passphrase, 0, strlen(passphrase));
xfree(passphrase);
key_free(private);
xfree(comment);
exit(1);
}
memset(passphrase, 0, strlen(passphrase));
xfree(passphrase);
public = key_from_private(private);
key_free(private);
strlcat(identity_file, ".pub", sizeof(identity_file));
fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
if (fd == -1) {
printf("Could not save your public key in %s\n", identity_file);
exit(1);
}
f = fdopen(fd, "w");
if (f == NULL) {
printf("fdopen %s failed", identity_file);
exit(1);
}
if (!key_write(public, f))
fprintf(stderr, "write key failed");
key_free(public);
fprintf(f, " %s\n", new_comment);
fclose(f);
xfree(comment);
printf("The comment in your key file has been changed.\n");
exit(0);
}
static void
usage(void)
{
fprintf(stderr, "Usage: %s [options]\n", __progname);
fprintf(stderr, "Options:\n");
fprintf(stderr, " -a trials Number of trials for screening DH-GEX moduli.\n");
fprintf(stderr, " -B Show bubblebabble digest of key file.\n");
fprintf(stderr, " -b bits Number of bits in the key to create.\n");
fprintf(stderr, " -C comment Provide new comment.\n");
fprintf(stderr, " -c Change comment in private and public key files.\n");
#ifdef SMARTCARD
fprintf(stderr, " -D reader Download public key from smartcard.\n");
#endif /* SMARTCARD */
fprintf(stderr, " -e Convert OpenSSH to RFC 4716 key file.\n");
fprintf(stderr, " -F hostname Find hostname in known hosts file.\n");
fprintf(stderr, " -f filename Filename of the key file.\n");
fprintf(stderr, " -G file Generate candidates for DH-GEX moduli.\n");
fprintf(stderr, " -g Use generic DNS resource record format.\n");
fprintf(stderr, " -H Hash names in known_hosts file.\n");
fprintf(stderr, " -i Convert RFC 4716 to OpenSSH key file.\n");
fprintf(stderr, " -l Show fingerprint of key file.\n");
fprintf(stderr, " -M memory Amount of memory (MB) to use for generating DH-GEX moduli.\n");
fprintf(stderr, " -N phrase Provide new passphrase.\n");
fprintf(stderr, " -P phrase Provide old passphrase.\n");
fprintf(stderr, " -p Change passphrase of private key file.\n");
fprintf(stderr, " -q Quiet.\n");
fprintf(stderr, " -R hostname Remove host from known_hosts file.\n");
fprintf(stderr, " -r hostname Print DNS resource record.\n");
fprintf(stderr, " -S start Start point (hex) for generating DH-GEX moduli.\n");
fprintf(stderr, " -T file Screen candidates for DH-GEX moduli.\n");
fprintf(stderr, " -t type Specify type of key to create.\n");
#ifdef SMARTCARD
fprintf(stderr, " -U reader Upload private key to smartcard.\n");
#endif /* SMARTCARD */
fprintf(stderr, " -v Verbose.\n");
fprintf(stderr, " -W gen Generator to use for generating DH-GEX moduli.\n");
fprintf(stderr, " -y Read private key file and print public key.\n");
exit(1);
}
/*
* Main program for key management.
*/
int
main(int argc, char **argv)
{
char dotsshdir[MAXPATHLEN], comment[1024], *passphrase1, *passphrase2;
char out_file[MAXPATHLEN], *reader_id = NULL;
char *rr_hostname = NULL;
Key *private, *public;
struct passwd *pw;
struct stat st;
int opt, type, fd, download = 0;
u_int32_t memory = 0, generator_wanted = 0, trials = 100;
int do_gen_candidates = 0, do_screen_candidates = 0;
int log_level = SYSLOG_LEVEL_INFO;
BIGNUM *start = NULL;
FILE *f;
const char *errstr;
extern int optind;
extern char *optarg;
/* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
sanitise_stdfd();
__progname = ssh_get_progname(argv[0]);
SSLeay_add_all_algorithms();
log_init(argv[0], SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_USER, 1);
init_rng();
seed_rng();
/* we need this for the home * directory. */
pw = getpwuid(getuid());
if (!pw) {
printf("You don't exist, go away!\n");
exit(1);
}
if (gethostname(hostname, sizeof(hostname)) < 0) {
perror("gethostname");
exit(1);
}
while ((opt = getopt(argc, argv,
"degiqpclBHvxXyF:b:f:t:U:D:P:N:C:r:g:R:T:G:M:S:a:W:")) != -1) {
switch (opt) {
case 'b':
bits = (u_int32_t)strtonum(optarg, 768, 32768, &errstr);
if (errstr)
fatal("Bits has bad value %s (%s)",
optarg, errstr);
break;
case 'F':
find_host = 1;
rr_hostname = optarg;
break;
case 'H':
hash_hosts = 1;
break;
case 'R':
delete_host = 1;
rr_hostname = optarg;
break;
case 'l':
print_fingerprint = 1;
break;
case 'B':
print_bubblebabble = 1;
break;
case 'p':
change_passphrase = 1;
break;
case 'c':
change_comment = 1;
break;
case 'f':
if (strlcpy(identity_file, optarg, sizeof(identity_file)) >=
sizeof(identity_file))
fatal("Identity filename too long");
have_identity = 1;
break;
case 'g':
print_generic = 1;
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 'e':
case 'x':
/* export key */
convert_to_ssh2 = 1;
break;
case 'i':
case 'X':
/* import key */
convert_from_ssh2 = 1;
break;
case 'y':
print_public = 1;
break;
case 'd':
key_type_name = "dsa";
break;
case 't':
key_type_name = optarg;
break;
case 'D':
download = 1;
/*FALLTHROUGH*/
case 'U':
reader_id = optarg;
break;
case 'v':
if (log_level == SYSLOG_LEVEL_INFO)
log_level = SYSLOG_LEVEL_DEBUG1;
else {
if (log_level >= SYSLOG_LEVEL_DEBUG1 &&
log_level < SYSLOG_LEVEL_DEBUG3)
log_level++;
}
break;
case 'r':
rr_hostname = optarg;
break;
case 'W':
generator_wanted = (u_int32_t)strtonum(optarg, 1,
UINT_MAX, &errstr);
if (errstr)
fatal("Desired generator has bad value: %s (%s)",
optarg, errstr);
break;
case 'a':
trials = (u_int32_t)strtonum(optarg, 1, UINT_MAX, &errstr);
if (errstr)
fatal("Invalid number of trials: %s (%s)",
optarg, errstr);
break;
case 'M':
memory = (u_int32_t)strtonum(optarg, 1, UINT_MAX, &errstr);
if (errstr) {
fatal("Memory limit is %s: %s", errstr, optarg);
}
break;
case 'G':
do_gen_candidates = 1;
if (strlcpy(out_file, optarg, sizeof(out_file)) >=
sizeof(out_file))
fatal("Output filename too long");
break;
case 'T':
do_screen_candidates = 1;
if (strlcpy(out_file, optarg, sizeof(out_file)) >=
sizeof(out_file))
fatal("Output filename too long");
break;
case 'S':
/* XXX - also compare length against bits */
if (BN_hex2bn(&start, optarg) == 0)
fatal("Invalid start point.");
break;
case '?':
default:
usage();
}
}
/* reinit */
log_init(argv[0], log_level, SYSLOG_FACILITY_USER, 1);
if (optind < argc) {
printf("Too many arguments.\n");
usage();
}
if (change_passphrase && change_comment) {
printf("Can only have one of -p and -c.\n");
usage();
}
if (delete_host || hash_hosts || find_host)
do_known_hosts(pw, rr_hostname);
if (print_fingerprint || print_bubblebabble)
do_fingerprint(pw);
if (change_passphrase)
do_change_passphrase(pw);
if (change_comment)
do_change_comment(pw);
if (convert_to_ssh2)
do_convert_to_ssh2(pw);
if (convert_from_ssh2)
do_convert_from_ssh2(pw);
if (print_public)
do_print_public(pw);
if (rr_hostname != NULL) {
unsigned int n = 0;
if (have_identity) {
n = do_print_resource_record(pw,
identity_file, rr_hostname);
if (n == 0) {
perror(identity_file);
exit(1);
}
exit(0);
} else {
n += do_print_resource_record(pw,
_PATH_HOST_RSA_KEY_FILE, rr_hostname);
n += do_print_resource_record(pw,
_PATH_HOST_DSA_KEY_FILE, rr_hostname);
if (n == 0)
fatal("no keys found.");
exit(0);
}
}
if (reader_id != NULL) {
#ifdef SMARTCARD
if (download)
do_download(pw, reader_id);
else
do_upload(pw, reader_id);
#else /* SMARTCARD */
fatal("no support for smartcards.");
#endif /* SMARTCARD */
}
if (do_gen_candidates) {
FILE *out = fopen(out_file, "w");
if (out == NULL) {
error("Couldn't open modulus candidate file \"%s\": %s",
out_file, strerror(errno));
return (1);
}
if (bits == 0)
bits = DEFAULT_BITS;
if (gen_candidates(out, memory, bits, start) != 0)
fatal("modulus candidate generation failed");
return (0);
}
if (do_screen_candidates) {
FILE *in;
FILE *out = fopen(out_file, "w");
if (have_identity && strcmp(identity_file, "-") != 0) {
if ((in = fopen(identity_file, "r")) == NULL) {
fatal("Couldn't open modulus candidate "
"file \"%s\": %s", identity_file,
strerror(errno));
}
} else
in = stdin;
if (out == NULL) {
fatal("Couldn't open moduli file \"%s\": %s",
out_file, strerror(errno));
}
if (prime_test(in, out, trials, generator_wanted) != 0)
fatal("modulus screening failed");
return (0);
}
arc4random_stir();
if (key_type_name == NULL)
key_type_name = "rsa";
type = key_type_from_name(key_type_name);
if (type == KEY_UNSPEC) {
fprintf(stderr, "unknown key type %s\n", key_type_name);
exit(1);
}
if (bits == 0)
bits = (type == KEY_DSA) ? DEFAULT_BITS_DSA : DEFAULT_BITS;
if (type == KEY_DSA && bits != 1024)
fatal("DSA keys must be 1024 bits");
if (!quiet)
printf("Generating public/private %s key pair.\n", key_type_name);
private = key_generate(type, bits);
if (private == NULL) {
fprintf(stderr, "key_generate failed");
exit(1);
}
public = key_from_private(private);
if (!have_identity)
ask_filename(pw, "Enter file in which to save the key");
/* Create ~/.ssh directory if it doesn't already exist. */
snprintf(dotsshdir, sizeof dotsshdir, "%s/%s", pw->pw_dir, _PATH_SSH_USER_DIR);
if (strstr(identity_file, dotsshdir) != NULL &&
stat(dotsshdir, &st) < 0) {
if (mkdir(dotsshdir, 0700) < 0)
error("Could not create directory '%s'.", dotsshdir);
else if (!quiet)
printf("Created directory '%s'.\n", dotsshdir);
}
/* If the file already exists, ask the user to confirm. */
if (stat(identity_file, &st) >= 0) {
char yesno[3];
printf("%s already exists.\n", identity_file);
printf("Overwrite (y/n)? ");
fflush(stdout);
if (fgets(yesno, sizeof(yesno), stdin) == NULL)
exit(1);
if (yesno[0] != 'y' && yesno[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): ", RP_ALLOW_STDIN);
passphrase2 = read_passphrase("Enter same passphrase again: ",
RP_ALLOW_STDIN);
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);
}
if (identity_comment) {
strlcpy(comment, identity_comment, sizeof(comment));
} else {
/* Create default commend field for the passphrase. */
snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
}
/* Save the key with the given passphrase and comment. */
if (!key_save_private(private, identity_file, passphrase1, comment)) {
printf("Saving the key failed: %s.\n", identity_file);
memset(passphrase1, 0, strlen(passphrase1));
xfree(passphrase1);
exit(1);
}
/* Clear the passphrase. */
memset(passphrase1, 0, strlen(passphrase1));
xfree(passphrase1);
/* Clear the private key and the random number generator. */
key_free(private);
arc4random_stir();
if (!quiet)
printf("Your identification has been saved in %s.\n", identity_file);
strlcat(identity_file, ".pub", sizeof(identity_file));
fd = open(identity_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
if (fd == -1) {
printf("Could not save your public key in %s\n", identity_file);
exit(1);
}
f = fdopen(fd, "w");
if (f == NULL) {
printf("fdopen %s failed", identity_file);
exit(1);
}
if (!key_write(public, f))
fprintf(stderr, "write key failed");
fprintf(f, " %s\n", comment);
fclose(f);
if (!quiet) {
char *fp = key_fingerprint(public, SSH_FP_MD5, SSH_FP_HEX);
printf("Your public key has been saved in %s.\n",
identity_file);
printf("The key fingerprint is:\n");
printf("%s %s\n", fp, comment);
xfree(fp);
}
key_free(public);
exit(0);
}