1 /* $OpenBSD: authfile.c,v 1.140 2020/04/17 07:15:11 djm Exp $ */
3 * Copyright (c) 2000, 2013 Markus Friedl. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 #include <sys/types.h>
52 #define MAX_KEY_FILE_SIZE (1024 * 1024)
54 /* Save a key blob to a file */
56 sshkey_save_private_blob(struct sshbuf *keybuf, const char *filename)
62 r = sshbuf_write_file(filename, keybuf);
68 sshkey_save_private(struct sshkey *key, const char *filename,
69 const char *passphrase, const char *comment,
70 int format, const char *openssh_format_cipher, int openssh_format_rounds)
72 struct sshbuf *keyblob = NULL;
75 if ((keyblob = sshbuf_new()) == NULL)
76 return SSH_ERR_ALLOC_FAIL;
77 if ((r = sshkey_private_to_fileblob(key, keyblob, passphrase, comment,
78 format, openssh_format_cipher, openssh_format_rounds)) != 0)
80 if ((r = sshkey_save_private_blob(keyblob, filename)) != 0)
88 /* XXX remove error() calls from here? */
90 sshkey_perm_ok(int fd, const char *filename)
94 if (fstat(fd, &st) == -1)
95 return SSH_ERR_SYSTEM_ERROR;
97 * if a key owned by the user is accessed, then we check the
98 * permissions of the file. if the key owned by a different user,
102 if (check_ntsec(filename))
104 if ((st.st_uid == getuid()) && (st.st_mode & 077) != 0) {
105 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
106 error("@ WARNING: UNPROTECTED PRIVATE KEY FILE! @");
107 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
108 error("Permissions 0%3.3o for '%s' are too open.",
109 (u_int)st.st_mode & 0777, filename);
110 error("It is required that your private key files are NOT accessible by others.");
111 error("This private key will be ignored.");
112 return SSH_ERR_KEY_BAD_PERMISSIONS;
118 sshkey_load_private_type(int type, const char *filename, const char *passphrase,
119 struct sshkey **keyp, char **commentp)
125 if (commentp != NULL)
128 if ((fd = open(filename, O_RDONLY)) == -1)
129 return SSH_ERR_SYSTEM_ERROR;
131 r = sshkey_perm_ok(fd, filename);
135 r = sshkey_load_private_type_fd(fd, type, passphrase, keyp, commentp);
136 if (r == 0 && keyp && *keyp)
137 r = sshkey_set_filename(*keyp, filename);
144 sshkey_load_private(const char *filename, const char *passphrase,
145 struct sshkey **keyp, char **commentp)
147 return sshkey_load_private_type(KEY_UNSPEC, filename, passphrase,
152 sshkey_load_private_type_fd(int fd, int type, const char *passphrase,
153 struct sshkey **keyp, char **commentp)
155 struct sshbuf *buffer = NULL;
160 if ((r = sshbuf_load_fd(fd, &buffer)) != 0 ||
161 (r = sshkey_parse_private_fileblob_type(buffer, type,
162 passphrase, keyp, commentp)) != 0)
172 /* Load a pubkey from the unencrypted envelope of a new-format private key */
174 sshkey_load_pubkey_from_private(const char *filename, struct sshkey **pubkeyp)
176 struct sshbuf *buffer = NULL;
177 struct sshkey *pubkey = NULL;
183 if ((fd = open(filename, O_RDONLY)) == -1)
184 return SSH_ERR_SYSTEM_ERROR;
185 if ((r = sshbuf_load_fd(fd, &buffer)) != 0 ||
186 (r = sshkey_parse_pubkey_from_private_fileblob_type(buffer,
187 KEY_UNSPEC, &pubkey)) != 0)
189 if ((r = sshkey_set_filename(pubkey, filename)) != 0)
192 if (pubkeyp != NULL) {
205 sshkey_try_load_public(struct sshkey **kp, const char *filename,
209 char *line = NULL, *cp;
212 struct sshkey *k = NULL;
215 if (commentp != NULL)
217 if ((f = fopen(filename, "r")) == NULL)
218 return SSH_ERR_SYSTEM_ERROR;
219 if ((k = sshkey_new(KEY_UNSPEC)) == NULL) {
221 return SSH_ERR_ALLOC_FAIL;
223 while (getline(&line, &linesize, f) != -1) {
231 /* Abort loading if this looks like a private key */
232 if (strncmp(cp, "-----BEGIN", 10) == 0 ||
233 strcmp(cp, "SSH PRIVATE KEY FILE") == 0)
235 /* Skip leading whitespace. */
236 for (; *cp && (*cp == ' ' || *cp == '\t'); cp++)
239 if ((r = sshkey_read(k, &cp)) == 0) {
240 cp[strcspn(cp, "\r\n")] = '\0';
242 *commentp = strdup(*cp ?
244 if (*commentp == NULL)
245 r = SSH_ERR_ALLOC_FAIL;
258 return SSH_ERR_INVALID_FORMAT;
261 /* load public key from any pubkey file */
263 sshkey_load_public(const char *filename, struct sshkey **keyp, char **commentp)
265 char *pubfile = NULL;
270 if (commentp != NULL)
273 if ((r = sshkey_try_load_public(keyp, filename, commentp)) == 0)
276 /* try .pub suffix */
277 if (asprintf(&pubfile, "%s.pub", filename) == -1)
278 return SSH_ERR_ALLOC_FAIL;
279 if ((r = sshkey_try_load_public(keyp, pubfile, commentp)) == 0)
282 /* finally, try to extract public key from private key file */
283 if ((r = sshkey_load_pubkey_from_private(filename, keyp)) == 0)
291 /* Load the certificate associated with the named private key */
293 sshkey_load_cert(const char *filename, struct sshkey **keyp)
295 struct sshkey *pub = NULL;
297 int r = SSH_ERR_INTERNAL_ERROR;
302 if (asprintf(&file, "%s-cert.pub", filename) == -1)
303 return SSH_ERR_ALLOC_FAIL;
305 r = sshkey_try_load_public(keyp, file, NULL);
311 /* Load private key and certificate */
313 sshkey_load_private_cert(int type, const char *filename, const char *passphrase,
314 struct sshkey **keyp)
316 struct sshkey *key = NULL, *cert = NULL;
327 #endif /* WITH_OPENSSL */
333 return SSH_ERR_KEY_TYPE_UNKNOWN;
336 if ((r = sshkey_load_private_type(type, filename,
337 passphrase, &key, NULL)) != 0 ||
338 (r = sshkey_load_cert(filename, &cert)) != 0)
341 /* Make sure the private key matches the certificate */
342 if (sshkey_equal_public(key, cert) == 0) {
343 r = SSH_ERR_KEY_CERT_MISMATCH;
347 if ((r = sshkey_to_certified(key)) != 0 ||
348 (r = sshkey_cert_copy(cert, key)) != 0)
362 * Returns success if the specified "key" is listed in the file "filename",
363 * SSH_ERR_KEY_NOT_FOUND: if the key is not listed or another error.
364 * If "strict_type" is set then the key type must match exactly,
365 * otherwise a comparison that ignores certficiate data is performed.
366 * If "check_ca" is set and "key" is a certificate, then its CA key is
367 * also checked and sshkey_in_file() will return success if either is found.
370 sshkey_in_file(struct sshkey *key, const char *filename, int strict_type,
374 char *line = NULL, *cp;
377 struct sshkey *pub = NULL;
379 int (*sshkey_compare)(const struct sshkey *, const struct sshkey *) =
380 strict_type ? sshkey_equal : sshkey_equal_public;
382 if ((f = fopen(filename, "r")) == NULL)
383 return SSH_ERR_SYSTEM_ERROR;
385 while (getline(&line, &linesize, f) != -1) {
390 /* Skip leading whitespace. */
391 for (; *cp && (*cp == ' ' || *cp == '\t'); cp++)
394 /* Skip comments and empty lines */
402 if ((pub = sshkey_new(KEY_UNSPEC)) == NULL) {
403 r = SSH_ERR_ALLOC_FAIL;
406 switch (r = sshkey_read(pub, &cp)) {
409 case SSH_ERR_KEY_LENGTH:
414 if (sshkey_compare(key, pub) ||
415 (check_ca && sshkey_is_cert(key) &&
416 sshkey_compare(key->cert->signature_key, pub))) {
421 r = SSH_ERR_KEY_NOT_FOUND;
430 * Checks whether the specified key is revoked, returning 0 if not,
431 * SSH_ERR_KEY_REVOKED if it is or another error code if something
432 * unexpected happened.
433 * This will check both the key and, if it is a certificate, its CA key too.
434 * "revoked_keys_file" may be a KRL or a one-per-line list of public keys.
437 sshkey_check_revoked(struct sshkey *key, const char *revoked_keys_file)
441 r = ssh_krl_file_contains_key(revoked_keys_file, key);
442 /* If this was not a KRL to begin with then continue below */
443 if (r != SSH_ERR_KRL_BAD_MAGIC)
447 * If the file is not a KRL or we can't handle KRLs then attempt to
448 * parse the file as a flat list of keys.
450 switch ((r = sshkey_in_file(key, revoked_keys_file, 0, 1))) {
452 /* Key found => revoked */
453 return SSH_ERR_KEY_REVOKED;
454 case SSH_ERR_KEY_NOT_FOUND:
455 /* Key not found => not revoked */
458 /* Some other error occurred */
464 * Advanced *cpp past the end of key options, defined as the first unquoted
465 * whitespace character. Returns 0 on success or -1 on failure (e.g.
466 * unterminated quotes).
469 sshkey_advance_past_options(char **cpp)
474 for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
475 if (*cp == '\\' && cp[1] == '"')
476 cp++; /* Skip both */
481 /* return failure for unterminated quotes */
482 return (*cp == '\0' && quoted) ? -1 : 0;
485 /* Save a public key */
487 sshkey_save_public(const struct sshkey *key, const char *path,
492 int r = SSH_ERR_INTERNAL_ERROR;
494 if ((fd = open(path, O_WRONLY|O_CREAT|O_TRUNC, 0644)) == -1)
495 return SSH_ERR_SYSTEM_ERROR;
496 if ((f = fdopen(fd, "w")) == NULL) {
497 r = SSH_ERR_SYSTEM_ERROR;
500 if ((r = sshkey_write(key, f)) != 0)
502 fprintf(f, " %s\n", comment);
503 if (ferror(f) || fclose(f) != 0) {
504 r = SSH_ERR_SYSTEM_ERROR;