sshkey.h revision 1.1.1.22 1 /* $OpenBSD: sshkey.h,v 1.62 2023/06/21 05:10:26 djm Exp $ */
2
3 /*
4 * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26 #ifndef SSHKEY_H
27 #define SSHKEY_H
28
29 #include <sys/types.h>
30
31 #ifdef WITH_OPENSSL
32 #include <openssl/rsa.h>
33 #include <openssl/dsa.h>
34 #include <openssl/ec.h>
35 #include <openssl/ecdsa.h>
36 #define SSH_OPENSSL_VERSION OpenSSL_version(OPENSSL_VERSION)
37 #else /* OPENSSL */
38 #define BIGNUM void
39 #define RSA void
40 #define DSA void
41 #define EC_KEY void
42 #define EC_GROUP void
43 #define EC_POINT void
44 #define SSH_OPENSSL_VERSION "without OpenSSL"
45 #endif /* WITH_OPENSSL */
46
47 #define SSH_RSA_MINIMUM_MODULUS_SIZE 1024
48 #define SSH_KEY_MAX_SIGN_DATA_SIZE (1 << 20)
49
50 struct sshbuf;
51
52 /* Key types */
53 enum sshkey_types {
54 KEY_RSA,
55 KEY_DSA,
56 KEY_ECDSA,
57 KEY_ED25519,
58 KEY_RSA_CERT,
59 KEY_DSA_CERT,
60 KEY_ECDSA_CERT,
61 KEY_ED25519_CERT,
62 KEY_XMSS,
63 KEY_XMSS_CERT,
64 KEY_ECDSA_SK,
65 KEY_ECDSA_SK_CERT,
66 KEY_ED25519_SK,
67 KEY_ED25519_SK_CERT,
68 KEY_UNSPEC
69 };
70
71 /* Default fingerprint hash */
72 #define SSH_FP_HASH_DEFAULT SSH_DIGEST_SHA256
73
74 /* Fingerprint representation formats */
75 enum sshkey_fp_rep {
76 SSH_FP_DEFAULT = 0,
77 SSH_FP_HEX,
78 SSH_FP_BASE64,
79 SSH_FP_BUBBLEBABBLE,
80 SSH_FP_RANDOMART
81 };
82
83 /* Private key serialisation formats, used on the wire */
84 enum sshkey_serialize_rep {
85 SSHKEY_SERIALIZE_DEFAULT = 0,
86 SSHKEY_SERIALIZE_STATE = 1, /* only state is serialized */
87 SSHKEY_SERIALIZE_FULL = 2, /* include keys for saving to disk */
88 SSHKEY_SERIALIZE_SHIELD = 3, /* everything, for encrypting in ram */
89 SSHKEY_SERIALIZE_INFO = 254, /* minimal information */
90 };
91
92 /* Private key disk formats */
93 enum sshkey_private_format {
94 SSHKEY_PRIVATE_OPENSSH = 0,
95 SSHKEY_PRIVATE_PEM = 1,
96 SSHKEY_PRIVATE_PKCS8 = 2,
97 };
98
99 /* key is stored in external hardware */
100 #define SSHKEY_FLAG_EXT 0x0001
101
102 #define SSHKEY_CERT_MAX_PRINCIPALS 256
103 /* XXX opaquify? */
104 struct sshkey_cert {
105 struct sshbuf *certblob; /* Kept around for use on wire */
106 u_int type; /* SSH2_CERT_TYPE_USER or SSH2_CERT_TYPE_HOST */
107 u_int64_t serial;
108 char *key_id;
109 u_int nprincipals;
110 char **principals;
111 u_int64_t valid_after, valid_before;
112 struct sshbuf *critical;
113 struct sshbuf *extensions;
114 struct sshkey *signature_key;
115 char *signature_type;
116 };
117
118 /* XXX opaquify? */
119 struct sshkey {
120 int type;
121 int flags;
122 /* KEY_RSA */
123 RSA *rsa;
124 /* KEY_DSA */
125 DSA *dsa;
126 /* KEY_ECDSA and KEY_ECDSA_SK */
127 int ecdsa_nid; /* NID of curve */
128 EC_KEY *ecdsa;
129 /* KEY_ED25519 and KEY_ED25519_SK */
130 u_char *ed25519_sk;
131 u_char *ed25519_pk;
132 /* KEY_XMSS */
133 char *xmss_name;
134 char *xmss_filename; /* for state file updates */
135 void *xmss_state; /* depends on xmss_name, opaque */
136 u_char *xmss_sk;
137 u_char *xmss_pk;
138 /* KEY_ECDSA_SK and KEY_ED25519_SK */
139 char *sk_application;
140 uint8_t sk_flags;
141 struct sshbuf *sk_key_handle;
142 struct sshbuf *sk_reserved;
143 /* Certificates */
144 struct sshkey_cert *cert;
145 /* Private key shielding */
146 u_char *shielded_private;
147 size_t shielded_len;
148 u_char *shield_prekey;
149 size_t shield_prekey_len;
150 };
151
152 #define ED25519_SK_SZ crypto_sign_ed25519_SECRETKEYBYTES
153 #define ED25519_PK_SZ crypto_sign_ed25519_PUBLICKEYBYTES
154
155 /* Additional fields contained in signature */
156 struct sshkey_sig_details {
157 uint32_t sk_counter; /* U2F signature counter */
158 uint8_t sk_flags; /* U2F signature flags; see ssh-sk.h */
159 };
160
161 struct sshkey_impl_funcs {
162 u_int (*size)(const struct sshkey *); /* optional */
163 int (*alloc)(struct sshkey *); /* optional */
164 void (*cleanup)(struct sshkey *); /* optional */
165 int (*equal)(const struct sshkey *, const struct sshkey *);
166 int (*serialize_public)(const struct sshkey *, struct sshbuf *,
167 enum sshkey_serialize_rep);
168 int (*deserialize_public)(const char *, struct sshbuf *,
169 struct sshkey *);
170 int (*serialize_private)(const struct sshkey *, struct sshbuf *,
171 enum sshkey_serialize_rep);
172 int (*deserialize_private)(const char *, struct sshbuf *,
173 struct sshkey *);
174 int (*generate)(struct sshkey *, int); /* optional */
175 int (*copy_public)(const struct sshkey *, struct sshkey *);
176 int (*sign)(struct sshkey *, u_char **, size_t *,
177 const u_char *, size_t, const char *,
178 const char *, const char *, u_int); /* optional */
179 int (*verify)(const struct sshkey *, const u_char *, size_t,
180 const u_char *, size_t, const char *, u_int,
181 struct sshkey_sig_details **);
182 };
183
184 struct sshkey_impl {
185 const char *name;
186 const char *shortname;
187 const char *sigalg;
188 int type;
189 int nid;
190 int cert;
191 int sigonly;
192 int keybits;
193 const struct sshkey_impl_funcs *funcs;
194 };
195
196 struct sshkey *sshkey_new(int);
197 void sshkey_free(struct sshkey *);
198 int sshkey_equal_public(const struct sshkey *,
199 const struct sshkey *);
200 int sshkey_equal(const struct sshkey *, const struct sshkey *);
201 char *sshkey_fingerprint(const struct sshkey *,
202 int, enum sshkey_fp_rep);
203 int sshkey_fingerprint_raw(const struct sshkey *k,
204 int, u_char **retp, size_t *lenp);
205 const char *sshkey_type(const struct sshkey *);
206 const char *sshkey_cert_type(const struct sshkey *);
207 int sshkey_format_text(const struct sshkey *, struct sshbuf *);
208 int sshkey_write(const struct sshkey *, FILE *);
209 int sshkey_read(struct sshkey *, char **);
210 u_int sshkey_size(const struct sshkey *);
211
212 int sshkey_generate(int type, u_int bits, struct sshkey **keyp);
213 int sshkey_from_private(const struct sshkey *, struct sshkey **);
214
215 int sshkey_is_shielded(struct sshkey *);
216 int sshkey_shield_private(struct sshkey *);
217 int sshkey_unshield_private(struct sshkey *);
218
219 int sshkey_type_from_name(const char *);
220 int sshkey_is_cert(const struct sshkey *);
221 int sshkey_is_sk(const struct sshkey *);
222 int sshkey_type_is_cert(int);
223 int sshkey_type_plain(int);
224
225 /* Returns non-zero if key name match sigalgs pattern list. (handles RSA) */
226 int sshkey_match_keyname_to_sigalgs(const char *, const char *);
227
228 int sshkey_to_certified(struct sshkey *);
229 int sshkey_drop_cert(struct sshkey *);
230 int sshkey_cert_copy(const struct sshkey *, struct sshkey *);
231 int sshkey_cert_check_authority(const struct sshkey *, int, int, int,
232 uint64_t, const char *, const char **);
233 int sshkey_cert_check_authority_now(const struct sshkey *, int, int, int,
234 const char *, const char **);
235 int sshkey_cert_check_host(const struct sshkey *, const char *,
236 int , const char *, const char **);
237 size_t sshkey_format_cert_validity(const struct sshkey_cert *,
238 char *, size_t) __attribute__((__bounded__(__string__, 2, 3)));
239 int sshkey_check_cert_sigtype(const struct sshkey *, const char *);
240
241 int sshkey_certify(struct sshkey *, struct sshkey *,
242 const char *, const char *, const char *);
243 /* Variant allowing use of a custom signature function (e.g. for ssh-agent) */
244 typedef int sshkey_certify_signer(struct sshkey *, u_char **, size_t *,
245 const u_char *, size_t, const char *, const char *, const char *,
246 u_int, void *);
247 int sshkey_certify_custom(struct sshkey *, struct sshkey *, const char *,
248 const char *, const char *, sshkey_certify_signer *, void *);
249
250 int sshkey_ecdsa_nid_from_name(const char *);
251 int sshkey_curve_name_to_nid(const char *);
252 const char * sshkey_curve_nid_to_name(int);
253 u_int sshkey_curve_nid_to_bits(int);
254 int sshkey_ecdsa_bits_to_nid(int);
255 int sshkey_ecdsa_key_to_nid(EC_KEY *);
256 int sshkey_ec_nid_to_hash_alg(int nid);
257 int sshkey_ec_validate_public(const EC_GROUP *, const EC_POINT *);
258 int sshkey_ec_validate_private(const EC_KEY *);
259 const char *sshkey_ssh_name(const struct sshkey *);
260 const char *sshkey_ssh_name_plain(const struct sshkey *);
261 int sshkey_names_valid2(const char *, int, int);
262 char *sshkey_alg_list(int, int, int, char);
263
264 int sshkey_from_blob(const u_char *, size_t, struct sshkey **);
265 int sshkey_fromb(struct sshbuf *, struct sshkey **);
266 int sshkey_froms(struct sshbuf *, struct sshkey **);
267 int sshkey_to_blob(const struct sshkey *, u_char **, size_t *);
268 int sshkey_to_base64(const struct sshkey *, char **);
269 int sshkey_putb(const struct sshkey *, struct sshbuf *);
270 int sshkey_puts(const struct sshkey *, struct sshbuf *);
271 int sshkey_puts_opts(const struct sshkey *, struct sshbuf *,
272 enum sshkey_serialize_rep);
273 int sshkey_plain_to_blob(const struct sshkey *, u_char **, size_t *);
274 int sshkey_putb_plain(const struct sshkey *, struct sshbuf *);
275
276 int sshkey_sign(struct sshkey *, u_char **, size_t *,
277 const u_char *, size_t, const char *, const char *, const char *, u_int);
278 int sshkey_verify(const struct sshkey *, const u_char *, size_t,
279 const u_char *, size_t, const char *, u_int, struct sshkey_sig_details **);
280 int sshkey_check_sigtype(const u_char *, size_t, const char *);
281 const char *sshkey_sigalg_by_name(const char *);
282 int sshkey_get_sigtype(const u_char *, size_t, char **);
283
284 /* for debug */
285 void sshkey_dump_ec_point(const EC_GROUP *, const EC_POINT *);
286 void sshkey_dump_ec_key(const EC_KEY *);
287
288 /* private key parsing and serialisation */
289 int sshkey_private_serialize(struct sshkey *key, struct sshbuf *buf);
290 int sshkey_private_serialize_opt(struct sshkey *key, struct sshbuf *buf,
291 enum sshkey_serialize_rep);
292 int sshkey_private_deserialize(struct sshbuf *buf, struct sshkey **keyp);
293
294 /* private key file format parsing and serialisation */
295 int sshkey_private_to_fileblob(struct sshkey *key, struct sshbuf *blob,
296 const char *passphrase, const char *comment,
297 int format, const char *openssh_format_cipher, int openssh_format_rounds);
298 int sshkey_parse_private_fileblob(struct sshbuf *buffer,
299 const char *passphrase, struct sshkey **keyp, char **commentp);
300 int sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type,
301 const char *passphrase, struct sshkey **keyp, char **commentp);
302 int sshkey_parse_pubkey_from_private_fileblob_type(struct sshbuf *blob,
303 int type, struct sshkey **pubkeyp);
304
305 int sshkey_check_rsa_length(const struct sshkey *, int);
306 /* XXX should be internal, but used by ssh-keygen */
307 int ssh_rsa_complete_crt_parameters(struct sshkey *, const BIGNUM *);
308
309 /* stateful keys (e.g. XMSS) */
310 int sshkey_set_filename(struct sshkey *, const char *);
311 int sshkey_enable_maxsign(struct sshkey *, u_int32_t);
312 u_int32_t sshkey_signatures_left(const struct sshkey *);
313 int sshkey_forward_state(const struct sshkey *, u_int32_t, int);
314 int sshkey_private_serialize_maxsign(struct sshkey *key,
315 struct sshbuf *buf, u_int32_t maxsign, int);
316
317 void sshkey_sig_details_free(struct sshkey_sig_details *);
318
319 #ifdef SSHKEY_INTERNAL
320 int sshkey_sk_fields_equal(const struct sshkey *a, const struct sshkey *b);
321 void sshkey_sk_cleanup(struct sshkey *k);
322 int sshkey_serialize_sk(const struct sshkey *key, struct sshbuf *b);
323 int sshkey_copy_public_sk(const struct sshkey *from, struct sshkey *to);
324 int sshkey_deserialize_sk(struct sshbuf *b, struct sshkey *key);
325 int sshkey_serialize_private_sk(const struct sshkey *key,
326 struct sshbuf *buf);
327 int sshkey_private_deserialize_sk(struct sshbuf *buf, struct sshkey *k);
328 #ifdef WITH_OPENSSL
329 int check_rsa_length(const RSA *rsa); /* XXX remove */
330 #endif
331 #endif
332
333 #ifndef WITH_OPENSSL
334 #undef RSA
335 #undef DSA
336 #undef EC_KEY
337 #undef EC_GROUP
338 #undef EC_POINT
339 #endif /* WITH_OPENSSL */
340
341 #endif /* SSHKEY_H */
342