sshkey.h revision 1.1.1.17 1 /* $OpenBSD: sshkey.h,v 1.49 2021/01/26 00:49:30 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 *sshkey_new(int);
162 void sshkey_free(struct sshkey *);
163 int sshkey_equal_public(const struct sshkey *,
164 const struct sshkey *);
165 int sshkey_equal(const struct sshkey *, const struct sshkey *);
166 char *sshkey_fingerprint(const struct sshkey *,
167 int, enum sshkey_fp_rep);
168 int sshkey_fingerprint_raw(const struct sshkey *k,
169 int, u_char **retp, size_t *lenp);
170 const char *sshkey_type(const struct sshkey *);
171 const char *sshkey_cert_type(const struct sshkey *);
172 int sshkey_format_text(const struct sshkey *, struct sshbuf *);
173 int sshkey_write(const struct sshkey *, FILE *);
174 int sshkey_read(struct sshkey *, char **);
175 u_int sshkey_size(const struct sshkey *);
176
177 int sshkey_generate(int type, u_int bits, struct sshkey **keyp);
178 int sshkey_from_private(const struct sshkey *, struct sshkey **);
179
180 int sshkey_is_shielded(struct sshkey *);
181 int sshkey_shield_private(struct sshkey *);
182 int sshkey_unshield_private(struct sshkey *);
183
184 int sshkey_type_from_name(const char *);
185 int sshkey_is_cert(const struct sshkey *);
186 int sshkey_is_sk(const struct sshkey *);
187 int sshkey_type_is_cert(int);
188 int sshkey_type_plain(int);
189 int sshkey_to_certified(struct sshkey *);
190 int sshkey_drop_cert(struct sshkey *);
191 int sshkey_cert_copy(const struct sshkey *, struct sshkey *);
192 int sshkey_cert_check_authority(const struct sshkey *, int, int, int,
193 const char *, const char **);
194 int sshkey_cert_check_host(const struct sshkey *, const char *,
195 int , const char *, const char **);
196 size_t sshkey_format_cert_validity(const struct sshkey_cert *,
197 char *, size_t) __attribute__((__bounded__(__string__, 2, 3)));
198 int sshkey_check_cert_sigtype(const struct sshkey *, const char *);
199
200 int sshkey_certify(struct sshkey *, struct sshkey *,
201 const char *, const char *, const char *);
202 /* Variant allowing use of a custom signature function (e.g. for ssh-agent) */
203 typedef int sshkey_certify_signer(struct sshkey *, u_char **, size_t *,
204 const u_char *, size_t, const char *, const char *, const char *,
205 u_int, void *);
206 int sshkey_certify_custom(struct sshkey *, struct sshkey *, const char *,
207 const char *, const char *, sshkey_certify_signer *, void *);
208
209 int sshkey_ecdsa_nid_from_name(const char *);
210 int sshkey_curve_name_to_nid(const char *);
211 const char * sshkey_curve_nid_to_name(int);
212 u_int sshkey_curve_nid_to_bits(int);
213 int sshkey_ecdsa_bits_to_nid(int);
214 int sshkey_ecdsa_key_to_nid(EC_KEY *);
215 int sshkey_ec_nid_to_hash_alg(int nid);
216 int sshkey_ec_validate_public(const EC_GROUP *, const EC_POINT *);
217 int sshkey_ec_validate_private(const EC_KEY *);
218 const char *sshkey_ssh_name(const struct sshkey *);
219 const char *sshkey_ssh_name_plain(const struct sshkey *);
220 int sshkey_names_valid2(const char *, int);
221 char *sshkey_alg_list(int, int, int, char);
222
223 int sshkey_from_blob(const u_char *, size_t, struct sshkey **);
224 int sshkey_fromb(struct sshbuf *, struct sshkey **);
225 int sshkey_froms(struct sshbuf *, struct sshkey **);
226 int sshkey_to_blob(const struct sshkey *, u_char **, size_t *);
227 int sshkey_to_base64(const struct sshkey *, char **);
228 int sshkey_putb(const struct sshkey *, struct sshbuf *);
229 int sshkey_puts(const struct sshkey *, struct sshbuf *);
230 int sshkey_puts_opts(const struct sshkey *, struct sshbuf *,
231 enum sshkey_serialize_rep);
232 int sshkey_plain_to_blob(const struct sshkey *, u_char **, size_t *);
233 int sshkey_putb_plain(const struct sshkey *, struct sshbuf *);
234
235 int sshkey_sign(struct sshkey *, u_char **, size_t *,
236 const u_char *, size_t, const char *, const char *, const char *, u_int);
237 int sshkey_verify(const struct sshkey *, const u_char *, size_t,
238 const u_char *, size_t, const char *, u_int, struct sshkey_sig_details **);
239 int sshkey_check_sigtype(const u_char *, size_t, const char *);
240 const char *sshkey_sigalg_by_name(const char *);
241 int sshkey_get_sigtype(const u_char *, size_t, char **);
242
243 /* for debug */
244 void sshkey_dump_ec_point(const EC_GROUP *, const EC_POINT *);
245 void sshkey_dump_ec_key(const EC_KEY *);
246
247 /* private key parsing and serialisation */
248 int sshkey_private_serialize(struct sshkey *key, struct sshbuf *buf);
249 int sshkey_private_serialize_opt(struct sshkey *key, struct sshbuf *buf,
250 enum sshkey_serialize_rep);
251 int sshkey_private_deserialize(struct sshbuf *buf, struct sshkey **keyp);
252
253 /* private key file format parsing and serialisation */
254 int sshkey_private_to_fileblob(struct sshkey *key, struct sshbuf *blob,
255 const char *passphrase, const char *comment,
256 int format, const char *openssh_format_cipher, int openssh_format_rounds);
257 int sshkey_parse_private_fileblob(struct sshbuf *buffer,
258 const char *passphrase, struct sshkey **keyp, char **commentp);
259 int sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type,
260 const char *passphrase, struct sshkey **keyp, char **commentp);
261 int sshkey_parse_pubkey_from_private_fileblob_type(struct sshbuf *blob,
262 int type, struct sshkey **pubkeyp);
263
264 /* XXX should be internal, but used by ssh-keygen */
265 int ssh_rsa_complete_crt_parameters(struct sshkey *, const BIGNUM *);
266
267 /* stateful keys (e.g. XMSS) */
268 int sshkey_set_filename(struct sshkey *, const char *);
269 int sshkey_enable_maxsign(struct sshkey *, u_int32_t);
270 u_int32_t sshkey_signatures_left(const struct sshkey *);
271 int sshkey_forward_state(const struct sshkey *, u_int32_t, int);
272 int sshkey_private_serialize_maxsign(struct sshkey *key,
273 struct sshbuf *buf, u_int32_t maxsign, int);
274
275 void sshkey_sig_details_free(struct sshkey_sig_details *);
276
277 #ifdef SSHKEY_INTERNAL
278 int ssh_rsa_sign(const struct sshkey *key,
279 u_char **sigp, size_t *lenp, const u_char *data, size_t datalen,
280 const char *ident);
281 int ssh_rsa_verify(const struct sshkey *key,
282 const u_char *sig, size_t siglen, const u_char *data, size_t datalen,
283 const char *alg);
284 int ssh_dss_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
285 const u_char *data, size_t datalen, u_int compat);
286 int ssh_dss_verify(const struct sshkey *key,
287 const u_char *signature, size_t signaturelen,
288 const u_char *data, size_t datalen, u_int compat);
289 int ssh_ecdsa_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
290 const u_char *data, size_t datalen, u_int compat);
291 int ssh_ecdsa_verify(const struct sshkey *key,
292 const u_char *signature, size_t signaturelen,
293 const u_char *data, size_t datalen, u_int compat);
294 int ssh_ecdsa_sk_verify(const struct sshkey *key,
295 const u_char *signature, size_t signaturelen,
296 const u_char *data, size_t datalen, u_int compat,
297 struct sshkey_sig_details **detailsp);
298 int ssh_ed25519_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
299 const u_char *data, size_t datalen, u_int compat);
300 int ssh_ed25519_verify(const struct sshkey *key,
301 const u_char *signature, size_t signaturelen,
302 const u_char *data, size_t datalen, u_int compat);
303 int ssh_ed25519_sk_verify(const struct sshkey *key,
304 const u_char *signature, size_t signaturelen,
305 const u_char *data, size_t datalen, u_int compat,
306 struct sshkey_sig_details **detailsp);
307 int ssh_xmss_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
308 const u_char *data, size_t datalen, u_int compat);
309 int ssh_xmss_verify(const struct sshkey *key,
310 const u_char *signature, size_t signaturelen,
311 const u_char *data, size_t datalen, u_int compat);
312 #endif
313
314 #ifndef WITH_OPENSSL
315 #undef RSA
316 #undef DSA
317 #undef EC_KEY
318 #undef EC_GROUP
319 #undef EC_POINT
320 #endif /* WITH_OPENSSL */
321
322 #endif /* SSHKEY_H */
323