sshkey.h revision 1.1.1.16 1 /* $OpenBSD: sshkey.h,v 1.46 2020/08/27 01:06:19 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 #else /* OPENSSL */
37 #define BIGNUM void
38 #define RSA void
39 #define DSA void
40 #define EC_KEY void
41 #define EC_GROUP void
42 #define EC_POINT void
43 #endif /* WITH_OPENSSL */
44
45 #define SSH_RSA_MINIMUM_MODULUS_SIZE 1024
46 #define SSH_KEY_MAX_SIGN_DATA_SIZE (1 << 20)
47
48 struct sshbuf;
49
50 /* Key types */
51 enum sshkey_types {
52 KEY_RSA,
53 KEY_DSA,
54 KEY_ECDSA,
55 KEY_ED25519,
56 KEY_RSA_CERT,
57 KEY_DSA_CERT,
58 KEY_ECDSA_CERT,
59 KEY_ED25519_CERT,
60 KEY_XMSS,
61 KEY_XMSS_CERT,
62 KEY_ECDSA_SK,
63 KEY_ECDSA_SK_CERT,
64 KEY_ED25519_SK,
65 KEY_ED25519_SK_CERT,
66 KEY_UNSPEC
67 };
68
69 /* Default fingerprint hash */
70 #define SSH_FP_HASH_DEFAULT SSH_DIGEST_SHA256
71
72 /* Fingerprint representation formats */
73 enum sshkey_fp_rep {
74 SSH_FP_DEFAULT = 0,
75 SSH_FP_HEX,
76 SSH_FP_BASE64,
77 SSH_FP_BUBBLEBABBLE,
78 SSH_FP_RANDOMART
79 };
80
81 /* Private key serialisation formats, used on the wire */
82 enum sshkey_serialize_rep {
83 SSHKEY_SERIALIZE_DEFAULT = 0,
84 SSHKEY_SERIALIZE_STATE = 1, /* only state is serialized */
85 SSHKEY_SERIALIZE_FULL = 2, /* include keys for saving to disk */
86 SSHKEY_SERIALIZE_SHIELD = 3, /* everything, for encrypting in ram */
87 SSHKEY_SERIALIZE_INFO = 254, /* minimal information */
88 };
89
90 /* Private key disk formats */
91 enum sshkey_private_format {
92 SSHKEY_PRIVATE_OPENSSH = 0,
93 SSHKEY_PRIVATE_PEM = 1,
94 SSHKEY_PRIVATE_PKCS8 = 2,
95 };
96
97 /* key is stored in external hardware */
98 #define SSHKEY_FLAG_EXT 0x0001
99
100 #define SSHKEY_CERT_MAX_PRINCIPALS 256
101 /* XXX opaquify? */
102 struct sshkey_cert {
103 struct sshbuf *certblob; /* Kept around for use on wire */
104 u_int type; /* SSH2_CERT_TYPE_USER or SSH2_CERT_TYPE_HOST */
105 u_int64_t serial;
106 char *key_id;
107 u_int nprincipals;
108 char **principals;
109 u_int64_t valid_after, valid_before;
110 struct sshbuf *critical;
111 struct sshbuf *extensions;
112 struct sshkey *signature_key;
113 char *signature_type;
114 };
115
116 /* XXX opaquify? */
117 struct sshkey {
118 int type;
119 int flags;
120 /* KEY_RSA */
121 RSA *rsa;
122 /* KEY_DSA */
123 DSA *dsa;
124 /* KEY_ECDSA and KEY_ECDSA_SK */
125 int ecdsa_nid; /* NID of curve */
126 EC_KEY *ecdsa;
127 /* KEY_ED25519 and KEY_ED25519_SK */
128 u_char *ed25519_sk;
129 u_char *ed25519_pk;
130 /* KEY_XMSS */
131 char *xmss_name;
132 char *xmss_filename; /* for state file updates */
133 void *xmss_state; /* depends on xmss_name, opaque */
134 u_char *xmss_sk;
135 u_char *xmss_pk;
136 /* KEY_ECDSA_SK and KEY_ED25519_SK */
137 char *sk_application;
138 uint8_t sk_flags;
139 struct sshbuf *sk_key_handle;
140 struct sshbuf *sk_reserved;
141 /* Certificates */
142 struct sshkey_cert *cert;
143 /* Private key shielding */
144 u_char *shielded_private;
145 size_t shielded_len;
146 u_char *shield_prekey;
147 size_t shield_prekey_len;
148 };
149
150 #define ED25519_SK_SZ crypto_sign_ed25519_SECRETKEYBYTES
151 #define ED25519_PK_SZ crypto_sign_ed25519_PUBLICKEYBYTES
152
153 /* Additional fields contained in signature */
154 struct sshkey_sig_details {
155 uint32_t sk_counter; /* U2F signature counter */
156 uint8_t sk_flags; /* U2F signature flags; see ssh-sk.h */
157 };
158
159 struct sshkey *sshkey_new(int);
160 void sshkey_free(struct sshkey *);
161 int sshkey_equal_public(const struct sshkey *,
162 const struct sshkey *);
163 int sshkey_equal(const struct sshkey *, const struct sshkey *);
164 char *sshkey_fingerprint(const struct sshkey *,
165 int, enum sshkey_fp_rep);
166 int sshkey_fingerprint_raw(const struct sshkey *k,
167 int, u_char **retp, size_t *lenp);
168 const char *sshkey_type(const struct sshkey *);
169 const char *sshkey_cert_type(const struct sshkey *);
170 int sshkey_format_text(const struct sshkey *, struct sshbuf *);
171 int sshkey_write(const struct sshkey *, FILE *);
172 int sshkey_read(struct sshkey *, char **);
173 u_int sshkey_size(const struct sshkey *);
174
175 int sshkey_generate(int type, u_int bits, struct sshkey **keyp);
176 int sshkey_from_private(const struct sshkey *, struct sshkey **);
177
178 int sshkey_is_shielded(struct sshkey *);
179 int sshkey_shield_private(struct sshkey *);
180 int sshkey_unshield_private(struct sshkey *);
181
182 int sshkey_type_from_name(const char *);
183 int sshkey_is_cert(const struct sshkey *);
184 int sshkey_is_sk(const struct sshkey *);
185 int sshkey_type_is_cert(int);
186 int sshkey_type_plain(int);
187 int sshkey_to_certified(struct sshkey *);
188 int sshkey_drop_cert(struct sshkey *);
189 int sshkey_cert_copy(const struct sshkey *, struct sshkey *);
190 int sshkey_cert_check_authority(const struct sshkey *, int, int,
191 const char *, const char **);
192 size_t sshkey_format_cert_validity(const struct sshkey_cert *,
193 char *, size_t) __attribute__((__bounded__(__string__, 2, 3)));
194 int sshkey_check_cert_sigtype(const struct sshkey *, const char *);
195
196 int sshkey_certify(struct sshkey *, struct sshkey *,
197 const char *, const char *, const char *);
198 /* Variant allowing use of a custom signature function (e.g. for ssh-agent) */
199 typedef int sshkey_certify_signer(struct sshkey *, u_char **, size_t *,
200 const u_char *, size_t, const char *, const char *, const char *,
201 u_int, void *);
202 int sshkey_certify_custom(struct sshkey *, struct sshkey *, const char *,
203 const char *, const char *, sshkey_certify_signer *, void *);
204
205 int sshkey_ecdsa_nid_from_name(const char *);
206 int sshkey_curve_name_to_nid(const char *);
207 const char * sshkey_curve_nid_to_name(int);
208 u_int sshkey_curve_nid_to_bits(int);
209 int sshkey_ecdsa_bits_to_nid(int);
210 int sshkey_ecdsa_key_to_nid(EC_KEY *);
211 int sshkey_ec_nid_to_hash_alg(int nid);
212 int sshkey_ec_validate_public(const EC_GROUP *, const EC_POINT *);
213 int sshkey_ec_validate_private(const EC_KEY *);
214 const char *sshkey_ssh_name(const struct sshkey *);
215 const char *sshkey_ssh_name_plain(const struct sshkey *);
216 int sshkey_names_valid2(const char *, int);
217 char *sshkey_alg_list(int, int, int, char);
218
219 int sshkey_from_blob(const u_char *, size_t, struct sshkey **);
220 int sshkey_fromb(struct sshbuf *, struct sshkey **);
221 int sshkey_froms(struct sshbuf *, struct sshkey **);
222 int sshkey_to_blob(const struct sshkey *, u_char **, size_t *);
223 int sshkey_to_base64(const struct sshkey *, char **);
224 int sshkey_putb(const struct sshkey *, struct sshbuf *);
225 int sshkey_puts(const struct sshkey *, struct sshbuf *);
226 int sshkey_puts_opts(const struct sshkey *, struct sshbuf *,
227 enum sshkey_serialize_rep);
228 int sshkey_plain_to_blob(const struct sshkey *, u_char **, size_t *);
229 int sshkey_putb_plain(const struct sshkey *, struct sshbuf *);
230
231 int sshkey_sign(struct sshkey *, u_char **, size_t *,
232 const u_char *, size_t, const char *, const char *, const char *, u_int);
233 int sshkey_verify(const struct sshkey *, const u_char *, size_t,
234 const u_char *, size_t, const char *, u_int, struct sshkey_sig_details **);
235 int sshkey_check_sigtype(const u_char *, size_t, const char *);
236 const char *sshkey_sigalg_by_name(const char *);
237 int sshkey_get_sigtype(const u_char *, size_t, char **);
238
239 /* for debug */
240 void sshkey_dump_ec_point(const EC_GROUP *, const EC_POINT *);
241 void sshkey_dump_ec_key(const EC_KEY *);
242
243 /* private key parsing and serialisation */
244 int sshkey_private_serialize(struct sshkey *key, struct sshbuf *buf);
245 int sshkey_private_serialize_opt(struct sshkey *key, struct sshbuf *buf,
246 enum sshkey_serialize_rep);
247 int sshkey_private_deserialize(struct sshbuf *buf, struct sshkey **keyp);
248
249 /* private key file format parsing and serialisation */
250 int sshkey_private_to_fileblob(struct sshkey *key, struct sshbuf *blob,
251 const char *passphrase, const char *comment,
252 int format, const char *openssh_format_cipher, int openssh_format_rounds);
253 int sshkey_parse_private_fileblob(struct sshbuf *buffer,
254 const char *passphrase, struct sshkey **keyp, char **commentp);
255 int sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type,
256 const char *passphrase, struct sshkey **keyp, char **commentp);
257 int sshkey_parse_pubkey_from_private_fileblob_type(struct sshbuf *blob,
258 int type, struct sshkey **pubkeyp);
259
260 /* XXX should be internal, but used by ssh-keygen */
261 int ssh_rsa_complete_crt_parameters(struct sshkey *, const BIGNUM *);
262
263 /* stateful keys (e.g. XMSS) */
264 typedef void sshkey_printfn(const char *, ...) __attribute__((format(printf, 1, 2)));
265 int sshkey_set_filename(struct sshkey *, const char *);
266 int sshkey_enable_maxsign(struct sshkey *, u_int32_t);
267 u_int32_t sshkey_signatures_left(const struct sshkey *);
268 int sshkey_forward_state(const struct sshkey *, u_int32_t, sshkey_printfn *);
269 int sshkey_private_serialize_maxsign(struct sshkey *key, struct sshbuf *buf,
270 u_int32_t maxsign, sshkey_printfn *pr);
271
272 void sshkey_sig_details_free(struct sshkey_sig_details *);
273
274 #ifdef SSHKEY_INTERNAL
275 int ssh_rsa_sign(const struct sshkey *key,
276 u_char **sigp, size_t *lenp, const u_char *data, size_t datalen,
277 const char *ident);
278 int ssh_rsa_verify(const struct sshkey *key,
279 const u_char *sig, size_t siglen, const u_char *data, size_t datalen,
280 const char *alg);
281 int ssh_dss_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
282 const u_char *data, size_t datalen, u_int compat);
283 int ssh_dss_verify(const struct sshkey *key,
284 const u_char *signature, size_t signaturelen,
285 const u_char *data, size_t datalen, u_int compat);
286 int ssh_ecdsa_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
287 const u_char *data, size_t datalen, u_int compat);
288 int ssh_ecdsa_verify(const struct sshkey *key,
289 const u_char *signature, size_t signaturelen,
290 const u_char *data, size_t datalen, u_int compat);
291 int ssh_ecdsa_sk_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 struct sshkey_sig_details **detailsp);
295 int ssh_ed25519_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
296 const u_char *data, size_t datalen, u_int compat);
297 int ssh_ed25519_verify(const struct sshkey *key,
298 const u_char *signature, size_t signaturelen,
299 const u_char *data, size_t datalen, u_int compat);
300 int ssh_ed25519_sk_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 struct sshkey_sig_details **detailsp);
304 int ssh_xmss_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
305 const u_char *data, size_t datalen, u_int compat);
306 int ssh_xmss_verify(const struct sshkey *key,
307 const u_char *signature, size_t signaturelen,
308 const u_char *data, size_t datalen, u_int compat);
309 #endif
310
311 #ifndef WITH_OPENSSL
312 #undef RSA
313 #undef DSA
314 #undef EC_KEY
315 #undef EC_GROUP
316 #undef EC_POINT
317 #endif /* WITH_OPENSSL */
318
319 #endif /* SSHKEY_H */
320