1 /* $OpenBSD: sshkey.h,v 1.61 2022/10/28 00:44:44 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 # ifdef OPENSSL_HAS_ECC 35 # include <openssl/ec.h> 36 # include <openssl/ecdsa.h> 37 # else /* OPENSSL_HAS_ECC */ 38 # define EC_KEY void 39 # define EC_GROUP void 40 # define EC_POINT void 41 # endif /* OPENSSL_HAS_ECC */ 42 #define SSH_OPENSSL_VERSION OpenSSL_version(OPENSSL_VERSION) 43 #else /* WITH_OPENSSL */ 44 # define BIGNUM void 45 # define RSA void 46 # define DSA void 47 # define EC_KEY void 48 # define EC_GROUP void 49 # define EC_POINT void 50 #define SSH_OPENSSL_VERSION "without OpenSSL" 51 #endif /* WITH_OPENSSL */ 52 53 #define SSH_RSA_MINIMUM_MODULUS_SIZE 1024 54 #define SSH_KEY_MAX_SIGN_DATA_SIZE (1 << 20) 55 56 struct sshbuf; 57 58 /* Key types */ 59 enum sshkey_types { 60 KEY_RSA, 61 KEY_DSA, 62 KEY_ECDSA, 63 KEY_ED25519, 64 KEY_RSA_CERT, 65 KEY_DSA_CERT, 66 KEY_ECDSA_CERT, 67 KEY_ED25519_CERT, 68 KEY_XMSS, 69 KEY_XMSS_CERT, 70 KEY_ECDSA_SK, 71 KEY_ECDSA_SK_CERT, 72 KEY_ED25519_SK, 73 KEY_ED25519_SK_CERT, 74 KEY_UNSPEC 75 }; 76 77 /* Default fingerprint hash */ 78 #define SSH_FP_HASH_DEFAULT SSH_DIGEST_SHA256 79 80 /* Fingerprint representation formats */ 81 enum sshkey_fp_rep { 82 SSH_FP_DEFAULT = 0, 83 SSH_FP_HEX, 84 SSH_FP_BASE64, 85 SSH_FP_BUBBLEBABBLE, 86 SSH_FP_RANDOMART 87 }; 88 89 /* Private key serialisation formats, used on the wire */ 90 enum sshkey_serialize_rep { 91 SSHKEY_SERIALIZE_DEFAULT = 0, 92 SSHKEY_SERIALIZE_STATE = 1, /* only state is serialized */ 93 SSHKEY_SERIALIZE_FULL = 2, /* include keys for saving to disk */ 94 SSHKEY_SERIALIZE_SHIELD = 3, /* everything, for encrypting in ram */ 95 SSHKEY_SERIALIZE_INFO = 254, /* minimal information */ 96 }; 97 98 /* Private key disk formats */ 99 enum sshkey_private_format { 100 SSHKEY_PRIVATE_OPENSSH = 0, 101 SSHKEY_PRIVATE_PEM = 1, 102 SSHKEY_PRIVATE_PKCS8 = 2, 103 }; 104 105 /* key is stored in external hardware */ 106 #define SSHKEY_FLAG_EXT 0x0001 107 108 #define SSHKEY_CERT_MAX_PRINCIPALS 256 109 /* XXX opaquify? */ 110 struct sshkey_cert { 111 struct sshbuf *certblob; /* Kept around for use on wire */ 112 u_int type; /* SSH2_CERT_TYPE_USER or SSH2_CERT_TYPE_HOST */ 113 u_int64_t serial; 114 char *key_id; 115 u_int nprincipals; 116 char **principals; 117 u_int64_t valid_after, valid_before; 118 struct sshbuf *critical; 119 struct sshbuf *extensions; 120 struct sshkey *signature_key; 121 char *signature_type; 122 }; 123 124 /* XXX opaquify? */ 125 struct sshkey { 126 int type; 127 int flags; 128 /* KEY_RSA */ 129 RSA *rsa; 130 /* KEY_DSA */ 131 DSA *dsa; 132 /* KEY_ECDSA and KEY_ECDSA_SK */ 133 int ecdsa_nid; /* NID of curve */ 134 EC_KEY *ecdsa; 135 /* KEY_ED25519 and KEY_ED25519_SK */ 136 u_char *ed25519_sk; 137 u_char *ed25519_pk; 138 /* KEY_XMSS */ 139 char *xmss_name; 140 char *xmss_filename; /* for state file updates */ 141 void *xmss_state; /* depends on xmss_name, opaque */ 142 u_char *xmss_sk; 143 u_char *xmss_pk; 144 /* KEY_ECDSA_SK and KEY_ED25519_SK */ 145 char *sk_application; 146 uint8_t sk_flags; 147 struct sshbuf *sk_key_handle; 148 struct sshbuf *sk_reserved; 149 /* Certificates */ 150 struct sshkey_cert *cert; 151 /* Private key shielding */ 152 u_char *shielded_private; 153 size_t shielded_len; 154 u_char *shield_prekey; 155 size_t shield_prekey_len; 156 }; 157 158 #define ED25519_SK_SZ crypto_sign_ed25519_SECRETKEYBYTES 159 #define ED25519_PK_SZ crypto_sign_ed25519_PUBLICKEYBYTES 160 161 /* Additional fields contained in signature */ 162 struct sshkey_sig_details { 163 uint32_t sk_counter; /* U2F signature counter */ 164 uint8_t sk_flags; /* U2F signature flags; see ssh-sk.h */ 165 }; 166 167 struct sshkey_impl_funcs { 168 u_int (*size)(const struct sshkey *); /* optional */ 169 int (*alloc)(struct sshkey *); /* optional */ 170 void (*cleanup)(struct sshkey *); /* optional */ 171 int (*equal)(const struct sshkey *, const struct sshkey *); 172 int (*serialize_public)(const struct sshkey *, struct sshbuf *, 173 enum sshkey_serialize_rep); 174 int (*deserialize_public)(const char *, struct sshbuf *, 175 struct sshkey *); 176 int (*serialize_private)(const struct sshkey *, struct sshbuf *, 177 enum sshkey_serialize_rep); 178 int (*deserialize_private)(const char *, struct sshbuf *, 179 struct sshkey *); 180 int (*generate)(struct sshkey *, int); /* optional */ 181 int (*copy_public)(const struct sshkey *, struct sshkey *); 182 int (*sign)(struct sshkey *, u_char **, size_t *, 183 const u_char *, size_t, const char *, 184 const char *, const char *, u_int); /* optional */ 185 int (*verify)(const struct sshkey *, const u_char *, size_t, 186 const u_char *, size_t, const char *, u_int, 187 struct sshkey_sig_details **); 188 }; 189 190 struct sshkey_impl { 191 const char *name; 192 const char *shortname; 193 const char *sigalg; 194 int type; 195 int nid; 196 int cert; 197 int sigonly; 198 int keybits; 199 const struct sshkey_impl_funcs *funcs; 200 }; 201 202 struct sshkey *sshkey_new(int); 203 void sshkey_free(struct sshkey *); 204 int sshkey_equal_public(const struct sshkey *, 205 const struct sshkey *); 206 int sshkey_equal(const struct sshkey *, const struct sshkey *); 207 char *sshkey_fingerprint(const struct sshkey *, 208 int, enum sshkey_fp_rep); 209 int sshkey_fingerprint_raw(const struct sshkey *k, 210 int, u_char **retp, size_t *lenp); 211 const char *sshkey_type(const struct sshkey *); 212 const char *sshkey_cert_type(const struct sshkey *); 213 int sshkey_format_text(const struct sshkey *, struct sshbuf *); 214 int sshkey_write(const struct sshkey *, FILE *); 215 int sshkey_read(struct sshkey *, char **); 216 u_int sshkey_size(const struct sshkey *); 217 218 int sshkey_generate(int type, u_int bits, struct sshkey **keyp); 219 int sshkey_from_private(const struct sshkey *, struct sshkey **); 220 221 int sshkey_is_shielded(struct sshkey *); 222 int sshkey_shield_private(struct sshkey *); 223 int sshkey_unshield_private(struct sshkey *); 224 225 int sshkey_type_from_name(const char *); 226 int sshkey_is_cert(const struct sshkey *); 227 int sshkey_is_sk(const struct sshkey *); 228 int sshkey_type_is_cert(int); 229 int sshkey_type_plain(int); 230 231 /* Returns non-zero if key name match sigalgs pattern list. (handles RSA) */ 232 int sshkey_match_keyname_to_sigalgs(const char *, const char *); 233 234 int sshkey_to_certified(struct sshkey *); 235 int sshkey_drop_cert(struct sshkey *); 236 int sshkey_cert_copy(const struct sshkey *, struct sshkey *); 237 int sshkey_cert_check_authority(const struct sshkey *, int, int, int, 238 uint64_t, const char *, const char **); 239 int sshkey_cert_check_authority_now(const struct sshkey *, int, int, int, 240 const char *, const char **); 241 int sshkey_cert_check_host(const struct sshkey *, const char *, 242 int , const char *, const char **); 243 size_t sshkey_format_cert_validity(const struct sshkey_cert *, 244 char *, size_t) __attribute__((__bounded__(__string__, 2, 3))); 245 int sshkey_check_cert_sigtype(const struct sshkey *, const char *); 246 247 int sshkey_certify(struct sshkey *, struct sshkey *, 248 const char *, const char *, const char *); 249 /* Variant allowing use of a custom signature function (e.g. for ssh-agent) */ 250 typedef int sshkey_certify_signer(struct sshkey *, u_char **, size_t *, 251 const u_char *, size_t, const char *, const char *, const char *, 252 u_int, void *); 253 int sshkey_certify_custom(struct sshkey *, struct sshkey *, const char *, 254 const char *, const char *, sshkey_certify_signer *, void *); 255 256 int sshkey_ecdsa_nid_from_name(const char *); 257 int sshkey_curve_name_to_nid(const char *); 258 const char * sshkey_curve_nid_to_name(int); 259 u_int sshkey_curve_nid_to_bits(int); 260 int sshkey_ecdsa_bits_to_nid(int); 261 int sshkey_ecdsa_key_to_nid(EC_KEY *); 262 int sshkey_ec_nid_to_hash_alg(int nid); 263 int sshkey_ec_validate_public(const EC_GROUP *, const EC_POINT *); 264 int sshkey_ec_validate_private(const EC_KEY *); 265 const char *sshkey_ssh_name(const struct sshkey *); 266 const char *sshkey_ssh_name_plain(const struct sshkey *); 267 int sshkey_names_valid2(const char *, int); 268 char *sshkey_alg_list(int, int, int, char); 269 270 int sshkey_from_blob(const u_char *, size_t, struct sshkey **); 271 int sshkey_fromb(struct sshbuf *, struct sshkey **); 272 int sshkey_froms(struct sshbuf *, struct sshkey **); 273 int sshkey_to_blob(const struct sshkey *, u_char **, size_t *); 274 int sshkey_to_base64(const struct sshkey *, char **); 275 int sshkey_putb(const struct sshkey *, struct sshbuf *); 276 int sshkey_puts(const struct sshkey *, struct sshbuf *); 277 int sshkey_puts_opts(const struct sshkey *, struct sshbuf *, 278 enum sshkey_serialize_rep); 279 int sshkey_plain_to_blob(const struct sshkey *, u_char **, size_t *); 280 int sshkey_putb_plain(const struct sshkey *, struct sshbuf *); 281 282 int sshkey_sign(struct sshkey *, u_char **, size_t *, 283 const u_char *, size_t, const char *, const char *, const char *, u_int); 284 int sshkey_verify(const struct sshkey *, const u_char *, size_t, 285 const u_char *, size_t, const char *, u_int, struct sshkey_sig_details **); 286 int sshkey_check_sigtype(const u_char *, size_t, const char *); 287 const char *sshkey_sigalg_by_name(const char *); 288 int sshkey_get_sigtype(const u_char *, size_t, char **); 289 290 /* for debug */ 291 void sshkey_dump_ec_point(const EC_GROUP *, const EC_POINT *); 292 void sshkey_dump_ec_key(const EC_KEY *); 293 294 /* private key parsing and serialisation */ 295 int sshkey_private_serialize(struct sshkey *key, struct sshbuf *buf); 296 int sshkey_private_serialize_opt(struct sshkey *key, struct sshbuf *buf, 297 enum sshkey_serialize_rep); 298 int sshkey_private_deserialize(struct sshbuf *buf, struct sshkey **keyp); 299 300 /* private key file format parsing and serialisation */ 301 int sshkey_private_to_fileblob(struct sshkey *key, struct sshbuf *blob, 302 const char *passphrase, const char *comment, 303 int format, const char *openssh_format_cipher, int openssh_format_rounds); 304 int sshkey_parse_private_fileblob(struct sshbuf *buffer, 305 const char *passphrase, struct sshkey **keyp, char **commentp); 306 int sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type, 307 const char *passphrase, struct sshkey **keyp, char **commentp); 308 int sshkey_parse_pubkey_from_private_fileblob_type(struct sshbuf *blob, 309 int type, struct sshkey **pubkeyp); 310 311 int sshkey_check_rsa_length(const struct sshkey *, int); 312 /* XXX should be internal, but used by ssh-keygen */ 313 int ssh_rsa_complete_crt_parameters(struct sshkey *, const BIGNUM *); 314 315 /* stateful keys (e.g. XMSS) */ 316 int sshkey_set_filename(struct sshkey *, const char *); 317 int sshkey_enable_maxsign(struct sshkey *, u_int32_t); 318 u_int32_t sshkey_signatures_left(const struct sshkey *); 319 int sshkey_forward_state(const struct sshkey *, u_int32_t, int); 320 int sshkey_private_serialize_maxsign(struct sshkey *key, 321 struct sshbuf *buf, u_int32_t maxsign, int); 322 323 void sshkey_sig_details_free(struct sshkey_sig_details *); 324 325 #ifdef SSHKEY_INTERNAL 326 int sshkey_sk_fields_equal(const struct sshkey *a, const struct sshkey *b); 327 void sshkey_sk_cleanup(struct sshkey *k); 328 int sshkey_serialize_sk(const struct sshkey *key, struct sshbuf *b); 329 int sshkey_copy_public_sk(const struct sshkey *from, struct sshkey *to); 330 int sshkey_deserialize_sk(struct sshbuf *b, struct sshkey *key); 331 int sshkey_serialize_private_sk(const struct sshkey *key, 332 struct sshbuf *buf); 333 int sshkey_private_deserialize_sk(struct sshbuf *buf, struct sshkey *k); 334 #ifdef WITH_OPENSSL 335 int check_rsa_length(const RSA *rsa); /* XXX remove */ 336 #endif 337 #endif 338 339 #if !defined(WITH_OPENSSL) 340 # undef RSA 341 # undef DSA 342 # undef EC_KEY 343 # undef EC_GROUP 344 # undef EC_POINT 345 #elif !defined(OPENSSL_HAS_ECC) 346 # undef EC_KEY 347 # undef EC_GROUP 348 # undef EC_POINT 349 #endif 350 351 #endif /* SSHKEY_H */ 352