1 /* $NetBSD: sshkey.h,v 1.21 2024/09/24 21:32:19 christos Exp $ */ 2 /* $OpenBSD: sshkey.h,v 1.65 2024/09/04 05:33:34 djm Exp $ */ 3 4 /* 5 * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 #ifndef SSHKEY_H 28 #define SSHKEY_H 29 30 #include "includes.h" 31 #include <sys/types.h> 32 33 #ifdef WITH_OPENSSL 34 #include <openssl/rsa.h> 35 #include <openssl/dsa.h> 36 #include <openssl/ec.h> 37 #include <openssl/ecdsa.h> 38 #include <openssl/evp.h> 39 #define SSH_OPENSSL_VERSION OpenSSL_version(OPENSSL_VERSION) 40 #else /* OPENSSL */ 41 #define BIGNUM void 42 #define RSA void 43 #define DSA void 44 #define EC_KEY void 45 #define EC_GROUP void 46 #define EC_POINT void 47 #define EVP_PKEY void 48 #define SSH_OPENSSL_VERSION "without OpenSSL" 49 #endif /* WITH_OPENSSL */ 50 51 #define SSH_RSA_MINIMUM_MODULUS_SIZE 1024 52 #define SSH_KEY_MAX_SIGN_DATA_SIZE (1 << 20) 53 54 struct sshbuf; 55 56 /* Key types */ 57 enum sshkey_types { 58 KEY_RSA, 59 KEY_DSA, 60 KEY_ECDSA, 61 KEY_ED25519, 62 KEY_RSA_CERT, 63 KEY_DSA_CERT, 64 KEY_ECDSA_CERT, 65 KEY_ED25519_CERT, 66 KEY_XMSS, 67 KEY_XMSS_CERT, 68 KEY_ECDSA_SK, 69 KEY_ECDSA_SK_CERT, 70 KEY_ED25519_SK, 71 KEY_ED25519_SK_CERT, 72 KEY_UNSPEC 73 }; 74 75 /* Default fingerprint hash */ 76 #define SSH_FP_HASH_DEFAULT SSH_DIGEST_SHA256 77 78 /* Fingerprint representation formats */ 79 enum sshkey_fp_rep { 80 SSH_FP_DEFAULT = 0, 81 SSH_FP_HEX, 82 SSH_FP_BASE64, 83 SSH_FP_BUBBLEBABBLE, 84 SSH_FP_RANDOMART 85 }; 86 87 /* Private key serialisation formats, used on the wire */ 88 enum sshkey_serialize_rep { 89 SSHKEY_SERIALIZE_DEFAULT = 0, 90 SSHKEY_SERIALIZE_STATE = 1, /* only state is serialized */ 91 SSHKEY_SERIALIZE_FULL = 2, /* include keys for saving to disk */ 92 SSHKEY_SERIALIZE_SHIELD = 3, /* everything, for encrypting in ram */ 93 SSHKEY_SERIALIZE_INFO = 254, /* minimal information */ 94 }; 95 96 /* Private key disk formats */ 97 enum sshkey_private_format { 98 SSHKEY_PRIVATE_OPENSSH = 0, 99 SSHKEY_PRIVATE_PEM = 1, 100 SSHKEY_PRIVATE_PKCS8 = 2, 101 }; 102 103 /* key is stored in external hardware */ 104 #define SSHKEY_FLAG_EXT 0x0001 105 106 #define SSHKEY_CERT_MAX_PRINCIPALS 256 107 /* XXX opaquify? */ 108 struct sshkey_cert { 109 struct sshbuf *certblob; /* Kept around for use on wire */ 110 u_int type; /* SSH2_CERT_TYPE_USER or SSH2_CERT_TYPE_HOST */ 111 u_int64_t serial; 112 char *key_id; 113 u_int nprincipals; 114 char **principals; 115 u_int64_t valid_after, valid_before; 116 struct sshbuf *critical; 117 struct sshbuf *extensions; 118 struct sshkey *signature_key; 119 char *signature_type; 120 }; 121 122 /* XXX opaquify? */ 123 struct sshkey { 124 int type; 125 int flags; 126 /* KEY_DSA */ 127 DSA *dsa; 128 /* KEY_ECDSA and KEY_ECDSA_SK */ 129 int ecdsa_nid; /* NID of curve */ 130 /* libcrypto-backed keys */ 131 EVP_PKEY *pkey; 132 /* KEY_ED25519 and KEY_ED25519_SK */ 133 u_char *ed25519_sk; 134 u_char *ed25519_pk; 135 /* KEY_XMSS */ 136 char *xmss_name; 137 char *xmss_filename; /* for state file updates */ 138 void *xmss_state; /* depends on xmss_name, opaque */ 139 u_char *xmss_sk; 140 u_char *xmss_pk; 141 /* KEY_ECDSA_SK and KEY_ED25519_SK */ 142 char *sk_application; 143 uint8_t sk_flags; 144 struct sshbuf *sk_key_handle; 145 struct sshbuf *sk_reserved; 146 /* Certificates */ 147 struct sshkey_cert *cert; 148 /* Private key shielding */ 149 u_char *shielded_private; 150 size_t shielded_len; 151 u_char *shield_prekey; 152 size_t shield_prekey_len; 153 }; 154 155 #define ED25519_SK_SZ crypto_sign_ed25519_SECRETKEYBYTES 156 #define ED25519_PK_SZ crypto_sign_ed25519_PUBLICKEYBYTES 157 158 /* Additional fields contained in signature */ 159 struct sshkey_sig_details { 160 uint32_t sk_counter; /* U2F signature counter */ 161 uint8_t sk_flags; /* U2F signature flags; see ssh-sk.h */ 162 }; 163 164 struct sshkey_impl_funcs { 165 u_int (*size)(const struct sshkey *); /* optional */ 166 int (*alloc)(struct sshkey *); /* optional */ 167 void (*cleanup)(struct sshkey *); /* optional */ 168 int (*equal)(const struct sshkey *, const struct sshkey *); 169 int (*serialize_public)(const struct sshkey *, struct sshbuf *, 170 enum sshkey_serialize_rep); 171 int (*deserialize_public)(const char *, struct sshbuf *, 172 struct sshkey *); 173 int (*serialize_private)(const struct sshkey *, struct sshbuf *, 174 enum sshkey_serialize_rep); 175 int (*deserialize_private)(const char *, struct sshbuf *, 176 struct sshkey *); 177 int (*generate)(struct sshkey *, int); /* optional */ 178 int (*copy_public)(const struct sshkey *, struct sshkey *); 179 int (*sign)(struct sshkey *, u_char **, size_t *, 180 const u_char *, size_t, const char *, 181 const char *, const char *, u_int); /* optional */ 182 int (*verify)(const struct sshkey *, const u_char *, size_t, 183 const u_char *, size_t, const char *, u_int, 184 struct sshkey_sig_details **); 185 }; 186 187 struct sshkey_impl { 188 const char *name; 189 const char *shortname; 190 const char *sigalg; 191 int type; 192 int nid; 193 int cert; 194 int sigonly; 195 int keybits; 196 const struct sshkey_impl_funcs *funcs; 197 }; 198 199 struct sshkey *sshkey_new(int); 200 void sshkey_free(struct sshkey *); 201 int sshkey_equal_public(const struct sshkey *, 202 const struct sshkey *); 203 int sshkey_equal(const struct sshkey *, const struct sshkey *); 204 char *sshkey_fingerprint(const struct sshkey *, 205 int, enum sshkey_fp_rep); 206 int sshkey_fingerprint_raw(const struct sshkey *k, 207 int, u_char **retp, size_t *lenp); 208 const char *sshkey_type(const struct sshkey *); 209 const char *sshkey_cert_type(const struct sshkey *); 210 int sshkey_format_text(const struct sshkey *, struct sshbuf *); 211 int sshkey_write(const struct sshkey *, FILE *); 212 int sshkey_read(struct sshkey *, char **); 213 u_int sshkey_size(const struct sshkey *); 214 215 int sshkey_generate(int type, u_int bits, struct sshkey **keyp); 216 int sshkey_from_private(const struct sshkey *, struct sshkey **); 217 218 int sshkey_is_shielded(struct sshkey *); 219 int sshkey_shield_private(struct sshkey *); 220 int sshkey_unshield_private(struct sshkey *); 221 222 int sshkey_type_from_name(const char *); 223 int sshkey_type_from_shortname(const char *); 224 int sshkey_is_cert(const struct sshkey *); 225 int sshkey_is_sk(const struct sshkey *); 226 int sshkey_type_is_cert(int); 227 int sshkey_type_plain(int); 228 229 /* Returns non-zero if key name match sigalgs pattern list. (handles RSA) */ 230 int sshkey_match_keyname_to_sigalgs(const char *, const char *); 231 232 int sshkey_to_certified(struct sshkey *); 233 int sshkey_drop_cert(struct sshkey *); 234 int sshkey_cert_copy(const struct sshkey *, struct sshkey *); 235 int sshkey_cert_check_authority(const struct sshkey *, int, int, int, 236 uint64_t, const char *, const char **); 237 int sshkey_cert_check_authority_now(const struct sshkey *, int, int, int, 238 const char *, const char **); 239 int sshkey_cert_check_host(const struct sshkey *, const char *, 240 int , const char *, const char **); 241 size_t sshkey_format_cert_validity(const struct sshkey_cert *, 242 char *, size_t) __attribute__((__bounded__(__string__, 2, 3))); 243 int sshkey_check_cert_sigtype(const struct sshkey *, const char *); 244 245 int sshkey_certify(struct sshkey *, struct sshkey *, 246 const char *, const char *, const char *); 247 /* Variant allowing use of a custom signature function (e.g. for ssh-agent) */ 248 typedef int sshkey_certify_signer(struct sshkey *, u_char **, size_t *, 249 const u_char *, size_t, const char *, const char *, const char *, 250 u_int, void *); 251 int sshkey_certify_custom(struct sshkey *, struct sshkey *, const char *, 252 const char *, const char *, sshkey_certify_signer *, void *); 253 254 int sshkey_ecdsa_nid_from_name(const char *); 255 int sshkey_curve_name_to_nid(const char *); 256 const char * sshkey_curve_nid_to_name(int); 257 u_int sshkey_curve_nid_to_bits(int); 258 int sshkey_ecdsa_bits_to_nid(int); 259 int sshkey_ecdsa_key_to_nid(const EC_KEY *); 260 int sshkey_ecdsa_pkey_to_nid(EVP_PKEY *); 261 int sshkey_ec_nid_to_hash_alg(int nid); 262 int sshkey_ec_validate_public(const EC_GROUP *, const EC_POINT *); 263 int sshkey_ec_validate_private(const EC_KEY *); 264 const char *sshkey_ssh_name(const struct sshkey *); 265 const char *sshkey_ssh_name_plain(const struct sshkey *); 266 int sshkey_names_valid2(const char *, int, int); 267 char *sshkey_alg_list(int, int, int, char); 268 269 int sshkey_from_blob(const u_char *, size_t, struct sshkey **); 270 int sshkey_fromb(struct sshbuf *, struct sshkey **); 271 int sshkey_froms(struct sshbuf *, struct sshkey **); 272 int sshkey_to_blob(const struct sshkey *, u_char **, size_t *); 273 int sshkey_to_base64(const struct sshkey *, char **); 274 int sshkey_putb(const struct sshkey *, struct sshbuf *); 275 int sshkey_puts(const struct sshkey *, struct sshbuf *); 276 int sshkey_puts_opts(const struct sshkey *, struct sshbuf *, 277 enum sshkey_serialize_rep); 278 int sshkey_plain_to_blob(const struct sshkey *, u_char **, size_t *); 279 int sshkey_putb_plain(const struct sshkey *, struct sshbuf *); 280 281 int sshkey_sign(struct sshkey *, u_char **, size_t *, 282 const u_char *, size_t, const char *, const char *, const char *, u_int); 283 int sshkey_verify(const struct sshkey *, const u_char *, size_t, 284 const u_char *, size_t, const char *, u_int, struct sshkey_sig_details **); 285 int sshkey_check_sigtype(const u_char *, size_t, const char *); 286 const char *sshkey_sigalg_by_name(const char *); 287 int sshkey_get_sigtype(const u_char *, size_t, char **); 288 289 /* Signing and verification backend for libcrypto-backed keys */ 290 int sshkey_pkey_digest_sign(EVP_PKEY*, int, u_char **, 291 size_t *, const u_char *, size_t); 292 int sshkey_pkey_digest_verify(EVP_PKEY *, int, const u_char *, 293 size_t, u_char *, size_t); 294 295 /* for debug */ 296 void sshkey_dump_ec_point(const EC_GROUP *, const EC_POINT *); 297 void sshkey_dump_ec_key(const EC_KEY *); 298 299 /* private key parsing and serialisation */ 300 int sshkey_private_serialize(struct sshkey *key, struct sshbuf *buf); 301 int sshkey_private_serialize_opt(struct sshkey *key, struct sshbuf *buf, 302 enum sshkey_serialize_rep); 303 int sshkey_private_deserialize(struct sshbuf *buf, struct sshkey **keyp); 304 305 /* private key file format parsing and serialisation */ 306 int sshkey_private_to_fileblob(struct sshkey *key, struct sshbuf *blob, 307 const char *passphrase, const char *comment, 308 int format, const char *openssh_format_cipher, int openssh_format_rounds); 309 int sshkey_parse_private_fileblob(struct sshbuf *buffer, 310 const char *passphrase, struct sshkey **keyp, char **commentp); 311 int sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type, 312 const char *passphrase, struct sshkey **keyp, char **commentp); 313 int sshkey_parse_pubkey_from_private_fileblob_type(struct sshbuf *blob, 314 int type, struct sshkey **pubkeyp); 315 316 int sshkey_check_rsa_length(const struct sshkey *, int); 317 /* XXX should be internal, but used by ssh-keygen */ 318 int ssh_rsa_complete_crt_parameters(const BIGNUM *, const BIGNUM *, 319 const BIGNUM *, const BIGNUM *, BIGNUM **, BIGNUM **); 320 321 /* stateful keys (e.g. XMSS) */ 322 int sshkey_set_filename(struct sshkey *, const char *); 323 int sshkey_enable_maxsign(struct sshkey *, u_int32_t); 324 u_int32_t sshkey_signatures_left(const struct sshkey *); 325 int sshkey_private_serialize_maxsign(struct sshkey *key, 326 struct sshbuf *buf, u_int32_t maxsign, int); 327 328 void sshkey_sig_details_free(struct sshkey_sig_details *); 329 330 #ifdef WITH_OPENSSL 331 int sshkey_ecdsa_fixup_group(EVP_PKEY *k); /* ssh-ecdsa.c */ 332 #endif 333 334 #ifdef SSHKEY_INTERNAL 335 int sshkey_sk_fields_equal(const struct sshkey *a, const struct sshkey *b); 336 void sshkey_sk_cleanup(struct sshkey *k); 337 int sshkey_serialize_sk(const struct sshkey *key, struct sshbuf *b); 338 int sshkey_copy_public_sk(const struct sshkey *from, struct sshkey *to); 339 int sshkey_deserialize_sk(struct sshbuf *b, struct sshkey *key); 340 int sshkey_serialize_private_sk(const struct sshkey *key, 341 struct sshbuf *buf); 342 int sshkey_private_deserialize_sk(struct sshbuf *buf, struct sshkey *k); 343 #ifdef WITH_OPENSSL 344 int check_rsa_length(const RSA *rsa); /* XXX remove */ 345 #endif 346 #endif 347 348 #ifndef WITH_OPENSSL 349 #undef RSA 350 #undef DSA 351 #undef EC_KEY 352 #undef EC_GROUP 353 #undef EC_POINT 354 #undef EVP_PKEY 355 #endif /* WITH_OPENSSL */ 356 357 #endif /* SSHKEY_H */ 358