1 /* $OpenBSD: sshkey.h,v 1.43 2019/12/30 09:21:59 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 #else /* WITH_OPENSSL */ 43 # define BIGNUM void 44 # define RSA void 45 # define DSA void 46 # define EC_KEY void 47 # define EC_GROUP void 48 # define EC_POINT void 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 /* Version of protocol expected from ssh-sk-helper */ 55 #define SSH_SK_HELPER_VERSION 2 56 57 /* ssh-sk-helper messages */ 58 #define SSH_SK_HELPER_SIGN 1 59 #define SSH_SK_HELPER_ENROLL 2 60 #define SSH_SK_HELPER_LOAD_RESIDENT 3 61 62 struct sshbuf; 63 64 /* Key types */ 65 enum sshkey_types { 66 KEY_RSA, 67 KEY_DSA, 68 KEY_ECDSA, 69 KEY_ED25519, 70 KEY_RSA_CERT, 71 KEY_DSA_CERT, 72 KEY_ECDSA_CERT, 73 KEY_ED25519_CERT, 74 KEY_XMSS, 75 KEY_XMSS_CERT, 76 KEY_ECDSA_SK, 77 KEY_ECDSA_SK_CERT, 78 KEY_ED25519_SK, 79 KEY_ED25519_SK_CERT, 80 KEY_UNSPEC 81 }; 82 83 /* Default fingerprint hash */ 84 #define SSH_FP_HASH_DEFAULT SSH_DIGEST_SHA256 85 86 /* Fingerprint representation formats */ 87 enum sshkey_fp_rep { 88 SSH_FP_DEFAULT = 0, 89 SSH_FP_HEX, 90 SSH_FP_BASE64, 91 SSH_FP_BUBBLEBABBLE, 92 SSH_FP_RANDOMART 93 }; 94 95 /* Private key serialisation formats, used on the wire */ 96 enum sshkey_serialize_rep { 97 SSHKEY_SERIALIZE_DEFAULT = 0, 98 SSHKEY_SERIALIZE_STATE = 1, /* only state is serialized */ 99 SSHKEY_SERIALIZE_FULL = 2, /* include keys for saving to disk */ 100 SSHKEY_SERIALIZE_SHIELD = 3, /* everything, for encrypting in ram */ 101 SSHKEY_SERIALIZE_INFO = 254, /* minimal information */ 102 }; 103 104 /* Private key disk formats */ 105 enum sshkey_private_format { 106 SSHKEY_PRIVATE_OPENSSH = 0, 107 SSHKEY_PRIVATE_PEM = 1, 108 SSHKEY_PRIVATE_PKCS8 = 2, 109 }; 110 111 /* key is stored in external hardware */ 112 #define SSHKEY_FLAG_EXT 0x0001 113 114 #define SSHKEY_CERT_MAX_PRINCIPALS 256 115 /* XXX opaquify? */ 116 struct sshkey_cert { 117 struct sshbuf *certblob; /* Kept around for use on wire */ 118 u_int type; /* SSH2_CERT_TYPE_USER or SSH2_CERT_TYPE_HOST */ 119 u_int64_t serial; 120 char *key_id; 121 u_int nprincipals; 122 char **principals; 123 u_int64_t valid_after, valid_before; 124 struct sshbuf *critical; 125 struct sshbuf *extensions; 126 struct sshkey *signature_key; 127 char *signature_type; 128 }; 129 130 /* XXX opaquify? */ 131 struct sshkey { 132 int type; 133 int flags; 134 /* KEY_RSA */ 135 RSA *rsa; 136 /* KEY_DSA */ 137 DSA *dsa; 138 /* KEY_ECDSA and KEY_ECDSA_SK */ 139 int ecdsa_nid; /* NID of curve */ 140 EC_KEY *ecdsa; 141 /* KEY_ED25519 and KEY_ED25519_SK */ 142 u_char *ed25519_sk; 143 u_char *ed25519_pk; 144 /* KEY_XMSS */ 145 char *xmss_name; 146 char *xmss_filename; /* for state file updates */ 147 void *xmss_state; /* depends on xmss_name, opaque */ 148 u_char *xmss_sk; 149 u_char *xmss_pk; 150 /* KEY_ECDSA_SK and KEY_ED25519_SK */ 151 char *sk_application; 152 uint8_t sk_flags; 153 struct sshbuf *sk_key_handle; 154 struct sshbuf *sk_reserved; 155 /* Certificates */ 156 struct sshkey_cert *cert; 157 /* Private key shielding */ 158 u_char *shielded_private; 159 size_t shielded_len; 160 u_char *shield_prekey; 161 size_t shield_prekey_len; 162 }; 163 164 #define ED25519_SK_SZ crypto_sign_ed25519_SECRETKEYBYTES 165 #define ED25519_PK_SZ crypto_sign_ed25519_PUBLICKEYBYTES 166 167 /* Additional fields contained in signature */ 168 struct sshkey_sig_details { 169 uint32_t sk_counter; /* U2F signature counter */ 170 uint8_t sk_flags; /* U2F signature flags; see ssh-sk.h */ 171 }; 172 173 struct sshkey *sshkey_new(int); 174 void sshkey_free(struct sshkey *); 175 int sshkey_equal_public(const struct sshkey *, 176 const struct sshkey *); 177 int sshkey_equal(const struct sshkey *, const struct sshkey *); 178 char *sshkey_fingerprint(const struct sshkey *, 179 int, enum sshkey_fp_rep); 180 int sshkey_fingerprint_raw(const struct sshkey *k, 181 int, u_char **retp, size_t *lenp); 182 const char *sshkey_type(const struct sshkey *); 183 const char *sshkey_cert_type(const struct sshkey *); 184 int sshkey_format_text(const struct sshkey *, struct sshbuf *); 185 int sshkey_write(const struct sshkey *, FILE *); 186 int sshkey_read(struct sshkey *, char **); 187 u_int sshkey_size(const struct sshkey *); 188 189 int sshkey_generate(int type, u_int bits, struct sshkey **keyp); 190 int sshkey_from_private(const struct sshkey *, struct sshkey **); 191 192 int sshkey_is_shielded(struct sshkey *); 193 int sshkey_shield_private(struct sshkey *); 194 int sshkey_unshield_private(struct sshkey *); 195 196 int sshkey_type_from_name(const char *); 197 int sshkey_is_cert(const struct sshkey *); 198 int sshkey_is_sk(const struct sshkey *); 199 int sshkey_type_is_cert(int); 200 int sshkey_type_plain(int); 201 int sshkey_to_certified(struct sshkey *); 202 int sshkey_drop_cert(struct sshkey *); 203 int sshkey_cert_copy(const struct sshkey *, struct sshkey *); 204 int sshkey_cert_check_authority(const struct sshkey *, int, int, 205 const char *, const char **); 206 size_t sshkey_format_cert_validity(const struct sshkey_cert *, 207 char *, size_t) __attribute__((__bounded__(__string__, 2, 3))); 208 int sshkey_check_cert_sigtype(const struct sshkey *, const char *); 209 210 int sshkey_certify(struct sshkey *, struct sshkey *, 211 const char *, const char *); 212 /* Variant allowing use of a custom signature function (e.g. for ssh-agent) */ 213 typedef int sshkey_certify_signer(struct sshkey *, u_char **, size_t *, 214 const u_char *, size_t, const char *, const char *, u_int, void *); 215 int sshkey_certify_custom(struct sshkey *, struct sshkey *, const char *, 216 const char *, sshkey_certify_signer *, void *); 217 218 int sshkey_ecdsa_nid_from_name(const char *); 219 int sshkey_curve_name_to_nid(const char *); 220 const char * sshkey_curve_nid_to_name(int); 221 u_int sshkey_curve_nid_to_bits(int); 222 int sshkey_ecdsa_bits_to_nid(int); 223 int sshkey_ecdsa_key_to_nid(EC_KEY *); 224 int sshkey_ec_nid_to_hash_alg(int nid); 225 int sshkey_ec_validate_public(const EC_GROUP *, const EC_POINT *); 226 int sshkey_ec_validate_private(const EC_KEY *); 227 const char *sshkey_ssh_name(const struct sshkey *); 228 const char *sshkey_ssh_name_plain(const struct sshkey *); 229 int sshkey_names_valid2(const char *, int); 230 char *sshkey_alg_list(int, int, int, char); 231 232 int sshkey_from_blob(const u_char *, size_t, struct sshkey **); 233 int sshkey_fromb(struct sshbuf *, struct sshkey **); 234 int sshkey_froms(struct sshbuf *, struct sshkey **); 235 int sshkey_to_blob(const struct sshkey *, u_char **, size_t *); 236 int sshkey_to_base64(const struct sshkey *, char **); 237 int sshkey_putb(const struct sshkey *, struct sshbuf *); 238 int sshkey_puts(const struct sshkey *, struct sshbuf *); 239 int sshkey_puts_opts(const struct sshkey *, struct sshbuf *, 240 enum sshkey_serialize_rep); 241 int sshkey_plain_to_blob(const struct sshkey *, u_char **, size_t *); 242 int sshkey_putb_plain(const struct sshkey *, struct sshbuf *); 243 244 int sshkey_sign(struct sshkey *, u_char **, size_t *, 245 const u_char *, size_t, const char *, const char *, u_int); 246 int sshkey_verify(const struct sshkey *, const u_char *, size_t, 247 const u_char *, size_t, const char *, u_int, struct sshkey_sig_details **); 248 int sshkey_check_sigtype(const u_char *, size_t, const char *); 249 const char *sshkey_sigalg_by_name(const char *); 250 int sshkey_get_sigtype(const u_char *, size_t, char **); 251 252 /* for debug */ 253 void sshkey_dump_ec_point(const EC_GROUP *, const EC_POINT *); 254 void sshkey_dump_ec_key(const EC_KEY *); 255 256 /* private key parsing and serialisation */ 257 int sshkey_private_serialize(struct sshkey *key, struct sshbuf *buf); 258 int sshkey_private_serialize_opt(struct sshkey *key, struct sshbuf *buf, 259 enum sshkey_serialize_rep); 260 int sshkey_private_deserialize(struct sshbuf *buf, struct sshkey **keyp); 261 262 /* private key file format parsing and serialisation */ 263 int sshkey_private_to_fileblob(struct sshkey *key, struct sshbuf *blob, 264 const char *passphrase, const char *comment, 265 int format, const char *openssh_format_cipher, int openssh_format_rounds); 266 int sshkey_parse_private_fileblob(struct sshbuf *buffer, 267 const char *passphrase, struct sshkey **keyp, char **commentp); 268 int sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type, 269 const char *passphrase, struct sshkey **keyp, char **commentp); 270 271 /* XXX should be internal, but used by ssh-keygen */ 272 int ssh_rsa_complete_crt_parameters(struct sshkey *, const BIGNUM *); 273 274 /* stateful keys (e.g. XMSS) */ 275 #ifdef NO_ATTRIBUTE_ON_PROTOTYPE_ARGS 276 typedef void sshkey_printfn(const char *, ...); 277 #else 278 typedef void sshkey_printfn(const char *, ...) __attribute__((format(printf, 1, 2))); 279 #endif 280 int sshkey_set_filename(struct sshkey *, const char *); 281 int sshkey_enable_maxsign(struct sshkey *, u_int32_t); 282 u_int32_t sshkey_signatures_left(const struct sshkey *); 283 int sshkey_forward_state(const struct sshkey *, u_int32_t, sshkey_printfn *); 284 int sshkey_private_serialize_maxsign(struct sshkey *key, struct sshbuf *buf, 285 u_int32_t maxsign, sshkey_printfn *pr); 286 287 void sshkey_sig_details_free(struct sshkey_sig_details *); 288 289 #ifdef SSHKEY_INTERNAL 290 int ssh_rsa_sign(const struct sshkey *key, 291 u_char **sigp, size_t *lenp, const u_char *data, size_t datalen, 292 const char *ident); 293 int ssh_rsa_verify(const struct sshkey *key, 294 const u_char *sig, size_t siglen, const u_char *data, size_t datalen, 295 const char *alg); 296 int ssh_dss_sign(const struct sshkey *key, u_char **sigp, size_t *lenp, 297 const u_char *data, size_t datalen, u_int compat); 298 int ssh_dss_verify(const struct sshkey *key, 299 const u_char *signature, size_t signaturelen, 300 const u_char *data, size_t datalen, u_int compat); 301 int ssh_ecdsa_sign(const struct sshkey *key, u_char **sigp, size_t *lenp, 302 const u_char *data, size_t datalen, u_int compat); 303 int ssh_ecdsa_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 int ssh_ecdsa_sk_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 struct sshkey_sig_details **detailsp); 310 int ssh_ed25519_sign(const struct sshkey *key, u_char **sigp, size_t *lenp, 311 const u_char *data, size_t datalen, u_int compat); 312 int ssh_ed25519_verify(const struct sshkey *key, 313 const u_char *signature, size_t signaturelen, 314 const u_char *data, size_t datalen, u_int compat); 315 int ssh_ed25519_sk_verify(const struct sshkey *key, 316 const u_char *signature, size_t signaturelen, 317 const u_char *data, size_t datalen, u_int compat, 318 struct sshkey_sig_details **detailsp); 319 int ssh_xmss_sign(const struct sshkey *key, u_char **sigp, size_t *lenp, 320 const u_char *data, size_t datalen, u_int compat); 321 int ssh_xmss_verify(const struct sshkey *key, 322 const u_char *signature, size_t signaturelen, 323 const u_char *data, size_t datalen, u_int compat); 324 #endif 325 326 #if !defined(WITH_OPENSSL) 327 # undef RSA 328 # undef DSA 329 # undef EC_KEY 330 # undef EC_GROUP 331 # undef EC_POINT 332 #elif !defined(OPENSSL_HAS_ECC) 333 # undef EC_KEY 334 # undef EC_GROUP 335 # undef EC_POINT 336 #endif 337 338 #endif /* SSHKEY_H */ 339