1 /* $OpenBSD: sshkey.h,v 1.45 2020/04/08 00:08:46 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 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_RSA */ 127 RSA *rsa; 128 /* KEY_DSA */ 129 DSA *dsa; 130 /* KEY_ECDSA and KEY_ECDSA_SK */ 131 int ecdsa_nid; /* NID of curve */ 132 EC_KEY *ecdsa; 133 /* KEY_ED25519 and KEY_ED25519_SK */ 134 u_char *ed25519_sk; 135 u_char *ed25519_pk; 136 /* KEY_XMSS */ 137 char *xmss_name; 138 char *xmss_filename; /* for state file updates */ 139 void *xmss_state; /* depends on xmss_name, opaque */ 140 u_char *xmss_sk; 141 u_char *xmss_pk; 142 /* KEY_ECDSA_SK and KEY_ED25519_SK */ 143 char *sk_application; 144 uint8_t sk_flags; 145 struct sshbuf *sk_key_handle; 146 struct sshbuf *sk_reserved; 147 /* Certificates */ 148 struct sshkey_cert *cert; 149 /* Private key shielding */ 150 u_char *shielded_private; 151 size_t shielded_len; 152 u_char *shield_prekey; 153 size_t shield_prekey_len; 154 }; 155 156 #define ED25519_SK_SZ crypto_sign_ed25519_SECRETKEYBYTES 157 #define ED25519_PK_SZ crypto_sign_ed25519_PUBLICKEYBYTES 158 159 /* Additional fields contained in signature */ 160 struct sshkey_sig_details { 161 uint32_t sk_counter; /* U2F signature counter */ 162 uint8_t sk_flags; /* U2F signature flags; see ssh-sk.h */ 163 }; 164 165 struct sshkey *sshkey_new(int); 166 void sshkey_free(struct sshkey *); 167 int sshkey_equal_public(const struct sshkey *, 168 const struct sshkey *); 169 int sshkey_equal(const struct sshkey *, const struct sshkey *); 170 char *sshkey_fingerprint(const struct sshkey *, 171 int, enum sshkey_fp_rep); 172 int sshkey_fingerprint_raw(const struct sshkey *k, 173 int, u_char **retp, size_t *lenp); 174 const char *sshkey_type(const struct sshkey *); 175 const char *sshkey_cert_type(const struct sshkey *); 176 int sshkey_format_text(const struct sshkey *, struct sshbuf *); 177 int sshkey_write(const struct sshkey *, FILE *); 178 int sshkey_read(struct sshkey *, char **); 179 u_int sshkey_size(const struct sshkey *); 180 181 int sshkey_generate(int type, u_int bits, struct sshkey **keyp); 182 int sshkey_from_private(const struct sshkey *, struct sshkey **); 183 184 int sshkey_is_shielded(struct sshkey *); 185 int sshkey_shield_private(struct sshkey *); 186 int sshkey_unshield_private(struct sshkey *); 187 188 int sshkey_type_from_name(const char *); 189 int sshkey_is_cert(const struct sshkey *); 190 int sshkey_is_sk(const struct sshkey *); 191 int sshkey_type_is_cert(int); 192 int sshkey_type_plain(int); 193 int sshkey_to_certified(struct sshkey *); 194 int sshkey_drop_cert(struct sshkey *); 195 int sshkey_cert_copy(const struct sshkey *, struct sshkey *); 196 int sshkey_cert_check_authority(const struct sshkey *, int, int, 197 const char *, const char **); 198 size_t sshkey_format_cert_validity(const struct sshkey_cert *, 199 char *, size_t) __attribute__((__bounded__(__string__, 2, 3))); 200 int sshkey_check_cert_sigtype(const struct sshkey *, const char *); 201 202 int sshkey_certify(struct sshkey *, struct sshkey *, 203 const char *, const char *); 204 /* Variant allowing use of a custom signature function (e.g. for ssh-agent) */ 205 typedef int sshkey_certify_signer(struct sshkey *, u_char **, size_t *, 206 const u_char *, size_t, const char *, const char *, u_int, void *); 207 int sshkey_certify_custom(struct sshkey *, struct sshkey *, const char *, 208 const char *, sshkey_certify_signer *, void *); 209 210 int sshkey_ecdsa_nid_from_name(const char *); 211 int sshkey_curve_name_to_nid(const char *); 212 const char * sshkey_curve_nid_to_name(int); 213 u_int sshkey_curve_nid_to_bits(int); 214 int sshkey_ecdsa_bits_to_nid(int); 215 int sshkey_ecdsa_key_to_nid(EC_KEY *); 216 int sshkey_ec_nid_to_hash_alg(int nid); 217 int sshkey_ec_validate_public(const EC_GROUP *, const EC_POINT *); 218 int sshkey_ec_validate_private(const EC_KEY *); 219 const char *sshkey_ssh_name(const struct sshkey *); 220 const char *sshkey_ssh_name_plain(const struct sshkey *); 221 int sshkey_names_valid2(const char *, int); 222 char *sshkey_alg_list(int, int, int, char); 223 224 int sshkey_from_blob(const u_char *, size_t, struct sshkey **); 225 int sshkey_fromb(struct sshbuf *, struct sshkey **); 226 int sshkey_froms(struct sshbuf *, struct sshkey **); 227 int sshkey_to_blob(const struct sshkey *, u_char **, size_t *); 228 int sshkey_to_base64(const struct sshkey *, char **); 229 int sshkey_putb(const struct sshkey *, struct sshbuf *); 230 int sshkey_puts(const struct sshkey *, struct sshbuf *); 231 int sshkey_puts_opts(const struct sshkey *, struct sshbuf *, 232 enum sshkey_serialize_rep); 233 int sshkey_plain_to_blob(const struct sshkey *, u_char **, size_t *); 234 int sshkey_putb_plain(const struct sshkey *, struct sshbuf *); 235 236 int sshkey_sign(struct sshkey *, u_char **, size_t *, 237 const u_char *, size_t, const char *, const char *, u_int); 238 int sshkey_verify(const struct sshkey *, const u_char *, size_t, 239 const u_char *, size_t, const char *, u_int, struct sshkey_sig_details **); 240 int sshkey_check_sigtype(const u_char *, size_t, const char *); 241 const char *sshkey_sigalg_by_name(const char *); 242 int sshkey_get_sigtype(const u_char *, size_t, char **); 243 244 /* for debug */ 245 void sshkey_dump_ec_point(const EC_GROUP *, const EC_POINT *); 246 void sshkey_dump_ec_key(const EC_KEY *); 247 248 /* private key parsing and serialisation */ 249 int sshkey_private_serialize(struct sshkey *key, struct sshbuf *buf); 250 int sshkey_private_serialize_opt(struct sshkey *key, struct sshbuf *buf, 251 enum sshkey_serialize_rep); 252 int sshkey_private_deserialize(struct sshbuf *buf, struct sshkey **keyp); 253 254 /* private key file format parsing and serialisation */ 255 int sshkey_private_to_fileblob(struct sshkey *key, struct sshbuf *blob, 256 const char *passphrase, const char *comment, 257 int format, const char *openssh_format_cipher, int openssh_format_rounds); 258 int sshkey_parse_private_fileblob(struct sshbuf *buffer, 259 const char *passphrase, struct sshkey **keyp, char **commentp); 260 int sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type, 261 const char *passphrase, struct sshkey **keyp, char **commentp); 262 int sshkey_parse_pubkey_from_private_fileblob_type(struct sshbuf *blob, 263 int type, struct sshkey **pubkeyp); 264 265 /* XXX should be internal, but used by ssh-keygen */ 266 int ssh_rsa_complete_crt_parameters(struct sshkey *, const BIGNUM *); 267 268 /* stateful keys (e.g. XMSS) */ 269 #ifdef NO_ATTRIBUTE_ON_PROTOTYPE_ARGS 270 typedef void sshkey_printfn(const char *, ...); 271 #else 272 typedef void sshkey_printfn(const char *, ...) __attribute__((format(printf, 1, 2))); 273 #endif 274 int sshkey_set_filename(struct sshkey *, const char *); 275 int sshkey_enable_maxsign(struct sshkey *, u_int32_t); 276 u_int32_t sshkey_signatures_left(const struct sshkey *); 277 int sshkey_forward_state(const struct sshkey *, u_int32_t, sshkey_printfn *); 278 int sshkey_private_serialize_maxsign(struct sshkey *key, struct sshbuf *buf, 279 u_int32_t maxsign, sshkey_printfn *pr); 280 281 void sshkey_sig_details_free(struct sshkey_sig_details *); 282 283 #ifdef SSHKEY_INTERNAL 284 int ssh_rsa_sign(const struct sshkey *key, 285 u_char **sigp, size_t *lenp, const u_char *data, size_t datalen, 286 const char *ident); 287 int ssh_rsa_verify(const struct sshkey *key, 288 const u_char *sig, size_t siglen, const u_char *data, size_t datalen, 289 const char *alg); 290 int ssh_dss_sign(const struct sshkey *key, u_char **sigp, size_t *lenp, 291 const u_char *data, size_t datalen, u_int compat); 292 int ssh_dss_verify(const struct sshkey *key, 293 const u_char *signature, size_t signaturelen, 294 const u_char *data, size_t datalen, u_int compat); 295 int ssh_ecdsa_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_ecdsa_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_ecdsa_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_ed25519_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_ed25519_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 int ssh_ed25519_sk_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 struct sshkey_sig_details **detailsp); 313 int ssh_xmss_sign(const struct sshkey *key, u_char **sigp, size_t *lenp, 314 const u_char *data, size_t datalen, u_int compat); 315 int ssh_xmss_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 #endif 319 320 #if !defined(WITH_OPENSSL) 321 # undef RSA 322 # undef DSA 323 # undef EC_KEY 324 # undef EC_GROUP 325 # undef EC_POINT 326 #elif !defined(OPENSSL_HAS_ECC) 327 # undef EC_KEY 328 # undef EC_GROUP 329 # undef EC_POINT 330 #endif 331 332 #endif /* SSHKEY_H */ 333