1 /* $OpenBSD: sshkey.h,v 1.44 2019/12/30 09:23:28 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 *); 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 *, u_int, void *); 201 int sshkey_certify_custom(struct sshkey *, struct sshkey *, const char *, 202 const char *, sshkey_certify_signer *, void *); 203 204 int sshkey_ecdsa_nid_from_name(const char *); 205 int sshkey_curve_name_to_nid(const char *); 206 const char * sshkey_curve_nid_to_name(int); 207 u_int sshkey_curve_nid_to_bits(int); 208 int sshkey_ecdsa_bits_to_nid(int); 209 int sshkey_ecdsa_key_to_nid(EC_KEY *); 210 int sshkey_ec_nid_to_hash_alg(int nid); 211 int sshkey_ec_validate_public(const EC_GROUP *, const EC_POINT *); 212 int sshkey_ec_validate_private(const EC_KEY *); 213 const char *sshkey_ssh_name(const struct sshkey *); 214 const char *sshkey_ssh_name_plain(const struct sshkey *); 215 int sshkey_names_valid2(const char *, int); 216 char *sshkey_alg_list(int, int, int, char); 217 218 int sshkey_from_blob(const u_char *, size_t, struct sshkey **); 219 int sshkey_fromb(struct sshbuf *, struct sshkey **); 220 int sshkey_froms(struct sshbuf *, struct sshkey **); 221 int sshkey_to_blob(const struct sshkey *, u_char **, size_t *); 222 int sshkey_to_base64(const struct sshkey *, char **); 223 int sshkey_putb(const struct sshkey *, struct sshbuf *); 224 int sshkey_puts(const struct sshkey *, struct sshbuf *); 225 int sshkey_puts_opts(const struct sshkey *, struct sshbuf *, 226 enum sshkey_serialize_rep); 227 int sshkey_plain_to_blob(const struct sshkey *, u_char **, size_t *); 228 int sshkey_putb_plain(const struct sshkey *, struct sshbuf *); 229 230 int sshkey_sign(struct sshkey *, u_char **, size_t *, 231 const u_char *, size_t, const char *, const char *, u_int); 232 int sshkey_verify(const struct sshkey *, const u_char *, size_t, 233 const u_char *, size_t, const char *, u_int, struct sshkey_sig_details **); 234 int sshkey_check_sigtype(const u_char *, size_t, const char *); 235 const char *sshkey_sigalg_by_name(const char *); 236 int sshkey_get_sigtype(const u_char *, size_t, char **); 237 238 /* for debug */ 239 void sshkey_dump_ec_point(const EC_GROUP *, const EC_POINT *); 240 void sshkey_dump_ec_key(const EC_KEY *); 241 242 /* private key parsing and serialisation */ 243 int sshkey_private_serialize(struct sshkey *key, struct sshbuf *buf); 244 int sshkey_private_serialize_opt(struct sshkey *key, struct sshbuf *buf, 245 enum sshkey_serialize_rep); 246 int sshkey_private_deserialize(struct sshbuf *buf, struct sshkey **keyp); 247 248 /* private key file format parsing and serialisation */ 249 int sshkey_private_to_fileblob(struct sshkey *key, struct sshbuf *blob, 250 const char *passphrase, const char *comment, 251 int format, const char *openssh_format_cipher, int openssh_format_rounds); 252 int sshkey_parse_private_fileblob(struct sshbuf *buffer, 253 const char *passphrase, struct sshkey **keyp, char **commentp); 254 int sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type, 255 const char *passphrase, struct sshkey **keyp, char **commentp); 256 257 /* XXX should be internal, but used by ssh-keygen */ 258 int ssh_rsa_complete_crt_parameters(struct sshkey *, const BIGNUM *); 259 260 /* stateful keys (e.g. XMSS) */ 261 typedef void sshkey_printfn(const char *, ...) __attribute__((format(printf, 1, 2))); 262 int sshkey_set_filename(struct sshkey *, const char *); 263 int sshkey_enable_maxsign(struct sshkey *, u_int32_t); 264 u_int32_t sshkey_signatures_left(const struct sshkey *); 265 int sshkey_forward_state(const struct sshkey *, u_int32_t, sshkey_printfn *); 266 int sshkey_private_serialize_maxsign(struct sshkey *key, struct sshbuf *buf, 267 u_int32_t maxsign, sshkey_printfn *pr); 268 269 void sshkey_sig_details_free(struct sshkey_sig_details *); 270 271 #ifdef SSHKEY_INTERNAL 272 int ssh_rsa_sign(const struct sshkey *key, 273 u_char **sigp, size_t *lenp, const u_char *data, size_t datalen, 274 const char *ident); 275 int ssh_rsa_verify(const struct sshkey *key, 276 const u_char *sig, size_t siglen, const u_char *data, size_t datalen, 277 const char *alg); 278 int ssh_dss_sign(const struct sshkey *key, u_char **sigp, size_t *lenp, 279 const u_char *data, size_t datalen, u_int compat); 280 int ssh_dss_verify(const struct sshkey *key, 281 const u_char *signature, size_t signaturelen, 282 const u_char *data, size_t datalen, u_int compat); 283 int ssh_ecdsa_sign(const struct sshkey *key, u_char **sigp, size_t *lenp, 284 const u_char *data, size_t datalen, u_int compat); 285 int ssh_ecdsa_verify(const struct sshkey *key, 286 const u_char *signature, size_t signaturelen, 287 const u_char *data, size_t datalen, u_int compat); 288 int ssh_ecdsa_sk_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 struct sshkey_sig_details **detailsp); 292 int ssh_ed25519_sign(const struct sshkey *key, u_char **sigp, size_t *lenp, 293 const u_char *data, size_t datalen, u_int compat); 294 int ssh_ed25519_verify(const struct sshkey *key, 295 const u_char *signature, size_t signaturelen, 296 const u_char *data, size_t datalen, u_int compat); 297 int ssh_ed25519_sk_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 struct sshkey_sig_details **detailsp); 301 int ssh_xmss_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_xmss_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 #endif 307 308 #ifndef WITH_OPENSSL 309 #undef RSA 310 #undef DSA 311 #undef EC_KEY 312 #undef EC_GROUP 313 #undef EC_POINT 314 #endif /* WITH_OPENSSL */ 315 316 #endif /* SSHKEY_H */ 317