contrib/hostapd/src/crypto/tls.h

   1 /*
   2  * WPA Supplicant / SSL/TLS interface definition
   3  * Copyright (c) 2004-2007, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Alternatively, this software may be distributed under the terms of BSD
  10  * license.
  11  *
  12  * See README and COPYING for more details.
  13  */
  14
  15 #ifndef TLS_H
  16 #define TLS_H
  17
  18 struct tls_connection;
  19
  20 struct tls_keys {
  21         const u8 *master_key; /* TLS master secret */
  22         size_t master_key_len;
  23         const u8 *client_random;
  24         size_t client_random_len;
  25         const u8 *server_random;
  26         size_t server_random_len;
  27         const u8 *inner_secret; /* TLS/IA inner secret */
  28         size_t inner_secret_len;
  29 };
  30
  31 struct tls_config {
  32         const char *opensc_engine_path;
  33         const char *pkcs11_engine_path;
  34         const char *pkcs11_module_path;
  35 };
  36
  37 #define TLS_CONN_ALLOW_SIGN_RSA_MD5 BIT(0)
  38 #define TLS_CONN_DISABLE_TIME_CHECKS BIT(1)
  39
  40 /**
  41  * struct tls_connection_params - Parameters for TLS connection
  42  * @ca_cert: File or reference name for CA X.509 certificate in PEM or DER
  43  * format
  44  * @ca_cert_blob: ca_cert as inlined data or %NULL if not used
  45  * @ca_cert_blob_len: ca_cert_blob length
  46  * @ca_path: Path to CA certificates (OpenSSL specific)
  47  * @subject_match: String to match in the subject of the peer certificate or
  48  * %NULL to allow all subjects
  49  * @altsubject_match: String to match in the alternative subject of the peer
  50  * certificate or %NULL to allow all alternative subjects
  51  * @client_cert: File or reference name for client X.509 certificate in PEM or
  52  * DER format
  53  * @client_cert_blob: client_cert as inlined data or %NULL if not used
  54  * @client_cert_blob_len: client_cert_blob length
  55  * @private_key: File or reference name for client private key in PEM or DER
  56  * format (traditional format (RSA PRIVATE KEY) or PKCS#8 (PRIVATE KEY)
  57  * @private_key_blob: private_key as inlined data or %NULL if not used
  58  * @private_key_blob_len: private_key_blob length
  59  * @private_key_passwd: Passphrase for decrypted private key, %NULL if no
  60  * passphrase is used.
  61  * @dh_file: File name for DH/DSA data in PEM format, or %NULL if not used
  62  * @dh_blob: dh_file as inlined data or %NULL if not used
  63  * @dh_blob_len: dh_blob length
  64  * @engine: 1 = use engine (e.g., a smartcard) for private key operations
  65  * (this is OpenSSL specific for now)
  66  * @engine_id: engine id string (this is OpenSSL specific for now)
  67  * @ppin: pointer to the pin variable in the configuration
  68  * (this is OpenSSL specific for now)
  69  * @key_id: the private key's id when using engine (this is OpenSSL
  70  * specific for now)
  71  * @cert_id: the certificate's id when using engine
  72  * @ca_cert_id: the CA certificate's id when using engine
  73  * @tls_ia: Whether to enable TLS/IA (for EAP-TTLSv1)
  74  * @flags: Parameter options (TLS_CONN_*)
  75  *
  76  * TLS connection parameters to be configured with tls_connection_set_params()
  77  * and tls_global_set_params().
  78  *
  79  * Certificates and private key can be configured either as a reference name
  80  * (file path or reference to certificate store) or by providing the same data
  81  * as a pointer to the data in memory. Only one option will be used for each
  82  * field.
  83  */
  84 struct tls_connection_params {
  85         const char *ca_cert;
  86         const u8 *ca_cert_blob;
  87         size_t ca_cert_blob_len;
  88         const char *ca_path;
  89         const char *subject_match;
  90         const char *altsubject_match;
  91         const char *client_cert;
  92         const u8 *client_cert_blob;
  93         size_t client_cert_blob_len;
  94         const char *private_key;
  95         const u8 *private_key_blob;
  96         size_t private_key_blob_len;
  97         const char *private_key_passwd;
  98         const char *dh_file;
  99         const u8 *dh_blob;
 100         size_t dh_blob_len;
 101         int tls_ia;
 102
 103         /* OpenSSL specific variables */
 104         int engine;
 105         const char *engine_id;
 106         const char *pin;
 107         const char *key_id;
 108         const char *cert_id;
 109         const char *ca_cert_id;
 110
 111         unsigned int flags;
 112 };
 113
 114
 115 /**
 116  * tls_init - Initialize TLS library
 117  * @conf: Configuration data for TLS library
 118  * Returns: Context data to be used as tls_ctx in calls to other functions,
 119  * or %NULL on failure.
 120  *
 121  * Called once during program startup and once for each RSN pre-authentication
 122  * session. In other words, there can be two concurrent TLS contexts. If global
 123  * library initialization is needed (i.e., one that is shared between both
 124  * authentication types), the TLS library wrapper should maintain a reference
 125  * counter and do global initialization only when moving from 0 to 1 reference.
 126  */
 127 void * tls_init(const struct tls_config *conf);
 128
 129 /**
 130  * tls_deinit - Deinitialize TLS library
 131  * @tls_ctx: TLS context data from tls_init()
 132  *
 133  * Called once during program shutdown and once for each RSN pre-authentication
 134  * session. If global library deinitialization is needed (i.e., one that is
 135  * shared between both authentication types), the TLS library wrapper should
 136  * maintain a reference counter and do global deinitialization only when moving
 137  * from 1 to 0 references.
 138  */
 139 void tls_deinit(void *tls_ctx);
 140
 141 /**
 142  * tls_get_errors - Process pending errors
 143  * @tls_ctx: TLS context data from tls_init()
 144  * Returns: Number of found error, 0 if no errors detected.
 145  *
 146  * Process all pending TLS errors.
 147  */
 148 int tls_get_errors(void *tls_ctx);
 149
 150 /**
 151  * tls_connection_init - Initialize a new TLS connection
 152  * @tls_ctx: TLS context data from tls_init()
 153  * Returns: Connection context data, conn for other function calls
 154  */
 155 struct tls_connection * tls_connection_init(void *tls_ctx);
 156
 157 /**
 158  * tls_connection_deinit - Free TLS connection data
 159  * @tls_ctx: TLS context data from tls_init()
 160  * @conn: Connection context data from tls_connection_init()
 161  *
 162  * Release all resources allocated for TLS connection.
 163  */
 164 void tls_connection_deinit(void *tls_ctx, struct tls_connection *conn);
 165
 166 /**
 167  * tls_connection_established - Has the TLS connection been completed?
 168  * @tls_ctx: TLS context data from tls_init()
 169  * @conn: Connection context data from tls_connection_init()
 170  * Returns: 1 if TLS connection has been completed, 0 if not.
 171  */
 172 int tls_connection_established(void *tls_ctx, struct tls_connection *conn);
 173
 174 /**
 175  * tls_connection_shutdown - Shutdown TLS connection
 176  * @tls_ctx: TLS context data from tls_init()
 177  * @conn: Connection context data from tls_connection_init()
 178  * Returns: 0 on success, -1 on failure
 179  *
 180  * Shutdown current TLS connection without releasing all resources. New
 181  * connection can be started by using the same conn without having to call
 182  * tls_connection_init() or setting certificates etc. again. The new
 183  * connection should try to use session resumption.
 184  */
 185 int tls_connection_shutdown(void *tls_ctx, struct tls_connection *conn);
 186
 187 enum {
 188         TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED = -3,
 189         TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED = -2
 190 };
 191
 192 /**
 193  * tls_connection_set_params - Set TLS connection parameters
 194  * @tls_ctx: TLS context data from tls_init()
 195  * @conn: Connection context data from tls_connection_init()
 196  * @params: Connection parameters
 197  * Returns: 0 on success, -1 on failure,
 198  * TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED (-2) on possible PIN error causing
 199  * PKCS#11 engine failure, or
 200  * TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED (-3) on failure to verify the
 201  * PKCS#11 engine private key.
 202  */
 203 int __must_check
 204 tls_connection_set_params(void *tls_ctx, struct tls_connection *conn,
 205                           const struct tls_connection_params *params);
 206
 207 /**
 208  * tls_global_set_params - Set TLS parameters for all TLS connection
 209  * @tls_ctx: TLS context data from tls_init()
 210  * @params: Global TLS parameters
 211  * Returns: 0 on success, -1 on failure,
 212  * TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED (-2) on possible PIN error causing
 213  * PKCS#11 engine failure, or
 214  * TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED (-3) on failure to verify the
 215  * PKCS#11 engine private key.
 216  */
 217 int __must_check tls_global_set_params(
 218         void *tls_ctx, const struct tls_connection_params *params);
 219
 220 /**
 221  * tls_global_set_verify - Set global certificate verification options
 222  * @tls_ctx: TLS context data from tls_init()
 223  * @check_crl: 0 = do not verify CRLs, 1 = verify CRL for the user certificate,
 224  * 2 = verify CRL for all certificates
 225  * Returns: 0 on success, -1 on failure
 226  */
 227 int __must_check tls_global_set_verify(void *tls_ctx, int check_crl);
 228
 229 /**
 230  * tls_connection_set_verify - Set certificate verification options
 231  * @tls_ctx: TLS context data from tls_init()
 232  * @conn: Connection context data from tls_connection_init()
 233  * @verify_peer: 1 = verify peer certificate
 234  * Returns: 0 on success, -1 on failure
 235  */
 236 int __must_check tls_connection_set_verify(void *tls_ctx,
 237                                            struct tls_connection *conn,
 238                                            int verify_peer);
 239
 240 /**
 241  * tls_connection_set_ia - Set TLS/IA parameters
 242  * @tls_ctx: TLS context data from tls_init()
 243  * @conn: Connection context data from tls_connection_init()
 244  * @tls_ia: 1 = enable TLS/IA
 245  * Returns: 0 on success, -1 on failure
 246  *
 247  * This function is used to configure TLS/IA in server mode where
 248  * tls_connection_set_params() is not used.
 249  */
 250 int __must_check tls_connection_set_ia(void *tls_ctx,
 251                                        struct tls_connection *conn,
 252                                        int tls_ia);
 253
 254 /**
 255  * tls_connection_get_keys - Get master key and random data from TLS connection
 256  * @tls_ctx: TLS context data from tls_init()
 257  * @conn: Connection context data from tls_connection_init()
 258  * @keys: Structure of key/random data (filled on success)
 259  * Returns: 0 on success, -1 on failure
 260  */
 261 int __must_check tls_connection_get_keys(void *tls_ctx,
 262                                          struct tls_connection *conn,
 263                                          struct tls_keys *keys);
 264
 265 /**
 266  * tls_connection_prf - Use TLS-PRF to derive keying material
 267  * @tls_ctx: TLS context data from tls_init()
 268  * @conn: Connection context data from tls_connection_init()
 269  * @label: Label (e.g., description of the key) for PRF
 270  * @server_random_first: seed is 0 = client_random|server_random,
 271  * 1 = server_random|client_random
 272  * @out: Buffer for output data from TLS-PRF
 273  * @out_len: Length of the output buffer
 274  * Returns: 0 on success, -1 on failure
 275  *
 276  * This function is optional to implement if tls_connection_get_keys() provides
 277  * access to master secret and server/client random values. If these values are
 278  * not exported from the TLS library, tls_connection_prf() is required so that
 279  * further keying material can be derived from the master secret. If not
 280  * implemented, the function will still need to be defined, but it can just
 281  * return -1. Example implementation of this function is in tls_prf() function
 282  * when it is called with seed set to client_random|server_random (or
 283  * server_random|client_random).
 284  */
 285 int __must_check  tls_connection_prf(void *tls_ctx,
 286                                      struct tls_connection *conn,
 287                                      const char *label,
 288                                      int server_random_first,
 289                                      u8 *out, size_t out_len);
 290
 291 /**
 292  * tls_connection_handshake - Process TLS handshake (client side)
 293  * @tls_ctx: TLS context data from tls_init()
 294  * @conn: Connection context data from tls_connection_init()
 295  * @in_data: Input data from TLS peer
 296  * @in_len: Input data length
 297  * @out_len: Length of the output buffer.
 298  * @appl_data: Pointer to application data pointer, or %NULL if dropped
 299  * @appl_data_len: Pointer to variable that is set to appl_data length
 300  * Returns: Pointer to output data, %NULL on failure
 301  *
 302  * Caller is responsible for freeing returned output data. If the final
 303  * handshake message includes application data, this is decrypted and
 304  * appl_data (if not %NULL) is set to point this data. Caller is responsible
 305  * for freeing appl_data.
 306  *
 307  * This function is used during TLS handshake. The first call is done with
 308  * in_data == %NULL and the library is expected to return ClientHello packet.
 309  * This packet is then send to the server and a response from server is given
 310  * to TLS library by calling this function again with in_data pointing to the
 311  * TLS message from the server.
 312  *
 313  * If the TLS handshake fails, this function may return %NULL. However, if the
 314  * TLS library has a TLS alert to send out, that should be returned as the
 315  * output data. In this case, tls_connection_get_failed() must return failure
 316  * (> 0).
 317  *
 318  * tls_connection_established() should return 1 once the TLS handshake has been
 319  * completed successfully.
 320  */
 321 u8 * tls_connection_handshake(void *tls_ctx, struct tls_connection *conn,
 322                               const u8 *in_data, size_t in_len,
 323                               size_t *out_len, u8 **appl_data,
 324                               size_t *appl_data_len);
 325
 326 /**
 327  * tls_connection_server_handshake - Process TLS handshake (server side)
 328  * @tls_ctx: TLS context data from tls_init()
 329  * @conn: Connection context data from tls_connection_init()
 330  * @in_data: Input data from TLS peer
 331  * @in_len: Input data length
 332  * @out_len: Length of the output buffer.
 333  * Returns: pointer to output data, %NULL on failure
 334  *
 335  * Caller is responsible for freeing returned output data.
 336  */
 337 u8 * tls_connection_server_handshake(void *tls_ctx,
 338                                      struct tls_connection *conn,
 339                                      const u8 *in_data, size_t in_len,
 340                                      size_t *out_len);
 341
 342 /**
 343  * tls_connection_encrypt - Encrypt data into TLS tunnel
 344  * @tls_ctx: TLS context data from tls_init()
 345  * @conn: Connection context data from tls_connection_init()
 346  * @in_data: Pointer to plaintext data to be encrypted
 347  * @in_len: Input buffer length
 348  * @out_data: Pointer to output buffer (encrypted TLS data)
 349  * @out_len: Maximum out_data length
 350  * Returns: Number of bytes written to out_data, -1 on failure
 351  *
 352  * This function is used after TLS handshake has been completed successfully to
 353  * send data in the encrypted tunnel.
 354  */
 355 int __must_check tls_connection_encrypt(void *tls_ctx,
 356                                         struct tls_connection *conn,
 357                                         const u8 *in_data, size_t in_len,
 358                                         u8 *out_data, size_t out_len);
 359
 360 /**
 361  * tls_connection_decrypt - Decrypt data from TLS tunnel
 362  * @tls_ctx: TLS context data from tls_init()
 363  * @conn: Connection context data from tls_connection_init()
 364  * @in_data: Pointer to input buffer (encrypted TLS data)
 365  * @in_len: Input buffer length
 366  * @out_data: Pointer to output buffer (decrypted data from TLS tunnel)
 367  * @out_len: Maximum out_data length
 368  * Returns: Number of bytes written to out_data, -1 on failure
 369  *
 370  * This function is used after TLS handshake has been completed successfully to
 371  * receive data from the encrypted tunnel.
 372  */
 373 int __must_check tls_connection_decrypt(void *tls_ctx,
 374                                         struct tls_connection *conn,
 375                                         const u8 *in_data, size_t in_len,
 376                                         u8 *out_data, size_t out_len);
 377
 378 /**
 379  * tls_connection_resumed - Was session resumption used
 380  * @tls_ctx: TLS context data from tls_init()
 381  * @conn: Connection context data from tls_connection_init()
 382  * Returns: 1 if current session used session resumption, 0 if not
 383  */
 384 int tls_connection_resumed(void *tls_ctx, struct tls_connection *conn);
 385
 386 enum {
 387         TLS_CIPHER_NONE,
 388         TLS_CIPHER_RC4_SHA /* 0x0005 */,
 389         TLS_CIPHER_AES128_SHA /* 0x002f */,
 390         TLS_CIPHER_RSA_DHE_AES128_SHA /* 0x0031 */,
 391         TLS_CIPHER_ANON_DH_AES128_SHA /* 0x0034 */
 392 };
 393
 394 /**
 395  * tls_connection_set_cipher_list - Configure acceptable cipher suites
 396  * @tls_ctx: TLS context data from tls_init()
 397  * @conn: Connection context data from tls_connection_init()
 398  * @ciphers: Zero (TLS_CIPHER_NONE) terminated list of allowed ciphers
 399  * (TLS_CIPHER_*).
 400  * Returns: 0 on success, -1 on failure
 401  */
 402 int __must_check tls_connection_set_cipher_list(void *tls_ctx,
 403                                                 struct tls_connection *conn,
 404                                                 u8 *ciphers);
 405
 406 /**
 407  * tls_get_cipher - Get current cipher name
 408  * @tls_ctx: TLS context data from tls_init()
 409  * @conn: Connection context data from tls_connection_init()
 410  * @buf: Buffer for the cipher name
 411  * @buflen: buf size
 412  * Returns: 0 on success, -1 on failure
 413  *
 414  * Get the name of the currently used cipher.
 415  */
 416 int __must_check tls_get_cipher(void *tls_ctx, struct tls_connection *conn,
 417                                 char *buf, size_t buflen);
 418
 419 /**
 420  * tls_connection_enable_workaround - Enable TLS workaround options
 421  * @tls_ctx: TLS context data from tls_init()
 422  * @conn: Connection context data from tls_connection_init()
 423  * Returns: 0 on success, -1 on failure
 424  *
 425  * This function is used to enable connection-specific workaround options for
 426  * buffer SSL/TLS implementations.
 427  */
 428 int __must_check tls_connection_enable_workaround(void *tls_ctx,
 429                                                   struct tls_connection *conn);
 430
 431 /**
 432  * tls_connection_client_hello_ext - Set TLS extension for ClientHello
 433  * @tls_ctx: TLS context data from tls_init()
 434  * @conn: Connection context data from tls_connection_init()
 435  * @ext_type: Extension type
 436  * @data: Extension payload (%NULL to remove extension)
 437  * @data_len: Extension payload length
 438  * Returns: 0 on success, -1 on failure
 439  */
 440 int __must_check tls_connection_client_hello_ext(void *tls_ctx,
 441                                                  struct tls_connection *conn,
 442                                                  int ext_type, const u8 *data,
 443                                                  size_t data_len);
 444
 445 /**
 446  * tls_connection_get_failed - Get connection failure status
 447  * @tls_ctx: TLS context data from tls_init()
 448  * @conn: Connection context data from tls_connection_init()
 449  *
 450  * Returns >0 if connection has failed, 0 if not.
 451  */
 452 int tls_connection_get_failed(void *tls_ctx, struct tls_connection *conn);
 453
 454 /**
 455  * tls_connection_get_read_alerts - Get connection read alert status
 456  * @tls_ctx: TLS context data from tls_init()
 457  * @conn: Connection context data from tls_connection_init()
 458  * Returns: Number of times a fatal read (remote end reported error) has
 459  * happened during this connection.
 460  */
 461 int tls_connection_get_read_alerts(void *tls_ctx, struct tls_connection *conn);
 462
 463 /**
 464  * tls_connection_get_write_alerts - Get connection write alert status
 465  * @tls_ctx: TLS context data from tls_init()
 466  * @conn: Connection context data from tls_connection_init()
 467  * Returns: Number of times a fatal write (locally detected error) has happened
 468  * during this connection.
 469  */
 470 int tls_connection_get_write_alerts(void *tls_ctx,
 471                                     struct tls_connection *conn);
 472
 473 /**
 474  * tls_connection_get_keyblock_size - Get TLS key_block size
 475  * @tls_ctx: TLS context data from tls_init()
 476  * @conn: Connection context data from tls_connection_init()
 477  * Returns: Size of the key_block for the negotiated cipher suite or -1 on
 478  * failure
 479  */
 480 int tls_connection_get_keyblock_size(void *tls_ctx,
 481                                      struct tls_connection *conn);
 482
 483 #define TLS_CAPABILITY_IA 0x0001 /* TLS Inner Application (TLS/IA) */
 484 /**
 485  * tls_capabilities - Get supported TLS capabilities
 486  * @tls_ctx: TLS context data from tls_init()
 487  * Returns: Bit field of supported TLS capabilities (TLS_CAPABILITY_*)
 488  */
 489 unsigned int tls_capabilities(void *tls_ctx);
 490
 491 /**
 492  * tls_connection_ia_send_phase_finished - Send a TLS/IA PhaseFinished message
 493  * @tls_ctx: TLS context data from tls_init()
 494  * @conn: Connection context data from tls_connection_init()
 495  * @final: 1 = FinalPhaseFinished, 0 = IntermediatePhaseFinished
 496  * @out_data: Pointer to output buffer (encrypted TLS/IA data)
 497  * @out_len: Maximum out_data length
 498  * Returns: Number of bytes written to out_data on success, -1 on failure
 499  *
 500  * This function is used to send the TLS/IA end phase message, e.g., when the
 501  * EAP server completes EAP-TTLSv1.
 502  */
 503 int __must_check tls_connection_ia_send_phase_finished(
 504         void *tls_ctx, struct tls_connection *conn, int final,
 505         u8 *out_data, size_t out_len);
 506
 507 /**
 508  * tls_connection_ia_final_phase_finished - Has final phase been completed
 509  * @tls_ctx: TLS context data from tls_init()
 510  * @conn: Connection context data from tls_connection_init()
 511  * Returns: 1 if valid FinalPhaseFinished has been received, 0 if not, or -1
 512  * on failure
 513  */
 514 int __must_check tls_connection_ia_final_phase_finished(
 515         void *tls_ctx, struct tls_connection *conn);
 516
 517 /**
 518  * tls_connection_ia_permute_inner_secret - Permute TLS/IA inner secret
 519  * @tls_ctx: TLS context data from tls_init()
 520  * @conn: Connection context data from tls_connection_init()
 521  * @key: Session key material (session_key vectors with 2-octet length), or
 522  * %NULL if no session key was generating in the current phase
 523  * @key_len: Length of session key material
 524  * Returns: 0 on success, -1 on failure
 525  */
 526 int __must_check tls_connection_ia_permute_inner_secret(
 527         void *tls_ctx, struct tls_connection *conn,
 528         const u8 *key, size_t key_len);
 529
 530 typedef int (*tls_session_ticket_cb)
 531 (void *ctx, const u8 *ticket, size_t len, const u8 *client_random,
 532  const u8 *server_random, u8 *master_secret);
 533
 534 int __must_check  tls_connection_set_session_ticket_cb(
 535         void *tls_ctx, struct tls_connection *conn,
 536         tls_session_ticket_cb cb, void *ctx);
 537
 538 #endif /* TLS_H */