src/crypto/tls.h

   1 /*
   2  * SSL/TLS interface definition
   3  * Copyright (c) 2004-2013, Jouni Malinen <j@w1.fi>
   4  *
   5  * This software may be distributed under the terms of the BSD license.
   6  * See README for more details.
   7  */
   8
   9 #ifndef TLS_H
  10 #define TLS_H
  11
  12 struct tls_connection;
  13
  14 struct tls_keys {
  15         const u8 *master_key; /* TLS master secret */
  16         size_t master_key_len;
  17         const u8 *client_random;
  18         size_t client_random_len;
  19         const u8 *server_random;
  20         size_t server_random_len;
  21 };
  22
  23 enum tls_event {
  24         TLS_CERT_CHAIN_SUCCESS,
  25         TLS_CERT_CHAIN_FAILURE,
  26         TLS_PEER_CERTIFICATE,
  27         TLS_ALERT
  28 };
  29
  30 /*
  31  * Note: These are used as identifier with external programs and as such, the
  32  * values must not be changed.
  33  */
  34 enum tls_fail_reason {
  35         TLS_FAIL_UNSPECIFIED = 0,
  36         TLS_FAIL_UNTRUSTED = 1,
  37         TLS_FAIL_REVOKED = 2,
  38         TLS_FAIL_NOT_YET_VALID = 3,
  39         TLS_FAIL_EXPIRED = 4,
  40         TLS_FAIL_SUBJECT_MISMATCH = 5,
  41         TLS_FAIL_ALTSUBJECT_MISMATCH = 6,
  42         TLS_FAIL_BAD_CERTIFICATE = 7,
  43         TLS_FAIL_SERVER_CHAIN_PROBE = 8,
  44         TLS_FAIL_DOMAIN_SUFFIX_MISMATCH = 9
  45 };
  46
  47 union tls_event_data {
  48         struct {
  49                 int depth;
  50                 const char *subject;
  51                 enum tls_fail_reason reason;
  52                 const char *reason_txt;
  53                 const struct wpabuf *cert;
  54         } cert_fail;
  55
  56         struct {
  57                 int depth;
  58                 const char *subject;
  59                 const struct wpabuf *cert;
  60                 const u8 *hash;
  61                 size_t hash_len;
  62         } peer_cert;
  63
  64         struct {
  65                 int is_local;
  66                 const char *type;
  67                 const char *description;
  68         } alert;
  69 };
  70
  71 struct tls_config {
  72         const char *opensc_engine_path;
  73         const char *pkcs11_engine_path;
  74         const char *pkcs11_module_path;
  75         int fips_mode;
  76         int cert_in_cb;
  77
  78         void (*event_cb)(void *ctx, enum tls_event ev,
  79                          union tls_event_data *data);
  80         void *cb_ctx;
  81 };
  82
  83 #define TLS_CONN_ALLOW_SIGN_RSA_MD5 BIT(0)
  84 #define TLS_CONN_DISABLE_TIME_CHECKS BIT(1)
  85 #define TLS_CONN_DISABLE_SESSION_TICKET BIT(2)
  86 #define TLS_CONN_REQUEST_OCSP BIT(3)
  87 #define TLS_CONN_REQUIRE_OCSP BIT(4)
  88 #define TLS_CONN_DISABLE_TLSv1_1 BIT(5)
  89 #define TLS_CONN_DISABLE_TLSv1_2 BIT(6)
  90
  91 /**
  92  * struct tls_connection_params - Parameters for TLS connection
  93  * @ca_cert: File or reference name for CA X.509 certificate in PEM or DER
  94  * format
  95  * @ca_cert_blob: ca_cert as inlined data or %NULL if not used
  96  * @ca_cert_blob_len: ca_cert_blob length
  97  * @ca_path: Path to CA certificates (OpenSSL specific)
  98  * @subject_match: String to match in the subject of the peer certificate or
  99  * %NULL to allow all subjects
 100  * @altsubject_match: String to match in the alternative subject of the peer
 101  * certificate or %NULL to allow all alternative subjects
 102  * @suffix_match: String to suffix match in the dNSName or CN of the peer
 103  * certificate or %NULL to allow all domain names
 104  * @client_cert: File or reference name for client X.509 certificate in PEM or
 105  * DER format
 106  * @client_cert_blob: client_cert as inlined data or %NULL if not used
 107  * @client_cert_blob_len: client_cert_blob length
 108  * @private_key: File or reference name for client private key in PEM or DER
 109  * format (traditional format (RSA PRIVATE KEY) or PKCS#8 (PRIVATE KEY)
 110  * @private_key_blob: private_key as inlined data or %NULL if not used
 111  * @private_key_blob_len: private_key_blob length
 112  * @private_key_passwd: Passphrase for decrypted private key, %NULL if no
 113  * passphrase is used.
 114  * @dh_file: File name for DH/DSA data in PEM format, or %NULL if not used
 115  * @dh_blob: dh_file as inlined data or %NULL if not used
 116  * @dh_blob_len: dh_blob length
 117  * @engine: 1 = use engine (e.g., a smartcard) for private key operations
 118  * (this is OpenSSL specific for now)
 119  * @engine_id: engine id string (this is OpenSSL specific for now)
 120  * @ppin: pointer to the pin variable in the configuration
 121  * (this is OpenSSL specific for now)
 122  * @key_id: the private key's id when using engine (this is OpenSSL
 123  * specific for now)
 124  * @cert_id: the certificate's id when using engine
 125  * @ca_cert_id: the CA certificate's id when using engine
 126  * @flags: Parameter options (TLS_CONN_*)
 127  * @ocsp_stapling_response: DER encoded file with cached OCSP stapling response
 128  *      or %NULL if OCSP is not enabled
 129  *
 130  * TLS connection parameters to be configured with tls_connection_set_params()
 131  * and tls_global_set_params().
 132  *
 133  * Certificates and private key can be configured either as a reference name
 134  * (file path or reference to certificate store) or by providing the same data
 135  * as a pointer to the data in memory. Only one option will be used for each
 136  * field.
 137  */
 138 struct tls_connection_params {
 139         const char *ca_cert;
 140         const u8 *ca_cert_blob;
 141         size_t ca_cert_blob_len;
 142         const char *ca_path;
 143         const char *subject_match;
 144         const char *altsubject_match;
 145         const char *suffix_match;
 146         const char *client_cert;
 147         const u8 *client_cert_blob;
 148         size_t client_cert_blob_len;
 149         const char *private_key;
 150         const u8 *private_key_blob;
 151         size_t private_key_blob_len;
 152         const char *private_key_passwd;
 153         const char *dh_file;
 154         const u8 *dh_blob;
 155         size_t dh_blob_len;
 156
 157         /* OpenSSL specific variables */
 158         int engine;
 159         const char *engine_id;
 160         const char *pin;
 161         const char *key_id;
 162         const char *cert_id;
 163         const char *ca_cert_id;
 164
 165         unsigned int flags;
 166         const char *ocsp_stapling_response;
 167 };
 168
 169
 170 /**
 171  * tls_init - Initialize TLS library
 172  * @conf: Configuration data for TLS library
 173  * Returns: Context data to be used as tls_ctx in calls to other functions,
 174  * or %NULL on failure.
 175  *
 176  * Called once during program startup and once for each RSN pre-authentication
 177  * session. In other words, there can be two concurrent TLS contexts. If global
 178  * library initialization is needed (i.e., one that is shared between both
 179  * authentication types), the TLS library wrapper should maintain a reference
 180  * counter and do global initialization only when moving from 0 to 1 reference.
 181  */
 182 void * tls_init(const struct tls_config *conf);
 183
 184 /**
 185  * tls_deinit - Deinitialize TLS library
 186  * @tls_ctx: TLS context data from tls_init()
 187  *
 188  * Called once during program shutdown and once for each RSN pre-authentication
 189  * session. If global library deinitialization is needed (i.e., one that is
 190  * shared between both authentication types), the TLS library wrapper should
 191  * maintain a reference counter and do global deinitialization only when moving
 192  * from 1 to 0 references.
 193  */
 194 void tls_deinit(void *tls_ctx);
 195
 196 /**
 197  * tls_get_errors - Process pending errors
 198  * @tls_ctx: TLS context data from tls_init()
 199  * Returns: Number of found error, 0 if no errors detected.
 200  *
 201  * Process all pending TLS errors.
 202  */
 203 int tls_get_errors(void *tls_ctx);
 204
 205 /**
 206  * tls_connection_init - Initialize a new TLS connection
 207  * @tls_ctx: TLS context data from tls_init()
 208  * Returns: Connection context data, conn for other function calls
 209  */
 210 struct tls_connection * tls_connection_init(void *tls_ctx);
 211
 212 /**
 213  * tls_connection_deinit - Free TLS connection data
 214  * @tls_ctx: TLS context data from tls_init()
 215  * @conn: Connection context data from tls_connection_init()
 216  *
 217  * Release all resources allocated for TLS connection.
 218  */
 219 void tls_connection_deinit(void *tls_ctx, struct tls_connection *conn);
 220
 221 /**
 222  * tls_connection_established - Has the TLS connection been completed?
 223  * @tls_ctx: TLS context data from tls_init()
 224  * @conn: Connection context data from tls_connection_init()
 225  * Returns: 1 if TLS connection has been completed, 0 if not.
 226  */
 227 int tls_connection_established(void *tls_ctx, struct tls_connection *conn);
 228
 229 /**
 230  * tls_connection_shutdown - Shutdown TLS connection
 231  * @tls_ctx: TLS context data from tls_init()
 232  * @conn: Connection context data from tls_connection_init()
 233  * Returns: 0 on success, -1 on failure
 234  *
 235  * Shutdown current TLS connection without releasing all resources. New
 236  * connection can be started by using the same conn without having to call
 237  * tls_connection_init() or setting certificates etc. again. The new
 238  * connection should try to use session resumption.
 239  */
 240 int tls_connection_shutdown(void *tls_ctx, struct tls_connection *conn);
 241
 242 enum {
 243         TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED = -3,
 244         TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED = -2
 245 };
 246
 247 /**
 248  * tls_connection_set_params - Set TLS connection parameters
 249  * @tls_ctx: TLS context data from tls_init()
 250  * @conn: Connection context data from tls_connection_init()
 251  * @params: Connection parameters
 252  * Returns: 0 on success, -1 on failure,
 253  * TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED (-2) on possible PIN error causing
 254  * PKCS#11 engine failure, or
 255  * TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED (-3) on failure to verify the
 256  * PKCS#11 engine private key.
 257  */
 258 int __must_check
 259 tls_connection_set_params(void *tls_ctx, struct tls_connection *conn,
 260                           const struct tls_connection_params *params);
 261
 262 /**
 263  * tls_global_set_params - Set TLS parameters for all TLS connection
 264  * @tls_ctx: TLS context data from tls_init()
 265  * @params: Global TLS parameters
 266  * Returns: 0 on success, -1 on failure,
 267  * TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED (-2) on possible PIN error causing
 268  * PKCS#11 engine failure, or
 269  * TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED (-3) on failure to verify the
 270  * PKCS#11 engine private key.
 271  */
 272 int __must_check tls_global_set_params(
 273         void *tls_ctx, const struct tls_connection_params *params);
 274
 275 /**
 276  * tls_global_set_verify - Set global certificate verification options
 277  * @tls_ctx: TLS context data from tls_init()
 278  * @check_crl: 0 = do not verify CRLs, 1 = verify CRL for the user certificate,
 279  * 2 = verify CRL for all certificates
 280  * Returns: 0 on success, -1 on failure
 281  */
 282 int __must_check tls_global_set_verify(void *tls_ctx, int check_crl);
 283
 284 /**
 285  * tls_connection_set_verify - Set certificate verification options
 286  * @tls_ctx: TLS context data from tls_init()
 287  * @conn: Connection context data from tls_connection_init()
 288  * @verify_peer: 1 = verify peer certificate
 289  * Returns: 0 on success, -1 on failure
 290  */
 291 int __must_check tls_connection_set_verify(void *tls_ctx,
 292                                            struct tls_connection *conn,
 293                                            int verify_peer);
 294
 295 /**
 296  * tls_connection_get_keys - Get master key and random data from TLS connection
 297  * @tls_ctx: TLS context data from tls_init()
 298  * @conn: Connection context data from tls_connection_init()
 299  * @keys: Structure of key/random data (filled on success)
 300  * Returns: 0 on success, -1 on failure
 301  */
 302 int __must_check tls_connection_get_keys(void *tls_ctx,
 303                                          struct tls_connection *conn,
 304                                          struct tls_keys *keys);
 305
 306 /**
 307  * tls_connection_prf - Use TLS-PRF to derive keying material
 308  * @tls_ctx: TLS context data from tls_init()
 309  * @conn: Connection context data from tls_connection_init()
 310  * @label: Label (e.g., description of the key) for PRF
 311  * @server_random_first: seed is 0 = client_random|server_random,
 312  * 1 = server_random|client_random
 313  * @out: Buffer for output data from TLS-PRF
 314  * @out_len: Length of the output buffer
 315  * Returns: 0 on success, -1 on failure
 316  *
 317  * This function is optional to implement if tls_connection_get_keys() provides
 318  * access to master secret and server/client random values. If these values are
 319  * not exported from the TLS library, tls_connection_prf() is required so that
 320  * further keying material can be derived from the master secret. If not
 321  * implemented, the function will still need to be defined, but it can just
 322  * return -1. Example implementation of this function is in tls_prf_sha1_md5()
 323  * when it is called with seed set to client_random|server_random (or
 324  * server_random|client_random).
 325  */
 326 int __must_check  tls_connection_prf(void *tls_ctx,
 327                                      struct tls_connection *conn,
 328                                      const char *label,
 329                                      int server_random_first,
 330                                      u8 *out, size_t out_len);
 331
 332 /**
 333  * tls_connection_handshake - Process TLS handshake (client side)
 334  * @tls_ctx: TLS context data from tls_init()
 335  * @conn: Connection context data from tls_connection_init()
 336  * @in_data: Input data from TLS server
 337  * @appl_data: Pointer to application data pointer, or %NULL if dropped
 338  * Returns: Output data, %NULL on failure
 339  *
 340  * The caller is responsible for freeing the returned output data. If the final
 341  * handshake message includes application data, this is decrypted and
 342  * appl_data (if not %NULL) is set to point this data. The caller is
 343  * responsible for freeing appl_data.
 344  *
 345  * This function is used during TLS handshake. The first call is done with
 346  * in_data == %NULL and the library is expected to return ClientHello packet.
 347  * This packet is then send to the server and a response from server is given
 348  * to TLS library by calling this function again with in_data pointing to the
 349  * TLS message from the server.
 350  *
 351  * If the TLS handshake fails, this function may return %NULL. However, if the
 352  * TLS library has a TLS alert to send out, that should be returned as the
 353  * output data. In this case, tls_connection_get_failed() must return failure
 354  * (> 0).
 355  *
 356  * tls_connection_established() should return 1 once the TLS handshake has been
 357  * completed successfully.
 358  */
 359 struct wpabuf * tls_connection_handshake(void *tls_ctx,
 360                                          struct tls_connection *conn,
 361                                          const struct wpabuf *in_data,
 362                                          struct wpabuf **appl_data);
 363
 364 struct wpabuf * tls_connection_handshake2(void *tls_ctx,
 365                                           struct tls_connection *conn,
 366                                           const struct wpabuf *in_data,
 367                                           struct wpabuf **appl_data,
 368                                           int *more_data_needed);
 369
 370 /**
 371  * tls_connection_server_handshake - Process TLS handshake (server side)
 372  * @tls_ctx: TLS context data from tls_init()
 373  * @conn: Connection context data from tls_connection_init()
 374  * @in_data: Input data from TLS peer
 375  * @appl_data: Pointer to application data pointer, or %NULL if dropped
 376  * Returns: Output data, %NULL on failure
 377  *
 378  * The caller is responsible for freeing the returned output data.
 379  */
 380 struct wpabuf * tls_connection_server_handshake(void *tls_ctx,
 381                                                 struct tls_connection *conn,
 382                                                 const struct wpabuf *in_data,
 383                                                 struct wpabuf **appl_data);
 384
 385 /**
 386  * tls_connection_encrypt - Encrypt data into TLS tunnel
 387  * @tls_ctx: TLS context data from tls_init()
 388  * @conn: Connection context data from tls_connection_init()
 389  * @in_data: Plaintext data to be encrypted
 390  * Returns: Encrypted TLS data or %NULL on failure
 391  *
 392  * This function is used after TLS handshake has been completed successfully to
 393  * send data in the encrypted tunnel. The caller is responsible for freeing the
 394  * returned output data.
 395  */
 396 struct wpabuf * tls_connection_encrypt(void *tls_ctx,
 397                                        struct tls_connection *conn,
 398                                        const struct wpabuf *in_data);
 399
 400 /**
 401  * tls_connection_decrypt - Decrypt data from TLS tunnel
 402  * @tls_ctx: TLS context data from tls_init()
 403  * @conn: Connection context data from tls_connection_init()
 404  * @in_data: Encrypted TLS data
 405  * Returns: Decrypted TLS data or %NULL on failure
 406  *
 407  * This function is used after TLS handshake has been completed successfully to
 408  * receive data from the encrypted tunnel. The caller is responsible for
 409  * freeing the returned output data.
 410  */
 411 struct wpabuf * tls_connection_decrypt(void *tls_ctx,
 412                                        struct tls_connection *conn,
 413                                        const struct wpabuf *in_data);
 414
 415 struct wpabuf * tls_connection_decrypt2(void *tls_ctx,
 416                                         struct tls_connection *conn,
 417                                         const struct wpabuf *in_data,
 418                                         int *more_data_needed);
 419
 420 /**
 421  * tls_connection_resumed - Was session resumption used
 422  * @tls_ctx: TLS context data from tls_init()
 423  * @conn: Connection context data from tls_connection_init()
 424  * Returns: 1 if current session used session resumption, 0 if not
 425  */
 426 int tls_connection_resumed(void *tls_ctx, struct tls_connection *conn);
 427
 428 enum {
 429         TLS_CIPHER_NONE,
 430         TLS_CIPHER_RC4_SHA /* 0x0005 */,
 431         TLS_CIPHER_AES128_SHA /* 0x002f */,
 432         TLS_CIPHER_RSA_DHE_AES128_SHA /* 0x0031 */,
 433         TLS_CIPHER_ANON_DH_AES128_SHA /* 0x0034 */
 434 };
 435
 436 /**
 437  * tls_connection_set_cipher_list - Configure acceptable cipher suites
 438  * @tls_ctx: TLS context data from tls_init()
 439  * @conn: Connection context data from tls_connection_init()
 440  * @ciphers: Zero (TLS_CIPHER_NONE) terminated list of allowed ciphers
 441  * (TLS_CIPHER_*).
 442  * Returns: 0 on success, -1 on failure
 443  */
 444 int __must_check tls_connection_set_cipher_list(void *tls_ctx,
 445                                                 struct tls_connection *conn,
 446                                                 u8 *ciphers);
 447
 448 /**
 449  * tls_get_cipher - Get current cipher name
 450  * @tls_ctx: TLS context data from tls_init()
 451  * @conn: Connection context data from tls_connection_init()
 452  * @buf: Buffer for the cipher name
 453  * @buflen: buf size
 454  * Returns: 0 on success, -1 on failure
 455  *
 456  * Get the name of the currently used cipher.
 457  */
 458 int __must_check tls_get_cipher(void *tls_ctx, struct tls_connection *conn,
 459                                 char *buf, size_t buflen);
 460
 461 /**
 462  * tls_connection_enable_workaround - Enable TLS workaround options
 463  * @tls_ctx: TLS context data from tls_init()
 464  * @conn: Connection context data from tls_connection_init()
 465  * Returns: 0 on success, -1 on failure
 466  *
 467  * This function is used to enable connection-specific workaround options for
 468  * buffer SSL/TLS implementations.
 469  */
 470 int __must_check tls_connection_enable_workaround(void *tls_ctx,
 471                                                   struct tls_connection *conn);
 472
 473 /**
 474  * tls_connection_client_hello_ext - Set TLS extension for ClientHello
 475  * @tls_ctx: TLS context data from tls_init()
 476  * @conn: Connection context data from tls_connection_init()
 477  * @ext_type: Extension type
 478  * @data: Extension payload (%NULL to remove extension)
 479  * @data_len: Extension payload length
 480  * Returns: 0 on success, -1 on failure
 481  */
 482 int __must_check tls_connection_client_hello_ext(void *tls_ctx,
 483                                                  struct tls_connection *conn,
 484                                                  int ext_type, const u8 *data,
 485                                                  size_t data_len);
 486
 487 /**
 488  * tls_connection_get_failed - Get connection failure status
 489  * @tls_ctx: TLS context data from tls_init()
 490  * @conn: Connection context data from tls_connection_init()
 491  *
 492  * Returns >0 if connection has failed, 0 if not.
 493  */
 494 int tls_connection_get_failed(void *tls_ctx, struct tls_connection *conn);
 495
 496 /**
 497  * tls_connection_get_read_alerts - Get connection read alert status
 498  * @tls_ctx: TLS context data from tls_init()
 499  * @conn: Connection context data from tls_connection_init()
 500  * Returns: Number of times a fatal read (remote end reported error) has
 501  * happened during this connection.
 502  */
 503 int tls_connection_get_read_alerts(void *tls_ctx, struct tls_connection *conn);
 504
 505 /**
 506  * tls_connection_get_write_alerts - Get connection write alert status
 507  * @tls_ctx: TLS context data from tls_init()
 508  * @conn: Connection context data from tls_connection_init()
 509  * Returns: Number of times a fatal write (locally detected error) has happened
 510  * during this connection.
 511  */
 512 int tls_connection_get_write_alerts(void *tls_ctx,
 513                                     struct tls_connection *conn);
 514
 515 /**
 516  * tls_connection_get_keyblock_size - Get TLS key_block size
 517  * @tls_ctx: TLS context data from tls_init()
 518  * @conn: Connection context data from tls_connection_init()
 519  * Returns: Size of the key_block for the negotiated cipher suite or -1 on
 520  * failure
 521  */
 522 int tls_connection_get_keyblock_size(void *tls_ctx,
 523                                      struct tls_connection *conn);
 524
 525 /**
 526  * tls_capabilities - Get supported TLS capabilities
 527  * @tls_ctx: TLS context data from tls_init()
 528  * Returns: Bit field of supported TLS capabilities (TLS_CAPABILITY_*)
 529  */
 530 unsigned int tls_capabilities(void *tls_ctx);
 531
 532 typedef int (*tls_session_ticket_cb)
 533 (void *ctx, const u8 *ticket, size_t len, const u8 *client_random,
 534  const u8 *server_random, u8 *master_secret);
 535
 536 int __must_check  tls_connection_set_session_ticket_cb(
 537         void *tls_ctx, struct tls_connection *conn,
 538         tls_session_ticket_cb cb, void *ctx);
 539
 540 void tls_connection_set_log_cb(struct tls_connection *conn,
 541                                void (*log_cb)(void *ctx, const char *msg),
 542                                void *ctx);
 543
 544 #define TLS_BREAK_VERIFY_DATA BIT(0)
 545 #define TLS_BREAK_SRV_KEY_X_HASH BIT(1)
 546 #define TLS_BREAK_SRV_KEY_X_SIGNATURE BIT(2)
 547 #define TLS_DHE_PRIME_511B BIT(3)
 548 #define TLS_DHE_PRIME_767B BIT(4)
 549 #define TLS_DHE_PRIME_15 BIT(5)
 550 #define TLS_DHE_PRIME_58B BIT(6)
 551 #define TLS_DHE_NON_PRIME BIT(7)
 552
 553 void tls_connection_set_test_flags(struct tls_connection *conn, u32 flags);
 554
 555 #endif /* TLS_H */