ssl_internal.h 18 KB

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  1. /**
  2. * \file ssl_ticket.h
  3. *
  4. * \brief Internal functions shared by the SSL modules
  5. *
  6. * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
  7. * SPDX-License-Identifier: Apache-2.0
  8. *
  9. * Licensed under the Apache License, Version 2.0 (the "License"); you may
  10. * not use this file except in compliance with the License.
  11. * You may obtain a copy of the License at
  12. *
  13. * http://www.apache.org/licenses/LICENSE-2.0
  14. *
  15. * Unless required by applicable law or agreed to in writing, software
  16. * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  17. * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  18. * See the License for the specific language governing permissions and
  19. * limitations under the License.
  20. *
  21. * This file is part of mbed TLS (https://tls.mbed.org)
  22. */
  23. #ifndef MBEDTLS_SSL_INTERNAL_H
  24. #define MBEDTLS_SSL_INTERNAL_H
  25. #include "ssl.h"
  26. #if defined(MBEDTLS_MD5_C)
  27. #include "md5.h"
  28. #endif
  29. #if defined(MBEDTLS_SHA1_C)
  30. #include "sha1.h"
  31. #endif
  32. #if defined(MBEDTLS_SHA256_C)
  33. #include "sha256.h"
  34. #endif
  35. #if defined(MBEDTLS_SHA512_C)
  36. #include "sha512.h"
  37. #endif
  38. #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
  39. #include "ecjpake.h"
  40. #endif
  41. #if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
  42. !defined(inline) && !defined(__cplusplus)
  43. #define inline __inline
  44. #endif
  45. /* Determine minimum supported version */
  46. #define MBEDTLS_SSL_MIN_MAJOR_VERSION MBEDTLS_SSL_MAJOR_VERSION_3
  47. #if defined(MBEDTLS_SSL_PROTO_SSL3)
  48. #define MBEDTLS_SSL_MIN_MINOR_VERSION MBEDTLS_SSL_MINOR_VERSION_0
  49. #else
  50. #if defined(MBEDTLS_SSL_PROTO_TLS1)
  51. #define MBEDTLS_SSL_MIN_MINOR_VERSION MBEDTLS_SSL_MINOR_VERSION_1
  52. #else
  53. #if defined(MBEDTLS_SSL_PROTO_TLS1_1)
  54. #define MBEDTLS_SSL_MIN_MINOR_VERSION MBEDTLS_SSL_MINOR_VERSION_2
  55. #else
  56. #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
  57. #define MBEDTLS_SSL_MIN_MINOR_VERSION MBEDTLS_SSL_MINOR_VERSION_3
  58. #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
  59. #endif /* MBEDTLS_SSL_PROTO_TLS1_1 */
  60. #endif /* MBEDTLS_SSL_PROTO_TLS1 */
  61. #endif /* MBEDTLS_SSL_PROTO_SSL3 */
  62. /* Determine maximum supported version */
  63. #define MBEDTLS_SSL_MAX_MAJOR_VERSION MBEDTLS_SSL_MAJOR_VERSION_3
  64. #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
  65. #define MBEDTLS_SSL_MAX_MINOR_VERSION MBEDTLS_SSL_MINOR_VERSION_3
  66. #else
  67. #if defined(MBEDTLS_SSL_PROTO_TLS1_1)
  68. #define MBEDTLS_SSL_MAX_MINOR_VERSION MBEDTLS_SSL_MINOR_VERSION_2
  69. #else
  70. #if defined(MBEDTLS_SSL_PROTO_TLS1)
  71. #define MBEDTLS_SSL_MAX_MINOR_VERSION MBEDTLS_SSL_MINOR_VERSION_1
  72. #else
  73. #if defined(MBEDTLS_SSL_PROTO_SSL3)
  74. #define MBEDTLS_SSL_MAX_MINOR_VERSION MBEDTLS_SSL_MINOR_VERSION_0
  75. #endif /* MBEDTLS_SSL_PROTO_SSL3 */
  76. #endif /* MBEDTLS_SSL_PROTO_TLS1 */
  77. #endif /* MBEDTLS_SSL_PROTO_TLS1_1 */
  78. #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
  79. #define MBEDTLS_SSL_INITIAL_HANDSHAKE 0
  80. #define MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS 1 /* In progress */
  81. #define MBEDTLS_SSL_RENEGOTIATION_DONE 2 /* Done or aborted */
  82. #define MBEDTLS_SSL_RENEGOTIATION_PENDING 3 /* Requested (server only) */
  83. /*
  84. * DTLS retransmission states, see RFC 6347 4.2.4
  85. *
  86. * The SENDING state is merged in PREPARING for initial sends,
  87. * but is distinct for resends.
  88. *
  89. * Note: initial state is wrong for server, but is not used anyway.
  90. */
  91. #define MBEDTLS_SSL_RETRANS_PREPARING 0
  92. #define MBEDTLS_SSL_RETRANS_SENDING 1
  93. #define MBEDTLS_SSL_RETRANS_WAITING 2
  94. #define MBEDTLS_SSL_RETRANS_FINISHED 3
  95. /*
  96. * Allow extra bytes for record, authentication and encryption overhead:
  97. * counter (8) + header (5) + IV(16) + MAC (16-48) + padding (0-256)
  98. * and allow for a maximum of 1024 of compression expansion if
  99. * enabled.
  100. */
  101. #if defined(MBEDTLS_ZLIB_SUPPORT)
  102. #define MBEDTLS_SSL_COMPRESSION_ADD 1024
  103. #else
  104. #define MBEDTLS_SSL_COMPRESSION_ADD 0
  105. #endif
  106. #if defined(MBEDTLS_ARC4_C) || defined(MBEDTLS_CIPHER_MODE_CBC)
  107. /* Ciphersuites using HMAC */
  108. #if defined(MBEDTLS_SHA512_C)
  109. #define MBEDTLS_SSL_MAC_ADD 48 /* SHA-384 used for HMAC */
  110. #elif defined(MBEDTLS_SHA256_C)
  111. #define MBEDTLS_SSL_MAC_ADD 32 /* SHA-256 used for HMAC */
  112. #else
  113. #define MBEDTLS_SSL_MAC_ADD 20 /* SHA-1 used for HMAC */
  114. #endif
  115. #else
  116. /* AEAD ciphersuites: GCM and CCM use a 128 bits tag */
  117. #define MBEDTLS_SSL_MAC_ADD 16
  118. #endif
  119. #if defined(MBEDTLS_CIPHER_MODE_CBC)
  120. #define MBEDTLS_SSL_PADDING_ADD 256
  121. #else
  122. #define MBEDTLS_SSL_PADDING_ADD 0
  123. #endif
  124. #define MBEDTLS_SSL_BUFFER_LEN ( MBEDTLS_SSL_MAX_CONTENT_LEN \
  125. + MBEDTLS_SSL_COMPRESSION_ADD \
  126. + 29 /* counter + header + IV */ \
  127. + MBEDTLS_SSL_MAC_ADD \
  128. + MBEDTLS_SSL_PADDING_ADD \
  129. )
  130. /*
  131. * TLS extension flags (for extensions with outgoing ServerHello content
  132. * that need it (e.g. for RENEGOTIATION_INFO the server already knows because
  133. * of state of the renegotiation flag, so no indicator is required)
  134. */
  135. #define MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS_PRESENT (1 << 0)
  136. #define MBEDTLS_TLS_EXT_ECJPAKE_KKPP_OK (1 << 1)
  137. #ifdef __cplusplus
  138. extern "C" {
  139. #endif
  140. /*
  141. * This structure contains the parameters only needed during handshake.
  142. */
  143. struct mbedtls_ssl_handshake_params
  144. {
  145. /*
  146. * Handshake specific crypto variables
  147. */
  148. int sig_alg; /*!< Hash algorithm for signature */
  149. int cert_type; /*!< Requested cert type */
  150. int verify_sig_alg; /*!< Signature algorithm for verify */
  151. #if defined(MBEDTLS_DHM_C)
  152. mbedtls_dhm_context dhm_ctx; /*!< DHM key exchange */
  153. #endif
  154. #if defined(MBEDTLS_ECDH_C)
  155. mbedtls_ecdh_context ecdh_ctx; /*!< ECDH key exchange */
  156. #endif
  157. #if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
  158. mbedtls_ecjpake_context ecjpake_ctx; /*!< EC J-PAKE key exchange */
  159. #if defined(MBEDTLS_SSL_CLI_C)
  160. unsigned char *ecjpake_cache; /*!< Cache for ClientHello ext */
  161. size_t ecjpake_cache_len; /*!< Length of cached data */
  162. #endif
  163. #endif
  164. #if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
  165. defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
  166. const mbedtls_ecp_curve_info **curves; /*!< Supported elliptic curves */
  167. #endif
  168. #if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
  169. unsigned char *psk; /*!< PSK from the callback */
  170. size_t psk_len; /*!< Length of PSK from callback */
  171. #endif
  172. #if defined(MBEDTLS_X509_CRT_PARSE_C)
  173. mbedtls_ssl_key_cert *key_cert; /*!< chosen key/cert pair (server) */
  174. #if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
  175. int sni_authmode; /*!< authmode from SNI callback */
  176. mbedtls_ssl_key_cert *sni_key_cert; /*!< key/cert list from SNI */
  177. mbedtls_x509_crt *sni_ca_chain; /*!< trusted CAs from SNI callback */
  178. mbedtls_x509_crl *sni_ca_crl; /*!< trusted CAs CRLs from SNI */
  179. #endif
  180. #endif /* MBEDTLS_X509_CRT_PARSE_C */
  181. #if defined(MBEDTLS_SSL_PROTO_DTLS)
  182. unsigned int out_msg_seq; /*!< Outgoing handshake sequence number */
  183. unsigned int in_msg_seq; /*!< Incoming handshake sequence number */
  184. unsigned char *verify_cookie; /*!< Cli: HelloVerifyRequest cookie
  185. Srv: unused */
  186. unsigned char verify_cookie_len; /*!< Cli: cookie length
  187. Srv: flag for sending a cookie */
  188. unsigned char *hs_msg; /*!< Reassembled handshake message */
  189. uint32_t retransmit_timeout; /*!< Current value of timeout */
  190. unsigned char retransmit_state; /*!< Retransmission state */
  191. mbedtls_ssl_flight_item *flight; /*!< Current outgoing flight */
  192. mbedtls_ssl_flight_item *cur_msg; /*!< Current message in flight */
  193. unsigned int in_flight_start_seq; /*!< Minimum message sequence in the
  194. flight being received */
  195. mbedtls_ssl_transform *alt_transform_out; /*!< Alternative transform for
  196. resending messages */
  197. unsigned char alt_out_ctr[8]; /*!< Alternative record epoch/counter
  198. for resending messages */
  199. #endif
  200. /*
  201. * Checksum contexts
  202. */
  203. #if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \
  204. defined(MBEDTLS_SSL_PROTO_TLS1_1)
  205. mbedtls_md5_context fin_md5;
  206. mbedtls_sha1_context fin_sha1;
  207. #endif
  208. #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
  209. #if defined(MBEDTLS_SHA256_C)
  210. mbedtls_sha256_context fin_sha256;
  211. #endif
  212. #if defined(MBEDTLS_SHA512_C)
  213. mbedtls_sha512_context fin_sha512;
  214. #endif
  215. #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
  216. void (*update_checksum)(mbedtls_ssl_context *, const unsigned char *, size_t);
  217. void (*calc_verify)(mbedtls_ssl_context *, unsigned char *);
  218. void (*calc_finished)(mbedtls_ssl_context *, unsigned char *, int);
  219. int (*tls_prf)(const unsigned char *, size_t, const char *,
  220. const unsigned char *, size_t,
  221. unsigned char *, size_t);
  222. size_t pmslen; /*!< premaster length */
  223. unsigned char randbytes[64]; /*!< random bytes */
  224. unsigned char premaster[MBEDTLS_PREMASTER_SIZE];
  225. /*!< premaster secret */
  226. int resume; /*!< session resume indicator*/
  227. int max_major_ver; /*!< max. major version client*/
  228. int max_minor_ver; /*!< max. minor version client*/
  229. int cli_exts; /*!< client extension presence*/
  230. #if defined(MBEDTLS_SSL_SESSION_TICKETS)
  231. int new_session_ticket; /*!< use NewSessionTicket? */
  232. #endif /* MBEDTLS_SSL_SESSION_TICKETS */
  233. #if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
  234. int extended_ms; /*!< use Extended Master Secret? */
  235. #endif
  236. };
  237. /*
  238. * This structure contains a full set of runtime transform parameters
  239. * either in negotiation or active.
  240. */
  241. struct mbedtls_ssl_transform
  242. {
  243. /*
  244. * Session specific crypto layer
  245. */
  246. const mbedtls_ssl_ciphersuite_t *ciphersuite_info;
  247. /*!< Chosen cipersuite_info */
  248. unsigned int keylen; /*!< symmetric key length (bytes) */
  249. size_t minlen; /*!< min. ciphertext length */
  250. size_t ivlen; /*!< IV length */
  251. size_t fixed_ivlen; /*!< Fixed part of IV (AEAD) */
  252. size_t maclen; /*!< MAC length */
  253. unsigned char iv_enc[16]; /*!< IV (encryption) */
  254. unsigned char iv_dec[16]; /*!< IV (decryption) */
  255. #if defined(MBEDTLS_SSL_PROTO_SSL3)
  256. /* Needed only for SSL v3.0 secret */
  257. unsigned char mac_enc[20]; /*!< SSL v3.0 secret (enc) */
  258. unsigned char mac_dec[20]; /*!< SSL v3.0 secret (dec) */
  259. #endif /* MBEDTLS_SSL_PROTO_SSL3 */
  260. mbedtls_md_context_t md_ctx_enc; /*!< MAC (encryption) */
  261. mbedtls_md_context_t md_ctx_dec; /*!< MAC (decryption) */
  262. mbedtls_cipher_context_t cipher_ctx_enc; /*!< encryption context */
  263. mbedtls_cipher_context_t cipher_ctx_dec; /*!< decryption context */
  264. /*
  265. * Session specific compression layer
  266. */
  267. #if defined(MBEDTLS_ZLIB_SUPPORT)
  268. z_stream ctx_deflate; /*!< compression context */
  269. z_stream ctx_inflate; /*!< decompression context */
  270. #endif
  271. };
  272. #if defined(MBEDTLS_X509_CRT_PARSE_C)
  273. /*
  274. * List of certificate + private key pairs
  275. */
  276. struct mbedtls_ssl_key_cert
  277. {
  278. mbedtls_x509_crt *cert; /*!< cert */
  279. mbedtls_pk_context *key; /*!< private key */
  280. mbedtls_ssl_key_cert *next; /*!< next key/cert pair */
  281. };
  282. #endif /* MBEDTLS_X509_CRT_PARSE_C */
  283. #if defined(MBEDTLS_SSL_PROTO_DTLS)
  284. /*
  285. * List of handshake messages kept around for resending
  286. */
  287. struct mbedtls_ssl_flight_item
  288. {
  289. unsigned char *p; /*!< message, including handshake headers */
  290. size_t len; /*!< length of p */
  291. unsigned char type; /*!< type of the message: handshake or CCS */
  292. mbedtls_ssl_flight_item *next; /*!< next handshake message(s) */
  293. };
  294. #endif /* MBEDTLS_SSL_PROTO_DTLS */
  295. /**
  296. * \brief Free referenced items in an SSL transform context and clear
  297. * memory
  298. *
  299. * \param transform SSL transform context
  300. */
  301. void mbedtls_ssl_transform_free( mbedtls_ssl_transform *transform );
  302. /**
  303. * \brief Free referenced items in an SSL handshake context and clear
  304. * memory
  305. *
  306. * \param handshake SSL handshake context
  307. */
  308. void mbedtls_ssl_handshake_free( mbedtls_ssl_handshake_params *handshake );
  309. int mbedtls_ssl_handshake_client_step( mbedtls_ssl_context *ssl );
  310. int mbedtls_ssl_handshake_server_step( mbedtls_ssl_context *ssl );
  311. void mbedtls_ssl_handshake_wrapup( mbedtls_ssl_context *ssl );
  312. int mbedtls_ssl_send_fatal_handshake_failure( mbedtls_ssl_context *ssl );
  313. void mbedtls_ssl_reset_checksum( mbedtls_ssl_context *ssl );
  314. int mbedtls_ssl_derive_keys( mbedtls_ssl_context *ssl );
  315. int mbedtls_ssl_read_record( mbedtls_ssl_context *ssl );
  316. int mbedtls_ssl_fetch_input( mbedtls_ssl_context *ssl, size_t nb_want );
  317. int mbedtls_ssl_write_record( mbedtls_ssl_context *ssl );
  318. int mbedtls_ssl_flush_output( mbedtls_ssl_context *ssl );
  319. int mbedtls_ssl_parse_certificate( mbedtls_ssl_context *ssl );
  320. int mbedtls_ssl_write_certificate( mbedtls_ssl_context *ssl );
  321. int mbedtls_ssl_parse_change_cipher_spec( mbedtls_ssl_context *ssl );
  322. int mbedtls_ssl_write_change_cipher_spec( mbedtls_ssl_context *ssl );
  323. int mbedtls_ssl_parse_finished( mbedtls_ssl_context *ssl );
  324. int mbedtls_ssl_write_finished( mbedtls_ssl_context *ssl );
  325. void mbedtls_ssl_optimize_checksum( mbedtls_ssl_context *ssl,
  326. const mbedtls_ssl_ciphersuite_t *ciphersuite_info );
  327. #if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
  328. int mbedtls_ssl_psk_derive_premaster( mbedtls_ssl_context *ssl, mbedtls_key_exchange_type_t key_ex );
  329. #endif
  330. #if defined(MBEDTLS_PK_C)
  331. unsigned char mbedtls_ssl_sig_from_pk( mbedtls_pk_context *pk );
  332. mbedtls_pk_type_t mbedtls_ssl_pk_alg_from_sig( unsigned char sig );
  333. #endif
  334. mbedtls_md_type_t mbedtls_ssl_md_alg_from_hash( unsigned char hash );
  335. unsigned char mbedtls_ssl_hash_from_md_alg( int md );
  336. #if defined(MBEDTLS_ECP_C)
  337. int mbedtls_ssl_check_curve( const mbedtls_ssl_context *ssl, mbedtls_ecp_group_id grp_id );
  338. #endif
  339. #if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED)
  340. int mbedtls_ssl_check_sig_hash( const mbedtls_ssl_context *ssl,
  341. mbedtls_md_type_t md );
  342. #endif
  343. #if defined(MBEDTLS_X509_CRT_PARSE_C)
  344. static inline mbedtls_pk_context *mbedtls_ssl_own_key( mbedtls_ssl_context *ssl )
  345. {
  346. mbedtls_ssl_key_cert *key_cert;
  347. if( ssl->handshake != NULL && ssl->handshake->key_cert != NULL )
  348. key_cert = ssl->handshake->key_cert;
  349. else
  350. key_cert = ssl->conf->key_cert;
  351. return( key_cert == NULL ? NULL : key_cert->key );
  352. }
  353. static inline mbedtls_x509_crt *mbedtls_ssl_own_cert( mbedtls_ssl_context *ssl )
  354. {
  355. mbedtls_ssl_key_cert *key_cert;
  356. if( ssl->handshake != NULL && ssl->handshake->key_cert != NULL )
  357. key_cert = ssl->handshake->key_cert;
  358. else
  359. key_cert = ssl->conf->key_cert;
  360. return( key_cert == NULL ? NULL : key_cert->cert );
  361. }
  362. /*
  363. * Check usage of a certificate wrt extensions:
  364. * keyUsage, extendedKeyUsage (later), and nSCertType (later).
  365. *
  366. * Warning: cert_endpoint is the endpoint of the cert (ie, of our peer when we
  367. * check a cert we received from them)!
  368. *
  369. * Return 0 if everything is OK, -1 if not.
  370. */
  371. int mbedtls_ssl_check_cert_usage( const mbedtls_x509_crt *cert,
  372. const mbedtls_ssl_ciphersuite_t *ciphersuite,
  373. int cert_endpoint,
  374. uint32_t *flags );
  375. #endif /* MBEDTLS_X509_CRT_PARSE_C */
  376. void mbedtls_ssl_write_version( int major, int minor, int transport,
  377. unsigned char ver[2] );
  378. void mbedtls_ssl_read_version( int *major, int *minor, int transport,
  379. const unsigned char ver[2] );
  380. static inline size_t mbedtls_ssl_hdr_len( const mbedtls_ssl_context *ssl )
  381. {
  382. #if defined(MBEDTLS_SSL_PROTO_DTLS)
  383. if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
  384. return( 13 );
  385. #else
  386. ((void) ssl);
  387. #endif
  388. return( 5 );
  389. }
  390. static inline size_t mbedtls_ssl_hs_hdr_len( const mbedtls_ssl_context *ssl )
  391. {
  392. #if defined(MBEDTLS_SSL_PROTO_DTLS)
  393. if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
  394. return( 12 );
  395. #else
  396. ((void) ssl);
  397. #endif
  398. return( 4 );
  399. }
  400. #if defined(MBEDTLS_SSL_PROTO_DTLS)
  401. void mbedtls_ssl_send_flight_completed( mbedtls_ssl_context *ssl );
  402. void mbedtls_ssl_recv_flight_completed( mbedtls_ssl_context *ssl );
  403. int mbedtls_ssl_resend( mbedtls_ssl_context *ssl );
  404. #endif
  405. /* Visible for testing purposes only */
  406. #if defined(MBEDTLS_SSL_DTLS_ANTI_REPLAY)
  407. int mbedtls_ssl_dtls_replay_check( mbedtls_ssl_context *ssl );
  408. void mbedtls_ssl_dtls_replay_update( mbedtls_ssl_context *ssl );
  409. #endif
  410. /* constant-time buffer comparison */
  411. static inline int mbedtls_ssl_safer_memcmp( const void *a, const void *b, size_t n )
  412. {
  413. size_t i;
  414. const unsigned char *A = (const unsigned char *) a;
  415. const unsigned char *B = (const unsigned char *) b;
  416. unsigned char diff = 0;
  417. for( i = 0; i < n; i++ )
  418. diff |= A[i] ^ B[i];
  419. return( diff );
  420. }
  421. #ifdef __cplusplus
  422. }
  423. #endif
  424. #endif /* ssl_internal.h */