/** * \file ssl.h * * Copyright (C) 2006-2009, Paul Bakker * All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ #ifndef POLARSSL_SSL_H #define POLARSSL_SSL_H #include #include "polarssl/net.h" #include "polarssl/dhm.h" #include "polarssl/rsa.h" #include "polarssl/md5.h" #include "polarssl/sha1.h" #include "polarssl/x509.h" /* * SSL Error codes */ #define POLARSSL_ERR_SSL_FEATURE_UNAVAILABLE -0x1000 #define POLARSSL_ERR_SSL_BAD_INPUT_DATA -0x1800 #define POLARSSL_ERR_SSL_INVALID_MAC -0x2000 #define POLARSSL_ERR_SSL_INVALID_RECORD -0x2800 #define POLARSSL_ERR_SSL_INVALID_MODULUS_SIZE -0x3000 #define POLARSSL_ERR_SSL_UNKNOWN_CIPHER -0x3800 #define POLARSSL_ERR_SSL_NO_CIPHER_CHOSEN -0x4000 #define POLARSSL_ERR_SSL_NO_SESSION_FOUND -0x4800 #define POLARSSL_ERR_SSL_NO_CLIENT_CERTIFICATE -0x5000 #define POLARSSL_ERR_SSL_CERTIFICATE_TOO_LARGE -0x5800 #define POLARSSL_ERR_SSL_CERTIFICATE_REQUIRED -0x6000 #define POLARSSL_ERR_SSL_PRIVATE_KEY_REQUIRED -0x6800 #define POLARSSL_ERR_SSL_CA_CHAIN_REQUIRED -0x7000 #define POLARSSL_ERR_SSL_UNEXPECTED_MESSAGE -0x7800 #define POLARSSL_ERR_SSL_FATAL_ALERT_MESSAGE -0x8000 #define POLARSSL_ERR_SSL_PEER_VERIFY_FAILED -0x8800 #define POLARSSL_ERR_SSL_PEER_CLOSE_NOTIFY -0x9000 #define POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO -0x9800 #define POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO -0xA000 #define POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE -0xA800 #define POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST -0xB000 #define POLARSSL_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE -0xB800 #define POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO_DONE -0xC000 #define POLARSSL_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE -0xC800 #define POLARSSL_ERR_SSL_BAD_HS_CERTIFICATE_VERIFY -0xD000 #define POLARSSL_ERR_SSL_BAD_HS_CHANGE_CIPHER_SPEC -0xD800 #define POLARSSL_ERR_SSL_BAD_HS_FINISHED -0xE000 /* * Various constants */ #define SSL_MAJOR_VERSION_3 3 #define SSL_MINOR_VERSION_0 0 /*!< SSL v3.0 */ #define SSL_MINOR_VERSION_1 1 /*!< TLS v1.0 */ #define SSL_MINOR_VERSION_2 2 /*!< TLS v1.1 */ #define SSL_IS_CLIENT 0 #define SSL_IS_SERVER 1 #define SSL_COMPRESS_NULL 0 #define SSL_VERIFY_NONE 0 #define SSL_VERIFY_OPTIONAL 1 #define SSL_VERIFY_REQUIRED 2 #define SSL_MAX_CONTENT_LEN 16384 /* * Allow an extra 512 bytes for the record header * and encryption overhead (counter + MAC + padding). */ #define SSL_BUFFER_LEN (SSL_MAX_CONTENT_LEN + 512) /* * Supported ciphersuites */ #define SSL_RSA_RC4_128_MD5 4 #define SSL_RSA_RC4_128_SHA 5 #define SSL_RSA_DES_168_SHA 10 #define SSL_EDH_RSA_DES_168_SHA 22 #define SSL_RSA_AES_128_SHA 47 #define SSL_RSA_AES_256_SHA 53 #define SSL_EDH_RSA_AES_256_SHA 57 #define SSL_RSA_CAMELLIA_128_SHA 0x41 #define SSL_RSA_CAMELLIA_256_SHA 0x84 #define SSL_EDH_RSA_CAMELLIA_256_SHA 0x88 /* * Message, alert and handshake types */ #define SSL_MSG_CHANGE_CIPHER_SPEC 20 #define SSL_MSG_ALERT 21 #define SSL_MSG_HANDSHAKE 22 #define SSL_MSG_APPLICATION_DATA 23 #define SSL_ALERT_CLOSE_NOTIFY 0 #define SSL_ALERT_WARNING 1 #define SSL_ALERT_FATAL 2 #define SSL_ALERT_NO_CERTIFICATE 41 #define SSL_HS_HELLO_REQUEST 0 #define SSL_HS_CLIENT_HELLO 1 #define SSL_HS_SERVER_HELLO 2 #define SSL_HS_CERTIFICATE 11 #define SSL_HS_SERVER_KEY_EXCHANGE 12 #define SSL_HS_CERTIFICATE_REQUEST 13 #define SSL_HS_SERVER_HELLO_DONE 14 #define SSL_HS_CERTIFICATE_VERIFY 15 #define SSL_HS_CLIENT_KEY_EXCHANGE 16 #define SSL_HS_FINISHED 20 /* * TLS extensions */ #define TLS_EXT_SERVERNAME 0 #define TLS_EXT_SERVERNAME_HOSTNAME 0 /* * SSL state machine */ typedef enum { SSL_HELLO_REQUEST, SSL_CLIENT_HELLO, SSL_SERVER_HELLO, SSL_SERVER_CERTIFICATE, SSL_SERVER_KEY_EXCHANGE, SSL_CERTIFICATE_REQUEST, SSL_SERVER_HELLO_DONE, SSL_CLIENT_CERTIFICATE, SSL_CLIENT_KEY_EXCHANGE, SSL_CERTIFICATE_VERIFY, SSL_CLIENT_CHANGE_CIPHER_SPEC, SSL_CLIENT_FINISHED, SSL_SERVER_CHANGE_CIPHER_SPEC, SSL_SERVER_FINISHED, SSL_FLUSH_BUFFERS, SSL_HANDSHAKE_OVER } ssl_states; typedef struct _ssl_session ssl_session; typedef struct _ssl_context ssl_context; /* * This structure is used for session resuming. */ struct _ssl_session { time_t start; /*!< starting time */ int cipher; /*!< chosen cipher */ int length; /*!< session id length */ unsigned char id[32]; /*!< session identifier */ unsigned char master[48]; /*!< the master secret */ ssl_session *next; /*!< next session entry */ }; struct _ssl_context { /* * Miscellaneous */ int state; /*!< SSL handshake: current state */ int major_ver; /*!< equal to SSL_MAJOR_VERSION_3 */ int minor_ver; /*!< either 0 (SSL3) or 1 (TLS1.0) */ int max_major_ver; /*!< max. major version from client */ int max_minor_ver; /*!< max. minor version from client */ /* * Callbacks (RNG, debug, I/O) */ int (*f_rng)(void *); void (*f_dbg)(void *, int, const char *); int (*f_recv)(void *, unsigned char *, int); int (*f_send)(void *, unsigned char *, int); void *p_rng; /*!< context for the RNG function */ void *p_dbg; /*!< context for the debug function */ void *p_recv; /*!< context for reading operations */ void *p_send; /*!< context for writing operations */ /* * Session layer */ int resume; /*!< session resuming flag */ int timeout; /*!< sess. expiration time */ ssl_session *session; /*!< current session data */ int (*s_get)(ssl_context *); /*!< (server) get callback */ int (*s_set)(ssl_context *); /*!< (server) set callback */ /* * Record layer (incoming data) */ unsigned char *in_ctr; /*!< 64-bit incoming message counter */ unsigned char *in_hdr; /*!< 5-byte record header (in_ctr+8) */ unsigned char *in_msg; /*!< the message contents (in_hdr+5) */ unsigned char *in_offt; /*!< read offset in application data */ int in_msgtype; /*!< record header: message type */ int in_msglen; /*!< record header: message length */ int in_left; /*!< amount of data read so far */ int in_hslen; /*!< current handshake message length */ int nb_zero; /*!< # of 0-length encrypted messages */ /* * Record layer (outgoing data) */ unsigned char *out_ctr; /*!< 64-bit outgoing message counter */ unsigned char *out_hdr; /*!< 5-byte record header (out_ctr+8) */ unsigned char *out_msg; /*!< the message contents (out_hdr+5) */ int out_msgtype; /*!< record header: message type */ int out_msglen; /*!< record header: message length */ int out_left; /*!< amount of data not yet written */ /* * PKI layer */ rsa_context *rsa_key; /*!< own RSA private key */ x509_cert *own_cert; /*!< own X.509 certificate */ x509_cert *ca_chain; /*!< own trusted CA chain */ x509_crl *ca_crl; /*!< trusted CA CRLs */ x509_cert *peer_cert; /*!< peer X.509 cert chain */ char *peer_cn; /*!< expected peer CN */ int endpoint; /*!< 0: client, 1: server */ int authmode; /*!< verification mode */ int client_auth; /*!< flag for client auth. */ int verify_result; /*!< verification result */ /* * Crypto layer */ dhm_context dhm_ctx; /*!< DHM key exchange */ md5_context fin_md5; /*!< Finished MD5 checksum */ sha1_context fin_sha1; /*!< Finished SHA-1 checksum */ int do_crypt; /*!< en(de)cryption flag */ int *ciphers; /*!< allowed ciphersuites */ int pmslen; /*!< premaster length */ int keylen; /*!< symmetric key length */ int minlen; /*!< min. ciphertext length */ int ivlen; /*!< IV length */ int maclen; /*!< MAC length */ unsigned char randbytes[64]; /*!< random bytes */ unsigned char premaster[256]; /*!< premaster secret */ unsigned char iv_enc[16]; /*!< IV (encryption) */ unsigned char iv_dec[16]; /*!< IV (decryption) */ unsigned char mac_enc[32]; /*!< MAC (encryption) */ unsigned char mac_dec[32]; /*!< MAC (decryption) */ unsigned long ctx_enc[128]; /*!< encryption context */ unsigned long ctx_dec[128]; /*!< decryption context */ /* * TLS extensions */ unsigned char *hostname; unsigned long hostname_len; }; #ifdef __cplusplus extern "C" { #endif extern int ssl_default_ciphers[]; /** * \brief Initialize an SSL context * * \param ssl SSL context * * \return 0 if successful, or 1 if memory allocation failed */ int ssl_init( ssl_context *ssl ); /** * \brief Set the current endpoint type * * \param ssl SSL context * \param endpoint must be SSL_IS_CLIENT or SSL_IS_SERVER */ void ssl_set_endpoint( ssl_context *ssl, int endpoint ); /** * \brief Set the certificate verification mode * * \param ssl SSL context * \param mode can be: * * SSL_VERIFY_NONE: peer certificate is not checked (default), * this is insecure and SHOULD be avoided. * * SSL_VERIFY_OPTIONAL: peer certificate is checked, however the * handshake continues even if verification failed; * ssl_get_verify_result() can be called after the * handshake is complete. * * SSL_VERIFY_REQUIRED: peer *must* present a valid certificate, * handshake is aborted if verification failed. */ void ssl_set_authmode( ssl_context *ssl, int authmode ); /** * \brief Set the random number generator callback * * \param ssl SSL context * \param f_rng RNG function * \param p_rng RNG parameter */ void ssl_set_rng( ssl_context *ssl, int (*f_rng)(void *), void *p_rng ); /** * \brief Set the debug callback * * \param ssl SSL context * \param f_dbg debug function * \param p_dbg debug parameter */ void ssl_set_dbg( ssl_context *ssl, void (*f_dbg)(void *, int, const char *), void *p_dbg ); /** * \brief Set the underlying BIO read and write callbacks * * \param ssl SSL context * \param f_recv read callback * \param p_recv read parameter * \param f_send write callback * \param p_send write parameter */ void ssl_set_bio( ssl_context *ssl, int (*f_recv)(void *, unsigned char *, int), void *p_recv, int (*f_send)(void *, unsigned char *, int), void *p_send ); /** * \brief Set the session callbacks (server-side only) * * \param ssl SSL context * \param s_get session get callback * \param s_set session set callback */ void ssl_set_scb( ssl_context *ssl, int (*s_get)(ssl_context *), int (*s_set)(ssl_context *) ); /** * \brief Set the session resuming flag, timeout and data * * \param ssl SSL context * \param resume if 0 (default), the session will not be resumed * \param timeout session timeout in seconds, or 0 (no timeout) * \param session session context */ void ssl_set_session( ssl_context *ssl, int resume, int timeout, ssl_session *session ); /** * \brief Set the list of allowed ciphersuites * * \param ssl SSL context * \param ciphers 0-terminated list of allowed ciphers */ void ssl_set_ciphers( ssl_context *ssl, int *ciphers ); /** * \brief Set the data required to verify peer certificate * * \param ssl SSL context * \param ca_chain trusted CA chain * \param ca_crl trusted CA CRLs * \param peer_cn expected peer CommonName (or NULL) * * \note TODO: add two more parameters: depth and crl */ void ssl_set_ca_chain( ssl_context *ssl, x509_cert *ca_chain, x509_crl *ca_crl, char *peer_cn ); /** * \brief Set own certificate and private key * * \param ssl SSL context * \param own_cert own public certificate * \param rsa_key own private RSA key */ void ssl_set_own_cert( ssl_context *ssl, x509_cert *own_cert, rsa_context *rsa_key ); /** * \brief Set the Diffie-Hellman public P and G values, * read as hexadecimal strings (server-side only) * * \param ssl SSL context * \param dhm_P Diffie-Hellman-Merkle modulus * \param dhm_G Diffie-Hellman-Merkle generator * * \return 0 if successful */ int ssl_set_dh_param( ssl_context *ssl, const char *dhm_P, const char *dhm_G ); /** * \brief Set hostname for ServerName TLS Extension * * * \param ssl SSL context * \param hostname the server hostname * * \return 0 if successful */ int ssl_set_hostname( ssl_context *ssl, const char *hostname ); /** * \brief Return the number of data bytes available to read * * \param ssl SSL context * * \return how many bytes are available in the read buffer */ int ssl_get_bytes_avail( const ssl_context *ssl ); /** * \brief Return the result of the certificate verification * * \param ssl SSL context * * \return 0 if successful, or a combination of: * BADCERT_EXPIRED * BADCERT_REVOKED * BADCERT_CN_MISMATCH * BADCERT_NOT_TRUSTED */ int ssl_get_verify_result( const ssl_context *ssl ); /** * \brief Return the name of the current cipher * * \param ssl SSL context * * \return a string containing the cipher name */ const char *ssl_get_cipher( const ssl_context *ssl ); /** * \brief Perform the SSL handshake * * \param ssl SSL context * * \return 0 if successful, POLARSSL_ERR_NET_TRY_AGAIN, * or a specific SSL error code. */ int ssl_handshake( ssl_context *ssl ); /** * \brief Read at most 'len' application data bytes * * \param ssl SSL context * \param buf buffer that will hold the data * \param len how many bytes must be read * * \return This function returns the number of bytes read, * or a negative error code. */ int ssl_read( ssl_context *ssl, unsigned char *buf, int len ); /** * \brief Write exactly 'len' application data bytes * * \param ssl SSL context * \param buf buffer holding the data * \param len how many bytes must be written * * \return This function returns the number of bytes written, * or a negative error code. * * \note When this function returns POLARSSL_ERR_NET_TRY_AGAIN, * it must be called later with the *same* arguments, * until it returns a positive value. */ int ssl_write( ssl_context *ssl, const unsigned char *buf, int len ); /** * \brief Notify the peer that the connection is being closed * * \param ssl SSL context */ int ssl_close_notify( ssl_context *ssl ); /** * \brief Free an SSL context * * \param ssl SSL context */ void ssl_free( ssl_context *ssl ); /* * Internal functions (do not call directly) */ int ssl_handshake_client( ssl_context *ssl ); int ssl_handshake_server( ssl_context *ssl ); int ssl_derive_keys( ssl_context *ssl ); void ssl_calc_verify( ssl_context *ssl, unsigned char hash[36] ); int ssl_read_record( ssl_context *ssl ); int ssl_fetch_input( ssl_context *ssl, int nb_want ); int ssl_write_record( ssl_context *ssl ); int ssl_flush_output( ssl_context *ssl ); int ssl_parse_certificate( ssl_context *ssl ); int ssl_write_certificate( ssl_context *ssl ); int ssl_parse_change_cipher_spec( ssl_context *ssl ); int ssl_write_change_cipher_spec( ssl_context *ssl ); int ssl_parse_finished( ssl_context *ssl ); int ssl_write_finished( ssl_context *ssl ); #ifdef __cplusplus } #endif #endif /* ssl.h */