/**
* \file ssl.h
*
* Copyright (C) 2006-2009, Paul Bakker <polarssl_maintainer at polarssl.org>
* All rights reserved.
*
* Joined copyright on original XySSL code with: Christophe Devine
*
* 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 <time.h>
#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 */