ssl.h

/* ssl/ssl.h */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@cryptsoft.com).
 * The implementation was written so as to conform with Netscapes SSL.
 * 
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
 * 
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young (eay@cryptsoft.com)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from 
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
 * 
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * 
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */
/* ====================================================================
 * Copyright (c) 1998-2007 The OpenSSL Project.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    openssl-core@openssl.org.
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * (eay@cryptsoft.com).  This product includes software written by Tim
 * Hudson (tjh@cryptsoft.com).
 *
 */
/* ====================================================================
 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
 * ECC cipher suite support in OpenSSL originally developed by 
 * SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
 */
/* ====================================================================
 * Copyright 2005 Nokia. All rights reserved.
 *
 * The portions of the attached software ("Contribution") is developed by
 * Nokia Corporation and is licensed pursuant to the OpenSSL open source
 * license.
 *
 * The Contribution, originally written by Mika Kousa and Pasi Eronen of
 * Nokia Corporation, consists of the "PSK" (Pre-Shared Key) ciphersuites
 * support (see RFC 4279) to OpenSSL.
 *
 * No patent licenses or other rights except those expressly stated in
 * the OpenSSL open source license shall be deemed granted or received
 * expressly, by implication, estoppel, or otherwise.
 *
 * No assurances are provided by Nokia that the Contribution does not
 * infringe the patent or other intellectual property rights of any third
 * party or that the license provides you with all the necessary rights
 * to make use of the Contribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. IN
 * ADDITION TO THE DISCLAIMERS INCLUDED IN THE LICENSE, NOKIA
 * SPECIFICALLY DISCLAIMS ANY LIABILITY FOR CLAIMS BROUGHT BY YOU OR ANY
 * OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OR
 * OTHERWISE.
 */

#ifndef HEADER_SSL_H 
#define HEADER_SSL_H 

#include <openssl/e_os2.h>

#ifndef OPENSSL_NO_COMP
#include <openssl/comp.h>
#endif
#ifndef OPENSSL_NO_BIO
#include <openssl/bio.h>
#endif
#ifndef OPENSSL_NO_DEPRECATED
#ifndef OPENSSL_NO_X509
#include <openssl/x509.h>
#endif
#include <openssl/crypto.h>
#include <openssl/lhash.h>
#include <openssl/buffer.h>
#endif
#include <openssl/pem.h>
#include <openssl/hmac.h>

#include <openssl/kssl.h>
#include <openssl/safestack.h>
#include <openssl/symhacks.h>

#ifdef  __cplusplus
extern "C" {
#endif

/* SSLeay version number for ASN.1 encoding of the session information */
/* Version 0 - initial version
 * Version 1 - added the optional peer certificate
 */
#define SSL_SESSION_ASN1_VERSION 0x0001

/* text strings for the ciphers */
#define SSL_TXT_NULL_WITH_MD5		SSL2_TXT_NULL_WITH_MD5			
#define SSL_TXT_RC4_128_WITH_MD5	SSL2_TXT_RC4_128_WITH_MD5		
#define SSL_TXT_RC4_128_EXPORT40_WITH_MD5 SSL2_TXT_RC4_128_EXPORT40_WITH_MD5	
#define SSL_TXT_RC2_128_CBC_WITH_MD5	SSL2_TXT_RC2_128_CBC_WITH_MD5		
#define SSL_TXT_RC2_128_CBC_EXPORT40_WITH_MD5 SSL2_TXT_RC2_128_CBC_EXPORT40_WITH_MD5	
#define SSL_TXT_IDEA_128_CBC_WITH_MD5	SSL2_TXT_IDEA_128_CBC_WITH_MD5		
#define SSL_TXT_DES_64_CBC_WITH_MD5	SSL2_TXT_DES_64_CBC_WITH_MD5		
#define SSL_TXT_DES_64_CBC_WITH_SHA	SSL2_TXT_DES_64_CBC_WITH_SHA		
#define SSL_TXT_DES_192_EDE3_CBC_WITH_MD5 SSL2_TXT_DES_192_EDE3_CBC_WITH_MD5	
#define SSL_TXT_DES_192_EDE3_CBC_WITH_SHA SSL2_TXT_DES_192_EDE3_CBC_WITH_SHA	

/*    VRS Additional Kerberos5 entries
 */
#define SSL_TXT_KRB5_DES_64_CBC_SHA   SSL3_TXT_KRB5_DES_64_CBC_SHA
#define SSL_TXT_KRB5_DES_192_CBC3_SHA SSL3_TXT_KRB5_DES_192_CBC3_SHA
#define SSL_TXT_KRB5_RC4_128_SHA      SSL3_TXT_KRB5_RC4_128_SHA
#define SSL_TXT_KRB5_IDEA_128_CBC_SHA SSL3_TXT_KRB5_IDEA_128_CBC_SHA
#define SSL_TXT_KRB5_DES_64_CBC_MD5   SSL3_TXT_KRB5_DES_64_CBC_MD5       
#define SSL_TXT_KRB5_DES_192_CBC3_MD5 SSL3_TXT_KRB5_DES_192_CBC3_MD5       
#define SSL_TXT_KRB5_RC4_128_MD5      SSL3_TXT_KRB5_RC4_128_MD5
#define SSL_TXT_KRB5_IDEA_128_CBC_MD5 SSL3_TXT_KRB5_IDEA_128_CBC_MD5 

#define SSL_TXT_KRB5_DES_40_CBC_SHA   SSL3_TXT_KRB5_DES_40_CBC_SHA 
#define SSL_TXT_KRB5_RC2_40_CBC_SHA   SSL3_TXT_KRB5_RC2_40_CBC_SHA 
#define SSL_TXT_KRB5_RC4_40_SHA	      SSL3_TXT_KRB5_RC4_40_SHA
#define SSL_TXT_KRB5_DES_40_CBC_MD5   SSL3_TXT_KRB5_DES_40_CBC_MD5 
#define SSL_TXT_KRB5_RC2_40_CBC_MD5   SSL3_TXT_KRB5_RC2_40_CBC_MD5 
#define SSL_TXT_KRB5_RC4_40_MD5	      SSL3_TXT_KRB5_RC4_40_MD5

#define SSL_TXT_KRB5_DES_40_CBC_SHA   SSL3_TXT_KRB5_DES_40_CBC_SHA
#define SSL_TXT_KRB5_DES_40_CBC_MD5   SSL3_TXT_KRB5_DES_40_CBC_MD5
#define SSL_TXT_KRB5_DES_64_CBC_SHA   SSL3_TXT_KRB5_DES_64_CBC_SHA
#define SSL_TXT_KRB5_DES_64_CBC_MD5   SSL3_TXT_KRB5_DES_64_CBC_MD5
#define SSL_TXT_KRB5_DES_192_CBC3_SHA SSL3_TXT_KRB5_DES_192_CBC3_SHA
#define SSL_TXT_KRB5_DES_192_CBC3_MD5 SSL3_TXT_KRB5_DES_192_CBC3_MD5
#define SSL_MAX_KRB5_PRINCIPAL_LENGTH  256

#define SSL_MAX_SSL_SESSION_ID_LENGTH		32
#define SSL_MAX_SID_CTX_LENGTH			32

#define SSL_MIN_RSA_MODULUS_LENGTH_IN_BYTES	(512/8)
#define SSL_MAX_KEY_ARG_LENGTH			8
#define SSL_MAX_MASTER_KEY_LENGTH		48


/* These are used to specify which ciphers to use and not to use */

#define SSL_TXT_EXP40		"EXPORT40"
#define SSL_TXT_EXP56		"EXPORT56"
#define SSL_TXT_LOW		"LOW"
#define SSL_TXT_MEDIUM		"MEDIUM"
#define SSL_TXT_HIGH		"HIGH"
#define SSL_TXT_FIPS		"FIPS"

#define SSL_TXT_kFZA		"kFZA" /* unused! */
#define	SSL_TXT_aFZA		"aFZA" /* unused! */
#define SSL_TXT_eFZA		"eFZA" /* unused! */
#define SSL_TXT_FZA		"FZA"  /* unused! */

#define	SSL_TXT_aNULL		"aNULL"
#define	SSL_TXT_eNULL		"eNULL"
#define	SSL_TXT_NULL		"NULL"

#define SSL_TXT_kRSA		"kRSA"
#define SSL_TXT_kDHr		"kDHr" 
#define SSL_TXT_kDHd		"kDHd"
#define SSL_TXT_kDH 		"kDH"
#define SSL_TXT_kEDH		"kEDH"
#define SSL_TXT_kKRB5     	"kKRB5"
#define SSL_TXT_kECDHr		"kECDHr"
#define SSL_TXT_kECDHe		"kECDHe"
#define SSL_TXT_kECDH		"kECDH"
#define SSL_TXT_kEECDH		"kEECDH"
#define SSL_TXT_kPSK            "kPSK"
#define SSL_TXT_kGOST		"kGOST"
#define SSL_TXT_kSRP		"kSRP"

#define	SSL_TXT_aRSA		"aRSA"
#define	SSL_TXT_aDSS		"aDSS"
#define	SSL_TXT_aDH		"aDH"
#define	SSL_TXT_aECDH		"aECDH"
#define SSL_TXT_aKRB5     	"aKRB5"
#define SSL_TXT_aECDSA		"aECDSA"
#define SSL_TXT_aPSK            "aPSK"
#define SSL_TXT_aGOST94	"aGOST94"
#define SSL_TXT_aGOST01 "aGOST01"
#define SSL_TXT_aGOST  "aGOST"

#define	SSL_TXT_DSS		"DSS"
#define SSL_TXT_DH		"DH"
#define SSL_TXT_EDH		"EDH" /* same as "kEDH:-ADH" */
#define SSL_TXT_ADH		"ADH"
#define SSL_TXT_RSA		"RSA"
#define SSL_TXT_ECDH		"ECDH"
#define SSL_TXT_EECDH		"EECDH" /* same as "kEECDH:-AECDH" */
#define SSL_TXT_AECDH		"AECDH"
#define SSL_TXT_ECDSA		"ECDSA"
#define SSL_TXT_KRB5      	"KRB5"
#define SSL_TXT_PSK             "PSK"
#define SSL_TXT_SRP		"SRP"

#define SSL_TXT_DES		"DES"
#define SSL_TXT_3DES		"3DES"
#define SSL_TXT_RC4		"RC4"
#define SSL_TXT_RC2		"RC2"
#define SSL_TXT_IDEA		"IDEA"
#define SSL_TXT_SEED		"SEED"
#define SSL_TXT_AES128		"AES128"
#define SSL_TXT_AES256		"AES256"
#define SSL_TXT_AES		"AES"
#define SSL_TXT_AES_GCM		"AESGCM"
#define SSL_TXT_CAMELLIA128	"CAMELLIA128"
#define SSL_TXT_CAMELLIA256	"CAMELLIA256"
#define SSL_TXT_CAMELLIA	"CAMELLIA"

#define SSL_TXT_MD5		"MD5"
#define SSL_TXT_SHA1		"SHA1"
#define SSL_TXT_SHA		"SHA" /* same as "SHA1" */
#define SSL_TXT_GOST94		"GOST94" 
#define SSL_TXT_GOST89MAC		"GOST89MAC" 
#define SSL_TXT_SHA256		"SHA256"
#define SSL_TXT_SHA384		"SHA384"

#define SSL_TXT_SSLV2		"SSLv2"
#define SSL_TXT_SSLV3		"SSLv3"
#define SSL_TXT_TLSV1		"TLSv1"
#define SSL_TXT_TLSV1_1		"TLSv1.1"
#define SSL_TXT_TLSV1_2		"TLSv1.2"

#define SSL_TXT_EXP		"EXP"
#define SSL_TXT_EXPORT		"EXPORT"

#define SSL_TXT_ALL		"ALL"

/*
 * COMPLEMENTOF* definitions. These identifiers are used to (de-select)
 * ciphers normally not being used.
 * Example: "RC4" will activate all ciphers using RC4 including ciphers
 * without authentication, which would normally disabled by DEFAULT (due
 * the "!ADH" being part of default). Therefore "RC4:!COMPLEMENTOFDEFAULT"
 * will make sure that it is also disabled in the specific selection.
 * COMPLEMENTOF* identifiers are portable between version, as adjustments
 * to the default cipher setup will also be included here.
 *
 * COMPLEMENTOFDEFAULT does not experience the same special treatment that
 * DEFAULT gets, as only selection is being done and no sorting as needed
 * for DEFAULT.
 */
#define SSL_TXT_CMPALL		"COMPLEMENTOFALL"
#define SSL_TXT_CMPDEF		"COMPLEMENTOFDEFAULT"

/* The following cipher list is used by default.
 * It also is substituted when an application-defined cipher list string
 * starts with 'DEFAULT'. */
#define SSL_DEFAULT_CIPHER_LIST	"ALL:!aNULL:!eNULL:!SSLv2"
/* As of OpenSSL 1.0.0, ssl_create_cipher_list() in ssl/ssl_ciph.c always
 * starts with a reasonable order, and all we have to do for DEFAULT is
 * throwing out anonymous and unencrypted ciphersuites!
 * (The latter are not actually enabled by ALL, but "ALL:RSA" would enable
 * some of them.)
 */

/* Used in SSL_set_shutdown()/SSL_get_shutdown(); */
#define SSL_SENT_SHUTDOWN	1
#define SSL_RECEIVED_SHUTDOWN	2

#ifdef __cplusplus
}
#endif

#ifdef  __cplusplus
extern "C" {
#endif

#if (defined(OPENSSL_NO_RSA) || defined(OPENSSL_NO_MD5)) && !defined(OPENSSL_NO_SSL2)
#define OPENSSL_NO_SSL2
#endif

#define SSL_FILETYPE_ASN1	X509_FILETYPE_ASN1
#define SSL_FILETYPE_PEM	X509_FILETYPE_PEM

/* This is needed to stop compilers complaining about the
 * 'struct ssl_st *' function parameters used to prototype callbacks
 * in SSL_CTX. */
typedef struct ssl_st *ssl_crock_st;
typedef struct tls_session_ticket_ext_st TLS_SESSION_TICKET_EXT;
typedef struct ssl_method_st SSL_METHOD;
typedef struct ssl_cipher_st SSL_CIPHER;
typedef struct ssl_session_st SSL_SESSION;
typedef struct tls_sigalgs_st TLS_SIGALGS;
typedef struct ssl_conf_ctx_st SSL_CONF_CTX;

DECLARE_STACK_OF(SSL_CIPHER)

/* SRTP protection profiles for use with the use_srtp extension (RFC 5764)*/
typedef struct srtp_protection_profile_st
       {
       const char *name;
       unsigned long id;
       } SRTP_PROTECTION_PROFILE;

DECLARE_STACK_OF(SRTP_PROTECTION_PROFILE)

typedef int (*tls_session_ticket_ext_cb_fn)(SSL *s, const unsigned char *data, int len, void *arg);
typedef int (*tls_session_secret_cb_fn)(SSL *s, void *secret, int *secret_len, STACK_OF(SSL_CIPHER) *peer_ciphers, SSL_CIPHER **cipher, void *arg);

#ifndef OPENSSL_NO_TLSEXT
/* Callbacks and structures for handling custom TLS Extensions: 
 *   cli_ext_first_cb  - sends data for ClientHello TLS Extension
 *   cli_ext_second_cb - receives data from ServerHello TLS Extension
 *   srv_ext_first_cb  - receives data from ClientHello TLS Extension
 *   srv_ext_second_cb - sends data for ServerHello TLS Extension
 *
 *   All these functions return nonzero on success.  Zero will terminate
 *   the handshake (and return a specific TLS Fatal alert, if the function
 *   declaration has an "al" parameter).  -1 for the "sending" functions
 *   will cause the TLS Extension to be omitted.
 * 
 *   "ext_type" is a TLS "ExtensionType" from 0-65535.
 *   "in" is a pointer to TLS "extension_data" being provided to the cb.
 *   "out" is used by the callback to return a pointer to "extension data"
 *     which OpenSSL will later copy into the TLS handshake.  The contents
 *     of this buffer should not be changed until the handshake is complete.
 *   "inlen" and "outlen" are TLS Extension lengths from 0-65535.
 *   "al" is a TLS "AlertDescription" from 0-255 which WILL be sent as a 
 *     fatal TLS alert, if the callback returns zero.
 */
typedef int (*custom_cli_ext_first_cb_fn)(SSL *s, unsigned short ext_type,
					  const unsigned char **out,
					  unsigned short *outlen, void *arg);
typedef int (*custom_cli_ext_second_cb_fn)(SSL *s, unsigned short ext_type,
					   const unsigned char *in,
					   unsigned short inlen, int *al,
					   void *arg); 

typedef int (*custom_srv_ext_first_cb_fn)(SSL *s, unsigned short ext_type,
					  const unsigned char *in,
					  unsigned short inlen, int *al,
					  void *arg);
typedef int (*custom_srv_ext_second_cb_fn)(SSL *s, unsigned short ext_type,
					   const unsigned char **out,
					   unsigned short *outlen, void *arg); 

typedef struct {
	unsigned short ext_type;
	custom_cli_ext_first_cb_fn fn1; 
	custom_cli_ext_second_cb_fn fn2; 
	void *arg;
} custom_cli_ext_record;

typedef struct {
	unsigned short ext_type;
	custom_srv_ext_first_cb_fn fn1; 
	custom_srv_ext_second_cb_fn fn2; 
	void *arg;
} custom_srv_ext_record;

/* Callbacks and structures for handling Supplemental Data:
 *   srv_supp_data_first_cb_fn  - server sends Supplemental Data
 *   srv_supp_data_second_cb_fn - server receives Supplemental Data
 *   cli_supp_data_first_cb_fn  - client receives Supplemental Data
 *   cli_supp_data_second_cb_fn - client sends Supplemental Data
 *
 *   All these functions return nonzero on success.  Zero will terminate
 *   the handshake (and return a specific TLS Fatal alert, if the function
 *   declaration has an "al" parameter).  -1 for the "sending" functions
 *   will result in no supplemental data entry being added to the
 *   supplemental data message for the provided supplemental data type.
 *
 *   "supp_data_type" is a Supplemental Data Type from 0-65535.
 *   "in" is a pointer to TLS "supplemental_data_entry" being provided to the cb.
 *   "out" is used by the callback to return a pointer to "supplemental data"
 *     which OpenSSL will later copy into the TLS handshake.  The contents
 *     of this buffer should not be changed until the handshake is complete.
 *   "inlen" and "outlen" are Supplemental Data lengths from 0-65535.
 *   "al" is a TLS "AlertDescription" from 0-255 which WILL be sent as a
 *     fatal TLS alert, if the callback returns zero.
 */
typedef int (*srv_supp_data_first_cb_fn)(SSL *s, unsigned short supp_data_type,
	     const unsigned char **out,
	     unsigned short *outlen, void *arg);
typedef int (*srv_supp_data_second_cb_fn)(SSL *s, unsigned short supp_data_type,
	     const unsigned char *in,
	     unsigned short inlen, int *al,
	     void *arg);

typedef int (*cli_supp_data_first_cb_fn)(SSL *s, unsigned short supp_data_type,
	     const unsigned char *in,
	     unsigned short inlen, int *al,
	     void *arg);
typedef int (*cli_supp_data_second_cb_fn)(SSL *s, unsigned short supp_data_type,
	     const unsigned char **out,
	     unsigned short *outlen, void *arg);

typedef struct {
	unsigned short supp_data_type;
	srv_supp_data_first_cb_fn fn1;
	srv_supp_data_second_cb_fn fn2;
	void *arg;
} srv_supp_data_record;

typedef struct {
	unsigned short supp_data_type;
	cli_supp_data_first_cb_fn fn1;
	cli_supp_data_second_cb_fn fn2;
	void *arg;
} cli_supp_data_record;

#endif

#ifndef OPENSSL_NO_SSL_INTERN

/* used to hold info on the particular ciphers used */
struct ssl_cipher_st
	{
	int valid;
	const char *name;		/* text name */
	unsigned long id;		/* id, 4 bytes, first is version */

	/* changed in 0.9.9: these four used to be portions of a single value 'algorithms' */
	unsigned long algorithm_mkey;	/* key exchange algorithm */
	unsigned long algorithm_auth;	/* server authentication */
	unsigned long algorithm_enc;	/* symmetric encryption */
	unsigned long algorithm_mac;	/* symmetric authentication */
	unsigned long algorithm_ssl;	/* (major) protocol version */

	unsigned long algo_strength;	/* strength and export flags */
	unsigned long algorithm2;	/* Extra flags */
	int strength_bits;		/* Number of bits really used */
	int alg_bits;			/* Number of bits for algorithm */
	};


/* Used to hold functions for SSLv2 or SSLv3/TLSv1 functions */
struct ssl_method_st
	{
	int version;
	int (*ssl_new)(SSL *s);
	void (*ssl_clear)(SSL *s);
	void (*ssl_free)(SSL *s);
	int (*ssl_accept)(SSL *s);
	int (*ssl_connect)(SSL *s);
	int (*ssl_read)(SSL *s,void *buf,int len);
	int (*ssl_peek)(SSL *s,void *buf,int len);
	int (*ssl_write)(SSL *s,const void *buf,int len);
	int (*ssl_shutdown)(SSL *s);
	int (*ssl_renegotiate)(SSL *s);
	int (*ssl_renegotiate_check)(SSL *s);
	long (*ssl_get_message)(SSL *s, int st1, int stn, int mt, long
		max, int *ok);
	int (*ssl_read_bytes)(SSL *s, int type, unsigned char *buf, int len, 
		int peek);
	int (*ssl_write_bytes)(SSL *s, int type, const void *buf_, int len);
	int (*ssl_dispatch_alert)(SSL *s);
	long (*ssl_ctrl)(SSL *s,int cmd,long larg,void *parg);
	long (*ssl_ctx_ctrl)(SSL_CTX *ctx,int cmd,long larg,void *parg);
	const SSL_CIPHER *(*get_cipher_by_char)(const unsigned char *ptr);
	int (*put_cipher_by_char)(const SSL_CIPHER *cipher,unsigned char *ptr);
	int (*ssl_pending)(const SSL *s);
	int (*num_ciphers)(void);
	const SSL_CIPHER *(*get_cipher)(unsigned ncipher);
	const struct ssl_method_st *(*get_ssl_method)(int version);
	long (*get_timeout)(void);
	struct ssl3_enc_method *ssl3_enc; /* Extra SSLv3/TLS stuff */
	int (*ssl_version)(void);
	long (*ssl_callback_ctrl)(SSL *s, int cb_id, void (*fp)(void));
	long (*ssl_ctx_callback_ctrl)(SSL_CTX *s, int cb_id, void (*fp)(void));
	};

/* Lets make this into an ASN.1 type structure as follows
 * SSL_SESSION_ID ::= SEQUENCE {
 *	version 		INTEGER,	-- structure version number
 *	SSLversion 		INTEGER,	-- SSL version number
 *	Cipher 			OCTET STRING,	-- the 3 byte cipher ID
 *	Session_ID 		OCTET STRING,	-- the Session ID
 *	Master_key 		OCTET STRING,	-- the master key
 *	KRB5_principal		OCTET STRING	-- optional Kerberos principal
 *	Key_Arg [ 0 ] IMPLICIT	OCTET STRING,	-- the optional Key argument
 *	Time [ 1 ] EXPLICIT	INTEGER,	-- optional Start Time
 *	Timeout [ 2 ] EXPLICIT	INTEGER,	-- optional Timeout ins seconds
 *	Peer [ 3 ] EXPLICIT	X509,		-- optional Peer Certificate
 *	Session_ID_context [ 4 ] EXPLICIT OCTET STRING,   -- the Session ID context
 *	Verify_result [ 5 ] EXPLICIT INTEGER,   -- X509_V_... code for `Peer'
 *	HostName [ 6 ] EXPLICIT OCTET STRING,   -- optional HostName from servername TLS extension 
 *	PSK_identity_hint [ 7 ] EXPLICIT OCTET STRING, -- optional PSK identity hint
 *	PSK_identity [ 8 ] EXPLICIT OCTET STRING,  -- optional PSK identity
 *	Ticket_lifetime_hint [9] EXPLICIT INTEGER, -- server's lifetime hint for session ticket
 *	Ticket [10]             EXPLICIT OCTET STRING, -- session ticket (clients only)
 *	Compression_meth [11]   EXPLICIT OCTET STRING, -- optional compression method
 *	SRP_username [ 12 ] EXPLICIT OCTET STRING -- optional SRP username
 *	}
 * Look in ssl/ssl_asn1.c for more details
 * I'm using EXPLICIT tags so I can read the damn things using asn1parse :-).
 */
struct ssl_session_st
	{
	int ssl_version;	/* what ssl version session info is
				 * being kept in here? */

	/* only really used in SSLv2 */
	unsigned int key_arg_length;
	unsigned char key_arg[SSL_MAX_KEY_ARG_LENGTH];
	int master_key_length;
	unsigned char master_key[SSL_MAX_MASTER_KEY_LENGTH];
	/* session_id - valid? */
	unsigned int session_id_length;
	unsigned char session_id[SSL_MAX_SSL_SESSION_ID_LENGTH];
	/* this is used to determine whether the session is being reused in
	 * the appropriate context. It is up to the application to set this,
	 * via SSL_new */
	unsigned int sid_ctx_length;
	unsigned char sid_ctx[SSL_MAX_SID_CTX_LENGTH];

#ifndef OPENSSL_NO_KRB5
        unsigned int krb5_client_princ_len;
        unsigned char krb5_client_princ[SSL_MAX_KRB5_PRINCIPAL_LENGTH];
#endif /* OPENSSL_NO_KRB5 */
#ifndef OPENSSL_NO_PSK
	char *psk_identity_hint;
	char *psk_identity;
#endif
	/* Used to indicate that session resumption is not allowed.
	 * Applications can also set this bit for a new session via
	 * not_resumable_session_cb to disable session caching and tickets. */
	int not_resumable;

	/* The cert is the certificate used to establish this connection */
	struct sess_cert_st /* SESS_CERT */ *sess_cert;

	/* This is the cert for the other end.
	 * On clients, it will be the same as sess_cert->peer_key->x509
	 * (the latter is not enough as sess_cert is not retained
	 * in the external representation of sessions, see ssl_asn1.c). */
	X509 *peer;
	/* when app_verify_callback accepts a session where the peer's certificate
	 * is not ok, we must remember the error for session reuse: */
	long verify_result; /* only for servers */

	int references;
	long timeout;
	long time;

	unsigned int compress_meth;	/* Need to lookup the method */

	const SSL_CIPHER *cipher;
	unsigned long cipher_id;	/* when ASN.1 loaded, this
					 * needs to be used to load
					 * the 'cipher' structure */

	STACK_OF(SSL_CIPHER) *ciphers; /* shared ciphers? */

	CRYPTO_EX_DATA ex_data; /* application specific data */

	/* These are used to make removal of session-ids more
	 * efficient and to implement a maximum cache size. */
	struct ssl_session_st *prev,*next;
#ifndef OPENSSL_NO_TLSEXT
	char *tlsext_hostname;
#ifndef OPENSSL_NO_EC
	size_t tlsext_ecpointformatlist_length;
	unsigned char *tlsext_ecpointformatlist; /* peer's list */
	size_t tlsext_ellipticcurvelist_length;
	unsigned char *tlsext_ellipticcurvelist; /* peer's list */
#endif /* OPENSSL_NO_EC */
	/* RFC4507 info */
	unsigned char *tlsext_tick;	/* Session ticket */
	size_t tlsext_ticklen;		/* Session ticket length */
	long tlsext_tick_lifetime_hint;	/* Session lifetime hint in seconds */
#endif
#ifndef OPENSSL_NO_SRP
	char *srp_username;
#endif
	};

#endif

#define SSL_OP_MICROSOFT_SESS_ID_BUG			0x00000001L
#define SSL_OP_NETSCAPE_CHALLENGE_BUG			0x00000002L
/* Allow initial connection to servers that don't support RI */
#define SSL_OP_LEGACY_SERVER_CONNECT			0x00000004L
#define SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG		0x00000008L
#define SSL_OP_SSLREF2_REUSE_CERT_TYPE_BUG		0x00000010L
#define SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER		0x00000020L
#define SSL_OP_SAFARI_ECDHE_ECDSA_BUG			0x00000040L
#define SSL_OP_SSLEAY_080_CLIENT_DH_BUG			0x00000080L
#define SSL_OP_TLS_D5_BUG				0x00000100L
#define SSL_OP_TLS_BLOCK_PADDING_BUG			0x00000200L

/* Disable SSL 3.0/TLS 1.0 CBC vulnerability workaround that was added
 * in OpenSSL 0.9.6d.  Usually (depending on the application protocol)
 * the workaround is not needed.  Unfortunately some broken SSL/TLS
 * implementations cannot handle it at all, which is why we include
 * it in SSL_OP_ALL. */
#define SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS              0x00000800L /* added in 0.9.6e */

/* SSL_OP_ALL: various bug workarounds that should be rather harmless.
 *             This used to be 0x000FFFFFL before 0.9.7. */
#define SSL_OP_ALL					0x80000BFFL

/* DTLS options */
#define SSL_OP_NO_QUERY_MTU                 0x00001000L
/* Turn on Cookie Exchange (on relevant for servers) */
#define SSL_OP_COOKIE_EXCHANGE              0x00002000L
/* Don't use RFC4507 ticket extension */
#define SSL_OP_NO_TICKET	            0x00004000L
/* Use Cisco's "speshul" version of DTLS_BAD_VER (as client)  */
#define SSL_OP_CISCO_ANYCONNECT		    0x00008000L

/* As server, disallow session resumption on renegotiation */
#define SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION	0x00010000L
/* Don't use compression even if supported */
#define SSL_OP_NO_COMPRESSION				0x00020000L
/* Permit unsafe legacy renegotiation */
#define SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION	0x00040000L
/* If set, always create a new key when using tmp_ecdh parameters */
#define SSL_OP_SINGLE_ECDH_USE				0x00080000L
/* If set, always create a new key when using tmp_dh parameters */
#define SSL_OP_SINGLE_DH_USE				0x00100000L
/* Set to always use the tmp_rsa key when doing RSA operations,
 * even when this violates protocol specs */
#define SSL_OP_EPHEMERAL_RSA				0x00200000L
/* Set on servers to choose the cipher according to the server's
 * preferences */
#define SSL_OP_CIPHER_SERVER_PREFERENCE			0x00400000L
/* If set, a server will allow a client to issue a SSLv3.0 version number
 * as latest version supported in the premaster secret, even when TLSv1.0
 * (version 3.1) was announced in the client hello. Normally this is
 * forbidden to prevent version rollback attacks. */
#define SSL_OP_TLS_ROLLBACK_BUG				0x00800000L

#define SSL_OP_NO_SSLv2					0x01000000L
#define SSL_OP_NO_SSLv3					0x02000000L
#define SSL_OP_NO_TLSv1					0x04000000L
#define SSL_OP_NO_TLSv1_2				0x08000000L
#define SSL_OP_NO_TLSv1_1				0x10000000L

#define SSL_OP_NO_DTLSv1				0x04000000L
#define SSL_OP_NO_DTLSv1_2				0x08000000L

#define SSL_OP_NO_SSL_MASK (SSL_OP_NO_SSLv2|SSL_OP_NO_SSLv3|\
	SSL_OP_NO_TLSv1|SSL_OP_NO_TLSv1_1|SSL_OP_NO_TLSv1_2)

/* These next two were never actually used for anything since SSLeay
 * zap so we have some more flags.
 */
/* The next flag deliberately changes the ciphertest, this is a check
 * for the PKCS#1 attack */
#define SSL_OP_PKCS1_CHECK_1				0x0
#define SSL_OP_PKCS1_CHECK_2				0x0

#define SSL_OP_NETSCAPE_CA_DN_BUG			0x20000000L
#define SSL_OP_NETSCAPE_DEMO_CIPHER_CHANGE_BUG		0x40000000L
/* Make server add server-hello extension from early version of
 * cryptopro draft, when GOST ciphersuite is negotiated. 
 * Required for interoperability with CryptoPro CSP 3.x 
 */
#define SSL_OP_CRYPTOPRO_TLSEXT_BUG			0x80000000L

/* Allow SSL_write(..., n) to return r with 0 < r < n (i.e. report success
 * when just a single record has been written): */
#define SSL_MODE_ENABLE_PARTIAL_WRITE       0x00000001L
/* Make it possible to retry SSL_write() with changed buffer location
 * (buffer contents must stay the same!); this is not the default to avoid
 * the misconception that non-blocking SSL_write() behaves like
 * non-blocking write(): */
#define SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER 0x00000002L
/* Never bother the application with retries if the transport
 * is blocking: */
#define SSL_MODE_AUTO_RETRY 0x00000004L
/* Don't attempt to automatically build certificate chain */
#define SSL_MODE_NO_AUTO_CHAIN 0x00000008L
/* Save RAM by releasing read and write buffers when they're empty. (SSL3 and
 * TLS only.)  "Released" buffers are put onto a free-list in the context
 * or just freed (depending on the context's setting for freelist_max_len). */
#define SSL_MODE_RELEASE_BUFFERS 0x00000010L

/* Cert related flags */
/* Many implementations ignore some aspects of the TLS standards such as
 * enforcing certifcate chain algorithms. When this is set we enforce them.
 */
#define SSL_CERT_FLAG_TLS_STRICT		0x00000001L

/* Suite B modes, takes same values as certificate verify flags */
#define SSL_CERT_FLAG_SUITEB_128_LOS_ONLY	0x10000
/* Suite B 192 bit only mode */
#define SSL_CERT_FLAG_SUITEB_192_LOS		0x20000
/* Suite B 128 bit mode allowing 192 bit algorithms */
#define SSL_CERT_FLAG_SUITEB_128_LOS		0x30000

/* Perform all sorts of protocol violations for testing purposes */
#define SSL_CERT_FLAG_BROKEN_PROTOCOL		0x10000000

/* Flags for building certificate chains */
/* Treat any existing certificates as untrusted CAs */
#define SSL_BUILD_CHAIN_FLAG_UNTRUSTED	0x1
/* Don't include root CA in chain */
#define SSL_BUILD_CHAIN_FLAG_NO_ROOT	0x2

/* Flags returned by SSL_check_chain */
/* Certificate can be used with this session */
#define CERT_PKEY_VALID		0x1
/* Certificate can also be used for signing */
#define CERT_PKEY_SIGN		0x2
/* EE certificate signing algorithm OK */
#define CERT_PKEY_EE_SIGNATURE	0x10
/* CA signature algorithms OK */
#define CERT_PKEY_CA_SIGNATURE	0x20
/* EE certificate parameters OK */
#define CERT_PKEY_EE_PARAM	0x40
/* CA certificate parameters OK */
#define CERT_PKEY_CA_PARAM	0x80
/* Signing explicitly allowed as opposed to SHA1 fallback */
#define CERT_PKEY_EXPLICIT_SIGN	0x100
/* Client CA issuer names match (always set for server cert) */
#define CERT_PKEY_ISSUER_NAME	0x200
/* Cert type matches client types (always set for server cert) */
#define CERT_PKEY_CERT_TYPE	0x400
/* Cert chain suitable to Suite B */
#define CERT_PKEY_SUITEB	0x800

#define SSL_CONF_FLAG_CMDLINE		0x1
#define SSL_CONF_FLAG_FILE		0x2
#define SSL_CONF_FLAG_CLIENT		0x4
#define SSL_CONF_FLAG_SERVER		0x8
#define SSL_CONF_FLAG_SHOW_ERRORS	0x10
#define SSL_CONF_FLAG_CERTIFICATE	0x20
/* Configuration value types */
#define SSL_CONF_TYPE_UNKNOWN		0x0
#define SSL_CONF_TYPE_STRING		0x1
#define SSL_CONF_TYPE_FILE		0x2
#define SSL_CONF_TYPE_DIR		0x3

/* Note: SSL[_CTX]_set_{options,mode} use |= op on the previous value,
 * they cannot be used to clear bits. */

#define SSL_CTX_set_options(ctx,op) \
	SSL_CTX_ctrl((ctx),SSL_CTRL_OPTIONS,(op),NULL)
#define SSL_CTX_clear_options(ctx,op) \
	SSL_CTX_ctrl((ctx),SSL_CTRL_CLEAR_OPTIONS,(op),NULL)
#define SSL_CTX_get_options(ctx) \
	SSL_CTX_ctrl((ctx),SSL_CTRL_OPTIONS,0,NULL)
#define SSL_set_options(ssl,op) \
	SSL_ctrl((ssl),SSL_CTRL_OPTIONS,(op),NULL)
#define SSL_clear_options(ssl,op) \
	SSL_ctrl((ssl),SSL_CTRL_CLEAR_OPTIONS,(op),NULL)
#define SSL_get_options(ssl) \
        SSL_ctrl((ssl),SSL_CTRL_OPTIONS,0,NULL)

#define SSL_CTX_set_mode(ctx,op) \
	SSL_CTX_ctrl((ctx),SSL_CTRL_MODE,(op),NULL)
#define SSL_CTX_clear_mode(ctx,op) \
	SSL_CTX_ctrl((ctx),SSL_CTRL_CLEAR_MODE,(op),NULL)
#define SSL_CTX_get_mode(ctx) \
	SSL_CTX_ctrl((ctx),SSL_CTRL_MODE,0,NULL)
#define SSL_clear_mode(ssl,op) \
	SSL_ctrl((ssl),SSL_CTRL_CLEAR_MODE,(op),NULL)
#define SSL_set_mode(ssl,op) \
	SSL_ctrl((ssl),SSL_CTRL_MODE,(op),NULL)
#define SSL_get_mode(ssl) \
        SSL_ctrl((ssl),SSL_CTRL_MODE,0,NULL)
#define SSL_set_mtu(ssl, mtu) \
        SSL_ctrl((ssl),SSL_CTRL_SET_MTU,(mtu),NULL)

#define SSL_get_secure_renegotiation_support(ssl) \
	SSL_ctrl((ssl), SSL_CTRL_GET_RI_SUPPORT, 0, NULL)

#ifndef OPENSSL_NO_HEARTBEATS
#define SSL_heartbeat(ssl) \
        SSL_ctrl((ssl),SSL_CTRL_TLS_EXT_SEND_HEARTBEAT,0,NULL)
#endif

#define SSL_CTX_set_cert_flags(ctx,op) \
	SSL_CTX_ctrl((ctx),SSL_CTRL_CERT_FLAGS,(op),NULL)
#define SSL_set_cert_flags(s,op) \
	SSL_ctrl((s),SSL_CTRL_CERT_FLAGS,(op),NULL)
#define SSL_CTX_clear_cert_flags(ctx,op) \
	SSL_CTX_ctrl((ctx),SSL_CTRL_CLEAR_CERT_FLAGS,(op),NULL)
#define SSL_clear_cert_flags(s,op) \
	SSL_ctrl((s),SSL_CTRL_CLEAR_CERT_FLAGS,(op),NULL)

void SSL_CTX_set_msg_callback(SSL_CTX *ctx, void (*cb)(int write_p, int version, int content_type, const void *buf, size_t len, SSL *ssl, void *arg));
void SSL_set_msg_callback(SSL *ssl, void (*cb)(int write_p, int version, int content_type, const void *buf, size_t len, SSL *ssl, void *arg));
#define SSL_CTX_set_msg_callback_arg(ctx, arg) SSL_CTX_ctrl((ctx), SSL_CTRL_SET_MSG_CALLBACK_ARG, 0, (arg))
#define SSL_set_msg_callback_arg(ssl, arg) SSL_ctrl((ssl), SSL_CTRL_SET_MSG_CALLBACK_ARG, 0, (arg))

#ifndef OPENSSL_NO_SRP

#ifndef OPENSSL_NO_SSL_INTERN

typedef struct srp_ctx_st
	{
	/* param for all the callbacks */
	void *SRP_cb_arg;
	/* set client Hello login callback */
	int (*TLS_ext_srp_username_callback)(SSL *, int *, void *);
	/* set SRP N/g param callback for verification */
	int (*SRP_verify_param_callback)(SSL *, void *);
	/* set SRP client passwd callback */
	char *(*SRP_give_srp_client_pwd_callback)(SSL *, void *);

	char *login;
	BIGNUM *N,*g,*s,*B,*A;
	BIGNUM *a,*b,*v;
	char *info;
	int strength;

	unsigned long srp_Mask;
	} SRP_CTX;

#endif

/* see tls_srp.c */
int SSL_SRP_CTX_init(SSL *s);
int SSL_CTX_SRP_CTX_init(SSL_CTX *ctx);
int SSL_SRP_CTX_free(SSL *ctx);
int SSL_CTX_SRP_CTX_free(SSL_CTX *ctx);
int SSL_srp_server_param_with_username(SSL *s, int *ad);
int SRP_generate_server_master_secret(SSL *s,unsigned char *master_key);
int SRP_Calc_A_param(SSL *s);
int SRP_generate_client_master_secret(SSL *s,unsigned char *master_key);

#endif

#if defined(OPENSSL_SYS_MSDOS) && !defined(OPENSSL_SYS_WIN32)
#define SSL_MAX_CERT_LIST_DEFAULT 1024*30 /* 30k max cert list :-) */
#else
#define SSL_MAX_CERT_LIST_DEFAULT 1024*100 /* 100k max cert list :-) */
#endif

#define SSL_SESSION_CACHE_MAX_SIZE_DEFAULT	(1024*20)

/* This callback type is used inside SSL_CTX, SSL, and in the functions that set
 * them. It is used to override the generation of SSL/TLS session IDs in a
 * server. Return value should be zero on an error, non-zero to proceed. Also,
 * callbacks should themselves check if the id they generate is unique otherwise
 * the SSL handshake will fail with an error - callbacks can do this using the
 * 'ssl' value they're passed by;
 *      SSL_has_matching_session_id(ssl, id, *id_len)
 * The length value passed in is set at the maximum size the session ID can be.
 * In SSLv2 this is 16 bytes, whereas SSLv3/TLSv1 it is 32 bytes. The callback
 * can alter this length to be less if desired, but under SSLv2 session IDs are
 * supposed to be fixed at 16 bytes so the id will be padded after the callback
 * returns in this case. It is also an error for the callback to set the size to
 * zero. */
typedef int (*GEN_SESSION_CB)(const SSL *ssl, unsigned char *id,
				unsigned int *id_len);

typedef struct ssl_comp_st SSL_COMP;

#ifndef OPENSSL_NO_SSL_INTERN

struct ssl_comp_st
	{
	int id;
	const char *name;
#ifndef OPENSSL_NO_COMP
	COMP_METHOD *method;
#else
	char *method;
#endif
	};

DECLARE_STACK_OF(SSL_COMP)
DECLARE_LHASH_OF(SSL_SESSION);

struct ssl_ctx_st
	{
	const SSL_METHOD *method;

	STACK_OF(SSL_CIPHER) *cipher_list;
	/* same as above but sorted for lookup */
	STACK_OF(SSL_CIPHER) *cipher_list_by_id;

	struct x509_store_st /* X509_STORE */ *cert_store;
	LHASH_OF(SSL_SESSION) *sessions;
	/* Most session-ids that will be cached, default is
	 * SSL_SESSION_CACHE_MAX_SIZE_DEFAULT. 0 is unlimited. */
	unsigned long session_cache_size;
	struct ssl_session_st *session_cache_head;
	struct ssl_session_st *session_cache_tail;

	/* This can have one of 2 values, ored together,
	 * SSL_SESS_CACHE_CLIENT,
	 * SSL_SESS_CACHE_SERVER,
	 * Default is SSL_SESSION_CACHE_SERVER, which means only
	 * SSL_accept which cache SSL_SESSIONS. */
	int session_cache_mode;

	/* If timeout is not 0, it is the default timeout value set
	 * when SSL_new() is called.  This has been put in to make
	 * life easier to set things up */
	long session_timeout;

	/* If this callback is not null, it will be called each
	 * time a session id is added to the cache.  If this function
	 * returns 1, it means that the callback will do a
	 * SSL_SESSION_free() when it has finished using it.  Otherwise,
	 * on 0, it means the callback has finished with it.
	 * If remove_session_cb is not null, it will be called when
	 * a session-id is removed from the cache.  After the call,
	 * OpenSSL will SSL_SESSION_free() it. */
	int (*new_session_cb)(struct ssl_st *ssl,SSL_SESSION *sess);
	void (*remove_session_cb)(struct ssl_ctx_st *ctx,SSL_SESSION *sess);
	SSL_SESSION *(*get_session_cb)(struct ssl_st *ssl,
		unsigned char *data,int len,int *copy);

	struct
		{
		int sess_connect;	/* SSL new conn - started */
		int sess_connect_renegotiate;/* SSL reneg - requested */
		int sess_connect_good;	/* SSL new conne/reneg - finished */
		int sess_accept;	/* SSL new accept - started */
		int sess_accept_renegotiate;/* SSL reneg - requested */
		int sess_accept_good;	/* SSL accept/reneg - finished */
		int sess_miss;		/* session lookup misses  */
		int sess_timeout;	/* reuse attempt on timeouted session */
		int sess_cache_full;	/* session removed due to full cache */
		int sess_hit;		/* session reuse actually done */
		int sess_cb_hit;	/* session-id that was not
					 * in the cache was
					 * passed back via the callback.  This