ssl_lib.c

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/*! \file ssl/ssl_lib.c
 *  \brief Version independent SSL functions.
 */
/* Copyright (C) 1995-1998 Eric Young ([e-mail])
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young ([e-mail]).
 * 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 ([e-mail]).
 * 
 * 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 ([e-mail])"
 *    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 ([e-mail])"
 * 
 * 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.]
 */


#include <assert.h>
#include <stdio.h>
#include <openssl/objects.h>
#include <openssl/lhash.h>
#include <openssl/x509v3.h>
#include "ssl_locl.h"

const char *SSL_version_str=OPENSSL_VERSION_TEXT;

static STACK_OF(CRYPTO_EX_DATA_FUNCS) *ssl_meth=NULL;
static STACK_OF(CRYPTO_EX_DATA_FUNCS) *ssl_ctx_meth=NULL;
static int ssl_meth_num=0;
static int ssl_ctx_meth_num=0;

OPENSSL_GLOBAL SSL3_ENC_METHOD ssl3_undef_enc_method={
	/* evil casts, but these functions are only called if there's a library bug */
	(int (*)(SSL *,int))ssl_undefined_function,
	(int (*)(SSL *, unsigned char *, int))ssl_undefined_function,
	ssl_undefined_function,
	(int (*)(SSL *, unsigned char *, unsigned char *, int))ssl_undefined_function,
	(int (*)(SSL*, int))ssl_undefined_function,
	(int (*)(SSL *, EVP_MD_CTX *, EVP_MD_CTX *, const char*, int, unsigned char *))ssl_undefined_function
	};

int SSL_clear(SSL *s)
	{
	int state;

	if (s->method == NULL)
		{
		SSLerr(SSL_F_SSL_CLEAR,SSL_R_NO_METHOD_SPECIFIED);
		return(0);
		}

	s->error=0;
	s->hit=0;
	s->shutdown=0;

#if 0 /* Disabled since version 1.10 of this file (early return not
       * needed because SSL_clear is not called when doing renegotiation) */
	/* This is set if we are doing dynamic renegotiation so keep
	 * the old cipher.  It is sort of a SSL_clear_lite :-) */
	if (s->new_session) return(1);
#else
	if (s->new_session)
		{
		SSLerr(SSL_F_SSL_CLEAR,SSL_R_INTERNAL_ERROR);
		return 0;
		}
#endif

	state=s->state; /* Keep to check if we throw away the session-id */
	s->type=0;

	s->state=SSL_ST_BEFORE|((s->server)?SSL_ST_ACCEPT:SSL_ST_CONNECT);

	s->version=s->method->version;
	s->client_version=s->version;
	s->rwstate=SSL_NOTHING;
	s->rstate=SSL_ST_READ_HEADER;
	s->read_ahead=s->ctx->read_ahead;

	if (s->init_buf != NULL)
		{
		BUF_MEM_free(s->init_buf);
		s->init_buf=NULL;
		}

	ssl_clear_cipher_ctx(s);

	if (ssl_clear_bad_session(s))
		{
		SSL_SESSION_free(s->session);
		s->session=NULL;
		}

	s->first_packet=0;

#if 1
	/* Check to see if we were changed into a different method, if
	 * so, revert back if we are not doing session-id reuse. */
	if ((s->session == NULL) && (s->method != s->ctx->method))
		{
		s->method->ssl_free(s);
		s->method=s->ctx->method;
		if (!s->method->ssl_new(s))
			return(0);
		}
	else
#endif
		s->method->ssl_clear(s);
	return(1);
	}

/** Used to change an SSL_CTXs default SSL method type */
int SSL_CTX_set_ssl_version(SSL_CTX *ctx,SSL_METHOD *meth)
	{
	STACK_OF(SSL_CIPHER) *sk;

	ctx->method=meth;

	sk=ssl_create_cipher_list(ctx->method,&(ctx->cipher_list),
		&(ctx->cipher_list_by_id),SSL_DEFAULT_CIPHER_LIST);
	if ((sk == NULL) || (sk_SSL_CIPHER_num(sk) <= 0))
		{
		SSLerr(SSL_F_SSL_CTX_SET_SSL_VERSION,SSL_R_SSL_LIBRARY_HAS_NO_CIPHERS);
		return(0);
		}
	return(1);
	}

SSL *SSL_new(SSL_CTX *ctx)
	{
	SSL *s;

	if (ctx == NULL)
		{
		SSLerr(SSL_F_SSL_NEW,SSL_R_NULL_SSL_CTX);
		return(NULL);
		}
	if (ctx->method == NULL)
		{
		SSLerr(SSL_F_SSL_NEW,SSL_R_SSL_CTX_HAS_NO_DEFAULT_SSL_VERSION);
		return(NULL);
		}

	s=(SSL *)OPENSSL_malloc(sizeof(SSL));
	if (s == NULL) goto err;
	memset(s,0,sizeof(SSL));

	if (ctx->cert != NULL)
		{
		/* Earlier library versions used to copy the pointer to
		 * the CERT, not its contents; only when setting new
		 * parameters for the per-SSL copy, ssl_cert_new would be
		 * called (and the direct reference to the per-SSL_CTX
		 * settings would be lost, but those still were indirectly
		 * accessed for various purposes, and for that reason they
		 * used to be known as s->ctx->default_cert).
		 * Now we don't look at the SSL_CTX's CERT after having
		 * duplicated it once. */

		s->cert = ssl_cert_dup(ctx->cert);
		if (s->cert == NULL)
			goto err;
		}
	else
		s->cert=NULL; /* Cannot really happen (see SSL_CTX_new) */
	s->sid_ctx_length=ctx->sid_ctx_length;
	memcpy(&s->sid_ctx,&ctx->sid_ctx,sizeof(s->sid_ctx));
	s->verify_mode=ctx->verify_mode;
	s->verify_depth=ctx->verify_depth;
	s->verify_callback=ctx->default_verify_callback;
	s->purpose = ctx->purpose;
	s->trust = ctx->trust;
	CRYPTO_add(&ctx->references,1,CRYPTO_LOCK_SSL_CTX);
	s->ctx=ctx;

	s->verify_result=X509_V_OK;

	s->method=ctx->method;

	if (!s->method->ssl_new(s))
		goto err;

	s->quiet_shutdown=ctx->quiet_shutdown;
	s->references=1;
	s->server=(ctx->method->ssl_accept == ssl_undefined_function)?0:1;
	s->options=ctx->options;
	s->mode=ctx->mode;
	SSL_clear(s);

	CRYPTO_new_ex_data(ssl_meth,s,&s->ex_data);

	return(s);
err:
	if (s != NULL)
		{
		if (s->cert != NULL)
			ssl_cert_free(s->cert);
		if (s->ctx != NULL)
			SSL_CTX_free(s->ctx); /* decrement reference count */
		OPENSSL_free(s);
		}
	SSLerr(SSL_F_SSL_NEW,ERR_R_MALLOC_FAILURE);
	return(NULL);
	}

int SSL_CTX_set_session_id_context(SSL_CTX *ctx,const unsigned char *sid_ctx,
				   unsigned int sid_ctx_len)
    {
    if(sid_ctx_len > SSL_MAX_SID_CTX_LENGTH)
	{
	SSLerr(SSL_F_SSL_CTX_SET_SESSION_ID_CONTEXT,SSL_R_SSL_SESSION_ID_CONTEXT_TOO_LONG);
	return 0;
	}
    ctx->sid_ctx_length=sid_ctx_len;
    memcpy(ctx->sid_ctx,sid_ctx,sid_ctx_len);

    return 1;
    }

int SSL_set_session_id_context(SSL *ssl,const unsigned char *sid_ctx,
			       unsigned int sid_ctx_len)
    {
    if(sid_ctx_len > SSL_MAX_SID_CTX_LENGTH)
	{
	SSLerr(SSL_F_SSL_SET_SESSION_ID_CONTEXT,SSL_R_SSL_SESSION_ID_CONTEXT_TOO_LONG);
	return 0;
	}
    ssl->sid_ctx_length=sid_ctx_len;
    memcpy(ssl->sid_ctx,sid_ctx,sid_ctx_len);

    return 1;
    }

int SSL_CTX_set_purpose(SSL_CTX *s, int purpose)
{
	if(X509_PURPOSE_get_by_id(purpose) == -1) {
		SSLerr(SSL_F_SSL_CTX_SET_PURPOSE, SSL_R_INVALID_PURPOSE);
		return 0;
	}
	s->purpose = purpose;
	return 1;
}

int SSL_set_purpose(SSL *s, int purpose)
{
	if(X509_PURPOSE_get_by_id(purpose) == -1) {
		SSLerr(SSL_F_SSL_SET_PURPOSE, SSL_R_INVALID_PURPOSE);
		return 0;
	}
	s->purpose = purpose;
	return 1;
}
	
int SSL_CTX_set_trust(SSL_CTX *s, int trust)
{
	if(X509_TRUST_get_by_id(trust) == -1) {
		SSLerr(SSL_F_SSL_CTX_SET_TRUST, SSL_R_INVALID_TRUST);
		return 0;
	}
	s->trust = trust;
	return 1;
}

int SSL_set_trust(SSL *s, int trust)
{
	if(X509_TRUST_get_by_id(trust) == -1) {
		SSLerr(SSL_F_SSL_SET_TRUST, SSL_R_INVALID_TRUST);
		return 0;
	}
	s->trust = trust;
	return 1;
}

void SSL_free(SSL *s)
	{
	int i;

	if(s == NULL)
	    return;

	i=CRYPTO_add(&s->references,-1,CRYPTO_LOCK_SSL);
#ifdef REF_PRINT
	REF_PRINT("SSL",s);
#endif
	if (i > 0) return;
#ifdef REF_CHECK
	if (i < 0)
		{
		fprintf(stderr,"SSL_free, bad reference count\n");
		abort(); /* ok */
		}
#endif

	CRYPTO_free_ex_data(ssl_meth,(char *)s,&s->ex_data);

	if (s->bbio != NULL)
		{
		/* If the buffering BIO is in place, pop it off */
		if (s->bbio == s->wbio)
			{
			s->wbio=BIO_pop(s->wbio);
			}
		BIO_free(s->bbio);
		s->bbio=NULL;
		}
	if (s->rbio != NULL)
		BIO_free_all(s->rbio);
	if ((s->wbio != NULL) && (s->wbio != s->rbio))
		BIO_free_all(s->wbio);

	if (s->init_buf != NULL) BUF_MEM_free(s->init_buf);

	/* add extra stuff */
	if (s->cipher_list != NULL) sk_SSL_CIPHER_free(s->cipher_list);
	if (s->cipher_list_by_id != NULL) sk_SSL_CIPHER_free(s->cipher_list_by_id);

	/* Make the next call work :-) */
	if (s->session != NULL)
		{
		ssl_clear_bad_session(s);
		SSL_SESSION_free(s->session);
		}

	ssl_clear_cipher_ctx(s);

	if (s->cert != NULL) ssl_cert_free(s->cert);
	/* Free up if allocated */

	if (s->ctx) SSL_CTX_free(s->ctx);

	if (s->client_CA != NULL)
		sk_X509_NAME_pop_free(s->client_CA,X509_NAME_free);

	if (s->method != NULL) s->method->ssl_free(s);

	OPENSSL_free(s);
	}

void SSL_set_bio(SSL *s,BIO *rbio,BIO *wbio)
	{
	/* If the output buffering BIO is still in place, remove it
	 */
	if (s->bbio != NULL)
		{
		if (s->wbio == s->bbio)
			{
			s->wbio=s->wbio->next_bio;
			s->bbio->next_bio=NULL;
			}
		}
	if ((s->rbio != NULL) && (s->rbio != rbio))
		BIO_free_all(s->rbio);
	if ((s->wbio != NULL) && (s->wbio != wbio) && (s->rbio != s->wbio))
		BIO_free_all(s->wbio);
	s->rbio=rbio;
	s->wbio=wbio;
	}

BIO *SSL_get_rbio(SSL *s)
	{ return(s->rbio); }

BIO *SSL_get_wbio(SSL *s)
	{ return(s->wbio); }

int SSL_get_fd(SSL *s)
	{
	int ret= -1;
	BIO *b,*r;

	b=SSL_get_rbio(s);
	r=BIO_find_type(b,BIO_TYPE_DESCRIPTOR);
	if (r != NULL)
		BIO_get_fd(r,&ret);
	return(ret);
	}

#ifndef NO_SOCK
int SSL_set_fd(SSL *s,int fd)
	{
	int ret=0;
	BIO *bio=NULL;

	bio=BIO_new(BIO_s_socket());

	if (bio == NULL)
		{
		SSLerr(SSL_F_SSL_SET_FD,ERR_R_BUF_LIB);
		goto err;
		}
	BIO_set_fd(bio,fd,BIO_NOCLOSE);
	SSL_set_bio(s,bio,bio);
	ret=1;
err:
	return(ret);
	}

int SSL_set_wfd(SSL *s,int fd)
	{
	int ret=0;
	BIO *bio=NULL;

	if ((s->rbio == NULL) || (BIO_method_type(s->rbio) != BIO_TYPE_SOCKET)
		|| ((int)BIO_get_fd(s->rbio,NULL) != fd))
		{
		bio=BIO_new(BIO_s_socket());

		if (bio == NULL)
			{ SSLerr(SSL_F_SSL_SET_WFD,ERR_R_BUF_LIB); goto err; }
		BIO_set_fd(bio,fd,BIO_NOCLOSE);
		SSL_set_bio(s,SSL_get_rbio(s),bio);
		}
	else
		SSL_set_bio(s,SSL_get_rbio(s),SSL_get_rbio(s));
	ret=1;
err:
	return(ret);
	}

int SSL_set_rfd(SSL *s,int fd)
	{
	int ret=0;
	BIO *bio=NULL;

	if ((s->wbio == NULL) || (BIO_method_type(s->wbio) != BIO_TYPE_SOCKET)
		|| ((int)BIO_get_fd(s->wbio,NULL) != fd))
		{
		bio=BIO_new(BIO_s_socket());

		if (bio == NULL)
			{
			SSLerr(SSL_F_SSL_SET_RFD,ERR_R_BUF_LIB);
			goto err;
			}
		BIO_set_fd(bio,fd,BIO_NOCLOSE);
		SSL_set_bio(s,bio,SSL_get_wbio(s));
		}
	else
		SSL_set_bio(s,SSL_get_wbio(s),SSL_get_wbio(s));
	ret=1;
err:
	return(ret);
	}
#endif


/* return length of latest Finished message we sent, copy to 'buf' */
size_t SSL_get_finished(SSL *s, void *buf, size_t count)
	{
	size_t ret = 0;
	
	if (s->s3 != NULL)
		{
		ret = s->s3->tmp.finish_md_len;
		if (count > ret)
			count = ret;
		memcpy(buf, s->s3->tmp.finish_md, count);
		}
	return ret;
	}

/* return length of latest Finished message we expected, copy to 'buf' */
size_t SSL_get_peer_finished(SSL *s, void *buf, size_t count)
	{
	size_t ret = 0;
	
	if (s->s3 != NULL)
		{
		ret = s->s3->tmp.peer_finish_md_len;
		if (count > ret)
			count = ret;
		memcpy(buf, s->s3->tmp.peer_finish_md, count);
		}