ssl_lib.c

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	CERT_PKEY *cpk;
	int rsa_enc,rsa_tmp,rsa_sign,dh_tmp,dh_rsa,dh_dsa,dsa_sign;
	int rsa_enc_export,dh_rsa_export,dh_dsa_export;
	int rsa_tmp_export,dh_tmp_export,kl;
	unsigned long mask,emask;
	int have_ecc_cert, ecdh_ok, ecdsa_ok, ecc_pkey_size;
#ifndef OPENSSL_NO_ECDH
	int have_ecdh_tmp;
#endif
	X509 *x = NULL;
	EVP_PKEY *ecc_pkey = NULL;
	int signature_nid = 0;

	if (c == NULL) return;

	kl=SSL_C_EXPORT_PKEYLENGTH(cipher);

#ifndef OPENSSL_NO_RSA
	rsa_tmp=(c->rsa_tmp != NULL || c->rsa_tmp_cb != NULL);
	rsa_tmp_export=(c->rsa_tmp_cb != NULL ||
		(rsa_tmp && RSA_size(c->rsa_tmp)*8 <= kl));
#else
	rsa_tmp=rsa_tmp_export=0;
#endif
#ifndef OPENSSL_NO_DH
	dh_tmp=(c->dh_tmp != NULL || c->dh_tmp_cb != NULL);
	dh_tmp_export=(c->dh_tmp_cb != NULL ||
		(dh_tmp && DH_size(c->dh_tmp)*8 <= kl));
#else
	dh_tmp=dh_tmp_export=0;
#endif

#ifndef OPENSSL_NO_ECDH
	have_ecdh_tmp=(c->ecdh_tmp != NULL || c->ecdh_tmp_cb != NULL);
#endif
	cpk= &(c->pkeys[SSL_PKEY_RSA_ENC]);
	rsa_enc= (cpk->x509 != NULL && cpk->privatekey != NULL);
	rsa_enc_export=(rsa_enc && EVP_PKEY_size(cpk->privatekey)*8 <= kl);
	cpk= &(c->pkeys[SSL_PKEY_RSA_SIGN]);
	rsa_sign=(cpk->x509 != NULL && cpk->privatekey != NULL);
	cpk= &(c->pkeys[SSL_PKEY_DSA_SIGN]);
	dsa_sign=(cpk->x509 != NULL && cpk->privatekey != NULL);
	cpk= &(c->pkeys[SSL_PKEY_DH_RSA]);
	dh_rsa=  (cpk->x509 != NULL && cpk->privatekey != NULL);
	dh_rsa_export=(dh_rsa && EVP_PKEY_size(cpk->privatekey)*8 <= kl);
	cpk= &(c->pkeys[SSL_PKEY_DH_DSA]);
/* FIX THIS EAY EAY EAY */
	dh_dsa=  (cpk->x509 != NULL && cpk->privatekey != NULL);
	dh_dsa_export=(dh_dsa && EVP_PKEY_size(cpk->privatekey)*8 <= kl);
	cpk= &(c->pkeys[SSL_PKEY_ECC]);
	have_ecc_cert= (cpk->x509 != NULL && cpk->privatekey != NULL);
	mask=0;
	emask=0;

#ifdef CIPHER_DEBUG
	printf("rt=%d rte=%d dht=%d re=%d ree=%d rs=%d ds=%d dhr=%d dhd=%d\n",
		rsa_tmp,rsa_tmp_export,dh_tmp,
		rsa_enc,rsa_enc_export,rsa_sign,dsa_sign,dh_rsa,dh_dsa);
#endif

	if (rsa_enc || (rsa_tmp && rsa_sign))
		mask|=SSL_kRSA;
	if (rsa_enc_export || (rsa_tmp_export && (rsa_sign || rsa_enc)))
		emask|=SSL_kRSA;

#if 0
	/* The match needs to be both kEDH and aRSA or aDSA, so don't worry */
	if (	(dh_tmp || dh_rsa || dh_dsa) && 
		(rsa_enc || rsa_sign || dsa_sign))
		mask|=SSL_kEDH;
	if ((dh_tmp_export || dh_rsa_export || dh_dsa_export) &&
		(rsa_enc || rsa_sign || dsa_sign))
		emask|=SSL_kEDH;
#endif

	if (dh_tmp_export) 
		emask|=SSL_kEDH;

	if (dh_tmp)
		mask|=SSL_kEDH;

	if (dh_rsa) mask|=SSL_kDHr;
	if (dh_rsa_export) emask|=SSL_kDHr;

	if (dh_dsa) mask|=SSL_kDHd;
	if (dh_dsa_export) emask|=SSL_kDHd;

	if (rsa_enc || rsa_sign)
		{
		mask|=SSL_aRSA;
		emask|=SSL_aRSA;
		}

	if (dsa_sign)
		{
		mask|=SSL_aDSS;
		emask|=SSL_aDSS;
		}

	mask|=SSL_aNULL;
	emask|=SSL_aNULL;

#ifndef OPENSSL_NO_KRB5
	mask|=SSL_kKRB5|SSL_aKRB5;
	emask|=SSL_kKRB5|SSL_aKRB5;
#endif

	/* An ECC certificate may be usable for ECDH and/or
	 * ECDSA cipher suites depending on the key usage extension.
	 */
	if (have_ecc_cert)
		{
                /* This call populates extension flags (ex_flags) */
		x = (c->pkeys[SSL_PKEY_ECC]).x509;
		X509_check_purpose(x, -1, 0);
		ecdh_ok = (x->ex_flags & EXFLAG_KUSAGE) ?
		    (x->ex_kusage & X509v3_KU_KEY_AGREEMENT) : 1;
		ecdsa_ok = (x->ex_flags & EXFLAG_KUSAGE) ?
		    (x->ex_kusage & X509v3_KU_DIGITAL_SIGNATURE) : 1;
		ecc_pkey = X509_get_pubkey(x);
		ecc_pkey_size = (ecc_pkey != NULL) ? 
		    EVP_PKEY_bits(ecc_pkey) : 0;
		EVP_PKEY_free(ecc_pkey);
		if ((x->sig_alg) && (x->sig_alg->algorithm))
			signature_nid = OBJ_obj2nid(x->sig_alg->algorithm);
#ifndef OPENSSL_NO_ECDH
		if (ecdh_ok)
			{
			if ((signature_nid == NID_md5WithRSAEncryption) ||
			    (signature_nid == NID_md4WithRSAEncryption) ||
			    (signature_nid == NID_md2WithRSAEncryption))
				{
				mask|=SSL_kECDH|SSL_aRSA;
				if (ecc_pkey_size <= 163)
					emask|=SSL_kECDH|SSL_aRSA;
				}
			if (signature_nid == NID_ecdsa_with_SHA1)
				{
				mask|=SSL_kECDH|SSL_aECDSA;
				if (ecc_pkey_size <= 163)
					emask|=SSL_kECDH|SSL_aECDSA;
				}
			}
#endif
#ifndef OPENSSL_NO_ECDSA
		if (ecdsa_ok)
			{
			mask|=SSL_aECDSA;
			emask|=SSL_aECDSA;
			}
#endif
		}

#ifndef OPENSSL_NO_ECDH
	if (have_ecdh_tmp)
		{
		mask|=SSL_kECDHE;
		emask|=SSL_kECDHE;
		}
#endif
	c->mask=mask;
	c->export_mask=emask;
	c->valid=1;
	}

/* This handy macro borrowed from crypto/x509v3/v3_purp.c */
#define ku_reject(x, usage) \
	(((x)->ex_flags & EXFLAG_KUSAGE) && !((x)->ex_kusage & (usage)))

int check_srvr_ecc_cert_and_alg(X509 *x, SSL_CIPHER *cs)
	{
	unsigned long alg = cs->algorithms;
	EVP_PKEY *pkey = NULL;
	int keysize = 0;
	int signature_nid = 0;

	if (SSL_C_IS_EXPORT(cs))
		{
		/* ECDH key length in export ciphers must be <= 163 bits */
		pkey = X509_get_pubkey(x);
		if (pkey == NULL) return 0;
		keysize = EVP_PKEY_bits(pkey);
		EVP_PKEY_free(pkey);
		if (keysize > 163) return 0;
		}

	/* This call populates the ex_flags field correctly */
	X509_check_purpose(x, -1, 0);
	if ((x->sig_alg) && (x->sig_alg->algorithm))
		signature_nid = OBJ_obj2nid(x->sig_alg->algorithm);
	if (alg & SSL_kECDH) 
		{
		/* key usage, if present, must allow key agreement */
		if (ku_reject(x, X509v3_KU_KEY_AGREEMENT))
			{
			return 0;
			}
		if (alg & SSL_aECDSA) 
			{
			/* signature alg must be ECDSA */
			if (signature_nid != NID_ecdsa_with_SHA1)
				{
				return 0;
				}
			}
		if (alg & SSL_aRSA)
			{
			/* signature alg must be RSA */
			if ((signature_nid != NID_md5WithRSAEncryption) &&
			    (signature_nid != NID_md4WithRSAEncryption) &&
			    (signature_nid != NID_md2WithRSAEncryption))
				{
				return 0;
				}
			}
		} 
	else if (alg & SSL_aECDSA)
		{
		/* key usage, if present, must allow signing */
		if (ku_reject(x, X509v3_KU_DIGITAL_SIGNATURE))
			{
			return 0;
			}
		}

	return 1;  /* all checks are ok */
	}

/* THIS NEEDS CLEANING UP */
X509 *ssl_get_server_send_cert(SSL *s)
	{
	unsigned long alg,mask,kalg;
	CERT *c;
	int i,is_export;

	c=s->cert;
	ssl_set_cert_masks(c, s->s3->tmp.new_cipher);
	alg=s->s3->tmp.new_cipher->algorithms;
	is_export=SSL_C_IS_EXPORT(s->s3->tmp.new_cipher);
	mask=is_export?c->export_mask:c->mask;
	kalg=alg&(SSL_MKEY_MASK|SSL_AUTH_MASK);

	if (kalg & SSL_kECDH)
		{
		/* we don't need to look at SSL_kECDHE 
		 * since no certificate is needed for
		 * anon ECDH and for authenticated
		 * ECDHE, the check for the auth 
		 * algorithm will set i correctly
		 * NOTE: For ECDH-RSA, we need an ECC
		 * not an RSA cert but for ECDHE-RSA
		 * we need an RSA cert. Placing the
		 * checks for SSL_kECDH before RSA
		 * checks ensures the correct cert is chosen.
		 */
		i=SSL_PKEY_ECC;
		}
	else if (kalg & SSL_aECDSA)
		{
		i=SSL_PKEY_ECC;
		}
	else if (kalg & SSL_kDHr)
		i=SSL_PKEY_DH_RSA;
	else if (kalg & SSL_kDHd)
		i=SSL_PKEY_DH_DSA;
	else if (kalg & SSL_aDSS)
		i=SSL_PKEY_DSA_SIGN;
	else if (kalg & SSL_aRSA)
		{
		if (c->pkeys[SSL_PKEY_RSA_ENC].x509 == NULL)
			i=SSL_PKEY_RSA_SIGN;
		else
			i=SSL_PKEY_RSA_ENC;
		}
	else if (kalg & SSL_aKRB5)
		{
		/* VRS something else here? */
		return(NULL);
		}
	else /* if (kalg & SSL_aNULL) */
		{
		SSLerr(SSL_F_SSL_GET_SERVER_SEND_CERT,ERR_R_INTERNAL_ERROR);
		return(NULL);
		}
	if (c->pkeys[i].x509 == NULL) return(NULL);

	return(c->pkeys[i].x509);
	}

EVP_PKEY *ssl_get_sign_pkey(SSL *s,SSL_CIPHER *cipher)
	{
	unsigned long alg;
	CERT *c;

	alg=cipher->algorithms;
	c=s->cert;

	if ((alg & SSL_aDSS) &&
		(c->pkeys[SSL_PKEY_DSA_SIGN].privatekey != NULL))
		return(c->pkeys[SSL_PKEY_DSA_SIGN].privatekey);
	else if (alg & SSL_aRSA)
		{
		if (c->pkeys[SSL_PKEY_RSA_SIGN].privatekey != NULL)
			return(c->pkeys[SSL_PKEY_RSA_SIGN].privatekey);
		else if (c->pkeys[SSL_PKEY_RSA_ENC].privatekey != NULL)
			return(c->pkeys[SSL_PKEY_RSA_ENC].privatekey);
		else
			return(NULL);
		}
	else if ((alg & SSL_aECDSA) &&
	         (c->pkeys[SSL_PKEY_ECC].privatekey != NULL))
		return(c->pkeys[SSL_PKEY_ECC].privatekey);
	else /* if (alg & SSL_aNULL) */
		{
		SSLerr(SSL_F_SSL_GET_SIGN_PKEY,ERR_R_INTERNAL_ERROR);
		return(NULL);
		}
	}

void ssl_update_cache(SSL *s,int mode)
	{
	int i;

	/* If the session_id_length is 0, we are not supposed to cache it,
	 * and it would be rather hard to do anyway :-) */
	if (s->session->session_id_length == 0) return;

	i=s->ctx->session_cache_mode;
	if ((i & mode) && (!s->hit)
		&& ((i & SSL_SESS_CACHE_NO_INTERNAL_STORE)
		    || SSL_CTX_add_session(s->ctx,s->session))
		&& (s->ctx->new_session_cb != NULL))
		{
		CRYPTO_add(&s->session->references,1,CRYPTO_LOCK_SSL_SESSION);
		if (!s->ctx->new_session_cb(s,s->session))
			SSL_SESSION_free(s->session);
		}

	/* auto flush every 255 connections */
	if ((!(i & SSL_SESS_CACHE_NO_AUTO_CLEAR)) &&
		((i & mode) == mode))
		{
		if (  (((mode & SSL_SESS_CACHE_CLIENT)
			?s->ctx->stats.sess_connect_good
			:s->ctx->stats.sess_accept_good) & 0xff) == 0xff)
			{
			SSL_CTX_flush_sessions(s->ctx,(unsigned long)time(NULL));
			}
		}
	}

SSL_METHOD *SSL_get_ssl_method(SSL *s)
	{
	return(s->method);
	}

int SSL_set_ssl_method(SSL *s,SSL_METHOD *meth)
	{
	int conn= -1;
	int ret=1;

	if (s->method != meth)
		{
		if (s->handshake_func != NULL)
			conn=(s->handshake_func == s->method->ssl_connect);

		if (s->method->version == meth->version)
			s->method=meth;
		else
			{
			s->method->ssl_free(s);
			s->method=meth;
			ret=s->method->ssl_new(s);
			}

		if (conn == 1)
			s->handshake_func=meth->ssl_connect;
		else if (conn == 0)
			s->handshake_func=meth->ssl_accept;
		}
	return(ret);
	}

int SSL_get_error(const SSL *s,int i)
	{
	int reason;
	unsigned long l;
	BIO *bio;

	if (i > 0) return(SSL_ERROR_NONE);

	/* Make things return SSL_ERROR_SYSCALL when doing SSL_do_handshake
	 * etc, where we do encode the error */
	if ((l=ERR_peek_error()) != 0)
		{
		if (ERR_GET_LIB(l) == ERR_LIB_SYS)
			return(SSL_ERROR_SYSCALL);
		else
			return(SSL_ERROR_SSL);
		}

	if ((i < 0) && SSL_want_read(s))
		{
		bio=SSL_get_rbio(s);
		if (BIO_should_read(bio))
			return(SSL_ERROR_WANT_READ);
		else if (BIO_should_write(bio))
			/* This one doesn't make too much sense ... We never try
			 * to write to the rbio, and an application program where
			 * rbio and wbio are separate couldn't even know what it
			 * should wait for.
			 * However if we ever set s->rwstate incorrectly
			 * (so that we have SSL_want_read(s) instead of
			 * SSL_want_write(s)) and rbio and wbio *are* the same,
			 * this test works around that bug; so it might be safer
			 * to keep it. */
			return(SSL_ERROR_WANT_WRITE);
		else if (BIO_should_io_special(bio))
			{
			reason=BIO_get_retry_reason(bio);
			if (reason == BIO_RR_CONNECT)
				return(SSL_ERROR_WANT_CONNECT);
			else if (reason == BIO_RR_ACCEPT)
				return(SSL_ERROR_WANT_ACCEPT);
			else
				return(SSL_ERROR_SYSCALL); /* unknown */
			}
		}

	if ((i < 0) && SSL_want_write(s))
		{
		bio=SSL_get_wbio(s);
		if (BIO_should_write(bio))
			return(SSL_ERROR_WANT_WRITE);
		else if (BIO_should_read(bio))
			/* See above (SSL_want_read(s) with BIO_should_write(bio)) */
			return(SSL_ERROR_WANT_READ);
		else if (BIO_should_io_special(bio))
			{
			reason=BIO_get_retry_reason(bio);
			if (reason == BIO_RR_CONNECT)
				return(SSL_ERROR_WANT_CONNECT);
			else if (reason == BIO_RR_ACCEPT)
				return(SSL_ERROR_WANT_ACCEPT);
			else
				return(SSL_ERROR_SYSCALL);
			}
		}
	if ((i < 0) && SSL_want_x509_lookup(s))
		{
		return(SSL_ERROR_WANT_X509_LOOKUP);
		}

	if (i == 0)
		{
		if (s->version == SSL2_VERSION)
			{
			/* assume it is the socket being closed */
			return(SSL_ERROR_ZERO_RETURN);
			}
		else
			{
			if ((s->shutdown & SSL_RECEIVED_SHUTDOWN) &&
				(s->s3->warn_alert == SSL_AD_CLOSE_NOTIFY))
				return(SSL_ERROR_ZERO_RETURN);
			}
		}
	return(SSL_ERROR_SYSCALL);
	}

int SSL_do_handshake(SSL *s)
	{
	int ret=1;

	if (s->handshake_func == NULL)
		{
		SSLerr(SSL_F_SSL_DO_HANDSHAKE,SSL_R_CONNECTION_TYPE_NOT_SET);
		return(-1);
		}

	s->method->ssl_renegotiate_check(s);

	if (SSL_in_init(s) || SSL_in_before(s))
		{
		ret=s->handshake_func(s);
		}
	return(ret);
	}

/* For the next 2 functions, SSL_clear() sets shutdown and so
 * one of these calls will reset it */
void SSL_set_accept_state(SSL *s)
	{
	s->server=1;
	s->shutdown=0;
	s->state=SSL_ST_ACCEPT|SSL_ST_BEFORE;
	s->handshake_func=s->method->ssl_accept;
	/* clear the current cipher */
	ssl_clear_cipher_ctx(s);
	}

void SSL_set_connect_state(SSL *s)
	{
	s->server=0;
	s->shutdown=0;
	s->state=SSL_ST_CONNECT|SSL_ST_BEFORE;
	s->handshake_func=s->method->ssl_connect;
	/* clear the current cipher */
	ssl_clear_cipher_ctx(s);
	}

int ssl_undefined_function(SSL *s)
	{
	SSLerr(SSL_F_SSL_UNDEFINED_FUNCTION,ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
	return(0);
	}

int ssl_undefined_void_function(void)
	{