add support for use of fixed DH client certificates (0d609395) · Commits · CYBER - Cyber Security / TS 103 523 MSP / TLMSP / TLMSP OpenSSL

CHANGES

+4 −0

Original line number	Diff line number	Diff line
		@@ -4,6 +4,10 @@

		Changes between 1.0.1 and 1.1.0 [xx XXX xxxx]

		*) Support for fixed DH ciphersuite client authentication: where both
		server and client use DH certificates with common parameters.
		[Steve Henson]

		*) Support for fixed DH ciphersuites: those requiring DH server
		certificates.
		[Steve Henson]

ssl/s3_clnt.c

+73 −19

Original line number	Diff line number	Diff line
		@@ -2428,7 +2428,21 @@ int ssl3_send_client_key_exchange(SSL *s)
		goto err;
		}
		}

		if (s->s3->flags & TLS1_FLAGS_SKIP_CERT_VERIFY)
		{
		/* Use client certificate key */
		EVP_PKEY *clkey = s->cert->key->privatekey;
		if (clkey)
		dh_clnt = EVP_PKEY_get1_DH(clkey);
		if (dh_clnt == NULL)
		{
		SSLerr(SSL_F_SSL3_SEND_CLIENT_KEY_EXCHANGE,
		ERR_R_INTERNAL_ERROR);
		goto err;
		}
		}
		else
		{
		/* generate a new random key */
		if ((dh_clnt=DHparams_dup(dh_srvr)) == NULL)
		{
		@@ -2441,6 +2455,7 @@ int ssl3_send_client_key_exchange(SSL *s)
		DH_free(dh_clnt);
		goto err;
		}
		}

		/* use the 'p' output buffer for the DH key, but
		* make sure to clear it out afterwards */
		@@ -2463,11 +2478,16 @@ int ssl3_send_client_key_exchange(SSL *s)
		/* clean up */
		memset(p,0,n);

		if (s->s3->flags & TLS1_FLAGS_SKIP_CERT_VERIFY)
		n = 0;
		else
		{
		/* send off the data */
		n=BN_num_bytes(dh_clnt->pub_key);
		s2n(n,p);
		BN_bn2bin(dh_clnt->pub_key,p);
		n+=2;
		}

		DH_free(dh_clnt);

		@@ -3054,6 +3074,40 @@ err:
		return(-1);
		}

		/* Check a certificate can be used for client authentication. Currently
		* just check cert exists and if static DH client certificates can be used.
		*/
		static int ssl3_check_client_certificate(SSL *s)
		{
		unsigned long alg_k;
		if (!s->cert \|\| !s->cert->key->x509 \|\| !s->cert->key->privatekey)
		return 0;
		alg_k=s->s3->tmp.new_cipher->algorithm_mkey;
		/* See if we can use client certificate for fixed DH */
		if (alg_k & (SSL_kDHr\|SSL_kDHd))
		{
		SESS_CERT *scert = s->session->sess_cert;
		int i = scert->peer_cert_type;
		EVP_PKEY clkey = NULL, spkey = NULL;
		clkey = s->cert->key->privatekey;
		/* If client key not DH assume it can be used */
		if (EVP_PKEY_id(clkey) != EVP_PKEY_DH)
		return 1;
		if (i >= 0)
		spkey = X509_get_pubkey(scert->peer_pkeys[i].x509);
		if (spkey)
		{
		/* Compare server and client parameters */
		i = EVP_PKEY_cmp_parameters(clkey, spkey);
		EVP_PKEY_free(spkey);
		if (i != 1)
		return 0;
		}
		s->s3->flags \|= TLS1_FLAGS_SKIP_CERT_VERIFY;
		}
		return 1;
		}

		int ssl3_send_client_certificate(SSL *s)
		{
		X509 *x509=NULL;
		@@ -3063,12 +3117,10 @@ int ssl3_send_client_certificate(SSL *s)

		if (s->state == SSL3_ST_CW_CERT_A)
		{
		if ((s->cert == NULL) \|\|
		(s->cert->key->x509 == NULL) \|\|
		(s->cert->key->privatekey == NULL))
		s->state=SSL3_ST_CW_CERT_B;
		else
		if (ssl3_check_client_certificate(s))
		s->state=SSL3_ST_CW_CERT_C;
		else
		s->state=SSL3_ST_CW_CERT_B;
		}

		/* We need to get a client cert */
		@@ -3100,6 +3152,8 @@ int ssl3_send_client_certificate(SSL *s)

		if (x509 != NULL) X509_free(x509);
		if (pkey != NULL) EVP_PKEY_free(pkey);
		if (i && !ssl3_check_client_certificate(s))
		i = 0;
		if (i == 0)
		{
		if (s->version == SSL3_VERSION)

ssl/s3_srvr.c

+46 −30

Original line number	Diff line number	Diff line
		@@ -298,6 +298,7 @@ int ssl3_accept(SSL *s)

		s->init_num=0;
		s->s3->flags &= ~SSL3_FLAGS_SGC_RESTART_DONE;
		s->s3->flags &= ~TLS1_FLAGS_SKIP_CERT_VERIFY;

		if (s->state != SSL_ST_RENEGOTIATE)
		{
		@@ -2132,7 +2133,7 @@ int ssl3_get_client_key_exchange(SSL *s)
		#endif
		#ifndef OPENSSL_NO_DH
		BIGNUM *pub=NULL;
		DH *dh_srvr;
		DH dh_srvr, dh_clnt = NULL;
		#endif
		#ifndef OPENSSL_NO_KRB5
		KSSL_ERR kssl_err;
		@@ -2266,8 +2267,11 @@ int ssl3_get_client_key_exchange(SSL *s)
		#ifndef OPENSSL_NO_DH
		if (alg_k & (SSL_kEDH\|SSL_kDHr\|SSL_kDHd))
		{
		int idx = -1;
		EVP_PKEY *skey = NULL;
		if (n)
		n2s(p,i);
		if (n != i+2)
		if (n && n != i+2)
		{
		if (!(s->options & SSL_OP_SSLEAY_080_CLIENT_DH_BUG))
		{
		@@ -2280,23 +2284,13 @@ int ssl3_get_client_key_exchange(SSL *s)
		i=(int)n;
		}
		}

		if (n == 0L) /* the parameters are in the cert */
		{
		al=SSL_AD_HANDSHAKE_FAILURE;
		SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_UNABLE_TO_DECODE_DH_CERTS);
		goto f_err;
		}
		else
		{
		int idx = -1;
		if (alg_k & SSL_kDHr)
		idx = SSL_PKEY_DH_RSA;
		else if (alg_k & SSL_kDHd)
		idx = SSL_PKEY_DH_DSA;
		if (idx >= 0)
		{
		EVP_PKEY *skey = s->cert->pkeys[idx].privatekey;
		skey = s->cert->pkeys[idx].privatekey;
		if ((skey == NULL) \|\|
		(skey->type != EVP_PKEY_DH) \|\|
		(skey->pkey.dh == NULL))
		@@ -2315,8 +2309,26 @@ int ssl3_get_client_key_exchange(SSL *s)
		}
		else
		dh_srvr=s->s3->tmp.dh;
		}

		if (n == 0L)
		{
		/* Get pubkey from cert */
		EVP_PKEY *clkey=X509_get_pubkey(s->session->peer);
		if (clkey)
		{
		if (EVP_PKEY_cmp_parameters(clkey, skey) == 1)
		dh_clnt = EVP_PKEY_get1_DH(clkey);
		}
		if (dh_clnt == NULL)
		{
		al=SSL_AD_HANDSHAKE_FAILURE;
		SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
		goto f_err;
		}
		EVP_PKEY_free(clkey);
		pub = dh_clnt->pub_key;
		}
		else
		pub=BN_bin2bn(p,i,NULL);
		if (pub == NULL)
		{
		@@ -2335,13 +2347,17 @@ int ssl3_get_client_key_exchange(SSL *s)

		DH_free(s->s3->tmp.dh);
		s->s3->tmp.dh=NULL;

		if (dh_clnt)
		DH_free(dh_clnt);
		else
		BN_clear_free(pub);
		pub=NULL;
		s->session->master_key_length=
		s->method->ssl3_enc->generate_master_secret(s,
		s->session->master_key,p,i);
		OPENSSL_cleanse(p,i);
		if (dh_clnt)
		return 2;
		}
		else
		#endif