Skip to content
s3_srvr.c 64.1 KiB
Newer Older
				if (SSL_C_IS_EXPORT(c))
					ec=c;
				}
			if (nc != NULL)
				s->s3->tmp.new_cipher=nc;
			else if (ec != NULL)
				s->s3->tmp.new_cipher=ec;
			else
				s->s3->tmp.new_cipher=s->session->cipher;
			}
		else
#endif
		s->s3->tmp.new_cipher=s->session->cipher;
		}
	
	/* we now have the following setup. 
	 * client_random
	 * cipher_list 		- our prefered list of ciphers
	 * ciphers 		- the clients prefered list of ciphers
	 * compression		- basically ignored right now
	 * ssl version is set	- sslv3
	 * s->session		- The ssl session has been setup.
	 * s->hit		- session reuse flag
	 * s->tmp.new_cipher	- the new cipher to use.
	 */

	ret=1;
	if (0)
		{
f_err:
		ssl3_send_alert(s,SSL3_AL_FATAL,al);
		}
err:
	if (ciphers != NULL) sk_SSL_CIPHER_free(ciphers);
Ben Laurie's avatar
Ben Laurie committed
int ssl3_send_server_hello(SSL *s)
	{
	unsigned char *buf;
	unsigned char *p,*d;
	int i,sl;
	unsigned long l,Time;

	if (s->state == SSL3_ST_SW_SRVR_HELLO_A)
		{
		buf=(unsigned char *)s->init_buf->data;
		p=s->s3->server_random;
		Time=time(NULL);			/* Time */
		l2n(Time,p);
		RAND_pseudo_bytes(p,SSL3_RANDOM_SIZE-4);
		/* Do the message type and length last */
		d=p= &(buf[4]);

		*(p++)=s->version>>8;
		*(p++)=s->version&0xff;

		/* Random stuff */
		memcpy(p,s->s3->server_random,SSL3_RANDOM_SIZE);
		p+=SSL3_RANDOM_SIZE;

		/* now in theory we have 3 options to sending back the
		 * session id.  If it is a re-use, we send back the
		 * old session-id, if it is a new session, we send
		 * back the new session-id or we send back a 0 length
		 * session-id if we want it to be single use.
		 * Currently I will not implement the '0' length session-id
		 * 12-Jan-98 - I'll now support the '0' length stuff.
		if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER))
			s->session->session_id_length=0;

		sl=s->session->session_id_length;
		if (sl > (int)sizeof(s->session->session_id))
Bodo Möller's avatar
Bodo Möller committed
			{
			SSLerr(SSL_F_SSL3_SEND_SERVER_HELLO, ERR_R_INTERNAL_ERROR);
			return -1;
			}
		*(p++)=sl;
		memcpy(p,s->session->session_id,sl);
		p+=sl;

		/* put the cipher */
		i=ssl3_put_cipher_by_char(s->s3->tmp.new_cipher,p);
		p+=i;

		/* put the compression method */
		if (s->s3->tmp.new_compression == NULL)
			*(p++)=0;
		else
			*(p++)=s->s3->tmp.new_compression->id;

		/* do the header */
		l=(p-d);
		d=buf;
		*(d++)=SSL3_MT_SERVER_HELLO;
		l2n3(l,d);

		s->state=SSL3_ST_CW_CLNT_HELLO_B;
		/* number of bytes to write */
		s->init_num=p-buf;
		s->init_off=0;
		}

	/* SSL3_ST_CW_CLNT_HELLO_B */
	return(ssl3_do_write(s,SSL3_RT_HANDSHAKE));
	}

Ben Laurie's avatar
Ben Laurie committed
int ssl3_send_server_done(SSL *s)
	{
	unsigned char *p;

	if (s->state == SSL3_ST_SW_SRVR_DONE_A)
		{
		p=(unsigned char *)s->init_buf->data;

		/* do the header */
		*(p++)=SSL3_MT_SERVER_DONE;
		*(p++)=0;
		*(p++)=0;
		*(p++)=0;

		s->state=SSL3_ST_SW_SRVR_DONE_B;
		/* number of bytes to write */
		s->init_num=4;
		s->init_off=0;
		}

	/* SSL3_ST_CW_CLNT_HELLO_B */
	return(ssl3_do_write(s,SSL3_RT_HANDSHAKE));
	}

Ben Laurie's avatar
Ben Laurie committed
int ssl3_send_server_key_exchange(SSL *s)
	unsigned char *q;
	int j,num;
	RSA *rsa;
	unsigned char md_buf[MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH];
	unsigned int u;
Bodo Möller's avatar
Bodo Möller committed
#endif
#ifndef OPENSSL_NO_ECDH
	EC_KEY *ecdh=NULL, *ecdhp;
	unsigned char *encodedPoint = NULL;
	int encodedlen = 0;
	int curve_id = 0;
	BN_CTX *bn_ctx = NULL; 
#endif
	EVP_PKEY *pkey;
	unsigned char *p,*d;
	int al,i;
	unsigned long type;
	int n;
	CERT *cert;
	BIGNUM *r[4];
	int nr[4],kn;
	BUF_MEM *buf;
	EVP_MD_CTX md_ctx;

	EVP_MD_CTX_init(&md_ctx);
	if (s->state == SSL3_ST_SW_KEY_EXCH_A)
		{
		type=s->s3->tmp.new_cipher->algorithms & SSL_MKEY_MASK;

		buf=s->init_buf;

		r[0]=r[1]=r[2]=r[3]=NULL;
		n=0;
		if (type & SSL_kRSA)
			{
			rsa=cert->rsa_tmp;
			if ((rsa == NULL) && (s->cert->rsa_tmp_cb != NULL))
				      SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
				      SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
				if(rsa == NULL)
				{
					al=SSL_AD_HANDSHAKE_FAILURE;
					SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_ERROR_GENERATING_TMP_RSA_KEY);
					goto f_err;
				}
				cert->rsa_tmp=rsa;
				}
			if (rsa == NULL)
				{
				al=SSL_AD_HANDSHAKE_FAILURE;
				SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_RSA_KEY);
				goto f_err;
				}
			r[0]=rsa->n;
			r[1]=rsa->e;
			s->s3->tmp.use_rsa_tmp=1;
			}
		else
#endif
			if (type & SSL_kEDH)
			{
			dhp=cert->dh_tmp;
			if ((dhp == NULL) && (s->cert->dh_tmp_cb != NULL))
				dhp=s->cert->dh_tmp_cb(s,
				      SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
				      SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
				al=SSL_AD_HANDSHAKE_FAILURE;
				SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
				goto f_err;
				}

			if (s->s3->tmp.dh != NULL)
				{
				DH_free(dh);
Bodo Möller's avatar
Bodo Möller committed
				SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
			if ((dh=DHparams_dup(dhp)) == NULL)
				{
				SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
				goto err;
				}

			s->s3->tmp.dh=dh;
Ben Laurie's avatar
Ben Laurie committed
			if ((dhp->pub_key == NULL ||
			     dhp->priv_key == NULL ||
			     (s->options & SSL_OP_SINGLE_DH_USE)))
Ben Laurie's avatar
Ben Laurie committed
				if(!DH_generate_key(dh))
				    {
				    SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,
					   ERR_R_DH_LIB);
				    goto err;
				    }
				}
			else
				{
				dh->pub_key=BN_dup(dhp->pub_key);
				dh->priv_key=BN_dup(dhp->priv_key);
				if ((dh->pub_key == NULL) ||
					(dh->priv_key == NULL))
					{
					SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_DH_LIB);
					goto err;
					}
				}
			r[0]=dh->p;
			r[1]=dh->g;
			r[2]=dh->pub_key;
			}
		else 
#endif
Bodo Möller's avatar
Bodo Möller committed
#ifndef OPENSSL_NO_ECDH
			if (type & SSL_kECDHE)
			{
			ecdhp=cert->ecdh_tmp;
			if ((ecdhp == NULL) && (s->cert->ecdh_tmp_cb != NULL))
				{
				ecdhp=s->cert->ecdh_tmp_cb(s,
				      SSL_C_IS_EXPORT(s->s3->tmp.new_cipher),
				      SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher));
				}
			if (ecdhp == NULL)
				{
				al=SSL_AD_HANDSHAKE_FAILURE;
				SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_MISSING_TMP_ECDH_KEY);
				goto f_err;
				}

			if (s->s3->tmp.ecdh != NULL)
				{
				EC_KEY_free(s->s3->tmp.ecdh); 
				SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);
				goto err;
				}

			/* Duplicate the ECDH structure. */
			if (ecdhp == NULL)
				{
				SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
				goto err;
				}
			if (!EC_KEY_up_ref(ecdhp))
				{
				SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
Bodo Möller's avatar
Bodo Möller committed
				goto err;
				}
			ecdh = ecdhp;

			s->s3->tmp.ecdh=ecdh;
			if ((ecdh->pub_key == NULL) ||
			    (ecdh->priv_key == NULL) ||
			    (s->options & SSL_OP_SINGLE_ECDH_USE))
				{
				if(!EC_KEY_generate_key(ecdh))
				    {
				    SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
				    goto err;
				    }
				}

			if ((ecdh->group == NULL) ||
			    (ecdh->pub_key == NULL) ||
			    (ecdh->priv_key == NULL))
				{
				SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
				goto err;
				}

			if (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher) &&
			    (EC_GROUP_get_degree(ecdh->group) > 163)) 
				{
				SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_ECGROUP_TOO_LARGE_FOR_CIPHER);
				goto err;
				}

			/* XXX: For now, we only support ephemeral ECDH
			 * keys over named (not generic) curves. For 
			 * supported named curves, curve_id is non-zero.
			 */
			if ((curve_id = 
			    nid2curve_id(EC_GROUP_get_nid(ecdh->group)))
			    == 0)
				{
				SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNSUPPORTED_ELLIPTIC_CURVE);
				goto err;
				}

			/* Encode the public key.
			 * First check the size of encoding and
			 * allocate memory accordingly.
			 */
			encodedlen = EC_POINT_point2oct(ecdh->group, 
			    ecdh->pub_key, 
			    POINT_CONVERSION_UNCOMPRESSED, 
			    NULL, 0, NULL);

			encodedPoint = (unsigned char *) 
			    OPENSSL_malloc(encodedlen*sizeof(unsigned char)); 
			bn_ctx = BN_CTX_new();
			if ((encodedPoint == NULL) || (bn_ctx == NULL))
				{
				SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_MALLOC_FAILURE);
				goto err;
				}


			encodedlen = EC_POINT_point2oct(ecdh->group, 
			    ecdh->pub_key, 
			    POINT_CONVERSION_UNCOMPRESSED, 
			    encodedPoint, encodedlen, bn_ctx);

			if (encodedlen == 0) 
				{
				SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_R_ECDH_LIB);
				goto err;
				}

			BN_CTX_free(bn_ctx);  bn_ctx=NULL;

			/* XXX: For now, we only support named (not 
			 * generic) curves in ECDH ephemeral key exchanges.
			 * In this situation, we need three additional bytes
			 * to encode the entire ServerECDHParams
			 * structure. 
			 */
			n = 3 + encodedlen;

			/* We'll generate the serverKeyExchange message
			 * explicitly so we can set these to NULLs
			 */
			r[0]=NULL;
			r[1]=NULL;
			r[2]=NULL;
			}
		else 
#endif /* !OPENSSL_NO_ECDH */
			al=SSL_AD_HANDSHAKE_FAILURE;
			SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE);
			goto f_err;
			}
		for (i=0; r[i] != NULL; i++)
			{
			nr[i]=BN_num_bytes(r[i]);
			n+=2+nr[i];
			}

		if (!(s->s3->tmp.new_cipher->algorithms & SSL_aNULL))
			{
			if ((pkey=ssl_get_sign_pkey(s,s->s3->tmp.new_cipher))
				== NULL)
				{
				al=SSL_AD_DECODE_ERROR;
				goto f_err;
				}
			kn=EVP_PKEY_size(pkey);
			}
		else
			{
			pkey=NULL;
			kn=0;
			}

		if (!BUF_MEM_grow_clean(buf,n+4+kn))
			{
			SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_BUF);
			goto err;
			}
		d=(unsigned char *)s->init_buf->data;
		p= &(d[4]);

		for (i=0; r[i] != NULL; i++)
			{
			s2n(nr[i],p);
			BN_bn2bin(r[i],p);
			p+=nr[i];
			}

Bodo Möller's avatar
Bodo Möller committed
#ifndef OPENSSL_NO_ECDH
		if (type & SSL_kECDHE) 
			{
			/* XXX: For now, we only support named (not generic) curves.
			 * In this situation, the serverKeyExchange message has:
			 * [1 byte CurveType], [1 byte CurveName]
			 * [1 byte length of encoded point], followed by
			 * the actual encoded point itself
			 */
			*p = NAMED_CURVE_TYPE;
			p += 1;
			*p = curve_id;
			p += 1;
			*p = encodedlen;
			p += 1;
			memcpy((unsigned char*)p, 
			    (unsigned char *)encodedPoint, 
			    encodedlen);
			OPENSSL_free(encodedPoint);
			p += encodedlen;
			}
#endif

		/* not anonymous */
		if (pkey != NULL)
			{
			/* n is the length of the params, they start at &(d[4])
			 * and p points to the space at the end. */
			if (pkey->type == EVP_PKEY_RSA)
				{
				q=md_buf;
				j=0;
				for (num=2; num > 0; num--)
					{
Dr. Stephen Henson's avatar
 
Dr. Stephen Henson committed
					EVP_DigestInit_ex(&md_ctx,(num == 2)
						?s->ctx->md5:s->ctx->sha1, NULL);
					EVP_DigestUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
					EVP_DigestUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
					EVP_DigestUpdate(&md_ctx,&(d[4]),n);
Dr. Stephen Henson's avatar
 
Dr. Stephen Henson committed
					EVP_DigestFinal_ex(&md_ctx,q,
Ben Laurie's avatar
Ben Laurie committed
					&(p[2]), &u, pkey->pkey.rsa) <= 0)
					{
					SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_RSA);
					goto err;
					}
Ben Laurie's avatar
Ben Laurie committed
				s2n(u,p);
				n+=u+2;
				if (pkey->type == EVP_PKEY_DSA)
				{
				/* lets do DSS */
Dr. Stephen Henson's avatar
 
Dr. Stephen Henson committed
				EVP_SignInit_ex(&md_ctx,EVP_dss1(), NULL);
				EVP_SignUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
				EVP_SignUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
				EVP_SignUpdate(&md_ctx,&(d[4]),n);
				if (!EVP_SignFinal(&md_ctx,&(p[2]),
					(unsigned int *)&i,pkey))
					{
					SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_DSA);
					goto err;
					}
				s2n(i,p);
				n+=i+2;
				}
			else
Bodo Möller's avatar
Bodo Möller committed
#endif
#if !defined(OPENSSL_NO_ECDSA)
				if (pkey->type == EVP_PKEY_EC)
Bodo Möller's avatar
Bodo Möller committed
				{
				/* let's do ECDSA */
				EVP_SignInit_ex(&md_ctx,EVP_ecdsa(), NULL);
				EVP_SignUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
				EVP_SignUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
				EVP_SignUpdate(&md_ctx,&(d[4]),n);
				if (!EVP_SignFinal(&md_ctx,&(p[2]),
					(unsigned int *)&i,pkey))
					{
					SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,ERR_LIB_ECDSA);
					goto err;
					}
				s2n(i,p);
				n+=i+2;
				}
			else
#endif
				{
				/* Is this error check actually needed? */
				al=SSL_AD_HANDSHAKE_FAILURE;
				SSLerr(SSL_F_SSL3_SEND_SERVER_KEY_EXCHANGE,SSL_R_UNKNOWN_PKEY_TYPE);
				goto f_err;
				}
			}

		*(d++)=SSL3_MT_SERVER_KEY_EXCHANGE;
		l2n3(n,d);

		/* we should now have things packed up, so lets send
		 * it off */
		s->init_num=n+4;
		s->init_off=0;
		}

	s->state = SSL3_ST_SW_KEY_EXCH_B;
	EVP_MD_CTX_cleanup(&md_ctx);
	return(ssl3_do_write(s,SSL3_RT_HANDSHAKE));
f_err:
	ssl3_send_alert(s,SSL3_AL_FATAL,al);
err:
Bodo Möller's avatar
Bodo Möller committed
#ifndef OPENSSL_NO_ECDH
	if (encodedPoint != NULL) OPENSSL_free(encodedPoint);
	BN_CTX_free(bn_ctx);
#endif
	EVP_MD_CTX_cleanup(&md_ctx);
Ben Laurie's avatar
Ben Laurie committed
int ssl3_send_certificate_request(SSL *s)
	{
	unsigned char *p,*d;
	int i,j,nl,off,n;
	STACK_OF(X509_NAME) *sk=NULL;
	X509_NAME *name;
	BUF_MEM *buf;

	if (s->state == SSL3_ST_SW_CERT_REQ_A)
		{
		buf=s->init_buf;

		d=p=(unsigned char *)&(buf->data[4]);

		/* get the list of acceptable cert types */
		p++;
		n=ssl3_get_req_cert_type(s,p);
		d[0]=n;
		p+=n;
		n++;

		off=n;
		p+=2;
		n+=2;

		sk=SSL_get_client_CA_list(s);
		nl=0;
		if (sk != NULL)
			{
			for (i=0; i<sk_X509_NAME_num(sk); i++)
				name=sk_X509_NAME_value(sk,i);
				j=i2d_X509_NAME(name,NULL);
				if (!BUF_MEM_grow_clean(buf,4+n+j+2))
					{
					SSLerr(SSL_F_SSL3_SEND_CERTIFICATE_REQUEST,ERR_R_BUF_LIB);
					goto err;
					}
				p=(unsigned char *)&(buf->data[4+n]);
				if (!(s->options & SSL_OP_NETSCAPE_CA_DN_BUG))
					{
					s2n(j,p);
					i2d_X509_NAME(name,&p);
					n+=2+j;
					nl+=2+j;
					}
				else
					{
					d=p;
					i2d_X509_NAME(name,&p);
					j-=2; s2n(j,d); j+=2;
					n+=j;
					nl+=j;
					}
				}
			}
		/* else no CA names */
		p=(unsigned char *)&(buf->data[4+off]);
		s2n(nl,p);

		d=(unsigned char *)buf->data;
		*(d++)=SSL3_MT_CERTIFICATE_REQUEST;
		l2n3(n,d);

		/* we should now have things packed up, so lets send
		 * it off */

		s->init_num=n+4;
		s->init_off=0;
#ifdef NETSCAPE_HANG_BUG
		p=(unsigned char *)s->init_buf->data + s->init_num;

		/* do the header */
		*(p++)=SSL3_MT_SERVER_DONE;
		*(p++)=0;
		*(p++)=0;
		*(p++)=0;
		s->init_num += 4;
#endif

		}

	/* SSL3_ST_SW_CERT_REQ_B */
	return(ssl3_do_write(s,SSL3_RT_HANDSHAKE));
err:
	return(-1);
	}

static void *KDF1_SHA1(const void *in, size_t inlen, void *out, size_t *outlen)
Ben Laurie's avatar
Ben Laurie committed
int ssl3_get_client_key_exchange(SSL *s)
	{
	int i,al,ok;
	long n;
	unsigned long l;
	unsigned char *p;
	RSA *rsa=NULL;
	EVP_PKEY *pkey=NULL;
Bodo Möller's avatar
Bodo Möller committed
#ifndef OPENSSL_NO_ECDH
	EC_KEY *srvr_ecdh = NULL;
	EVP_PKEY *clnt_pub_pkey = NULL;
	EC_POINT *clnt_ecpoint = NULL;
	BN_CTX *bn_ctx = NULL; 
#endif

Ben Laurie's avatar
Ben Laurie committed
	n=s->method->ssl_get_message(s,
		SSL3_ST_SR_KEY_EXCH_A,
		SSL3_ST_SR_KEY_EXCH_B,
		SSL3_MT_CLIENT_KEY_EXCHANGE,
		&ok);

	if (!ok) return((int)n);
	p=(unsigned char *)s->init_msg;

	l=s->s3->tmp.new_cipher->algorithms;

	if (l & SSL_kRSA)
		{
		/* FIX THIS UP EAY EAY EAY EAY */
		if (s->s3->tmp.use_rsa_tmp)
			{
			if ((s->cert != NULL) && (s->cert->rsa_tmp != NULL))
			/* Don't do a callback because rsa_tmp should
			 * be sent already */
			if (rsa == NULL)
				{
				al=SSL_AD_HANDSHAKE_FAILURE;
				SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_TMP_RSA_PKEY);
				goto f_err;

				}
			}
		else
			{
			pkey=s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey;
			if (	(pkey == NULL) ||
				(pkey->type != EVP_PKEY_RSA) ||
				(pkey->pkey.rsa == NULL))
				{
				al=SSL_AD_HANDSHAKE_FAILURE;
				SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_RSA_CERTIFICATE);
				goto f_err;
				}
			rsa=pkey->pkey.rsa;
			}

		/* TLS */
		if (s->version > SSL3_VERSION)
			{
			n2s(p,i);
			if (n != i+2)
				{
				if (!(s->options & SSL_OP_TLS_D5_BUG))
					{
					SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_TLS_RSA_ENCRYPTED_VALUE_LENGTH_IS_WRONG);
					goto err;
					}
				else
					p-=2;
				}
			else
				n=i;
			}

		i=RSA_private_decrypt((int)n,p,p,rsa,RSA_PKCS1_PADDING);
		if (i != SSL_MAX_MASTER_KEY_LENGTH)
			{
			al=SSL_AD_DECODE_ERROR;
			/* SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_BAD_RSA_DECRYPT); */
		if ((al == -1) && !((p[0] == (s->client_version>>8)) && (p[1] == (s->client_version & 0xff))))
			/* The premaster secret must contain the same version number as the
			 * ClientHello to detect version rollback attacks (strangely, the
			 * protocol does not offer such protection for DH ciphersuites).
			 * However, buggy clients exist that send the negotiated protocol
Bodo Möller's avatar
Bodo Möller committed
			 * version instead if the server does not support the requested
			 * protocol version.
			 * If SSL_OP_TLS_ROLLBACK_BUG is set, tolerate such clients. */
			if (!((s->options & SSL_OP_TLS_ROLLBACK_BUG) &&
				(p[0] == (s->version>>8)) && (p[1] == (s->version & 0xff))))
				{
				al=SSL_AD_DECODE_ERROR;
				/* SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_BAD_PROTOCOL_VERSION_NUMBER); */

				/* The Klima-Pokorny-Rosa extension of Bleichenbacher's attack
				 * (http://eprint.iacr.org/2003/052/) exploits the version
				 * number check as a "bad version oracle" -- an alert would
				 * reveal that the plaintext corresponding to some ciphertext
				 * made up by the adversary is properly formatted except
				 * that the version number is wrong.  To avoid such attacks,
				 * we should treat this just like any other decryption error. */
		if (al != -1)
			{
			/* Some decryption failure -- use random value instead as countermeasure
			 * against Bleichenbacher's attack on PKCS #1 v1.5 RSA padding
			 * (see RFC 2246, section 7.4.7.1). */
			ERR_clear_error();
			i = SSL_MAX_MASTER_KEY_LENGTH;
			p[0] = s->client_version >> 8;
			p[1] = s->client_version & 0xff;
			RAND_pseudo_bytes(p+2, i-2); /* should be RAND_bytes, but we cannot work around a failure */
			}
	
		s->session->master_key_length=
			s->method->ssl3_enc->generate_master_secret(s,
				s->session->master_key,
				p,i);
#endif
		if (l & (SSL_kEDH|SSL_kDHr|SSL_kDHd))
		{
		n2s(p,i);
		if (n != i+2)
			{
			if (!(s->options & SSL_OP_SSLEAY_080_CLIENT_DH_BUG))
				{
				SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_DH_PUBLIC_VALUE_LENGTH_IS_WRONG);
				goto err;
				}
			else
				{
				p-=2;
				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
			{
			if (s->s3->tmp.dh == NULL)
				{
				al=SSL_AD_HANDSHAKE_FAILURE;
				SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_MISSING_TMP_DH_KEY);
				goto f_err;
				}
			else
				dh_srvr=s->s3->tmp.dh;
			}

		pub=BN_bin2bn(p,i,NULL);
		if (pub == NULL)
			{
			SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,SSL_R_BN_LIB);
			goto err;
			}
		i=DH_compute_key(p,pub,dh_srvr);

		if (i <= 0)
			{
			SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,ERR_R_DH_LIB);
			goto err;
			}

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

		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);
                krb5_error_code		krb5rc;
		krb5_data		enc_ticket;
		krb5_data		authenticator;
		krb5_data		enc_pms;
                KSSL_CTX		*kssl_ctx = s->kssl_ctx;
		EVP_CIPHER_CTX		ciph_ctx;
		EVP_CIPHER		*enc = NULL;
		unsigned char		iv[EVP_MAX_IV_LENGTH];
		unsigned char		pms[SSL_MAX_MASTER_KEY_LENGTH
                                               + EVP_MAX_BLOCK_LENGTH];
		int                     padl, outl;
		krb5_timestamp		authtime = 0;
		krb5_ticket_times	ttimes;
Dr. Stephen Henson's avatar
 
Dr. Stephen Henson committed
		EVP_CIPHER_CTX_init(&ciph_ctx);

                if (!kssl_ctx)  kssl_ctx = kssl_ctx_new();
Dr. Stephen Henson's avatar
 
Dr. Stephen Henson committed
		enc_ticket.data = (char *)p;
		p+=enc_ticket.length;

		n2s(p,i);
		authenticator.length = i;
Dr. Stephen Henson's avatar
 
Dr. Stephen Henson committed
		authenticator.data = (char *)p;
		p+=authenticator.length;

		n2s(p,i);
		enc_pms.length = i;
Dr. Stephen Henson's avatar
 
Dr. Stephen Henson committed
		enc_pms.data = (char *)p;
		/* Note that the length is checked again below,
		** after decryption
		*/
Lutz Jänicke's avatar
Lutz Jänicke committed
		if(enc_pms.length > sizeof pms)
			{
			SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
			       SSL_R_DATA_LENGTH_TOO_LONG);
			goto err;
			}

		if (n != (long)(enc_ticket.length + authenticator.length +
						enc_pms.length + 6))
			{
			SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
				SSL_R_DATA_LENGTH_TOO_LONG);
			goto err;
			}

                if ((krb5rc = kssl_sget_tkt(kssl_ctx, &enc_ticket, &ttimes,
					&kssl_err)) != 0)
                        {
#ifdef KSSL_DEBUG
                        printf("kssl_sget_tkt rtn %d [%d]\n",
                                krb5rc, kssl_err.reason);
                        if (kssl_err.text)
                                printf("kssl_err text= %s\n", kssl_err.text);
#endif	/* KSSL_DEBUG */
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
		/*  Note: no authenticator is not considered an error,
		**  but will return authtime == 0.
		*/
		if ((krb5rc = kssl_check_authent(kssl_ctx, &authenticator,
					&authtime, &kssl_err)) != 0)
			{
#ifdef KSSL_DEBUG
                        printf("kssl_check_authent rtn %d [%d]\n",
                                krb5rc, kssl_err.reason);
                        if (kssl_err.text)
                                printf("kssl_err text= %s\n", kssl_err.text);
#endif	/* KSSL_DEBUG */
                        SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
                                kssl_err.reason);
                        goto err;
			}

		if ((krb5rc = kssl_validate_times(authtime, &ttimes)) != 0)
			{
			SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE, krb5rc);
#ifdef KSSL_DEBUG
                kssl_ctx_show(kssl_ctx);
#endif	/* KSSL_DEBUG */

		enc = kssl_map_enc(kssl_ctx->enctype);
		memset(iv, 0, sizeof iv);	/* per RFC 1510 */
Richard Levitte's avatar
Richard Levitte committed
		if (!EVP_DecryptInit_ex(&ciph_ctx,enc,NULL,kssl_ctx->key,iv))
			{
			SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
				SSL_R_DECRYPTION_FAILED);
			goto err;
			}
		if (!EVP_DecryptUpdate(&ciph_ctx, pms,&outl,
Dr. Stephen Henson's avatar
 
Dr. Stephen Henson committed
					(unsigned char *)enc_pms.data, enc_pms.length))
			{
			SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
				SSL_R_DECRYPTION_FAILED);
			goto err;
			}
		if (outl > SSL_MAX_MASTER_KEY_LENGTH)
			{
			SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
				SSL_R_DATA_LENGTH_TOO_LONG);
			goto err;
			}
		if (!EVP_DecryptFinal_ex(&ciph_ctx,&(pms[outl]),&padl))
			{
			SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
				SSL_R_DECRYPTION_FAILED);
			goto err;
			}
		outl += padl;
		if (outl > SSL_MAX_MASTER_KEY_LENGTH)
			{
			SSLerr(SSL_F_SSL3_GET_CLIENT_KEY_EXCHANGE,
				SSL_R_DATA_LENGTH_TOO_LONG);
			goto err;
			}
		EVP_CIPHER_CTX_cleanup(&ciph_ctx);

                s->session->master_key_length=
                        s->method->ssl3_enc->generate_master_secret(s,