Commit 66e8211c authored by Dr. Stephen Henson's avatar Dr. Stephen Henson
Browse files

Don't try and verify signatures if key is NULL (CVE-2013-0166) 

Add additional check to catch this in ASN1_item_verify too.
parent dd2dee60

CHANGES

+4 −0
Original line number Diff line number Diff line
@@ -4,6 +4,10 @@ 


 Changes between 0.9.8x and 0.9.8y [xx XXX xxxx]



  *) Return an error when checking OCSP signatures when key is NULL.

     This fixes a DoS attack. (CVE-2013-0166)

     [Steve Henson]



  *) Call OCSP Stapling callback after ciphersuite has been chosen, so

     the right response is stapled. Also change SSL_get_certificate()

     so it returns the certificate actually sent.

crypto/asn1/a_verify.c

+6 −0
Original line number Diff line number Diff line
@@ -138,6 +138,12 @@ int ASN1_item_verify(const ASN1_ITEM *it, X509_ALGOR *a, ASN1_BIT_STRING *signat 
	unsigned char *buf_in=NULL;

	int ret= -1,i,inl;



	if (!pkey)

		{

		ASN1err(ASN1_F_ASN1_ITEM_VERIFY, ERR_R_PASSED_NULL_PARAMETER);

		return -1;

		}



	EVP_MD_CTX_init(&ctx);

	i=OBJ_obj2nid(a->algorithm);

	type=EVP_get_digestbyname(OBJ_nid2sn(i));

crypto/ocsp/ocsp_vfy.c

+6 −3
Original line number Diff line number Diff line
@@ -91,9 +91,12 @@ int OCSP_basic_verify(OCSP_BASICRESP *bs, STACK_OF(X509) *certs, 
		{

		EVP_PKEY *skey;

		skey = X509_get_pubkey(signer);

		if (skey)

			{

			ret = OCSP_BASICRESP_verify(bs, skey, 0);

			EVP_PKEY_free(skey);

		if(ret <= 0)

			}

		if(!skey || ret <= 0)

			{

			OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, OCSP_R_SIGNATURE_FAILURE);

			goto end;