Commit d61be855 authored by Dr. Stephen Henson's avatar Dr. Stephen Henson
Browse files

Return an error if no recipient type matches. 

If the key type does not match any CMS recipient type return
an error instead of using a random key (MMA mitigation). This
does not leak any useful information to an attacker.

PR#3348
parent 9e456a85

crypto/cms/cms_smime.c

+3 −2
Original line number Diff line number Diff line
@@ -611,7 +611,7 @@ int CMS_decrypt_set1_pkey(CMS_ContentInfo *cms, EVP_PKEY *pk, X509 *cert) 
	STACK_OF(CMS_RecipientInfo) *ris;

	CMS_RecipientInfo *ri;

	int i, r;

	int debug = 0;

	int debug = 0, ri_match = 0;

	ris = CMS_get0_RecipientInfos(cms);

	if (ris)

		debug = cms->d.envelopedData->encryptedContentInfo->debug;
@@ -620,6 +620,7 @@ int CMS_decrypt_set1_pkey(CMS_ContentInfo *cms, EVP_PKEY *pk, X509 *cert) 
		ri = sk_CMS_RecipientInfo_value(ris, i);

		if (CMS_RecipientInfo_type(ri) != CMS_RECIPINFO_TRANS)

				continue;

		ri_match = 1;

		/* If we have a cert try matching RecipientInfo

		 * otherwise try them all.

		 */
@@ -655,7 +656,7 @@ int CMS_decrypt_set1_pkey(CMS_ContentInfo *cms, EVP_PKEY *pk, X509 *cert) 
			}

		}

	/* If no cert and not debugging always return success */

	if (!cert && !debug)

	if (ri_match && !cert && !debug)

		{

		ERR_clear_error();

		return 1;