Allow PKCS7_decrypt() to work if no cert supplied.

CHANGES

@@ -14,7 +14,10 @@
 
  Changes between 0.9.8 and 0.9.8a  [XX xxx XXXX]
 
-  *) 
+  *) Make PKCS7_decrypt() work even if no certificate is supplied by
+     attempting to decrypt each encrypted key in turn. Add support to
+     smime utility.
+     [Steve Henson]
 
  Changes between 0.9.7h and 0.9.8  [05 Jul 2005]
 

apps/smime.c

@@ -384,9 +384,9 @@ int MAIN(int argc, char **argv)
 		}
 	else if (operation == SMIME_DECRYPT)
 		{
-		if (!recipfile)
+		if (!recipfile && !keyfile)
 			{
-			BIO_printf(bio_err, "No recipient certificate and key specified\n");
+			BIO_printf(bio_err, "No recipient certificate or key specified\n");
 			badarg = 1;
 			}
 		}

crypto/pkcs7/pk7_doit.c

@@ -62,6 +62,7 @@
 #include <openssl/objects.h>
 #include <openssl/x509.h>
 #include <openssl/x509v3.h>
+#include <openssl/err.h>
 
 static int add_attribute(STACK_OF(X509_ATTRIBUTE) **sk, int nid, int atrtype,
 			 void *value);
@@ -307,6 +308,17 @@ err:
 	return(out);
 	}
 
+static int pkcs7_cmp_ri(PKCS7_RECIP_INFO *ri, X509 *pcert)
+	{
+	int ret;
+	ret = X509_NAME_cmp(ri->issuer_and_serial->issuer,
+				pcert->cert_info->issuer);
+	if (ret)
+		return ret;
+	return M_ASN1_INTEGER_cmp(pcert->cert_info->serialNumber,
+					ri->issuer_and_serial->serial);
+	}
+
 /* int */
 BIO *PKCS7_dataDecode(PKCS7 *p7, EVP_PKEY *pkey, BIO *in_bio, X509 *pcert)
 	{
@@ -417,18 +429,18 @@ BIO *PKCS7_dataDecode(PKCS7 *p7, EVP_PKEY *pkey, BIO *in_bio, X509 *pcert)
 		 * (if any)
 		 */
 
-		for (i=0; i<sk_PKCS7_RECIP_INFO_num(rsk); i++) {
-			ri=sk_PKCS7_RECIP_INFO_value(rsk,i);
-			if(!X509_NAME_cmp(ri->issuer_and_serial->issuer,
-					pcert->cert_info->issuer) &&
-			     !M_ASN1_INTEGER_cmp(pcert->cert_info->serialNumber,
-					ri->issuer_and_serial->serial)) break;
-			ri=NULL;
-		}
-		if (ri == NULL) {
-			PKCS7err(PKCS7_F_PKCS7_DATADECODE,
-				 PKCS7_R_NO_RECIPIENT_MATCHES_CERTIFICATE);
-			goto err;
+		if (pcert) {
+			for (i=0; i<sk_PKCS7_RECIP_INFO_num(rsk); i++) {
+				ri=sk_PKCS7_RECIP_INFO_value(rsk,i);
+				if (!pkcs7_cmp_ri(ri, pcert))
+					break;
+				ri=NULL;
+			}
+			if (ri == NULL) {
+				PKCS7err(PKCS7_F_PKCS7_DATADECODE,
+				      PKCS7_R_NO_RECIPIENT_MATCHES_CERTIFICATE);
+				goto err;
+			}
 		}
 
 		jj=EVP_PKEY_size(pkey);
@@ -439,12 +451,40 @@ BIO *PKCS7_dataDecode(PKCS7 *p7, EVP_PKEY *pkey, BIO *in_bio, X509 *pcert)
 			goto err;
 			}
 
-		jj=EVP_PKEY_decrypt(tmp, M_ASN1_STRING_data(ri->enc_key),
-			M_ASN1_STRING_length(ri->enc_key), pkey);
-		if (jj <= 0)
+		/* If we haven't got a certificate try each ri in turn */
+
+		if (pcert == NULL)
 			{
-			PKCS7err(PKCS7_F_PKCS7_DATADECODE,ERR_R_EVP_LIB);
-			goto err;
+			for (i=0; i<sk_PKCS7_RECIP_INFO_num(rsk); i++)
+				{
+				ri=sk_PKCS7_RECIP_INFO_value(rsk,i);
+				jj=EVP_PKEY_decrypt(tmp,
+					M_ASN1_STRING_data(ri->enc_key),
+					M_ASN1_STRING_length(ri->enc_key),
+						pkey);
+				if (jj > 0)
+					break;
+				ERR_clear_error();
+				ri = NULL;
+				}
+			if (ri == NULL)
+				{
+				PKCS7err(PKCS7_F_PKCS7_DATADECODE,
+				      PKCS7_R_NO_RECIPIENT_MATCHES_KEY);
+				goto err;
+				}
+			}
+		else
+			{
+			jj=EVP_PKEY_decrypt(tmp,
+				M_ASN1_STRING_data(ri->enc_key),
+				M_ASN1_STRING_length(ri->enc_key), pkey);
+			if (jj <= 0)
+				{
+				PKCS7err(PKCS7_F_PKCS7_DATADECODE,
+								ERR_R_EVP_LIB);
+				goto err;
+				}
 			}
 
 		evp_ctx=NULL;

crypto/pkcs7/pk7_smime.c

@@ -441,7 +441,7 @@ int PKCS7_decrypt(PKCS7 *p7, EVP_PKEY *pkey, X509 *cert, BIO *data, int flags)
 		return 0;
 	}
 
-	if(!X509_check_private_key(cert, pkey)) {
+	if(cert && !X509_check_private_key(cert, pkey)) {
 		PKCS7err(PKCS7_F_PKCS7_DECRYPT,
 				PKCS7_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
 		return 0;

crypto/pkcs7/pkcs7.h

@@ -432,6 +432,7 @@ void ERR_load_PKCS7_strings(void);
 #define PKCS7_R_NO_MULTIPART_BODY_FAILURE		 136
 #define PKCS7_R_NO_MULTIPART_BOUNDARY			 137
 #define PKCS7_R_NO_RECIPIENT_MATCHES_CERTIFICATE	 115
+#define PKCS7_R_NO_RECIPIENT_MATCHES_KEY		 146
 #define PKCS7_R_NO_SIGNATURES_ON_DATA			 123
 #define PKCS7_R_NO_SIGNERS				 142
 #define PKCS7_R_NO_SIG_CONTENT_TYPE			 138

crypto/pkcs7/pkcs7err.c

@@ -124,6 +124,7 @@ static ERR_STRING_DATA PKCS7_str_reasons[]=
 {ERR_REASON(PKCS7_R_NO_MULTIPART_BODY_FAILURE),"no multipart body failure"},
 {ERR_REASON(PKCS7_R_NO_MULTIPART_BOUNDARY),"no multipart boundary"},
 {ERR_REASON(PKCS7_R_NO_RECIPIENT_MATCHES_CERTIFICATE),"no recipient matches certificate"},
+{ERR_REASON(PKCS7_R_NO_RECIPIENT_MATCHES_KEY),"no recipient matches key"},
 {ERR_REASON(PKCS7_R_NO_SIGNATURES_ON_DATA),"no signatures on data"},
 {ERR_REASON(PKCS7_R_NO_SIGNERS)          ,"no signers"},
 {ERR_REASON(PKCS7_R_NO_SIG_CONTENT_TYPE) ,"no sig content type"},