--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/nss/lib/pk11wrap/pk11kea.c	Mon Jul 28 10:47:06 2014 +0200
@@ -0,0 +1,131 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+/*
+ * This file implements the Symkey wrapper and the PKCS context
+ * Interfaces.
+ */
+
+#include "seccomon.h"
+#include "secmod.h"
+#include "nssilock.h"
+#include "secmodi.h"
+#include "secmodti.h"
+#include "pkcs11.h"
+#include "pk11func.h"
+#include "secitem.h"
+#include "key.h"
+#include "secasn1.h"
+#include "sechash.h"
+#include "cert.h"
+#include "secerr.h"
+
+/*
+ * find an RSA public key on a card
+ */
+static CK_OBJECT_HANDLE
+pk11_FindRSAPubKey(PK11SlotInfo *slot)
+{
+    CK_KEY_TYPE key_type = CKK_RSA;
+    CK_OBJECT_CLASS class_type = CKO_PUBLIC_KEY;
+    CK_ATTRIBUTE theTemplate[2];
+    int template_count = sizeof(theTemplate)/sizeof(theTemplate[0]);
+    CK_ATTRIBUTE *attrs = theTemplate;
+
+    PK11_SETATTRS(attrs,CKA_CLASS,&class_type,sizeof(class_type)); attrs++;
+    PK11_SETATTRS(attrs,CKA_KEY_TYPE,&key_type,sizeof(key_type)); attrs++;
+    template_count = attrs - theTemplate;
+    PR_ASSERT(template_count <= sizeof(theTemplate)/sizeof(CK_ATTRIBUTE));
+
+    return pk11_FindObjectByTemplate(slot,theTemplate,template_count);
+}
+
+PK11SymKey *
+pk11_KeyExchange(PK11SlotInfo *slot,CK_MECHANISM_TYPE type,
+		 CK_ATTRIBUTE_TYPE operation, CK_FLAGS flags, 
+					PRBool isPerm, PK11SymKey *symKey)
+{
+    PK11SymKey *newSymKey = NULL;
+    SECStatus rv;
+    /* performance improvement can go here --- use a generated key at startup
+     * to generate a per token wrapping key. If it exists, use it, otherwise 
+     * do a full key exchange. */
+
+    /* find a common Key Exchange algorithm */
+    /* RSA */
+    if (PK11_DoesMechanism(symKey->slot, CKM_RSA_PKCS) && 
+				PK11_DoesMechanism(slot,CKM_RSA_PKCS)) {
+	CK_OBJECT_HANDLE pubKeyHandle = CK_INVALID_HANDLE;
+	CK_OBJECT_HANDLE privKeyHandle = CK_INVALID_HANDLE;
+	SECKEYPublicKey *pubKey = NULL;
+	SECKEYPrivateKey *privKey = NULL;
+	SECItem wrapData;
+	unsigned int     symKeyLength = PK11_GetKeyLength(symKey);
+
+	wrapData.data = NULL;
+
+	/* find RSA Public Key on target */
+	pubKeyHandle = pk11_FindRSAPubKey(slot);
+	if (pubKeyHandle != CK_INVALID_HANDLE) {
+	    privKeyHandle = PK11_MatchItem(slot,pubKeyHandle,CKO_PRIVATE_KEY);
+	}
+
+	/* if no key exists, generate a key pair */
+	if (privKeyHandle == CK_INVALID_HANDLE) {
+	    PK11RSAGenParams rsaParams;
+
+	    if (symKeyLength > 53) /* bytes */ {
+		/* we'd have to generate an RSA key pair > 512 bits long,
+		** and that's too costly.  Don't even try. 
+		*/
+		PORT_SetError( SEC_ERROR_CANNOT_MOVE_SENSITIVE_KEY );
+		goto rsa_failed;
+	    }
+	    rsaParams.keySizeInBits = 
+	        (symKeyLength > 21 || symKeyLength == 0) ? 512 : 256;
+	    rsaParams.pe  = 0x10001;
+	    privKey = PK11_GenerateKeyPair(slot,CKM_RSA_PKCS_KEY_PAIR_GEN, 
+			    &rsaParams, &pubKey,PR_FALSE,PR_TRUE,symKey->cx);
+	} else {
+	    /* if keys exist, build SECKEY data structures for them */
+	    privKey = PK11_MakePrivKey(slot,nullKey, PR_TRUE, privKeyHandle,
+					symKey->cx);
+	    if (privKey != NULL) {
+    		pubKey = PK11_ExtractPublicKey(slot, rsaKey, pubKeyHandle);
+		if (pubKey && pubKey->pkcs11Slot) {
+		    PK11_FreeSlot(pubKey->pkcs11Slot);
+		    pubKey->pkcs11Slot = NULL;
+		    pubKey->pkcs11ID = CK_INVALID_HANDLE;
+		}
+	    }
+	}
+	if (privKey == NULL) goto rsa_failed;
+	if (pubKey == NULL)  goto rsa_failed;
+
+        wrapData.len  = SECKEY_PublicKeyStrength(pubKey);
+        if (!wrapData.len) goto rsa_failed;
+        wrapData.data = PORT_Alloc(wrapData.len);
+        if (wrapData.data == NULL) goto rsa_failed;
+
+	/* now wrap the keys in and out */
+	rv = PK11_PubWrapSymKey(CKM_RSA_PKCS, pubKey, symKey, &wrapData);
+	if (rv == SECSuccess) {
+	    newSymKey = PK11_PubUnwrapSymKeyWithFlagsPerm(privKey,
+			&wrapData,type,operation,symKeyLength,flags,isPerm);
+	    /* make sure we wound up where we wanted to be! */
+	    if (newSymKey && newSymKey->slot != slot) {
+		PK11_FreeSymKey(newSymKey);
+		newSymKey = NULL;
+	    }
+	}
+rsa_failed:
+	if (wrapData.data != NULL) PORT_Free(wrapData.data);
+	if (privKey != NULL) SECKEY_DestroyPrivateKey(privKey);
+	if (pubKey != NULL) SECKEY_DestroyPublicKey(pubKey);
+
+	return  newSymKey;
+    }
+    PORT_SetError( SEC_ERROR_NO_MODULE );
+    return NULL;
+}
+