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/* 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
/*
* This file implements the Symkey wrapper and the PKCS context
* Interfaces.
*/
#include <stddef.h>
#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 "keyhi.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];
size_t 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 > 120) /* bytes */ {
/* we'd have to generate an RSA key pair > 1024 bits long,
** and that's too costly. Don't even try.
*/
PORT_SetError(SEC_ERROR_CANNOT_MOVE_SENSITIVE_KEY);
goto rsa_failed;
}
rsaParams.keySizeInBits = 1024;
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;
}