Implemented hasher_t using PKCS#11

2010-08-04 09:26:22 +02:00
parent 66267ea515
commit 0f0fc891d8
4 changed files with 336 additions and 0 deletions
@@ -0,0 +1,268 @@
+/*
+ * Copyright (C) 2010 Martin Willi
+ * Copyright (C) 2010 revosec AG
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+#include "pkcs11_hasher.h"
+
+#include <unistd.h>
+
+#include <debug.h>
+
+#include "pkcs11_manager.h"
+
+typedef struct private_pkcs11_hasher_t private_pkcs11_hasher_t;
+
+/**
+ * Private data of an pkcs11_hasher_t object.
+ */
+struct private_pkcs11_hasher_t {
+
+	/**
+	 * Public pkcs11_hasher_t interface.
+	 */
+	pkcs11_hasher_t public;
+
+	/**
+	 * PKCS#11 library
+	 */
+	pkcs11_library_t *lib;
+
+	/**
+	 * Mechanism for this hasher
+	 */
+	CK_MECHANISM_PTR mech;
+
+	/**
+	 * Token session
+	 */
+	CK_SESSION_HANDLE session;
+
+	/**
+	 * size of the hash
+	 */
+	size_t size;
+};
+
+METHOD(hasher_t, get_hash_size, size_t,
+	private_pkcs11_hasher_t *this)
+{
+	return this->size;
+}
+
+/**
+ * Try to handle errors
+ */
+static void handle_error(private_pkcs11_hasher_t *this, CK_RV rv)
+{
+	switch (rv)
+	{
+		case CKR_SESSION_CLOSED:
+		case CKR_SESSION_HANDLE_INVALID:
+		case CKR_USER_NOT_LOGGED_IN:
+		case CKR_PIN_EXPIRED:
+		case CKR_OPERATION_NOT_INITIALIZED:
+			/* reopen session if we are in DigestInit? */
+		case CKR_CRYPTOKI_NOT_INITIALIZED:
+		case CKR_ARGUMENTS_BAD:
+		case CKR_DEVICE_ERROR:
+		case CKR_DEVICE_REMOVED:
+		case CKR_GENERAL_ERROR:
+		case CKR_MECHANISM_INVALID:
+		case CKR_MECHANISM_PARAM_INVALID:
+			DBG1(DBG_CFG, "PKCS#11 hasher fatal error: %N", ck_rv_names, rv);
+			abort();
+			break;
+		case CKR_FUNCTION_CANCELED:
+		case CKR_FUNCTION_FAILED:
+		case CKR_OPERATION_ACTIVE:
+		case CKR_HOST_MEMORY:
+		case CKR_DEVICE_MEMORY:
+			DBG1(DBG_CFG, "PKCS#11 hasher critical error: %N", ck_rv_names, rv);
+			sleep(1);
+			break;
+	}
+}
+
+METHOD(hasher_t, reset, void,
+	private_pkcs11_hasher_t *this)
+{
+	CK_RV rv;
+
+	while ((rv = this->lib->f->C_DigestInit(this->session,
+								this->mech)) != CKR_OK)
+	{
+		handle_error(this, rv);
+	}
+}
+
+METHOD(hasher_t, get_hash, void,
+	private_pkcs11_hasher_t *this, chunk_t chunk, u_int8_t *hash)
+{
+	CK_RV rv;
+	CK_ULONG len;
+
+	if (chunk.len)
+	{
+		while ((rv = this->lib->f->C_DigestUpdate(this->session,
+									chunk.ptr, chunk.len)) != CKR_OK)
+		{
+			handle_error(this, rv);
+		}
+	}
+	if (hash)
+	{
+		len = this->size;
+		while ((rv = this->lib->f->C_DigestFinal(this->session,
+								hash, &len)) != CKR_OK)
+		{
+			handle_error(this, rv);
+		}
+		reset(this);
+	}
+}
+
+METHOD(hasher_t, allocate_hash, void,
+	private_pkcs11_hasher_t *this, chunk_t chunk, chunk_t *hash)
+{
+	if (hash)
+	{
+		*hash = chunk_alloc(this->size);
+		get_hash(this, chunk, hash->ptr);
+	}
+	else
+	{
+		get_hash(this, chunk, NULL);
+	}
+}
+
+METHOD(hasher_t, destroy, void,
+	private_pkcs11_hasher_t *this)
+{
+	this->lib->f->C_CloseSession(this->session);
+	free(this);
+}
+
+/**
+ * Get the Cryptoki mechanism for a hash algorithm
+ */
+static CK_MECHANISM_PTR algo_to_mechanism(hash_algorithm_t algo, size_t *size)
+{
+	static struct {
+		hash_algorithm_t algo;
+		CK_MECHANISM mechanism;
+		size_t size;
+	} mappings[] = {
+		{HASH_MD2,		{CKM_MD2,		NULL, 0},	HASH_SIZE_MD2},
+		{HASH_MD5,		{CKM_MD5,		NULL, 0},	HASH_SIZE_MD5},
+		{HASH_SHA1,		{CKM_SHA_1,		NULL, 0},	HASH_SIZE_SHA1},
+		{HASH_SHA256,	{CKM_SHA256,	NULL, 0},	HASH_SIZE_SHA256},
+		{HASH_SHA384,	{CKM_SHA384,	NULL, 0},	HASH_SIZE_SHA384},
+		{HASH_SHA512,	{CKM_SHA512,	NULL, 0},	HASH_SIZE_SHA512},
+	};
+	int i;
+
+	for (i = 0; i < countof(mappings); i++)
+	{
+		if (mappings[i].algo == algo)
+		{
+			*size = mappings[i].size;
+			return &mappings[i].mechanism;
+		}
+	}
+	return NULL;
+}
+
+/**
+ * Find a token we can use for a hash algorithm
+ */
+static pkcs11_library_t* find_token(hash_algorithm_t algo,
+			CK_SESSION_HANDLE *session, CK_MECHANISM_PTR *mout, size_t *size)
+{
+	enumerator_t *tokens, *mechs;
+	pkcs11_manager_t *manager;
+	pkcs11_library_t *current, *found = NULL;
+	CK_MECHANISM_TYPE type;
+	CK_MECHANISM_PTR mech;
+	CK_SLOT_ID slot;
+
+	mech = algo_to_mechanism(algo, size);
+	if (!mech)
+	{
+		return NULL;
+	}
+	manager = pkcs11_manager_get();
+	if (!manager)
+	{
+		return NULL;
+	}
+	tokens = manager->create_token_enumerator(manager);
+	while (tokens->enumerate(tokens, &current, &slot))
+	{
+		mechs = current->create_mechanism_enumerator(current, slot);
+		while (mechs->enumerate(mechs, &type, NULL))
+		{
+			if (type == mech->mechanism)
+			{
+				if (current->f->C_OpenSession(slot, CKF_SERIAL_SESSION,
+											  NULL, NULL, session) == CKR_OK)
+				{
+					found = current;
+					*mout = mech;
+					break;
+				}
+			}
+		}
+		mechs->destroy(mechs);
+		if (found)
+		{
+			break;
+		}
+	}
+	tokens->destroy(tokens);
+	return found;
+}
+
+/**
+ * See header
+ */
+pkcs11_hasher_t *pkcs11_hasher_create(hash_algorithm_t algo)
+{
+	private_pkcs11_hasher_t *this;
+	CK_RV rv;
+
+	INIT(this,
+		.public.hasher = {
+			.get_hash_size = _get_hash_size,
+			.reset = _reset,
+			.get_hash = _get_hash,
+			.allocate_hash = _allocate_hash,
+			.destroy = _destroy,
+		},
+	);
+
+	this->lib = find_token(algo, &this->session, &this->mech, &this->size);
+	if (!this->lib)
+	{
+		free(this);
+		return NULL;
+	}
+	rv = this->lib->f->C_DigestInit(this->session, this->mech);
+	if (rv != CKR_OK)
+	{
+		DBG1(DBG_CFG, "C_DigestInit() failed: %N", ck_rv_names, rv);
+		destroy(this);
+		return NULL;
+	}
+	return &this->public;
+}