1/*
2 * Copyright (c) 2000-2001,2011-2012,2014 Apple Inc. All Rights Reserved.
3 *
4 * The contents of this file constitute Original Code as defined in and are
5 * subject to the Apple Public Source License Version 1.2 (the 'License').
6 * You may not use this file except in compliance with the License. Please obtain
7 * a copy of the License at http://www.apple.com/publicsource and read it before
8 * using this file.
9 *
10 * This Original Code and all software distributed under the License are
11 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS
12 * OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT
13 * LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
14 * PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the
15 * specific language governing rights and limitations under the License.
16 */
17
18
19/*
20 * rc5Context.cpp - glue between BlockCrytpor and ssleay RC5 implementation
21 */
22
23#include <openssl/rc5.h>
24#include <misc/rc5_locl.h>
25#include "rc5Context.h"
26
27RC5Context::~RC5Context()
28{
29	memset(&rc5Key, 0, sizeof(RC5_32_KEY));
30}
31
32/*
33 * Standard CSPContext init, called from CSPFullPluginSession::init().
34 * Reusable, e.g., query followed by en/decrypt.
35 */
36void RC5Context::init(
37	const Context &context,
38	bool encrypting)
39{
40	CSSM_SIZE	keyLen;
41	uint8 		*keyData 	= NULL;
42	uint32		rounds = RC5_16_ROUNDS;
43
44	/* obtain key from context */
45	symmetricKeyBits(context, session(), CSSM_ALGID_RC5,
46		encrypting ? CSSM_KEYUSE_ENCRYPT : CSSM_KEYUSE_DECRYPT,
47		keyData, keyLen);
48	if((keyLen < RC5_MIN_KEY_SIZE_BYTES) || (keyLen > RC5_MAX_KEY_SIZE_BYTES)) {
49		CssmError::throwMe(CSSMERR_CSP_INVALID_ATTR_KEY);
50	}
51
52	/*
53	 * Optional rounds
54	 */
55	rounds = context.getInt(CSSM_ATTRIBUTE_ROUNDS);
56	if(rounds == 0) {
57		/* default */
58		rounds = RC5_16_ROUNDS;
59	}
60
61	/* init the low-level state */
62	RC5_32_set_key(&rc5Key, (int)keyLen, keyData, rounds);
63
64	/* Finally, have BlockCryptor do its setup */
65	setup(RC5_BLOCK_SIZE_BYTES, context);
66}
67
68/*
69 * Functions called by BlockCryptor
70 */
71void RC5Context::encryptBlock(
72	const void		*plainText,			// length implied (one block)
73	size_t			plainTextLen,
74	void			*cipherText,
75	size_t			&cipherTextLen,		// in/out, throws on overflow
76	bool			final)				// ignored
77{
78	if(plainTextLen != RC5_BLOCK_SIZE_BYTES) {
79		CssmError::throwMe(CSSMERR_CSP_INPUT_LENGTH_ERROR);
80	}
81	if(cipherTextLen < RC5_BLOCK_SIZE_BYTES) {
82		CssmError::throwMe(CSSMERR_CSP_OUTPUT_LENGTH_ERROR);
83	}
84
85	/*
86	 * Low-level code operates on array of unsigned 32-bit integers
87	 */
88	RC5_32_INT	d[2];
89	RC5_32_INT l;
90	const unsigned char *pt = (const unsigned char *)plainText;
91	c2l(pt, l); d[0]=l;
92	c2l(pt, l); d[1]=l;
93	RC5_32_encrypt(d, &rc5Key);
94	unsigned char *ct = (unsigned char *)cipherText;
95	l=d[0]; l2c(l, ct);
96	l=d[1]; l2c(l, ct);
97	cipherTextLen = RC5_BLOCK_SIZE_BYTES;
98}
99
100void RC5Context::decryptBlock(
101	const void		*cipherText,		// length implied (one block)
102	size_t			cipherTextLen,
103	void			*plainText,
104	size_t			&plainTextLen,		// in/out, throws on overflow
105	bool			final)				// ignored
106{
107	if(plainTextLen < RC5_BLOCK_SIZE_BYTES) {
108		CssmError::throwMe(CSSMERR_CSP_OUTPUT_LENGTH_ERROR);
109	}
110	/*
111	 * Low-level code operates on array of unsigned 32-bit integers
112	 */
113	RC5_32_INT	d[2];
114	RC5_32_INT l;
115	const unsigned char *ct = (const unsigned char *)cipherText;
116	c2l(ct, l); d[0]=l;
117	c2l(ct, l); d[1]=l;
118	RC5_32_decrypt(d, &rc5Key);
119	unsigned char *pt = (unsigned char *)plainText;
120	l=d[0]; l2c(l, pt);
121	l=d[1]; l2c(l, pt);
122	plainTextLen = RC5_BLOCK_SIZE_BYTES;
123}
124
125