/*
* alg2268.c - implementation of the algorithm in RFC 2268
*
* 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/. */
#ifdef FREEBL_NO_DEPEND
#include "stubs.h"
#endif
#include "blapi.h"
#include "blapii.h"
#include "secerr.h"
#ifdef XP_UNIX_XXX
#include <stddef.h> /* for ptrdiff_t */
#endif
/*
** RC2 symmetric block cypher
*/
typedef SECStatus(rc2Func)(RC2Context *cx, unsigned char *output,
const unsigned char *input, unsigned int inputLen);
/* forward declarations */
static rc2Func rc2_EncryptECB;
static rc2Func rc2_DecryptECB;
static rc2Func rc2_EncryptCBC;
static rc2Func rc2_DecryptCBC;
typedef union {
PRUint32 l[2];
PRUint16 s[4];
PRUint8 b[8];
} RC2Block;
struct RC2ContextStr {
union {
PRUint8 Kb[128];
PRUint16 Kw[64];
} u;
RC2Block iv;
rc2Func *enc;
rc2Func *dec;
};
#define B u.Kb
#define K u.Kw
#define BYTESWAP(x) ((x) << 8 | (x) >> 8)
#define SWAPK(i) cx->K[i] = (tmpS = cx->K[i], BYTESWAP(tmpS))
#define RC2_BLOCK_SIZE 8
#define LOAD_HARD(R) \
R[0] = (PRUint16)input[1] << 8 | input[0]; \
R[1] = (PRUint16)input[3] << 8 | input[2]; \
R[2] = (PRUint16)input[5] << 8 | input[4]; \
R[3] = (PRUint16)input[7] << 8 | input[6];
#define LOAD_EASY(R) \
R[0] = ((PRUint16 *)input)[0]; \
R[1] = ((PRUint16 *)input)[1]; \
R[2] = ((PRUint16 *)input)[2]; \
R[3] = ((PRUint16 *)input)[3];
#define STORE_HARD(R) \
output[0] = (PRUint8)(R[0]); \
output[1] = (PRUint8)(R[0] >> 8); \
output[2] = (PRUint8)(R[1]); \
output[3] = (PRUint8)(R[1] >> 8); \
output[4] = (PRUint8)(R[2]); \
output[5] = (PRUint8)(R[2] >> 8); \
output[6] = (PRUint8)(R[3]); \
output[7] = (PRUint8)(R[3] >> 8);
#define STORE_EASY(R) \
((PRUint16 *)output)[0] = R[0]; \
((PRUint16 *)output)[1] = R[1]; \
((PRUint16 *)output)[2] = R[2]; \
((PRUint16 *)output)[3] = R[3];
#if defined(NSS_X86_OR_X64)
#define LOAD(R) LOAD_EASY(R)
#define STORE(R) STORE_EASY(R)
#elif !defined(IS_LITTLE_ENDIAN)
#define LOAD(R) LOAD_HARD(R)
#define STORE(R) STORE_HARD(R)
#else
#define LOAD(R) \
if ((ptrdiff_t)input & 1) { \
LOAD_HARD(R) \
} else { \
LOAD_EASY(R) \
}
#define STORE(R) \
if ((ptrdiff_t)input & 1) { \
STORE_HARD(R) \
} else { \
STORE_EASY(R) \
}
#endif
static const PRUint8 S[256] = {
0331, 0170, 0371, 0304, 0031, 0335, 0265, 0355, 0050, 0351, 0375, 0171, 0112, 0240, 0330, 0235,
0306, 0176, 0067, 0203, 0053, 0166, 0123, 0216, 0142, 0114, 0144, 0210, 0104, 0213, 0373, 0242,
0027, 0232, 0131, 0365, 0207, 0263, 0117, 0023, 0141, 0105, 0155, 0215, 0011, 0201, 0175, 0062,
0275, 0217, 0100, 0353, 0206, 0267, 0173, 0013, 0360, 0225, 0041, 0042, 0134, 0153, 0116, 0202,
0124, 0326, 0145, 0223, 0316, 0140, 0262, 0034, 0163, 0126, 0300, 0024, 0247, 0214, 0361, 0334,
0022, 0165, 0312, 0037, 0073, 0276, 0344, 0321, 0102, 0075, 0324, 0060, 0243, 0074, 0266, 0046,
0157, 0277, 0016, 0332, 0106, 0151, 0007, 0127, 0047, 0362, 0035, 0233, 0274, 0224, 0103, 0003,
0370, 0021, 0307, 0366, 0220, 0357, 0076, 0347, 0006, 0303, 0325, 0057, 0310, 0146, 0036, 0327,
0010, 0350, 0352, 0336, 0200, 0122, 0356, 0367, 0204, 0252, 0162, 0254, 0065, 0115, 0152, 0052,
0226, 0032, 0322, 0161, 0132, 0025, 0111, 0164, 0113, 0237, 0320, 0136, 0004, 0030, 0244, 0354,
0302, 0340, 0101, 0156, 0017, 0121, 0313, 0314, 0044, 0221, 0257, 0120, 0241, 0364, 0160, 0071,
0231, 0174, 0072, 0205, 0043, 0270, 0264, 0172, 0374, 0002, 0066, 0133, 0045, 0125, 0227, 0061,
0055, 0135, 0372, 0230, 0343, 0212, 0222, 0256, 0005, 0337, 0051, 0020, 0147, 0154, 0272, 0311,
0323, 0000, 0346, 0317, 0341, 0236, 0250, 0054, 0143, 0026, 0001, 0077, 0130, 0342, 0211, 0251,
0015, 0070, 0064, 0033, 0253, 0063, 0377, 0260, 0273, 0110, 0014, 0137, 0271, 0261, 0315, 0056,
0305, 0363, 0333, 0107, 0345, 0245, 0234, 0167, 0012, 0246, 0040, 0150, 0376, 0177, 0301, 0255
};
RC2Context *
RC2_AllocateContext(void)
{
return PORT_ZNew(RC2Context);
}
SECStatus
RC2_InitContext(RC2Context *cx, const unsigned char *key, unsigned int len,
const unsigned char *input, int mode, unsigned int efLen8,
unsigned int unused)
{
PRUint8 *L, *L2;
int i;
#if !defined(IS_LITTLE_ENDIAN)
PRUint16 tmpS;
#endif
PRUint8 tmpB;
if (!key || !cx || !len || len > (sizeof cx->B) ||
efLen8 > (sizeof cx->B)) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
if (mode == NSS_RC2) {
/* groovy */
} else if (mode == NSS_RC2_CBC) {
if (!input) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
} else {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
if (mode == NSS_RC2_CBC) {
cx->enc = &rc2_EncryptCBC;
cx->dec = &rc2_DecryptCBC;
LOAD(cx->iv.s);
} else {
cx->enc = &rc2_EncryptECB;
cx->dec = &rc2_DecryptECB;
}
/* Step 0. Copy key into table. */
memcpy(cx->B, key, len);
/* Step 1. Compute all values to the right of the key. */
L2 = cx->B;
L = L2 + len;
tmpB = L[-1];
for (i = (sizeof cx->B) - len; i > 0; --i) {
*L++ = tmpB = S[(PRUint8)(tmpB + *L2++)];
}
/* step 2. Adjust left most byte of effective key. */
i = (sizeof cx->B) - efLen8;
L = cx->B + i;
*L = tmpB = S[*L]; /* mask is always 0xff */
/* step 3. Recompute all values to the left of effective key. */
L2 = --L + efLen8;
while (L >= cx->B) {
*L-- = tmpB = S[tmpB ^ *L2--];
}
#if !defined(IS_LITTLE_ENDIAN)
for (i = 63; i >= 0; --i) {
SWAPK(i); /* candidate for unrolling */
}
#endif
return SECSuccess;
}
/*
** Create a new RC2 context suitable for RC2 encryption/decryption.
** "key" raw key data
** "len" the number of bytes of key data
** "iv" is the CBC initialization vector (if mode is NSS_RC2_CBC)
** "mode" one of NSS_RC2 or NSS_RC2_CBC
** "effectiveKeyLen" in bytes, not bits.
**
** When mode is set to NSS_RC2_CBC the RC2 cipher is run in "cipher block
** chaining" mode.
*/
RC2Context *
RC2_CreateContext(const unsigned char *key, unsigned int len,
const unsigned char *iv, int mode, unsigned efLen8)
{
RC2Context *cx = PORT_ZNew(RC2Context);
if (cx) {
SECStatus rv = RC2_InitContext(cx, key, len, iv, mode, efLen8, 0);
if (rv != SECSuccess) {
RC2_DestroyContext(cx, PR_TRUE);
cx = NULL;
}
}
return cx;
}
/*
** Destroy an RC2 encryption/decryption context.
** "cx" the context
** "freeit" if PR_TRUE then free the object as well as its sub-objects
*/
void
RC2_DestroyContext(RC2Context *cx, PRBool freeit)
{
if (cx) {
memset(cx, 0, sizeof *cx);
if (freeit) {
PORT_Free(cx);
}
}
}
#define ROL(x, k) (x << k | x >> (16 - k))
#define MIX(j) \
R0 = R0 + cx->K[4 * j + 0] + (R3 & R2) + (~R3 & R1); \
R0 = ROL(R0, 1); \
R1 = R1 + cx->K[4 * j + 1] + (R0 & R3) + (~R0 & R2); \
R1 = ROL(R1, 2); \
R2 = R2 + cx->K[4 * j + 2] + (R1 & R0) + (~R1 & R3); \
R2 = ROL(R2, 3); \
R3 = R3 + cx->K[4 * j + 3] + (R2 & R1) + (~R2 & R0); \
R3 = ROL(R3, 5)
#define MASH \
R0 = R0 + cx->K[R3 & 63]; \
R1 = R1 + cx->K[R0 & 63]; \
R2 = R2 + cx->K[R1 & 63]; \
R3 = R3 + cx->K[R2 & 63]
/* Encrypt one block */
static void
rc2_Encrypt1Block(RC2Context *cx, RC2Block *output, RC2Block *input)
{
register PRUint16 R0, R1, R2, R3;
/* step 1. Initialize input. */
R0 = input->s[0];
R1 = input->s[1];
R2 = input->s[2];
R3 = input->s[3];
/* step 2. Expand Key (already done, in context) */
/* step 3. j = 0 */
/* step 4. Perform 5 mixing rounds. */
MIX(0);
MIX(1);
MIX(2);
MIX(3);
MIX(4);
/* step 5. Perform 1 mashing round. */
MASH;
/* step 6. Perform 6 mixing rounds. */
MIX(5);
MIX(6);
MIX(7);
MIX(8);
MIX(9);
MIX(10);
/* step 7. Perform 1 mashing round. */
MASH;
/* step 8. Perform 5 mixing rounds. */
MIX(11);
MIX(12);
MIX(13);
MIX(14);
MIX(15);
/* output results */
output->s[0] = R0;
output->s[1] = R1;
output->s[2] = R2;
output->s[3] = R3;
}
#define ROR(x, k) (x >> k | x << (16 - k))
#define R_MIX(j) \
R3 = ROR(R3, 5); \
R3 = R3 - cx->K[4 * j + 3] - (R2 & R1) - (~R2 & R0); \
R2 = ROR(R2, 3); \
R2 = R2 - cx->K[4 * j + 2] - (R1 & R0) - (~R1 & R3); \
R1 = ROR(R1, 2); \
R1 = R1 - cx->K[4 * j + 1] - (R0 & R3) - (~R0 & R2); \
R0 = ROR(R0, 1); \
R0 = R0 - cx->K[4 * j + 0] - (R3 & R2) - (~R3 & R1)
#define R_MASH \
R3 = R3 - cx->K[R2 & 63]; \
R2 = R2 - cx->K[R1 & 63]; \
R1 = R1 - cx->K[R0 & 63]; \
R0 = R0 - cx->K[R3 & 63]
/* Encrypt one block */
static void
rc2_Decrypt1Block(RC2Context *cx, RC2Block *output, RC2Block *input)
{
register PRUint16 R0, R1, R2, R3;
/* step 1. Initialize input. */
R0 = input->s[0];
R1 = input->s[1];
R2 = input->s[2];
R3 = input->s[3];
/* step 2. Expand Key (already done, in context) */
/* step 3. j = 63 */
/* step 4. Perform 5 r_mixing rounds. */
R_MIX(15);
R_MIX(14);
R_MIX(13);
R_MIX(12);
R_MIX(11);
/* step 5. Perform 1 r_mashing round. */
R_MASH;
/* step 6. Perform 6 r_mixing rounds. */
R_MIX(10);
R_MIX(9);
R_MIX(8);
R_MIX(7);
R_MIX(6);
R_MIX(5);
/* step 7. Perform 1 r_mashing round. */
R_MASH;
/* step 8. Perform 5 r_mixing rounds. */
R_MIX(4);
R_MIX(3);
R_MIX(2);
R_MIX(1);
R_MIX(0);
/* output results */
output->s[0] = R0;
output->s[1] = R1;
output->s[2] = R2;
output->s[3] = R3;
}
static SECStatus NO_SANITIZE_ALIGNMENT
rc2_EncryptECB(RC2Context *cx, unsigned char *output,
const unsigned char *input, unsigned int inputLen)
{
RC2Block iBlock;
while (inputLen > 0) {
LOAD(iBlock.s)
rc2_Encrypt1Block(cx, &iBlock, &iBlock);
STORE(iBlock.s)
output += RC2_BLOCK_SIZE;
input += RC2_BLOCK_SIZE;
inputLen -= RC2_BLOCK_SIZE;
}
return SECSuccess;
}
static SECStatus NO_SANITIZE_ALIGNMENT
rc2_DecryptECB(RC2Context *cx, unsigned char *output,
const unsigned char *input, unsigned int inputLen)
{
RC2Block iBlock;
while (inputLen > 0) {
LOAD(iBlock.s)
rc2_Decrypt1Block(cx, &iBlock, &iBlock);
STORE(iBlock.s)
output += RC2_BLOCK_SIZE;
input += RC2_BLOCK_SIZE;
inputLen -= RC2_BLOCK_SIZE;
}
return SECSuccess;
}
static SECStatus NO_SANITIZE_ALIGNMENT
rc2_EncryptCBC(RC2Context *cx, unsigned char *output,
const unsigned char *input, unsigned int inputLen)
{
RC2Block iBlock;
while (inputLen > 0) {
LOAD(iBlock.s)
iBlock.l[0] ^= cx->iv.l[0];
iBlock.l[1] ^= cx->iv.l[1];
rc2_Encrypt1Block(cx, &iBlock, &iBlock);
cx->iv = iBlock;
STORE(iBlock.s)
output += RC2_BLOCK_SIZE;
input += RC2_BLOCK_SIZE;
inputLen -= RC2_BLOCK_SIZE;
}
return SECSuccess;
}
static SECStatus NO_SANITIZE_ALIGNMENT
rc2_DecryptCBC(RC2Context *cx, unsigned char *output,
const unsigned char *input, unsigned int inputLen)
{
RC2Block iBlock;
RC2Block oBlock;
while (inputLen > 0) {
LOAD(iBlock.s)
rc2_Decrypt1Block(cx, &oBlock, &iBlock);
oBlock.l[0] ^= cx->iv.l[0];
oBlock.l[1] ^= cx->iv.l[1];
cx->iv = iBlock;
STORE(oBlock.s)
output += RC2_BLOCK_SIZE;
input += RC2_BLOCK_SIZE;
inputLen -= RC2_BLOCK_SIZE;
}
return SECSuccess;
}
/*
** Perform RC2 encryption.
** "cx" the context
** "output" the output buffer to store the encrypted data.
** "outputLen" how much data is stored in "output". Set by the routine
** after some data is stored in output.
** "maxOutputLen" the maximum amount of data that can ever be
** stored in "output"
** "input" the input data
** "inputLen" the amount of input data
*/
SECStatus
RC2_Encrypt(RC2Context *cx, unsigned char *output,
unsigned int *outputLen, unsigned int maxOutputLen,
const unsigned char *input, unsigned int inputLen)
{
SECStatus rv = SECSuccess;
if (inputLen) {
if (inputLen % RC2_BLOCK_SIZE) {
PORT_SetError(SEC_ERROR_INPUT_LEN);
return SECFailure;
}
if (maxOutputLen < inputLen) {
PORT_SetError(SEC_ERROR_OUTPUT_LEN);
return SECFailure;
}
rv = (*cx->enc)(cx, output, input, inputLen);
}
if (rv == SECSuccess) {
*outputLen = inputLen;
}
return rv;
}
/*
** Perform RC2 decryption.
** "cx" the context
** "output" the output buffer to store the decrypted data.
** "outputLen" how much data is stored in "output". Set by the routine
** after some data is stored in output.
** "maxOutputLen" the maximum amount of data that can ever be
** stored in "output"
** "input" the input data
** "inputLen" the amount of input data
*/
SECStatus
RC2_Decrypt(RC2Context *cx, unsigned char *output,
unsigned int *outputLen, unsigned int maxOutputLen,
const unsigned char *input, unsigned int inputLen)
{
SECStatus rv = SECSuccess;
if (inputLen) {
if (inputLen % RC2_BLOCK_SIZE) {
PORT_SetError(SEC_ERROR_INPUT_LEN);
return SECFailure;
}
if (maxOutputLen < inputLen) {
PORT_SetError(SEC_ERROR_OUTPUT_LEN);
return SECFailure;
}
rv = (*cx->dec)(cx, output, input, inputLen);
}
if (rv == SECSuccess) {
*outputLen = inputLen;
}
return rv;
}