+++ /dev/null
-/* LibTomCrypt, modular cryptographic library -- Tom St Denis
- *
- * LibTomCrypt is a library that provides various cryptographic
- * algorithms in a highly modular and flexible manner.
- *
- * The library is free for all purposes without any express
- * guarantee it works.
- */
-#include "tomcrypt.h"
-
-/**
- @file pmac_init.c
- PMAC implementation, initialize state, by Tom St Denis
-*/
-
-#ifdef LTC_PMAC
-
-static const struct {
- int len;
- unsigned char poly_div[MAXBLOCKSIZE],
- poly_mul[MAXBLOCKSIZE];
-} polys[] = {
-{
- 8,
- { 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0D },
- { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1B }
-}, {
- 16,
- { 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
- 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x43 },
- { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
- 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x87 }
-}
-};
-
-/**
- Initialize a PMAC state
- @param pmac The PMAC state to initialize
- @param cipher The index of the desired cipher
- @param key The secret key
- @param keylen The length of the secret key (octets)
- @return CRYPT_OK if successful
-*/
-int pmac_init(pmac_state *pmac, int cipher, const unsigned char *key, unsigned long keylen)
-{
- int poly, x, y, m, err;
- unsigned char *L;
-
- LTC_ARGCHK(pmac != NULL);
- LTC_ARGCHK(key != NULL);
-
- /* valid cipher? */
- if ((err = cipher_is_valid(cipher)) != CRYPT_OK) {
- return err;
- }
-
- /* determine which polys to use */
- pmac->block_len = cipher_descriptor[cipher].block_length;
- for (poly = 0; poly < (int)(sizeof(polys)/sizeof(polys[0])); poly++) {
- if (polys[poly].len == pmac->block_len) {
- break;
- }
- }
- if (poly >= (int)(sizeof(polys)/sizeof(polys[0]))) {
- return CRYPT_INVALID_ARG;
- }
- if (polys[poly].len != pmac->block_len) {
- return CRYPT_INVALID_ARG;
- }
-
-#ifdef LTC_FAST
- if (pmac->block_len % sizeof(LTC_FAST_TYPE)) {
- return CRYPT_INVALID_ARG;
- }
-#endif
-
-
- /* schedule the key */
- if ((err = cipher_descriptor[cipher].setup(key, keylen, 0, &pmac->key)) != CRYPT_OK) {
- return err;
- }
-
- /* allocate L */
- L = XMALLOC(pmac->block_len);
- if (L == NULL) {
- return CRYPT_MEM;
- }
-
- /* find L = E[0] */
- zeromem(L, pmac->block_len);
- if ((err = cipher_descriptor[cipher].ecb_encrypt(L, L, &pmac->key)) != CRYPT_OK) {
- goto error;
- }
-
- /* find Ls[i] = L << i for i == 0..31 */
- XMEMCPY(pmac->Ls[0], L, pmac->block_len);
- for (x = 1; x < 32; x++) {
- m = pmac->Ls[x-1][0] >> 7;
- for (y = 0; y < pmac->block_len-1; y++) {
- pmac->Ls[x][y] = ((pmac->Ls[x-1][y] << 1) | (pmac->Ls[x-1][y+1] >> 7)) & 255;
- }
- pmac->Ls[x][pmac->block_len-1] = (pmac->Ls[x-1][pmac->block_len-1] << 1) & 255;
-
- if (m == 1) {
- for (y = 0; y < pmac->block_len; y++) {
- pmac->Ls[x][y] ^= polys[poly].poly_mul[y];
- }
- }
- }
-
- /* find Lr = L / x */
- m = L[pmac->block_len-1] & 1;
-
- /* shift right */
- for (x = pmac->block_len - 1; x > 0; x--) {
- pmac->Lr[x] = ((L[x] >> 1) | (L[x-1] << 7)) & 255;
- }
- pmac->Lr[0] = L[0] >> 1;
-
- if (m == 1) {
- for (x = 0; x < pmac->block_len; x++) {
- pmac->Lr[x] ^= polys[poly].poly_div[x];
- }
- }
-
- /* zero buffer, counters, etc... */
- pmac->block_index = 1;
- pmac->cipher_idx = cipher;
- pmac->buflen = 0;
- zeromem(pmac->block, sizeof(pmac->block));
- zeromem(pmac->Li, sizeof(pmac->Li));
- zeromem(pmac->checksum, sizeof(pmac->checksum));
- err = CRYPT_OK;
-error:
-#ifdef LTC_CLEAN_STACK
- zeromem(L, pmac->block_len);
-#endif
-
- XFREE(L);
-
- return err;
-}
-
-#endif
-
-/* ref: $Format:%D$ */
-/* git commit: $Format:%H$ */
-/* commit time: $Format:%ai$ */