/* 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. * * Tom St Denis, tomstdenis@iahu.ca, http://libtomcrypt.org *//* PMAC implementation by Tom St Denis */#include "mycrypt.h"#ifdef PMACint pmac_done(pmac_state *state, unsigned char *out, unsigned long *outlen){   int err, x;   _ARGCHK(state != NULL);   _ARGCHK(out   != NULL);   if ((err = cipher_is_valid(state->cipher_idx)) != CRYPT_OK) {      return err;   }   if ((state->buflen > (int)sizeof(state->block)) || (state->buflen < 0) ||       (state->block_len > (int)sizeof(state->block)) || (state->buflen > state->block_len)) {      return CRYPT_INVALID_ARG;   }   /* handle padding.  If multiple xor in L/x */   if (state->buflen == state->block_len) {      /* xor Lr against the checksum */      for (x = 0; x < state->block_len; x++) {          state->checksum[x] ^= state->block[x] ^ state->Lr[x];      }   } else {      /* otherwise xor message bytes then the 0x80 byte */      for (x = 0; x < state->buflen; x++) {          state->checksum[x] ^= state->block[x];      }      state->checksum[x] ^= 0x80;   }   /* encrypt it */   cipher_descriptor[state->cipher_idx].ecb_encrypt(state->checksum, state->checksum, &state->key);   /* store it */   for (x = 0; x < state->block_len && x <= (int)*outlen; x++) {       out[x] = state->checksum[x];   }   *outlen = x;#ifdef CLEAN_STACK   zeromem(state, sizeof(*state));#endif   return CRYPT_OK;}#endif