view libtomcrypt/src/mac/pmac/pmac_done.c @ 1638:315fcba6960e

dropbearconvert: keyimport.c: fix BER encoding of secp521r1 keys (#69) keysizes >= 128 octets will be encoded with a 3 byte header which must be accounted by the optional-header Reproduce: master:~/build/dropbear$ ./dropbearkey -t ecdsa -s 521 -f K Generating 521 bit ecdsa key, this may take a while... master:~/build/dropbear$ ./dropbearconvert d o K L Key is a ecdsa-sha2-nistp521 key Wrote key to 'L' master:~/build/dropbear$ openssl ec < L read EC key unable to load Key 139769806448384:error:0D07209B:asn1 encoding routines:ASN1_get_object:too long:crypto/asn1/asn1_lib.c:91:
author Christian Hohnstädt <christian@hohnstaedt.de>
date Wed, 20 Mar 2019 16:42:47 +0100
parents 6dba84798cd5
children
line wrap: on
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/* 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_done.c
  PMAC implementation, terminate a session, by Tom St Denis
*/

#ifdef LTC_PMAC

int pmac_done(pmac_state *state, unsigned char *out, unsigned long *outlen)
{
   int err, x;

   LTC_ARGCHK(state != NULL);
   LTC_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 */
   if ((err = cipher_descriptor[state->cipher_idx].ecb_encrypt(state->checksum, state->checksum, &state->key)) != CRYPT_OK) {
      return err;
   }
   cipher_descriptor[state->cipher_idx].done(&state->key);

   /* store it */
   for (x = 0; x < state->block_len && x < (int)*outlen; x++) {
       out[x] = state->checksum[x];
   }
   *outlen = x;

#ifdef LTC_CLEAN_STACK
   zeromem(state, sizeof(*state));
#endif
   return CRYPT_OK;
}

#endif


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