gcry_error_t
gcry_cipher_ctl( gcry_cipher_hd_t h, int cmd, void *buffer, size_t buflen)
{
gcry_err_code_t rc = GPG_ERR_NO_ERROR;
switch (cmd)
{
case GCRYCTL_SET_KEY:
rc = cipher_setkey( h, buffer, buflen );
break;
case GCRYCTL_SET_IV:
cipher_setiv( h, buffer, buflen );
break;
case GCRYCTL_RESET:
cipher_reset (h);
break;
case GCRYCTL_CFB_SYNC:
cipher_sync( h );
break;
case GCRYCTL_SET_CBC_CTS:
if (buflen)
if (h->flags & GCRY_CIPHER_CBC_MAC)
rc = GPG_ERR_INV_FLAG;
else
h->flags |= GCRY_CIPHER_CBC_CTS;
else
h->flags &= ~GCRY_CIPHER_CBC_CTS;
break;
case GCRYCTL_SET_CBC_MAC:
if (buflen)
if (h->flags & GCRY_CIPHER_CBC_CTS)
rc = GPG_ERR_INV_FLAG;
else
h->flags |= GCRY_CIPHER_CBC_MAC;
else
h->flags &= ~GCRY_CIPHER_CBC_MAC;
break;
case GCRYCTL_DISABLE_ALGO:
/* this one expects a NULL handle and buffer pointing to an
* integer with the algo number.
*/
if( h || !buffer || buflen != sizeof(int) )
return gcry_error (GPG_ERR_CIPHER_ALGO);
disable_cipher_algo( *(int*)buffer );
break;
case GCRYCTL_SET_CTR:
if (buffer && buflen == h->cipher->blocksize)
memcpy (h->ctr, buffer, h->cipher->blocksize);
else if (buffer == NULL || buflen == 0)
memset (h->ctr, 0, h->cipher->blocksize);
else
rc = GPG_ERR_INV_ARG;
break;
default:
rc = GPG_ERR_INV_OP;
}
return gcry_error (rc);
}
static void
write_header( cipher_filter_context_t *cfx, IOBUF a )
{
PACKET pkt;
PKT_encrypted ed;
byte temp[18];
unsigned blocksize;
unsigned nprefix;
blocksize = cipher_get_blocksize( cfx->dek->algo );
if( blocksize < 8 || blocksize > 16 )
log_fatal("unsupported blocksize %u\n", blocksize );
memset( &ed, 0, sizeof ed );
ed.len = cfx->datalen;
ed.extralen = blocksize+2;
ed.new_ctb = !ed.len && !RFC1991;
if( cfx->dek->use_mdc ) {
ed.mdc_method = DIGEST_ALGO_SHA1;
cfx->mdc_hash = md_open( DIGEST_ALGO_SHA1, 0 );
if ( DBG_HASHING )
md_start_debug( cfx->mdc_hash, "creatmdc" );
}
{
char buf[20];
sprintf (buf, "%d %d", ed.mdc_method, cfx->dek->algo);
write_status_text (STATUS_BEGIN_ENCRYPTION, buf);
}
init_packet( &pkt );
pkt.pkttype = cfx->dek->use_mdc? PKT_ENCRYPTED_MDC : PKT_ENCRYPTED;
pkt.pkt.encrypted = &ed;
if( build_packet( a, &pkt ))
log_bug("build_packet(ENCR_DATA) failed\n");
nprefix = blocksize;
randomize_buffer( temp, nprefix, 1 );
temp[nprefix] = temp[nprefix-2];
temp[nprefix+1] = temp[nprefix-1];
print_cipher_algo_note( cfx->dek->algo );
cfx->cipher_hd = cipher_open( cfx->dek->algo,
cfx->dek->use_mdc? CIPHER_MODE_CFB
: CIPHER_MODE_AUTO_CFB, 1 );
/* log_hexdump( "thekey", cfx->dek->key, cfx->dek->keylen );*/
cipher_setkey( cfx->cipher_hd, cfx->dek->key, cfx->dek->keylen );
cipher_setiv( cfx->cipher_hd, NULL, 0 );
/* log_hexdump( "prefix", temp, nprefix+2 ); */
if( cfx->mdc_hash ) /* hash the "IV" */
md_write( cfx->mdc_hash, temp, nprefix+2 );
cipher_encrypt( cfx->cipher_hd, temp, temp, nprefix+2);
cipher_sync( cfx->cipher_hd );
iobuf_write(a, temp, nprefix+2);
cfx->header=1;
}
gcry_err_code_t
_gcry_cipher_ctl (gcry_cipher_hd_t h, int cmd, void *buffer, size_t buflen)
{
gcry_err_code_t rc = 0;
switch (cmd)
{
case GCRYCTL_RESET:
cipher_reset (h);
break;
case GCRYCTL_FINALIZE:
if (!h || buffer || buflen)
return GPG_ERR_INV_ARG;
h->marks.finalize = 1;
break;
case GCRYCTL_CFB_SYNC:
cipher_sync( h );
break;
case GCRYCTL_SET_CBC_CTS:
if (buflen)
if (h->flags & GCRY_CIPHER_CBC_MAC)
rc = GPG_ERR_INV_FLAG;
else
h->flags |= GCRY_CIPHER_CBC_CTS;
else
h->flags &= ~GCRY_CIPHER_CBC_CTS;
break;
case GCRYCTL_SET_CBC_MAC:
if (buflen)
if (h->flags & GCRY_CIPHER_CBC_CTS)
rc = GPG_ERR_INV_FLAG;
else
h->flags |= GCRY_CIPHER_CBC_MAC;
else
h->flags &= ~GCRY_CIPHER_CBC_MAC;
break;
case GCRYCTL_SET_CCM_LENGTHS:
#ifdef HAVE_U64_TYPEDEF
{
u64 params[3];
size_t encryptedlen;
size_t aadlen;
size_t authtaglen;
if (h->mode != GCRY_CIPHER_MODE_CCM)
return GPG_ERR_INV_CIPHER_MODE;
if (!buffer || buflen != 3 * sizeof(u64))
return GPG_ERR_INV_ARG;
/* This command is used to pass additional length parameters needed
by CCM mode to initialize CBC-MAC. */
memcpy (params, buffer, sizeof(params));
encryptedlen = params[0];
aadlen = params[1];
authtaglen = params[2];
rc = _gcry_cipher_ccm_set_lengths (h, encryptedlen, aadlen, authtaglen);
}
#else
rc = GPG_ERR_NOT_SUPPORTED;
#endif
break;
case GCRYCTL_SET_TAGLEN:
if (!h || !buffer || buflen != sizeof(int) )
return GPG_ERR_INV_ARG;
switch (h->mode)
{
case GCRY_CIPHER_MODE_OCB:
switch (*(int*)buffer)
{
case 8: case 12: case 16:
h->u_mode.ocb.taglen = *(int*)buffer;
break;
default:
rc = GPG_ERR_INV_LENGTH; /* Invalid tag length. */
break;
}
break;
default:
rc =GPG_ERR_INV_CIPHER_MODE;
break;
}
break;
case GCRYCTL_DISABLE_ALGO:
/* This command expects NULL for H and BUFFER to point to an
integer with the algo number. */
if( h || !buffer || buflen != sizeof(int) )
return GPG_ERR_CIPHER_ALGO;
disable_cipher_algo( *(int*)buffer );
break;
case PRIV_CIPHERCTL_DISABLE_WEAK_KEY: /* (private) */
if (h->spec->set_extra_info)
rc = h->spec->set_extra_info
(&h->context.c, CIPHER_INFO_NO_WEAK_KEY, NULL, 0);
else
rc = GPG_ERR_NOT_SUPPORTED;
break;
case PRIV_CIPHERCTL_GET_INPUT_VECTOR: /* (private) */
/* This is the input block as used in CFB and OFB mode which has
initially been set as IV. The returned format is:
1 byte Actual length of the block in bytes.
n byte The block.
If the provided buffer is too short, an error is returned. */
if (buflen < (1 + h->spec->blocksize))
rc = GPG_ERR_TOO_SHORT;
else
{
unsigned char *ivp;
unsigned char *dst = buffer;
int n = h->unused;
if (!n)
n = h->spec->blocksize;
gcry_assert (n <= h->spec->blocksize);
*dst++ = n;
ivp = h->u_iv.iv + h->spec->blocksize - n;
while (n--)
*dst++ = *ivp++;
}
break;
case GCRYCTL_SET_SBOX:
if (h->spec->set_extra_info)
rc = h->spec->set_extra_info
(&h->context.c, GCRYCTL_SET_SBOX, buffer, buflen);
else
rc = GPG_ERR_NOT_SUPPORTED;
break;
default:
rc = GPG_ERR_INV_OP;
}
return rc;
}
gcry_error_t
gcry_cipher_ctl( gcry_cipher_hd_t h, int cmd, void *buffer, size_t buflen)
{
gcry_err_code_t rc = GPG_ERR_NO_ERROR;
switch (cmd)
{
case GCRYCTL_SET_KEY: /* Deprecated; use gcry_cipher_setkey. */
rc = cipher_setkey( h, buffer, buflen );
break;
case GCRYCTL_SET_IV: /* Deprecated; use gcry_cipher_setiv. */
cipher_setiv( h, buffer, buflen );
break;
case GCRYCTL_RESET:
cipher_reset (h);
break;
case GCRYCTL_CFB_SYNC:
cipher_sync( h );
break;
case GCRYCTL_SET_CBC_CTS:
if (buflen)
if (h->flags & GCRY_CIPHER_CBC_MAC)
rc = GPG_ERR_INV_FLAG;
else
h->flags |= GCRY_CIPHER_CBC_CTS;
else
h->flags &= ~GCRY_CIPHER_CBC_CTS;
break;
case GCRYCTL_SET_CBC_MAC:
if (buflen)
if (h->flags & GCRY_CIPHER_CBC_CTS)
rc = GPG_ERR_INV_FLAG;
else
h->flags |= GCRY_CIPHER_CBC_MAC;
else
h->flags &= ~GCRY_CIPHER_CBC_MAC;
break;
case GCRYCTL_DISABLE_ALGO:
/* This command expects NULL for H and BUFFER to point to an
integer with the algo number. */
if( h || !buffer || buflen != sizeof(int) )
return gcry_error (GPG_ERR_CIPHER_ALGO);
disable_cipher_algo( *(int*)buffer );
break;
case GCRYCTL_SET_CTR: /* Deprecated; use gcry_cipher_setctr. */
rc = gpg_err_code (_gcry_cipher_setctr (h, buffer, buflen));
break;
case 61: /* Disable weak key detection (private). */
if (h->extraspec->set_extra_info)
rc = h->extraspec->set_extra_info
(&h->context.c, CIPHER_INFO_NO_WEAK_KEY, NULL, 0);
else
rc = GPG_ERR_NOT_SUPPORTED;
break;
case 62: /* Return current input vector (private). */
/* This is the input block as used in CFB and OFB mode which has
initially been set as IV. The returned format is:
1 byte Actual length of the block in bytes.
n byte The block.
If the provided buffer is too short, an error is returned. */
if (buflen < (1 + h->cipher->blocksize))
rc = GPG_ERR_TOO_SHORT;
else
{
unsigned char *ivp;
unsigned char *dst = buffer;
int n = h->unused;
if (!n)
n = h->cipher->blocksize;
gcry_assert (n <= h->cipher->blocksize);
*dst++ = n;
ivp = h->u_iv.iv + h->cipher->blocksize - n;
while (n--)
*dst++ = *ivp++;
}
break;
default:
rc = GPG_ERR_INV_OP;
}
return gcry_error (rc);
}
