static unsigned int
serpent_decrypt (void *ctx, byte *buffer_out, const byte *buffer_in)
{
serpent_context_t *context = ctx;
serpent_decrypt_internal (context, buffer_in, buffer_out);
return /*burn_stack*/ (2 * sizeof (serpent_block_t));
}
static void
serpent_decrypt (void *ctx, byte *buffer_out, const byte *buffer_in)
{
serpent_context_t *context = ctx;
serpent_decrypt_internal (context,
(const u32 *) buffer_in,
(u32 *) buffer_out);
_gcry_burn_stack (2 * sizeof (serpent_block_t));
}
/* Bulk decryption of complete blocks in CBC mode. This function is only
intended for the bulk encryption feature of cipher.c. */
void
_gcry_serpent_cbc_dec(void *context, unsigned char *iv,
void *outbuf_arg, const void *inbuf_arg,
size_t nblocks)
{
serpent_context_t *ctx = context;
unsigned char *outbuf = outbuf_arg;
const unsigned char *inbuf = inbuf_arg;
unsigned char savebuf[sizeof(serpent_block_t)];
int burn_stack_depth = 2 * sizeof (serpent_block_t);
#ifdef USE_AVX2
if (ctx->use_avx2)
{
int did_use_avx2 = 0;
/* Process data in 16 block chunks. */
while (nblocks >= 16)
{
_gcry_serpent_avx2_cbc_dec(ctx, outbuf, inbuf, iv);
nblocks -= 16;
outbuf += 16 * sizeof(serpent_block_t);
inbuf += 16 * sizeof(serpent_block_t);
did_use_avx2 = 1;
}
if (did_use_avx2)
{
/* serpent-avx2 assembly code does not use stack */
if (nblocks == 0)
burn_stack_depth = 0;
}
/* Use generic/sse2 code to handle smaller chunks... */
}
#endif
#ifdef USE_SSE2
{
int did_use_sse2 = 0;
/* Process data in 8 block chunks. */
while (nblocks >= 8)
{
_gcry_serpent_sse2_cbc_dec(ctx, outbuf, inbuf, iv);
nblocks -= 8;
outbuf += 8 * sizeof(serpent_block_t);
inbuf += 8 * sizeof(serpent_block_t);
did_use_sse2 = 1;
}
if (did_use_sse2)
{
/* serpent-sse2 assembly code does not use stack */
if (nblocks == 0)
burn_stack_depth = 0;
}
/* Use generic code to handle smaller chunks... */
}
#endif
#ifdef USE_NEON
if (ctx->use_neon)
{
int did_use_neon = 0;
/* Process data in 8 block chunks. */
while (nblocks >= 8)
{
_gcry_serpent_neon_cbc_dec(ctx, outbuf, inbuf, iv);
nblocks -= 8;
outbuf += 8 * sizeof(serpent_block_t);
inbuf += 8 * sizeof(serpent_block_t);
did_use_neon = 1;
}
if (did_use_neon)
{
/* serpent-neon assembly code does not use stack */
if (nblocks == 0)
burn_stack_depth = 0;
}
/* Use generic code to handle smaller chunks... */
}
#endif
for ( ;nblocks; nblocks-- )
{
/* INBUF is needed later and it may be identical to OUTBUF, so store
the intermediate result to SAVEBUF. */
serpent_decrypt_internal (ctx, inbuf, savebuf);
buf_xor_n_copy_2(outbuf, savebuf, iv, inbuf, sizeof(serpent_block_t));
inbuf += sizeof(serpent_block_t);
outbuf += sizeof(serpent_block_t);
}
wipememory(savebuf, sizeof(savebuf));
_gcry_burn_stack(burn_stack_depth);
}
static const char *
serpent_test (void)
{
serpent_context_t context;
unsigned char scratch[16];
unsigned int i;
const char *r;
static struct test
{
int key_length;
unsigned char key[32];
unsigned char text_plain[16];
unsigned char text_cipher[16];
} test_data[] =
{
{
16,
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00",
"\xD2\x9D\x57\x6F\xCE\xA3\xA3\xA7\xED\x90\x99\xF2\x92\x73\xD7\x8E",
"\xB2\x28\x8B\x96\x8A\xE8\xB0\x86\x48\xD1\xCE\x96\x06\xFD\x99\x2D"
},
{
24,
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
"\x00\x00\x00\x00\x00\x00\x00\x00",
"\xD2\x9D\x57\x6F\xCE\xAB\xA3\xA7\xED\x98\x99\xF2\x92\x7B\xD7\x8E",
"\x13\x0E\x35\x3E\x10\x37\xC2\x24\x05\xE8\xFA\xEF\xB2\xC3\xC3\xE9"
},
{
32,
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00",
"\xD0\x95\x57\x6F\xCE\xA3\xE3\xA7\xED\x98\xD9\xF2\x90\x73\xD7\x8E",
"\xB9\x0E\xE5\x86\x2D\xE6\x91\x68\xF2\xBD\xD5\x12\x5B\x45\x47\x2B"
},
{
32,
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00",
"\x00\x00\x00\x00\x01\x00\x00\x00\x02\x00\x00\x00\x03\x00\x00\x00",
"\x20\x61\xA4\x27\x82\xBD\x52\xEC\x69\x1E\xC3\x83\xB0\x3B\xA7\x7C"
},
{
0
},
};
for (i = 0; test_data[i].key_length; i++)
{
serpent_setkey_internal (&context, test_data[i].key,
test_data[i].key_length);
serpent_encrypt_internal (&context, test_data[i].text_plain, scratch);
if (memcmp (scratch, test_data[i].text_cipher, sizeof (serpent_block_t)))
switch (test_data[i].key_length)
{
case 16:
return "Serpent-128 test encryption failed.";
case 24:
return "Serpent-192 test encryption failed.";
case 32:
return "Serpent-256 test encryption failed.";
}
serpent_decrypt_internal (&context, test_data[i].text_cipher, scratch);
if (memcmp (scratch, test_data[i].text_plain, sizeof (serpent_block_t)))
switch (test_data[i].key_length)
{
case 16:
return "Serpent-128 test decryption failed.";
case 24:
return "Serpent-192 test decryption failed.";
case 32:
return "Serpent-256 test decryption failed.";
}
}
if ( (r = selftest_ctr_128 ()) )
return r;
if ( (r = selftest_cbc_128 ()) )
return r;
if ( (r = selftest_cfb_128 ()) )
return r;
return NULL;
}
