diff options
Diffstat (limited to 'cipher/cipher-ocb.c')
| -rw-r--r-- | cipher/cipher-ocb.c | 84 |
1 files changed, 55 insertions, 29 deletions
diff --git a/cipher/cipher-ocb.c b/cipher/cipher-ocb.c index 62e79bbd..bc6fd87f 100644 --- a/cipher/cipher-ocb.c +++ b/cipher/cipher-ocb.c @@ -115,8 +115,8 @@ bit_copy (unsigned char *d, const unsigned char *s, every 65536-th block. L_TMP is a helper buffer of size OCB_BLOCK_LEN which is used to hold the computation if not taken from the table. */ -static const unsigned char * -get_l (gcry_cipher_hd_t c, unsigned char *l_tmp, u64 n) +const unsigned char * +_gcry_cipher_ocb_get_l (gcry_cipher_hd_t c, unsigned char *l_tmp, u64 n) { int ntz = _gcry_ctz64 (n); @@ -257,6 +257,15 @@ _gcry_cipher_ocb_authenticate (gcry_cipher_hd_t c, const unsigned char *abuf, if (!abuflen) return 0; + /* Use a bulk method if available. */ + if (abuflen >= OCB_BLOCK_LEN && c->bulk.ocb_auth) + { + size_t nblks = abuflen / OCB_BLOCK_LEN; + c->bulk.ocb_auth (c, abuf, nblks); + abuf += nblks * OCB_BLOCK_LEN; + abuflen -= nblks * OCB_BLOCK_LEN; + } + /* Hash all full blocks. */ while (abuflen >= OCB_BLOCK_LEN) { @@ -264,7 +273,8 @@ _gcry_cipher_ocb_authenticate (gcry_cipher_hd_t c, const unsigned char *abuf, /* Offset_i = Offset_{i-1} xor L_{ntz(i)} */ buf_xor_1 (c->u_mode.ocb.aad_offset, - get_l (c, l_tmp, c->u_mode.ocb.aad_nblocks), OCB_BLOCK_LEN); + _gcry_cipher_ocb_get_l (c, l_tmp, c->u_mode.ocb.aad_nblocks), + OCB_BLOCK_LEN); /* Sum_i = Sum_{i-1} xor ENCIPHER(K, A_i xor Offset_i) */ buf_xor (l_tmp, c->u_mode.ocb.aad_offset, abuf, OCB_BLOCK_LEN); c->spec->encrypt (&c->context.c, l_tmp, l_tmp); @@ -341,40 +351,56 @@ ocb_crypt (gcry_cipher_hd_t c, int encrypt, else if ((inbuflen % OCB_BLOCK_LEN)) return GPG_ERR_INV_LENGTH; /* We support only full blocks for now. */ - if (encrypt) + /* Use a bulk method if available. */ + if (nblks && c->bulk.ocb_crypt) { - /* Checksum_i = Checksum_{i-1} xor P_i */ - ocb_checksum (c->u_ctr.ctr, inbuf, nblks); + c->bulk.ocb_crypt (c, outbuf, inbuf, nblks, encrypt); + inbuf += nblks * OCB_BLOCK_LEN; + outbuf += nblks * OCB_BLOCK_LEN; + inbuflen -= nblks * OCB_BLOCK_LEN; + outbuflen -= nblks * OCB_BLOCK_LEN; + nblks = 0; } - /* Encrypt all full blocks. */ - while (inbuflen >= OCB_BLOCK_LEN) + if (nblks) { - c->u_mode.ocb.data_nblocks++; + gcry_cipher_encrypt_t crypt_fn = + encrypt ? c->spec->encrypt : c->spec->decrypt; - /* Offset_i = Offset_{i-1} xor L_{ntz(i)} */ - buf_xor_1 (c->u_iv.iv, - get_l (c, l_tmp, c->u_mode.ocb.data_nblocks), OCB_BLOCK_LEN); - /* C_i = Offset_i xor ENCIPHER(K, P_i xor Offset_i) */ - buf_xor (outbuf, c->u_iv.iv, inbuf, OCB_BLOCK_LEN); if (encrypt) - nburn = c->spec->encrypt (&c->context.c, outbuf, outbuf); - else - nburn = c->spec->decrypt (&c->context.c, outbuf, outbuf); - burn = nburn > burn ? nburn : burn; - buf_xor_1 (outbuf, c->u_iv.iv, OCB_BLOCK_LEN); + { + /* Checksum_i = Checksum_{i-1} xor P_i */ + ocb_checksum (c->u_ctr.ctr, inbuf, nblks); + } - inbuf += OCB_BLOCK_LEN; - inbuflen -= OCB_BLOCK_LEN; - outbuf += OCB_BLOCK_LEN; - outbuflen =- OCB_BLOCK_LEN; - } + /* Encrypt all full blocks. */ + while (inbuflen >= OCB_BLOCK_LEN) + { + c->u_mode.ocb.data_nblocks++; + + /* Offset_i = Offset_{i-1} xor L_{ntz(i)} */ + buf_xor_1 (c->u_iv.iv, + _gcry_cipher_ocb_get_l (c, l_tmp, + c->u_mode.ocb.data_nblocks), + OCB_BLOCK_LEN); + /* C_i = Offset_i xor ENCIPHER(K, P_i xor Offset_i) */ + buf_xor (outbuf, c->u_iv.iv, inbuf, OCB_BLOCK_LEN); + nburn = crypt_fn (&c->context.c, outbuf, outbuf); + burn = nburn > burn ? nburn : burn; + buf_xor_1 (outbuf, c->u_iv.iv, OCB_BLOCK_LEN); + + inbuf += OCB_BLOCK_LEN; + inbuflen -= OCB_BLOCK_LEN; + outbuf += OCB_BLOCK_LEN; + outbuflen =- OCB_BLOCK_LEN; + } - if (!encrypt) - { - /* Checksum_i = Checksum_{i-1} xor P_i */ - ocb_checksum (c->u_ctr.ctr, outbuf - nblks * OCB_BLOCK_LEN, nblks); - } + if (!encrypt) + { + /* Checksum_i = Checksum_{i-1} xor P_i */ + ocb_checksum (c->u_ctr.ctr, outbuf - nblks * OCB_BLOCK_LEN, nblks); + } + } /* Encrypt final partial block. Note that we expect INBUFLEN to be shorter than OCB_BLOCK_LEN (see above). */ |