generic-library/openssl
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

xts128.c: minor optimization.

Browse Source
This commit is contained in:
Andy Polyakov 2011-03-04 13:17:19 +00:00
parent 0ab8fd58e1
commit 16cb0d9591
1 changed files with 56 additions and 57 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
crypto/modes/xts128.c
View File

@ -69,6 +69,7 @@ int CRYPTO_xts128_encrypt(const XTS128_CONTEXT *ctx, u64 secno,
{
const union { long one; char little; } is_endian = {1};
union { u64 u[2]; u32 d[4]; u8 c[16]; } tweak, scratch;
unsigned int i;
if (len<16) return -1;
@ -84,7 +85,7 @@ int CRYPTO_xts128_encrypt(const XTS128_CONTEXT *ctx, u64 secno,
(*ctx->block2)(tweak.c,tweak.c,ctx->key2);
if (!enc && len%16) len-=16;
if (!enc && (len%16)) len-=16;
while (len>=16) {
#if defined(STRICT_ALIGNMENT)
@ -103,6 +104,8 @@ int CRYPTO_xts128_encrypt(const XTS128_CONTEXT *ctx, u64 secno,
out += 16;
len -= 16;
if (len==0) return 0;
if (is_endian.little) {
unsigned int carry,res;
@ -112,7 +115,7 @@ int CRYPTO_xts128_encrypt(const XTS128_CONTEXT *ctx, u64 secno,
tweak.u[1] = (tweak.u[1]<<1)|carry;
}
else {
unsigned int carry,c,i;
unsigned int carry,c;
for (carry=0,i=0;i<16;++i) {
c = tweak.c[i];
@ -122,9 +125,6 @@ int CRYPTO_xts128_encrypt(const XTS128_CONTEXT *ctx, u64 secno,
tweak.c[0] ^= 0x87&(0-carry);
}
}
if (len) {
unsigned int i;
if (enc) {
for (i=0;i<len;++i) {
u8 c = inp[i];
@ -183,7 +183,6 @@ int CRYPTO_xts128_encrypt(const XTS128_CONTEXT *ctx, u64 secno,
scratch.u[1] ^= tweak.u[1];
memcpy (out,scratch.c,16);
}
}
return 0;
}