#endif
#include <assert.h>
-typedef struct {
- void *key1, *key2;
- block128_f block1,block2;
-} XTS128_CONTEXT;
-
-int CRYPTO_xts128_encrypt(const XTS128_CONTEXT *ctx, u64 secno,
+int CRYPTO_xts128_encrypt(const XTS128_CONTEXT *ctx, const unsigned char iv[16],
const unsigned char *inp, unsigned char *out,
size_t len, int enc)
{
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;
- if (is_endian.little) {
- tweak.u[0] = secno;
- tweak.u[1] = 0;
- }
- else {
- PUTU32(tweak.c,secno);
- PUTU32(tweak.c+4,secno>>32);
- tweak.u[1] = 0;
- }
+ memcpy(tweak.c, iv, 16);
(*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)
scratch.u[1] = ((u64*)inp)[1]^tweak.u[1];
#endif
(*ctx->block1)(scratch.c,scratch.c,ctx->key1);
+#if defined(STRICT_ALIGNMENT)
scratch.u[0] ^= tweak.u[0];
scratch.u[1] ^= tweak.u[1];
memcpy(out,scratch.c,16);
+#else
+ ((u64*)out)[0] = scratch.u[0]^=tweak.u[0];
+ ((u64*)out)[1] = scratch.u[1]^=tweak.u[1];
+#endif
inp += 16;
out += 16;
len -= 16;
+ if (len==0) return 0;
+
if (is_endian.little) {
unsigned int carry,res;
res = 0x87&(((int)tweak.d[3])>>31);
- carry = tweak.u[0]>>63;
+ carry = (unsigned int)(tweak.u[0]>>63);
tweak.u[0] = (tweak.u[0]<<1)^res;
tweak.u[1] = (tweak.u[1]<<1)|carry;
}
else {
- unsigned int carry,c,i;
+ size_t c;
- for (carry=0,i=0;i<16;++i) {
- c = tweak.c[i];
- tweak.c[i] = (c<<1)|carry;
- carry = c>>7;
+ for (c=0,i=0;i<16;++i) {
+ /*+ substitutes for |, because c is 1 bit */
+ c += ((size_t)tweak.c[i])<<1;
+ tweak.c[i] = (u8)c;
+ c = c>>8;
}
- tweak.c[0] ^= 0x87&(0-carry);
+ tweak.c[0] ^= (u8)(0x87&(0-c));
}
}
- if (len) {
- unsigned int i;
-
- if (enc) {
- for (i=0;i<len;++i) {
- u8 c = inp[i];
- out[i] = scratch.c[i];
- scratch.c[i] = c;
- }
- scratch.u[0] ^= tweak.u[0];
- scratch.u[1] ^= tweak.u[1];
- (*ctx->block1)(scratch.c,scratch.c,ctx->key1);
- scratch.u[0] ^= tweak.u[0];
- scratch.u[1] ^= tweak.u[1];
- memcpy(out-16,scratch.c,16);
+ if (enc) {
+ for (i=0;i<len;++i) {
+ u8 c = inp[i];
+ out[i] = scratch.c[i];
+ scratch.c[i] = c;
+ }
+ scratch.u[0] ^= tweak.u[0];
+ scratch.u[1] ^= tweak.u[1];
+ (*ctx->block1)(scratch.c,scratch.c,ctx->key1);
+ scratch.u[0] ^= tweak.u[0];
+ scratch.u[1] ^= tweak.u[1];
+ memcpy(out-16,scratch.c,16);
+ }
+ else {
+ union { u64 u[2]; u8 c[16]; } tweak1;
+
+ if (is_endian.little) {
+ unsigned int carry,res;
+
+ res = 0x87&(((int)tweak.d[3])>>31);
+ carry = (unsigned int)(tweak.u[0]>>63);
+ tweak1.u[0] = (tweak.u[0]<<1)^res;
+ tweak1.u[1] = (tweak.u[1]<<1)|carry;
}
else {
- union { u64 u[2]; u8 c[16]; } tweak1;
-
- if (is_endian.little) {
- unsigned int carry,res;
-
- res = 0x87&(((int)tweak.d[3])>>31);
- carry = tweak.u[0]>>63;
- tweak1.u[0] = (tweak.u[0]<<1)^res;
- tweak1.u[1] = (tweak.u[1]<<1)|carry;
- }
- else {
- unsigned int carry,c;
-
- for (carry=0,i=0;i<16;++i) {
- c = tweak.c[i];
- tweak1.c[i] = (c<<1)|carry;
- carry = c>>7;
- }
- tweak1.c[0] ^= 0x87&(0-carry);
+ size_t c;
+
+ for (c=0,i=0;i<16;++i) {
+ /*+ substitutes for |, because c is 1 bit */
+ c += ((size_t)tweak.c[i])<<1;
+ tweak1.c[i] = (u8)c;
+ c = c>>8;
}
+ tweak1.c[0] ^= (u8)(0x87&(0-c));
+ }
#if defined(STRICT_ALIGNMENT)
- memcpy(scratch.c,inp,16);
- scratch.u[0] ^= tweak1.u[0];
- scratch.u[1] ^= tweak1.u[1];
+ memcpy(scratch.c,inp,16);
+ scratch.u[0] ^= tweak1.u[0];
+ scratch.u[1] ^= tweak1.u[1];
#else
- scratch.u[0] = ((u64*)inp)[0]^tweak1.u[0];
- scratch.u[1] = ((u64*)inp)[1]^tweak1.u[1];
+ scratch.u[0] = ((u64*)inp)[0]^tweak1.u[0];
+ scratch.u[1] = ((u64*)inp)[1]^tweak1.u[1];
#endif
- (*ctx->block1)(scratch.c,scratch.c,ctx->key1);
- scratch.u[0] ^= tweak1.u[0];
- scratch.u[1] ^= tweak1.u[1];
-
- for (i=0;i<len;++i) {
- u8 c = inp[16+i];
- out[16+i] = scratch.c[i];
- scratch.c[i] = c;
- }
- scratch.u[0] ^= tweak.u[0];
- scratch.u[1] ^= tweak.u[1];
- (*ctx->block1)(scratch.c,scratch.c,ctx->key1);
- scratch.u[0] ^= tweak.u[0];
- scratch.u[1] ^= tweak.u[1];
- memcpy (out,scratch.c,16);
+ (*ctx->block1)(scratch.c,scratch.c,ctx->key1);
+ scratch.u[0] ^= tweak1.u[0];
+ scratch.u[1] ^= tweak1.u[1];
+
+ for (i=0;i<len;++i) {
+ u8 c = inp[16+i];
+ out[16+i] = scratch.c[i];
+ scratch.c[i] = c;
}
+ scratch.u[0] ^= tweak.u[0];
+ scratch.u[1] ^= tweak.u[1];
+ (*ctx->block1)(scratch.c,scratch.c,ctx->key1);
+#if defined(STRICT_ALIGNMENT)
+ scratch.u[0] ^= tweak.u[0];
+ scratch.u[1] ^= tweak.u[1];
+ memcpy (out,scratch.c,16);
+#else
+ ((u64*)out)[0] = scratch.u[0]^tweak.u[0];
+ ((u64*)out)[1] = scratch.u[1]^tweak.u[1];
+#endif
}
return 0;
projects / oweals / openssl.git / blobdiff