diff options
Diffstat (limited to 'crypto/xts.c')
| -rw-r--r-- | crypto/xts.c | 46 |
1 files changed, 26 insertions, 20 deletions
diff --git a/crypto/xts.c b/crypto/xts.c index 3c1a92f01d..bee23f890e 100644 --- a/crypto/xts.c +++ b/crypto/xts.c @@ -26,6 +26,12 @@ #include "qemu/osdep.h" #include "crypto/xts.h" +typedef union { + uint8_t b[XTS_BLOCK_SIZE]; + uint64_t u[2]; +} xts_uint128; + + static void xts_mult_x(uint8_t *I) { int x; @@ -85,7 +91,7 @@ void xts_decrypt(const void *datactx, uint8_t *dst, const uint8_t *src) { - uint8_t PP[XTS_BLOCK_SIZE], CC[XTS_BLOCK_SIZE], T[XTS_BLOCK_SIZE]; + xts_uint128 PP, CC, T; unsigned long i, m, mo, lim; /* get number of blocks */ @@ -102,10 +108,10 @@ void xts_decrypt(const void *datactx, } /* encrypt the iv */ - encfunc(tweakctx, XTS_BLOCK_SIZE, T, iv); + encfunc(tweakctx, XTS_BLOCK_SIZE, T.b, iv); for (i = 0; i < lim; i++) { - xts_tweak_encdec(datactx, decfunc, src, dst, T); + xts_tweak_encdec(datactx, decfunc, src, dst, T.b); src += XTS_BLOCK_SIZE; dst += XTS_BLOCK_SIZE; @@ -113,27 +119,27 @@ void xts_decrypt(const void *datactx, /* if length is not a multiple of XTS_BLOCK_SIZE then */ if (mo > 0) { - memcpy(CC, T, XTS_BLOCK_SIZE); - xts_mult_x(CC); + memcpy(&CC, &T, XTS_BLOCK_SIZE); + xts_mult_x(CC.b); /* PP = tweak decrypt block m-1 */ - xts_tweak_encdec(datactx, decfunc, src, PP, CC); + xts_tweak_encdec(datactx, decfunc, src, PP.b, CC.b); /* Pm = first length % XTS_BLOCK_SIZE bytes of PP */ for (i = 0; i < mo; i++) { - CC[i] = src[XTS_BLOCK_SIZE + i]; - dst[XTS_BLOCK_SIZE + i] = PP[i]; + CC.b[i] = src[XTS_BLOCK_SIZE + i]; + dst[XTS_BLOCK_SIZE + i] = PP.b[i]; } for (; i < XTS_BLOCK_SIZE; i++) { - CC[i] = PP[i]; + CC.b[i] = PP.b[i]; } /* Pm-1 = Tweak uncrypt CC */ - xts_tweak_encdec(datactx, decfunc, CC, dst, T); + xts_tweak_encdec(datactx, decfunc, CC.b, dst, T.b); } /* Decrypt the iv back */ - decfunc(tweakctx, XTS_BLOCK_SIZE, iv, T); + decfunc(tweakctx, XTS_BLOCK_SIZE, iv, T.b); } @@ -146,7 +152,7 @@ void xts_encrypt(const void *datactx, uint8_t *dst, const uint8_t *src) { - uint8_t PP[XTS_BLOCK_SIZE], CC[XTS_BLOCK_SIZE], T[XTS_BLOCK_SIZE]; + xts_uint128 PP, CC, T; unsigned long i, m, mo, lim; /* get number of blocks */ @@ -163,10 +169,10 @@ void xts_encrypt(const void *datactx, } /* encrypt the iv */ - encfunc(tweakctx, XTS_BLOCK_SIZE, T, iv); + encfunc(tweakctx, XTS_BLOCK_SIZE, T.b, iv); for (i = 0; i < lim; i++) { - xts_tweak_encdec(datactx, encfunc, src, dst, T); + xts_tweak_encdec(datactx, encfunc, src, dst, T.b); dst += XTS_BLOCK_SIZE; src += XTS_BLOCK_SIZE; @@ -175,22 +181,22 @@ void xts_encrypt(const void *datactx, /* if length is not a multiple of XTS_BLOCK_SIZE then */ if (mo > 0) { /* CC = tweak encrypt block m-1 */ - xts_tweak_encdec(datactx, encfunc, src, CC, T); + xts_tweak_encdec(datactx, encfunc, src, CC.b, T.b); /* Cm = first length % XTS_BLOCK_SIZE bytes of CC */ for (i = 0; i < mo; i++) { - PP[i] = src[XTS_BLOCK_SIZE + i]; - dst[XTS_BLOCK_SIZE + i] = CC[i]; + PP.b[i] = src[XTS_BLOCK_SIZE + i]; + dst[XTS_BLOCK_SIZE + i] = CC.b[i]; } for (; i < XTS_BLOCK_SIZE; i++) { - PP[i] = CC[i]; + PP.b[i] = CC.b[i]; } /* Cm-1 = Tweak encrypt PP */ - xts_tweak_encdec(datactx, encfunc, PP, dst, T); + xts_tweak_encdec(datactx, encfunc, PP.b, dst, T.b); } /* Decrypt the iv back */ - decfunc(tweakctx, XTS_BLOCK_SIZE, iv, T); + decfunc(tweakctx, XTS_BLOCK_SIZE, iv, T.b); } |