/* * XOR two pieces of memory, copying the result into a third, which * may precisely alias one of the input pair (but no guarantees if it * partially overlaps). */ #include "defs.h" #include "misc.h" void memxor(uint8_t *out, const uint8_t *in1, const uint8_t *in2, size_t size) { switch (size & 15) { case 0: while (size >= 16) { size -= 16; *out++ = *in1++ ^ *in2++; case 15: *out++ = *in1++ ^ *in2++; case 14: *out++ = *in1++ ^ *in2++; case 13: *out++ = *in1++ ^ *in2++; case 12: *out++ = *in1++ ^ *in2++; case 11: *out++ = *in1++ ^ *in2++; case 10: *out++ = *in1++ ^ *in2++; case 9: *out++ = *in1++ ^ *in2++; case 8: *out++ = *in1++ ^ *in2++; case 7: *out++ = *in1++ ^ *in2++; case 6: *out++ = *in1++ ^ *in2++; case 5: *out++ = *in1++ ^ *in2++; case 4: *out++ = *in1++ ^ *in2++; case 3: *out++ = *in1++ ^ *in2++; case 2: *out++ = *in1++ ^ *in2++; case 1: *out++ = *in1++ ^ *in2++; } } }