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-rw-r--r--libtommath/bn_mp_import.c73
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+#include <tommath_private.h>
+#ifdef BN_MP_IMPORT_C
+/* LibTomMath, multiple-precision integer library -- Tom St Denis
+ *
+ * LibTomMath is a library that provides multiple-precision
+ * integer arithmetic as well as number theoretic functionality.
+ *
+ * The library was designed directly after the MPI library by
+ * Michael Fromberger but has been written from scratch with
+ * additional optimizations in place.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
+ */
+
+/* based on gmp's mpz_import.
+ * see http://gmplib.org/manual/Integer-Import-and-Export.html
+ */
+int mp_import(mp_int* rop, size_t count, int order, size_t size,
+ int endian, size_t nails, const void* op) {
+ int result;
+ size_t odd_nails, nail_bytes, i, j;
+ unsigned char odd_nail_mask;
+
+ mp_zero(rop);
+
+ if (endian == 0) {
+ union {
+ unsigned int i;
+ char c[4];
+ } lint;
+ lint.i = 0x01020304;
+
+ endian = (lint.c[0] == 4) ? -1 : 1;
+ }
+
+ odd_nails = (nails % 8);
+ odd_nail_mask = 0xff;
+ for (i = 0; i < odd_nails; ++i) {
+ odd_nail_mask ^= (1 << (7 - i));
+ }
+ nail_bytes = nails / 8;
+
+ for (i = 0; i < count; ++i) {
+ for (j = 0; j < (size - nail_bytes); ++j) {
+ unsigned char byte = *(
+ (unsigned char*)op +
+ (((order == 1) ? i : ((count - 1) - i)) * size) +
+ ((endian == 1) ? (j + nail_bytes) : (((size - 1) - j) - nail_bytes))
+ );
+
+ if (
+ (result = mp_mul_2d(rop, ((j == 0) ? (8 - odd_nails) : 8), rop)) != MP_OKAY) {
+ return result;
+ }
+
+ rop->dp[0] |= (j == 0) ? (byte & odd_nail_mask) : byte;
+ rop->used += 1;
+ }
+ }
+
+ mp_clamp(rop);
+
+ return MP_OKAY;
+}
+
+#endif
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */