From 3baeb11a8fbcfcdbc31976d421f17b85503b3ecd Mon Sep 17 00:00:00 2001
From: WuKong <rebirthmonkey@gmail.com>
Date: Fri, 4 Sep 2015 09:25:34 +0200
Subject: init attribute-based encryption

Change-Id: Iba1a3d722110abf747a0fba366f3ebc911d25b25
---
 moon-abe/pbc-0.5.14/ecc/mpc.c | 122 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 122 insertions(+)
 create mode 100644 moon-abe/pbc-0.5.14/ecc/mpc.c

(limited to 'moon-abe/pbc-0.5.14/ecc/mpc.c')

diff --git a/moon-abe/pbc-0.5.14/ecc/mpc.c b/moon-abe/pbc-0.5.14/ecc/mpc.c
new file mode 100644
index 00000000..e5341f99
--- /dev/null
+++ b/moon-abe/pbc-0.5.14/ecc/mpc.c
@@ -0,0 +1,122 @@
+//GMP based complex floats
+#include <stdio.h>
+#include <gmp.h>
+#include "mpc.h"
+
+//(a+bi)(c+di) = ac - bd  + ((a+b)(c+d) - ac - bd)i
+void mpc_mul(mpc_t res, mpc_t z0, mpc_t z1)
+{
+    mpf_t ac, bd, f0;
+    mpf_init(ac);
+    mpf_init(bd);
+    mpf_init(f0);
+    mpf_mul(ac, z0->a, z1->a);
+    mpf_mul(bd, z0->b, z1->b);
+    mpf_add(f0, z0->a, z0->b);
+    mpf_add(res->b, z1->a, z1->b);
+    mpf_mul(res->b, res->b, f0);
+    mpf_sub(res->b, res->b, ac);
+    mpf_sub(res->b, res->b, bd);
+    mpf_sub(res->a, ac, bd);
+    mpf_clear(f0);
+    mpf_clear(ac);
+    mpf_clear(bd);
+}
+
+void mpc_mul_2exp(mpc_t res, mpc_t z, unsigned long int e)
+{
+    mpf_mul_2exp(res->a, z->a, e);
+    mpf_mul_2exp(res->b, z->b, e);
+}
+
+//(a+bi)^2 = (a-b)(a+b) + 2abi
+void mpc_sqr(mpc_t res, mpc_t z)
+{
+    mpf_t f0, f1;
+    mpf_init(f0);
+    mpf_init(f1);
+    mpf_add(f0, z->a, z->b);
+    mpf_sub(f1, z->a, z->b);
+    mpf_mul(f0, f0, f1);
+    mpf_mul(f1, z->a, z->b);
+    mpf_set(res->a, f0);
+    mpf_add(res->b, f1, f1);
+    mpf_clear(f0);
+    mpf_clear(f1);
+}
+
+//1/(a+bi) = (1/(a^2 + b^2))(a-bi)
+//naive. TODO: use one that is less prone to (over/under)flows/precision loss
+void mpc_inv(mpc_t res, mpc_t z)
+{
+    mpf_t f0, f1;
+    mpf_init(f0);
+    mpf_init(f1);
+    mpf_mul(f0, z->a, z->a);
+    mpf_mul(f1, z->b, z->b);
+    mpf_add(f0, f0, f1);
+    mpf_ui_div(f0, 1, f0);
+    mpf_mul(res->a, z->a, f0);
+    mpf_neg(f0, f0);
+    mpf_mul(res->b, z->b, f0);
+    mpf_clear(f0);
+    mpf_clear(f1);
+}
+
+void mpc_div(mpc_t res, mpc_t z0, mpc_t z1)
+{
+    mpc_t c0;
+    mpc_init(c0);
+    mpc_inv(c0, z1);
+    mpc_mul(res, z0, c0);
+    mpc_clear(c0);
+}
+
+size_t mpc_out_str(FILE *stream, int base, size_t n_digits, mpc_t op)
+{
+    size_t result, status;
+    result = mpf_out_str(stream, base, n_digits, op->a);
+    if (!result) return 0;
+    if (mpf_sgn(op->b) >= 0) {
+        if (EOF == fputc('+', stream)) return 0;
+        result++;
+    }
+    status = mpf_out_str(stream, base, n_digits, op->b);
+    if (!status) return 0;
+    if (EOF == fputc('i', stream)) return 0;
+    return result + status + 1;
+}
+
+void mpc_pow_ui(mpc_t res, mpc_t z, unsigned int n)
+{
+    unsigned int m;
+    mpc_t z0;
+    mpc_init(z0);
+
+    //set m to biggest power of 2 less than n
+    for (m = 1; m <= n; m <<= 1);
+    m >>= 1;
+
+    mpf_set_ui(z0->a, 1);
+    mpf_set_ui(z0->b, 0);
+    while (m) {
+        mpc_mul(z0, z0, z0);
+        if (m & n) {
+            mpc_mul(z0, z0, z);
+        }
+        m >>= 1;
+    }
+    mpc_set(res, z0);
+    mpc_clear(z0);
+}
+
+void mpc_muli(mpc_t res, mpc_t z)
+{
+    //i(a+bi) = -b + ai
+    mpf_t f0;
+    mpf_init(f0);
+    mpf_neg(f0, z->b);
+    mpf_set(res->b, z->a);
+    mpf_set(res->a, f0);
+    mpf_clear(f0);
+}
-- 
cgit 1.2.3-korg