Flatten the Curve 448 source structure

[openssl.git] / crypto / ec / curve448 / arch_32 / f_impl.h

diff --git a/crypto/ec/curve448/arch_32/f_impl.h b/crypto/ec/curve448/arch_32/f_impl.h
new file mode 100644 (file)
index 0000000..c368788
--- /dev/null
+++ b/crypto/ec/curve448/arch_32/f_impl.h
@@ -0,0 +1,40 @@
+/* Copyright (c) 2014-2016 Cryptography Research, Inc.
+ * Released under the MIT License.  See LICENSE.txt for license information.
+ */
+
+#define GF_HEADROOM 2
+#define LIMB(x) (x##ull)&((1ull<<28)-1), (x##ull)>>28
+#define FIELD_LITERAL(a,b,c,d,e,f,g,h) \
+    {{LIMB(a),LIMB(b),LIMB(c),LIMB(d),LIMB(e),LIMB(f),LIMB(g),LIMB(h)}}
+    
+#define LIMB_PLACE_VALUE(i) 28
+
+void gf_add_RAW (gf out, const gf a, const gf b) {
+    for (unsigned int i=0; i<sizeof(*out)/sizeof(out->limb[0]); i++) {
+        out->limb[i] = a->limb[i] + b->limb[i];
+    }
+}
+
+void gf_sub_RAW (gf out, const gf a, const gf b) {
+    for (unsigned int i=0; i<sizeof(*out)/sizeof(out->limb[0]); i++) {
+        out->limb[i] = a->limb[i] - b->limb[i];
+    }
+}
+
+void gf_bias (gf a, int amt) {    
+    uint32_t co1 = ((1ull<<28)-1)*amt, co2 = co1-amt;
+    for (unsigned int i=0; i<sizeof(*a)/sizeof(a->limb[0]); i++) {
+        a->limb[i] += (i==sizeof(*a)/sizeof(a->limb[0])/2) ? co2 : co1;
+    }
+}
+
+void gf_weak_reduce (gf a) {
+    uint32_t mask = (1ull<<28) - 1;
+    uint32_t tmp = a->limb[15] >> 28;
+    a->limb[8] += tmp;
+    for (unsigned int i=15; i>0; i--) {
+        a->limb[i] = (a->limb[i] & mask) + (a->limb[i-1]>>28);
+    }
+    a->limb[0] = (a->limb[0] & mask) + tmp;
+}
+