1 files changed, 73 insertions, 4 deletions

diff --git a/src/exhaustive/brainpool_rfc.c b/src/exhaustive/brainpool_rfc.c
index 7af6b29..b3c5e5e 100644
--- a/src/exhaustive/brainpool_rfc.c
+++ b/src/exhaustive/brainpool_rfc.c
@@ -4,19 +4,88 @@
  */
 
 #include "brainpool_rfc.h"
+#include "brainpool.h"
+#include "util/bits.h"
 
-GENERATOR(brainpool_rfc_gen_seed_random) {
-
-}
+#define brainpool_delegate(func)            \
+	int ret = func(curve, args, state);     \
+	if (ret != 1) {                         \
+		return ret;                         \
+	}                                       \
+	curve->seed->type = SEED_BRAINPOOL_RFC; \
+	return 1;
 
 GENERATOR(brainpool_rfc_gen_seed_argument) {
+	brainpool_delegate(brainpool_gen_seed_argument);
+}
 
+GENERATOR(brainpool_rfc_gen_seed_random) {
+	brainpool_delegate(brainpool_gen_seed_random);
 }
 
 GENERATOR(brainpool_rfc_gen_seed_input) {
-
+	brainpool_delegate(brainpool_gen_seed_input);
 }
 
 GENERATOR(brainpool_rfc_gen_equation) {
+	// field is definitely prime
+	pari_sp btop = avma;
+	seed_t *seed = curve->seed;
+	do {
+		if (seed->brainpool.update_seed) {
+			brainpool_update_seed(seed->seed);
+			seed->brainpool.update_seed = false;
+		}
+
+		GEN z;
+		bits_t *a_bits =
+		    brainpool_hash(seed->seed, seed->brainpool.w, seed->brainpool.v);
+		GEN a = bits_to_i(a_bits);
+		bits_free(&a_bits);
+		z = Fp_sqrtn(a, stoi(4), curve->field, NULL);
+		if (z == NULL) {
+			brainpool_update_seed(seed->seed);
+			avma = btop;
+			continue;
+		}
+		seed->brainpool.seed_a = bits_copy(seed->seed);
+
+		GEN b;
+		do {
+			brainpool_update_seed(seed->seed);
+			bits_t *b_bits = brainpool_hash(seed->seed, seed->brainpool.w,
+			                                seed->brainpool.v);
+			b = bits_to_i(b_bits);
+			bits_free(&b_bits);
+		} while (Fp_issquare(b, curve->field));
+
+		seed->brainpool.seed_b = bits_copy(seed->seed);
+
+		GEN mod_a = gmodulo(a, curve->field);
+		GEN mod_b = gmodulo(b, curve->field);
+
+		if (gequal0(gmulsg(-16, gadd(gmulsg(4, gpowgs(mod_a, 3)),
+		                             gmulsg(27, gsqr(mod_b)))))) {
+			brainpool_update_seed(seed->seed);
+			bits_free(&seed->brainpool.seed_a);
+			bits_free(&seed->brainpool.seed_b);
+			avma = btop;
+			continue;
+		}
+
+		brainpool_update_seed(seed->seed);
+		seed->brainpool.seed_bp = bits_copy(seed->seed);
+
+		bits_t *mult_bits =
+		    brainpool_hash(seed->seed, seed->brainpool.w, seed->brainpool.v);
+		seed->brainpool.mult = bits_to_i(mult_bits);
+
+		curve->a = mod_a;
+		curve->b = mod_b;
+		gerepileall(btop, 2, &curve->a, &curve->b);
+		break;
+	} while (true);
 
+	seed->brainpool.update_seed = true;
+	return 1;
 }
\ No newline at end of file