1 files changed, 43 insertions, 0 deletions

diff --git a/src/util/binascii.c b/src/util/binascii.c
new file mode 100644
index 0000000..ae3f1ff
--- /dev/null
+++ b/src/util/binascii.c
@@ -0,0 +1,43 @@
+/*
+ * ecgen, tool for generating Elliptic curve domain parameters
+ * Copyright (C) 2017 J08nY
+ */
+#include "binascii.h"
+#include "util/memory.h"
+
+size_t binascii_blen(GEN i) {
+	pari_sp ltop = avma;
+	size_t result = (size_t)glength(binary_2k_nv(i, 8));
+	avma = ltop;
+	return result;
+}
+
+char *binascii_itob(GEN i, endian_e endianity) {
+	pari_sp ltop = avma;
+	GEN digits = binary_2k_nv(i, 8);
+	if (endianity == ENDIAN_LITTLE) {
+		digits = vecsmall_reverse(digits);
+	}
+	long blen = glength(digits);
+	char *result = try_malloc((size_t)blen);
+	for (long j = 1; j <= blen; ++j) {
+		result[j - 1] = (char)gel(digits, j);
+	}
+
+	avma = ltop;
+	return result;
+}
+
+GEN binascii_btoi(const char *bytes, size_t len, endian_e endianity) {
+	pari_sp ltop = avma;
+	GEN result = gen_0;
+	for (size_t i = 0; i < len; ++i) {
+		size_t index = i;
+		if (endianity == ENDIAN_LITTLE) {
+			index = (len - 1) - i;
+		}
+		result = addis(result, bytes[index]);
+		if (i < len - 1) result = shifti(result, 8);
+	}
+	return gerepileupto(ltop, result);
+}