Adding upstream version 2.7.6.upstream/2.7.6upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 167 insertions, 0 deletions

diff --git a/src/libdnssec/shared/hex.c b/src/libdnssec/shared/hex.c
new file mode 100644
index 0000000..03c1491
--- /dev/null
+++ b/src/libdnssec/shared/hex.c
@@ -0,0 +1,167 @@
+/*  Copyright (C) 2018 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <assert.h>
+#include <string.h>
+#include <stdbool.h>
+
+#include "libdnssec/binary.h"
+#include "libdnssec/error.h"
+
+#include "contrib/ctype.h"
+
+/* -- binary to hex -------------------------------------------------------- */
+
+static const char BIN_TO_HEX[] = { '0', '1', '2', '3', '4', '5', '6', '7',
+				   '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
+
+int bin_to_hex_static(const dnssec_binary_t *bin, dnssec_binary_t *hex)
+{
+	if (!bin || !hex) {
+		return DNSSEC_EINVAL;
+	}
+
+	if (bin->size * 2 != hex->size) {
+		return DNSSEC_EINVAL;
+	}
+
+	for (size_t i = 0; i < bin->size; i++) {
+		hex->data[2*i]   = BIN_TO_HEX[bin->data[i] >> 4];
+		hex->data[2*i+1] = BIN_TO_HEX[bin->data[i] & 0x0f];
+	}
+
+	return DNSSEC_EOK;
+}
+
+int bin_to_hex(const dnssec_binary_t *bin, char **hex_ptr)
+{
+	if (!bin || !hex_ptr) {
+		return DNSSEC_EINVAL;
+	}
+
+	size_t hex_size = bin->size * 2;
+	char *hex = malloc(hex_size + 1);
+	if (!hex) {
+		return DNSSEC_ENOMEM;
+	}
+
+	dnssec_binary_t hex_bin = { .data = (uint8_t *)hex, .size = hex_size };
+	bin_to_hex_static(bin, &hex_bin);
+	hex[hex_size] = '\0';
+
+	*hex_ptr = hex;
+
+	return DNSSEC_EOK;
+}
+
+/* -- hex to binary -------------------------------------------------------- */
+
+/*!
+ * Convert HEX character to numeric value (assumes valid and lowercase input).
+ */
+static uint8_t hex_to_number(const char hex)
+{
+	if (hex >= '0' && hex <= '9') {
+		return hex - '0';
+	} else if (hex >= 'a' && hex <= 'f') {
+		return hex - 'a' + 10;
+	} else {
+		assert(hex >= 'A' && hex <= 'F');
+		return hex - 'A' + 10;
+	}
+}
+
+/*!
+ * Check if the input string has valid size and contains valid characters.
+ */
+static bool hex_valid_input(const dnssec_binary_t *hex)
+{
+	assert(hex);
+
+	if (hex->size % 2 != 0) {
+		return false;
+	}
+
+	for (int i = 0; i < hex->size; i++) {
+		if (!is_xdigit(hex->data[i])) {
+			return false;
+		}
+	}
+
+	return true;
+}
+
+/*!
+ * Perform hex to bin conversion without checking the validity.
+ */
+static void hex_to_bin_convert(const dnssec_binary_t *hex, dnssec_binary_t *bin)
+{
+	assert(hex);
+	assert(bin);
+
+	for (size_t i = 0; i < bin->size; i++) {
+		uint8_t high = hex_to_number(hex->data[2 * i]);
+		uint8_t low  = hex_to_number(hex->data[2 * i + 1]);
+		bin->data[i] = high << 4 | low;
+	}
+}
+
+int hex_to_bin_static(const dnssec_binary_t *hex, dnssec_binary_t *bin)
+{
+	if (!hex || !bin) {
+		return DNSSEC_EINVAL;
+	}
+
+	if (hex->size / 2 != bin->size) {
+		return DNSSEC_EINVAL;
+	}
+
+	if (!hex_valid_input(hex)) {
+		return DNSSEC_MALFORMED_DATA;
+	}
+
+	hex_to_bin_convert(hex, bin);
+
+	return DNSSEC_EOK;
+}
+
+int hex_to_bin(const char *hex_str, dnssec_binary_t *bin)
+{
+	if (!hex_str || !bin) {
+		return DNSSEC_EINVAL;
+	}
+
+	dnssec_binary_t hex = { .data = (uint8_t *)hex_str, .size = strlen(hex_str) };
+	if (!hex_valid_input(&hex)) {
+		return DNSSEC_MALFORMED_DATA;
+	}
+
+	size_t bin_size = hex.size / 2;
+	if (bin_size == 0) {
+		bin->size = 0;
+		bin->data = NULL;
+		return DNSSEC_EOK;
+	}
+
+	int result = dnssec_binary_alloc(bin, bin_size);
+	if (result != DNSSEC_EOK) {
+		return result;
+	}
+
+	hex_to_bin_static(&hex, bin);
+
+	return DNSSEC_EOK;
+}