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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 00:53:35 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 00:53:35 +0000
commit69c6a41ffb878ef98c9378ed4b1634a404cfaa7f (patch)
treeb2a4f704565d62fbb129ab9dc3b35977c50e6e7f /src/libdnssec/shared/hex.c
parentInitial commit. (diff)
downloadknot-69c6a41ffb878ef98c9378ed4b1634a404cfaa7f.tar.xz
knot-69c6a41ffb878ef98c9378ed4b1634a404cfaa7f.zip
Adding upstream version 2.7.6.upstream/2.7.6upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/libdnssec/shared/hex.c')
-rw-r--r--src/libdnssec/shared/hex.c167
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;
+}