Crypt module (#549)

- Moved cryptography code out of Tactility project and into a kernel module.
- Converted C++ code to C style interface
- Hardened security

Modules/crypt-module/source/hash.cpp

@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <tactility/hash.h>
+
+uint32_t djb2_str(const char* str) {
+    uint32_t hash = 5381;
+    char c = (char)*str++;
+    while (c != 0) {
+        hash = ((hash << 5) + hash) + (uint32_t)c; // hash * 33 + c
+        c = (char)*str++;
+    }
+    return hash;
+}
+
+uint32_t djb2_data(const void* data, size_t length) {
+    uint32_t hash = 5381;
+    auto* data_bytes = static_cast<const uint8_t*>(data);
+    uint8_t c = *data_bytes++;
+    size_t index = 0;
+    while (index < length) {
+        hash = ((hash << 5) + hash) + (uint32_t)c; // hash * 33 + c
+        c = *data_bytes++;
+        index++;
+    }
+    return hash;
+}