From 3903ac6526e05088f2b9409990c058e2152b367b Mon Sep 17 00:00:00 2001
From: David Cernat <davidcernat@gmail.com>
Date: Sat, 21 Sep 2019 14:22:19 +0300
Subject: [PATCH] [Server] Add script functions for getting SHA256 hashes &
 random strings

---
 .../Script/Functions/Miscellaneous.cpp        | 29 +++++++++++++++++++
 .../Script/Functions/Miscellaneous.hpp        | 21 ++++++++++++++
 2 files changed, 50 insertions(+)

diff --git a/apps/openmw-mp/Script/Functions/Miscellaneous.cpp b/apps/openmw-mp/Script/Functions/Miscellaneous.cpp
index e81bc73c8..af6bed420 100644
--- a/apps/openmw-mp/Script/Functions/Miscellaneous.cpp
+++ b/apps/openmw-mp/Script/Functions/Miscellaneous.cpp
@@ -4,9 +4,38 @@
 
 #include <apps/openmw-mp/Networking.hpp>
 
+#include <extern/PicoSHA2/picosha2.h>
+
 #include <iostream>
+#include <random>
+
 using namespace std;
 
+const char *MiscellaneousFunctions::GenerateRandomString(unsigned int length) noexcept
+{
+    const std::string characters = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
+
+    std::random_device randomDevice;
+    std::mt19937 generator(randomDevice());
+    std::uniform_int_distribution<> distribution(0, characters.size() - 1);
+
+    std::string randomString;
+
+    for (std::size_t i = 0; i < length; ++i)
+    {
+        randomString += characters[distribution(generator)];
+    }
+
+    return randomString.c_str();
+}
+
+const char *MiscellaneousFunctions::GetSHA256Hash(const char* inputString) noexcept
+{
+    std::string hashString = picosha2::hash256_hex_string(std::string{inputString});
+
+    return hashString.c_str();
+}
+
 unsigned int MiscellaneousFunctions::GetLastPlayerId() noexcept
 {
     return Players::getLastPlayerId();
diff --git a/apps/openmw-mp/Script/Functions/Miscellaneous.hpp b/apps/openmw-mp/Script/Functions/Miscellaneous.hpp
index 96b646579..ae3bb843f 100644
--- a/apps/openmw-mp/Script/Functions/Miscellaneous.hpp
+++ b/apps/openmw-mp/Script/Functions/Miscellaneous.hpp
@@ -4,6 +4,10 @@
 #include "../Types.hpp"
 
 #define MISCELLANEOUSAPI \
+    {"GenerateRandomString",        MiscellaneousFunctions::GenerateRandomString},\
+    \
+    {"GetSHA256Hash",               MiscellaneousFunctions::GetSHA256Hash},\
+    \
     {"GetLastPlayerId",             MiscellaneousFunctions::GetLastPlayerId},\
     \
     {"GetCurrentMpNum",             MiscellaneousFunctions::GetCurrentMpNum},\
@@ -13,6 +17,23 @@ class MiscellaneousFunctions
 {
 public:
 
+    /**
+    * \brief Generate a random string of a particular length that only contains
+    *        letters and numbers.
+    *
+    * \param length The length of the generated string.
+    * \return The generated string.
+    */
+    static const char *GenerateRandomString(unsigned int length) noexcept;
+
+    /**
+    * \brief Get the SHA256 hash corresponding to an input string.
+    *
+    * \param inputString The input string.
+    * \return The SHA256 hash.
+    */
+    static const char *GetSHA256Hash(const char* inputString) noexcept;
+
     /**
     * \brief Get the last player ID currently connected to the server.
     *