From 3d22b8de8bead66531843f1a5649e196068ac192 Mon Sep 17 00:00:00 2001
From: surtur <a_mirre@utb.cz>
Date: Sat, 8 Jan 2022 07:06:31 +0100
Subject: [PATCH] generator: fix memmove UB warnings

---
 generator.cpp | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/generator.cpp b/generator.cpp
index 0eefeb2..de51f1b 100644
--- a/generator.cpp
+++ b/generator.cpp
@@ -51,7 +51,7 @@ auto Generator::reseed(const std::string& s) -> void {
 	try {
 		std::lock_guard<std::mutex> lg(mtx);
 		std::string a{fortuna::Util::do_sha(da_key + s)};
-		std::memmove(&G.k[0], &a[0], G.k.SizeInBytes());
+		std::memmove(G.k, a.c_str(), G.k_length);
 		++G.ctr;
 		fmt::print("[i] generator: reseeded\n");
 	} catch(std::exception& e) {
@@ -77,13 +77,11 @@ auto Generator::do_crypto() -> std::string {
 	std::string plain{"Oh, I am fortune's fool!"};
 	std::string cipher, encoded_c;
 	// in case we need to convert counter to string
-	// std::string str_ctr{reinterpret_cast<const char*>(&G.k[0]), G.k.size()};
-	// std::string str_ctr{(G.ctr)};
+	std::string str_ctr{reinterpret_cast<const char*>(&G.ctr)};
 	// 16 bytes --> 128bit
 	static constexpr const std::size_t ctr_length{16};
 	CryptoPP::FixedSizeSecBlock<CryptoPP::byte, ctr_length> ctr;
-	// FIXME: potential (pretty-much) UB
-	std::memmove(&ctr, &G.ctr, ctr_length);
+	std::memmove(ctr, str_ctr.c_str(), ctr_length);
 
 	try {
 		CTR_Mode<Serpent>::Encryption e;
@@ -173,7 +171,7 @@ auto Generator::generate_random_data(uint n) -> std::string {
 
 		/* clear out the old key and set a new one */
 		std::memset(G.k, 0x00, G.k.size());
-		std::memmove(&G.k[0], &dst[0], dst.size());
+		std::memmove(G.k, dst.c_str(), G.k_length);
 	} catch(std::exception& e) {
 		fmt::print("{}", e.what());
 	}