diff --git a/src/chunkers/includes/Chunker.h b/src/chunkers/includes/Chunker.h
index 6e1e224..a203759 100644
--- a/src/chunkers/includes/Chunker.h
+++ b/src/chunkers/includes/Chunker.h
@@ -44,7 +44,7 @@ private:
 public:
     /// Returns the next chunk of the file
     /// Returns a single empty chunk if a file is empty
-    /// \return Pair consisting of chunk's bytes and its MD5 hash
+    /// \return Pair consisting of chunk's bytes and its SHA hash
     /// \throws Exception if EOF was already reached
     virtual std::pair<std::string, std::vector<char>> getNext() = 0;
 
diff --git a/src/chunkers/srcs/BuzhashChunker.cpp b/src/chunkers/srcs/BuzhashChunker.cpp
index 0b02f7e..84b8af5 100644
--- a/src/chunkers/srcs/BuzhashChunker.cpp
+++ b/src/chunkers/srcs/BuzhashChunker.cpp
@@ -4,7 +4,7 @@
 
 #include "../includes/BuzhashChunker.h"
 
-#include "../../crypto/includes/MD5.h"
+#include "../../crypto/includes/SHA.h"
 #include "../../utils/includes/Exception.h"
 
 BuzhashChunker::BuzhashChunker(std::streambuf *buf, unsigned long long minBytes, unsigned long long maxBytes, unsigned long long mask, uint32_t window) : Chunker(buf, maxBytes), window(window), minBytes(minBytes), mask(mask), buzhash(window) {}
@@ -18,7 +18,7 @@ std::pair<std::string, std::vector<char>> BuzhashChunker::getNext() {
     if (read != minBytes) {
         eof = true;
         rbuf.resize(read);
-        return {MD5::calculate(rbuf), rbuf};
+        return {SHA::calculate(rbuf), rbuf};
     }
 
     for (auto c: rbuf) {
@@ -38,5 +38,5 @@ std::pair<std::string, std::vector<char>> BuzhashChunker::getNext() {
         }
     }
 
-    return {MD5::calculate(rbuf), rbuf};
+    return {SHA::calculate(rbuf), rbuf};
 }
diff --git a/src/chunkers/srcs/ConstChunker.cpp b/src/chunkers/srcs/ConstChunker.cpp
index f41e1b5..bcfa515 100644
--- a/src/chunkers/srcs/ConstChunker.cpp
+++ b/src/chunkers/srcs/ConstChunker.cpp
@@ -4,7 +4,7 @@
 
 #include "../includes/ConstChunker.h"
 
-#include "../../crypto/includes/MD5.h"
+#include "../../crypto/includes/SHA.h"
 #include "../../utils/includes/Exception.h"
 
 ConstChunker::ConstChunker(std::streambuf *buf, unsigned long long maxBytes) : Chunker(buf, maxBytes) {}
@@ -21,7 +21,7 @@ std::pair<std::string, std::vector<char>> ConstChunker::getNext() {
         rbuf.resize(read);
     }
 
-    auto md5 = MD5::calculate(rbuf);
+    auto SHA = SHA::calculate(rbuf);
 
-    return {md5, rbuf};
+    return {SHA, rbuf};
 }
diff --git a/src/commands/includes/CommandsCommon.h b/src/commands/includes/CommandsCommon.h
index 8ff19ee..61cd259 100644
--- a/src/commands/includes/CommandsCommon.h
+++ b/src/commands/includes/CommandsCommon.h
@@ -18,7 +18,7 @@ namespace CommandsCommon {
     /// \param ignore       List of files to ignore
     /// \param spawner      Function to spawn other tasks
     /// \param processFile  Task to spawn on found files
-    void processDirWithIgnore(const std::filesystem::path &dir, std::vector<std::string> ignore, std::function<void(std::function<void()>)> spawner, std::function<void(std::filesystem::directory_entry)> processFile);
+    void processDirWithIgnore(const std::filesystem::path &dir, std::vector<std::string> ignore, const std::function<void(std::function<void()>)> &spawner, std::function<void(std::filesystem::directory_entry)> processFile);
 
     struct WorkerStats {
     public:
diff --git a/src/commands/srcs/CommandRun.cpp b/src/commands/srcs/CommandRun.cpp
index 6e9a0a3..64ce5f6 100644
--- a/src/commands/srcs/CommandRun.cpp
+++ b/src/commands/srcs/CommandRun.cpp
@@ -10,7 +10,7 @@
 
 #include "../../change_detectors/includes/ChangeDetectorFactory.h"
 #include "../../chunkers/includes/ChunkerFactory.h"
-#include "../../crypto/includes/MD5.h"
+#include "../../crypto/includes/SHA.h"
 #include "../../repo/includes/Serialize.h"
 #include "../../repo/includes/objects/Archive.h"
 #include "../../repo/includes/objects/Chunk.h"
@@ -187,8 +187,8 @@ Object::idType CommandRun::backupChunkFile(const std::filesystem::path &orig, co
     /// The order of checks is important, because is_directory follows the symlink
     if (std::filesystem::is_symlink(orig) || std::filesystem::is_directory(orig)) {
         auto contents = File::getFileContents(orig);
-        Chunk c(ctx.repo->getId(), MD5::calculate(contents), contents);
-        File f(ctx.repo->getId(), saveAs, c.length, File::getFileMtime(orig), c.md5, {c.id}, File::getFileType(orig));
+        Chunk c(ctx.repo->getId(), SHA::calculate(contents), contents);
+        File f(ctx.repo->getId(), saveAs, c.length, File::getFileMtime(orig), c.SHA, {c.id}, File::getFileType(orig));
         ctx.repo->putObject(c);
         ctx.repo->putObject(f);
         return f.id;
@@ -200,7 +200,7 @@ Object::idType CommandRun::backupChunkFile(const std::filesystem::path &orig, co
     if (!ifstream) throw Exception("Couldn't open " + orig.u8string() + " for reading");
     std::unique_ptr<Chunker> chunker = ChunkerFactory::getChunker(ctx.repo->getConfig(), ifstream.rdbuf());
 
-    MD5 fileHash;
+    SHA fileHash;
 
     std::vector<Object::idType> fileChunks;
     unsigned long long size = 0;
diff --git a/src/commands/srcs/CommandsCommon.cpp b/src/commands/srcs/CommandsCommon.cpp
index 1e14d74..af7b61d 100644
--- a/src/commands/srcs/CommandsCommon.cpp
+++ b/src/commands/srcs/CommandsCommon.cpp
@@ -23,7 +23,7 @@ bool CommandsCommon::isSubpath(const std::filesystem::path &prefix, const std::f
     return true;
 }
 
-void CommandsCommon::processDirWithIgnore(const std::filesystem::path &dir, std::vector<std::string> ignore, std::function<void(std::function<void()>)> spawner, std::function<void(std::filesystem::directory_entry)> processFile) {
+void CommandsCommon::processDirWithIgnore(const std::filesystem::path &dir, std::vector<std::string> ignore, const std::function<void(std::function<void()>)> &spawner, std::function<void(std::filesystem::directory_entry)> processFile) {
     if (!std::filesystem::is_directory(dir)) throw Exception(dir.u8string() + " is not a directory!");
 
     /// Don't process the directory if it has a ".nobackup" file
diff --git a/src/commands/srcs/Diff.cpp b/src/commands/srcs/Diff.cpp
index 9b07270..3da909c 100644
--- a/src/commands/srcs/Diff.cpp
+++ b/src/commands/srcs/Diff.cpp
@@ -74,20 +74,20 @@ std::string Diff::diffPercent(const ComparableFile &c1, const ComparableFile &c2
         /// Exit when asked to
         if (Signals::shouldQuit) throw Exception("Quitting");
         if (chunkp.second.empty()) continue;
-        std::string md5(chunkp.first.begin(), chunkp.first.end());
-        ch1hashes.emplace(md5);
-        hashsize[md5] = chunkp.second.size();
+        std::string SHA(chunkp.first.begin(), chunkp.first.end());
+        ch1hashes.emplace(SHA);
+        hashsize[SHA] = chunkp.second.size();
     }
 
     for (auto chunkp: ch2) {
         /// Exit when asked to
         if (Signals::shouldQuit) throw Exception("Quitting");
         if (chunkp.second.empty()) continue;
-        std::string md5(chunkp.first.begin(), chunkp.first.end());
-        hashsize[md5] = chunkp.second.size();
-        if (ch1hashes.count(md5) > 0) ch1hashes.erase(md5);
-        else if (ch1hashes.count(md5) == 0)
-            ch2diff.emplace(md5);
+        std::string SHA(chunkp.first.begin(), chunkp.first.end());
+        hashsize[SHA] = chunkp.second.size();
+        if (ch1hashes.count(SHA) > 0) ch1hashes.erase(SHA);
+        else if (ch1hashes.count(SHA) == 0)
+            ch2diff.emplace(SHA);
     }
 
     unsigned long long diff = 0;
diff --git a/src/crypto/CMakeLists.txt b/src/crypto/CMakeLists.txt
index 142f644..82fccb9 100644
--- a/src/crypto/CMakeLists.txt
+++ b/src/crypto/CMakeLists.txt
@@ -2,7 +2,7 @@ cmake_minimum_required(VERSION 3.22)
 
 find_package(OpenSSL REQUIRED)
 
-add_library(crypto srcs/AES.cpp srcs/CRC32.cpp srcs/MD5.cpp)
+add_library(crypto srcs/AES.cpp srcs/CRC32.cpp srcs/SHA.cpp)
 
 target_include_directories(crypto PUBLIC includes)
 
diff --git a/src/crypto/includes/MD5.h b/src/crypto/includes/SHA.h
similarity index 81%
rename from src/crypto/includes/MD5.h
rename to src/crypto/includes/SHA.h
index 87d6a9f..83c1188 100644
--- a/src/crypto/includes/MD5.h
+++ b/src/crypto/includes/SHA.h
@@ -2,8 +2,8 @@
 // Created by Stepan Usatiuk on 15.04.2023.
 //
 
-#ifndef SEMBACKUP_MD5_H
-#define SEMBACKUP_MD5_H
+#ifndef SEMBACKUP_SHA_H
+#define SEMBACKUP_SHA_H
 
 #include <array>
 #include <memory>
@@ -11,24 +11,24 @@
 
 #include <openssl/evp.h>
 
-/// Class to handle MD5 hashing
+/// Class to handle SHA hashing
 /**
  * Based on: https://wiki.openssl.org/index.php/EVP_Message_Digests
  */
-class MD5 {
+class SHA {
 public:
-    /// Constructs an empty MD5 hasher instance
+    /// Constructs an empty SHA hasher instance
     /// \throws     Exception on initialization error
-    MD5();
+    SHA();
 
     /// Calculates the hash for a given \p in char vector
     /// \param in   Constant reference to an input vector
-    /// \return     MD5 hash of \p in
+    /// \return     SHA hash of \p in
     static std::string calculate(const std::vector<char> &in);
 
     /// Calculates the hash for a given \p in string
     /// \param in   Constant reference to an input string
-    /// \return     MD5 hash of \p in
+    /// \return     SHA hash of \p in
     static std::string calculate(const std::string &in);
 
     /// Append a vector of chars to the current hash
@@ -45,4 +45,4 @@ private:
 };
 
 
-#endif//SEMBACKUP_MD5_H
+#endif//SEMBACKUP_SHA_H
diff --git a/src/crypto/srcs/MD5.cpp b/src/crypto/srcs/SHA.cpp
similarity index 69%
rename from src/crypto/srcs/MD5.cpp
rename to src/crypto/srcs/SHA.cpp
index 1c9b553..bd7743c 100644
--- a/src/crypto/srcs/MD5.cpp
+++ b/src/crypto/srcs/SHA.cpp
@@ -2,32 +2,32 @@
 // Created by Stepan Usatiuk on 15.04.2023.
 //
 
-#include "../includes/MD5.h"
+#include "../includes/SHA.h"
 
 #include "../../utils/includes/Exception.h"
 
-std::string MD5::calculate(const std::vector<char> &in) {
-    MD5 hasher;
+std::string SHA::calculate(const std::vector<char> &in) {
+    SHA hasher;
     hasher.feedData(in);
     return hasher.getHash();
 }
 
-MD5::MD5() {
+SHA::SHA() {
     if (!mdctx)
         throw Exception("Can't create hashing context!");
 
-    if (!EVP_DigestInit_ex(mdctx.get(), EVP_md5(), nullptr))
+    if (!EVP_DigestInit_ex(mdctx.get(), EVP_sha256(), nullptr))
         throw Exception("Can't create hashing context!");
 }
 
-void MD5::feedData(const std::vector<char> &in) {
+void SHA::feedData(const std::vector<char> &in) {
     if (in.empty()) return;
     if (!EVP_DigestUpdate(mdctx.get(), in.data(), in.size()))
         throw Exception("Error hashing!");
 }
 
-std::string MD5::getHash() {
-    std::array<char, 16> out;
+std::string SHA::getHash() {
+    std::array<char, 32> out;
     unsigned int s = 0;
 
     if (!EVP_DigestFinal_ex(mdctx.get(), reinterpret_cast<unsigned char *>(out.data()), &s))
@@ -42,7 +42,7 @@ std::string MD5::getHash() {
     return {out.begin(), out.end()};
 }
 
-std::string MD5::calculate(const std::string &in) {
+std::string SHA::calculate(const std::string &in) {
     std::vector<char> tmp(in.begin(), in.end());
-    return MD5::calculate(tmp);
+    return SHA::calculate(tmp);
 }
diff --git a/src/repo/includes/objects/Chunk.h b/src/repo/includes/objects/Chunk.h
index 87a4c99..79eb26e 100644
--- a/src/repo/includes/objects/Chunk.h
+++ b/src/repo/includes/objects/Chunk.h
@@ -21,10 +21,10 @@ public:
     /// \copydoc Object::serialize
     void serialize(std::vector<char> &out) const override;
 
-    /// Returns the MD5 of the chunk
+    /// Returns the SHA of the chunk
     std::string getKey() const override;
 
-    const std::string md5;          ///< MD5 hash of the chunk
+    const std::string SHA;          ///< SHA hash of the chunk
     const std::vector<char> data;   ///< Raw chunk data
     const unsigned long long length;///< Size of chunk in bytes
 };
diff --git a/src/repo/includes/objects/File.h b/src/repo/includes/objects/File.h
index e57b119..6107b5e 100644
--- a/src/repo/includes/objects/File.h
+++ b/src/repo/includes/objects/File.h
@@ -26,7 +26,7 @@ public:
 
     static inline const std::unordered_map<Type, std::string> TypeToStr{{Type::Normal, "normal"}, {Type::Symlink, "symlink"}, {Type::Directory, "directory"}};
 
-    File(Object::idType id, std::string name, unsigned long long bytes, unsigned long long mtime, std::string md5, std::vector<idType> chunks, Type fileType);
+    File(Object::idType id, std::string name, unsigned long long bytes, unsigned long long mtime, std::string SHA, std::vector<idType> chunks, Type fileType);
 
     /// Deserialization constructor
     File(std::vector<char>::const_iterator &in, const std::vector<char>::const_iterator &end);
@@ -64,7 +64,7 @@ public:
     const std::string name;        ///< Relative path to backup root, as UTF-8 string
     const unsigned long long bytes;///< Amount of bytes in the file
     const unsigned long long mtime;///< Last modification time as timestamp
-    const std::string md5;         ///< Hash of the file
+    const std::string SHA;         ///< Hash of the file
     const Type fileType;           ///< File type
 
     /// List of the chunks in file
diff --git a/src/repo/srcs/objects/Chunk.cpp b/src/repo/srcs/objects/Chunk.cpp
index 550cb61..ff4ddcd 100644
--- a/src/repo/srcs/objects/Chunk.cpp
+++ b/src/repo/srcs/objects/Chunk.cpp
@@ -7,11 +7,11 @@
 #include "../../../utils/includes/Exception.h"
 #include "../../includes/Serialize.h"
 
-Chunk::Chunk(idType id, std::string md5, std::vector<char> data) : Object(id, ObjectType::Chunk), data(std::move(data)), md5(std::move(md5)), length(this->data.size()) {}
+Chunk::Chunk(idType id, std::string SHA, std::vector<char> data) : Object(id, ObjectType::Chunk), data(std::move(data)), SHA(std::move(SHA)), length(this->data.size()) {}
 
 Chunk::Chunk(std::vector<char>::const_iterator &in, const std::vector<char>::const_iterator &end)
     : Object(in, end),
-      md5(Serialize::deserialize<std::remove_const<decltype(md5)>::type>(in, end)),
+      SHA(Serialize::deserialize<std::remove_const<decltype(SHA)>::type>(in, end)),
       data(Serialize::deserialize<std::remove_const<decltype(data)>::type>(in, end)),
       length(Serialize::deserialize<std::remove_const<decltype(length)>::type>(in, end)) {
     if (type != ObjectType::Chunk) throw Exception("Type mismatch for Chunk!");
@@ -20,11 +20,11 @@ Chunk::Chunk(std::vector<char>::const_iterator &in, const std::vector<char>::con
 
 void Chunk::serialize(std::vector<char> &out) const {
     Object::serialize(out);
-    Serialize::serialize(md5, out);
+    Serialize::serialize(SHA, out);
     Serialize::serialize(data, out);
     Serialize::serialize(length, out);
 }
 
 std::string Chunk::getKey() const {
-    return md5;
+    return SHA;
 }
diff --git a/src/repo/srcs/objects/File.cpp b/src/repo/srcs/objects/File.cpp
index 6725b3b..f77ca1c 100644
--- a/src/repo/srcs/objects/File.cpp
+++ b/src/repo/srcs/objects/File.cpp
@@ -11,15 +11,15 @@
 #include "../../../utils/includes/Exception.h"
 #include "../../includes/Serialize.h"
 
-File::File(Object::idType id, std::string name, unsigned long long bytes, unsigned long long mtime, std::string md5, std::vector<idType> chunks, Type fileType)
-    : Object(id, ObjectType::File), name(name), bytes(bytes), mtime(mtime), md5(md5), fileType(fileType), chunks(chunks) {}
+File::File(Object::idType id, std::string name, unsigned long long bytes, unsigned long long mtime, std::string SHA, std::vector<idType> chunks, Type fileType)
+    : Object(id, ObjectType::File), name(name), bytes(bytes), mtime(mtime), SHA(SHA), fileType(fileType), chunks(chunks) {}
 
 File::File(std::vector<char>::const_iterator &in, const std::vector<char>::const_iterator &end)
     : Object(in, end),
       name(Serialize::deserialize<std::string>(in, end)),
       bytes(Serialize::deserialize<unsigned long long>(in, end)),
       mtime(Serialize::deserialize<unsigned long long>(in, end)),
-      md5(Serialize::deserialize<std::remove_const<decltype(md5)>::type>(in, end)),
+      SHA(Serialize::deserialize<std::remove_const<decltype(SHA)>::type>(in, end)),
       fileType(Serialize::deserialize<std::remove_const<decltype(fileType)>::type>(in, end)),
       chunks(Serialize::deserialize<std::remove_const<decltype(chunks)>::type>(in, end)) {
     if (type != ObjectType::File) throw Exception("Type mismatch for File!");
@@ -30,7 +30,7 @@ void File::serialize(std::vector<char> &out) const {
     Serialize::serialize(name, out);
     Serialize::serialize(bytes, out);
     Serialize::serialize(mtime, out);
-    Serialize::serialize(md5, out);
+    Serialize::serialize(SHA, out);
     Serialize::serialize(fileType, out);
     Serialize::serialize(chunks, out);
 }
diff --git a/tests/crypto/srcs/CryptoTests.cpp b/tests/crypto/srcs/CryptoTests.cpp
index 33089e6..4873169 100644
--- a/tests/crypto/srcs/CryptoTests.cpp
+++ b/tests/crypto/srcs/CryptoTests.cpp
@@ -3,7 +3,7 @@
 //
 
 #include "AES.h"
-#include "MD5.h"
+#include "SHA.h"
 
 #include <gtest/gtest.h>
 
@@ -12,6 +12,11 @@ TEST(CryptoTests, AES) {
     auto enc = AES::encrypt(std::vector<char>(in.begin(), in.end()), "p1", "e");
     auto dec = AES::decrypt(enc, "p1", "e");
     EXPECT_EQ(in, std::string(dec.begin(), dec.end()));
+    
+    in = "";
+    enc = AES::encrypt(std::vector<char>(in.begin(), in.end()), "p1", "e");
+    dec = AES::decrypt(enc, "p1", "e");
+    EXPECT_EQ(in, std::string(dec.begin(), dec.end()));
 
     in = "1234567890asdfg";
     enc = AES::encrypt(std::vector<char>(in.begin(), in.end()), "p1", "e");
@@ -34,13 +39,13 @@ TEST(CryptoTests, AES) {
     EXPECT_EQ(in, std::string(dec.begin(), dec.end()));
 }
 
-TEST(CryptoTests, MD5) {
+TEST(CryptoTests, SHA) {
     std::vector<char> data{'h', 'e', 'l', 'l', 'o'};
-    std::array<unsigned char, 16> excepted{0x5d, 0x41, 0x40, 0x2a, 0xbc, 0x4b, 0x2a, 0x76, 0xb9, 0x71, 0x9d, 0x91, 0x10, 0x17, 0xc5, 0x92};
+    std::array<unsigned char, 32> excepted{0x2c, 0xf2, 0x4d, 0xba, 0x5f, 0xb0, 0xa3, 0x0e, 0x26, 0xe8, 0x3b, 0x2a, 0xc5, 0xb9, 0xe2, 0x9e, 0x1b, 0x16, 0x1e, 0x5c, 0x1f, 0xa7, 0x42, 0x5e, 0x73, 0x04, 0x33, 0x62, 0x93, 0x8b, 0x98, 0x24};
 
-    auto out = MD5::calculate(data);
+    auto out = SHA::calculate(data);
 
-    EXPECT_EQ(out.size(), 16);
+    EXPECT_EQ(out.size(), 32);
     for (int i = 0; i < out.size(); i++) {
         EXPECT_EQ(static_cast<uint8_t>(out[i]), excepted[i]);
     }
diff --git a/tests/repo/srcs/ChunkTest.cpp b/tests/repo/srcs/ChunkTest.cpp
index 6e598d5..25d711c 100644
--- a/tests/repo/srcs/ChunkTest.cpp
+++ b/tests/repo/srcs/ChunkTest.cpp
@@ -43,11 +43,11 @@ TEST(Chunk, Deserialize) {
             EXPECT_EQ(o2.data[i], o2e.data[i]);
         }
 
-        for (int i = 0; i < o1.md5.size(); i++) {
-            EXPECT_EQ(o1.md5[i], o1e.md5[i]);
+        for (int i = 0; i < o1.SHA.size(); i++) {
+            EXPECT_EQ(o1.SHA[i], o1e.SHA[i]);
         }
-        for (int i = 0; i < o2.md5.size(); i++) {
-            EXPECT_EQ(o2.md5[i], o2e.md5[i]);
+        for (int i = 0; i < o2.SHA.size(); i++) {
+            EXPECT_EQ(o2.SHA[i], o2e.SHA[i]);
         }
     }
 }