LibTLS: Split TLSv12 to sensible categorical files

This commit splits the TLSv12 file into multiple files, and also removes
some magic values, to make the code less horrible. :^)

Libraries/LibTLS/ClientHandshake.cpp

@@ -0,0 +1,608 @@
+/*
+ * Copyright (c) 2020, Ali Mohammad Pur <ali.mpfard@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <LibCore/Timer.h>
+#include <LibCrypto/ASN1/DER.h>
+#include <LibCrypto/PK/Code/EMSA_PSS.h>
+#include <LibTLS/TLSv12.h>
+
+namespace TLS {
+
+ssize_t TLSv12::handle_server_hello_done(const ByteBuffer& buffer)
+{
+    if (buffer.size() < 3)
+        return (i8)Error::NeedMoreData;
+
+    size_t size = buffer[0] * 0x10000 + buffer[1] * 0x100 + buffer[2];
+
+    if (buffer.size() - 3 < size)
+        return (i8)Error::NeedMoreData;
+
+    return size + 3;
+}
+
+ssize_t TLSv12::handle_hello(const ByteBuffer& buffer, WritePacketStage& write_packets)
+{
+    write_packets = WritePacketStage::Initial;
+    if (m_context.connection_status != ConnectionStatus::Disconnected && m_context.connection_status != ConnectionStatus::Renegotiating) {
+        dbg() << "unexpected hello message";
+        return (i8)Error::UnexpectedMessage;
+    }
+    ssize_t res = 0;
+    size_t min_hello_size = 41;
+
+    if (min_hello_size > buffer.size()) {
+        dbg() << "need more data";
+        return (i8)Error::NeedMoreData;
+    }
+    size_t following_bytes = buffer[0] * 0x10000 + buffer[1] * 0x100 + buffer[2];
+    res += 3;
+    if (buffer.size() - res < following_bytes) {
+        dbg() << "not enough data after header: " << buffer.size() - res << " < " << following_bytes;
+        return (i8)Error::NeedMoreData;
+    }
+
+    if (buffer.size() - res < 2) {
+        dbg() << "not enough data for version";
+        return (i8)Error::NeedMoreData;
+    }
+    auto version = (Version)convert_between_host_and_network(*(const u16*)buffer.offset_pointer(res));
+
+    res += 2;
+    if (!supports_version(version))
+        return (i8)Error::NotSafe;
+
+    memcpy(m_context.remote_random, buffer.offset_pointer(res), sizeof(m_context.remote_random));
+    res += sizeof(m_context.remote_random);
+
+    u8 session_length = buffer[res++];
+    if (buffer.size() - res < session_length) {
+        dbg() << "not enough data for session id";
+        return (i8)Error::NeedMoreData;
+    }
+
+    if (session_length && session_length <= 32) {
+        memcpy(m_context.session_id, buffer.offset_pointer(res), session_length);
+        m_context.session_id_size = session_length;
+        dbg() << "Remote session ID:";
+        print_buffer(ByteBuffer::wrap(m_context.session_id, session_length));
+    } else {
+        m_context.session_id_size = 0;
+    }
+    res += session_length;
+
+    if (buffer.size() - res < 2) {
+        dbg() << "not enough data for cipher suite listing";
+        return (i8)Error::NeedMoreData;
+    }
+    auto cipher = (CipherSuite)convert_between_host_and_network(*(const u16*)buffer.offset_pointer(res));
+    res += 2;
+    if (!supports_cipher(cipher)) {
+        m_context.cipher = CipherSuite::Invalid;
+        dbg() << "No supported cipher could be agreed upon";
+        return (i8)Error::NoCommonCipher;
+    }
+    m_context.cipher = cipher;
+    dbg() << "Cipher: " << (u16)cipher;
+
+    // The handshake hash function is _always_ SHA256
+    m_context.handshake_hash.initialize(Crypto::Hash::HashKind::SHA256);
+
+    if (buffer.size() - res < 1) {
+        dbg() << "not enough data for compression spec";
+        return (i8)Error::NeedMoreData;
+    }
+    u8 compression = buffer[res++];
+    if (compression != 0) {
+        dbg() << "Server told us to compress, we will not!";
+        return (i8)Error::CompressionNotSupported;
+    }
+
+    if (res > 0) {
+        if (m_context.connection_status != ConnectionStatus::Renegotiating)
+            m_context.connection_status = ConnectionStatus::Negotiating;
+        if (m_context.is_server) {
+            dbg() << "unsupported: server mode";
+            write_packets = WritePacketStage::ServerHandshake;
+        }
+    }
+
+    if (res > 2) {
+        res += 2;
+    }
+
+    while ((ssize_t)buffer.size() - res >= 4) {
+        auto extension_type = (HandshakeExtension)convert_between_host_and_network(*(const u16*)buffer.offset_pointer(res));
+        res += 2;
+        u16 extension_length = convert_between_host_and_network(*(const u16*)buffer.offset_pointer(res));
+        res += 2;
+
+        dbg() << "extension " << (u16)extension_type << " with length " << extension_length;
+        if (extension_length) {
+            if (buffer.size() - res < extension_length) {
+                dbg() << "not enough data for extension";
+                return (i8)Error::NeedMoreData;
+            }
+
+            // SNI
+            if (extension_type == HandshakeExtension::ServerName) {
+                u16 sni_host_length = convert_between_host_and_network(*(const u16*)buffer.offset_pointer(res + 3));
+                if (buffer.size() - res - 5 < sni_host_length) {
+                    dbg() << "Not enough data for sni " << (buffer.size() - res - 5) << " < " << sni_host_length;
+                    return (i8)Error::NeedMoreData;
+                }
+
+                if (sni_host_length) {
+                    m_context.SNI = String { (const char*)buffer.offset_pointer(res + 5), sni_host_length };
+                    dbg() << "server name indicator: " << m_context.SNI;
+                }
+            } else if (extension_type == HandshakeExtension::ApplicationLayerProtocolNegotiation && m_context.alpn.size()) {
+                if (buffer.size() - res > 2) {
+                    auto alpn_length = convert_between_host_and_network(*(const u16*)buffer.offset_pointer(res));
+                    if (alpn_length && alpn_length <= extension_length - 2) {
+                        const u8* alpn = buffer.offset_pointer(res + 2);
+                        size_t alpn_position = 0;
+                        while (alpn_position < alpn_length) {
+                            u8 alpn_size = alpn[alpn_position++];
+                            if (alpn_size + alpn_position >= extension_length)
+                                break;
+                            String alpn_str { (const char*)alpn + alpn_position, alpn_length };
+                            if (alpn_size && m_context.alpn.contains_slow(alpn_str)) {
+                                m_context.negotiated_alpn = alpn_str;
+                                dbg() << "negotiated alpn: " << alpn_str;
+                                break;
+                            }
+                            alpn_position += alpn_length;
+                            if (!m_context.is_server) // server hello must contain one ALPN
+                                break;
+                        }
+                    }
+                }
+            } else if (extension_type == HandshakeExtension::SignatureAlgorithms) {
+                dbg() << "supported signatures: ";
+                print_buffer(buffer.slice_view(res, extension_length));
+                // FIXME: what are we supposed to do here?
+            }
+            res += extension_length;
+        }
+    }
+
+    return res;
+}
+
+ssize_t TLSv12::handle_finished(const ByteBuffer& buffer, WritePacketStage& write_packets)
+{
+    if (m_context.connection_status < ConnectionStatus::KeyExchange || m_context.connection_status == ConnectionStatus::Established) {
+        dbg() << "unexpected finished message";
+        return (i8)Error::UnexpectedMessage;
+    }
+
+    write_packets = WritePacketStage::Initial;
+
+    if (buffer.size() < 3) {
+        return (i8)Error::NeedMoreData;
+    }
+
+    size_t index = 3;
+
+    u32 size = buffer[0] * 0x10000 + buffer[1] * 0x100 + buffer[2];
+    index += 3;
+
+    if (size < 12) {
+        dbg() << "finished packet smaller than minimum size: " << size;
+        return (i8)Error::BrokenPacket;
+    }
+
+    if (size < buffer.size() - index) {
+        dbg() << "not enough data after length: " << size << " > " << buffer.size() - index;
+        return (i8)Error::NeedMoreData;
+    }
+
+    // TODO: Compare Hashes
+    dbg() << "FIXME: handle_finished :: Check message validity";
+    m_context.connection_status = ConnectionStatus::Established;
+
+    return handle_message(buffer);
+}
+
+void TLSv12::build_random(PacketBuilder& builder)
+{
+    u8 random_bytes[48];
+    size_t bytes = 48;
+
+    arc4random_buf(random_bytes, bytes);
+
+    // remove zeros from the random bytes
+    for (size_t i = 0; i < bytes; ++i)
+        if (!random_bytes[i])
+            random_bytes[i--] = arc4random();
+
+    if (m_context.is_server) {
+        dbg() << "Server mode not supported";
+        return;
+    } else {
+        *(u16*)random_bytes = convert_between_host_and_network((u16)Version::V12);
+    }
+
+    m_context.premaster_key = ByteBuffer::copy(random_bytes, bytes);
+
+    const auto& certificate = m_context.certificates[0];
+#ifdef TLS_DEBUG
+    dbg() << "PreMaster secret";
+    print_buffer(m_context.premaster_key);
+#endif
+
+    Crypto::PK::RSA_PKCS1_EME rsa(certificate.public_key.modulus(), 0, certificate.public_key.public_exponent());
+
+    u8 out[rsa.output_size()];
+    auto outbuf = ByteBuffer::wrap(out, rsa.output_size());
+    rsa.encrypt(m_context.premaster_key, outbuf);
+
+#ifdef TLS_DEBUG
+    dbg() << "Encrypted: ";
+    print_buffer(outbuf);
+#endif
+
+    if (!compute_master_secret(bytes)) {
+        dbg() << "oh noes we could not derive a master key :(";
+        return;
+    }
+
+    builder.append_u24(outbuf.size() + 2);
+    builder.append((u16)outbuf.size());
+    builder.append(outbuf);
+}
+
+ssize_t TLSv12::handle_payload(const ByteBuffer& vbuffer)
+{
+    if (m_context.connection_status == ConnectionStatus::Established) {
+        auto packet = build_alert(false, (u8)AlertDescription::NoRenegotiation);
+        write_packet(packet);
+        return 1;
+    }
+    auto buffer = vbuffer;
+    auto buffer_length = buffer.size();
+    auto original_length = buffer_length;
+    while (buffer_length >= 4 && !m_context.critical_error) {
+        ssize_t payload_res = 0;
+        if (buffer_length < 1)
+            return (i8)Error::NeedMoreData;
+        auto type = buffer[0];
+        auto write_packets { WritePacketStage::Initial };
+        size_t payload_size = buffer[1] * 0x10000 + buffer[2] * 0x100 + buffer[3] + 3;
+#ifdef TLS_DEBUG
+        dbg() << "payload size: " << payload_size << " buffer length: " << buffer_length;
+#endif
+        if (payload_size + 1 > buffer_length)
+            return (i8)Error::NeedMoreData;
+
+        switch (type) {
+        case HelloRequest:
+            if (m_context.handshake_messages[0] >= 1) {
+                dbg() << "unexpected hello request message";
+                payload_res = (i8)Error::UnexpectedMessage;
+                break;
+            }
+            ++m_context.handshake_messages[0];
+            dbg() << "hello request (renegotiation?)";
+            if (m_context.connection_status == ConnectionStatus::Established) {
+                // renegotiation
+                payload_res = (i8)Error::NoRenegotiation;
+            } else {
+                // :shrug:
+                payload_res = (i8)Error::UnexpectedMessage;
+            }
+            break;
+        case ClientHello:
+            // FIXME: We only support client mode right now
+            if (m_context.is_server) {
+                ASSERT_NOT_REACHED();
+            }
+            payload_res = (i8)Error::UnexpectedMessage;
+            break;
+        case ServerHello:
+            if (m_context.handshake_messages[2] >= 1) {
+                dbg() << "unexpected server hello message";
+                payload_res = (i8)Error::UnexpectedMessage;
+                break;
+            }
+            ++m_context.handshake_messages[2];
+#ifdef TLS_DEBUG
+            dbg() << "server hello";
+#endif
+            if (m_context.is_server) {
+                dbg() << "unsupported: server mode";
+                ASSERT_NOT_REACHED();
+            } else {
+                payload_res = handle_hello(buffer.slice_view(1, payload_size), write_packets);
+            }
+            break;
+        case HelloVerifyRequest:
+            dbg() << "unsupported: DTLS";
+            payload_res = (i8)Error::UnexpectedMessage;
+            break;
+        case CertificateMessage:
+            if (m_context.handshake_messages[4] >= 1) {
+                dbg() << "unexpected certificate message";
+                payload_res = (i8)Error::UnexpectedMessage;
+                break;
+            }
+            ++m_context.handshake_messages[4];
+#ifdef TLS_DEBUG
+            dbg() << "certificate";
+#endif
+            if (m_context.connection_status == ConnectionStatus::Negotiating) {
+                if (m_context.is_server) {
+                    dbg() << "unsupported: server mode";
+                    ASSERT_NOT_REACHED();
+                }
+                payload_res = handle_certificate(buffer.slice_view(1, payload_size));
+            } else {
+                payload_res = (i8)Error::UnexpectedMessage;
+            }
+            break;
+        case ServerKeyExchange:
+            if (m_context.handshake_messages[5] >= 1) {
+                dbg() << "unexpected server key exchange message";
+                payload_res = (i8)Error::UnexpectedMessage;
+                break;
+            }
+            ++m_context.handshake_messages[5];
+#ifdef TLS_DEBUG
+            dbg() << "server key exchange";
+#endif
+            if (m_context.is_server) {
+                dbg() << "unsupported: server mode";
+                ASSERT_NOT_REACHED();
+            } else {
+                payload_res = handle_server_key_exchange(buffer.slice_view(1, payload_size));
+            }
+            break;
+        case CertificateRequest:
+            if (m_context.handshake_messages[6] >= 1) {
+                dbg() << "unexpected certificate request message";
+                payload_res = (i8)Error::UnexpectedMessage;
+                break;
+            }
+            ++m_context.handshake_messages[6];
+            if (m_context.is_server) {
+                dbg() << "invalid request";
+                dbg() << "unsupported: server mode";
+                ASSERT_NOT_REACHED();
+            } else {
+                // we do not support "certificate request"
+                dbg() << "certificate request";
+                ASSERT_NOT_REACHED();
+            }
+            break;
+        case ServerHelloDone:
+            if (m_context.handshake_messages[7] >= 1) {
+                dbg() << "unexpected server hello done message";
+                payload_res = (i8)Error::UnexpectedMessage;
+                break;
+            }
+            ++m_context.handshake_messages[7];
+#ifdef TLS_DEBUG
+            dbg() << "server hello done";
+#endif
+            if (m_context.is_server) {
+                dbg() << "unsupported: server mode";
+                ASSERT_NOT_REACHED();
+            } else {
+                payload_res = handle_server_hello_done(buffer.slice_view(1, payload_size));
+                if (payload_res > 0)
+                    write_packets = WritePacketStage::ClientHandshake;
+            }
+            break;
+        case CertificateVerify:
+            if (m_context.handshake_messages[8] >= 1) {
+                dbg() << "unexpected certificate verify message";
+                payload_res = (i8)Error::UnexpectedMessage;
+                break;
+            }
+            ++m_context.handshake_messages[8];
+#ifdef TLS_DEBUG
+            dbg() << "certificate verify";
+#endif
+            if (m_context.connection_status == ConnectionStatus::KeyExchange) {
+                payload_res = handle_verify(buffer.slice_view(1, payload_size));
+            } else {
+                payload_res = (i8)Error::UnexpectedMessage;
+            }
+            break;
+        case ClientKeyExchange:
+            if (m_context.handshake_messages[9] >= 1) {
+                dbg() << "unexpected client key exchange message";
+                payload_res = (i8)Error::UnexpectedMessage;
+                break;
+            }
+            ++m_context.handshake_messages[9];
+#ifdef TLS_DEBUG
+            dbg() << "client key exchange";
+#endif
+            if (m_context.is_server) {
+                dbg() << "unsupported: server mode";
+                ASSERT_NOT_REACHED();
+            } else {
+                payload_res = (i8)Error::UnexpectedMessage;
+            }
+            break;
+        case Finished:
+            if (m_context.cached_handshake) {
+                m_context.cached_handshake.clear();
+            }
+            if (m_context.handshake_messages[10] >= 1) {
+                dbg() << "unexpected finished message";
+                payload_res = (i8)Error::UnexpectedMessage;
+                break;
+            }
+            ++m_context.handshake_messages[10];
+#ifdef TLS_DEBUG
+            dbg() << "finished";
+#endif
+            payload_res = handle_finished(buffer.slice_view(1, payload_size), write_packets);
+            if (payload_res > 0) {
+                memset(m_context.handshake_messages, 0, sizeof(m_context.handshake_messages));
+            }
+            break;
+        default:
+            dbg() << "message type not understood: " << type;
+            return (i8)Error::NotUnderstood;
+        }
+
+        if (type != HelloRequest) {
+            update_hash(buffer.slice_view(0, payload_size + 1));
+        }
+
+        // if something went wrong, send an alert about it
+        if (payload_res < 0) {
+            switch ((Error)payload_res) {
+            case Error::UnexpectedMessage: {
+                auto packet = build_alert(true, (u8)AlertDescription::UnexpectedMessage);
+                write_packet(packet);
+                break;
+            }
+            case Error::CompressionNotSupported: {
+                auto packet = build_alert(true, (u8)AlertDescription::DecompressionFailure);
+                write_packet(packet);
+                break;
+            }
+            case Error::BrokenPacket: {
+                auto packet = build_alert(true, (u8)AlertDescription::DecodeError);
+                write_packet(packet);
+                break;
+            }
+            case Error::NotVerified: {
+                auto packet = build_alert(true, (u8)AlertDescription::BadRecordMAC);
+                write_packet(packet);
+                break;
+            }
+            case Error::BadCertificate: {
+                auto packet = build_alert(true, (u8)AlertDescription::BadCertificate);
+                write_packet(packet);
+                break;
+            }
+            case Error::UnsupportedCertificate: {
+                auto packet = build_alert(true, (u8)AlertDescription::UnsupportedCertificate);
+                write_packet(packet);
+                break;
+            }
+            case Error::NoCommonCipher: {
+                auto packet = build_alert(true, (u8)AlertDescription::InsufficientSecurity);
+                write_packet(packet);
+                break;
+            }
+            case Error::NotUnderstood: {
+                auto packet = build_alert(true, (u8)AlertDescription::InternalError);
+                write_packet(packet);
+                break;
+            }
+            case Error::NoRenegotiation: {
+                auto packet = build_alert(true, (u8)AlertDescription::NoRenegotiation);
+                write_packet(packet);
+                break;
+            }
+            case Error::DecryptionFailed: {
+                auto packet = build_alert(true, (u8)AlertDescription::DecryptionFailed);
+                write_packet(packet);
+                break;
+            }
+            default:
+                dbg() << "Unknown TLS::Error with value " << payload_res;
+                ASSERT_NOT_REACHED();
+                break;
+            }
+            if (payload_res < 0)
+                return payload_res;
+        }
+        switch (write_packets) {
+        case WritePacketStage::Initial:
+            // nothing to write
+            break;
+        case WritePacketStage::ClientHandshake:
+            // Note: currently not used
+            if (m_context.client_verified == VerificationNeeded) {
+                auto packet = build_certificate();
+                write_packet(packet);
+                m_context.client_verified = Verified;
+            }
+            {
+#ifdef TLS_DEBUG
+                dbg() << "> Key exchange";
+#endif
+                auto packet = build_client_key_exchange();
+                write_packet(packet);
+            }
+            {
+#ifdef TLS_DEBUG
+                dbg() << "> change cipher spec";
+#endif
+                auto packet = build_change_cipher_spec();
+                write_packet(packet);
+            }
+            m_context.cipher_spec_set = 1;
+            m_context.local_sequence_number = 0;
+            {
+#ifdef TLS_DEBUG
+                dbg() << "> client finished";
+#endif
+                auto packet = build_finished();
+                write_packet(packet);
+            }
+            m_context.cipher_spec_set = 0;
+            break;
+        case WritePacketStage::ServerHandshake:
+            // server handshake
+            dbg() << "UNSUPPORTED: Server mode";
+            ASSERT_NOT_REACHED();
+            break;
+        case WritePacketStage::Finished:
+            // finished
+            {
+#ifdef TLS_DEBUG
+                dbg() << "> change cipher spec";
+#endif
+                auto packet = build_change_cipher_spec();
+                write_packet(packet);
+            }
+            {
+#ifdef TLS_DEBUG
+                dbg() << "> client finished";
+#endif
+                auto packet = build_finished();
+                write_packet(packet);
+            }
+            m_context.connection_status = ConnectionStatus::Established;
+            break;
+        }
+        payload_size++;
+        buffer_length -= payload_size;
+        buffer = buffer.slice(payload_size, buffer_length);
+    }
+    return original_length;
+}
+
+}

Libraries/LibTLS/Exchange.cpp

@@ -0,0 +1,216 @@
+/*
+ * Copyright (c) 2020, Ali Mohammad Pur <ali.mpfard@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <LibCore/Timer.h>
+#include <LibCrypto/ASN1/DER.h>
+#include <LibCrypto/PK/Code/EMSA_PSS.h>
+#include <LibTLS/TLSv12.h>
+
+namespace TLS {
+
+bool TLSv12::expand_key()
+{
+    u8 key[192]; // soooooooo many constants
+    auto key_buffer = ByteBuffer::wrap(key, 192);
+
+    if (m_context.master_key.size() == 0) {
+        dbg() << "expand_key() with empty master key";
+        return false;
+    }
+
+    auto key_size = key_length();
+    auto mac_size = mac_length();
+    auto iv_size = iv_length();
+
+    pseudorandom_function(
+        key_buffer,
+        m_context.master_key,
+        (const u8*)"key expansion", 13,
+        ByteBuffer::wrap(m_context.remote_random, 32),
+        ByteBuffer::wrap(m_context.local_random, 32));
+
+    size_t offset = 0;
+    memcpy(m_context.crypto.local_mac, key + offset, mac_size);
+    offset += mac_size;
+    memcpy(m_context.crypto.remote_mac, key + offset, mac_size);
+    offset += mac_size;
+
+    auto client_key = key + offset;
+    offset += key_size;
+    auto server_key = key + offset;
+    offset += key_size;
+    auto client_iv = key + offset;
+    offset += iv_size;
+    auto server_iv = key + offset;
+    offset += iv_size;
+
+#ifdef TLS_DEBUG
+    dbg() << "client key";
+    print_buffer(client_key, key_size);
+    dbg() << "server key";
+    print_buffer(server_key, key_size);
+    dbg() << "client iv";
+    print_buffer(client_iv, iv_size);
+    dbg() << "server iv";
+    print_buffer(server_iv, iv_size);
+    dbg() << "client mac key";
+    print_buffer(m_context.crypto.local_mac, mac_size);
+    dbg() << "server mac key";
+    print_buffer(m_context.crypto.remote_mac, mac_size);
+#endif
+
+    memcpy(m_context.crypto.local_iv, client_iv, iv_size);
+    memcpy(m_context.crypto.remote_iv, server_iv, iv_size);
+
+    m_aes_local = make<Crypto::Cipher::AESCipher::CBCMode>(ByteBuffer::wrap(client_key, key_size), key_size * 8, Crypto::Cipher::Intent::Encryption, Crypto::Cipher::PaddingMode::RFC5246);
+    m_aes_remote = make<Crypto::Cipher::AESCipher::CBCMode>(ByteBuffer::wrap(server_key, key_size), key_size * 8, Crypto::Cipher::Intent::Decryption, Crypto::Cipher::PaddingMode::RFC5246);
+
+    m_context.crypto.created = 1;
+
+    return true;
+}
+
+void TLSv12::pseudorandom_function(ByteBuffer& output, const ByteBuffer& secret, const u8* label, size_t label_length, const ByteBuffer& seed, const ByteBuffer& seed_b)
+{
+    if (!secret.size()) {
+        dbg() << "null secret";
+        return;
+    }
+
+    // RFC 5246: "In this section, we define one PRF, based on HMAC.  This PRF with the
+    //            SHA-256 hash function is used for all cipher suites defined in this
+    //            document and in TLS documents published prior to this document when
+    //            TLS 1.2 is negotiated."
+    // Apparently this PRF _always_ uses SHA256
+    Crypto::Authentication::HMAC<Crypto::Hash::SHA256> hmac(secret);
+
+    auto l_seed_size = label_length + seed.size() + seed_b.size();
+    u8 l_seed[l_seed_size];
+    auto label_seed_buffer = ByteBuffer::wrap(l_seed, l_seed_size);
+    label_seed_buffer.overwrite(0, label, label_length);
+    label_seed_buffer.overwrite(label_length, seed.data(), seed.size());
+    label_seed_buffer.overwrite(label_length + seed.size(), seed_b.data(), seed_b.size());
+
+    auto digest_size = hmac.digest_size();
+
+    u8 digest[digest_size];
+
+    auto digest_0 = ByteBuffer::wrap(digest, digest_size);
+
+    digest_0.overwrite(0, hmac.process(label_seed_buffer).immutable_data(), digest_size);
+
+    size_t index = 0;
+    while (index < output.size()) {
+        hmac.update(digest_0);
+        hmac.update(label_seed_buffer);
+        auto digest_1 = hmac.digest();
+
+        auto copy_size = min(digest_size, output.size() - index);
+
+        output.overwrite(index, digest_1.immutable_data(), copy_size);
+        index += copy_size;
+
+        digest_0.overwrite(0, hmac.process(digest_0).immutable_data(), digest_size);
+    }
+}
+
+bool TLSv12::compute_master_secret(size_t length)
+{
+    if (m_context.premaster_key.size() == 0 || length < 48) {
+        dbg() << "there's no way I can make a master secret like this";
+        dbg() << "I'd like to talk to your manager about this length of " << length;
+        return false;
+    }
+
+    m_context.master_key.clear();
+    m_context.master_key.grow(length);
+
+    pseudorandom_function(
+        m_context.master_key,
+        m_context.premaster_key,
+        (const u8*)"master secret", 13,
+        ByteBuffer::wrap(m_context.local_random, 32),
+        ByteBuffer::wrap(m_context.remote_random, 32));
+
+    m_context.premaster_key.clear();
+#ifdef TLS_DEBUG
+    dbg() << "master key:";
+    print_buffer(m_context.master_key);
+#endif
+    expand_key();
+    return true;
+}
+
+ByteBuffer TLSv12::build_certificate()
+{
+    dbg() << "FIXME: build_certificate";
+    return {};
+}
+
+ByteBuffer TLSv12::build_change_cipher_spec()
+{
+    PacketBuilder builder { MessageType::ChangeCipher, m_context.version, 64 };
+    builder.append((u8)1);
+    auto packet = builder.build();
+    update_packet(packet);
+    m_context.local_sequence_number = 0;
+    return packet;
+}
+
+ByteBuffer TLSv12::build_server_key_exchange()
+{
+    dbg() << "FIXME: build_server_key_exchange";
+    return {};
+}
+
+ByteBuffer TLSv12::build_client_key_exchange()
+{
+    PacketBuilder builder { MessageType::Handshake, m_context.version };
+    builder.append((u8)HandshakeType::ClientKeyExchange);
+    build_random(builder);
+
+    m_context.connection_status = ConnectionStatus::KeyExchange;
+
+    auto packet = builder.build();
+
+    update_packet(packet);
+
+    return packet;
+}
+
+ssize_t TLSv12::handle_server_key_exchange(const ByteBuffer&)
+{
+    dbg() << "FIXME: parse_server_key_exchange";
+    return 0;
+}
+
+ssize_t TLSv12::handle_verify(const ByteBuffer&)
+{
+    dbg() << "FIXME: parse_verify";
+    return 0;
+}
+
+}

Libraries/LibTLS/Handshake.cpp

@@ -0,0 +1,162 @@
+/*
+ * Copyright (c) 2020, Ali Mohammad Pur <ali.mpfard@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <LibCore/Timer.h>
+#include <LibCrypto/ASN1/DER.h>
+#include <LibCrypto/PK/Code/EMSA_PSS.h>
+#include <LibTLS/TLSv12.h>
+
+namespace TLS {
+
+ByteBuffer TLSv12::build_hello()
+{
+    arc4random_buf(&m_context.local_random, 32);
+
+    auto packet_version = (u16)m_context.version;
+    auto version = (u16)m_context.version;
+    PacketBuilder builder { MessageType::Handshake, packet_version };
+
+    builder.append((u8)ClientHello);
+
+    // hello length (for later)
+    u8 dummy[3];
+    builder.append(dummy, 3);
+
+    auto start_length = builder.length();
+
+    builder.append(version);
+    builder.append(m_context.local_random, sizeof(m_context.local_random));
+
+    builder.append(m_context.session_id_size);
+    if (m_context.session_id_size)
+        builder.append(m_context.session_id, m_context.session_id_size);
+
+    size_t extension_length = 0;
+    size_t alpn_length = 0;
+    size_t alpn_negotiated_length = 0;
+
+    // ALPN
+    if (!m_context.negotiated_alpn.is_null()) {
+        alpn_negotiated_length = m_context.negotiated_alpn.length();
+        alpn_length = alpn_negotiated_length + 1;
+        extension_length += alpn_length + 6;
+    } else if (m_context.alpn.size()) {
+        for (auto& alpn : m_context.alpn) {
+            size_t length = alpn.length();
+            alpn_length += length + 1;
+        }
+        if (alpn_length)
+            extension_length += alpn_length + 6;
+    }
+
+    // Ciphers
+    builder.append((u16)(4 * sizeof(u16)));
+    builder.append((u16)CipherSuite::RSA_WITH_AES_128_CBC_SHA256);
+    builder.append((u16)CipherSuite::RSA_WITH_AES_256_CBC_SHA256);
+    builder.append((u16)CipherSuite::RSA_WITH_AES_128_CBC_SHA);
+    builder.append((u16)CipherSuite::RSA_WITH_AES_256_CBC_SHA);
+
+    // we don't like compression
+    builder.append((u8)1);
+    builder.append((u8)0);
+
+    // set SNI if we have one
+    auto sni_length = 0;
+    if (!m_context.SNI.is_null())
+        sni_length = m_context.SNI.length();
+
+    if (sni_length)
+        extension_length += sni_length + 9;
+
+    builder.append((u16)extension_length);
+
+    if (sni_length) {
+        // SNI extension
+        builder.append((u16)HandshakeExtension::ServerName);
+        // extension length
+        builder.append((u16)(sni_length + 5));
+        // SNI length
+        builder.append((u16)(sni_length + 3));
+        // SNI type
+        builder.append((u8)0);
+        // SNI host length + value
+        builder.append((u16)sni_length);
+        builder.append((const u8*)m_context.SNI.characters(), sni_length);
+    }
+
+    if (alpn_length) {
+        // TODO
+        ASSERT_NOT_REACHED();
+    }
+
+    // set the "length" field of the packet
+    size_t remaining = builder.length() - start_length;
+    size_t payload_position = 6;
+    builder.set(payload_position, remaining / 0x10000);
+    remaining %= 0x10000;
+    builder.set(payload_position + 1, remaining / 0x100);
+    remaining %= 0x100;
+    builder.set(payload_position + 2, remaining);
+
+    auto packet = builder.build();
+    update_packet(packet);
+
+    return packet;
+}
+
+ByteBuffer TLSv12::build_alert(bool critical, u8 code)
+{
+    dbg() << "FIXME: build_alert";
+    (void)critical;
+    (void)code;
+    return {};
+}
+
+ByteBuffer TLSv12::build_finished()
+{
+    PacketBuilder builder { MessageType::Handshake, m_context.version, 12 + 64 };
+    builder.append((u8)HandshakeType::Finished);
+
+    u32 out_size = 12;
+
+    builder.append_u24(out_size);
+
+    u8 out[out_size];
+    auto outbuffer = ByteBuffer::wrap(out, out_size);
+    auto dummy = ByteBuffer::create_zeroed(0);
+
+    auto digest = m_context.handshake_hash.digest();
+    auto hashbuf = ByteBuffer::wrap(digest.immutable_data(), m_context.handshake_hash.digest_size());
+    pseudorandom_function(outbuffer, m_context.master_key, (const u8*)"client finished", 15, hashbuf, dummy);
+
+    builder.append(outbuffer);
+    auto packet = builder.build();
+    update_packet(packet);
+
+    return packet;
+}
+
+}

Libraries/LibTLS/Makefile

@@ -1,4 +1,9 @@
-LIBTLS_OBJS = TLSv12.o
+LIBTLS_OBJS = TLSv12.o \
+              ClientHandshake.o \
+              Exchange.o \
+              Handshake.o \
+              Record.o \
+              Socket.o 
 
 OBJS = $(LIBTLS_OBJS)
 

Libraries/LibTLS/Record.cpp

@@ -0,0 +1,316 @@
+/*
+ * Copyright (c) 2020, Ali Mohammad Pur <ali.mpfard@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <LibCore/Timer.h>
+#include <LibCrypto/ASN1/DER.h>
+#include <LibCrypto/PK/Code/EMSA_PSS.h>
+#include <LibTLS/TLSv12.h>
+
+namespace TLS {
+
+void TLSv12::write_packet(ByteBuffer& packet)
+{
+    m_context.tls_buffer.append(packet.data(), packet.size());
+}
+
+void TLSv12::update_packet(ByteBuffer& packet)
+{
+    u32 header_size = 5;
+    *(u16*)packet.offset_pointer(3) = convert_between_host_and_network((u16)(packet.size() - header_size));
+
+    if (packet[0] != (u8)MessageType::ChangeCipher) {
+        if (packet[0] == (u8)MessageType::Handshake && packet.size() > header_size) {
+            u8 handshake_type = packet[header_size];
+            if (handshake_type != HandshakeType::HelloRequest && handshake_type != HandshakeType::HelloVerifyRequest) {
+                update_hash(packet.slice_view(header_size, packet.size() - header_size));
+            }
+        }
+        if (m_context.cipher_spec_set && m_context.crypto.created) {
+            size_t length = packet.size() - header_size + mac_length();
+            auto block_size = m_aes_local->cipher().block_size();
+            // if length is a multiple of block size, pad it up again
+            // since it seems no one handles aligned unpadded blocks
+            size_t padding = 0;
+            if (length % block_size == 0) {
+                padding = block_size;
+                length += padding;
+            }
+            size_t mac_size = mac_length();
+
+            if (m_context.crypto.created == 1) {
+                // `buffer' will continue to be encrypted
+                auto buffer = ByteBuffer::create_zeroed(length);
+                size_t buffer_position = 0;
+                u16 aligned_length = length + block_size - length % block_size;
+                auto iv_size = iv_length();
+
+                // we need enough space for a header, iv_length bytes of IV and whatever the packet contains
+                auto ct = ByteBuffer::create_zeroed(aligned_length + header_size + iv_size);
+
+                // copy the header over
+                ct.overwrite(0, packet.data(), header_size - 2);
+
+                // copy the packet, sans the header
+                buffer.overwrite(buffer_position, packet.offset_pointer(header_size), packet.size() - header_size);
+                buffer_position += packet.size() - header_size;
+
+                // get the appropricate HMAC value for the entire packet
+                auto mac = hmac_message(packet, {}, mac_size, true);
+
+                // write the MAC
+                buffer.overwrite(buffer_position, mac.data(), mac.size());
+                buffer_position += mac.size();
+
+                // if there's some padding to be done (since a packet MUST always be padded)
+                // apply it manually
+                if (padding) {
+                    memset(buffer.offset_pointer(buffer_position), padding - 1, padding);
+                    buffer_position += padding;
+                }
+
+                // should be the same value, but the manual padding
+                // throws a wrench into our plans
+                buffer.trim(buffer_position);
+
+                // FIXME: REALLY Should be filled with random bytes
+                auto iv = ByteBuffer::create_zeroed(iv_size);
+
+                // write it into the ciphertext portion of the message
+                ct.overwrite(header_size, iv.data(), iv.size());
+                ct.trim(length + block_size - length % block_size + header_size + block_size - padding);
+
+                // get a block to encrypt into
+                auto view = ct.slice_view(header_size + iv_size, length + block_size - length % block_size + block_size - padding - iv_size);
+
+                // encrypt the message
+                m_aes_local->encrypt(buffer, view, iv);
+
+                // store the correct ciphertext length into the packet
+                u16 ct_length = (u16)ct.size() - header_size;
+                *(u16*)ct.offset_pointer(header_size - 2) = convert_between_host_and_network(ct_length);
+
+                // replace the packet with the ciphertext
+                packet = ct;
+            }
+        }
+    }
+    ++m_context.local_sequence_number;
+}
+
+void TLSv12::update_hash(const ByteBuffer& message)
+{
+    m_context.handshake_hash.update(message);
+}
+
+ByteBuffer TLSv12::hmac_message(const ByteBuffer& buf, const Optional<ByteBuffer> buf2, size_t mac_length, bool local)
+{
+    u64 sequence_number = convert_between_host_and_network(local ? m_context.local_sequence_number : m_context.remote_sequence_number);
+    ensure_hmac(mac_length, local);
+    auto& hmac = local ? *m_hmac_local : *m_hmac_remote;
+#ifdef TLS_DEBUG
+    dbg() << "========================= PACKET DATA ==========================";
+    print_buffer((const u8*)&sequence_number, sizeof(u64));
+    print_buffer(buf);
+    if (buf2.has_value())
+        print_buffer(buf2.value());
+    dbg() << "========================= PACKET DATA ==========================";
+#endif
+    hmac.update((const u8*)&sequence_number, sizeof(u64));
+    hmac.update(buf);
+    if (buf2.has_value() && buf2.value().size()) {
+        hmac.update(buf2.value());
+    }
+    auto digest = hmac.digest();
+    auto mac = ByteBuffer::copy(digest.immutable_data(), digest.data_length());
+#ifdef TLS_DEBUG
+    dbg() << "HMAC of the block for sequence number " << m_context.local_sequence_number;
+    print_buffer(mac);
+#endif
+    return mac;
+}
+
+ssize_t TLSv12::handle_message(const ByteBuffer& buffer)
+{
+    auto res { 5ll };
+    size_t header_size = res;
+    ssize_t payload_res = 0;
+
+#ifdef TLS_DEBUG
+    dbg() << "buffer size: " << buffer.size();
+#endif
+    if (buffer.size() < 5) {
+        return (i8)Error::NeedMoreData;
+    }
+
+    auto type = (MessageType)buffer[0];
+    size_t buffer_position { 1 };
+
+    // FIXME: Read the version and verify it
+#ifdef TLS_DEBUG
+    auto version = (Version) * (const u16*)buffer.offset_pointer(buffer_position);
+    dbg() << "type: " << (u8)type << " version: " << (u16)version;
+#endif
+    buffer_position += 2;
+
+    auto length = convert_between_host_and_network(*(const u16*)buffer.offset_pointer(buffer_position));
+#ifdef TLS_DEBUG
+    dbg() << "record length: " << length << " at offset: " << buffer_position;
+#endif
+    buffer_position += 2;
+
+    if (buffer_position + length > buffer.size()) {
+        dbg() << "record length more than what we have: " << buffer.size();
+        return (i8)Error::NeedMoreData;
+    }
+
+#ifdef TLS_DEBUG
+    dbg() << "message type: " << (u8)type << ", length: " << length;
+#endif
+    ByteBuffer plain = buffer.slice_view(buffer_position, buffer.size() - buffer_position);
+
+    if (m_context.cipher_spec_set && type != MessageType::ChangeCipher) {
+#ifdef TLS_DEBUG
+        dbg() << "Encrypted: ";
+        print_buffer(buffer.slice_view(header_size, length));
+#endif
+
+        ASSERT(m_aes_remote);
+        auto iv_size = iv_length();
+
+        auto decrypted = m_aes_remote->create_aligned_buffer(length - iv_size);
+        auto iv = buffer.slice_view(header_size, iv_size);
+
+        m_aes_remote->decrypt(buffer.slice_view(header_size + iv_size, length - iv_size), decrypted, iv);
+
+        length = decrypted.size();
+
+#ifdef TLS_DEBUG
+        dbg() << "Decrypted: ";
+        print_buffer(decrypted);
+#endif
+
+        auto mac_size = mac_length();
+        if (length < mac_size) {
+            dbg() << "broken packet";
+            auto packet = build_alert(true, (u8)AlertDescription::DecryptError);
+            write_packet(packet);
+            return (i8)Error::BrokenPacket;
+        }
+
+        const u8* message_hmac = decrypted.offset_pointer(length - mac_size);
+        u8 temp_buf[5];
+        memcpy(temp_buf, buffer.offset_pointer(0), 3);
+        *(u16*)(temp_buf + 3) = convert_between_host_and_network(length);
+        auto hmac = hmac_message(ByteBuffer::wrap(temp_buf, 5), decrypted, mac_size);
+        auto message_mac = ByteBuffer::wrap(message_hmac, mac_size);
+        if (hmac != message_mac) {
+            dbg() << "integrity check failed (mac length " << length << ")";
+            dbg() << "mac received:";
+            print_buffer(message_mac);
+            dbg() << "mac computed:";
+            print_buffer(hmac);
+            auto packet = build_alert(true, (u8)AlertDescription::BadRecordMAC);
+            write_packet(packet);
+
+            return (i8)Error::IntegrityCheckFailed;
+        }
+        plain = decrypted.slice(0, length - mac_size);
+    }
+    m_context.remote_sequence_number++;
+
+    switch (type) {
+    case MessageType::ApplicationData:
+        if (m_context.connection_status != ConnectionStatus::Established) {
+            dbg() << "unexpected application data";
+            payload_res = (i8)Error::UnexpectedMessage;
+            auto packet = build_alert(true, (u8)AlertDescription::UnexpectedMessage);
+            write_packet(packet);
+        } else {
+#ifdef TLS_DEBUG
+            dbg() << "application data message of size " << plain.size();
+#endif
+
+            m_context.application_buffer.append(plain.data(), plain.size());
+        }
+        break;
+    case MessageType::Handshake:
+#ifdef TLS_DEBUG
+        dbg() << "tls handshake message";
+#endif
+        payload_res = handle_payload(plain);
+        break;
+    case MessageType::ChangeCipher:
+        if (m_context.connection_status != ConnectionStatus::KeyExchange) {
+            dbg() << "unexpected change cipher message";
+            auto packet = build_alert(true, (u8)AlertDescription::UnexpectedMessage);
+            payload_res = (i8)Error::UnexpectedMessage;
+        } else {
+#ifdef TLS_DEBUG
+            dbg() << "change cipher spec message";
+#endif
+            m_context.cipher_spec_set = true;
+            m_context.remote_sequence_number = 0;
+        }
+        break;
+    case MessageType::Alert:
+        dbg() << "alert message of length " << length;
+        if (length >= 2) {
+            print_buffer(plain);
+            auto level = plain[0];
+            auto code = plain[1];
+            if (level == (u8)AlertLevel::Critical) {
+                dbg() << "We were alerted of a critical error: " << code;
+                m_context.critical_error = code;
+                res = (i8)Error::UnknownError;
+            } else {
+                dbg() << "Alert: " << code;
+            }
+            if (code == 0) {
+                // close notify
+                res += 2;
+                auto closure_alert = build_alert(true, (u8)AlertDescription::CloseNotify);
+                write_packet(closure_alert);
+                flush();
+                m_context.connection_finished = true;
+            }
+            m_context.error_code = (Error)code;
+        }
+        break;
+    default:
+        dbg() << "message not understood";
+        return (i8)Error::NotUnderstood;
+    }
+
+    if (payload_res < 0)
+        return payload_res;
+
+    if (res > 0)
+        return header_size + length;
+
+    return res;
+}
+
+}

Libraries/LibTLS/Socket.cpp

@@ -0,0 +1,212 @@
+/*
+ * Copyright (c) 2020, Ali Mohammad Pur <ali.mpfard@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <LibCore/Timer.h>
+#include <LibCrypto/ASN1/DER.h>
+#include <LibCrypto/PK/Code/EMSA_PSS.h>
+#include <LibTLS/TLSv12.h>
+
+namespace TLS {
+
+Optional<ByteBuffer> TLSv12::read()
+{
+    if (m_context.application_buffer.size()) {
+        auto buf = m_context.application_buffer.slice(0, m_context.application_buffer.size());
+        m_context.application_buffer.clear();
+        return buf;
+    }
+    return {};
+}
+
+ByteBuffer TLSv12::read(size_t max_size)
+{
+    if (m_context.application_buffer.size()) {
+        auto length = min(m_context.application_buffer.size(), max_size);
+        auto buf = m_context.application_buffer.slice(0, length);
+        m_context.application_buffer = m_context.application_buffer.slice(length, m_context.application_buffer.size() - length);
+        return buf;
+    }
+    return {};
+}
+
+ByteBuffer TLSv12::read_line(size_t max_size)
+{
+    if (!can_read_line())
+        return {};
+
+    auto* start = m_context.application_buffer.data();
+    auto* newline = (u8*)memchr(m_context.application_buffer.data(), '\n', m_context.application_buffer.size());
+    ASSERT(newline);
+
+    size_t offset = newline - start;
+
+    if (offset > max_size)
+        return {};
+
+    auto buffer = ByteBuffer::copy(start, offset);
+    m_context.application_buffer = m_context.application_buffer.slice(offset + 1, m_context.application_buffer.size() - offset - 1);
+
+    return buffer;
+}
+
+bool TLSv12::write(const ByteBuffer& buffer)
+{
+    if (m_context.connection_status != ConnectionStatus::Established) {
+        dbg() << "write request while not connected";
+        return false;
+    }
+
+    PacketBuilder builder { MessageType::ApplicationData, m_context.version, buffer.size() };
+    builder.append(buffer);
+    auto packet = builder.build();
+
+    update_packet(packet);
+    write_packet(packet);
+
+    return true;
+}
+
+bool TLSv12::connect(const String& hostname, int port)
+{
+    set_sni(hostname);
+    return Core::Socket::connect(hostname, port);
+}
+
+bool TLSv12::common_connect(const struct sockaddr* saddr, socklen_t length)
+{
+    if (m_context.critical_error)
+        return false;
+
+    if (Core::Socket::is_connected()) {
+        if (is_established()) {
+            ASSERT_NOT_REACHED();
+        } else {
+            Core::Socket::close(); // reuse?
+        }
+    }
+
+    auto packet = build_hello();
+    write_packet(packet);
+
+    Core::Socket::on_connected = [this] {
+        Core::Socket::on_ready_to_read = [this] {
+            if (!Core::Socket::is_open()) {
+                // an abrupt closure (the server is a jerk)
+                dbg() << "Socket not open, assuming abrupt closure";
+                m_context.connection_finished = true;
+            }
+            if (m_context.critical_error) {
+                dbg() << "READ CRITICAL ERROR " << m_context.critical_error << " :(";
+                if (on_tls_error)
+                    on_tls_error((AlertDescription)m_context.critical_error);
+                return;
+            }
+            if (m_context.application_buffer.size() == 0 && m_context.connection_finished) {
+                if (on_tls_finished)
+                    on_tls_finished();
+                if (m_context.tls_buffer.size()) {
+                    dbg() << "connection closed without finishing data transfer, " << m_context.tls_buffer.size() << " bytes still in buffer";
+                } else {
+                    m_context.connection_finished = false;
+                }
+                if (!m_context.application_buffer.size())
+                    m_context.connection_status = ConnectionStatus::Disconnected;
+                return;
+            }
+            flush();
+            consume(Core::Socket::read(4096)); // FIXME: how much is proper?
+            if (is_established() && m_context.application_buffer.size())
+                if (on_tls_ready_to_read)
+                    on_tls_ready_to_read(*this);
+        };
+        Core::Socket::on_ready_to_write = [this] {
+            if (!Core::Socket::is_open()) {
+                // an abrupt closure (the server is a jerk)
+                dbg() << "Socket not open, assuming abrupt closure";
+                m_context.connection_finished = true;
+            }
+            if (m_context.critical_error) {
+                dbg() << "WRITE CRITICAL ERROR " << m_context.critical_error << " :(";
+                if (on_tls_error)
+                    on_tls_error((AlertDescription)m_context.critical_error);
+                return;
+            }
+            if (m_context.connection_finished) {
+                if (on_tls_finished)
+                    on_tls_finished();
+                if (m_context.tls_buffer.size()) {
+                    dbg() << "connection closed without finishing data transfer, " << m_context.tls_buffer.size() << " bytes still in buffer";
+                } else {
+                    m_context.connection_finished = false;
+                    dbg() << "FINISHED";
+                }
+                if (!m_context.application_buffer.size()) {
+                    m_context.connection_status = ConnectionStatus::Disconnected;
+                    return;
+                }
+            }
+            flush();
+            if (is_established() && !m_context.application_buffer.size()) // hey client, you still have stuff to read...
+                if (on_tls_ready_to_write)
+                    on_tls_ready_to_write(*this);
+        };
+        if (on_tls_connected)
+            on_tls_connected();
+    };
+    bool success = Core::Socket::common_connect(saddr, length);
+    if (!success)
+        return false;
+
+    return true;
+}
+
+bool TLSv12::flush()
+{
+    auto out_buffer = write_buffer().data();
+    size_t out_buffer_index { 0 };
+    size_t out_buffer_length = write_buffer().size();
+
+    if (out_buffer_length == 0)
+        return true;
+
+#ifdef TLS_DEBUG
+    dbg() << "SENDING...";
+    print_buffer(out_buffer, out_buffer_length);
+#endif
+    if (Core::Socket::write(&out_buffer[out_buffer_index], out_buffer_length)) {
+        write_buffer().clear();
+        return true;
+    }
+    if (m_context.send_retries++ == 10) {
+        // drop the records, we can't send
+        dbg() << "Dropping " << write_buffer().size() << " bytes worth of TLS records as max retries has been reached";
+        write_buffer().clear();
+        m_context.send_retries = 0;
+    }
+    return false;
+}
+
+}

Libraries/LibTLS/TLSPacketBuilder.h

@@ -0,0 +1,118 @@
+/*
+ * Copyright (c) 2020, Ali Mohammad Pur <ali.mpfard@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+#include <AK/ByteBuffer.h>
+#include <AK/Types.h>
+
+namespace TLS {
+
+enum class MessageType : u8 {
+    ChangeCipher = 0x14,
+    Alert = 0x15,
+    Handshake = 0x16,
+    ApplicationData = 0x17,
+};
+
+enum class Version : u16 {
+    V10 = 0x0301,
+    V11 = 0x0302,
+    V12 = 0x0303,
+    V13 = 0x0304
+};
+
+class PacketBuilder {
+public:
+    PacketBuilder(MessageType type, u16 version, size_t size_hint = 0xfdf)
+        : PacketBuilder(type, (Version)version, size_hint)
+    {
+    }
+
+    PacketBuilder(MessageType type, Version version, size_t size_hint = 0xfdf)
+    {
+        m_packet_data = ByteBuffer::create_uninitialized(size_hint + 16);
+        m_current_length = 5;
+        m_packet_data[0] = (u8)type;
+        *(u16*)m_packet_data.offset_pointer(1) = convert_between_host_and_network((u16)version);
+    }
+
+    inline void append(u16 value)
+    {
+        value = convert_between_host_and_network(value);
+        append((const u8*)&value, sizeof(value));
+    }
+    inline void append(u8 value)
+    {
+        append((const u8*)&value, sizeof(value));
+    }
+    inline void append(const ByteBuffer& data)
+    {
+        append(data.data(), data.size());
+    }
+    inline void append_u24(u32 value)
+    {
+        u8 buf[3];
+        buf[0] = value / 0x10000;
+        value %= 0x10000;
+        buf[1] = value / 0x100;
+        value %= 0x100;
+        buf[2] = value;
+
+        append(buf, 3);
+    }
+    inline void append(const u8* data, size_t bytes)
+    {
+        if (bytes == 0)
+            return;
+
+        auto old_length = m_current_length;
+        m_current_length += bytes;
+
+        if (m_packet_data.size() < m_current_length) {
+            m_packet_data.grow(m_current_length);
+        }
+
+        m_packet_data.overwrite(old_length, data, bytes);
+    }
+    inline ByteBuffer build()
+    {
+        auto length = m_current_length;
+        m_current_length = 0;
+        return m_packet_data.slice(0, length);
+    }
+    inline void set(size_t offset, u8 value)
+    {
+        ASSERT(offset < m_current_length);
+        m_packet_data[offset] = value;
+    }
+    size_t length() const { return m_current_length; }
+
+private:
+    ByteBuffer m_packet_data;
+    size_t m_current_length;
+};
+}

Libraries/LibTLS/TLSv12.h

@@ -40,37 +40,22 @@
 
 namespace TLS {
 
+inline static void print_buffer(const ByteBuffer& buffer)
+{
+    for (size_t i { 0 }; i < buffer.size(); ++i)
+        dbgprintf("%02x ", buffer[i]);
+    dbgprintf("\n");
+}
+
+inline static void print_buffer(const u8* buffer, size_t size)
+{
+    for (size_t i { 0 }; i < size; ++i)
+        dbgprintf("%02x ", buffer[i]);
+    dbgprintf("\n");
+}
+
 class Socket;
 
-enum class KeyExchangeAlgorithms {
-    DHE_DSS,
-    DHE_RSA,
-    DH_Anon,
-    RSA,
-    DH_DSS,
-    DH_RSA,
-    EC_DiffieHellman
-};
-
-enum class ClientCertificateType {
-    RSA_Sign = 1,
-    DSS_Sign = 2,
-    RSA_FixedDH = 3,
-    DSS_FixedDH = 4,
-    RSA_EphemeralDH = 5,
-    DSS_EphemeralDH = 6,
-    ECDSA_Sign = 64,
-    RSA_FixedECDH = 65,
-    ECDSA_FixedECDH = 66
-};
-
-enum class SignatureAlgorithm {
-    Anonymous = 0,
-    RSA = 1,
-    DSA = 2,
-    ECDSA = 3
-};
-
 enum class CipherSuite {
     Invalid = 0,
     AES_128_GCM_SHA256 = 0x1301,
@@ -145,6 +130,46 @@ enum class AlertLevel : u8 {
     Critical = 0x02
 };
 
+enum HandshakeType {
+    HelloRequest = 0x00,
+    ClientHello = 0x01,
+    ServerHello = 0x02,
+    HelloVerifyRequest = 0x03,
+    CertificateMessage = 0x0b,
+    ServerKeyExchange = 0x0c,
+    CertificateRequest = 0x0d,
+    ServerHelloDone = 0x0e,
+    CertificateVerify = 0x0f,
+    ClientKeyExchange = 0x10,
+    Finished = 0x14
+};
+
+enum class HandshakeExtension : u16 {
+    ServerName = 0x00,
+    ApplicationLayerProtocolNegotiation = 0x10,
+    SignatureAlgorithms = 0x0d,
+};
+
+enum class WritePacketStage {
+    Initial = 0,
+    ClientHandshake = 1,
+    ServerHandshake = 2,
+    Finished = 3,
+};
+
+enum class ConnectionStatus {
+    Disconnected,
+    Negotiating,
+    KeyExchange,
+    Renegotiating,
+    Established,
+};
+
+enum ClientVerificationStaus {
+    Verified,
+    VerificationNeeded,
+};
+
 struct Certificate {
     u16 version;
     u32 algorithm;
@@ -183,7 +208,7 @@ struct Context {
 
     u8 remote_random[32];
     // To be predictable
-    u8 local_random[32] { 0 };
+    u8 local_random[32];
     u8 session_id[32];
     u8 session_id_size { 0 };
     CipherSuite cipher;
@@ -209,7 +234,7 @@ struct Context {
     u64 remote_sequence_number { 0 };
     u64 local_sequence_number { 0 };
 
-    u8 connection_status { 0 };
+    ConnectionStatus connection_status { ConnectionStatus::Disconnected };
     u8 critical_error { 0 };
     Error error_code { Error::NoError };
 
@@ -225,7 +250,7 @@ struct Context {
 
     ByteBuffer cached_handshake;
 
-    u8 client_verified { 0 };
+    ClientVerificationStaus client_verified { Verified };
 
     bool connection_finished { false };
 
@@ -236,6 +261,8 @@ struct Context {
 
     Vector<String> alpn;
     StringView negotiated_alpn;
+
+    size_t send_retries { 0 };
 };
 
 class TLSv12 : public Core::Socket {
@@ -258,19 +285,19 @@ public:
     }
 
     ByteBuffer& write_buffer() { return m_context.tls_buffer; }
-    bool established() const { return m_context.connection_status == 0xff; }
+    bool is_established() const { return m_context.connection_status == ConnectionStatus::Established; }
     virtual bool connect(const String&, int) override;
 
     void set_sni(const StringView& sni)
     {
-        if (m_context.is_server || m_context.critical_error || m_context.connection_status != 0) {
+        if (m_context.is_server || m_context.critical_error || m_context.connection_status != ConnectionStatus::Disconnected) {
             dbg() << "invalid state for set_sni";
             return;
         }
         m_context.SNI = sni;
     }
 
-    Optional<Certificate> parse_asn1(const ByteBuffer& buffer, bool client_cert = false);
+    Optional<Certificate> parse_asn1(const ByteBuffer& buffer, bool client_cert = false) const;
     bool load_certificates(const ByteBuffer& pem_buffer);
     bool load_private_key(const ByteBuffer& pem_buffer);
 
@@ -280,12 +307,12 @@ public:
     void add_alpn(const StringView& alpn);
     bool has_alpn(const StringView& alpn) const;
 
-    bool cipher_supported(CipherSuite suite) const
+    bool supports_cipher(CipherSuite suite) const
     {
         return suite == CipherSuite::RSA_WITH_AES_128_CBC_SHA256 || suite == CipherSuite::RSA_WITH_AES_256_CBC_SHA256 || suite == CipherSuite::RSA_WITH_AES_128_CBC_SHA || suite == CipherSuite::RSA_WITH_AES_256_CBC_SHA;
     }
 
-    bool version_supported(Version v) const
+    bool supports_version(Version v) const
     {
         return v == Version::V12;
     }
@@ -312,6 +339,7 @@ private:
     void consume(const ByteBuffer& record);
 
     ByteBuffer hmac_message(const ByteBuffer& buf, const Optional<ByteBuffer> buf2, size_t mac_length, bool local = false);
+    void ensure_hmac(size_t digest_size, bool local);
 
     void update_packet(ByteBuffer& packet);
     void update_hash(const ByteBuffer& in);
@@ -332,8 +360,8 @@ private:
 
     bool flush();
 
-    ssize_t handle_hello(const ByteBuffer& buffer, size_t&);
+    ssize_t handle_hello(const ByteBuffer& buffer, WritePacketStage&);
-    ssize_t handle_finished(const ByteBuffer& buffer, size_t&);
+    ssize_t handle_finished(const ByteBuffer& buffer, WritePacketStage&);
     ssize_t handle_certificate(const ByteBuffer& buffer);
     ssize_t handle_server_key_exchange(const ByteBuffer& buffer);
     ssize_t handle_server_hello_done(const ByteBuffer& buffer);
@@ -410,10 +438,12 @@ private:
     bool compute_master_secret(size_t length);
 
     Context m_context;
-    RefPtr<Core::Notifier> m_notifier;
 
-    OwnPtr<Crypto::Cipher::AESCipher::CBCMode> m_aes_local { nullptr };
+    OwnPtr<Crypto::Authentication::HMAC<Crypto::Hash::Manager>> m_hmac_local;
-    OwnPtr<Crypto::Cipher::AESCipher::CBCMode> m_aes_remote { nullptr };
+    OwnPtr<Crypto::Authentication::HMAC<Crypto::Hash::Manager>> m_hmac_remote;
+
+    OwnPtr<Crypto::Cipher::AESCipher::CBCMode> m_aes_local;
+    OwnPtr<Crypto::Cipher::AESCipher::CBCMode> m_aes_remote;
 };
 
 namespace Constants {
@@ -441,6 +471,5 @@ constexpr static const u8 TLS_RSA_SIGN_SHA256_OID[] { 0x2a, 0x86, 0x48, 0x86, 0x
 
 }
 
-namespace Utilities {
+using namespace Crypto;
-}
 }