Seed CRC with a session ID to prevent session cross-talk.

Author: Mysticial

Common/CRC32/pabb_CRC32_AVR8.h

@@ -20,11 +20,11 @@ extern const PROGMEM uint32_t PABB_CRC32_TABLE8[];
 
 void pabb_crc32_buffer(uint32_t* crc, const void* data, uint8_t length);
 
-static inline void pabb_crc32_write_to_message(void* data, size_t full_message_length){
+static inline void pabb_crc32_write_to_message(uint32_t seed, void* data, size_t full_message_length){
     char* ptr = (char*)data;
     size_t length_before_crc = full_message_length - sizeof(uint32_t);
     uint32_t* crc = (uint32_t*)(ptr + length_before_crc);
-    *crc = 0xffffffff;
+    *crc = seed;
     pabb_crc32_buffer(crc, ptr, length_before_crc);
 }
 

Common/CRC32/pabb_CRC32_Basic.h

@@ -20,10 +20,9 @@ extern const uint32_t PABB_CRC32_TABLE8[];
 
 void pabb_crc32_buffer(uint32_t* crc, const void* data, uint8_t length);
 
-static inline void pabb_crc32_write_to_message(void* data, size_t full_message_length){
+static inline void pabb_crc32_write_to_message(uint32_t crc, void* data, size_t full_message_length){
     char* ptr = (char*)data;
     size_t length_before_crc = full_message_length - sizeof(uint32_t);
-    uint32_t crc = 0xffffffff;
     pabb_crc32_buffer(&crc, ptr, length_before_crc);
     memcpy(ptr + length_before_crc, &crc, sizeof(uint32_t));
 }

Common/CRC32/pabb_CRC32_x86_SSE4.1.h

@@ -26,10 +26,9 @@ static inline void pabb_crc32_buffer(uint32_t* crc, const void* data, size_t len
     *crc = tmp;
 }
 
-static inline void pabb_crc32_write_to_message(void* data, size_t full_message_length){
+static inline void pabb_crc32_write_to_message(uint32_t crc, void* data, size_t full_message_length){
     char* ptr = (char*)data;
     size_t length_before_crc = full_message_length - sizeof(uint32_t);
-    uint32_t crc = 0xffffffff;
     pabb_crc32_buffer(&crc, ptr, length_before_crc);
     memcpy(ptr + length_before_crc, &crc, sizeof(uint32_t));
 }

Common/PABotBase2/PABotBase2_MessageProtocol.h

@@ -23,7 +23,7 @@ namespace PABotBase2{
 
 
 
-#define PABB2_MESSAGE_PROTOCOL_VERSION      2026041105
+#define PABB2_MESSAGE_PROTOCOL_VERSION      2026041106
 
 
 struct PABB_PACK MessageHeader{

Common/PABotBase2/ReliableConnectionLayer/PABotBase2CC_ReliableStreamConnection.cpp

@@ -8,6 +8,7 @@
 #include "Common/Cpp/PrettyPrint.h"
 //#include "Common/Cpp/Exceptions.h"
 #include "Common/PABotBase2/PABotBase2CC_MessageDumper.h"
+#include "CommonTools/Random.h"
 //#include "PABotBase2_ConnectionDebug.h"
 #include "PABotBase2CC_ReliableStreamConnection.h"
 
@@ -32,7 +33,7 @@ ReliableStreamConnection::ReliableStreamConnection(
     , m_unreliable_connection(unreliable_connection)
     , m_retransmit_timeout(retransmit_timeout)
     , m_print_lock(print_lock)
-    , m_reliable_sender(*this, 20)
+    , m_reliable_sender(*this, 24, random_u32())
     , m_log_everything(log_everything)
 //    , m_version_verified(false)
     , m_remote_protocol_compatible(false)
@@ -123,7 +124,11 @@ void ReliableStreamConnection::on_recv(const void* data, size_t bytes){
         cout << "ReliableStreamConnection::on_recv(): " << bytes << endl;
     }
 #endif
-    m_parser.push_bytes(*this, (const uint8_t*)data, bytes);
+    m_parser.push_bytes(
+        *this,
+        m_reliable_sender.session_id(),
+        (const uint8_t*)data, bytes
+    );
 }
 
 
@@ -168,11 +173,11 @@ size_t ReliableStreamConnection::unreliable_send(const void* data, size_t bytes)
 bool ReliableStreamConnection::reset(WallDuration timeout){
     {
         std::lock_guard<Mutex> lg(m_lock);
-        m_reliable_sender.reset();
+        m_reliable_sender.reset(m_reliable_sender.session_id() + 1);
         m_parser.reset();
         m_stream_coalescer.reset();
         throw_if_cancelled();
-        m_reliable_sender.send_packet(PABB2_CONNECTION_OPCODE_ASK_RESET, 0, nullptr);
+        m_reliable_sender.send_reset();
     }
     m_cv.notify_all();
     return wait_for_pending(timeout);
@@ -217,7 +222,7 @@ void ReliableStreamConnection::send_ack(uint8_t seqnum, uint8_t opcode){
     packet.header.seqnum = seqnum;
     packet.header.packet_bytes = sizeof(packet);
     packet.header.opcode = opcode;
-    pabb_crc32_write_to_message(&packet, sizeof(packet));
+    pabb_crc32_write_to_message(m_reliable_sender.session_id(), &packet, sizeof(packet));
     unreliable_send(&packet, sizeof(packet));
 }
 void ReliableStreamConnection::send_ack_u16(uint8_t seqnum, uint8_t opcode, uint16_t data){
@@ -231,7 +236,7 @@ void ReliableStreamConnection::send_ack_u16(uint8_t seqnum, uint8_t opcode, uint
     packet.header.packet_bytes = sizeof(packet);
     packet.header.opcode = opcode;
     packet.header.data = data;
-    pabb_crc32_write_to_message(&packet, sizeof(packet));
+    pabb_crc32_write_to_message(m_reliable_sender.session_id(), &packet, sizeof(packet));
     unreliable_send(&packet, sizeof(packet));
 }
 
@@ -376,6 +381,7 @@ void ReliableStreamConnection::on_packet(const PacketHeader* packet){
     case PABB2_CONNECTION_OPCODE_INFO_LABEL_H32:
     case PABB2_CONNECTION_OPCODE_INFO_LABEL_U32:
     case PABB2_CONNECTION_OPCODE_INFO_LABEL_I32:
+//    case PABB2_CONNECTION_OPCODE_WRONG_SESSION:
 //        cout << "Received ack" << endl;
         if (!m_log_everything){
             m_logger.log("[RSC]: Receive: (0x" + tostr_hex(packet->opcode) + ") " + tostr(packet), COLOR_PURPLE);

Common/PABotBase2/ReliableConnectionLayer/PABotBase2FW_ReliableStreamConnection.cpp

@@ -113,7 +113,11 @@ bool ReliableStreamConnectionFW::run_recv_events(const WallDuration& timeout){
         ? POLL_RATE
         : timeout;
 
-    const PacketHeader* header = m_parser.pull_bytes(m_unreliable_connection, adjusted_timeout);
+    const PacketHeader* header = m_parser.pull_bytes(
+        m_unreliable_connection,
+        m_reliable_sender.session_id(),
+        adjusted_timeout
+    );
     if (header == nullptr){
         return false;
     }
@@ -149,22 +153,33 @@ bool ReliableStreamConnectionFW::run_recv_events(const WallDuration& timeout){
 
     //  Now handle the different opcodes.
     uint8_t opcode = header->opcode & PABB2_CONNECTION_OPCODE_MASK;
+
     switch (opcode){
-    case PABB2_CONNECTION_OPCODE_ASK_RESET:
+    case PABB2_CONNECTION_OPCODE_ASK_RESET:{
+        if (header->packet_bytes < sizeof(PacketHeader_u32)){
+            return true;
+        }
+
+        const PacketHeader_u32* packet = (const PacketHeader_u32*)header;
+
+#ifdef PABB2_SUPPORTS_PRINTF_LOGGING
+        printf("Resetting to session ID: %zx\n", (size_t)packet->data);
+#endif
         m_stream_ready = false;
         m_send_is_currently_full = false;
-        m_reliable_sender.reset();
+        m_reliable_sender.reset(packet->data);
         m_parser.reset();
         m_stream_coalescer.reset();
         m_stream_coalescer.push_packet(0);
+#ifdef PABB2_ENABLE
+        issue_reset_to_all();
+#endif
         m_reliable_sender.send_oob_packet_empty(
             header->seqnum,
             PABB2_CONNECTION_OPCODE_RET_RESET
         );
-#ifdef PABB2_ENABLE
-        issue_reset_to_all();
-#endif
         return true;
+    }
     case PABB2_CONNECTION_OPCODE_ASK_VERSION:
         m_stream_coalescer.push_packet(header->seqnum);
         m_reliable_sender.send_oob_packet_u32(

Common/PABotBase2/ReliableConnectionLayer/PABotBase2_PacketParser.cpp

@@ -25,6 +25,7 @@ namespace PABotBase2{
 
 const PacketHeader* PacketParser::pull_bytes(
     UnreliableStreamConnectionPolling& connection,
+    const uint32_t& session_id,
     WallDuration timeout
 ){
     const uint8_t MIN_PACKET_SIZE = sizeof(PacketHeader) + sizeof(uint32_t);
@@ -114,7 +115,9 @@ const PacketHeader* PacketParser::pull_bytes(
 
     //  Verify the CRC.
 
-    uint32_t actual_crc = 0xffffffff;
+    uint32_t actual_crc = header->opcode == PABB2_CONNECTION_OPCODE_ASK_RESET
+        ? 0xffffffff
+        : session_id;
     pabb_crc32_buffer(&actual_crc, m_buffer, packet_bytes - sizeof(uint32_t));
 
     uint32_t expected_crc;
@@ -137,6 +140,7 @@ const PacketHeader* PacketParser::pull_bytes(
 
 void PacketParser::push_bytes(
     PacketRunner& packet_runner,
+    const uint32_t& session_id,
     const uint8_t* data, size_t bytes
 ){
 //    cout << std::string((const char*)data, bytes) << endl;
@@ -206,7 +210,9 @@ void PacketParser::push_bytes(
 
             //  Verify the CRC.
 
-            uint32_t actual_crc = 0xffffffff;
+            uint32_t actual_crc = header->opcode == PABB2_CONNECTION_OPCODE_ASK_RESET
+                ? 0xffffffff
+                : session_id;
             pabb_crc32_buffer(&actual_crc, m_buffer, packet_bytes - sizeof(uint32_t));
 
             uint32_t expected_crc;

Common/PABotBase2/ReliableConnectionLayer/PABotBase2_PacketParser.h

@@ -62,6 +62,7 @@ struct PacketParser{
     //
     const PacketHeader* pull_bytes(
         UnreliableStreamConnectionPolling& connection,
+        const uint32_t& session_id,
         WallDuration timeout
     );
 
@@ -72,6 +73,7 @@ struct PacketParser{
     //
     void push_bytes(
         PacketRunner& packet_runner,
+        const uint32_t& session_id,
         const uint8_t* data, size_t bytes
     );
 

Common/PABotBase2/ReliableConnectionLayer/PABotBase2_PacketProtocol.h

@@ -32,49 +32,35 @@ namespace PABotBase2{
 //
 
 #define PABB2_CONNECTION_MAGIC_NUMBER               0x81
-#define PABB2_CONNECTION_PROTOCOL_VERSION           2026041102
+#define PABB2_CONNECTION_PROTOCOL_VERSION           2026050100
 
 
 #define PABB2_CONNECTION_RETRANSMIT_FLAG            0x80
 #define PABB2_CONNECTION_OPCODE_MASK                0x7f
 
+#define PABB2_CONNECTION_OPCODE_INVALID             0x00
+
 
 //
-//  Special
+//  Packets
 //
 
+using SessionId = uint32_t;
+
 struct PABB_PACK PacketHeader{
     uint8_t magic_number;
     uint8_t seqnum;
     uint8_t packet_bytes;
     uint8_t opcode;
 };
 
-#define PABB2_CONNECTION_OPCODE_INVALID             0x00
-
-#define PABB2_CONNECTION_OPCODE_ASK_RESET           0x01
-#define PABB2_CONNECTION_OPCODE_RET_RESET           0x41
-
-
-struct PABB_PACK PacketHeader_u8{
-    uint8_t magic_number;
-    uint8_t seqnum;
-    uint8_t packet_bytes;
-    uint8_t opcode;
+struct PABB_PACK PacketHeader_u8 : PacketHeader{
     uint8_t data;
 };
-struct PABB_PACK PacketHeader_u16{
-    uint8_t magic_number;
-    uint8_t seqnum;
-    uint8_t packet_bytes;
-    uint8_t opcode;
+struct PABB_PACK PacketHeader_u16 : PacketHeader{
     uint16_t data;
 };
-struct PABB_PACK PacketHeader_u32{
-    uint8_t magic_number;
-    uint8_t seqnum;
-    uint8_t packet_bytes;
-    uint8_t opcode;
+struct PABB_PACK PacketHeader_u32 : PacketHeader{
     uint32_t data;
 };
 
@@ -84,6 +70,9 @@ struct PABB_PACK PacketHeader_u32{
 //  Requests (acks required)
 //
 
+#define PABB2_CONNECTION_OPCODE_ASK_RESET           0x01
+#define PABB2_CONNECTION_OPCODE_RET_RESET           0x41
+
 #define PABB2_CONNECTION_OPCODE_ASK_VERSION         0x02
 #define PABB2_CONNECTION_OPCODE_RET_VERSION         0x42
 
@@ -99,11 +88,7 @@ struct PABB_PACK PacketHeader_u32{
 #define PABB2_CONNECTION_OPCODE_ASK_STREAM_DATA         0x12
 #define PABB2_CONNECTION_OPCODE_RET_STREAM_DATA         0x52
 #define PABB2_CONNECTION_OPCODE_ASK_STREAM_REQUEST      0x13    //  Unused for now.
-struct PABB_PACK PacketHeaderData{
-    uint8_t magic_number;
-    uint8_t seqnum;
-    uint8_t packet_bytes;
-    uint8_t opcode;
+struct PABB_PACK PacketHeaderData : PacketHeader{
     uint16_t stream_offset;
 };
 
@@ -135,7 +120,6 @@ struct PABB_PACK PacketHeaderData{
 #define PABB2_CONNECTION_OPCODE_UNKNOWN_OPCODE          0x32
 
 
-
 }
 }