feat: add NTP; fix networking bugs/regressions

kernel/src/Api/BuildNo.hpp

@@ -12,4 +12,4 @@
 
 #pragma once
 
-#define MONTAUK_BUILD_NUMBER 8
+#define MONTAUK_BUILD_NUMBER 17

kernel/src/Api/Net.hpp

@@ -12,6 +12,7 @@
 #include <Timekeeping/ApicTimer.hpp>
 #include <Net/Icmp.hpp>
 #include <Net/Dns.hpp>
+#include <Net/Ipv4.hpp>
 #include <Net/Socket.hpp>
 #include <Net/NetConfig.hpp>
 #include <Drivers/Net/E1000.hpp>
@@ -82,6 +83,10 @@ namespace montauk::abi {
 
     static int Sys_RecvFrom(int fd, uint8_t* buf, uint32_t maxLen,
                             uint32_t* srcIp, uint16_t* srcPort) {
+        // A preceding UDP send may be queued while ARP resolves the next hop.
+        // Drive the pending IPv4 queue on each non-blocking receive so a lost
+        // initial ARP request is retried without unrelated network traffic.
+        Net::Ipv4::FlushPending();
         return Net::Socket::RecvFrom(fd, buf, maxLen, srcIp, srcPort, Sched::GetCurrentPid());
     }
 

kernel/src/Api/Syscall.cpp

@@ -174,6 +174,8 @@ namespace montauk::abi {
                 if (!UserMemory::Writable<DateTime>(frame->arg1)) return -1;
                 Sys_GetTime((DateTime*)frame->arg1);
                 return 0;
+            case SYS_SETUNIXTIME:
+                return Sys_SetUnixTime((int64_t)frame->arg1);
             case SYS_SOCKET:
                 return (int64_t)Sys_Socket((int)frame->arg1);
             case SYS_CONNECT:
@@ -556,7 +558,7 @@ namespace montauk::abi {
         Hal::WriteMSR(Hal::IA32_FMASK, 0x200);
 
         Kt::KernelLogStream(Kt::OK, "Syscall") << "SYSCALL/SYSRET initialized (LSTAR="
-            << kcp::hex << (uint64_t)SyscallEntry << kcp::dec << ", 124 syscall slots)";
+            << kcp::hex << (uint64_t)SyscallEntry << kcp::dec << ", 154 syscall slots)";
     }
 
 }

kernel/src/Api/Syscall.hpp

@@ -287,6 +287,7 @@ namespace montauk::abi {
 
     // Path metadata (size, timestamps, mode). (const char* path, FileStat* out) -> 0, -1 on error/unsupported.
     static constexpr uint64_t SYS_STAT                = 152;
+    static constexpr uint64_t SYS_SETUNIXTIME         = 153;
 
     // Tunable parameters (for SYS_SDR_SETPARAM / SYS_SDR_GETPARAM).
     static constexpr int SDR_PARAM_FREQ        = 0;  // center frequency, Hz

kernel/src/Api/Time.hpp

@@ -38,4 +38,8 @@ namespace montauk::abi {
     static int64_t Sys_GetTZ() {
         return (int64_t)Timekeeping::GetTZOffset();
     }
-};
+
+    static int64_t Sys_SetUnixTime(int64_t unixSeconds) {
+        return Timekeeping::SetUnixTimestamp(unixSeconds) ? 0 : -1;
+    }
+};

kernel/src/Drivers/Net/E1000.cpp

@@ -250,7 +250,10 @@ namespace Drivers::Net::E1000 {
             KernelLogStream(INFO, "E1000") << "Link status change: " << (linkUp ? "UP" : "DOWN");
         }
 
-        if (icr & ICR_RXT0) {
+        // Both receive-timer and descriptor-threshold causes mean completed
+        // RX descriptors may be waiting. ICR is clear-on-read, so ignoring
+        // RXDMT0 can strand a lone packet until unrelated traffic arrives.
+        if (icr & (ICR_RXT0 | ICR_RXDMT0)) {
             // Process received packets
             while (true) {
                 uint32_t nextIdx = (g_rxTail + 1) % RX_DESC_COUNT;

kernel/src/Drivers/Net/E1000E.cpp

@@ -477,7 +477,10 @@ namespace Drivers::Net::E1000E {
             KernelLogStream(INFO, "E1000E") << "Link status change: " << (linkUp ? "UP" : "DOWN");
         }
 
-        if (icr & ICR_RXT0) {
+        // Both receive-timer and descriptor-threshold causes mean completed
+        // RX descriptors may be waiting. ICR is clear-on-read, so ignoring
+        // RXDMT0 can strand a lone packet until unrelated traffic arrives.
+        if (icr & (ICR_RXT0 | ICR_RXDMT0)) {
             while (true) {
                 uint32_t nextIdx = (g_rxTail + 1) % RX_DESC_COUNT;
                 RxDescriptor& desc = g_rxDescs[nextIdx];

kernel/src/Net/Dns.cpp

@@ -8,6 +8,7 @@
 #include <Net/Udp.hpp>
 #include <Net/ByteOrder.hpp>
 #include <Net/NetConfig.hpp>
+#include <Net/Ipv4.hpp>
 #include <Libraries/Memory.hpp>
 #include <Libraries/String.hpp>
 #include <Timekeeping/ApicTimer.hpp>
@@ -409,12 +410,21 @@ namespace Net::Dns {
 
         // Wait for response with timeout
         uint64_t start = Timekeeping::GetMilliseconds();
+        uint64_t lastPendingService = start;
         while (!query->gotResponse) {
-            if (Timekeeping::GetMilliseconds() - start >= timeoutMs) {
+            uint64_t now = Timekeeping::GetMilliseconds();
+            if (now - start >= timeoutMs) {
                 Net::Udp::Unbind(query->localPort);
                 query->active = false;
                 return 0;
             }
+            // Ipv4::Send may have queued this DNS datagram while resolving the
+            // gateway MAC. Drive that pending queue here so ARP coalescing can
+            // retry a lost initial request without requiring unrelated traffic.
+            if (now - lastPendingService >= 100) {
+                Net::Ipv4::FlushPending();
+                lastPendingService = now;
+            }
             Sched::Schedule();
         }
 

kernel/src/Timekeeping/Time.cpp

@@ -84,6 +84,13 @@ int64_t Timekeeping::GetUnixTimestamp() {
     return g_bootEpoch + (int64_t)(Timekeeping::GetMilliseconds() / 1000);
 }
 
+bool Timekeeping::SetUnixTimestamp(int64_t unixSeconds) {
+    if (unixSeconds < 0 || unixSeconds > 4102444799LL)
+        return false;
+    g_bootEpoch = unixSeconds - (int64_t)(Timekeeping::GetMilliseconds() / 1000);
+    return true;
+}
+
 Timekeeping::DateTime Timekeeping::GetDateTime() {
     return EpochToDate(GetUnixTimestamp() + (int64_t)g_tzOffsetMinutes * 60);
 }
@@ -94,4 +101,4 @@ void Timekeeping::SetTZOffset(int totalMinutes) {
 
 int Timekeeping::GetTZOffset() {
     return g_tzOffsetMinutes;
-}
+}

kernel/src/Timekeeping/Time.hpp

@@ -53,6 +53,7 @@ namespace Timekeeping {
     void Init(uint16_t Year, uint8_t Month, uint8_t Day, uint8_t Hour, uint8_t Minute, uint8_t Second);
     int64_t GetUnixTimestamp();
     DateTime GetDateTime();
+    bool SetUnixTimestamp(int64_t unixSeconds);
 
     void SetTZOffset(int totalMinutes);
     int GetTZOffset();