start working on melonAP.

it sends beacons!

src/Wifi.cpp

@@ -21,6 +21,7 @@
 #include "NDS.h"
 #include "SPI.h"
 #include "Wifi.h"
+#include "WifiAP.h"
 #include "Platform.h"
 
 
@@ -126,6 +127,8 @@ bool Init()
     MPInited = false;
     LANInited = false;
 
+    WifiAP::Init();
+
     return true;
 }
 
@@ -135,6 +138,8 @@ void DeInit()
         Platform::MP_DeInit();
     if (LANInited)
         Platform::LAN_DeInit();
+
+    WifiAP::DeInit();
 }
 
 void Reset()
@@ -204,6 +209,8 @@ void Reset()
     MPNumReplies = 0;
 
     CmdCounter = 0;
+
+    WifiAP::Reset();
 }
 
 
@@ -767,7 +774,7 @@ bool CheckRX(bool block)
     for (;;)
     {
         int rxlen = Platform::MP_RecvPacket(RXBuffer, block);
-        //if (rxlen == 0) rxlen = Platform::LAN_RecvPacket(RXBuffer);
+        if (rxlen == 0) rxlen = WifiAP::RecvPacket(RXBuffer);
         if (rxlen == 0) return false;
         if (rxlen < 12+24) continue;
 
@@ -909,6 +916,8 @@ void MSTimer()
 
 void USTimer(u32 param)
 {
+    WifiAP::USTimer();
+
     if (IOPORT(W_USCountCnt))
     {
         USCounter++;
@@ -1478,4 +1487,15 @@ void Write(u32 addr, u16 val)
     IOPORT(addr&0xFFF) = val;
 }
 
+
+u8* GetMAC()
+{
+    return (u8*)&IOPORT(W_MACAddr0);
+}
+
+u8* GetBSSID()
+{
+    return (u8*)&IOPORT(W_BSSID0);
+}
+
 }

src/Wifi.h

@@ -154,6 +154,9 @@ void USTimer(u32 param);
 u16 Read(u32 addr);
 void Write(u32 addr, u16 val);
 
+u8* GetMAC();
+u8* GetBSSID();
+
 }
 
 #endif

src/WifiAP.cpp

@@ -18,6 +18,7 @@
 
 #include <stdio.h>
 #include <string.h>
+#include "NDS.h"
 #include "Wifi.h"
 #include "WifiAP.h"
 
@@ -25,6 +26,137 @@
 namespace WifiAP
 {
 
+#define AP_MAC  0x00, 0xF0, 0x77, 0x77, 0x77, 0x77
+#define AP_NAME "melonAP"
+
+const u8 APMac[6] = {AP_MAC};
+
+#define PWRITE_8(p, v)      *p++ = v;
+#define PWRITE_16(p, v)     *(u16*)p = v; p += 2;
+#define PWRITE_32(p, v)     *(u32*)p = v; p += 4;
+#define PWRITE_64(p, v)     *(u64*)p = v; p += 8;
+
+#define PWRITE_MAC(p, a,b,c,d,e,f) \
+    *p++ = a; *p++ = b; *p++ = c; *p++ = d; *p++ = e; *p++ = f;
+
+#define PWRITE_MAC2(p, m) \
+    *p++ = m[0]; *p++ = m[1]; *p++ = m[2]; *p++ = m[3]; *p++ = m[4]; *p++ = m[5];
+
+#define PWRITE_SEQNO(p)     PWRITE_16(p, SeqNo); SeqNo += 0x10;
+
+#define PWRITE_TXH(p, len, rate) \
+    PWRITE_16(p, 0); \
+    PWRITE_16(p, 0); \
+    PWRITE_16(p, 0); \
+    PWRITE_16(p, 0); \
+    PWRITE_8(p, rate); \
+    PWRITE_8(p, 0); \
+    PWRITE_16(p, len);
+
+//#define PALIGN_4(p, base)  p += ((4 - ((ptrdiff_t)(p-base) & 0x3)) & 0x3);
+// no idea what is the ideal padding there
+// but in the case of management frames the padding shouldn't be counted as an information element
+#define PLEN(p, base)      (int)(ptrdiff_t)(p-base)
+#define PALIGN_4(p, base)  while (PLEN(p,base) & 0x3) *p++ = 0xFF;
+
+
+u64 USCounter;
+
+u16 SeqNo;
+
+bool BeaconDue;
+
+u8 PacketBuffer[2048];
+int PacketLen;
+int RXNum;
+
+
+bool Init()
+{
+    return true;
+}
+
+void DeInit()
+{
+}
+
+void Reset()
+{
+    // random starting point for the counter
+    USCounter = 0x428888017ULL;
+    SeqNo = 0x0120;
+
+    BeaconDue = false;
+
+    memset(PacketBuffer, 0, sizeof(PacketBuffer));
+    PacketLen = 0;
+    RXNum = 0;
+}
+
+
+void USTimer()
+{
+    USCounter++;
+
+    u32 chk = (u32)USCounter;
+    if (!(chk & 0x1FFFF))
+    {
+        // send beacon every 128ms
+        BeaconDue = true;
+    }
+}
+
+
+int SendPacket(u8* data, int len)
+{
     //
+}
+
+int RecvPacket(u8* data)
+{
+    if (BeaconDue)
+    {
+        BeaconDue = false;
+
+        // craft beacon
+        u8* base = data + 12;
+        u8* p = base;
+
+        PWRITE_16(p, 0x0080);
+        PWRITE_16(p, 0x0000); // duration??
+        PWRITE_MAC(p, 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF); // recv
+        PWRITE_MAC2(p, APMac); // sender
+        PWRITE_MAC2(p, APMac); // BSSID
+        PWRITE_SEQNO(p);
+
+        PWRITE_64(p, USCounter);
+        PWRITE_16(p, 128); // beacon interval
+        PWRITE_16(p, 0x0021); // capability
+        PWRITE_8(p, 0x01); PWRITE_8(p, 0x02); PWRITE_8(p, 0x82); PWRITE_8(p, 0x84); // rates
+        PWRITE_8(p, 0x03); PWRITE_8(p, 0x01); PWRITE_8(p, 0x06); // current channel
+        PWRITE_8(p, 0x05); PWRITE_8(p, 0x04); PWRITE_8(p, 0); PWRITE_8(p, 0); PWRITE_8(p, 0); PWRITE_8(p, 0); // TIM
+        PWRITE_8(p, 0x00); PWRITE_8(p, strlen(AP_NAME));
+        memcpy(p, AP_NAME, strlen(AP_NAME)); p += strlen(AP_NAME);
+
+        PALIGN_4(p, base);
+        PWRITE_32(p, 0xDEADBEEF); // checksum. doesn't matter for now
+
+        int len = PLEN(p, base);
+        p = data;
+        PWRITE_TXH(p, len, 20);
+
+        /*static int zorp=0;
+        zorp++;
+        char derp[55];
+        sprintf(derp, "derpo%d.bin", zorp);
+        FILE* f = fopen(derp, "wb");
+        fwrite(data, len+12, 1, f);
+        fclose(f);*/
+
+        return len+12;
+    }
+
+    return 0;
+}
 
 }

src/WifiAP.h

@@ -26,7 +26,11 @@ bool Init();
 void DeInit();
 void Reset();
 
-//
+void USTimer();
+
+// packet format: 12-byte TX header + original 802.11 frame
+int SendPacket(u8* data, int len);
+int RecvPacket(u8* data);
 
 }
 

src/libui_sdl/Platform.cpp

@@ -91,6 +91,7 @@ u8 PacketBuffer[2048];
 const char* PCapLibNames[] =
 {
 #ifdef __WIN32__
+    // TODO: name for npcap in non-WinPCap mode
     "wpcap.dll",
 #else
     // TODO: Linux lib names