Usermode/DHCPC - Bugfixing and implementing select() timeouts

diff --git a/Usermode/Applications/dhcpclient_src/main.c b/Usermode/Applications/dhcpclient_src/main.c
index 7c0b072..7295788 100644 (file)
--- a/Usermode/Applications/dhcpclient_src/main.c
+++ b/Usermode/Applications/dhcpclient_src/main.c
@@ -1,4 +1,6 @@
 /*
+ * 
+ * http://www.ietf.org/rfc/rfc2131.txt
  */
 #include <unistd.h>
 #include <stdint.h>
@@ -63,6 +65,11 @@ typedef struct sInterface
         int    Num;
         int    SocketFD;
         int    IfaceFD;
+
+       uint32_t        TransactionID;
+       char    HWAddr[6];
+       
+       int64_t Timeout;
 } tInterface;
 
 // === PROTOTYPES ===
@@ -72,6 +79,8 @@ int   Start_Interface(tInterface *Iface);
 void   Send_DHCPDISCOVER(tInterface *Iface);
 void   Send_DHCPREQUEST(tInterface *Iface, void *OfferBuffer, int TypeOffset);
 int    Handle_Packet(tInterface *Iface);
+void   Handle_Timeout(tInterface *Iface);
+void   Update_State(tInterface *Iface, int newState);
 void   SetAddress(tInterface *Iface, void *Addr, void *Mask, void *Router);
 
 // === CODE ===
@@ -96,10 +105,10 @@ int main(int argc, char *argv[])
 
        for( i = ifaces; i; i = i->Next )
        {
-               i->State = STATE_PREINIT;
                if( Start_Interface(i) < 0 ) {
                        return -1;
                }
+               i->State = STATE_PREINIT;
                
                // Send request
                Send_DHCPDISCOVER(i);
@@ -110,6 +119,7 @@ int main(int argc, char *argv[])
                 int    maxfd;
                fd_set  fds;
                tInterface      *p;
+               int64_t timeout = 1000;
        
                maxfd = 0;
                FD_ZERO(&fds);
@@ -118,12 +128,15 @@ int main(int argc, char *argv[])
                        FD_SET(i->SocketFD, &fds);
                        if(maxfd < i->SocketFD) maxfd = i->SocketFD;
                }
-               if( select(maxfd+1, &fds, NULL, NULL, NULL) < 0 )
+               
+               if( select(maxfd+1, &fds, NULL, NULL, &timeout) < 0 )
                {
                        // TODO: Check error result
                        return -1;
                }
 
+               _SysDebug("select() returned");
+
                // Check for changes (with magic to allow inline deletion)
                for( p = (void*)&ifaces, i = ifaces; i; p=i,i = i->Next )
                {
@@ -138,6 +151,11 @@ int main(int argc, char *argv[])
                                        i = p;
                                }
                        }
+                       
+                       if( _SysTimestamp() > i->Timeout )
+                       {
+                               Handle_Timeout(i);
+                       }
                }
        }
        return 0;
@@ -175,6 +193,20 @@ int Start_Interface(tInterface *Iface)
        
        // TODO: Check that the adapter is not in use
        
+       // Request MAC address from network adapter
+       {
+               char    path[] = "/Devices/ip/adapters/ethXXXX";
+               sprintf(path, "/Devices/ip/adapters/%s", Iface->Adapter);
+               fd = open(path, 0);
+               if(fd == -1) {
+                       _SysDebug("Unable to open adapter %s", path);
+                       return -1;
+               }
+               ioctl(fd, 4, Iface->HWAddr);
+               // TODO: Check if ioctl() failed
+               close(fd);
+       }
+       
        // Initialise an interface, with a dummy IP address (zero)
        fd = open("/Devices/ip", 0);
        if( fd == -1 ) {
@@ -215,6 +247,10 @@ int Start_Interface(tInterface *Iface)
        return 0;
 }
 
+void Send_DHCPRELEASE(tInterface *Iface)
+{
+}
+
 void Send_DHCPDISCOVER(tInterface *Iface)
 {
        uint32_t        transaction_id;
@@ -222,7 +258,10 @@ void Send_DHCPDISCOVER(tInterface *Iface)
        char    data[8 + sizeof(struct sDHCP_Message) + 3 + 1];
        msg = (void*)data + 8;
        
+       _SysDebug("DHCPDISCOVER to %s", Iface->Adapter);
+
        transaction_id = rand();
+       Iface->TransactionID = transaction_id;
 
        msg->op    = htonb(1);  // BOOTREQUEST
        msg->htype = htonb(1);  // 10mb Ethernet
@@ -230,25 +269,13 @@ void Send_DHCPDISCOVER(tInterface *Iface)
        msg->hops  = htonb(0);  // Hop count so far
        msg->xid   = htonl(transaction_id);     // Transaction ID
        msg->secs  = htons(0);  // secs - No time has elapsed
-       msg->flags = htons(0);  // flags - TODO: Check if broadcast bit need be set
+       msg->flags = htons(0x0000);     // flags - Broadcast is unset
        msg->ciaddr = htonl(0); // ciaddr - Zero, as we don't have one yet
        msg->yiaddr = htonl(0); // yiaddr - Zero?
        msg->siaddr = htonl(0); // siaddr - Zero? maybe -1
        msg->giaddr = htonl(0); // giaddr - Zero?
-       // Request MAC address from network adapter
-       {
-               char    path[] = "/Devices/ip/adapters/ethXXXX";
-               sprintf(path, "/Devices/ip/adapters/%s", Iface->Adapter);
-               int fd = open(path, 0);
-               if(fd == -1) {
-                       _SysDebug("Unable to open adapter %s", path);
-               }
-               else {
-                       ioctl(fd, 4, msg->chaddr);
-                       // TODO: Check if ioctl() failed
-                       close(fd);
-               }
-       }
+       memcpy(msg->chaddr, Iface->HWAddr, 6);
+
        memset(msg->sname, 0, sizeof(msg->sname));      // Nuke the rest
        memset(msg->file, 0, sizeof(msg->file));        // Nuke the rest
        msg->dhcp_magic = htonl(DHCP_MAGIC);
@@ -265,21 +292,53 @@ void Send_DHCPDISCOVER(tInterface *Iface)
        data[4] = 255;  data[5] = 255;  data[6] = 255;  data[7] = 255;
 
        write(Iface->SocketFD, data, sizeof(data));
-       Iface->State = STATE_DISCOVER_SENT;
+       Update_State(Iface, STATE_DISCOVER_SENT);
 }
 
 void Send_DHCPREQUEST(tInterface *Iface, void *OfferPacket, int TypeOffset)
 {
        struct sDHCP_Message    *msg;
+        int    i;
        msg = (void*) ((char*)OfferPacket) + 8;
 
        // Reuses old data :)
-       msg->op = 1;
-       msg->options[TypeOffset+2] = 3; // DHCPREQUEST
-       msg->options[TypeOffset+3] = 255;
+       msg->op    = 1;
+       msg->htype = 1;
+       msg->hlen  = 6;
+       msg->hops  = 0;
+       msg->xid   = msg->xid;
+       msg->secs  = htons(0);  // TODO: Maintain times
+       msg->flags = htons(0);
+       memcpy(msg->chaddr, Iface->HWAddr, 6);
+       memset(msg->sname, 0, sizeof(msg->sname));      // Nuke the rest
+       memset(msg->file, 0, sizeof(msg->file));        // Nuke the rest
+
+       i = 0;
+       msg->options[i++] = 53; // Message type = DHCPREQUEST
+       msg->options[i++] = 1;
+       msg->options[i++] = 3;
+       msg->options[i++] = 50; // Requested Address
+       msg->options[i++] = 4;
+       memcpy(msg->options + i, &msg->yiaddr, 4);      i += 4;
+//     msg->options[i++] = 54; // Server identifier
+//     msg->options[i++] = 4;
+//     memcpy(msg->options + i, (char*)OfferPacket + 4, 4);    i += 4;
+       msg->options[i++] = 255;
        
-       write(Iface->SocketFD, OfferPacket, 8 + sizeof(*msg) + TypeOffset + 4);
-       Iface->State = STATE_REQUEST_SENT;
+       // Clear last because yiaddr is needed in option setup
+       msg->ciaddr = htonl(0);
+       msg->yiaddr = htonl(0);
+       msg->siaddr = htonl(0);
+       msg->giaddr = htonl(0);
+
+       // HACK
+       ((uint8_t*)OfferPacket)[4] = 255;
+       ((uint8_t*)OfferPacket)[5] = 255;
+       ((uint8_t*)OfferPacket)[6] = 255;
+       ((uint8_t*)OfferPacket)[7] = 255;
+       
+       write(Iface->SocketFD, OfferPacket, 8 + sizeof(*msg) + i);
+       Update_State(Iface, STATE_REQUEST_SENT);
 }
 
 int Handle_Packet(tInterface *Iface)
@@ -314,6 +373,19 @@ int Handle_Packet(tInterface *Iface)
                return 0;
        }       
 
+
+       // Check if the packet is related to our requests
+       if( ntohl(msg->xid) != Iface->TransactionID ) {
+               _SysDebug("Transaction ID mis-match, ignoring (0x%x != 0x%x)",
+                       ntohl(msg->xid), Iface->TransactionID);
+               return 0;
+       }
+       if( memcmp(msg->chaddr, Iface->HWAddr, 6) != 0 ) {
+               _SysDebug("Hardware address mis-match, ignoring");
+               return 0;
+       }
+
+       // Parse options
        i = 0;
        while( i < len - sizeof(*msg) - 8 && msg->options[i] != 255 )
        {
@@ -357,13 +429,41 @@ int Handle_Packet(tInterface *Iface)
        case 4: // DHCPDECLINE - ?
                break;
        case 5: // DHCPACK
-               // TODO: Apply address
                SetAddress(Iface, &msg->yiaddr, subnet_mask, router);
+               // Return 1 to remove from list
                return 1;
        }
        return 0;
 }
 
+void Handle_Timeout(tInterface *Iface)
+{
+       switch(Iface->State)
+       {
+       case STATE_DISCOVER_SENT:
+               Send_DHCPDISCOVER(Iface);
+               break;
+       default:
+               _SysDebug("Timeout with state = %i", Iface->State);
+               break;
+       }
+}
+
+void Update_State(tInterface *Iface, int newState)
+{
+       if( Iface->State != newState )
+       {
+               Iface->Timeout = _SysTimestamp() + 500;
+               Iface->State = newState;
+       }
+       else
+       {
+               // TODO: Exponential backoff
+               Iface->Timeout = _SysTimestamp() + 3000;
+               _SysDebug("State %i repeated, timeout is 3000ms now", newState);
+       }
+}
+
 void SetAddress(tInterface *Iface, void *Addr, void *Mask, void *Router)
 {
         int    mask_bits = 0;  

diff --git a/Usermode/Libraries/ld-acess.so_src/arch/syscalls.s.h b/Usermode/Libraries/ld-acess.so_src/arch/syscalls.s.h
index 88cea59..cd7b8fe 100644 (file)
--- a/Usermode/Libraries/ld-acess.so_src/arch/syscalls.s.h
+++ b/Usermode/Libraries/ld-acess.so_src/arch/syscalls.s.h
@@ -20,6 +20,7 @@ SYSCALL1(setgid, SYS_SETGID)
 
 SYSCALL1(SysSetName, SYS_SETNAME)
 SYSCALL2(SysGetName, SYS_GETNAME)
+SYSCALL0(_SysTimestamp, SYS_GETTIME)
 
 SYSCALL1(SysSetPri, SYS_SETPRI)
 

diff --git a/Usermode/Libraries/ld-acess.so_src/export.c b/Usermode/Libraries/ld-acess.so_src/export.c
index 41ba01f..1062d7e 100644 (file)
--- a/Usermode/Libraries/ld-acess.so_src/export.c
+++ b/Usermode/Libraries/ld-acess.so_src/export.c
@@ -40,6 +40,8 @@ const struct {
        EXP(SysSetName),
        //EXP(SysGetName),
 
+       EXP(_SysTimestamp),
+
        //EXP(SysSetPri),
 
        EXP(SysSendMessage),

diff --git a/Usermode/include/acess/sys.h b/Usermode/include/acess/sys.h
index cdd0187..e91ffb6 100644 (file)
--- a/Usermode/include/acess/sys.h
+++ b/Usermode/include/acess/sys.h
@@ -53,6 +53,7 @@ extern int    getpid(void);
 extern int     _SysSetFaultHandler(int (*Handler)(int));
 extern void    SysSetName(const char *Name);
 //extern int   SysGetName(const char *Name);
+extern int64_t _SysTimestamp(void);
 
 // --- Permissions ---
 extern int     getuid(void);