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-rw-r--r--src/libui_sdl/LAN_Socket.cpp219
1 files changed, 93 insertions, 126 deletions
diff --git a/src/libui_sdl/LAN_Socket.cpp b/src/libui_sdl/LAN_Socket.cpp
index 8111517..9088ac8 100644
--- a/src/libui_sdl/LAN_Socket.cpp
+++ b/src/libui_sdl/LAN_Socket.cpp
@@ -75,7 +75,8 @@ typedef struct
u16 SourcePort;
u16 DestPort;
- u32 SeqNum;
+ u32 SeqNum; // sequence number for incoming frames
+ u32 AckNum;
// 0: unused
// 1: connected
@@ -184,127 +185,6 @@ void FinishTCPFrame(u8* data, int len)
}
-/*bool HandleIncomingIPFrame(u8* data, int len)
-{
- const u32 serverip = 0x0A404001;
- const u32 clientip = 0x0A404010;
-
- //if (memcmp(&data[0x1E], PCapAdapterData->IP_v4, 4))
- // return false;
-
- u8 protocol = data[0x17];
-
- //memcpy(&data[6], &PCapAdapterData->DHCP_MAC[0], 6);
- memcpy(&data[0], Wifi::GetMAC(), 6);
- data[6] = 0x00; data[7] = 0xAB; data[8] = 0x33;
- data[9] = 0x28; data[10] = 0x99; data[11] = 0x44;
-
- *(u32*)&data[0x1E] = htonl(clientip);
-
- u8* ipheader = &data[0xE];
- u8* protoheader = &data[0x22];
-
- // IP checksum
- u32 tmp = 0;
-
- *(u16*)&ipheader[10] = 0;
- for (int i = 0; i < 20; i += 2)
- tmp += ntohs(*(u16*)&ipheader[i]);
- while (tmp >> 16)
- tmp = (tmp & 0xFFFF) + (tmp >> 16);
- tmp ^= 0xFFFF;
- *(u16*)&ipheader[10] = htons(tmp);
-
- if (protocol == 0x11)
- {
- u32 udplen = ntohs(*(u16*)&protoheader[4]);
-
- // UDP checksum
- tmp = 0;
- *(u16*)&protoheader[6] = 0;
- tmp += ntohs(*(u16*)&ipheader[12]);
- tmp += ntohs(*(u16*)&ipheader[14]);
- tmp += ntohs(*(u16*)&ipheader[16]);
- tmp += ntohs(*(u16*)&ipheader[18]);
- tmp += ntohs(0x1100);
- tmp += udplen;
- for (u8* i = protoheader; i < &protoheader[udplen-1]; i += 2)
- tmp += ntohs(*(u16*)i);
- if (udplen & 1) tmp += (protoheader[udplen-1] << 8);
- while (tmp >> 16)
- tmp = (tmp & 0xFFFF) + (tmp >> 16);
- tmp ^= 0xFFFF;
- if (tmp == 0) tmp = 0xFFFF;
- *(u16*)&protoheader[6] = htons(tmp);
- }
- else if (protocol == 0x06)
- {
- u32 tcplen = ntohs(*(u16*)&ipheader[2]) - 0x14;
-
- u16 srcport = ntohs(*(u16*)&protoheader[0]);
- u16 dstport = ntohs(*(u16*)&protoheader[2]);
- u16 flags = ntohs(*(u16*)&protoheader[12]);
-
- // TODO: check if they send a FIN, I guess
- int sockid = -1;
- for (int i = 0; i < (sizeof(TCPSocketList)/sizeof(TCPSocket)); i++)
- {
- TCPSocket* sock = &TCPSocketList[i];
- if (sock->Status == 1 && !memcmp(&sock->DestIP, &ipheader[12], 4) && sock->DestPort == srcport)
- {
- sockid = i;
- break;
- }
- }
-
- if (sockid == -1)
- {
- return true;
- }
-
- // TCP checksum
- tmp = 0;
- *(u16*)&protoheader[16] = 0;
- tmp += ntohs(*(u16*)&ipheader[12]);
- tmp += ntohs(*(u16*)&ipheader[14]);
- tmp += ntohs(*(u16*)&ipheader[16]);
- tmp += ntohs(*(u16*)&ipheader[18]);
- tmp += ntohs(0x0600);
- tmp += tcplen;
- for (u8* i = protoheader; i < &protoheader[tcplen-1]; i += 2)
- tmp += ntohs(*(u16*)i);
- if (tcplen & 1) tmp += (protoheader[tcplen-1] << 8);
- while (tmp >> 16)
- tmp = (tmp & 0xFFFF) + (tmp >> 16);
- tmp ^= 0xFFFF;
- *(u16*)&protoheader[16] = htons(tmp);
- }
-
- return false;
-}*/
-
-/*void RXCallback(u_char* blarg, const struct pcap_pkthdr* header, const u_char* data)
-{
- while (PCapRXNum > 0);
-
- if (header->len > 2048-64) return;
-
- PCapPacketLen = header->len;
- memcpy(PCapPacketBuffer, data, PCapPacketLen);
- PCapRXNum = 1;
-
- if (!Config::DirectLAN)
- {
- u16 ethertype = ntohs(*(u16*)&data[0xC]);
-
- if (ethertype == 0x0800) // IPv4
- {
- if (HandleIncomingIPFrame(PCapPacketBuffer, header->len))
- PCapRXNum = 0;
- }
- }
-}*/
-
void HandleDHCPFrame(u8* data, int len)
{
u8 type = 0xFF;
@@ -602,6 +482,8 @@ void TCP_SYNACK(TCPSocket* sock, u8* data, int len)
u8* tcpheader = &data[0x22];
u32 seqnum = htonl(*(u32*)&tcpheader[4]);
+ seqnum++;
+ sock->AckNum = seqnum;
// ethernet
memcpy(out, &data[6], 6); out += 6;
@@ -627,7 +509,7 @@ void TCP_SYNACK(TCPSocket* sock, u8* data, int len)
*(u16*)out = *(u16*)&tcpheader[2]; out += 2; // source port
*(u16*)out = *(u16*)&tcpheader[0]; out += 2; // destination port
*(u32*)out = htonl(sock->SeqNum); out += 4; sock->SeqNum++; // seq number
- *(u32*)out = htonl(seqnum+1); out += 4; // ack seq number
+ *(u32*)out = htonl(seqnum); out += 4; // ack seq number
*(u16*)out = htons(0x8012); out += 2; // flags (SYN+ACK)
*(u16*)out = htons(0x7000); out += 2; // window size (uuuh)
*(u16*)out = 0; out += 2; // checksum
@@ -656,6 +538,58 @@ void TCP_SYNACK(TCPSocket* sock, u8* data, int len)
RXNum = 1;
}
+void TCP_BuildIncomingFrame(TCPSocket* sock, u8* data, int len)
+{
+ u8 resp[2048];
+ u8* out = &resp[0];
+
+ if (len > 1536) return;
+
+ // ethernet
+ memcpy(out, Wifi::GetMAC(), 6); out += 6; // hurf
+ memcpy(out, kServerMAC, 6); out += 6;
+ *(u16*)out = htons(0x0800); out += 2;
+
+ // IP
+ u8* resp_ipheader = out;
+ *out++ = 0x45;
+ *out++ = 0x00;
+ *(u16*)out = 0; out += 2; // total length
+ *(u16*)out = htons(IPv4ID); out += 2; IPv4ID++;
+ *out++ = 0x00;
+ *out++ = 0x00;
+ *out++ = 0x80; // TTL
+ *out++ = 0x06; // protocol (TCP)
+ *(u16*)out = 0; out += 2; // checksum
+ memcpy(out, sock->DestIP, 4); out += 4; // source IP
+ *(u32*)out = htonl(kClientIP); out += 4; // destination IP
+
+ // TCP
+ u8* resp_tcpheader = out;
+ *(u16*)out = htons(sock->DestPort); out += 2; // source port
+ *(u16*)out = htons(sock->SourcePort); out += 2; // destination port
+ *(u32*)out = htonl(sock->SeqNum); out += 4; // seq number
+ *(u32*)out = htonl(sock->AckNum); out += 4; // ack seq number
+ *(u16*)out = htons(0x5018); out += 2; // flags (ACK, PSH)
+ *(u16*)out = htons(0x7000); out += 2; // window size (uuuh)
+ *(u16*)out = 0; out += 2; // checksum
+ *(u16*)out = 0; out += 2; // urgent pointer
+
+ memcpy(out, data, len); out += len;
+
+ u32 framelen = (u32)(out - &resp[0]);
+ if (framelen & 1) { *out++ = 0; framelen++; }
+ FinishTCPFrame(resp, framelen);
+
+ // TODO: if there is already a packet queued, this will overwrite it
+ // that being said, this will only happen during DHCP setup, so probably
+ // not a big deal
+
+ PacketLen = framelen;
+ memcpy(PacketBuffer, resp, PacketLen);
+ RXNum = 1;
+}
+
void HandleTCPFrame(u8* data, int len)
{
u8* ipheader = &data[0xE];
@@ -715,6 +649,7 @@ void HandleTCPFrame(u8* data, int len)
sock->DestPort = dstport;
sock->SourcePort = srcport;
sock->SeqNum = 0x13370000;
+ sock->AckNum = 0;
// open backend socket
if (!sock->Backend)
@@ -725,7 +660,8 @@ void HandleTCPFrame(u8* data, int len)
struct sockaddr_in conn_addr;
memset(&conn_addr, 0, sizeof(conn_addr));
conn_addr.sin_family = AF_INET;
- conn_addr.sin_addr.S_un.S_addr = *(u32*)&ipheader[16];
+ //conn_addr.sin_addr.S_un.S_addr = *(u32*)&ipheader[16];
+ memcpy(&conn_addr.sin_addr, &ipheader[16], 4);
conn_addr.sin_port = htons(dstport);
if (connect(sock->Backend, (sockaddr*)&conn_addr, sizeof(conn_addr)) == SOCKET_ERROR)
{
@@ -763,7 +699,13 @@ void HandleTCPFrame(u8* data, int len)
{
u8* tcpdata = &tcpheader[tcpheaderlen];
- printf("TCP: forwarding %d bytes\n", tcpdatalen);
+ // TODO: check those
+ u32 seqnum = ntohl(*(u32*)&tcpheader[4]);
+ u32 acknum = ntohl(*(u32*)&tcpheader[8]);
+ sock->SeqNum = acknum;
+ sock->AckNum = seqnum + tcpdatalen;
+
+ printf("TCP: socket %d sending %d bytes\n", sockid, tcpdatalen);
send(sock->Backend, (char*)tcpdata, tcpdatalen, 0);
}
@@ -898,7 +840,32 @@ int RecvPacket(u8* data)
RXNum = 0;
}
- // TODO: check sockets
+ for (int i = 0; i < (sizeof(TCPSocketList)/sizeof(TCPSocket)); i++)
+ {
+ TCPSocket* sock = &TCPSocketList[i];
+ if (sock->Status != 1) continue;
+
+ fd_set fd;
+ struct timeval tv;
+
+ FD_ZERO(&fd);
+ FD_SET(sock->Backend, &fd);
+ tv.tv_sec = 0;
+ tv.tv_usec = 0;
+
+ if (!select(sock->Backend+1, &fd, 0, 0, &tv))
+ {
+ continue;
+ }
+
+ u8 recvbuf[1024];
+ int recvlen = recv(sock->Backend, (char*)recvbuf, 1024, 0);
+ if (recvlen < 1) continue;
+
+ printf("TCP: socket %d receiving %d bytes\n", i, recvlen);
+ TCP_BuildIncomingFrame(sock, recvbuf, recvlen);
+ }
+
return ret;
}