/* fcntl */
int getsockname(int sockfd, struct sockaddr *addr,
socklen_t *addrlen) {
int ret;
struct sock *sk;
socket_idesc_check(sockfd, sk);
if ((addr == NULL) || (addrlen == NULL)
|| (*addrlen <= 0)) {
return SET_ERRNO(EINVAL);
}
ret = kgetsockname(sk, addr, addrlen);
if (ret < 0){
return SET_ERRNO(-ret);
}
return 0;
}
int SendHeader(ksocket_t sock_fd, char *code, void *data)
{
struct sockaddr_in sock_addr;
char buf[256] = {0, };
int len = 0;
int data_count = 0;
short int source;
int saddr;
int i;
kgetsockname(sock_fd, (struct sockaddr *)&sock_addr, &len);
source =sock_addr.sin_port;
saddr = sock_addr.sin_addr.s_addr;
if(strcmp(code, "ini") == 0 || strcmp(code, "alm") == 0)
{
len = sprintf(buf, "%u|%u|%s|", saddr, 1, code);
}
else if(strcmp(code, "exp") == 0)
{
hash *data_table = (hash *)data;
len = sprintf(buf, "%u|%u|%s|", saddr, data_table->count, code);
}
else
{
return -1;
}
for (i = len; i<48; i++)
buf[i] = '-';
data_count = ksend(sock_fd, buf, len+1, 0);
//printk("%s %d\n", buf, data_count);
return data_count;
}
/*this handles the redirection from client to real server*/
void RedirectProc (ksocket_t SockfdFromClnt)
{
struct sockaddr_in RealSrvAddr, stRelayAddr, stTemp1, stTemp;
ksocket_t SockfdRelay;
int on = 1;
char frwd_buffer[BUFFER_SIZE];
int iRBytes, iWBytes, iNWritten, cur, iLen;
unsigned short iClntPort, server_port = 0;
/* kernel thread name*/
sprintf(current->comm, "krelaychld");
allow_signal(SIGKILL);
allow_signal(SIGTERM);
//Copy the values for later use
if ((kgetpeername(SockfdFromClnt, (struct sockaddr *)&stTemp1, &iLen)) < 0)
{
printk (KERN_ERR "kgetpeername() failed\n");
}
iClntPort = stTemp1.sin_port;
/*Create socket*/
if ((SockfdRelay = ksocket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0)
printk(KERN_ERR "Can't create socket.");
memset(&stRelayAddr, 0, sizeof(stRelayAddr));
stRelayAddr.sin_family = AF_INET;
stRelayAddr.sin_addr.s_addr = INADDR_ANY;
stRelayAddr.sin_port = htons(0);
if (ksetsockopt(SockfdRelay, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
{
printk(KERN_ERR "ksetsockopt(SO_REUSEADDR) failed\n");
}
/*Bind our local addrress so that client can send*/
if (kbind(SockfdRelay, (struct sockaddr *) &stRelayAddr, sizeof(stRelayAddr)) < 0)
{
printk(KERN_ERR "Can't bind local address\n");
return;
}
//printk (KERN_ERR "Relay eph port= %d", ntohs(stRelayAddr.sin_port));
//Need to analyze this part@@@@@@@@@
//Store the relay server ephemeral port (Y) in NAT
if (kgetsockname(SockfdRelay, (struct sockaddr *) &stTemp, &iLen) < 0)
{
printk(KERN_ERR "kgetpeername failed\n");
}
// printk (KERN_ERR "Relay eph port= %d", ntohs(stTemp.sin_port));
for (cur = 0; cur <= MAX_TBL_IDX -1; cur++)
{
if (stTbl[cur].iClntPort == iClntPort)
{
stTbl[cur].iRelayPort = stTemp.sin_port;
server_port = stTbl[cur].iClntSrvPort;
break;
}
}
if (0 == server_port)
{
printk (KERN_ERR "Error..Cannot get the server port\n");
kclose (SockfdRelay);
return;
}
//Connect to the Real server
RealSrvAddr.sin_family = PF_INET;
RealSrvAddr.sin_addr.s_addr = (inet_addr(DEF_REAL_IP));
RealSrvAddr.sin_port = server_port;
if (kconnect(SockfdRelay, (struct sockaddr *) &RealSrvAddr, sizeof(RealSrvAddr)) < 0)
{
printk(KERN_ERR "Connect failed\n");
}
for (;;)
{
//printk (KERN_ERR "trying krecv from client\n");
/* Read from Client and send to Real Server */
iRBytes = krecv(SockfdFromClnt, &frwd_buffer, BUFFER_SIZE - 8, MSG_DONTWAIT);
//printk (KERN_ERR "tried krecv = %d\n", iRBytes);
//Client Socket is closed
if (iRBytes == 0)
break;
iWBytes = 0;
iNWritten = 0;
//If some data is there to be read
while (iWBytes != iRBytes && iRBytes > 0)
{
if ((iNWritten = ksend(SockfdRelay, &frwd_buffer + iWBytes , iRBytes-iWBytes, 0)) < 0)
{
printk (KERN_ERR "error occured while writing to receiver\n");
return;
}
iWBytes += iNWritten;
}
//printk (KERN_ERR "trying krecv from real server\n");
/* Read from Real server and write to client */
iRBytes = krecv(SockfdRelay, &frwd_buffer, BUFFER_SIZE - 8, MSG_DONTWAIT);
//printk (KERN_ERR "tried krecv1 = %d\n", iRBytes);
if (iRBytes == 0)
break;
iWBytes = 0;
iNWritten = 0;
while (iWBytes != iRBytes && iRBytes > 0)
{
if ((iNWritten = ksend(SockfdFromClnt, &frwd_buffer + iWBytes , iRBytes-iWBytes, 0)) < 0)
{
printk (KERN_ERR "error occured while writing to receiver\n");
return;
}
iWBytes += iNWritten;
}
//Sleep for sometime
// mdelay (1);
}
(void)kclose(SockfdRelay);
(void)kclose(SockfdFromClnt);
}
