static void send_telnet_cmd(uchar cmd, uchar opt)
{
char buf[16];
if(cmd<TELNET_WILL) {
if(debug_telnet)
lprintf(LOG_INFO,"TX Telnet command: %s"
,telnet_cmd_desc(cmd));
sprintf(buf,"%c%c",TELNET_IAC,cmd);
sendsocket(sock,buf,2);
} else {
if(debug_telnet)
lprintf(LOG_INFO,"TX Telnet command: %s %s"
,telnet_cmd_desc(cmd), telnet_opt_desc(opt));
sprintf(buf,"%c%c%c",TELNET_IAC,cmd,opt);
sendsocket(sock,buf,3);
}
}
void send_telnet_cmd(SOCKET sock, uchar cmd, uchar opt)
{
uchar buf[3];
buf[0]=TELNET_IAC;
buf[1]=cmd;
buf[2]=opt;
if(debug_telnet)
lprintf(LOG_DEBUG,"Sending telnet command: %s %s"
,telnet_cmd_desc(buf[1]),telnet_opt_desc(buf[2]));
if(sendsocket(sock,buf,sizeof(buf))!=sizeof(buf) && debug_telnet)
lprintf(LOG_ERR,"FAILED");
}
BYTE* telnet_interpret(BYTE* inbuf, int inlen, BYTE* outbuf, int *outlen)
{
BYTE command;
BYTE option;
BYTE* first_iac;
int i;
if(inlen<1) {
*outlen=0;
return(inbuf); /* no length? No interpretation */
}
first_iac=(BYTE*)memchr(inbuf, TELNET_IAC, inlen);
if(!telnet_cmdlen && first_iac==NULL) {
*outlen=inlen;
return(inbuf); /* no interpretation needed */
}
if(first_iac!=NULL) {
*outlen=first_iac-inbuf;
memcpy(outbuf, inbuf, *outlen);
} else
*outlen=0;
for(i=*outlen;i<inlen;i++) {
if(inbuf[i]==TELNET_IAC && telnet_cmdlen==1) { /* escaped 255 */
telnet_cmdlen=0;
outbuf[(*outlen)++]=TELNET_IAC;
continue;
}
if(inbuf[i]==TELNET_IAC || telnet_cmdlen) {
if(telnet_cmdlen<sizeof(telnet_cmd))
telnet_cmd[telnet_cmdlen++]=inbuf[i];
command = telnet_cmd[1];
option = telnet_cmd[2];
if(telnet_cmdlen>=2 && command==TELNET_SB) {
if(inbuf[i]==TELNET_SE
&& telnet_cmd[telnet_cmdlen-2]==TELNET_IAC) {
if(debug_telnet)
lprintf(LOG_INFO,"RX Telnet sub-negotiation command: %s"
,telnet_opt_desc(option));
/* sub-option terminated */
if(option==TELNET_TERM_TYPE && telnet_cmd[3]==TELNET_TERM_SEND) {
BYTE buf[32];
int len=sprintf(buf,"%c%c%c%c%s%c%c"
,TELNET_IAC,TELNET_SB
,TELNET_TERM_TYPE,TELNET_TERM_IS
,termtype
,TELNET_IAC,TELNET_SE);
if(debug_telnet)
lprintf(LOG_INFO,"TX Telnet command: Terminal Type is %s", termtype);
sendsocket(sock,buf,len);
/* request_telnet_opt(TELNET_WILL, TELNET_TERM_SPEED); */
} else if(option==TELNET_TERM_SPEED && telnet_cmd[3]==TELNET_TERM_SEND) {
BYTE buf[32];
int len=sprintf(buf,"%c%c%c%c%s%c%c"
,TELNET_IAC,TELNET_SB
,TELNET_TERM_SPEED,TELNET_TERM_IS
,termspeed
,TELNET_IAC,TELNET_SE);
if(debug_telnet)
lprintf(LOG_INFO,"TX Telnet command: Terminal Speed is %s", termspeed);
sendsocket(sock,buf,len);
}
telnet_cmdlen=0;
}
}
else if(telnet_cmdlen==2 && inbuf[i]<TELNET_WILL) {
telnet_cmdlen=0;
}
else if(telnet_cmdlen>=3) { /* telnet option negotiation */
if(debug_telnet)
lprintf(LOG_INFO,"RX Telnet command: %s %s"
,telnet_cmd_desc(command),telnet_opt_desc(option));
if(command==TELNET_DO || command==TELNET_DONT) { /* local options */
if(telnet_local_option[option]!=command) {
switch(option) {
case TELNET_BINARY_TX:
case TELNET_ECHO:
case TELNET_TERM_TYPE:
case TELNET_TERM_SPEED:
case TELNET_SUP_GA:
telnet_local_option[option]=command;
send_telnet_cmd(telnet_opt_ack(command),option);
break;
case TELNET_SEND_LOCATION:
if(command==TELNET_DO) {
BYTE buf[128];
int len=safe_snprintf(buf,sizeof(buf),"%c%c%c%s %s%c%c"
,TELNET_IAC,TELNET_SB
,TELNET_SEND_LOCATION
,cid_number, cid_name
,TELNET_IAC,TELNET_SE);
if(debug_telnet)
lprintf(LOG_INFO,"TX Telnet command: Location is %s %s", cid_number, cid_name);
sendsocket(sock,buf,len);
} else
send_telnet_cmd(telnet_opt_ack(command),option);
break;
default: /* unsupported local options */
if(command==TELNET_DO) /* NAK */
send_telnet_cmd(telnet_opt_nak(command),option);
break;
}
}
} else { /* WILL/WONT (remote options) */
if(telnet_remote_option[option]!=command) {
switch(option) {
case TELNET_BINARY_TX:
case TELNET_ECHO:
case TELNET_TERM_TYPE:
case TELNET_SUP_GA:
telnet_remote_option[option]=command;
send_telnet_cmd(telnet_opt_ack(command),option);
break;
default: /* unsupported remote options */
if(command==TELNET_WILL) /* NAK */
send_telnet_cmd(telnet_opt_nak(command),option);
break;
}
}
}
telnet_cmdlen=0;
}
} else
outbuf[(*outlen)++]=inbuf[i];
}
return(outbuf);
}
int recv_byte(void* unused, unsigned timeout)
{
int i;
long t;
uchar ch;
fd_set socket_set;
time_t end;
struct timeval tv;
static uchar telnet_cmd;
static int telnet_cmdlen;
end=msclock()+(timeout*MSCLOCKS_PER_SEC);
while(!terminate) {
FD_ZERO(&socket_set);
#ifdef __unix__
if(stdio)
FD_SET(STDIN_FILENO,&socket_set);
else
#endif
FD_SET(sock,&socket_set);
if((t=end-msclock())<0) t=0;
tv.tv_sec=t/MSCLOCKS_PER_SEC;
tv.tv_usec=0;
if((i=select(sock+1,&socket_set,NULL,NULL,&tv))<1) {
if(i==SOCKET_ERROR) {
lprintf(LOG_ERR,"ERROR %d selecting socket", ERROR_VALUE);
}
if(timeout)
lprintf(LOG_WARNING,"Receive timeout (%u seconds)", timeout);
return(NOINP);
}
#ifdef __unix__
if(stdio)
i=read(STDIN_FILENO,&ch,sizeof(ch));
else
#endif
i=recv(sock,&ch,sizeof(ch),0);
if(i!=sizeof(ch)) {
if(i==0) {
lprintf(LOG_WARNING,"Socket Disconnected");
} else
lprintf(LOG_ERR,"recv error %d (%d)",i,ERROR_VALUE);
return(NOINP);
}
if(telnet) {
if(ch==TELNET_IAC) {
#if DEBUG_TELNET
lprintf(LOG_DEBUG,"T<%s> ",telnet_cmd_desc(ch));
#endif
if(telnet_cmdlen==0) {
telnet_cmdlen=1;
continue;
}
if(telnet_cmdlen==1) {
telnet_cmdlen=0;
if(debug_rx)
lprintf(LOG_DEBUG,"RX: %s",chr(TELNET_IAC));
return(TELNET_IAC);
}
}
if(telnet_cmdlen) {
telnet_cmdlen++;
#if DEBUG_TELNET
if(telnet_cmdlen==2)
lprintf(LOG_DEBUG,"T<%s> ",telnet_cmd_desc(ch));
else
lprintf(LOG_DEBUG,"T<%s> ",telnet_opt_desc(ch));
#endif
if(debug_telnet && telnet_cmdlen==3)
lprintf(LOG_DEBUG,"Received telnet command: %s %s"
,telnet_cmd_desc(telnet_cmd),telnet_opt_desc(ch));
if(telnet_cmdlen==3 && telnet_cmd==TELNET_DO)
send_telnet_cmd(sock, TELNET_WILL,ch);
/*
else if(telnet_cmdlen==3 && telnet_cmd==TELNET_WILL)
send_telnet_cmd(sock, TELNET_DO,ch);
*/
telnet_cmd=ch;
if((telnet_cmdlen==2 && ch<TELNET_WILL) || telnet_cmdlen>2) {
telnet_cmdlen=0;
/* Code disabled. Why? ToDo */
/* break; */
}
continue;
}
}
if(debug_rx)
lprintf(LOG_DEBUG,"RX: %s",chr(ch));
return(ch);
}
return(NOINP);
}
