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/* -ed- ============= */
#include <stdio.h>
#if 0
#define HI_TECH_C
#endif
#define SCN 0x01
#define SCA 0x02
typedef enum
{
FALSE,
TRUE
}
BOOL;
typedef unsigned char BYTE;
typedef unsigned short WORD;
typedef unsigned long DWORD;
typedef union
{
unsigned long lw;
BYTE b[4];
}
LWORD;
enum
{
IPCP_OPT_ADDR
};
enum
{
EVENT_RCR_ERR,
EVENT_RCR_OK,
EVENT_RCN,
EVENT_dummy
};
static enum
{
PPP_CFG_REQ,
PPP_ECHO_REQ,
PPP_OPENED,
PPP_ECHO_REP,
PPP_IPCP,
PPP_CFG_NAK,
PPP_CFG_ACK,
PPP_dummy
}
ppp_code;
static BYTE lcp_state;
static BYTE net_rxin;
static BYTE rxout;
static BYTE ppp_rxid;
static BYTE ppp_pcol;
static LWORD hostip;
static LWORD myip;
static BOOL ipcp_action;
static BYTE get_byte (BYTE * p)
{
return *p;
}
static void put_byte (int val)
{
putchar (val);
}
static void copy_rx_tx (int val) // Echo the data
{
putchar (val);
}
static void send_ppp (BYTE ppp, int id, int a)
{
printf ("send_ppp (%d, %d, %d)\n", ppp, id, a);
}
static void ipcp_event_handler (BYTE a)
{
printf ("ipcp_event_handler(%d)\n", a);
}
BOOL match_byte (BYTE a)
{
return a == 0xFF;
}
/* ================== */
/* Get an incoming lword value, return 0 if end of message */
/////////////////////////////////
//Fonction avec problemes///
////////////////////////////////
// j'es mi plein de ////////////// lorsque ces fonctions sont appelées
BOOL get_lword (LWORD * lwp)
{
#ifdef HI_TECH_C
BYTE n = 4, b;
while (n && get_byte (&b))
lwp->b[--n] = b;
return (n == 0);
#else
if (get_byte (&lwp->b[3]) && get_byte (&lwp->b[2]) &&
get_byte (&lwp->b[1]) && get_byte (&lwp->b[0]))
return (1);
return (0);
#endif
}
/* Put a longword in the network buffer, then add to checksum */
void put_lword (LWORD * lwp)
{
put_byte (lwp->b[3]);
put_byte (lwp->b[2]);
put_byte (lwp->b[1]);
put_byte (lwp->b[0]);
}
/* --------------------------------------------------------------------- */
/////////////////////////
//fonction principales//
/////////////////////////
/* Rx handler for Link Control Protocol */
void lcp_rx_handler (void)
{
LWORD lw;
if (ppp_code == PPP_CFG_REQ) // LCP Config request?
{ // Check option list
}
else if (ppp_code == PPP_ECHO_REQ) // LCP echo request?
{
if ((lcp_state & 0xf) == PPP_OPENED && get_lword (&lw)) /////////////////////////////
{ // Get magic num
lw.lw++; // Return magic num + 1
put_lword (&lw); ///////////////////////////////////////////////////////////
copy_rx_tx (net_rxin - rxout); // Echo the data
send_ppp (PPP_ECHO_REP, ppp_rxid, 1);
} // Others to state machine..
}
}
/* Rx handler for Internet Protocol Control Protocol */
void ipcp_rx_handler (void)
{
BYTE opt, optlen;
BYTE rejects = 0;
ppp_pcol = PPP_IPCP;
if (ppp_code == PPP_CFG_REQ) // IPCP config request?
{ // Check option list
while (get_byte (&opt) && get_byte (&optlen) && optlen >= 2)
{
if (opt == IPCP_OPT_ADDR && optlen == 6) // IP address option?
get_lword (&hostip); // (will be accepted) /////////////////////////////////
else
{
}
}
if (rejects) // If any rejected options..
{
}
else if (!hostip.lw) // If null IP address
{
hostip.lw = myip.lw + 1; // ..give host my IP addr + 1
ipcp_event_handler (EVENT_RCR_ERR); // (for want of anthing else)
if (ipcp_action & SCN)
{ // If OK to NAK, do so
put_byte (IPCP_OPT_ADDR);
put_byte (6);
put_lword (&hostip); // ..with new address as hint ///////////////////////////////////////////
send_ppp (PPP_CFG_NAK, ppp_rxid, 1);
}
}
else // If options OK..
{
ipcp_event_handler (EVENT_RCR_OK);
if (ipcp_action & SCA) // ..and OK to send, do so
{
put_byte (IPCP_OPT_ADDR);
put_byte (6);
put_lword (&hostip); ////////////////////////////////////////////////
send_ppp (PPP_CFG_ACK, ppp_rxid, 1);
}
}
}
else if (ppp_code == PPP_CFG_NAK) // If NAK received..
{ // ..and IP address hint..
if (match_byte (IPCP_OPT_ADDR) && match_byte (6))
get_lword (&myip); // ..use it for my address /////////////////////
ipcp_event_handler (EVENT_RCN);
}
} |
