mirror of
https://github.com/lwip-tcpip/lwip.git
synced 2024-11-05 08:28:32 +00:00
PPP, added PPP documentation
This commit is contained in:
Sylvain Rochet
parent
6b4db944dd
commit
e5f38bf391
355
doc/ppp.txt
Normal file
355
doc/ppp.txt
Normal file
@ -0,0 +1,355 @@
|
||||
PPP interface for lwIP
|
||||
|
||||
Author: Sylvain Rochet
|
||||
|
||||
Table of Contents:
|
||||
|
||||
1 - Supported PPP protocols and features
|
||||
2 - Raw API PPP example for all protocols
|
||||
3 - PPPoS input path (raw API and thread safe API)
|
||||
4 - Thread safe PPP API (PPPAPI)
|
||||
5 - Upgrading from lwIP <= 1.4.x to lwIP >= 1.5.x
|
||||
|
||||
|
||||
|
||||
1 Supported PPP protocols and features
|
||||
======================================
|
||||
|
||||
Supported Low level protocols:
|
||||
* PPP over serial using HDLC-like framing, such as wired dialup modems
|
||||
or mobile telecommunications GPRS/EDGE/UMTS/HSPA+/LTE modems
|
||||
* PPP over Ethernet, such as xDSL modems
|
||||
* PPP over L2TP (Layer 2 Tunneling Protocol) LAC (L2TP Access Concentrator),
|
||||
IP tunnel over UDP, such as VPN access
|
||||
|
||||
Supported auth protocols:
|
||||
* PAP, Password Authentication Protocol
|
||||
* CHAP, Challenge-Handshake Authentication Protocol, also known as CHAP-MD5
|
||||
* MSCHAPv1, Microsoft version of CHAP, version 1
|
||||
* MSCHAPv2, Microsoft version of CHAP, version 2
|
||||
* EAP, Extensible Authentication Protocol
|
||||
|
||||
Supported address protocols:
|
||||
* IPCP, IP Control Protocol, IPv4 addresses negotiation
|
||||
* IP6CP, IPv6 Control Protocol, IPv6 link-local addresses negotiation
|
||||
|
||||
Supported compression or miscellaneous protocols, for serial links only:
|
||||
* PFC, Protocol Field Compression
|
||||
* ACFC, Address-and-Control-Field-Compression
|
||||
* ACCM, Asynchronous-Control-Character-Map
|
||||
* VJ, Van Jacobson TCP/IP Header Compression
|
||||
|
||||
|
||||
|
||||
2 Raw API PPP example for all protocols
|
||||
=======================================
|
||||
|
||||
As usual, raw API for lwIP means the lightweight API which *MUST* only be used
|
||||
for NO_SYS=1 systems or called inside lwIP core thread for NO_SYS=0 systems.
|
||||
|
||||
/*
|
||||
* Globals
|
||||
* =======
|
||||
*/
|
||||
|
||||
/* The PPP control block */
|
||||
ppp_pcb *ppp;
|
||||
|
||||
/* The PPP IP interface */
|
||||
struct netif ppp_netif;
|
||||
|
||||
|
||||
/*
|
||||
* PPP status callback
|
||||
* ===================
|
||||
*
|
||||
* PPP status callback is called on PPP status change (up, down, …) from lwIP
|
||||
* core thread
|
||||
*/
|
||||
|
||||
/* PPP status callback example */
|
||||
static void status_cb(ppp_pcb *pcb, int err_code, void *ctx) {
|
||||
LWIP_UNUSED_ARG(ctx);
|
||||
|
||||
switch(err_code) {
|
||||
case PPPERR_NONE: { /* No error. */
|
||||
struct ppp_addrs *ppp_addrs = ppp_addrs(pcb);
|
||||
printf("status_cb: PPPERR_NONE\n");
|
||||
printf(" our_ipaddr = %s\n", ip_ntoa(&ppp_addrs->our_ipaddr));
|
||||
printf(" his_ipaddr = %s\n", ip_ntoa(&ppp_addrs->his_ipaddr));
|
||||
printf(" netmask = %s\n", ip_ntoa(&ppp_addrs->netmask));
|
||||
printf(" dns1 = %s\n", ip_ntoa(&ppp_addrs->dns1));
|
||||
printf(" dns2 = %s\n", ip_ntoa(&ppp_addrs->dns2));
|
||||
#if PPP_IPV6_SUPPORT
|
||||
printf(" our6_ipaddr = %s\n", ip6addr_ntoa(&ppp_addrs->our6_ipaddr));
|
||||
printf(" his6_ipaddr = %s\n", ip6addr_ntoa(&ppp_addrs->his6_ipaddr));
|
||||
#endif /* PPP_IPV6_SUPPORT */
|
||||
break;
|
||||
}
|
||||
case PPPERR_PARAM: {
|
||||
printf("status_cb: Invalid parameter\n");
|
||||
break;
|
||||
}
|
||||
case PPPERR_OPEN: {
|
||||
printf("status_cb: Unable to open PPP session\n");
|
||||
break;
|
||||
}
|
||||
case PPPERR_DEVICE: {
|
||||
printf("status_cb: Invalid I/O device for PPP\n");
|
||||
break;
|
||||
}
|
||||
case PPPERR_ALLOC: {
|
||||
printf("status_cb: Unable to allocate resources\n");
|
||||
break;
|
||||
}
|
||||
case PPPERR_USER: {
|
||||
printf("status_cb: User interrupt\n");
|
||||
break;
|
||||
}
|
||||
case PPPERR_CONNECT: {
|
||||
printf("status_cb: Connection lost\n");
|
||||
break;
|
||||
}
|
||||
case PPPERR_AUTHFAIL: {
|
||||
printf("status_cb: Failed authentication challenge\n");
|
||||
break;
|
||||
}
|
||||
case PPPERR_PROTOCOL: {
|
||||
printf("status_cb: Failed to meet protocol\n");
|
||||
break;
|
||||
}
|
||||
case PPPERR_PEERDEAD: {
|
||||
printf("status_cb: Connection timeout\n");
|
||||
break;
|
||||
}
|
||||
case PPPERR_IDLETIMEOUT: {
|
||||
printf("status_cb: Idle Timeout\n");
|
||||
break;
|
||||
}
|
||||
case PPPERR_CONNECTTIME: {
|
||||
printf("status_cb: Max connect time reached\n");
|
||||
break;
|
||||
}
|
||||
case PPPERR_LOOPBACK: {
|
||||
printf("status_cb: Loopback detected\n");
|
||||
break;
|
||||
}
|
||||
default: {
|
||||
printf("status_cb: unknown err code %d\n", err_code);
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* This should be in the switch case, this is put outside of the switch
|
||||
* case for example readability.
|
||||
*/
|
||||
|
||||
if (err_code == PPPERR_NONE) {
|
||||
return;
|
||||
}
|
||||
|
||||
/* ppp_close() was previously called, don't reconnect */
|
||||
if (err_code == PPPERR_USER) {
|
||||
/* ppp_free(); -- can be called here */
|
||||
return;
|
||||
}
|
||||
|
||||
/*
|
||||
* Try to reconnect in 30 seconds, if you need a modem chatscript you have
|
||||
* to do a much better signaling here ;-)
|
||||
*/
|
||||
ppp_open(pcb, 30);
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* Creating a new PPPoS session
|
||||
* ============================
|
||||
*
|
||||
* In lwIP, PPPoS is not PPPoSONET, PPPoS is PPPoSerial in lwIP.
|
||||
*/
|
||||
|
||||
#include "netif/ppp/pppos.h"
|
||||
|
||||
/*
|
||||
* Create a new PPPoS interface
|
||||
*
|
||||
* ppp_netif, netif to use for this PPP link, i.e. PPP IP interface
|
||||
* ppp_sio, handler to your SIO port (see include/lwip/sio.h)
|
||||
* status_cb, PPP status callback, called on PPP status change (up, down, …)
|
||||
* ctx_cb, optional user-provided callback context pointer
|
||||
*/
|
||||
ppp = pppos_create(&ppp_netif,
|
||||
ppp_sio,
|
||||
status_cb, ctx_cb);
|
||||
|
||||
|
||||
/*
|
||||
* Creating a new PPPoE session
|
||||
* ============================
|
||||
*/
|
||||
|
||||
#include "netif/ppp/pppoe.h"
|
||||
|
||||
/*
|
||||
* Create a new PPPoE interface
|
||||
*
|
||||
* ppp_netif, netif to use for this PPP link, i.e. PPP IP interface
|
||||
* ethif, already existing and setup Ethernet interface to use
|
||||
* service_name, PPPoE service name discriminator (not supported yet)
|
||||
* concentrator_name, PPPoE concentrator name discriminator (not supported yet)
|
||||
* status_cb, PPP status callback, called on PPP status change (up, down, …)
|
||||
* ctx_cb, optional user-provided callback context pointer
|
||||
*/
|
||||
ppp = pppoe_create(&ppp_netif,
|
||||
ðif,
|
||||
service_name, concentrator_name,
|
||||
status_cb, ctx_cb);
|
||||
|
||||
|
||||
/*
|
||||
* Creating a new PPPoL2TP session
|
||||
* ===============================
|
||||
*/
|
||||
|
||||
#include "netif/ppp/pppol2tp.h"
|
||||
|
||||
/*
|
||||
* Create a new PPPoL2TP interface
|
||||
*
|
||||
* ppp_netif, netif to use for this PPP link, i.e. PPP IP interface
|
||||
* netif, optional already existing and setup output netif, necessary if you
|
||||
* want to set this interface as default route to settle the chicken
|
||||
* and egg problem with VPN links
|
||||
* ipaddr, IP to connect to
|
||||
* port, UDP port to connect to (usually 1701)
|
||||
* secret, L2TP secret to use
|
||||
* secret_len, size in bytes of the L2TP secret
|
||||
* status_cb, PPP status callback, called on PPP status change (up, down, …)
|
||||
* ctx_cb, optional user-provided callback context pointer
|
||||
*/
|
||||
ppp = pppol2tp_create(&ppp_netif,
|
||||
struct netif *netif, ip_addr_t *ipaddr, u16_t port,
|
||||
u8_t *secret, u8_t secret_len,
|
||||
ppp_link_status_cb_fn link_status_cb, void *ctx_cb);
|
||||
|
||||
|
||||
/*
|
||||
* PPP link configuration
|
||||
* ======================
|
||||
*/
|
||||
|
||||
/* Auth configuration, this is pretty self-explanatory */
|
||||
ppp_set_auth(ppp, PPPAUTHTYPE_ANY, "login", "password");
|
||||
|
||||
/* Set this interface as default route */
|
||||
ppp_set_default(ppp);
|
||||
|
||||
|
||||
/*
|
||||
* Initiate PPP connection
|
||||
* =======================
|
||||
*/
|
||||
|
||||
/*
|
||||
* Initiate PPP negotiation, without waiting (holdoff=0), can only be called
|
||||
* if PPP session is in the dead state (i.e. disconnected).
|
||||
*/
|
||||
ppp_open(ppp, 0);
|
||||
|
||||
|
||||
/*
|
||||
* Closing PPP connection
|
||||
* ======================
|
||||
*/
|
||||
|
||||
/* You can call this function anytime */
|
||||
ppp_close(ppp);
|
||||
/*
|
||||
* Then you must wait your status_cb() to be called, it may takes from a few
|
||||
* seconds to several tens of seconds depending on the current PPP state.
|
||||
*/
|
||||
|
||||
/*
|
||||
* Freeing a PPP connection
|
||||
* ========================
|
||||
*/
|
||||
|
||||
/*
|
||||
* Free the PPP control block, can only be called if PPP session is in the
|
||||
* dead state (i.e. disconnected). You need to call ppp_close() before.
|
||||
*/
|
||||
ppp_free(ppp);
|
||||
|
||||
|
||||
|
||||
3 PPPoS input path (raw API and thread safe API)
|
||||
================================================
|
||||
|
||||
PPPoS require a serial I/O SIO port (see include/lwip/sio.h). Received data
|
||||
on serial port should be sent to lwIP using the pppos_input() function.
|
||||
|
||||
This function is not thread-safe by default, setting PPP_INPROC_MULTITHREADED
|
||||
to a true value in your lwipopts.h file makes pppos_input() thread safe.
|
||||
|
||||
/*
|
||||
* Fonction to call for received data
|
||||
*
|
||||
* ppp, PPP control block
|
||||
* buffer, input buffer
|
||||
* buffer_len, buffer length in bytes
|
||||
*/
|
||||
void pppos_input(ppp, buffer, buffer_len);
|
||||
|
||||
|
||||
|
||||
4 Thread safe PPP API (PPPAPI)
|
||||
==============================
|
||||
|
||||
There is a thread safe API for all corresponding ppp_* functions, you have to
|
||||
enable LWIP_PPP_API in your lwipopts.h file, then see include/lwip/pppapi.h,
|
||||
this is actually pretty obvious.
|
||||
|
||||
|
||||
|
||||
5 Upgrading from lwIP <= 1.4.x to lwIP >= 1.5.x
|
||||
===============================================
|
||||
|
||||
PPP API was fully reworked between 1.4.x and 1.5.x releases. However porting
|
||||
from previous lwIP version is pretty easy:
|
||||
|
||||
* Previous PPP API used an integer to identify PPP sessions, we are now
|
||||
using ppp_pcb* control block, therefore all functions changed from "int ppp"
|
||||
to "ppp_pcb *ppp"
|
||||
|
||||
* struct netif was moved outside the PPP structure, you have to provide a netif
|
||||
for PPP interface in pppoX_create() functions
|
||||
|
||||
* PPP session are not started automatically after you created them anymore,
|
||||
you have to call ppp_open(), this way you can configure the session before
|
||||
starting it.
|
||||
|
||||
* Previous PPP API used CamelCase, we are now using snake_case.
|
||||
|
||||
* Previous PPP API mixed PPPoS and PPPoE calls, this isn't the case anymore,
|
||||
PPPoS functions are now prefixed pppos_ and PPPoE functions are now prefixed
|
||||
pppoe_, common functions are now prefixed ppp_.
|
||||
|
||||
* New PPPERR_ error codes added, check you have all of them in your status
|
||||
callback function
|
||||
|
||||
* Only the following include files should now be used in user application:
|
||||
#include "lwip/pppapi.h"
|
||||
#include "netif/ppp/pppos.h"
|
||||
#include "netif/ppp/pppoe.h"
|
||||
#include "netif/ppp/pppol2tp.h"
|
||||
|
||||
Functions from ppp.h can be used, but you don't need to include this header
|
||||
file as it is already included by above header files.
|
||||
|
||||
* PPP_INPROC_OWNTHREAD was broken by design and was removed, you have to create
|
||||
your own rx thread
|
||||
|
||||
* If you used tcpip_callback_with_block() on ppp_ functions you may wish to use
|
||||
the PPPAPI API instead.
|
||||
Loading…
Reference in New Issue
Block a user