[9fans] ppp patches

[9fans] ppp patches

[Scott Schwartz]

[-- Attachment #1: Type: text/plain, Size: 748 bytes --]

Here's a suggested change to ppp, to provide better support for chat
scripts.  The main idea is to allow tokens like USER, PASSWD, SERVER and
to let factotum hand over the real values, so you can dial completely
non-interactively.

The server flag does double duty: it lets you store multiple ppp
credentials inside factotum and also uses the name of the server as the
phone number to dial.  Absent the -s flag, it tries to deduce from the
name of the chat file or from the telco string.

Examples,
ppp -b 115200 -f -P -u -M telco.chat -p telco!5552222
ppp -b 115200 -f -P -u -M modem.chat -p /dev/eia1 -s 5552222
ppp -b 115200 -f -P -u -M 5552222.chat -p /dev/eia1

This is lightly tested, so let me know if anything goes wrong.


[-- Attachment #2: Type: text/plain, Size: 2614 bytes --]

#include <u.h>
#include <libc.h>
#include <auth.h>
#include "chat.h"

// XXX - make these parameters?
extern int debug;
extern char servername[128];

#define RLEN 1024
#define TIMEOUT (60*1000)

int chat(int ifd, int ofd, char *chatfile)
{
	int chatfd, lineno, nb;
	char *script, *p, *s, response[RLEN];
	Dir *dir;
	UserPasswd *up;

	if ((chatfd = open(chatfile, OREAD)) < 0)
		sysfatal("cannot open %s: %r", chatfile);

	if ((dir = dirfstat(chatfd)) == nil)
		sysfatal("cannot fstat %s: %r",chatfile);

	script = (char *)malloc(dir->length + 1);
	assert(script);

	if ((nb = read(chatfd, script, dir->length)) < 0)
		sysfatal("cannot read chatfile %s: %r", chatfile);
	assert(nb == dir->length);
	script[dir->length] = '\0';
	free(dir);
	close(chatfd);

	p = script;
	lineno = 0;
	while (1) {
		char *_args[3];

		if ((s = strchr(p, '\n')) == nil)
			break;
		*s++ = '\0';
	
		lineno++;

		if (*p == '#') {
			p = s; 
			continue;
		}

		if (tokenize(p, _args, 3) != 2)
			sysfatal("invalid line %d (line expected: 'send' 'expect')", 
					lineno);

		if (strcmp(_args[0], "USER") == 0) {
			up = getuserpass();
			_args[0] = up->user;
		}
		else if (strcmp(_args[0], "PASSWD") == 0) {
			up = getuserpass();
			_args[0] = up->passwd;
		}
		else if (strcmp(_args[0], "SERVER") == 0) {
			_args[0] = servername;
		}
		else if (strcmp(_args[0], "CRNL") == 0) {
			_args[0] = "\r\n";
		}
		else if (strcmp(_args[0], "CR") == 0) {
			_args[0] = "\r";
		}
		else if (strcmp(_args[0], "NL") == 0) {
			_args[0] = "\n";
		}
		else if (strcmp(_args[0], "PAUSE") == 0) {
			sleep(5000);
			_args[0] = "";
		}

		if (debug)
			fprint(2, "sending “%s”, expecting “%s”\n", _args[0], _args[1]);

		if ((nb = write(ofd, _args[0], strlen(_args[0]))) < 0)
			sysfatal("cannot write %ss: %r", _args[0]);
		assert(nb == strlen(_args[0]));

		if (strlen(_args[1]) > 0) {
			char *rp = response;
			char *ep = response+sizeof(response)-1;
			int found = 0;

			alarm(TIMEOUT);
			while ((nb = read(ifd, rp, 1)) >= 0 && rp < ep) {
				if (debug)
					fprint(2, "response %02x %c\n", *rp, *rp);
				rp += nb;
				*rp = 0;
				found = cistrstr(response, _args[1]) != nil;
				if (found) {
					if (debug) fprint(2, "found “%s”\n", response);
					break;
				}
			}
			alarm(0);
			if (nb < 0)
				sysfatal("cannot read response from: %r");
			if (nb == 0)
				sysfatal("eof on input?\n");
			if (!found)
				sysfatal("expected %s, got %s\n", _args[1], response);
		}
		p = s;
	}
	free(script);
	return 1;
}

[-- Attachment #3: Type: text/plain, Size: 72 bytes --]

extern UserPasswd *getuserpass(void);
extern int chat(int,int,char*);

[-- Attachment #4: Type: text/plain, Size: 162 bytes --]

# send expect
ATQ0V1E0M1S0=0 ''
atdt   ''
SERVER ''
CR     'CONNECT'
#
PAUSE ''
CRNL  ':'
#
USER ''
CRNL :
#
PASSWD ''
CRNL   :
#
ppp  ''
CRNL ~

[-- Attachment #5: Type: text/plain, Size: 3411 bytes --]

term% diff /sys/src/cmd/ip/ppp .
Only in .: 8632222.chat
Only in .: chat.c
Only in .: chat.h
diff /sys/src/cmd/ip/ppp/mkfile ./mkfile
11a12
> 	chat.$O\
Only in .: modem.chat
diff /sys/src/cmd/ip/ppp/ppp.c ./ppp.c
8a9
> #include "chat.h"
24a26
> char	servername[PATH];
2512,2572c2514,2519
< 		int chatfd, lineno, nb;
< 		char *buf, *p, *s, response[128];
< 		Dir *dir;
<
< 		if ((chatfd = open(chatfile, OREAD)) < 0)
< 			sysfatal("cannot open %s: %r", chatfile);
<
< 		if ((dir = dirfstat(chatfd)) == nil)
< 			sysfatal("cannot fstat %s: %r",chatfile);
<
< 		buf = (char *)malloc(dir->length + 1);
< 		assert(buf);
<
< 		if ((nb = read(chatfd, buf, dir->length)) < 0)
< 			sysfatal("cannot read chatfile %s: %r", chatfile);
< 		assert(nb == dir->length);
< 		buf[dir->length] = '\0';
< 		free(dir);
< 		close(chatfd);
<
< 		p = buf;
< 		lineno = 0;
< 		while (1) {
< 			char *_args[3];
<
< 			if ((s = strchr(p, '\n')) == nil)
< 				break;
< 			*s++ = '\0';
<
< 			lineno++;
<
< 			if (*p == '#') {
< 				p = s;
< 				continue;
< 			}
<
< 			if (tokenize(p, _args, 3) != 2)
< 				sysfatal("invalid line %d (line expected: 'send' 'expect')",
< 						lineno);
<
< 			if (debug)
< 				print("sending %s, expecting %s\n", _args[0], _args[1]);
<
< 			if ((nb = write(fd, _args[0], strlen(_args[0]))) < 0)
< 				sysfatal("cannot write %ss: %r", _args[0]);
< 			assert(nb == strlen(_args[0]));
<
< 			if (strlen(_args[1]) > 0) {
< 				if ((nb = read(fd, response, sizeof response)) < 0)
< 					sysfatal("cannot read response from: %r");
<
< 				if (debug)
< 					print("response %s\n", response);
<
< 				if (nb == 0)
< 					sysfatal("eof on input?\n");
<
< 				if (cistrstr(response, _args[1]) == nil)
< 					sysfatal("expected %s, got %s\n", _args[1], response);
< 			}
< 			p = s;
---
> 		// Try to deduce the server name from the chatfile name.
> 		if (!*servername) {
> 			char *p;
> 			strecpy(servername, servername+PATH-1, chatfile);
> 			if ((p=strstr(servername, ".chat")))
> 				*p = 0;
2574c2521
< 		free(buf);
---
> 		chat(fd, fd, chatfile);
2576c2523
< 	}
---
> 	};
2632c2579
< 	fprint(2, "usage: ppp [-cCdfPSu] [-b baud] [-k keyspec] [-m mtu] [-p dev] [-s username] [-x netmntpt] [-t modemcmd] [local-addr [remote-addr]]\n");
---
> 	fprint(2, "usage: ppp [-cCdfPSu] [-b baud] [-k keyspec] [-m mtu] [-p dev] [-s servername] [-x netmntpt] [-t modemcmd] [local-addr [remote-addr]]\n");
2706a2654,2656
> 	case 's':
> 		snprint(servername, PATH, "%s", EARGF(usage()));
> 		break;
2743a2694,2701
> 				// If we don't have a user specified server name,
> 				// try to deduce one from the dial string.
> 				if(!*servername) {
> 					char *p = strchr(dev,'!');
> 					snprint(servername, PATH, "%s", p+1);
> 					p = strchr(servername, '!');
> 					if (p) *p = 0;
> 				}
2751a2710
>
2885a2845,2855
> UserPasswd *
> getuserpass()
> {
> 	if (servername[0]==0)
> 		return auth_getuserpasswd(auth_getkey,
> 			"proto=pass service=ppp %s", keyspec);
> 	else
> 		return auth_getuserpasswd(auth_getkey,
> 			"proto=pass service=ppp server=%s %s", servername, keyspec);
> }
>
2893,2895c2863,2864
<
< 	up = auth_getuserpasswd(auth_getkey,"proto=pass service=ppp %s", keyspec);
< 	if(up != nil){
---
>
> 	if((up = getuserpass()) != nil){
2899a2869
>
Only in .: telco.chat
Only in .: try

[-- Attachment #6: Type: text/plain, Size: 100 bytes --]

# send expect
PAUSE ''
CRNL  ':'
#
USER ''
CRNL :
#
PASSWD ''
CRNL   :
#
ppp  ''
CRNL ~

Re: [9fans] ppp patches

[David Presotto]

[-- Attachment #1: Type: text/plain, Size: 311 bytes --]

Actually, I've been trying to get rid of the cat stuff in favor of the
dial/expect, dial/at stuff.  Since this can be embedded in a shell script
with a control structure, I find it a lot more powerful than our chat
scripts.  I'ld rather see the effort go there than turning the chat
scripts into another rc.

[-- Attachment #2: Type: message/rfc822, Size: 9821 bytes --]

[-- Attachment #2.1.1: Type: text/plain, Size: 748 bytes --]

Here's a suggested change to ppp, to provide better support for chat
scripts.  The main idea is to allow tokens like USER, PASSWD, SERVER and
to let factotum hand over the real values, so you can dial completely
non-interactively.

The server flag does double duty: it lets you store multiple ppp
credentials inside factotum and also uses the name of the server as the
phone number to dial.  Absent the -s flag, it tries to deduce from the
name of the chat file or from the telco string.

Examples,
ppp -b 115200 -f -P -u -M telco.chat -p telco!5552222
ppp -b 115200 -f -P -u -M modem.chat -p /dev/eia1 -s 5552222
ppp -b 115200 -f -P -u -M 5552222.chat -p /dev/eia1

This is lightly tested, so let me know if anything goes wrong.


[-- Attachment #2.1.2: Type: text/plain, Size: 2614 bytes --]

#include <u.h>
#include <libc.h>
#include <auth.h>
#include "chat.h"

// XXX - make these parameters?
extern int debug;
extern char servername[128];

#define RLEN 1024
#define TIMEOUT (60*1000)

int chat(int ifd, int ofd, char *chatfile)
{
	int chatfd, lineno, nb;
	char *script, *p, *s, response[RLEN];
	Dir *dir;
	UserPasswd *up;

	if ((chatfd = open(chatfile, OREAD)) < 0)
		sysfatal("cannot open %s: %r", chatfile);

	if ((dir = dirfstat(chatfd)) == nil)
		sysfatal("cannot fstat %s: %r",chatfile);

	script = (char *)malloc(dir->length + 1);
	assert(script);

	if ((nb = read(chatfd, script, dir->length)) < 0)
		sysfatal("cannot read chatfile %s: %r", chatfile);
	assert(nb == dir->length);
	script[dir->length] = '\0';
	free(dir);
	close(chatfd);

	p = script;
	lineno = 0;
	while (1) {
		char *_args[3];

		if ((s = strchr(p, '\n')) == nil)
			break;
		*s++ = '\0';
	
		lineno++;

		if (*p == '#') {
			p = s; 
			continue;
		}

		if (tokenize(p, _args, 3) != 2)
			sysfatal("invalid line %d (line expected: 'send' 'expect')", 
					lineno);

		if (strcmp(_args[0], "USER") == 0) {
			up = getuserpass();
			_args[0] = up->user;
		}
		else if (strcmp(_args[0], "PASSWD") == 0) {
			up = getuserpass();
			_args[0] = up->passwd;
		}
		else if (strcmp(_args[0], "SERVER") == 0) {
			_args[0] = servername;
		}
		else if (strcmp(_args[0], "CRNL") == 0) {
			_args[0] = "\r\n";
		}
		else if (strcmp(_args[0], "CR") == 0) {
			_args[0] = "\r";
		}
		else if (strcmp(_args[0], "NL") == 0) {
			_args[0] = "\n";
		}
		else if (strcmp(_args[0], "PAUSE") == 0) {
			sleep(5000);
			_args[0] = "";
		}

		if (debug)
			fprint(2, "sending “%s”, expecting “%s”\n", _args[0], _args[1]);

		if ((nb = write(ofd, _args[0], strlen(_args[0]))) < 0)
			sysfatal("cannot write %ss: %r", _args[0]);
		assert(nb == strlen(_args[0]));

		if (strlen(_args[1]) > 0) {
			char *rp = response;
			char *ep = response+sizeof(response)-1;
			int found = 0;

			alarm(TIMEOUT);
			while ((nb = read(ifd, rp, 1)) >= 0 && rp < ep) {
				if (debug)
					fprint(2, "response %02x %c\n", *rp, *rp);
				rp += nb;
				*rp = 0;
				found = cistrstr(response, _args[1]) != nil;
				if (found) {
					if (debug) fprint(2, "found “%s”\n", response);
					break;
				}
			}
			alarm(0);
			if (nb < 0)
				sysfatal("cannot read response from: %r");
			if (nb == 0)
				sysfatal("eof on input?\n");
			if (!found)
				sysfatal("expected %s, got %s\n", _args[1], response);
		}
		p = s;
	}
	free(script);
	return 1;
}

[-- Attachment #2.1.3: Type: text/plain, Size: 72 bytes --]

extern UserPasswd *getuserpass(void);
extern int chat(int,int,char*);

[-- Attachment #2.1.4: Type: text/plain, Size: 162 bytes --]

# send expect
ATQ0V1E0M1S0=0 ''
atdt   ''
SERVER ''
CR     'CONNECT'
#
PAUSE ''
CRNL  ':'
#
USER ''
CRNL :
#
PASSWD ''
CRNL   :
#
ppp  ''
CRNL ~

[-- Attachment #2.1.5: Type: text/plain, Size: 3411 bytes --]

term% diff /sys/src/cmd/ip/ppp .
Only in .: 8632222.chat
Only in .: chat.c
Only in .: chat.h
diff /sys/src/cmd/ip/ppp/mkfile ./mkfile
11a12
> 	chat.$O\
Only in .: modem.chat
diff /sys/src/cmd/ip/ppp/ppp.c ./ppp.c
8a9
> #include "chat.h"
24a26
> char	servername[PATH];
2512,2572c2514,2519
< 		int chatfd, lineno, nb;
< 		char *buf, *p, *s, response[128];
< 		Dir *dir;
<
< 		if ((chatfd = open(chatfile, OREAD)) < 0)
< 			sysfatal("cannot open %s: %r", chatfile);
<
< 		if ((dir = dirfstat(chatfd)) == nil)
< 			sysfatal("cannot fstat %s: %r",chatfile);
<
< 		buf = (char *)malloc(dir->length + 1);
< 		assert(buf);
<
< 		if ((nb = read(chatfd, buf, dir->length)) < 0)
< 			sysfatal("cannot read chatfile %s: %r", chatfile);
< 		assert(nb == dir->length);
< 		buf[dir->length] = '\0';
< 		free(dir);
< 		close(chatfd);
<
< 		p = buf;
< 		lineno = 0;
< 		while (1) {
< 			char *_args[3];
<
< 			if ((s = strchr(p, '\n')) == nil)
< 				break;
< 			*s++ = '\0';
<
< 			lineno++;
<
< 			if (*p == '#') {
< 				p = s;
< 				continue;
< 			}
<
< 			if (tokenize(p, _args, 3) != 2)
< 				sysfatal("invalid line %d (line expected: 'send' 'expect')",
< 						lineno);
<
< 			if (debug)
< 				print("sending %s, expecting %s\n", _args[0], _args[1]);
<
< 			if ((nb = write(fd, _args[0], strlen(_args[0]))) < 0)
< 				sysfatal("cannot write %ss: %r", _args[0]);
< 			assert(nb == strlen(_args[0]));
<
< 			if (strlen(_args[1]) > 0) {
< 				if ((nb = read(fd, response, sizeof response)) < 0)
< 					sysfatal("cannot read response from: %r");
<
< 				if (debug)
< 					print("response %s\n", response);
<
< 				if (nb == 0)
< 					sysfatal("eof on input?\n");
<
< 				if (cistrstr(response, _args[1]) == nil)
< 					sysfatal("expected %s, got %s\n", _args[1], response);
< 			}
< 			p = s;
---
> 		// Try to deduce the server name from the chatfile name.
> 		if (!*servername) {
> 			char *p;
> 			strecpy(servername, servername+PATH-1, chatfile);
> 			if ((p=strstr(servername, ".chat")))
> 				*p = 0;
2574c2521
< 		free(buf);
---
> 		chat(fd, fd, chatfile);
2576c2523
< 	}
---
> 	};
2632c2579
< 	fprint(2, "usage: ppp [-cCdfPSu] [-b baud] [-k keyspec] [-m mtu] [-p dev] [-s username] [-x netmntpt] [-t modemcmd] [local-addr [remote-addr]]\n");
---
> 	fprint(2, "usage: ppp [-cCdfPSu] [-b baud] [-k keyspec] [-m mtu] [-p dev] [-s servername] [-x netmntpt] [-t modemcmd] [local-addr [remote-addr]]\n");
2706a2654,2656
> 	case 's':
> 		snprint(servername, PATH, "%s", EARGF(usage()));
> 		break;
2743a2694,2701
> 				// If we don't have a user specified server name,
> 				// try to deduce one from the dial string.
> 				if(!*servername) {
> 					char *p = strchr(dev,'!');
> 					snprint(servername, PATH, "%s", p+1);
> 					p = strchr(servername, '!');
> 					if (p) *p = 0;
> 				}
2751a2710
>
2885a2845,2855
> UserPasswd *
> getuserpass()
> {
> 	if (servername[0]==0)
> 		return auth_getuserpasswd(auth_getkey,
> 			"proto=pass service=ppp %s", keyspec);
> 	else
> 		return auth_getuserpasswd(auth_getkey,
> 			"proto=pass service=ppp server=%s %s", servername, keyspec);
> }
>
2893,2895c2863,2864
<
< 	up = auth_getuserpasswd(auth_getkey,"proto=pass service=ppp %s", keyspec);
< 	if(up != nil){
---
>
> 	if((up = getuserpass()) != nil){
2899a2869
>
Only in .: telco.chat
Only in .: try

[-- Attachment #2.1.6: Type: text/plain, Size: 100 bytes --]

# send expect
PAUSE ''
CRNL  ':'
#
USER ''
CRNL :
#
PASSWD ''
CRNL   :
#
ppp  ''
CRNL ~

Re: [9fans] ppp patches

[Richard Miller]

> Actually, I've been trying to get rid of the cat stuff in favor of the
> dial/expect, dial/at stuff.  Since this can be embedded in a shell script
> with a control structure, I find it a lot more powerful than our chat
> scripts.  I'ld rather see the effort go there than turning the chat
> scripts into another rc.

Rc seems to be a perfectly adequate scripting engine.  Here's the rough
and ready script I used for compuserve.  The command 'cread [-t S] C' copies
from stdin to stdout until character C is encountered or S seconds elapse.
It might be usefully generalised by making C a regular expression, but the
simple form was enough for my scripts.

(A google gropups search shows that I posted this to comp.os.plan9 on 2000-11-14)

#!/bin/rc
fn expect { x=`{cread -t $1 :}; echo got: $x >[1=2]; ~ $x *^$2^*}
fn send   { echo sent: $1 >[1=2]; echo $1 | tr '\12' '\15' }
fn sendq  { echo $1 | tr '\12' '\15' }
fn readuntil { @{ while (x=`{cread -t 60 '
'}) { echo got: $x >[1=2]; if (~ $x *^$1^*) exit () } } }

echo $0 running >[1=2]
send ''
while (! expect 10 ame:) {send ''}
send CIS
if (! expect 10 ID:) exit 'no ID prompt'
send 999999,999/GO:PPPCONNECT
expect 60 GO:
if (! expect 10 ord:) exit 'no password prompt'
sendq '*my*password*'
readuntil 'One moment please'

-- Richard

Re: [9fans] ppp patches

[David Presotto]

I updated sources with /sys/src/cmd/dial/* and /sys/man/1/expect.  It's
a bunch of stuff I've been using for a year to do dialing.  I thought it
was on sources.  Sorry.

For examples, look at /rc/bin/ipconf/*

Re: [9fans] ppp patches

[Scott Schwartz]

Thanks Dave.

Looking that stuff over, I see that it doesn't use use factotum.  But
ip/ppp does!  Why not let factotum do all the prompting for passwords?
Also, the patches I sent use the server= field to distinguish multiple
places you might want to connect to.  I think that's worth having.
It also means that you don't have to prompt for the dial string, because
you can get it from factotum along with the other credentials.

I can't help noticing that the ipconf scripts don't use telco.  I really
like telco, I think it's a really beautiful demonstration of how Plan 9
does something much more cleanly than Unix.  It especially shines when
your ISP has several phone numbers, because you can add telco entries to
ndb and telco will try each phone number until it gets a connection (just
like telnet does with IP numbers.)  But maybe it is all less useful now
that modems are less popular, timeshareing is less popular, and perhaps
people just don't want to pay for an extra process handling the data.

Re: [9fans] ppp patches

[David Presotto]

I'ld love to let factotum do the prompting.  If you use chap or mschap, it already
does.  I'll stick your prompting changes into a dial/whatever routine and the
dial stuff can do it too.  We can't use them at workm, because we use RSA Securid tokens
for passwords

As for the server= field, we can easily pass that in as a parameter that will
get passed to factotum.  I'm not so sure about dialstrings.  They really aren't
part of the security info and, at least in the case of the 3 ISP's I deal with,
are relative to where I'm dialing from.  I'ld rather not stick that all into
my secstore.

I agree about telco, that's why I wrote it.  However, I found that people
here just don't use it, probably for the reason you mentioned.

Thanks, does this sound reasonable to you?

Re: [9fans] ppp patches

[Scott Schwartz]

| As for the server= field, we can easily pass that in as a parameter that will
| get passed to factotum.  I'm not so sure about dialstrings.  They really aren't
| part of the security info and, at least in the case of the 3 ISP's I deal with,
| are relative to where I'm dialing from.  I'ld rather not stick that all into
| my secstore.

Hm.  Ok, I guess.  I'll have to play with the scripts some more and see
how they feel.

| Thanks, does this sound reasonable to you?

Pretty much.