auth.c

vxworks的tcpip协议栈源码

/* auth.c - PPP authentication and phase control */

/* Copyright 1995 Wind River Systems, Inc. */
#include "copyright_wrs.h"

/*
 * Copyright (c) 1993 The Australian National University.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by the Australian National University.  The name of the University
 * may not be used to endorse or promote products derived from this
 * software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Copyright (c) 1989 Carnegie Mellon University.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by Carnegie Mellon University.  The name of the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

/*
modification history
--------------------
01l,14feb97,ms   allow VxSim/Solaris to use 127.x.x.x addresses
01k,30jul95,dzb  fixed to avoid trying to open NULL filenames (SPR #4560).
01j,26jun95,dzb  removed usehostname option.
01i,21jun95,dzb  created pppCryptRtn to unbundled DES encryption.
01h,16jun95,dzb  header file consolidation.
01g,07jun95,dzb  make sure we got neg_chap when we "required" CHAP.
                 made LOG_NOTICE message printed even w/o debug option.
01f,11may95,dzb  added calls to pppSecretLib for VxWorks secrets table.
                 added call to loginUserVerify() for "login" option.
		 re-activated auth_ip_addr() checking.
		 switched lcp_close() calls to go through die().
		 moved WILD defines to auth.h.  removed logged_in and logout().
		 removed checking for attempts at password checking.
01e,05may95,dzb  check for null client/server strings in scan_authfile().
01d,13feb95,dab  added check for debug option in link_terminated().
01c,09feb95,dab  removed the UNIX-centric routine login().
01b,16jan95,dab  reverse params for crypt() call.
01a,21dec94,dab  VxWorks port - first WRS version.
           +dzb  added: path for ppp header files, WRS copyright.
*/

#include "vxWorks.h"
#include "stdio.h"
#include "string.h"
#include "sysLib.h"
#include "taskLib.h"
#include "loginLib.h"
#include "hostLib.h"
#include "sys/types.h"
#include "sys/stat.h"
#include "netinet/in.h"
#include "arpa/inet.h"
#include "pppLib.h"

/* Bits in auth_pending[] */
#define UPAP_WITHPEER	1
#define UPAP_PEER	2
#define CHAP_WITHPEER	4
#define CHAP_PEER	8

/* Prototypes */

static int  null_login __ARGS((int));
static int  get_upap_passwd __ARGS((void));
static int  have_upap_secret __ARGS((void));
static int  have_chap_secret __ARGS((char *, char *));
static int  scan_authfile __ARGS((FILE *, char *, char *, char *,
				  struct wordlist **, char *));
static void free_wordlist __ARGS((struct wordlist *));

FUNCPTR	pppCryptRtn = NULL;	/* PPP cryptographic authentication routine */

/*
 * An Open on LCP has requested a change from Dead to Establish phase.
 * Do what's necessary to bring the physical layer up.
 */
void
link_required(unit)
	int unit;
{
}

/*
 * LCP has terminated the link; go to the Dead phase and take the
 * physical layer down.
 */
void
link_terminated(unit)
	int unit;
{
    ppp_if[unit]->phase = PHASE_DEAD;
    syslog(LOG_NOTICE, "Connection terminated.");
}

/*
 * LCP has gone down; it will either die or try to re-establish.
 */
void
link_down(unit)
    int unit;
{
    ppp_if[unit]->phase = PHASE_TERMINATE;
}

/*
 * The link is established.
 * Proceed to the Dead, Authenticate or Network phase as appropriate.
 */
void
link_established(unit)
	int unit;
{
    int auth;
    lcp_options *wo = &ppp_if[unit]->lcp_wantoptions;
    lcp_options *go = &ppp_if[unit]->lcp_gotoptions;
    lcp_options *ho = &ppp_if[unit]->lcp_hisoptions;

    if (ppp_if[unit]->auth_required && !(go->neg_chap || go->neg_upap)) {
	/*
         * We wanted the peer to authenticate itself, and it refused:
         * treat it as though it authenticated with PAP using a username
         * of "" and a password of "".  If that's not OK, boot it out.
	 *
	 * NB:
	 * Changed this "if" statement to look for requiring CHAP and
	 * not PAP (covered by !wo->neg_upap), so that peer cannot simply
	 * refuse CHAP and get away with it...
	 */
        if (!wo->neg_upap || !null_login(unit)) {
            syslog(LOG_WARNING, "peer refused to authenticate");
	    die(unit, 1);
        }
    }

    ppp_if[unit]->phase = PHASE_AUTHENTICATE;
    auth = 0;
    if (go->neg_chap) {
	ChapAuthPeer(unit, ppp_if[unit]->our_name, go->chap_mdtype);
	auth |= CHAP_PEER;
    } else if (go->neg_upap) {
	upap_authpeer(unit);
	auth |= UPAP_PEER;
    }
    if (ho->neg_chap) {
	ChapAuthWithPeer(unit, ppp_if[unit]->our_name, ho->chap_mdtype);
	auth |= CHAP_WITHPEER;
    } else if (ho->neg_upap) {
	upap_authwithpeer(unit, ppp_if[unit]->user, ppp_if[unit]->passwd);
	auth |= UPAP_WITHPEER;
    }
    ppp_if[unit]->auth_pending = auth;

    if (!auth) {
        ppp_if[unit]->phase = PHASE_NETWORK;
        ipcp_open(unit);
    }
}

/*
 * The peer has failed to authenticate himself using `protocol'.
 */
void
auth_peer_fail(unit, protocol)
    int unit, protocol;
{
    /*
     * Authentication failure: take the link down
     */
    die(unit, 1);
}

/*
 * The peer has been successfully authenticated using `protocol'.
 */
void
auth_peer_success(unit, protocol)
    int unit, protocol;
{
    int bit;

    switch (protocol) {
    case CHAP:
	bit = CHAP_PEER;
	break;
    case UPAP:
	bit = UPAP_PEER;
	break;
    default:
	syslog(LOG_WARNING, "auth_peer_success: unknown protocol %x",
               protocol);
	return;
    }

    /*
     * If there is no more authentication still to be done,
     * proceed to the network phase.
     */
    if ((ppp_if[unit]->auth_pending &= ~bit) == 0) {
        ppp_if[unit]->phase = PHASE_NETWORK;
	ipcp_open(unit);
    }
}

/*
 * We have failed to authenticate ourselves to the peer using `protocol'.
 */
void
auth_withpeer_fail(unit, protocol)
    int unit, protocol;
{
    /*
     * We've failed to authenticate ourselves to our peer.
     * He'll probably take the link down, and there's not much
     * we can do except wait for that.
     */
}

/*
 * We have successfully authenticated ourselves with the peer using `protocol'.
 */
void
auth_withpeer_success(unit, protocol)
    int unit, protocol;
{
    int bit;

    switch (protocol) {
    case CHAP:
	bit = CHAP_WITHPEER;
	break;
    case UPAP:
	bit = UPAP_WITHPEER;
	break;
    default:
	syslog(LOG_WARNING, "auth_peer_success: unknown protocol %x",
               protocol);
        bit = 0;
    }

    /*
     * If there is no more authentication still being done,
     * proceed to the network phase.
     */
    if ((ppp_if[unit]->auth_pending &= ~bit) == 0) {
        ppp_if[unit]->phase = PHASE_NETWORK;
	ipcp_open(unit);
    }
}

/*
 * check_auth_options - called to check authentication options.
 */
void
check_auth_options()
{
    lcp_options *wo = &ppp_if[ppp_unit]->lcp_wantoptions;
    lcp_options *ao = &ppp_if[ppp_unit]->lcp_allowoptions;

    /* Default our_name to hostname, and user to our_name */
    if (ppp_if[ppp_unit]->our_name[0] == 0)
	strcpy(ppp_if[ppp_unit]->our_name, ppp_if[ppp_unit]->hostname);
    if (ppp_if[ppp_unit]->user[0] == 0)
	strcpy(ppp_if[ppp_unit]->user, ppp_if[ppp_unit]->our_name);

    /* If authentication is required, ask peer for CHAP or PAP. */
    if (ppp_if[ppp_unit]->auth_required && !wo->neg_chap && !wo->neg_upap) {
	wo->neg_chap = 1;
	wo->neg_upap = 1;
    }

    /*
     * Check whether we have appropriate secrets to use
     * to authenticate ourselves and/or the peer.
     */
    if (ao->neg_upap && ppp_if[ppp_unit]->passwd[0] == 0 && !get_upap_passwd())
	ao->neg_upap = 0;
    if (wo->neg_upap && !ppp_if[ppp_unit]->uselogin && !have_upap_secret())
	wo->neg_upap = 0;
    if (ao->neg_chap && !have_chap_secret(ppp_if[ppp_unit]->our_name, ppp_if[ppp_unit]->remote_name))
	ao->neg_chap = 0;
    if (wo->neg_chap && !have_chap_secret(ppp_if[ppp_unit]->remote_name, ppp_if[ppp_unit]->our_name))
	wo->neg_chap = 0;

    if (ppp_if[ppp_unit]->auth_required && !wo->neg_chap && !wo->neg_upap) {
	syslog(LOG_ERR, "peer authentication required but no authentication files accessible");
	die(ppp_unit, 1);
    }

}


/*
 * check_passwd - Check the user name and passwd against the PAP secrets
 * file.  If requested, also check against the system password database,
 * and login the user if OK.
 *
 * returns:
 *	UPAP_AUTHNAK: Authentication failed.
 *	UPAP_AUTHACK: Authentication succeeded.
 * In either case, msg points to an appropriate message.
 */
int
check_passwd(unit, auser, userlen, apasswd, passwdlen, msg, msglen)
    int unit;
    char *auser;
    int userlen;
    char *apasswd;
    int passwdlen;
    char **msg;
    int *msglen;
{
    int ret = UPAP_AUTHACK;
    char *filename;
    FILE *f = NULL;
    struct wordlist *addrs = NULL;
    char passwd[256], user[256];
    char secret[MAXWORDLEN];

    /*
     * Make copies of apasswd and auser, then null-terminate them.
     */
    BCOPY(apasswd, passwd, passwdlen);
    passwd[passwdlen] = '\0';
    BCOPY(auser, user, userlen);
    user[userlen] = '\0';

    if (ppp_if[unit]->uselogin)
	{
        if (loginUserVerify (user, passwd) == ERROR)
	    {
	    ret = UPAP_AUTHNAK;
            syslog(LOG_WARNING, "upap login failure for %s", user);
	    }
        }
    else if (pppSecretFind (user, ppp_if[unit]->our_name, secret, &addrs) < 0 ||
        (secret[0] != 0 && strcmp(passwd, secret) != 0 &&
	((pppCryptRtn == NULL) ||
        strcmp((char *) (*pppCryptRtn) (secret, passwd), passwd) != 0)))
        {
        /*
         * Open the file of upap secrets and scan for a suitable secret
         * for authenticating this user.
         */

        if ((filename = ppp_if[unit]->options->pap_file) != NULL)
            f = fopen(filename, "r");

        if (f == NULL) {
	    syslog(LOG_ERR, "Can't open upap password file %s", filename);
	    ret = UPAP_AUTHNAK;
        } else {
	    check_access(f, filename);
            if (scan_authfile(f, user, ppp_if[unit]->our_name, secret,
		&addrs, filename) < 0 || (secret[0] != 0 &&
		strcmp(passwd, secret) != 0 && ((pppCryptRtn == NULL) ||
		strcmp((char *) (*pppCryptRtn) (secret, passwd), passwd) != 0)))
		{
                syslog(LOG_WARNING, "upap authentication failure for %s", user);
	        ret = UPAP_AUTHNAK;
	        }
	    fclose(f);
            }
        }

    if (ret == UPAP_AUTHNAK) {
        *msg = "Login incorrect";
        *msglen = strlen(*msg);
	if (addrs != NULL)
	    free_wordlist(addrs);

    } else {
	*msg = "Login ok";
	*msglen = strlen(*msg);
	if (ppp_if[unit]->addresses != NULL)
	    free_wordlist(ppp_if[unit]->addresses);
	ppp_if[unit]->addresses = addrs;
    }

    return ret;
}


/*
 * upap_login - Check the user name and password against the system
 * password database, and login the user if OK.
 *
 * returns:
 *	UPAP_AUTHNAK: Login failed.
 *	UPAP_AUTHACK: Login succeeded.
 * In either case, msg points to an appropriate message.
 */

#ifdef	notyet
static int
login(user, passwd)
    char *user;
    char *passwd;
{
    struct passwd *pw;
    char *epasswd;
    char *tty;

    if ((pw = getpwnam(user)) == NULL) {
        return (UPAP_AUTHNAK);
    }

    /*
     * XXX If no passwd, let them login without one.
     */

    if (pw->pw_passwd == '\0') {
        return (UPAP_AUTHACK);
    }

    epasswd = crypt(passwd, pw->pw_passwd);
    if (strcmp(epasswd, pw->pw_passwd)) {
        return (UPAP_AUTHNAK);
    }

    syslog(LOG_INFO, "user %s logged in", user);

    /*
     * Write a wtmp entry for this user.
     */
    tty = strrchr(devname, '/');
    if (tty == NULL)
        tty = devname;
    else
        tty++;
    logwtmp(tty, user, "");             /* Add wtmp login entry */
    logged_in = TRUE;

}