www.pudn.com > vxworks_tcpip_code.rar > auth.c
/* 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;
}
/*
* logout - Logout the user.
*/
static void
logout()
{
char *tty;
tty = strrchr(ppp_if[ppp_unit]->devname, '/');
if (tty == NULL)
tty = ppp_if[ppp_unit]->devname;
else
tty++;
ppp_if[ppp_unit]->logged_in = FALSE;
}
#endif /* notyet */
/*
* null_login - Check if a username of "" and a password of "" are
* acceptable, and iff so, set the list of acceptable IP addresses
* and return 1.
*/
static int
null_login(unit)
int unit;
{
char *filename;
FILE *f = NULL;
int i, ret;
struct wordlist *addrs = NULL;
char secret[MAXWORDLEN];
i = pppSecretFind ("", ppp_if[unit]->our_name, secret, &addrs);
ret = i >= 0 && (i & NONWILD_CLIENT) != 0 && secret[0] == 0;
if (!ret)
{
/*
* Open the file of upap secrets and scan for a suitable secret.
* We don't accept a wildcard client.
*/
if ((filename = ppp_if[unit]->options->pap_file) != NULL)
f = fopen(filename, "r");
if (f == NULL)
return 0;
check_access(f, filename);
i = scan_authfile(f, "", ppp_if[unit]->our_name, secret, &addrs,
filename);
ret = i >= 0 && (i & NONWILD_CLIENT) != 0 && secret[0] == 0;
fclose(f);
}
if (ret) {
if (ppp_if[unit]->addresses != NULL)
free_wordlist(ppp_if[unit]->addresses);
ppp_if[unit]->addresses = addrs;
}
return ret;
}
/*
* get_upap_passwd - get a password for authenticating ourselves with
* our peer using PAP. Returns 1 on success, 0 if no suitable password
* could be found.
*/
static int
get_upap_passwd()
{
char *filename;
FILE *f = NULL;
char secret[MAXWORDLEN];
if (pppSecretFind (ppp_if[ppp_unit]->user, ppp_if[ppp_unit]->remote_name,
secret, NULL) < 0)
{
if ((filename = ppp_if[ppp_unit]->options->pap_file) != NULL)
f = fopen(filename, "r");
if (f == NULL)
return 0;
check_access(f, filename);
if (scan_authfile(f, ppp_if[ppp_unit]->user,
ppp_if[ppp_unit]->remote_name, secret, NULL, filename) < 0)
{
fclose(f);
return 0;
}
fclose(f);
}
strncpy(ppp_if[ppp_unit]->passwd, secret, MAXSECRETLEN);
ppp_if[ppp_unit]->passwd[MAXSECRETLEN-1] = 0;
return 1;
}
/*
* have_upap_secret - check whether we have a PAP file with any
* secrets that we could possibly use for authenticating the peer.
*/
static int
have_upap_secret()
{
FILE *f = NULL;
int ret;
char *filename;
if (ppp_if[ppp_unit]->uselogin)
return 1;
if (pppSecretFind (NULL, ppp_if[ppp_unit]->our_name, NULL, NULL) < 0)
{
if ((filename = ppp_if[ppp_unit]->options->pap_file) != NULL)
f = fopen(filename, "r");
if (f == NULL)
return 0;
ret = scan_authfile(f, NULL, ppp_if[ppp_unit]->our_name, NULL, NULL,
filename);
fclose(f);
if (ret < 0)
return 0;
}
return 1;
}
/*
* have_chap_secret - check whether we have a CHAP file with a
* secret that we could possibly use for authenticating `client'
* on `server'. Either can be the null string, meaning we don't
* know the identity yet.
*/
static int
have_chap_secret(client, server)
char *client;
char *server;
{
FILE *f = NULL;
int ret;
char *filename;
if (client[0] == 0)
client = NULL;
else if (server[0] == 0)
server = NULL;
if (pppSecretFind (client, server, NULL, NULL) < 0)
{
if ((filename = ppp_if[ppp_unit]->options->chap_file) != NULL)
f = fopen(filename, "r");
if (f == NULL)
return 0;
ret = scan_authfile(f, client, server, NULL, NULL, filename);
fclose(f);
if (ret < 0)
return 0;
}
return 1;
}
/*
* get_secret - open the CHAP secret file and return the secret
* for authenticating the given client on the given server.
* (We could be either client or server).
*/
int
get_secret(unit, client, server, secret, secret_len, save_addrs)
int unit;
char *client;
char *server;
char *secret;
int *secret_len;
int save_addrs;
{
FILE *f = NULL;
int ret, len;
char *filename;
struct wordlist *addrs = NULL;
char secbuf[MAXWORDLEN];
secbuf[0] = 0;
if (pppSecretFind (client, server, secbuf, &addrs) < 0)
{
if ((filename = ppp_if[unit]->options->chap_file) != NULL)
f = fopen(filename, "r");
if (f == NULL) {
syslog(LOG_ERR, "Can't open chap secret file %s", filename);
return 0;
}
check_access(f, filename);
ret = scan_authfile(f, client, server, secbuf, &addrs, filename);
fclose(f);
if (ret < 0)
return 0;
}
if (save_addrs) {
if (ppp_if[unit]->addresses != NULL)
free_wordlist(ppp_if[unit]->addresses);
ppp_if[unit]->addresses = addrs;
}
len = strlen(secbuf);
if (len > MAXSECRETLEN) {
syslog(LOG_ERR, "Secret for %s on %s is too long", client, server);
len = MAXSECRETLEN;
}
BCOPY(secbuf, secret, len);
*secret_len = len;
return 1;
}
/*
* auth_ip_addr - check whether the peer is authorized to use
* a given IP address. Returns 1 if authorized, 0 otherwise.
*/
int
auth_ip_addr(unit, addr)
int unit;
u_long addr;
{
u_long a;
struct wordlist *addrs;
/* don't allow loopback or multicast address */
if (bad_ip_adrs(addr))
return 0;
if ((addrs = ppp_if[unit]->addresses) == NULL)
return 1; /* no restriction */
for (; addrs != NULL; addrs = addrs->next) {
/* "-" means no addresses authorized */
if (strcmp(addrs->word, "-") == 0)
break;
if ((a = inet_addr(addrs->word)) == -1) {
if ((a = hostGetByName (addrs->word)) == NULL) {
syslog(LOG_WARNING, "unknown host %s in auth. address list",
addrs->word);
continue;
}
}
if (addr == a)
return 1;
}
return 0; /* not in list => can't have it */
}
/*
* bad_ip_adrs - return 1 if the IP address is one we don't want
* to use, such as an address in the loopback net or a multicast address.
* addr is in network byte order.
*/
int
bad_ip_adrs(addr)
u_long addr;
{
addr = ntohl(addr);
#if CPU==SIMSPARCSOLARIS
return IN_MULTICAST(addr) || IN_BADCLASS(addr);
#else
return (addr >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET
|| IN_MULTICAST(addr) || IN_BADCLASS(addr);
#endif
}
/*
* check_access - complain if a secret file has too-liberal permissions.
*/
void
check_access(f, fileName)
FILE *f;
char *fileName;
{
struct stat sbuf;
if (fstat(fileno(f), &sbuf) < 0) {
syslog(LOG_WARNING, "cannot stat secret file %s: %m", fileName);
} else if ((sbuf.st_mode & (S_IRWXG | S_IRWXO)) != 0) {
syslog(LOG_WARNING, "Warning - secret file %s has world and/or group access", fileName);
}
}
/*
* scan_authfile - Scan an authorization file for a secret suitable
* for authenticating `client' on `server'. The return value is -1
* if no secret is found, otherwise >= 0. The return value has
* NONWILD_CLIENT set if the secret didn't have "*" for the client, and
* NONWILD_SERVER set if the secret didn't have "*" for the server.
* Any following words on the line (i.e. address authorization
* info) are placed in a wordlist and returned in *addrs.
*/
static int
scan_authfile(f, client, server, secret, addrs, fileName)
FILE *f;
char *client;
char *server;
char *secret;
struct wordlist **addrs;
char *fileName;
{
int newline, xxx;
int got_flag, best_flag;
FILE *sf;
struct wordlist *ap, *addr_list, *addr_last;
char word[MAXWORDLEN];
char atfile[MAXWORDLEN];
if (addrs != NULL)
*addrs = NULL;
addr_list = NULL;
if (!getword(f, word, &newline, fileName))
return -1; /* file is empty??? */
newline = 1;
best_flag = -1;
for (;;) {
/*
* Skip until we find a word at the start of a line.
*/
while (!newline && getword(f, word, &newline, fileName))
;
if (!newline)
break; /* got to end of file */
/*
* Got a client - check if it's a match or a wildcard.
*/
got_flag = 0;
if (client != NULL && client[0] && strcmp(word, client) != 0 &&
!ISWILD(word)) {
newline = 0;
continue;
}
if (!ISWILD(word))
got_flag = NONWILD_CLIENT;
/*
* Now get a server and check if it matches.
*/
if (!getword(f, word, &newline, fileName))
break;
if (newline)
continue;
if (server != NULL && server[0] && strcmp(word, server) != 0 &&
!ISWILD(word))
continue;
if (!ISWILD(word))
got_flag |= NONWILD_SERVER;
/*
* Got some sort of a match - see if it's better than what
* we have already.
*/
if (got_flag <= best_flag)
continue;
/*
* Get the secret.
*/
if (!getword(f, word, &newline, fileName))
break;
if (newline)
continue;
/*
* Special syntax: @filename means read secret from file.
*/
if (word[0] == '@') {
strcpy(atfile, word+1);
if ((sf = fopen(atfile, "r")) == NULL) {
syslog(LOG_WARNING, "can't open indirect secret file %s",
atfile);
continue;
}
check_access(sf, atfile);
if (!getword(sf, word, &xxx, atfile)) {
syslog(LOG_WARNING, "no secret in indirect secret file %s",
atfile);
fclose(sf);
continue;
}
fclose(sf);
}
if (secret != NULL)
strcpy(secret, word);
best_flag = got_flag;
/*
* Now read address authorization info and make a wordlist.
*/
if (addr_list)
free_wordlist(addr_list);
addr_list = addr_last = NULL;
for (;;) {
if (!getword(f, word, &newline, fileName) || newline)
break;
ap = (struct wordlist *) malloc(sizeof(struct wordlist)
+ strlen(word));
if (ap == NULL)
novm("authorized addresses");
ap->next = NULL;
strcpy(ap->word, word);
if (addr_list == NULL)
addr_list = ap;
else
addr_last->next = ap;
addr_last = ap;
}
if (!newline)
break;
}
if (addrs != NULL)
*addrs = addr_list;
else if (addr_list != NULL)
free_wordlist(addr_list);
return best_flag;
}
/*
* free_wordlist - release memory allocated for a wordlist.
*/
static void
free_wordlist(wp)
struct wordlist *wp;
{
struct wordlist *next;
while (wp != NULL) {
next = wp->next;
free(wp);
wp = next;
}
}