X-Git-Url: http://git.ozlabs.org/?p=ppp.git;a=blobdiff_plain;f=pppd%2Fauth.c;h=1cbc14973acad1d0ef4a54ad7843f3275a78f924;hp=cdeb2b6b7874daa292c32b23082f89c4134eae93;hb=6041de91d21e0c9fe92bcec7b8a9231ed98145c3;hpb=0b63a24d54ba4708c88e31bdd74b0145956c1478 diff --git a/pppd/auth.c b/pppd/auth.c index cdeb2b6..1cbc149 100644 --- a/pppd/auth.c +++ b/pppd/auth.c @@ -33,36 +33,39 @@ */ #ifndef lint -static char rcsid[] = "$Id: auth.c,v 1.1 1993/11/11 03:54:25 paulus Exp $"; +static char rcsid[] = "$Id: auth.c,v 1.20 1995/12/18 03:43:04 paulus Exp $"; #endif #include #include +#include #include #include #include #include #include +#include #include #include #include -#include "ppp.h" +#ifdef HAS_SHADOW +#include +#include +#ifndef PW_PPP +#define PW_PPP PW_LOGIN +#endif +#endif + #include "pppd.h" #include "fsm.h" #include "lcp.h" #include "upap.h" -#include "chap.h" -#include "ipcp.h" #include "pathnames.h" -#ifdef sparc +#if defined(sun) && defined(sparc) #include -#ifndef __GNUC__ -/* why alloca.h doesn't define what alloca() returns is a mystery */ -char *alloca __ARGS((int)); -#endif /*__GNUC__*/ #endif /*sparc*/ /* Used for storing a sequence of words. Usually malloced. */ @@ -80,20 +83,10 @@ struct wordlist { #define FALSE 0 #define TRUE 1 -extern char user[]; -extern char passwd[]; -extern char devname[]; -extern char our_name[]; -extern char remote_name[]; -extern char hostname[]; -extern int uselogin; -extern int usehostname; -extern int auth_required; - /* Records which authentication operations haven't completed yet. */ -static int auth_pending[NPPP]; +static int auth_pending[NUM_PPP]; static int logged_in; -static struct wordlist *addresses[NPPP]; +static struct wordlist *addresses[NUM_PPP]; /* Bits in auth_pending[] */ #define UPAP_WITHPEER 1 @@ -101,19 +94,20 @@ static struct wordlist *addresses[NPPP]; #define CHAP_WITHPEER 4 #define CHAP_PEER 8 -/* Prototypes */ -void check_access __ARGS((FILE *, char *)); +/* Prototypes for procedures local to this file. */ -static int login __ARGS((char *, char *, char **, int *)); -static void logout __ARGS((void)); -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 *, +static void network_phase __P((int)); +static int login __P((char *, char *, char **, int *)); +static void logout __P((void)); +static int null_login __P((int)); +static int get_upap_passwd __P((void)); +static int have_upap_secret __P((void)); +static int have_chap_secret __P((char *, char *)); +static int scan_authfile __P((FILE *, char *, char *, char *, struct wordlist **, char *)); -static void free_wordlist __ARGS((struct wordlist *)); +static void free_wordlist __P((struct wordlist *)); -extern char *crypt __ARGS((char *, char *)); +extern char *crypt __P((char *, char *)); /* * An Open on LCP has requested a change from Dead to Establish phase. @@ -133,13 +127,31 @@ void link_terminated(unit) int unit; { + if (phase == PHASE_DEAD) + return; if (logged_in) logout(); - if (lcp_wantoptions[unit].restart) { - lcp_lowerdown(unit); - lcp_lowerup(unit); - } else - EXIT(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; +{ + int i; + struct protent *protp; + + for (i = 0; (protp = protocols[i]) != NULL; ++i) { + if (protp->protocol != PPP_LCP && protp->lowerdown != NULL) + (*protp->lowerdown)(unit); + if (protp->protocol < 0xC000 && protp->close != NULL) + (*protp->close)(unit); + } + phase = PHASE_TERMINATE; } /* @@ -154,17 +166,31 @@ link_established(unit) lcp_options *wo = &lcp_wantoptions[unit]; lcp_options *go = &lcp_gotoptions[unit]; lcp_options *ho = &lcp_hisoptions[unit]; + int i; + struct protent *protp; + + /* + * Tell higher-level protocols that LCP is up. + */ + for (i = 0; (protp = protocols[i]) != NULL; ++i) + if (protp->protocol != PPP_LCP && protp->lowerup != NULL) + (*protp->lowerup)(unit); if (auth_required && !(go->neg_chap || go->neg_upap)) { /* - * We wanted the peer to authenticate himself, and he refused: - * tell him to go away. + * 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. */ - syslog(LOG_WARNING, "peer refused to authenticate"); - lcp_close(unit); - return; + if (!wo->neg_upap || !null_login(unit)) { + syslog(LOG_WARNING, "peer refused to authenticate"); + lcp_close(unit, "peer refused to authenticate"); + phase = PHASE_TERMINATE; + return; + } } + phase = PHASE_AUTHENTICATE; auth = 0; if (go->neg_chap) { ChapAuthPeer(unit, our_name, go->chap_mdtype); @@ -183,7 +209,23 @@ link_established(unit) auth_pending[unit] = auth; if (!auth) - ipcp_open(unit); + network_phase(unit); +} + +/* + * Proceed to the network phase. + */ +static void +network_phase(unit) + int unit; +{ + int i; + struct protent *protp; + + phase = PHASE_NETWORK; + for (i = 0; (protp = protocols[i]) != NULL; ++i) + if (protp->protocol < 0xC000 && protp->open != NULL) + (*protp->open)(unit); } /* @@ -196,7 +238,8 @@ auth_peer_fail(unit, protocol) /* * Authentication failure: take the link down */ - lcp_close(unit); + lcp_close(unit, "Authentication failed"); + phase = PHASE_TERMINATE; } /* @@ -209,10 +252,10 @@ auth_peer_success(unit, protocol) int bit; switch (protocol) { - case CHAP: + case PPP_CHAP: bit = CHAP_PEER; break; - case UPAP: + case PPP_PAP: bit = UPAP_PEER; break; default: @@ -226,7 +269,7 @@ auth_peer_success(unit, protocol) * proceed to the network phase. */ if ((auth_pending[unit] &= ~bit) == 0) - ipcp_open(unit); + network_phase(unit); } /* @@ -253,15 +296,16 @@ auth_withpeer_success(unit, protocol) int bit; switch (protocol) { - case CHAP: + case PPP_CHAP: bit = CHAP_WITHPEER; break; - case UPAP: + case PPP_PAP: bit = UPAP_WITHPEER; break; default: syslog(LOG_WARNING, "auth_peer_success: unknown protocol %x", protocol); + bit = 0; } /* @@ -269,7 +313,7 @@ auth_withpeer_success(unit, protocol) * proceed to the network phase. */ if ((auth_pending[unit] &= ~bit) == 0) - ipcp_open(unit); + network_phase(unit); } @@ -362,16 +406,16 @@ check_passwd(unit, auser, userlen, apasswd, passwdlen, msg, msglen) f = fopen(filename, "r"); if (f == NULL) { if (!uselogin) { - syslog(LOG_ERR, "Can't open upap password file %s: %m", filename); + syslog(LOG_ERR, "Can't open PAP password file %s: %m", filename); ret = UPAP_AUTHNAK; } } else { check_access(f, filename); if (scan_authfile(f, user, our_name, secret, &addrs, filename) < 0 - || (secret[0] != 0 && strcmp(passwd, secret) != 0 + || (secret[0] != 0 && (cryptpap || strcmp(passwd, secret) != 0) && strcmp(crypt(passwd, secret), secret) != 0)) { - syslog(LOG_WARNING, "upap authentication failure for %s", user); + syslog(LOG_WARNING, "PAP authentication failure for %s", user); ret = UPAP_AUTHNAK; } fclose(f); @@ -380,7 +424,7 @@ check_passwd(unit, auser, userlen, apasswd, passwdlen, msg, msglen) if (uselogin && ret == UPAP_AUTHACK) { ret = login(user, passwd, msg, msglen); if (ret == UPAP_AUTHNAK) { - syslog(LOG_WARNING, "upap login failure for %s", user); + syslog(LOG_WARNING, "PAP login failure for %s", user); } } @@ -394,7 +438,7 @@ check_passwd(unit, auser, userlen, apasswd, passwdlen, msg, msglen) */ if (attempts++ >= 10) { syslog(LOG_WARNING, "%d LOGIN FAILURES ON %s, %s", - attempts, devname, user); + attempts, devnam, user); quit(); } if (attempts > 3) @@ -435,10 +479,23 @@ login(user, passwd, msg, msglen) char *epasswd; char *tty; +#ifdef HAS_SHADOW + struct spwd *spwd; + struct spwd *getspnam(); +#endif + if ((pw = getpwnam(user)) == NULL) { return (UPAP_AUTHNAK); } +#ifdef HAS_SHADOW + if ((spwd = getspnam(user)) == NULL) { + pw->pw_passwd = ""; + } else { + pw->pw_passwd = spwd->sp_pwdp; + } +#endif + /* * XXX If no passwd, let them login without one. */ @@ -446,21 +503,27 @@ login(user, passwd, msg, msglen) return (UPAP_AUTHACK); } +#ifdef HAS_SHADOW + if ((pw->pw_passwd && pw->pw_passwd[0] == '@' + && pw_auth (pw->pw_passwd+1, pw->pw_name, PW_PPP, NULL)) + || !valid (passwd, pw)) { + return (UPAP_AUTHNAK); + } +#else epasswd = crypt(passwd, pw->pw_passwd); if (strcmp(epasswd, pw->pw_passwd)) { return (UPAP_AUTHNAK); } +#endif 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++; + tty = devnam; + if (strncmp(tty, "/dev/", 5) == 0) + tty += 5; logwtmp(tty, user, ""); /* Add wtmp login entry */ logged_in = TRUE; @@ -475,16 +538,54 @@ logout() { char *tty; - tty = strrchr(devname, '/'); - if (tty == NULL) - tty = devname; - else - tty++; + tty = devnam; + if (strncmp(tty, "/dev/", 5) == 0) + tty += 5; logwtmp(tty, "", ""); /* Wipe out wtmp logout entry */ logged_in = FALSE; } +/* + * 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; + int i, ret; + struct wordlist *addrs; + char secret[MAXWORDLEN]; + + /* + * Open the file of upap secrets and scan for a suitable secret. + * We don't accept a wildcard client. + */ + filename = _PATH_UPAPFILE; + addrs = NULL; + f = fopen(filename, "r"); + if (f == NULL) + return 0; + check_access(f, filename); + + i = scan_authfile(f, "", our_name, secret, &addrs, filename); + ret = i >= 0 && (i & NONWILD_CLIENT) != 0 && secret[0] == 0; + + if (ret) { + if (addresses[unit] != NULL) + free_wordlist(addresses[unit]); + addresses[unit] = addrs; + } + + fclose(f); + 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 @@ -543,7 +644,7 @@ have_upap_secret() * on `server'. Either can be the null string, meaning we don't * know the identity yet. */ -int +static int have_chap_secret(client, server) char *client; char *server; @@ -583,6 +684,7 @@ get_secret(unit, client, server, secret, secret_len, save_addrs) char *server; char *secret; int *secret_len; + int save_addrs; { FILE *f; int ret, len; @@ -630,33 +732,90 @@ get_secret(unit, client, server, secret, secret_len, save_addrs) int auth_ip_addr(unit, addr) int unit; - u_long addr; + u_int32_t addr; { - u_long a; + u_int32_t a, mask; + int accept; + char *ptr_word, *ptr_mask; struct hostent *hp; + struct netent *np; struct wordlist *addrs; + /* don't allow loopback or multicast address */ + if (bad_ip_adrs(addr)) + return 0; + if ((addrs = addresses[unit]) == NULL) return 1; /* no restriction */ for (; addrs != NULL; addrs = addrs->next) { /* "-" means no addresses authorized */ - if (strcmp(addrs->word, "-") == 0) + ptr_word = addrs->word; + if (strcmp(ptr_word, "-") == 0) break; - if ((a = inet_addr(addrs->word)) == -1) { - if ((hp = gethostbyname(addrs->word)) == NULL) { - syslog(LOG_WARNING, "unknown host %s in auth. address list", - addrs->word); + + accept = 1; + if (*ptr_word == '!') { + accept = 0; + ++ptr_word; + } + + mask = ~ (u_int32_t) 0; + ptr_mask = strchr (ptr_word, '/'); + if (ptr_mask != NULL) { + int bit_count; + + bit_count = (int) strtol (ptr_mask+1, (char **) 0, 10); + if (bit_count <= 0 || bit_count > 32) { + syslog (LOG_WARNING, + "invalid address length %s in auth. address list", + ptr_mask); continue; - } else - a = *(u_long *)hp->h_addr; + } + *ptr_mask = '\0'; + mask <<= 32 - bit_count; } - if (addr == a) - return 1; + + hp = gethostbyname(ptr_word); + if (hp != NULL && hp->h_addrtype == AF_INET) { + a = *(u_int32_t *)hp->h_addr; + mask = ~ (u_int32_t) 0; /* are we sure we want this? */ + } else { + np = getnetbyname (ptr_word); + if (np != NULL && np->n_addrtype == AF_INET) + a = htonl (*(u_int32_t *)np->n_net); + else + a = inet_addr (ptr_word); + } + + if (ptr_mask != NULL) + *ptr_mask = '/'; + + if (a == -1L) + syslog (LOG_WARNING, + "unknown host %s in auth. address list", + addrs->word); + else + if (((addr ^ a) & mask) == 0) + return accept; } 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_int32_t addr; +{ + addr = ntohl(addr); + return (addr >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET + || IN_MULTICAST(addr) || IN_BADCLASS(addr); +} + /* * check_access - complain if a secret file has too-liberal permissions. */ @@ -783,7 +942,7 @@ scan_authfile(f, client, server, secret, addrs, filename) */ if (addr_list) free_wordlist(addr_list); - addr_list = NULL; + addr_list = addr_last = NULL; for (;;) { if (!getword(f, word, &newline, filename) || newline) break;