X-Git-Url: http://git.ozlabs.org/?p=ppp.git;a=blobdiff_plain;f=pppd%2Fauth.c;h=bff01a7b432d54d1b6550b806eb6675a7a104b22;hp=7a77a83381c82b926a52e7b1dae4acf2c731b3cd;hb=706493747ac6e7d99171a06de391c4a93f3df094;hpb=75951d7bb62003e37dd390e773df19f16250d27d diff --git a/pppd/auth.c b/pppd/auth.c index 7a77a83..bff01a7 100644 --- a/pppd/auth.c +++ b/pppd/auth.c @@ -32,9 +32,7 @@ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. */ -#ifndef lint -static char rcsid[] = "$Id: auth.c,v 1.47 1999/03/19 01:17:51 paulus Exp $"; -#endif +#define RCSID "$Id: auth.c,v 1.71 2001/11/09 10:33:42 paulus Exp $" #include #include @@ -78,11 +76,7 @@ static char rcsid[] = "$Id: auth.c,v 1.47 1999/03/19 01:17:51 paulus Exp $"; #endif #include "pathnames.h" -/* Used for storing a sequence of words. Usually malloced. */ -struct wordlist { - struct wordlist *next; - char *word; -}; +static const char rcsid[] = RCSID; /* Bits in scan_authfile return value */ #define NONWILD_SERVER 1 @@ -102,6 +96,13 @@ static int logged_in; /* List of addresses which the peer may use. */ static struct permitted_ip *addresses[NUM_PPP]; +/* Wordlist giving addresses which the peer may use + without authenticating itself. */ +static struct wordlist *noauth_addrs; + +/* Extra options to apply, from the secrets file entry for the peer. */ +static struct wordlist *extra_options; + /* Number of network protocols which we have opened. */ static int num_np_open; @@ -111,6 +112,38 @@ static int num_np_up; /* Set if we got the contents of passwd[] from the pap-secrets file. */ static int passwd_from_file; +/* Set if we require authentication only because we have a default route. */ +static bool default_auth; + +/* Hook to enable a plugin to control the idle time limit */ +int (*idle_time_hook) __P((struct ppp_idle *)) = NULL; + +/* Hook for a plugin to say whether we can possibly authenticate any peer */ +int (*pap_check_hook) __P((void)) = NULL; + +/* Hook for a plugin to check the PAP user and password */ +int (*pap_auth_hook) __P((char *user, char *passwd, char **msgp, + struct wordlist **paddrs, + struct wordlist **popts)) = NULL; + +/* Hook for a plugin to know about the PAP user logout */ +void (*pap_logout_hook) __P((void)) = NULL; + +/* Hook for a plugin to get the PAP password for authenticating us */ +int (*pap_passwd_hook) __P((char *user, char *passwd)) = NULL; + +/* Hook for a plugin to say whether it is OK if the peer + refuses to authenticate. */ +int (*null_auth_hook) __P((struct wordlist **paddrs, + struct wordlist **popts)) = NULL; + +/* A notifier for when the peer has authenticated itself, + and we are proceeding to the network phase. */ +struct notifier *auth_up_notifier = NULL; + +/* A notifier for when the link goes down. */ +struct notifier *link_down_notifier = NULL; + /* * This is used to ensure that we don't start an auth-up/down * script while one is already running. @@ -124,6 +157,8 @@ static enum script_state auth_state = s_down; static enum script_state auth_script_state = s_down; static pid_t auth_script_pid = 0; +static int used_login; /* peer authenticated against login database */ + /* * Option variables. */ @@ -137,6 +172,8 @@ bool allow_any_ip = 0; /* Allow peer to use any IP address */ bool explicit_remote = 0; /* User specified explicit remote name */ char remote_name[MAXNAMELEN]; /* Peer's name for authentication */ +static char *uafname; /* name of most recent +ua file */ + /* Bits in auth_pending[] */ #define PAP_WITHPEER 1 #define PAP_PEER 2 @@ -150,7 +187,7 @@ extern char *crypt __P((const char *, const char *)); static void network_phase __P((int)); static void check_idle __P((void *)); static void connect_time_expired __P((void *)); -static int plogin __P((char *, char *, char **, int *)); +static int plogin __P((char *, char *, char **)); static void plogout __P((void)); static int null_login __P((int)); static int get_pap_passwd __P((char *)); @@ -158,58 +195,86 @@ static int have_pap_secret __P((int *)); static int have_chap_secret __P((char *, char *, int, int *)); static int ip_addr_check __P((u_int32_t, struct permitted_ip *)); static int scan_authfile __P((FILE *, char *, char *, char *, - struct wordlist **, char *)); + struct wordlist **, struct wordlist **, + char *)); static void free_wordlist __P((struct wordlist *)); static void auth_script __P((char *)); static void auth_script_done __P((void *)); -static void set_allowed_addrs __P((int, struct wordlist *)); +static void set_allowed_addrs __P((int, struct wordlist *, struct wordlist *)); static int some_ip_ok __P((struct wordlist *)); static int setupapfile __P((char **)); static int privgroup __P((char **)); +static int set_noauth_addr __P((char **)); static void check_access __P((FILE *, char *)); +static int wordlist_count __P((struct wordlist *)); /* * Authentication-related options. */ option_t auth_options[] = { + { "auth", o_bool, &auth_required, + "Require authentication from peer", OPT_PRIO | 1 }, + { "noauth", o_bool, &auth_required, + "Don't require peer to authenticate", OPT_PRIOSUB | OPT_PRIV, + &allow_any_ip }, { "require-pap", o_bool, &lcp_wantoptions[0].neg_upap, - "Require PAP authentication from peer", 1, &auth_required }, + "Require PAP authentication from peer", + OPT_PRIOSUB | 1, &auth_required }, { "+pap", o_bool, &lcp_wantoptions[0].neg_upap, - "Require PAP authentication from peer", 1, &auth_required }, + "Require PAP authentication from peer", + OPT_ALIAS | OPT_PRIOSUB | 1, &auth_required }, + { "require-chap", o_bool, &lcp_wantoptions[0].neg_chap, + "Require CHAP authentication from peer", + OPT_PRIOSUB | 1, &auth_required }, + { "+chap", o_bool, &lcp_wantoptions[0].neg_chap, + "Require CHAP authentication from peer", + OPT_ALIAS | OPT_PRIOSUB | 1, &auth_required }, + { "refuse-pap", o_bool, &refuse_pap, "Don't agree to auth to peer with PAP", 1 }, { "-pap", o_bool, &refuse_pap, - "Don't allow PAP authentication with peer", 1 }, - { "require-chap", o_bool, &lcp_wantoptions[0].neg_chap, - "Require CHAP authentication from peer", 1, &auth_required }, - { "+chap", o_bool, &lcp_wantoptions[0].neg_chap, - "Require CHAP authentication from peer", 1, &auth_required }, + "Don't allow PAP authentication with peer", OPT_ALIAS | 1 }, + { "refuse-chap", o_bool, &refuse_chap, "Don't agree to auth to peer with CHAP", 1 }, { "-chap", o_bool, &refuse_chap, - "Don't allow CHAP authentication with peer", 1 }, + "Don't allow CHAP authentication with peer", OPT_ALIAS | 1 }, + { "name", o_string, our_name, "Set local name for authentication", - OPT_PRIV|OPT_STATIC, NULL, MAXNAMELEN }, + OPT_PRIO | OPT_PRIV | OPT_STATIC, NULL, MAXNAMELEN }, + + { "+ua", o_special, (void *)setupapfile, + "Get PAP user and password from file", + OPT_PRIO | OPT_A2STRVAL, &uafname }, + { "user", o_string, user, - "Set name for auth with peer", OPT_STATIC, NULL, MAXNAMELEN }, + "Set name for auth with peer", OPT_PRIO | OPT_STATIC, NULL, MAXNAMELEN }, + + { "password", o_string, passwd, + "Password for authenticating us to the peer", + OPT_PRIO | OPT_STATIC | OPT_HIDE, NULL, MAXSECRETLEN }, + { "usehostname", o_bool, &usehostname, "Must use hostname for authentication", 1 }, + { "remotename", o_string, remote_name, - "Set remote name for authentication", OPT_STATIC, + "Set remote name for authentication", OPT_PRIO | OPT_STATIC, &explicit_remote, MAXNAMELEN }, - { "auth", o_bool, &auth_required, - "Require authentication from peer", 1 }, - { "noauth", o_bool, &auth_required, - "Don't require peer to authenticate", OPT_PRIV, &allow_any_ip }, - { "login", o_bool, &uselogin, + + { "login", o_bool, &uselogin, "Use system password database for PAP", 1 }, + { "papcrypt", o_bool, &cryptpap, "PAP passwords are encrypted", 1 }, - { "+ua", o_special, setupapfile, - "Get PAP user and password from file" }, - { "privgroup", o_special, privgroup, - "Allow group members to use privileged options", OPT_PRIV }, + + { "privgroup", o_special, (void *)privgroup, + "Allow group members to use privileged options", OPT_PRIV | OPT_A2LIST }, + + { "allow-ip", o_special, (void *)set_noauth_addr, + "Set IP address(es) which can be used without authentication", + OPT_PRIV | OPT_A2LIST }, + { NULL } }; @@ -220,36 +285,47 @@ static int setupapfile(argv) char **argv; { - FILE * ufile; + FILE *ufile; int l; + char u[MAXNAMELEN], p[MAXSECRETLEN]; + char *fname; lcp_allowoptions[0].neg_upap = 1; /* open user info file */ + fname = strdup(*argv); + if (fname == NULL) + novm("+ua file name"); seteuid(getuid()); - ufile = fopen(*argv, "r"); + ufile = fopen(fname, "r"); seteuid(0); if (ufile == NULL) { - option_error("unable to open user login data file %s", *argv); + option_error("unable to open user login data file %s", fname); return 0; } - check_access(ufile, *argv); + check_access(ufile, fname); + uafname = fname; /* get username */ - if (fgets(user, MAXNAMELEN - 1, ufile) == NULL - || fgets(passwd, MAXSECRETLEN - 1, ufile) == NULL){ - option_error("unable to read user login data file %s", *argv); + if (fgets(u, MAXNAMELEN - 1, ufile) == NULL + || fgets(p, MAXSECRETLEN - 1, ufile) == NULL){ + option_error("unable to read user login data file %s", fname); return 0; } fclose(ufile); /* get rid of newlines */ - l = strlen(user); - if (l > 0 && user[l-1] == '\n') - user[l-1] = 0; - l = strlen(passwd); - if (l > 0 && passwd[l-1] == '\n') - passwd[l-1] = 0; + l = strlen(u); + if (l > 0 && u[l-1] == '\n') + u[l-1] = 0; + l = strlen(p); + if (l > 0 && p[l-1] == '\n') + p[l-1] = 0; + + if (override_value("user", option_priority, fname)) + strlcpy(user, u, sizeof(user)); + if (override_value("passwd", option_priority, fname)) + strlcpy(passwd, p, sizeof(passwd)); return (1); } @@ -280,6 +356,29 @@ privgroup(argv) } +/* + * set_noauth_addr - set address(es) that can be used without authentication. + * Equivalent to specifying an entry like `"" * "" addr' in pap-secrets. + */ +static int +set_noauth_addr(argv) + char **argv; +{ + char *addr = *argv; + int l = strlen(addr) + 1; + struct wordlist *wp; + + wp = (struct wordlist *) malloc(sizeof(struct wordlist) + l); + if (wp == NULL) + novm("allow-ip argument"); + wp->word = (char *) (wp + 1); + wp->next = noauth_addrs; + BCOPY(addr, wp->word, l); + noauth_addrs = wp; + return 1; +} + + /* * An Open on LCP has requested a change from Dead to Establish phase. * Do what's necessary to bring the physical layer up. @@ -300,9 +399,13 @@ link_terminated(unit) { if (phase == PHASE_DEAD) return; - if (logged_in) - plogout(); - phase = PHASE_DEAD; + if (pap_logout_hook) { + pap_logout_hook(); + } else { + if (logged_in) + plogout(); + } + new_phase(PHASE_DEAD); notice("Connection terminated."); } @@ -316,8 +419,10 @@ link_down(unit) int i; struct protent *protp; + notify(link_down_notifier, 0); auth_state = s_down; if (auth_script_state == s_up && auth_script_pid == 0) { + update_link_stats(unit); auth_script_state = s_down; auth_script(_PATH_AUTHDOWN); } @@ -332,7 +437,7 @@ link_down(unit) num_np_open = 0; num_np_up = 0; if (phase != PHASE_DEAD) - phase = PHASE_TERMINATE; + new_phase(PHASE_ESTABLISH); } /* @@ -361,17 +466,23 @@ link_established(unit) if (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. + * if we have some address(es) it can use without auth, fine, + * otherwise treat it as though it authenticated with PAP using + * a username * of "" and a password of "". If that's not OK, + * boot it out. */ - if (!wo->neg_upap || !null_login(unit)) { + if (noauth_addrs != NULL) { + set_allowed_addrs(unit, NULL, NULL); + } else if (!wo->neg_upap || uselogin || !null_login(unit)) { warn("peer refused to authenticate: terminating link"); lcp_close(unit, "peer refused to authenticate"); + status = EXIT_PEER_AUTH_FAILED; return; } } - phase = PHASE_AUTHENTICATE; + new_phase(PHASE_AUTHENTICATE); + used_login = 0; auth = 0; if (go->neg_chap) { ChapAuthPeer(unit, our_name, go->chap_mdtype); @@ -405,14 +516,13 @@ static void network_phase(unit) int unit; { - int i; - struct protent *protp; lcp_options *go = &lcp_gotoptions[unit]; /* * If the peer had to authenticate, run the auth-up script now. */ if (go->neg_chap || go->neg_upap) { + notify(auth_up_notifier, 0); auth_state = s_up; if (auth_script_state == s_down && auth_script_pid == 0) { auth_script_state = s_up; @@ -425,21 +535,49 @@ network_phase(unit) * If we negotiated callback, do it now. */ if (go->neg_cbcp) { - phase = PHASE_CALLBACK; + new_phase(PHASE_CALLBACK); (*cbcp_protent.open)(unit); return; } #endif - phase = PHASE_NETWORK; -#if 0 + /* + * Process extra options from the secrets file + */ + if (extra_options) { + options_from_list(extra_options, 1); + free_wordlist(extra_options); + extra_options = 0; + } + start_networks(); +} + +void +start_networks() +{ + int i; + struct protent *protp; + + new_phase(PHASE_NETWORK); + +#ifdef HAVE_MULTILINK + if (multilink) { + if (mp_join_bundle()) { + if (updetach && !nodetach) + detach(); + return; + } + } +#endif /* HAVE_MULTILINK */ + +#ifdef PPP_FILTER if (!demand) set_filters(&pass_filter, &active_filter); #endif for (i = 0; (protp = protocols[i]) != NULL; ++i) if (protp->protocol < 0xC000 && protp->enabled_flag && protp->open != NULL) { - (*protp->open)(unit); + (*protp->open)(0); if (protp->protocol != PPP_CCP) ++num_np_open; } @@ -460,6 +598,7 @@ auth_peer_fail(unit, protocol) * Authentication failure: take the link down */ lcp_close(unit, "Authentication failed"); + status = EXIT_PEER_AUTH_FAILED; } /* @@ -492,7 +631,7 @@ auth_peer_success(unit, protocol, name, namelen) namelen = sizeof(peer_authname) - 1; BCOPY(name, peer_authname, namelen); peer_authname[namelen] = 0; - script_setenv("PEERNAME", peer_authname); + script_setenv("PEERNAME", peer_authname, 0); /* * If there is no more authentication still to be done, @@ -513,9 +652,12 @@ auth_withpeer_fail(unit, protocol) BZERO(passwd, MAXSECRETLEN); /* * 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. + * Some servers keep sending CHAP challenges, but there + * is no point in persisting without any way to get updated + * authentication secrets. */ + lcp_close(unit, "Failed to authenticate ourselves to peer"); + status = EXIT_AUTH_TOPEER_FAILED; } /* @@ -557,14 +699,22 @@ void np_up(unit, proto) int unit, proto; { + int tlim; + if (num_np_up == 0) { /* * At this point we consider that the link has come up successfully. */ - need_holdoff = 0; + status = EXIT_OK; + unsuccess = 0; + new_phase(PHASE_RUNNING); - if (idle_time_limit > 0) - TIMEOUT(check_idle, NULL, idle_time_limit); + if (idle_time_hook != 0) + tlim = (*idle_time_hook)(NULL); + else + tlim = idle_time_limit; + if (tlim > 0) + TIMEOUT(check_idle, NULL, tlim); /* * Set a timeout to close the connection once the maximum @@ -589,8 +739,10 @@ void np_down(unit, proto) int unit, proto; { - if (--num_np_up == 0 && idle_time_limit > 0) { + if (--num_np_up == 0) { UNTIMEOUT(check_idle, NULL); + UNTIMEOUT(connect_time_expired, NULL); + new_phase(PHASE_NETWORK); } } @@ -613,20 +765,28 @@ np_finished(unit, proto) */ static void check_idle(arg) - void *arg; + void *arg; { struct ppp_idle idle; time_t itime; + int tlim; if (!get_idle_time(0, &idle)) return; - itime = MIN(idle.xmit_idle, idle.recv_idle); - if (itime >= idle_time_limit) { + if (idle_time_hook != 0) { + tlim = idle_time_hook(&idle); + } else { + itime = MIN(idle.xmit_idle, idle.recv_idle); + tlim = idle_time_limit - itime; + } + if (tlim <= 0) { /* link is idle: shut it down. */ - info("Terminating connection due to lack of activity."); + notice("Terminating connection due to lack of activity."); lcp_close(0, "Link inactive"); + need_holdoff = 0; + status = EXIT_IDLE_TIMEOUT; } else { - TIMEOUT(check_idle, NULL, idle_time_limit - itime); + TIMEOUT(check_idle, NULL, tlim); } } @@ -639,6 +799,7 @@ connect_time_expired(arg) { info("Connect time expired"); lcp_close(0, "Connect time expired"); /* Close connection */ + status = EXIT_CONNECT_TIME; } /* @@ -659,13 +820,16 @@ auth_check_options() /* * If we have a default route, require the peer to authenticate - * unless the noauth option was given. + * unless the noauth option was given or the real user is root. */ - if (!auth_required && !allow_any_ip && have_route_to(0)) + if (!auth_required && !allow_any_ip && have_route_to(0) && !privileged) { auth_required = 1; + default_auth = 1; + } /* If authentication is required, ask peer for CHAP or PAP. */ if (auth_required) { + allow_any_ip = 0; if (!wo->neg_chap && !wo->neg_upap) { wo->neg_chap = 1; wo->neg_upap = 1; @@ -686,21 +850,24 @@ auth_check_options() our_name, 1, &lacks_ip); } - if (auth_required && !can_auth) { - if (explicit_remote) + if (auth_required && !can_auth && noauth_addrs == NULL) { + if (default_auth) { option_error( -"The remote system (%s) is required to authenticate itself but I", - remote_name); - else +"By default the remote system is required to authenticate itself"); option_error( -"The remote system is required to authenticate itself but I"); - - if (!lacks_ip) +"(because this system has a default route to the internet)"); + } else if (explicit_remote) option_error( -"couldn't find any suitable secret (password) for it to use to do so."); +"The remote system (%s) is required to authenticate itself", + remote_name); else option_error( -"couldn't find any secret (password) which would let it use an IP address."); +"The remote system is required to authenticate itself"); + option_error( +"but I couldn't find any suitable secret (password) for it to use to do so."); + if (lacks_ip) + option_error( +"(None of the available passwords would let it use an IP address.)"); exit(1); } @@ -720,8 +887,9 @@ auth_reset(unit) ao->neg_upap = !refuse_pap && (passwd[0] != 0 || get_pap_passwd(NULL)); ao->neg_chap = !refuse_chap - && have_chap_secret(user, (explicit_remote? remote_name: NULL), - 0, NULL); + && (passwd[0] != 0 + || have_chap_secret(user, (explicit_remote? remote_name: NULL), + 0, NULL)); if (go->neg_upap && !uselogin && !have_pap_secret(NULL)) go->neg_upap = 0; @@ -744,66 +912,91 @@ auth_reset(unit) * In either case, msg points to an appropriate message. */ int -check_passwd(unit, auser, userlen, apasswd, passwdlen, msg, msglen) +check_passwd(unit, auser, userlen, apasswd, passwdlen, msg) int unit; char *auser; int userlen; char *apasswd; int passwdlen; char **msg; - int *msglen; { int ret; char *filename; FILE *f; - struct wordlist *addrs; + struct wordlist *addrs = NULL, *opts = NULL; char passwd[256], user[256]; char secret[MAXWORDLEN]; static int attempts = 0; /* * Make copies of apasswd and auser, then null-terminate them. + * If there are unprintable characters in the password, make + * them visible. */ - BCOPY(apasswd, passwd, passwdlen); - passwd[passwdlen] = '\0'; - BCOPY(auser, user, userlen); - user[userlen] = '\0'; - *msg = (char *) 0; + slprintf(passwd, sizeof(passwd), "%.*v", passwdlen, apasswd); + slprintf(user, sizeof(user), "%.*v", userlen, auser); + *msg = ""; + + /* + * Check if a plugin wants to handle this. + */ + if (pap_auth_hook) { + ret = (*pap_auth_hook)(user, passwd, msg, &addrs, &opts); + if (ret >= 0) { + if (ret) + set_allowed_addrs(unit, addrs, opts); + BZERO(passwd, sizeof(passwd)); + if (addrs != 0) + free_wordlist(addrs); + return ret? UPAP_AUTHACK: UPAP_AUTHNAK; + } + } /* * Open the file of pap secrets and scan for a suitable secret * for authenticating this user. */ filename = _PATH_UPAPFILE; - addrs = NULL; - ret = UPAP_AUTHACK; + addrs = opts = NULL; + ret = UPAP_AUTHNAK; f = fopen(filename, "r"); if (f == NULL) { error("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 && (cryptpap || strcmp(passwd, secret) != 0) - && strcmp(crypt(passwd, secret), secret) != 0)) { - warn("PAP authentication failure for %s", user); - ret = UPAP_AUTHNAK; + if (scan_authfile(f, user, our_name, secret, &addrs, &opts, filename) < 0) { + warn("no PAP secret found for %s", user); + } else { + /* + * If the secret is "@login", it means to check + * the password against the login database. + */ + int login_secret = strcmp(secret, "@login") == 0; + ret = UPAP_AUTHACK; + if (uselogin || login_secret) { + /* login option or secret is @login */ + ret = plogin(user, passwd, msg); + if (ret == UPAP_AUTHNAK) + warn("PAP login failure for %s", user); + else + used_login = 1; + } + if (secret[0] != 0 && !login_secret) { + /* password given in pap-secrets - must match */ + if ((cryptpap || strcmp(passwd, secret) != 0) + && strcmp(crypt(passwd, secret), secret) != 0) { + ret = UPAP_AUTHNAK; + warn("PAP authentication failure for %s", user); + } + } } fclose(f); } - if (uselogin && ret == UPAP_AUTHACK) { - ret = plogin(user, passwd, msg, msglen); - if (ret == UPAP_AUTHNAK) { - warn("PAP login failure for %s", user); - } - } - if (ret == UPAP_AUTHNAK) { - if (*msg == (char *) 0) + if (**msg == 0) *msg = "Login incorrect"; - *msglen = strlen(*msg); /* * XXX can we ever get here more than once?? * Frustrate passwd stealer programs. @@ -816,17 +1009,18 @@ check_passwd(unit, auser, userlen, apasswd, passwdlen, msg, msglen) } if (attempts > 3) sleep((u_int) (attempts - 3) * 5); - if (addrs != NULL) - free_wordlist(addrs); + if (opts != NULL) + free_wordlist(opts); } else { attempts = 0; /* Reset count */ - if (*msg == (char *) 0) + if (**msg == 0) *msg = "Login ok"; - *msglen = strlen(*msg); - set_allowed_addrs(unit, addrs); + set_allowed_addrs(unit, addrs, opts); } + if (addrs != NULL) + free_wordlist(addrs); BZERO(passwd, sizeof(passwd)); BZERO(secret, sizeof(secret)); @@ -838,63 +1032,65 @@ check_passwd(unit, auser, userlen, apasswd, passwdlen, msg, msglen) */ #ifdef USE_PAM -static char *PAM_username = ""; -static char *PAM_password = ""; - -#ifdef PAM_ESTABLISH_CRED /* new PAM defines :(^ */ -#define MY_PAM_STRERROR(err_code) (char *) pam_strerror(pamh,err_code) -#else -#define MY_PAM_STRERROR(err_code) (char *) pam_strerror(err_code) -#endif +/* Static variables used to communicate between the conversation function + * and the server_login function + */ +static char *PAM_username; +static char *PAM_password; +static int PAM_error = 0; +static pam_handle_t *pamh = NULL; + +/* PAM conversation function + * Here we assume (for now, at least) that echo on means login name, and + * echo off means password. + */ -static int pam_conv (int num_msg, - const struct pam_message **msg, - struct pam_response **resp, - void *appdata_ptr) +static int PAM_conv (int num_msg, const struct pam_message **msg, + struct pam_response **resp, void *appdata_ptr) { - int count = 0, replies = 0; + int replies = 0; struct pam_response *reply = NULL; - int size = 0; - - for (count = 0; count < num_msg; count++) - { - size += sizeof (struct pam_response); - reply = realloc (reply, size); /* ANSI: is malloc() if reply==NULL */ - if (!reply) - return PAM_CONV_ERR; - - switch (msg[count]->msg_style) - { - case PAM_PROMPT_ECHO_ON: - reply[replies].resp_retcode = PAM_SUCCESS; - reply[replies++].resp = strdup(PAM_username); /* never NULL */ - break; - - case PAM_PROMPT_ECHO_OFF: - reply[replies].resp_retcode = PAM_SUCCESS; - reply[replies++].resp = strdup(PAM_password); /* never NULL */ - break; - - case PAM_TEXT_INFO: - reply[replies].resp_retcode = PAM_SUCCESS; - reply[replies++].resp = NULL; - break; - - case PAM_ERROR_MSG: - default: - free (reply); - return PAM_CONV_ERR; - } - } - - if (resp) - *resp = reply; - else - free (reply); +#define COPY_STRING(s) (s) ? strdup(s) : NULL + + reply = malloc(sizeof(struct pam_response) * num_msg); + if (!reply) return PAM_CONV_ERR; + + for (replies = 0; replies < num_msg; replies++) { + switch (msg[replies]->msg_style) { + case PAM_PROMPT_ECHO_ON: + reply[replies].resp_retcode = PAM_SUCCESS; + reply[replies].resp = COPY_STRING(PAM_username); + /* PAM frees resp */ + break; + case PAM_PROMPT_ECHO_OFF: + reply[replies].resp_retcode = PAM_SUCCESS; + reply[replies].resp = COPY_STRING(PAM_password); + /* PAM frees resp */ + break; + case PAM_TEXT_INFO: + /* fall through */ + case PAM_ERROR_MSG: + /* ignore it, but pam still wants a NULL response... */ + reply[replies].resp_retcode = PAM_SUCCESS; + reply[replies].resp = NULL; + break; + default: + /* Must be an error of some sort... */ + free (reply); + PAM_error = 1; + return PAM_CONV_ERR; + } + } + *resp = reply; return PAM_SUCCESS; } -#endif + +static struct pam_conv PAM_conversation = { + &PAM_conv, + NULL +}; +#endif /* USE_PAM */ /* * plogin - Check the user name and password against the system @@ -907,74 +1103,63 @@ static int pam_conv (int num_msg, */ static int -plogin(user, passwd, msg, msglen) +plogin(user, passwd, msg) char *user; char *passwd; char **msg; - int *msglen; { + char *tty; #ifdef USE_PAM - - struct pam_conv pam_conversation; - pam_handle_t *pamh; int pam_error; -/* - * Fill the pam_conversion structure - */ - memset (&pam_conversation, '\0', sizeof (struct pam_conv)); - pam_conversation.conv = &pam_conv; - - pam_error = pam_start ("ppp", user, &pam_conversation, &pamh); + pam_error = pam_start ("ppp", user, &PAM_conversation, &pamh); if (pam_error != PAM_SUCCESS) { - *msg = MY_PAM_STRERROR (pam_error); + *msg = (char *) pam_strerror (pamh, pam_error); + reopen_log(); return UPAP_AUTHNAK; } -/* - * Define the fields for the credintial validation - */ - (void) pam_set_item (pamh, PAM_TTY, devnam); + /* + * Define the fields for the credential validation + */ + PAM_username = user; PAM_password = passwd; -/* - * Validate the user - */ + PAM_error = 0; + pam_set_item (pamh, PAM_TTY, devnam); /* this might be useful to some modules */ + + /* + * Validate the user + */ pam_error = pam_authenticate (pamh, PAM_SILENT); - if (pam_error == PAM_SUCCESS) { + if (pam_error == PAM_SUCCESS && !PAM_error) { pam_error = pam_acct_mgmt (pamh, PAM_SILENT); - - /* start a session for this user. Session closed when link ends. */ - if (pam_error == PAM_SUCCESS) - (void) pam_open_session (pamh, PAM_SILENT); + if (pam_error == PAM_SUCCESS) + pam_open_session (pamh, PAM_SILENT); } - *msg = MY_PAM_STRERROR (pam_error); - - PAM_username = - PAM_password = ""; -/* - * Clean up the mess - */ - (void) pam_end (pamh, pam_error); + *msg = (char *) pam_strerror (pamh, pam_error); + /* + * Clean up the mess + */ + reopen_log(); /* apparently the PAM stuff does closelog() */ + PAM_username = NULL; + PAM_password = NULL; if (pam_error != PAM_SUCCESS) return UPAP_AUTHNAK; +#else /* #ifdef USE_PAM */ + /* * Use the non-PAM methods directly */ -#else /* #ifdef USE_PAM */ - - struct passwd *pw; - char *tty; #ifdef HAS_SHADOW struct spwd *spwd; struct spwd *getspnam(); - long now; #endif + struct passwd *pw = getpwnam(user); - pw = getpwnam(user); endpwent(); if (pw == NULL) return (UPAP_AUTHNAK); @@ -982,34 +1167,29 @@ plogin(user, passwd, msg, msglen) #ifdef HAS_SHADOW spwd = getspnam(user); endspent(); - if (spwd == NULL) - return UPAP_AUTHNAK; - - /* check the age of the password entry */ - now = time(NULL) / 86400L; - - if ((spwd->sp_expire > 0 && now >= spwd->sp_expire) - || ((spwd->sp_max >= 0 && spwd->sp_max < 10000) - && spwd->sp_lstchg >= 0 - && now >= spwd->sp_lstchg + spwd->sp_max)) { - warn("Password for %s has expired", user); - return (UPAP_AUTHNAK); + if (spwd) { + /* check the age of the password entry */ + long now = time(NULL) / 86400L; + + if ((spwd->sp_expire > 0 && now >= spwd->sp_expire) + || ((spwd->sp_max >= 0 && spwd->sp_max < 10000) + && spwd->sp_lstchg >= 0 + && now >= spwd->sp_lstchg + spwd->sp_max)) { + warn("Password for %s has expired", user); + return (UPAP_AUTHNAK); + } + pw->pw_passwd = spwd->sp_pwdp; } - pw->pw_passwd = spwd->sp_pwdp; #endif /* * If no passwd, don't let them login. */ - if (pw->pw_passwd == NULL || *pw->pw_passwd == '\0' + if (pw->pw_passwd == NULL || strlen(pw->pw_passwd) < 2 || strcmp(crypt(passwd, pw->pw_passwd), pw->pw_passwd) != 0) return (UPAP_AUTHNAK); - /* These functions are not enabled for PAM. The reason for this is that */ - /* there is not necessarily a "passwd" entry for this user. That is */ - /* real purpose of 'PAM' -- to virtualize the account data from the */ - /* application. If you want to do the same thing, write the entry in */ - /* the 'session' hook. */ +#endif /* #ifdef USE_PAM */ /* * Write a wtmp entry for this user. @@ -1020,8 +1200,8 @@ plogin(user, passwd, msg, msglen) tty += 5; logwtmp(tty, user, remote_name); /* Add wtmp login entry */ -#if defined(_PATH_LASTLOG) - { +#if defined(_PATH_LASTLOG) && !defined(USE_PAM) + if (pw != (struct passwd *)NULL) { struct lastlog ll; int fd; @@ -1029,14 +1209,12 @@ plogin(user, passwd, msg, msglen) (void)lseek(fd, (off_t)(pw->pw_uid * sizeof(ll)), SEEK_SET); memset((void *)&ll, 0, sizeof(ll)); (void)time(&ll.ll_time); - (void)strlcpy(ll.ll_line, tty, sizeof(ll.ll_line)); + (void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line)); (void)write(fd, (char *)&ll, sizeof(ll)); (void)close(fd); } } -#endif - -#endif /* #ifdef USE_PAM */ +#endif /* _PATH_LASTLOG and not USE_PAM */ info("user %s logged in", user); logged_in = 1; @@ -1051,33 +1229,23 @@ static void plogout() { #ifdef USE_PAM - struct pam_conv pam_conversation; - pam_handle_t *pamh; int pam_error; -/* - * Fill the pam_conversion structure. The PAM specification states that the - * session must be able to be closed by a totally different handle from which - * it was created. Hold the PAM group to their own specification! - */ - memset (&pam_conversation, '\0', sizeof (struct pam_conv)); - pam_conversation.conv = &pam_conv; - - pam_error = pam_start ("ppp", user, &pam_conversation, &pamh); - if (pam_error == PAM_SUCCESS) { - (void) pam_set_item (pamh, PAM_TTY, devnam); - (void) pam_close_session (pamh, PAM_SILENT); - (void) pam_end (pamh, PAM_SUCCESS); - } -#else + if (pamh != NULL) { + pam_error = pam_close_session (pamh, PAM_SILENT); + pam_end (pamh, pam_error); + pamh = NULL; + } + /* Apparently the pam stuff does closelog(). */ + reopen_log(); +#else /* ! USE_PAM */ char *tty; tty = devnam; if (strncmp(tty, "/dev/", 5) == 0) tty += 5; logwtmp(tty, "", ""); /* Wipe out utmp logout entry */ -#endif - +#endif /* ! USE_PAM */ logged_in = 0; } @@ -1094,30 +1262,40 @@ null_login(unit) char *filename; FILE *f; int i, ret; - struct wordlist *addrs; + struct wordlist *addrs, *opts; char secret[MAXWORDLEN]; + /* + * Check if a plugin wants to handle this. + */ + ret = -1; + if (null_auth_hook) + ret = (*null_auth_hook)(&addrs, &opts); + /* * Open the file of pap 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); + if (ret <= 0) { + 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; - BZERO(secret, sizeof(secret)); + i = scan_authfile(f, "", our_name, secret, &addrs, &opts, filename); + ret = i >= 0 && secret[0] == 0; + BZERO(secret, sizeof(secret)); + fclose(f); + } if (ret) - set_allowed_addrs(unit, addrs); - else + set_allowed_addrs(unit, addrs, opts); + else if (opts != 0) + free_wordlist(opts); + if (addrs != 0) free_wordlist(addrs); - fclose(f); return ret; } @@ -1135,18 +1313,25 @@ get_pap_passwd(passwd) char *filename; FILE *f; int ret; - struct wordlist *addrs; char secret[MAXWORDLEN]; + /* + * Check whether a plugin wants to supply this. + */ + if (pap_passwd_hook) { + ret = (*pap_passwd_hook)(user, passwd); + if (ret >= 0) + return ret; + } + filename = _PATH_UPAPFILE; - addrs = NULL; f = fopen(filename, "r"); if (f == NULL) return 0; check_access(f, filename); ret = scan_authfile(f, user, (remote_name[0]? remote_name: NULL), - secret, NULL, filename); + secret, NULL, NULL, filename); fclose(f); if (ret < 0) return 0; @@ -1170,13 +1355,20 @@ have_pap_secret(lacks_ipp) char *filename; struct wordlist *addrs; + /* let the plugin decide, if there is one */ + if (pap_check_hook) { + ret = (*pap_check_hook)(); + if (ret >= 0) + return ret; + } + filename = _PATH_UPAPFILE; f = fopen(filename, "r"); if (f == NULL) return 0; ret = scan_authfile(f, (explicit_remote? remote_name: NULL), our_name, - NULL, &addrs, filename); + NULL, &addrs, NULL, filename); fclose(f); if (ret >= 0 && !some_ip_ok(addrs)) { if (lacks_ipp != 0) @@ -1218,7 +1410,7 @@ have_chap_secret(client, server, need_ip, lacks_ipp) else if (server != NULL && server[0] == 0) server = NULL; - ret = scan_authfile(f, client, server, NULL, &addrs, filename); + ret = scan_authfile(f, client, server, NULL, &addrs, NULL, filename); fclose(f); if (ret >= 0 && need_ip && !some_ip_ok(addrs)) { if (lacks_ipp != 0) @@ -1238,38 +1430,46 @@ have_chap_secret(client, server, need_ip, lacks_ipp) * (We could be either client or server). */ int -get_secret(unit, client, server, secret, secret_len, save_addrs) +get_secret(unit, client, server, secret, secret_len, am_server) int unit; char *client; char *server; char *secret; int *secret_len; - int save_addrs; + int am_server; { FILE *f; int ret, len; char *filename; - struct wordlist *addrs; + struct wordlist *addrs, *opts; char secbuf[MAXWORDLEN]; - filename = _PATH_CHAPFILE; - addrs = NULL; - secbuf[0] = 0; + if (!am_server && passwd[0] != 0) { + strlcpy(secbuf, passwd, sizeof(secbuf)); + } else { + filename = _PATH_CHAPFILE; + addrs = NULL; + secbuf[0] = 0; + + f = fopen(filename, "r"); + if (f == NULL) { + error("Can't open chap secret file %s: %m", filename); + return 0; + } + check_access(f, filename); - f = fopen(filename, "r"); - if (f == NULL) { - error("Can't open chap secret file %s: %m", filename); - return 0; + ret = scan_authfile(f, client, server, secbuf, &addrs, &opts, filename); + fclose(f); + if (ret < 0) + return 0; + + if (am_server) + set_allowed_addrs(unit, addrs, opts); + else if (opts != 0) + free_wordlist(opts); + if (addrs != 0) + free_wordlist(addrs); } - check_access(f, filename); - - ret = scan_authfile(f, client, server, secbuf, &addrs, filename); - fclose(f); - if (ret < 0) - return 0; - - if (save_addrs) - set_allowed_addrs(unit, addrs); len = strlen(secbuf); if (len > MAXSECRETLEN) { @@ -1285,34 +1485,47 @@ get_secret(unit, client, server, secret, secret_len, save_addrs) /* * set_allowed_addrs() - set the list of allowed addresses. + * Also looks for `--' indicating options to apply for this peer + * and leaves the following words in extra_options. */ static void -set_allowed_addrs(unit, addrs) +set_allowed_addrs(unit, addrs, opts) int unit; struct wordlist *addrs; + struct wordlist *opts; { - int n = 0; - struct wordlist *ap; + int n; + struct wordlist *ap, **plink; struct permitted_ip *ip; char *ptr_word, *ptr_mask; struct hostent *hp; struct netent *np; - u_int32_t a, mask, ah; + u_int32_t a, mask, ah, offset; struct ipcp_options *wo = &ipcp_wantoptions[unit]; u_int32_t suggested_ip = 0; if (addresses[unit] != NULL) free(addresses[unit]); addresses[unit] = NULL; + if (extra_options != NULL) + free_wordlist(extra_options); + extra_options = opts; - for (ap = addrs; ap != NULL; ap = ap->next) - ++n; + /* + * Count the number of IP addresses given. + */ + n = wordlist_count(addrs) + wordlist_count(noauth_addrs); if (n == 0) return; ip = (struct permitted_ip *) malloc((n + 1) * sizeof(struct permitted_ip)); if (ip == 0) return; + /* temporarily append the noauth_addrs list to addrs */ + for (plink = &addrs; *plink != NULL; plink = &(*plink)->next) + ; + *plink = noauth_addrs; + n = 0; for (ap = addrs; ap != NULL; ap = ap->next) { /* "-" means no addresses authorized, "*" means any address allowed */ @@ -1333,18 +1546,29 @@ set_allowed_addrs(unit, addrs) } mask = ~ (u_int32_t) 0; + offset = 0; ptr_mask = strchr (ptr_word, '/'); if (ptr_mask != NULL) { int bit_count; + char *endp; - bit_count = (int) strtol (ptr_mask+1, (char **) 0, 10); + bit_count = (int) strtol (ptr_mask+1, &endp, 10); if (bit_count <= 0 || bit_count > 32) { warn("invalid address length %v in auth. address list", - ptr_mask); + ptr_mask+1); + continue; + } + bit_count = 32 - bit_count; /* # bits in host part */ + if (*endp == '+') { + offset = ifunit + 1; + ++endp; + } + if (*endp != 0) { + warn("invalid address length syntax: %v", ptr_mask+1); continue; } *ptr_mask = '\0'; - mask <<= 32 - bit_count; + mask <<= bit_count; } hp = gethostbyname(ptr_word); @@ -1372,16 +1596,26 @@ set_allowed_addrs(unit, addrs) if (ptr_mask != NULL) *ptr_mask = '/'; - if (a == (u_int32_t)-1L) + if (a == (u_int32_t)-1L) { warn("unknown host %s in auth. address list", ap->word); - else { - ip[n].mask = htonl(mask); - ip[n].base = a & ip[n].mask; - ++n; - if (~mask == 0 && suggested_ip == 0) - suggested_ip = a; + continue; + } + if (offset != 0) { + if (offset >= ~mask) { + warn("interface unit %d too large for subnet %v", + ifunit, ptr_word); + continue; + } + a = htonl((ntohl(a) & mask) + offset); + mask = ~(u_int32_t)0; } + ip[n].mask = htonl(mask); + ip[n].base = a & ip[n].mask; + ++n; + if (~mask == 0 && suggested_ip == 0) + suggested_ip = a; } + *plink = NULL; ip[n].permit = 0; /* make the last entry forbid all addresses */ ip[n].base = 0; /* to terminate the list */ @@ -1395,8 +1629,15 @@ set_allowed_addrs(unit, addrs) * which is a single host, then use that if we find one. */ if (suggested_ip != 0 - && (wo->hisaddr == 0 || !auth_ip_addr(unit, wo->hisaddr))) + && (wo->hisaddr == 0 || !auth_ip_addr(unit, wo->hisaddr))) { wo->hisaddr = suggested_ip; + /* + * Do we insist on this address? No, if there are other + * addresses authorized than the suggested one. + */ + if (n > 1) + wo->accept_remote = 1; + } } /* @@ -1408,12 +1649,20 @@ auth_ip_addr(unit, addr) int unit; u_int32_t addr; { - if (addresses[unit] == NULL) { - if (auth_required) - return 0; /* no addresses authorized */ - return allow_any_ip || !have_route_to(addr); + int ok; + + /* don't allow loopback or multicast address */ + if (bad_ip_adrs(addr)) + return 0; + + if (addresses[unit] != NULL) { + ok = ip_addr_check(addr, addresses[unit]); + if (ok >= 0) + return ok; } - return ip_addr_check(addr, addresses[unit]); + if (auth_required) + return 0; /* no addresses authorized */ + return allow_any_ip || privileged || !have_route_to(addr); } static int @@ -1421,10 +1670,6 @@ ip_addr_check(addr, addrs) u_int32_t addr; struct permitted_ip *addrs; { - /* don't allow loopback or multicast address */ - if (bad_ip_adrs(addr)) - return 0; - for (; ; ++addrs) if ((addr & addrs->mask) == addrs->base) return addrs->permit; @@ -1453,7 +1698,7 @@ some_ip_ok(addrs) struct wordlist *addrs; { for (; addrs != 0; addrs = addrs->next) { - if (strcmp(addrs->word, "-") == 0) + if (addrs->word[0] == '-') break; if (addrs->word[0] != '!') return 1; /* some IP address is allowed */ @@ -1486,29 +1731,34 @@ check_access(f, filename) * 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. + * Any following words on the line up to a "--" (i.e. address authorization + * info) are placed in a wordlist and returned in *addrs. Any + * following words (extra options) are placed in a wordlist and + * returned in *opts. * We assume secret is NULL or points to MAXWORDLEN bytes of space. */ static int -scan_authfile(f, client, server, secret, addrs, filename) +scan_authfile(f, client, server, secret, addrs, opts, filename) FILE *f; char *client; char *server; char *secret; struct wordlist **addrs; + struct wordlist **opts; char *filename; { int newline, xxx; int got_flag, best_flag; FILE *sf; - struct wordlist *ap, *addr_list, *alist, *alast; + struct wordlist *ap, *addr_list, *alist, **app; char word[MAXWORDLEN]; char atfile[MAXWORDLEN]; char lsecret[MAXWORDLEN]; if (addrs != NULL) *addrs = NULL; + if (opts != NULL) + *opts = NULL; addr_list = NULL; if (!getword(f, word, &newline, filename)) return -1; /* file is empty??? */ @@ -1562,46 +1812,44 @@ scan_authfile(f, client, server, secret, addrs, filename) if (newline) continue; - /* - * Special syntax: @filename means read secret from file. - */ - if (word[0] == '@') { - strlcpy(atfile, word+1, sizeof(atfile)); - if ((sf = fopen(atfile, "r")) == NULL) { - warn("can't open indirect secret file %s", atfile); - continue; - } - check_access(sf, atfile); - if (!getword(sf, word, &xxx, atfile)) { - warn("no secret in indirect secret file %s", atfile); + if (secret != NULL) { + /* + * Special syntax: @/pathname means read secret from file. + */ + if (word[0] == '@' && word[1] == '/') { + strlcpy(atfile, word+1, sizeof(atfile)); + if ((sf = fopen(atfile, "r")) == NULL) { + warn("can't open indirect secret file %s", atfile); + continue; + } + check_access(sf, atfile); + if (!getword(sf, word, &xxx, atfile)) { + warn("no secret in indirect secret file %s", atfile); + fclose(sf); + continue; + } fclose(sf); - continue; } - fclose(sf); - } - if (secret != NULL) strlcpy(lsecret, word, sizeof(lsecret)); + } /* * Now read address authorization info and make a wordlist. */ - alist = alast = NULL; + app = &alist; for (;;) { if (!getword(f, word, &newline, filename) || newline) break; - ap = (struct wordlist *) malloc(sizeof(struct wordlist)); + ap = (struct wordlist *) + malloc(sizeof(struct wordlist) + strlen(word) + 1); if (ap == NULL) novm("authorized addresses"); - ap->next = NULL; - ap->word = strdup(word); - if (ap->word == NULL) - novm("authorized address"); - if (alist == NULL) - alist = ap; - else - alast->next = ap; - alast = ap; + ap->word = (char *) (ap + 1); + strcpy(ap->word, word); + *app = ap; + app = &ap->next; } + *app = NULL; /* * This is the best so far; remember it. @@ -1617,6 +1865,20 @@ scan_authfile(f, client, server, secret, addrs, filename) break; } + /* scan for a -- word indicating the start of options */ + for (app = &addr_list; (ap = *app) != NULL; app = &ap->next) + if (strcmp(ap->word, "--") == 0) + break; + /* ap = start of options */ + if (ap != NULL) { + ap = ap->next; /* first option */ + free(*app); /* free the "--" word */ + *app = NULL; /* terminate addr list */ + } + if (opts != NULL) + *opts = ap; + else if (ap != NULL) + free_wordlist(ap); if (addrs != NULL) *addrs = addr_list; else if (addr_list != NULL) @@ -1625,6 +1887,20 @@ scan_authfile(f, client, server, secret, addrs, filename) return best_flag; } +/* + * wordlist_count - return the number of items in a wordlist + */ +static int +wordlist_count(wp) + struct wordlist *wp; +{ + int n; + + for (n = 0; wp != NULL; wp = wp->next) + ++n; + return n; +} + /* * free_wordlist - release memory allocated for a wordlist. */