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Diffstat (limited to 'Linux-PAM/modules/pam_rhosts/pam_rhosts_auth.c')
-rw-r--r--Linux-PAM/modules/pam_rhosts/pam_rhosts_auth.c782
1 files changed, 0 insertions, 782 deletions
diff --git a/Linux-PAM/modules/pam_rhosts/pam_rhosts_auth.c b/Linux-PAM/modules/pam_rhosts/pam_rhosts_auth.c
deleted file mode 100644
index 48fdeced..00000000
--- a/Linux-PAM/modules/pam_rhosts/pam_rhosts_auth.c
+++ /dev/null
@@ -1,782 +0,0 @@
-/*----------------------------------------------------------------------
- * Modified for Linux-PAM by Al Longyear <longyear@netcom.com> 96/5/5
- * Modifications, Cristian Gafton 97/2/8
- * Modifications, Peter Allgeyer 97/3
- * Modifications (netgroups and fixes), Nicolai Langfeldt 97/3/21
- * Security fix: 97/10/2 - gethostbyname called repeatedly without care
- * Modification (added privategroup option) Andrew <morgan@transmeta.com>
- *----------------------------------------------------------------------
- * Copyright (c) 1983, 1993, 1994
- * The Regents of the University of California. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * This product includes software developed by the University of
- * California, Berkeley and its contributors.
- * 4. Neither the name of the University nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#include "config.h"
-
-#include <pwd.h>
-#include <grp.h>
-#include <ctype.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <syslog.h>
-#include <netdb.h>
-#include <stdio.h>
-#include <errno.h>
-#include <string.h>
-#include <unistd.h>
-#include <stdlib.h>
-#include <endian.h>
-#include <sys/file.h>
-#include <sys/time.h>
-#include <arpa/inet.h>
-#include <sys/param.h>
-#include <sys/socket.h>
-#include <sys/signal.h>
-#include <sys/stat.h>
-#ifdef HAVE_SYS_FSUID_H
-#include <sys/fsuid.h>
-#endif /* HAVE_SYS_FSUID_H */
-#ifdef HAVE_NET_IF_H
-#include <net/if.h>
-#endif
-#include <sys/types.h>
-#include <sys/uio.h>
-#include <netinet/in.h>
-
-#ifndef MAXDNAME
-#define MAXDNAME 256
-#endif
-
-#ifndef _PATH_HEQUIV
-#define _PATH_HEQUIV "/etc/hosts.equiv"
-#endif /* _PATH_HEQUIV */
-
-#define USER_RHOSTS_FILE "/.rhosts" /* prefixed by user's home dir */
-
-#define PAM_SM_AUTH /* only defines this management group */
-
-#include <security/pam_modules.h>
-#include <security/_pam_macros.h>
-#include <security/pam_modutil.h>
-#include <security/pam_ext.h>
-
-/*
- * Options for this module
- */
-
-struct _options {
- int opt_no_hosts_equiv;
- int opt_hosts_equiv_rootok;
- int opt_no_rhosts;
- int opt_debug;
- int opt_nowarn;
- int opt_disallow_null_authtok;
- int opt_silent;
- int opt_promiscuous;
- int opt_suppress;
- int opt_private_group;
- int opt_no_uid_check;
- const char *superuser;
- const char *last_error;
-};
-
-static void
-set_option (const pam_handle_t *pamh, struct _options *opts, const char *arg)
-{
- if (strcmp(arg, "no_hosts_equiv") == 0) {
- opts->opt_no_hosts_equiv = 1;
- return;
- }
-
- if (strcmp(arg, "hosts_equiv_rootok") == 0) {
- opts->opt_hosts_equiv_rootok = 1;
- return;
- }
-
- if (strcmp(arg, "no_rhosts") == 0) {
- opts->opt_no_rhosts = 1;
- return;
- }
-
- if (strcmp(arg, "debug") == 0) {
- D(("debugging enabled"));
- opts->opt_debug = 1;
- return;
- }
-
- if (strcmp(arg, "no_warn") == 0) {
- opts->opt_nowarn = 1;
- return;
- }
-
- if (strcmp(arg, "promiscuous") == 0) {
- opts->opt_promiscuous = 1; /* used to permit '+' in ...hosts file */
- return;
- }
-
- if (strcmp(arg, "suppress") == 0) {
- opts->opt_suppress = 1; /* used to suppress failure warning message */
- return;
- }
-
- if (strcmp(arg, "privategroup") == 0) {
- opts->opt_private_group = 1; /* used to permit group write on .rhosts
- file if group has same name as owner */
- return;
- }
-
- if (strcmp(arg, "no_uid_check") == 0) {
- opts->opt_no_uid_check = 1; /* NIS optimization */
- return;
- }
-
- if (strncmp(arg, "superuser=", sizeof("superuser=")-1) == 0) {
- opts->superuser = arg+sizeof("superuser=")-1;
- return;
- }
- /*
- * All other options are ignored at the present time.
- */
- pam_syslog(pamh, LOG_WARNING, "unrecognized option '%s'", arg);
-}
-
-static void
-set_parameters (const pam_handle_t *pamh, struct _options *opts,
- int flags, int argc, const char **argv)
-{
- opts->opt_silent = flags & PAM_SILENT;
- opts->opt_disallow_null_authtok = flags & PAM_DISALLOW_NULL_AUTHTOK;
-
- while (argc-- > 0) {
- set_option (pamh, opts, *argv);
- ++argv;
- }
-}
-
-/*
- * Obtain the name of the remote host. Currently, this is simply by
- * requesting the contents of the PAM_RHOST item.
- */
-
-static int
-pam_get_rhost (pam_handle_t *pamh, const char **rhost)
-{
- int retval;
- const void *current;
-
- retval = pam_get_item (pamh, PAM_RHOST, &current);
- if (retval != PAM_SUCCESS)
- return retval;
-
- if (current == NULL) {
- return PAM_AUTH_ERR;
- }
- *rhost = current;
-
- return retval; /* pass on any error from conversation */
-}
-
-/*
- * Obtain the name of the remote user. Currently, this is simply by
- * requesting the contents of the PAM_RUSER item.
- */
-
-static int
-pam_get_ruser(pam_handle_t *pamh, const char **ruser)
-{
- int retval;
- const void *current;
-
- retval = pam_get_item (pamh, PAM_RUSER, &current);
- if (retval != PAM_SUCCESS) {
- return retval;
- }
-
- if (current == NULL) {
- return PAM_AUTH_ERR;
- }
- *ruser = current;
-
- return retval; /* pass on any error from conversation */
-}
-
-/*
- * Returns 1 if positive match, 0 if no match, -1 if negative match.
- */
-
-static int
-__icheckhost (pam_handle_t *pamh, struct _options *opts, u_int32_t raddr
- , register char *lhost, const char *rhost)
-{
- struct hostent *hp;
- u_int32_t laddr;
- int negate=1; /* Multiply return with this to get -1 instead of 1 */
- char **pp;
- const void *user;
-
- /* Check nis netgroup. We assume that pam has done all needed
- paranoia checking before we are handed the rhost */
- if (strncmp("+@",lhost,2) == 0)
- return(innetgr(&lhost[2],rhost,NULL,NULL));
-
- if (strncmp("-@",lhost,2) == 0)
- return(-innetgr(&lhost[2],rhost,NULL,NULL));
-
- /* -host */
- if (strncmp("-",lhost,1) == 0) {
- negate=-1;
- lhost++;
- } else if (strcmp("+",lhost) == 0) {
- (void) pam_get_item(pamh, PAM_USER, &user);
- D(("user %s has a `+' host entry", user));
- if (opts->opt_promiscuous)
- return (1); /* asking for trouble, but ok.. */
- /* If not promiscuous: handle as negative */
- return (-1);
- } else if (strncmp("+",lhost,1) == 0) {
- /* '+hostname' is supposed to be equivalent to 'hostname' */
- lhost++;
- }
-
-
- /* Try for raw ip address first. */
- if (isdigit(*lhost) && (int32_t)(laddr = inet_addr(lhost) != -1))
- return (negate*(! (raddr ^ laddr)));
-
- /* Better be a hostname. */
- hp = gethostbyname(lhost);
- if (hp == NULL)
- return (0);
-
- /* Spin through ip addresses. */
- for (pp = hp->h_addr_list; *pp; ++pp)
- if (!memcmp (&raddr, *pp, sizeof (u_int32_t)))
- return (negate);
-
- /* No match. */
- return (0);
-}
-
-/* Returns 1 on positive match, 0 on no match, -1 on negative match */
-
-static int
-__icheckuser (pam_handle_t *pamh, struct _options *opts,
- const char *luser, const char *ruser)
-{
- /*
- luser is user entry from .rhosts/hosts.equiv file
- ruser is user id on remote host
- */
- const void *user;
-
- /* [-+]@netgroup */
- if (strncmp("+@",luser,2) == 0)
- return (innetgr(&luser[2],NULL,ruser,NULL));
-
- if (strncmp("-@",luser,2) == 0)
- return (-innetgr(&luser[2],NULL,ruser,NULL));
-
- /* -user */
- if (strncmp("-",luser,1) == 0)
- return(-(strcmp(&luser[1],ruser) == 0));
-
- /* + */
- if (strcmp("+",luser) == 0) {
- (void) pam_get_item(pamh, PAM_USER, &user);
- pam_syslog(pamh, LOG_WARNING, "user %s has a `+' user entry",
- (const char *) user);
- if (opts->opt_promiscuous)
- return(1);
- /* If not promiscuous we handle it as a negative match */
- return(-1);
- }
-
- /* simple string match */
- return (strcmp(ruser, luser) == 0);
-}
-
-/*
- * Returns 1 for blank lines (or only comment lines) and 0 otherwise
- */
-
-static int __isempty(char *p)
-{
- while (*p && isspace(*p)) {
- ++p;
- }
-
- return (*p == '\0' || *p == '#') ? 1:0 ;
-}
-
-/*
- * Returns 0 if positive match, 1 if _not_ ok.
- */
-
-static int
-__ivaliduser (pam_handle_t *pamh, struct _options *opts,
- FILE *hostf, u_int32_t raddr,
- const char *luser, const char *ruser, const char *rhost)
-{
- register const char *user;
- register char *p;
- int hcheck, ucheck;
- int retval = 1;
-#ifdef HAVE_GETLINE
- char *buf=NULL;
- size_t buflen=0;
-
- while (getline(&buf,&buflen,hostf) > 0) {
-#else
- char buf[MAXHOSTNAMELEN + 128]; /* host + login */
-
- while (fgets(buf, sizeof(buf), hostf) != NULL) { /* hostf file line */
-#endif
- p = buf; /* from beginning of file.. */
-
- /* Skip empty or comment lines */
- if (__isempty(p)) {
- continue;
- }
-
- /* Skip lines that are too long. */
- if (strchr(p, '\n') == NULL) {
- int ch = getc(hostf);
-
- while (ch != '\n' && ch != EOF)
- ch = getc(hostf);
- continue;
- }
-
- /*
- * If there is a hostname at the start of the line. Set it to
- * lower case. A leading ' ' or '\t' indicates no hostname
- */
-
- for (;*p && !isspace(*p); ++p) {
- *p = tolower(*p);
- }
-
- /*
- * next we want to find the permitted name for the remote user
- */
-
- if (*p == ' ' || *p == '\t') {
-
- /* <nul> terminate hostname and skip spaces */
- for (*p++='\0'; *p && isspace(*p); ++p);
-
- user = p; /* this is the user's name */
- while (*p && !isspace(*p))
- ++p; /* find end of user's name */
- } else
- user = p;
-
- *p = '\0'; /* <nul> terminate username (+host?) */
-
- /* buf -> host(?) ; user -> username(?) */
-
- /* First check host part */
- hcheck=__icheckhost(pamh, opts, raddr, buf, rhost);
-
- if (hcheck<0)
- break;
-
- if (hcheck) {
- /* Then check user part */
- if (! (*user))
- user = luser;
-
- ucheck=__icheckuser(pamh, opts, user, ruser);
-
- /* Positive 'host user' match? */
- if (ucheck>0) {
- retval = 0;
- break;
- }
-
- /* Negative 'host -user' match? */
- if (ucheck<0)
- break;
-
- /* Neither, go on looking for match */
- }
- }
-#ifdef HAVE_GETLINE
- if(buf)free(buf);
-#endif
-
- return retval;
-}
-
-/*
- * New .rhosts strategy: We are passed an ip address. We spin through
- * hosts.equiv and .rhosts looking for a match. When the .rhosts only
- * has ip addresses, we don't have to trust a nameserver. When it
- * contains hostnames, we spin through the list of addresses the nameserver
- * gives us and look for a match.
- *
- * Returns 0 if ok, -1 if not ok.
- */
-
-static int
-pam_iruserok(pam_handle_t *pamh,
- struct _options *opts, u_int32_t raddr, int superuser,
- const char *ruser, const char *luser, const char *rhost)
-{
- const char *cp;
- struct stat sbuf;
- struct passwd *pwd;
- FILE *hostf;
- uid_t uid;
- int answer;
- char *fpath;
-
- if ((!superuser||opts->opt_hosts_equiv_rootok) && !opts->opt_no_hosts_equiv ) {
-
- /* try to open system hosts.equiv file */
- hostf = fopen (_PATH_HEQUIV, "r");
- if (hostf) {
- answer = __ivaliduser(pamh, opts, hostf, raddr, luser
- , ruser, rhost);
- (void) fclose(hostf);
- if (answer == 0)
- return 0; /* remote host is equivalent to localhost */
- } /* else {
- No hosts.equiv file on system.
- } */
- }
-
- if ( opts->opt_no_rhosts )
- return 1;
-
- /*
- * Identify user's local .rhosts file
- */
-
- pwd = pam_modutil_getpwnam(pamh, luser);
- if (pwd == NULL) {
- /*
- * luser is assumed to be valid because of an earlier check for uid = 0
- * we don't log this error twice. However, this shouldn't happen !
- * --cristiang
- */
- return(1);
- }
-
- if (asprintf (&fpath, "%s%s", pwd->pw_dir, USER_RHOSTS_FILE) < 0) {
- pam_syslog (pamh, LOG_ALERT, "Running out of memory");
- return 1;
- }
-
- /*
- * Change effective uid while _reading_ .rhosts. (not just
- * opening). If root and reading an NFS mounted file system,
- * can't read files that are 0600 as .rhosts files should be.
- */
-
- /* We are root, this will not fail */
-#ifdef __linux__
- /* If we are on linux the better way is setfsuid */
- uid = setfsuid(pwd->pw_uid);
- hostf = fopen(fpath, "r");
-#else
- uid = geteuid();
- (void) seteuid(pwd->pw_uid);
- hostf = fopen(fpath, "r");
-#endif
-
- if (hostf == NULL) {
- if (opts->opt_debug)
- pam_syslog(pamh, LOG_DEBUG, "Could not open %s: %m", fpath);
- answer = 1;
- goto exit_function;
- }
-
- /*
- * If not a regular file, or is owned by someone other than
- * user or root or if writeable by anyone but the owner, quit.
- */
-
- cp = NULL;
- if (lstat(fpath, &sbuf) < 0 || !S_ISREG(sbuf.st_mode))
- cp = ".rhosts not regular file";
- else if (fstat(fileno(hostf), &sbuf) < 0)
- cp = ".rhosts fstat failed";
- else if (sbuf.st_uid && sbuf.st_uid != pwd->pw_uid)
- cp = "bad .rhosts owner";
- else if (sbuf.st_mode & S_IWOTH)
- cp = ".rhosts writable by other!";
- else if (sbuf.st_mode & S_IWGRP) {
-
- /* private group caveat */
- if (opts->opt_private_group) {
- struct group *grp = pam_modutil_getgrgid(pamh, sbuf.st_gid);
-
- if (NULL == grp || NULL == grp->gr_name
- || strcmp(luser,grp->gr_name)) {
- cp = ".rhosts writable by public group";
- } else if (grp->gr_mem) {
- int gcount;
-
- /* require at most one member (luser) of this group */
- for (gcount=0; grp->gr_mem[gcount]; ++gcount) {
- if (strcmp(grp->gr_mem[gcount], luser)) {
- gcount = -1;
- break;
- }
- }
- if (gcount < 0) {
- cp = ".rhosts writable by other members of group";
- }
- }
- } else {
- cp = ".rhosts writable by group";
- }
-
- } /* It is _NOT_ safe to append an else here... Do so prior to
- * S_IWGRP check */
-
- /* If there were any problems, quit. */
- if (cp) {
- opts->last_error = cp;
- answer = 1;
- goto exit_function;
- }
-
- answer = __ivaliduser (pamh, opts, hostf, raddr, luser, ruser, rhost);
-
-exit_function:
- /*
- * Go here to exit after the fsuid/euid has been adjusted so that
- * they are reset before we exit.
- */
-
-#ifdef __linux__
- setfsuid(uid);
-#else
- (void)seteuid(uid);
-#endif
-
- free (fpath);
-
- if (hostf != NULL)
- (void) fclose(hostf);
-
- return answer;
-}
-
-static int
-pam_ruserok (pam_handle_t *pamh,
- struct _options *opts, const char *rhost, int superuser,
- const char *ruser, const char *luser)
-{
- struct hostent *hp;
- int answer = 1; /* default to failure */
- u_int32_t *addrs;
- int n, i;
-
- opts->last_error = (char *) 0;
- hp = gethostbyname(rhost); /* identify host */
-
- if (hp != NULL) {
- /* First of all check the address length */
- if (hp->h_length != 4) {
- pam_syslog(pamh, LOG_ALERT,
- "pam_rhosts module can't work with non-IPv4 addresses");
- return 1; /* not allowed */
- }
-
- /* loop though address list */
- for (n = 0; hp->h_addr_list[n]; n++);
- D(("rhosts: %d addresses", n));
-
- if (n) {
- addrs = calloc (n, hp->h_length);
- for (i = 0; i < n; i++)
- memcpy (addrs+i, hp->h_addr_list[i], hp->h_length);
-
- for (i = 0; i < n && answer; i++) {
- D(("rhosts: address %d is %04x", i, addrs[i]));
- answer = pam_iruserok(pamh, opts, addrs[i], superuser,
- ruser, luser, rhost);
- /* answer == 0 means success */
- }
-
- free (addrs);
- }
- }
-
- return answer;
-}
-
-/*
- * Internal function to do authentication
- */
-
-static int _pam_auth_rhosts (pam_handle_t *pamh,
- int flags,
- int argc,
- const char **argv)
-{
- int retval;
- const char *luser = NULL;
- const char *ruser = NULL, *rhost = NULL;
- struct _options opts;
- int as_root = 0;
-
- /*
- * Look at the options and set the flags accordingly.
- */
- memset (&opts, 0, sizeof (opts));
- set_parameters (pamh, &opts, flags, argc, argv);
- /*
- * Obtain the parameters for the various items
- */
- for (;;) { /* abuse loop to avoid goto */
-
- /* get the remotehost */
- D(("getting rhost"));
- retval = pam_get_rhost(pamh, &rhost);
- (void) pam_set_item(pamh, PAM_RHOST, rhost);
- if (retval != PAM_SUCCESS) {
- if (opts.opt_debug) {
- pam_syslog(pamh, LOG_DEBUG,
- "could not get the remote host name");
- }
- break;
- }
-
- /* get the remote user */
- D(("getting ruser"));
- retval = pam_get_ruser(pamh, &ruser);
- (void) pam_set_item(pamh, PAM_RUSER, ruser);
- if (retval != PAM_SUCCESS) {
- if (opts.opt_debug)
- pam_syslog(pamh, LOG_DEBUG,
- "could not get the remote username");
- break;
- }
-
- /* get the local user */
- D(("getting user"));
- retval = pam_get_user(pamh, &luser, NULL);
- if (retval != PAM_SUCCESS) {
- if (opts.opt_debug)
- pam_syslog(pamh, LOG_DEBUG,
- "could not determine name of local user");
- break;
- }
-
- if (opts.superuser && !strcmp(opts.superuser, luser)) {
- as_root = 1;
- }
-
- /* check if the luser uid == 0... --cristiang */
- if (! opts.opt_no_uid_check) {
- struct passwd *luser_pwd;
-
- luser_pwd = pam_modutil_getpwnam(pamh, luser);
- if (luser_pwd == NULL) {
- if (opts.opt_debug)
- pam_syslog(pamh, LOG_DEBUG,
- "user '%s' unknown to this system", luser);
- retval = PAM_AUTH_ERR;
- break;
- }
- if (luser_pwd->pw_uid == 0)
- as_root = 1;
- luser_pwd = NULL; /* forget */
- }
-/*
- * Validate the account information.
- */
- if (pam_ruserok (pamh, &opts, rhost, as_root, ruser, luser) != 0) {
- if ( !opts.opt_suppress ) {
- pam_syslog(pamh, LOG_WARNING, "denied to %s@%s as %s: %s",
- ruser, rhost, luser, (opts.last_error==NULL) ?
- "access not allowed":opts.last_error);
- }
- retval = PAM_AUTH_ERR;
- } else {
- pam_syslog(pamh, LOG_NOTICE, "allowed to %s@%s as %s",
- ruser, rhost, luser);
- }
- break;
- }
-
- return retval;
-}
-
-/* --- authentication management functions --- */
-
-PAM_EXTERN
-int pam_sm_authenticate (pam_handle_t *pamh,
- int flags,
- int argc,
- const char **argv)
-{
- int retval;
-
- if (sizeof(u_int32_t) != 4) {
- pam_syslog (pamh, LOG_ALERT,
- "pam_rhosts module can\'t work on this hardware (yet)");
- return PAM_AUTH_ERR;
- }
- sethostent(1);
- retval = _pam_auth_rhosts (pamh, flags, argc, argv);
- endhostent();
- return retval;
-}
-
-PAM_EXTERN int
-pam_sm_setcred (pam_handle_t *pamh UNUSED, int flags UNUSED,
- int argc UNUSED, const char **argv UNUSED)
-{
- return PAM_SUCCESS;
-}
-
-/* end of module definition */
-
-
-#ifdef PAM_STATIC
-
-/* static module data */
-
-struct pam_module _pam_rhosts_auth_modstruct = {
- "pam_rhosts_auth",
- pam_sm_authenticate,
- pam_sm_setcred,
- NULL,
- NULL,
- NULL,
- NULL,
-};
-
-#endif
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-18 13:15:32 +0000