libpam-chroot-0.9/0000755000175000017500000000000010070701630013502 5ustar jfsjfs00000000000000libpam-chroot-0.9/Makefile0000644000175000017500000000045310046030123015137 0ustar jfsjfs00000000000000# $Id: Makefile,v 1.1.1.1 2004/05/05 00:07:47 schmolli Exp $ CC=gcc CFLAGS=-fPIC -O2 -Wall -Werror -pedantic CPPFLAGS=-I. LDFLAGS=-x --shared -lpam OUT=pam_chroot.so all: $(OUT) %.so: %.o ld $(LDFLAGS) -o $@ $< clean: rm -f *.o $(OUT) install: install -s -o0 -g0 -m755 $(OUT) /lib/security libpam-chroot-0.9/CREDITS0000644000175000017500000000075110070700327014527 0ustar jfsjfs00000000000000This version of pam_chroot was originally written by Matthew Kirkwood (weejock@ferret.lmh.ox.ac.uk) and then heavily modified by Ed Schmollinger (schmolli@frozencrow.org). Bugs are likely attributable to Ed, and he's who you should send bug reports to. The following have contributed code and/or ideas: Heiko Hund - fix memory leaks, expanded user/group regex support John Newbigin - security checks for conf file & chroot directories libpam-chroot-0.9/LICENSE0000644000175000017500000004333510046030123014512 0ustar jfsjfs00000000000000This version of pam_chroot has been made available under the terms of the GNU General Public License version 2, or, at your option, any later version. GNU GENERAL PUBLIC LICENSE Version 2, June 1991 Copyright (C) 1989, 1991 Free Software Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. Preamble The licenses for most software are designed to take away your freedom to share and change it. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change free software--to make sure the software is free for all its users. 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If the program is interactive, make it output a short notice like this when it starts in an interactive mode: Gnomovision version 69, Copyright (C) year name of author Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. This is free software, and you are welcome to redistribute it under certain conditions; type `show c' for details. The hypothetical commands `show w' and `show c' should show the appropriate parts of the General Public License. Of course, the commands you use may be called something other than `show w' and `show c'; they could even be mouse-clicks or menu items--whatever suits your program. You should also get your employer (if you work as a programmer) or your school, if any, to sign a "copyright disclaimer" for the program, if necessary. Here is a sample; alter the names: Yoyodyne, Inc., hereby disclaims all copyright interest in the program `Gnomovision' (which makes passes at compilers) written by James Hacker. , 1 April 1989 Ty Coon, President of Vice This General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Library General Public License instead of this License. libpam-chroot-0.9/TROUBLESHOOTING0000644000175000017500000000625610046030123015720 0ustar jfsjfs00000000000000Troubleshooting chroots is usually hairy, which is why pam_chroot puts out so many syslog messages. This file contains a few things to check on if you're having problems. If you don't find the answer here, then you may also want to check the pam-list archives. Note that all of the following assumes that you have put pam_chroot into debug mode (add the "debug" option to the pam_chroot line in the appropriate /etc/pam.d file) and that syslogd is configured to put auth.debug messages in some known location (/var/log/messages, /var/adm/messages, /var/adm/syslog/syslog.log, etc.) Under normal operation, pam_chroot will output something similar to the following messages when it is in debug mode: Oct 17 08:38:23 nell pam_chroot[25932]: session: reading config file (/etc/security/chroot.conf) Oct 17 08:38:23 nell pam_chroot[25932]: session: expanded path "/chroot" -> "/chroot" Oct 17 08:38:23 nell pam_chroot[25932]: session: found chroot_dir "/chroot" for user "schmolli" Oct 17 08:38:23 nell pam_chroot[25932]: session: preparing to chroot() Oct 17 08:38:23 nell pam_chroot[25932]: session: chroot(/chroot) ok Oct 17 08:38:23 nell pam_chroot[25932]: session: returning success NOTE: the "preparing to chroot()" message is new as of pam_chroot-0.7 If something had gone wrong with the above session, you would have seen a message stating what went wrong, and probably a message stating that an error was being returned. PROBLEM: No pam_chroot syslog messages after the "calling chroot" message SOLUTION: This usually happens when the chroot() succeeds, but there is no syslogd socket listening inside the chroot. pam_chroot is still trying to syslog those messages, but syslogd isn't hearing them. You can fix this by "making syslogd work inside the chroot." The way you do that varies by OS. Check the man pages for syslogd. On linux: add "-a /chroot/dev/log" as an argument to syslogd in the appropriate init.d script. On solaris: add "-p /chroot/dev/log" as an argument to syslogd in the appropriate init.d script. PROBLEM: No pam_chroot messages at all SOLUTION: This usually indicates that the pam_chroot module is not being used at all. This might be because you did not add it to the appropriate /etc/pam.d file, or it might be that PAM is not being used at all. (For example, you might have set 'UsePAM no' in your /etc/ssh/sshd_config.) It might also be that syslogd is not running or is not configured to report auth.debug messages in the file that you're looking for them in. There are a multitude of reasons that PAM might not be being used, and they're usually application configuration issues, rather than issues with PAM itself. OpenSSH: Recent versions of OpenSSH require that the following be set in your sshd_config: ChallengeResponseAuthentication yes UsePAM yes If all else fails, you can use a process tracing tool (strace under linux, truss under solaris, or tusc under HP) to figure out what calls your application is making, what files it is reading, etc. That will usually provide you with a few clues. This is ugly and possibly time-consuming, but then again, it's not really very easy to debug somebody else's chroot problem over email. libpam-chroot-0.9/chroot.conf0000644000175000017500000000024110046030123015637 0ustar jfsjfs00000000000000# /etc/security/chroot.conf # format: # username chroot_dir #foo /home/foo # Or, if you've specified use_regex, # username_regex chroot_dir #^bar.* /home/bar libpam-chroot-0.9/options0000644000175000017500000000220210066433054015123 0ustar jfsjfs00000000000000debug - Output lots of extra debugging info via syslog no_warn - Do not print warning messages to STDOUT. (Equivalent to passing the PAM_SILENT flag.) use_first_pass, try_first_pass, use_mapped_pass - Nothing. no_chroot - Don't really chroot, but do everything else normally. use_regex - Treat the name field of the chroot.conf file as if it were a regular expression. use_ext_regex - Use extended regular expressions. Implies use_regex. use_groups - Allow "@group" syntax for name field in chroot.conf sec_checks - Check permissions and modes on conf files and chroot paths, return PAM_SESSION_ERR if bad ownership/perms are found. notfound=(success|failure) - Return PAM_SUCCESS or PAM_SESSION_ERR, respectively, if the chroot_dir for the current user cannot be determined. Default is to return PAM_SUCCESS. onerr=(succeed|fail) - Return PAM_SUCCESS or PAM_SESSION_ERR, respectively, if the chroot_dir for the current user cannot be determined. Default is to return PAM_SUCCESS. chroot_dir= - Specify the chroot_dir. Overrides anything that might be in the chroot.conf file. In fact, chroot.conf won't even be consulted. libpam-chroot-0.9/pam_chroot.c0000644000175000017500000005727210066433010016015 0ustar jfsjfs00000000000000/* * Linux-PAM session chroot()er * account, session, authentication * * $Id: pam_chroot.c,v 1.3 2004/06/24 02:01:44 schmolli Exp $ */ #include #include #include #include #include #include #include #include #include #include #include #include #define PAM_SM_AUTH #define PAM_SM_ACCOUNT #define PAM_SM_SESSION #include #include #define CONFIG "/etc/security/chroot.conf" #define LINELEN 1024 /* max length (bytes) of line in config file */ #define SCRATCH 32 /* max length (bytes) for scribble space */ #define MAX_GROUPS 64 /* maximum number of groups we handle */ /* defines for flags */ #define _PAM_OPTS_NOOPTS 0x0000 #define _PAM_OPTS_DEBUG 0x0001 #define _PAM_OPTS_SILENT 0x0002 #define _PAM_OPTS_NOTFOUNDFAILS 0x0004 #define _PAM_OPTS_NO_CHROOT 0x0008 #define _PAM_OPTS_USE_REGEX 0x0010 #define _PAM_OPTS_USE_EXT_REGEX 0x0030 /* includes _PAM_OPTS_USE_REGEX */ #define _PAM_OPTS_USE_GROUPS 0x0040 #define _PAM_OPTS_SECCHECKS 0x0080 /* defines for (internal) return values */ #define _PAM_CHROOT_INTERNALERR -2 #define _PAM_CHROOT_SYSERR -1 #define _PAM_CHROOT_OK 0 #define _PAM_CHROOT_USERNOTFOUND 1 #define _PAM_CHROOT_INCOMPLETE 2 struct _pam_opts { int16_t flags; /* combined option flags */ char* chroot_dir; /* where to chroot to */ char* conf; /* name of pam_chroot config file */ char* module; /* module currently being processed */ }; static void _pam_log(int err, const char *format, ...) { va_list args; va_start(args, format); openlog("pam_chroot", LOG_PID, LOG_AUTHPRIV); vsyslog(err, format, args); va_end(args); closelog(); } /* initialize opts to a standard known state */ int _pam_opts_init(struct _pam_opts* opts) { if(NULL == opts) { _pam_log(LOG_ERR, "%s: NULL opts pointer", __FUNCTION__); return _PAM_CHROOT_INTERNALERR; } opts->flags = _PAM_OPTS_NOOPTS; opts->chroot_dir = NULL; opts->conf = x_strdup(CONFIG); if(NULL == opts->conf) { _pam_log(LOG_ERR, "strdup: %s", strerror(errno)); return _PAM_CHROOT_SYSERR; } return _PAM_CHROOT_OK; } /* configure opts per the passed flags and cmd line args */ int _pam_opts_config(struct _pam_opts* opts, int flags, int argc, const char** argv) { int i; if(NULL == opts) { _pam_log(LOG_ERR, "%s: NULL opts pointer", __FUNCTION__); return _PAM_CHROOT_INTERNALERR; } if(flags & PAM_SILENT) { opts->flags = opts->flags | _PAM_OPTS_SILENT; } if((flags & PAM_DISALLOW_NULL_AUTHTOK) && (!strcmp(opts->module, "auth") || !strcmp(opts->module, "account"))) { opts->flags = opts->flags | _PAM_OPTS_NOTFOUNDFAILS; } /* parse command line args */ for(i = 0; i < argc; i++) { if(!strcmp(argv[i], "debug")) { opts->flags = opts->flags | _PAM_OPTS_DEBUG; } else if(!strcmp(argv[i], "no_warn")) { opts->flags = opts->flags | _PAM_OPTS_SILENT; } else if(!strcmp(argv[i], "use_first_pass") || !strcmp(argv[i], "try_first_pass") || !strcmp(argv[i], "use_mapped_pass")) { /* ignore these, pam_chroot doesn't care about passwds */ } else if(!strcmp(argv[i], "no_chroot")) { opts->flags = opts->flags | _PAM_OPTS_NO_CHROOT; } else if(!strcmp(argv[i], "use_regex")) { opts->flags = opts->flags | _PAM_OPTS_USE_REGEX; } else if(!strcmp(argv[i], "use_ext_regex")) { opts->flags = opts->flags | _PAM_OPTS_USE_EXT_REGEX; } else if(!strcmp(argv[i], "use_groups")) { opts->flags = opts->flags | _PAM_OPTS_USE_GROUPS; } else if(!strcmp(argv[i], "sec_checks")) { opts->flags = opts->flags | _PAM_OPTS_SECCHECKS; } else if(!strncmp(argv[i], "notfound=", 9)) { if(!strcmp(argv[i] + 9, "success")) { opts->flags = opts->flags & (~_PAM_OPTS_NOTFOUNDFAILS); } else if(!strcmp(argv[i] + 9, "failure")) { opts->flags = opts->flags | _PAM_OPTS_NOTFOUNDFAILS; } else { _pam_log(LOG_ERR, "bad config option: \"%s\"", argv[i]); } } else if(!strncmp(argv[i], "onerr=", 6)) { if(!strcmp(argv[i] + 6, "succeed")) { opts->flags = opts->flags & (~_PAM_OPTS_NOTFOUNDFAILS); } else if(!strcmp(argv[i] + 9, "fail")) { opts->flags = opts->flags | _PAM_OPTS_NOTFOUNDFAILS; } else { _pam_log(LOG_ERR, "bad config option: \"%s\"", argv[i]); } } else if(!strncmp(argv[i], "chroot_dir=", 11)) { if(*(argv[i] + 11) == '\0') { _pam_log(LOG_ERR, "bad config option: \"%s\": specify a directory", argv[i]); } else if(NULL != opts->chroot_dir) { _pam_log(LOG_ERR, "bad config option: \"%s\": chroot dir already set", argv[i]); } else { opts->chroot_dir = x_strdup(argv[i] + 11); if(NULL == opts->chroot_dir) { _pam_log(LOG_ERR, "strdup: %s", strerror(errno)); } } } else { _pam_log(LOG_ERR, "unrecognized config option: \"%s\"", argv[i]); } } return _PAM_CHROOT_OK; } /* free the allocated memory of a struct _pam_opts */ int _pam_opts_free(struct _pam_opts* opts) { if(NULL == opts) { _pam_log(LOG_ERR, "%s: NULL opts pointer", __FUNCTION__); } _pam_drop(opts->chroot_dir); _pam_drop(opts->conf); return _PAM_CHROOT_OK; } /* if the system doesn't have getgrouplist(), then I have to do it myself */ #ifndef HAVE_GETGROUPLIST #define _PAM_GETUGROUPS _pam_getugroups /* *user is the user to collect info on * gid is a gid to include in the grplist * *grps is the array of gid_t to return the grplist in (if not NULL) * *ngrps is the max number of gid_t to return in grplist AND where to * store the actual number of gid_t returned * * return -1 if *ngrps is too small */ int _pam_getugroups(const char *user, gid_t gid, gid_t *grps, int *ngrps) { struct group *grp; int gcount = 0; char **uptr; if(NULL == user || NULL == ngrps) { return -1; } if(0 > *ngrps || 0 > gid) { return -1; } if(gcount < *ngrps) { if(NULL != grps) { grps[gcount] = gid; } gcount++; } else { *ngrps = gcount; endgrent(); return -1; } setgrent(); while(NULL != (grp = getgrent())) { if(NULL == grp->gr_name || NULL == grp->gr_mem) { continue; } /* don't add gids more than once, don't do this check if grps is NULL */ /* yes, that's incorrect, but it's harder to do it correctly, and since * we're just counting, for the NULL case, it's unlikely to cause a * real problem in reasonable circumstances */ if(NULL != grps) { int i; for(i = 0 ; i < gcount ; i++) { if(grp->gr_gid == grps[i]) { i = -1; break; } } if(-1 == i) { continue; } } for(uptr = grp->gr_mem ; NULL != *uptr ; uptr++) { if(0 != strcmp(*uptr, user)) { continue; } if(gcount < *ngrps) { if(NULL != grps) { grps[gcount] = grp->gr_gid; } gcount++; } else { *ngrps = gcount; endgrent(); return -1; } } } endgrent(); *ngrps = gcount; return gcount; } #else #define _PAM_GETUGROUPS getgrouplist #endif /* generate a list of group names from a list of gids */ char** _pam_get_groups(const char* user, struct _pam_opts* opts) { int i, ret, ngroups = MAX_GROUPS; struct group* grp; struct passwd* pwd; gid_t *gids; char **groups; char scratch[SCRATCH]; pwd = getpwnam(user); if(pwd == NULL) { _pam_log(LOG_ERR, "%s: user \"%s\" not a valid username", opts->module, user); return NULL; } /* get a list of all the gids for this username */ _PAM_GETUGROUPS(pwd->pw_name, pwd->pw_gid, NULL, &ngroups); if(0 >= ngroups) { _pam_log(LOG_ERR, "%s: error fetching groups for user \"%s\"", opts->module, user); return NULL; } gids = (gid_t*) malloc(ngroups*sizeof(gid_t)); if(NULL == gids) { _pam_log(LOG_ERR, "%s: %s: malloc: %s", opts->module, __FUNCTION__, strerror(errno)); return NULL; } ret = _PAM_GETUGROUPS(pwd->pw_name, pwd->pw_gid, gids, &ngroups); if(-1 == ret) { _pam_log(LOG_WARNING, "%s: %s: _PAM_GETUGROUPS found more gids on second run", opts->module, __FUNCTION__); } if(0 >= ngroups) { _pam_log(LOG_ERR, "%s: %s: _PAM_GETUGROUPS returned no groups for user \"%s\"", opts->module, __FUNCTION__, user); _pam_drop(gids); return NULL; } /* resolve gids into grpnams */ groups = (char**)malloc((ngroups+1)*sizeof(char*)); if(NULL == groups) { _pam_log(LOG_ERR, "%s: %s: malloc: %s", opts->module, __FUNCTION__, strerror(errno)); _pam_drop(gids); return NULL; } for(i = 0; i < ngroups ; i++) { grp = getgrgid(gids[i]); if(NULL == grp) { _pam_log(LOG_DEBUG, "%s: no grnam for gid %d", opts->module, gids[i]); snprintf(scratch, SCRATCH, "%d", gids[i]); groups[i] = x_strdup(scratch); } else { groups[i] = x_strdup(grp->gr_name); } } groups[i] = NULL; _pam_drop(gids); return groups; } /* helper function to free group list */ void _pam_free_groups(char **groups) { int i = 0; if(NULL == groups) { return; } while(NULL != groups[i]) { _pam_drop(groups[i]); i++; } _pam_drop(groups); } /* verify that the arguement path is root owned and not writable by * group or other * return 0 if ok, 1 if not, -1 on system error */ int _pam_check_path_perms(char *path, struct _pam_opts* opts) { int i = 0, rslt = 0; char save; struct stat st; path = x_strdup(path); if(NULL == path) { _pam_log(LOG_ERR, "strdup: %s", strerror(errno)); return -1; } while('\0' != path[i]) { if('/' == path[i]) { save = path[i + 1]; path[i + 1] = '\0'; if(-1 == stat(path, &st)) { _pam_log(LOG_ERR, "stat(%s): %s", path, strerror(errno)); rslt = -1; break; } if((0 != st.st_uid) || (st.st_mode & (S_IWGRP | S_IWOTH))) { _pam_log(LOG_ERR, "bad ownership/perms on %s", path); rslt = 1; break; } path[i + 1] = save; } i++; } if((NULL != opts) && (opts->flags & _PAM_OPTS_DEBUG)) { _pam_log(LOG_NOTICE, "%s: ownership/perms ok on %s", opts->module, path); } _pam_drop(path); return rslt; } /* expand chroot path */ /* path - string to expand * user - username, for %u expansion * grp - group, for %g expansion * match - name entry that was matched * matchptr - array of regmatch_t containing matched substrings (assume * at least 10 items in array) */ char* _pam_expand_chroot_dir(const char* path, const char* user, const char* grp, const char* match, regmatch_t* matchptr, struct _pam_opts* opts) { char ref; /* ref char */ char *pos; /* ref position */ char *exp; /* expanded path */ int reflen; /* length of expanded path */ int refnum; /* number of regex backreference */ int offset = 0; /* search offset */ if(NULL == path || NULL == user || NULL == opts) { return NULL; } else if(NULL == grp && (opts->flags & _PAM_OPTS_USE_GROUPS)) { return NULL; } exp = x_strdup(path); if(NULL == exp) { _pam_log(LOG_ERR, "%s: strdup: %s", opts->module, strerror(errno)); return NULL; } while(NULL != (pos = strchr(exp + offset, '%'))) { offset = pos - exp; /* save for post-realloc */ reflen = 0; ref = *(pos + 1); if('u' == tolower(ref)) { /* %u found */ reflen = strlen(user); exp = (char*) realloc(exp, strlen(exp) + reflen - 1); if(NULL == exp) { break; } pos = exp + offset; memmove(pos + reflen, pos + 2, strlen(pos + 2) + 1); memcpy(pos, user, reflen); } else if ('g' == tolower(ref)) { /* %g found */ reflen = strlen(grp); exp = (char*) realloc(exp, strlen(exp) + reflen - 1); if(NULL == exp) { break; } pos = exp + offset; memmove(pos + reflen, pos + 2, strlen(pos + 2) + 1); memcpy(pos, grp, reflen); } else if (isdigit(ref)) { /* backreference (%1...%9) found */ if(NULL == match) { _pam_log(LOG_ERR, "%s: backreference \"%%%c\" found, but subject of match is NULL", opts->module, ref); _pam_drop(exp); return NULL; } refnum = ref - '0'; if(-1 != matchptr[refnum].rm_so) { /* submatch exists */ reflen = matchptr[refnum].rm_eo - matchptr[refnum].rm_so; exp = (char*) realloc(exp, strlen(exp) + reflen + 1); if(NULL == exp) { break; } pos = exp + offset; memmove(pos + reflen, pos + 2, strlen(pos + 2) + 1); memcpy (pos, match + matchptr[refnum].rm_so, reflen); } else { _pam_log(LOG_ERR, "%s: no submatch corresponding to backreference \"%%%c\"", opts->module, ref); _pam_drop(exp); return NULL; } } else if ('%' == ref) { /* %% found */ memmove(pos, pos + 1, strlen(pos) + 1); reflen = 1; } else { /* unknown ref */ _pam_log(LOG_ERR, "%s: unknown reference \"%%%c\"", opts->module, ref); _pam_drop(exp); return NULL; } offset += reflen; /* skip past what we just copied */ } if(NULL == exp) { /* catch realloc errors - don't forget to free old exp! */ _pam_log(LOG_ERR, "%s: realloc: %s", opts->module, strerror(errno)); free(pos - offset); return NULL; } if(opts->flags & _PAM_OPTS_DEBUG) { _pam_log(LOG_NOTICE, "%s: expanded path \"%s\" -> \"%s\"", opts->module, path, exp); } return exp; } /* parse the chroot.conf to find chroot_dir */ int _pam_get_chrootdir(const char* user, struct _pam_opts* opts) { FILE* conf; char conf_line[LINELEN]; int lineno, err, name_is_group, regflags = REG_ICASE, i; char *name, *mark, *group = NULL, **group_list = NULL; if(opts->flags & _PAM_OPTS_SECCHECKS) { /* don't need to distinguish the errors for now */ if(0 != _pam_check_path_perms(opts->conf, opts)) { return _PAM_CHROOT_SYSERR; } } if(!(conf = fopen(opts->conf, "r"))) { _pam_log(LOG_ERR, "%s: fopen(%s): %s", opts->module, opts->conf, strerror(errno)); opts->chroot_dir = NULL; return _PAM_CHROOT_SYSERR; } if(opts->flags & _PAM_OPTS_USE_GROUPS) { group_list = _pam_get_groups(user, opts); if(NULL == group_list) { /* probably some kind of malloc error */ fclose(conf); return _PAM_CHROOT_SYSERR; } else { group = group_list[0]; } } lineno = 0; err = 0; while(fgets(conf_line, LINELEN, conf)) { ++lineno; /* ignore comments and blank lines */ if((mark = strchr(conf_line, '#'))) { *mark = 0; } if(!(name = strtok(conf_line, " \t\r\n"))) { continue; } /* ignore lines that contain usernames/regexps but not directories */ if(!(mark = strtok(NULL, " \t\r\n"))) { _pam_log(LOG_ERR, "%s: %s %d: no directory", opts->module, opts->conf, lineno); continue; } /* is it a group? */ name_is_group = 0; if('@' == name[0]) { if(opts->flags & _PAM_OPTS_USE_GROUPS) { name_is_group = 1; name++; } else { _pam_log(LOG_ERR, "%s: %s %d: found @group style syntax, but use_groups has not been turned on", opts->module, opts->conf, lineno); fclose(conf); return _PAM_CHROOT_SYSERR; } } if(opts->flags & _PAM_OPTS_USE_REGEX) { regex_t name_regex; regmatch_t matchptr[10]; char const* match = NULL; if(opts->flags & _PAM_OPTS_USE_EXT_REGEX) { regflags |= REG_EXTENDED; } if(0 != (err = regcomp(&name_regex, name, regflags))) { size_t len = regerror(err, &name_regex, NULL, 0); char *errbuf = malloc(len); if(NULL == errbuf) { _pam_log(LOG_ERR, "%s: %s: malloc: %s", opts->module, __FUNCTION__, strerror(errno)); if(opts->flags & _PAM_OPTS_USE_GROUPS) { _pam_free_groups(group_list); } regfree(&name_regex); fclose(conf); return _PAM_CHROOT_SYSERR; } regerror(err, &name_regex, errbuf, len); _pam_log(LOG_ERR, "%s: %s %d: illegal regex \"%s\": %s", opts->module, opts->conf, lineno, name, errbuf); free(errbuf); regfree(&name_regex); continue; /* with the next line */ } if(1 == name_is_group) { for(i = 0; NULL != group_list[i]; i++) { match = group_list[i]; err = regexec(&name_regex, match, 10, matchptr, 0); if(0 == err) { break; } } } else { match = user; err = regexec(&name_regex, match, 10, matchptr, 0); } regfree(&name_regex); if(0 == err) { fclose(conf); opts->chroot_dir = _pam_expand_chroot_dir(mark, user, group, match, matchptr, opts); if(NULL == opts->chroot_dir) { _pam_log(LOG_ERR, "%s: unable to expand chroot_dir", opts->module); _pam_free_groups(group_list); return _PAM_CHROOT_SYSERR; } if (opts->flags & _PAM_OPTS_DEBUG) { _pam_log(LOG_NOTICE, "%s: found chroot_dir \"%s\" for user \"%s\"", opts->module, opts->chroot_dir, user); } _pam_free_groups(group_list); return _PAM_CHROOT_OK; } } else { char* tmp = name; /* tack a NULL at the end of the name field */ while(('\0' != *tmp) && !isspace(*tmp)) { tmp++; } *tmp = '\0'; if(1 == name_is_group) { for(i = 0; NULL != group_list[i]; i++) { if(0 == (err = strcmp(group_list[i], name))) { break; } } } else { err = strcmp(user, name); } if(0 == err) { fclose(conf); opts->chroot_dir = _pam_expand_chroot_dir(mark, user, group, NULL, NULL, opts); if(NULL == opts->chroot_dir) { _pam_log(LOG_ERR, "%s: unable to expand chroot_dir", opts->module); return _PAM_CHROOT_SYSERR; } if (opts->flags & _PAM_OPTS_DEBUG) { _pam_log(LOG_NOTICE, "%s: found chroot_dir \"%s\" for user \"%s\"", opts->module, opts->chroot_dir, user); } _pam_free_groups(group_list); return _PAM_CHROOT_OK; } } if(opts->flags & _PAM_OPTS_DEBUG) { _pam_log(LOG_NOTICE, "%s: \"%s\" does not match \"%s\"", opts->module, user, conf_line); } } /* end while(fgets(conf_line, LINELEN, conf)) */ if(opts->flags & _PAM_OPTS_DEBUG) { _pam_log(LOG_NOTICE, "%s: no match found for user \"%s\" in conf file \"%s\"", opts->module, user, opts->conf); } fclose(conf); _pam_free_groups(group_list); opts->chroot_dir = NULL; return _PAM_CHROOT_USERNOTFOUND; } /* This is the workhorse function. All of the pam_sm_* functions should * initialize a _pam_opts struct with the command line args and flags, * then pass it to this function */ int _pam_do_chroot(pam_handle_t *pamh, struct _pam_opts *opts) { int err,debug; char *name; char const *user; name = NULL; debug = opts->flags & _PAM_OPTS_DEBUG; err = pam_get_user(pamh, &user, NULL); if(PAM_CONV_AGAIN == err) { _pam_log(LOG_NOTICE, "$s: retry username lookup later", opts->module); return _PAM_CHROOT_INCOMPLETE; } else if(PAM_SUCCESS != err) { _pam_log(LOG_ERR, "%s: can't get username", opts->module); return _PAM_CHROOT_SYSERR; } if(opts->chroot_dir) { /* overrides the conf file */ if(debug) { _pam_log(LOG_NOTICE, "%s: chrootdir (%s) specified, ignoring conf file", opts->module, opts->chroot_dir); } err = _PAM_CHROOT_OK; } else { if(debug) { _pam_log(LOG_NOTICE, "%s: reading config file (%s)", opts->module, opts->conf); } err = _pam_get_chrootdir(user, opts); } if(_PAM_CHROOT_OK == err) { if(debug) { _pam_log(LOG_NOTICE, "%s: preparing to chroot()", opts->module); } if(NULL == opts->chroot_dir) { /* This is a state that I should never see. If the user wasn't in * the conf file, then USERNOTFOUND should have been returned. */ _pam_log(LOG_ERR, "%s: no chroot_dir set for \"%s\"", opts->module, user); return _PAM_CHROOT_INTERNALERR; } if(opts->flags & _PAM_OPTS_SECCHECKS) { if(0 != _pam_check_path_perms(opts->chroot_dir, opts)) { _pam_log(LOG_ERR, "%s: chroot_dir \"%s\" failed security check", opts->module, opts->chroot_dir); return _PAM_CHROOT_SYSERR; } } if(opts->flags & _PAM_OPTS_NO_CHROOT) { if(debug) { _pam_log(LOG_NOTICE, "%s: no_chroot is set, skipping chroot(%s)", opts->module, opts->chroot_dir); } } else if(chdir(opts->chroot_dir) != 0) { _pam_log(LOG_ERR, "%s: chdir(%s): %s", opts->module, opts->chroot_dir, strerror(errno)); return _PAM_CHROOT_SYSERR; } else if(chroot(opts->chroot_dir) != 0) { _pam_log(LOG_ERR, "%s: chroot(%s): %s", opts->module, opts->chroot_dir, strerror(errno)); return _PAM_CHROOT_SYSERR; } else { if(debug) { _pam_log(LOG_NOTICE, "%s: chroot(%s) ok", opts->module, opts->chroot_dir); } } return _PAM_CHROOT_OK; } else if(_PAM_CHROOT_USERNOTFOUND == err) { if(debug) { _pam_log(LOG_NOTICE, "%s: no match for %s in %s", opts->module, user, opts->conf); } return _PAM_CHROOT_USERNOTFOUND; } else { _pam_log(LOG_ERR, "%s: error determining chrootdir: user=\"%s\", dir=\"%s\"", opts->module, user, opts->chroot_dir); return err; } } PAM_EXTERN int pam_sm_authenticate(pam_handle_t *pamh, int flags, int argc, const char **argv) { int err; struct _pam_opts opts; _pam_opts_init(&opts); _pam_opts_config(&opts, flags, argc, argv); opts.module = "auth"; err = _pam_do_chroot(pamh, &opts); switch(err) { case _PAM_CHROOT_OK: if(opts.flags & _PAM_OPTS_DEBUG) { _pam_log(LOG_NOTICE, "%s: returning success", opts.module); } err = PAM_SUCCESS; break; case _PAM_CHROOT_USERNOTFOUND: if(opts.flags & _PAM_OPTS_DEBUG) { _pam_log(LOG_NOTICE, "%s: unknown user", opts.module); } err = PAM_USER_UNKNOWN; break; case _PAM_CHROOT_INCOMPLETE: _pam_log(LOG_NOTICE, "%s: returning incomplete", opts.module); err = PAM_INCOMPLETE; break; case _PAM_CHROOT_INTERNALERR: _pam_log(LOG_ERR, "%s: internal error encountered", opts.module); err = PAM_AUTH_ERR; break; default: if(opts.flags & _PAM_OPTS_DEBUG) { _pam_log(LOG_NOTICE, "%s: returning failure", opts.module); } err = PAM_AUTH_ERR; break; } _pam_opts_free(&opts); return err; } PAM_EXTERN int pam_sm_setcred(pam_handle_t *pamh, int flags, int argc, const char **argv) { _pam_log(LOG_ERR, "not a credentialator"); return PAM_IGNORE; } PAM_EXTERN int pam_sm_acct_mgmt(pam_handle_t *pamh, int flags, int argc, const char **argv) { int err; struct _pam_opts opts; _pam_opts_init(&opts); _pam_opts_config(&opts, flags, argc, argv); opts.module = "account"; err = _pam_do_chroot(pamh, &opts); switch(err) { case _PAM_CHROOT_OK: if(opts.flags & _PAM_OPTS_DEBUG) { _pam_log(LOG_NOTICE, "%s: returning success", opts.module); } err = PAM_SUCCESS; break; case _PAM_CHROOT_USERNOTFOUND: if(opts.flags & _PAM_OPTS_DEBUG) { _pam_log(LOG_NOTICE, "%s: unknown user", opts.module); } err = PAM_USER_UNKNOWN; break; case _PAM_CHROOT_INCOMPLETE: _pam_log(LOG_NOTICE, "%s: returning incomplete", opts.module); err = PAM_INCOMPLETE; break; case _PAM_CHROOT_INTERNALERR: _pam_log(LOG_ERR, "%s: internal error encountered", opts.module); err = PAM_AUTH_ERR; break; default: if(opts.flags & _PAM_OPTS_DEBUG) { _pam_log(LOG_NOTICE, "%s: returning failure", opts.module); } err = PAM_AUTH_ERR; break; } _pam_opts_free(&opts); return err; } PAM_EXTERN int pam_sm_open_session(pam_handle_t *pamh, int flags, int argc, const char **argv) { int err; struct _pam_opts opts; _pam_opts_init(&opts); _pam_opts_config(&opts, flags, argc, argv); opts.module = "session"; err = _pam_do_chroot(pamh, &opts); switch(err) { case _PAM_CHROOT_OK: if(opts.flags & _PAM_OPTS_DEBUG) { _pam_log(LOG_NOTICE, "%s: returning success", opts.module); } err = PAM_SUCCESS; break; case _PAM_CHROOT_USERNOTFOUND: if(opts.flags & _PAM_OPTS_NOTFOUNDFAILS) { if(opts.flags & _PAM_OPTS_DEBUG) { _pam_log(LOG_NOTICE, "%s: notfound=failure is set, returning failure", opts.module); } err = PAM_SESSION_ERR; } else { err = PAM_SUCCESS; } break; case _PAM_CHROOT_INCOMPLETE: _pam_log(LOG_NOTICE, "%s: returning incomplete", opts.module); err = PAM_INCOMPLETE; break; case _PAM_CHROOT_INTERNALERR: _pam_log(LOG_ERR, "%s: internal error encountered", opts.module); err = PAM_SESSION_ERR; break; default: if(opts.flags * _PAM_OPTS_DEBUG) { _pam_log(LOG_NOTICE, "%s: returning failure", opts.module); } err = PAM_SESSION_ERR; break; } _pam_opts_free(&opts); return err; } PAM_EXTERN int pam_sm_close_session(pam_handle_t *pamh, int flags, int argc, const char **argv) { return PAM_SUCCESS; } PAM_EXTERN int pam_sm_chauthtok(pam_handle_t *pamh, int flags, int argc, const char **argv) { _pam_log(LOG_ERR, "password management group is unsupported"); return PAM_SERVICE_ERR; }