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Diffstat (limited to 'modules/pam_limits/pam_limits.c')
| -rw-r--r-- | modules/pam_limits/pam_limits.c | 1144 |
1 files changed, 1144 insertions, 0 deletions
diff --git a/modules/pam_limits/pam_limits.c b/modules/pam_limits/pam_limits.c new file mode 100644 index 0000000..c1810e0 --- /dev/null +++ b/modules/pam_limits/pam_limits.c @@ -0,0 +1,1144 @@ +/* + * pam_limits - impose resource limits when opening a user session + * + * 1.6 - modified for PLD (added process priority settings) + * by Marcin Korzonek <mkorz@shadow.eu.org> + * 1.5 - Elliot Lee's "max system logins patch" + * 1.4 - addressed bug in configuration file parser + * 1.3 - modified the configuration file format + * 1.2 - added 'debug' and 'conf=' arguments + * 1.1 - added @group support + * 1.0 - initial release - Linux ONLY + * + * See end for Copyright information + */ + +#if !defined(linux) && !defined(__linux) +#warning THIS CODE IS KNOWN TO WORK ONLY ON LINUX !!! +#endif + +#include "config.h" + +#include <stdio.h> +#include <unistd.h> +#include <string.h> +#include <ctype.h> +#include <stdlib.h> +#include <errno.h> +#include <syslog.h> +#include <stdarg.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/resource.h> +#include <limits.h> +#include <glob.h> +#include <utmp.h> +#ifndef UT_USER /* some systems have ut_name instead of ut_user */ +#define UT_USER ut_user +#endif + +#include <grp.h> +#include <pwd.h> +#include <locale.h> + +#ifdef HAVE_LIBAUDIT +#include <libaudit.h> +#endif + +/* Module defines */ +#define LINE_LENGTH 1024 + +#define LIMITS_DEF_USER 0 /* limit was set by an user entry */ +#define LIMITS_DEF_GROUP 1 /* limit was set by a group entry */ +#define LIMITS_DEF_ALLGROUP 2 /* limit was set by a group entry */ +#define LIMITS_DEF_ALL 3 /* limit was set by an all entry */ +#define LIMITS_DEF_DEFAULT 4 /* limit was set by a default entry */ +#define LIMITS_DEF_KERNEL 5 /* limit was set from /proc/1/limits */ +#define LIMITS_DEF_NONE 6 /* this limit was not set yet */ + +#define LIMIT_RANGE_ERR -1 /* error in specified uid/gid range */ +#define LIMIT_RANGE_NONE 0 /* no range specified */ +#define LIMIT_RANGE_ONE 1 /* exact uid/gid specified (:max_uid)*/ +#define LIMIT_RANGE_MIN 2 /* only minimum uid/gid specified (min_uid:) */ +#define LIMIT_RANGE_MM 3 /* both min and max uid/gid specified (min_uid:max_uid) */ + +static const char *limits_def_names[] = { + "USER", + "GROUP", + "ALLGROUP", + "ALL", + "DEFAULT", + "KERNEL", + "NONE", + NULL +}; + +struct user_limits_struct { + int supported; + int src_soft; + int src_hard; + struct rlimit limit; +}; + +/* internal data */ +struct pam_limit_s { + int login_limit; /* the max logins limit */ + int login_limit_def; /* which entry set the login limit */ + int flag_numsyslogins; /* whether to limit logins only for a + specific user or to count all logins */ + int priority; /* the priority to run user process with */ + struct user_limits_struct limits[RLIM_NLIMITS]; + const char *conf_file; + int utmp_after_pam_call; + char login_group[LINE_LENGTH]; +}; + +#define LIMIT_LOGIN RLIM_NLIMITS+1 +#define LIMIT_NUMSYSLOGINS RLIM_NLIMITS+2 + +#define LIMIT_PRI RLIM_NLIMITS+3 + +#define LIMIT_SOFT 1 +#define LIMIT_HARD 2 + +#define PAM_SM_SESSION + +#include <security/pam_modules.h> +#include <security/_pam_macros.h> +#include <security/pam_modutil.h> +#include <security/pam_ext.h> + +/* argument parsing */ + +#define PAM_DEBUG_ARG 0x0001 +#define PAM_UTMP_EARLY 0x0004 +#define PAM_NO_AUDIT 0x0008 +#define PAM_SET_ALL 0x0010 + +/* Limits from globbed files. */ +#define LIMITS_CONF_GLOB LIMITS_FILE_DIR + +#define CONF_FILE (pl->conf_file != NULL)?pl->conf_file:LIMITS_FILE + +static int +_pam_parse (const pam_handle_t *pamh, int argc, const char **argv, + struct pam_limit_s *pl) +{ + int ctrl=0; + + /* step through arguments */ + for (ctrl=0; argc-- > 0; ++argv) { + + /* generic options */ + + if (!strcmp(*argv,"debug")) { + ctrl |= PAM_DEBUG_ARG; + } else if (!strncmp(*argv,"conf=",5)) { + pl->conf_file = *argv+5; + } else if (!strcmp(*argv,"utmp_early")) { + ctrl |= PAM_UTMP_EARLY; + } else if (!strcmp(*argv,"noaudit")) { + ctrl |= PAM_NO_AUDIT; + } else if (!strcmp(*argv,"set_all")) { + ctrl |= PAM_SET_ALL; + } else { + pam_syslog(pamh, LOG_ERR, "unknown option: %s", *argv); + } + } + + return ctrl; +} + +static const char * +rlimit2str (int i) +{ + switch (i) { + case RLIMIT_CPU: + return "cpu"; + break; + case RLIMIT_FSIZE: + return "fsize"; + break; + case RLIMIT_DATA: + return "data"; + break; + case RLIMIT_STACK: + return "stack"; + break; + case RLIMIT_CORE: + return "core"; + break; + case RLIMIT_RSS: + return "rss"; + break; + case RLIMIT_NPROC: + return "nproc"; + break; + case RLIMIT_NOFILE: + return "nofile"; + break; + case RLIMIT_MEMLOCK: + return "memlock"; + break; +#ifdef RLIMIT_AS + case RLIMIT_AS: + return "as"; + break; +#endif +#ifdef RLIMIT_LOCKS + case RLIMIT_LOCKS: + return "locks"; + break; +#endif +#ifdef RLIMIT_SIGPENDING + case RLIMIT_SIGPENDING: + return "sigpending"; + break; +#endif +#ifdef RLIMIT_MSGQUEUE + case RLIMIT_MSGQUEUE: + return "msgqueue"; + break; +#endif +#ifdef RLIMIT_NICE + case RLIMIT_NICE: + return "nice"; + break; +#endif +#ifdef RLIMIT_RTPRIO + case RLIMIT_RTPRIO: + return "rtprio"; + break; +#endif + default: + return "UNKNOWN"; + break; + } +} + + +#define LIMITED_OK 0 /* limit setting appeared to work */ +#define LIMIT_ERR 1 /* error setting a limit */ +#define LOGIN_ERR 2 /* too many logins err */ + +/* Counts the number of user logins and check against the limit*/ +static int +check_logins (pam_handle_t *pamh, const char *name, int limit, int ctrl, + struct pam_limit_s *pl) +{ + struct utmp *ut; + int count; + + if (ctrl & PAM_DEBUG_ARG) { + pam_syslog(pamh, LOG_DEBUG, + "checking logins for '%s' (maximum of %d)", name, limit); + } + + if (limit < 0) + return 0; /* no limits imposed */ + if (limit == 0) /* maximum 0 logins ? */ { + pam_syslog(pamh, LOG_WARNING, "No logins allowed for '%s'", name); + return LOGIN_ERR; + } + + setutent(); + + /* Because there is no definition about when an application + actually adds a utmp entry, some applications bizarrely do the + utmp call before the have PAM authenticate them to the system: + you're logged it, sort of...? Anyway, you can use the + "utmp_early" module argument in your PAM config file to make + allowances for this sort of problem. (There should be a PAM + standard for this, since if a module wants to actually map a + username then any early utmp entry will be for the unmapped + name = broken.) */ + + if (ctrl & PAM_UTMP_EARLY) { + count = 0; + } else { + count = 1; + } + + while((ut = getutent())) { +#ifdef USER_PROCESS + if (ut->ut_type != USER_PROCESS) { + continue; + } +#endif + if (ut->UT_USER[0] == '\0') { + continue; + } + if (!pl->flag_numsyslogins) { + if (((pl->login_limit_def == LIMITS_DEF_USER) + || (pl->login_limit_def == LIMITS_DEF_GROUP) + || (pl->login_limit_def == LIMITS_DEF_DEFAULT)) + && strncmp(name, ut->UT_USER, sizeof(ut->UT_USER)) != 0) { + continue; + } + if ((pl->login_limit_def == LIMITS_DEF_ALLGROUP) + && !pam_modutil_user_in_group_nam_nam(pamh, ut->UT_USER, pl->login_group)) { + continue; + } + } + if (++count > limit) { + break; + } + } + endutent(); + if (count > limit) { + if (name) { + pam_syslog(pamh, LOG_WARNING, + "Too many logins (max %d) for %s", limit, name); + } else { + pam_syslog(pamh, LOG_WARNING, "Too many system logins (max %d)", limit); + } + return LOGIN_ERR; + } + return 0; +} + +static const char *lnames[RLIM_NLIMITS] = { + [RLIMIT_CPU] = "Max cpu time", + [RLIMIT_FSIZE] = "Max file size", + [RLIMIT_DATA] = "Max data size", + [RLIMIT_STACK] = "Max stack size", + [RLIMIT_CORE] = "Max core file size", + [RLIMIT_RSS] = "Max resident set", + [RLIMIT_NPROC] = "Max processes", + [RLIMIT_NOFILE] = "Max open files", + [RLIMIT_MEMLOCK] = "Max locked memory", +#ifdef RLIMIT_AS + [RLIMIT_AS] = "Max address space", +#endif +#ifdef RLIMIT_LOCKS + [RLIMIT_LOCKS] = "Max file locks", +#endif +#ifdef RLIMIT_SIGPENDING + [RLIMIT_SIGPENDING] = "Max pending signals", +#endif +#ifdef RLIMIT_MSGQUEUE + [RLIMIT_MSGQUEUE] = "Max msgqueue size", +#endif +#ifdef RLIMIT_NICE + [RLIMIT_NICE] = "Max nice priority", +#endif +#ifdef RLIMIT_RTPRIO + [RLIMIT_RTPRIO] = "Max realtime priority", +#endif +#ifdef RLIMIT_RTTIME + [RLIMIT_RTTIME] = "Max realtime timeout", +#endif +}; + +static int str2rlimit(char *name) { + int i; + if (!name || *name == '\0') + return -1; + for(i = 0; i < RLIM_NLIMITS; i++) { + if (strcmp(name, lnames[i]) == 0) return i; + } + return -1; +} + +static rlim_t str2rlim_t(char *value) { + unsigned long long rlimit = 0; + + if (!value) return (rlim_t)rlimit; + if (strcmp(value, "unlimited") == 0) { + return RLIM_INFINITY; + } + rlimit = strtoull(value, NULL, 10); + return (rlim_t)rlimit; +} + +#define LIMITS_SKIP_WHITESPACE { \ + /* step backwards over spaces */ \ + pos--; \ + while (pos && line[pos] == ' ') pos--; \ + if (!pos) continue; \ + line[pos+1] = '\0'; \ +} +#define LIMITS_MARK_ITEM(item) { \ + /* step backwards over non-spaces */ \ + pos--; \ + while (pos && line[pos] != ' ') pos--; \ + if (!pos) continue; \ + item = line + pos + 1; \ +} + +static void parse_kernel_limits(pam_handle_t *pamh, struct pam_limit_s *pl, int ctrl) +{ + int i, maxlen = 0; + FILE *limitsfile; + const char *proclimits = "/proc/1/limits"; + char line[256]; + char *units, *hard, *soft, *name; + + if (!(limitsfile = fopen(proclimits, "r"))) { + pam_syslog(pamh, LOG_WARNING, "Could not read %s (%s), using PAM defaults", proclimits, strerror(errno)); + return; + } + + while (fgets(line, 256, limitsfile)) { + int pos = strlen(line); + if (pos < 2) continue; + + /* drop trailing newline */ + if (line[pos-1] == '\n') { + pos--; + line[pos] = '\0'; + } + + /* determine formatting boundry of limits report */ + if (!maxlen && strncmp(line, "Limit", 5) == 0) { + maxlen = pos; + continue; + } + + if (pos == maxlen) { + /* step backwards over "Units" name */ + LIMITS_SKIP_WHITESPACE; + LIMITS_MARK_ITEM(units); + } + else { + units = ""; + } + + /* step backwards over "Hard Limit" value */ + LIMITS_SKIP_WHITESPACE; + LIMITS_MARK_ITEM(hard); + + /* step backwards over "Soft Limit" value */ + LIMITS_SKIP_WHITESPACE; + LIMITS_MARK_ITEM(soft); + + /* step backwards over name of limit */ + LIMITS_SKIP_WHITESPACE; + name = line; + + i = str2rlimit(name); + if (i < 0 || i >= RLIM_NLIMITS) { + if (ctrl & PAM_DEBUG_ARG) + pam_syslog(pamh, LOG_DEBUG, "Unknown kernel rlimit '%s' ignored", name); + continue; + } + pl->limits[i].limit.rlim_cur = str2rlim_t(soft); + pl->limits[i].limit.rlim_max = str2rlim_t(hard); + pl->limits[i].src_soft = LIMITS_DEF_KERNEL; + pl->limits[i].src_hard = LIMITS_DEF_KERNEL; + } + fclose(limitsfile); +} + +static int init_limits(pam_handle_t *pamh, struct pam_limit_s *pl, int ctrl) +{ + int i; + int retval = PAM_SUCCESS; + + D(("called.")); + + for(i = 0; i < RLIM_NLIMITS; i++) { + int r = getrlimit(i, &pl->limits[i].limit); + if (r == -1) { + pl->limits[i].supported = 0; + if (errno != EINVAL) { + retval = !PAM_SUCCESS; + } + } else { + pl->limits[i].supported = 1; + pl->limits[i].src_soft = LIMITS_DEF_NONE; + pl->limits[i].src_hard = LIMITS_DEF_NONE; + } + } + +#ifdef __linux__ + if (ctrl & PAM_SET_ALL) { + parse_kernel_limits(pamh, pl, ctrl); + + for(i = 0; i < RLIM_NLIMITS; i++) { + if (pl->limits[i].supported && + (pl->limits[i].src_soft == LIMITS_DEF_NONE || + pl->limits[i].src_hard == LIMITS_DEF_NONE)) { + pam_syslog(pamh, LOG_WARNING, "Did not find kernel RLIMIT for %s, using PAM default", rlimit2str(i)); + } + } + } +#endif + + errno = 0; + pl->priority = getpriority (PRIO_PROCESS, 0); + if (pl->priority == -1 && errno != 0) + retval = !PAM_SUCCESS; + pl->login_limit = -2; + pl->login_limit_def = LIMITS_DEF_NONE; + + return retval; +} + +static void +process_limit (const pam_handle_t *pamh, int source, const char *lim_type, + const char *lim_item, const char *lim_value, + int ctrl, struct pam_limit_s *pl) +{ + int limit_item; + int limit_type = 0; + int int_value = 0; + rlim_t rlimit_value = 0; + char *endptr; + const char *value_orig = lim_value; + + if (ctrl & PAM_DEBUG_ARG) + pam_syslog(pamh, LOG_DEBUG, "%s: processing %s %s %s for %s", + __FUNCTION__, lim_type, lim_item, lim_value, + limits_def_names[source]); + + if (strcmp(lim_item, "cpu") == 0) + limit_item = RLIMIT_CPU; + else if (strcmp(lim_item, "fsize") == 0) + limit_item = RLIMIT_FSIZE; + else if (strcmp(lim_item, "data") == 0) + limit_item = RLIMIT_DATA; + else if (strcmp(lim_item, "stack") == 0) + limit_item = RLIMIT_STACK; + else if (strcmp(lim_item, "core") == 0) + limit_item = RLIMIT_CORE; + else if (strcmp(lim_item, "rss") == 0) + limit_item = RLIMIT_RSS; + else if (strcmp(lim_item, "nproc") == 0) + limit_item = RLIMIT_NPROC; + else if (strcmp(lim_item, "nofile") == 0) + limit_item = RLIMIT_NOFILE; + else if (strcmp(lim_item, "memlock") == 0) + limit_item = RLIMIT_MEMLOCK; +#ifdef RLIMIT_AS + else if (strcmp(lim_item, "as") == 0) + limit_item = RLIMIT_AS; +#endif /*RLIMIT_AS*/ +#ifdef RLIMIT_LOCKS + else if (strcmp(lim_item, "locks") == 0) + limit_item = RLIMIT_LOCKS; +#endif +#ifdef RLIMIT_SIGPENDING + else if (strcmp(lim_item, "sigpending") == 0) + limit_item = RLIMIT_SIGPENDING; +#endif +#ifdef RLIMIT_MSGQUEUE + else if (strcmp(lim_item, "msgqueue") == 0) + limit_item = RLIMIT_MSGQUEUE; +#endif +#ifdef RLIMIT_NICE + else if (strcmp(lim_item, "nice") == 0) + limit_item = RLIMIT_NICE; +#endif +#ifdef RLIMIT_RTPRIO + else if (strcmp(lim_item, "rtprio") == 0) + limit_item = RLIMIT_RTPRIO; +#endif + else if (strcmp(lim_item, "maxlogins") == 0) { + limit_item = LIMIT_LOGIN; + pl->flag_numsyslogins = 0; + } else if (strcmp(lim_item, "maxsyslogins") == 0) { + limit_item = LIMIT_NUMSYSLOGINS; + pl->flag_numsyslogins = 1; + } else if (strcmp(lim_item, "priority") == 0) { + limit_item = LIMIT_PRI; + } else { + pam_syslog(pamh, LOG_DEBUG, "unknown limit item '%s'", lim_item); + return; + } + + if (strcmp(lim_type,"soft")==0) + limit_type=LIMIT_SOFT; + else if (strcmp(lim_type, "hard")==0) + limit_type=LIMIT_HARD; + else if (strcmp(lim_type,"-")==0) + limit_type=LIMIT_SOFT | LIMIT_HARD; + else if (limit_item != LIMIT_LOGIN && limit_item != LIMIT_NUMSYSLOGINS) { + pam_syslog(pamh, LOG_DEBUG, "unknown limit type '%s'", lim_type); + return; + } + if (limit_item != LIMIT_PRI +#ifdef RLIMIT_NICE + && limit_item != RLIMIT_NICE +#endif + && (strcmp(lim_value, "-1") == 0 + || strcmp(lim_value, "-") == 0 || strcmp(lim_value, "unlimited") == 0 + || strcmp(lim_value, "infinity") == 0)) { + int_value = -1; + rlimit_value = RLIM_INFINITY; + } else if (limit_item == LIMIT_PRI || limit_item == LIMIT_LOGIN || +#ifdef RLIMIT_NICE + limit_item == RLIMIT_NICE || +#endif + limit_item == LIMIT_NUMSYSLOGINS) { + long temp; + temp = strtol (lim_value, &endptr, 10); + temp = temp < INT_MAX ? temp : INT_MAX; + int_value = temp > INT_MIN ? temp : INT_MIN; + if (int_value == 0 && value_orig == endptr) { + pam_syslog(pamh, LOG_DEBUG, + "wrong limit value '%s' for limit type '%s'", + lim_value, lim_type); + return; + } + } else { +#ifdef __USE_FILE_OFFSET64 + rlimit_value = strtoull (lim_value, &endptr, 10); +#else + rlimit_value = strtoul (lim_value, &endptr, 10); +#endif + if (rlimit_value == 0 && value_orig == endptr) { + pam_syslog(pamh, LOG_DEBUG, + "wrong limit value '%s' for limit type '%s'", + lim_value, lim_type); + return; + } + } + + /* one more special case when limiting logins */ + if ((source == LIMITS_DEF_ALL || source == LIMITS_DEF_ALLGROUP) + && (limit_item != LIMIT_LOGIN)) { + if (ctrl & PAM_DEBUG_ARG) + pam_syslog(pamh, LOG_DEBUG, + "'%%' domain valid for maxlogins type only"); + return; + } + + switch(limit_item) { + case RLIMIT_CPU: + if (rlimit_value != RLIM_INFINITY) + { + if (rlimit_value >= RLIM_INFINITY/60) + rlimit_value = RLIM_INFINITY; + else + rlimit_value *= 60; + } + break; + case RLIMIT_FSIZE: + case RLIMIT_DATA: + case RLIMIT_STACK: + case RLIMIT_CORE: + case RLIMIT_RSS: + case RLIMIT_MEMLOCK: +#ifdef RLIMIT_AS + case RLIMIT_AS: +#endif + if (rlimit_value != RLIM_INFINITY) + { + if (rlimit_value >= RLIM_INFINITY/1024) + rlimit_value = RLIM_INFINITY; + else + rlimit_value *= 1024; + } + break; +#ifdef RLIMIT_NICE + case RLIMIT_NICE: + if (int_value > 19) + int_value = 19; + if (int_value < -20) + int_value = -20; + rlimit_value = 20 - int_value; + break; +#endif + } + + if ( (limit_item != LIMIT_LOGIN) + && (limit_item != LIMIT_NUMSYSLOGINS) + && (limit_item != LIMIT_PRI) ) { + if (limit_type & LIMIT_SOFT) { + if (pl->limits[limit_item].src_soft < source) { + return; + } else { + pl->limits[limit_item].limit.rlim_cur = rlimit_value; + pl->limits[limit_item].src_soft = source; + } + } + if (limit_type & LIMIT_HARD) { + if (pl->limits[limit_item].src_hard < source) { + return; + } else { + pl->limits[limit_item].limit.rlim_max = rlimit_value; + pl->limits[limit_item].src_hard = source; + } + } + } else { + /* recent kernels support negative priority limits (=raise priority) */ + + if (limit_item == LIMIT_PRI) { + pl->priority = int_value; + } else { + if (pl->login_limit_def < source) { + return; + } else { + pl->login_limit = int_value; + pl->login_limit_def = source; + } + } + } + return; +} + +static int +parse_uid_range(pam_handle_t *pamh, const char *domain, + uid_t *min_uid, uid_t *max_uid) +{ + const char *range = domain; + char *pmax; + char *endptr; + int rv = LIMIT_RANGE_MM; + + if ((pmax=strchr(range, ':')) == NULL) + return LIMIT_RANGE_NONE; + ++pmax; + + if (range[0] == '@' || range[0] == '%') + ++range; + + if (range[0] == ':') + rv = LIMIT_RANGE_ONE; + else { + errno = 0; + *min_uid = strtoul (range, &endptr, 10); + if (errno != 0 || (range == endptr) || *endptr != ':') { + pam_syslog(pamh, LOG_DEBUG, + "wrong min_uid/gid value in '%s'", domain); + return LIMIT_RANGE_ERR; + } + } + + if (*pmax == '\0') { + if (rv == LIMIT_RANGE_ONE) + return LIMIT_RANGE_ERR; + else + return LIMIT_RANGE_MIN; + } + + errno = 0; + *max_uid = strtoul (pmax, &endptr, 10); + if (errno != 0 || (pmax == endptr) || *endptr != '\0') { + pam_syslog(pamh, LOG_DEBUG, + "wrong max_uid/gid value in '%s'", domain); + return LIMIT_RANGE_ERR; + } + + if (rv == LIMIT_RANGE_ONE) + *min_uid = *max_uid; + return rv; +} + +static int +parse_config_file(pam_handle_t *pamh, const char *uname, uid_t uid, gid_t gid, + int ctrl, struct pam_limit_s *pl) +{ + FILE *fil; + char buf[LINE_LENGTH]; + + /* check for the LIMITS_FILE */ + if (ctrl & PAM_DEBUG_ARG) + pam_syslog(pamh, LOG_DEBUG, "reading settings from '%s'", CONF_FILE); + fil = fopen(CONF_FILE, "r"); + if (fil == NULL) { + pam_syslog (pamh, LOG_WARNING, + "cannot read settings from %s: %m", CONF_FILE); + return PAM_SERVICE_ERR; + } + + /* start the show */ + while (fgets(buf, LINE_LENGTH, fil) != NULL) { + char domain[LINE_LENGTH]; + char ltype[LINE_LENGTH]; + char item[LINE_LENGTH]; + char value[LINE_LENGTH]; + int i; + int rngtype; + size_t j; + char *tptr,*line; + uid_t min_uid = (uid_t)-1, max_uid = (uid_t)-1; + + line = buf; + /* skip the leading white space */ + while (*line && isspace(*line)) + line++; + + /* Rip off the comments */ + tptr = strchr(line,'#'); + if (tptr) + *tptr = '\0'; + /* Rip off the newline char */ + tptr = strchr(line,'\n'); + if (tptr) + *tptr = '\0'; + /* Anything left ? */ + if (!strlen(line)) + continue; + + domain[0] = ltype[0] = item[0] = value[0] = '\0'; + + i = sscanf(line,"%s%s%s%s", domain, ltype, item, value); + D(("scanned line[%d]: domain[%s], ltype[%s], item[%s], value[%s]", + i, domain, ltype, item, value)); + + for(j=0; j < strlen(ltype); j++) + ltype[j]=tolower(ltype[j]); + + if ((rngtype=parse_uid_range(pamh, domain, &min_uid, &max_uid)) < 0) { + pam_syslog(pamh, LOG_WARNING, "invalid uid range '%s' - skipped", domain); + continue; + } + + if (i == 4) { /* a complete line */ + for(j=0; j < strlen(item); j++) + item[j]=tolower(item[j]); + for(j=0; j < strlen(value); j++) + value[j]=tolower(value[j]); + + if (strcmp(uname, domain) == 0) /* this user have a limit */ + process_limit(pamh, LIMITS_DEF_USER, ltype, item, value, ctrl, pl); + else if (domain[0]=='@') { + if (ctrl & PAM_DEBUG_ARG) { + pam_syslog(pamh, LOG_DEBUG, + "checking if %s is in group %s", + uname, domain + 1); + } + switch(rngtype) { + case LIMIT_RANGE_NONE: + if (pam_modutil_user_in_group_nam_nam(pamh, uname, domain+1)) + process_limit(pamh, LIMITS_DEF_GROUP, ltype, item, value, ctrl, + pl); + break; + case LIMIT_RANGE_ONE: + if (pam_modutil_user_in_group_nam_gid(pamh, uname, (gid_t)max_uid)) + process_limit(pamh, LIMITS_DEF_GROUP, ltype, item, value, ctrl, + pl); + break; + case LIMIT_RANGE_MM: + if (gid > (gid_t)max_uid) + break; + /* fallthrough */ + case LIMIT_RANGE_MIN: + if (gid >= (gid_t)min_uid) + process_limit(pamh, LIMITS_DEF_GROUP, ltype, item, value, ctrl, + pl); + } + } else if (domain[0]=='%') { + if (ctrl & PAM_DEBUG_ARG) { + pam_syslog(pamh, LOG_DEBUG, + "checking if %s is in group %s", + uname, domain + 1); + } + switch(rngtype) { + case LIMIT_RANGE_NONE: + if (strcmp(domain,"%") == 0) + process_limit(pamh, LIMITS_DEF_ALL, ltype, item, value, ctrl, + pl); + else if (pam_modutil_user_in_group_nam_nam(pamh, uname, domain+1)) { + strcpy(pl->login_group, domain+1); + process_limit(pamh, LIMITS_DEF_ALLGROUP, ltype, item, value, ctrl, + pl); + } + break; + case LIMIT_RANGE_ONE: + if (pam_modutil_user_in_group_nam_gid(pamh, uname, (gid_t)max_uid)) { + struct group *grp; + grp = pam_modutil_getgrgid(pamh, (gid_t)max_uid); + strncpy(pl->login_group, grp->gr_name, sizeof(pl->login_group)); + pl->login_group[sizeof(pl->login_group)-1] = '\0'; + process_limit(pamh, LIMITS_DEF_ALLGROUP, ltype, item, value, ctrl, + pl); + } + break; + case LIMIT_RANGE_MIN: + case LIMIT_RANGE_MM: + pam_syslog(pamh, LOG_WARNING, "range unsupported for %%group matching - ignored"); + } + } else { + switch(rngtype) { + case LIMIT_RANGE_NONE: + if (strcmp(domain, "*") == 0) + process_limit(pamh, LIMITS_DEF_DEFAULT, ltype, item, value, ctrl, + pl); + break; + case LIMIT_RANGE_ONE: + if (uid != max_uid) + break; + /* fallthrough */ + case LIMIT_RANGE_MM: + if (uid > max_uid) + break; + /* fallthrough */ + case LIMIT_RANGE_MIN: + if (uid >= min_uid) + process_limit(pamh, LIMITS_DEF_USER, ltype, item, value, ctrl, pl); + } + } + } else if (i == 2 && ltype[0] == '-') { /* Probably a no-limit line */ + if (strcmp(uname, domain) == 0) { + if (ctrl & PAM_DEBUG_ARG) { + pam_syslog(pamh, LOG_DEBUG, "no limits for '%s'", uname); + } + } else if (domain[0] == '@') { + switch(rngtype) { + case LIMIT_RANGE_NONE: + if (!pam_modutil_user_in_group_nam_nam(pamh, uname, domain+1)) + continue; /* next line */ + break; + case LIMIT_RANGE_ONE: + if (!pam_modutil_user_in_group_nam_gid(pamh, uname, (gid_t)max_uid)) + continue; /* next line */ + break; + case LIMIT_RANGE_MM: + if (gid > (gid_t)max_uid) + continue; /* next line */ + /* fallthrough */ + case LIMIT_RANGE_MIN: + if (gid < (gid_t)min_uid) + continue; /* next line */ + } + if (ctrl & PAM_DEBUG_ARG) { + pam_syslog(pamh, LOG_DEBUG, + "no limits for '%s' in group '%s'", + uname, domain+1); + } + } else { + switch(rngtype) { + case LIMIT_RANGE_NONE: + continue; /* next line */ + case LIMIT_RANGE_ONE: + if (uid != max_uid) + continue; /* next line */ + break; + case LIMIT_RANGE_MM: + if (uid > max_uid) + continue; /* next line */ + /* fallthrough */ + case LIMIT_RANGE_MIN: + if (uid >= min_uid) + break; + continue; /* next line */ + } + if (ctrl & PAM_DEBUG_ARG) { + pam_syslog(pamh, LOG_DEBUG, "no limits for '%s'", uname); + } + } + fclose(fil); + return PAM_IGNORE; + } else { + pam_syslog(pamh, LOG_WARNING, "invalid line '%s' - skipped", line); + } + } + fclose(fil); + return PAM_SUCCESS; +} + +static int setup_limits(pam_handle_t *pamh, + const char *uname, uid_t uid, int ctrl, + struct pam_limit_s *pl) +{ + int i; + int status; + int retval = LIMITED_OK; + + for (i=0, status=LIMITED_OK; i<RLIM_NLIMITS; i++) { + int res; + + if (!pl->limits[i].supported) { + /* skip it if its not known to the system */ + continue; + } + if (pl->limits[i].src_soft == LIMITS_DEF_NONE && + pl->limits[i].src_hard == LIMITS_DEF_NONE) { + /* skip it if its not initialized */ + continue; + } + if (pl->limits[i].limit.rlim_cur > pl->limits[i].limit.rlim_max) + pl->limits[i].limit.rlim_cur = pl->limits[i].limit.rlim_max; + res = setrlimit(i, &pl->limits[i].limit); + if (res != 0) + pam_syslog(pamh, LOG_ERR, "Could not set limit for '%s': %m", + rlimit2str(i)); + status |= res; + } + + if (status) { + retval = LIMIT_ERR; + } + + status = setpriority(PRIO_PROCESS, 0, pl->priority); + if (status != 0) { + pam_syslog(pamh, LOG_ERR, "Could not set limit for PRIO_PROCESS: %m"); + retval = LIMIT_ERR; + } + + if (uid == 0) { + D(("skip login limit check for uid=0")); + } else if (pl->login_limit > 0) { + if (check_logins(pamh, uname, pl->login_limit, ctrl, pl) == LOGIN_ERR) { +#ifdef HAVE_LIBAUDIT + if (!(ctrl & PAM_NO_AUDIT)) { + pam_modutil_audit_write(pamh, AUDIT_ANOM_LOGIN_SESSIONS, + "pam_limits", PAM_PERM_DENIED); + /* ignore return value as we fail anyway */ + } +#endif + retval |= LOGIN_ERR; + } + } else if (pl->login_limit == 0) { + retval |= LOGIN_ERR; + } + + return retval; +} + +/* now the session stuff */ +PAM_EXTERN int +pam_sm_open_session (pam_handle_t *pamh, int flags UNUSED, + int argc, const char **argv) +{ + int retval; + int i; + int glob_rc; + char *user_name; + struct passwd *pwd; + int ctrl; + struct pam_limit_s plstruct; + struct pam_limit_s *pl = &plstruct; + glob_t globbuf; + const char *oldlocale; + + D(("called.")); + + memset(pl, 0, sizeof(*pl)); + memset(&globbuf, 0, sizeof(globbuf)); + + ctrl = _pam_parse(pamh, argc, argv, pl); + retval = pam_get_item( pamh, PAM_USER, (void*) &user_name ); + if ( user_name == NULL || retval != PAM_SUCCESS ) { + pam_syslog(pamh, LOG_CRIT, "open_session - error recovering username"); + return PAM_SESSION_ERR; + } + + pwd = pam_modutil_getpwnam(pamh, user_name); + if (!pwd) { + if (ctrl & PAM_DEBUG_ARG) + pam_syslog(pamh, LOG_WARNING, + "open_session username '%s' does not exist", user_name); + return PAM_USER_UNKNOWN; + } + + retval = init_limits(pamh, pl, ctrl); + if (retval != PAM_SUCCESS) { + pam_syslog(pamh, LOG_WARNING, "cannot initialize"); + return PAM_ABORT; + } + + retval = parse_config_file(pamh, pwd->pw_name, pwd->pw_uid, pwd->pw_gid, ctrl, pl); + if (retval == PAM_IGNORE) { + D(("the configuration file ('%s') has an applicable '<domain> -' entry", CONF_FILE)); + return PAM_SUCCESS; + } + if (retval != PAM_SUCCESS || pl->conf_file != NULL) + /* skip reading limits.d if config file explicitely specified */ + goto out; + + /* Read subsequent *.conf files, if they exist. */ + + /* set the LC_COLLATE so the sorting order doesn't depend + on system locale */ + + oldlocale = setlocale(LC_COLLATE, "C"); + glob_rc = glob(LIMITS_CONF_GLOB, GLOB_ERR, NULL, &globbuf); + + if (oldlocale != NULL) + setlocale (LC_COLLATE, oldlocale); + + if (!glob_rc) { + /* Parse the *.conf files. */ + for (i = 0; globbuf.gl_pathv[i] != NULL; i++) { + pl->conf_file = globbuf.gl_pathv[i]; + retval = parse_config_file(pamh, pwd->pw_name, pwd->pw_uid, pwd->pw_gid, ctrl, pl); + if (retval == PAM_IGNORE) { + D(("the configuration file ('%s') has an applicable '<domain> -' entry", pl->conf_file)); + globfree(&globbuf); + return PAM_SUCCESS; + } + if (retval != PAM_SUCCESS) + goto out; + } + } + +out: + globfree(&globbuf); + if (retval != PAM_SUCCESS) + { + pam_syslog(pamh, LOG_WARNING, "error parsing the configuration file: '%s' ",CONF_FILE); + return retval; + } + + retval = setup_limits(pamh, pwd->pw_name, pwd->pw_uid, ctrl, pl); + if (retval & LOGIN_ERR) + pam_error(pamh, _("Too many logins for '%s'."), pwd->pw_name); + if (retval != LIMITED_OK) { + return PAM_PERM_DENIED; + } + + return PAM_SUCCESS; +} + +PAM_EXTERN int +pam_sm_close_session (pam_handle_t *pamh UNUSED, int flags UNUSED, + int argc UNUSED, const char **argv UNUSED) +{ + /* nothing to do */ + return PAM_SUCCESS; +} + +#ifdef PAM_STATIC + +/* static module data */ + +struct pam_module _pam_limits_modstruct = { + "pam_limits", + NULL, + NULL, + NULL, + pam_sm_open_session, + pam_sm_close_session, + NULL +}; +#endif + +/* + * Copyright (c) Cristian Gafton, 1996-1997, <gafton@redhat.com> + * 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, and the entire permission notice in its entirety, + * including the disclaimer of warranties. + * 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. The name of the author may not be used to endorse or promote + * products derived from this software without specific prior + * written permission. + * + * ALTERNATIVELY, this product may be distributed under the terms of + * the GNU Public License, in which case the provisions of the GPL are + * required INSTEAD OF the above restrictions. (This clause is + * necessary due to a potential bad interaction between the GPL and + * the restrictions contained in a BSD-style copyright.) + * + * THIS SOFTWARE IS PROVIDED ``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 AUTHOR 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. + */ |