/mandos/trunk : revision 282

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/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */

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/* -*- coding: utf-8 -*- */

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/*

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* Mandos plugin runner - Run Mandos plugins

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*

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#include <sys/select.h> /* fd_set, select(), FD_ZERO(),

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FD_SET(), FD_ISSET(), FD_CLR */

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#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),

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WEXITSTATUS(), WTERMSIG(),

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WCOREDUMP() */

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WEXITSTATUS() */

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#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */

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#include <iso646.h> /* and, or, not */

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#include <dirent.h> /* DIR, struct dirent, opendir(),

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close() */

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#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,

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FD_CLOEXEC */

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#include <string.h> /* strsep, strlen(), asprintf(),

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strsignal() */

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#include <string.h> /* strsep, strlen(), asprintf() */

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#include <errno.h> /* errno */

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#include <argp.h> /* struct argp_option, struct

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argp_state, struct argp,

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#include <signal.h> /* struct sigaction, sigemptyset(),

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sigaddset(), sigaction(),

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sigprocmask(), SIG_BLOCK, SIGCHLD,

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SIG_UNBLOCK, kill(), sig_atomic_t

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*/

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SIG_UNBLOCK, kill() */

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#include <errno.h> /* errno, EBADF */

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#include <inttypes.h> /* intmax_t, PRIdMAX, strtoimax() */

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#include <inttypes.h> /* intmax_t, SCNdMAX, PRIdMAX, */

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#define BUFFER_SIZE 256

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char **environ;

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int envc;

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bool disabled;

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/* Variables used for running processes*/

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pid_t pid;

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int fd;

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size_t buffer_size;

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size_t buffer_length;

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bool eof;

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volatile sig_atomic_t completed;

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int status;

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volatile bool completed;

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volatile int status;

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struct plugin *next;

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} plugin;

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}

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}

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*new_plugin = (plugin){ .name = copy_name,

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.argc = 1,

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.disabled = false,

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.next = plugin_list };

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*new_plugin = (plugin) { .name = copy_name,

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.argc = 1,

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.disabled = false,

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.next = plugin_list };

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new_plugin->argv = malloc(sizeof(char *) * 2);

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if(new_plugin->argv == NULL){

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/*

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* Based on the example in the GNU LibC manual chapter 13.13 "File

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* Descriptor Flags".

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| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |

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* *Note File Descriptor Flags:(libc)Descriptor Flags.

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*/

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static int set_cloexec_flag(int fd){

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int ret = fcntl(fd, F_GETFD, 0);

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/* Mark processes as completed when they exit, and save their exit

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status. */

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static void handle_sigchld(__attribute__((unused)) int sig){

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int old_errno = errno;

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while(true){

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plugin *proc = plugin_list;

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int status;

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break;

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}

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if(pid == -1){

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if(errno == ECHILD){

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/* No child processes */

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break;

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if(errno != ECHILD){

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perror("waitpid");

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}

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perror("waitpid");

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/* No child processes */

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break;

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}

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/* A child exited, find it in process_list */

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continue;

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}

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proc->status = status;

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proc->completed = 1;

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proc->completed = true;

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}

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errno = old_errno;

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}

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/* Prints out a password to stdout */

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}

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free(plugin_node->environ);

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free(plugin_node->buffer);

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/* Removes the plugin from the singly-linked list */

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if(plugin_node == plugin_list){

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/* First one - simple */

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struct dirent *dirst;

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struct stat st;

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fd_set rfds_all;

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int ret, maxfd = 0;

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int ret, numchars, maxfd = 0;

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ssize_t sret;

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intmax_t tmpmax;

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uid_t uid = 65534;

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};

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error_t parse_opt(int key, char *arg, __attribute__((unused))

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struct argp_state *state){

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char *tmp;

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switch(key){

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struct argp_state *state) {

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switch(key) {

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case 'g': /* --global-options */

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if(arg != NULL){

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char *plugin_option;

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while((plugin_option = strsep(&arg, ",")) != NULL){

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if(plugin_option[0] == '\0'){

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char *p;

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while((p = strsep(&arg, ",")) != NULL){

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if(p[0] == '\0'){

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continue;

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}

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if(not add_argument(getplugin(NULL), plugin_option)){

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if(not add_argument(getplugin(NULL), p)){

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perror("add_argument");

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return ARGP_ERR_UNKNOWN;

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}

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break;

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case 'o': /* --options-for */

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if(arg != NULL){

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char *plugin_name = strsep(&arg, ":");

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if(plugin_name[0] == '\0'){

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break;

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}

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char *plugin_option;

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while((plugin_option = strsep(&arg, ",")) != NULL){

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if(not add_argument(getplugin(plugin_name), plugin_option)){

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char *p_name = strsep(&arg, ":");

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if(p_name[0] == '\0' or arg == NULL){

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break;

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}

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char *opt = strsep(&arg, ":");

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if(opt[0] == '\0' or opt == NULL){

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break;

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}

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char *p;

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while((p = strsep(&opt, ",")) != NULL){

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if(p[0] == '\0'){

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continue;

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}

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if(not add_argument(getplugin(p_name), p)){

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perror("add_argument");

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return ARGP_ERR_UNKNOWN;

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}

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plugindir = strdup(arg);

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if(plugindir == NULL){

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perror("strdup");

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}

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}

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break;

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case 129: /* --config-file */

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/* This is already done by parse_opt_config_file() */

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break;

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case 130: /* --userid */

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errno = 0;

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tmpmax = strtoimax(arg, &tmp, 10);

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if(errno != 0 or tmp == arg or *tmp != '\0'

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or tmpmax != (uid_t)tmpmax){

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ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);

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if(ret < 1 or tmpmax != (uid_t)tmpmax

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or arg[numchars] != '\0'){

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fprintf(stderr, "Bad user ID number: \"%s\", using %"

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PRIdMAX "\n", arg, (intmax_t)uid);

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} else {

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}

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break;

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case 131: /* --groupid */

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errno = 0;

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tmpmax = strtoimax(arg, &tmp, 10);

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if(errno != 0 or tmp == arg or *tmp != '\0'

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or tmpmax != (gid_t)tmpmax){

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ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);

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if(ret < 1 or tmpmax != (gid_t)tmpmax

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or arg[numchars] != '\0'){

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fprintf(stderr, "Bad group ID number: \"%s\", using %"

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PRIdMAX "\n", arg, (intmax_t)gid);

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} else {

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ignores everything but the --config-file option. */

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error_t parse_opt_config_file(int key, char *arg,

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__attribute__((unused))

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struct argp_state *state){

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switch(key){

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struct argp_state *state) {

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switch(key) {

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case 'g': /* --global-options */

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case 'G': /* --global-env */

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case 'o': /* --options-for */

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if(argfile == NULL){

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perror("strdup");

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}

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break;

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break;

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case 130: /* --userid */

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case 131: /* --groupid */

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case 132: /* --debug */

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conffp = fopen(AFILE, "r");

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} else {

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conffp = fopen(argfile, "r");

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}

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}

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if(conffp != NULL){

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char *org_line = NULL;

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char *p, *arg, *new_arg, *line;

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size_t size = 0;

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const char whitespace_delims[] = " \r\t\f\v\n";

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const char comment_delim[] = "#";

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custom_argc = 1;

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custom_argv = malloc(sizeof(char*) * 2);

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if(custom_argv == NULL){

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}

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custom_argv[0] = argv[0];

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custom_argv[1] = NULL;

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/* for each line in the config file, strip whitespace and ignore

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commented text */

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while(true){

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if(sret == -1){

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break;

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}

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line = org_line;

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arg = strsep(&line, comment_delim);

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while((p = strsep(&arg, whitespace_delims)) != NULL){

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goto fallback;

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}

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custom_argv[custom_argc-1] = new_arg;

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custom_argv[custom_argc] = NULL;

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custom_argv[custom_argc] = NULL;

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}

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}

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do{

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ret = fclose(conffp);

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}while(ret == EOF and errno == EINTR);

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if(ret == EOF){

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perror("fclose");

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exitstatus = EXIT_FAILURE;

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goto fallback;

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}

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free(org_line);

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} else {

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/* Check for harmful errors and go to fallback. Other errors might

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}

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/* Strip permissions down to nobody */

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ret = setuid(uid);

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if(ret == -1){

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perror("setuid");

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}

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setgid(gid);

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if(ret == -1){

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perror("setgid");

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}

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ret = setuid(uid);

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if(ret == -1){

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perror("setuid");

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}

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if(plugindir == NULL){

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dir = opendir(PDIR);

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continue;

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}

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}

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char *filename;

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if(plugindir == NULL){

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ret = asprintf(&filename, PDIR "/%s", dirst->d_name);

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free(filename);

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continue;

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}

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/* Ignore non-executable files */

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if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){

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if(debug){

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closedir(dir);

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dir = NULL;

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free_plugin(getplugin(NULL));

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for(plugin *p = plugin_list; p != NULL; p = p->next){

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if(p->pid != 0){

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from one of them */

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for(plugin *proc = plugin_list; proc != NULL;){

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/* Is this process completely done? */

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if(proc->completed and proc->eof){

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if(proc->eof and proc->completed){

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/* Only accept the plugin output if it exited cleanly */

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if(not WIFEXITED(proc->status)

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or WEXITSTATUS(proc->status) != 0){

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/* Bad exit by plugin */

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if(debug){

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if(WIFEXITED(proc->status)){

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fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"

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" status %d\n", proc->name,

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(intmax_t) (proc->pid),

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fprintf(stderr, "Plugin %" PRIdMAX " exited with status"

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" %d\n", (intmax_t) (proc->pid),

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WEXITSTATUS(proc->status));

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} else if(WIFSIGNALED(proc->status)){

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fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"

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" signal %d: %s\n", proc->name,

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(intmax_t) (proc->pid),

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WTERMSIG(proc->status),

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strsignal(WTERMSIG(proc->status)));

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} else if(WIFSIGNALED(proc->status)) {

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fprintf(stderr, "Plugin %" PRIdMAX " killed by signal"

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" %d\n", (intmax_t) (proc->pid),

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WTERMSIG(proc->status));

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} else if(WCOREDUMP(proc->status)){

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fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"

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" core\n", proc->name, (intmax_t) (proc->pid));

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fprintf(stderr, "Plugin %" PRIdMAX " dumped core\n",

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(intmax_t) (proc->pid));

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}

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}

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/* Remove the plugin */

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FD_CLR(proc->fd, &rfds_all);

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/* Block signal while modifying process_list */

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ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);

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if(ret < 0){

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}

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}

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}

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fallback:

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if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){