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/* -*- coding: utf-8 -*- */
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/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
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* Mandos plugin runner - Run Mandos plugins
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* Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
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* This program is free software: you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation, either version 3 of the
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* License, or (at your option) any later version.
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* This program is distributed in the hope that it will be useful, but
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* Copyright © 2008-2022 Teddy Hogeborn
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* Copyright © 2008-2022 Björn Påhlsson
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* This file is part of Mandos.
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* Mandos is free software: you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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* Mandos is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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17
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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18
* General Public License for more details.
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20
* You should have received a copy of the GNU General Public License
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* along with this program. If not, see
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* <http://www.gnu.org/licenses/>.
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* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
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* Contact the authors at <mandos@fukt.bsnet.se>.
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* Contact the authors at <mandos@recompile.se>.
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#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */
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#define _GNU_SOURCE /* strchrnul(), TEMP_FAILURE_RETRY(),
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getline(), asprintf(), O_CLOEXEC,
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scandirat(), pipe2() */
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#include <argp.h> /* argp_program_version,
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argp_program_bug_address,
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struct argp_state, argp_error(),
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ARGP_NO_EXIT, argp_state_help,
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ARGP_HELP_USAGE, ARGP_HELP_EXIT_OK,
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ARGP_KEY_ARG, ARGP_ERR_UNKNOWN,
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struct argp, argp_parse(),
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ARGP_IN_ORDER, ARGP_NO_HELP */
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#include <stdbool.h> /* bool, false, true */
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#include <sys/types.h> /* pid_t, sig_atomic_t, uid_t, gid_t,
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getuid(), setgid(), setuid() */
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#include <stddef.h> /* size_t, NULL */
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#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
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EXIT_SUCCESS, realloc() */
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#include <stdbool.h> /* bool, true, false */
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#include <stdio.h> /* perror, popen(), fileno(),
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fprintf(), stderr, STDOUT_FILENO */
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#include <sys/types.h> /* DIR, opendir(), stat(), struct
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stat, waitpid(), WIFEXITED(),
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WEXITSTATUS(), wait(), pid_t,
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uid_t, gid_t, getuid(), getgid(),
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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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#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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readdir(), closedir(), dirfd() */
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#include <unistd.h> /* struct stat, stat(), S_ISREG(),
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fcntl(), setuid(), setgid(),
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F_GETFD, F_SETFD, FD_CLOEXEC,
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access(), pipe(), fork(), close()
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dup2, STDOUT_FILENO, _exit(),
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execv(), write(), read(),
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#include <iso646.h> /* or, and, not */
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#include <string.h> /* strcmp(), strdup(), strchrnul(),
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strncmp(), strlen(), strcpy(),
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strsep(), strchr(), strsignal() */
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#include <stdlib.h> /* malloc(), free(), reallocarray(),
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realloc(), EXIT_SUCCESS */
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#include <errno.h> /* errno, EINTR, ENOMEM, ECHILD,
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error_t, EINVAL, EMFILE, ENFILE,
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#include <stdint.h> /* SIZE_MAX */
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#define _GNU_SOURCE /* strchrnul(), TEMP_FAILURE_RETRY(),
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getline(), asprintf(), O_CLOEXEC,
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scandirat(), pipe2() */
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#include <unistd.h> /* TEMP_FAILURE_RETRY(), ssize_t,
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write(), STDOUT_FILENO, uid_t,
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gid_t, getuid(), fchown(), close(),
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symlink(), setgid(), setuid(),
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faccessat(), X_OK, pipe(), pipe2(),
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fork(), _exit(), dup2(), fexecve(),
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#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
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#include <string.h> /* strtok, strlen(), strcpy(),
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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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argp_parse(), ARGP_ERR_UNKNOWN,
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ARGP_KEY_END, ARGP_KEY_ARG, error_t */
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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() */
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#include <errno.h> /* errno, EBADF */
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FD_CLOEXEC, open(), O_RDONLY,
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O_CLOEXEC, openat() */
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#include <sys/wait.h> /* waitpid(), WNOHANG, WIFEXITED(),
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WEXITSTATUS(), WIFSIGNALED(),
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#include <error.h> /* error() */
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#include <stdio.h> /* FILE, fprintf(), fopen(),
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getline(), fclose(), EOF,
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#include <dirent.h> /* struct dirent, scandirat(),
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#include <sys/stat.h> /* struct stat, fstat(), S_ISDIR(),
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#include <sys/select.h> /* fd_set, FD_ZERO(), FD_SETSIZE,
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FD_SET(), select(), FD_CLR(),
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#include <signal.h> /* struct sigaction, SA_NOCLDSTOP,
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sigemptyset(), sigaddset(),
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SIGCHLD, sigprocmask(), SIG_BLOCK,
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SIG_UNBLOCK, kill(), SIGTERM */
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#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_IOERR,
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EX_CONFIG, EX_UNAVAILABLE, EX_OK */
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#include <inttypes.h> /* intmax_t, strtoimax(), PRIdMAX */
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#include <fnmatch.h> /* fnmatch(), FNM_FILE_NAME,
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FNM_PERIOD, FNM_NOMATCH */
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#define BUFFER_SIZE 256
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const char *argp_program_version = "mandos-client 1.0";
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const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
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typedef struct process{
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#define PDIR "/lib/mandos/plugins.d"
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#define PHDIR "/lib/mandos/plugin-helpers"
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#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
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const char *argp_program_version = "plugin-runner " VERSION;
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const char *argp_program_bug_address = "<mandos@recompile.se>";
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typedef struct plugin{
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char *name; /* can be NULL or any plugin name */
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/* Variables used for running processes*/
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size_t buffer_size;
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size_t buffer_length;
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volatile sig_atomic_t completed;
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typedef struct plugin{
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char *name; /* can be NULL or any plugin name */
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struct plugin *next;
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static plugin *getplugin(char *name, plugin **plugin_list){
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for (plugin *p = *plugin_list; p != NULL; p = p->next){
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or (p->name and name and (strcmp(p->name, name) == 0))){
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static plugin *plugin_list = NULL;
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/* Gets an existing plugin based on name,
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or if none is found, creates a new one */
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__attribute__((warn_unused_result))
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static plugin *getplugin(char *name){
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/* Check for existing plugin with that name */
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for(plugin *p = plugin_list; p != NULL; p = p->next){
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or (p->name and name and (strcmp(p->name, name) == 0))){
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/* Create a new plugin */
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plugin *new_plugin = malloc(sizeof(plugin));
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if (new_plugin == NULL){
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new_plugin->name = name;
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new_plugin->argv = malloc(sizeof(char *) * 2);
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if (new_plugin->argv == NULL){
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new_plugin->argv[0] = name;
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plugin *new_plugin = NULL;
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new_plugin = malloc(sizeof(plugin));
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} while(new_plugin == NULL and errno == EINTR);
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if(new_plugin == NULL){
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char *copy_name = NULL;
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copy_name = strdup(name);
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} while(copy_name == NULL and errno == EINTR);
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if(copy_name == NULL){
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*new_plugin = (plugin){ .name = copy_name,
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.next = plugin_list };
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new_plugin->argv = malloc(sizeof(char *) * 2);
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} while(new_plugin->argv == NULL and errno == EINTR);
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if(new_plugin->argv == NULL){
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new_plugin->argv[0] = copy_name;
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new_plugin->argv[1] = NULL;
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new_plugin->argc = 1;
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new_plugin->disabled = false;
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new_plugin->next = *plugin_list;
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new_plugin->environ = malloc(sizeof(char *));
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} while(new_plugin->environ == NULL and errno == EINTR);
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if(new_plugin->environ == NULL){
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free(new_plugin->argv);
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new_plugin->environ[0] = NULL;
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/* Append the new plugin to the list */
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*plugin_list = new_plugin;
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plugin_list = new_plugin;
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return new_plugin;
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static void addargument(plugin *p, char *arg){
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p->argv[p->argc] = arg;
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p->argv = realloc(p->argv, sizeof(char *) * (size_t)(p->argc + 2));
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if (p->argv == NULL){
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p->argv[p->argc] = NULL;
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/* Helper function for add_argument and add_environment */
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__attribute__((nonnull, warn_unused_result))
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static bool add_to_char_array(const char *new, char ***array,
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/* Resize the pointed-to array to hold one more pointer */
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char **new_array = NULL;
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#if defined(__GLIBC_PREREQ) and __GLIBC_PREREQ(2, 26)
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new_array = reallocarray(*array, (size_t)((*len) + 2),
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if(((size_t)((*len) + 2)) > (SIZE_MAX / sizeof(char *))){
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new_array = realloc(*array, (size_t)((*len) + 2)
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} while(new_array == NULL and errno == EINTR);
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if(new_array == NULL){
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/* Make a copy of the new string */
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} while(copy == NULL and errno == EINTR);
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/* Insert the copy */
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(*array)[*len] = copy;
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/* Add a new terminating NULL pointer to the last element */
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(*array)[*len] = NULL;
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/* Add to a plugin's argument vector */
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__attribute__((nonnull(2), warn_unused_result))
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static bool add_argument(plugin *p, const char *arg){
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return add_to_char_array(arg, &(p->argv), &(p->argc));
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/* Add to a plugin's environment */
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__attribute__((nonnull(2), warn_unused_result))
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static bool add_environment(plugin *p, const char *def, bool replace){
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/* namelen = length of name of environment variable */
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size_t namelen = (size_t)(strchrnul(def, '=') - def);
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/* Search for this environment variable */
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for(char **envdef = p->environ; *envdef != NULL; envdef++){
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if(strncmp(*envdef, def, namelen + 1) == 0){
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/* It already exists */
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new_envdef = realloc(*envdef, strlen(def) + 1);
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} while(new_envdef == NULL and errno == EINTR);
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if(new_envdef == NULL){
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*envdef = new_envdef;
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strcpy(*envdef, def);
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return add_to_char_array(def, &(p->environ), &(p->envc));
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271
* Based on the example in the GNU LibC manual chapter 13.13 "File
136
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* Descriptor Flags".
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* *Note File Descriptor Flags:(libc)Descriptor Flags.
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| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
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static int set_cloexec_flag(int fd)
141
int ret = fcntl(fd, F_GETFD, 0);
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__attribute__((warn_unused_result))
276
static int set_cloexec_flag(int fd){
277
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
142
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/* If reading the flags failed, return error indication now. */
146
282
/* Store modified flag word in the descriptor. */
147
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
283
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
150
process *process_list = NULL;
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/* Mark a process as completed when it exits, and save its exit
286
#endif /* not O_CLOEXEC */
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/* Mark processes as completed when they exit, and save their exit
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void handle_sigchld(__attribute__((unused)) int sig){
155
process *proc = process_list;
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pid_t pid = wait(&status);
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while(proc != NULL and proc->pid != pid){
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/* Process not found in process list */
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proc->status = status;
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proc->completed = true;
291
static void handle_sigchld(__attribute__((unused)) int sig){
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int old_errno = errno;
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plugin *proc = plugin_list;
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pid_t pid = waitpid(-1, &status, WNOHANG);
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/* Only still running child processes */
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/* No child processes */
306
error(0, errno, "waitpid");
309
/* A child exited, find it in process_list */
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while(proc != NULL and proc->pid != pid){
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/* Process not found in process list */
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proc->status = status;
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bool print_out_password(const char *buffer, size_t length){
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/* Prints out a password to stdout */
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__attribute__((nonnull, warn_unused_result))
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static bool print_out_password(const char *buffer, size_t length){
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if(length>0 and buffer[length-1] == '\n'){
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for(size_t written = 0; written < length; written += (size_t)ret){
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ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
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329
length - written));
223
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{ .name = "global-options", .key = 'g',
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.arg = "OPTION[,OPTION[,...]]",
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.doc = "Options passed to all plugins" },
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{ .name = "global-env", .key = 'G',
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.doc = "Environment variable passed to all plugins" },
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{ .name = "options-for", .key = 'o',
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.arg = "PLUGIN:OPTION[,OPTION[,...]]",
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.doc = "Options passed only to specified plugin" },
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{ .name = "env-for", .key = 'E',
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.arg = "PLUGIN:ENV=value",
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.doc = "Environment variable passed to specified plugin" },
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{ .name = "disable", .key = 'd',
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.doc = "Disable a specific plugin", .group = 1 },
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{ .name = "enable", .key = 'e',
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.doc = "Enable a specific plugin", .group = 1 },
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{ .name = "plugin-dir", .key = 128,
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.arg = "DIRECTORY",
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.doc = "Specify a different plugin directory", .group = 2 },
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{ .name = "userid", .key = 129,
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.arg = "ID", .flags = 0,
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.doc = "User ID the plugins will run as", .group = 2 },
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{ .name = "groupid", .key = 130,
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.arg = "ID", .flags = 0,
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.doc = "Group ID the plugins will run as", .group = 2 },
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{ .name = "debug", .key = 131,
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.doc = "Debug mode", .group = 3 },
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{ .name = "config-file", .key = 129,
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.doc = "Specify a different configuration file", .group = 2 },
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{ .name = "userid", .key = 130,
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.arg = "ID", .flags = 0,
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.doc = "User ID the plugins will run as", .group = 3 },
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{ .name = "groupid", .key = 131,
441
.arg = "ID", .flags = 0,
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.doc = "Group ID the plugins will run as", .group = 3 },
443
{ .name = "debug", .key = 132,
444
.doc = "Debug mode", .group = 4 },
445
{ .name = "plugin-helper-dir", .key = 133,
447
.doc = "Specify a different plugin helper directory",
450
* These reproduce what we would get without ARGP_NO_HELP
452
{ .name = "help", .key = '?',
453
.doc = "Give this help list", .group = -1 },
454
{ .name = "usage", .key = -3,
455
.doc = "Give a short usage message", .group = -1 },
456
{ .name = "version", .key = 'V',
457
.doc = "Print program version", .group = -1 },
246
error_t parse_opt (int key, char *arg, struct argp_state *state) {
247
/* Get the INPUT argument from `argp_parse', which we know is a
248
pointer to our plugin list pointer. */
249
plugin **plugins = state->input;
253
char *p = strtok(arg, ",");
255
addargument(getplugin(NULL, plugins), p);
256
p = strtok(NULL, ",");
262
char *name = strtok(arg, ":");
263
char *p = strtok(NULL, ":");
267
addargument(getplugin(name, plugins), p);
268
p = strtok(NULL, ",");
275
getplugin(arg, plugins)->disabled = true;
282
uid = (uid_t)strtol(arg, NULL, 10);
285
gid = (gid_t)strtol(arg, NULL, 10);
461
__attribute__((nonnull(3)))
462
error_t parse_opt(int key, char *arg, struct argp_state *state){
467
case 'g': /* --global-options */
470
while((plugin_option = strsep(&arg, ",")) != NULL){
471
if(not add_argument(getplugin(NULL), plugin_option)){
478
case 'G': /* --global-env */
479
if(add_environment(getplugin(NULL), arg, true)){
483
case 'o': /* --options-for */
485
char *option_list = strchr(arg, ':');
486
if(option_list == NULL){
487
argp_error(state, "No colon in \"%s\"", arg);
494
argp_error(state, "Empty plugin name");
499
while((option = strsep(&option_list, ",")) != NULL){
500
if(not add_argument(getplugin(arg), option)){
507
case 'E': /* --env-for */
509
char *envdef = strchr(arg, ':');
511
argp_error(state, "No colon in \"%s\"", arg);
518
argp_error(state, "Empty plugin name");
522
if(add_environment(getplugin(arg), envdef, true)){
527
case 'd': /* --disable */
529
plugin *p = getplugin(arg);
536
case 'e': /* --enable */
538
plugin *p = getplugin(arg);
545
case 128: /* --plugin-dir */
547
plugindir = strdup(arg);
548
if(plugindir != NULL){
552
case 129: /* --config-file */
553
/* This is already done by parse_opt_config_file() */
555
case 130: /* --userid */
556
tmp_id = strtoimax(arg, &tmp, 10);
557
if(errno != 0 or tmp == arg or *tmp != '\0'
558
or tmp_id != (uid_t)tmp_id){
559
argp_error(state, "Bad user ID number: \"%s\", using %"
560
PRIdMAX, arg, (intmax_t)uid);
566
case 131: /* --groupid */
567
tmp_id = strtoimax(arg, &tmp, 10);
568
if(errno != 0 or tmp == arg or *tmp != '\0'
569
or tmp_id != (gid_t)tmp_id){
570
argp_error(state, "Bad group ID number: \"%s\", using %"
571
PRIdMAX, arg, (intmax_t)gid);
577
case 132: /* --debug */
291
if(plus_options != NULL or arg == NULL or arg[0] != '+'){
299
return ARGP_ERR_UNKNOWN;
304
plugin *plugin_list = NULL;
306
struct argp argp = { .options = options, .parser = parse_opt,
307
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
580
case 133: /* --plugin-helper-dir */
581
free(pluginhelperdir);
582
pluginhelperdir = strdup(arg);
583
if(pluginhelperdir != NULL){
588
* These reproduce what we would get without ARGP_NO_HELP
590
case '?': /* --help */
591
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
592
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
593
__builtin_unreachable();
594
case -3: /* --usage */
595
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
596
argp_state_help(state, state->out_stream,
597
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
598
__builtin_unreachable();
599
case 'V': /* --version */
600
fprintf(state->out_stream, "%s\n", argp_program_version);
604
* When adding more options before this line, remember to also add a
605
* "case" to the "parse_opt_config_file" function below.
608
/* Cryptsetup always passes an argument, which is an empty
609
string if "none" was specified in /etc/crypttab. So if
610
argument was empty, we ignore it silently. */
615
__attribute__((fallthrough));
620
return ARGP_ERR_UNKNOWN;
622
return errno; /* Set to 0 at start */
625
/* This option parser is the same as parse_opt() above, except it
626
ignores everything but the --config-file option. */
627
error_t parse_opt_config_file(int key, char *arg,
628
__attribute__((unused))
629
struct argp_state *state){
632
case 'g': /* --global-options */
633
case 'G': /* --global-env */
634
case 'o': /* --options-for */
635
case 'E': /* --env-for */
636
case 'd': /* --disable */
637
case 'e': /* --enable */
638
case 128: /* --plugin-dir */
640
case 129: /* --config-file */
642
argfile = strdup(arg);
647
case 130: /* --userid */
648
case 131: /* --groupid */
649
case 132: /* --debug */
650
case 133: /* --plugin-helper-dir */
651
case '?': /* --help */
652
case -3: /* --usage */
653
case 'V': /* --version */
657
return ARGP_ERR_UNKNOWN;
662
struct argp argp = { .options = options,
663
.parser = parse_opt_config_file,
308
665
.doc = "Mandos plugin runner -- Run plugins" };
310
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
311
if (ret == ARGP_ERR_UNKNOWN){
312
fprintf(stderr, "Unknown error while parsing arguments\n");
313
exitstatus = EXIT_FAILURE;
318
/* This is a mangled argument in the form of
319
"+--option+--other-option=parameter+--yet-another-option", etc */
320
/* Make new argc and argv vars, and call argp_parse() again. */
321
plus_options++; /* skip the first '+' character */
322
const char delims[] = "+";
325
plus_argv = malloc(sizeof(char*) * 2);
326
if(plus_argv == NULL){
328
exitstatus = EXIT_FAILURE;
331
plus_argv[0] = argv[0];
333
arg = strtok(plus_options, delims); /* Get first argument */
336
plus_argv = realloc(plus_argv, sizeof(char *)
337
* ((unsigned int) new_argc + 1));
338
if(plus_argv == NULL){
340
exitstatus = EXIT_FAILURE;
343
plus_argv[new_argc-1] = arg;
344
plus_argv[new_argc] = NULL;
345
arg = strtok(NULL, delims); /* Get next argument */
347
ret = argp_parse (&argp, new_argc, plus_argv, 0, 0, &plugin_list);
348
if (ret == ARGP_ERR_UNKNOWN){
349
fprintf(stderr, "Unknown error while parsing arguments\n");
350
exitstatus = EXIT_FAILURE;
667
/* Parse using parse_opt_config_file() in order to get the custom
668
config file location, if any. */
669
ret = argp_parse(&argp, argc, argv,
670
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
678
error(0, errno, "argp_parse");
679
exitstatus = EX_OSERR;
682
exitstatus = EX_USAGE;
686
/* Reset to the normal argument parser */
687
argp.parser = parse_opt;
689
/* Open the configfile if available */
691
conffp = fopen(AFILE, "r");
693
conffp = fopen(argfile, "r");
696
char *org_line = NULL;
697
char *p, *arg, *new_arg, *line;
699
const char whitespace_delims[] = " \r\t\f\v\n";
700
const char comment_delim[] = "#";
703
custom_argv = malloc(sizeof(char*) * 2);
704
if(custom_argv == NULL){
705
error(0, errno, "malloc");
706
exitstatus = EX_OSERR;
709
custom_argv[0] = argv[0];
710
custom_argv[1] = NULL;
712
/* for each line in the config file, strip whitespace and ignore
715
sret = getline(&org_line, &size, conffp);
721
arg = strsep(&line, comment_delim);
722
while((p = strsep(&arg, whitespace_delims)) != NULL){
728
error(0, errno, "strdup");
729
exitstatus = EX_OSERR;
736
#if defined(__GLIBC_PREREQ) and __GLIBC_PREREQ(2, 26)
737
char **new_argv = reallocarray(custom_argv,
738
(size_t)custom_argc + 1,
741
char **new_argv = NULL;
742
if(((size_t)custom_argc + 1) > (SIZE_MAX / sizeof(char *))){
746
new_argv = realloc(custom_argv, ((size_t)custom_argc + 1)
750
if(new_argv == NULL){
751
error(0, errno, "reallocarray");
752
exitstatus = EX_OSERR;
757
custom_argv = new_argv;
760
custom_argv[custom_argc-1] = new_arg;
761
custom_argv[custom_argc] = NULL;
765
ret = fclose(conffp);
766
} while(ret == EOF and errno == EINTR);
768
error(0, errno, "fclose");
769
exitstatus = EX_IOERR;
774
/* Check for harmful errors and go to fallback. Other errors might
775
not affect opening plugins */
776
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
777
error(0, errno, "fopen");
778
exitstatus = EX_OSERR;
782
/* If there were any arguments from the configuration file, pass
783
them to parser as command line arguments */
784
if(custom_argv != NULL){
785
ret = argp_parse(&argp, custom_argc, custom_argv,
786
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
794
error(0, errno, "argp_parse");
795
exitstatus = EX_OSERR;
798
exitstatus = EX_CONFIG;
803
/* Parse actual command line arguments, to let them override the
805
ret = argp_parse(&argp, argc, argv,
806
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
814
error(0, errno, "argp_parse");
815
exitstatus = EX_OSERR;
818
exitstatus = EX_USAGE;
823
char *pluginhelperenv;
825
ret = asprintf(&pluginhelperenv, "MANDOSPLUGINHELPERDIR=%s",
826
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
828
bret = add_environment(getplugin(NULL), pluginhelperenv, true);
830
if(ret == -1 or not bret){
831
error(0, errno, "Failed to set MANDOSPLUGINHELPERDIR"
832
" environment variable to \"%s\" for all plugins\n",
833
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
836
free(pluginhelperenv);
356
for(plugin *p = plugin_list; p != NULL; p=p->next){
841
for(plugin *p = plugin_list; p != NULL; p = p->next){
357
842
fprintf(stderr, "Plugin: %s has %d arguments\n",
358
843
p->name ? p->name : "Global", p->argc - 1);
359
844
for(char **a = p->argv; *a != NULL; a++){
360
845
fprintf(stderr, "\tArg: %s\n", *a);
847
fprintf(stderr, "...and %d environment variables\n", p->envc);
848
for(char **a = p->environ; *a != NULL; a++){
849
fprintf(stderr, "\t%s\n", *a);
855
/* Work around Debian bug #633582:
856
<https://bugs.debian.org/633582> */
857
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
858
if(plugindir_fd == -1){
860
error(0, errno, "open(\"" PDIR "\")");
863
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
865
error(0, errno, "fstat");
867
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
868
ret = fchown(plugindir_fd, uid, gid);
870
error(0, errno, "fchown");
877
/* Work around Debian bug #981302
878
<https://bugs.debian.org/981302> */
879
if(lstat("/dev/fd", &st) != 0 and errno == ENOENT){
880
ret = symlink("/proc/self/fd", "/dev/fd");
882
error(0, errno, "Failed to create /dev/fd symlink");
887
/* Lower permissions */
890
error(0, errno, "setgid");
365
892
ret = setuid(uid);
375
dir = opendir(plugindir);
377
perror("Could not open plugin dir");
378
exitstatus = EXIT_FAILURE;
382
/* Set the FD_CLOEXEC flag on the directory, if possible */
894
error(0, errno, "setuid");
897
/* Open plugin directory with close_on_exec flag */
384
int dir_fd = dirfd(dir);
386
ret = set_cloexec_flag(dir_fd);
388
perror("set_cloexec_flag");
389
exitstatus = EXIT_FAILURE;
899
dir_fd = open(plugindir != NULL ? plugindir : PDIR, O_RDONLY |
902
#else /* not O_CLOEXEC */
904
#endif /* not O_CLOEXEC */
907
error(0, errno, "Could not open plugin dir");
908
exitstatus = EX_UNAVAILABLE;
913
/* Set the FD_CLOEXEC flag on the directory */
914
ret = set_cloexec_flag(dir_fd);
916
error(0, errno, "set_cloexec_flag");
917
exitstatus = EX_OSERR;
920
#endif /* O_CLOEXEC */
923
int good_name(const struct dirent * const dirent){
924
const char * const patterns[] = { ".*", "#*#", "*~", "*.dpkg-new",
925
"*.dpkg-old", "*.dpkg-bak",
926
"*.dpkg-divert", NULL };
928
#pragma GCC diagnostic push
929
#pragma GCC diagnostic ignored "-Wcast-qual"
931
for(const char **pat = (const char **)patterns;
932
*pat != NULL; pat++){
934
#pragma GCC diagnostic pop
936
if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
939
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
940
" matching pattern %s\n", dirent->d_name, *pat);
948
int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
950
if(numplugins == -1){
951
error(0, errno, "Could not scan plugin dir");
953
exitstatus = EX_OSERR;
395
957
FD_ZERO(&rfds_all);
398
dirst = readdir(dir);
400
// All directory entries have been processed
404
exitstatus = EXIT_FAILURE;
410
d_name_len = strlen(dirst->d_name);
412
// Ignore dotfiles, backup files and other junk
414
bool bad_name = false;
416
const char const *bad_prefixes[] = { ".", "#", NULL };
418
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
420
".dpkg-divert", NULL };
421
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
422
size_t pre_len = strlen(*pre);
423
if((d_name_len >= pre_len)
424
and strncmp((dirst->d_name), *pre, pre_len) == 0){
426
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
427
" with bad prefix %s\n", dirst->d_name, *pre);
438
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
439
size_t suf_len = strlen(*suf);
440
if((d_name_len >= suf_len)
441
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
444
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
445
" with bad suffix %s\n", dirst->d_name, *suf);
457
char *filename = malloc(d_name_len + strlen(plugindir) + 2);
458
if (filename == NULL){
462
strcpy(filename, plugindir); /* Spurious warning */
463
strcat(filename, "/"); /* Spurious warning */
464
strcat(filename, dirst->d_name); /* Spurious warning */
466
ret = stat(filename, &st);
473
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
959
/* Read and execute any executable in the plugin directory*/
960
for(int i = 0; i < numplugins; i++){
962
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
964
error(0, errno, "Could not open plugin");
968
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
970
error(0, errno, "stat");
976
/* Ignore non-executable files */
977
if(not S_ISREG(st.st_mode)
978
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
475
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
476
" with bad type or mode\n", filename);
981
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
982
" with bad type or mode\n",
983
plugindir != NULL ? plugindir : PDIR,
984
direntries[i]->d_name);
481
if(getplugin(dirst->d_name, &plugin_list)->disabled){
991
plugin *p = getplugin(direntries[i]->d_name);
993
error(0, errno, "getplugin");
483
1000
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
1001
direntries[i]->d_name);
1004
free(direntries[i]);
489
plugin *p = getplugin(dirst->d_name, &plugin_list);
491
1008
/* Add global arguments to argument list for this plugin */
492
plugin *g = getplugin(NULL, &plugin_list);
493
for(char **a = g->argv + 1; *a != NULL; a++){
501
exitstatus = EXIT_FAILURE;
1009
plugin *g = getplugin(NULL);
1011
for(char **a = g->argv + 1; *a != NULL; a++){
1012
if(not add_argument(p, *a)){
1013
error(0, errno, "add_argument");
1016
/* Add global environment variables */
1017
for(char **e = g->environ; *e != NULL; e++){
1018
if(not add_environment(p, *e, false)){
1019
error(0, errno, "add_environment");
1024
/* If this plugin has any environment variables, we need to
1025
duplicate the environment from this process, too. */
1026
if(p->environ[0] != NULL){
1027
for(char **e = environ; *e != NULL; e++){
1028
if(not add_environment(p, *e, false)){
1029
error(0, errno, "add_environment");
1036
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
1037
#else /* O_CLOEXEC */
1038
ret = (int)TEMP_FAILURE_RETRY(pipe2(pipefd, O_CLOEXEC));
1039
#endif /* O_CLOEXEC */
1041
error(0, errno, "pipe");
1042
exitstatus = EX_OSERR;
1043
free(direntries[i]);
1046
if(pipefd[0] >= FD_SETSIZE){
1047
fprintf(stderr, "pipe()[0] (%d) >= FD_SETSIZE (%d)", pipefd[0],
1051
exitstatus = EX_OSERR;
1052
free(direntries[i]);
1056
/* Ask OS to automatic close the pipe on exec */
504
1057
ret = set_cloexec_flag(pipefd[0]);
506
perror("set_cloexec_flag");
507
exitstatus = EXIT_FAILURE;
1059
error(0, errno, "set_cloexec_flag");
1062
exitstatus = EX_OSERR;
1063
free(direntries[i]);
510
1066
ret = set_cloexec_flag(pipefd[1]);
512
perror("set_cloexec_flag");
513
exitstatus = EXIT_FAILURE;
1068
error(0, errno, "set_cloexec_flag");
1071
exitstatus = EX_OSERR;
1072
free(direntries[i]);
1075
#endif /* not O_CLOEXEC */
516
1076
/* Block SIGCHLD until process is safely in process list */
517
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
1077
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1078
&sigchld_action.sa_mask,
519
perror("sigprocmask");
520
exitstatus = EXIT_FAILURE;
1081
error(0, errno, "sigprocmask");
1082
exitstatus = EX_OSERR;
1083
free(direntries[i]);
523
// Starting a new process to be watched
1086
/* Starting a new process to be watched */
1090
} while(pid == -1 and errno == EINTR);
527
exitstatus = EXIT_FAILURE;
1092
error(0, errno, "fork");
1093
TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1094
&sigchld_action.sa_mask, NULL));
1097
exitstatus = EX_OSERR;
1098
free(direntries[i]);
531
1102
/* this is the child process */
532
1103
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1105
error(0, errno, "sigaction");
537
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1108
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
539
perror("sigprocmask");
1110
error(0, errno, "sigprocmask");
543
1114
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1116
error(0, errno, "dup2");
550
/* If dir has no file descriptor, we could not set FD_CLOEXEC
551
above and must now close it manually here. */
554
if(execv(filename, p->argv) < 0){
1120
if(fexecve(plugin_fd, p->argv,
1121
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1122
error(0, errno, "fexecve for %s/%s",
1123
plugindir != NULL ? plugindir : PDIR,
1124
direntries[i]->d_name);
562
close(pipefd[1]); /* close unused write end of pipe */
563
process *new_process = malloc(sizeof(process));
564
if (new_process == NULL){
566
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1129
/* Parent process */
1130
close(pipefd[1]); /* Close unused write end of pipe */
1132
plugin *new_plugin = getplugin(direntries[i]->d_name);
1133
if(new_plugin == NULL){
1134
error(0, errno, "getplugin");
1135
ret = (int)(TEMP_FAILURE_RETRY
1136
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
568
perror("sigprocmask");
1139
error(0, errno, "sigprocmask");
570
exitstatus = EXIT_FAILURE;
1141
exitstatus = EX_OSERR;
1142
free(direntries[i]);
1145
free(direntries[i]);
574
*new_process = (struct process){ .pid = pid,
576
.next = process_list };
578
process_list = new_process;
1147
new_plugin->pid = pid;
1148
new_plugin->fd = pipefd[0];
1151
fprintf(stderr, "Plugin %s started (PID %" PRIdMAX ")\n",
1152
new_plugin->name, (intmax_t) (new_plugin->pid));
579
1155
/* Unblock SIGCHLD so signal handler can be run if this process
580
1156
has already completed */
581
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1157
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1158
&sigchld_action.sa_mask,
583
perror("sigprocmask");
584
exitstatus = EXIT_FAILURE;
588
FD_SET(new_process->fd, &rfds_all);
590
if (maxfd < new_process->fd){
591
maxfd = new_process->fd;
596
/* Free the plugin list */
597
for(plugin *next; plugin_list != NULL; plugin_list = next){
598
next = plugin_list->next;
599
free(plugin_list->argv);
606
if (process_list == NULL){
607
fprintf(stderr, "No plugin processes started. Incorrect plugin"
1161
error(0, errno, "sigprocmask");
1162
exitstatus = EX_OSERR;
1166
FD_SET(new_plugin->fd, &rfds_all);
1168
if(maxfd < new_plugin->fd){
1169
maxfd = new_plugin->fd;
1177
free_plugin(getplugin(NULL));
1179
for(plugin *p = plugin_list; p != NULL; p = p->next){
1183
if(p->next == NULL){
1184
fprintf(stderr, "No plugin processes started. Incorrect plugin"
1190
/* Main loop while running plugins exist */
612
1192
fd_set rfds = rfds_all;
613
1193
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
614
if (select_ret == -1){
616
exitstatus = EXIT_FAILURE;
1194
if(select_ret == -1 and errno != EINTR){
1195
error(0, errno, "select");
1196
exitstatus = EX_OSERR;
619
1199
/* OK, now either a process completed, or something can be read
620
1200
from one of them */
621
for(process *proc = process_list; proc ; proc = proc->next){
1201
for(plugin *proc = plugin_list; proc != NULL;){
622
1202
/* Is this process completely done? */
623
if(proc->eof and proc->completed){
1203
if(proc->completed and proc->eof){
624
1204
/* Only accept the plugin output if it exited cleanly */
625
1205
if(not WIFEXITED(proc->status)
626
1206
or WEXITSTATUS(proc->status) != 0){
627
1207
/* Bad exit by plugin */
629
1210
if(WIFEXITED(proc->status)){
630
fprintf(stderr, "Plugin %u exited with status %d\n",
631
(unsigned int) (proc->pid),
1211
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1212
" status %d\n", proc->name,
1213
(intmax_t) (proc->pid),
632
1214
WEXITSTATUS(proc->status));
633
} else if(WIFSIGNALED(proc->status)) {
634
fprintf(stderr, "Plugin %u killed by signal %d\n",
635
(unsigned int) (proc->pid),
636
WTERMSIG(proc->status));
637
} else if(WCOREDUMP(proc->status)){
638
fprintf(stderr, "Plugin %d dumped core\n",
639
(unsigned int) (proc->pid));
1215
} else if(WIFSIGNALED(proc->status)){
1216
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1217
" signal %d: %s\n", proc->name,
1218
(intmax_t) (proc->pid),
1219
WTERMSIG(proc->status),
1220
strsignal(WTERMSIG(proc->status)));
642
1224
/* Remove the plugin */
643
1225
FD_CLR(proc->fd, &rfds_all);
644
1227
/* Block signal while modifying process_list */
645
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
1228
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1230
&sigchld_action.sa_mask,
647
perror("sigprocmask");
648
exitstatus = EXIT_FAILURE;
651
/* Delete this process entry from the list */
652
if(process_list == proc){
653
/* First one - simple */
654
process_list = proc->next;
656
/* Second one or later */
657
for(process *p = process_list; p != NULL; p = p->next){
659
p->next = proc->next;
1233
error(0, errno, "sigprocmask");
1234
exitstatus = EX_OSERR;
1238
plugin *next_plugin = proc->next;
664
1242
/* We are done modifying process list, so unblock signal */
665
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
1243
ret = (int)(TEMP_FAILURE_RETRY
1244
(sigprocmask(SIG_UNBLOCK,
1245
&sigchld_action.sa_mask, NULL)));
668
perror("sigprocmask");
672
/* We deleted this process from the list, so we can't go
673
proc->next. Therefore, start over from the beginning of
1247
error(0, errno, "sigprocmask");
1248
exitstatus = EX_OSERR;
1252
if(plugin_list == NULL){
677
1259
/* This process exited nicely, so print its buffer */
679
bool bret = print_out_password(proc->buffer, proc->buffer_length);
1261
bool bret = print_out_password(proc->buffer,
1262
proc->buffer_length);
681
perror("print_out_password");
682
exitstatus = EXIT_FAILURE;
1264
error(0, errno, "print_out_password");
1265
exitstatus = EX_IOERR;
686
1270
/* This process has not completed. Does it have any output? */
687
1271
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
688
1272
/* This process had nothing to say at this time */
691
1276
/* Before reading, make the process' data buffer large enough */
692
1277
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
693
proc->buffer = realloc(proc->buffer, proc->buffer_size
694
+ (size_t) BUFFER_SIZE);
695
if (proc->buffer == NULL){
697
exitstatus = EXIT_FAILURE;
1278
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1279
+ (size_t) BUFFER_SIZE);
1280
if(new_buffer == NULL){
1281
error(0, errno, "malloc");
1282
exitstatus = EX_OSERR;
1285
proc->buffer = new_buffer;
700
1286
proc->buffer_size += BUFFER_SIZE;
702
1288
/* Read from the process */
703
ret = read(proc->fd, proc->buffer + proc->buffer_length,
1289
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1291
+ proc->buffer_length,
706
1294
/* Read error from this process; ignore the error */
711
1300
proc->eof = true;
713
proc->buffer_length += (size_t) ret;
1302
proc->buffer_length += (size_t) sret;
721
if(process_list == NULL or exitstatus != EXIT_SUCCESS){
722
/* Fallback if all plugins failed, none are found or an error occured */
1310
if(plugin_list == NULL or (exitstatus != EXIT_SUCCESS
1311
and exitstatus != EX_OK)){
1312
/* Fallback if all plugins failed, none are found or an error
724
1315
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
725
1316
char *passwordbuffer = getpass("Password: ");
726
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
1317
size_t len = strlen(passwordbuffer);
1318
/* Strip trailing newline */
1319
if(len > 0 and passwordbuffer[len-1] == '\n'){
1320
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1323
bret = print_out_password(passwordbuffer, len);
728
perror("print_out_password");
729
exitstatus = EXIT_FAILURE;
1325
error(0, errno, "print_out_password");
1326
exitstatus = EX_IOERR;
734
1330
/* Restore old signal handler */
735
sigaction(SIGCHLD, &old_sigchld_action, NULL);
739
/* Free the plugin list */
740
for(plugin *next; plugin_list != NULL; plugin_list = next){
741
next = plugin_list->next;
742
free(plugin_list->argv);
750
/* Free the process list and kill the processes */
751
for(process *next; process_list != NULL; process_list = next){
752
next = process_list->next;
753
close(process_list->fd);
754
ret = kill(process_list->pid, SIGTERM);
755
if(ret == -1 and errno != ESRCH){
756
/* set-uid proccesses migth not get closed */
759
free(process_list->buffer);
1331
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1333
error(0, errno, "sigaction");
1334
exitstatus = EX_OSERR;
1337
if(custom_argv != NULL){
1338
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1350
/* Kill the processes */
1351
for(plugin *p = plugin_list; p != NULL; p = p->next){
1354
ret = kill(p->pid, SIGTERM);
1355
if(ret == -1 and errno != ESRCH){
1356
/* Set-uid proccesses might not get closed */
1357
error(0, errno, "kill");
763
1362
/* Wait for any remaining child processes to terminate */
765
1364
ret = wait(NULL);
766
1365
} while(ret >= 0);
767
1366
if(errno != ECHILD){
1367
error(0, errno, "wait");
1373
free(pluginhelperdir);
771
1376
return exitstatus;