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/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
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/* -*- coding: utf-8 -*- */
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* Mandos plugin runner - Run Mandos plugins
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* Copyright © 2008-2018 Teddy Hogeborn
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* Copyright © 2008-2018 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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* Copyright © 2007-2008 Teddy Hogeborn and 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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* WITHOUT ANY WARRANTY; without even the implied warranty of
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14
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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15
* General Public License for more details.
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* You should have received a copy of the GNU General Public License
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* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
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* along with this program. If not, see
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* <http://www.gnu.org/licenses/>.
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* Contact the authors at <mandos@recompile.se>.
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* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
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* <https://www.fukt.bsnet.se/~teddy/>.
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#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
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#include <stddef.h> /* size_t, NULL */
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#include <stdlib.h> /* malloc(), exit(), EXIT_SUCCESS,
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#include <stdbool.h> /* bool, true, false */
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#include <stdio.h> /* fileno(), fprintf(),
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stderr, STDOUT_FILENO, fclose() */
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#include <sys/types.h> /* fstat(), struct stat, waitpid(),
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WIFEXITED(), WEXITSTATUS(), wait(),
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pid_t, uid_t, gid_t, getuid(),
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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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#include <sys/stat.h> /* struct stat, fstat(), S_ISREG() */
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#include <iso646.h> /* and, or, not */
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#include <dirent.h> /* struct dirent, scandirat() */
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#include <unistd.h> /* fcntl(), F_GETFD, F_SETFD,
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FD_CLOEXEC, write(), STDOUT_FILENO,
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struct stat, fstat(), close(),
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setgid(), setuid(), S_ISREG(),
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faccessat() pipe2(), fork(),
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_exit(), dup2(), fexecve(), read()
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#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
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FD_CLOEXEC, openat(), scandirat(),
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#include <string.h> /* strsep, strlen(), strsignal(),
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strcmp(), strncmp() */
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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,
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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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#include <errno.h> /* errno, EBADF */
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#include <inttypes.h> /* intmax_t, PRIdMAX, strtoimax() */
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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 <errno.h> /* errno */
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#include <error.h> /* error() */
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#include <fnmatch.h> /* fnmatch() */
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#define BUFFER_SIZE 256
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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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#define _FORTIFY_SOURCE 2
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#include <stdio.h> /* popen, fileno */
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#include <iso646.h> /* and, or, not */
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#include <sys/types.h> /* DIR, opendir, stat, struct stat, waitpid,
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WIFEXITED, WEXITSTATUS, wait */
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#include <sys/wait.h> /* wait */
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#include <dirent.h> /* DIR, opendir */
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#include <sys/stat.h> /* stat, struct stat */
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#include <unistd.h> /* stat, struct stat, chdir */
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#include <stdlib.h> /* EXIT_FAILURE */
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#include <sys/select.h> /* fd_set, select, FD_ZERO, FD_SET,
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#include <string.h> /* strlen, strcpy, strcat */
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#include <stdbool.h> /* true */
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#include <sys/wait.h> /* waitpid, WIFEXITED, WEXITSTATUS */
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#include <errno.h> /* errno */
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#include <argp.h> /* argp */
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typedef struct process{
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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 "global" and any plugin name */
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struct plugin *next;
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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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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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/* Create a new plugin */
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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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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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new_plugin->argv[1] = NULL;
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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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new_plugin->disable = false;
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new_plugin->next = *plugin_list;
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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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/* 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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new_array = realloc(*array, sizeof(char *)
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* (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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* Based on the example in the GNU LibC manual chapter 13.13 "File
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| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
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__attribute__((warn_unused_result))
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static int set_cloexec_flag(int fd){
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int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
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/* If reading the flags failed, return error indication now. */
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/* Store modified flag word in the descriptor. */
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return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
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#endif /* not O_CLOEXEC */
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/* Mark processes as completed when they exit, and save their exit
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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 */
278
/* No child processes */
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error(0, errno, "waitpid");
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/* 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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/* 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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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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/* Removes and free a plugin from the plugin list */
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__attribute__((nonnull))
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static void free_plugin(plugin *plugin_node){
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for(char **arg = (plugin_node->argv)+1; *arg != NULL; arg++){
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free(plugin_node->name);
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free(plugin_node->argv);
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for(char **env = plugin_node->environ; *env != NULL; env++){
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free(plugin_node->environ);
325
free(plugin_node->buffer);
327
/* Removes the plugin from the singly-linked list */
328
if(plugin_node == plugin_list){
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/* First one - simple */
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plugin_list = plugin_list->next;
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/* Second one or later */
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for(plugin *p = plugin_list; p != NULL; p = p->next){
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if(p->next == plugin_node){
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p->next = plugin_node->next;
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static void free_plugin_list(void){
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while(plugin_list != NULL){
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free_plugin(plugin_list);
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void addarguments(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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p->argv[p->argc] = NULL;
103
#define BUFFER_SIZE 256
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const char *argp_program_version =
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"plugbasedclient 0.9";
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const char *argp_program_bug_address =
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"<mandos@fukt.bsnet.se>";
110
"Mandos plugin runner -- Run Mandos plugins";
111
/* A description of the arguments we accept. */
112
static char args_doc[] = "";
350
114
int main(int argc, char *argv[]){
351
char *plugindir = NULL;
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char *pluginhelperdir = NULL;
353
char *argfile = NULL;
355
struct dirent **direntries = NULL;
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const char *plugindir = "plugins.d";
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struct dirent *dirst;
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int ret, maxfd = 0;
122
process *process_list = NULL;
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123
uid_t uid = 65534;
361
124
gid_t gid = 65534;
363
int exitstatus = EXIT_SUCCESS;
364
struct sigaction old_sigchld_action;
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struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
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.sa_flags = SA_NOCLDSTOP };
367
char **custom_argv = NULL;
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/* Establish a signal handler */
372
sigemptyset(&sigchld_action.sa_mask);
373
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
375
error(0, errno, "sigaddset");
376
exitstatus = EX_OSERR;
379
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
381
error(0, errno, "sigaction");
382
exitstatus = EX_OSERR;
386
125
/* The options we understand. */
387
126
struct argp_option options[] = {
388
127
{ .name = "global-options", .key = 'g',
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.arg = "OPTION[,OPTION[,...]]",
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.doc = "Options passed to all plugins" },
391
{ .name = "global-env", .key = 'G',
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.doc = "Environment variable passed to all plugins" },
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.arg = "option[,option[,...]]", .flags = 0,
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.doc = "Options effecting 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",
399
.doc = "Environment variable passed to specified plugin" },
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{ .name = "disable", .key = 'd',
402
.doc = "Disable a specific plugin", .group = 1 },
403
{ .name = "enable", .key = 'e',
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.doc = "Enable a specific plugin", .group = 1 },
131
.arg = "plugin:option[,option[,...]]", .flags = 0,
132
.doc = "Options effecting only specified plugins" },
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{ .name = "disable-plugin", .key = 'd',
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.arg = "Plugin[,Plugin[,...]]", .flags = 0,
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.doc = "Option to disable specififed plugins" },
406
136
{ .name = "plugin-dir", .key = 128,
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.doc = "Specify a different plugin directory", .group = 2 },
409
{ .name = "config-file", .key = 129,
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.doc = "Specify a different configuration file", .group = 2 },
412
{ .name = "userid", .key = 130,
413
.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,
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.arg = "ID", .flags = 0,
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.doc = "Group ID the plugins will run as", .group = 3 },
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{ .name = "debug", .key = 132,
419
.doc = "Debug mode", .group = 4 },
420
{ .name = "plugin-helper-dir", .key = 133,
422
.doc = "Specify a different plugin helper directory",
425
* These reproduce what we would get without ARGP_NO_HELP
427
{ .name = "help", .key = '?',
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.doc = "Give this help list", .group = -1 },
429
{ .name = "usage", .key = -3,
430
.doc = "Give a short usage message", .group = -1 },
431
{ .name = "version", .key = 'V',
432
.doc = "Print program version", .group = -1 },
137
.arg = "Directory", .flags = 0,
138
.doc = "Option to change directory to search for plugins" },
139
{ .name = "userid", .key = 129,
140
.arg = "Id", .flags = 0,
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.doc = "Option to change which user id the plugins will run as" },
142
{ .name = "groupid", .key = 130,
143
.arg = "Id", .flags = 0,
144
.doc = "Option to change which group id the plugins will run as" },
436
__attribute__((nonnull(3)))
437
error_t parse_opt(int key, char *arg, struct argp_state *state){
442
case 'g': /* --global-options */
445
while((plugin_option = strsep(&arg, ",")) != NULL){
446
if(not add_argument(getplugin(NULL), plugin_option)){
453
case 'G': /* --global-env */
454
if(add_environment(getplugin(NULL), arg, true)){
458
case 'o': /* --options-for */
460
char *option_list = strchr(arg, ':');
461
if(option_list == NULL){
462
argp_error(state, "No colon in \"%s\"", arg);
469
argp_error(state, "Empty plugin name");
474
while((option = strsep(&option_list, ",")) != NULL){
475
if(not add_argument(getplugin(arg), option)){
482
case 'E': /* --env-for */
484
char *envdef = strchr(arg, ':');
486
argp_error(state, "No colon in \"%s\"", arg);
493
argp_error(state, "Empty plugin name");
497
if(add_environment(getplugin(arg), envdef, true)){
502
case 'd': /* --disable */
504
plugin *p = getplugin(arg);
511
case 'e': /* --enable */
513
plugin *p = getplugin(arg);
520
case 128: /* --plugin-dir */
522
plugindir = strdup(arg);
523
if(plugindir != NULL){
527
case 129: /* --config-file */
528
/* This is already done by parse_opt_config_file() */
530
case 130: /* --userid */
531
tmp_id = strtoimax(arg, &tmp, 10);
532
if(errno != 0 or tmp == arg or *tmp != '\0'
533
or tmp_id != (uid_t)tmp_id){
534
argp_error(state, "Bad user ID number: \"%s\", using %"
535
PRIdMAX, arg, (intmax_t)uid);
541
case 131: /* --groupid */
542
tmp_id = strtoimax(arg, &tmp, 10);
543
if(errno != 0 or tmp == arg or *tmp != '\0'
544
or tmp_id != (gid_t)tmp_id){
545
argp_error(state, "Bad group ID number: \"%s\", using %"
546
PRIdMAX, arg, (intmax_t)gid);
552
case 132: /* --debug */
555
case 133: /* --plugin-helper-dir */
556
free(pluginhelperdir);
557
pluginhelperdir = strdup(arg);
558
if(pluginhelperdir != NULL){
563
* These reproduce what we would get without ARGP_NO_HELP
565
case '?': /* --help */
566
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
567
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
568
__builtin_unreachable();
569
case -3: /* --usage */
570
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
571
argp_state_help(state, state->out_stream,
572
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
573
__builtin_unreachable();
574
case 'V': /* --version */
575
fprintf(state->out_stream, "%s\n", argp_program_version);
579
* When adding more options before this line, remember to also add a
580
* "case" to the "parse_opt_config_file" function below.
583
/* Cryptsetup always passes an argument, which is an empty
584
string if "none" was specified in /etc/crypttab. So if
585
argument was empty, we ignore it silently. */
590
__attribute__((fallthrough));
595
return ARGP_ERR_UNKNOWN;
597
return errno; /* Set to 0 at start */
600
/* This option parser is the same as parse_opt() above, except it
601
ignores everything but the --config-file option. */
602
error_t parse_opt_config_file(int key, char *arg,
603
__attribute__((unused))
604
struct argp_state *state){
607
case 'g': /* --global-options */
608
case 'G': /* --global-env */
609
case 'o': /* --options-for */
610
case 'E': /* --env-for */
611
case 'd': /* --disable */
612
case 'e': /* --enable */
613
case 128: /* --plugin-dir */
615
case 129: /* --config-file */
617
argfile = strdup(arg);
622
case 130: /* --userid */
623
case 131: /* --groupid */
624
case 132: /* --debug */
625
case 133: /* --plugin-helper-dir */
626
case '?': /* --help */
627
case -3: /* --usage */
628
case 'V': /* --version */
632
return ARGP_ERR_UNKNOWN;
637
struct argp argp = { .options = options,
638
.parser = parse_opt_config_file,
640
.doc = "Mandos plugin runner -- Run plugins" };
642
/* Parse using parse_opt_config_file() in order to get the custom
643
config file location, if any. */
644
ret = argp_parse(&argp, argc, argv,
645
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
653
error(0, errno, "argp_parse");
654
exitstatus = EX_OSERR;
657
exitstatus = EX_USAGE;
661
/* Reset to the normal argument parser */
662
argp.parser = parse_opt;
664
/* Open the configfile if available */
666
conffp = fopen(AFILE, "r");
668
conffp = fopen(argfile, "r");
671
char *org_line = NULL;
672
char *p, *arg, *new_arg, *line;
674
const char whitespace_delims[] = " \r\t\f\v\n";
675
const char comment_delim[] = "#";
678
custom_argv = malloc(sizeof(char*) * 2);
679
if(custom_argv == NULL){
680
error(0, errno, "malloc");
681
exitstatus = EX_OSERR;
684
custom_argv[0] = argv[0];
685
custom_argv[1] = NULL;
687
/* for each line in the config file, strip whitespace and ignore
690
sret = getline(&org_line, &size, conffp);
696
arg = strsep(&line, comment_delim);
697
while((p = strsep(&arg, whitespace_delims)) != NULL){
703
error(0, errno, "strdup");
704
exitstatus = EX_OSERR;
711
char **new_argv = realloc(custom_argv, sizeof(char *)
712
* ((size_t)custom_argc + 1));
713
if(new_argv == NULL){
714
error(0, errno, "realloc");
715
exitstatus = EX_OSERR;
720
custom_argv = new_argv;
723
custom_argv[custom_argc-1] = new_arg;
724
custom_argv[custom_argc] = NULL;
728
ret = fclose(conffp);
729
} while(ret == EOF and errno == EINTR);
731
error(0, errno, "fclose");
732
exitstatus = EX_IOERR;
737
/* Check for harmful errors and go to fallback. Other errors might
738
not affect opening plugins */
739
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
740
error(0, errno, "fopen");
741
exitstatus = EX_OSERR;
745
/* If there were any arguments from the configuration file, pass
746
them to parser as command line arguments */
747
if(custom_argv != NULL){
748
ret = argp_parse(&argp, custom_argc, custom_argv,
749
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
757
error(0, errno, "argp_parse");
758
exitstatus = EX_OSERR;
761
exitstatus = EX_CONFIG;
766
/* Parse actual command line arguments, to let them override the
768
ret = argp_parse(&argp, argc, argv,
769
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
777
error(0, errno, "argp_parse");
778
exitstatus = EX_OSERR;
781
exitstatus = EX_USAGE;
786
char *pluginhelperenv;
788
ret = asprintf(&pluginhelperenv, "MANDOSPLUGINHELPERDIR=%s",
789
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
791
bret = add_environment(getplugin(NULL), pluginhelperenv, true);
793
if(ret == -1 or not bret){
794
error(0, errno, "Failed to set MANDOSPLUGINHELPERDIR"
795
" environment variable to \"%s\" for all plugins\n",
796
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
799
free(pluginhelperenv);
804
for(plugin *p = plugin_list; p != NULL; p = p->next){
805
fprintf(stderr, "Plugin: %s has %d arguments\n",
806
p->name ? p->name : "Global", p->argc - 1);
807
for(char **a = p->argv; *a != NULL; a++){
808
fprintf(stderr, "\tArg: %s\n", *a);
810
fprintf(stderr, "...and %d environment variables\n", p->envc);
811
for(char **a = p->environ; *a != NULL; a++){
812
fprintf(stderr, "\t%s\n", *a);
818
/* Work around Debian bug #633582:
819
<https://bugs.debian.org/633582> */
820
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
821
if(plugindir_fd == -1){
823
error(0, errno, "open(\"" PDIR "\")");
826
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
828
error(0, errno, "fstat");
830
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
831
ret = fchown(plugindir_fd, uid, gid);
833
error(0, errno, "fchown");
841
/* Lower permissions */
844
error(0, errno, "setgid");
148
error_t parse_opt (int key, char *arg, struct argp_state *state) {
149
/* Get the INPUT argument from `argp_parse', which we
150
know is a pointer to our arguments structure. */
151
plugin **plugins = state->input;
155
char *p = strtok(arg, ",");
157
addarguments(getplugin(NULL, plugins), p);
158
p = strtok(NULL, ",");
164
char *name = strtok(arg, ":");
165
char *p = strtok(NULL, ":");
168
addarguments(getplugin(name, plugins), p);
169
p = strtok(NULL, ",");
175
char *p = strtok(arg, ",");
177
getplugin(p, plugins)->disable = true;
178
p = strtok(NULL, ",");
186
uid = (uid_t)strtol(arg, NULL, 10);
189
gid = (gid_t)strtol(arg, NULL, 10);
197
return ARGP_ERR_UNKNOWN;
202
plugin *plugin_list = NULL;
204
struct argp argp = { .options = options, .parser = parse_opt,
205
.args_doc = args_doc, .doc = doc };
207
argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
209
/* for(plugin *p = plugin_list; p != NULL; p=p->next){ */
210
/* fprintf(stderr, "Plugin: %s has %d arguments\n", p->name ? p->name : "Global", p->argc); */
211
/* for(char **a = p->argv + 1; *a != NULL; a++){ */
212
/* fprintf(stderr, "\tArg: %s\n", *a); */
846
218
ret = setuid(uid);
848
error(0, errno, "setuid");
851
/* Open plugin directory with close_on_exec flag */
853
dir_fd = open(plugindir != NULL ? plugindir : PDIR, O_RDONLY |
856
#else /* not O_CLOEXEC */
858
#endif /* not O_CLOEXEC */
861
error(0, errno, "Could not open plugin dir");
862
exitstatus = EX_UNAVAILABLE;
867
/* Set the FD_CLOEXEC flag on the directory */
868
ret = set_cloexec_flag(dir_fd);
870
error(0, errno, "set_cloexec_flag");
871
exitstatus = EX_OSERR;
874
#endif /* O_CLOEXEC */
877
int good_name(const struct dirent * const dirent){
878
const char * const patterns[] = { ".*", "#*#", "*~", "*.dpkg-new",
879
"*.dpkg-old", "*.dpkg-bak",
880
"*.dpkg-divert", NULL };
882
#pragma GCC diagnostic push
883
#pragma GCC diagnostic ignored "-Wcast-qual"
885
for(const char **pat = (const char **)patterns;
886
*pat != NULL; pat++){
888
#pragma GCC diagnostic pop
890
if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
893
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
894
" matching pattern %s\n", dirent->d_name, *pat);
902
int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
904
if(numplugins == -1){
905
error(0, errno, "Could not scan plugin dir");
907
exitstatus = EX_OSERR;
913
/* Read and execute any executable in the plugin directory*/
914
for(int i = 0; i < numplugins; i++){
916
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
918
error(0, errno, "Could not open plugin");
922
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
924
error(0, errno, "stat");
930
/* Ignore non-executable files */
931
if(not S_ISREG(st.st_mode)
932
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
935
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
936
" with bad type or mode\n",
937
plugindir != NULL ? plugindir : PDIR,
938
direntries[i]->d_name);
945
plugin *p = getplugin(direntries[i]->d_name);
947
error(0, errno, "getplugin");
954
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
955
direntries[i]->d_name);
962
/* Add global arguments to argument list for this plugin */
963
plugin *g = getplugin(NULL);
228
dir = opendir(plugindir);
231
fprintf(stderr, "Can not open directory\n");
238
dirst = readdir(dir);
240
// All directory entries have been processed
245
d_name_len = strlen(dirst->d_name);
247
// Ignore dotfiles and backup files
248
if (dirst->d_name[0] == '.'
249
or dirst->d_name[d_name_len - 1] == '~'){
253
char *filename = malloc(d_name_len + strlen(plugindir) + 2);
254
strcpy(filename, plugindir);
255
strcat(filename, "/");
256
strcat(filename, dirst->d_name);
260
if (S_ISREG(st.st_mode)
261
and (access(filename, X_OK) == 0)
262
and not (getplugin(dirst->d_name, &plugin_list)->disable)){
263
// Starting a new process to be watched
264
process *new_process = malloc(sizeof(process));
271
new_process->pid = fork();
272
if(new_process->pid == 0){
273
/* this is the child process */
275
close(pipefd[0]); /* close unused read end of pipe */
276
dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
278
plugin *p = getplugin(dirst->d_name, &plugin_list);
279
plugin *g = getplugin(NULL, &plugin_list);
965
280
for(char **a = g->argv + 1; *a != NULL; a++){
966
if(not add_argument(p, *a)){
967
error(0, errno, "add_argument");
970
/* Add global environment variables */
971
for(char **e = g->environ; *e != NULL; e++){
972
if(not add_environment(p, *e, false)){
973
error(0, errno, "add_environment");
978
/* If this plugin has any environment variables, we need to
979
duplicate the environment from this process, too. */
980
if(p->environ[0] != NULL){
981
for(char **e = environ; *e != NULL; e++){
982
if(not add_environment(p, *e, false)){
983
error(0, errno, "add_environment");
990
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
991
#else /* O_CLOEXEC */
992
ret = (int)TEMP_FAILURE_RETRY(pipe2(pipefd, O_CLOEXEC));
993
#endif /* O_CLOEXEC */
995
error(0, errno, "pipe");
996
exitstatus = EX_OSERR;
1000
if(pipefd[0] >= FD_SETSIZE){
1001
fprintf(stderr, "pipe()[0] (%d) >= FD_SETSIZE (%d)", pipefd[0],
1005
exitstatus = EX_OSERR;
1006
free(direntries[i]);
1010
/* Ask OS to automatic close the pipe on exec */
1011
ret = set_cloexec_flag(pipefd[0]);
1013
error(0, errno, "set_cloexec_flag");
1016
exitstatus = EX_OSERR;
1017
free(direntries[i]);
1020
ret = set_cloexec_flag(pipefd[1]);
1022
error(0, errno, "set_cloexec_flag");
1025
exitstatus = EX_OSERR;
1026
free(direntries[i]);
1029
#endif /* not O_CLOEXEC */
1030
/* Block SIGCHLD until process is safely in process list */
1031
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1032
&sigchld_action.sa_mask,
1035
error(0, errno, "sigprocmask");
1036
exitstatus = EX_OSERR;
1037
free(direntries[i]);
1040
/* Starting a new process to be watched */
1044
} while(pid == -1 and errno == EINTR);
1046
error(0, errno, "fork");
1047
TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1048
&sigchld_action.sa_mask, NULL));
1051
exitstatus = EX_OSERR;
1052
free(direntries[i]);
1056
/* this is the child process */
1057
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1059
error(0, errno, "sigaction");
1062
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1064
error(0, errno, "sigprocmask");
1068
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1070
error(0, errno, "dup2");
1074
if(fexecve(plugin_fd, p->argv,
1075
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1076
error(0, errno, "fexecve for %s/%s",
1077
plugindir != NULL ? plugindir : PDIR,
1078
direntries[i]->d_name);
1083
/* Parent process */
1084
close(pipefd[1]); /* Close unused write end of pipe */
1086
plugin *new_plugin = getplugin(direntries[i]->d_name);
1087
if(new_plugin == NULL){
1088
error(0, errno, "getplugin");
1089
ret = (int)(TEMP_FAILURE_RETRY
1090
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1093
error(0, errno, "sigprocmask");
1095
exitstatus = EX_OSERR;
1096
free(direntries[i]);
1099
free(direntries[i]);
1101
new_plugin->pid = pid;
1102
new_plugin->fd = pipefd[0];
1105
fprintf(stderr, "Plugin %s started (PID %" PRIdMAX ")\n",
1106
new_plugin->name, (intmax_t) (new_plugin->pid));
1109
/* Unblock SIGCHLD so signal handler can be run if this process
1110
has already completed */
1111
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1112
&sigchld_action.sa_mask,
1115
error(0, errno, "sigprocmask");
1116
exitstatus = EX_OSERR;
1120
FD_SET(new_plugin->fd, &rfds_all);
1122
if(maxfd < new_plugin->fd){
1123
maxfd = new_plugin->fd;
1131
free_plugin(getplugin(NULL));
1133
for(plugin *p = plugin_list; p != NULL; p = p->next){
283
if(execv(filename, p->argv) < 0){
290
close(pipefd[1]); /* close unused write end of pipe */
291
new_process->fd = pipefd[0];
292
new_process->buffer = malloc(BUFFER_SIZE);
293
if (new_process->buffer == NULL){
297
new_process->buffer_size = BUFFER_SIZE;
298
new_process->buffer_length = 0;
299
FD_SET(new_process->fd, &rfds_orig);
301
if (maxfd < new_process->fd){
302
maxfd = new_process->fd;
306
new_process->next = process_list;
307
process_list = new_process;
313
if (process_list != NULL){
315
fd_set rfds = rfds_orig;
316
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
317
if (select_ret == -1){
321
for(process *process_itr = process_list; process_itr != NULL;
322
process_itr = process_itr->next){
323
if(FD_ISSET(process_itr->fd, &rfds)){
324
if(process_itr->buffer_length + BUFFER_SIZE
325
> process_itr->buffer_size){
326
process_itr->buffer = realloc(process_itr->buffer,
327
process_itr->buffer_size
328
+ (size_t) BUFFER_SIZE);
329
if (process_itr->buffer == NULL){
333
process_itr->buffer_size += BUFFER_SIZE;
335
ret = read(process_itr->fd, process_itr->buffer
336
+ process_itr->buffer_length, BUFFER_SIZE);
338
/* Read error from this process; ignore it */
341
process_itr->buffer_length += (size_t) ret;
344
/* wait for process exit */
346
waitpid(process_itr->pid, &status, 0);
347
if(WIFEXITED(status) and WEXITSTATUS(status) == 0){
348
for(size_t written = 0;
349
written < process_itr->buffer_length;){
350
ret = write(STDOUT_FILENO,
351
process_itr->buffer + written,
352
process_itr->buffer_length - written);
357
written += (size_t)ret;
361
FD_CLR(process_itr->fd, &rfds_orig);
371
for(process *process_itr = process_list; process_itr != NULL;
372
process_itr = process_itr->next){
373
close(process_itr->fd);
374
kill(process_itr->pid, SIGTERM);
375
free(process_itr->buffer);
1137
if(p->next == NULL){
1138
fprintf(stderr, "No plugin processes started. Incorrect plugin"
1144
/* Main loop while running plugins exist */
1146
fd_set rfds = rfds_all;
1147
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
1148
if(select_ret == -1 and errno != EINTR){
1149
error(0, errno, "select");
1150
exitstatus = EX_OSERR;
1153
/* OK, now either a process completed, or something can be read
1155
for(plugin *proc = plugin_list; proc != NULL;){
1156
/* Is this process completely done? */
1157
if(proc->completed and proc->eof){
1158
/* Only accept the plugin output if it exited cleanly */
1159
if(not WIFEXITED(proc->status)
1160
or WEXITSTATUS(proc->status) != 0){
1161
/* Bad exit by plugin */
1164
if(WIFEXITED(proc->status)){
1165
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1166
" status %d\n", proc->name,
1167
(intmax_t) (proc->pid),
1168
WEXITSTATUS(proc->status));
1169
} else if(WIFSIGNALED(proc->status)){
1170
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1171
" signal %d: %s\n", proc->name,
1172
(intmax_t) (proc->pid),
1173
WTERMSIG(proc->status),
1174
strsignal(WTERMSIG(proc->status)));
1178
/* Remove the plugin */
1179
FD_CLR(proc->fd, &rfds_all);
1181
/* Block signal while modifying process_list */
1182
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1184
&sigchld_action.sa_mask,
1187
error(0, errno, "sigprocmask");
1188
exitstatus = EX_OSERR;
1192
plugin *next_plugin = proc->next;
1196
/* We are done modifying process list, so unblock signal */
1197
ret = (int)(TEMP_FAILURE_RETRY
1198
(sigprocmask(SIG_UNBLOCK,
1199
&sigchld_action.sa_mask, NULL)));
1201
error(0, errno, "sigprocmask");
1202
exitstatus = EX_OSERR;
1206
if(plugin_list == NULL){
1213
/* This process exited nicely, so print its buffer */
1215
bool bret = print_out_password(proc->buffer,
1216
proc->buffer_length);
1218
error(0, errno, "print_out_password");
1219
exitstatus = EX_IOERR;
1224
/* This process has not completed. Does it have any output? */
1225
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1226
/* This process had nothing to say at this time */
1230
/* Before reading, make the process' data buffer large enough */
1231
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1232
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1233
+ (size_t) BUFFER_SIZE);
1234
if(new_buffer == NULL){
1235
error(0, errno, "malloc");
1236
exitstatus = EX_OSERR;
1239
proc->buffer = new_buffer;
1240
proc->buffer_size += BUFFER_SIZE;
1242
/* Read from the process */
1243
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1245
+ proc->buffer_length,
1248
/* Read error from this process; ignore the error */
1256
proc->buffer_length += (size_t) sret;
1264
if(plugin_list == NULL or (exitstatus != EXIT_SUCCESS
1265
and exitstatus != EX_OK)){
1266
/* Fallback if all plugins failed, none are found or an error
1269
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1270
char *passwordbuffer = getpass("Password: ");
1271
size_t len = strlen(passwordbuffer);
1272
/* Strip trailing newline */
1273
if(len > 0 and passwordbuffer[len-1] == '\n'){
1274
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1277
bret = print_out_password(passwordbuffer, len);
1279
error(0, errno, "print_out_password");
1280
exitstatus = EX_IOERR;
1284
/* Restore old signal handler */
1285
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1287
error(0, errno, "sigaction");
1288
exitstatus = EX_OSERR;
1291
if(custom_argv != NULL){
1292
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1304
/* Kill the processes */
1305
for(plugin *p = plugin_list; p != NULL; p = p->next){
1308
ret = kill(p->pid, SIGTERM);
1309
if(ret == -1 and errno != ESRCH){
1310
/* Set-uid proccesses might not get closed */
1311
error(0, errno, "kill");
1316
/* Wait for any remaining child processes to terminate */
1320
if(errno != ECHILD){
1321
error(0, errno, "wait");
1327
free(pluginhelperdir);