1
/* -*- coding: utf-8 -*- */
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/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
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3
* 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 © 2008-2021 Teddy Hogeborn
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* Copyright © 2008-2021 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(), getline(),
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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() */
26
42
#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 */
32
#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(),
52
63
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
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#include <string.h> /* strsep, strlen(), asprintf() */
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#include <errno.h> /* errno */
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#include <argp.h> /* struct argp_option, struct
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argp_state, struct argp,
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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() */
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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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#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 1.0";
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const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
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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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size_t buffer_size;
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size_t buffer_length;
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volatile bool completed;
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volatile sig_atomic_t completed;
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struct plugin *next;
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static plugin *plugin_list = NULL;
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/* Gets a existing plugin based on name,
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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 exiting plugin with that name */
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for (plugin *p = plugin_list; p != NULL; p = p->next){
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if ((p->name == name)
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or (p->name and name and (strcmp(p->name, name) == 0))){
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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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132
/* 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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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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if(name != NULL){
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copy_name = strdup(name);
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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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if (new_plugin->argv == 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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free(new_plugin);
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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->environ = malloc(sizeof(char *));
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new_plugin->environ = malloc(sizeof(char *));
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} while(new_plugin->environ == NULL and errno == EINTR);
137
174
if(new_plugin->environ == NULL){
139
177
free(new_plugin->argv);
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178
free(new_plugin);
143
182
new_plugin->environ[0] = NULL;
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240
/* Add to a plugin's environment */
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static bool add_environment(plugin *p, const char *def){
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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){
186
246
/* namelen = length of name of environment variable */
187
247
size_t namelen = (size_t)(strchrnul(def, '=') - def);
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248
/* Search for this environment variable */
189
for(char **e = p->environ; *e != NULL; e++){
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if(strncmp(*e, def, namelen+1) == 0){
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/* Refuse to add an existing 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);
256
} while(new_envdef == NULL and errno == EINTR);
257
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));
199
271
* Based on the example in the GNU LibC manual chapter 13.13 "File
200
272
* Descriptor Flags".
201
* *Note File Descriptor Flags:(libc)Descriptor Flags.
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| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
203
static int set_cloexec_flag(int fd)
205
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));
206
278
/* If reading the flags failed, return error indication now. */
210
282
/* Store modified flag word in the descriptor. */
211
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
283
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
286
#endif /* not O_CLOEXEC */
215
289
/* Mark processes as completed when they exit, and save their exit
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void handle_sigchld(__attribute__((unused)) int sig){
291
static void handle_sigchld(__attribute__((unused)) int sig){
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int old_errno = errno;
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294
plugin *proc = plugin_list;
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.doc = "Group ID the plugins will run as", .group = 3 },
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443
{ .name = "debug", .key = 132,
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.doc = "Debug mode", .group = 4 },
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{ .name = "plugin-helper-dir", .key = 133,
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.doc = "Specify a different plugin helper directory",
450
* These reproduce what we would get without ARGP_NO_HELP
452
{ .name = "help", .key = '?',
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.doc = "Give this help list", .group = -1 },
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{ .name = "usage", .key = -3,
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.doc = "Give a short usage message", .group = -1 },
456
{ .name = "version", .key = 'V',
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.doc = "Print program version", .group = -1 },
368
error_t parse_opt (int key, char *arg, __attribute__((unused))
369
struct argp_state *state) {
370
/* Get the INPUT argument from `argp_parse', which we know is a
371
pointer to our plugin list pointer. */
461
__attribute__((nonnull(3)))
462
error_t parse_opt(int key, char *arg, struct argp_state *state){
373
467
case 'g': /* --global-options */
376
while((p = strsep(&arg, ",")) != NULL){
380
if(not add_argument(getplugin(NULL), p)){
381
perror("add_argument");
382
return ARGP_ERR_UNKNOWN;
387
case 'e': /* --global-env */
392
char *envdef = strdup(arg);
396
if(not add_environment(getplugin(NULL), envdef)){
397
perror("add_environment");
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)){
401
483
case 'o': /* --options-for */
403
char *p_name = strsep(&arg, ":");
404
if(p_name[0] == '\0'){
407
char *opt = strsep(&arg, ":");
413
while((p = strsep(&opt, ",")) != NULL){
417
if(not add_argument(getplugin(p_name), p)){
418
perror("add_argument");
419
return ARGP_ERR_UNKNOWN;
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)){
425
case 'f': /* --env-for */
507
case 'E': /* --env-for */
430
509
char *envdef = strchr(arg, ':');
431
510
if(envdef == NULL){
434
char *p_name = strndup(arg, (size_t) (envdef-arg));
511
argp_error(state, "No colon in \"%s\"", arg);
439
if(not add_environment(getplugin(p_name), envdef)){
440
perror("add_environment");
518
argp_error(state, "Empty plugin name");
522
if(add_environment(getplugin(arg), envdef, true)){
444
527
case 'd': /* --disable */
446
plugin *p = getplugin(arg);
448
return ARGP_ERR_UNKNOWN;
529
plugin *p = getplugin(arg);
536
case 'e': /* --enable */
538
plugin *p = getplugin(arg);
453
545
case 128: /* --plugin-dir */
454
547
plugindir = strdup(arg);
455
if(plugindir == NULL){
459
case 129: /* --config-file */
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 */
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 */
460
642
argfile = strdup(arg);
465
647
case 130: /* --userid */
466
uid = (uid_t)strtol(arg, NULL, 10);
468
648
case 131: /* --groupid */
469
gid = (gid_t)strtol(arg, NULL, 10);
471
649
case 132: /* --debug */
650
case 133: /* --plugin-helper-dir */
651
case '?': /* --help */
652
case -3: /* --usage */
653
case 'V': /* --version */
474
654
case ARGP_KEY_ARG:
475
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
480
657
return ARGP_ERR_UNKNOWN;
485
struct argp argp = { .options = options, .parser = parse_opt,
486
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
662
struct argp argp = { .options = options,
663
.parser = parse_opt_config_file,
487
665
.doc = "Mandos plugin runner -- Run plugins" };
489
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
490
if (ret == ARGP_ERR_UNKNOWN){
491
fprintf(stderr, "Unknown error while parsing arguments\n");
492
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;
496
/* Opens the configfile if aviable */
497
if (argfile == NULL){
686
/* Reset to the normal argument parser */
687
argp.parser = parse_opt;
689
/* Open the configfile if available */
498
691
conffp = fopen(AFILE, "r");
500
693
conffp = fopen(argfile, "r");
502
695
if(conffp != NULL){
503
696
char *org_line = NULL;
504
697
char *p, *arg, *new_arg, *line;
507
699
const char whitespace_delims[] = " \r\t\f\v\n";
508
700
const char comment_delim[] = "#";
511
703
custom_argv = malloc(sizeof(char*) * 2);
512
704
if(custom_argv == NULL){
514
exitstatus = EXIT_FAILURE;
705
error(0, errno, "malloc");
706
exitstatus = EX_OSERR;
517
709
custom_argv[0] = argv[0];
518
710
custom_argv[1] = NULL;
520
712
/* for each line in the config file, strip whitespace and ignore
521
713
commented text */
534
726
new_arg = strdup(p);
535
727
if(new_arg == NULL){
537
exitstatus = EXIT_FAILURE;
728
error(0, errno, "strdup");
729
exitstatus = EX_OSERR;
542
734
custom_argc += 1;
543
custom_argv = realloc(custom_argv, sizeof(char *)
544
* ((unsigned int) custom_argc + 1));
545
if(custom_argv == NULL){
547
exitstatus = EXIT_FAILURE;
736
#if defined(__GLIBC_PREREQ) and __GLIBC_PREREQ(2, 26)
737
char **new_argv = reallocarray(custom_argv, (size_t)custom_argc + 1,
740
char **new_argv = NULL;
741
if(((size_t)custom_argc + 1) > (SIZE_MAX / sizeof(char *))){
745
new_argv = realloc(custom_argv, ((size_t)custom_argc + 1)
749
if(new_argv == NULL){
750
error(0, errno, "reallocarray");
751
exitstatus = EX_OSERR;
756
custom_argv = new_argv;
551
759
custom_argv[custom_argc-1] = new_arg;
552
custom_argv[custom_argc] = NULL;
760
custom_argv[custom_argc] = NULL;
764
ret = fclose(conffp);
765
} while(ret == EOF and errno == EINTR);
767
error(0, errno, "fclose");
768
exitstatus = EX_IOERR;
557
773
/* Check for harmful errors and go to fallback. Other errors might
558
774
not affect opening plugins */
559
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
561
exitstatus = EXIT_FAILURE;
775
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
776
error(0, errno, "fopen");
777
exitstatus = EX_OSERR;
565
/* If there was any arguments from configuration file,
566
pass them to parser as command arguments */
781
/* If there were any arguments from the configuration file, pass
782
them to parser as command line arguments */
567
783
if(custom_argv != NULL){
568
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, NULL);
569
if (ret == ARGP_ERR_UNKNOWN){
570
fprintf(stderr, "Unknown error while parsing arguments\n");
571
exitstatus = EXIT_FAILURE;
784
ret = argp_parse(&argp, custom_argc, custom_argv,
785
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
793
error(0, errno, "argp_parse");
794
exitstatus = EX_OSERR;
797
exitstatus = EX_CONFIG;
802
/* Parse actual command line arguments, to let them override the
804
ret = argp_parse(&argp, argc, argv,
805
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
813
error(0, errno, "argp_parse");
814
exitstatus = EX_OSERR;
817
exitstatus = EX_USAGE;
822
char *pluginhelperenv;
824
ret = asprintf(&pluginhelperenv, "MANDOSPLUGINHELPERDIR=%s",
825
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
827
bret = add_environment(getplugin(NULL), pluginhelperenv, true);
829
if(ret == -1 or not bret){
830
error(0, errno, "Failed to set MANDOSPLUGINHELPERDIR"
831
" environment variable to \"%s\" for all plugins\n",
832
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
835
free(pluginhelperenv);
577
for(plugin *p = plugin_list; p != NULL; p=p->next){
840
for(plugin *p = plugin_list; p != NULL; p = p->next){
578
841
fprintf(stderr, "Plugin: %s has %d arguments\n",
579
842
p->name ? p->name : "Global", p->argc - 1);
580
843
for(char **a = p->argv; *a != NULL; a++){
581
844
fprintf(stderr, "\tArg: %s\n", *a);
583
fprintf(stderr, "...and %u environment variables\n", p->envc);
846
fprintf(stderr, "...and %d environment variables\n", p->envc);
584
847
for(char **a = p->environ; *a != NULL; a++){
585
848
fprintf(stderr, "\t%s\n", *a);
854
/* Work around Debian bug #633582:
855
<https://bugs.debian.org/633582> */
856
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
857
if(plugindir_fd == -1){
859
error(0, errno, "open(\"" PDIR "\")");
862
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
864
error(0, errno, "fstat");
866
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
867
ret = fchown(plugindir_fd, uid, gid);
869
error(0, errno, "fchown");
590
/* Strip permissions down to nobody */
876
/* Work around Debian bug #981302
877
<https://bugs.debian.org/981302> */
878
if(lstat("/dev/fd", &st) != 0 and errno == ENOENT){
879
ret = symlink("/proc/self/fd", "/dev/fd");
881
error(0, errno, "Failed to create /dev/fd symlink");
886
/* Lower permissions */
889
error(0, errno, "setgid");
591
891
ret = setuid(uid);
600
if (plugindir == NULL){
603
dir = opendir(plugindir);
607
perror("Could not open plugin dir");
608
exitstatus = EXIT_FAILURE;
612
/* Set the FD_CLOEXEC flag on the directory, if possible */
893
error(0, errno, "setuid");
896
/* Open plugin directory with close_on_exec flag */
614
int dir_fd = dirfd(dir);
616
ret = set_cloexec_flag(dir_fd);
618
perror("set_cloexec_flag");
619
exitstatus = EXIT_FAILURE;
898
dir_fd = open(plugindir != NULL ? plugindir : PDIR, O_RDONLY |
901
#else /* not O_CLOEXEC */
903
#endif /* not O_CLOEXEC */
906
error(0, errno, "Could not open plugin dir");
907
exitstatus = EX_UNAVAILABLE;
912
/* Set the FD_CLOEXEC flag on the directory */
913
ret = set_cloexec_flag(dir_fd);
915
error(0, errno, "set_cloexec_flag");
916
exitstatus = EX_OSERR;
919
#endif /* O_CLOEXEC */
922
int good_name(const struct dirent * const dirent){
923
const char * const patterns[] = { ".*", "#*#", "*~", "*.dpkg-new",
924
"*.dpkg-old", "*.dpkg-bak",
925
"*.dpkg-divert", NULL };
927
#pragma GCC diagnostic push
928
#pragma GCC diagnostic ignored "-Wcast-qual"
930
for(const char **pat = (const char **)patterns;
931
*pat != NULL; pat++){
933
#pragma GCC diagnostic pop
935
if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
938
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
939
" matching pattern %s\n", dirent->d_name, *pat);
947
int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
949
if(numplugins == -1){
950
error(0, errno, "Could not scan plugin dir");
952
exitstatus = EX_OSERR;
625
956
FD_ZERO(&rfds_all);
627
958
/* Read and execute any executable in the plugin directory*/
629
dirst = readdir(dir);
631
// All directory entries have been processed
635
exitstatus = EXIT_FAILURE;
641
d_name_len = strlen(dirst->d_name);
643
// Ignore dotfiles, backup files and other junk
645
bool bad_name = false;
647
const char const *bad_prefixes[] = { ".", "#", NULL };
649
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
651
".dpkg-divert", NULL };
652
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
653
size_t pre_len = strlen(*pre);
654
if((d_name_len >= pre_len)
655
and strncmp((dirst->d_name), *pre, pre_len) == 0){
657
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
658
" with bad prefix %s\n", dirst->d_name, *pre);
667
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
668
size_t suf_len = strlen(*suf);
669
if((d_name_len >= suf_len)
670
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
673
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
674
" with bad suffix %s\n", dirst->d_name, *suf);
687
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
693
ret = stat(filename, &st);
959
for(int i = 0; i < numplugins; i++){
961
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
963
error(0, errno, "Could not open plugin");
967
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
969
error(0, errno, "stat");
700
975
/* Ignore non-executable files */
701
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
976
if(not S_ISREG(st.st_mode)
977
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
703
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
704
" with bad type or mode\n", filename);
980
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
981
" with bad type or mode\n",
982
plugindir != NULL ? plugindir : PDIR,
983
direntries[i]->d_name);
710
plugin *p = getplugin(dirst->d_name);
990
plugin *p = getplugin(direntries[i]->d_name);
992
error(0, errno, "getplugin");
718
999
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
1000
direntries[i]->d_name);
1003
free(direntries[i]);
728
1010
for(char **a = g->argv + 1; *a != NULL; a++){
729
1011
if(not add_argument(p, *a)){
730
perror("add_argument");
1012
error(0, errno, "add_argument");
733
1015
/* Add global environment variables */
734
1016
for(char **e = g->environ; *e != NULL; e++){
735
if(not add_environment(p, *e)){
736
perror("add_environment");
1017
if(not add_environment(p, *e, false)){
1018
error(0, errno, "add_environment");
741
/* If this plugin has any environment variables, we will call
742
using execve and need to duplicate the environment from this
1023
/* If this plugin has any environment variables, we need to
1024
duplicate the environment from this process, too. */
744
1025
if(p->environ[0] != NULL){
745
1026
for(char **e = environ; *e != NULL; e++){
746
char *copy = strdup(*e);
751
if(not add_environment(p, copy)){
752
perror("add_environment");
1027
if(not add_environment(p, *e, false)){
1028
error(0, errno, "add_environment");
761
exitstatus = EXIT_FAILURE;
1035
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
1036
#else /* O_CLOEXEC */
1037
ret = (int)TEMP_FAILURE_RETRY(pipe2(pipefd, O_CLOEXEC));
1038
#endif /* O_CLOEXEC */
1040
error(0, errno, "pipe");
1041
exitstatus = EX_OSERR;
1042
free(direntries[i]);
1045
if(pipefd[0] >= FD_SETSIZE){
1046
fprintf(stderr, "pipe()[0] (%d) >= FD_SETSIZE (%d)", pipefd[0],
1050
exitstatus = EX_OSERR;
1051
free(direntries[i]);
764
1055
/* Ask OS to automatic close the pipe on exec */
765
1056
ret = set_cloexec_flag(pipefd[0]);
767
perror("set_cloexec_flag");
768
exitstatus = EXIT_FAILURE;
1058
error(0, errno, "set_cloexec_flag");
1061
exitstatus = EX_OSERR;
1062
free(direntries[i]);
771
1065
ret = set_cloexec_flag(pipefd[1]);
773
perror("set_cloexec_flag");
774
exitstatus = EXIT_FAILURE;
1067
error(0, errno, "set_cloexec_flag");
1070
exitstatus = EX_OSERR;
1071
free(direntries[i]);
1074
#endif /* not O_CLOEXEC */
777
1075
/* Block SIGCHLD until process is safely in process list */
778
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
1076
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1077
&sigchld_action.sa_mask,
780
perror("sigprocmask");
781
exitstatus = EXIT_FAILURE;
1080
error(0, errno, "sigprocmask");
1081
exitstatus = EX_OSERR;
1082
free(direntries[i]);
784
// Starting a new process to be watched
1085
/* Starting a new process to be watched */
1089
} while(pid == -1 and errno == EINTR);
788
exitstatus = EXIT_FAILURE;
1091
error(0, errno, "fork");
1092
TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1093
&sigchld_action.sa_mask, NULL));
1096
exitstatus = EX_OSERR;
1097
free(direntries[i]);
792
1101
/* this is the child process */
793
1102
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1104
error(0, errno, "sigaction");
798
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1107
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
800
perror("sigprocmask");
1109
error(0, errno, "sigprocmask");
804
1113
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1115
error(0, errno, "dup2");
811
/* If dir has no file descriptor, we could not set FD_CLOEXEC
812
above and must now close it manually here. */
815
if(p->environ[0] == NULL){
816
if(execv(filename, p->argv) < 0){
821
if(execve(filename, p->argv, p->environ) < 0){
1119
if(fexecve(plugin_fd, p->argv,
1120
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1121
error(0, errno, "fexecve for %s/%s",
1122
plugindir != NULL ? plugindir : PDIR,
1123
direntries[i]->d_name);
828
1128
/* Parent process */
829
1129
close(pipefd[1]); /* Close unused write end of pipe */
831
plugin *new_plugin = getplugin(dirst->d_name);
832
if (new_plugin == NULL){
834
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1131
plugin *new_plugin = getplugin(direntries[i]->d_name);
1132
if(new_plugin == NULL){
1133
error(0, errno, "getplugin");
1134
ret = (int)(TEMP_FAILURE_RETRY
1135
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
836
perror("sigprocmask");
1138
error(0, errno, "sigprocmask");
838
exitstatus = EXIT_FAILURE;
1140
exitstatus = EX_OSERR;
1141
free(direntries[i]);
1144
free(direntries[i]);
842
1146
new_plugin->pid = pid;
843
1147
new_plugin->fd = pipefd[0];
1150
fprintf(stderr, "Plugin %s started (PID %" PRIdMAX ")\n",
1151
new_plugin->name, (intmax_t) (new_plugin->pid));
845
1154
/* Unblock SIGCHLD so signal handler can be run if this process
846
1155
has already completed */
847
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1156
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1157
&sigchld_action.sa_mask,
849
perror("sigprocmask");
850
exitstatus = EXIT_FAILURE;
1160
error(0, errno, "sigprocmask");
1161
exitstatus = EX_OSERR;
854
1165
FD_SET(new_plugin->fd, &rfds_all);
856
if (maxfd < new_plugin->fd){
1167
if(maxfd < new_plugin->fd){
857
1168
maxfd = new_plugin->fd;
1176
free_plugin(getplugin(NULL));
865
1178
for(plugin *p = plugin_list; p != NULL; p = p->next){
866
1179
if(p->pid != 0){
872
1185
free_plugin_list();
876
1189
/* Main loop while running plugins exist */
877
1190
while(plugin_list){
878
1191
fd_set rfds = rfds_all;
879
1192
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
880
if (select_ret == -1){
882
exitstatus = EXIT_FAILURE;
1193
if(select_ret == -1 and errno != EINTR){
1194
error(0, errno, "select");
1195
exitstatus = EX_OSERR;
885
1198
/* OK, now either a process completed, or something can be read
886
1199
from one of them */
887
for(plugin *proc = plugin_list; proc != NULL; proc = proc->next){
1200
for(plugin *proc = plugin_list; proc != NULL;){
888
1201
/* Is this process completely done? */
889
if(proc->eof and proc->completed){
1202
if(proc->completed and proc->eof){
890
1203
/* Only accept the plugin output if it exited cleanly */
891
1204
if(not WIFEXITED(proc->status)
892
1205
or WEXITSTATUS(proc->status) != 0){
893
1206
/* Bad exit by plugin */
896
1209
if(WIFEXITED(proc->status)){
897
fprintf(stderr, "Plugin %u exited with status %d\n",
898
(unsigned int) (proc->pid),
1210
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1211
" status %d\n", proc->name,
1212
(intmax_t) (proc->pid),
899
1213
WEXITSTATUS(proc->status));
900
} else if(WIFSIGNALED(proc->status)) {
901
fprintf(stderr, "Plugin %u killed by signal %d\n",
902
(unsigned int) (proc->pid),
903
WTERMSIG(proc->status));
904
} else if(WCOREDUMP(proc->status)){
905
fprintf(stderr, "Plugin %d dumped core\n",
906
(unsigned int) (proc->pid));
1214
} else if(WIFSIGNALED(proc->status)){
1215
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1216
" signal %d: %s\n", proc->name,
1217
(intmax_t) (proc->pid),
1218
WTERMSIG(proc->status),
1219
strsignal(WTERMSIG(proc->status)));
910
1223
/* Remove the plugin */
911
1224
FD_CLR(proc->fd, &rfds_all);
913
1226
/* Block signal while modifying process_list */
914
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
1227
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1229
&sigchld_action.sa_mask,
916
perror("sigprocmask");
917
exitstatus = EXIT_FAILURE;
1232
error(0, errno, "sigprocmask");
1233
exitstatus = EX_OSERR;
1237
plugin *next_plugin = proc->next;
920
1238
free_plugin(proc);
921
1241
/* We are done modifying process list, so unblock signal */
922
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
1242
ret = (int)(TEMP_FAILURE_RETRY
1243
(sigprocmask(SIG_UNBLOCK,
1244
&sigchld_action.sa_mask, NULL)));
925
perror("sigprocmask");
926
exitstatus = EXIT_FAILURE;
1246
error(0, errno, "sigprocmask");
1247
exitstatus = EX_OSERR;
930
1251
if(plugin_list == NULL){
936
1258
/* This process exited nicely, so print its buffer */
938
1260
bool bret = print_out_password(proc->buffer,
939
1261
proc->buffer_length);
941
perror("print_out_password");
942
exitstatus = EXIT_FAILURE;
1263
error(0, errno, "print_out_password");
1264
exitstatus = EX_IOERR;
947
1269
/* This process has not completed. Does it have any output? */
948
1270
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
949
1271
/* This process had nothing to say at this time */
952
1275
/* Before reading, make the process' data buffer large enough */
953
1276
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
954
proc->buffer = realloc(proc->buffer, proc->buffer_size
955
+ (size_t) BUFFER_SIZE);
956
if (proc->buffer == NULL){
958
exitstatus = EXIT_FAILURE;
1277
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1278
+ (size_t) BUFFER_SIZE);
1279
if(new_buffer == NULL){
1280
error(0, errno, "malloc");
1281
exitstatus = EX_OSERR;
1284
proc->buffer = new_buffer;
961
1285
proc->buffer_size += BUFFER_SIZE;
963
1287
/* Read from the process */
964
ret = read(proc->fd, proc->buffer + proc->buffer_length,
1288
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1290
+ proc->buffer_length,
967
1293
/* Read error from this process; ignore the error */
972
1299
proc->eof = true;
974
proc->buffer_length += (size_t) ret;
1301
proc->buffer_length += (size_t) sret;
982
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1309
if(plugin_list == NULL or (exitstatus != EXIT_SUCCESS
1310
and exitstatus != EX_OK)){
983
1311
/* Fallback if all plugins failed, none are found or an error
986
1314
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
987
1315
char *passwordbuffer = getpass("Password: ");
988
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
1316
size_t len = strlen(passwordbuffer);
1317
/* Strip trailing newline */
1318
if(len > 0 and passwordbuffer[len-1] == '\n'){
1319
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1322
bret = print_out_password(passwordbuffer, len);
990
perror("print_out_password");
991
exitstatus = EXIT_FAILURE;
1324
error(0, errno, "print_out_password");
1325
exitstatus = EX_IOERR;
995
1329
/* Restore old signal handler */
996
1330
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
999
exitstatus = EXIT_FAILURE;
1332
error(0, errno, "sigaction");
1333
exitstatus = EX_OSERR;
1002
1336
if(custom_argv != NULL){
1003
1337
for(char **arg = custom_argv+1; *arg != NULL; arg++){