/mandos/trunk : revision 133

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

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

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/*

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* Mandos plugin runner - Run Mandos plugins

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*

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*

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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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*/

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#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),

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asprintf(), O_CLOEXEC */

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asprintf() */

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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, fileno(), fprintf(),

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stderr, STDOUT_FILENO */

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#include <sys/types.h> /* DIR, fdopendir(), stat(), struct

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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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WEXITSTATUS(), WTERMSIG(),

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WCOREDUMP() */

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WEXITSTATUS() */

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

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

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

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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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dup2, STDOUT_FILENO, _exit(),

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execv(), write(), read(),

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close() */

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

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FD_CLOEXEC */

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

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strsignal() */

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

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

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

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argp_state, struct argp,

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

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sigaddset(), sigaction(),

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sigprocmask(), SIG_BLOCK, SIGCHLD,

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SIG_UNBLOCK, kill(), sig_atomic_t

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*/

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SIG_UNBLOCK, kill() */

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

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

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#define BUFFER_SIZE 256

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#define PDIR "/lib/mandos/plugins.d"

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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_version = "plugin-runner 1.0";

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const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";

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struct plugin;

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typedef struct plugin{

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char *name; /* can be NULL or any plugin name */

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char **argv;

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char **environ;

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int envc;

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bool disabled;

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/* Variables used for running processes*/

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pid_t pid;

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int fd;

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size_t buffer_size;

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size_t buffer_length;

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bool eof;

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volatile sig_atomic_t completed;

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int status;

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volatile bool completed;

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volatile int status;

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struct plugin *next;

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} plugin;

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static plugin *plugin_list = NULL;

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/* Gets an existing plugin based on name,

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/* Gets a existing plugin based on name,

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or if none is found, creates a new one */

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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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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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return p;

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}

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}

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/* Create a new plugin */

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plugin *new_plugin = NULL;

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do {

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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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plugin *new_plugin = malloc(sizeof(plugin));

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if (new_plugin == NULL){

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return NULL;

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}

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char *copy_name = NULL;

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if(name != NULL){

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do {

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copy_name = strdup(name);

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} while(copy_name == NULL and errno == EINTR);

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copy_name = strdup(name);

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if(copy_name == NULL){

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free(new_plugin);

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return NULL;

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}

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}

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

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.argc = 1,

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.disabled = false,

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.next = plugin_list };

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do {

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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 = (plugin) { .name = copy_name,

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.argc = 1,

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.disabled = false,

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.next = plugin_list };

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

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if (new_plugin->argv == NULL){

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free(copy_name);

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free(new_plugin);

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return NULL;

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}

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new_plugin->argv[0] = copy_name;

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new_plugin->argv[1] = NULL;

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do {

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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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new_plugin->environ = malloc(sizeof(char *));

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if(new_plugin->environ == NULL){

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free(copy_name);

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free(new_plugin->argv);

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return NULL;

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}

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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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return new_plugin;

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static bool add_to_char_array(const char *new, char ***array,

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int *len){

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/* Resize the pointed-to array to hold one more pointer */

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do {

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*array = realloc(*array, sizeof(char *)

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* (size_t) ((*len) + 2));

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} while(*array == NULL and errno == EINTR);

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*array = realloc(*array, sizeof(char *)

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* (size_t) ((*len) + 2));

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/* Malloc check */

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if(*array == NULL){

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return false;

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}

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/* Make a copy of the new string */

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char *copy;

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do {

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copy = strdup(new);

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} while(copy == NULL and errno == EINTR);

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char *copy = strdup(new);

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if(copy == NULL){

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return false;

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}

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}

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/* Add to a plugin's environment */

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static bool add_environment(plugin *p, const char *def, bool replace){

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static bool add_environment(plugin *p, const char *def){

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if(p == NULL){

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return false;

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}

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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 **e = p->environ; *e != NULL; e++){

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if(strncmp(*e, def, namelen + 1) == 0){

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/* It already exists */

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if(replace){

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char *new;

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do {

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new = realloc(*e, strlen(def) + 1);

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} while(new == NULL and errno == EINTR);

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if(new == NULL){

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return false;

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}

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*e = new;

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strcpy(*e, def);

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}

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return true;

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}

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}

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return add_to_char_array(def, &(p->environ), &(p->envc));

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}

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/*

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

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* Descriptor Flags".

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

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

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*/

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static int set_cloexec_flag(int fd){

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

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static int set_cloexec_flag(int fd)

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{

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

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/* If reading the flags failed, return error indication now. */

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if(ret < 0){

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return ret;

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}

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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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ret | FD_CLOEXEC));

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return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);

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}

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

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status. */

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

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int old_errno = errno;

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

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while(true){

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plugin *proc = plugin_list;

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int status;

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break;

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}

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if(pid == -1){

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if(errno == ECHILD){

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/* No child processes */

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break;

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if (errno != ECHILD){

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perror("waitpid");

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}

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perror("waitpid");

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/* No child processes */

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break;

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}

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

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while(proc != NULL and proc->pid != pid){

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proc = proc->next;

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continue;

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}

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proc->status = status;

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proc->completed = 1;

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proc->completed = true;

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}

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errno = old_errno;

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}

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/* Prints out a password to stdout */

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static bool print_out_password(const char *buffer, size_t length){

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bool print_out_password(const char *buffer, size_t length){

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ssize_t ret;

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if(length>0 and buffer[length-1] == '\n'){

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length--;

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}

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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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length - written));

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}

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free(plugin_node->environ);

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free(plugin_node->buffer);

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

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if(plugin_node == plugin_list){

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/* First one - simple */

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struct stat st;

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fd_set rfds_all;

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int ret, maxfd = 0;

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ssize_t sret;

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uid_t uid = 65534;

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gid_t gid = 65534;

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bool debug = false;

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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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{ .name = "global-envs", .key = 'e',

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.arg = "VAR=value",

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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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{ .name = "envs-for", .key = 'f',

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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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.arg = "PLUGIN",

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.doc = "Disable a specific plugin", .group = 1 },

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{ .name = "enable", .key = 'e',

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.arg = "PLUGIN",

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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 = NULL }

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};

399

358

400

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

401

struct argp_state *state){

402

switch(key){

403

char *tmp;

404

intmax_t tmpmax;

359

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

360

struct argp_state *state) {

361

/* Get the INPUT argument from `argp_parse', which we know is a

362

pointer to our plugin list pointer. */

363

switch (key) {

405

364

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

406

if(arg != NULL){

407

char *plugin_option;

408

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

409

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

365

if (arg != NULL){

366

char *p;

367

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

368

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

410

369

continue;

411

370

}

412

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

371

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

413

372

perror("add_argument");

414

373

return ARGP_ERR_UNKNOWN;

415

374

}

416

375

}

417

376

}

418

377

break;

419

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

378

case 'e': /* --global-envs */

420

379

if(arg == NULL){

421

380

break;

422

381

}

423

if(not add_environment(getplugin(NULL), arg, true)){

424

perror("add_environment");

382

{

383

char *envdef = strdup(arg);

384

if(envdef == NULL){

385

break;

386

}

387

if(not add_environment(getplugin(NULL), envdef)){

388

perror("add_environment");

389

}

425

390

}

426

391

break;

427

392

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

428

if(arg != NULL){

429

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

430

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

431

break;

432

}

433

char *plugin_option;

434

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

435

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

436

perror("add_argument");

437

return ARGP_ERR_UNKNOWN;

393

if (arg != NULL){

394

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

395

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

396

break;

397

}

398

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

399

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

400

break;

401

}

402

if(opt != NULL){

403

char *p;

404

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

405

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

406

continue;

407

}

408

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

409

perror("add_argument");

410

return ARGP_ERR_UNKNOWN;

411

}

438

412

}

439

413

}

440

414

}

441

415

break;

442

case 'E': /* --env-for */

416

case 'f': /* --envs-for */

443

417

if(arg == NULL){

444

418

break;

445

419

}

448

422

if(envdef == NULL){

449

423

break;

450

424

}

451

*envdef = '\0';

452

if(not add_environment(getplugin(arg), envdef+1, true)){

425

char *p_name = strndup(arg, (size_t) (envdef-arg));

426

if(p_name == NULL){

427

break;

428

}

429

envdef++;

430

if(not add_environment(getplugin(p_name), envdef)){

453

431

perror("add_environment");

454

432

}

455

433

}

456

434

break;

457

435

case 'd': /* --disable */

458

if(arg != NULL){

436

if (arg != NULL){

459

437

plugin *p = getplugin(arg);

460

438

if(p == NULL){

461

439

return ARGP_ERR_UNKNOWN;

463

441

p->disabled = true;

464

442

}

465

443

break;

466

case 'e': /* --enable */

467

if(arg != NULL){

468

plugin *p = getplugin(arg);

469

if(p == NULL){

470

return ARGP_ERR_UNKNOWN;

471

}

472

p->disabled = false;

473

}

474

break;

475

444

case 128: /* --plugin-dir */

476

free(plugindir);

477

445

plugindir = strdup(arg);

478

446

if(plugindir == NULL){

479

447

perror("strdup");

480

}

481

break;

482

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

483

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

484

break;

485

case 130: /* --userid */

486

errno = 0;

487

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

488

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

489

or tmpmax != (uid_t)tmpmax){

490

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

491

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

492

} else {

493

uid = (uid_t)tmpmax;

494

}

495

break;

496

case 131: /* --groupid */

497

errno = 0;

498

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

499

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

500

or tmpmax != (gid_t)tmpmax){

501

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

502

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

503

} else {

504

gid = (gid_t)tmpmax;

505

}

506

break;

507

case 132: /* --debug */

508

debug = true;

509

break;

510

/*

511

* When adding more options before this line, remember to also add a

512

* "case" to the "parse_opt_config_file" function below.

513

*/

514

case ARGP_KEY_ARG:

515

/* Cryptsetup always passes an argument, which is an empty

516

string if "none" was specified in /etc/crypttab. So if

517

argument was empty, we ignore it silently. */

518

if(arg[0] != '\0'){

519

fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);

520

}

521

break;

522

case ARGP_KEY_END:

523

break;

524

default:

525

return ARGP_ERR_UNKNOWN;

526

}

527

return 0;

528

}

529

530

/* This option parser is the same as parse_opt() above, except it

531

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

532

error_t parse_opt_config_file(int key, char *arg,

533

__attribute__((unused))

534

struct argp_state *state){

535

switch(key){

536

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

537

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

538

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

539

case 'E': /* --env-for */

540

case 'd': /* --disable */

541

case 'e': /* --enable */

542

case 128: /* --plugin-dir */

543

break;

544

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

545

free(argfile);

448

}

449

break;

450

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

546

451

argfile = strdup(arg);

547

452

if(argfile == NULL){

548

453

perror("strdup");

549

454

}

550

break;

455

break;

551

456

case 130: /* --userid */

457

uid = (uid_t)strtol(arg, NULL, 10);

458

break;

552

459

case 131: /* --groupid */

460

gid = (gid_t)strtol(arg, NULL, 10);

461

break;

553

462

case 132: /* --debug */

463

debug = true;

464

break;

554

465

case ARGP_KEY_ARG:

466

fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);

467

break;

555

468

case ARGP_KEY_END:

556

469

break;

557

470

default:

560

473

return 0;

561

474

}

562

475

563

struct argp argp = { .options = options,

564

.parser = parse_opt_config_file,

565

.args_doc = "",

476

struct argp argp = { .options = options, .parser = parse_opt,

477

.args_doc = "[+PLUS_SEPARATED_OPTIONS]",

566

478

.doc = "Mandos plugin runner -- Run plugins" };

567

479

568

/* Parse using parse_opt_config_file() in order to get the custom

569

config file location, if any. */

570

ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);

571

if(ret == ARGP_ERR_UNKNOWN){

480

ret = argp_parse (&argp, argc, argv, 0, 0, NULL);

481

if (ret == ARGP_ERR_UNKNOWN){

572

482

fprintf(stderr, "Unknown error while parsing arguments\n");

573

483

exitstatus = EXIT_FAILURE;

574

484

goto fallback;

575

485

}

576

577

/* Reset to the normal argument parser */

578

argp.parser = parse_opt;

579

580

/* Open the configfile if available */

581

if(argfile == NULL){

486

487

/* Opens the configfile if aviable */

488

if (argfile == NULL){

582

489

conffp = fopen(AFILE, "r");

583

490

} else {

584

491

conffp = fopen(argfile, "r");

585

}

492

}

586

493

if(conffp != NULL){

587

494

char *org_line = NULL;

588

495

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

589

496

size_t size = 0;

497

ssize_t sret;

590

498

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

591

499

const char comment_delim[] = "#";

592

500

593

501

custom_argc = 1;

594

502

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

595

503

if(custom_argv == NULL){

599

507

}

600

508

custom_argv[0] = argv[0];

601

509

custom_argv[1] = NULL;

602

510

603

511

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

604

512

commented text */

605

513

while(true){

607

515

if(sret == -1){

608

516

break;

609

517

}

610

518

611

519

line = org_line;

612

520

arg = strsep(&line, comment_delim);

613

521

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

632

540

goto fallback;

633

541

}

634

542

custom_argv[custom_argc-1] = new_arg;

635

custom_argv[custom_argc] = NULL;

543

custom_argv[custom_argc] = NULL;

636

544

}

637

545

}

638

do {

639

ret = fclose(conffp);

640

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

641

if(ret == EOF){

642

perror("fclose");

643

exitstatus = EXIT_FAILURE;

644

goto fallback;

645

}

646

546

free(org_line);

647

} else {

547

} else{

648

548

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

649

549

not affect opening plugins */

650

if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){

550

if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){

651

551

perror("fopen");

652

552

exitstatus = EXIT_FAILURE;

653

553

goto fallback;

656

556

/* If there was any arguments from configuration file,

657

557

pass them to parser as command arguments */

658

558

if(custom_argv != NULL){

659

ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,

660

0, NULL);

661

if(ret == ARGP_ERR_UNKNOWN){

559

ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, NULL);

560

if (ret == ARGP_ERR_UNKNOWN){

662

561

fprintf(stderr, "Unknown error while parsing arguments\n");

663

562

exitstatus = EXIT_FAILURE;

664

563

goto fallback;

665

564

}

666

565

}

667

566

668

/* Parse actual command line arguments, to let them override the

669

config file */

670

ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);

671

if(ret == ARGP_ERR_UNKNOWN){

672

fprintf(stderr, "Unknown error while parsing arguments\n");

673

exitstatus = EXIT_FAILURE;

674

goto fallback;

675

}

676

677

567

if(debug){

678

568

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

679

569

fprintf(stderr, "Plugin: %s has %d arguments\n",

681

571

for(char **a = p->argv; *a != NULL; a++){

682

572

fprintf(stderr, "\tArg: %s\n", *a);

683

573

}

684

fprintf(stderr, "...and %d environment variables\n", p->envc);

574

fprintf(stderr, "...and %u environment variables\n", p->envc);

685

575

for(char **a = p->environ; *a != NULL; a++){

686

576

fprintf(stderr, "\t%s\n", *a);

687

577

}

688

578

}

689

579

}

690

580

691

581

/* Strip permissions down to nobody */

582

ret = setuid(uid);

583

if (ret == -1){

584

perror("setuid");

585

}

692

586

setgid(gid);

693

if(ret == -1){

587

if (ret == -1){

694

588

perror("setgid");

695

589

}

696

ret = setuid(uid);

697

if(ret == -1){

698

perror("setuid");

699

}

700

701

/* Open plugin directory with close_on_exec flag */

590

591

if (plugindir == NULL){

592

dir = opendir(PDIR);

593

} else {

594

dir = opendir(plugindir);

595

}

596

597

if(dir == NULL){

598

perror("Could not open plugin dir");

599

exitstatus = EXIT_FAILURE;

600

goto fallback;

601

}

602

603

/* Set the FD_CLOEXEC flag on the directory, if possible */

702

604

{

703

int dir_fd = -1;

704

if(plugindir == NULL){

705

dir_fd = open(PDIR, O_RDONLY |

706

#ifdef O_CLOEXEC

707

O_CLOEXEC

708

#else /* not O_CLOEXEC */

709

0

710

#endif /* not O_CLOEXEC */

711

);

712

} else {

713

dir_fd = open(plugindir, O_RDONLY |

714

#ifdef O_CLOEXEC

715

O_CLOEXEC

716

#else /* not O_CLOEXEC */

717

0

718

#endif /* not O_CLOEXEC */

719

);

720

}

721

if(dir_fd == -1){

722

perror("Could not open plugin dir");

723

exitstatus = EXIT_FAILURE;

724

goto fallback;

725

}

726

727

#ifndef O_CLOEXEC

728

/* Set the FD_CLOEXEC flag on the directory */

729

ret = set_cloexec_flag(dir_fd);

730

if(ret < 0){

731

perror("set_cloexec_flag");

732

TEMP_FAILURE_RETRY(close(dir_fd));

733

exitstatus = EXIT_FAILURE;

734

goto fallback;

735

}

736

#endif /* O_CLOEXEC */

737

738

dir = fdopendir(dir_fd);

739

if(dir == NULL){

740

perror("Could not open plugin dir");

741

TEMP_FAILURE_RETRY(close(dir_fd));

742

exitstatus = EXIT_FAILURE;

743

goto fallback;

605

int dir_fd = dirfd(dir);

606

if(dir_fd >= 0){

607

ret = set_cloexec_flag(dir_fd);

608

if(ret < 0){

609

perror("set_cloexec_flag");

610

exitstatus = EXIT_FAILURE;

611

goto fallback;

612

}

744

613

}

745

614

}

746

615

747

616

FD_ZERO(&rfds_all);

748

617

749

618

/* Read and execute any executable in the plugin directory*/

750

619

while(true){

751

do {

752

dirst = readdir(dir);

753

} while(dirst == NULL and errno == EINTR);

620

dirst = readdir(dir);

754

621

755

/* All directory entries have been processed */

622

// All directory entries have been processed

756

623

if(dirst == NULL){

757

if(errno == EBADF){

624

if (errno == EBADF){

758

625

perror("readdir");

759

626

exitstatus = EXIT_FAILURE;

760

627

goto fallback;

764

631

765

632

d_name_len = strlen(dirst->d_name);

766

633

767

/* Ignore dotfiles, backup files and other junk */

634

// Ignore dotfiles, backup files and other junk

768

635

{

769

636

bool bad_name = false;

770

637

772

639

773

640

const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",

774

641

".dpkg-old",

775

".dpkg-bak",

776

642

".dpkg-divert", NULL };

777

643

for(const char **pre = bad_prefixes; *pre != NULL; pre++){

778

644

size_t pre_len = strlen(*pre);

807

673

continue;

808

674

}

809

675

}

810

676

811

677

char *filename;

812

if(plugindir == NULL){

813

ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",

814

dirst->d_name));

815

} else {

816

ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",

817

plugindir,

818

dirst->d_name));

819

}

678

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

820

679

if(ret < 0){

821

680

perror("asprintf");

822

681

continue;

823

682

}

824

683

825

ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));

826

if(ret == -1){

684

ret = stat(filename, &st);

685

if (ret == -1){

827

686

perror("stat");

828

687

free(filename);

829

688

continue;

830

689

}

831

690

832

691

/* Ignore non-executable files */

833

if(not S_ISREG(st.st_mode)

834

or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){

692

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

835

693

if(debug){

836

694

fprintf(stderr, "Ignoring plugin dir entry \"%s\""

837

695

" with bad type or mode\n", filename);

865

723

}

866

724

/* Add global environment variables */

867

725

for(char **e = g->environ; *e != NULL; e++){

868

if(not add_environment(p, *e, false)){

726

if(not add_environment(p, *e)){

869

727

perror("add_environment");

870

728

}

871

729

}

876

734

process, too. */

877

735

if(p->environ[0] != NULL){

878

736

for(char **e = environ; *e != NULL; e++){

879

if(not add_environment(p, *e, false)){

737

char *copy = strdup(*e);

738

if(copy == NULL){

739

perror("strdup");

740

continue;

741

}

742

if(not add_environment(p, copy)){

880

743

perror("add_environment");

881

744

}

882

745

}

883

746

}

884

747

885

748

int pipefd[2];

886

ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));

887

if(ret == -1){

749

ret = pipe(pipefd);

750

if (ret == -1){

888

751

perror("pipe");

889

752

exitstatus = EXIT_FAILURE;

890

753

goto fallback;

903

766

goto fallback;

904

767

}

905

768

/* Block SIGCHLD until process is safely in process list */

906

ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,

907

&sigchld_action.sa_mask,

908

NULL));

769

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

909

770

if(ret < 0){

910

771

perror("sigprocmask");

911

772

exitstatus = EXIT_FAILURE;

912

773

goto fallback;

913

774

}

914

/* Starting a new process to be watched */

915

pid_t pid;

916

do {

917

pid = fork();

918

} while(pid == -1 and errno == EINTR);

775

// Starting a new process to be watched

776

pid_t pid = fork();

919

777

if(pid == -1){

920

778

perror("fork");

921

779

exitstatus = EXIT_FAILURE;

928

786

perror("sigaction");

929

787

_exit(EXIT_FAILURE);

930

788

}

931

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

789

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

932

790

if(ret < 0){

933

791

perror("sigprocmask");

934

792

_exit(EXIT_FAILURE);

935

793

}

936

794

937

795

ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */

938

796

if(ret == -1){

939

797

perror("dup2");

959

817

/* no return */

960

818

}

961

819

/* Parent process */

962

TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of

963

pipe */

820

close(pipefd[1]); /* Close unused write end of pipe */

964

821

free(filename);

965

822

plugin *new_plugin = getplugin(dirst->d_name);

966

if(new_plugin == NULL){

823

if (new_plugin == NULL){

967

824

perror("getplugin");

968

ret = (int)(TEMP_FAILURE_RETRY

969

(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,

970

NULL)));

825

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

971

826

if(ret < 0){

972

827

perror("sigprocmask");

973

828

}

980

835

981

836

/* Unblock SIGCHLD so signal handler can be run if this process

982

837

has already completed */

983

ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,

984

&sigchld_action.sa_mask,

985

NULL));

838

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

986

839

if(ret < 0){

987

840

perror("sigprocmask");

988

841

exitstatus = EXIT_FAILURE;

989

842

goto fallback;

990

843

}

991

844

992

FD_SET(new_plugin->fd, &rfds_all); /* Spurious warning from

993

-Wconversion */

845

FD_SET(new_plugin->fd, &rfds_all);

994

846

995

if(maxfd < new_plugin->fd){

847

if (maxfd < new_plugin->fd){

996

848

maxfd = new_plugin->fd;

997

849

}

850

998

851

}

999

852

1000

TEMP_FAILURE_RETRY(closedir(dir));

853

closedir(dir);

1001

854

dir = NULL;

1002

free_plugin(getplugin(NULL));

1003

855

1004

856

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

1005

857

if(p->pid != 0){

1006

858

break;

1011

863

free_plugin_list();

1012

864

}

1013

865

}

1014

866

1015

867

/* Main loop while running plugins exist */

1016

868

while(plugin_list){

1017

869

fd_set rfds = rfds_all;

1018

870

int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);

1019

if(select_ret == -1 and errno != EINTR){

871

if (select_ret == -1){

1020

872

perror("select");

1021

873

exitstatus = EXIT_FAILURE;

1022

874

goto fallback;

1023

875

}

1024

876

/* OK, now either a process completed, or something can be read

1025

877

from one of them */

1026

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

878

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

1027

879

/* Is this process completely done? */

1028

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

880

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

1029

881

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

1030

882

if(not WIFEXITED(proc->status)

1031

883

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

1032

884

/* Bad exit by plugin */

1033

885

1034

886

if(debug){

1035

887

if(WIFEXITED(proc->status)){

1036

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

1037

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

1038

(intmax_t) (proc->pid),

888

fprintf(stderr, "Plugin %u exited with status %d\n",

889

(unsigned int) (proc->pid),

1039

890

WEXITSTATUS(proc->status));

1040

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

1041

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

1042

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

1043

(intmax_t) (proc->pid),

1044

WTERMSIG(proc->status),

1045

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

891

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

892

fprintf(stderr, "Plugin %u killed by signal %d\n",

893

(unsigned int) (proc->pid),

894

WTERMSIG(proc->status));

1046

895

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

1047

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

1048

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

896

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

897

(unsigned int) (proc->pid));

1049

898

}

1050

899

}

1051

900

1052

901

/* Remove the plugin */

1053

FD_CLR(proc->fd, &rfds_all); /* Spurious warning from

1054

-Wconversion */

1055

902

FD_CLR(proc->fd, &rfds_all);

903

1056

904

/* Block signal while modifying process_list */

1057

ret = (int)TEMP_FAILURE_RETRY(sigprocmask

1058

(SIG_BLOCK,

1059

&sigchld_action.sa_mask,

1060

NULL));

905

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

1061

906

if(ret < 0){

1062

907

perror("sigprocmask");

1063

908

exitstatus = EXIT_FAILURE;

1064

909

goto fallback;

1065

910

}

1066

1067

plugin *next_plugin = proc->next;

1068

911

free_plugin(proc);

1069

proc = next_plugin;

1070

1071

912

/* We are done modifying process list, so unblock signal */

1072

ret = (int)(TEMP_FAILURE_RETRY

1073

(sigprocmask(SIG_UNBLOCK,

1074

&sigchld_action.sa_mask, NULL)));

913

ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,

914

NULL);

1075

915

if(ret < 0){

1076

916

perror("sigprocmask");

1077

917

exitstatus = EXIT_FAILURE;

1081

921

if(plugin_list == NULL){

1082

922

break;

1083

923

}

1084

1085

924

continue;

1086

925

}

1087

926

1088

927

/* This process exited nicely, so print its buffer */

1089

928

1090

929

bool bret = print_out_password(proc->buffer,

1091

930

proc->buffer_length);

1092

931

if(not bret){

1097

936

}

1098

937

1099

938

/* This process has not completed. Does it have any output? */

1100

if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious

1101

warning from

1102

-Wconversion */

939

if(proc->eof or not FD_ISSET(proc->fd, &rfds)){

1103

940

/* This process had nothing to say at this time */

1104

proc = proc->next;

1105

941

continue;

1106

942

}

1107

943

/* Before reading, make the process' data buffer large enough */

1108

944

if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){

1109

945

proc->buffer = realloc(proc->buffer, proc->buffer_size

1110

946

+ (size_t) BUFFER_SIZE);

1111

if(proc->buffer == NULL){

947

if (proc->buffer == NULL){

1112

948

perror("malloc");

1113

949

exitstatus = EXIT_FAILURE;

1114

950

goto fallback;

1116

952

proc->buffer_size += BUFFER_SIZE;

1117

953

}

1118

954

/* Read from the process */

1119

sret = TEMP_FAILURE_RETRY(read(proc->fd,

1120

proc->buffer

1121

+ proc->buffer_length,

1122

BUFFER_SIZE));

1123

if(sret < 0){

955

ret = read(proc->fd, proc->buffer + proc->buffer_length,

956

BUFFER_SIZE);

957

if(ret < 0){

1124

958

/* Read error from this process; ignore the error */

1125

proc = proc->next;

1126

959

continue;

1127

960

}

1128

if(sret == 0){

961

if(ret == 0){

1129

962

/* got EOF */

1130

963

proc->eof = true;

1131

964

} else {

1132

proc->buffer_length += (size_t) sret;

965

proc->buffer_length += (size_t) ret;

1133

966

}

1134

967

}

1135

968

}

1136

1137

969

970

1138

971

fallback:

1139

972

1140

973

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

1143

976

bool bret;

1144

977

fprintf(stderr, "Going to fallback mode using getpass(3)\n");

1145

978

char *passwordbuffer = getpass("Password: ");

1146

size_t len = strlen(passwordbuffer);

1147

/* Strip trailing newline */

1148

if(len > 0 and passwordbuffer[len-1] == '\n'){

1149

passwordbuffer[len-1] = '\0'; /* not strictly necessary */

1150

len--;

1151

}

1152

bret = print_out_password(passwordbuffer, len);

979

bret = print_out_password(passwordbuffer, strlen(passwordbuffer));

1153

980

if(not bret){

1154

981

perror("print_out_password");

1155

982

exitstatus = EXIT_FAILURE;

1162

989

perror("sigaction");

1163

990

exitstatus = EXIT_FAILURE;

1164

991

}

1165

992

1166

993

if(custom_argv != NULL){

1167

994

for(char **arg = custom_argv+1; *arg != NULL; arg++){

1168

995

free(*arg);

1174

1001

closedir(dir);

1175

1002

}

1176

1003

1177

/* Kill the processes */

1004

/* Free the process list and kill the processes */

1178

1005

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

1179

1006

if(p->pid != 0){

1180

1007

close(p->fd);

1187

1014

}

1188

1015

1189

1016

/* Wait for any remaining child processes to terminate */

1190

do {

1017

do{

1191

1018

ret = wait(NULL);

1192

1019

} while(ret >= 0);

1193

1020

if(errno != ECHILD){

1194

1021

perror("wait");

1195

1022

}

1196

1023

1197

1024

free_plugin_list();

1198

1025

1199

1026

free(plugindir);