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21
* Contact the authors at <mandos@fukt.bsnet.se>.
24
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */
24
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
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26
#include <stddef.h> /* size_t, NULL */
27
27
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
28
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EXIT_SUCCESS, realloc() */
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52
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
54
#include <string.h> /* strtok, strlen(), strcpy(),
54
#include <string.h> /* strsep, strlen(), asprintf() */
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55
#include <errno.h> /* errno */
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56
#include <argp.h> /* struct argp_option, struct
58
57
argp_state, struct argp,
59
58
argp_parse(), ARGP_ERR_UNKNOWN,
60
ARGP_KEY_END, ARGP_KEY_ARG, error_t */
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ARGP_KEY_END, ARGP_KEY_ARG,
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61
#include <signal.h> /* struct sigaction, sigemptyset(),
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sigaddset(), sigaction(),
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63
sigprocmask(), SIG_BLOCK, SIGCHLD,
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106
/* Create a new plugin */
102
107
plugin *new_plugin = malloc(sizeof(plugin));
103
108
if (new_plugin == NULL){
107
new_plugin->name = name;
111
char *copy_name = NULL;
113
copy_name = strdup(name);
114
if(copy_name == NULL){
119
*new_plugin = (plugin) { .name = copy_name,
123
.next = *plugin_list };
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125
new_plugin->argv = malloc(sizeof(char *) * 2);
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126
if (new_plugin->argv == NULL){
113
new_plugin->argv[0] = name;
131
new_plugin->argv[0] = copy_name;
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132
new_plugin->argv[1] = NULL;
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new_plugin->argc = 1;
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new_plugin->disabled = false;
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new_plugin->next = *plugin_list;
134
new_plugin->environ = malloc(sizeof(char *));
135
if(new_plugin->environ == NULL){
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free(new_plugin->argv);
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new_plugin->environ[0] = NULL;
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142
/* Append the new plugin to the list */
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143
*plugin_list = new_plugin;
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return new_plugin;
123
static void addargument(plugin *p, char *arg){
124
p->argv[p->argc] = arg;
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p->argv = realloc(p->argv, sizeof(char *) * (size_t)(p->argc + 2));
126
if (p->argv == NULL){
131
p->argv[p->argc] = NULL;
147
/* Helper function for add_argument and add_environment */
148
static bool add_to_char_array(const char *new, char ***array,
150
/* Resize the pointed-to array to hold one more pointer */
151
*array = realloc(*array, sizeof(char *)
152
* (size_t) ((*len) + 2));
157
/* Make a copy of the new string */
158
char *copy = strdup(new);
162
/* Insert the copy */
163
(*array)[*len] = copy;
165
/* Add a new terminating NULL pointer to the last element */
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(*array)[*len] = NULL;
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/* Add to a plugin's argument vector */
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static bool add_argument(plugin *p, const char *arg){
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return add_to_char_array(arg, &(p->argv), &(p->argc));
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/* Add to a plugin's environment */
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static bool add_environment(plugin *p, const char *def){
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return add_to_char_array(def, &(p->environ), &(p->envc));
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188
* Based on the example in the GNU LibC manual chapter 13.13 "File
150
203
process *process_list = NULL;
152
/* Mark a process as completed when it exits, and save its exit
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/* Mark processes as completed when they exit, and save their exit
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207
void handle_sigchld(__attribute__((unused)) int sig){
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process *proc = process_list;
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pid_t pid = wait(&status);
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while(proc != NULL and proc->pid != pid){
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/* Process not found in process list */
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proc->status = status;
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proc->completed = true;
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process *proc = process_list;
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pid_t pid = waitpid(-1, &status, WNOHANG);
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/* Only still running child processes */
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if (errno != ECHILD){
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/* No child processes */
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/* A child exited, find it in process_list */
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while(proc != NULL and proc->pid != pid){
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/* Process not found in process list */
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proc->status = status;
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proc->completed = true;
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bool print_out_password(const char *buffer, size_t length){
239
if(length>0 and buffer[length-1] == '\n'){
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for(size_t written = 0; written < length; written += (size_t)ret){
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ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
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static void free_plugin_list(plugin *plugin_list){
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for(plugin *next; plugin_list != NULL; plugin_list = next){
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next = plugin_list->next;
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for(char **arg = plugin_list->argv; *arg != NULL; arg++){
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free(plugin_list->argv);
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for(char **env = plugin_list->environ; *env != NULL; env++){
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free(plugin_list->environ);
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267
int main(int argc, char *argv[]){
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const char *plugindir = "/conf/conf.d/mandos/plugins.d";
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char *plugindir = NULL;
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char *argfile = NULL;
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271
size_t d_name_len;
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273
struct dirent *dirst;
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281
struct sigaction old_sigchld_action;
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struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
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283
.sa_flags = SA_NOCLDSTOP };
188
char *plus_options = NULL;
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char **plus_argv = NULL;
284
char **custom_argv = NULL;
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287
/* Establish a signal handler */
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288
sigemptyset(&sigchld_action.sa_mask);
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289
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
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291
perror("sigaddset");
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exitstatus = EXIT_FAILURE;
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295
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
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297
perror("sigaction");
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exitstatus = EXIT_FAILURE;
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302
/* The options we understand. */
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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-envs", .key = 'e',
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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 = "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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.doc = "Disable a specific plugin", .group = 1 },
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{ .name = "plugin-dir", .key = 128,
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.arg = "DIRECTORY",
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.doc = "Specify a different plugin directory", .group = 2 },
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{ .name = "userid", .key = 129,
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.arg = "ID", .flags = 0,
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.doc = "User ID the plugins will run as", .group = 2 },
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{ .name = "groupid", .key = 130,
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.arg = "ID", .flags = 0,
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.doc = "Group ID the plugins will run as", .group = 2 },
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{ .name = "debug", .key = 131,
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.doc = "Debug mode", .group = 3 },
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{ .name = "config-file", .key = 129,
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.doc = "Specify a different configuration file", .group = 2 },
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{ .name = "userid", .key = 130,
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.arg = "ID", .flags = 0,
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.doc = "User ID the plugins will run as", .group = 3 },
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{ .name = "groupid", .key = 131,
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.arg = "ID", .flags = 0,
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.doc = "Group ID the plugins will run as", .group = 3 },
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{ .name = "debug", .key = 132,
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.doc = "Debug mode", .group = 4 },
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if (arg != NULL){
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char *p = strtok(arg, ",");
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addargument(getplugin(NULL, plugins), p);
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p = strtok(NULL, ",");
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while((p = strsep(&arg, ",")) != NULL){
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if(not add_argument(getplugin(NULL, plugins), p)){
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perror("add_argument");
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return ARGP_ERR_UNKNOWN;
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char *envdef = strdup(arg);
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if(not add_environment(getplugin(NULL, plugins), envdef)){
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perror("add_environment");
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370
if (arg != NULL){
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char *name = strtok(arg, ":");
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char *p = strtok(NULL, ":");
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addargument(getplugin(name, plugins), p);
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p = strtok(NULL, ",");
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char *p_name = strsep(&arg, ":");
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if(p_name[0] == '\0'){
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char *opt = strsep(&arg, ":");
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while((p = strsep(&opt, ",")) != NULL){
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if(not add_argument(getplugin(p_name, plugins), p)){
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perror("add_argument");
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return ARGP_ERR_UNKNOWN;
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char *envdef = strchr(arg, ':');
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char *p_name = strndup(arg, (size_t) (envdef-arg));
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if(not add_environment(getplugin(p_name, plugins), envdef)){
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perror("add_environment");
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if (arg != NULL){
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getplugin(arg, plugins)->disabled = true;
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plugin *p = getplugin(arg, plugins);
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return ARGP_ERR_UNKNOWN;
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plugindir = strdup(arg);
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if(plugindir == NULL){
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argfile = strdup(arg);
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uid = (uid_t)strtol(arg, NULL, 10);
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437
gid = (gid_t)strtol(arg, NULL, 10);
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442
case ARGP_KEY_ARG:
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if(plus_options != NULL or arg == NULL or arg[0] != '+'){
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fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
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445
case ARGP_KEY_END:
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459
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
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if (ret == ARGP_ERR_UNKNOWN){
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fprintf(stderr, "Unkown error while parsing arguments\n");
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fprintf(stderr, "Unknown error while parsing arguments\n");
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exitstatus = EXIT_FAILURE;
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if (argfile == NULL){
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conffp = fopen(AFILE, "r");
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conffp = fopen(argfile, "r");
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/* This is a mangled argument in the form of
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"+--option+--other-option=parameter+--yet-another-option", etc */
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/* Make new argc and argv vars, and call argp_parse() again. */
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plus_options++; /* skip the first '+' character */
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const char delims[] = "+";
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plus_argv = malloc(sizeof(char*) * 2);
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if(plus_argv == NULL){
473
char *org_line = NULL;
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char *p, *arg, *new_arg, *line;
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const char whitespace_delims[] = " \r\t\f\v\n";
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const char comment_delim[] = "#";
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custom_argv = malloc(sizeof(char*) * 2);
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if(custom_argv == NULL){
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483
perror("malloc");
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484
exitstatus = EXIT_FAILURE;
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plus_argv[0] = argv[0];
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arg = strtok(plus_options, delims); /* Get first argument */
319
plus_argv = realloc(plus_argv, sizeof(char *)
320
* ((unsigned int) new_argc + 1));
321
if(plus_argv == NULL){
323
exitstatus = EXIT_FAILURE;
326
plus_argv[new_argc-1] = arg;
327
plus_argv[new_argc] = NULL;
328
arg = strtok(NULL, delims); /* Get next argument */
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ret = argp_parse (&argp, new_argc, plus_argv, 0, 0, &plugin_list);
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custom_argv[0] = argv[0];
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custom_argv[1] = NULL;
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sret = getline(&org_line, &size, conffp);
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arg = strsep(&line, comment_delim);
498
while((p = strsep(&arg, whitespace_delims)) != NULL){
505
exitstatus = EXIT_FAILURE;
511
custom_argv = realloc(custom_argv, sizeof(char *)
512
* ((unsigned int) custom_argc + 1));
513
if(custom_argv == NULL){
515
exitstatus = EXIT_FAILURE;
519
custom_argv[custom_argc-1] = new_arg;
520
custom_argv[custom_argc] = NULL;
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/* Check for harmful errors and go to fallback. Other errors might
526
not affect opening plugins */
527
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
529
exitstatus = EXIT_FAILURE;
534
if(custom_argv != NULL){
535
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);
331
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if (ret == ARGP_ERR_UNKNOWN){
332
fprintf(stderr, "Unkown error while parsing arguments\n");
537
fprintf(stderr, "Unknown error while parsing arguments\n");
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exitstatus = EXIT_FAILURE;
440
char *filename = malloc(d_name_len + strlen(plugindir) + 2);
441
if (filename == NULL){
443
exitstatus = EXIT_FAILURE;
655
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
446
strcpy(filename, plugindir); /* Spurious warning */
447
strcat(filename, "/"); /* Spurious warning */
448
strcat(filename, dirst->d_name); /* Spurious warning */
450
661
ret = stat(filename, &st);
453
exitstatus = EXIT_FAILURE;
457
668
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
473
plugin *p = getplugin(dirst->d_name, &plugin_list);
475
691
/* Add global arguments to argument list for this plugin */
476
692
plugin *g = getplugin(NULL, &plugin_list);
477
for(char **a = g->argv + 1; *a != NULL; a++){
694
for(char **a = g->argv + 1; *a != NULL; a++){
695
if(not add_argument(p, *a)){
696
perror("add_argument");
699
/* Add global environment variables */
700
for(char **e = g->environ; *e != NULL; e++){
701
if(not add_environment(p, *e)){
702
perror("add_environment");
707
/* If this plugin has any environment variables, we will call
708
using execve and need to duplicate the environment from this
710
if(p->environ[0] != NULL){
711
for(char **e = environ; *e != NULL; e++){
712
char *copy = strdup(*e);
717
if(not add_environment(p, copy)){
718
perror("add_environment");
482
724
ret = pipe(pipefd);
485
727
exitstatus = EXIT_FAILURE;
488
730
ret = set_cloexec_flag(pipefd[0]);
490
732
perror("set_cloexec_flag");
491
733
exitstatus = EXIT_FAILURE;
494
736
ret = set_cloexec_flag(pipefd[1]);
496
738
perror("set_cloexec_flag");
497
739
exitstatus = EXIT_FAILURE;
500
742
/* Block SIGCHLD until process is safely in process list */
501
743
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
503
745
perror("sigprocmask");
504
746
exitstatus = EXIT_FAILURE;
507
749
// Starting a new process to be watched
508
750
pid_t pid = fork();
753
exitstatus = EXIT_FAILURE;
510
757
/* this is the child process */
511
758
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
575
/* Free the plugin list */
576
for(plugin *next; plugin_list != NULL; plugin_list = next){
577
next = plugin_list->next;
578
free(plugin_list->argv);
829
free_plugin_list(plugin_list);
585
835
if (process_list == NULL){
586
fprintf(stderr, "No plugin processes started, exiting\n");
587
exitstatus = EXIT_FAILURE;
836
fprintf(stderr, "No plugin processes started. Incorrect plugin"
590
840
while(process_list){
591
841
fd_set rfds = rfds_all;
621
871
/* Remove the plugin */
622
872
FD_CLR(proc->fd, &rfds_all);
623
873
/* Block signal while modifying process_list */
624
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
874
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
626
876
perror("sigprocmask");
627
877
exitstatus = EXIT_FAILURE;
630
880
/* Delete this process entry from the list */
631
881
if(process_list == proc){
656
906
/* This process exited nicely, so print its buffer */
657
for(size_t written = 0; written < proc->buffer_length;
658
written += (size_t)ret){
659
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO,
660
proc->buffer + written,
665
exitstatus = EXIT_FAILURE;
908
bool bret = print_out_password(proc->buffer,
909
proc->buffer_length);
911
perror("print_out_password");
912
exitstatus = EXIT_FAILURE;
671
916
/* This process has not completed. Does it have any output? */
672
917
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
702
if(process_list == NULL){
703
fprintf(stderr, "All plugin processes failed, exiting\n");
704
exitstatus = EXIT_FAILURE;
951
if(process_list == NULL or exitstatus != EXIT_SUCCESS){
952
/* Fallback if all plugins failed, none are found or an error
955
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
956
char *passwordbuffer = getpass("Password: ");
957
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
959
perror("print_out_password");
960
exitstatus = EXIT_FAILURE;
708
964
/* Restore old signal handler */
709
sigaction(SIGCHLD, &old_sigchld_action, NULL);
713
/* Free the plugin list */
714
for(plugin *next; plugin_list != NULL; plugin_list = next){
715
next = plugin_list->next;
716
free(plugin_list->argv);
965
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
968
exitstatus = EXIT_FAILURE;
971
if(custom_argv != NULL){
972
for(char **arg = custom_argv+1; *arg != NULL; arg++){
977
free_plugin_list(plugin_list);