/mandos/trunk : revision 305

64

sigprocmask(), SIG_BLOCK, SIGCHLD,

65

SIG_UNBLOCK, kill() */

66

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

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#include <inttypes.h> /* intmax_t, SCNdMAX, PRIdMAX, */

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#define BUFFER_SIZE 256

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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 bool completed;

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volatile int status;

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volatile sig_atomic_t completed;

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int status;

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struct plugin *next;

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} plugin;

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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 = malloc(sizeof(plugin));

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if (new_plugin == NULL){

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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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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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*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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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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/* 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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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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perror("waitpid");

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if(errno == ECHILD){

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/* No child processes */

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break;

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}

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/* No child processes */

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break;

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perror("waitpid");

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}

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

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continue;

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}

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proc->status = status;

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proc->completed = true;

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proc->completed = 1;

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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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struct dirent *dirst;

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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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int ret, numchars, maxfd = 0;

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ssize_t sret;

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intmax_t tmpmax;

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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 = NULL }

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};

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

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struct argp_state *state) {

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switch (key) {

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

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struct argp_state *state){

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switch(key){

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

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if (arg != NULL){

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if(arg != NULL){

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char *p;

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

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

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}

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break;

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

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if (arg != NULL){

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if(arg != NULL){

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

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if(p_name[0] == '\0' or arg == NULL){

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break;

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}

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break;

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

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if (arg != NULL){

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if(arg != NULL){

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plugin *p = getplugin(arg);

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if(p == NULL){

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return ARGP_ERR_UNKNOWN;

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}

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break;

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

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if (arg != NULL){

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if(arg != NULL){

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plugin *p = getplugin(arg);

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if(p == NULL){

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return ARGP_ERR_UNKNOWN;

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

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break;

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case 130: /* --userid */

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/* In the GNU C library, uid_t is always unsigned int */

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ret = sscanf(arg, "%ud", &uid);

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if(ret != 1){

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

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arg, uid);

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ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);

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if(ret < 1 or tmpmax != (uid_t)tmpmax

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or arg[numchars] != '\0'){

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

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

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} else {

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uid = (uid_t)tmpmax;

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}

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break;

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case 131: /* --groupid */

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/* In the GNU C library, gid_t is always unsigned int */

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ret = sscanf(arg, "%ud", &gid);

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if(ret != 1){

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

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arg, gid);

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ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);

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if(ret < 1 or tmpmax != (gid_t)tmpmax

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or arg[numchars] != '\0'){

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

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

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} else {

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gid = (gid_t)tmpmax;

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}

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break;

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case 132: /* --debug */

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

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

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error_t parse_opt_config_file (int key, char *arg,

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__attribute__((unused))

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struct argp_state *state) {

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switch (key) {

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error_t parse_opt_config_file(int key, char *arg,

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__attribute__((unused))

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struct argp_state *state){

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switch(key){

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

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

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

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.args_doc = "",

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

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

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

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config file location, if any. */

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

545

if (ret == ARGP_ERR_UNKNOWN){

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

554

if(ret == ARGP_ERR_UNKNOWN){

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

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exitstatus = EXIT_FAILURE;

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goto fallback;

552

561

argp.parser = parse_opt;

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554

563

/* Open the configfile if available */

555

if (argfile == NULL){

564

if(argfile == NULL){

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565

conffp = fopen(AFILE, "r");

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566

} else {

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conffp = fopen(argfile, "r");

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622

} else {

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623

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

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not affect opening plugins */

616

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

625

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

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perror("fopen");

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exitstatus = EXIT_FAILURE;

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628

goto fallback;

622

631

/* If there was any arguments from configuration file,

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632

pass them to parser as command arguments */

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633

if(custom_argv != NULL){

625

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

626

0, NULL);

627

if (ret == ARGP_ERR_UNKNOWN){

634

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

635

0, NULL);

636

if(ret == ARGP_ERR_UNKNOWN){

628

637

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

629

638

exitstatus = EXIT_FAILURE;

630

639

goto fallback;

633

642

634

643

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

635

644

config file */

636

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

637

if (ret == ARGP_ERR_UNKNOWN){

645

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

646

if(ret == ARGP_ERR_UNKNOWN){

638

647

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

639

648

exitstatus = EXIT_FAILURE;

640

649

goto fallback;

647

656

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

648

657

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

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658

}

650

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

659

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

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660

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

652

661

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

653

662

}

655

664

}

656

665

657

666

/* Strip permissions down to nobody */

667

setgid(gid);

668

if(ret == -1){

669

perror("setgid");

670

}

658

671

ret = setuid(uid);

659

if (ret == -1){

672

if(ret == -1){

660

673

perror("setuid");

661

}

662

setgid(gid);

663

if (ret == -1){

664

perror("setgid");

665

674

}

666

675

667

if (plugindir == NULL){

676

if(plugindir == NULL){

668

677

dir = opendir(PDIR);

669

678

} else {

670

679

dir = opendir(plugindir);

697

706

698

707

/* All directory entries have been processed */

699

708

if(dirst == NULL){

700

if (errno == EBADF){

709

if(errno == EBADF){

701

710

perror("readdir");

702

711

exitstatus = EXIT_FAILURE;

703

712

goto fallback;

763

772

}

764

773

765

774

ret = stat(filename, &st);

766

if (ret == -1){

775

if(ret == -1){

767

776

perror("stat");

768

777

free(filename);

769

778

continue;

770

779

}

771

780

772

781

/* Ignore non-executable files */

773

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

782

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

774

783

if(debug){

775

784

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

776

785

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

823

832

824

833

int pipefd[2];

825

834

ret = pipe(pipefd);

826

if (ret == -1){

835

if(ret == -1){

827

836

perror("pipe");

828

837

exitstatus = EXIT_FAILURE;

829

838

goto fallback;

842

851

goto fallback;

843

852

}

844

853

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

845

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

854

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

846

855

if(ret < 0){

847

856

perror("sigprocmask");

848

857

exitstatus = EXIT_FAILURE;

896

905

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

897

906

free(filename);

898

907

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

899

if (new_plugin == NULL){

908

if(new_plugin == NULL){

900

909

perror("getplugin");

901

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

910

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

902

911

if(ret < 0){

903

912

perror("sigprocmask");

904

913

}

911

920

912

921

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

913

922

has already completed */

914

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

923

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

915

924

if(ret < 0){

916

925

perror("sigprocmask");

917

926

exitstatus = EXIT_FAILURE;

920

929

921

930

FD_SET(new_plugin->fd, &rfds_all);

922

931

923

if (maxfd < new_plugin->fd){

932

if(maxfd < new_plugin->fd){

924

933

maxfd = new_plugin->fd;

925

934

}

926

935

}

943

952

while(plugin_list){

944

953

fd_set rfds = rfds_all;

945

954

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

946

if (select_ret == -1){

955

if(select_ret == -1){

947

956

perror("select");

948

957

exitstatus = EXIT_FAILURE;

949

958

goto fallback;

952

961

from one of them */

953

962

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

954

963

/* Is this process completely done? */

955

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

964

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

956

965

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

957

966

if(not WIFEXITED(proc->status)

958

967

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

960

969

961

970

if(debug){

962

971

if(WIFEXITED(proc->status)){

963

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

964

(unsigned int) (proc->pid),

972

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

973

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

974

(intmax_t) (proc->pid),

965

975

WEXITSTATUS(proc->status));

966

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

967

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

968

(unsigned int) (proc->pid),

976

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

977

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

978

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

979

(intmax_t) (proc->pid),

969

980

WTERMSIG(proc->status));

970

981

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

971

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

972

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

982

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

983

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

973

984

}

974

985

}

975

986

989

1000

proc = next_plugin;

990

1001

991

1002

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

992

ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,

993

NULL);

1003

ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,

1004

NULL);

994

1005

if(ret < 0){

995

1006

perror("sigprocmask");

996

1007

exitstatus = EXIT_FAILURE;

1025

1036

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

1026

1037

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

1027

1038

+ (size_t) BUFFER_SIZE);

1028

if (proc->buffer == NULL){

1039

if(proc->buffer == NULL){

1029

1040

perror("malloc");

1030

1041

exitstatus = EXIT_FAILURE;

1031

1042

goto fallback;