/mandos/trunk : revision 323

1

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

1

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

2

/*

3

* Mandos plugin runner - Run Mandos plugins

4

*

38

#include <sys/select.h> /* fd_set, select(), FD_ZERO(),

39

FD_SET(), FD_ISSET(), FD_CLR */

40

#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),

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WEXITSTATUS(), WTERMSIG(),

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WCOREDUMP() */

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WEXITSTATUS() */

43

42

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

44

43

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

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44

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

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close() */

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

55

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FD_CLOEXEC */

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

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strsignal(), strcmp(), strncmp() */

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

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56

#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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}

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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));

116

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

111

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

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112

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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.disabled = false,

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.next = plugin_list };

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128

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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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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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new_plugin->argv[0] = copy_name;

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new_plugin->argv[1] = NULL;

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137

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

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if(new == NULL){

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return false;

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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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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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fd_set rfds_all;

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

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struct argp_state *state){

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char *tmp;

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switch(key){

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char *tmp;

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intmax_t tmpmax;

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

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if(arg != NULL){

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char *plugin_option;

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plugindir = strdup(arg);

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if(plugindir == NULL){

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perror("strdup");

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}

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}

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break;

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

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

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if(argfile == NULL){

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perror("strdup");

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}

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break;

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break;

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531

case 130: /* --userid */

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532

case 131: /* --groupid */

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case 132: /* --debug */

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conffp = fopen(AFILE, "r");

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} else {

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conffp = fopen(argfile, "r");

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}

565

}

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if(conffp != NULL){

587

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char *org_line = NULL;

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

632

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goto fallback;

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}

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custom_argv[custom_argc-1] = new_arg;

635

custom_argv[custom_argc] = NULL;

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custom_argv[custom_argc] = NULL;

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}

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}

638

do {

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ret = fclose(conffp);

640

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

641

if(ret == EOF){

642

perror("fclose");

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exitstatus = EXIT_FAILURE;

644

goto fallback;

645

}

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free(org_line);

647

619

} else {

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

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699

728

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

729

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while(true){

730

do {

731

dirst = readdir(dir);

732

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

702

dirst = readdir(dir);

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/* All directory entries have been processed */

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if(dirst == NULL){

771

741

for(const char **suf = bad_suffixes; *suf != NULL; suf++){

772

742

size_t suf_len = strlen(*suf);

773

743

if((d_name_len >= suf_len)

774

and (strcmp((dirst->d_name) + d_name_len-suf_len, *suf)

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and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)

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== 0)){

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746

if(debug){

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747

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

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790

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char *filename;

791

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if(plugindir == NULL){

792

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

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dirst->d_name));

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

794

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} else {

795

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

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plugindir,

797

dirst->d_name));

764

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

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765

}

799

766

if(ret < 0){

800

767

perror("asprintf");

801

768

continue;

802

769

}

803

770

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

771

ret = stat(filename, &st);

805

772

if(ret == -1){

806

773

perror("stat");

807

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free(filename);

809

776

}

810

777

811

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/* Ignore non-executable files */

812

if(not S_ISREG(st.st_mode)

813

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

779

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

814

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if(debug){

815

781

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

816

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

862

828

}

863

829

864

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int pipefd[2];

865

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

831

ret = pipe(pipefd);

866

832

if(ret == -1){

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833

perror("pipe");

868

834

exitstatus = EXIT_FAILURE;

882

848

goto fallback;

883

849

}

884

850

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

885

ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,

886

&sigchld_action.sa_mask,

887

NULL));

851

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

888

852

if(ret < 0){

889

853

perror("sigprocmask");

890

854

exitstatus = EXIT_FAILURE;

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goto fallback;

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}

893

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/* Starting a new process to be watched */

894

pid_t pid;

895

do {

896

pid = fork();

897

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

858

pid_t pid = fork();

898

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if(pid == -1){

899

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perror("fork");

900

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exitstatus = EXIT_FAILURE;

938

899

/* no return */

939

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}

940

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/* Parent process */

941

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

942

pipe */

902

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

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903

free(filename);

944

904

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

945

905

if(new_plugin == NULL){

946

906

perror("getplugin");

947

ret = (int)(TEMP_FAILURE_RETRY

948

(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,

949

NULL)));

907

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

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908

if(ret < 0){

951

909

perror("sigprocmask");

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910

}

959

917

960

918

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

961

919

has already completed */

962

ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,

963

&sigchld_action.sa_mask,

964

NULL));

920

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

965

921

if(ret < 0){

966

922

perror("sigprocmask");

967

923

exitstatus = EXIT_FAILURE;

968

924

goto fallback;

969

925

}

970

926

971

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

972

-Wconversion */

927

FD_SET(new_plugin->fd, &rfds_all);

973

928

974

929

if(maxfd < new_plugin->fd){

975

930

maxfd = new_plugin->fd;

976

931

}

977

932

}

978

933

979

TEMP_FAILURE_RETRY(closedir(dir));

934

closedir(dir);

980

935

dir = NULL;

981

936

free_plugin(getplugin(NULL));

982

937

995

950

while(plugin_list){

996

951

fd_set rfds = rfds_all;

997

952

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

998

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

953

if(select_ret == -1){

999

954

perror("select");

1000

955

exitstatus = EXIT_FAILURE;

1001

956

goto fallback;

1018

973

WEXITSTATUS(proc->status));

1019

974

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

1020

975

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

1021

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

976

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

1022

977

(intmax_t) (proc->pid),

1023

WTERMSIG(proc->status),

1024

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

978

WTERMSIG(proc->status));

1025

979

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

1026

980

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

1027

981

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

1029

983

}

1030

984

1031

985

/* Remove the plugin */

1032

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

1033

-Wconversion */

986

FD_CLR(proc->fd, &rfds_all);

1034

987

1035

988

/* Block signal while modifying process_list */

1036

ret = (int)TEMP_FAILURE_RETRY(sigprocmask

1037

(SIG_BLOCK,

1038

&sigchld_action.sa_mask,

1039

NULL));

989

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

1040

990

if(ret < 0){

1041

991

perror("sigprocmask");

1042

992

exitstatus = EXIT_FAILURE;

1048

998

proc = next_plugin;

1049

999

1050

1000

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

1051

ret = (int)(TEMP_FAILURE_RETRY

1052

(sigprocmask(SIG_UNBLOCK,

1053

&sigchld_action.sa_mask, NULL)));

1001

ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,

1002

NULL);

1054

1003

if(ret < 0){

1055

1004

perror("sigprocmask");

1056

1005

exitstatus = EXIT_FAILURE;

1076

1025

}

1077

1026

1078

1027

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

1079

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

1080

warning from

1081

-Wconversion */

1028

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

1082

1029

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

1083

1030

proc = proc->next;

1084

1031

continue;

1095

1042

proc->buffer_size += BUFFER_SIZE;

1096

1043

}

1097

1044

/* Read from the process */

1098

sret = TEMP_FAILURE_RETRY(read(proc->fd,

1099

proc->buffer

1100

+ proc->buffer_length,

1101

BUFFER_SIZE));

1045

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

1046

BUFFER_SIZE);

1102

1047

if(sret < 0){

1103

1048

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

1104

1049

proc = proc->next;

1166

1111

}

1167

1112

1168

1113

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

1169

do {

1114

do{

1170

1115

ret = wait(NULL);

1171

1116

} while(ret >= 0);

1172

1117

if(errno != ECHILD){