/mandos/release : revision 237.2.84

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(),

41

WEXITSTATUS(), WTERMSIG(),

42

WCOREDUMP() */

41

WEXITSTATUS() */

43

42

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

44

43

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

45

44

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

53

52

close() */

54

53

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

55

54

FD_CLOEXEC */

56

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

57

strsignal() */

55

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

58

56

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

59

57

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

60

58

argp_state, struct argp,

110

108

}

111

109

}

112

110

/* Create a new plugin */

113

plugin *new_plugin = NULL;

114

do {

115

new_plugin = malloc(sizeof(plugin));

116

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

111

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

117

112

if(new_plugin == NULL){

118

113

return NULL;

119

114

}

120

115

char *copy_name = NULL;

121

116

if(name != NULL){

122

do {

123

copy_name = strdup(name);

124

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

117

copy_name = strdup(name);

125

118

if(copy_name == NULL){

126

119

free(new_plugin);

127

120

return NULL;

133

126

.disabled = false,

134

127

.next = plugin_list };

135

128

136

do {

137

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

138

} while(new_plugin->argv == NULL and errno == EINTR);

129

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

139

130

if(new_plugin->argv == NULL){

140

131

free(copy_name);

141

132

free(new_plugin);

144

135

new_plugin->argv[0] = copy_name;

145

136

new_plugin->argv[1] = NULL;

146

137

147

do {

148

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

149

} while(new_plugin->environ == NULL and errno == EINTR);

138

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

150

139

if(new_plugin->environ == NULL){

151

140

free(copy_name);

152

141

free(new_plugin->argv);

164

153

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

165

154

int *len){

166

155

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

167

do {

168

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

169

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

170

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

156

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

157

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

171

158

/* Malloc check */

172

159

if(*array == NULL){

173

160

return false;

174

161

}

175

162

/* Make a copy of the new string */

176

char *copy;

177

do {

178

copy = strdup(new);

179

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

163

char *copy = strdup(new);

180

164

if(copy == NULL){

181

165

return false;

182

166

}

208

192

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

209

193

/* It already exists */

210

194

if(replace){

211

char *new;

212

do {

213

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

214

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

195

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

215

196

if(new == NULL){

216

197

return false;

217

198

}

227

208

/*

228

209

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

229

210

* Descriptor Flags".

230

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

211

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

231

212

*/

232

213

static int set_cloexec_flag(int fd){

233

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

214

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

234

215

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

235

216

if(ret < 0){

236

217

return ret;

237

218

}

238

219

/* Store modified flag word in the descriptor. */

239

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

220

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

240

221

}

241

222

242

223

334

315

fd_set rfds_all;

335

316

int ret, maxfd = 0;

336

317

ssize_t sret;

318

intmax_t tmpmax;

337

319

uid_t uid = 65534;

338

320

gid_t gid = 65534;

339

321

bool debug = false;

398

380

399

381

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

400

382

struct argp_state *state){

383

char *tmp;

401

384

switch(key){

402

char *tmp;

403

intmax_t tmpmax;

404

385

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

405

386

if(arg != NULL){

406

387

char *plugin_option;

476

457

plugindir = strdup(arg);

477

458

if(plugindir == NULL){

478

459

perror("strdup");

479

}

460

}

480

461

break;

481

462

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

482

463

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

546

527

if(argfile == NULL){

547

528

perror("strdup");

548

529

}

549

break;

530

break;

550

531

case 130: /* --userid */

551

532

case 131: /* --groupid */

552

533

case 132: /* --debug */

581

562

conffp = fopen(AFILE, "r");

582

563

} else {

583

564

conffp = fopen(argfile, "r");

584

}

565

}

585

566

if(conffp != NULL){

586

567

char *org_line = NULL;

587

568

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

631

612

goto fallback;

632

613

}

633

614

custom_argv[custom_argc-1] = new_arg;

634

custom_argv[custom_argc] = NULL;

615

custom_argv[custom_argc] = NULL;

635

616

}

636

617

}

637

do {

638

ret = fclose(conffp);

639

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

640

if(ret == EOF){

641

perror("fclose");

642

exitstatus = EXIT_FAILURE;

643

goto fallback;

644

}

645

618

free(org_line);

646

619

} else {

647

620

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

726

699

727

700

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

728

701

while(true){

729

do {

730

dirst = readdir(dir);

731

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

702

dirst = readdir(dir);

732

703

733

704

/* All directory entries have been processed */

734

705

if(dirst == NULL){

788

759

789

760

char *filename;

790

761

if(plugindir == NULL){

791

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

792

dirst->d_name));

762

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

793

763

} else {

794

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

795

dirst->d_name));

764

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

796

765

}

797

766

if(ret < 0){

798

767

perror("asprintf");

799

768

continue;

800

769

}

801

770

802

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

771

ret = stat(filename, &st);

803

772

if(ret == -1){

804

773

perror("stat");

805

774

free(filename);

807

776

}

808

777

809

778

/* Ignore non-executable files */

810

if(not S_ISREG(st.st_mode)

811

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

779

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

812

780

if(debug){

813

781

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

814

782

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

860

828

}

861

829

862

830

int pipefd[2];

863

ret = TEMP_FAILURE_RETRY(pipe(pipefd));

831

ret = pipe(pipefd);

864

832

if(ret == -1){

865

833

perror("pipe");

866

834

exitstatus = EXIT_FAILURE;

880

848

goto fallback;

881

849

}

882

850

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

883

ret = TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,

884

&sigchld_action.sa_mask,

885

NULL));

851

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

886

852

if(ret < 0){

887

853

perror("sigprocmask");

888

854

exitstatus = EXIT_FAILURE;

889

855

goto fallback;

890

856

}

891

857

/* Starting a new process to be watched */

892

pid_t pid;

893

do {

894

pid = fork();

895

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

858

pid_t pid = fork();

896

859

if(pid == -1){

897

860

perror("fork");

898

861

exitstatus = EXIT_FAILURE;

936

899

/* no return */

937

900

}

938

901

/* Parent process */

939

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

940

pipe */

902

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

941

903

free(filename);

942

904

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

943

905

if(new_plugin == NULL){

944

906

perror("getplugin");

945

ret = TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,

946

&sigchld_action.sa_mask,

947

NULL));

907

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

948

908

if(ret < 0){

949

909

perror("sigprocmask");

950

910

}

957

917

958

918

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

959

919

has already completed */

960

ret = TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,

961

&sigchld_action.sa_mask,

962

NULL));

920

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

963

921

if(ret < 0){

964

922

perror("sigprocmask");

965

923

exitstatus = EXIT_FAILURE;

973

931

}

974

932

}

975

933

976

TEMP_FAILURE_RETRY(closedir(dir));

934

closedir(dir);

977

935

dir = NULL;

978

936

free_plugin(getplugin(NULL));

979

937

992

950

while(plugin_list){

993

951

fd_set rfds = rfds_all;

994

952

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

995

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

953

if(select_ret == -1){

996

954

perror("select");

997

955

exitstatus = EXIT_FAILURE;

998

956

goto fallback;

1015

973

WEXITSTATUS(proc->status));

1016

974

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

1017

975

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

1018

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

976

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

1019

977

(intmax_t) (proc->pid),

1020

WTERMSIG(proc->status),

1021

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

978

WTERMSIG(proc->status));

1022

979

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

1023

980

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

1024

981

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

1029

986

FD_CLR(proc->fd, &rfds_all);

1030

987

1031

988

/* Block signal while modifying process_list */

1032

ret = TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,

1033

&sigchld_action.sa_mask,

1034

NULL));

989

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

1035

990

if(ret < 0){

1036

991

perror("sigprocmask");

1037

992

exitstatus = EXIT_FAILURE;

1043

998

proc = next_plugin;

1044

999

1045

1000

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

1046

ret = TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,

1047

&sigchld_action.sa_mask,

1048

NULL));

1001

ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,

1002

NULL);

1049

1003

if(ret < 0){

1050

1004

perror("sigprocmask");

1051

1005

exitstatus = EXIT_FAILURE;

1088

1042

proc->buffer_size += BUFFER_SIZE;

1089

1043

}

1090

1044

/* Read from the process */

1091

sret = TEMP_FAILURE_RETRY(read(proc->fd,

1092

proc->buffer

1093

+ proc->buffer_length,

1094

BUFFER_SIZE));

1045

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

1046

BUFFER_SIZE);

1095

1047

if(sret < 0){

1096

1048

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

1097

1049

proc = proc->next;

1159

1111

}

1160

1112

1161

1113

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

1162

do {

1114

do{

1163

1115

ret = wait(NULL);

1164

1116

} while(ret >= 0);

1165

1117

if(errno != ECHILD){