/mandos/release : revision 24.1.51

21

* Contact the authors at <mandos@fukt.bsnet.se>.

22

*/

23

24

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

25

asprintf() */

24

#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */

25

26

#include <stddef.h> /* size_t, NULL */

27

#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,

28

EXIT_SUCCESS, realloc() */

51

close() */

52

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

53

FD_CLOEXEC */

54

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

54

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

55

strcat() */

55

56

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

56

57

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

57

58

argp_state, struct argp,

58

59

argp_parse(), ARGP_ERR_UNKNOWN,

59

ARGP_KEY_END, ARGP_KEY_ARG,

60

error_t */

60

ARGP_KEY_END, ARGP_KEY_ARG, error_t */

61

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

62

sigaddset(), sigaction(),

63

sigprocmask(), SIG_BLOCK, SIGCHLD,

65

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

66

67

#define BUFFER_SIZE 256

68

#define ARGFILE "/conf/conf.d/mandos/plugin-runner.conf"

68

#define CONFFILE "/conf/conf.d/mandos/client.conf"

69

70

const char *argp_program_version = "plugin-runner 1.0";

70

const char *argp_program_version = "mandos-client 1.0";

71

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

72

73

struct process;

79

size_t buffer_size;

80

size_t buffer_length;

81

bool eof;

82

volatile bool completed;

83

volatile int status;

82

bool completed;

83

int status;

84

struct process *next;

85

} process;

86

88

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

89

char **argv;

90

int argc;

91

char **environ;

92

int envc;

93

91

bool disabled;

94

92

struct plugin *next;

95

93

} plugin;

104

102

/* Create a new plugin */

105

103

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

106

104

if (new_plugin == NULL){

107

return NULL;

108

}

109

char *copy_name = NULL;

110

if(name != NULL){

111

copy_name = strdup(name);

112

if(copy_name == NULL){

113

return NULL;

114

}

115

}

116

117

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

118

.argc = 1,

119

.envc = 0,

120

.disabled = false,

121

.next = *plugin_list };

122

105

perror("malloc");

106

exit(EXIT_FAILURE);

107

}

108

new_plugin->name = name;

123

109

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

124

110

if (new_plugin->argv == NULL){

125

free(copy_name);

126

free(new_plugin);

127

return NULL;

111

perror("malloc");

112

exit(EXIT_FAILURE);

128

113

}

129

new_plugin->argv[0] = copy_name;

114

new_plugin->argv[0] = name;

130

115

new_plugin->argv[1] = NULL;

131

132

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

133

if(new_plugin->environ == NULL){

134

free(copy_name);

135

free(new_plugin->argv);

136

free(new_plugin);

137

return NULL;

138

}

139

new_plugin->environ[0] = NULL;

116

new_plugin->argc = 1;

117

new_plugin->disabled = false;

118

new_plugin->next = *plugin_list;

140

119

/* Append the new plugin to the list */

141

120

*plugin_list = new_plugin;

142

121

return new_plugin;

143

122

}

144

123

145

/* Helper function for add_argument and add_environment */

146

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

147

int *len){

148

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

149

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

150

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

151

/* Malloc check */

152

if(*array == NULL){

153

return false;

154

}

155

/* Make a copy of the new string */

156

char *copy = strdup(new);

157

if(copy == NULL){

158

return false;

159

}

160

/* Insert the copy */

161

(*array)[*len] = copy;

162

(*len)++;

163

/* Add a new terminating NULL pointer to the last element */

164

(*array)[*len] = NULL;

165

return true;

166

}

167

168

/* Add to a plugin's argument vector */

169

static bool add_argument(plugin *p, const char *arg){

170

if(p == NULL){

171

return false;

172

}

173

return add_to_char_array(arg, &(p->argv), &(p->argc));

174

}

175

176

/* Add to a plugin's environment */

177

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

178

if(p == NULL){

179

return false;

180

}

181

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

182

}

183

124

static void addargument(plugin *p, char *arg){

125

p->argv[p->argc] = arg;

126

p->argv = realloc(p->argv, sizeof(char *) * (size_t)(p->argc + 2));

127

if (p->argv == NULL){

128

perror("malloc");

129

exit(EXIT_FAILURE);

130

}

131

p->argc++;

132

p->argv[p->argc] = NULL;

133

}

184

134

185

135

/*

186

136

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

200

150

201

151

process *process_list = NULL;

202

152

203

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

153

/* Mark a process as completed when it exits, and save its exit

204

154

status. */

205

155

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

206

while(true){

207

process *proc = process_list;

208

int status;

209

pid_t pid = waitpid(-1, &status, WNOHANG);

210

if(pid == 0){

211

/* Only still running child processes */

212

break;

213

}

214

if(pid == -1){

215

if (errno != ECHILD){

216

perror("waitpid");

217

}

218

/* No child processes */

219

break;

220

}

221

222

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

223

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

224

proc = proc->next;

225

}

226

if(proc == NULL){

227

/* Process not found in process list */

228

continue;

229

}

230

proc->status = status;

231

proc->completed = true;

232

}

156

process *proc = process_list;

157

int status;

158

pid_t pid = wait(&status);

159

if(pid == -1){

160

perror("wait");

161

return;

162

}

163

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

164

proc = proc->next;

165

}

166

if(proc == NULL){

167

/* Process not found in process list */

168

return;

169

}

170

proc->status = status;

171

proc->completed = true;

233

172

}

234

173

235

174

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

247

186

return true;

248

187

}

249

188

250

char **add_to_argv(char **argv, int *argc, char *arg){

189

char ** addcustomargument(char **argv, int *argc, char *arg){

190

251

191

if (argv == NULL){

252

192

*argc = 1;

253

193

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

264

204

return NULL;

265

205

}

266

206

argv[*argc-1] = arg;

267

argv[*argc] = NULL;

207

argv[*argc] = NULL;

268

208

return argv;

269

209

}

270

210

271

static void free_plugin_list(plugin *plugin_list){

272

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

273

next = plugin_list->next;

274

for(char **arg = plugin_list->argv; *arg != NULL; arg++){

275

free(*arg);

276

}

277

free(plugin_list->argv);

278

for(char **env = plugin_list->environ; *env != NULL; env++){

279

free(*env);

280

}

281

free(plugin_list->environ);

282

free(plugin_list);

283

}

284

}

285

286

211

int main(int argc, char *argv[]){

287

const char *plugindir = "/lib/mandos/plugins.d";

288

const char *argfile = ARGFILE;

212

const char *plugindir = "/conf/conf.d/mandos/plugins.d";

213

const char *conffile = CONFFILE;

289

214

FILE *conffp;

290

215

size_t d_name_len;

291

216

DIR *dir = NULL;

306

231

/* Establish a signal handler */

307

232

sigemptyset(&sigchld_action.sa_mask);

308

233

ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);

309

if(ret == -1){

234

if(ret < 0){

310

235

perror("sigaddset");

311

exitstatus = EXIT_FAILURE;

312

goto fallback;

236

exit(EXIT_FAILURE);

313

237

}

314

238

ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);

315

if(ret == -1){

239

if(ret < 0){

316

240

perror("sigaction");

317

exitstatus = EXIT_FAILURE;

318

goto fallback;

241

exit(EXIT_FAILURE);

319

242

}

320

243

321

244

/* The options we understand. */

323

246

{ .name = "global-options", .key = 'g',

324

247

.arg = "OPTION[,OPTION[,...]]",

325

248

.doc = "Options passed to all plugins" },

326

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

327

.arg = "VAR=value",

328

.doc = "Environment variable passed to all plugins" },

329

249

{ .name = "options-for", .key = 'o',

330

250

.arg = "PLUGIN:OPTION[,OPTION[,...]]",

331

251

.doc = "Options passed only to specified plugin" },

332

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

333

.arg = "PLUGIN:ENV=value",

334

.doc = "Environment variable passed to specified plugin" },

335

252

{ .name = "disable", .key = 'd',

336

253

.arg = "PLUGIN",

337

254

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

361

278

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

362

279

continue;

363

280

}

364

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

365

perror("add_argument");

366

return ARGP_ERR_UNKNOWN;

367

}

368

}

369

}

370

break;

371

case 'e':

372

if(arg == NULL){

373

break;

374

}

375

{

376

char *envdef = strdup(arg);

377

if(envdef == NULL){

378

break;

379

}

380

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

381

perror("add_environment");

281

addargument(getplugin(NULL, plugins), p);

382

282

}

383

283

}

384

284

break;

385

285

case 'o':

386

286

if (arg != NULL){

387

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

388

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

287

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

288

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

389

289

break;

390

290

}

391

291

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

398

298

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

399

299

continue;

400

300

}

401

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

402

perror("add_argument");

403

return ARGP_ERR_UNKNOWN;

404

}

301

addargument(getplugin(name, plugins), p);

405

302

}

406

303

}

407

304

}

408

305

break;

409

case 'f':

410

if(arg == NULL){

411

break;

412

}

413

{

414

char *envdef = strchr(arg, ':');

415

if(envdef == NULL){

416

break;

417

}

418

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

419

if(p_name == NULL){

420

break;

421

}

422

envdef++;

423

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

424

perror("add_environment");

425

}

426

}

427

break;

428

306

case 'd':

429

307

if (arg != NULL){

430

plugin *p = getplugin(arg, plugins);

431

if(p == NULL){

432

return ARGP_ERR_UNKNOWN;

433

}

434

p->disabled = true;

308

getplugin(arg, plugins)->disabled = true;

435

309

}

436

310

break;

437

311

case 128:

447

321

debug = true;

448

322

break;

449

323

case ARGP_KEY_ARG:

450

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

324

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

451

325

break;

452

326

case ARGP_KEY_END:

453

327

break;

467

341

if (ret == ARGP_ERR_UNKNOWN){

468

342

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

469

343

exitstatus = EXIT_FAILURE;

470

goto fallback;

344

goto end;

471

345

}

472

346

473

conffp = fopen(argfile, "r");

347

conffp = fopen(conffile, "r");

474

348

if(conffp != NULL){

475

349

char *org_line = NULL;

476

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

477

350

size_t size = 0;

478

351

ssize_t sret;

352

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

479

353

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

480

354

const char comment_delim[] = "#";

481

355

492

366

continue;

493

367

}

494

368

new_arg = strdup(p);

495

custom_argv = add_to_argv(custom_argv, &custom_argc, new_arg);

369

custom_argv = addcustomargument(custom_argv, &custom_argc, new_arg);

496

370

if (custom_argv == NULL){

497

perror("add_to_argv");

371

perror("addcustomargument");

498

372

exitstatus = EXIT_FAILURE;

499

goto fallback;

373

goto end;

500

374

}

501

375

}

502

376

}

503

377

free(org_line);

504

378

} else{

505

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

506

not affect opening plugins */

379

/* check for harmfull errors */

507

380

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

508

381

perror("fopen");

509

382

exitstatus = EXIT_FAILURE;

510

goto fallback;

383

goto end;

511

384

}

512

385

}

513

386

517

390

if (ret == ARGP_ERR_UNKNOWN){

518

391

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

519

392

exitstatus = EXIT_FAILURE;

520

goto fallback;

393

goto end;

521

394

}

522

395

}

523

396

528

401

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

529

402

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

530

403

}

531

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

532

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

533

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

534

}

535

404

}

536

405

}

537

406

549

418

if(dir == NULL){

550

419

perror("Could not open plugin dir");

551

420

exitstatus = EXIT_FAILURE;

552

goto fallback;

421

goto end;

553

422

}

554

423

555

424

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

560

429

if(ret < 0){

561

430

perror("set_cloexec_flag");

562

431

exitstatus = EXIT_FAILURE;

563

goto fallback;

432

goto end;

564

433

}

565

434

}

566

435

}

575

444

if (errno == EBADF){

576

445

perror("readdir");

577

446

exitstatus = EXIT_FAILURE;

578

goto fallback;

447

goto end;

579

448

}

580

449

break;

581

450

}

626

495

continue;

627

496

}

628

497

}

629

630

char *filename;

631

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

632

if(ret < 0){

633

perror("asprintf");

498

499

char *filename = malloc(d_name_len + strlen(plugindir) + 2);

500

if (filename == NULL){

501

perror("malloc");

634

502

continue;

635

503

}

504

strcpy(filename, plugindir); /* Spurious warning */

505

strcat(filename, "/"); /* Spurious warning */

506

strcat(filename, dirst->d_name); /* Spurious warning */

636

507

637

508

ret = stat(filename, &st);

638

509

if (ret == -1){

649

520

free(filename);

650

521

continue;

651

522

}

652

plugin *p = getplugin(dirst->d_name, &plugin_list);

653

if(p == NULL){

654

perror("getplugin");

655

free(filename);

656

continue;

657

}

658

if(p->disabled){

523

if(getplugin(dirst->d_name, &plugin_list)->disabled){

659

524

if(debug){

660

525

fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",

661

526

dirst->d_name);

663

528

free(filename);

664

529

continue;

665

530

}

531

plugin *p = getplugin(dirst->d_name, &plugin_list);

666

532

{

667

533

/* Add global arguments to argument list for this plugin */

668

534

plugin *g = getplugin(NULL, &plugin_list);

669

if(g != NULL){

670

for(char **a = g->argv + 1; *a != NULL; a++){

671

if(not add_argument(p, *a)){

672

perror("add_argument");

673

}

674

}

675

/* Add global environment variables */

676

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

677

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

678

perror("add_environment");

679

}

680

}

681

}

682

}

683

/* If this plugin has any environment variables, we will call

684

using execve and need to duplicate the environment from this

685

process, too. */

686

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

687

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

688

char *copy = strdup(*e);

689

if(copy == NULL){

690

perror("strdup");

691

continue;

692

}

693

if(not add_environment(p, copy)){

694

perror("add_environment");

695

}

696

}

697

}

698

699

int pipefd[2];

535

for(char **a = g->argv + 1; *a != NULL; a++){

536

addargument(p, *a);

537

}

538

}

539

int pipefd[2];

700

540

ret = pipe(pipefd);

701

541

if (ret == -1){

702

542

perror("pipe");

703

543

exitstatus = EXIT_FAILURE;

704

goto fallback;

544

goto end;

705

545

}

706

546

ret = set_cloexec_flag(pipefd[0]);

707

547

if(ret < 0){

708

548

perror("set_cloexec_flag");

709

549

exitstatus = EXIT_FAILURE;

710

goto fallback;

550

goto end;

711

551

}

712

552

ret = set_cloexec_flag(pipefd[1]);

713

553

if(ret < 0){

714

554

perror("set_cloexec_flag");

715

555

exitstatus = EXIT_FAILURE;

716

goto fallback;

556

goto end;

717

557

}

718

558

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

719

559

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

720

560

if(ret < 0){

721

561

perror("sigprocmask");

722

562

exitstatus = EXIT_FAILURE;

723

goto fallback;

563

goto end;

724

564

}

725

565

// Starting a new process to be watched

726

566

pid_t pid = fork();

727

567

if(pid == -1){

728

568

perror("fork");

729

569

exitstatus = EXIT_FAILURE;

730

goto fallback;

570

goto end;

731

571

}

732

572

if(pid == 0){

733

573

/* this is the child process */

753

593

above and must now close it manually here. */

754

594

closedir(dir);

755

595

}

756

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

757

if(execv(filename, p->argv) < 0){

758

perror("execv");

759

_exit(EXIT_FAILURE);

760

}

761

} else {

762

if(execve(filename, p->argv, p->environ) < 0){

763

perror("execve");

764

_exit(EXIT_FAILURE);

765

}

596

if(execv(filename, p->argv) < 0){

597

perror("execv");

598

_exit(EXIT_FAILURE);

766

599

}

767

600

/* no return */

768

601

}

777

610

perror("sigprocmask");

778

611

}

779

612

exitstatus = EXIT_FAILURE;

780

goto fallback;

613

goto end;

781

614

}

782

615

783

616

*new_process = (struct process){ .pid = pid,

791

624

if(ret < 0){

792

625

perror("sigprocmask");

793

626

exitstatus = EXIT_FAILURE;

794

goto fallback;

627

goto end;

795

628

}

796

629

797

630

FD_SET(new_process->fd, &rfds_all);

802

635

803

636

}

804

637

805

free_plugin_list(plugin_list);

806

plugin_list = NULL;

638

/* Free the plugin list */

639

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

640

next = plugin_list->next;

641

free(plugin_list->argv);

642

free(plugin_list);

643

}

807

644

808

645

closedir(dir);

809

646

dir = NULL;

819

656

if (select_ret == -1){

820

657

perror("select");

821

658

exitstatus = EXIT_FAILURE;

822

goto fallback;

659

goto end;

823

660

}

824

661

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

825

662

from one of them */

847

684

/* Remove the plugin */

848

685

FD_CLR(proc->fd, &rfds_all);

849

686

/* Block signal while modifying process_list */

850

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

687

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

851

688

if(ret < 0){

852

689

perror("sigprocmask");

853

690

exitstatus = EXIT_FAILURE;

854

goto fallback;

691

goto end;

855

692

}

856

693

/* Delete this process entry from the list */

857

694

if(process_list == proc){

881

718

}

882

719

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

883

720

884

bool bret = print_out_password(proc->buffer,

885

proc->buffer_length);

721

bool bret = print_out_password(proc->buffer, proc->buffer_length);

886

722

if(not bret){

887

723

perror("print_out_password");

888

724

exitstatus = EXIT_FAILURE;

889

725

}

890

goto fallback;

726

goto end;

891

727

}

892

728

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

893

729

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

901

737

if (proc->buffer == NULL){

902

738

perror("malloc");

903

739

exitstatus = EXIT_FAILURE;

904

goto fallback;

740

goto end;

905

741

}

906

742

proc->buffer_size += BUFFER_SIZE;

907

743

}

922

758

}

923

759

924

760

925

fallback:

761

end:

926

762

927

763

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

928

/* Fallback if all plugins failed, none are found or an error

929

occured */

764

/* Fallback if all plugins failed, none are found or an error occured */

930

765

bool bret;

931

766

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

932

767

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

934

769

if(not bret){

935

770

perror("print_out_password");

936

771

exitstatus = EXIT_FAILURE;

772

goto end;

937

773

}

938

774

}

939

775

940

776

/* Restore old signal handler */

941

ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);

942

if(ret == -1){

943

perror("sigaction");

944

exitstatus = EXIT_FAILURE;

945

}

946

947

if(custom_argv != NULL){

948

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

949

free(*arg);

950

}

951

free(custom_argv);

952

}

953

free_plugin_list(plugin_list);

777

sigaction(SIGCHLD, &old_sigchld_action, NULL);

778

779

free(custom_argv);

780

781

/* Free the plugin list */

782

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

783

next = plugin_list->next;

784

free(plugin_list->argv);

785

free(plugin_list);

786

}

954

787

955

788

if(dir != NULL){

956

789

closedir(dir);