/mandos/trunk : revision 24.1.50

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,

64

65

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

65

66

67

#define BUFFER_SIZE 256

67

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

68

69

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

69

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

70

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

71

72

struct process;

87

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

88

char **argv;

89

int argc;

90

char **environ;

91

int envc;

92

90

bool disabled;

93

91

struct plugin *next;

94

92

} plugin;

103

101

/* Create a new plugin */

104

102

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

105

103

if (new_plugin == NULL){

106

return NULL;

107

}

108

char *copy_name = NULL;

109

if(name != NULL){

110

copy_name = strdup(name);

111

if(copy_name == NULL){

112

return NULL;

113

}

114

}

115

116

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

117

.argc = 1,

118

.envc = 0,

119

.disabled = false,

120

.next = *plugin_list };

121

104

perror("malloc");

105

exit(EXIT_FAILURE);

106

}

107

new_plugin->name = name;

122

108

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

123

109

if (new_plugin->argv == NULL){

124

free(copy_name);

125

free(new_plugin);

126

return NULL;

110

perror("malloc");

111

exit(EXIT_FAILURE);

127

112

}

128

new_plugin->argv[0] = copy_name;

113

new_plugin->argv[0] = name;

129

114

new_plugin->argv[1] = NULL;

130

131

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

132

if(new_plugin->environ == NULL){

133

free(copy_name);

134

free(new_plugin->argv);

135

free(new_plugin);

136

return NULL;

137

}

138

new_plugin->environ[0] = NULL;

115

new_plugin->argc = 1;

116

new_plugin->disabled = false;

117

new_plugin->next = *plugin_list;

139

118

/* Append the new plugin to the list */

140

119

*plugin_list = new_plugin;

141

120

return new_plugin;

142

121

}

143

122

144

/* Helper function for add_argument and add_environment */

145

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

146

int *len){

147

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

148

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

149

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

150

/* Malloc check */

151

if(*array == NULL){

152

return false;

153

}

154

/* Make a copy of the new string */

155

char *copy = strdup(new);

156

if(copy == NULL){

157

return false;

158

}

159

/* Insert the copy */

160

(*array)[*len] = copy;

161

(*len)++;

162

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

163

(*array)[*len] = NULL;

164

return true;

165

}

166

167

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

168

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

169

if(p == NULL){

170

return false;

171

}

172

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

173

}

174

175

/* Add to a plugin's environment */

176

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

177

if(p == NULL){

178

return false;

179

}

180

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

181

}

182

123

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

124

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

125

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

126

if (p->argv == NULL){

127

perror("malloc");

128

exit(EXIT_FAILURE);

129

}

130

p->argc++;

131

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

132

}

183

133

184

134

/*

185

135

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

199

149

200

150

process *process_list = NULL;

201

151

202

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

152

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

203

153

status. */

204

154

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

205

155

process *proc = process_list;

206

while(true){

207

int status;

208

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

209

if(pid == 0){

210

break;

211

}

212

if(pid == -1){

213

if (errno != ECHILD){

214

perror("waitpid");

215

}

216

return;

217

}

218

219

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

220

proc = proc->next;

221

}

222

if(proc == NULL){

223

/* Process not found in process list */

224

continue;

225

}

226

proc->status = status;

227

proc->completed = true;

228

}

156

int status;

157

pid_t pid = wait(&status);

158

if(pid == -1){

159

perror("wait");

160

return;

161

}

162

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

163

proc = proc->next;

164

}

165

if(proc == NULL){

166

/* Process not found in process list */

167

return;

168

}

169

proc->status = status;

170

proc->completed = true;

229

171

}

230

172

231

173

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

243

185

return true;

244

186

}

245

187

246

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

247

if (argv == NULL){

248

*argc = 1;

249

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

250

if(argv == NULL){

251

return NULL;

252

}

253

argv[0] = NULL; /* Will be set to argv[0] in main before parsing */

254

argv[1] = NULL;

255

}

256

*argc += 1;

257

argv = realloc(argv, sizeof(char *)

258

* ((unsigned int) *argc + 1));

259

if(argv == NULL){

260

return NULL;

261

}

262

argv[*argc-1] = arg;

263

argv[*argc] = NULL;

264

return argv;

265

}

266

267

static void free_plugin_list(plugin *plugin_list){

268

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

269

next = plugin_list->next;

270

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

271

free(*arg);

272

}

273

free(plugin_list->argv);

274

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

275

free(*env);

276

}

277

free(plugin_list->environ);

278

free(plugin_list);

279

}

280

}

281

282

188

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

283

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

284

const char *argfile = ARGFILE;

285

FILE *conffp;

189

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

286

190

size_t d_name_len;

287

191

DIR *dir = NULL;

288

192

struct dirent *dirst;

296

200

struct sigaction old_sigchld_action;

297

201

struct sigaction sigchld_action = { .sa_handler = handle_sigchld,

298

202

.sa_flags = SA_NOCLDSTOP };

299

char **custom_argv = NULL;

300

int custom_argc = 0;

301

203

char *plus_options = NULL;

204

char **plus_argv = NULL;

205

302

206

/* Establish a signal handler */

303

207

sigemptyset(&sigchld_action.sa_mask);

304

208

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

305

if(ret == -1){

209

if(ret < 0){

306

210

perror("sigaddset");

307

exitstatus = EXIT_FAILURE;

308

goto fallback;

211

exit(EXIT_FAILURE);

309

212

}

310

213

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

311

if(ret == -1){

214

if(ret < 0){

312

215

perror("sigaction");

313

exitstatus = EXIT_FAILURE;

314

goto fallback;

216

exit(EXIT_FAILURE);

315

217

}

316

218

317

219

/* The options we understand. */

319

221

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

320

222

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

321

223

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

322

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

323

.arg = "VAR=value",

324

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

325

224

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

326

225

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

327

226

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

328

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

329

.arg = "PLUGIN:ENV=value",

330

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

331

227

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

332

228

.arg = "PLUGIN",

333

229

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

354

250

if (arg != NULL){

355

251

char *p;

356

252

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

357

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

253

if(strcmp(p, "") == 0){

358

254

continue;

359

255

}

360

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

361

perror("add_argument");

362

return ARGP_ERR_UNKNOWN;

363

}

364

}

365

}

366

break;

367

case 'e':

368

if(arg == NULL){

369

break;

370

}

371

{

372

char *envdef = strdup(arg);

373

if(envdef == NULL){

374

break;

375

}

376

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

377

perror("add_environment");

256

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

378

257

}

379

258

}

380

259

break;

381

260

case 'o':

382

261

if (arg != NULL){

383

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

384

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

262

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

263

if(strcmp(name, "") == 0){

385

264

break;

386

265

}

387

266

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

388

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

267

if(strcmp(opt, "") == 0){

389

268

break;

390

269

}

391

270

if(opt != NULL){

392

271

char *p;

393

272

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

394

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

273

if(strcmp(p, "") == 0){

395

274

continue;

396

275

}

397

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

398

perror("add_argument");

399

return ARGP_ERR_UNKNOWN;

400

}

276

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

401

277

}

402

278

}

403

279

}

404

280

break;

405

case 'f':

406

if(arg == NULL){

407

break;

408

}

409

{

410

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

411

if(envdef == NULL){

412

break;

413

}

414

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

415

if(p_name == NULL){

416

break;

417

}

418

envdef++;

419

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

420

perror("add_environment");

421

}

422

}

423

break;

424

281

case 'd':

425

282

if (arg != NULL){

426

plugin *p = getplugin(arg, plugins);

427

if(p == NULL){

428

return ARGP_ERR_UNKNOWN;

429

}

430

p->disabled = true;

283

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

431

284

}

432

285

break;

433

286

case 128:

443

296

debug = true;

444

297

break;

445

298

case ARGP_KEY_ARG:

446

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

299

if(plus_options != NULL or arg == NULL or arg[0] != '+'){

300

argp_usage (state);

301

}

302

plus_options = arg;

447

303

break;

448

304

case ARGP_KEY_END:

449

305

break;

463

319

if (ret == ARGP_ERR_UNKNOWN){

464

320

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

465

321

exitstatus = EXIT_FAILURE;

466

goto fallback;

322

goto end;

467

323

}

468

469

conffp = fopen(argfile, "r");

470

if(conffp != NULL){

471

char *org_line = NULL;

472

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

473

size_t size = 0;

474

ssize_t sret;

475

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

476

const char comment_delim[] = "#";

477

478

while(true){

479

sret = getline(&org_line, &size, conffp);

480

if(sret == -1){

481

break;

482

}

483

484

line = org_line;

485

arg = strsep(&line, comment_delim);

486

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

487

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

488

continue;

489

}

490

new_arg = strdup(p);

491

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

492

if (custom_argv == NULL){

493

perror("add_to_argv");

494

exitstatus = EXIT_FAILURE;

495

goto fallback;

496

}

497

}

498

}

499

free(org_line);

500

} else{

501

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

502

not affect opening plugins */

503

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

504

perror("fopen");

324

325

if(plus_options){

326

/* This is a mangled argument in the form of

327

"+--option+--other-option=parameter+--yet-another-option", etc */

328

/* Make new argc and argv vars, and call argp_parse() again. */

329

plus_options++; /* skip the first '+' character */

330

const char delims[] = "+";

331

char *arg;

332

int new_argc = 1;

333

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

334

if(plus_argv == NULL){

335

perror("malloc");

505

336

exitstatus = EXIT_FAILURE;

506

goto fallback;

507

}

508

}

509

510

if(custom_argv != NULL){

511

custom_argv[0] = argv[0];

512

ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);

337

goto end;

338

}

339

plus_argv[0] = argv[0];

340

plus_argv[1] = NULL;

341

342

while((arg = strsep(&plus_options, delims)) != NULL){

343

new_argc++;

344

plus_argv = realloc(plus_argv, sizeof(char *)

345

* ((unsigned int) new_argc + 1));

346

if(plus_argv == NULL){

347

perror("realloc");

348

exitstatus = EXIT_FAILURE;

349

goto end;

350

}

351

plus_argv[new_argc-1] = arg;

352

plus_argv[new_argc] = NULL;

353

}

354

355

ret = argp_parse (&argp, new_argc, plus_argv, 0, 0, &plugin_list);

513

356

if (ret == ARGP_ERR_UNKNOWN){

514

357

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

515

358

exitstatus = EXIT_FAILURE;

516

goto fallback;

359

goto end;

517

360

}

518

361

}

519

362

524

367

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

525

368

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

526

369

}

527

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

528

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

529

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

530

}

531

370

}

532

371

}

533

372

545

384

if(dir == NULL){

546

385

perror("Could not open plugin dir");

547

386

exitstatus = EXIT_FAILURE;

548

goto fallback;

387

goto end;

549

388

}

550

389

551

390

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

556

395

if(ret < 0){

557

396

perror("set_cloexec_flag");

558

397

exitstatus = EXIT_FAILURE;

559

goto fallback;

398

goto end;

560

399

}

561

400

}

562

401

}

571

410

if (errno == EBADF){

572

411

perror("readdir");

573

412

exitstatus = EXIT_FAILURE;

574

goto fallback;

413

goto end;

575

414

}

576

415

break;

577

416

}

622

461

continue;

623

462

}

624

463

}

625

626

char *filename;

627

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

628

if(ret < 0){

629

perror("asprintf");

464

465

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

466

if (filename == NULL){

467

perror("malloc");

630

468

continue;

631

469

}

470

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

471

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

472

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

632

473

633

474

ret = stat(filename, &st);

634

475

if (ret == -1){

645

486

free(filename);

646

487

continue;

647

488

}

648

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

649

if(p == NULL){

650

perror("getplugin");

651

free(filename);

652

continue;

653

}

654

if(p->disabled){

489

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

655

490

if(debug){

656

491

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

657

492

dirst->d_name);

659

494

free(filename);

660

495

continue;

661

496

}

497

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

662

498

{

663

499

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

664

500

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

665

if(g != NULL){

666

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

667

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

668

perror("add_argument");

669

}

670

}

671

/* Add global environment variables */

672

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

673

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

674

perror("add_environment");

675

}

676

}

677

}

678

}

679

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

680

using execve and need to duplicate the environment from this

681

process, too. */

682

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

683

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

684

char *copy = strdup(*e);

685

if(copy == NULL){

686

perror("strdup");

687

continue;

688

}

689

if(not add_environment(p, copy)){

690

perror("add_environment");

691

}

692

}

693

}

694

695

int pipefd[2];

501

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

502

addargument(p, *a);

503

}

504

}

505

int pipefd[2];

696

506

ret = pipe(pipefd);

697

507

if (ret == -1){

698

508

perror("pipe");

699

509

exitstatus = EXIT_FAILURE;

700

goto fallback;

510

goto end;

701

511

}

702

512

ret = set_cloexec_flag(pipefd[0]);

703

513

if(ret < 0){

704

514

perror("set_cloexec_flag");

705

515

exitstatus = EXIT_FAILURE;

706

goto fallback;

516

goto end;

707

517

}

708

518

ret = set_cloexec_flag(pipefd[1]);

709

519

if(ret < 0){

710

520

perror("set_cloexec_flag");

711

521

exitstatus = EXIT_FAILURE;

712

goto fallback;

522

goto end;

713

523

}

714

524

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

715

525

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

716

526

if(ret < 0){

717

527

perror("sigprocmask");

718

528

exitstatus = EXIT_FAILURE;

719

goto fallback;

529

goto end;

720

530

}

721

531

// Starting a new process to be watched

722

532

pid_t pid = fork();

723

533

if(pid == -1){

724

534

perror("fork");

725

535

exitstatus = EXIT_FAILURE;

726

goto fallback;

536

goto end;

727

537

}

728

538

if(pid == 0){

729

539

/* this is the child process */

749

559

above and must now close it manually here. */

750

560

closedir(dir);

751

561

}

752

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

753

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

754

perror("execv");

755

_exit(EXIT_FAILURE);

756

}

757

} else {

758

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

759

perror("execve");

760

_exit(EXIT_FAILURE);

761

}

562

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

563

perror("execv");

564

_exit(EXIT_FAILURE);

762

565

}

763

566

/* no return */

764

567

}

773

576

perror("sigprocmask");

774

577

}

775

578

exitstatus = EXIT_FAILURE;

776

goto fallback;

579

goto end;

777

580

}

778

581

779

582

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

787

590

if(ret < 0){

788

591

perror("sigprocmask");

789

592

exitstatus = EXIT_FAILURE;

790

goto fallback;

593

goto end;

791

594

}

792

595

793

596

FD_SET(new_process->fd, &rfds_all);

798

601

799

602

}

800

603

801

free_plugin_list(plugin_list);

802

plugin_list = NULL;

604

/* Free the plugin list */

605

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

606

next = plugin_list->next;

607

free(plugin_list->argv);

608

free(plugin_list);

609

}

803

610

804

611

closedir(dir);

805

612

dir = NULL;

815

622

if (select_ret == -1){

816

623

perror("select");

817

624

exitstatus = EXIT_FAILURE;

818

goto fallback;

625

goto end;

819

626

}

820

627

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

821

628

from one of them */

847

654

if(ret < 0){

848

655

perror("sigprocmask");

849

656

exitstatus = EXIT_FAILURE;

850

goto fallback;

657

goto end;

851

658

}

852

659

/* Delete this process entry from the list */

853

660

if(process_list == proc){

882

689

perror("print_out_password");

883

690

exitstatus = EXIT_FAILURE;

884

691

}

885

goto fallback;

692

goto end;

886

693

}

887

694

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

888

695

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

896

703

if (proc->buffer == NULL){

897

704

perror("malloc");

898

705

exitstatus = EXIT_FAILURE;

899

goto fallback;

706

goto end;

900

707

}

901

708

proc->buffer_size += BUFFER_SIZE;

902

709

}

917

724

}

918

725

919

726

920

fallback:

727

end:

921

728

922

729

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

923

730

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

928

735

if(not bret){

929

736

perror("print_out_password");

930

737

exitstatus = EXIT_FAILURE;

738

goto end;

931

739

}

932

740

}

933

741

934

742

/* Restore old signal handler */

935

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

936

if(ret == -1){

937

perror("sigaction");

938

exitstatus = EXIT_FAILURE;

939

}

940

941

if(custom_argv != NULL){

942

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

943

free(*arg);

944

}

945

free(custom_argv);

946

}

947

free_plugin_list(plugin_list);

743

sigaction(SIGCHLD, &old_sigchld_action, NULL);

744

745

free(plus_argv);

746

747

/* Free the plugin list */

748

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

749

next = plugin_list->next;

750

free(plugin_list->argv);

751

free(plugin_list);

752

}

948

753

949

754

if(dir != NULL){

950

755

closedir(dir);