/mandos/release : revision 68

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> /* strtok, 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

235

185

return true;

236

186

}

237

187

238

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

239

if (argv == NULL){

240

*argc = 1;

241

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

242

if(argv == NULL){

243

return NULL;

244

}

245

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

246

argv[1] = NULL;

247

}

248

*argc += 1;

249

argv = realloc(argv, sizeof(char *)

250

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

251

if(argv == NULL){

252

return NULL;

253

}

254

argv[*argc-1] = arg;

255

argv[*argc] = NULL;

256

return argv;

257

}

258

259

static void free_plugin_list(plugin *plugin_list){

260

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

261

next = plugin_list->next;

262

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

263

free(*arg);

264

}

265

free(plugin_list->argv);

266

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

267

free(*env);

268

}

269

free(plugin_list->environ);

270

free(plugin_list);

271

}

272

}

273

274

188

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

275

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

276

const char *argfile = ARGFILE;

277

FILE *conffp;

189

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

278

190

size_t d_name_len;

279

191

DIR *dir = NULL;

280

192

struct dirent *dirst;

288

200

struct sigaction old_sigchld_action;

289

201

struct sigaction sigchld_action = { .sa_handler = handle_sigchld,

290

202

.sa_flags = SA_NOCLDSTOP };

291

char **custom_argv = NULL;

292

int custom_argc = 0;

293

203

char *plus_options = NULL;

204

char **plus_argv = NULL;

205

294

206

/* Establish a signal handler */

295

207

sigemptyset(&sigchld_action.sa_mask);

296

208

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

297

if(ret == -1){

209

if(ret < 0){

298

210

perror("sigaddset");

299

exitstatus = EXIT_FAILURE;

300

goto fallback;

211

exit(EXIT_FAILURE);

301

212

}

302

213

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

303

if(ret == -1){

214

if(ret < 0){

304

215

perror("sigaction");

305

exitstatus = EXIT_FAILURE;

306

goto fallback;

216

exit(EXIT_FAILURE);

307

217

}

308

218

309

219

/* The options we understand. */

311

221

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

312

222

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

313

223

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

314

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

315

.arg = "VAR=value",

316

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

317

224

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

318

225

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

319

226

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

320

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

321

.arg = "PLUGIN:ENV=value",

322

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

323

227

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

324

228

.arg = "PLUGIN",

325

229

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

344

248

switch (key) {

345

249

case 'g':

346

250

if (arg != NULL){

347

char *p;

348

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

349

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

350

continue;

351

}

352

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

353

perror("add_argument");

354

return ARGP_ERR_UNKNOWN;

355

}

356

}

357

}

358

break;

359

case 'e':

360

if(arg == NULL){

361

break;

362

}

363

{

364

char *envdef = strdup(arg);

365

if(envdef == NULL){

366

break;

367

}

368

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

369

perror("add_environment");

370

}

251

char *p = strtok(arg, ",");

252

do{

253

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

254

p = strtok(NULL, ",");

255

} while (p != NULL);

371

256

}

372

257

break;

373

258

case 'o':

374

259

if (arg != NULL){

375

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

376

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

377

break;

378

}

379

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

380

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

381

break;

382

}

383

if(opt != NULL){

384

char *p;

385

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

386

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

387

continue;

388

}

389

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

390

perror("add_argument");

391

return ARGP_ERR_UNKNOWN;

392

}

393

}

394

}

395

}

396

break;

397

case 'f':

398

if(arg == NULL){

399

break;

400

}

401

{

402

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

403

if(envdef == NULL){

404

break;

405

}

406

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

407

if(p_name == NULL){

408

break;

409

}

410

envdef++;

411

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

412

perror("add_environment");

260

char *name = strtok(arg, ":");

261

char *p = strtok(NULL, ":");

262

if(p != NULL){

263

p = strtok(p, ",");

264

do{

265

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

266

p = strtok(NULL, ",");

267

} while (p != NULL);

413

268

}

414

269

}

415

270

break;

416

271

case 'd':

417

272

if (arg != NULL){

418

plugin *p = getplugin(arg, plugins);

419

if(p == NULL){

420

return ARGP_ERR_UNKNOWN;

421

}

422

p->disabled = true;

273

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

423

274

}

424

275

break;

425

276

case 128:

435

286

debug = true;

436

287

break;

437

288

case ARGP_KEY_ARG:

438

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

289

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

290

argp_usage (state);

291

}

292

plus_options = arg;

439

293

break;

440

294

case ARGP_KEY_END:

441

295

break;

455

309

if (ret == ARGP_ERR_UNKNOWN){

456

310

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

457

311

exitstatus = EXIT_FAILURE;

458

goto fallback;

312

goto end;

459

313

}

460

461

conffp = fopen(argfile, "r");

462

if(conffp != NULL){

463

char *org_line = NULL;

464

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

465

size_t size = 0;

466

ssize_t sret;

467

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

468

const char comment_delim[] = "#";

469

470

while(true){

471

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

472

if(sret == -1){

473

break;

474

}

475

476

line = org_line;

477

arg = strsep(&line, comment_delim);

478

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

479

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

480

continue;

481

}

482

new_arg = strdup(p);

483

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

484

if (custom_argv == NULL){

485

perror("add_to_argv");

486

exitstatus = EXIT_FAILURE;

487

goto fallback;

488

}

489

}

490

}

491

free(org_line);

492

} else{

493

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

494

not affect opening plugins */

495

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

496

perror("fopen");

314

315

if(plus_options){

316

/* This is a mangled argument in the form of

317

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

318

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

319

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

320

const char delims[] = "+";

321

char *arg;

322

int new_argc = 1;

323

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

324

if(plus_argv == NULL){

325

perror("malloc");

497

326

exitstatus = EXIT_FAILURE;

498

goto fallback;

499

}

500

}

501

502

if(custom_argv != NULL){

503

custom_argv[0] = argv[0];

504

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

327

goto end;

328

}

329

plus_argv[0] = argv[0];

330

plus_argv[1] = NULL;

331

arg = strtok(plus_options, delims); /* Get first argument */

332

while(arg != NULL){

333

new_argc++;

334

plus_argv = realloc(plus_argv, sizeof(char *)

335

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

336

if(plus_argv == NULL){

337

perror("realloc");

338

exitstatus = EXIT_FAILURE;

339

goto end;

340

}

341

plus_argv[new_argc-1] = arg;

342

plus_argv[new_argc] = NULL;

343

arg = strtok(NULL, delims); /* Get next argument */

344

}

345

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

505

346

if (ret == ARGP_ERR_UNKNOWN){

506

347

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

507

348

exitstatus = EXIT_FAILURE;

508

goto fallback;

349

goto end;

509

350

}

510

351

}

511

352

516

357

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

517

358

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

518

359

}

519

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

520

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

521

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

522

}

523

360

}

524

361

}

525

362

537

374

if(dir == NULL){

538

375

perror("Could not open plugin dir");

539

376

exitstatus = EXIT_FAILURE;

540

goto fallback;

377

goto end;

541

378

}

542

379

543

380

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

548

385

if(ret < 0){

549

386

perror("set_cloexec_flag");

550

387

exitstatus = EXIT_FAILURE;

551

goto fallback;

388

goto end;

552

389

}

553

390

}

554

391

}

563

400

if (errno == EBADF){

564

401

perror("readdir");

565

402

exitstatus = EXIT_FAILURE;

566

goto fallback;

403

goto end;

567

404

}

568

405

break;

569

406

}

614

451

continue;

615

452

}

616

453

}

617

618

char *filename;

619

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

620

if(ret < 0){

621

perror("asprintf");

622

continue;

454

455

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

456

if (filename == NULL){

457

perror("malloc");

458

exitstatus = EXIT_FAILURE;

459

goto end;

623

460

}

461

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

462

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

463

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

624

464

625

465

ret = stat(filename, &st);

626

466

if (ret == -1){

627

467

perror("stat");

628

free(filename);

629

continue;

468

exitstatus = EXIT_FAILURE;

469

goto end;

630

470

}

631

471

632

472

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

637

477

free(filename);

638

478

continue;

639

479

}

640

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

641

if(p == NULL){

642

perror("getplugin");

643

free(filename);

644

continue;

645

}

646

if(p->disabled){

480

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

647

481

if(debug){

648

482

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

649

483

dirst->d_name);

651

485

free(filename);

652

486

continue;

653

487

}

488

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

654

489

{

655

490

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

656

491

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

657

if(g != NULL){

658

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

659

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

660

perror("add_argument");

661

}

662

}

663

/* Add global environment variables */

664

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

665

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

666

perror("add_environment");

667

}

668

}

669

}

670

}

671

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

672

using execve and need to duplicate the environment from this

673

process, too. */

674

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

675

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

676

char *copy = strdup(*e);

677

if(copy == NULL){

678

perror("strdup");

679

continue;

680

}

681

if(not add_environment(p, copy)){

682

perror("add_environment");

683

}

684

}

685

}

686

687

int pipefd[2];

492

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

493

addargument(p, *a);

494

}

495

}

496

int pipefd[2];

688

497

ret = pipe(pipefd);

689

498

if (ret == -1){

690

499

perror("pipe");

691

500

exitstatus = EXIT_FAILURE;

692

goto fallback;

501

goto end;

693

502

}

694

503

ret = set_cloexec_flag(pipefd[0]);

695

504

if(ret < 0){

696

505

perror("set_cloexec_flag");

697

506

exitstatus = EXIT_FAILURE;

698

goto fallback;

507

goto end;

699

508

}

700

509

ret = set_cloexec_flag(pipefd[1]);

701

510

if(ret < 0){

702

511

perror("set_cloexec_flag");

703

512

exitstatus = EXIT_FAILURE;

704

goto fallback;

513

goto end;

705

514

}

706

515

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

707

516

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

708

517

if(ret < 0){

709

518

perror("sigprocmask");

710

519

exitstatus = EXIT_FAILURE;

711

goto fallback;

520

goto end;

712

521

}

713

522

// Starting a new process to be watched

714

523

pid_t pid = fork();

715

if(pid == -1){

716

perror("fork");

717

exitstatus = EXIT_FAILURE;

718

goto fallback;

719

}

720

524

if(pid == 0){

721

525

/* this is the child process */

722

526

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

741

545

above and must now close it manually here. */

742

546

closedir(dir);

743

547

}

744

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

745

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

746

perror("execv");

747

_exit(EXIT_FAILURE);

748

}

749

} else {

750

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

751

perror("execve");

752

_exit(EXIT_FAILURE);

753

}

548

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

549

perror("execv");

550

_exit(EXIT_FAILURE);

754

551

}

755

552

/* no return */

756

553

}

765

562

perror("sigprocmask");

766

563

}

767

564

exitstatus = EXIT_FAILURE;

768

goto fallback;

565

goto end;

769

566

}

770

567

771

568

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

779

576

if(ret < 0){

780

577

perror("sigprocmask");

781

578

exitstatus = EXIT_FAILURE;

782

goto fallback;

579

goto end;

783

580

}

784

581

785

582

FD_SET(new_process->fd, &rfds_all);

790

587

791

588

}

792

589

793

free_plugin_list(plugin_list);

794

plugin_list = NULL;

590

/* Free the plugin list */

591

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

592

next = plugin_list->next;

593

free(plugin_list->argv);

594

free(plugin_list);

595

}

795

596

796

597

closedir(dir);

797

598

dir = NULL;

807

608

if (select_ret == -1){

808

609

perror("select");

809

610

exitstatus = EXIT_FAILURE;

810

goto fallback;

611

goto end;

811

612

}

812

613

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

813

614

from one of them */

839

640

if(ret < 0){

840

641

perror("sigprocmask");

841

642

exitstatus = EXIT_FAILURE;

842

goto fallback;

643

goto end;

843

644

}

844

645

/* Delete this process entry from the list */

845

646

if(process_list == proc){

874

675

perror("print_out_password");

875

676

exitstatus = EXIT_FAILURE;

876

677

}

877

goto fallback;

678

goto end;

878

679

}

879

680

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

880

681

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

888

689

if (proc->buffer == NULL){

889

690

perror("malloc");

890

691

exitstatus = EXIT_FAILURE;

891

goto fallback;

692

goto end;

892

693

}

893

694

proc->buffer_size += BUFFER_SIZE;

894

695

}

909

710

}

910

711

911

712

912

fallback:

713

end:

913

714

914

715

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

915

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

716

/* Fallback if all plugins failed or an error occured */

916

717

bool bret;

917

718

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

918

719

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

920

721

if(not bret){

921

722

perror("print_out_password");

922

723

exitstatus = EXIT_FAILURE;

724

goto end;

923

725

}

924

726

}

925

727

926

728

/* Restore old signal handler */

927

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

928

if(ret == -1){

929

perror("sigaction");

930

exitstatus = EXIT_FAILURE;

931

}

932

933

if(custom_argv != NULL){

934

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

935

free(*arg);

936

}

937

free(custom_argv);

938

}

939

free_plugin_list(plugin_list);

729

sigaction(SIGCHLD, &old_sigchld_action, NULL);

730

731

free(plus_argv);

732

733

/* Free the plugin list */

734

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

735

next = plugin_list->next;

736

free(plugin_list->argv);

737

free(plugin_list);

738

}

940

739

941

740

if(dir != NULL){

942

741

closedir(dir);