/mandos/trunk : revision 62

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;

104

perror("malloc");

105

exit(EXIT_FAILURE);

107

106

}

108

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

109

.argc = 1,

110

.envc = 0,

111

.disabled = false,

112

.next = *plugin_list };

113

107

new_plugin->name = name;

114

108

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

115

109

if (new_plugin->argv == NULL){

116

free(new_plugin);

117

return NULL;

110

perror("malloc");

111

exit(EXIT_FAILURE);

118

112

}

119

113

new_plugin->argv[0] = name;

120

114

new_plugin->argv[1] = NULL;

121

122

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

123

if(new_plugin->environ == NULL){

124

free(new_plugin->argv);

125

free(new_plugin);

126

return NULL;

127

}

128

new_plugin->environ[0] = NULL;

115

new_plugin->argc = 1;

116

new_plugin->disabled = false;

117

new_plugin->next = *plugin_list;

129

118

/* Append the new plugin to the list */

130

119

*plugin_list = new_plugin;

131

120

return new_plugin;

132

121

}

133

122

134

/* Helper function for add_argument and add_environment */

135

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

136

int *len){

137

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

138

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

139

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

140

/* Malloc check */

141

if(*array == NULL){

142

return false;

143

}

144

/* Make a copy of the new string */

145

char *copy = strdup(new);

146

if(copy == NULL){

147

return false;

148

}

149

/* Insert the copy */

150

(*array)[*len] = copy;

151

(*len)++;

152

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

153

(*array)[*len] = NULL;

154

return true;

155

}

156

157

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

158

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

159

if(p == NULL){

160

return false;

161

}

162

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

163

}

164

165

/* Add to a plugin's environment */

166

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

167

if(p == NULL){

168

return false;

169

}

170

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

171

}

172

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

}

173

133

174

134

/*

175

135

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

210

170

proc->completed = true;

211

171

}

212

172

213

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

214

ssize_t ret;

215

if(length>0 and buffer[length-1] == '\n'){

216

length--;

217

}

218

for(size_t written = 0; written < length; written += (size_t)ret){

219

ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,

220

length - written));

221

if(ret < 0){

222

return false;

223

}

224

}

225

return true;

226

}

227

228

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

229

if (argv == NULL){

230

*argc = 1;

231

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

232

if(argv == NULL){

233

return NULL;

234

}

235

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

236

argv[1] = NULL;

237

}

238

*argc += 1;

239

argv = realloc(argv, sizeof(char *)

240

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

241

if(argv == NULL){

242

return NULL;

243

}

244

argv[*argc-1] = arg;

245

argv[*argc] = NULL;

246

return argv;

247

}

248

249

173

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

250

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

251

const char *argfile = ARGFILE;

252

FILE *conffp;

174

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

253

175

size_t d_name_len;

254

176

DIR *dir = NULL;

255

177

struct dirent *dirst;

263

185

struct sigaction old_sigchld_action;

264

186

struct sigaction sigchld_action = { .sa_handler = handle_sigchld,

265

187

.sa_flags = SA_NOCLDSTOP };

266

char **custom_argv = NULL;

267

int custom_argc = 0;

188

char *plus_options = NULL;

189

char **plus_argv = NULL;

268

190

269

191

/* Establish a signal handler */

270

192

sigemptyset(&sigchld_action.sa_mask);

284

206

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

285

207

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

286

208

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

287

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

288

.arg = "VAR=value",

289

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

290

209

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

291

210

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

292

211

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

293

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

294

.arg = "PLUGIN:ENV=value",

295

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

296

212

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

297

213

.arg = "PLUGIN",

298

214

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

317

233

switch (key) {

318

234

case 'g':

319

235

if (arg != NULL){

320

char *p;

321

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

322

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

323

continue;

324

}

325

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

326

perror("add_argument");

327

return ARGP_ERR_UNKNOWN;

328

}

329

}

330

}

331

break;

332

case 'e':

333

if(arg == NULL){

334

break;

335

}

336

{

337

char *envdef = strdup(arg);

338

if(envdef == NULL){

339

break;

340

}

341

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

342

perror("add_environment");

343

}

236

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

237

do{

238

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

239

p = strtok(NULL, ",");

240

} while (p != NULL);

344

241

}

345

242

break;

346

243

case 'o':

347

244

if (arg != NULL){

348

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

349

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

350

break;

351

}

352

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

353

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

354

break;

355

}

356

if(opt != NULL){

357

char *p;

358

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

359

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

360

continue;

361

}

362

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

363

perror("add_argument");

364

return ARGP_ERR_UNKNOWN;

365

}

366

}

367

}

368

}

369

break;

370

case 'f':

371

if(arg == NULL){

372

break;

373

}

374

{

375

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

376

if(envdef == NULL){

377

break;

378

}

379

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

380

if(p_name == NULL){

381

break;

382

}

383

envdef++;

384

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

385

perror("add_environment");

245

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

246

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

247

if(p != NULL){

248

p = strtok(p, ",");

249

do{

250

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

251

p = strtok(NULL, ",");

252

} while (p != NULL);

386

253

}

387

254

}

388

255

break;

389

256

case 'd':

390

257

if (arg != NULL){

391

plugin *p = getplugin(arg, plugins);

392

if(p == NULL){

393

return ARGP_ERR_UNKNOWN;

394

}

395

p->disabled = true;

258

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

396

259

}

397

260

break;

398

261

case 128:

408

271

debug = true;

409

272

break;

410

273

case ARGP_KEY_ARG:

411

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

274

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

275

argp_usage (state);

276

}

277

plus_options = arg;

412

278

break;

413

279

case ARGP_KEY_END:

414

280

break;

426

292

427

293

ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);

428

294

if (ret == ARGP_ERR_UNKNOWN){

429

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

295

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

430

296

exitstatus = EXIT_FAILURE;

431

297

goto end;

432

298

}

433

434

conffp = fopen(argfile, "r");

435

if(conffp != NULL){

436

char *org_line = NULL;

437

size_t size = 0;

438

ssize_t sret;

439

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

440

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

441

const char comment_delim[] = "#";

442

443

while(true){

444

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

445

if(sret == -1){

446

break;

447

}

448

449

line = org_line;

450

arg = strsep(&line, comment_delim);

451

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

452

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

453

continue;

454

}

455

new_arg = strdup(p);

456

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

457

if (custom_argv == NULL){

458

perror("add_to_argv");

459

exitstatus = EXIT_FAILURE;

460

goto end;

461

}

462

}

463

}

464

free(org_line);

465

} else{

466

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

467

not affect opening plugins */

468

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

469

perror("fopen");

299

300

if(plus_options){

301

/* This is a mangled argument in the form of

302

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

303

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

304

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

305

const char delims[] = "+";

306

char *arg;

307

int new_argc = 1;

308

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

309

if(plus_argv == NULL){

310

perror("malloc");

470

311

exitstatus = EXIT_FAILURE;

471

312

goto end;

472

313

}

473

}

474

475

if(custom_argv != NULL){

476

custom_argv[0] = argv[0];

477

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

314

plus_argv[0] = argv[0];

315

plus_argv[1] = NULL;

316

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

317

while(arg != NULL){

318

new_argc++;

319

plus_argv = realloc(plus_argv, sizeof(char *)

320

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

321

if(plus_argv == NULL){

322

perror("realloc");

323

exitstatus = EXIT_FAILURE;

324

goto end;

325

}

326

plus_argv[new_argc-1] = arg;

327

plus_argv[new_argc] = NULL;

328

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

329

}

330

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

478

331

if (ret == ARGP_ERR_UNKNOWN){

479

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

332

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

480

333

exitstatus = EXIT_FAILURE;

481

334

goto end;

482

335

}

489

342

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

490

343

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

491

344

}

492

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

493

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

494

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

495

}

496

345

}

497

346

}

498

347

587

436

continue;

588

437

}

589

438

}

590

591

char *filename;

592

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

593

if(ret < 0){

594

perror("asprintf");

595

continue;

439

440

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

441

if (filename == NULL){

442

perror("malloc");

443

exitstatus = EXIT_FAILURE;

444

goto end;

596

445

}

446

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

447

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

448

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

597

449

598

450

ret = stat(filename, &st);

599

451

if (ret == -1){

600

452

perror("stat");

601

free(filename);

602

continue;

453

exitstatus = EXIT_FAILURE;

454

goto end;

603

455

}

604

456

605

457

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

610

462

free(filename);

611

463

continue;

612

464

}

613

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

614

if(p == NULL){

615

perror("getplugin");

616

free(filename);

617

continue;

618

}

619

if(p->disabled){

465

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

620

466

if(debug){

621

467

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

622

468

dirst->d_name);

624

470

free(filename);

625

471

continue;

626

472

}

473

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

627

474

{

628

475

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

629

476

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

630

if(g != NULL){

631

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

632

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

633

perror("add_argument");

634

}

635

}

636

/* Add global environment variables */

637

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

638

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

639

perror("add_environment");

640

}

641

}

642

}

643

}

644

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

645

using execve and need to duplicate the environment from this

646

process, too. */

647

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

648

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

649

char *copy = strdup(*e);

650

if(copy == NULL){

651

perror("strdup");

652

continue;

653

}

654

if(not add_environment(p, copy)){

655

perror("add_environment");

656

}

657

}

658

}

659

477

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

478

addargument(p, *a);

479

}

480

}

660

481

int pipefd[2];

661

482

ret = pipe(pipefd);

662

483

if (ret == -1){

685

506

}

686

507

// Starting a new process to be watched

687

508

pid_t pid = fork();

688

if(pid == -1){

689

perror("fork");

690

exitstatus = EXIT_FAILURE;

691

goto end;

692

}

693

509

if(pid == 0){

694

510

/* this is the child process */

695

511

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

714

530

above and must now close it manually here. */

715

531

closedir(dir);

716

532

}

717

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

718

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

719

perror("execv");

720

_exit(EXIT_FAILURE);

721

}

722

} else {

723

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

724

perror("execve");

725

_exit(EXIT_FAILURE);

726

}

533

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

534

perror("execv");

535

_exit(EXIT_FAILURE);

727

536

}

728

537

/* no return */

729

538

}

767

576

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

768

577

next = plugin_list->next;

769

578

free(plugin_list->argv);

770

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

771

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

772

free(*e);

773

}

774

}

775

579

free(plugin_list);

776

580

}

777

581

779

583

dir = NULL;

780

584

781

585

if (process_list == NULL){

782

fprintf(stderr, "No plugin processes started. Incorrect plugin"

783

" directory?\n");

784

process_list = NULL;

586

fprintf(stderr, "No plugin processes started, exiting\n");

587

exitstatus = EXIT_FAILURE;

588

goto end;

785

589

}

786

590

while(process_list){

787

591

fd_set rfds = rfds_all;

850

654

break;

851

655

}

852

656

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

853

854

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

855

if(not bret){

856

perror("print_out_password");

857

exitstatus = EXIT_FAILURE;

657

for(size_t written = 0; written < proc->buffer_length;

658

written += (size_t)ret){

659

ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO,

660

proc->buffer + written,

661

proc->buffer_length

662

- written));

663

if(ret < 0){

664

perror("write");

665

exitstatus = EXIT_FAILURE;

666

goto end;

667

}

858

668

}

859

669

goto end;

860

670

}

889

699

}

890

700

}

891

701

}

892

893

702

if(process_list == NULL){

703

fprintf(stderr, "All plugin processes failed, exiting\n");

704

exitstatus = EXIT_FAILURE;

705

}

706

894

707

end:

895

896

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

897

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

898

bool bret;

899

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

900

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

901

bret = print_out_password(passwordbuffer, strlen(passwordbuffer));

902

if(not bret){

903

perror("print_out_password");

904

exitstatus = EXIT_FAILURE;

905

goto end;

906

}

907

}

908

909

708

/* Restore old signal handler */

910

709

sigaction(SIGCHLD, &old_sigchld_action, NULL);

911

710

912

free(custom_argv);

711

free(plus_argv);

913

712

914

713

/* Free the plugin list */

915

714

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

916

715

next = plugin_list->next;

917

716

free(plugin_list->argv);

918

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

919

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

920

free(*e);

921

}

922

}

923

free(plugin_list->environ);

924

717

free(plugin_list);

925

718

}

926

719