/mandos/trunk : revision 65

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,

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.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

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/* Append the new plugin to the list */

130

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*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 */

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

139

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

140

/* Malloc check */

141

if(*array == NULL){

142

return false;

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}

144

/* Make a copy of the new string */

145

char *copy = strdup(new);

146

if(copy == NULL){

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return false;

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}

149

/* Insert the copy */

150

(*array)[*len] = copy;

151

(*len)++;

152

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

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(*array)[*len] = NULL;

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return true;

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}

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));

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}

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

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/*

175

135

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

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185

return true;

226

186

}

227

187

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;

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}

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

188

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

250

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

251

const char *argfile = ARGFILE;

252

FILE *conffp;

189

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

253

190

size_t d_name_len;

254

191

DIR *dir = NULL;

255

192

struct dirent *dirst;

263

200

struct sigaction old_sigchld_action;

264

201

struct sigaction sigchld_action = { .sa_handler = handle_sigchld,

265

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.sa_flags = SA_NOCLDSTOP };

266

char **custom_argv = NULL;

267

int custom_argc = 0;

203

char *plus_options = NULL;

204

char **plus_argv = NULL;

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/* Establish a signal handler */

270

207

sigemptyset(&sigchld_action.sa_mask);

284

221

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

285

222

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

286

223

.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

224

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

291

225

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

292

226

.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

227

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

297

228

.arg = "PLUGIN",

298

229

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

317

248

switch (key) {

318

249

case 'g':

319

250

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

}

251

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

252

do{

253

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

254

p = strtok(NULL, ",");

255

} while (p != NULL);

344

256

}

345

257

break;

346

258

case 'o':

347

259

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");

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);

386

268

}

387

269

}

388

270

break;

389

271

case 'd':

390

272

if (arg != NULL){

391

plugin *p = getplugin(arg, plugins);

392

if(p == NULL){

393

return ARGP_ERR_UNKNOWN;

394

}

395

p->disabled = true;

273

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

396

274

}

397

275

break;

398

276

case 128:

408

286

debug = true;

409

287

break;

410

288

case ARGP_KEY_ARG:

411

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;

412

293

break;

413

294

case ARGP_KEY_END:

414

295

break;

430

311

exitstatus = EXIT_FAILURE;

431

312

goto end;

432

313

}

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");

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");

470

326

exitstatus = EXIT_FAILURE;

471

327

goto end;

472

328

}

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);

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);

478

346

if (ret == ARGP_ERR_UNKNOWN){

479

347

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

480

348

exitstatus = EXIT_FAILURE;

489

357

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

490

358

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

491

359

}

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

360

}

497

361

}

498

362

587

451

continue;

588

452

}

589

453

}

590

591

char *filename;

592

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

593

if(ret < 0){

594

perror("asprintf");

595

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;

596

460

}

461

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

462

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

463

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

597

464

598

465

ret = stat(filename, &st);

599

466

if (ret == -1){

600

467

perror("stat");

601

free(filename);

602

continue;

468

exitstatus = EXIT_FAILURE;

469

goto end;

603

470

}

604

471

605

472

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

610

477

free(filename);

611

478

continue;

612

479

}

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){

480

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

620

481

if(debug){

621

482

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

622

483

dirst->d_name);

624

485

free(filename);

625

486

continue;

626

487

}

488

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

627

489

{

628

490

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

629

491

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

492

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

493

addargument(p, *a);

494

}

495

}

660

496

int pipefd[2];

661

497

ret = pipe(pipefd);

662

498

if (ret == -1){

685

521

}

686

522

// Starting a new process to be watched

687

523

pid_t pid = fork();

688

if(pid == -1){

689

perror("fork");

690

exitstatus = EXIT_FAILURE;

691

goto end;

692

}

693

524

if(pid == 0){

694

525

/* this is the child process */

695

526

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

714

545

above and must now close it manually here. */

715

546

closedir(dir);

716

547

}

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

}

548

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

549

perror("execv");

550

_exit(EXIT_FAILURE);

727

551

}

728

552

/* no return */

729

553

}

767

591

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

768

592

next = plugin_list->next;

769

593

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

594

free(plugin_list);

776

595

}

777

596

889

708

}

890

709

}

891

710

}

892

893

894

end:

895

711

896

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

897

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

712

if(process_list == NULL){

898

713

bool bret;

899

714

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

900

715

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

905

720

goto end;

906

721

}

907

722

}

723

724

end:

908

725

909

726

/* Restore old signal handler */

910

727

sigaction(SIGCHLD, &old_sigchld_action, NULL);

911

728

912

free(custom_argv);

729

free(plus_argv);

913

730

914

731

/* Free the plugin list */

915

732

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

916

733

next = plugin_list->next;

917

734

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

735

free(plugin_list);

925

736

}

926

737