/mandos/release : revision 237.7.241

40

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

41

42

#include <stdio.h> /* fprintf(), stderr, fwrite(),

43

stdout, ferror() */

43

stdout, ferror(), remove() */

44

#include <stdint.h> /* uint16_t, uint32_t, intptr_t */

45

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

46

#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),

57

#include <sys/socket.h> /* socket(), struct sockaddr_in6,

58

inet_pton(), connect(),

59

getnameinfo() */

60

#include <fcntl.h> /* open(), unlinkat() */

60

#include <fcntl.h> /* open() */

61

#include <dirent.h> /* opendir(), struct dirent, readdir()

62

*/

63

#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,

73

*/

74

#include <unistd.h> /* close(), SEEK_SET, off_t, write(),

75

getuid(), getgid(), seteuid(),

76

setgid(), pause(), _exit(),

77

unlinkat() */

76

setgid(), pause(), _exit() */

78

77

#include <arpa/inet.h> /* inet_pton(), htons() */

79

78

#include <iso646.h> /* not, or, and */

80

79

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

234

233

.af = af };

235

234

if(new_server->ip == NULL){

236

235

perror_plus("strdup");

237

free(new_server);

238

236

return false;

239

237

}

240

238

ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));

241

239

if(ret == -1){

242

240

perror_plus("clock_gettime");

243

#ifdef __GNUC__

244

#pragma GCC diagnostic push

245

#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

free((char *)(new_server->ip));

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

241

return false;

253

242

}

254

243

/* Special case of first server */

493

482

return plaintext_length;

494

483

}

495

484

496

__attribute__((warn_unused_result, const))

497

static const char *safe_string(const char *str){

498

if(str == NULL)

499

return "(unknown)";

500

return str;

501

}

502

503

485

__attribute__((warn_unused_result))

504

486

static const char *safer_gnutls_strerror(int value){

505

487

const char *ret = gnutls_strerror(value);

506

return safe_string(ret);

488

if(ret == NULL)

489

ret = "(unknown)";

490

return ret;

507

491

}

508

492

509

493

/* GnuTLS log function callback */

518

502

const char *seckeyfilename,

519

503

mandos_context *mc){

520

504

int ret;

521

unsigned int uret;

522

505

523

506

if(debug){

524

507

fprintf_plus(stderr, "Initializing GnuTLS\n");

575

558

safer_gnutls_strerror(ret));

576

559

goto globalfail;

577

560

}

578

if(mc->dh_bits == 0){

579

/* Find out the optimal number of DH bits */

580

/* Try to read the private key file */

581

gnutls_datum_t buffer = { .data = NULL, .size = 0 };

582

{

583

int secfile = open(seckeyfilename, O_RDONLY);

584

size_t buffer_capacity = 0;

585

while(true){

586

buffer_capacity = incbuffer((char **)&buffer.data,

587

(size_t)buffer.size,

588

(size_t)buffer_capacity);

589

if(buffer_capacity == 0){

590

perror_plus("incbuffer");

591

free(buffer.data);

592

buffer.data = NULL;

593

break;

594

}

595

ssize_t bytes_read = read(secfile, buffer.data + buffer.size,

596

BUFFER_SIZE);

597

/* EOF */

598

if(bytes_read == 0){

599

break;

600

}

601

/* check bytes_read for failure */

602

if(bytes_read < 0){

603

perror_plus("read");

604

free(buffer.data);

605

buffer.data = NULL;

606

break;

607

}

608

buffer.size += (unsigned int)bytes_read;

609

}

610

close(secfile);

611

}

612

/* If successful, use buffer to parse private key */

613

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

614

if(buffer.data != NULL){

615

{

616

gnutls_openpgp_privkey_t privkey = NULL;

617

ret = gnutls_openpgp_privkey_init(&privkey);

618

if(ret != GNUTLS_E_SUCCESS){

619

fprintf_plus(stderr, "Error initializing OpenPGP key"

620

" structure: %s", safer_gnutls_strerror(ret));

621

free(buffer.data);

622

buffer.data = NULL;

623

} else {

624

ret = gnutls_openpgp_privkey_import(privkey, &buffer,

625

GNUTLS_OPENPGP_FMT_BASE64,

626

"", 0);

627

if(ret != GNUTLS_E_SUCCESS){

628

fprintf_plus(stderr, "Error importing OpenPGP key : %s",

629

safer_gnutls_strerror(ret));

630

privkey = NULL;

631

}

632

free(buffer.data);

633

buffer.data = NULL;

634

if(privkey != NULL){

635

/* Use private key to suggest an appropriate sec_param */

636

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

637

gnutls_openpgp_privkey_deinit(privkey);

638

if(debug){

639

fprintf_plus(stderr, "This OpenPGP key implies using a"

640

" GnuTLS security parameter \"%s\".\n",

641

safe_string(gnutls_sec_param_get_name

642

(sec_param)));

643

}

644

}

645

}

646

}

647

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

648

/* Err on the side of caution */

649

sec_param = GNUTLS_SEC_PARAM_ULTRA;

650

if(debug){

651

fprintf_plus(stderr, "Falling back to security parameter"

652

" \"%s\"\n",

653

safe_string(gnutls_sec_param_get_name

654

(sec_param)));

655

}

656

}

657

}

658

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

659

if(uret != 0){

660

mc->dh_bits = uret;

661

if(debug){

662

fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"

663

" implies %u DH bits; using that.\n",

664

safe_string(gnutls_sec_param_get_name

665

(sec_param)),

666

mc->dh_bits);

667

}

668

} else {

669

fprintf_plus(stderr, "Failed to get implied number of DH"

670

" bits for security parameter \"%s\"): %s\n",

671

safe_string(gnutls_sec_param_get_name(sec_param)),

672

safer_gnutls_strerror(ret));

673

goto globalfail;

674

}

675

} else if(debug){

676

fprintf_plus(stderr, "DH bits explicitly set to %u\n",

677

mc->dh_bits);

678

}

679

561

ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);

680

562

if(ret != GNUTLS_E_SUCCESS){

681

fprintf_plus(stderr, "Error in GnuTLS prime generation (%u bits):"

682

" %s\n", mc->dh_bits, safer_gnutls_strerror(ret));

563

fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",

564

safer_gnutls_strerror(ret));

683

565

goto globalfail;

684

566

}

685

567

1183

1065

timed out */

1184

1066

1185

1067

if(quit_now){

1186

avahi_s_service_resolver_free(r);

1187

1068

return;

1188

1069

}

1189

1070

1576

1457

error_t ret_errno = 0;

1577

1458

if(seteuid(0) == -1){

1578

1459

ret_errno = errno;

1460

perror_plus("seteuid");

1579

1461

}

1580

1462

errno = old_errno;

1581

1463

return ret_errno;

1592

1474

}

1593

1475

if(setuid(0) == -1){

1594

1476

ret_errno = errno;

1477

perror_plus("seteuid");

1595

1478

}

1596

1479

errno = old_errno;

1597

1480

return ret_errno;

1604

1487

error_t ret_errno = 0;

1605

1488

if(seteuid(uid) == -1){

1606

1489

ret_errno = errno;

1490

perror_plus("seteuid");

1607

1491

}

1608

1492

errno = old_errno;

1609

1493

return ret_errno;

1616

1500

error_t ret_errno = 0;

1617

1501

if(setuid(uid) == -1){

1618

1502

ret_errno = errno;

1503

perror_plus("setuid");

1619

1504

}

1620

1505

errno = old_errno;

1621

1506

return ret_errno;

1622

1507

}

1623

1508

1509

#ifndef O_CLOEXEC

1510

/*

1511

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

1512

* Descriptor Flags".

1513

| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |

1514

*/

1515

__attribute__((warn_unused_result))

1516

static int set_cloexec_flag(int fd){

1517

int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));

1518

/* If reading the flags failed, return error indication now. */

1519

if(ret < 0){

1520

return ret;

1521

}

1522

/* Store modified flag word in the descriptor. */

1523

return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,

1524

ret | FD_CLOEXEC));

1525

}

1526

#endif /* not O_CLOEXEC */

1527

1624

1528

__attribute__((nonnull))

1625

1529

void run_network_hooks(const char *mode, const char *interface,

1626

1530

const float delay){

1627

struct dirent **direntries = NULL;

1531

struct dirent **direntries;

1628

1532

if(hookdir_fd == -1){

1629

hookdir_fd = open(hookdir, O_RDONLY);

1533

hookdir_fd = open(hookdir, O_RDONLY |

1534

#ifdef O_CLOEXEC

1535

O_CLOEXEC

1536

#else /* not O_CLOEXEC */

1537

0

1538

#endif /* not O_CLOEXEC */

1539

);

1630

1540

if(hookdir_fd == -1){

1631

1541

if(errno == ENOENT){

1632

1542

if(debug){

1638

1548

}

1639

1549

return;

1640

1550

}

1551

#ifndef O_CLOEXEC

1552

if(set_cloexec_flag(hookdir_fd) < 0){

1553

perror_plus("set_cloexec_flag");

1554

if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){

1555

perror_plus("close");

1556

} else {

1557

hookdir_fd = -1;

1558

}

1559

return;

1560

}

1561

#endif /* not O_CLOEXEC */

1641

1562

}

1642

1563

#ifdef __GLIBC__

1643

1564

#if __GLIBC_PREREQ(2, 15)

1668

1589

if(hook_pid == 0){

1669

1590

/* Child */

1670

1591

/* Raise privileges */

1671

errno = raise_privileges_permanently();

1672

if(errno != 0){

1592

if(raise_privileges_permanently() != 0){

1673

1593

perror_plus("Failed to raise privileges");

1674

1594

_exit(EX_NOPERM);

1675

1595

}

1742

1662

_exit(EX_OSERR);

1743

1663

}

1744

1664

}

1745

int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);

1746

if(hook_fd == -1){

1747

perror_plus("openat");

1748

_exit(EXIT_FAILURE);

1749

}

1750

if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){

1751

perror_plus("close");

1752

_exit(EXIT_FAILURE);

1753

}

1754

if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },

1755

environ) == -1){

1665

if(fexecve(hookdir_fd, (char *const [])

1666

{ direntry->d_name, NULL }, environ) == -1){

1756

1667

perror_plus("fexecve");

1757

1668

_exit(EXIT_FAILURE);

1758

1669

}

1759

1670

} else {

1760

if(hook_pid == -1){

1761

perror_plus("fork");

1762

free(direntry);

1763

continue;

1764

}

1765

1671

int status;

1766

1672

if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){

1767

1673

perror_plus("waitpid");

1768

free(direntry);

1769

1674

continue;

1770

1675

}

1771

1676

if(WIFEXITED(status)){

1773

1678

fprintf_plus(stderr, "Warning: network hook \"%s\" exited"

1774

1679

" with status %d\n", direntry->d_name,

1775

1680

WEXITSTATUS(status));

1776

free(direntry);

1777

1681

continue;

1778

1682

}

1779

1683

} else if(WIFSIGNALED(status)){

1780

1684

fprintf_plus(stderr, "Warning: network hook \"%s\" died by"

1781

1685

" signal %d\n", direntry->d_name,

1782

1686

WTERMSIG(status));

1783

free(direntry);

1784

1687

continue;

1785

1688

} else {

1786

1689

fprintf_plus(stderr, "Warning: network hook \"%s\""

1787

1690

" crashed\n", direntry->d_name);

1788

free(direntry);

1789

1691

continue;

1790

1692

}

1791

1693

}

1793

1695

fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",

1794

1696

direntry->d_name);

1795

1697

}

1796

free(direntry);

1797

1698

}

1798

free(direntries);

1799

1699

if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){

1800

1700

perror_plus("close");

1801

1701

} else {

1858

1758

/* Raise privileges */

1859

1759

ret_errno = raise_privileges();

1860

1760

if(ret_errno != 0){

1861

errno = ret_errno;

1862

1761

perror_plus("Failed to raise privileges");

1863

1762

}

1864

1763

1968

1867

/* Raise privileges */

1969

1868

ret_errno = raise_privileges();

1970

1869

if(ret_errno != 0){

1971

errno = ret_errno;

1972

1870

perror_plus("Failed to raise privileges");

1973

1871

}

1974

1872

2007

1905

}

2008

1906

2009

1907

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

2010

mandos_context mc = { .server = NULL, .dh_bits = 0,

1908

mandos_context mc = { .server = NULL, .dh_bits = 1024,

2011

1909

.priority = "SECURE256:!CTYPE-X.509:"

2012

"+CTYPE-OPENPGP:!RSA", .current_server = NULL,

1910

"+CTYPE-OPENPGP", .current_server = NULL,

2013

1911

.interfaces = NULL, .interfaces_size = 0 };

2014

1912

AvahiSServiceBrowser *sb = NULL;

2015

1913

error_t ret_errno;

2381

2279

2382

2280

/* If no interfaces were specified, make a list */

2383

2281

if(mc.interfaces == NULL){

2384

struct dirent **direntries = NULL;

2282

struct dirent **direntries;

2385

2283

/* Look for any good interfaces */

2386

2284

ret = scandir(sys_class_net, &direntries, good_interface,

2387

2285

alphasort);

2393

2291

if(ret_errno != 0){

2394

2292

errno = ret_errno;

2395

2293

perror_plus("argz_add");

2396

free(direntries[i]);

2397

2294

continue;

2398

2295

}

2399

2296

if(debug){

2400

2297

fprintf_plus(stderr, "Will use interface \"%s\"\n",

2401

2298

direntries[i]->d_name);

2402

2299

}

2403

free(direntries[i]);

2404

2300

}

2405

2301

free(direntries);

2406

2302

} else {

2407

if(ret == 0){

2408

free(direntries);

2409

}

2303

free(direntries);

2410

2304

fprintf_plus(stderr, "Could not find a network interface\n");

2411

2305

exitcode = EXIT_FAILURE;

2412

2306

goto end;

2676

2570

mc.current_server->prev->next = NULL;

2677

2571

while(mc.current_server != NULL){

2678

2572

server *next = mc.current_server->next;

2679

#ifdef __GNUC__

2680

#pragma GCC diagnostic push

2681

#pragma GCC diagnostic ignored "-Wcast-qual"

2682

#endif

2683

free((char *)(mc.current_server->ip));

2684

#ifdef __GNUC__

2685

#pragma GCC diagnostic pop

2686

#endif

2687

2573

free(mc.current_server);

2688

2574

mc.current_server = next;

2689

2575

}

2693

2579

{

2694

2580

ret_errno = raise_privileges();

2695

2581

if(ret_errno != 0){

2696

errno = ret_errno;

2697

2582

perror_plus("Failed to raise privileges");

2698

2583

} else {

2699

2584

2722

2607

2723

2608

ret_errno = lower_privileges_permanently();

2724

2609

if(ret_errno != 0){

2725

errno = ret_errno;

2726

2610

perror_plus("Failed to lower privileges permanently");

2727

2611

}

2728

2612

}

2733

2617

/* Removes the GPGME temp directory and all files inside */

2734

2618

if(tempdir != NULL){

2735

2619

struct dirent **direntries = NULL;

2736

int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY |

2737

O_NOFOLLOW));

2738

if(tempdir_fd == -1){

2739

perror_plus("open");

2740

} else {

2741

#ifdef __GLIBC__

2742

#if __GLIBC_PREREQ(2, 15)

2743

int numentries = scandirat(tempdir_fd, ".", &direntries,

2744

notdotentries, alphasort);

2745

#else /* not __GLIBC_PREREQ(2, 15) */

2746

int numentries = scandir(tempdir, &direntries, notdotentries,

2747

alphasort);

2748

#endif /* not __GLIBC_PREREQ(2, 15) */

2749

#else /* not __GLIBC__ */

2750

int numentries = scandir(tempdir, &direntries, notdotentries,

2751

alphasort);

2752

#endif /* not __GLIBC__ */

2753

if(numentries >= 0){

2754

for(int i = 0; i < numentries; i++){

2755

ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);

2756

if(ret == -1){

2757

fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"

2758

" \"%s\", 0): %s\n", tempdir,

2759

direntries[i]->d_name, strerror(errno));

2760

}

2761

free(direntries[i]);

2762

}

2763

2764

/* need to clean even if 0 because man page doesn't specify */

2765

free(direntries);

2766

if(numentries == -1){

2767

perror_plus("scandir");

2768

}

2769

ret = rmdir(tempdir);

2770

if(ret == -1 and errno != ENOENT){

2771

perror_plus("rmdir");

2772

}

2620

struct dirent *direntry = NULL;

2621

int numentries = scandir(tempdir, &direntries, notdotentries,

2622

alphasort);

2623

if(numentries > 0){

2624

for(int i = 0; i < numentries; i++){

2625

direntry = direntries[i];

2626

char *fullname = NULL;

2627

ret = asprintf(&fullname, "%s/%s", tempdir,

2628

direntry->d_name);

2629

if(ret < 0){

2630

perror_plus("asprintf");

2631

continue;

2632

}

2633

ret = remove(fullname);

2634

if(ret == -1){

2635

fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,

2636

strerror(errno));

2637

}

2638

free(fullname);

2773

2639

}

2774

TEMP_FAILURE_RETRY(close(tempdir_fd));

2640

}

2641

2642

/* need to clean even if 0 because man page doesn't specify */

2643

free(direntries);

2644

if(numentries == -1){

2645

perror_plus("scandir");

2646

}

2647

ret = rmdir(tempdir);

2648

if(ret == -1 and errno != ENOENT){

2649

perror_plus("rmdir");

2775

2650

}

2776

2651

}

2777

2652