/mandos/trunk : revision 24.1.39

32

#define _LARGEFILE_SOURCE

33

#define _FILE_OFFSET_BITS 64

34

35

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

35

#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */

36

37

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

38

stdout, ferror() */

37

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

38

ferror() */

39

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

40

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

41

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

42

srand() */

43

#include <stdbool.h> /* bool, true */

44

#include <string.h> /* memset(), strcmp(), strlen(),

45

strerror(), asprintf(), strcpy() */

45

strerror(), memcpy(), strcpy() */

46

#include <sys/ioctl.h> /* ioctl */

47

#include <net/if.h> /* ifreq, SIOCGIFFLAGS, SIOCSIFFLAGS,

48

IFF_UP */

47

49

#include <sys/types.h> /* socket(), inet_pton(), sockaddr,

48

50

sockaddr_in6, PF_INET6,

49

51

SOCK_STREAM, INET6_ADDRSTRLEN,

50

52

uid_t, gid_t */

51

#include <inttypes.h> /* PRIu16 */

52

53

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

53

54

struct in6_addr, inet_pton(),

54

55

connect() */

81

82

#include <avahi-common/error.h>

82

83

84

/* GnuTLS */

84

#include <gnutls/gnutls.h> /* All GnuTLS types, constants and

85

functions:

85

#include <gnutls/gnutls.h> /* All GnuTLS types, constants and functions

86

gnutls_*

87

init_gnutls_session(),

88

GNUTLS_* */

90

GNUTLS_OPENPGP_FMT_BASE64 */

91

92

/* GPGME */

93

#include <gpgme.h> /* All GPGME types, constants and

94

functions:

93

#include <gpgme.h> /* All GPGME types, constants and functions

95

94

gpgme_*

96

95

GPGME_PROTOCOL_OpenPGP,

97

96

GPG_ERR_NO_* */

214

213

fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",

215

214

gpgme_strsource(rc), gpgme_strerror(rc));

216

215

plaintext_length = -1;

217

if (debug){

218

gpgme_decrypt_result_t result;

219

result = gpgme_op_decrypt_result(ctx);

220

if (result == NULL){

221

fprintf(stderr, "gpgme_op_decrypt_result failed\n");

222

} else {

223

fprintf(stderr, "Unsupported algorithm: %s\n",

224

result->unsupported_algorithm);

225

fprintf(stderr, "Wrong key usage: %u\n",

226

result->wrong_key_usage);

227

if(result->file_name != NULL){

228

fprintf(stderr, "File name: %s\n", result->file_name);

229

}

230

gpgme_recipient_t recipient;

231

recipient = result->recipients;

232

if(recipient){

233

while(recipient != NULL){

234

fprintf(stderr, "Public key algorithm: %s\n",

235

gpgme_pubkey_algo_name(recipient->pubkey_algo));

236

fprintf(stderr, "Key ID: %s\n", recipient->keyid);

237

fprintf(stderr, "Secret key available: %s\n",

238

recipient->status == GPG_ERR_NO_SECKEY

239

? "No" : "Yes");

240

recipient = recipient->next;

241

}

242

}

243

}

244

}

245

216

goto decrypt_end;

246

217

}

247

218

249

220

fprintf(stderr, "Decryption of OpenPGP data succeeded\n");

250

221

}

251

222

223

if (debug){

224

gpgme_decrypt_result_t result;

225

result = gpgme_op_decrypt_result(ctx);

226

if (result == NULL){

227

fprintf(stderr, "gpgme_op_decrypt_result failed\n");

228

} else {

229

fprintf(stderr, "Unsupported algorithm: %s\n",

230

result->unsupported_algorithm);

231

fprintf(stderr, "Wrong key usage: %d\n",

232

result->wrong_key_usage);

233

if(result->file_name != NULL){

234

fprintf(stderr, "File name: %s\n", result->file_name);

235

}

236

gpgme_recipient_t recipient;

237

recipient = result->recipients;

238

if(recipient){

239

while(recipient != NULL){

240

fprintf(stderr, "Public key algorithm: %s\n",

241

gpgme_pubkey_algo_name(recipient->pubkey_algo));

242

fprintf(stderr, "Key ID: %s\n", recipient->keyid);

243

fprintf(stderr, "Secret key available: %s\n",

244

recipient->status == GPG_ERR_NO_SECKEY

245

? "No" : "Yes");

246

recipient = recipient->next;

247

}

248

}

249

}

250

}

251

252

/* Seek back to the beginning of the GPGME plaintext data buffer */

253

if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){

254

perror("pgpme_data_seek");

281

}

282

plaintext_length += ret;

283

}

284

285

if(debug){

286

fprintf(stderr, "Decrypted password is: ");

287

for(ssize_t i = 0; i < plaintext_length; i++){

301

}

302

303

static const char * safer_gnutls_strerror (int value) {

304

const char *ret = gnutls_strerror (value); /* Spurious warning */

304

const char *ret = gnutls_strerror (value);

305

if (ret == NULL)

306

ret = "(unknown)";

307

return ret;

314

}

315

316

static int init_gnutls_global(mandos_context *mc,

317

const char *pubkeyfilename,

318

const char *seckeyfilename){

317

const char *pubkeyfile,

318

const char *seckeyfile){

319

int ret;

320

321

if(debug){

340

/* OpenPGP credentials */

341

gnutls_certificate_allocate_credentials(&mc->cred);

342

if (ret != GNUTLS_E_SUCCESS){

343

fprintf (stderr, "GnuTLS memory error: %s\n", /* Spurious

344

warning */

343

fprintf (stderr, "GnuTLS memory error: %s\n",

345

344

safer_gnutls_strerror(ret));

346

345

gnutls_global_deinit ();

347

346

return -1;

349

348

350

349

if(debug){

351

350

fprintf(stderr, "Attempting to use OpenPGP certificate %s"

352

" and keyfile %s as GnuTLS credentials\n", pubkeyfilename,

353

seckeyfilename);

351

" and keyfile %s as GnuTLS credentials\n", pubkeyfile,

352

seckeyfile);

354

353

}

355

354

356

355

ret = gnutls_certificate_set_openpgp_key_file

357

(mc->cred, pubkeyfilename, seckeyfilename,

358

GNUTLS_OPENPGP_FMT_BASE64);

356

(mc->cred, pubkeyfile, seckeyfile, GNUTLS_OPENPGP_FMT_BASE64);

359

357

if (ret != GNUTLS_E_SUCCESS) {

360

358

fprintf(stderr,

361

359

"Error[%d] while reading the OpenPGP key pair ('%s',"

362

" '%s')\n", ret, pubkeyfilename, seckeyfilename);

360

" '%s')\n", ret, pubkeyfile, seckeyfile);

363

361

fprintf(stdout, "The GnuTLS error is: %s\n",

364

362

safer_gnutls_strerror(ret));

365

363

goto globalfail;

380

378

}

381

379

382

380

gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);

383

381

384

382

return 0;

385

383

386

384

globalfail:

387

385

388

386

gnutls_certificate_free_credentials(mc->cred);

389

387

gnutls_global_deinit();

390

388

return -1;

389

391

390

}

392

391

393

392

static int init_gnutls_session(mandos_context *mc,

456

455

}

457

456

458

457

if(debug){

459

fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16

460

"\n", ip, port);

458

fprintf(stderr, "Setting up a tcp connection to %s, port %d\n",

459

ip, port);

461

460

}

462

461

463

462

tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);

465

464

perror("socket");

466

465

return -1;

467

466

}

468

467

469

468

if(debug){

470

469

if(if_indextoname((unsigned int)if_index, interface) == NULL){

471

470

perror("if_indextoname");

474

473

fprintf(stderr, "Binding to interface %s\n", interface);

475

474

}

476

475

477

memset(&to, 0, sizeof(to));

476

memset(&to,0,sizeof(to)); /* Spurious warning */

478

477

to.in6.sin6_family = AF_INET6;

479

478

/* It would be nice to have a way to detect if we were passed an

480

479

IPv4 address here. Now we assume an IPv6 address. */

487

486

fprintf(stderr, "Bad address: %s\n", ip);

488

487

return -1;

489

488

}

490

to.in6.sin6_port = htons(port); /* Spurious warning */

489

to.in6.sin6_port = htons(port); /* Spurious warning */

491

490

492

491

to.in6.sin6_scope_id = (uint32_t)if_index;

493

492

494

493

if(debug){

495

fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,

496

port);

494

fprintf(stderr, "Connection to: %s, port %d\n", ip, port);

497

495

char addrstr[INET6_ADDRSTRLEN] = "";

498

496

if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,

499

497

sizeof(addrstr)) == NULL){

510

508

perror("connect");

511

509

return -1;

512

510

}

513

511

514

512

const char *out = mandos_protocol_version;

515

513

written = 0;

516

514

while (true){

534

532

}

535

533

}

536

534

}

537

535

538

536

if(debug){

539

537

fprintf(stderr, "Establishing TLS session with %s\n", ip);

540

538

}

541

539

542

540

gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);

543

541

544

542

do{

545

543

ret = gnutls_handshake (session);

546

544

} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);

560

558

fprintf(stderr, "Retrieving pgp encrypted password from %s\n",

561

559

ip);

562

560

}

563

561

564

562

while(true){

565

563

buffer_capacity = adjustbuffer(&buffer, buffer_length,

566

564

buffer_capacity);

634

632

} else {

635

633

retval = -1;

636

634

}

637

} else {

638

retval = -1;

639

635

}

640

636

641

637

/* Shutdown procedure */

662

658

flags,

663

659

void* userdata) {

664

660

mandos_context *mc = userdata;

665

assert(r);

661

assert(r); /* Spurious warning */

666

662

667

663

/* Called whenever a service has been resolved successfully or

668

664

timed out */

680

676

char ip[AVAHI_ADDRESS_STR_MAX];

681

677

avahi_address_snprint(ip, sizeof(ip), address);

682

678

if(debug){

683

fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"

684

PRIu16 ") on port %d\n", name, host_name, ip,

685

interface, port);

679

fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %d) on"

680

" port %d\n", name, host_name, ip, interface, port);

686

681

}

687

682

int ret = start_mandos_communication(ip, port, interface, mc);

688

683

if (ret == 0){

689

avahi_simple_poll_quit(mc->simple_poll);

684

exit(EXIT_SUCCESS);

690

685

}

691

686

}

692

687

}

704

699

flags,

705

700

void* userdata) {

706

701

mandos_context *mc = userdata;

707

assert(b);

702

assert(b); /* Spurious warning */

708

703

709

704

/* Called whenever a new services becomes available on the LAN or

710

705

is removed from the LAN */

746

741

747

742

/* Combines file name and path and returns the malloced new

748

743

string. some sane checks could/should be added */

749

static char *combinepath(const char *first, const char *second){

750

char *tmp;

751

int ret = asprintf(&tmp, "%s/%s", first, second);

752

if(ret < 0){

744

static const char *combinepath(const char *first, const char *second){

745

size_t f_len = strlen(first);

746

size_t s_len = strlen(second);

747

char *tmp = malloc(f_len + s_len + 2);

748

if (tmp == NULL){

753

749

return NULL;

754

750

}

751

if(f_len > 0){

752

memcpy(tmp, first, f_len); /* Spurious warning */

753

}

754

tmp[f_len] = '/';

755

if(s_len > 0){

756

memcpy(tmp + f_len + 1, second, s_len); /* Spurious warning */

757

}

758

tmp[f_len + 1 + s_len] = '\0';

755

759

return tmp;

756

760

}

757

761

768

772

gid_t gid;

769

773

char *connect_to = NULL;

770

774

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

771

char *pubkeyfilename = NULL;

772

char *seckeyfilename = NULL;

773

const char *pubkeyname = "pubkey.txt";

774

const char *seckeyname = "seckey.txt";

775

const char *pubkeyfile = "pubkey.txt";

776

const char *seckeyfile = "seckey.txt";

775

777

mandos_context mc = { .simple_poll = NULL, .server = NULL,

776

.dh_bits = 1024, .priority = "SECURE256"

777

":!CTYPE-X.509:+CTYPE-OPENPGP" };

778

.dh_bits = 1024, .priority = "SECURE256"};

778

779

bool gnutls_initalized = false;

779

780

781

{

782

783

{ .name = "debug", .key = 128,

783

784

.doc = "Debug mode", .group = 3 },

784

785

{ .name = "connect", .key = 'c',

785

.arg = "ADDRESS:PORT",

786

.doc = "Connect directly to a specific Mandos server",

786

.arg = "IP",

787

.doc = "Connect directly to a sepcified mandos server",

787

788

.group = 1 },

788

789

{ .name = "interface", .key = 'i',

789

.arg = "NAME",

790

.doc = "Interface that will be used to search for Mandos"

791

" servers",

790

.arg = "INTERFACE",

791

.doc = "Interface that Avahi will conntect through",

792

.group = 1 },

793

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

794

.arg = "DIRECTORY",

795

.doc = "Directory to read the OpenPGP key files from",

794

.arg = "KEYDIR",

795

.doc = "Directory where the openpgp keyring is",

796

.group = 1 },

797

{ .name = "seckey", .key = 's',

798

.arg = "FILE",

799

.doc = "OpenPGP secret key file base name",

798

.arg = "SECKEY",

799

.doc = "Secret openpgp key for gnutls authentication",

800

.group = 1 },

801

{ .name = "pubkey", .key = 'p',

802

.arg = "FILE",

803

.doc = "OpenPGP public key file base name",

802

.arg = "PUBKEY",

803

.doc = "Public openpgp key for gnutls authentication",

804

.group = 2 },

805

{ .name = "dh-bits", .key = 129,

806

.arg = "BITS",

807

.doc = "Bit length of the prime number used in the"

808

" Diffie-Hellman key exchange",

807

.doc = "dh-bits to use in gnutls communication",

809

808

.group = 2 },

810

809

{ .name = "priority", .key = 130,

811

.arg = "STRING",

812

.doc = "GnuTLS priority string for the TLS handshake",

813

.group = 1 },

810

.arg = "PRIORITY",

811

.doc = "GNUTLS priority", .group = 1 },

814

812

{ .name = NULL }

815

813

};

814

816

815

817

816

error_t parse_opt (int key, char *arg,

818

817

struct argp_state *state) {

819

818

/* Get the INPUT argument from `argp_parse', which we know is

820

819

a pointer to our plugin list pointer. */

821

820

switch (key) {

822

case 128: /* --debug */

821

case 128:

823

822

debug = true;

824

823

break;

825

case 'c': /* --connect */

824

case 'c':

826

825

connect_to = arg;

827

826

break;

828

case 'i': /* --interface */

827

case 'i':

829

828

interface = arg;

830

829

break;

831

case 'd': /* --keydir */

830

case 'd':

832

831

keydir = arg;

833

832

break;

834

case 's': /* --seckey */

835

seckeyname = arg;

836

break;

837

case 'p': /* --pubkey */

838

pubkeyname = arg;

839

break;

840

case 129: /* --dh-bits */

833

case 's':

834

seckeyfile = arg;

835

break;

836

case 'p':

837

pubkeyfile = arg;

838

break;

839

case 129:

841

840

errno = 0;

842

841

mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);

843

842

if (errno){

845

844

exit(EXIT_FAILURE);

846

845

}

847

846

break;

848

case 130: /* --priority */

847

case 130:

849

848

mc.priority = arg;

850

849

break;

851

850

case ARGP_KEY_ARG:

852

851

argp_usage (state);

853

case ARGP_KEY_END:

854

852

break;

853

case ARGP_KEY_END:

854

break;

855

default:

856

return ARGP_ERR_UNKNOWN;

857

}

858

return 0;

859

}

860

861

struct argp argp = { .options = options, .parser = parse_opt,

862

.args_doc = "",

863

.doc = "Mandos client -- Get and decrypt"

864

" passwords from a Mandos server" };

864

" passwords from mandos server" };

865

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

866

if (ret == ARGP_ERR_UNKNOWN){

867

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

867

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

868

exitcode = EXIT_FAILURE;

869

goto end;

870

}

871

}

872

873

pubkeyfilename = combinepath(keydir, pubkeyname);

874

if (pubkeyfilename == NULL){

875

perror("combinepath");

876

exitcode = EXIT_FAILURE;

877

goto end;

878

}

879

880

seckeyfilename = combinepath(keydir, seckeyname);

881

if (seckeyfilename == NULL){

882

perror("combinepath");

883

exitcode = EXIT_FAILURE;

884

goto end;

885

}

886

887

ret = init_gnutls_global(&mc, pubkeyfilename, seckeyfilename);

872

873

pubkeyfile = combinepath(keydir, pubkeyfile);

874

if (pubkeyfile == NULL){

875

perror("combinepath");

876

exitcode = EXIT_FAILURE;

877

goto end;

878

}

879

880

seckeyfile = combinepath(keydir, seckeyfile);

881

if (seckeyfile == NULL){

882

perror("combinepath");

883

goto end;

884

}

885

886

ret = init_gnutls_global(&mc, pubkeyfile, seckeyfile);

888

887

if (ret == -1){

889

fprintf(stderr, "init_gnutls_global failed\n");

890

exitcode = EXIT_FAILURE;

888

fprintf(stderr, "init_gnutls_global\n");

891

889

goto end;

892

890

} else {

893

891

gnutls_initalized = true;

894

892

}

895

896

/* If the interface is down, bring it up */

897

{

898

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

899

if(sd < 0) {

900

perror("socket");

901

exitcode = EXIT_FAILURE;

902

goto end;

903

}

904

strcpy(network.ifr_name, interface);

905

ret = ioctl(sd, SIOCGIFFLAGS, &network);

906

if(ret == -1){

907

perror("ioctl SIOCGIFFLAGS");

908

exitcode = EXIT_FAILURE;

909

goto end;

910

}

911

if((network.ifr_flags & IFF_UP) == 0){

912

network.ifr_flags |= IFF_UP;

913

ret = ioctl(sd, SIOCSIFFLAGS, &network);

914

if(ret == -1){

915

perror("ioctl SIOCSIFFLAGS");

916

exitcode = EXIT_FAILURE;

917

goto end;

918

}

919

}

920

close(sd);

921

}

922

893

923

894

uid = getuid();

924

895

gid = getgid();

925

896

926

897

ret = setuid(uid);

927

898

if (ret == -1){

928

899

perror("setuid");

966

937

goto end;

967

938

}

968

939

940

/* If the interface is down, bring it up */

941

{

942

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

943

if(sd < 0) {

944

perror("socket");

945

exitcode = EXIT_FAILURE;

946

goto end;

947

}

948

strcpy(network.ifr_name, interface); /* Spurious warning */

949

ret = ioctl(sd, SIOCGIFFLAGS, &network);

950

if(ret == -1){

951

perror("ioctl SIOCGIFFLAGS");

952

exitcode = EXIT_FAILURE;

953

goto end;

954

}

955

if((network.ifr_flags & IFF_UP) == 0){

956

network.ifr_flags |= IFF_UP;

957

ret = ioctl(sd, SIOCSIFFLAGS, &network);

958

if(ret == -1){

959

perror("ioctl SIOCSIFFLAGS");

960

exitcode = EXIT_FAILURE;

961

goto end;

962

}

963

}

964

close(sd);

965

}

966

969

967

if (not debug){

970

968

avahi_set_log_function(empty_log);

971

969

}

981

979

exitcode = EXIT_FAILURE;

982

980

goto end;

983

981

}

984

982

985

983

{

986

984

AvahiServerConfig config;

987

985

/* Do not publish any local Zeroconf records */

990

988

config.publish_addresses = 0;

991

989

config.publish_workstation = 0;

992

990

config.publish_domain = 0;

993

991

994

992

/* Allocate a new server */

995

993

mc.server = avahi_server_new(avahi_simple_poll_get

996

994

(mc.simple_poll), &config, NULL,

997

995

NULL, &error);

998

996

999

997

/* Free the Avahi configuration data */

1000

998

avahi_server_config_free(&config);

1001

999

}

1021

1019

}

1022

1020

1023

1021

/* Run the main loop */

1024

1022

1025

1023

if (debug){

1026

1024

fprintf(stderr, "Starting Avahi loop search\n");

1027

1025

}

1029

1027

avahi_simple_poll_loop(mc.simple_poll);

1030

1028

1031

1029

end:

1032

1030

1033

1031

if (debug){

1034

1032

fprintf(stderr, "%s exiting\n", argv[0]);

1035

1033

}

1040

1038

1041

1039

if (mc.server != NULL)

1042

1040

avahi_server_free(mc.server);

1043

1041

1044

1042

if (mc.simple_poll != NULL)

1045

1043

avahi_simple_poll_free(mc.simple_poll);

1046

free(pubkeyfilename);

1047

free(seckeyfilename);

1048

1044

free(pubkeyfile);

1045

free(seckeyfile);

1046

1049

1047

if (gnutls_initalized){

1050

1048

gnutls_certificate_free_credentials(mc.cred);

1051

1049

gnutls_global_deinit ();