/mandos/trunk : revision 149

47

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

48

sockaddr_in6, PF_INET6,

49

SOCK_STREAM, INET6_ADDRSTRLEN,

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uid_t, gid_t */

51

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

50

uid_t, gid_t, open(), opendir(), DIR */

51

#include <sys/stat.h> /* open() */

52

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

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struct in6_addr, inet_pton(),

54

connect() */

55

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

56

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

57

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

55

58

#include <assert.h> /* assert() */

56

59

#include <errno.h> /* perror(), errno */

57

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#include <time.h> /* time() */

58

61

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

59

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SIOCSIFFLAGS, if_indextoname(),

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if_nametoindex(), IF_NAMESIZE */

64

#include <netinet/in.h>

61

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

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66

getuid(), getgid(), setuid(),

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setgid() */

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#include <netinet/in.h>

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68

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

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69

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

67

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

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101

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#define BUFFER_SIZE 256

100

103

104

/*

105

#define PATHDIR "/conf/conf.d/mandos"

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*/

107

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#define PATHDIR "/conf/conf.d/mandos"

109

#define SECKEY "seckey.txt"

110

#define PUBKEY "pupkey.txt"

111

101

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bool debug = false;

102

static const char *keydir = "/conf/conf.d/mandos";

103

113

static const char mandos_protocol_version[] = "1";

104

114

const char *argp_program_version = "password-request 1.0";

105

115

const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";

112

122

unsigned int dh_bits;

113

123

gnutls_dh_params_t dh_params;

114

124

const char *priority;

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gpgme_ctx_t ctx;

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126

} mandos_context;

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127

117

128

/*

132

143

}

133

144

134

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/*

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* Decrypt OpenPGP data using keyrings in HOMEDIR.

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* Returns -1 on error

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* Initialize GPGME.

137

147

*/

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static ssize_t pgp_packet_decrypt (const char *cryptotext,

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size_t crypto_size,

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char **plaintext,

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const char *homedir){

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gpgme_data_t dh_crypto, dh_plain;

143

gpgme_ctx_t ctx;

148

static bool init_gpgme(mandos_context *mc, const char *seckey,

149

const char *pubkey, const char *tempdir){

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int ret;

144

151

gpgme_error_t rc;

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ssize_t ret;

146

size_t plaintext_capacity = 0;

147

ssize_t plaintext_length = 0;

148

152

gpgme_engine_info_t engine_info;

153

154

155

/*

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* Helper function to insert pub and seckey to the enigne keyring.

157

*/

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bool import_key(const char *filename){

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int fd;

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gpgme_data_t pgp_data;

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fd = TEMP_FAILURE_RETRY(open(filename, O_RDONLY));

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if(fd == -1){

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perror("open");

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return false;

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}

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

169

if (rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

174

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rc = gpgme_op_import(mc->ctx, pgp_data);

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if (rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

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ret = TEMP_FAILURE_RETRY(close(fd));

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if(ret == -1){

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perror("close");

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}

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gpgme_data_release(pgp_data);

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return true;

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}

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if (debug){

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fprintf(stderr, "Trying to decrypt OpenPGP data\n");

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fprintf(stderr, "Initialize gpgme\n");

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}

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/* Init GPGME */

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gpgme_check_version(NULL);

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rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

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if (rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return -1;

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return false;

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}

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/* Set GPGME home directory for the OpenPGP engine only */

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/* Set GPGME home directory for the OpenPGP engine only */

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rc = gpgme_get_engine_info (&engine_info);

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if (rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return -1;

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return false;

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}

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while(engine_info != NULL){

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if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){

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gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,

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engine_info->file_name, homedir);

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engine_info->file_name, tempdir);

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break;

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}

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engine_info = engine_info->next;

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}

178

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if(engine_info == NULL){

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fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);

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return -1;

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fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);

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return false;

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}

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/* Create new GPGME "context" */

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rc = gpgme_new(&(mc->ctx));

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if (rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

230

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if (not import_key(pubkey) or not import_key(seckey)){

232

return false;

233

}

234

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return true;

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}

237

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/*

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* Decrypt OpenPGP data.

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* Returns -1 on error

241

*/

242

static ssize_t pgp_packet_decrypt (const mandos_context *mc,

243

const char *cryptotext,

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size_t crypto_size,

245

char **plaintext){

246

gpgme_data_t dh_crypto, dh_plain;

247

gpgme_error_t rc;

248

ssize_t ret;

249

size_t plaintext_capacity = 0;

250

ssize_t plaintext_length = 0;

251

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if (debug){

253

fprintf(stderr, "Trying to decrypt OpenPGP data\n");

181

254

}

182

255

183

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/* Create new GPGME data buffer from memory cryptotext */

198

271

return -1;

199

272

}

200

273

201

/* Create new GPGME "context" */

202

rc = gpgme_new(&ctx);

203

if (rc != GPG_ERR_NO_ERROR){

204

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

205

gpgme_strsource(rc), gpgme_strerror(rc));

206

plaintext_length = -1;

207

goto decrypt_end;

208

}

209

210

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/* Decrypt data from the cryptotext data buffer to the plaintext

211

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data buffer */

212

rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);

276

rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);

213

277

if (rc != GPG_ERR_NO_ERROR){

214

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

215

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gpgme_strsource(rc), gpgme_strerror(rc));

216

280

plaintext_length = -1;

217

281

if (debug){

218

282

gpgme_decrypt_result_t result;

219

result = gpgme_op_decrypt_result(ctx);

283

result = gpgme_op_decrypt_result(mc->ctx);

220

284

if (result == NULL){

221

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

222

286

} else {

610

674

gnutls_bye (session, GNUTLS_SHUT_RDWR);

611

675

612

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if (buffer_length > 0){

613

decrypted_buffer_size = pgp_packet_decrypt(buffer,

677

decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,

614

678

buffer_length,

615

&decrypted_buffer,

616

keydir);

679

&decrypted_buffer);

617

680

if (decrypted_buffer_size >= 0){

618

681

written = 0;

619

682

while(written < (size_t) decrypted_buffer_size){

642

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643

706

mandos_end:

644

707

free(buffer);

645

close(tcp_sd);

708

ret = TEMP_FAILURE_RETRY(close(tcp_sd));

709

if(ret == -1){

710

perror("close");

711

}

646

712

gnutls_deinit (session);

647

713

return retval;

648

714

}

744

810

}

745

811

}

746

812

747

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

748

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){

753

return NULL;

754

}

755

return tmp;

756

}

757

758

759

813

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

760

814

AvahiSServiceBrowser *sb = NULL;

761

815

int error;

767

821

uid_t uid;

768

822

gid_t gid;

769

823

char *connect_to = NULL;

824

char tempdir[] = "/tmp/mandosXXXXXX";

770

825

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";

826

const char *seckey = PATHDIR "/" SECKEY;

827

const char *pubkey = PATHDIR "/" PUBKEY;

828

775

829

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

776

830

.dh_bits = 1024, .priority = "SECURE256"

777

831

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

778

832

bool gnutls_initalized = false;

833

bool pgpme_initalized = false;

779

834

780

835

{

781

836

struct argp_option options[] = {

790

845

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

791

846

" servers",

792

847

.group = 1 },

793

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

794

.arg = "DIRECTORY",

795

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

796

.group = 1 },

797

848

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

798

849

.arg = "FILE",

799

850

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

828

879

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

829

880

interface = arg;

830

881

break;

831

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

832

keydir = arg;

833

break;

834

882

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

835

seckeyname = arg;

883

seckey = arg;

836

884

break;

837

885

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

838

pubkeyname = arg;

886

pubkey = arg;

839

887

break;

840

888

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

841

889

errno = 0;

870

918

}

871

919

}

872

920

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);

921

ret = init_gnutls_global(&mc, pubkey, seckey);

888

922

if (ret == -1){

889

923

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

890

924

exitcode = EXIT_FAILURE;

892

926

} else {

893

927

gnutls_initalized = true;

894

928

}

929

930

if(mkdtemp(tempdir) == NULL){

931

perror("mkdtemp");

932

tempdir[0] = '\0';

933

goto end;

934

}

935

936

if(not init_gpgme(&mc, pubkey, seckey, tempdir)){

937

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

938

exitcode = EXIT_FAILURE;

939

goto end;

940

} else {

941

pgpme_initalized = true;

942

}

895

943

896

944

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

897

945

{

917

965

goto end;

918

966

}

919

967

}

920

close(sd);

968

ret = TEMP_FAILURE_RETRY(close(sd));

969

if(ret == -1){

970

perror("close");

971

}

921

972

}

922

973

923

974

uid = getuid();

1043

1094

1044

1095

if (mc.simple_poll != NULL)

1045

1096

avahi_simple_poll_free(mc.simple_poll);

1046

free(pubkeyfilename);

1047

free(seckeyfilename);

1048

1097

1049

1098

if (gnutls_initalized){

1050

1099

gnutls_certificate_free_credentials(mc.cred);

1051

1100

gnutls_global_deinit ();

1052

1101

}

1053

1102

1103

if(pgpme_initalized){

1104

gpgme_release(mc.ctx);

1105

}

1106

1107

/* Removes the temp directory used by GPGME */

1108

if(tempdir[0] != '\0'){

1109

DIR *d;

1110

struct dirent *direntry;

1111

d = opendir(tempdir);

1112

if(d == NULL){

1113

perror("opendir");

1114

} else {

1115

while(true){

1116

direntry = readdir(d);

1117

if(direntry == NULL){

1118

break;

1119

}

1120

if (direntry->d_type == DT_REG){

1121

char *fullname = NULL;

1122

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

1123

direntry->d_name);

1124

if(ret < 0){

1125

perror("asprintf");

1126

continue;

1127

}

1128

ret = unlink(fullname);

1129

if(ret == -1){

1130

fprintf(stderr, "unlink(\"%s\"): %s",

1131

fullname, strerror(errno));

1132

}

1133

free(fullname);

1134

}

1135

}

1136

}

1137

ret = rmdir(tempdir);

1138

if(ret == -1){

1139

perror("rmdir");

1140

}

1141

}

1142

1054

1143

return exitcode;

1055

1144

}