/mandos/trunk : revision 48

1

/* -*- coding: utf-8 -*- */

2

/*

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* Mandos-client - get and decrypt data from a Mandos server

3

* Mandos client - get and decrypt data from a Mandos server

4

*

5

* This program is partly derived from an example program for an Avahi

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* service browser, downloaded from

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* "browse_callback", and parts of "main".

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*

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* Everything else is

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13

12

14

13

*

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* This program is free software: you can redistribute it and/or

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15

* modify it under the terms of the GNU General Public License as

33

32

#define _LARGEFILE_SOURCE

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33

#define _FILE_OFFSET_BITS 64

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34

36

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

35

#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */

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36

38

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

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stdout, ferror() */

40

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

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

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

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srand() */

44

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

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

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

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

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

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, INET6_ADDRSTRLEN,

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

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

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

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struct in6_addr, inet_pton(),

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connect() */

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

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

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

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

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

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

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#include <stdio.h>

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#include <assert.h>

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#include <stdlib.h>

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#include <time.h>

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#include <net/if.h> /* if_nametoindex */

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

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SIOCSIFFLAGS */

62

44

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

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SIOCSIFFLAGS, if_indextoname(),

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if_nametoindex(), IF_NAMESIZE */

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#include <netinet/in.h>

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

67

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

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setgid() */

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

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

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

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argp_state, struct argp,

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argp_parse(), ARGP_KEY_ARG,

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ARGP_KEY_END, ARGP_ERR_UNKNOWN */

45

SIOCSIFFLAGS */

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46

76

/* Avahi */

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/* All Avahi types, constants and functions

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Avahi*, avahi_*,

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AVAHI_* */

80

47

#include <avahi-core/core.h>

81

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#include <avahi-core/lookup.h>

82

49

#include <avahi-core/log.h>

84

51

#include <avahi-common/malloc.h>

85

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#include <avahi-common/error.h>

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53

87

/* GnuTLS */

88

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

89

functions:

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gnutls_*

91

init_gnutls_session(),

92

GNUTLS_* */

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#include <gnutls/openpgp.h> /* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* Mandos client part */

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

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

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struct in6_addr, inet_pton() */

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#include <gnutls/gnutls.h> /* All GnuTLS stuff */

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#include <gnutls/openpgp.h> /* GnuTLS with openpgp stuff */

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#include <unistd.h> /* close() */

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#include <netinet/in.h>

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

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#include <string.h> /* memset */

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

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

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#include <net/if.h> /* IF_NAMESIZE */

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

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struct argp_state, struct argp,

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argp_parse() */

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/* GPGME */

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

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functions:

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gpgme_*

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GPGME_PROTOCOL_OpenPGP,

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GPG_ERR_NO_* */

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

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#include <gpgme.h>

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103

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#define BUFFER_SIZE 256

104

76

105

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

106

#define SECKEY "seckey.txt"

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#define PUBKEY "pubkey.txt"

108

109

77

bool debug = false;

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

110

79

static const char mandos_protocol_version[] = "1";

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const char *argp_program_version = "mandos-client " VERSION;

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const char *argp_program_version = "mandosclient 0.9";

112

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

113

82

114

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/* Used for passing in values through the Avahi callback functions */

119

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unsigned int dh_bits;

120

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gnutls_dh_params_t dh_params;

121

90

const char *priority;

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gpgme_ctx_t ctx;

123

91

} mandos_context;

124

92

125

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/*

140

108

}

141

109

142

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/*

143

* Initialize GPGME.

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* Decrypt OpenPGP data using keyrings in HOMEDIR.

112

* Returns -1 on error

144

113

*/

145

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

146

const char *pubkey, const char *tempdir){

147

int ret;

114

static ssize_t pgp_packet_decrypt (const char *cryptotext,

115

size_t crypto_size,

116

char **plaintext,

117

const char *homedir){

118

gpgme_data_t dh_crypto, dh_plain;

119

gpgme_ctx_t ctx;

148

120

gpgme_error_t rc;

121

ssize_t ret;

122

size_t plaintext_capacity = 0;

123

ssize_t plaintext_length = 0;

149

124

gpgme_engine_info_t engine_info;

150

125

151

152

/*

153

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

154

*/

155

bool import_key(const char *filename){

156

int fd;

157

gpgme_data_t pgp_data;

158

159

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

160

if(fd == -1){

161

perror("open");

162

return false;

163

}

164

165

rc = gpgme_data_new_from_fd(&pgp_data, fd);

166

if (rc != GPG_ERR_NO_ERROR){

167

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

168

gpgme_strsource(rc), gpgme_strerror(rc));

169

return false;

170

}

171

172

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

173

if (rc != GPG_ERR_NO_ERROR){

174

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

175

gpgme_strsource(rc), gpgme_strerror(rc));

176

return false;

177

}

178

179

ret = (int)TEMP_FAILURE_RETRY(close(fd));

180

if(ret == -1){

181

perror("close");

182

}

183

gpgme_data_release(pgp_data);

184

return true;

185

}

186

187

126

if (debug){

188

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

127

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

189

128

}

190

129

191

130

/* Init GPGME */

194

133

if (rc != GPG_ERR_NO_ERROR){

195

134

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

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gpgme_strsource(rc), gpgme_strerror(rc));

197

return false;

136

return -1;

198

137

}

199

138

200

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

139

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

201

140

rc = gpgme_get_engine_info (&engine_info);

202

141

if (rc != GPG_ERR_NO_ERROR){

203

142

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

204

143

gpgme_strsource(rc), gpgme_strerror(rc));

205

return false;

144

return -1;

206

145

}

207

146

while(engine_info != NULL){

208

147

if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){

209

148

gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,

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engine_info->file_name, tempdir);

149

engine_info->file_name, homedir);

211

150

break;

212

151

}

213

152

engine_info = engine_info->next;

214

153

}

215

154

if(engine_info == NULL){

216

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

217

return false;

218

}

219

220

/* Create new GPGME "context" */

221

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

222

if (rc != GPG_ERR_NO_ERROR){

223

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

224

gpgme_strsource(rc), gpgme_strerror(rc));

225

return false;

226

}

227

228

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

229

return false;

230

}

231

232

return true;

233

}

234

235

/*

236

* Decrypt OpenPGP data.

237

* Returns -1 on error

238

*/

239

static ssize_t pgp_packet_decrypt (const mandos_context *mc,

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const char *cryptotext,

241

size_t crypto_size,

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char **plaintext){

243

gpgme_data_t dh_crypto, dh_plain;

244

gpgme_error_t rc;

245

ssize_t ret;

246

size_t plaintext_capacity = 0;

247

ssize_t plaintext_length = 0;

248

249

if (debug){

250

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

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

156

return -1;

251

157

}

252

158

253

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

268

174

return -1;

269

175

}

270

176

177

/* Create new GPGME "context" */

178

rc = gpgme_new(&ctx);

179

if (rc != GPG_ERR_NO_ERROR){

180

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

181

gpgme_strsource(rc), gpgme_strerror(rc));

182

plaintext_length = -1;

183

goto decrypt_end;

184

}

185

271

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

272

187

data buffer */

273

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

188

rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);

274

189

if (rc != GPG_ERR_NO_ERROR){

275

190

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

276

191

gpgme_strsource(rc), gpgme_strerror(rc));

277

192

plaintext_length = -1;

278

if (debug){

279

gpgme_decrypt_result_t result;

280

result = gpgme_op_decrypt_result(mc->ctx);

281

if (result == NULL){

282

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

283

} else {

284

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

285

result->unsupported_algorithm);

286

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

287

result->wrong_key_usage);

288

if(result->file_name != NULL){

289

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

290

}

291

gpgme_recipient_t recipient;

292

recipient = result->recipients;

293

if(recipient){

294

while(recipient != NULL){

295

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

296

gpgme_pubkey_algo_name(recipient->pubkey_algo));

297

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

298

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

299

recipient->status == GPG_ERR_NO_SECKEY

300

? "No" : "Yes");

301

recipient = recipient->next;

302

}

303

}

304

}

305

}

306

193

goto decrypt_end;

307

194

}

308

195

310

197

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

311

198

}

312

199

200

if (debug){

201

gpgme_decrypt_result_t result;

202

result = gpgme_op_decrypt_result(ctx);

203

if (result == NULL){

204

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

205

} else {

206

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

207

result->unsupported_algorithm);

208

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

209

result->wrong_key_usage);

210

if(result->file_name != NULL){

211

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

212

}

213

gpgme_recipient_t recipient;

214

recipient = result->recipients;

215

if(recipient){

216

while(recipient != NULL){

217

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

218

gpgme_pubkey_algo_name(recipient->pubkey_algo));

219

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

220

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

221

recipient->status == GPG_ERR_NO_SECKEY

222

? "No" : "Yes");

223

recipient = recipient->next;

224

}

225

}

226

}

227

}

228

313

229

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

314

230

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

315

perror("gpgme_data_seek");

231

perror("pgpme_data_seek");

316

232

plaintext_length = -1;

317

233

goto decrypt_end;

318

234

}

342

258

}

343

259

plaintext_length += ret;

344

260

}

345

261

346

262

if(debug){

347

263

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

348

264

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

362

278

}

363

279

364

280

static const char * safer_gnutls_strerror (int value) {

365

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

281

const char *ret = gnutls_strerror (value);

366

282

if (ret == NULL)

367

283

ret = "(unknown)";

368

284

return ret;

375

291

}

376

292

377

293

static int init_gnutls_global(mandos_context *mc,

378

const char *pubkeyfilename,

379

const char *seckeyfilename){

294

const char *pubkeyfile,

295

const char *seckeyfile){

380

296

int ret;

381

297

382

298

if(debug){

383

299

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

384

300

}

385

386

ret = gnutls_global_init();

387

if (ret != GNUTLS_E_SUCCESS) {

301

302

if ((ret = gnutls_global_init ())

303

!= GNUTLS_E_SUCCESS) {

388

304

fprintf (stderr, "GnuTLS global_init: %s\n",

389

305

safer_gnutls_strerror(ret));

390

306

return -1;

399

315

}

400

316

401

317

/* OpenPGP credentials */

402

gnutls_certificate_allocate_credentials(&mc->cred);

403

if (ret != GNUTLS_E_SUCCESS){

404

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

405

warning */

318

if ((ret = gnutls_certificate_allocate_credentials (&mc->cred))

319

!= GNUTLS_E_SUCCESS) {

320

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

406

321

safer_gnutls_strerror(ret));

407

322

gnutls_global_deinit ();

408

323

return -1;

409

324

}

410

325

411

326

if(debug){

412

fprintf(stderr, "Attempting to use OpenPGP public key %s and"

413

" secret key %s as GnuTLS credentials\n", pubkeyfilename,

414

seckeyfilename);

327

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

328

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

329

seckeyfile);

415

330

}

416

331

417

332

ret = gnutls_certificate_set_openpgp_key_file

418

(mc->cred, pubkeyfilename, seckeyfilename,

419

GNUTLS_OPENPGP_FMT_BASE64);

333

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

420

334

if (ret != GNUTLS_E_SUCCESS) {

421

335

fprintf(stderr,

422

336

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

423

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

424

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

337

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

338

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

425

339

safer_gnutls_strerror(ret));

426

340

goto globalfail;

427

341

}

441

355

}

442

356

443

357

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

444

358

445

359

return 0;

446

360

447

361

globalfail:

448

449

gnutls_certificate_free_credentials(mc->cred);

450

gnutls_global_deinit();

451

gnutls_dh_params_deinit(mc->dh_params);

362

363

gnutls_certificate_free_credentials (mc->cred);

364

gnutls_global_deinit ();

452

365

return -1;

366

453

367

}

454

368

455

369

static int init_gnutls_session(mandos_context *mc,

501

415

AvahiIfIndex if_index,

502

416

mandos_context *mc){

503

417

int ret, tcp_sd;

504

ssize_t sret;

505

418

union { struct sockaddr in; struct sockaddr_in6 in6; } to;

506

419

char *buffer = NULL;

507

420

char *decrypted_buffer;

519

432

}

520

433

521

434

if(debug){

522

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

523

"\n", ip, port);

435

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

436

ip, port);

524

437

}

525

438

526

439

tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);

528

441

perror("socket");

529

442

return -1;

530

443

}

531

444

532

445

if(debug){

533

446

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

534

447

perror("if_indextoname");

537

450

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

538

451

}

539

452

540

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

453

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

541

454

to.in6.sin6_family = AF_INET6;

542

455

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

543

456

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

550

463

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

551

464

return -1;

552

465

}

553

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

466

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

554

467

555

468

to.in6.sin6_scope_id = (uint32_t)if_index;

556

469

557

470

if(debug){

558

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

559

port);

471

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

560

472

char addrstr[INET6_ADDRSTRLEN] = "";

561

473

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

562

474

sizeof(addrstr)) == NULL){

573

485

perror("connect");

574

486

return -1;

575

487

}

576

488

577

489

const char *out = mandos_protocol_version;

578

490

written = 0;

579

491

while (true){

580

492

size_t out_size = strlen(out);

581

ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,

493

ret = TEMP_FAILURE_RETRY(write(tcp_sd, out + written,

582

494

out_size - written));

583

495

if (ret == -1){

584

496

perror("write");

597

509

}

598

510

}

599

511

}

600

512

601

513

if(debug){

602

514

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

603

515

}

604

516

605

517

gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);

606

518

607

do{

608

ret = gnutls_handshake (session);

609

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

519

ret = gnutls_handshake (session);

610

520

611

521

if (ret != GNUTLS_E_SUCCESS){

612

522

if(debug){

623

533

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

624

534

ip);

625

535

}

626

536

627

537

while(true){

628

538

buffer_capacity = adjustbuffer(&buffer, buffer_length,

629

539

buffer_capacity);

633

543

goto mandos_end;

634

544

}

635

545

636

sret = gnutls_record_recv(session, buffer+buffer_length,

637

BUFFER_SIZE);

638

if (sret == 0){

546

ret = gnutls_record_recv(session, buffer+buffer_length,

547

BUFFER_SIZE);

548

if (ret == 0){

639

549

break;

640

550

}

641

if (sret < 0){

642

switch(sret){

551

if (ret < 0){

552

switch(ret){

643

553

case GNUTLS_E_INTERRUPTED:

644

554

case GNUTLS_E_AGAIN:

645

555

break;

646

556

case GNUTLS_E_REHANDSHAKE:

647

do{

648

ret = gnutls_handshake (session);

649

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

557

ret = gnutls_handshake (session);

650

558

if (ret < 0){

651

559

fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");

652

560

gnutls_perror (ret);

662

570

goto mandos_end;

663

571

}

664

572

} else {

665

buffer_length += (size_t) sret;

573

buffer_length += (size_t) ret;

666

574

}

667

575

}

668

576

673

581

gnutls_bye (session, GNUTLS_SHUT_RDWR);

674

582

675

583

if (buffer_length > 0){

676

decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,

584

decrypted_buffer_size = pgp_packet_decrypt(buffer,

677

585

buffer_length,

678

&decrypted_buffer);

586

&decrypted_buffer,

587

keydir);

679

588

if (decrypted_buffer_size >= 0){

680

589

written = 0;

681

590

while(written < (size_t) decrypted_buffer_size){

696

605

} else {

697

606

retval = -1;

698

607

}

699

} else {

700

retval = -1;

701

608

}

702

609

703

610

/* Shutdown procedure */

704

611

705

612

mandos_end:

706

613

free(buffer);

707

ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));

708

if(ret == -1){

709

perror("close");

710

}

614

close(tcp_sd);

711

615

gnutls_deinit (session);

712

616

return retval;

713

617

}

727

631

flags,

728

632

void* userdata) {

729

633

mandos_context *mc = userdata;

730

assert(r);

634

assert(r); /* Spurious warning */

731

635

732

636

/* Called whenever a service has been resolved successfully or

733

637

timed out */

745

649

char ip[AVAHI_ADDRESS_STR_MAX];

746

650

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

747

651

if(debug){

748

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

749

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

750

interface, port);

652

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

653

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

751

654

}

752

655

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

753

656

if (ret == 0){

754

avahi_simple_poll_quit(mc->simple_poll);

657

exit(EXIT_SUCCESS);

755

658

}

756

659

}

757

660

}

769

672

flags,

770

673

void* userdata) {

771

674

mandos_context *mc = userdata;

772

assert(b);

675

assert(b); /* Spurious warning */

773

676

774

677

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

775

678

is removed from the LAN */

809

712

}

810

713

}

811

714

715

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

716

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

717

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

718

size_t f_len = strlen(first);

719

size_t s_len = strlen(second);

720

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

721

if (tmp == NULL){

722

return NULL;

723

}

724

if(f_len > 0){

725

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

726

}

727

tmp[f_len] = '/';

728

if(s_len > 0){

729

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

730

}

731

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

732

return tmp;

733

}

734

735

812

736

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

813

737

AvahiSServiceBrowser *sb = NULL;

814

738

int error;

820

744

uid_t uid;

821

745

gid_t gid;

822

746

char *connect_to = NULL;

823

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

824

747

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

825

const char *seckey = PATHDIR "/" SECKEY;

826

const char *pubkey = PATHDIR "/" PUBKEY;

827

748

const char *pubkeyfile = "pubkey.txt";

749

const char *seckeyfile = "seckey.txt";

828

750

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

829

.dh_bits = 1024, .priority = "SECURE256"

830

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

751

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

831

752

bool gnutls_initalized = false;

832

bool gpgme_initalized = false;

833

753

834

754

{

835

755

struct argp_option options[] = {

836

756

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

837

757

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

838

758

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

839

.arg = "ADDRESS:PORT",

840

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

759

.arg = "IP",

760

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

841

761

.group = 1 },

842

762

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

843

.arg = "NAME",

844

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

845

" servers",

763

.arg = "INTERFACE",

764

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

765

.group = 1 },

766

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

767

.arg = "KEYDIR",

768

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

846

769

.group = 1 },

847

770

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

848

.arg = "FILE",

849

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

771

.arg = "SECKEY",

772

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

850

773

.group = 1 },

851

774

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

852

.arg = "FILE",

853

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

775

.arg = "PUBKEY",

776

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

854

777

.group = 2 },

855

778

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

856

779

.arg = "BITS",

857

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

858

" Diffie-Hellman key exchange",

780

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

859

781

.group = 2 },

860

782

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

861

.arg = "STRING",

862

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

863

.group = 1 },

783

.arg = "PRIORITY",

784

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

864

785

{ .name = NULL }

865

786

};

787

866

788

867

789

error_t parse_opt (int key, char *arg,

868

790

struct argp_state *state) {

869

791

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

870

792

a pointer to our plugin list pointer. */

871

793

switch (key) {

872

case 128: /* --debug */

794

case 128:

873

795

debug = true;

874

796

break;

875

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

797

case 'c':

876

798

connect_to = arg;

877

799

break;

878

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

800

case 'i':

879

801

interface = arg;

880

802

break;

881

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

882

seckey = arg;

883

break;

884

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

885

pubkey = arg;

886

break;

887

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

803

case 'd':

804

keydir = arg;

805

break;

806

case 's':

807

seckeyfile = arg;

808

break;

809

case 'p':

810

pubkeyfile = arg;

811

break;

812

case 129:

888

813

errno = 0;

889

814

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

890

815

if (errno){

892

817

exit(EXIT_FAILURE);

893

818

}

894

819

break;

895

case 130: /* --priority */

820

case 130:

896

821

mc.priority = arg;

897

822

break;

898

823

case ARGP_KEY_ARG:

899

824

argp_usage (state);

900

case ARGP_KEY_END:

901

825

break;

826

case ARGP_KEY_END:

827

break;

902

828

default:

903

829

return ARGP_ERR_UNKNOWN;

904

830

}

905

831

return 0;

906

832

}

907

833

908

834

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

909

835

.args_doc = "",

910

836

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

911

" passwords from a Mandos server" };

912

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

913

if (ret == ARGP_ERR_UNKNOWN){

914

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

915

exitcode = EXIT_FAILURE;

916

goto end;

917

}

918

}

919

920

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

921

{

922

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

923

if(sd < 0) {

924

perror("socket");

925

exitcode = EXIT_FAILURE;

926

goto end;

927

}

928

strcpy(network.ifr_name, interface);

929

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

930

if(ret == -1){

931

perror("ioctl SIOCGIFFLAGS");

932

exitcode = EXIT_FAILURE;

933

goto end;

934

}

935

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

936

network.ifr_flags |= IFF_UP;

937

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

938

if(ret == -1){

939

perror("ioctl SIOCSIFFLAGS");

940

exitcode = EXIT_FAILURE;

941

goto end;

942

}

943

}

944

ret = (int)TEMP_FAILURE_RETRY(close(sd));

945

if(ret == -1){

946

perror("close");

947

}

948

}

949

837

" passwords from mandos server" };

838

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

839

}

840

841

pubkeyfile = combinepath(keydir, pubkeyfile);

842

if (pubkeyfile == NULL){

843

perror("combinepath");

844

exitcode = EXIT_FAILURE;

845

goto end;

846

}

847

848

seckeyfile = combinepath(keydir, seckeyfile);

849

if (seckeyfile == NULL){

850

perror("combinepath");

851

goto end;

852

}

853

854

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

855

if (ret == -1){

856

fprintf(stderr, "init_gnutls_global\n");

857

goto end;

858

} else {

859

gnutls_initalized = true;

860

}

861

950

862

uid = getuid();

951

863

gid = getgid();

952

864

953

865

ret = setuid(uid);

954

866

if (ret == -1){

955

867

perror("setuid");

960

872

perror("setgid");

961

873

}

962

874

963

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

964

if (ret == -1){

965

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

966

exitcode = EXIT_FAILURE;

967

goto end;

968

} else {

969

gnutls_initalized = true;

970

}

971

972

if(mkdtemp(tempdir) == NULL){

973

perror("mkdtemp");

974

tempdir[0] = '\0';

975

goto end;

976

}

977

978

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

979

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

980

exitcode = EXIT_FAILURE;

981

goto end;

982

} else {

983

gpgme_initalized = true;

984

}

985

986

875

if_index = (AvahiIfIndex) if_nametoindex(interface);

987

876

if(if_index == 0){

988

877

fprintf(stderr, "No such interface: \"%s\"\n", interface);

1016

905

goto end;

1017

906

}

1018

907

908

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

909

{

910

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

911

if(sd < 0) {

912

perror("socket");

913

exitcode = EXIT_FAILURE;

914

goto end;

915

}

916

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

917

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

918

if(ret == -1){

919

perror("ioctl SIOCGIFFLAGS");

920

exitcode = EXIT_FAILURE;

921

goto end;

922

}

923

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

924

network.ifr_flags |= IFF_UP;

925

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

926

if(ret == -1){

927

perror("ioctl SIOCSIFFLAGS");

928

exitcode = EXIT_FAILURE;

929

goto end;

930

}

931

}

932

close(sd);

933

}

934

1019

935

if (not debug){

1020

936

avahi_set_log_function(empty_log);

1021

937

}

1031

947

exitcode = EXIT_FAILURE;

1032

948

goto end;

1033

949

}

1034

950

1035

951

{

1036

952

AvahiServerConfig config;

1037

953

/* Do not publish any local Zeroconf records */

1040

956

config.publish_addresses = 0;

1041

957

config.publish_workstation = 0;

1042

958

config.publish_domain = 0;

1043

959

1044

960

/* Allocate a new server */

1045

961

mc.server = avahi_server_new(avahi_simple_poll_get

1046

962

(mc.simple_poll), &config, NULL,

1047

963

NULL, &error);

1048

964

1049

965

/* Free the Avahi configuration data */

1050

966

avahi_server_config_free(&config);

1051

967

}

1071

987

}

1072

988

1073

989

/* Run the main loop */

1074

990

1075

991

if (debug){

1076

992

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

1077

993

}

1079

995

avahi_simple_poll_loop(mc.simple_poll);

1080

996

1081

997

end:

1082

998

1083

999

if (debug){

1084

1000

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

1085

1001

}

1090

1006

1091

1007

if (mc.server != NULL)

1092

1008

avahi_server_free(mc.server);

1093

1009

1094

1010

if (mc.simple_poll != NULL)

1095

1011

avahi_simple_poll_free(mc.simple_poll);

1096

1012

free(pubkeyfile);

1013

free(seckeyfile);

1014

1097

1015

if (gnutls_initalized){

1098

gnutls_certificate_free_credentials(mc.cred);

1016

gnutls_certificate_free_credentials (mc.cred);

1099

1017

gnutls_global_deinit ();

1100

gnutls_dh_params_deinit(mc.dh_params);

1101

}

1102

1103

if(gpgme_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

closedir(d);

1137

}

1138

ret = rmdir(tempdir);

1139

if(ret == -1){

1140

perror("rmdir");

1141

}

1142

}

1143

1018

}

1019

1144

1020

return exitcode;

1145

1021

}