32
32
#define _LARGEFILE_SOURCE
 
33
33
#define _FILE_OFFSET_BITS 64
 
35
 
#define _GNU_SOURCE             /* TEMP_FAILURE_RETRY() */
 
 
35
#define _GNU_SOURCE             /* TEMP_FAILURE_RETRY(), asprintf() */
 
37
 
#include <stdio.h>              /* fprintf(), stderr, fwrite(), stdout, ferror() */
 
 
37
#include <stdio.h>              /* fprintf(), stderr, fwrite(),
 
38
39
#include <stdint.h>             /* uint16_t, uint32_t */
 
39
40
#include <stddef.h>             /* NULL, size_t, ssize_t */
 
40
 
#include <stdlib.h>             /* free() */
 
 
41
#include <stdlib.h>             /* free(), EXIT_SUCCESS, EXIT_FAILURE,
 
41
43
#include <stdbool.h>            /* bool, true */
 
42
 
#include <string.h>             /* memset(), strcmp(), strlen, strerror() */
 
43
 
#include <sys/ioctl.h>          /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
 
 
44
#include <string.h>             /* memset(), strcmp(), strlen(),
 
 
45
                                   strerror(), asprintf(), strcpy() */
 
 
46
#include <sys/ioctl.h>          /* ioctl */
 
45
47
#include <sys/types.h>          /* socket(), inet_pton(), sockaddr,
 
46
 
                                   sockaddr_in6, PF_INET6, SOCK_STREAM, INET6_ADDRSTRLEN */
 
 
48
                                   sockaddr_in6, PF_INET6,
 
 
49
                                   SOCK_STREAM, INET6_ADDRSTRLEN,
 
 
50
                                   uid_t, gid_t, open(), opendir(), DIR */
 
 
51
#include <sys/stat.h>           /* open() */
 
47
52
#include <sys/socket.h>         /* socket(), struct sockaddr_in6,
 
48
53
                                   struct in6_addr, inet_pton(),
 
51
 
#include <errno.h>              /* perror() */
 
 
55
#include <fcntl.h>              /* open() */
 
 
56
#include <dirent.h>             /* opendir(), struct dirent, readdir() */
 
 
57
#include <inttypes.h>           /* PRIu16 */
 
 
58
#include <assert.h>             /* assert() */
 
 
59
#include <errno.h>              /* perror(), errno */
 
 
60
#include <time.h>               /* time() */
 
53
61
#include <net/if.h>             /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
 
54
62
                                   SIOCSIFFLAGS, if_indextoname(),
 
55
63
                                   if_nametoindex(), IF_NAMESIZE */
 
56
 
#include <unistd.h>             /* close(), SEEK_SET, off_t, write()*/
 
57
64
#include <netinet/in.h>
 
 
65
#include <unistd.h>             /* close(), SEEK_SET, off_t, write(),
 
 
66
                                   getuid(), getgid(), setuid(),
 
58
68
#include <arpa/inet.h>          /* inet_pton(), htons */
 
59
 
#include <iso646.h>             /* not */
 
60
 
#include <argp.h>               /* struct argp_option,
 
61
 
                                   struct argp_state, struct argp,
 
 
69
#include <iso646.h>             /* not, and */
 
 
70
#include <argp.h>               /* struct argp_option, error_t, struct
 
 
71
                                   argp_state, struct argp,
 
 
72
                                   argp_parse(), ARGP_KEY_ARG,
 
 
73
                                   ARGP_KEY_END, ARGP_ERR_UNKNOWN */
 
65
 
#include <avahi-core/core.h>    /* AvahiSimplePoll, AvahiServer,
 
 
76
/* All Avahi types, constants and functions
 
 
79
#include <avahi-core/core.h>
 
67
80
#include <avahi-core/lookup.h>
 
68
 
#include <avahi-core/log.h>     /* AvahiLogLevel */
 
 
81
#include <avahi-core/log.h>
 
69
82
#include <avahi-common/simple-watch.h>
 
70
83
#include <avahi-common/malloc.h>
 
71
84
#include <avahi-common/error.h>
 
74
 
#include <gnutls/gnutls.h>      /* gnutls_certificate_credentials_t,
 
78
 
                                   gnutls_global_set_log_level(),
 
79
 
                                   gnutls_global_set_log_function(),
 
80
 
                                   gnutls_certificate_allocate_credentials(),
 
81
 
                                   gnutls_global_deinit(),
 
82
 
                                   gnutls_dh_params_init(),
 
83
 
                                   gnutls_dh_params_generate(),
 
84
 
                                   gnutls_certificate_set_dh_params(),
 
85
 
                                   gnutls_certificate_free_credentials(),
 
86
 
                                   gnutls_session_t, gnutls_init(),
 
87
 
                                   gnutls_priority_set_direct(),
 
89
 
                                   gnutls_credentials_set(),
 
90
 
                                   gnutls_certificate_server_set_request(),
 
91
 
                                   gnutls_dh_set_prime_bits(),
 
92
 
                                   gnutls_transport_set_ptr(),
 
93
 
                                   gnutls_transport_ptr_t,
 
96
 
                                   gnutls_perror(), gnutls_bye(),
 
 
87
#include <gnutls/gnutls.h>      /* All GnuTLS types, constants and
 
97
90
                                   init_gnutls_session(),
 
99
 
                                   GNUTLS_CRD_CERTIFICATE,
 
101
 
                                   GNUTLS_E_INTERRUPTED,
 
103
 
                                   GNUTLS_E_REHANDSHAKE,
 
105
 
#include <gnutls/openpgp.h> /* gnutls_certificate_set_openpgp_key_file(),
 
106
 
                               GNUTLS_OPENPGP_FMT_BASE64 */
 
 
92
#include <gnutls/openpgp.h>     /* gnutls_certificate_set_openpgp_key_file(),
 
 
93
                                   GNUTLS_OPENPGP_FMT_BASE64 */
 
109
 
#include <gpgme.h>              /* gpgme_data_t, gpgme_ctx_t,
 
110
 
                                   gpgme_error_t, gpgme_engine_info_t,
 
111
 
                                   gpgme_check_version(),
 
112
 
                                   gpgme_engine_check_version(),
 
115
 
                                   gpgme_get_engine_info(),
 
116
 
                                   gpgme_set_engine_info(),
 
117
 
                                   gpgme_data_new_from_mem(),
 
118
 
                                   gpgme_data_new(), gpgme_new(),
 
120
 
                                   gpgme_decrypt_result_t,
 
121
 
                                   gpgme_op_decrypt_result(),
 
123
 
                                   gpgme_pubkey_algo_name(),
 
 
96
#include <gpgme.h>              /* All GPGME types, constants and
 
127
99
                                   GPGME_PROTOCOL_OpenPGP,
 
129
 
                                   GPG_ERR_NO_SECKEY, */
 
131
102
#define BUFFER_SIZE 256
 
 
105
  #define PATHDIR "/conf/conf.d/mandos"
 
 
108
#define PATHDIR "/conf/conf.d/mandos"
 
 
109
#define SECKEY "seckey.txt"
 
 
110
#define PUBKEY "pubkey.txt"
 
133
112
bool debug = false;
 
134
 
static const char *keydir = "/conf/conf.d/mandos";
 
135
113
static const char mandos_protocol_version[] = "1";
 
136
 
const char *argp_program_version = "mandosclient 0.9";
 
 
114
const char *argp_program_version = "password-request 1.0";
 
137
115
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
 
139
117
/* Used for passing in values through the Avahi callback functions */
 
 
167
 
 * Decrypt OpenPGP data using keyrings in HOMEDIR.
 
168
 
 * Returns -1 on error
 
170
 
static ssize_t pgp_packet_decrypt (const char *cryptotext,
 
173
 
                                   const char *homedir){
 
174
 
  gpgme_data_t dh_crypto, dh_plain;
 
 
148
static bool init_gpgme(mandos_context *mc, const char *seckey,
 
 
149
                       const char *pubkey, const char *tempdir){
 
176
151
  gpgme_error_t rc;
 
178
 
  size_t plaintext_capacity = 0;
 
179
 
  ssize_t plaintext_length = 0;
 
180
152
  gpgme_engine_info_t engine_info;
 
 
156
   * Helper function to insert pub and seckey to the enigne keyring.
 
 
158
  bool import_key(const char *filename){
 
 
160
    gpgme_data_t pgp_data;
 
 
162
    fd = TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
 
 
168
    rc = gpgme_data_new_from_fd(&pgp_data, fd);
 
 
169
    if (rc != GPG_ERR_NO_ERROR){
 
 
170
      fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
 
 
171
              gpgme_strsource(rc), gpgme_strerror(rc));
 
 
175
    rc = gpgme_op_import(mc->ctx, pgp_data);
 
 
176
    if (rc != GPG_ERR_NO_ERROR){
 
 
177
      fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
 
 
178
              gpgme_strsource(rc), gpgme_strerror(rc));
 
 
182
    ret = TEMP_FAILURE_RETRY(close(fd));
 
 
186
    gpgme_data_release(pgp_data);
 
183
 
    fprintf(stderr, "Trying to decrypt OpenPGP data\n");
 
 
191
    fprintf(stderr, "Initialize gpgme\n");
 
 
189
197
  if (rc != GPG_ERR_NO_ERROR){
 
190
198
    fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
 
191
199
            gpgme_strsource(rc), gpgme_strerror(rc));
 
195
 
  /* Set GPGME home directory for the OpenPGP engine only */
 
 
203
    /* Set GPGME home directory for the OpenPGP engine only */
 
196
204
  rc = gpgme_get_engine_info (&engine_info);
 
197
205
  if (rc != GPG_ERR_NO_ERROR){
 
198
206
    fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
 
199
207
            gpgme_strsource(rc), gpgme_strerror(rc));
 
202
210
  while(engine_info != NULL){
 
203
211
    if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
 
204
212
      gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
 
205
 
                            engine_info->file_name, homedir);
 
 
213
                            engine_info->file_name, tempdir);
 
208
216
    engine_info = engine_info->next;
 
210
218
  if(engine_info == NULL){
 
211
 
    fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
 
 
219
    fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
 
 
223
  /* Create new GPGME "context" */
 
 
224
  rc = gpgme_new(&(mc->ctx));
 
 
225
  if (rc != GPG_ERR_NO_ERROR){
 
 
226
    fprintf(stderr, "bad gpgme_new: %s: %s\n",
 
 
227
            gpgme_strsource(rc), gpgme_strerror(rc));
 
 
231
  if (not import_key(pubkey) or not import_key(seckey)){
 
 
239
 * Decrypt OpenPGP data.
 
 
240
 * Returns -1 on error
 
 
242
static ssize_t pgp_packet_decrypt (const mandos_context *mc,
 
 
243
                                   const char *cryptotext,
 
 
246
  gpgme_data_t dh_crypto, dh_plain;
 
 
249
  size_t plaintext_capacity = 0;
 
 
250
  ssize_t plaintext_length = 0;
 
 
253
    fprintf(stderr, "Trying to decrypt OpenPGP data\n");
 
215
256
  /* Create new GPGME data buffer from memory cryptotext */
 
 
233
 
  /* Create new GPGME "context" */
 
234
 
  rc = gpgme_new(&ctx);
 
235
 
  if (rc != GPG_ERR_NO_ERROR){
 
236
 
    fprintf(stderr, "bad gpgme_new: %s: %s\n",
 
237
 
            gpgme_strsource(rc), gpgme_strerror(rc));
 
238
 
    plaintext_length = -1;
 
242
274
  /* Decrypt data from the cryptotext data buffer to the plaintext
 
244
 
  rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
 
 
276
  rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
 
245
277
  if (rc != GPG_ERR_NO_ERROR){
 
246
278
    fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
 
247
279
            gpgme_strsource(rc), gpgme_strerror(rc));
 
248
280
    plaintext_length = -1;
 
 
282
      gpgme_decrypt_result_t result;
 
 
283
      result = gpgme_op_decrypt_result(mc->ctx);
 
 
285
        fprintf(stderr, "gpgme_op_decrypt_result failed\n");
 
 
287
        fprintf(stderr, "Unsupported algorithm: %s\n",
 
 
288
                result->unsupported_algorithm);
 
 
289
        fprintf(stderr, "Wrong key usage: %u\n",
 
 
290
                result->wrong_key_usage);
 
 
291
        if(result->file_name != NULL){
 
 
292
          fprintf(stderr, "File name: %s\n", result->file_name);
 
 
294
        gpgme_recipient_t recipient;
 
 
295
        recipient = result->recipients;
 
 
297
          while(recipient != NULL){
 
 
298
            fprintf(stderr, "Public key algorithm: %s\n",
 
 
299
                    gpgme_pubkey_algo_name(recipient->pubkey_algo));
 
 
300
            fprintf(stderr, "Key ID: %s\n", recipient->keyid);
 
 
301
            fprintf(stderr, "Secret key available: %s\n",
 
 
302
                    recipient->status == GPG_ERR_NO_SECKEY
 
 
304
            recipient = recipient->next;
 
249
309
    goto decrypt_end;
 
 
253
313
    fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
 
257
 
    gpgme_decrypt_result_t result;
 
258
 
    result = gpgme_op_decrypt_result(ctx);
 
260
 
      fprintf(stderr, "gpgme_op_decrypt_result failed\n");
 
262
 
      fprintf(stderr, "Unsupported algorithm: %s\n",
 
263
 
              result->unsupported_algorithm);
 
264
 
      fprintf(stderr, "Wrong key usage: %d\n",
 
265
 
              result->wrong_key_usage);
 
266
 
      if(result->file_name != NULL){
 
267
 
        fprintf(stderr, "File name: %s\n", result->file_name);
 
269
 
      gpgme_recipient_t recipient;
 
270
 
      recipient = result->recipients;
 
272
 
        while(recipient != NULL){
 
273
 
          fprintf(stderr, "Public key algorithm: %s\n",
 
274
 
                  gpgme_pubkey_algo_name(recipient->pubkey_algo));
 
275
 
          fprintf(stderr, "Key ID: %s\n", recipient->keyid);
 
276
 
          fprintf(stderr, "Secret key available: %s\n",
 
277
 
                  recipient->status == GPG_ERR_NO_SECKEY
 
279
 
          recipient = recipient->next;
 
285
316
  /* Seek back to the beginning of the GPGME plaintext data buffer */
 
286
317
  if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
 
287
318
    perror("pgpme_data_seek");
 
 
373
404
  /* OpenPGP credentials */
 
374
 
  if ((ret = gnutls_certificate_allocate_credentials (&mc->cred))
 
375
 
      != GNUTLS_E_SUCCESS) {
 
376
 
    fprintf (stderr, "GnuTLS memory error: %s\n",
 
 
405
  gnutls_certificate_allocate_credentials(&mc->cred);
 
 
406
  if (ret != GNUTLS_E_SUCCESS){
 
 
407
    fprintf (stderr, "GnuTLS memory error: %s\n", /* Spurious
 
377
409
             safer_gnutls_strerror(ret));
 
378
410
    gnutls_global_deinit ();
 
383
 
    fprintf(stderr, "Attempting to use OpenPGP certificate %s"
 
384
 
            " and keyfile %s as GnuTLS credentials\n", pubkeyfile,
 
 
415
    fprintf(stderr, "Attempting to use OpenPGP public key %s and"
 
 
416
            " secret key %s as GnuTLS credentials\n", pubkeyfilename,
 
388
420
  ret = gnutls_certificate_set_openpgp_key_file
 
389
 
    (mc->cred, pubkeyfile, seckeyfile, GNUTLS_OPENPGP_FMT_BASE64);
 
 
421
    (mc->cred, pubkeyfilename, seckeyfilename,
 
 
422
     GNUTLS_OPENPGP_FMT_BASE64);
 
390
423
  if (ret != GNUTLS_E_SUCCESS) {
 
392
425
            "Error[%d] while reading the OpenPGP key pair ('%s',"
 
393
 
            " '%s')\n", ret, pubkeyfile, seckeyfile);
 
394
 
    fprintf(stdout, "The GnuTLS error is: %s\n",
 
 
426
            " '%s')\n", ret, pubkeyfilename, seckeyfilename);
 
 
427
    fprintf(stderr, "The GnuTLS error is: %s\n",
 
395
428
            safer_gnutls_strerror(ret));
 
 
802
823
    char *connect_to = NULL;
 
 
824
    char tempdir[] = "/tmp/mandosXXXXXX";
 
803
825
    AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
 
804
 
    const char *pubkeyfile = "pubkey.txt";
 
805
 
    const char *seckeyfile = "seckey.txt";
 
 
826
    const char *seckey = PATHDIR "/" SECKEY;
 
 
827
    const char *pubkey = PATHDIR "/" PUBKEY;
 
806
829
    mandos_context mc = { .simple_poll = NULL, .server = NULL,
 
807
 
                          .dh_bits = 1024, .priority = "SECURE256"};
 
 
830
                          .dh_bits = 1024, .priority = "SECURE256"
 
 
831
                          ":!CTYPE-X.509:+CTYPE-OPENPGP" };
 
808
832
    bool gnutls_initalized = false;
 
 
833
    bool pgpme_initalized = false;
 
811
836
      struct argp_option options[] = {
 
812
837
        { .name = "debug", .key = 128,
 
813
838
          .doc = "Debug mode", .group = 3 },
 
814
839
        { .name = "connect", .key = 'c',
 
816
 
          .doc = "Connect directly to a sepcified mandos server",
 
 
840
          .arg = "ADDRESS:PORT",
 
 
841
          .doc = "Connect directly to a specific Mandos server",
 
818
843
        { .name = "interface", .key = 'i',
 
820
 
          .doc = "Interface that Avahi will conntect through",
 
822
 
        { .name = "keydir", .key = 'd',
 
824
 
          .doc = "Directory where the openpgp keyring is",
 
 
845
          .doc = "Interface that will be used to search for Mandos"
 
826
848
        { .name = "seckey", .key = 's',
 
828
 
          .doc = "Secret openpgp key for gnutls authentication",
 
 
850
          .doc = "OpenPGP secret key file base name",
 
830
852
        { .name = "pubkey", .key = 'p',
 
832
 
          .doc = "Public openpgp key for gnutls authentication",
 
 
854
          .doc = "OpenPGP public key file base name",
 
834
856
        { .name = "dh-bits", .key = 129,
 
836
 
          .doc = "dh-bits to use in gnutls communication",
 
 
858
          .doc = "Bit length of the prime number used in the"
 
 
859
          " Diffie-Hellman key exchange",
 
838
861
        { .name = "priority", .key = 130,
 
840
 
          .doc = "GNUTLS priority", .group = 1 },
 
 
863
          .doc = "GnuTLS priority string for the TLS handshake",
 
845
868
      error_t parse_opt (int key, char *arg,
 
846
869
                         struct argp_state *state) {
 
847
870
        /* Get the INPUT argument from `argp_parse', which we know is
 
848
871
           a pointer to our plugin list pointer. */
 
 
873
        case 128:               /* --debug */
 
 
876
        case 'c':               /* --connect */
 
854
877
          connect_to = arg;
 
 
879
        case 'i':               /* --interface */
 
 
882
        case 's':               /* --seckey */
 
 
885
        case 'p':               /* --pubkey */
 
 
888
        case 129:               /* --dh-bits */
 
870
890
          mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
 
 
873
893
            exit(EXIT_FAILURE);
 
 
896
        case 130:               /* --priority */
 
877
897
          mc.priority = arg;
 
879
899
        case ARGP_KEY_ARG:
 
880
900
          argp_usage (state);
 
885
904
          return ARGP_ERR_UNKNOWN;
 
890
909
      struct argp argp = { .options = options, .parser = parse_opt,
 
892
911
                           .doc = "Mandos client -- Get and decrypt"
 
893
 
                           " passwords from mandos server" };
 
894
 
      argp_parse (&argp, argc, argv, 0, 0, NULL);
 
897
 
    pubkeyfile = combinepath(keydir, pubkeyfile);
 
898
 
    if (pubkeyfile == NULL){
 
899
 
      perror("combinepath");
 
900
 
      exitcode = EXIT_FAILURE;
 
904
 
    seckeyfile = combinepath(keydir, seckeyfile);
 
905
 
    if (seckeyfile == NULL){
 
906
 
      perror("combinepath");
 
910
 
    ret = init_gnutls_global(&mc, pubkeyfile, seckeyfile);
 
912
 
      fprintf(stderr, "init_gnutls_global\n");
 
915
 
      gnutls_initalized = true;
 
 
912
                           " passwords from a Mandos server" };
 
 
913
      ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
 
 
914
      if (ret == ARGP_ERR_UNKNOWN){
 
 
915
        fprintf(stderr, "Unknown error while parsing arguments\n");
 
 
916
        exitcode = EXIT_FAILURE;
 
 
921
    /* If the interface is down, bring it up */
 
 
923
      sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
 
 
926
        exitcode = EXIT_FAILURE;
 
 
929
      strcpy(network.ifr_name, interface);
 
 
930
      ret = ioctl(sd, SIOCGIFFLAGS, &network);
 
 
932
        perror("ioctl SIOCGIFFLAGS");
 
 
933
        exitcode = EXIT_FAILURE;
 
 
936
      if((network.ifr_flags & IFF_UP) == 0){
 
 
937
        network.ifr_flags |= IFF_UP;
 
 
938
        ret = ioctl(sd, SIOCSIFFLAGS, &network);
 
 
940
          perror("ioctl SIOCSIFFLAGS");
 
 
941
          exitcode = EXIT_FAILURE;
 
 
945
      ret = TEMP_FAILURE_RETRY(close(sd));
 
921
954
    ret = setuid(uid);
 
923
956
      perror("setuid");