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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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#include <inttypes.h> /* PRIu16 */
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uid_t, gid_t, open(), opendir(),
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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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#include <fcntl.h> /* open() */
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#include <dirent.h> /* opendir(), struct dirent, readdir()
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#include <inttypes.h> /* PRIu16, SCNu16 */
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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 <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(),
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getuid(), getgid(), setuid(),
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#include <netinet/in.h>
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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 <iso646.h> /* not, and, or */
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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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* Decrypt OpenPGP data using keyrings in HOMEDIR.
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* Returns -1 on error
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static ssize_t pgp_packet_decrypt (const char *cryptotext,
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const char *homedir){
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gpgme_data_t dh_crypto, dh_plain;
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static bool init_gpgme(mandos_context *mc, const char *seckey,
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const char *pubkey, const char *tempdir){
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gpgme_error_t rc;
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size_t plaintext_capacity = 0;
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ssize_t plaintext_length = 0;
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gpgme_engine_info_t engine_info;
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fprintf(stderr, "Trying to decrypt OpenPGP data\n");
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* Helper function to insert pub and seckey to the enigne keyring.
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bool import_key(const char *filename){
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gpgme_data_t pgp_data;
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fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
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rc = gpgme_data_new_from_fd(&pgp_data, fd);
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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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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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ret = (int)TEMP_FAILURE_RETRY(close(fd));
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gpgme_data_release(pgp_data);
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fprintf(stderr, "Initialize gpgme\n");
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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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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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/* 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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/* 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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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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engine_info = engine_info->next;
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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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fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
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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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if(not import_key(pubkey) or not import_key(seckey)){
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* Decrypt OpenPGP data.
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* Returns -1 on error
242
static ssize_t pgp_packet_decrypt(const mandos_context *mc,
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const char *cryptotext,
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gpgme_data_t dh_crypto, dh_plain;
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size_t plaintext_capacity = 0;
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ssize_t plaintext_length = 0;
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fprintf(stderr, "Trying to decrypt OpenPGP data\n");
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/* Create new GPGME data buffer from memory cryptotext */
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rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
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if (rc != GPG_ERR_NO_ERROR){
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if(rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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/* Create new empty GPGME data buffer for the plaintext */
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rc = gpgme_data_new(&dh_plain);
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if (rc != GPG_ERR_NO_ERROR){
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if(rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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gpgme_data_release(dh_crypto);
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/* Create new GPGME "context" */
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rc = gpgme_new(&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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plaintext_length = -1;
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/* Decrypt data from the cryptotext data buffer to the plaintext
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rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
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if (rc != GPG_ERR_NO_ERROR){
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rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
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if(rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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plaintext_length = -1;
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gpgme_decrypt_result_t result;
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result = gpgme_op_decrypt_result(ctx);
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result = gpgme_op_decrypt_result(mc->ctx);
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fprintf(stderr, "gpgme_op_decrypt_result failed\n");
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fprintf(stderr, "Unsupported algorithm: %s\n",
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/* OpenPGP credentials */
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gnutls_certificate_allocate_credentials(&mc->cred);
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if (ret != GNUTLS_E_SUCCESS){
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fprintf (stderr, "GnuTLS memory error: %s\n", /* Spurious
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safer_gnutls_strerror(ret));
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gnutls_global_deinit ();
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if(ret != GNUTLS_E_SUCCESS){
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fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
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safer_gnutls_strerror(ret));
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gnutls_global_deinit();
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fprintf(stderr, "Attempting to use OpenPGP certificate %s"
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" and keyfile %s as GnuTLS credentials\n", pubkeyfilename,
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fprintf(stderr, "Attempting to use OpenPGP public key %s and"
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" secret key %s as GnuTLS credentials\n", pubkeyfilename,
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ret = gnutls_certificate_set_openpgp_key_file
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(mc->cred, pubkeyfilename, seckeyfilename,
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GNUTLS_OPENPGP_FMT_BASE64);
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if (ret != GNUTLS_E_SUCCESS) {
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if(ret != GNUTLS_E_SUCCESS) {
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"Error[%d] while reading the OpenPGP key pair ('%s',"
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" '%s')\n", ret, pubkeyfilename, seckeyfilename);
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fprintf(stdout, "The GnuTLS error is: %s\n",
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fprintf(stderr, "The GnuTLS error is: %s\n",
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431
safer_gnutls_strerror(ret));
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/* GnuTLS server initialization */
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ret = gnutls_dh_params_init(&mc->dh_params);
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if (ret != GNUTLS_E_SUCCESS) {
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fprintf (stderr, "Error in GnuTLS DH parameter initialization:"
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" %s\n", safer_gnutls_strerror(ret));
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if(ret != GNUTLS_E_SUCCESS) {
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fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
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" %s\n", safer_gnutls_strerror(ret));
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ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
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if (ret != GNUTLS_E_SUCCESS) {
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fprintf (stderr, "Error in GnuTLS prime generation: %s\n",
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safer_gnutls_strerror(ret));
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if(ret != GNUTLS_E_SUCCESS) {
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fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
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safer_gnutls_strerror(ret));
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ret = gnutls_priority_set_direct(*session, mc->priority, &err);
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if (ret != GNUTLS_E_SUCCESS) {
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if(ret != GNUTLS_E_SUCCESS) {
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fprintf(stderr, "Syntax error at: %s\n", err);
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fprintf(stderr, "GnuTLS error: %s\n",
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safer_gnutls_strerror(ret));
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gnutls_deinit (*session);
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gnutls_deinit(*session);
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ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
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if (ret != GNUTLS_E_SUCCESS) {
485
if(ret != GNUTLS_E_SUCCESS) {
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fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
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487
safer_gnutls_strerror(ret));
420
gnutls_deinit (*session);
488
gnutls_deinit(*session);
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/* ignore client certificate if any. */
425
gnutls_certificate_server_set_request (*session,
493
gnutls_certificate_server_set_request(*session,
428
gnutls_dh_set_prime_bits (*session, mc->dh_bits);
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gnutls_dh_set_prime_bits(*session, mc->dh_bits);
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636
buffer_capacity = adjustbuffer(&buffer, buffer_length,
566
637
buffer_capacity);
567
if (buffer_capacity == 0){
638
if(buffer_capacity == 0){
568
639
perror("adjustbuffer");
573
ret = gnutls_record_recv(session, buffer+buffer_length,
644
sret = gnutls_record_recv(session, buffer+buffer_length,
580
651
case GNUTLS_E_INTERRUPTED:
581
652
case GNUTLS_E_AGAIN:
583
654
case GNUTLS_E_REHANDSHAKE:
585
ret = gnutls_handshake (session);
656
ret = gnutls_handshake(session);
586
657
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
588
659
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
607
678
fprintf(stderr, "Closing TLS session\n");
610
gnutls_bye (session, GNUTLS_SHUT_RDWR);
681
gnutls_bye(session, GNUTLS_SHUT_RDWR);
612
if (buffer_length > 0){
613
decrypted_buffer_size = pgp_packet_decrypt(buffer,
683
if(buffer_length > 0){
684
decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,
617
if (decrypted_buffer_size >= 0){
687
if(decrypted_buffer_size >= 0){
619
689
while(written < (size_t) decrypted_buffer_size){
620
ret = (int)fwrite (decrypted_buffer + written, 1,
621
(size_t)decrypted_buffer_size - written,
690
ret = (int)fwrite(decrypted_buffer + written, 1,
691
(size_t)decrypted_buffer_size - written,
623
693
if(ret == 0 and ferror(stdout)){
625
695
fprintf(stderr, "Error writing encrypted data: %s\n",
769
830
char *connect_to = NULL;
831
char tempdir[] = "/tmp/mandosXXXXXX";
770
832
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";
833
const char *seckey = PATHDIR "/" SECKEY;
834
const char *pubkey = PATHDIR "/" PUBKEY;
775
836
mandos_context mc = { .simple_poll = NULL, .server = NULL,
776
837
.dh_bits = 1024, .priority = "SECURE256"
777
838
":!CTYPE-X.509:+CTYPE-OPENPGP" };
778
839
bool gnutls_initalized = false;
840
bool gpgme_initalized = false;
781
843
struct argp_option options[] = {
863
915
.doc = "Mandos client -- Get and decrypt"
864
916
" passwords from a Mandos server" };
865
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
866
if (ret == ARGP_ERR_UNKNOWN){
917
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
918
if(ret == ARGP_ERR_UNKNOWN){
867
919
fprintf(stderr, "Unknown error while parsing arguments\n");
868
920
exitcode = EXIT_FAILURE;
873
pubkeyfilename = combinepath(keydir, pubkeyname);
874
if (pubkeyfilename == NULL){
875
perror("combinepath");
876
exitcode = EXIT_FAILURE;
880
seckeyfilename = combinepath(keydir, seckeyname);
881
if (seckeyfilename == NULL){
882
perror("combinepath");
883
exitcode = EXIT_FAILURE;
887
ret = init_gnutls_global(&mc, pubkeyfilename, seckeyfilename);
889
fprintf(stderr, "init_gnutls_global failed\n");
890
exitcode = EXIT_FAILURE;
893
gnutls_initalized = true;
896
925
/* If the interface is down, bring it up */
898
927
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
949
ret = (int)TEMP_FAILURE_RETRY(close(sd));
926
958
ret = setuid(uid);
928
960
perror("setuid");
933
965
perror("setgid");
968
ret = init_gnutls_global(&mc, pubkey, seckey);
970
fprintf(stderr, "init_gnutls_global failed\n");
971
exitcode = EXIT_FAILURE;
974
gnutls_initalized = true;
977
if(mkdtemp(tempdir) == NULL){
983
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
984
fprintf(stderr, "gpgme_initalized failed\n");
985
exitcode = EXIT_FAILURE;
988
gpgme_initalized = true;
936
991
if_index = (AvahiIfIndex) if_nametoindex(interface);
937
992
if(if_index == 0){
938
993
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1034
1089
fprintf(stderr, "%s exiting\n", argv[0]);
1037
1092
/* Cleanup things */
1039
1094
avahi_s_service_browser_free(sb);
1041
if (mc.server != NULL)
1096
if(mc.server != NULL)
1042
1097
avahi_server_free(mc.server);
1044
if (mc.simple_poll != NULL)
1099
if(mc.simple_poll != NULL)
1045
1100
avahi_simple_poll_free(mc.simple_poll);
1046
free(pubkeyfilename);
1047
free(seckeyfilename);
1049
if (gnutls_initalized){
1102
if(gnutls_initalized){
1050
1103
gnutls_certificate_free_credentials(mc.cred);
1051
gnutls_global_deinit ();
1104
gnutls_global_deinit();
1105
gnutls_dh_params_deinit(mc.dh_params);
1108
if(gpgme_initalized){
1109
gpgme_release(mc.ctx);
1112
/* Removes the temp directory used by GPGME */
1113
if(tempdir[0] != '\0'){
1115
struct dirent *direntry;
1116
d = opendir(tempdir);
1118
if(errno != ENOENT){
1123
direntry = readdir(d);
1124
if(direntry == NULL){
1127
if(direntry->d_type == DT_REG){
1128
char *fullname = NULL;
1129
ret = asprintf(&fullname, "%s/%s", tempdir,
1135
ret = unlink(fullname);
1137
fprintf(stderr, "unlink(\"%s\"): %s",
1138
fullname, strerror(errno));
1145
ret = rmdir(tempdir);
1146
if(ret == -1 and errno != ENOENT){
1054
1151
return exitcode;