32
33
#define _LARGEFILE_SOURCE
33
34
#define _FILE_OFFSET_BITS 64
35
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */
36
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
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#include <stdio.h> /* fprintf(), stderr, fwrite(), stdout,
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#include <stdio.h> /* fprintf(), stderr, fwrite(),
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stdout, ferror(), sscanf */
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#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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#include <stdbool.h> /* bool, true */
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45
#include <string.h> /* memset(), strcmp(), strlen(),
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strerror(), memcpy(), strcpy() */
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strerror(), asprintf(), strcpy() */
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#include <sys/ioctl.h> /* ioctl */
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#include <net/if.h> /* ifreq, SIOCGIFFLAGS, SIOCSIFFLAGS,
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48
#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(), 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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#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>
63
66
#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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71
#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,
135
* 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,
146
const char *pubkey, const char *tempdir){
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148
gpgme_error_t rc;
146
size_t plaintext_capacity = 0;
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ssize_t plaintext_length = 0;
148
149
gpgme_engine_info_t engine_info;
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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, "Trying to decrypt OpenPGP data\n");
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fprintf(stderr, "Initialize gpgme\n");
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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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/* 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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207
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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213
engine_info = engine_info->next;
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215
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
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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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/* 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;
210
271
/* 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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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(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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result->unsupported_algorithm);
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fprintf(stderr, "Wrong key usage: %u\n",
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result->wrong_key_usage);
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if(result->file_name != NULL){
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fprintf(stderr, "File name: %s\n", result->file_name);
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gpgme_recipient_t recipient;
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recipient = result->recipients;
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while(recipient != NULL){
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fprintf(stderr, "Public key algorithm: %s\n",
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gpgme_pubkey_algo_name(recipient->pubkey_algo));
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fprintf(stderr, "Key ID: %s\n", recipient->keyid);
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fprintf(stderr, "Secret key available: %s\n",
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recipient->status == GPG_ERR_NO_SECKEY
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recipient = recipient->next;
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goto decrypt_end;
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fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
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gpgme_decrypt_result_t result;
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result = gpgme_op_decrypt_result(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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result->unsupported_algorithm);
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fprintf(stderr, "Wrong key usage: %u\n",
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result->wrong_key_usage);
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if(result->file_name != NULL){
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fprintf(stderr, "File name: %s\n", result->file_name);
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gpgme_recipient_t recipient;
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recipient = result->recipients;
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while(recipient != NULL){
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fprintf(stderr, "Public key algorithm: %s\n",
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gpgme_pubkey_algo_name(recipient->pubkey_algo));
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fprintf(stderr, "Key ID: %s\n", recipient->keyid);
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fprintf(stderr, "Secret key available: %s\n",
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recipient->status == GPG_ERR_NO_SECKEY
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recipient = recipient->next;
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/* Seek back to the beginning of the GPGME plaintext data buffer */
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if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
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perror("pgpme_data_seek");
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perror("gpgme_data_seek");
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plaintext_length = -1;
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317
goto decrypt_end;
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401
/* OpenPGP credentials */
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402
gnutls_certificate_allocate_credentials(&mc->cred);
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403
if (ret != GNUTLS_E_SUCCESS){
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fprintf (stderr, "GnuTLS memory error: %s\n",
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fprintf (stderr, "GnuTLS memory error: %s\n", /* Spurious
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406
safer_gnutls_strerror(ret));
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407
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", pubkeyfile,
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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, pubkeyfile, seckeyfile, GNUTLS_OPENPGP_FMT_BASE64);
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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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422
"Error[%d] while reading the OpenPGP key pair ('%s',"
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" '%s')\n", ret, pubkeyfile, seckeyfile);
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fprintf(stdout, "The GnuTLS error is: %s\n",
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" '%s')\n", ret, pubkeyfilename, seckeyfilename);
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fprintf(stderr, "The GnuTLS error is: %s\n",
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safer_gnutls_strerror(ret));
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822
char *connect_to = NULL;
823
char tempdir[] = "/tmp/mandosXXXXXX";
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824
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
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const char *pubkeyfile = "pubkey.txt";
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const char *seckeyfile = "seckey.txt";
825
const char *seckey = PATHDIR "/" SECKEY;
826
const char *pubkey = PATHDIR "/" PUBKEY;
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828
mandos_context mc = { .simple_poll = NULL, .server = NULL,
781
.dh_bits = 1024, .priority = "SECURE256"};
829
.dh_bits = 1024, .priority = "SECURE256"
830
":!CTYPE-X.509:+CTYPE-OPENPGP" };
782
831
bool gnutls_initalized = false;
832
bool gpgme_initalized = false;
785
835
struct argp_option options[] = {
786
836
{ .name = "debug", .key = 128,
787
837
.doc = "Debug mode", .group = 3 },
788
838
{ .name = "connect", .key = 'c',
790
.doc = "Connect directly to a sepcified mandos server",
839
.arg = "ADDRESS:PORT",
840
.doc = "Connect directly to a specific Mandos server",
792
842
{ .name = "interface", .key = 'i',
794
.doc = "Interface that Avahi will conntect through",
796
{ .name = "keydir", .key = 'd',
798
.doc = "Directory where the openpgp keyring is",
844
.doc = "Interface that will be used to search for Mandos"
800
847
{ .name = "seckey", .key = 's',
802
.doc = "Secret openpgp key for gnutls authentication",
849
.doc = "OpenPGP secret key file base name",
804
851
{ .name = "pubkey", .key = 'p',
806
.doc = "Public openpgp key for gnutls authentication",
853
.doc = "OpenPGP public key file base name",
808
855
{ .name = "dh-bits", .key = 129,
810
.doc = "dh-bits to use in gnutls communication",
857
.doc = "Bit length of the prime number used in the"
858
" Diffie-Hellman key exchange",
812
860
{ .name = "priority", .key = 130,
814
.doc = "GNUTLS priority", .group = 1 },
862
.doc = "GnuTLS priority string for the TLS handshake",
819
867
error_t parse_opt (int key, char *arg,
820
868
struct argp_state *state) {
821
/* Get the INPUT argument from `argp_parse', which we know is
822
a pointer to our plugin list pointer. */
870
case 128: /* --debug */
873
case 'c': /* --connect */
828
874
connect_to = arg;
876
case 'i': /* --interface */
844
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
879
case 's': /* --seckey */
882
case 'p': /* --pubkey */
885
case 129: /* --dh-bits */
886
ret = sscanf(arg, "%u", &mc.dh_bits);
887
if(ret == 0 or mc.dh_bits == 0){
888
fprintf(stderr, "Bad number of DH bits\n");
847
889
exit(EXIT_FAILURE);
892
case 130: /* --priority */
851
893
mc.priority = arg;
853
895
case ARGP_KEY_ARG:
854
896
argp_usage (state);
859
900
return ARGP_ERR_UNKNOWN;
864
905
struct argp argp = { .options = options, .parser = parse_opt,
866
907
.doc = "Mandos client -- Get and decrypt"
867
" passwords from mandos server" };
908
" passwords from a Mandos server" };
868
909
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
869
910
if (ret == ARGP_ERR_UNKNOWN){
870
fprintf(stderr, "Unkown error while parsing arguments\n");
871
exitcode = EXIT_FAILURE;
876
pubkeyfile = combinepath(keydir, pubkeyfile);
877
if (pubkeyfile == NULL){
878
perror("combinepath");
879
exitcode = EXIT_FAILURE;
883
seckeyfile = combinepath(keydir, seckeyfile);
884
if (seckeyfile == NULL){
885
perror("combinepath");
889
ret = init_gnutls_global(&mc, pubkeyfile, seckeyfile);
891
fprintf(stderr, "init_gnutls_global\n");
894
gnutls_initalized = true;
911
fprintf(stderr, "Unknown error while parsing arguments\n");
912
exitcode = EXIT_FAILURE;
917
/* If the interface is down, bring it up */
919
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
922
exitcode = EXIT_FAILURE;
925
strcpy(network.ifr_name, interface);
926
ret = ioctl(sd, SIOCGIFFLAGS, &network);
928
perror("ioctl SIOCGIFFLAGS");
929
exitcode = EXIT_FAILURE;
932
if((network.ifr_flags & IFF_UP) == 0){
933
network.ifr_flags |= IFF_UP;
934
ret = ioctl(sd, SIOCSIFFLAGS, &network);
936
perror("ioctl SIOCSIFFLAGS");
937
exitcode = EXIT_FAILURE;
941
ret = (int)TEMP_FAILURE_RETRY(close(sd));
900
950
ret = setuid(uid);
902
952
perror("setuid");