- /* send auth command */
- auth_str = make_message("auth %s%s", args_info.plain_given? "" : "rc4 ",
- args_info.user_arg);
- PARA_INFO_LOG("<-- %s--> %s\n", buf, auth_str);
- if (send_buffer(sockfd, auth_str) < 0)
- exit(EXIT_FAILURE);
- /* receive challenge number */
- if ((numbytes = recv_buffer(sockfd, buf, sizeof(buf))) < 0)
- exit(EXIT_FAILURE);
- if (numbytes != 64) {
- PARA_EMERG_LOG("did not receive valid challenge (got %i bytes)\n",
- numbytes);
- buf[numbytes] = '\0';
- PARA_ERROR_LOG("received the following instead: %s\n", buf);
- exit(EXIT_FAILURE);
- }
- PARA_INFO_LOG("<-- [challenge (%i bytes)]\n", numbytes);
- /* decrypt challenge number */
- ret = para_decrypt_challenge(key_file, &challenge_nr, (unsigned char *) buf,
- numbytes);
- if (ret < 0) {
- PARA_EMERG_LOG("decrypt error (%d). Bad secret key?\n", ret);
- exit(EXIT_FAILURE);
- }
- /* send decrypted challenge */
- PARA_INFO_LOG("--> %lu\n", challenge_nr);
- if (send_va_buffer(sockfd, "%s%lu", CHALLENGE_RESPONSE_MSG, challenge_nr) < 0)
- exit(EXIT_FAILURE);
- /* Wait for approval */
- PARA_NOTICE_LOG("%s", "waiting for approval from server\n");
- if ((numbytes = recv_buffer(sockfd, buf, sizeof(buf))) < 0)
- exit(EXIT_FAILURE);
- PARA_INFO_LOG("++++ server info ++++\n%s\n++++ end of server "
- "info ++++\n", buf);
- /* Check if server has sent "Proceed" message */
- if (!strstr(buf, PROCEED_MSG)) {
- PARA_EMERG_LOG("%s", "authentication failed\n");
- exit(EXIT_FAILURE);
- }
- if (numbytes >= PROCEED_MSG_LEN + 32) {
- PARA_INFO_LOG("%s", "decrypting session key\n");
- if (para_decrypt_buffer(key_file, rc4_buf,
- (unsigned char *)buf + PROCEED_MSG_LEN + 1,
- numbytes - PROCEED_MSG_LEN - 1) < 0) {
- PARA_EMERG_LOG("%s", "error receiving rc4 key\n");
- exit(EXIT_FAILURE);
- }
- RC4_set_key(&rc4_send_key, RC4_KEY_LEN, rc4_buf);
- RC4_set_key(&rc4_recv_key, RC4_KEY_LEN, rc4_buf + RC4_KEY_LEN);
- PARA_INFO_LOG("rc4 encrytion activated: %x:%x:%x:%x\n",
- rc4_buf[0], rc4_buf[1], rc4_buf[2], rc4_buf[3]);
- crypt_function_recv = rc4_recv;
- crypt_function_send = rc4_send;
- }
- /* send command */
- PARA_INFO_LOG("--> %s\n", command);
- if (send_buffer(sockfd, command) < 0)
- exit(EXIT_FAILURE);
- free(command);
- command = NULL;
- if (send_buffer(sockfd, EOC_MSG "\n") < 0)
- exit(EXIT_FAILURE);
- PARA_NOTICE_LOG("%s", "command sent.\n");
- received = 0;
- while ((numbytes = recv_bin_buffer(sockfd, buf, sizeof(buf) - 1)) > 0) {
- buf[numbytes] = '\0';
- if (!received && strstr(buf, AWAITING_DATA_MSG)) {
- PARA_NOTICE_LOG("%s", "sending stdin\n");
- while ((ret = read(STDIN_FILENO, buf,
- sizeof(buf))) > 0) {
- if (send_bin_buffer(sockfd, buf, ret) < 0)
- break;
- }
- PARA_NOTICE_LOG("%s", "closing connection\n");
- numbytes = 1;
- break;
- }
- received = 1;
- if (write(STDOUT_FILENO, buf, numbytes) != numbytes)
- break;
- }
- if (!numbytes)
- PARA_NOTICE_LOG("%s", "connection closed by peer\n");
- close(sockfd);
- if (interactive)
- goto interactive_loop;
- return ret >= 0? 0: 1;