- /* receive welcome message */
- ret = recv_buffer(pcd->fd, buf, sizeof(buf));
- if (ret < 0)
- goto out;
- /* send auth command */
- auth_str = make_message("auth %s%s", pcd->conf.plain_given? "" : "rc4 ",
- pcd->user);
- PARA_INFO_LOG("<-- %s--> %s\n", buf, auth_str);
- ret = send_buffer(pcd->fd, auth_str);
- if (ret < 0)
- goto out;
- /* receive challenge number */
- ret = recv_buffer(pcd->fd, buf, sizeof(buf));
- if (ret < 0)
- goto out;
- if (ret != 64) {
- ret = -E_INVALID_CHALLENGE;
- PARA_ERROR_LOG("received the following: %s\n", buf);
- goto out;
- }
- PARA_INFO_LOG("%s", "<-- [challenge]\n");
- /* decrypt challenge number */
- ret = para_decrypt_challenge(pcd->key_file, &challenge_nr,
- (unsigned char *) buf, 64);
- if (ret < 0)
- goto out;
- /* send decrypted challenge */
- PARA_INFO_LOG("--> %lu\n", challenge_nr);
- ret = send_va_buffer(pcd->fd, "%s%lu", CHALLENGE_RESPONSE_MSG, challenge_nr);
- if (ret < 0)
- goto out;
- /* wait for approval */
- PARA_NOTICE_LOG("%s", "waiting for approval from server\n");
- ret = recv_buffer(pcd->fd, buf, sizeof(buf));
- if (ret < 0)
- goto out;
- numbytes = ret;
- PARA_INFO_LOG("++++ server info ++++\n%s\n++++ end of server "
- "info ++++\n", buf);
- /* check if server has sent "Proceed" message */
- ret = -E_CLIENT_AUTH;
- if (!strstr(buf, PROCEED_MSG))
- goto out;
- if (numbytes >= PROCEED_MSG_LEN + 32) {
- PARA_INFO_LOG("%s", "decrypting session key\n");
- ret = para_decrypt_buffer(pcd->key_file, rc4_buf,
- (unsigned char *)buf + PROCEED_MSG_LEN + 1,
- numbytes - PROCEED_MSG_LEN - 1);
- if (ret < 0)
- goto out;
- RC4_set_key(&pcd->rc4_send_key, RC4_KEY_LEN, rc4_buf);
- RC4_set_key(&pcd->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);
- ret = send_buffer(pcd->fd, command);
- if (ret < 0)
- goto out;
- free(command);
- command = NULL;
- ret = send_buffer(pcd->fd, EOC_MSG "\n");
- if (ret < 0)
- goto out;
- PARA_NOTICE_LOG("%s", "command sent.\n");
- received = 0;
- for (;;) {
- ret = recv_bin_buffer(pcd->fd, buf, sizeof(buf) - 1);
- if (ret <= 0) {
- if (!ret)
- PARA_NOTICE_LOG("%s", "connection closed by peer\n");
- goto out;
- }
- buf[ret] = '\0';
- numbytes = ret;
- if (!received && strstr(buf, AWAITING_DATA_MSG)) {
- ret = send_stdin(pcd->fd);
- goto out;
- }
- received = 1;
- ret = write(STDOUT_FILENO, buf, numbytes);
- if (ret != numbytes) {
- ret = -E_SHORT_CLIENT_WRITE;
- goto out;
- }
- }