| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| #include "config.h" |
| #include "move-fd.h" |
| |
| /* Required for CMSG_* macros on BSD */ |
| #define __BSD_VISIBLE 1 |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <string.h> |
| #include <sys/types.h> |
| #include <sys/socket.h> |
| #include <sys/wait.h> |
| #include <unistd.h> |
| |
| int guacd_send_fd(int sock, int fd) { |
| |
| struct msghdr message = {0}; |
| char message_data[] = {'G'}; |
| |
| /* Assign data buffer */ |
| struct iovec io_vector[1]; |
| io_vector[0].iov_base = message_data; |
| io_vector[0].iov_len = sizeof(message_data); |
| message.msg_iov = io_vector; |
| message.msg_iovlen = 1; |
| |
| /* Assign ancillary data buffer */ |
| char buffer[CMSG_SPACE(sizeof(fd))]; |
| message.msg_control = buffer; |
| message.msg_controllen = sizeof(buffer); |
| |
| /* Set fields of control message header */ |
| struct cmsghdr* control = CMSG_FIRSTHDR(&message); |
| control->cmsg_level = SOL_SOCKET; |
| control->cmsg_type = SCM_RIGHTS; |
| control->cmsg_len = CMSG_LEN(sizeof(fd)); |
| |
| /* Add file descriptor to message data */ |
| memcpy(CMSG_DATA(control), &fd, sizeof(fd)); |
| |
| /* Send file descriptor */ |
| return (sendmsg(sock, &message, 0) == sizeof(message_data)); |
| |
| } |
| |
| int guacd_recv_fd(int sock) { |
| |
| int fd; |
| |
| struct msghdr message = {0}; |
| char message_data[1]; |
| |
| /* Assign data buffer */ |
| struct iovec io_vector[1]; |
| io_vector[0].iov_base = message_data; |
| io_vector[0].iov_len = sizeof(message_data); |
| message.msg_iov = io_vector; |
| message.msg_iovlen = 1; |
| |
| |
| /* Assign ancillary data buffer */ |
| char buffer[CMSG_SPACE(sizeof(fd))]; |
| message.msg_control = buffer; |
| message.msg_controllen = sizeof(buffer); |
| |
| /* Receive file descriptor */ |
| if (recvmsg(sock, &message, 0) == sizeof(message_data)) { |
| |
| /* Validate payload */ |
| if (message_data[0] != 'G') { |
| errno = EPROTO; |
| return -1; |
| } |
| |
| /* Iterate control headers, looking for the sent file descriptor */ |
| struct cmsghdr* control; |
| for (control = CMSG_FIRSTHDR(&message); control != NULL; control = CMSG_NXTHDR(&message, control)) { |
| |
| /* Pull file descriptor from data */ |
| if (control->cmsg_level == SOL_SOCKET && control->cmsg_type == SCM_RIGHTS) { |
| memcpy(&fd, CMSG_DATA(control), sizeof(fd)); |
| return fd; |
| } |
| |
| } |
| |
| } /* end if recvmsg() success */ |
| |
| /* Failed to receive file descriptor */ |
| return -1; |
| |
| } |
| |