1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <netinet/in.h> 30 31 #include <errno.h> 32 #include <netdb.h> 33 #include <sys/types.h> 34 #include <sys/socket.h> 35 #include <string.h> 36 #include <unistd.h> 37 38 constexpr int START_PORT = 600; 39 constexpr int END_PORT = IPPORT_RESERVED; 40 constexpr int NUM_PORTS = (END_PORT - START_PORT); 41 42 int bindresvport(int sd, struct sockaddr_in* sin) { 43 sockaddr_in sin0; 44 if (sin == nullptr) { 45 memset(&sin0, 0, sizeof(sin0)); 46 sin = &sin0; 47 sin->sin_family = AF_INET; 48 } 49 50 if (sin->sin_family != AF_INET) { 51 errno = EPFNOSUPPORT; 52 return -1; 53 } 54 55 // TODO: thread safety! 56 static short port; 57 if (port == 0) { 58 port = START_PORT + (getpid() % NUM_PORTS); 59 } 60 61 for (size_t i = NUM_PORTS; i > 0; i--, port++) { 62 if (port == END_PORT) port = START_PORT; 63 sin->sin_port = htons(port); 64 int rc = TEMP_FAILURE_RETRY(bind(sd, reinterpret_cast<sockaddr*>(sin), sizeof(*sin))); 65 if (rc >= 0) return rc; 66 } 67 return -1; 68 } 69 70 const in6_addr in6addr_any = IN6ADDR_ANY_INIT; 71 const in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT; 72
