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 #include <errno.h> 29 #include <sys/types.h> 30 #include <sys/socket.h> 31 #include <netinet/in.h> 32 #include <string.h> 33 #include <unistd.h> 34 35 #define START_PORT 600 36 #define END_PORT IPPORT_RESERVED 37 #define NUM_PORTS (END_PORT - START_PORT) 38 39 int bindresvport(int sd, struct sockaddr_in *sin) 40 { 41 static short port; 42 struct sockaddr_in sin0; 43 int nn, ret; 44 45 if (sin == NULL) { 46 sin = &sin0; 47 memset( sin, 0, sizeof *sin ); 48 sin->sin_family = AF_INET; 49 } else if (sin->sin_family != AF_INET) { 50 errno = EPFNOSUPPORT; 51 return -1; 52 } 53 54 if (port == 0) { 55 port = START_PORT + (getpid() % NUM_PORTS); 56 } 57 58 for (nn = NUM_PORTS; nn > 0; nn--, port++) 59 { 60 if (port == END_PORT) 61 port = START_PORT; 62 63 sin->sin_port = htons(port); 64 do { 65 ret = bind(sd, (struct sockaddr*)sin, sizeof(*sin)); 66 } while (ret < 0 && errno == EINTR); 67 68 if (!ret) 69 break; 70 } 71 return ret; 72 } 73
