| xf.li | bdd93d5 | 2023-05-12 07:10:14 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (c) 2010, Oracle America, Inc. |
| 3 | * |
| 4 | * Redistribution and use in source and binary forms, with or without |
| 5 | * modification, are permitted provided that the following conditions are |
| 6 | * met: |
| 7 | * |
| 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 |
| 11 | * copyright notice, this list of conditions and the following |
| 12 | * disclaimer in the documentation and/or other materials |
| 13 | * provided with the distribution. |
| 14 | * * Neither the name of the "Oracle America, Inc." nor the names of its |
| 15 | * contributors may be used to endorse or promote products derived |
| 16 | * from this software without specific prior written permission. |
| 17 | * |
| 18 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 19 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 20 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| 21 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| 22 | * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, |
| 23 | * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 24 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE |
| 25 | * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 26 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
| 27 | * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
| 28 | * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| 29 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 30 | */ |
| 31 | |
| 32 | #include <errno.h> |
| 33 | #include <unistd.h> |
| 34 | #include <string.h> |
| 35 | #include <sys/types.h> |
| 36 | #include <sys/socket.h> |
| 37 | #include <netinet/in.h> |
| 38 | #include <libc-lock.h> |
| 39 | |
| 40 | /* |
| 41 | * Locks the static variables in this file. |
| 42 | */ |
| 43 | __libc_lock_define_initialized (static, lock); |
| 44 | |
| 45 | /* |
| 46 | * Bind a socket to a privileged IP port |
| 47 | */ |
| 48 | int |
| 49 | bindresvport (int sd, struct sockaddr_in *sin) |
| 50 | { |
| 51 | static short port; |
| 52 | struct sockaddr_in myaddr; |
| 53 | int i; |
| 54 | |
| 55 | #define STARTPORT 600 |
| 56 | #define LOWPORT 512 |
| 57 | #define ENDPORT (IPPORT_RESERVED - 1) |
| 58 | #define NPORTS (ENDPORT - STARTPORT + 1) |
| 59 | static short startport = STARTPORT; |
| 60 | |
| 61 | if (sin == (struct sockaddr_in *) 0) |
| 62 | { |
| 63 | sin = &myaddr; |
| 64 | __bzero (sin, sizeof (*sin)); |
| 65 | sin->sin_family = AF_INET; |
| 66 | } |
| 67 | else if (sin->sin_family != AF_INET) |
| 68 | { |
| 69 | __set_errno (EAFNOSUPPORT); |
| 70 | return -1; |
| 71 | } |
| 72 | |
| 73 | if (port == 0) |
| 74 | { |
| 75 | port = (__getpid () % NPORTS) + STARTPORT; |
| 76 | } |
| 77 | |
| 78 | /* Initialize to make gcc happy. */ |
| 79 | int res = -1; |
| 80 | |
| 81 | int nports = ENDPORT - startport + 1; |
| 82 | int endport = ENDPORT; |
| 83 | |
| 84 | __libc_lock_lock (lock); |
| 85 | |
| 86 | again: |
| 87 | for (i = 0; i < nports; ++i) |
| 88 | { |
| 89 | sin->sin_port = htons (port++); |
| 90 | if (port > endport) |
| 91 | port = startport; |
| 92 | res = __bind (sd, sin, sizeof (struct sockaddr_in)); |
| 93 | if (res >= 0 || errno != EADDRINUSE) |
| 94 | break; |
| 95 | } |
| 96 | |
| 97 | if (i == nports && startport != LOWPORT) |
| 98 | { |
| 99 | startport = LOWPORT; |
| 100 | endport = STARTPORT - 1; |
| 101 | nports = STARTPORT - LOWPORT; |
| 102 | port = LOWPORT + port % (STARTPORT - LOWPORT); |
| 103 | goto again; |
| 104 | } |
| 105 | |
| 106 | __libc_lock_unlock (lock); |
| 107 | |
| 108 | return res; |
| 109 | } |
| 110 | libc_hidden_def (bindresvport) |