| /* |
| * Copyright (c) 2010, Oracle America, Inc. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following |
| * disclaimer in the documentation and/or other materials |
| * provided with the distribution. |
| * * Neither the name of the "Oracle America, Inc." nor the names of its |
| * contributors may be used to endorse or promote products derived |
| * from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, |
| * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE |
| * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
| * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
| * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include <errno.h> |
| #include <unistd.h> |
| #include <string.h> |
| #include <sys/types.h> |
| #include <sys/socket.h> |
| #include <netinet/in.h> |
| #include <bits/libc-lock.h> |
| |
| /* |
| * Locks the static variables in this file. |
| */ |
| __libc_lock_define_initialized (static, lock); |
| |
| /* |
| * Bind a socket to a privileged IP port |
| */ |
| int |
| bindresvport (int sd, struct sockaddr_in *sin) |
| { |
| static short port; |
| struct sockaddr_in myaddr; |
| int i; |
| |
| #define STARTPORT 600 |
| #define LOWPORT 512 |
| #define ENDPORT (IPPORT_RESERVED - 1) |
| #define NPORTS (ENDPORT - STARTPORT + 1) |
| static short startport = STARTPORT; |
| |
| if (sin == (struct sockaddr_in *) 0) |
| { |
| sin = &myaddr; |
| __bzero (sin, sizeof (*sin)); |
| sin->sin_family = AF_INET; |
| } |
| else if (sin->sin_family != AF_INET) |
| { |
| __set_errno (EAFNOSUPPORT); |
| return -1; |
| } |
| |
| if (port == 0) |
| { |
| port = (__getpid () % NPORTS) + STARTPORT; |
| } |
| |
| /* Initialize to make gcc happy. */ |
| int res = -1; |
| |
| int nports = ENDPORT - startport + 1; |
| int endport = ENDPORT; |
| |
| __libc_lock_lock (lock); |
| |
| again: |
| for (i = 0; i < nports; ++i) |
| { |
| sin->sin_port = htons (port++); |
| if (port > endport) |
| port = startport; |
| res = __bind (sd, sin, sizeof (struct sockaddr_in)); |
| if (res >= 0 || errno != EADDRINUSE) |
| break; |
| } |
| |
| if (i == nports && startport != LOWPORT) |
| { |
| startport = LOWPORT; |
| endport = STARTPORT - 1; |
| nports = STARTPORT - LOWPORT; |
| port = LOWPORT + port % (STARTPORT - LOWPORT); |
| goto again; |
| } |
| |
| __libc_lock_unlock (lock); |
| |
| return res; |
| } |
| libc_hidden_def (bindresvport) |
