/* $OpenBSD: arc4random_freebsd.h,v 1.3 2015/09/11 11:52:55 deraadt Exp $ */ /* * Copyright (c) 1996, David Mazieres * Copyright (c) 2008, Damien Miller * Copyright (c) 2013, Markus Friedl * Copyright (c) 2014, Theo de Raadt * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ /* * Stub functions for portability. */ #include #include #include static pthread_mutex_t arc4random_mtx = PTHREAD_MUTEX_INITIALIZER; #define _ARC4_LOCK() pthread_mutex_lock(&arc4random_mtx) #define _ARC4_UNLOCK() pthread_mutex_unlock(&arc4random_mtx) /* * Unfortunately, pthread_atfork() is broken on FreeBSD (at least 9 and 10) if * a program does not link to -lthr. Callbacks registered with pthread_atfork() * appear to fail silently. So, it is not always possible to detect a PID * wraparound. */ #define _ARC4_ATFORK(f) pthread_atfork(NULL, NULL, (f)) static inline void _getentropy_fail(void) { raise(SIGKILL); } static volatile sig_atomic_t _rs_forked; static inline void _rs_forkhandler(void) { _rs_forked = 1; } static inline void _rs_forkdetect(void) { static pid_t _rs_pid = 0; pid_t pid = getpid(); if (_rs_pid == 0 || _rs_pid != pid || _rs_forked) { _rs_pid = pid; _rs_forked = 0; if (rs) memset(rs, 0, sizeof(*rs)); } } static inline int _rs_allocate(struct _rs **rsp, struct _rsx **rsxp) { if ((*rsp = mmap(NULL, sizeof(**rsp), PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED) return (-1); if ((*rsxp = mmap(NULL, sizeof(**rsxp), PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED) { munmap(*rsp, sizeof(**rsp)); return (-1); } _ARC4_ATFORK(_rs_forkhandler); return (0); }