4312ebfe0b
r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are still not MPSAFE (or already are but aren’t properly marked). Use it in preparation for a general review of all nodes. This is non-functional change that adds annotations to SYSCTL_NODE and SYSCTL_PROC nodes using one of the soon-to-be-required flags. Mark all obvious cases as MPSAFE. All entries that haven't been marked as MPSAFE before are by default marked as NEEDGIANT Reviewed by: cem Approved by: csprng, kib (mentor, blanket) Differential Revision: https://reviews.freebsd.org/D23841
106 lines
4.5 KiB
C
106 lines
4.5 KiB
C
/*-
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* Copyright (c) 2015 Mark R V Murray
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer
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* in this position and unchanged.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/kernel.h>
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#include <sys/malloc.h>
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#include <sys/random.h>
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#include <sys/sysctl.h>
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#include <dev/random/randomdev.h>
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/* Set up the sysctl root node for the entropy device */
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SYSCTL_NODE(_kern, OID_AUTO, random, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
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"Cryptographically Secure Random Number Generator");
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SYSCTL_NODE(_kern_random, OID_AUTO, initial_seeding,
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CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
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"Initial seeding control and information");
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/*
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* N.B., this is a dangerous default, but it matches the behavior prior to
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* r346250 (and, say, OpenBSD -- although they get some guaranteed saved
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* entropy from the prior boot because of their KARL system, on RW media).
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*/
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bool random_bypass_before_seeding = true;
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SYSCTL_BOOL(_kern_random_initial_seeding, OID_AUTO,
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bypass_before_seeding, CTLFLAG_RDTUN, &random_bypass_before_seeding,
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0, "If set non-zero, bypass the random device in requests for random "
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"data when the random device is not yet seeded. This is considered "
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"dangerous. Ordinarily, the random device will block requests until "
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"it is seeded by sufficient entropy.");
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/*
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* This is a read-only diagnostic that reports the combination of the former
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* tunable and actual bypass. It is intended for programmatic inspection by
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* userspace administrative utilities after boot.
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*/
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bool read_random_bypassed_before_seeding = false;
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SYSCTL_BOOL(_kern_random_initial_seeding, OID_AUTO,
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read_random_bypassed_before_seeding, CTLFLAG_RD,
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&read_random_bypassed_before_seeding, 0, "If non-zero, the random device "
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"was bypassed because the 'bypass_before_seeding' knob was enabled and a "
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"request was submitted prior to initial seeding.");
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/*
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* This is a read-only diagnostic that reports the combination of the former
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* tunable and actual bypass for arc4random initial seeding. It is intended
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* for programmatic inspection by userspace administrative utilities after
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* boot.
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*/
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bool arc4random_bypassed_before_seeding = false;
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SYSCTL_BOOL(_kern_random_initial_seeding, OID_AUTO,
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arc4random_bypassed_before_seeding, CTLFLAG_RD,
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&arc4random_bypassed_before_seeding, 0, "If non-zero, the random device "
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"was bypassed when initially seeding the kernel arc4random(9), because "
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"the 'bypass_before_seeding' knob was enabled and a request was submitted "
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"prior to initial seeding.");
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/*
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* This knob is for users who do not want additional warnings in their logs
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* because they intend to handle bypass by inspecting the status of the
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* diagnostic sysctls.
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*/
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bool random_bypass_disable_warnings = false;
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SYSCTL_BOOL(_kern_random_initial_seeding, OID_AUTO,
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disable_bypass_warnings, CTLFLAG_RDTUN,
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&random_bypass_disable_warnings, 0, "If non-zero, do not log a warning "
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"if the 'bypass_before_seeding' knob is enabled and a request is "
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"submitted prior to initial seeding.");
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MALLOC_DEFINE(M_ENTROPY, "entropy", "Entropy harvesting buffers and data structures");
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#if defined(RANDOM_LOADABLE)
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const struct random_algorithm *p_random_alg_context;
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void (*_read_random)(void *, u_int);
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int (*_read_random_uio)(struct uio *, bool);
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bool (*_is_random_seeded)(void);
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#endif /* defined(RANDOM_LOADABLE) */
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