/*
* Copyright (c) 2019 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
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*/
#include <sys/sysctl.h>
#include <sys/malloc.h>
#include <pexpert/pexpert.h>
#include <kern/kalloc.h>
#include <kern/percpu.h>
#include <prng/entropy.h>
#include <libkern/section_keywords.h>
SYSCTL_NODE(_kern, OID_AUTO, entropy, CTLFLAG_RD, 0, NULL);
SYSCTL_NODE(_kern_entropy, OID_AUTO, health, CTLFLAG_RD, 0, NULL);
SYSCTL_INT(_kern_entropy_health, OID_AUTO, startup_done, CTLFLAG_RD, &entropy_health_startup_done, 0, NULL);
SYSCTL_NODE(_kern_entropy_health, OID_AUTO, repetition_count_test, CTLFLAG_RD, 0, NULL);
SYSCTL_UINT(_kern_entropy_health_repetition_count_test, OID_AUTO, reset_count, CTLFLAG_RD, &entropy_health_rct_stats.reset_count, 0, NULL);
SYSCTL_UINT(_kern_entropy_health_repetition_count_test, OID_AUTO, failure_count, CTLFLAG_RD, &entropy_health_rct_stats.failure_count, 0, NULL);
SYSCTL_UINT(_kern_entropy_health_repetition_count_test, OID_AUTO, max_observation_count, CTLFLAG_RD, &entropy_health_rct_stats.max_observation_count, 0, NULL);
SYSCTL_NODE(_kern_entropy_health, OID_AUTO, adaptive_proportion_test, CTLFLAG_RD, 0, NULL);
SYSCTL_UINT(_kern_entropy_health_adaptive_proportion_test, OID_AUTO, reset_count, CTLFLAG_RD, &entropy_health_apt_stats.reset_count, 0, NULL);
SYSCTL_UINT(_kern_entropy_health_adaptive_proportion_test, OID_AUTO, failure_count, CTLFLAG_RD, &entropy_health_apt_stats.failure_count, 0, NULL);
SYSCTL_UINT(_kern_entropy_health_adaptive_proportion_test, OID_AUTO, max_observation_count, CTLFLAG_RD, &entropy_health_apt_stats.max_observation_count, 0, NULL);
SYSCTL_NODE(_kern_entropy, OID_AUTO, filter, CTLFLAG_RD, 0,
"Entropy filter information");
SYSCTL_QUAD(_kern_entropy_filter, OID_AUTO, total_sample_count, CTLFLAG_RD, &entropy_filter_total_sample_count,
"The total number of samples processed (i.e. the number of interrupts)");
SYSCTL_QUAD(_kern_entropy_filter, OID_AUTO, accepted_sample_count, CTLFLAG_RD, &entropy_filter_accepted_sample_count,
"The number of samples that passed the filter");
SYSCTL_QUAD(_kern_entropy_filter, OID_AUTO, rejected_sample_count, CTLFLAG_RD, &entropy_filter_rejected_sample_count,
"The number of samples that were rejected by the filters");
SYSCTL_NODE(_kern_entropy, OID_AUTO, analysis, CTLFLAG_RD, 0,
"Subsystem to collect entropy samples for offline analysis");
static int entropy_analysis_supported = ENTROPY_ANALYSIS_SUPPORTED;
SYSCTL_INT(_kern_entropy_analysis, OID_AUTO, supported, CTLFLAG_RD, &entropy_analysis_supported, 0,
"1 if the kernel was built with entropy analysis support; 0 otherwise");
#if ENTROPY_ANALYSIS_SUPPORTED
SYSCTL_INT(_kern_entropy_analysis, OID_AUTO, enabled, CTLFLAG_RD, &entropy_analysis_enabled, 0,
"1 if entropy analysis is enabled (via boot arg); 0 otherwise");
SYSCTL_UINT(_kern_entropy_analysis, OID_AUTO, max_sample_count, CTLFLAG_RD | CTLFLAG_NOAUTO, &entropy_analysis_max_sample_count, 0,
"Target count of samples to be collected");
SYSCTL_UINT(_kern_entropy_analysis, OID_AUTO, sample_count, CTLFLAG_RD | CTLFLAG_NOAUTO, &entropy_analysis_sample_count, 0,
"Current count of samples collected");
static int entropy_analysis_sample_size = sizeof(entropy_sample_t);
SYSCTL_UINT(_kern_entropy_analysis, OID_AUTO, sample_size, CTLFLAG_RD | CTLFLAG_NOAUTO, &entropy_analysis_sample_size, 0,
"Size (in bytes) of a single sample");
SYSCTL_UINT(_kern_entropy_analysis, OID_AUTO, buffer_size, CTLFLAG_RD | CTLFLAG_NOAUTO, &entropy_analysis_buffer_size, 0,
"Size (in bytes) of the buffer of samples");
SYSCTL_UINT(_kern_entropy_analysis, OID_AUTO, filter_size, CTLFLAG_RD | CTLFLAG_NOAUTO, &entropy_analysis_filter_size, 0,
"Size (in bytes) of the filter bitmap");
static int
sysctl_entropy_collect SYSCTL_HANDLER_ARGS
{
if (req->oldptr == USER_ADDR_NULL) {
return SYSCTL_OUT(req, NULL, entropy_analysis_buffer_size);
}
return SYSCTL_OUT(req, entropy_analysis_buffer, entropy_analysis_buffer_size);
}
SYSCTL_PROC(_kern_entropy_analysis, OID_AUTO, buffer,
CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_NOAUTO,
NULL, 0, sysctl_entropy_collect, "-",
"The buffer of samples");
static int
sysctl_entropy_filter SYSCTL_HANDLER_ARGS
{
if (req->oldptr == USER_ADDR_NULL) {
return SYSCTL_OUT(req, NULL, entropy_analysis_filter_size);
}
// There is one bit in the bitmap for each sample.
unsigned filter_nbits = entropy_analysis_max_sample_count;
bitmap_t *filter = bitmap_alloc(filter_nbits);
if (!filter) {
return ENOMEM;
}
entropy_filter(entropy_analysis_max_sample_count, entropy_analysis_buffer, BITMAP_LEN(filter_nbits), filter);
int status = SYSCTL_OUT(req, filter, entropy_analysis_filter_size);
bitmap_free(filter, filter_nbits);
return status;
}
SYSCTL_PROC(_kern_entropy_analysis, OID_AUTO, filter,
CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_NOAUTO,
NULL, 0, sysctl_entropy_filter, "-",
"The bitmap of filtered samples");
__startup_func
static void
entropy_analysis_sysctl_startup(void)
{
uint32_t sample_count = 0;
if (__improbable(PE_parse_boot_argn(ENTROPY_ANALYSIS_BOOTARG, &sample_count, sizeof(sample_count)))) {
sysctl_register_oid_early(&sysctl__kern_entropy_analysis_max_sample_count);
sysctl_register_oid_early(&sysctl__kern_entropy_analysis_sample_count);
sysctl_register_oid_early(&sysctl__kern_entropy_analysis_sample_size);
sysctl_register_oid_early(&sysctl__kern_entropy_analysis_buffer_size);
sysctl_register_oid_early(&sysctl__kern_entropy_analysis_buffer);
sysctl_register_oid_early(&sysctl__kern_entropy_analysis_filter_size);
sysctl_register_oid_early(&sysctl__kern_entropy_analysis_filter);
}
}
STARTUP(SYSCTL, STARTUP_RANK_MIDDLE, entropy_analysis_sysctl_startup);
#endif // ENTROPY_ANALYSIS_SUPPORTED