A local copy of OpenSSL from GitHub
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/*
* Copyright 2015-2020 The OpenSSL Project Authors. All Rights Reserved.
* Copyright 2004-2014, Akamai Technologies. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
/*
* This file is in two halves. The first half implements the public API
* to be used by external consumers, and to be used by OpenSSL to store
* data in a "secure arena." The second half implements the secure arena.
* For details on that implementation, see below (look for uppercase
* "SECURE HEAP IMPLEMENTATION").
*/
#include "e_os.h"
#include <openssl/crypto.h>
#include <string.h>
#ifndef OPENSSL_NO_SECURE_MEMORY
# if defined(_WIN32)
# include <windows.h>
# endif
# include <stdlib.h>
# include <assert.h>
# if defined(OPENSSL_SYS_UNIX)
# include <unistd.h>
# endif
# include <sys/types.h>
# if defined(OPENSSL_SYS_UNIX)
# include <sys/mman.h>
# if defined(__FreeBSD__)
# define MADV_DONTDUMP MADV_NOCORE
# endif
# if !defined(MAP_CONCEAL)
# define MAP_CONCEAL 0
# endif
# endif
# if defined(OPENSSL_SYS_LINUX)
# include <sys/syscall.h>
# if defined(SYS_mlock2)
# include <linux/mman.h>
# include <errno.h>
# endif
# include <sys/param.h>
# endif
# include <sys/stat.h>
# include <fcntl.h>
#endif
#define CLEAR(p, s) OPENSSL_cleanse(p, s)
#ifndef PAGE_SIZE
# define PAGE_SIZE 4096
#endif
#if !defined(MAP_ANON) && defined(MAP_ANONYMOUS)
# define MAP_ANON MAP_ANONYMOUS
#endif
#ifndef OPENSSL_NO_SECURE_MEMORY
static size_t secure_mem_used;
static int secure_mem_initialized;
static CRYPTO_RWLOCK *sec_malloc_lock = NULL;
/*
* These are the functions that must be implemented by a secure heap (sh).
*/
static int sh_init(size_t size, size_t minsize);
static void *sh_malloc(size_t size);
static void sh_free(void *ptr);
static void sh_done(void);
static size_t sh_actual_size(char *ptr);
static int sh_allocated(const char *ptr);
#endif
int CRYPTO_secure_malloc_init(size_t size, size_t minsize)
{
#ifndef OPENSSL_NO_SECURE_MEMORY
int ret = 0;
if (!secure_mem_initialized) {
sec_malloc_lock = CRYPTO_THREAD_lock_new();
if (sec_malloc_lock == NULL)
return 0;
if ((ret = sh_init(size, minsize)) != 0) {
secure_mem_initialized = 1;
} else {
CRYPTO_THREAD_lock_free(sec_malloc_lock);
sec_malloc_lock = NULL;
}
}
return ret;
#else
return 0;
#endif /* OPENSSL_NO_SECURE_MEMORY */
}
int CRYPTO_secure_malloc_done(void)
{
#ifndef OPENSSL_NO_SECURE_MEMORY
if (secure_mem_used == 0) {
sh_done();
secure_mem_initialized = 0;
CRYPTO_THREAD_lock_free(sec_malloc_lock);
sec_malloc_lock = NULL;
return 1;
}
#endif /* OPENSSL_NO_SECURE_MEMORY */
return 0;
}
int CRYPTO_secure_malloc_initialized(void)
{
#ifndef OPENSSL_NO_SECURE_MEMORY
return secure_mem_initialized;
#else
return 0;
#endif /* OPENSSL_NO_SECURE_MEMORY */
}
void *CRYPTO_secure_malloc(size_t num, const char *file, int line)
{
#ifndef OPENSSL_NO_SECURE_MEMORY
void *ret;
size_t actual_size;
if (!secure_mem_initialized) {
return CRYPTO_malloc(num, file, line);
}
CRYPTO_THREAD_write_lock(sec_malloc_lock);
ret = sh_malloc(num);
actual_size = ret ? sh_actual_size(ret) : 0;
secure_mem_used += actual_size;
CRYPTO_THREAD_unlock(sec_malloc_lock);
return ret;
#else
return CRYPTO_malloc(num, file, line);
#endif /* OPENSSL_NO_SECURE_MEMORY */
}
void *CRYPTO_secure_zalloc(size_t num, const char *file, int line)
{
#ifndef OPENSSL_NO_SECURE_MEMORY
if (secure_mem_initialized)
/* CRYPTO_secure_malloc() zeroes allocations when it is implemented */
return CRYPTO_secure_malloc(num, file, line);
#endif
return CRYPTO_zalloc(num, file, line);
}
void CRYPTO_secure_free(void *ptr, const char *file, int line)
{
#ifndef OPENSSL_NO_SECURE_MEMORY
size_t actual_size;
if (ptr == NULL)
return;
if (!CRYPTO_secure_allocated(ptr)) {
CRYPTO_free(ptr, file, line);
return;
}
CRYPTO_THREAD_write_lock(sec_malloc_lock);
actual_size = sh_actual_size(ptr);
CLEAR(ptr, actual_size);
secure_mem_used -= actual_size;
sh_free(ptr);
CRYPTO_THREAD_unlock(sec_malloc_lock);
#else
CRYPTO_free(ptr, file, line);
#endif /* OPENSSL_NO_SECURE_MEMORY */
}
void CRYPTO_secure_clear_free(void *ptr, size_t num,
const char *file, int line)
{
#ifndef OPENSSL_NO_SECURE_MEMORY
size_t actual_size;
if (ptr == NULL)
return;
if (!CRYPTO_secure_allocated(ptr)) {
OPENSSL_cleanse(ptr, num);
CRYPTO_free(ptr, file, line);
return;
}
CRYPTO_THREAD_write_lock(sec_malloc_lock);
actual_size = sh_actual_size(ptr);
CLEAR(ptr, actual_size);
secure_mem_used -= actual_size;
sh_free(ptr);
CRYPTO_THREAD_unlock(sec_malloc_lock);
#else
if (ptr == NULL)
return;
OPENSSL_cleanse(ptr, num);
CRYPTO_free(ptr, file, line);
#endif /* OPENSSL_NO_SECURE_MEMORY */
}
int CRYPTO_secure_allocated(const void *ptr)
{
#ifndef OPENSSL_NO_SECURE_MEMORY
int ret;
if (!secure_mem_initialized)
return 0;
CRYPTO_THREAD_write_lock(sec_malloc_lock);
ret = sh_allocated(ptr);
CRYPTO_THREAD_unlock(sec_malloc_lock);
return ret;
#else
return 0;
#endif /* OPENSSL_NO_SECURE_MEMORY */
}
size_t CRYPTO_secure_used(void)
{
#ifndef OPENSSL_NO_SECURE_MEMORY
return secure_mem_used;
#else
return 0;
#endif /* OPENSSL_NO_SECURE_MEMORY */
}
size_t CRYPTO_secure_actual_size(void *ptr)
{
#ifndef OPENSSL_NO_SECURE_MEMORY
size_t actual_size;
CRYPTO_THREAD_write_lock(sec_malloc_lock);
actual_size = sh_actual_size(ptr);
CRYPTO_THREAD_unlock(sec_malloc_lock);
return actual_size;
#else
return 0;
#endif
}
/*
* SECURE HEAP IMPLEMENTATION
*/
#ifndef OPENSSL_NO_SECURE_MEMORY
/*
* The implementation provided here uses a fixed-sized mmap() heap,
* which is locked into memory, not written to core files, and protected
* on either side by an unmapped page, which will catch pointer overruns
* (or underruns) and an attempt to read data out of the secure heap.
* Free'd memory is zero'd or otherwise cleansed.
*
* This is a pretty standard buddy allocator. We keep areas in a multiple
* of "sh.minsize" units. The freelist and bitmaps are kept separately,
* so all (and only) data is kept in the mmap'd heap.
*
* This code assumes eight-bit bytes. The numbers 3 and 7 are all over the
* place.
*/
#define ONE ((size_t)1)
# define TESTBIT(t, b) (t[(b) >> 3] & (ONE << ((b) & 7)))
# define SETBIT(t, b) (t[(b) >> 3] |= (ONE << ((b) & 7)))
# define CLEARBIT(t, b) (t[(b) >> 3] &= (0xFF & ~(ONE << ((b) & 7))))
#define WITHIN_ARENA(p) \
((char*)(p) >= sh.arena && (char*)(p) < &sh.arena[sh.arena_size])
#define WITHIN_FREELIST(p) \
((char*)(p) >= (char*)sh.freelist && (char*)(p) < (char*)&sh.freelist[sh.freelist_size])
typedef struct sh_list_st
{
struct sh_list_st *next;
struct sh_list_st **p_next;
} SH_LIST;
typedef struct sh_st
{
char* map_result;
size_t map_size;
char *arena;
size_t arena_size;
char **freelist;
ossl_ssize_t freelist_size;
size_t minsize;
unsigned char *bittable;
unsigned char *bitmalloc;
size_t bittable_size; /* size in bits */
} SH;
static SH sh;
static size_t sh_getlist(char *ptr)
{
ossl_ssize_t list = sh.freelist_size - 1;
size_t bit = (sh.arena_size + ptr - sh.arena) / sh.minsize;
for (; bit; bit >>= 1, list--) {
if (TESTBIT(sh.bittable, bit))
break;
OPENSSL_assert((bit & 1) == 0);
}
return list;
}
static int sh_testbit(char *ptr, int list, unsigned char *table)
{
size_t bit;
OPENSSL_assert(list >= 0 && list < sh.freelist_size);
OPENSSL_assert(((ptr - sh.arena) & ((sh.arena_size >> list) - 1)) == 0);
bit = (ONE << list) + ((ptr - sh.arena) / (sh.arena_size >> list));
OPENSSL_assert(bit > 0 && bit < sh.bittable_size);
return TESTBIT(table, bit);
}
static void sh_clearbit(char *ptr, int list, unsigned char *table)
{
size_t bit;
OPENSSL_assert(list >= 0 && list < sh.freelist_size);
OPENSSL_assert(((ptr - sh.arena) & ((sh.arena_size >> list) - 1)) == 0);
bit = (ONE << list) + ((ptr - sh.arena) / (sh.arena_size >> list));
OPENSSL_assert(bit > 0 && bit < sh.bittable_size);
OPENSSL_assert(TESTBIT(table, bit));
CLEARBIT(table, bit);
}
static void sh_setbit(char *ptr, int list, unsigned char *table)
{
size_t bit;
OPENSSL_assert(list >= 0 && list < sh.freelist_size);
OPENSSL_assert(((ptr - sh.arena) & ((sh.arena_size >> list) - 1)) == 0);
bit = (ONE << list) + ((ptr - sh.arena) / (sh.arena_size >> list));
OPENSSL_assert(bit > 0 && bit < sh.bittable_size);
OPENSSL_assert(!TESTBIT(table, bit));
SETBIT(table, bit);
}
static void sh_add_to_list(char **list, char *ptr)
{
SH_LIST *temp;
OPENSSL_assert(WITHIN_FREELIST(list));
OPENSSL_assert(WITHIN_ARENA(ptr));
temp = (SH_LIST *)ptr;
temp->next = *(SH_LIST **)list;
OPENSSL_assert(temp->next == NULL || WITHIN_ARENA(temp->next));
temp->p_next = (SH_LIST **)list;
if (temp->next != NULL) {
OPENSSL_assert((char **)temp->next->p_next == list);
temp->next->p_next = &(temp->next);
}
*list = ptr;
}
static void sh_remove_from_list(char *ptr)
{
SH_LIST *temp, *temp2;
temp = (SH_LIST *)ptr;
if (temp->next != NULL)
temp->next->p_next = temp->p_next;
*temp->p_next = temp->next;
if (temp->next == NULL)
return;
temp2 = temp->next;
OPENSSL_assert(WITHIN_FREELIST(temp2->p_next) || WITHIN_ARENA(temp2->p_next));
}
static int sh_init(size_t size, size_t minsize)
{
int ret;
size_t i;
size_t pgsize;
size_t aligned;
#if defined(_WIN32)
DWORD flOldProtect;
SYSTEM_INFO systemInfo;
#endif
memset(&sh, 0, sizeof(sh));
/* make sure size is a powers of 2 */
OPENSSL_assert(size > 0);
OPENSSL_assert((size & (size - 1)) == 0);
if (size == 0 || (size & (size - 1)) != 0)
goto err;
if (minsize <= sizeof(SH_LIST)) {
OPENSSL_assert(sizeof(SH_LIST) <= 65536);
/*
* Compute the minimum possible allocation size.
* This must be a power of 2 and at least as large as the SH_LIST
* structure.
*/
minsize = sizeof(SH_LIST) - 1;
minsize |= minsize >> 1;
minsize |= minsize >> 2;
if (sizeof(SH_LIST) > 16)
minsize |= minsize >> 4;
if (sizeof(SH_LIST) > 256)
minsize |= minsize >> 8;
minsize++;
} else {
/* make sure minsize is a powers of 2 */
OPENSSL_assert((minsize & (minsize - 1)) == 0);
if ((minsize & (minsize - 1)) != 0)
goto err;
}
sh.arena_size = size;
sh.minsize = minsize;
sh.bittable_size = (sh.arena_size / sh.minsize) * 2;
/* Prevent allocations of size 0 later on */
if (sh.bittable_size >> 3 == 0)
goto err;
sh.freelist_size = -1;
for (i = sh.bittable_size; i; i >>= 1)
sh.freelist_size++;
sh.freelist = OPENSSL_zalloc(sh.freelist_size * sizeof(char *));
OPENSSL_assert(sh.freelist != NULL);
if (sh.freelist == NULL)
goto err;
sh.bittable = OPENSSL_zalloc(sh.bittable_size >> 3);
OPENSSL_assert(sh.bittable != NULL);
if (sh.bittable == NULL)
goto err;
sh.bitmalloc = OPENSSL_zalloc(sh.bittable_size >> 3);
OPENSSL_assert(sh.bitmalloc != NULL);
if (sh.bitmalloc == NULL)
goto err;
/* Allocate space for heap, and two extra pages as guards */
#if defined(_SC_PAGE_SIZE) || defined (_SC_PAGESIZE)
{
# if defined(_SC_PAGE_SIZE)
long tmppgsize = sysconf(_SC_PAGE_SIZE);
# else
long tmppgsize = sysconf(_SC_PAGESIZE);
# endif
if (tmppgsize < 1)
pgsize = PAGE_SIZE;
else
pgsize = (size_t)tmppgsize;
}
#elif defined(_WIN32)
GetSystemInfo(&systemInfo);
pgsize = (size_t)systemInfo.dwPageSize;
#else
pgsize = PAGE_SIZE;
#endif
sh.map_size = pgsize + sh.arena_size + pgsize;
#if !defined(_WIN32)
# ifdef MAP_ANON
sh.map_result = mmap(NULL, sh.map_size,
PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE|MAP_CONCEAL, -1, 0);
# else
{
int fd;
sh.map_result = MAP_FAILED;
if ((fd = open("/dev/zero", O_RDWR)) >= 0) {
sh.map_result = mmap(NULL, sh.map_size,
PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
close(fd);
}
}
# endif
if (sh.map_result == MAP_FAILED)
goto err;
#else
sh.map_result = VirtualAlloc(NULL, sh.map_size, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
if (sh.map_result == NULL)
goto err;
#endif
sh.arena = (char *)(sh.map_result + pgsize);
sh_setbit(sh.arena, 0, sh.bittable);
sh_add_to_list(&sh.freelist[0], sh.arena);
/* Now try to add guard pages and lock into memory. */
ret = 1;
#if !defined(_WIN32)
/* Starting guard is already aligned from mmap. */
if (mprotect(sh.map_result, pgsize, PROT_NONE) < 0)
ret = 2;
#else
if (VirtualProtect(sh.map_result, pgsize, PAGE_NOACCESS, &flOldProtect) == FALSE)
ret = 2;
#endif
/* Ending guard page - need to round up to page boundary */
aligned = (pgsize + sh.arena_size + (pgsize - 1)) & ~(pgsize - 1);
#if !defined(_WIN32)
if (mprotect(sh.map_result + aligned, pgsize, PROT_NONE) < 0)
ret = 2;
#else
if (VirtualProtect(sh.map_result + aligned, pgsize, PAGE_NOACCESS, &flOldProtect) == FALSE)
ret = 2;
#endif
#if defined(OPENSSL_SYS_LINUX) && defined(MLOCK_ONFAULT) && defined(SYS_mlock2)
if (syscall(SYS_mlock2, sh.arena, sh.arena_size, MLOCK_ONFAULT) < 0) {
if (errno == ENOSYS) {
if (mlock(sh.arena, sh.arena_size) < 0)
ret = 2;
} else {
ret = 2;
}
}
#elif defined(_WIN32)
if (VirtualLock(sh.arena, sh.arena_size) == FALSE)
ret = 2;
#else
if (mlock(sh.arena, sh.arena_size) < 0)
ret = 2;
#endif
#ifdef MADV_DONTDUMP
if (madvise(sh.arena, sh.arena_size, MADV_DONTDUMP) < 0)
ret = 2;
#endif
return ret;
err:
sh_done();
return 0;
}
static void sh_done(void)
{
OPENSSL_free(sh.freelist);
OPENSSL_free(sh.bittable);
OPENSSL_free(sh.bitmalloc);
#if !defined(_WIN32)
if (sh.map_result != MAP_FAILED && sh.map_size)
munmap(sh.map_result, sh.map_size);
#else
if (sh.map_result != NULL && sh.map_size)
VirtualFree(sh.map_result, 0, MEM_RELEASE);
#endif
memset(&sh, 0, sizeof(sh));
}
static int sh_allocated(const char *ptr)
{
return WITHIN_ARENA(ptr) ? 1 : 0;
}
static char *sh_find_my_buddy(char *ptr, int list)
{
size_t bit;
char *chunk = NULL;
bit = (ONE << list) + (ptr - sh.arena) / (sh.arena_size >> list);
bit ^= 1;
if (TESTBIT(sh.bittable, bit) && !TESTBIT(sh.bitmalloc, bit))
chunk = sh.arena + ((bit & ((ONE << list) - 1)) * (sh.arena_size >> list));
return chunk;
}
static void *sh_malloc(size_t size)
{
ossl_ssize_t list, slist;
size_t i;
char *chunk;
if (size > sh.arena_size)
return NULL;
list = sh.freelist_size - 1;
for (i = sh.minsize; i < size; i <<= 1)
list--;
if (list < 0)
return NULL;
/* try to find a larger entry to split */
for (slist = list; slist >= 0; slist--)
if (sh.freelist[slist] != NULL)
break;
if (slist < 0)
return NULL;
/* split larger entry */
while (slist != list) {
char *temp = sh.freelist[slist];
/* remove from bigger list */
OPENSSL_assert(!sh_testbit(temp, slist, sh.bitmalloc));
sh_clearbit(temp, slist, sh.bittable);
sh_remove_from_list(temp);
OPENSSL_assert(temp != sh.freelist[slist]);
/* done with bigger list */
slist++;
/* add to smaller list */
OPENSSL_assert(!sh_testbit(temp, slist, sh.bitmalloc));
sh_setbit(temp, slist, sh.bittable);
sh_add_to_list(&sh.freelist[slist], temp);
OPENSSL_assert(sh.freelist[slist] == temp);
/* split in 2 */
temp += sh.arena_size >> slist;
OPENSSL_assert(!sh_testbit(temp, slist, sh.bitmalloc));
sh_setbit(temp, slist, sh.bittable);
sh_add_to_list(&sh.freelist[slist], temp);
OPENSSL_assert(sh.freelist[slist] == temp);
OPENSSL_assert(temp-(sh.arena_size >> slist) == sh_find_my_buddy(temp, slist));
}
/* peel off memory to hand back */
chunk = sh.freelist[list];
OPENSSL_assert(sh_testbit(chunk, list, sh.bittable));
sh_setbit(chunk, list, sh.bitmalloc);
sh_remove_from_list(chunk);
OPENSSL_assert(WITHIN_ARENA(chunk));
/* zero the free list header as a precaution against information leakage */
memset(chunk, 0, sizeof(SH_LIST));
return chunk;
}
static void sh_free(void *ptr)
{
size_t list;
void *buddy;
if (ptr == NULL)
return;
OPENSSL_assert(WITHIN_ARENA(ptr));
if (!WITHIN_ARENA(ptr))
return;
list = sh_getlist(ptr);
OPENSSL_assert(sh_testbit(ptr, list, sh.bittable));
sh_clearbit(ptr, list, sh.bitmalloc);
sh_add_to_list(&sh.freelist[list], ptr);
/* Try to coalesce two adjacent free areas. */
while ((buddy = sh_find_my_buddy(ptr, list)) != NULL) {
OPENSSL_assert(ptr == sh_find_my_buddy(buddy, list));
OPENSSL_assert(ptr != NULL);
OPENSSL_assert(!sh_testbit(ptr, list, sh.bitmalloc));
sh_clearbit(ptr, list, sh.bittable);
sh_remove_from_list(ptr);
OPENSSL_assert(!sh_testbit(ptr, list, sh.bitmalloc));
sh_clearbit(buddy, list, sh.bittable);
sh_remove_from_list(buddy);
list--;
/* Zero the higher addressed block's free list pointers */
memset(ptr > buddy ? ptr : buddy, 0, sizeof(SH_LIST));
if (ptr > buddy)
ptr = buddy;
OPENSSL_assert(!sh_testbit(ptr, list, sh.bitmalloc));
sh_setbit(ptr, list, sh.bittable);
sh_add_to_list(&sh.freelist[list], ptr);
OPENSSL_assert(sh.freelist[list] == ptr);
}
}
static size_t sh_actual_size(char *ptr)
{
int list;
OPENSSL_assert(WITHIN_ARENA(ptr));
if (!WITHIN_ARENA(ptr))
return 0;
list = sh_getlist(ptr);
OPENSSL_assert(sh_testbit(ptr, list, sh.bittable));
return sh.arena_size / (ONE << list);
}
#endif /* OPENSSL_NO_SECURE_MEMORY */