--- /dev/null
+/*
+ * Copyright 2015-2016 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (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
+ */
+
+/*
+ * Copyright 2004-2014, Akamai Technologies. All Rights Reserved.
+ * This file is distributed under the terms of the OpenSSL license.
+ */
+
+/*
+ * 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 <openssl/crypto.h>
+#include <e_os.h>
+
+#include <string.h>
+
+#if defined(OPENSSL_SYS_LINUX) || defined(OPENSSL_SYS_UNIX)
+# define IMPLEMENTED
+# include <stdlib.h>
+# include <assert.h>
+# include <unistd.h>
+# include <sys/types.h>
+# include <sys/mman.h>
+# include <sys/param.h>
+# include <sys/stat.h>
+# include <fcntl.h>
+#endif
+
+#define CLEAR(p, s) OPENSSL_cleanse(p, s)
+#ifndef PAGE_SIZE
+# define PAGE_SIZE 4096
+#endif
+
+#ifdef IMPLEMENTED
+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, int minsize);
+static char *sh_malloc(size_t size);
+static void sh_free(char *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, int minsize)
+{
+#ifdef IMPLEMENTED
+ int ret = 0;
+
+ if (!secure_mem_initialized) {
+ sec_malloc_lock = CRYPTO_THREAD_lock_new();
+ if (sec_malloc_lock == NULL)
+ return 0;
+ ret = sh_init(size, minsize);
+ secure_mem_initialized = 1;
+ }
+
+ return ret;
+#else
+ return 0;
+#endif /* IMPLEMENTED */
+}
+
+int CRYPTO_secure_malloc_done()
+{
+#ifdef IMPLEMENTED
+ if (secure_mem_used == 0) {
+ sh_done();
+ secure_mem_initialized = 0;
+ CRYPTO_THREAD_lock_free(sec_malloc_lock);
+ return 1;
+ }
+#endif /* IMPLEMENTED */
+ return 0;
+}
+
+int CRYPTO_secure_malloc_initialized()
+{
+#ifdef IMPLEMENTED
+ return secure_mem_initialized;
+#else
+ return 0;
+#endif /* IMPLEMENTED */
+}
+
+void *CRYPTO_secure_malloc(size_t num, const char *file, int line)
+{
+#ifdef IMPLEMENTED
+ 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 /* IMPLEMENTED */
+}
+
+void *CRYPTO_secure_zalloc(size_t num, const char *file, int line)
+{
+ void *ret = CRYPTO_secure_malloc(num, file, line);
+
+ if (ret != NULL)
+ memset(ret, 0, num);
+ return ret;
+}
+
+void CRYPTO_secure_free(void *ptr, const char *file, int line)
+{
+#ifdef IMPLEMENTED
+ 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 /* IMPLEMENTED */
+}
+
+int CRYPTO_secure_allocated(const void *ptr)
+{
+#ifdef IMPLEMENTED
+ 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 /* IMPLEMENTED */
+}
+
+size_t CRYPTO_secure_used()
+{
+#ifdef IMPLEMENTED
+ return secure_mem_used;
+#else
+ return 0;
+#endif /* IMPLEMENTED */
+}
+
+size_t CRYPTO_secure_actual_size(void *ptr)
+{
+#ifdef IMPLEMENTED
+ 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
+}
+/* END OF PAGE ...
+
+ ... START OF PAGE */
+
+/*
+ * SECURE HEAP IMPLEMENTATION
+ */
+#ifdef IMPLEMENTED
+
+
+/*
+ * 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, int minsize)
+{
+ int i, ret;
+ size_t pgsize;
+ size_t aligned;
+
+ memset(&sh, 0, sizeof sh);
+
+ /* make sure size and minsize are powers of 2 */
+ OPENSSL_assert(size > 0);
+ OPENSSL_assert((size & (size - 1)) == 0);
+ OPENSSL_assert(minsize > 0);
+ OPENSSL_assert((minsize & (minsize - 1)) == 0);
+ if (size <= 0 || (size & (size - 1)) != 0)
+ goto err;
+ if (minsize <= 0 || (minsize & (minsize - 1)) != 0)
+ goto err;
+
+ sh.arena_size = size;
+ sh.minsize = minsize;
+ sh.bittable_size = (sh.arena_size / sh.minsize) * 2;
+
+ 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;
+ }
+#else
+ pgsize = PAGE_SIZE;
+#endif
+ sh.map_size = pgsize + sh.arena_size + pgsize;
+ if (1) {
+#ifdef MAP_ANON
+ sh.map_result = mmap(NULL, sh.map_size,
+ PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, -1, 0);
+ } else {
+#endif
+ 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);
+ }
+ }
+ OPENSSL_assert(sh.map_result != MAP_FAILED);
+ if (sh.map_result == MAP_FAILED)
+ goto err;
+ 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;
+
+ /* Starting guard is already aligned from mmap. */
+ if (mprotect(sh.map_result, pgsize, PROT_NONE) < 0)
+ ret = 2;
+
+ /* Ending guard page - need to round up to page boundary */
+ aligned = (pgsize + sh.arena_size + (pgsize - 1)) & ~(pgsize - 1);
+ if (mprotect(sh.map_result + aligned, pgsize, PROT_NONE) < 0)
+ ret = 2;
+
+ if (mlock(sh.arena, sh.arena_size) < 0)
+ ret = 2;
+#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()
+{
+ OPENSSL_free(sh.freelist);
+ OPENSSL_free(sh.bittable);
+ OPENSSL_free(sh.bitmalloc);
+ if (sh.map_result != NULL && sh.map_size)
+ munmap(sh.map_result, sh.map_size);
+ 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 char *sh_malloc(size_t size)
+{
+ ossl_ssize_t list, slist;
+ size_t i;
+ char *chunk;
+
+ 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));
+
+ return chunk;
+}
+
+static void sh_free(char *ptr)
+{
+ size_t list;
+ char *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--;
+
+ 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 /* IMPLEMENTED */
projects / cassiopeia.git / blobdiff