gnome-keyring r1562 - in trunk: . egg
- From: nnielsen svn gnome org
- To: svn-commits-list gnome org
- Subject: gnome-keyring r1562 - in trunk: . egg
- Date: Fri, 13 Feb 2009 04:21:00 +0000 (UTC)
Author: nnielsen
Date: Fri Feb 13 04:21:00 2009
New Revision: 1562
URL: http://svn.gnome.org/viewvc/gnome-keyring?rev=1562&view=rev
Log:
Completely overhaul the secure memory allocator.
Don't store metadata inside the secure memory area. Add memory guards, so that we can see if/when memory is incorrectly overflown.
Modified:
trunk/ChangeLog
trunk/egg/egg-secure-memory.c
Modified: trunk/egg/egg-secure-memory.c
==============================================================================
--- trunk/egg/egg-secure-memory.c (original)
+++ trunk/egg/egg-secure-memory.c Fri Feb 13 04:21:00 2009
@@ -72,318 +72,552 @@
#define DO_UNLOCK() \
egg_memory_unlock ();
-#define MEM_ALIGN (sizeof(void*) > sizeof(long) ? sizeof(void*) : sizeof(long))
+static int lock_warning = 1;
-/* -----------------------------------------------------------------------------
- * BLOCK SUBALLOCATION
+
+/*
+ * We allocate all memory in units of sizeof(void*). This
+ * is our definition of 'word'.
*/
+typedef void* word_t;
-/* suba - sub-allocate memory from larger chunk of memory
- * Copyright (c) 2003 Michael B. Allen <mba2000 ioplex.com>
- *
- * The MIT License
- *
- * Permission is hereby granted, free of charge, to any person obtaining a
- * copy of this software and associated documentation files (the "Software"),
- * to deal in the Software without restriction, including without limitation
- * the rights to use, copy, modify, merge, publish, distribute, sublicense,
- * and/or sell copies of the Software, and to permit persons to whom the
- * Software is furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included
- * in all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
- * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
- * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
- * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
- * OTHER DEALINGS IN THE SOFTWARE.
+/* The amount of extra words we can allocate */
+#define WASTE 4
+
+/*
+ * Track allocated memory or a free block. This structure is not stored
+ * in the secure memory area. It is allocated from a pool of other
+ * memory. See meta_pool_xxx ().
*/
+typedef struct _Cell {
+ word_t *words; /* Pointer to secure memory */
+ size_t n_words; /* Amount of secure memory in words */
+ size_t allocated; /* Amount actually requested by app, in bytes, 0 if unused */
+ struct _Cell *next; /* Next in unused memory ring, or NULL if used */
+ struct _Cell *prev; /* Previous in unused memory ring, or NULL if used */
+} Cell;
-typedef size_t ref_t; /* suba offset from start of memory to object */
+/*
+ * A block of secure memory. This structure is the header in that block.
+ */
+typedef struct _Block {
+ word_t *words; /* Actual memory hangs off here */
+ size_t n_words; /* Number of words in block */
+ size_t used; /* Number of used allocations */
+ struct _Cell* unused; /* Ring of unused allocations */
+ struct _Block *next; /* Next block in list */
+} Block;
-#define SUBA_MAGIC "\xFF\x15\x15\x15SUBA"
-#define CELL_MAGIC 0x7777CE11
-#define ALIGN(s) ((((s) / MEM_ALIGN) + (((s) % MEM_ALIGN) ? 1 : 0)) * MEM_ALIGN)
-#define POFF (ALIGN(sizeof(size_t)) + ALIGN(sizeof(unsigned int)))
-#define C2P(c) ((char *)(c) + POFF)
-#define P2C(p) ((struct cell *)((char *)(p) - POFF))
-#define ISADJ(c1,c2) ((struct cell *)(C2P(c1) + (c1)->size) == (struct cell *)(c2))
-#define MINCELL 32
-#define HDRSIZ (ALIGN (sizeof *suba))
-
-struct allocator {
- unsigned char magic[8]; /* suba header identifier */
- ref_t tail; /* offset to first cell in free list */
- size_t size; /* total size of memory area */
- size_t alloc_total; /* total bytes utilized from this allocator */
- size_t free_total; /* total bytes released from this allocator */
- size_t size_total; /* total bytes requested from this allocator */
-};
-
-struct cell {
- size_t size;
- unsigned int magic;
- ref_t next; /* reference to next cell in free list */
-};
+/* -----------------------------------------------------------------------------
+ * UNUSED STACK
+ */
+
+static inline void
+unused_push (void **stack, void *ptr)
+{
+ ASSERT (ptr);
+ ASSERT (stack);
+ *((void**)ptr) = *stack;
+ *stack = ptr;
+}
static inline void*
-suba_addr (const struct allocator *suba, const ref_t ref)
+unused_pop (void **stack)
{
- ASSERT (suba);
- ASSERT (ref >= HDRSIZ);
- ASSERT (ref < suba->size);
- return (char*)suba + ref;
+ void *ptr;
+ ASSERT (stack);
+ ptr = *stack;
+ *stack = *(void**)ptr;
+ return ptr;
+
}
-static inline ref_t
-suba_ref (const struct allocator *suba, const void *ptr)
+static inline void*
+unused_peek (void **stack)
{
- ASSERT (suba);
- ASSERT (ptr);
- ASSERT ((char*)ptr >= (char*)suba + HDRSIZ);
- ASSERT ((char*)ptr < (char*)suba + suba->size);
- return (char*)ptr - (char*)suba;
+ ASSERT (stack);
+ return *stack;
}
-static struct allocator *
-suba_init (void *mem, size_t size)
+/* -----------------------------------------------------------------------------
+ * POOL META DATA ALLOCATION
+ *
+ * A pool for memory meta data. We allocate fixed size blocks. There are actually
+ * two different structures stored in this pool: Cell and Block. Cell is allocated
+ * way more often, and is bigger so we just allocate that size for both.
+ */
+
+/* Pool allocates this data type */
+typedef struct _Item {
+ union {
+ Cell cell;
+ Block block;
+ };
+} Item;
+
+typedef struct _Pool {
+ struct _Pool *next; /* Next pool in list */
+ size_t length; /* Length in bytes of the pool */
+ size_t used; /* Number of cells used in pool */
+ void *unused; /* Unused stack of unused stuff */
+ size_t n_items; /* Total number of items in pool */
+ Item items[1]; /* Actual items hang off here */
+} Pool;
+
+static Pool *all_pools = NULL;
+
+static void*
+pool_alloc (void)
{
- struct allocator *suba = mem;
- struct cell *c;
+ Pool *pool;
+ void *pages;
+ size_t len, i;
+
+ /* A pool with an available item */
+ for (pool = all_pools; pool; pool = pool->next) {
+ if (unused_peek (&pool->unused))
+ break;
+ }
+
+ /* Create a new pool */
+ if (pool == NULL) {
+ len = getpagesize () * 2;
+ pages = mmap (0, len, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+ if (pages == MAP_FAILED)
+ return NULL;
- ASSERT (mem != NULL);
- ASSERT (size > (HDRSIZ + POFF));
- ASSERT (ALIGN (sizeof (struct cell)) <= MINCELL);
+ /* Fill in the block header, and inlude in block list */
+ pool = pages;
+ pool->next = all_pools;
+ all_pools = pool;
+ pool->length = len;
+ pool->used = 0;
+ pool->unused = NULL;
+
+ /* Fill block with unused items */
+ pool->n_items = (len - sizeof (Pool)) / sizeof (Item);
+ for (i = 0; i < pool->n_items; ++i)
+ unused_push (&pool->unused, pool->items + i);
+ }
+
+ ++pool->used;
+ ASSERT (unused_peek (&pool->unused));
+ return memset (unused_pop (&pool->unused), 0, sizeof (Item));
+}
+
+static void
+pool_free (void* item)
+{
+ Pool *pool, **at;
+ char *ptr, *beg, *end;
+
+ ptr = item;
+
+ /* Find which block this one belongs to */
+ for (at = &all_pools, pool = *at; pool; at = &pool->next, pool = *at) {
+ beg = (char*)pool->items;
+ end = (char*)pool + pool->length - sizeof (Item);
+ if (ptr >= beg && ptr <= end) {
+ ASSERT ((ptr - beg) % sizeof (Item) == 0);
+ break;
+ }
+ }
+
+ /* Otherwise invalid meta */
+ ASSERT (pool && *at);
+ ASSERT (pool->used > 0);
+
+ /* No more meta cells used in this block, remove from list, destroy */
+ if (pool->used == 1) {
+ *at = pool->next;
+ munmap (pool, pool->length);
+ return;
+ }
+
+ --pool->used;
+ memset (item, 0xCD, sizeof (Item));
+ unused_push (&pool->unused, item);
+}
- memset(suba, 0, HDRSIZ);
- memcpy(suba->magic, SUBA_MAGIC, 8);
- suba->tail = HDRSIZ;
- suba->size = size;
+static int
+pool_valid (void* item)
+{
+ Pool *pool;
+ char *ptr, *beg, *end;
+
+ ptr = item;
+
+ /* Find which block this one belongs to */
+ for (pool = all_pools; pool; pool = pool->next) {
+ beg = (char*)pool->items;
+ end = (char*)pool + pool->length - sizeof (Item);
+ if (ptr >= beg && ptr <= end)
+ return (pool->used && (ptr - beg) % sizeof (Item) == 0);
+ }
+
+ return 0;
+}
- c = suba_addr (suba, HDRSIZ);
- c->size = size - (HDRSIZ + POFF);
- c->next = suba->tail;
+/* -----------------------------------------------------------------------------
+ * SEC ALLOCATION
+ *
+ * Each memory cell begins and ends with a pointer to its metadata.
+ *
+ */
- return suba;
+static inline size_t
+sec_size_to_words (size_t length)
+{
+ return (length % sizeof (void*) ? 1 : 0) + (length / sizeof (void*));
}
-static void *
-suba_alloc(struct allocator *suba, size_t size)
+static inline void
+sec_write_guards (Cell *cell)
{
- struct cell *c1, *c2, *c3;
- size_t s = size;
+ ((void**)cell->words)[0] = (void*)cell;
+ ((void**)cell->words)[cell->n_words - 1] = (void*)cell;
+}
- size = size < MINCELL ? MINCELL : ALIGN (size);
+static inline void
+sec_check_guards (Cell *cell)
+{
+ ASSERT(((void**)cell->words)[0] == (void*)cell);
+ ASSERT(((void**)cell->words)[cell->n_words - 1] == (void*)cell);
+}
- c2 = suba_addr (suba, suba->tail);
- for ( ;; ) {
- c1 = c2;
- c2 = suba_addr (suba, c1->next);
- if (c2->size >= size)
- break; /* found a cell large enough */
- if (c1->next == suba->tail)
- return NULL;
+static void
+sec_insert_cell_ring (Cell **ring, Cell *cell)
+{
+ ASSERT (ring);
+ ASSERT (cell);
+ ASSERT (cell != *ring);
+ ASSERT (cell->next == NULL);
+ ASSERT (cell->prev == NULL);
+
+ /* Insert back into the mix of available memory */
+ if (*ring) {
+ cell->next = (*ring)->next;
+ cell->prev = (*ring)->prev;
+ cell->next->prev = cell;
+ cell->prev->next = cell;
+ } else {
+ cell->next = cell;
+ cell->prev = cell;
}
+
+ *ring = cell;
+}
+
+static void
+sec_remove_cell_ring (Cell **ring, Cell *cell)
+{
+ ASSERT (ring);
+ ASSERT (*ring);
+ ASSERT (cell->next);
+ ASSERT (cell->prev);
+
+ if (cell == *ring) {
+ /* The last meta? */
+ if (cell->next == cell) {
+ ASSERT (cell->prev == cell);
+ *ring = NULL;
- if ((c2->size - size) > MINCELL) {
- /* split new cell */
- c3 = (struct cell *)(C2P(c2) + size);
- c3->size = c2->size - (size + POFF);
- if (c1 == c2) {
- c1 = c3;
+ /* Just pointing to this meta */
} else {
- c3->next = c2->next;
+ ASSERT (cell->prev != cell);
+ *ring = cell->next;
}
- c1->next = suba_ref (suba, c3);
- c2->size = size;
- if (c2 == suba_addr (suba, suba->tail))
- suba->tail = suba_ref (suba, c3);
- } else if (c1->next == suba->tail) {
- /* never use the last cell! */
- } else {
- /* use the entire cell */
- c1->next = c2->next;
}
- suba->alloc_total += POFF + c2->size;
- suba->size_total += s;
-
- c2->magic = CELL_MAGIC;
- DEBUG_ALLOC ("gkr-secure-memory: allocated ", (unsigned long)size);
-
- /* TODO: Fix suba, so always allocates zero */
- memset (C2P(c2), 0, c2->size);
+ cell->next->prev = cell->prev;
+ cell->prev->next = cell->next;
+ cell->next = cell->prev = NULL;
- return C2P(c2);
+ ASSERT (*ring != cell);
}
-static void
-suba_free(void *suba0, void *ptr)
+static inline void*
+sec_cell_to_memory (Cell *cell)
{
- struct allocator *suba = suba0;
- struct cell *c1, *c2, *c3;
- volatile char *vp;
- size_t len;
- ref_t ref;
- int j1, j2;
+ return cell->words + 1;
+}
- if (!ptr)
- return;
+static inline int
+sec_is_valid_word (Block *block, word_t *word)
+{
+ return (word >= block->words && word < block->words + block->n_words);
+}
- c1 = suba_addr (suba, suba->tail);
+static inline void*
+sec_clear_memory (void *memory, size_t from, size_t to)
+{
+ ASSERT (from <= to);
+ memset ((char*)memory + from, 0, to - from);
+ return memory;
+}
- /* Find out what cell we're talking about */
- c2 = P2C(ptr);
- ref = suba_ref (suba, c2);
- if (c2->magic != CELL_MAGIC) {
- ASSERT(0 && "invalid memory pointer passed to gkr-secure-memory");
- return;
- }
-
- /* Clear out memory */
- vp = (volatile char*)ptr;
- len = c2->size;
- while (len) {
- *vp = 0xaa;
- vp++;
- len--;
- }
+static Cell*
+sec_neighbor_before (Block *block, Cell *cell)
+{
+ word_t *word;
+
+ ASSERT (cell);
+ ASSERT (block);
+
+ word = cell->words - 1;
+ if (!sec_is_valid_word (block, word))
+ return NULL;
- suba->free_total += POFF + c2->size;
- suba->alloc_total -= (POFF + c2->size);
+ cell = *word;
+ sec_check_guards (cell);
+ return cell;
+}
- c2->magic = 0;
- DEBUG_ALLOC ("gkr-secure-memory: freed ", (unsigned long)c2->size);
+static Cell*
+sec_neighbor_after (Block *block, Cell *cell)
+{
+ word_t *word;
- /* splice the cell back into the list */
- if (c2 > c1) { /* append to end of list */
- if (ISADJ(c1,c2)) { /* join with last cell */
- c1->size += POFF + c2->size;
- return;
- }
- c2->next = c1->next;
- suba->tail = c1->next = ref;
- return;
- }
+ ASSERT (cell);
+ ASSERT (block);
+
+ word = cell->words + cell->n_words;
+ if (!sec_is_valid_word (block, word))
+ return NULL;
- while (c1->next < ref) /* find insertion point */
- c1 = suba_addr (suba, c1->next);
- c3 = suba_addr (suba, c1->next);
-
- j1 = ISADJ(c1,c2); /* c1 and c2 need to be joined */
- j2 = ISADJ(c2,c3); /* c2 and c3 need to be joined */
-
- if (j1) {
- if (j2) { /* splice all three cells together */
- if (suba_ref (suba, c3) == suba->tail)
- suba->tail = suba_ref (suba, c1);
- c1->next = c3->next;
- c1->size += POFF + c3->size;
- }
- c1->size += POFF + c2->size;
- } else {
- if (j2) {
- if (suba_ref (suba, c3) == suba->tail)
- suba->tail = ref;
- c2->next = c3->next == suba_ref (suba, c3) ? ref : c3->next;
- c2->size += POFF + c3->size;
- } else {
- c2->next = c1->next;
- }
- c1->next = ref;
- }
+ cell = *word;
+ sec_check_guards (cell);
+ return cell;
}
-static void *
-suba_realloc(struct allocator *suba, void *ptr, size_t size)
+static void*
+sec_alloc (Block *block, size_t length)
{
- struct cell *c;
- void *p;
+ Cell *cell, *other;
+ size_t n_words;
+
+ ASSERT (block);
+ ASSERT (length);
- if (ptr == NULL)
- return suba_alloc(suba, size);
- if (size == 0) {
- suba_free(suba, ptr);
+ if (!block->unused)
return NULL;
+
+ /*
+ * Each memory allocation is aligned to a pointer size, and
+ * then, sandwidched between two pointers to its meta data.
+ * These pointers also act as guards.
+ *
+ * We allocate memory in units of sizeof (void*)
+ */
+
+ n_words = sec_size_to_words (length) + 2;
+
+ /* Look for a cell of at least our required size */
+ cell = block->unused;
+ while (cell->n_words < n_words) {
+ cell = cell->next;
+ if (cell == block->unused) {
+ cell = NULL;
+ break;
+ }
}
- c = P2C(ptr);
- if (c->size < size || (c->size - ALIGN(size)) > MINCELL) {
- p = suba_alloc(suba, size);
- } else {
- return ptr;
- }
- if (p) {
- memcpy(p, ptr, c->size);
- suba_free(suba, ptr);
+
+ if (!cell)
+ return NULL;
+
+ ASSERT (cell->allocated == 0);
+ ASSERT (cell->prev);
+ ASSERT (cell->words);
+ sec_check_guards (cell);
+
+ /* Steal from the cell if it's too long */
+ if (cell->n_words > n_words + WASTE) {
+ other = pool_alloc ();
+ if (!other)
+ return NULL;
+ other->n_words = n_words;
+ other->words = cell->words;
+ cell->n_words -= n_words;
+ cell->words += n_words;
+
+ sec_write_guards (other);
+ sec_write_guards (cell);
+
+ cell = other;
}
-
- return p;
+
+ if (cell->next)
+ sec_remove_cell_ring (&block->unused, cell);
+
+ ++block->used;
+ cell->allocated = length;
+ return memset (sec_cell_to_memory (cell), 0, cell->allocated);
}
-static int
-suba_print_cell(struct allocator *suba, const char *msg, struct cell *c)
+static void*
+sec_free (Block *block, void *memory)
{
- ref_t ref = suba_ref (suba, c);
- if (ref >= ALIGN(sizeof *suba) && (ref + POFF + c->size) <= 10000000) {
- fprintf(stderr, "%s: %8u-%-8u %8u %-8u\n", msg,
- (unsigned int)ref, (unsigned int)(ref + POFF + c->size),
- (unsigned int)c->size, (unsigned int)c->next);
- } else {
- fprintf(stderr, "%s: %8u-err %8u %-8u\n", msg,
- (unsigned int)ref, (unsigned int)c->size,
- (unsigned int)c->next);
- return 0;
- }
- return 1;
+ Cell *cell, *other;
+ word_t *word;
+
+ ASSERT (block);
+ ASSERT (memory);
+
+ /* Lookup the meta for this memory block (using guard pointer) */
+ word = memory;
+ ASSERT (sec_is_valid_word (block, word - 1));
+ ASSERT (pool_valid (*(word - 1)));
+ cell = *(word - 1);
+
+ sec_check_guards (cell);
+ sec_clear_memory (memory, 0, cell->allocated);
+
+ sec_check_guards (cell);
+ ASSERT (cell->next == NULL);
+ ASSERT (cell->prev == NULL);
+ ASSERT (cell->allocated > 0);
+
+ /* Find previous unallocated neighbor, and merge if possible */
+ other = sec_neighbor_before (block, cell);
+ if (other && other->allocated == 0) {
+ ASSERT (other->next && other->prev);
+ other->n_words += cell->n_words;
+ sec_write_guards (other);
+ pool_free (cell);
+ cell = other;
+ }
+
+ /* Find next unallocated neighbor, and merge if possible */
+ other = sec_neighbor_after (block, cell);
+ if (other && other->allocated == 0) {
+ ASSERT (other->next && other->prev);
+ other->n_words += cell->n_words;
+ other->words = cell->words;
+ if (cell->next)
+ sec_remove_cell_ring (&block->unused, cell);
+ sec_write_guards (other);
+ pool_free (cell);
+ cell = other;
+ }
+
+ /* Add to the unused list if not already there */
+ if (!cell->next)
+ sec_insert_cell_ring (&block->unused, cell);
+
+ cell->allocated = 0;
+ --block->used;
+ return NULL;
}
-static int
-suba_print_free_list(struct allocator *suba)
+static void*
+sec_realloc (Block *block, void *memory, size_t length)
{
- struct cell *c;
- char buf[10];
- int count = 0;
- int ret = 1;
+ Cell *cell, *other;
+ word_t *word;
+ size_t n_words;
+ size_t valid;
+ void *alloc;
+
+ /* Standard realloc behavior, should have been handled elsewhere */
+ ASSERT (memory != NULL);
+ ASSERT (length > 0);
+
+ /* Dig out where the meta should be */
+ word = memory;
+ ASSERT (sec_is_valid_word (block, word - 1));
+ ASSERT (pool_valid (*(word - 1)));
+ cell = *(word - 1);
+
+ /* Validate that it's actually for real */
+ sec_check_guards (cell);
+ ASSERT (cell->allocated > 0);
+ ASSERT (cell->next == NULL);
+ ASSERT (cell->prev == NULL);
+
+ /* The amount of valid data */
+ valid = cell->allocated;
+
+ /* How many words we actually want */
+ n_words = sec_size_to_words (length) + 2;
+
+ /* Less memory is required */
+ if (n_words <= cell->n_words) {
+
+ /* TODO: No shrinking behavior yet */
+ cell->allocated = length;
+ return sec_clear_memory (sec_cell_to_memory (cell), valid, length);
+ }
+
+ /* Need braaaaaiiiiiinsss... */
+ while (cell->n_words < n_words) {
+
+ /* See if we have a neighbor who can give us some memory */
+ other = sec_neighbor_after (block, cell);
+ if (!other || other->allocated != 0)
+ break;
+
+ /* Eat the whole neighbor if not too big */
+ if (n_words - cell->n_words >= other->n_words + WASTE) {
+ cell->n_words += other->n_words;
+ sec_write_guards (cell);
+ sec_remove_cell_ring (&block->unused, other);
+ pool_free (other);
- c = suba_addr (suba, suba->tail);
- while (c->next < suba->tail) {
- c = suba_addr (suba, c->next);
- sprintf(buf, "%d", count++);
- if (!suba_print_cell(suba, buf, c)) {
- ret = 0;
+ /* Steal from the neighbor */
+ } else {
+ other->words += n_words - cell->n_words;
+ other->n_words -= n_words - cell->n_words;
+ sec_write_guards (other);
+ cell->n_words = n_words;
+ sec_write_guards (cell);
}
}
- c = suba_addr (suba, c->next);
- sprintf(buf, "%d", count++);
- if (!suba_print_cell(suba, buf, c)) {
- ret = 0;
+
+ if (cell->n_words >= n_words) {
+ cell->allocated = length;
+ return sec_clear_memory (sec_cell_to_memory (cell), valid, length);
}
-
- return ret;
+
+ /* That didn't work, try alloc/free */
+ alloc = sec_alloc (block, length);
+ if (alloc) {
+ memcpy (alloc, memory, valid);
+ sec_free (block, memory);
+ }
+
+ return alloc;
}
+
static size_t
-suba_allocation_size (struct allocator *suba, void *ptr)
+sec_allocated (Block *block, void *memory)
{
- struct cell *c = P2C(ptr);
- if (c->magic != CELL_MAGIC) {
- ASSERT(0 && "invalid memory pointer passed to gkr-secure-memory");
- return 0;
- }
- return c->size;
+ Cell *cell;
+ word_t *word;
+
+ ASSERT (block);
+ ASSERT (memory);
+
+ /* Lookup the meta for this memory block (using guard pointer) */
+ word = memory;
+ ASSERT (sec_is_valid_word (block, word - 1));
+ ASSERT (pool_valid (*(word - 1)));
+ cell = *(word - 1);
+
+ sec_check_guards (cell);
+ ASSERT (cell->next == NULL);
+ ASSERT (cell->prev == NULL);
+ ASSERT (cell->allocated > 0);
+
+ return cell->allocated;
}
/* -----------------------------------------------------------------------------
- * PAGE SOURCE -- Where blocks of locked memory pages come from.
+ * LOCKED MEMORY
*/
-
-static int lock_warning = 1;
static void*
-get_locked_pages (unsigned long *sz)
+sec_acquire_pages (unsigned long *sz)
{
void *pages;
unsigned long pgsize;
@@ -430,7 +664,7 @@
}
static void
-rel_locked_pages (void *pages, unsigned long sz)
+sec_release_pages (void *pages, unsigned long sz)
{
ASSERT (pages);
ASSERT (sz % getpagesize () == 0);
@@ -453,276 +687,282 @@
* MANAGE DIFFERENT BLOCKS
*/
-typedef struct _MemBlock {
- unsigned long size;
- struct allocator *suba;
- struct _MemBlock *next;
-} MemBlock;
-
-static MemBlock *most_recent_block = NULL;
+static Block *all_blocks = NULL;
-static MemBlock*
-block_create (unsigned long size)
+static Block*
+sec_block_create (unsigned long size)
{
- MemBlock *bl;
- void *blmem;
+ Block *block;
+ Cell *cell;
#if FORCE_FALLBACK_MEMORY
/* We can force all all memory to be malloced */
return NULL;
#endif
- size += sizeof (MemBlock);
-
+ block = pool_alloc ();
+ if (!block)
+ return NULL;
+
+ cell = pool_alloc ();
+ if (!cell) {
+ pool_free (block);
+ return NULL;
+ }
+
/* The size above is a minimum, we're free to go bigger */
if (size < DEFAULT_BLOCK_SIZE)
size = DEFAULT_BLOCK_SIZE;
- blmem = get_locked_pages (&size);
- if (!blmem)
+ block->n_words = size / sizeof (word_t);
+ block->words = sec_acquire_pages (&size);
+ if (!block->words) {
+ pool_free (block);
+ pool_free (cell);
return NULL;
-
- bl = (MemBlock*)blmem;
- bl->size = size;
- bl->suba = suba_init (((unsigned char*)blmem) + sizeof (MemBlock),
- size - sizeof (MemBlock));
- ASSERT (bl->suba);
+ }
- bl->next = most_recent_block;
- most_recent_block = bl;
+ /* The first cell to allocate from */
+ cell->words = block->words;
+ cell->n_words = block->n_words;
+ cell->allocated = 0;
+ sec_write_guards (cell);
+ sec_insert_cell_ring (&block->unused, cell);
- return bl;
+ block->next = all_blocks;
+ all_blocks = block;
+
+ return block;
}
static void
-block_destroy (MemBlock *bl)
+sec_block_destroy (Block *block)
{
- MemBlock *b;
-
- ASSERT (bl && bl->suba);
- ASSERT (bl->size > 0);
- ASSERT (bl->suba->alloc_total == 0);
+ Block *bl, **at;
+ Cell *cell;
+
+ ASSERT (block);
+ ASSERT (block->words);
+ ASSERT (block->used == 0);
- /* Is the most recent block, simple */
- if (bl == most_recent_block) {
- most_recent_block = bl->next;
-
- /* Take it out of our list */
- } else {
- for (b = most_recent_block; b; b = b->next) {
- if (b->next == bl) {
- b->next = bl->next;
- break;
- }
+ /* Remove from the list */
+ for (at = &all_blocks, bl = *at; bl; at = &bl->next, bl = *at) {
+ if (bl == block) {
+ *at = block->next;
+ break;
}
- ASSERT (b != NULL && "couldn't find memory block in list");
}
- /* Memory is all in one block, nothing fancy to free */
- rel_locked_pages(bl, bl->size);
-}
+ /* Must have been found */
+ ASSERT (bl == block);
-static int
-block_belongs (MemBlock *bl, const void *p)
-{
- ASSERT (bl);
- ASSERT (bl->size > 0);
+ /* Release all the meta data cells */
+ while (block->unused) {
+ cell = block->unused;
+ sec_remove_cell_ring (&block->unused, cell);
+ pool_free (cell);
+ }
- /* This does not check for invalid memory */
- return ((char*)p) >= ((char*)bl) &&
- ((char*)p) < (((char*)bl) + bl->size);
+ /* Release all pages of secure memory */
+ sec_release_pages (block->words, block->n_words * sizeof (word_t));
+
+ pool_free (block);
}
+/* ------------------------------------------------------------------------
+ * PUBLIC FUNCTIONALITY
+ */
+
void*
-egg_secure_alloc (unsigned long sz)
+egg_secure_alloc (size_t length)
{
- return egg_secure_alloc_full (sz, GKR_SECURE_USE_FALLBACK);
+ return egg_secure_alloc_full (length, GKR_SECURE_USE_FALLBACK);
}
void*
-egg_secure_alloc_full (unsigned long sz, int flags)
+egg_secure_alloc_full (size_t length, int flags)
{
- MemBlock *bl;
- void *p = NULL;
+ Block *block;
+ void *memory = NULL;
- if (sz > 0xFFFFFFFF / 2) {
- fprintf (stderr, "tried to allocate an insane amount of memory: %lu\n", sz);
+ if (length > 0xFFFFFFFF / 2) {
+ fprintf (stderr, "tried to allocate an insane amount of memory: %lu\n", length);
return NULL;
}
DO_LOCK ();
- for (bl = most_recent_block; bl; bl = bl->next) {
- p = suba_alloc (bl->suba, sz);
- if (p)
+ for (block = all_blocks; block; block = block->next) {
+ memory = sec_alloc (block, length);
+ if (memory)
break;
}
/* None of the current blocks have space, allocate new */
- if (!p) {
- bl = block_create (sz);
- if (bl) {
- p = suba_alloc (bl->suba, sz);
- ASSERT (p);
- }
+ if (!memory) {
+ block = sec_block_create (length);
+ if (block)
+ memory = sec_alloc (block, length);
}
DO_UNLOCK ();
- if (!p && (flags & GKR_SECURE_USE_FALLBACK)) {
- p = egg_memory_fallback (NULL, sz);
- if (p) /* Our returned memory is always zeroed */
- memset (p, 0, sz);
+ if (!memory && (flags & GKR_SECURE_USE_FALLBACK)) {
+ memory = egg_memory_fallback (NULL, length);
+ if (memory) /* Our returned memory is always zeroed */
+ memset (memory, 0, length);
}
- if (!p)
+ if (!memory)
errno = ENOMEM;
- return p;
+ return memory;
}
void*
-egg_secure_realloc (void *p, unsigned long sz)
+egg_secure_realloc (void *memory, size_t length)
{
- return egg_secure_realloc_full (p, sz, GKR_SECURE_USE_FALLBACK);
+ return egg_secure_realloc_full (memory, length, GKR_SECURE_USE_FALLBACK);
}
void*
-egg_secure_realloc_full (void *p, unsigned long sz, int flags)
+egg_secure_realloc_full (void *memory, unsigned long length, int flags)
{
- MemBlock *bl = NULL;
- unsigned long oldsz = 0;
+ Block *block = NULL;
+ size_t previous = 0;
int donew = 0;
- void *n = NULL;
+ void *alloc = NULL;
- if (sz > 0xFFFFFFFF / 2) {
- fprintf (stderr, "tried to allocate an insane amount of memory: %lu\n", sz);
+ if (length > 0xFFFFFFFF / 2) {
+ fprintf (stderr, "tried to allocate an insane amount of memory: %lu\n", length);
ASSERT (0 && "tried to allocate an insane amount of memory");
return NULL;
}
- if (p == NULL)
- return egg_secure_alloc_full (sz, flags);
- if (!sz) {
- egg_secure_free_full (p, flags);
+ if (memory == NULL)
+ return egg_secure_alloc_full (length, flags);
+ if (!length) {
+ egg_secure_free_full (memory, flags);
return NULL;
}
DO_LOCK ();
/* Find out where it belongs to */
- for (bl = most_recent_block; bl; bl = bl->next) {
- if (block_belongs (bl, p)) {
- oldsz = suba_allocation_size (bl->suba, p);
- n = suba_realloc (bl->suba, p, sz);
+ for (block = all_blocks; block; block = block->next) {
+ if (sec_is_valid_word (block, memory)) {
+ previous = sec_allocated (block, memory);
+ alloc = sec_realloc (block, memory, length);
break;
}
}
/* If it didn't work we may need to allocate a new block */
- if (bl && !n)
+ if (block && !alloc)
donew = 1;
- if (bl && bl->suba->alloc_total == 0)
- block_destroy (bl);
+ if (block && block->used == 0)
+ sec_block_destroy (block);
DO_UNLOCK ();
- if (!bl) {
+ if (!block) {
if ((flags & GKR_SECURE_USE_FALLBACK)) {
/*
* In this case we can't zero the returned memory,
* because we don't know what the block size was.
*/
- return egg_memory_fallback (p, sz);
+ return egg_memory_fallback (memory, length);
} else {
- fprintf (stderr, "memory does not belong to gnome-keyring: 0x%08lx\n", (unsigned long)p);
+ fprintf (stderr, "memory does not belong to gnome-keyring: 0x%08lx\n", (unsigned long)memory);
ASSERT (0 && "memory does does not belong to gnome-keyring");
return NULL;
}
}
if (donew) {
- n = egg_secure_alloc_full (sz, flags);
- if (n) {
- memcpy (n, p, oldsz);
- egg_secure_free_full (p, flags);
+ alloc = egg_secure_alloc_full (length, flags);
+ if (alloc) {
+ memcpy (alloc, memory, previous);
+ egg_secure_free_full (memory, flags);
}
}
- if (!n)
+ if (!alloc)
errno = ENOMEM;
- return n;
+ return alloc;
}
void
-egg_secure_free (void *p)
+egg_secure_free (void *memory)
{
- egg_secure_free_full (p, GKR_SECURE_USE_FALLBACK);
+ egg_secure_free_full (memory, GKR_SECURE_USE_FALLBACK);
}
void
-egg_secure_free_full (void *p, int flags)
+egg_secure_free_full (void *memory, int flags)
{
- MemBlock *bl = NULL;
+ Block *block = NULL;
+
+ if (memory == NULL)
+ return;
DO_LOCK ();
/* Find out where it belongs to */
- for (bl = most_recent_block; bl; bl = bl->next) {
- if (block_belongs (bl, p)) {
- suba_free (bl->suba, p);
+ for (block = all_blocks; block; block = block->next) {
+ if (sec_is_valid_word (block, memory)) {
+ sec_free (block, memory);
break;
}
}
- if (bl && bl->suba->alloc_total == 0)
- block_destroy (bl);
+ if (block && block->used == 0)
+ sec_block_destroy (block);
DO_UNLOCK ();
- if (!bl) {
+ if (!block) {
if ((flags & GKR_SECURE_USE_FALLBACK)) {
- egg_memory_fallback (p, 0);
+ egg_memory_fallback (memory, 0);
} else {
- fprintf (stderr, "memory does not belong to gnome-keyring: 0x%08lx\n", (unsigned long)p);
+ fprintf (stderr, "memory does not belong to gnome-keyring: 0x%08lx\n", (unsigned long)memory);
ASSERT (0 && "memory does does not belong to gnome-keyring");
}
}
}
int
-egg_secure_check (const void *p)
+egg_secure_check (const void *memory)
{
- MemBlock *bl = NULL;
+ Block *block = NULL;
DO_LOCK ();
/* Find out where it belongs to */
- for (bl = most_recent_block; bl; bl = bl->next) {
- if (block_belongs (bl, p))
+ for (block = all_blocks; block; block = block->next) {
+ if (sec_is_valid_word (block, (word_t*)memory))
break;
}
DO_UNLOCK ();
- return bl == NULL ? 0 : 1;
+ return block == NULL ? 0 : 1;
}
void
egg_secure_dump_blocks (void)
{
- MemBlock *bl = NULL;
+ Block *block = NULL;
DO_LOCK ();
/* Find out where it belongs to */
- for (bl = most_recent_block; bl; bl = bl->next) {
+ for (block = all_blocks; block; block = block->next) {
fprintf (stderr, "----------------------------------------------------\n");
- fprintf (stderr, " BLOCK at: 0x%08lx len: %lu\n", (unsigned long)bl, bl->size);
+ fprintf (stderr, " BLOCK at: 0x%08lx len: %lu\n", (unsigned long)block, block->n_words * sizeof (word_t));
fprintf (stderr, "\n");
- suba_print_free_list (bl->suba);
}
DO_UNLOCK ();
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