StatefulMem* functions should be library functions.

We want the BIOS to implement the stub functions, but that shouldn't include
our StatefulMem* functions.

Also, we ensure that we don't accidently use native linux functions instead
of the stub functions.

Review URL: http://codereview.chromium.org/2255006
This commit is contained in:
Bill Richardson
2010-05-27 12:27:32 -07:00
parent f5db4b86fa
commit d6ff721eb0
10 changed files with 126 additions and 84 deletions

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@@ -19,7 +19,6 @@ void error(const char *format, ...);
/* Outputs debug/warning messages. */ /* Outputs debug/warning messages. */
void debug(const char *format, ...); void debug(const char *format, ...);
#define assert(expr) do { if (!(expr)) { \ #define assert(expr) do { if (!(expr)) { \
error("assert fail: %s at %s:%d\n", \ error("assert fail: %s at %s:%d\n", \
#expr, __FILE__, __LINE__); }} while(0) #expr, __FILE__, __LINE__); }} while(0)
@@ -58,42 +57,14 @@ void* Memset(void *dest, const uint8_t c, size_t n);
*/ */
int SafeMemcmp(const void* s1, const void* s2, size_t n); int SafeMemcmp(const void* s1, const void* s2, size_t n);
/* Track remaining data to be read in a buffer. */ /* Ensure that only our stub implementations are used, not standard C */
typedef struct MemcpyState { #ifndef _STUB_IMPLEMENTATION_
void* remaining_buf; #define malloc _do_not_use_standard_malloc
uint64_t remaining_len; /* Remaining length of the buffer. */ #define free _do_not_use_standard_free
uint8_t overrun; /* Flag set to 1 when an overrun occurs. */ #define memcmp _do_not_use_standard_memcmp
} MemcpyState; #define memcpy _do_not_use_standard_memcpy
#define memset _do_not_use_standard_memset
/* Copy [len] bytes into [dst] only if there's enough data to read according #endif
* to [state].
* On success, return [dst] and update [state].
* On failure, return NULL, set remaining len in state to -1.
*
* Useful for iterating through a binary blob to populate a struct. After the
* first failure (buffer overrun), successive calls will always fail.
*/
void* StatefulMemcpy(MemcpyState* state, void* dst, uint64_t len);
/* Like StatefulMemcpy() but copies in the opposite direction, populating
* data from [src] into the buffer encapsulated in state [state].
* On success, return [src] and update [state].
* On failure, return NULL, set remaining_len in state to -1.
*
* Useful for iterating through a structure to populate a binary blob. After the
* first failure (buffer overrun), successive calls will always fail.
*/
const void* StatefulMemcpy_r(MemcpyState* state, const void* src, uint64_t len);
/* Like StatefulMemcpy_r() but fills a portion of the encapsulated buffer with
* a constant value.
* On success, return a meaningless but non-NULL pointer and updates [state].
* On failure, return NULL, set remaining_len in state to -1.
*
* After the first failure (buffer overrun), successive calls will always fail.
*/
const void* StatefulMemset_r(MemcpyState* state, const uint8_t val,
uint64_t len);
#endif /* VBOOT_REFERENCE_UTILITY_H_ */ #endif /* VBOOT_REFERENCE_UTILITY_H_ */

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@@ -6,7 +6,7 @@
*/ */
#include "cryptolib.h" #include "cryptolib.h"
#include "utility.h" #include "stateful_util.h"
int RSAProcessedKeySize(int algorithm) { int RSAProcessedKeySize(int algorithm) {
int key_len = siglen_map[algorithm]; /* Key length in int key_len = siglen_map[algorithm]; /* Key length in

View File

@@ -378,7 +378,7 @@ uint8_t* SHA256_final(SHA256_CTX* ctx) {
len_b = (ctx->tot_len + ctx->len) << 3; len_b = (ctx->tot_len + ctx->len) << 3;
pm_len = block_nb << 6; pm_len = block_nb << 6;
memset(ctx->block + ctx->len, 0, pm_len - ctx->len); Memset(ctx->block + ctx->len, 0, pm_len - ctx->len);
ctx->block[ctx->len] = 0x80; ctx->block[ctx->len] = 0x80;
UNPACK32(len_b, ctx->block + pm_len - 4); UNPACK32(len_b, ctx->block + pm_len - 4);
@@ -568,7 +568,7 @@ uint8_t* SHA512_final(SHA512_CTX* ctx)
len_b = (ctx->tot_len + ctx->len) << 3; len_b = (ctx->tot_len + ctx->len) << 3;
pm_len = block_nb << 7; pm_len = block_nb << 7;
memset(ctx->block + ctx->len, 0, pm_len - ctx->len); Memset(ctx->block + ctx->len, 0, pm_len - ctx->len);
ctx->block[ctx->len] = 0x80; ctx->block[ctx->len] = 0x80;
UNPACK32(len_b, ctx->block + pm_len - 4); UNPACK32(len_b, ctx->block + pm_len - 4);

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@@ -0,0 +1,55 @@
/* Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
/* Helper functions/wrappers for memory allocations, manipulation and
* comparison.
*/
#ifndef VBOOT_FIRMWARE_LIB_UTILITY_H_
#define VBOOT_FIRMWARE_LIB_UTILITY_H_
#include <stdint.h>
#include <string.h>
#include "utility.h"
/* Track remaining data to be read in a buffer. */
typedef struct MemcpyState {
void* remaining_buf;
uint64_t remaining_len; /* Remaining length of the buffer. */
uint8_t overrun; /* Flag set to 1 when an overrun occurs. */
} MemcpyState;
/* Copy [len] bytes into [dst] only if there's enough data to read according
* to [state].
* On success, return [dst] and update [state].
* On failure, return NULL, set remaining len in state to -1.
*
* Useful for iterating through a binary blob to populate a struct. After the
* first failure (buffer overrun), successive calls will always fail.
*/
void* StatefulMemcpy(MemcpyState* state, void* dst, uint64_t len);
/* Like StatefulMemcpy() but copies in the opposite direction, populating
* data from [src] into the buffer encapsulated in state [state].
* On success, return [src] and update [state].
* On failure, return NULL, set remaining_len in state to -1.
*
* Useful for iterating through a structure to populate a binary blob. After the
* first failure (buffer overrun), successive calls will always fail.
*/
const void* StatefulMemcpy_r(MemcpyState* state, const void* src, uint64_t len);
/* Like StatefulMemcpy_r() but fills a portion of the encapsulated buffer with
* a constant value.
* On success, return a meaningless but non-NULL pointer and updates [state].
* On failure, return NULL, set remaining_len in state to -1.
*
* After the first failure (buffer overrun), successive calls will always fail.
*/
const void* StatefulMemset_r(MemcpyState* state, const uint8_t val,
uint64_t len);
#endif /* VBOOT_FIRMWARE_LIB_UTILITY_H_ */

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@@ -0,0 +1,55 @@
/* Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*
* Stub implementations of utility functions which call their linux-specific
* equivalents.
*/
#include "stateful_util.h"
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
void* StatefulMemcpy(MemcpyState* state, void* dst,
uint64_t len) {
if (state->overrun)
return NULL;
if (len > state->remaining_len) {
state->overrun = 1;
return NULL;
}
Memcpy(dst, state->remaining_buf, len);
state->remaining_buf += len;
state->remaining_len -= len;
return dst;
}
const void* StatefulMemcpy_r(MemcpyState* state, const void* src,
uint64_t len) {
if (state->overrun)
return NULL;
if (len > state->remaining_len) {
state->overrun = 1;
return NULL;
}
Memcpy(state->remaining_buf, src, len);
state->remaining_buf += len;
state->remaining_len -= len;
return src;
}
const void* StatefulMemset_r(MemcpyState* state, const uint8_t val,
uint64_t len) {
if (state->overrun)
return NULL;
if (len > state->remaining_len) {
state->overrun = 1;
return NULL;
}
Memset(state->remaining_buf, val, len);
state->remaining_buf += len;
state->remaining_len -= len;
return state; // have to return something non-NULL
}

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@@ -6,6 +6,7 @@
* equivalents. * equivalents.
*/ */
#define _STUB_IMPLEMENTATION_
#include "utility.h" #include "utility.h"
#include <stdarg.h> #include <stdarg.h>
@@ -68,45 +69,3 @@ int SafeMemcmp(const void* s1, const void* s2, size_t n) {
return match; return match;
} }
void* StatefulMemcpy(MemcpyState* state, void* dst,
uint64_t len) {
if (state->overrun)
return NULL;
if (len > state->remaining_len) {
state->overrun = 1;
return NULL;
}
Memcpy(dst, state->remaining_buf, len);
state->remaining_buf += len;
state->remaining_len -= len;
return dst;
}
const void* StatefulMemcpy_r(MemcpyState* state, const void* src,
uint64_t len) {
if (state->overrun)
return NULL;
if (len > state->remaining_len) {
state->overrun = 1;
return NULL;
}
Memcpy(state->remaining_buf, src, len);
state->remaining_buf += len;
state->remaining_len -= len;
return src;
}
const void* StatefulMemset_r(MemcpyState* state, const uint8_t val,
uint64_t len) {
if (state->overrun)
return NULL;
if (len > state->remaining_len) {
state->overrun = 1;
return NULL;
}
Memset(state->remaining_buf, val, len);
state->remaining_buf += len;
state->remaining_len -= len;
return state; // have to return something non-NULL
}

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@@ -4,6 +4,7 @@
CC ?= gcc CC ?= gcc
INCLUDES += -I./include \ INCLUDES += -I./include \
-I$(FWDIR)/lib/include \
-I$(FWDIR)/lib/cryptolib/include \ -I$(FWDIR)/lib/cryptolib/include \
-I../common/include \ -I../common/include \
-I../misclibs/include -I../misclibs/include

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@@ -15,7 +15,7 @@
#include "cryptolib.h" #include "cryptolib.h"
#include "file_keys.h" #include "file_keys.h"
#include "signature_digest.h" #include "signature_digest.h"
#include "utility.h" #include "stateful_util.h"
/* Macro to determine the size of a field structure in the FirmwareImage /* Macro to determine the size of a field structure in the FirmwareImage
* structure. */ * structure. */

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@@ -4,6 +4,7 @@
CC ?= gcc CC ?= gcc
INCLUDES += -I./include \ INCLUDES += -I./include \
-I$(FWDIR)/lib/include \
-I$(FWDIR)/lib/cryptolib/include \ -I$(FWDIR)/lib/cryptolib/include \
-I../common/include \ -I../common/include \
-I../misclibs/include -I../misclibs/include

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@@ -19,7 +19,7 @@
#include "kernel_blob.h" #include "kernel_blob.h"
#include "rollback_index.h" #include "rollback_index.h"
#include "signature_digest.h" #include "signature_digest.h"
#include "utility.h" #include "stateful_util.h"
/* Macro to determine the size of a field structure in the KernelImage /* Macro to determine the size of a field structure in the KernelImage
* structure. */ * structure. */