[OpenOCD-devel] [PATCH]: e283cf6 flash/nor/stm32f1x: Added RDP Level 2 support

[gerrit]

This is an automated email from Gerrit.

Johannes Obermaier (***@aisec.fraunhofer.de) just uploaded a new patch set to Gerrit, which you can find at http://openocd.zylin.com/4111

-- gerrit

commit e283cf6fb8e156b79fb333cd845e31cfee1d9b0d
Author: Johannes Obermaier <***@aisec.fraunhofer.de>
Date: Mon May 1 17:06:12 2017 +0200

flash/nor/stm32f1x: Added RDP Level 2 support

Currently, only Flash Readout Protection Level 0 and 1 are supported. This patch adds Protection Level 2 support for STM32F0x and STM32F3x. STM32F1x does not support this protection level in hardware.
Protection Level 2 permanently locks the microcontroller's debug interface, thus providing a higher level of security.
Since this level is irreversible, the command "lock_irreversibly" was chosen. This should prevent users from unintentionally bricking their devices.

Change-Id: Ibe56473a3b218288699f5aa6282a43abc76c9592
Signed-off-by: Johannes Obermaier <***@aisec.fraunhofer.de>

diff --git a/src/flash/nor/stm32f1x.c b/src/flash/nor/stm32f1x.c
index d446707..dad4f9e 100644
--- a/src/flash/nor/stm32f1x.c
+++ b/src/flash/nor/stm32f1x.c
@@ -105,6 +105,11 @@
#define FLASH_WRITE_TIMEOUT 10
#define FLASH_ERASE_TIMEOUT 100

+/* Flash read protection levels */
+
+#define FLASH_PROTECTION_LEVEL1 0x00
+#define FLASH_PROTECTION_LEVEL2 0xCC
+
struct stm32x_options {
uint16_t RDP;
uint16_t user_options;
@@ -130,6 +135,7 @@ static int stm32x_mass_erase(struct flash_bank *bank);
static int stm32x_get_device_id(struct flash_bank *bank, uint32_t *device_id);
static int stm32x_write_block(struct flash_bank *bank, const uint8_t *buffer,
uint32_t offset, uint32_t count);
+static int stm32x_rdp_set_lock_level(const unsigned int lock_rdp, struct command_invocation *cmd);

/* flash bank stm32x <base> <size> 0 0 <target#>
*/
@@ -1278,9 +1284,8 @@ static int get_stm32x_info(struct flash_bank *bank, char *buf, int buf_size)
return ERROR_OK;
}

-COMMAND_HANDLER(stm32x_handle_lock_command)
+static int stm32x_rdp_set_lock_level(const unsigned int lock_rdp, struct command_invocation *cmd)
{
- struct target *target = NULL;
struct stm32x_flash_bank *stm32x_info = NULL;

if (CMD_ARGC < 1)
@@ -1293,7 +1298,7 @@ COMMAND_HANDLER(stm32x_handle_lock_command)

stm32x_info = bank->driver_priv;

- target = bank->target;
+ struct target *target = bank->target;

if (target->state != TARGET_HALTED) {
LOG_ERROR("Target not halted");
@@ -1310,18 +1315,66 @@ COMMAND_HANDLER(stm32x_handle_lock_command)
}

/* set readout protection */
- stm32x_info->option_bytes.RDP = 0;
+ stm32x_info->option_bytes.RDP = lock_rdp;

if (stm32x_write_options(bank) != ERROR_OK) {
command_print(CMD_CTX, "stm32x failed to lock device");
return ERROR_OK;
}

- command_print(CMD_CTX, "stm32x locked");
+ /* STM32F1x has a different default RDP, compared to STM32F0x and STM32F3x */
+ if ((stm32x_info->default_rdp & 0xFF) == lock_rdp) {
+ command_print(CMD_CTX, "stm32x unlocked");
+ } else if (FLASH_PROTECTION_LEVEL2 == lock_rdp) {
+ command_print(CMD_CTX, "stm32x locked to level 2");
+ } else {
+ /* everything else maps to lock level 1 */
+ command_print(CMD_CTX, "stm32x locked to level 1");
+ }

return ERROR_OK;
}

+COMMAND_HANDLER(stm32x_handle_lock_lvl1_command)
+{
+ return stm32x_rdp_set_lock_level(FLASH_PROTECTION_LEVEL1, cmd);
+}
+
+COMMAND_HANDLER(stm32x_handle_lock_lvl2_command)
+{
+ int retval = ERROR_OK;
+ uint32_t device_id = 0;
+
+ /* get flash bank */
+ struct flash_bank *bank;
+ retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
+ if (ERROR_OK != retval)
+ return retval;
+
+ /* read stm32 device id register */
+ retval = stm32x_get_device_id(bank, &device_id);
+ if (retval != ERROR_OK)
+ return retval;
+
+ switch (device_id & 0xfff) {
+ case 0x410: /* medium density */
+ case 0x412: /* low density */
+ case 0x414: /* high density */
+ case 0x418: /* connectivity line density */
+ case 0x420: /* value line density */
+ case 0x428: /* value line High density */
+ case 0x430: /* xl line density (dual flash banks) */
+ command_print(CMD_CTX, "stm32x failed to lock device (Lock level 2 not supported for STM32F1x)");
+ break;
+
+ default:
+ retval = stm32x_rdp_set_lock_level(FLASH_PROTECTION_LEVEL2, cmd);
+ break;
+ }
+
+ return retval;
+}
+
COMMAND_HANDLER(stm32x_handle_unlock_command)
{
struct target *target = NULL;
@@ -1585,10 +1638,18 @@ COMMAND_HANDLER(stm32x_handle_mass_erase_command)
static const struct command_registration stm32x_exec_command_handlers[] = {
{
.name = "lock",
- .handler = stm32x_handle_lock_command,
+ .handler = stm32x_handle_lock_lvl1_command,
+ .mode = COMMAND_EXEC,
+ .usage = "bank_id",
+ .help = "Lock entire flash device, preserve debug interface. (Lock level 1)",
+ },
+ {
+ .name = "lock_irreversibly",
+ .handler = stm32x_handle_lock_lvl2_command,
.mode = COMMAND_EXEC,
.usage = "bank_id",
- .help = "Lock entire flash device.",
+ .help = "Lock the entire device irreversibly, disable debug interface permanently. "
+ "(Lock level 2, not supported by STM32F1x)",
},
{
.name = "unlock",

--