//-----------------------------------------------------------------------------
// Copyright (C) 2010 Hector Martin "marcan" <marcan@marcansoft.com>
//
// This code is licensed to you under the terms of the GNU GPL, version 2 or,
// at your option, any later version. See the LICENSE.txt file for the text of
// the license.
//-----------------------------------------------------------------------------
// ELF file flasher
//-----------------------------------------------------------------------------
#include "flash.h"
#define FLASH_START 0x100000
#ifdef HAS_512_FLASH
# define FLASH_SIZE (512*1024)
#else
# define FLASH_SIZE (256*1024)
#endif
#define FLASH_END (FLASH_START + FLASH_SIZE)
#define BOOTLOADER_SIZE 0x2000
#define BOOTLOADER_END (FLASH_START + BOOTLOADER_SIZE)
#define BLOCK_SIZE 0x200
static const uint8_t elf_ident[] = {
0x7f, 'E', 'L', 'F',
ELFCLASS32,
ELFDATA2LSB,
EV_CURRENT
};
// Turn PHDRs into flasher segments, checking for PHDR sanity and merging adjacent
// unaligned segments if needed
static int build_segs_from_phdrs(flash_file_t *ctx, FILE *fd, Elf32_Phdr *phdrs, uint16_t num_phdrs) {
Elf32_Phdr *phdr = phdrs;
flash_seg_t *seg;
uint32_t last_end = 0;
ctx->segments = calloc(sizeof(flash_seg_t) * num_phdrs, sizeof(uint8_t));
if (!ctx->segments) {
PrintAndLogEx(ERR, "Out of memory");
return -1;
}
ctx->num_segs = 0;
seg = ctx->segments;
PrintAndLogEx(SUCCESS, "Loading usable ELF segments:");
for (int i = 0; i < num_phdrs; i++) {
if (le32(phdr->p_type) != PT_LOAD) {
phdr++;
continue;
}
uint32_t vaddr = le32(phdr->p_vaddr);
uint32_t paddr = le32(phdr->p_paddr);
uint32_t filesz = le32(phdr->p_filesz);
uint32_t memsz = le32(phdr->p_memsz);
uint32_t offset = le32(phdr->p_offset);
uint32_t flags = le32(phdr->p_flags);
if (!filesz) {
phdr++;
continue;
}
PrintAndLogEx(SUCCESS, " "_YELLOW_("%d")": V 0x%08x P 0x%08x (0x%08x->0x%08x) [%c%c%c] @0x%x",
i, vaddr, paddr, filesz, memsz,
(flags & PF_R) ? 'R' : ' ',
(flags & PF_W) ? 'W' : ' ',
(flags & PF_X) ? 'X' : ' ',
offset);
if (filesz != memsz) {
PrintAndLogEx(ERR, "Error: PHDR file size does not equal memory size\n"
"(DATA+BSS PHDRs do not make sense on ROM platforms!)");
return -1;
}
if (paddr < last_end) {
PrintAndLogEx(ERR, "Error: PHDRs not sorted or overlap");
return -1;
}
if (paddr < FLASH_START || (paddr + filesz) > FLASH_END) {
PrintAndLogEx(ERR, "Error: PHDR is not contained in Flash");
return -1;
}
if (vaddr >= FLASH_START && vaddr < FLASH_END && (flags & PF_W)) {
PrintAndLogEx(ERR, "Error: Flash VMA segment is writable");
return -1;
}
uint8_t *data;
// make extra space if we need to move the data forward
data = calloc(filesz + BLOCK_SIZE, sizeof(uint8_t));
if (!data) {
PrintAndLogEx(ERR, "Error: Out of memory");
return -1;
}
if (fseek(fd, offset, SEEK_SET) < 0 || fread(data, 1, filesz, fd) != filesz) {
PrintAndLogEx(ERR, "Error while reading PHDR payload");
free(data);
return -1;
}
uint32_t block_offset = paddr & (BLOCK_SIZE - 1);
if (block_offset) {
if (ctx->num_segs) {
flash_seg_t *prev_seg = seg - 1;
uint32_t this_end = paddr + filesz;
uint32_t this_firstblock = paddr & ~(BLOCK_SIZE - 1);
uint32_t prev_lastblock = (last_end - 1) & ~(BLOCK_SIZE - 1);
if (this_firstblock == prev_lastblock) {
uint32_t new_length = this_end - prev_seg->start;
uint32_t this_offset = paddr - prev_seg->start;
uint32_t hole = this_offset - prev_seg->length;
uint8_t *new_data = calloc(new_length, sizeof(uint8_t));
if (!new_data) {
PrintAndLogEx(ERR, "Error: Out of memory");
free(data);
return -1;
}
memset(new_data, 0xff, new_length);
memcpy(new_data, prev_seg->data, prev_seg->length);
memcpy(new_data + this_offset, data, filesz);
PrintAndLogEx(INFO, "Note: Extending previous segment from 0x%x to 0x%x bytes",
prev_seg->length, new_length);
if (hole)
PrintAndLogEx(INFO, "Note: 0x%x-byte hole created", hole);
free(data);
free(prev_seg->data);
prev_seg->data = new_data;
prev_seg->length = new_length;
last_end = this_end;
phdr++;
continue;
}
}
PrintAndLogEx(WARNING, "Warning: segment does not begin on a block boundary, will pad");
memmove(data + block_offset, data, filesz);
memset(data, 0xFF, block_offset);
filesz += block_offset;
paddr -= block_offset;
}
seg->data = data;
seg->start = paddr;
seg->length = filesz;
seg++;
ctx->num_segs++;
last_end = paddr + filesz;
phdr++;
}
return 0;
}
// Sanity check segments and check for bootloader writes
static int check_segs(flash_file_t *ctx, int can_write_bl) {
for (int i = 0; i < ctx->num_segs; i++) {
flash_seg_t *seg = &ctx->segments[i];
if (seg->start & (BLOCK_SIZE - 1)) {
PrintAndLogEx(ERR, "Error: Segment is not aligned");
return -1;
}
if (seg->start < FLASH_START) {
PrintAndLogEx(ERR, "Error: Segment is outside of flash bounds");
return -1;
}
if (seg->start + seg->length > FLASH_END) {
PrintAndLogEx(ERR, "Error: Segment is outside of flash bounds");
return -1;
}
if (!can_write_bl && seg->start < BOOTLOADER_END) {
PrintAndLogEx(ERR, "Attempted to write bootloader but bootloader writes are not enabled");
return -1;
}
}
return 0;
}
// Load an ELF file and prepare it for flashing
int flash_load(flash_file_t *ctx, const char *name, int can_write_bl) {
FILE *fd;
Elf32_Ehdr ehdr;
Elf32_Phdr *phdrs = NULL;
uint16_t num_phdrs;
int res;
fd = fopen(name, "rb");
if (!fd) {
PrintAndLogEx(ERR, _RED_("Could not open file") "%s >>> ", name);
perror(NULL);
goto fail;
}
PrintAndLogEx(SUCCESS, _BLUE_("Loading ELF file") _YELLOW_("%s"), name);
if (fread(&ehdr, sizeof(ehdr), 1, fd) != 1) {
PrintAndLogEx(ERR, "Error while reading ELF file header");
goto fail;
}
if (memcmp(ehdr.e_ident, elf_ident, sizeof(elf_ident))
|| le32(ehdr.e_version) != 1) {
PrintAndLogEx(ERR, "Not an ELF file or wrong ELF type");
goto fail;
}
if (le16(ehdr.e_type) != ET_EXEC) {
PrintAndLogEx(ERR, "ELF is not executable");
goto fail;
}
if (le16(ehdr.e_machine) != EM_ARM) {
PrintAndLogEx(ERR, "Wrong ELF architecture");
goto fail;
}
if (!ehdr.e_phnum || !ehdr.e_phoff) {
PrintAndLogEx(ERR, "ELF has no PHDRs");
goto fail;
}
if (le16(ehdr.e_phentsize) != sizeof(Elf32_Phdr)) {
// could be a structure padding issue...
PrintAndLogEx(ERR, "Either the ELF file or this code is made of fail");
goto fail;
}
num_phdrs = le16(ehdr.e_phnum);
phdrs = calloc(le16(ehdr.e_phnum) * sizeof(Elf32_Phdr), sizeof(uint8_t));
if (!phdrs) {
PrintAndLogEx(ERR, "Out of memory");
goto fail;
}
if (fseek(fd, le32(ehdr.e_phoff), SEEK_SET) < 0) {
PrintAndLogEx(ERR, "Error while reading ELF PHDRs");
goto fail;
}
if (fread(phdrs, sizeof(Elf32_Phdr), num_phdrs, fd) != num_phdrs) {
PrintAndLogEx(ERR, "Error while reading ELF PHDRs");
goto fail;
}
res = build_segs_from_phdrs(ctx, fd, phdrs, num_phdrs);
if (res < 0)
goto fail;
res = check_segs(ctx, can_write_bl);
if (res < 0)
goto fail;
free(phdrs);
fclose(fd);
ctx->filename = name;
return 0;
fail:
if (phdrs)
free(phdrs);
if (fd)
fclose(fd);
flash_free(ctx);
return -1;
}
// Get the state of the proxmark, backwards compatible
static int get_proxmark_state(uint32_t *state) {
SendCommandBL(CMD_DEVICE_INFO, 0, 0, 0, NULL, 0);
PacketResponseNG resp;
WaitForResponse(CMD_UNKNOWN, &resp); // wait for any response. No timeout.
// Three outcomes:
// 1. The old bootrom code will ignore CMD_DEVICE_INFO, but respond with an ACK
// 2. The old os code will respond with CMD_DEBUG_PRINT_STRING and "unknown command"
// 3. The new bootrom and os codes will respond with CMD_DEVICE_INFO and flags
switch (resp.cmd) {
case CMD_ACK:
*state = DEVICE_INFO_FLAG_CURRENT_MODE_BOOTROM;
break;
case CMD_DEBUG_PRINT_STRING:
*state = DEVICE_INFO_FLAG_CURRENT_MODE_OS;
break;
case CMD_DEVICE_INFO:
*state = resp.oldarg[0];
break;
default:
PrintAndLogEx(ERR, _RED_("Error:") "Couldn't get Proxmark3 state, bad response type: 0x%04x", resp.cmd);
return -1;
break;
}
return 0;
}
// Enter the bootloader to be able to start flashing
static int enter_bootloader(char *serial_port_name) {
uint32_t state;
if (get_proxmark_state(&state) < 0)
return -1;
/* Already in flash state, we're done. */
if (state & DEVICE_INFO_FLAG_CURRENT_MODE_BOOTROM)
return 0;
if (state & DEVICE_INFO_FLAG_CURRENT_MODE_OS) {
PrintAndLogEx(SUCCESS, _BLUE_("Entering bootloader..."));
if ((state & DEVICE_INFO_FLAG_BOOTROM_PRESENT)
&& (state & DEVICE_INFO_FLAG_OSIMAGE_PRESENT)) {
// New style handover: Send CMD_START_FLASH, which will reset the board
// and enter the bootrom on the next boot.
SendCommandBL(CMD_START_FLASH, 0, 0, 0, NULL, 0);
PrintAndLogEx(SUCCESS, "(Press and release the button only to " _YELLOW_("abort") ")");
} else {
// Old style handover: Ask the user to press the button, then reset the board
SendCommandBL(CMD_HARDWARE_RESET, 0, 0, 0, NULL, 0);
PrintAndLogEx(SUCCESS, "Press and hold down button NOW if your bootloader requires it.");
}
msleep(100);
CloseProxmark();
// Let time to OS to make the port disappear
msleep(1000);
if (OpenProxmark(serial_port_name, true, 60, true, FLASHMODE_SPEED)) {
PrintAndLogEx(NORMAL, " " _GREEN_("Found"));
return 0;
} else {
PrintAndLogEx(ERR, _RED_("Error:") "Proxmark3 not found.");
return -1;
}
}
PrintAndLogEx(ERR, _RED_("Error:") "Unknown Proxmark3 mode");
return -1;
}
static int wait_for_ack(PacketResponseNG *ack) {
WaitForResponse(CMD_UNKNOWN, ack);
if (ack->cmd != CMD_ACK) {
PrintAndLogEx(ERR, "Error: Unexpected reply 0x%04x %s (expected ACK)",
ack->cmd,
(ack->cmd == CMD_NACK) ? "NACK" : ""
);
return -1;
}
return 0;
}
// Go into flashing mode
int flash_start_flashing(int enable_bl_writes, char *serial_port_name) {
uint32_t state;
if (enter_bootloader(serial_port_name) < 0)
return -1;
if (get_proxmark_state(&state) < 0)
return -1;
if (state & DEVICE_INFO_FLAG_UNDERSTANDS_START_FLASH) {
// This command is stupid. Why the heck does it care which area we're
// flashing, as long as it's not the bootloader area? The mind boggles.
PacketResponseNG resp;
if (enable_bl_writes) {
SendCommandBL(CMD_START_FLASH, FLASH_START, FLASH_END, START_FLASH_MAGIC, NULL, 0);
} else {
SendCommandBL(CMD_START_FLASH, BOOTLOADER_END, FLASH_END, 0, NULL, 0);
}
return wait_for_ack(&resp);
} else {
PrintAndLogEx(ERR, _RED_("Note: Your bootloader does not understand the new START_FLASH command"));
PrintAndLogEx(ERR, _RED_("It is recommended that you update your bootloader") "\n");
}
return 0;
}
static int write_block(uint32_t address, uint8_t *data, uint32_t length) {
uint8_t block_buf[BLOCK_SIZE];
memset(block_buf, 0xFF, BLOCK_SIZE);
memcpy(block_buf, data, length);
PacketResponseNG resp;
SendCommandBL(CMD_FINISH_WRITE, address, 0, 0, block_buf, length);
int ret = wait_for_ack(&resp);
if (ret && resp.oldarg[0]) {
uint32_t lock_bits = resp.oldarg[0] >> 16;
bool lock_error = resp.oldarg[0] & AT91C_MC_LOCKE;
bool prog_error = resp.oldarg[0] & AT91C_MC_PROGE;
bool security_bit = resp.oldarg[0] & AT91C_MC_SECURITY;
PrintAndLogEx(NORMAL, "%s", lock_error ? " Lock Error" : "");
PrintAndLogEx(NORMAL, "%s", prog_error ? " Invalid Command or bad Keyword" : "");
PrintAndLogEx(NORMAL, "%s", security_bit ? " Security Bit is set!" : "");
PrintAndLogEx(NORMAL, " Lock Bits: 0x%04x", lock_bits);
}
return ret;
}
// Write a file's segments to Flash
int flash_write(flash_file_t *ctx) {
PrintAndLogEx(SUCCESS, "Writing segments for file: %s", ctx->filename);
for (int i = 0; i < ctx->num_segs; i++) {
flash_seg_t *seg = &ctx->segments[i];
uint32_t length = seg->length;
uint32_t blocks = (length + BLOCK_SIZE - 1) / BLOCK_SIZE;
uint32_t end = seg->start + length;
PrintAndLogEx(SUCCESS, " 0x%08x..0x%08x [0x%x / %u blocks]", seg->start, end - 1, length, blocks);
fflush(stdout);
int block = 0;
uint8_t *data = seg->data;
uint32_t baddr = seg->start;
while (length) {
uint32_t block_size = length;
if (block_size > BLOCK_SIZE)
block_size = BLOCK_SIZE;
if (write_block(baddr, data, block_size) < 0) {
PrintAndLogEx(ERR, "Error writing block %d of %u", block, blocks);
return -1;
}
data += block_size;
baddr += block_size;
length -= block_size;
block++;
fprintf(stdout, ".");
fflush(stdout);
}
PrintAndLogEx(NORMAL, " " _GREEN_("OK"));
fflush(stdout);
}
return 0;
}
// free a file context
void flash_free(flash_file_t *ctx) {
if (!ctx)
return;
if (ctx->segments) {
for (int i = 0; i < ctx->num_segs; i++)
free(ctx->segments[i].data);
free(ctx->segments);
ctx->segments = NULL;
ctx->num_segs = 0;
}
}
// just reset the unit
int flash_stop_flashing(void) {
SendCommandBL(CMD_HARDWARE_RESET, 0, 0, 0, NULL, 0);
msleep(100);
return 0;
}