X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/815f3f255960c429f62435cc7506ff597385b2cf..refs/pull/304/head:/client/flash.c?ds=sidebyside

diff --git a/client/flash.c b/client/flash.c
index b01bb154..0b940e99 100644
--- a/client/flash.c
+++ b/client/flash.c
@@ -1,296 +1,477 @@
-#ifdef WIN32
-#include <windows.h>
-#include <setupapi.h>
-#include <ctype.h>
-#define bzero(b,len) (memset((b), '\0', (len)), (void) 0)
-BOOL UsbConnect(void);
-#else
-#include <usb.h>
-#endif
+//-----------------------------------------------------------------------------
+// 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 <stdio.h>
-#include <unistd.h>
-#include <stdlib.h>
-#include <stdint.h>
-#include <stdbool.h>
-#include <strings.h>
 #include <string.h>
-#include <errno.h>
-#include <ctype.h>
-
-#include "prox.h"
-#ifndef WIN32
+#include <stdlib.h>
+#include <inttypes.h>
+#include <unistd.h>
 #include "proxmark3.h"
-#endif
+#include "util.h"
 #include "flash.h"
 #include "elf.h"
+#include "proxendian.h"
+#include "usb_cmd.h"
 
-static uint32_t ExpectedAddr;
-static uint8_t QueuedToSend[256];
-static bool AllWritten;
-#define PHYSICAL_FLASH_START 0x100000
-#define PHYSICAL_FLASH_END   0x200000
+void SendCommand(UsbCommand* txcmd);
+void ReceiveCommand(UsbCommand* rxcmd);
+void CloseProxmark();
+int OpenProxmark(size_t i);
 
-void WaitForAck(void) {
-	UsbCommand ack;
-	ReceiveCommand(&ack);
-	if(ack.cmd != CMD_ACK) {
-		printf("bad ACK\n");
-		exit(-1);
-	}
-}
+// FIXME: what the fuckity fuck
+unsigned int current_command = CMD_UNKNOWN;
+
+#define FLASH_START            0x100000
+#define FLASH_SIZE             (256*1024)
+#define FLASH_END              (FLASH_START + FLASH_SIZE)
+#define BOOTLOADER_SIZE        0x2000
+#define BOOTLOADER_END         (FLASH_START + BOOTLOADER_SIZE)
+
+#define BLOCK_SIZE             0x200
 
-struct partition partitions[] = {
-		{0x100000, 0x102000, 1, "bootrom"},
-		{0x102000, 0x110000, 0, "fpga"},
-		{0x110000, 0x140000, 0, "os"},
-		{0, 0, 0, NULL},
+static const uint8_t elf_ident[] = {
+	0x7f, 'E', 'L', 'F',
+	ELFCLASS32,
+	ELFDATA2LSB,
+	EV_CURRENT
 };
 
-void WriteBlock(unsigned int block_start, unsigned int len, unsigned char *buf)
+// 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, int num_phdrs)
 {
-	unsigned char temp_buf[256];
-	if (block_start & 0xFF) {
-		printf("moving stuff forward by %d bytes\n", block_start & 0xFF);
-		memset(temp_buf, 0xFF, block_start & 0xFF);
-		memcpy(temp_buf + (block_start & 0xFF), buf, len);
-		block_start &= ~0xFF;
-	} else memcpy(temp_buf, buf, len);
-	
-	UsbCommand c = {CMD_SETUP_WRITE};
-
-	int i;
-	for(i = 0; i < 240; i += 48) {
-		memcpy(c.d.asBytes, temp_buf+i, 48);
-		c.arg[0] = (i/4);
-		SendCommand(&c);
-		WaitForAck();
-	}
+	Elf32_Phdr *phdr = phdrs;
+	flash_seg_t *seg;
+	uint32_t last_end = 0;
 
-	c.cmd = CMD_FINISH_WRITE;
-	c.arg[0] = block_start;
+	ctx->segments = malloc(sizeof(flash_seg_t) * num_phdrs);
+	if (!ctx->segments) {
+		fprintf(stderr, "Out of memory\n");
+		return -1;
+	}
+	ctx->num_segs = 0;
+	seg = ctx->segments;
 
-//	printf("writing block %08x\r", c.arg[0]);
-	memcpy(c.d.asBytes, temp_buf+240, 16);
-	SendCommand(&c);
-	WaitForAck();
+	fprintf(stderr, "Loading usable ELF segments:\n");
+	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;
+		}
+		fprintf(stderr, "%d: V 0x%08x P 0x%08x (0x%08x->0x%08x) [%c%c%c] @0x%x\n",
+		        i, vaddr, paddr, filesz, memsz,
+		        flags & PF_R ? 'R' : ' ',
+		        flags & PF_W ? 'W' : ' ',
+		        flags & PF_X ? 'X' : ' ',
+		        offset);
+		if (filesz != memsz) {
+			fprintf(stderr, "Error: PHDR file size does not equal memory size\n"
+			                "(DATA+BSS PHDRs do not make sense on ROM platforms!)\n");
+			return -1;
+		}
+		if (paddr < last_end) {
+			fprintf(stderr, "Error: PHDRs not sorted or overlap\n");
+			return -1;
+		}
+		if (paddr < FLASH_START || (paddr+filesz) > FLASH_END) {
+			fprintf(stderr, "Error: PHDR is not contained in Flash\n");
+			return -1;
+		}
+		if (vaddr >= FLASH_START && vaddr < FLASH_END && (flags & PF_W)) {
+			fprintf(stderr, "Error: Flash VMA segment is writable\n");
+			return -1;
+		}
 
-	AllWritten = true;
-}
+		uint8_t *data;
+		// make extra space if we need to move the data forward
+		data = malloc(filesz + BLOCK_SIZE);
+		if (!data) {
+			fprintf(stderr, "Out of memory\n");
+			return -1;
+		}
+		if (fseek(fd, offset, SEEK_SET) < 0 || fread(data, 1, filesz, fd) != filesz) {
+			fprintf(stderr, "Error while reading PHDR payload\n");
+			free(data);
+			return -1;
+		}
 
-void LoadFlashFromFile(const char *file, int start_addr, int end_addr)
-{
-	FILE *f = fopen(file, "rb");
-	if(!f) {
-		printf("couldn't open file\n");
-		exit(-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);
 
-	char buf[4];
-	fread(buf, 1, 4, f);
-	if (memcmp(buf, "\x7F" "ELF", 4) == 0) {
-		int i;
-		fseek(f, 0, SEEK_SET);
-		Elf32_Ehdr header;
-		fread(&header, 1, sizeof(header), f);
-		int count = header.e_phnum;
-		printf("count=%d phoff=%x\n", count, header.e_phoff);
-		Elf32_Phdr phdr;
-		
-		for (i=0; i<header.e_phnum; i++) {
-			fseek(f, header.e_phoff + i * sizeof(Elf32_Phdr), SEEK_SET);
-			fread(&phdr, 1, sizeof(phdr), f);
-			printf("type=%d offset=%x paddr=%x vaddr=%x filesize=%x memsize=%x flags=%x align=%x\n",
-				phdr.p_type, phdr.p_offset, phdr.p_paddr, phdr.p_vaddr, phdr.p_filesz, phdr.p_memsz, phdr.p_flags, phdr.p_align);
-			if (phdr.p_type == PT_LOAD && phdr.p_filesz > 0 && phdr.p_paddr >= PHYSICAL_FLASH_START
-				&& (phdr.p_paddr + phdr.p_filesz) < PHYSICAL_FLASH_END) {
-				printf("flashing offset=%x paddr=%x size=%x\n", phdr.p_offset, phdr.p_paddr, phdr.p_filesz);
-				if (phdr.p_offset == 0) {
-					printf("skipping forward 0x2000 because of strange linker thing\n");
-					phdr.p_offset += 0x2000;
-					phdr.p_paddr += 0x2000;
-					phdr.p_filesz -= 0x2000;
-					phdr.p_memsz -= 0x2000;
+				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 = malloc(new_length);
+					if (!new_data) {
+						fprintf(stderr, "Out of memory\n");
+						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);
+					fprintf(stderr, "Note: Extending previous segment from 0x%x to 0x%x bytes\n",
+					        prev_seg->length, new_length);
+					if (hole)
+						fprintf(stderr, "Note: 0x%x-byte hole created\n", hole);
+					free(data);
+					free(prev_seg->data);
+					prev_seg->data = new_data;
+					prev_seg->length = new_length;
+					last_end = this_end;
+					phdr++;
+					continue;
 				}
+			}
+			fprintf(stderr, "Warning: segment does not begin on a block boundary, will pad\n");
+			memmove(data + block_offset, data, filesz);
+			memset(data, 0xFF, block_offset);
+			filesz += block_offset;
+			paddr -= block_offset;
+		}
 
-				fseek(f, phdr.p_offset, SEEK_SET);
-				ExpectedAddr = phdr.p_paddr;
-				while (ExpectedAddr < (phdr.p_paddr + phdr.p_filesz)) {
-					unsigned int bytes_to_read = phdr.p_paddr + phdr.p_filesz - ExpectedAddr;
-					if (bytes_to_read > 256)
-						bytes_to_read=256;
-					else
-						memset(QueuedToSend, 0xFF, 256);
-					fread(QueuedToSend, 1, bytes_to_read, f);
-					printf("WriteBlock(%x, %d, %02x %02x %02x %02x %02x %02x %02x %02x ... %02x %02x %02x %02x %02x %02x %02x %02x)\n", ExpectedAddr, bytes_to_read,
-							QueuedToSend[0], QueuedToSend[1], QueuedToSend[2], QueuedToSend[3],
-							QueuedToSend[4], QueuedToSend[5], QueuedToSend[6], QueuedToSend[7],
-							QueuedToSend[248], QueuedToSend[249], QueuedToSend[250], QueuedToSend[251],
-							QueuedToSend[252], QueuedToSend[253], QueuedToSend[254], QueuedToSend[255]);
-					WriteBlock(ExpectedAddr, 256, QueuedToSend);
-					ExpectedAddr += bytes_to_read;
-				}
-            }
-        }
+		seg->data = data;
+		seg->start = paddr;
+		seg->length = filesz;
+		seg++;
+		ctx->num_segs++;
 
-		fclose(f);
-		printf("\ndone.\n");
-		return;
-	} else printf("Bad file format\n");		
+		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)) {
+			fprintf(stderr, "Error: Segment is not aligned\n");
+			return -1;
+		}
+		if (seg->start < FLASH_START) {
+			fprintf(stderr, "Error: Segment is outside of flash bounds\n");
+			return -1;
+		}
+		if (seg->start + seg->length > FLASH_END) {
+			fprintf(stderr, "Error: Segment is outside of flash bounds\n");
+			return -1;
+		}
+		if (!can_write_bl && seg->start < BOOTLOADER_END) {
+			fprintf(stderr, "Attempted to write bootloader but bootloader writes are not enabled\n");
+			return -1;
+		}
+	}
+	return 0;
 }
 
-int PrepareFlash(struct partition *p, const char *filename, unsigned int state)
+// Load an ELF file and prepare it for flashing
+int flash_load(flash_file_t *ctx, const char *name, int can_write_bl)
 {
-	if(state & DEVICE_INFO_FLAG_UNDERSTANDS_START_FLASH) {
-		UsbCommand c = {CMD_START_FLASH, {p->start, p->end, 0}};
-		
-		/* Only send magic when flashing bootrom */
-		if(p->precious)
-			c.arg[2] = START_FLASH_MAGIC;
-		else
-			c.arg[2] = 0;
+	FILE *fd = NULL;
+	Elf32_Ehdr ehdr;
+	Elf32_Phdr *phdrs = NULL;
+	int num_phdrs;
+	int res;
 
-		SendCommand(&c);
-		WaitForAck();
-	} else {
-		fprintf(stderr, "Warning: Your bootloader does not understand the new START_FLASH command\n");
-		fprintf(stderr, "         It is recommended that you update your bootloader\n\n");
-		exit(0);
+	fd = fopen(name, "rb");
+	if (!fd) {
+		fprintf(stderr, "Could not open file '%s': ", name);
+		perror(NULL);
+		goto fail;
+	}
+
+	fprintf(stderr, "Loading ELF file '%s'...\n", name);
+
+	if (fread(&ehdr, sizeof(ehdr), 1, fd) != 1) {
+		fprintf(stderr, "Error while reading ELF file header\n");
+		goto fail;
 	}
-	
-	LoadFlashFromFile(filename, p->start, p->end);
-	return 1;
+	if (memcmp(ehdr.e_ident, elf_ident, sizeof(elf_ident))
+		|| le32(ehdr.e_version) != 1)
+	{
+		fprintf(stderr, "Not an ELF file or wrong ELF type\n");
+		goto fail;
+	}
+	if (le16(ehdr.e_type) != ET_EXEC) {
+		fprintf(stderr, "ELF is not executable\n");
+		goto fail;
+	}
+	if (le16(ehdr.e_machine) != EM_ARM) {
+		fprintf(stderr, "Wrong ELF architecture\n");
+		goto fail;
+	}
+	if (!ehdr.e_phnum || !ehdr.e_phoff) {
+		fprintf(stderr, "ELF has no PHDRs\n");
+		goto fail;
+	}
+	if (le16(ehdr.e_phentsize) != sizeof(Elf32_Phdr)) {
+		// could be a structure padding issue...
+		fprintf(stderr, "Either the ELF file or this code is made of fail\n");
+		goto fail;
+	}
+	num_phdrs = le16(ehdr.e_phnum);
+
+	phdrs = malloc(le16(ehdr.e_phnum) * sizeof(Elf32_Phdr));
+	if (!phdrs) {
+		fprintf(stderr, "Out of memory\n");
+		goto fail;
+	}
+	if (fseek(fd, le32(ehdr.e_phoff), SEEK_SET) < 0) {
+		fprintf(stderr, "Error while reading ELF PHDRs\n");
+		goto fail;
+	}
+	if (fread(phdrs, sizeof(Elf32_Phdr), num_phdrs, fd) != num_phdrs) {
+		fprintf(stderr, "Error while reading ELF PHDRs\n");
+		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;
 }
 
-unsigned int GetProxmarkState(void)
+// Get the state of the proxmark, backwards compatible
+static int get_proxmark_state(uint32_t *state)
 {
-	unsigned int state = 0;
-	
 	UsbCommand c;
 	c.cmd = CMD_DEVICE_INFO;
-	SendCommand(&c);
-	
+  SendCommand(&c);
 	UsbCommand resp;
 	ReceiveCommand(&resp);
-	/* Three cases: 
-	 * 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.arg[0];
-		break;
-	default:
-		fprintf(stderr, "Couldn't get proxmark state, bad response type: 0x%04X\n", resp.cmd);
-		exit(-1);
-		break;
+
+	// 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.arg[0];
+			break;
+		default:
+			fprintf(stderr, "Error: Couldn't get proxmark state, bad response type: 0x%04" PRIx64 "\n", resp.cmd);
+			return -1;
+			break;
 	}
-	
-	return state;
+
+	return 0;
 }
 
-unsigned int EnterFlashState(void)
+// Enter the bootloader to be able to start flashing
+static int enter_bootloader(char *serial_port_name)
 {
-	unsigned int state = GetProxmarkState();
-	
-	if(state & DEVICE_INFO_FLAG_CURRENT_MODE_BOOTROM) {
+	uint32_t state;
+
+	if (get_proxmark_state(&state) < 0)
+		return -1;
+
+	if (state & DEVICE_INFO_FLAG_CURRENT_MODE_BOOTROM) {
 		/* Already in flash state, we're done. */
-		return state;
+		return 0;
 	}
-	
-	if(state & DEVICE_INFO_FLAG_CURRENT_MODE_OS) {
-		fprintf(stderr,"Entering flash-mode...\n");
+
+	if (state & DEVICE_INFO_FLAG_CURRENT_MODE_OS) {
+		fprintf(stderr,"Entering bootloader...\n");
 		UsbCommand c;
-		bzero(&c, sizeof(c));
-		
-		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.
-			 */
+		memset(&c, 0, sizeof (c));
+
+		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.
 			c.cmd = CMD_START_FLASH;
 			SendCommand(&c);
-			fprintf(stderr,"(You don't have to do anything. Press and release the button only if you want to abort)\n");
-			fprintf(stderr,"Waiting for Proxmark to reappear on USB... ");
+			fprintf(stderr,"(Press and release the button only to abort)\n");
 		} else {
-			/* Old style handover: Ask the user to press the button, then reset the board */
+			// Old style handover: Ask the user to press the button, then reset the board
 			c.cmd = CMD_HARDWARE_RESET;
 			SendCommand(&c);
-			fprintf(stderr,"(Press and hold down button NOW if your bootloader requires it)\n");
-			fprintf(stderr,"Waiting for Proxmark to reappear on USB... ");
+			fprintf(stderr,"Press and hold down button NOW if your bootloader requires it.\n");
 		}
-
-#ifdef WIN32
-		Sleep(1000);
-		while(!UsbConnect()) { Sleep(1000); }
-#else
+    msleep(100);
 		CloseProxmark();
-		sleep(1);
 
-		while(!(devh=OpenProxmark(0))) { sleep(1); }
-#endif
-		fprintf(stderr,"Found.\n");
+		fprintf(stderr,"Waiting for Proxmark to reappear on %s",serial_port_name);
+    do {
+			sleep(1);
+			fprintf(stderr, ".");
+		} while (!OpenProxmark(0));
+		fprintf(stderr," Found.\n");
 
-		return GetProxmarkState();
+		return 0;
+	}
+
+	fprintf(stderr, "Error: Unknown Proxmark mode\n");
+	return -1;
+}
+
+static int wait_for_ack(void)
+{
+  UsbCommand ack;
+	ReceiveCommand(&ack);
+	if (ack.cmd != CMD_ACK) {
+		printf("Error: Unexpected reply 0x%04" PRIx64 " (expected ACK)\n", ack.cmd);
+		return -1;
 	}
-	
 	return 0;
 }
 
-/* On first call, have *offset = -1, *length = 0; */
-int find_next_area(const char *str, int *offset, int *length)
+// Go into flashing mode
+int flash_start_flashing(int enable_bl_writes,char *serial_port_name)
 {
-	if(*str == '\0') return 0;
-	if((*offset >= 0) && str[*offset + *length] == '\0') return 0;
-	*offset += 1 + *length;
-	
-	char *next_comma = strchr(str + *offset, ',');
-	if(next_comma == NULL) {
-		*length = strlen(str) - *offset;
+	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.
+		UsbCommand c = {CMD_START_FLASH};
+
+		if (enable_bl_writes) {
+			c.arg[0] = FLASH_START;
+			c.arg[1] = FLASH_END;
+			c.arg[2] = START_FLASH_MAGIC;
+		} else {
+			c.arg[0] = BOOTLOADER_END;
+			c.arg[1] = FLASH_END;
+			c.arg[2] = 0;
+		}
+		SendCommand(&c);
+		return wait_for_ack();
 	} else {
-		*length = next_comma-(str+*offset);
+		fprintf(stderr, "Note: Your bootloader does not understand the new START_FLASH command\n");
+		fprintf(stderr, "      It is recommended that you update your bootloader\n\n");
 	}
-	return 1;
+
+	return 0;
 }
 
-void do_flash(char **argv) {
-	unsigned int state = EnterFlashState();
+static int write_block(uint32_t address, uint8_t *data, uint32_t length)
+{
+	uint8_t block_buf[BLOCK_SIZE];
 
-	if (!(state & DEVICE_INFO_FLAG_CURRENT_MODE_BOOTROM)) {
-		fprintf(stderr, "Proxmark would not enter flash state, abort\n");
-		exit(-1);
-	}
+	memset(block_buf, 0xFF, BLOCK_SIZE);
+	memcpy(block_buf, data, length);
+  UsbCommand c;
+	c.cmd = CMD_FINISH_WRITE;
+	c.arg[0] = address;
+	memcpy(c.d.asBytes, block_buf, length);
+  SendCommand(&c);
+  return wait_for_ack();
+}
+
+// Write a file's segments to Flash
+int flash_write(flash_file_t *ctx)
+{
+	fprintf(stderr, "Writing segments for file: %s\n", 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;
 
-	int offset=-1, length=0;
-	int current_area = 0;
-	while(find_next_area(argv[1], &offset, &length)) {
-		int i;
-		struct partition *p = NULL;
-		for (i=0; i<sizeof(partitions)/sizeof(partitions[0]); i++) {
-			if (strncmp(partitions[i].name, argv[1] + offset, length) == 0) {
-				/* Check if the name matches the bootrom partition, and if so, require "bootrom" to
-			 	* be written in full. The other names may be abbreviated.
-			 	*/
-				if(!partitions[i].precious || (strlen(partitions[i].name) == length))
-					p = &partitions[i];
-				break;
+		fprintf(stderr, " 0x%08x..0x%08x [0x%x / %d blocks]",
+		        seg->start, end - 1, length, blocks);
+
+		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) {
+				fprintf(stderr, " ERROR\n");
+				fprintf(stderr, "Error writing block %d of %d\n", block, blocks);
+				return -1;
 			}
-		}
 
-		if(p == NULL) {
-			fprintf(stderr, "Warning: area name '");
-			fwrite(argv[1]+offset, length, 1, stderr);
-			fprintf(stderr, "' unknown, ignored\n");
-		} else {
-			fprintf(stderr, "Flashing %s from %s\n", p->name, argv[2+current_area]);
-			PrepareFlash(p, argv[2+current_area], state);
+			data += block_size;
+			baddr += block_size;
+			length -= block_size;
+			block++;
+			fprintf(stderr, ".");
 		}
-		current_area++;
+		fprintf(stderr, " OK\n");
 	}
+	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) {
+	UsbCommand c = {CMD_HARDWARE_RESET};
+  SendCommand(&c);
+  msleep(100);
+  return 0;
 }