diff options
Diffstat (limited to 'tools/firmware-utils')
-rw-r--r-- | tools/firmware-utils/Makefile | 1 | ||||
-rw-r--r-- | tools/firmware-utils/src/mkrasimage.c | 459 |
2 files changed, 460 insertions, 0 deletions
diff --git a/tools/firmware-utils/Makefile b/tools/firmware-utils/Makefile index 436a43794c..00917c3417 100644 --- a/tools/firmware-utils/Makefile +++ b/tools/firmware-utils/Makefile @@ -70,6 +70,7 @@ define Host/Compile $(call cc,fix-u-media-header cyg_crc32,-Wall) $(call cc,hcsmakeimage bcmalgo) $(call cc,mkporayfw, -Wall) + $(call cc,mkrasimage, --std=gnu99) $(call cc,mkhilinkfw, -lcrypto) $(call cc,mkdcs932, -Wall) $(call cc,mkheader_gemtek,-lz) diff --git a/tools/firmware-utils/src/mkrasimage.c b/tools/firmware-utils/src/mkrasimage.c new file mode 100644 index 0000000000..8eee29cc08 --- /dev/null +++ b/tools/firmware-utils/src/mkrasimage.c @@ -0,0 +1,459 @@ +/* + * --- ZyXEL header format --- + * Original Version by Benjamin Berg <benjamin@sipsolutions.net> + * C implementation based on generation-script by Christian Lamparter <chunkeey@gmail.com> + * + * The firmware image prefixed with a header (which is written into the MTD device). + * The header is one erase block (~64KiB) in size, but the checksum only convers the + * first 2KiB. Padding is 0xff. All integers are in big-endian. + * + * The checksum is always a 16-Bit System V checksum (sum -s) stored in a 32-Bit integer. + * + * 4 bytes: checksum of the rootfs image + * 4 bytes: length of the contained rootfs image file (big endian) + * 32 bytes: Firmware Version string (NUL terminated, 0xff padded) + * 4 bytes: checksum over the header partition (big endian - see below) + * 64 bytes: Model (e.g. "NBG6617", NUL termiated, 0xff padded) + * 4 bytes: checksum of the kernel partition + * 4 bytes: length of the contained kernel image file (big endian) + * rest: 0xff padding (To erase block size) + * + * The kernel partition checksum and length is not used for every device. + * If it's notused, pad those 8 bytes with 0xFF. + * + * The checksums are calculated by adding up all bytes and if a 16bit + * overflow occurs, one is added and the sum is masked to 16 bit: + * csum = csum + databyte; if (csum > 0xffff) { csum += 1; csum &= 0xffff }; + * Should the file have an odd number of bytes then the byte len-0x800 is + * used additionally. + * + * The checksum for the header is calculated over the first 2048 bytes with + * the rootfs image checksum as the placeholder during calculation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + * + */ +#include <fcntl.h> +#include <getopt.h> +#include <libgen.h> +#include <stdio.h> +#include <string.h> +#include <stdlib.h> +#include <unistd.h> + +#include <sys/mman.h> +#include <sys/stat.h> + +#include <arpa/inet.h> + +#define VERSION_STRING_LEN 31 +#define ROOTFS_HEADER_LEN 40 + +#define KERNEL_HEADER_LEN 8 + +#define BOARD_NAME_LEN 64 +#define BOARD_HEADER_LEN 68 + +#define HEADER_PARTITION_CALC_LENGTH 2048 +#define HEADER_PARTITION_LENGTH 0x10000 + +struct file_info { + char *name; /* name of the file */ + char *data; /* file content */ + size_t size; /* length of the file */ +}; + +static char *progname; + +static char *board_name = 0; +static char *version_name = 0; +static unsigned int rootfs_size = 0; + +static struct file_info kernel = { NULL, NULL, 0 }; +static struct file_info rootfs = { NULL, NULL, 0 }; +static struct file_info rootfs_out = { NULL, NULL, 0 }; +static struct file_info out = { NULL, NULL, 0 }; + +#define ERR(fmt, ...) do { \ + fprintf(stderr, "[%s] *** error: " fmt "\n", \ + progname, ## __VA_ARGS__ ); \ +} while (0) + +void map_file(struct file_info *finfo) +{ + struct stat file_stat = {0}; + int fd; + + fd = open(finfo->name, O_RDONLY, (mode_t)0600); + if (fd == -1) { + ERR("Error while opening file %s.", finfo->name); + exit(EXIT_FAILURE); + } + + if (fstat(fd, &file_stat) == -1) { + ERR("Error getting file size for %s.", finfo->name); + exit(EXIT_FAILURE); + } + + finfo->size = file_stat.st_size; + finfo->data = mmap(0, finfo->size, PROT_READ, MAP_SHARED, fd, 0); + + if (finfo->data == MAP_FAILED) { + ERR("Error mapping file %s.", finfo->name); + exit(EXIT_FAILURE); + } + + close(fd); +} + +void unmap_file(struct file_info *finfo) +{ + if(munmap(finfo->data, finfo->size) == -1) { + ERR("Error unmapping file %s.", finfo->name); + exit(EXIT_FAILURE); + } +} + +void write_file(struct file_info *finfo) +{ + FILE *fout = fopen(finfo->name, "w"); + + fwrite(finfo->data, finfo->size, 1, fout); + + if (ferror(fout)) { + ERR("Wanted to write, but something went wrong."); + exit(EXIT_FAILURE); + } + + fclose(fout); +} + +void usage(int status) +{ + FILE *stream = (status != EXIT_SUCCESS) ? stderr : stdout; + + fprintf(stream, "Usage: %s [OPTIONS...]\n", progname); + fprintf(stream, + "\n" + "Options:\n" + " -k <kernel> path for kernel image\n" + " -r <rootfs> path for rootfs image\n" + " -s <rfssize> size of output rootfs\n" + " -v <version> version string\n" + " -b <boardname> name of board to generate image for\n" + " -o <out_name> name of output image\n" + " -h show this screen\n" + ); + + exit(status); +} + +static int sysv_chksm(const unsigned char *data, int size) +{ + int r; + int checksum; + unsigned int s = 0; /* The sum of all the input bytes, modulo (UINT_MAX + 1). */ + + + for (int i = 0; i < size; i++) { + s += data[i]; + } + + r = (s & 0xffff) + ((s & 0xffffffff) >> 16); + checksum = (r & 0xffff) + (r >> 16); + + return checksum; +} + +static int zyxel_chksm(const unsigned char *data, int size) +{ + return htonl(sysv_chksm(data, size)); +} + +char *generate_rootfs_header(struct file_info filesystem, char *version) +{ + size_t version_string_length; + unsigned int chksm, size; + char *rootfs_header; + size_t ptr = 0; + + rootfs_header = malloc(ROOTFS_HEADER_LEN); + if (!rootfs_header) { + ERR("Couldn't allocate memory for rootfs header!"); + exit(EXIT_FAILURE); + } + + /* Prepare padding for firmware-version string here */ + memset(rootfs_header, 0xff, ROOTFS_HEADER_LEN); + + chksm = zyxel_chksm((const unsigned char *)filesystem.data, filesystem.size); + size = htonl(filesystem.size); + + /* 4 bytes: checksum of the rootfs image */ + memcpy(rootfs_header + ptr, &chksm, 4); + ptr += 4; + + /* 4 bytes: length of the contained rootfs image file (big endian) */ + memcpy(rootfs_header + ptr, &size, 4); + ptr += 4; + + /* 32 bytes: Firmware Version string (NUL terminated, 0xff padded) */ + version_string_length = strlen(version) <= VERSION_STRING_LEN ? strlen(version) : VERSION_STRING_LEN; + memcpy(rootfs_header + ptr, version, version_string_length); + ptr += version_string_length; + /* Add null-terminator */ + rootfs_header[ptr] = 0x0; + + return rootfs_header; +} + +char *generate_kernel_header(struct file_info kernel) +{ + unsigned int chksm, size; + char *kernel_header; + size_t ptr = 0; + + kernel_header = malloc(KERNEL_HEADER_LEN); + if (!kernel_header) { + ERR("Couldn't allocate memory for kernel header!"); + exit(EXIT_FAILURE); + } + + chksm = zyxel_chksm((const unsigned char *)kernel.data, kernel.size); + size = htonl(kernel.size); + + /* 4 bytes: checksum of the kernel image */ + memcpy(kernel_header + ptr, &chksm, 4); + ptr += 4; + + /* 4 bytes: length of the contained kernel image file (big endian) */ + memcpy(kernel_header + ptr, &size, 4); + + return kernel_header; +} + +unsigned int generate_board_header_checksum(char *kernel_hdr, char *rootfs_hdr, char *boardname) +{ + char *board_hdr_tmp; + unsigned int sum; + size_t ptr = 0; + + /* + * The checksum of the board header is calculated over the first 2048 bytes of + * the header partition with the rootfs checksum used as a placeholder for then + * board checksum we calculate in this step. The checksum gained from this step + * is then used for the final board header partition. + */ + + board_hdr_tmp = malloc(HEADER_PARTITION_CALC_LENGTH); + if (!board_hdr_tmp) { + ERR("Couldn't allocate memory for temporary board header!"); + exit(EXIT_FAILURE); + } + memset(board_hdr_tmp, 0xff, HEADER_PARTITION_CALC_LENGTH); + + /* 40 bytes: RootFS header */ + memcpy(board_hdr_tmp, rootfs_hdr, ROOTFS_HEADER_LEN); + ptr += ROOTFS_HEADER_LEN; + + /* 4 bytes: RootFS checksum (BE) as placeholder for board-header checksum */ + memcpy(board_hdr_tmp + ptr, rootfs_hdr, 4); + ptr += 4; + + /* 32 bytes: Model (e.g. "NBG6617", NUL termiated, 0xff padded) */ + memcpy(board_hdr_tmp + ptr, boardname, strlen(boardname)); + ptr += strlen(boardname); + /* Add null-terminator */ + board_hdr_tmp[ptr] = 0x0; + ptr = ROOTFS_HEADER_LEN + 4 + BOARD_NAME_LEN; + + /* 8 bytes: Kernel header */ + if (kernel_hdr) + memcpy(board_hdr_tmp + ptr, kernel_hdr, 8); + + /* Calculate the checksum over the first 2048 bytes */ + sum = zyxel_chksm((const unsigned char *)board_hdr_tmp, HEADER_PARTITION_CALC_LENGTH); + free(board_hdr_tmp); + return sum; +} + +char *generate_board_header(char *kernel_hdr, char *rootfs_hdr, char *boardname) +{ + unsigned int board_checksum; + char *board_hdr; + + board_hdr = malloc(BOARD_HEADER_LEN); + if (!board_hdr) { + ERR("Couldn't allocate memory for board header!"); + exit(EXIT_FAILURE); + } + memset(board_hdr, 0xff, BOARD_HEADER_LEN); + + /* 4 bytes: checksum over the header partition (big endian) */ + board_checksum = generate_board_header_checksum(kernel_hdr, rootfs_hdr, boardname); + memcpy(board_hdr, &board_checksum, 4); + + /* 32 bytes: Model (e.g. "NBG6617", NUL termiated, 0xff padded) */ + memcpy(board_hdr + 4, boardname, strlen(boardname)); + board_hdr[4 + strlen(boardname)] = 0x0; + + return board_hdr; +} + +int build_image() +{ + char *rootfs_header = NULL; + char *kernel_header = NULL; + char *board_header = NULL; + + size_t ptr; + + /* Load files */ + if (kernel.name) + map_file(&kernel); + map_file(&rootfs); + + /* + * Allocate memory and copy input rootfs for temporary output rootfs. + * This is important as we have to generate the rootfs checksum over the + * entire rootfs partition. As we might have to pad the partition to allow + * for flashing via ZyXEL's Web-GUI, we prepare the rootfs partition for the + * output image here (and also use it for calculating the rootfs checksum). + * + * The roofs padding has to be done with 0x00. + */ + rootfs_out.data = calloc(rootfs_out.size, sizeof(char)); + memcpy(rootfs_out.data, rootfs.data, rootfs.size); + + /* Prepare headers */ + rootfs_header = generate_rootfs_header(rootfs_out, version_name); + if (kernel.name) + kernel_header = generate_kernel_header(kernel); + board_header = generate_board_header(kernel_header, rootfs_header, board_name); + + /* Prepare output file */ + out.size = HEADER_PARTITION_LENGTH + rootfs_out.size; + if (kernel.name) + out.size += kernel.size; + out.data = malloc(out.size); + memset(out.data, 0xFF, out.size); + + /* Build output image */ + memcpy(out.data, rootfs_header, ROOTFS_HEADER_LEN); + memcpy(out.data + ROOTFS_HEADER_LEN, board_header, BOARD_HEADER_LEN); + if (kernel.name) + memcpy(out.data + ROOTFS_HEADER_LEN + BOARD_HEADER_LEN, kernel_header, KERNEL_HEADER_LEN); + ptr = HEADER_PARTITION_LENGTH; + memcpy(out.data + ptr, rootfs_out.data, rootfs_out.size); + ptr += rootfs_out.size; + if (kernel.name) + memcpy(out.data + ptr, kernel.data, kernel.size); + + /* Write back output image */ + write_file(&out); + + /* Free allocated memory */ + if (kernel.name) + unmap_file(&kernel); + unmap_file(&rootfs); + free(out.data); + free(rootfs_out.data); + + free(rootfs_header); + if (kernel.name) + free(kernel_header); + free(board_header); + + return 0; +} + +int check_options() +{ + if (!rootfs.name) { + ERR("No rootfs filename supplied"); + return -2; + } + + if (!out.name) { + ERR("No output filename supplied"); + return -3; + } + + if (!board_name) { + ERR("No board-name supplied"); + return -4; + } + + if (!version_name) { + ERR("No version supplied"); + return -5; + } + + if (rootfs_size <= 0) { + ERR("Invalid rootfs size supplied"); + return -6; + } + + if (strlen(board_name) > 31) { + ERR("Board name is to long"); + return -7; + } + return 0; +} + +int main(int argc, char *argv[]) +{ + int ret; + progname = basename(argv[0]); + while (1) { + int c; + + c = getopt(argc, argv, "b:k:o:r:s:v:h"); + if (c == -1) + break; + + switch (c) { + case 'b': + board_name = optarg; + break; + case 'h': + usage(EXIT_SUCCESS); + break; + case 'k': + kernel.name = optarg; + break; + case 'o': + out.name = optarg; + break; + case 'r': + rootfs.name = optarg; + break; + case 's': + sscanf(optarg, "%u", &rootfs_size); + break; + case 'v': + version_name = optarg; + break; + default: + usage(EXIT_FAILURE); + break; + } + } + + ret = check_options(); + if (ret) + usage(EXIT_FAILURE); + + /* As ZyXEL Web-GUI only accept images with a rootfs equal or larger than the first firmware shipped + * for the device, we need to pad rootfs partition to this size. To perform further calculations, we + * decide the size of this part here. In case the rootfs we want to integrate in our image is larger, + * take it's size, otherwise the supplied size. + * + * Be careful! We rely on assertion of correct size to be performed beforehand. It is unknown if images + * with a to large rootfs are accepted or not. + */ + rootfs_out.size = rootfs_size < rootfs.size ? rootfs.size : rootfs_size; + return build_image(); +} |