ubnt-mkfwimage

/*
 * Copyright (C) 2007 Ubiquiti Networks, Inc.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <zlib.h>
#include <sys/mman.h>
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>
#include <limits.h>

#include "fw.h"

typedef struct part_data {
    char    partition_name[64];
    int     partition_index;
    u_int32_t   partition_baseaddr;
    u_int32_t   partition_memaddr;
    u_int32_t   partition_entryaddr;
    u_int32_t  partition_length;

    char    filename[PATH_MAX];
    struct stat stats;
} part_data_t;

#define MAX_SECTIONS    4
#define DEFAULT_OUTPUT_FILE     "firmware-image.bin"
#define DEFAULT_VERSION     "UNKNOWN"

#define OPTIONS "hv:o:i:"

static int debug = 0;

typedef struct image_info {
    char version[256];
    char outputfile[PATH_MAX];
    u_int32_t   part_count;
    part_data_t parts[MAX_SECTIONS];
} image_info_t;

static void write_header(void* mem, const char* version)
{
    header_t* header = mem;
    memset(header, 0, sizeof(header_t));

    memcpy(header->magic, MAGIC_HEADER, MAGIC_LENGTH);
    strncpy(header->version, version, sizeof(header->version));
    header->crc = htonl(crc32(0L, (unsigned char *)header,
                sizeof(header_t) - 2 * sizeof(u_int32_t)));
    header->pad = 0L;
}


static void write_signature(void* mem, u_int32_t sig_offset)
{
    /* write signature */
    signature_t* sign = (signature_t*)(mem + sig_offset);
    memset(sign, 0, sizeof(signature_t));

    memcpy(sign->magic, MAGIC_END, MAGIC_LENGTH);
    sign->crc = htonl(crc32(0L,(unsigned char *)mem, sig_offset));
    sign->pad = 0L;
}

static int write_part(void* mem, part_data_t* d)
{
    char* addr;
    int fd;
    part_t* p = mem;
    part_crc_t* crc = mem + sizeof(part_t) + d->stats.st_size;

    fd = open(d->filename, O_RDONLY);
    if (fd < 0)
    {
        ERROR("Failed opening file '%s'\n", d->filename);
        return -1;
    }

    if ((addr=(char*)mmap(0, d->stats.st_size, PROT_READ, MAP_SHARED, fd, 0)) == MAP_FAILED)
    {
        ERROR("Failed mmaping memory for file '%s'\n", d->filename);
        close(fd);
        return -2;
    }

    memcpy(mem + sizeof(part_t), addr, d->stats.st_size);
    munmap(addr, d->stats.st_size);

    memset(p->name, 0, sizeof(p->name));
    strncpy(p->magic, MAGIC_PART, MAGIC_LENGTH);
    strncpy(p->name, d->partition_name, sizeof(p->name));
    p->index = htonl(d->partition_index);
    p->data_size = htonl(d->stats.st_size);
    p->part_size = htonl(d->partition_length);
    p->baseaddr = htonl(d->partition_baseaddr);
    p->memaddr = htonl(d->partition_memaddr);
    p->entryaddr = htonl(d->partition_entryaddr);

    crc->crc = htonl(crc32(0L, mem, d->stats.st_size + sizeof(part_t)));
    crc->pad = 0L;

    return 0;
}

static void usage(const char* progname)
{
    INFO("Version %s\n"
             "Usage: %s [options]\n"
         "\t-v <version string>\t - firmware version information, default: %s\n"
         "\t-o <output file>\t - firmware output file, default: %s\n"
         "\t-i <input file>\t\t - firmware layout file, default: none\n"
         "\t-h\t\t\t - this help\n", VERSION,
         progname, DEFAULT_VERSION, DEFAULT_OUTPUT_FILE);
}

static void print_image_info(const image_info_t* im)
{
    int i = 0;
    INFO("Firmware version: '%s'\n"
         "Output file: '%s'\n"
         "Part count: %u\n",
         im->version, im->outputfile,
         im->part_count);

    for (i = 0; i < im->part_count; ++i)
    {
        const part_data_t* d = &im->parts[i];
        INFO(" %10s: %8ld bytes (free: %8ld)\n",
             d->partition_name,
             d->stats.st_size,
             d->partition_length - d->stats.st_size);
    }
}



/**
 * Image layout file format:
 *
 * <partition name>\t<partition index>\t<partition size>\t<data file name>
 *
 */
static int parse_image_layout(const char* layoutfile, image_info_t* im)
{
    int fd = 0;
    char line[1028];
    FILE* f;

    im->part_count = 0;

    fd = open(layoutfile, O_RDONLY);
    if (fd < 0) {
        ERROR("Could not open file '%s'\n", layoutfile);
        return -1;
    }

    f = fdopen(fd, "r");
    if (f == NULL) {
        close(fd);
        return -2;
    }

    while (!feof(f))
    {
        char name[32];
        u_int32_t index;
        u_int32_t baseaddr;
        u_int32_t size;
        u_int32_t memaddr;
        u_int32_t entryaddr;
        char file[PATH_MAX];
        u_int32_t c;
        part_data_t* d;

        if (fgets(line, sizeof(line), f) == NULL)
            break;

        // TODO: very inconvenient format, use smarter parsing someday
        if ((c = sscanf(line, "%32[^\t]\t%X\t%X\t%X\t%X\t%X\t%128[^\t\n]", name, &index, &baseaddr, &size, &memaddr, &entryaddr, file)) != 7)
                continue;

        DEBUG("%s\t\t0x%02X\t0x%08X\t0x%08X\t0x%08X\t0x%08X\t%s\n", name, index, baseaddr, size, memaddr, entryaddr, file);

        c = im->part_count;
        if (c == MAX_SECTIONS)
            break;

        d = &im->parts[c];
        strncpy(d->partition_name, name, sizeof(d->partition_name));
        d->partition_index = index;
        d->partition_baseaddr = baseaddr;
        d->partition_length = size;
        d->partition_memaddr = memaddr;
        d->partition_entryaddr = entryaddr;
        strncpy(d->filename, file, sizeof(d->filename));

        im->part_count++;
    }

    fclose(f);

    return 0;
}

/**
 * Checks the availability and validity of all image components.
 * Fills in stats member of the part_data structure.
 */
static int validate_image_layout(image_info_t* im)
{
    int i;

    if (im->part_count == 0 || im->part_count > MAX_SECTIONS)
    {
        ERROR("Invalid part count '%d'\n", im->part_count);
        return -1;
    }

    for (i = 0; i < im->part_count; ++i)
    {
        part_data_t* d = &im->parts[i];
        int len = strlen(d->partition_name);
        if (len == 0 || len > 16)
        {
            ERROR("Invalid partition name '%s' of the part %d\n",
                    d->partition_name, i);
            return -1;
        }
        if (stat(d->filename, &d->stats) < 0)
        {
            ERROR("Couldn't stat file '%s' from part '%s'\n",
                        d->filename, d->partition_name);
            return -2;
        }
        if (d->stats.st_size == 0)
        {
            ERROR("File '%s' from part '%s' is empty!\n",
                        d->filename, d->partition_name);
            return -3;
        }
        if (d->stats.st_size > d->partition_length) {
            ERROR("File '%s' too big (%d) - max size: 0x%08X (exceeds %lu bytes)\n",
                        d->filename, i, d->partition_length,
                    d->stats.st_size - d->partition_length);
            return -4;
        }
    }

    return 0;
}

static int build_image(image_info_t* im)
{
    char* mem;
    char* ptr;
    u_int32_t mem_size;
    FILE* f;
    int i;

    // build in-memory buffer
    mem_size = sizeof(header_t) + sizeof(signature_t);
    for (i = 0; i < im->part_count; ++i)
    {
        part_data_t* d = &im->parts[i];
        mem_size += sizeof(part_t) + d->stats.st_size + sizeof(part_crc_t);
    }

    mem = (char*)calloc(mem_size, 1);
    if (mem == NULL)
    {
        ERROR("Cannot allocate memory chunk of size '%u'\n", mem_size);
        return -1;
    }

    // write header
    write_header(mem, im->version);
    ptr = mem + sizeof(header_t);
    // write all parts
    for (i = 0; i < im->part_count; ++i)
    {
        part_data_t* d = &im->parts[i];
        int rc;
        if ((rc = write_part(ptr, d)) != 0)
        {
            ERROR("ERROR: failed writing part %u '%s'\n", i, d->partition_name);
        }
        ptr += sizeof(part_t) + d->stats.st_size + sizeof(part_crc_t);
    }
    // write signature
    write_signature(mem, mem_size - sizeof(signature_t));

    // write in-memory buffer into file
    if ((f = fopen(im->outputfile, "w")) == NULL)
    {
        ERROR("Can not create output file: '%s'\n", im->outputfile);
        return -10;
    }

    if (fwrite(mem, mem_size, 1, f) != 1)
    {
        ERROR("Could not write %d bytes into file: '%s'\n",
                mem_size, im->outputfile);
        return -11;
    }

    free(mem);
    fclose(f);
    return 0;
}


int main(int argc, char* argv[])
{
    char inputfile[PATH_MAX];
    int o, rc;
    image_info_t im;

    memset(&im, 0, sizeof(im));
    memset(inputfile, 0, sizeof(inputfile));

    strcpy(im.outputfile, DEFAULT_OUTPUT_FILE);
    strcpy(im.version, DEFAULT_VERSION);

    while ((o = getopt(argc, argv, OPTIONS)) != -1)
    {
        switch (o) {
        case 'v':
            if (optarg)
                strncpy(im.version, optarg, sizeof(im.version));
            break;
        case 'o':
            if (optarg)
                strncpy(im.outputfile, optarg, sizeof(im.outputfile));
            break;
        case 'i':
            if (optarg)
                strncpy(inputfile, optarg, sizeof(inputfile));
            break;
        case 'h':
            usage(argv[0]);
            return -1;
        }
    }

    if (strlen(inputfile) == 0)
    {
        ERROR("Input file is not specified, cannot continue\n");
        usage(argv[0]);
        return -2;
    }

    if ((rc = parse_image_layout(inputfile, &im)) != 0)
    {
        ERROR("Failed parsing firmware layout file '%s' - error code: %d\n",
            inputfile, rc);
        return -3;
    }

    if ((rc = validate_image_layout(&im)) != 0)
    {
        ERROR("Failed validating firmware layout - error code: %d\n", rc);
        return -4;
    }

    print_image_info(&im);

    if ((rc = build_image(&im)) != 0)
    {
        ERROR("Failed building image file '%s' - error code: %d\n", im.outputfile, rc);
        return -5;
    }

    return 0;
}