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  1. // dump.c -- information dumping routines for ifstool
  2.  
  3. // standard C includes
  4. #include <stdint.h>
  5. #include <stdbool.h>
  6. #include <stdlib.h>
  7. #include <stdarg.h>
  8. #include <stdio.h>
  9. #include <string.h>
  10. #include <errno.h>
  11. #include <sys/stat.h>
  12. #include <ctype.h>
  13. #include <time.h>
  14.  
  15. // platform-specific includes
  16. #ifdef _MSC_VER
  17. #include <direct.h>
  18. #include <sys/utime.h>
  19. #else // !_MSC_VER
  20. #include <sys/param.h>
  21. #include <unistd.h>
  22. #include <utime.h>
  23. #endif // _MSC_VER
  24.  
  25. // own includes
  26. #include "ucl/ucl.h"
  27. #include "minilzo.h"
  28. #include "buffer.h"
  29. #include "sha512.h"
  30. #include "ifsfile.h"
  31. #include "elffile.h"
  32. #include "utility.h"
  33.  
  34.  
  35. // imported global variables
  36. extern int verbose_level; // from ifstool.c
  37.  
  38.  
  39. // exported function prototypes
  40. int dump_ifs_info (const char *ifs_pathname, bool want_everything, bool hide_filename); // dumps detailed info about a particular IFS file on the standard output, returns 0 on success and >0 on error
  41. int dump_ifs_contents (const char *ifs_pathname, const char *outdir); // dumps the IFS filesystem contents in outdir, returns 0 on success and >0 on error
  42. int dump_file_hex (const char *pathname); // hexdump the content of pathname, returns 0 on success and != 0 on error
  43.  
  44.  
  45. // prototypes of local functions
  46. static int create_intermediate_dirs (const char *file_pathname); // creates all intermediate directories from root (or cwd) up to file_path, returns 0 on success and != 0 on error
  47. static void hex_fprintf (FILE *fp, const uint8_t *data, size_t data_size, int howmany_columns, const char *fmt, ...); // hexdump-style formatted output to a file stream (which may be stdout/stderr)
  48. static char *binary (const uint8_t x, char char_for_zero, char char_for_one); // returns the binary representation of x as a string
  49. static char *describe_uint8 (const uint8_t x, const char *bitwise_stringdescs[8]); // returns the ORed description of byte 'x' according to the description strings for each bit
  50.  
  51.  
  52. // imported function prototypes
  53. extern int32_t update_checksum (const void *data, const size_t data_len, const bool is_foreign_endianness); // from ifstool.c
  54.  
  55.  
  56. static int create_intermediate_dirs (const char *file_pathname)
  57. {
  58.    // creates all intermediate directories from root (or cwd) up to file_path
  59.  
  60.    char *temp_pathname;
  61.    char *separator;
  62.    char *ctx;
  63.    size_t string_index;
  64.    size_t length;
  65.  
  66.    temp_pathname = strdup (file_pathname); // have a working copy of file_pathname
  67.    if (temp_pathname == NULL)
  68.       return (-1); // on strdup() failure, return an error value (errno is set)
  69.    length = strlen (temp_pathname);
  70.    for (string_index = length - 1; string_index != SIZE_MAX; string_index--) // i.e. loop until it overflows
  71.       if ((temp_pathname[string_index] == '/') || (temp_pathname[string_index] == '\\'))
  72.          break; // look for the last directory separator and stop as soon as we find it
  73.    if (string_index != SIZE_MAX)
  74.    {
  75.       for (; string_index < length; string_index++)
  76.          temp_pathname[string_index] = 0; // if we found one, break there so as to have just the path and clear the rest of the string
  77.       separator = strtok_r (&temp_pathname[1], "/\\", &ctx); // for each separator in the remaining string past the first one...
  78.       while (separator != NULL)
  79.       {
  80.          (void) mkdir (temp_pathname, 0755); // create directories recursively
  81.          temp_pathname[strlen (temp_pathname)] = '/'; // put the separator back
  82.          separator = strtok_r (NULL, "/\\", &ctx); // and look for the next one
  83.       }
  84.    }
  85.  
  86.    free (temp_pathname); // release our working copy of file_pathname
  87.    return (0);
  88. }
  89.  
  90.  
  91. static void hex_fprintf (FILE *fp, const uint8_t *data, size_t data_size, int howmany_columns, const char *fmt, ...)
  92. {
  93.    // this function logs hexadecimal data to an opened file pointer (or to stdout/stderr)
  94.  
  95.    va_list argptr;
  96.    size_t index;
  97.    int i;
  98.  
  99.    // concatenate all the arguments in one string and write it to the file
  100.    va_start (argptr, fmt);
  101.    vfprintf (fp, fmt, argptr);
  102.    va_end (argptr);
  103.  
  104.    // for each row of howmany_columns bytes of data...
  105.    for (index = 0; index < data_size; index += howmany_columns)
  106.    {
  107.       fprintf (fp, "    %05zu  ", index); // print array address of row
  108.       for (i = 0; i < howmany_columns; i++)
  109.          if (index + i < data_size)
  110.             fprintf (fp, " %02X", data[index + i]); // if row contains data, print data as hex bytes
  111.          else
  112.             fprintf (fp, "   "); // else fill the space with blanks
  113.       fprintf (fp, "   ");
  114.       for (i = 0; i < howmany_columns; i++)
  115.          if (index + i < data_size)
  116.             fputc ((data[index + i] >= 32) && (data[index + i] < 127) ? data[index + i] : '.', fp); // now if row contains data, print data as ASCII
  117.          else
  118.             fputc (' ', fp); // else fill the space with blanks
  119.       fputc ('\n', fp);
  120.    }
  121.  
  122.    return; // and return
  123. }
  124.  
  125.  
  126. static char *binary (const uint8_t x, char char_for_zero, char char_for_one)
  127. {
  128.    // returns the binary representation of x as a string
  129.  
  130.    static thread_local char outstr[9] = "00000000";
  131.    for (int i = 0; i < 8; i++)
  132.       outstr[i] = (x & (0x80 >> i) ? char_for_one : char_for_zero);
  133.    return (outstr);
  134. }
  135.  
  136.  
  137. static char *describe_uint8 (const uint8_t x, const char *bitwise_stringdescs[8])
  138. {
  139.    // returns the ORed description of byte 'x' according to the description strings for each bit
  140.  
  141.    static char *default_bitstrings[8] = { "bit0", "bit1", "bit2", "bit3", "bit4", "bit5", "bit6", "bit7" };
  142.    static thread_local char outstr[8 * 64] = "";
  143.  
  144.    outstr[0] = 0;
  145.    for (int i = 0; i < 8; i++)
  146.       if (x & (1 << i))
  147.       {
  148.          if (outstr[0] != 0)
  149.             strcat_s (outstr, sizeof (outstr), "|");
  150.          strcat_s (outstr, sizeof (outstr), ((bitwise_stringdescs != NULL) && (*bitwise_stringdescs[i] != 0) ? bitwise_stringdescs[i] : default_bitstrings[i]));
  151.       }
  152.    return (outstr);
  153. }
  154.  
  155.  
  156. int dump_ifs_info (const char *ifs_pathname, bool want_everything, bool hide_filename)
  157. {
  158.    #define hex_printf(buf,size,...) do { \
  159.       if (want_everything || ((size) <= 16 * 1024)) /* only print when it's not too big (up to 16 kb) */\
  160.          hex_fprintf (stdout, (buf), (size), 16, __VA_ARGS__); /* use 16 columns in hex output to stdout */ \
  161.       else { \
  162.          printf (__VA_ARGS__); \
  163.          hex_fprintf (stdout, (buf), 1024, 16, "   first kilobyte:\n"); \
  164.       } \
  165.    } while (0)
  166.    #define BINARY(x) binary ((x), '-', 'x')
  167.  
  168.    static const char *startupheader_flags1_strings[8] = {
  169.       "VIRTUAL", // bit 0
  170.       "BIGENDIAN", // bit 1
  171.       "COMPRESS_BIT1", // bit 2
  172.       "COMPRESS_BIT2", // bit 3
  173.       "COMPRESS_BIT3", // bit 4
  174.       "TRAILER_V2", // bit 5
  175.       "", // bit 6
  176.       "", // bit 7
  177.    };
  178.    static const char *imageheader_flags_strings[8] = {
  179.       "BIGENDIAN", // bit 0
  180.       "READONLY", // bit 1
  181.       "INO_BITS", // bit 2
  182.       "SORTED", // bit 3
  183.       "TRAILER_V2", // bit 4
  184.       "", // bit 5
  185.       "", // bit 6
  186.       "", // bit 7
  187.    };
  188.  
  189.    startup_header_t *startup_header = NULL;
  190.    size_t startupheader_offset = 0;
  191.    startup_trailer_v1_t *startup_trailer_v1 = NULL;
  192.    startup_trailer_v2_t *startup_trailer_v2 = NULL;
  193.    size_t startuptrailer_offset = 0;
  194.    image_header_t *image_header = NULL;
  195.    size_t imageheader_offset = 0;
  196.    image_trailer_v1_t *image_trailer_v1 = NULL;
  197.    image_trailer_v2_t *image_trailer_v2 = NULL;
  198.    size_t imagetrailer_offset = 0;
  199.    fsentry_t **fsentries = NULL; // mallocated
  200.    size_t fsentry_count = 0;
  201.    fsentry_t *current_fsentry = NULL;
  202.    buffer_t decompression_dst;
  203.    char recorded_sha512[2 * SHA512_DIGEST_LENGTH + 1] = "";
  204.    char computed_sha512[2 * SHA512_DIGEST_LENGTH + 1] = "";
  205.    size_t startupfile_blobsize = 0;
  206.    size_t compressed_blocksize;
  207.    void *reallocated_ptr;
  208.    bool is_foreign_endianness;
  209.    uint8_t *decompressor_out;
  210.    uint8_t *decompressor_in;
  211.    size_t decompressor_outlen;
  212.    size_t bootfile_blobsize = 0;
  213.    size_t current_offset;
  214.    size_t fsentry_index;
  215.    size_t nearest_distance;
  216.    size_t nearest_index;
  217.    size_t byte_index;
  218.    uint32_t recorded_checksum;
  219.    uint32_t computed_checksum;
  220.    buffer_t file;
  221.    time_t mtime;
  222.    int cf;
  223.  
  224.    // open and read IFS file
  225.    if (!Buffer_ReadFromFile (&file, ifs_pathname))
  226.       DIE_WITH_EXITCODE (1, "can't open \"%s\" for reading: %s", ifs_pathname, strerror (errno));
  227.  
  228.    printf ("QNX In-kernel Filesystem analysis produced by ifstool version " VERSION_FMT_YYYYMMDD "\n", VERSION_ARG_YYYYMMDD);
  229.    if (hide_filename)
  230.       printf ("IFS file - size 0x%zx (%zd) bytes\n", file.size, file.size);
  231.    else
  232.       printf ("IFS file \"%s\" - size 0x%zx (%zd) bytes\n", ifs_pathname, file.size, file.size);
  233.  
  234.    // parse file from start to end
  235.    current_offset = 0;
  236.    cf = STARTUP_HDR_FLAGS1_COMPRESS_NONE;
  237.    for (;;)
  238.    {
  239.       // does a startup header start here ?
  240.       if ((current_offset + sizeof (startup_header_t) < file.size)
  241.           && (startup_header == NULL)
  242.           && (memcmp (&file.bytes[current_offset], "\xeb\x7e\xff\x00", 4) == 0))
  243.       {
  244.          startupheader_offset = current_offset;
  245.          startup_header = (startup_header_t *) &file.bytes[startupheader_offset];
  246.  
  247.          // layout:
  248.          // [STARTUP HEADER]
  249.          // (startup file blob)
  250.          // [STARTUP TRAILER v1 or v2]
  251.  
  252.          printf ("\n");
  253.          printf ("Startup header at offset 0x%zx (%zd):\n", current_offset, current_offset);
  254.          printf ("   signature     = %02x %02x %02x %02x - good\n", startup_header->signature[0], startup_header->signature[1], startup_header->signature[2], startup_header->signature[3]);
  255.          printf ("   version       = 0x%04x (%d) - %s\n", startup_header->version, startup_header->version, (startup_header->version == 1 ? "looks good" : "???"));
  256.          cf = startup_header->flags1 & STARTUP_HDR_FLAGS1_COMPRESS_MASK;
  257.          printf ("   flags1        = 0x%02x (%s) - %s\n", startup_header->flags1, describe_uint8 (startup_header->flags1, startupheader_flags1_strings), (cf == STARTUP_HDR_FLAGS1_COMPRESS_NONE ? "uncompressed image" : (cf == STARTUP_HDR_FLAGS1_COMPRESS_ZLIB ? "Zlib-compressed image (non-bootable)" : (cf == STARTUP_HDR_FLAGS1_COMPRESS_LZO ? "LZO-compressed image" : (cf == STARTUP_HDR_FLAGS1_COMPRESS_UCL ? "UCL-compressed image" : "compressed image (unknown algorithm)")))));
  258.          printf ("   flags2        = 0x%02x (%s) - %s\n", startup_header->flags2, BINARY (startup_header->flags2), (startup_header->flags2 == 0 ? "looks good" : "???"));
  259.          printf ("   header_size   = 0x%04x (%d) - %s\n", startup_header->header_size, startup_header->header_size, (startup_header->header_size == sizeof (startup_header_t) ? "looks good" : "BAD"));
  260.          printf ("   machine       = 0x%04x (%d) - %s\n", startup_header->machine, startup_header->machine, (startup_header->machine == ELF_MACHINE_X86_64 ? "x86_64" : (startup_header->machine == ELF_MACHINE_AARCH64 ? "aarch64" : "unknown")));
  261.          printf ("   startup_vaddr = 0x%08x (%d) - virtual address to transfer to after IPL is done\n", startup_header->startup_vaddr, startup_header->startup_vaddr);
  262.          printf ("   paddr_bias    = 0x%08x (%d) - value to add to physical addresses to get an indirectable pointer value\n", startup_header->paddr_bias, startup_header->paddr_bias);
  263.          printf ("   image_paddr   = 0x%08x (%d) - physical address of image\n", startup_header->image_paddr, startup_header->image_paddr);
  264.          printf ("   ram_paddr     = 0x%08x (%d) - physical address of RAM to copy image to (startup_size bytes copied)\n", startup_header->ram_paddr, startup_header->ram_paddr);
  265.          printf ("   ram_size      = 0x%08x (%d) - amount of RAM used by the startup program and executables in the fs\n", startup_header->ram_size, startup_header->ram_size);
  266.          printf ("   startup_size  = 0x%08x (%d) - size of startup (never compressed) - %s\n", startup_header->startup_size, startup_header->startup_size, (current_offset + sizeof (image_header_t) + startup_header->startup_size + (startup_header->flags1 & STARTUP_HDR_FLAGS1_TRAILER_V2 ? sizeof (image_trailer_v2_t) : sizeof (image_trailer_v1_t)) < file.size ? "looks good" : "BAD (IFS file too short)"));
  267.          printf ("   stored_size   = 0x%08x (%d) - stored size of image - %s\n", startup_header->stored_size, startup_header->stored_size, (startup_header->stored_size <= startup_header->ram_size ? "looks good" : "???"));
  268.          printf ("   imagefs_paddr = 0x%08x (%d) - set by IPL when startup runs - %s\n", startup_header->imagefs_paddr, startup_header->imagefs_paddr, (startup_header->imagefs_paddr == 0 ? "looks good" : "??? should be zero"));
  269.          printf ("   imagefs_size  = 0x%08x (%d) - size of uncompressed imagefs\n", startup_header->imagefs_size, startup_header->imagefs_size);
  270.          printf ("   preboot_size  = 0x%04x (%d) - size of loaded before header - %s\n", startup_header->preboot_size, startup_header->preboot_size, (startup_header->preboot_size == current_offset ? "looks good" : "???"));
  271.          printf ("   zero0         = 0x%04x (%d) - zeros - %s\n", startup_header->zero0, startup_header->zero0, (startup_header->zero0 == 0 ? "looks good" : "??? should be zero"));
  272.          printf ("   zero[0]       = 0x%08x (%d) - zeros - %s\n", startup_header->zero[0], startup_header->zero[0], (startup_header->zero[0] == 0 ? "looks good" : "??? should be zero"));
  273.          printf ("   addr_off      = 0x%016llx (%lld) - offset for startup_vaddr and [image|ram|imagefs]_paddr - %s\n", (unsigned long long) startup_header->addr_off, (unsigned long long) startup_header->addr_off, (startup_header->addr_off == 0 ? "looks good" : "??? should be zero"));
  274.          hex_printf ((uint8_t *) &startup_header->info[0], sizeof (startup_header->info), "   info[48] =\n");
  275.  
  276.          // validate that the file can contain up to the startup trailer
  277.          if (current_offset + startup_header->startup_size > file.size)
  278.          {
  279.             LOG_WARNING ("this IFS file is corrupted (startup trailer extends past end of file)");
  280.             goto endofdata;
  281.          }
  282.  
  283.          // check if this endianness is ours
  284.          if (   ( (startup_header->flags1 & STARTUP_HDR_FLAGS1_BIGENDIAN) && (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__))
  285.              || (!(startup_header->flags1 & STARTUP_HDR_FLAGS1_BIGENDIAN) && (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)))
  286.             is_foreign_endianness = true; // if the header is big endian and we're on a little endian machine, or the other way around, it's a foreign endianness
  287.          else
  288.             is_foreign_endianness = false; // else this header is for the same endianness as us
  289.  
  290.          // locate the right startup trailer at the right offset
  291.          if (startup_header->flags1 & STARTUP_HDR_FLAGS1_TRAILER_V2)
  292.          {
  293.             startuptrailer_offset = current_offset + startup_header->startup_size - sizeof (startup_trailer_v2_t);
  294.             startup_trailer_v2 = (startup_trailer_v2_t *) &file.bytes[startuptrailer_offset];
  295.             startupfile_blobsize = startup_header->startup_size - sizeof (startup_header_t) - sizeof (startup_trailer_v2_t);
  296.          }
  297.          else // old V1 trailer
  298.          {
  299.             startuptrailer_offset = current_offset + startup_header->startup_size - sizeof (startup_trailer_v1_t);
  300.             startup_trailer_v1 = (startup_trailer_v1_t *) &file.bytes[startuptrailer_offset];
  301.             startupfile_blobsize = startup_header->startup_size - sizeof (startup_header_t) - sizeof (startup_trailer_v1_t);
  302.          }
  303.  
  304.          current_offset += sizeof (startup_header_t); // jump over the startup header and reach the startup blob
  305.          printf ("\n");
  306.          printf ("Startup blob at offset 0x%zx (%zd):\n", current_offset, current_offset);
  307.          printf ("   size 0x%zx (%zd) bytes\n", startupfile_blobsize, startupfile_blobsize);
  308.          printf ("   checksum 0x%08x\n", update_checksum (&file.bytes[current_offset], startupfile_blobsize, is_foreign_endianness));
  309.  
  310.          current_offset += startupfile_blobsize; // jump over the startup blob and reach the startup trailer
  311.          printf ("\n");
  312.          printf ("Startup trailer at offset 0x%zx (%zd) - version %d:\n", current_offset, current_offset, (startup_header->flags1 & STARTUP_HDR_FLAGS1_TRAILER_V2 ? 2 : 1));
  313.          if (startup_header->flags1 & STARTUP_HDR_FLAGS1_TRAILER_V2)
  314.          {
  315.             for (byte_index = 0; byte_index < SHA512_DIGEST_LENGTH; byte_index++)
  316.                sprintf_s (&recorded_sha512[2 * byte_index], 3, "%02x", startup_trailer_v2->sha512[byte_index]);
  317.             strcpy_s (computed_sha512, sizeof (computed_sha512), SHA512 (startup_header, startuptrailer_offset - startupheader_offset, NULL));
  318.             recorded_checksum = startup_trailer_v2->cksum;
  319.             computed_checksum = update_checksum (startup_header, startuptrailer_offset + SHA512_DIGEST_LENGTH - startupheader_offset, is_foreign_endianness);
  320.             printf ("    sha512([0x%zx-0x%zx[) = %s - %s\n", startupheader_offset, startuptrailer_offset, recorded_sha512, (strcasecmp (computed_sha512, recorded_sha512) == 0 ? "GOOD" : "BAD"));
  321.             printf ("    cksum([0x%zx-0x%zx[) = 0x%08x - %s\n", startupheader_offset, startuptrailer_offset + SHA512_DIGEST_LENGTH, recorded_checksum, (computed_checksum == recorded_checksum ? "GOOD" : "BAD"));
  322.             if (strcasecmp (computed_sha512, recorded_sha512) != 0)
  323.                printf ("Computed SHA-512: %s\n", computed_sha512);
  324.             if (computed_checksum != recorded_checksum)
  325.                printf ("Computed cksum: 0x%08x\n", computed_checksum);
  326.          }
  327.          else // old v1 trailer
  328.          {
  329.             recorded_checksum = startup_trailer_v1->cksum;
  330.             computed_checksum = update_checksum (startup_header, sizeof (startup_header) + startupfile_blobsize, is_foreign_endianness);
  331.             printf ("    cksum([0x%zx-0x%zx[) = 0x%08x - %s\n", startupheader_offset, startuptrailer_offset, recorded_checksum, (computed_checksum == recorded_checksum ? "GOOD" : "BAD"));
  332.             if (computed_checksum != recorded_checksum)
  333.                printf ("Computed cksum: 0x%08x\n", computed_checksum);
  334.          }
  335.  
  336.          current_offset += (startup_header->flags1 & STARTUP_HDR_FLAGS1_TRAILER_V2 ? sizeof (startup_trailer_v2_t) : sizeof (startup_trailer_v1_t)); // now reach the next segment
  337.       }
  338.  
  339.       // else does an image header start here ?
  340.       else if ((current_offset + sizeof (image_header_t) < file.size)
  341.                && (image_header == NULL)
  342.                && (   ((cf == STARTUP_HDR_FLAGS1_COMPRESS_NONE) && (memcmp (&file.bytes[current_offset], "imagefs", 7) == 0))
  343.                    || (cf != STARTUP_HDR_FLAGS1_COMPRESS_NONE) && (startup_header->imagefs_size > 0)))
  344.       {
  345.          imageheader_offset = current_offset;
  346.          image_header = (image_header_t *) &file.bytes[imageheader_offset];
  347.  
  348.          // should we decompress it ?
  349.          if (cf != STARTUP_HDR_FLAGS1_COMPRESS_NONE)
  350.          {
  351.             // it appears mkifs compresses data in blocks, prefixed by 2-byte block size in BIG ENDIAN
  352.             Buffer_InitWithSize (&decompression_dst, startup_header->imagefs_size * 11 / 10); // mallocate and add 10% for safety
  353.             decompression_dst.size = 0;
  354.  
  355.             if (cf == STARTUP_HDR_FLAGS1_COMPRESS_UCL)
  356.                ASSERT (ucl_init () == UCL_E_OK, "UCL library initialization failed -- please recompile this tool with less aggressive optimizations");
  357.             else if (cf == STARTUP_HDR_FLAGS1_COMPRESS_LZO)
  358.                ASSERT (lzo_init () == LZO_E_OK, "LZO library initialization failed -- please recompile this tool with less aggressive optimizations");
  359.             else if (cf == STARTUP_HDR_FLAGS1_COMPRESS_ZLIB)
  360.             {
  361.                LOG_WARNING ("unimplemented compression scheme: zlib (FIXME)");
  362.                goto endofdata;
  363.             }
  364.             else
  365.             {
  366.                LOG_WARNING ("unsupported compression flags: 0x%2x", cf);
  367.                goto endofdata;
  368.             }
  369.  
  370.             // run the compressed payload (the imagefs) through the right decompression algorithm
  371.             for (;;)
  372.             {
  373.                compressed_blocksize = (file.bytes[current_offset + 0] << 8) | (file.bytes[current_offset + 1] << 0); // read block size word (in big engian)
  374.                current_offset += 2; // skip it
  375.                if (compressed_blocksize == 0)
  376.                   break; // a nil block size means end of stream is reached
  377.                LOG_DEBUG ("about to decompress block of %zd bytes", compressed_blocksize);
  378.                decompressor_in = &file.bytes[current_offset];
  379.                decompressor_out = &decompression_dst.bytes[decompression_dst.size];
  380.                decompressor_outlen = 0;
  381.  
  382.                if (cf == STARTUP_HDR_FLAGS1_COMPRESS_UCL)
  383.                {
  384.                   // UCL compression. NOTE: the decompressor function used in startup-x86 is "ucl_nrv2b_decompress_8 / ucl_nrv2b_decompress_le16 / ucl_nrv2b_decompress_le32"
  385.                   static ucl_uint ucl_outlen; // have a different variable because of pointer size mismatch
  386.                   if (ucl_nrv2b_decompress_8 (decompressor_in, (ucl_uint) compressed_blocksize, decompressor_out, &ucl_outlen, NULL) != UCL_E_OK)
  387.                   {
  388.                      LOG_WARNING ("this IFS file is corrupted (UCL decompression failed)");
  389.                      goto endofdata;
  390.                   }
  391.                   decompressor_outlen = ucl_outlen;
  392.                }
  393.                else if (cf == STARTUP_HDR_FLAGS1_COMPRESS_LZO)
  394.                {
  395.                   // LZO decompression. NOTE: mkifs uses the full LZO package, whereas I use minilzo.
  396.                   static lzo_uint lzo_outlen; // have a different variable because of pointer size mismatch
  397.                   if (lzo1x_decompress (decompressor_in, (lzo_uint) compressed_blocksize, decompressor_out, &lzo_outlen, NULL) != LZO_E_OK)
  398.                   {
  399.                      LOG_WARNING ("this IFS file is corrupted (UCL decompression failed)");
  400.                      goto endofdata;
  401.                   }
  402.                   decompressor_outlen = lzo_outlen;
  403.                }
  404.                else if (cf == STARTUP_HDR_FLAGS1_COMPRESS_ZLIB)
  405.                   ; // TODO
  406.  
  407.                current_offset += compressed_blocksize;
  408.                decompression_dst.size += decompressor_outlen;
  409.             }
  410.  
  411.             LOG_INFO ("decompressed %zd bytes into %zd bytes\n", file.size - imageheader_offset, decompression_dst.size);
  412.  
  413.             // now place the decompressed buffer in the payload at the imagefs offset
  414.             ASSERT_WITH_ERRNO (Buffer_WriteBufferAt (&file, imageheader_offset, &decompression_dst));
  415.             current_offset = imageheader_offset; // jump back to where we put the uncompressed data
  416.             file.size = imageheader_offset + decompression_dst.size; // update IFS data size
  417.  
  418.             startup_header = (startup_header_t *) &file.bytes[startupheader_offset]; // fix the pointers that might have changed
  419.             if (startup_header->flags1 & STARTUP_HDR_FLAGS1_TRAILER_V2)
  420.                startup_trailer_v2 = (startup_trailer_v2_t *) &file.bytes[startuptrailer_offset];
  421.             else // old V1 trailer
  422.                startup_trailer_v1 = (startup_trailer_v1_t *) &file.bytes[startuptrailer_offset];
  423.             image_header = (image_header_t *) &file.bytes[imageheader_offset]; // fix the pointers that might have changed
  424.          }
  425.  
  426.          // layout:
  427.          // [IMAGE HEADER]
  428.          // [image directory entries]
  429.          // [smallest file blobs up to KERNEL]
  430.          // [padding]
  431.          // [KERNEL]
  432.          // [rest of file blobs]
  433.          // [IMAGE FOOTER]
  434.  
  435.          printf ("\n");
  436.          printf ("Image header at offset %zx (%zd):\n", current_offset, current_offset);
  437.          printf ("   signature    = %02x %02x %02x %02x %02x %02x %02x (\"%.7s\") - good\n", image_header->signature[0], image_header->signature[1], image_header->signature[2], image_header->signature[3], image_header->signature[4], image_header->signature[5], image_header->signature[6], image_header->signature);
  438.          printf ("   flags        = 0x%02x (%s)\n", image_header->flags, describe_uint8 (image_header->flags, imageheader_flags_strings));
  439.          printf ("   image_size   = 0x%08x (%d) - size from header to end of trailer - %s\n", image_header->image_size, image_header->image_size, (current_offset + image_header->image_size <= file.size ? "looks good" : "BAD (IFS file too short)"));
  440.          printf ("   hdr_dir_size = 0x%08x (%d) - size from header to last dirent - %s\n", image_header->hdr_dir_size, image_header->hdr_dir_size, (current_offset + image_header->hdr_dir_size < file.size ? "looks good" : "BAD (IFS file too short)"));
  441.          printf ("   dir_offset   = 0x%08x (%d) - offset from header to first dirent - %s\n", image_header->dir_offset, image_header->dir_offset, (current_offset + image_header->dir_offset >= file.size ? "BAD (IFS file too short)" : (image_header->dir_offset > image_header->hdr_dir_size ? "BAD" : "looks good")));
  442.          printf ("   boot_ino[4]  = { 0x%08x, 0x%08x, 0x%08x, 0x%08x }\n", image_header->boot_ino[0], image_header->boot_ino[1], image_header->boot_ino[2], image_header->boot_ino[3]);
  443.          printf ("   script_ino   = 0x%08x (%d) - inode of compiled bootscript\n", image_header->script_ino, image_header->script_ino);
  444.          printf ("   chain_paddr  = 0x%08x (%d) - offset to next fs signature\n", image_header->chain_paddr, image_header->chain_paddr);
  445.          hex_printf ((uint8_t *) &image_header->spare[0], sizeof (image_header->spare), "   spare[10] =\n");
  446.          printf ("   mountflags   = 0x%08x (%s %s %s %s)\n", image_header->mountflags, BINARY (((uint8_t *) &image_header->mountflags)[0]), BINARY (((uint8_t *) &image_header->mountflags)[1]), BINARY (((uint8_t *) &image_header->mountflags)[2]), BINARY (((uint8_t *) &image_header->mountflags)[3]));
  447.          printf ("   mountpoint   = \"%s\"\n", image_header->mountpoint);
  448.  
  449.          // validate that the file can contain up to the image trailer
  450.          if (current_offset + image_header->image_size > file.size)
  451.          {
  452.             LOG_WARNING ("this IFS file is corrupted (image trailer extends past end of file)");
  453.             goto endofdata;
  454.          }
  455.  
  456.          // check if this endianness is ours
  457.          if (   ( (image_header->flags & IMAGE_FLAGS_BIGENDIAN) && (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__))
  458.              || (!(image_header->flags & IMAGE_FLAGS_BIGENDIAN) && (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)))
  459.             is_foreign_endianness = true; // if the header is big endian and we're on a little endian machine, or the other way around, it's a foreign endianness
  460.          else
  461.             is_foreign_endianness = false; // else this header is for the same endianness as us
  462.  
  463.          // locate the image trailer at the right offset
  464.          if (image_header->flags & IMAGE_FLAGS_TRAILER_V2)
  465.          {
  466.             imagetrailer_offset = current_offset + image_header->image_size - sizeof (image_trailer_v2_t);
  467.             image_trailer_v2 = (image_trailer_v2_t *) &file.bytes[imagetrailer_offset];
  468.          }
  469.          else // old V1 trailer
  470.          {
  471.             imagetrailer_offset = current_offset + image_header->image_size - sizeof (image_trailer_v1_t);
  472.             image_trailer_v1 = (image_trailer_v1_t *) &file.bytes[imagetrailer_offset];
  473.          }
  474.  
  475.          current_offset += sizeof (image_header_t); // jump over the image header and reach the first directory entry
  476.  
  477.          // there may be padding before the first directory entry
  478.          if (image_header->dir_offset - sizeof (image_header_t) > 0)
  479.             hex_printf (&file.bytes[current_offset], image_header->dir_offset - sizeof (image_header_t), "\n" "%zd padding bytes at offset 0x%zd (%zd):\n", image_header->dir_offset - sizeof (image_header_t), current_offset, current_offset);
  480.          current_offset += image_header->dir_offset - sizeof (image_header_t); // padding was processed, jump over it
  481.  
  482.          // dump all directory entries until the last one included
  483.          fsentries = NULL;
  484.          fsentry_count = 0;
  485.          while (current_offset < imageheader_offset + image_header->hdr_dir_size)
  486.          {
  487.             current_fsentry = (fsentry_t *) &file.bytes[current_offset];
  488.  
  489.             if (imageheader_offset + image_header->hdr_dir_size - current_offset < sizeof (current_fsentry->header))
  490.                break; // end padding reached
  491.  
  492.             // stack up the filesystem entry pointers in an array while we read them
  493.             reallocated_ptr = realloc (fsentries, (fsentry_count + 1) * sizeof (fsentry_t *));
  494.             ASSERT_WITH_ERRNO (reallocated_ptr);
  495.             fsentries = reallocated_ptr;
  496.             fsentries[fsentry_count] = current_fsentry;
  497.             fsentry_count++;
  498.  
  499.             printf ("\n");
  500.             printf ("Filesystem entry at offset 0x%zx (%zd) - last one at 0x%zx (%zd):\n", current_offset, current_offset, imageheader_offset + image_header->hdr_dir_size, imageheader_offset + image_header->hdr_dir_size);
  501.             printf ("   size           = 0x%04x (%d) - size of dirent - %s\n", current_fsentry->header.size, current_fsentry->header.size, ((current_fsentry->header.size > 0) && (current_offset + current_fsentry->header.size < file.size) ? "looks good" : "BAD"));
  502.             printf ("   extattr_offset = 0x%04x (%d) - %s\n", current_fsentry->header.extattr_offset, current_fsentry->header.extattr_offset, (current_fsentry->header.extattr_offset == 0 ? "no extattr" : "has extattr"));
  503.             printf ("   ino            = 0x%08x (%d) - inode number (%s%s%s%s)\n", current_fsentry->header.ino, current_fsentry->header.ino, (current_fsentry->header.ino & 0xE0000000 ? "is" : "nothing special"), (current_fsentry->header.ino & IFS_INO_PROCESSED_ELF ? " PROCESSED_ELF" : ""), (current_fsentry->header.ino & IFS_INO_RUNONCE_ELF ? " RUNONCE_ELF" : ""), (current_fsentry->header.ino & IFS_INO_BOOTSTRAP_EXE ? " BOOTSTRAP_EXE" : ""));
  504.             printf ("   mode           = 0x%08x (%d) - %s (0%o), POSIX permissions 0%o\n", current_fsentry->header.mode, current_fsentry->header.mode, (S_ISDIR (current_fsentry->header.mode) ? "directory" : (S_ISREG (current_fsentry->header.mode) ? "file" : (S_ISLNK (current_fsentry->header.mode) ? "symlink" : "device"))), (current_fsentry->header.mode & 0xF000) >> 12, current_fsentry->header.mode & 0xFFF);
  505.             printf ("   gid            = 0x%08x (%d) - owner group ID%s\n", current_fsentry->header.gid, current_fsentry->header.gid, (current_fsentry->header.gid == 0 ? " (root)" : ""));
  506.             printf ("   uid            = 0x%08x (%d) - owner user ID%s\n", current_fsentry->header.uid, current_fsentry->header.uid, (current_fsentry->header.uid == 0 ? " (root)" : ""));
  507.             mtime = (time_t) current_fsentry->header.mtime;
  508.             printf ("   mtime          = 0x%08x (%d) - POSIX timestamp: %s", current_fsentry->header.mtime, current_fsentry->header.mtime, asctime (localtime (&mtime))); // NOTE: asctime() provides the newline
  509.             if (S_ISDIR (current_fsentry->header.mode))
  510.                printf ("   [DIRECTORY] path = \"%s\"\n", (char *) &current_fsentry->u.dir.path); // convert from pointer to char array
  511.             else if (S_ISREG (current_fsentry->header.mode))
  512.             {
  513.                printf ("   [FILE] offset = 0x%08x (%d) - %s\n", current_fsentry->u.file.offset, current_fsentry->u.file.offset, (imageheader_offset + current_fsentry->u.file.offset < file.size ? "looks good" : "BAD (IFS file too short)"));
  514.                printf ("   [FILE] size   = 0x%08x (%d) - %s\n", current_fsentry->u.file.size, current_fsentry->u.file.size, (imageheader_offset + current_fsentry->u.file.offset + current_fsentry->u.file.size < file.size ? "looks good" : "BAD (IFS file too short)"));
  515.                printf ("   [FILE] path   = \"%s\"\n", (char *) &current_fsentry->u.file.path); // convert from pointer to char array
  516.             }
  517.             else if (S_ISLNK (current_fsentry->header.mode))
  518.             {
  519.                printf ("   [SYMLINK] sym_offset = 0x%04x (%d) - %s\n", current_fsentry->u.symlink.sym_offset, current_fsentry->u.symlink.sym_offset, (sizeof (current_fsentry->header) + 2 * sizeof (uint16_t) + current_fsentry->u.symlink.sym_offset <= current_fsentry->header.size ? "looks good" : "BAD (dirent too short)"));
  520.                printf ("   [SYMLINK] sym_size   = 0x%04x (%d) - %s\n", current_fsentry->u.symlink.sym_size, current_fsentry->u.symlink.sym_size, (sizeof (current_fsentry->header) + 2 * sizeof (uint16_t) + current_fsentry->u.symlink.sym_offset + current_fsentry->u.symlink.sym_size <= current_fsentry->header.size ? "looks good" : "BAD (dirent too short)"));
  521.                printf ("   [SYMLINK] path       = \"%s\"\n", (char *) &current_fsentry->u.symlink.path); // convert from pointer to char array
  522.                printf ("   [SYMLINK] contents   = \"%s\"\n", ((char *) &current_fsentry->u.symlink.path) + current_fsentry->u.symlink.sym_offset); // convert from pointer to char array
  523.             }
  524.             else // can only be a device
  525.             {
  526.                printf ("   [DEVICE] dev  = 0x%08x (%d)\n", current_fsentry->u.device.dev, current_fsentry->u.device.dev);
  527.                printf ("   [DEVICE] rdev = 0x%08x (%d)\n", current_fsentry->u.device.rdev, current_fsentry->u.device.rdev);
  528.                printf ("   [DEVICE] path = \"%s\"\n", (char *) &current_fsentry->u.device.path); // convert from pointer to char array
  529.             }
  530.  
  531.             if ((current_fsentry->header.size == 0) || (current_offset + current_fsentry->header.size >= file.size))
  532.             {
  533.                LOG_WARNING ("this IFS file is corrupted (the size of this directory entry is invalid)");
  534.                goto endofdata;
  535.             }
  536.  
  537.             current_offset += current_fsentry->header.size;
  538.          }
  539.          if (imageheader_offset + image_header->hdr_dir_size < current_offset + sizeof (current_fsentry->header))
  540.             hex_printf (&file.bytes[current_offset], imageheader_offset + image_header->hdr_dir_size - current_offset, "\n" "%zd padding bytes at offset 0x%zx (%zd):\n", imageheader_offset + image_header->hdr_dir_size - current_offset, current_offset, current_offset);
  541.          current_offset += imageheader_offset + image_header->hdr_dir_size - current_offset; // padding was processed, jump over it
  542.  
  543.          // at this point we are past the directory entries; what is stored now, up to and until the image trailer, is the files' data
  544.          if (fsentry_count > 0)
  545.          {
  546.             while (current_offset < imagetrailer_offset) // and parse data up to the trailer
  547.             {
  548.                nearest_distance = SIZE_MAX;
  549.                nearest_index = SIZE_MAX;
  550.                for (fsentry_index = 0; fsentry_index < fsentry_count; fsentry_index++)
  551.                   if (S_ISREG (fsentries[fsentry_index]->header.mode) // if this directory entry a file (i.e. it has a data blob)...
  552.                       && (imageheader_offset + (size_t) fsentries[fsentry_index]->u.file.offset >= current_offset) // ... AND its data blob is still ahead of our current pointer ...
  553.                       && (imageheader_offset + (size_t) fsentries[fsentry_index]->u.file.offset - current_offset < nearest_distance)) // ... AND it's the closest to us we've found so far
  554.                   {
  555.                      nearest_distance = imageheader_offset + (size_t) fsentries[fsentry_index]->u.file.offset - current_offset; // then remember it
  556.                      nearest_index = fsentry_index;
  557.                   }
  558.                if (nearest_index == SIZE_MAX)
  559.                   break; // found no file ahead, which means we've parsed the whole file data area, so stop the loop so as to proceed to the image trailer
  560.  
  561.                fsentry_index = nearest_index;
  562.                current_fsentry = fsentries[fsentry_index]; // quick access to closest fsentry
  563.  
  564.                // there may be padding before the file data
  565.                if (imageheader_offset + (size_t) current_fsentry->u.file.offset - current_offset > 0)
  566.                   hex_printf (&file.bytes[current_offset], imageheader_offset + (size_t) current_fsentry->u.file.offset - current_offset, "\n" "%zd padding bytes at offset 0x%zx (%zd):\n", imageheader_offset + (size_t) current_fsentry->u.file.offset - current_offset, current_offset, current_offset);
  567.                current_offset += imageheader_offset + (size_t) current_fsentry->u.file.offset - current_offset; // padding was processed, jump over it
  568.  
  569.                printf ("\n");
  570.                printf ("File data blob at offset 0x%zx (%zd):\n", current_offset, current_offset);
  571.                printf ("   corresponding dirent index: %zd/%zd\n", fsentry_index, fsentry_count);
  572.                printf ("   corresponding inode 0x%08x (%d) -%s%s%s%s\n", current_fsentry->header.ino, current_fsentry->header.ino, (current_fsentry->header.ino & 0xE0000000 ? "" : " nothing special"), (current_fsentry->header.ino & IFS_INO_PROCESSED_ELF ? " PROCESSED_ELF" : ""), (current_fsentry->header.ino & IFS_INO_RUNONCE_ELF ? " RUNONCE_ELF" : ""), (current_fsentry->header.ino & IFS_INO_BOOTSTRAP_EXE ? " BOOTSTRAP_EXE" : ""));
  573.                printf ("   corresponding path: \"%s\"\n", (char *) &current_fsentry->u.file.path); // convert from pointer to char array
  574.                printf ("   size 0x%zx (%zd) bytes\n", (size_t) current_fsentry->u.file.size, (size_t) current_fsentry->u.file.size);
  575.                if (current_offset + 4 < file.size)
  576.                   hex_printf (&file.bytes[current_offset], current_fsentry->u.file.size, "   data:\n");
  577.                if (current_offset + current_fsentry->u.file.size < file.size)
  578.                   printf ("   checksum %d\n", update_checksum (&file.bytes[current_offset], current_fsentry->u.file.size, is_foreign_endianness));
  579.                else
  580.                {
  581.                   LOG_WARNING ("this IFS file is corrupted (the size of this file data extends past the IFS size)");
  582.                   goto endofdata;
  583.                }
  584.  
  585.                current_offset += current_fsentry->u.file.size; // now jump over this file's data
  586.             }
  587.          }
  588.  
  589.          // ad this point we're past the last file data, there may be padding before the image trailer
  590.          if (imagetrailer_offset - current_offset > 0)
  591.             hex_printf (&file.bytes[current_offset], imagetrailer_offset - current_offset, "\n" "%zd padding bytes at offset %zx (%zd):\n", imagetrailer_offset - current_offset, current_offset, current_offset);
  592.          current_offset += imagetrailer_offset - current_offset; // padding was processed, jump over it
  593.  
  594.          printf ("\n");
  595.          printf ("Image trailer at offset 0x%zx (%zd) - version %d:\n", current_offset, current_offset, (image_header->flags & IMAGE_FLAGS_TRAILER_V2 ? 2 : 1));
  596.          if (image_header->flags & IMAGE_FLAGS_TRAILER_V2)
  597.          {
  598.             for (byte_index = 0; byte_index < SHA512_DIGEST_LENGTH; byte_index++)
  599.                sprintf_s (&recorded_sha512[2 * byte_index], 3, "%02x", image_trailer_v2->sha512[byte_index]);
  600.             strcpy_s (computed_sha512, sizeof (computed_sha512), SHA512 (image_header, imagetrailer_offset - imageheader_offset, NULL));
  601.             recorded_checksum = image_trailer_v2->cksum;
  602.             computed_checksum = update_checksum (image_header, imagetrailer_offset + SHA512_DIGEST_LENGTH - imageheader_offset, is_foreign_endianness);
  603.             printf ("    sha512([0x%zx-0x%zx[) = %s - %s\n", imageheader_offset, imagetrailer_offset, recorded_sha512, (strcasecmp (computed_sha512, recorded_sha512) == 0 ? "GOOD" : "BAD"));
  604.             printf ("    cksum([0x%zx-0x%zx[) = 0x%08x - %s\n", imageheader_offset, imagetrailer_offset + SHA512_DIGEST_LENGTH, recorded_checksum, (computed_checksum == recorded_checksum ? "GOOD" : "BAD"));
  605.             if (strcasecmp (computed_sha512, recorded_sha512) != 0)
  606.                printf ("Computed SHA-512: %s\n", computed_sha512);
  607.             if (computed_checksum != recorded_checksum)
  608.                printf ("Computed cksum: 0x%08x\n", computed_checksum);
  609.          }
  610.          else // old v1 trailer
  611.          {
  612.             recorded_checksum = image_trailer_v1->cksum;
  613.             computed_checksum = update_checksum (image_header, image_header->image_size - sizeof (image_trailer_v1_t), is_foreign_endianness);
  614.             printf ("    cksum([0x%zx-0x%zx[) = 0x%08x - %s\n", imageheader_offset, imagetrailer_offset, recorded_checksum, (computed_checksum == recorded_checksum ? "GOOD" : "BAD"));
  615.             if (computed_checksum != recorded_checksum)
  616.                printf ("Computed cksum: 0x%08x\n", computed_checksum);
  617.          }
  618.  
  619.          current_offset += (image_header->flags & IMAGE_FLAGS_TRAILER_V2 ? sizeof (image_trailer_v2_t) : sizeof (image_trailer_v1_t)); // now reach the next segment (typically end of file)
  620.       }
  621.  
  622.       // else it has to be a boot blob, of which we don't know the size, except that it has to fit in 0xffff bytes and be immediately followed by a startup header
  623.       else
  624.       {
  625.          // so scan for the first startup header magic and version (which makes us 6 bytes to scan for, i.e. "\xeb\x7e\xff\x00" for the magic and "\x01\x00" (LSB) for the version 1)
  626.          for (byte_index = current_offset; byte_index < file.size - 6; byte_index++)
  627.             if (memcmp (&file.bytes[byte_index], "\xeb\x7e\xff\x00" "\x01\x00", 4 + 2) == 0)
  628.                break; // stop as soon as we find it
  629.  
  630.          if (byte_index >= file.size - 6)
  631.             break; // if not found, stop scanning
  632.  
  633.          bootfile_blobsize = byte_index - current_offset;
  634.          printf ("Boot blob at offset 0x%zx (%zd):\n", current_offset, current_offset);
  635.          printf ("   size 0x%zx (%zd) bytes\n", bootfile_blobsize, bootfile_blobsize);
  636.          printf ("   checksum 0x%08x\n", update_checksum (&file.bytes[current_offset], bootfile_blobsize, false)); // NOTE: endianness is not known yet -- assume same
  637.  
  638.          current_offset = byte_index; // now reach the next segment
  639.       }
  640.    }
  641.  
  642. endofdata:
  643.    // at this point there's nothing left we're able to parse
  644.    if (current_offset < file.size)
  645.    {
  646.       printf ("End of identifiable data reached.\n");
  647.       hex_printf (&file.bytes[current_offset], file.size - current_offset, "\n" "%zd extra bytes at offset %zx (%zd):\n", file.size - current_offset, current_offset, current_offset);
  648.    }
  649.  
  650.    printf ("End of file reached at offset 0x%zx (%zd)\n", file.size, file.size);
  651.    printf ("IFS dissecation complete.\n");
  652.    return (0);
  653. }
  654.  
  655.  
  656. int dump_ifs_contents (const char *ifs_pathname, const char *outdir)
  657. {
  658.    static char outfile_pathname[MAXPATHLEN] = "";
  659.  
  660.    startup_header_t *startup_header = NULL;
  661.    size_t startupheader_offset = 0;
  662.    image_header_t *image_header = NULL;
  663.    size_t imageheader_offset = 0;
  664.    size_t imagetrailer_offset = 0;
  665.    fsentry_t **fsentries = NULL; // mallocated
  666.    size_t fsentry_count = 0;
  667.    fsentry_t *current_fsentry = NULL;
  668.    buffer_t decompression_dst;
  669.    size_t startupfile_blobsize = 0;
  670.    size_t compressed_blocksize;
  671.    struct utimbuf file_times = { 0, 0 };
  672.    void *reallocated_ptr;
  673.    uint8_t *decompressor_out;
  674.    uint8_t *decompressor_in;
  675.    size_t decompressor_outlen;
  676.    size_t bootfile_blobsize = 0;
  677.    size_t current_offset;
  678.    size_t fsentry_index;
  679.    size_t nearest_distance;
  680.    size_t nearest_index;
  681.    size_t byte_index;
  682.    buffer_t file;
  683.    FILE *fp;
  684.    int cf;
  685.  
  686.    // open and read IFS file
  687.    if (!Buffer_ReadFromFile (&file, ifs_pathname))
  688.       DIE_WITH_EXITCODE (1, "can't open \"%s\" for reading: %s\n", ifs_pathname, strerror (errno));
  689.  
  690.    // create the output directory
  691.    create_intermediate_dirs (outdir);
  692.    (void) mkdir (outdir, 0755);
  693.  
  694.    // parse file from start to end
  695.    current_offset = 0;
  696.    for (;;)
  697.    {
  698.       // does a startup header start here ?
  699.       if ((current_offset + sizeof (startup_header_t) < file.size)
  700.           && (startup_header == NULL)
  701.           && (memcmp (&file.bytes[current_offset], "\xeb\x7e\xff\x00", 4) == 0))
  702.       {
  703.          startupheader_offset = current_offset;
  704.          startup_header = (startup_header_t *) &file.bytes[startupheader_offset];
  705.  
  706.          // layout:
  707.          // [STARTUP HEADER]
  708.          // (startup file blob)
  709.          // [STARTUP TRAILER v1 or v2]
  710.  
  711.          // validate that the file can contain up to the startup trailer
  712.          if (current_offset + startup_header->startup_size > file.size)
  713.          {
  714.             LOG_WARNING ("this IFS file is corrupted (startup trailer extends past end of file)");
  715.             goto endofdata;
  716.          }
  717.  
  718.          // take note of the image compression flags
  719.          cf = startup_header->flags1 & STARTUP_HDR_FLAGS1_COMPRESS_MASK;
  720.  
  721.          // locate the right startup trailer at the right offset
  722.          if (startup_header->flags1 & STARTUP_HDR_FLAGS1_TRAILER_V2)
  723.             startupfile_blobsize = startup_header->startup_size - sizeof (startup_header_t) - sizeof (startup_trailer_v2_t);
  724.          else // old V1 trailer
  725.             startupfile_blobsize = startup_header->startup_size - sizeof (startup_header_t) - sizeof (startup_trailer_v1_t);
  726.  
  727.          current_offset += sizeof (startup_header_t); // jump over the startup header and reach the startup blob
  728.  
  729.          // write startup blob
  730.          sprintf_s (outfile_pathname, sizeof (outfile_pathname), "%s/startup.bin", outdir);
  731.          fopen_s (&fp, outfile_pathname, "wb");
  732.          ASSERT (fp, "failed to open '%s': %s", outfile_pathname, strerror (errno));
  733.          fwrite (&file.bytes[current_offset], 1, startupfile_blobsize, fp);
  734.          fclose (fp);
  735.  
  736.          current_offset += startupfile_blobsize; // jump over the startup blob and reach the startup trailer
  737.          current_offset += (startup_header->flags1 & STARTUP_HDR_FLAGS1_TRAILER_V2 ? sizeof (startup_trailer_v2_t) : sizeof (startup_trailer_v1_t)); // jump over the startup trailer and reach the next segment
  738.       }
  739.  
  740.       // else does an image header start here ?
  741.       else if ((current_offset + sizeof (image_header_t) < file.size)
  742.                && (image_header == NULL)
  743.                && (((cf == STARTUP_HDR_FLAGS1_COMPRESS_NONE) && (memcmp (&file.bytes[current_offset], "imagefs", 7) == 0))
  744.                || (cf != STARTUP_HDR_FLAGS1_COMPRESS_NONE) && (startup_header->imagefs_size > 0)))
  745.       {
  746.          imageheader_offset = current_offset;
  747.          image_header = (image_header_t *) &file.bytes[imageheader_offset];
  748.  
  749.          // should we decompress it ?
  750.          if (cf != STARTUP_HDR_FLAGS1_COMPRESS_NONE)
  751.          {
  752.             // it appears mkifs compresses data in blocks, prefixed by 2-byte block size in BIG ENDIAN
  753.             Buffer_InitWithSize (&decompression_dst, startup_header->imagefs_size * 11 / 10); // mallocate and add 10% for safety
  754.             decompression_dst.size = 0;
  755.  
  756.             if (cf == STARTUP_HDR_FLAGS1_COMPRESS_UCL)
  757.                ASSERT (ucl_init () == UCL_E_OK, "UCL library initialization failed -- please recompile this tool with less aggressive optimizations");
  758.             else if (cf == STARTUP_HDR_FLAGS1_COMPRESS_LZO)
  759.                ASSERT (lzo_init () == LZO_E_OK, "LZO library initialization failed -- please recompile this tool with less aggressive optimizations");
  760.             else if (cf == STARTUP_HDR_FLAGS1_COMPRESS_ZLIB)
  761.             {
  762.                LOG_WARNING ("unimplemented compression scheme: zlib (FIXME)");
  763.                goto endofdata;
  764.             }
  765.             else
  766.             {
  767.                LOG_WARNING ("unsupported compression flags: 0x%2x", cf);
  768.                goto endofdata;
  769.             }
  770.  
  771.             // run the compressed payload (the imagefs) through the right decompression algorithm
  772.             for (;;)
  773.             {
  774.                compressed_blocksize = (file.bytes[current_offset + 0] << 8) | (file.bytes[current_offset + 1] << 0); // read block size word (in big engian)
  775.                current_offset += 2; // skip it
  776.                if (compressed_blocksize == 0)
  777.                   break; // a nil block size means end of stream is reached
  778.                LOG_DEBUG ("about to decompress block of %zd bytes", compressed_blocksize);
  779.                decompressor_in = &file.bytes[current_offset];
  780.                decompressor_out = &decompression_dst.bytes[decompression_dst.size];
  781.                decompressor_outlen = 0;
  782.  
  783.                if (cf == STARTUP_HDR_FLAGS1_COMPRESS_UCL)
  784.                {
  785.                   // UCL compression. NOTE: the decompressor function used in startup-x86 is "ucl_nrv2b_decompress_8 / ucl_nrv2b_decompress_le16 / ucl_nrv2b_decompress_le32"
  786.                   static ucl_uint ucl_outlen; // have a different variable because of pointer size mismatch
  787.                   if (ucl_nrv2b_decompress_8 (decompressor_in, (ucl_uint) compressed_blocksize, decompressor_out, &ucl_outlen, NULL) != UCL_E_OK)
  788.                   {
  789.                      LOG_WARNING ("this IFS file is corrupted (UCL decompression failed)");
  790.                      goto endofdata;
  791.                   }
  792.                   decompressor_outlen = ucl_outlen;
  793.                }
  794.                else if (cf == STARTUP_HDR_FLAGS1_COMPRESS_LZO)
  795.                {
  796.                   // LZO decompression. NOTE: mkifs uses the full LZO package, whereas I use minilzo.
  797.                   static lzo_uint lzo_outlen; // have a different variable because of pointer size mismatch
  798.                   if (lzo1x_decompress (decompressor_in, (lzo_uint) compressed_blocksize, decompressor_out, &lzo_outlen, NULL) != LZO_E_OK)
  799.                   {
  800.                      LOG_WARNING ("this IFS file is corrupted (UCL decompression failed)");
  801.                      goto endofdata;
  802.                   }
  803.                   decompressor_outlen = lzo_outlen;
  804.                }
  805.                else if (cf == STARTUP_HDR_FLAGS1_COMPRESS_ZLIB)
  806.                   ; // TODO
  807.  
  808.                current_offset += compressed_blocksize;
  809.                decompression_dst.size += decompressor_outlen;
  810.             }
  811.  
  812.             LOG_INFO ("decompressed %zd bytes into %zd bytes\n", file.size - imageheader_offset, decompression_dst.size);
  813.  
  814.             // now place the decompressed buffer in the payload at the imagefs offset
  815.             ASSERT_WITH_ERRNO (Buffer_WriteBufferAt (&file, imageheader_offset, &decompression_dst));
  816.             current_offset = imageheader_offset; // jump back to where we put the uncompressed data
  817.             file.size = imageheader_offset + decompression_dst.size; // update IFS data size
  818.  
  819.             startup_header = (startup_header_t *) &file.bytes[startupheader_offset]; // fix the pointers that might have changed
  820.             image_header = (image_header_t *) &file.bytes[imageheader_offset]; // fix the pointers that might have changed
  821.          }
  822.  
  823.          // layout:
  824.          // [IMAGE HEADER]
  825.          // [image directory entries]
  826.          // [smallest file blobs up to KERNEL]
  827.          // [padding]
  828.          // [KERNEL]
  829.          // [rest of file blobs]
  830.          // [IMAGE FOOTER]
  831.  
  832.          // validate that the file can contain up to the image trailer
  833.          if (current_offset + image_header->image_size > file.size)
  834.          {
  835.             LOG_WARNING ("this IFS file is corrupted (image trailer extends past end of file)");
  836.             goto endofdata;
  837.          }
  838.  
  839.          // locate the image trailer at the right offset
  840.          if (image_header->flags & IMAGE_FLAGS_TRAILER_V2)
  841.             imagetrailer_offset = current_offset + image_header->image_size - sizeof (image_trailer_v2_t);
  842.          else // old V1 trailer
  843.             imagetrailer_offset = current_offset + image_header->image_size - sizeof (image_trailer_v1_t);
  844.  
  845.          current_offset += sizeof (image_header_t); // jump over the image header
  846.          current_offset += image_header->dir_offset - sizeof (image_header_t); // jump over possible padding
  847.  
  848.          // dump all directory entries until the last one included
  849.          fsentries = NULL;
  850.          fsentry_count = 0;
  851.          while (current_offset < imageheader_offset + image_header->hdr_dir_size)
  852.          {
  853.             current_fsentry = (fsentry_t *) &file.bytes[current_offset];
  854.  
  855.             if (imageheader_offset + image_header->hdr_dir_size - current_offset < sizeof (current_fsentry->header))
  856.                break; // end padding reached
  857.  
  858.             // stack up the filesystem entry pointers in an array while we read them
  859.             reallocated_ptr = realloc (fsentries, (fsentry_count + 1) * sizeof (fsentry_t *));
  860.             ASSERT_WITH_ERRNO (reallocated_ptr);
  861.             fsentries = reallocated_ptr;
  862.             fsentries[fsentry_count] = current_fsentry;
  863.             fsentry_count++;
  864.  
  865.             if ((current_fsentry->header.size == 0) || (current_offset + current_fsentry->header.size >= file.size))
  866.             {
  867.                LOG_WARNING ("this IFS file is corrupted (the size of this directory entry is invalid)");
  868.                goto endofdata;
  869.             }
  870.  
  871.             current_offset += current_fsentry->header.size;
  872.          }
  873.          current_offset += imageheader_offset + image_header->hdr_dir_size - current_offset; // jump over possible padding
  874.  
  875.          // at this point we are past the directory entries; what is stored now, up to and until the image trailer, is the files' data
  876.          if (fsentry_count > 0)
  877.          {
  878.             while (current_offset < imagetrailer_offset) // and parse data up to the trailer
  879.             {
  880.                nearest_distance = SIZE_MAX;
  881.                nearest_index = SIZE_MAX;
  882.                for (fsentry_index = 0; fsentry_index < fsentry_count; fsentry_index++)
  883.                   if (S_ISREG (fsentries[fsentry_index]->header.mode) // if this directory entry a file (i.e. it has a data blob)...
  884.                       && (imageheader_offset + (size_t) fsentries[fsentry_index]->u.file.offset >= current_offset) // ... AND its data blob is still ahead of our current pointer ...
  885.                       && (imageheader_offset + (size_t) fsentries[fsentry_index]->u.file.offset - current_offset < nearest_distance)) // ... AND it's the closest to us we've found so far
  886.                   {
  887.                      nearest_distance = imageheader_offset + (size_t) fsentries[fsentry_index]->u.file.offset - current_offset; // then remember it
  888.                      nearest_index = fsentry_index;
  889.                   }
  890.                if (nearest_index == SIZE_MAX)
  891.                   break; // found no file ahead, which means we've parsed the whole file data area, so stop the loop so as to proceed to the image trailer
  892.  
  893.                fsentry_index = nearest_index;
  894.                current_fsentry = fsentries[fsentry_index]; // quick access to closest fsentry
  895.  
  896.                current_offset += imageheader_offset + (size_t) current_fsentry->u.file.offset - current_offset; // jump over possible padding
  897.  
  898.                if (current_offset + current_fsentry->u.file.size >= file.size)
  899.                {
  900.                   LOG_WARNING ("this IFS file is corrupted (the size of this file data extends past the IFS size)");
  901.                   goto endofdata;
  902.                }
  903.  
  904.                // write filesystem data entry
  905.                if (S_ISDIR (current_fsentry->header.mode))
  906.                {
  907.                   sprintf_s (outfile_pathname, sizeof (outfile_pathname), "%s/%s", outdir, (char *) &current_fsentry->u.dir.path); // convert from pointer to char array
  908.                   create_intermediate_dirs (outfile_pathname);
  909.                   (void) mkdir (outfile_pathname, current_fsentry->header.mode & 0777);
  910.                }
  911.                else if (S_ISLNK (current_fsentry->header.mode))
  912.                {
  913.                   sprintf_s (outfile_pathname, sizeof (outfile_pathname), "%s/%s", outdir, (char *) &current_fsentry->u.symlink.path); // convert from pointer to char array
  914.                   create_intermediate_dirs (outfile_pathname);
  915. #ifdef _WIN32
  916.                   fopen_s (&fp, outfile_pathname, "wb"); // on Windows create symlinks as plain files
  917.                   ASSERT (fp, "failed to open '%s': %s", outfile_pathname, strerror (errno));
  918.                   fwrite ((char *) &current_fsentry->u.symlink.path + current_fsentry->u.symlink.sym_offset, 1, current_fsentry->u.symlink.sym_size, fp); // convert from pointer to char array
  919.                   fclose (fp);
  920. #else // !_WIN32, thus POSIX
  921.                   symlink (current_fsentry->u.symlink.contents, outfile_pathname); // on UNIX systems, just create the symlink for real
  922. #endif // _WIN32
  923.                }
  924.                else if (S_ISREG (current_fsentry->header.mode))
  925.                {
  926.                   sprintf_s (outfile_pathname, sizeof (outfile_pathname), "%s/%s", outdir, (char *) &current_fsentry->u.file.path); // convert from pointer to char array
  927.                   create_intermediate_dirs (outfile_pathname);
  928.                   fopen_s (&fp, outfile_pathname, "wb"); // on Windows create symlinks as plain files
  929.                   ASSERT (fp, "failed to open '%s': %s", outfile_pathname, strerror (errno));
  930.                   fwrite (&file.bytes[current_offset], 1, current_fsentry->u.file.size, fp);
  931.                   fclose (fp);
  932.                }
  933.                else // must be a device node. Since we might not be the super-user and/or on Win32, create plain file with "X:Y" as data
  934.                {
  935.                   sprintf_s (outfile_pathname, sizeof (outfile_pathname), "%s/%s", outdir, (char *) &current_fsentry->u.device.path); // convert from pointer to char array
  936.                   create_intermediate_dirs (outfile_pathname);
  937.                   fopen_s (&fp, outfile_pathname, "wb"); // on Windows create symlinks as plain files
  938.                   ASSERT (fp, "failed to open '%s': %s", outfile_pathname, strerror (errno));
  939.                   fprintf (fp, "%u:%u", current_fsentry->u.device.dev, current_fsentry->u.device.rdev);
  940.                   fclose (fp);
  941.                }
  942.  
  943.                // set created file mtime
  944.                file_times.actime = current_fsentry->header.mtime;
  945.                file_times.modtime = current_fsentry->header.mtime;
  946.                utime (outfile_pathname, &file_times);
  947.  
  948.                // set created file mode
  949. #ifndef _WIN32
  950.                (void) chmod (outfile_pathname, current_fsentry->header.mode & 0777); // only on POSIX systems
  951. #endif // !_WIN32
  952.  
  953.                current_offset += current_fsentry->u.file.size; // now jump over this file's data
  954.             }
  955.          }
  956.  
  957.          // ad this point we're past the last file data, there may be padding before the image trailer
  958.          current_offset += imagetrailer_offset - current_offset; // jump over possible padding and reach the image trailer
  959.          current_offset += (image_header->flags & IMAGE_FLAGS_TRAILER_V2 ? sizeof (image_trailer_v2_t) : sizeof (image_trailer_v1_t)); // now jump over the image trailer and reach the next segment (typically end of file)
  960.       }
  961.  
  962.       // else it has to be a boot blob, of which we don't know the size, except that it has to fit in 0xffff bytes and be immediately followed by a startup header
  963.       else
  964.       {
  965.          // so scan for the first startup header magic and version (which makes us 6 bytes to scan for, i.e. "\xeb\x7e\xff\x00" for the magic and "\x01\x00" (LSB) for the version 1)
  966.          for (byte_index = current_offset; byte_index < file.size - 6; byte_index++)
  967.             if (memcmp (&file.bytes[byte_index], "\xeb\x7e\xff\x00" "\x01\x00", 4 + 2) == 0)
  968.                break; // stop as soon as we find it
  969.  
  970.          if (byte_index >= file.size - 6)
  971.             break; // if not found, stop scanning
  972.  
  973.          bootfile_blobsize = byte_index - current_offset;
  974.  
  975.          // write boot blob
  976.          sprintf_s (outfile_pathname, sizeof (outfile_pathname), "%s/boot.bin", outdir);
  977.          fopen_s (&fp, outfile_pathname, "wb");
  978.          ASSERT (fp, "failed to open '%s': %s", outfile_pathname, strerror (errno));
  979.          fwrite (&file.bytes[current_offset], 1, bootfile_blobsize, fp);
  980.          fclose (fp);
  981.  
  982.          current_offset = byte_index; // now reach the next segment
  983.       }
  984.    }
  985.  
  986. endofdata:
  987.    return (0);
  988. }
  989.  
  990.  
  991. int dump_file_hex (const char *pathname)
  992. {
  993.    buffer_t file;
  994.  
  995.    ASSERT_WITH_ERRNO (Buffer_ReadFromFile (&file, pathname));
  996.    hex_fprintf (stdout, file.bytes, file.size, 16, "%s (%zd bytes):\n", pathname, file.size);
  997.    return (0);
  998. }
  999.