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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.    char *executable_format = NULL;
  206.    size_t startupfile_blobsize = 0;
  207.    size_t compressed_blocksize;
  208.    void *reallocated_ptr;
  209.    bool is_foreign_endianness;
  210.    uint8_t *decompressor_out;
  211.    uint8_t *decompressor_in;
  212.    size_t decompressor_outlen;
  213.    size_t bootfile_blobsize = 0;
  214.    size_t current_offset;
  215.    size_t fsentry_index;
  216.    size_t nearest_distance;
  217.    size_t nearest_index;
  218.    size_t byte_index;
  219.    uint32_t recorded_checksum;
  220.    uint32_t computed_checksum;
  221.    buffer_t file;
  222.    time_t mtime;
  223.    int cf;
  224.  
  225.    // open and read IFS file
  226.    if (!Buffer_ReadFromFile (&file, ifs_pathname))
  227.       DIE_WITH_EXITCODE (1, "can't open \"%s\" for reading: %s", ifs_pathname, strerror (errno));
  228.  
  229.    printf ("QNX In-kernel Filesystem analysis produced by ifstool version " VERSION_FMT_YYYYMMDD "\n", VERSION_ARG_YYYYMMDD);
  230.    if (hide_filename)
  231.       printf ("IFS file - size 0x%zx (%zd) bytes\n", file.size, file.size);
  232.    else
  233.       printf ("IFS file \"%s\" - size 0x%zx (%zd) bytes\n", ifs_pathname, file.size, file.size);
  234.  
  235.    // parse file from start to end
  236.    current_offset = 0;
  237.    cf = STARTUP_HDR_FLAGS1_COMPRESS_NONE;
  238.    for (;;)
  239.    {
  240.       // does a startup header start here ?
  241.       if ((current_offset + sizeof (startup_header_t) < file.size)
  242.           && (startup_header == NULL)
  243.           && (memcmp (&file.bytes[current_offset], "\xeb\x7e\xff\x00", 4) == 0))
  244.       {
  245.          startupheader_offset = current_offset;
  246.          startup_header = (startup_header_t *) &file.bytes[startupheader_offset];
  247.  
  248.          // layout:
  249.          // [STARTUP HEADER]
  250.          // (startup file blob)
  251.          // [STARTUP TRAILER v1 or v2]
  252.  
  253.          printf ("\n");
  254.          printf ("Startup header at offset 0x%zx (%zd):\n", current_offset, current_offset);
  255.          printf ("   signature     = %02x %02x %02x %02x - good\n", startup_header->signature[0], startup_header->signature[1], startup_header->signature[2], startup_header->signature[3]);
  256.          printf ("   version       = 0x%04x (%d) - %s\n", startup_header->version, startup_header->version, (startup_header->version == 1 ? "looks good" : "???"));
  257.          cf = startup_header->flags1 & STARTUP_HDR_FLAGS1_COMPRESS_MASK;
  258.          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)")))));
  259.          printf ("   flags2        = 0x%02x (%s) - %s\n", startup_header->flags2, BINARY (startup_header->flags2), (startup_header->flags2 == 0 ? "looks good" : "???"));
  260.          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"));
  261.          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")));
  262.          printf ("   startup_vaddr = 0x%08x (%d) - virtual address to transfer to after IPL is done\n", startup_header->startup_vaddr, startup_header->startup_vaddr);
  263.          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);
  264.          printf ("   image_paddr   = 0x%08x (%d) - physical address of image\n", startup_header->image_paddr, startup_header->image_paddr);
  265.          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);
  266.          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);
  267.          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)"));
  268.          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" : "???"));
  269.          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"));
  270.          printf ("   imagefs_size  = 0x%08x (%d) - size of uncompressed imagefs\n", startup_header->imagefs_size, startup_header->imagefs_size);
  271.          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" : "???"));
  272.          printf ("   zero0         = 0x%04x (%d) - zeros - %s\n", startup_header->zero0, startup_header->zero0, (startup_header->zero0 == 0 ? "looks good" : "??? should be zero"));
  273.          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"));
  274.          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"));
  275.          hex_printf ((uint8_t *) &startup_header->info[0], sizeof (startup_header->info), "   info[48] =\n");
  276.  
  277.          // validate that the file can contain up to the startup trailer
  278.          if (current_offset + startup_header->startup_size > file.size)
  279.          {
  280.             LOG_WARNING ("this IFS file is corrupted (startup trailer extends past end of file)");
  281.             goto endofdata;
  282.          }
  283.  
  284.          // check if this endianness is ours
  285.          if (   ( (startup_header->flags1 & STARTUP_HDR_FLAGS1_BIGENDIAN) && (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__))
  286.              || (!(startup_header->flags1 & STARTUP_HDR_FLAGS1_BIGENDIAN) && (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)))
  287.             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
  288.          else
  289.             is_foreign_endianness = false; // else this header is for the same endianness as us
  290.  
  291.          // locate the right startup trailer at the right offset
  292.          if (startup_header->flags1 & STARTUP_HDR_FLAGS1_TRAILER_V2)
  293.          {
  294.             startuptrailer_offset = current_offset + startup_header->startup_size - sizeof (startup_trailer_v2_t);
  295.             startup_trailer_v2 = (startup_trailer_v2_t *) &file.bytes[startuptrailer_offset];
  296.             startupfile_blobsize = startup_header->startup_size - sizeof (startup_header_t) - sizeof (startup_trailer_v2_t);
  297.          }
  298.          else // old V1 trailer
  299.          {
  300.             startuptrailer_offset = current_offset + startup_header->startup_size - sizeof (startup_trailer_v1_t);
  301.             startup_trailer_v1 = (startup_trailer_v1_t *) &file.bytes[startuptrailer_offset];
  302.             startupfile_blobsize = startup_header->startup_size - sizeof (startup_header_t) - sizeof (startup_trailer_v1_t);
  303.          }
  304.  
  305.          current_offset += sizeof (startup_header_t); // jump over the startup header and reach the startup blob
  306.          printf ("\n");
  307.          printf ("Startup blob at offset 0x%zx (%zd):\n", current_offset, current_offset);
  308.          printf ("   size 0x%zx (%zd) bytes\n", startupfile_blobsize, startupfile_blobsize);
  309.          printf ("   checksum 0x%08x\n", update_checksum (&file.bytes[current_offset], startupfile_blobsize, is_foreign_endianness));
  310.  
  311.          current_offset += startupfile_blobsize; // jump over the startup blob and reach the startup trailer
  312.          printf ("\n");
  313.          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));
  314.          if (startup_header->flags1 & STARTUP_HDR_FLAGS1_TRAILER_V2)
  315.          {
  316.             for (byte_index = 0; byte_index < SHA512_DIGEST_LENGTH; byte_index++)
  317.                sprintf_s (&recorded_sha512[2 * byte_index], 3, "%02x", startup_trailer_v2->sha512[byte_index]);
  318.             strcpy_s (computed_sha512, sizeof (computed_sha512), SHA512 (startup_header, startuptrailer_offset - startupheader_offset, NULL));
  319.             recorded_checksum = startup_trailer_v2->cksum;
  320.             computed_checksum = update_checksum (startup_header, startuptrailer_offset + SHA512_DIGEST_LENGTH - startupheader_offset, is_foreign_endianness);
  321.             printf ("    sha512([0x%zx-0x%zx[) = %s - %s\n", startupheader_offset, startuptrailer_offset, recorded_sha512, (strcasecmp (computed_sha512, recorded_sha512) == 0 ? "GOOD" : "BAD"));
  322.             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"));
  323.             if (strcasecmp (computed_sha512, recorded_sha512) != 0)
  324.                printf ("Computed SHA-512: %s\n", computed_sha512);
  325.             if (computed_checksum != recorded_checksum)
  326.                printf ("Computed cksum: 0x%08x\n", computed_checksum);
  327.          }
  328.          else // old v1 trailer
  329.          {
  330.             recorded_checksum = startup_trailer_v1->cksum;
  331.             computed_checksum = update_checksum (startup_header, sizeof (startup_header) + startupfile_blobsize, is_foreign_endianness);
  332.             printf ("    cksum([0x%zx-0x%zx[) = 0x%08x - %s\n", startupheader_offset, startuptrailer_offset, recorded_checksum, (computed_checksum == recorded_checksum ? "GOOD" : "BAD"));
  333.             if (computed_checksum != recorded_checksum)
  334.                printf ("Computed cksum: 0x%08x\n", computed_checksum);
  335.          }
  336.  
  337.          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
  338.       }
  339.  
  340.       // else does an image header start here ?
  341.       else if ((current_offset + sizeof (image_header_t) < file.size)
  342.                && (image_header == NULL)
  343.                && (   ((cf == STARTUP_HDR_FLAGS1_COMPRESS_NONE) && (memcmp (&file.bytes[current_offset], "imagefs", 7) == 0))
  344.                    || (cf != STARTUP_HDR_FLAGS1_COMPRESS_NONE) && (startup_header->imagefs_size > 0)))
  345.       {
  346.          imageheader_offset = current_offset;
  347.          image_header = (image_header_t *) &file.bytes[imageheader_offset];
  348.  
  349.          // should we decompress it ?
  350.          if (cf != STARTUP_HDR_FLAGS1_COMPRESS_NONE)
  351.          {
  352.             // it appears mkifs compresses data in blocks, prefixed by 2-byte block size in BIG ENDIAN
  353.             Buffer_InitWithSize (&decompression_dst, startup_header->imagefs_size * 11 / 10); // mallocate and add 10% for safety
  354.             decompression_dst.size = 0;
  355.  
  356.             if (cf == STARTUP_HDR_FLAGS1_COMPRESS_UCL)
  357.                ASSERT (ucl_init () == UCL_E_OK, "UCL library initialization failed -- please recompile this tool with less aggressive optimizations");
  358.             else if (cf == STARTUP_HDR_FLAGS1_COMPRESS_LZO)
  359.                ASSERT (lzo_init () == LZO_E_OK, "LZO library initialization failed -- please recompile this tool with less aggressive optimizations");
  360.             else if (cf == STARTUP_HDR_FLAGS1_COMPRESS_ZLIB)
  361.             {
  362.                LOG_WARNING ("unimplemented compression scheme: zlib (FIXME)");
  363.                goto endofdata;
  364.             }
  365.             else
  366.             {
  367.                LOG_WARNING ("unsupported compression flags: 0x%2x", cf);
  368.                goto endofdata;
  369.             }
  370.  
  371.             // run the compressed payload (the imagefs) through the right decompression algorithm
  372.             for (;;)
  373.             {
  374.                compressed_blocksize = (file.bytes[current_offset + 0] << 8) | (file.bytes[current_offset + 1] << 0); // read block size word (in big engian)
  375.                current_offset += 2; // skip it
  376.                if (compressed_blocksize == 0)
  377.                   break; // a nil block size means end of stream is reached
  378.                //LOG_DEBUG ("about to decompress block of %zd bytes", compressed_blocksize);
  379.                decompressor_in = &file.bytes[current_offset];
  380.                decompressor_out = &decompression_dst.bytes[decompression_dst.size];
  381.                decompressor_outlen = 0;
  382.  
  383.                if (cf == STARTUP_HDR_FLAGS1_COMPRESS_UCL)
  384.                {
  385.                   // UCL compression. NOTE: the decompressor function used in startup-x86 is "ucl_nrv2b_decompress_8 / ucl_nrv2b_decompress_le16 / ucl_nrv2b_decompress_le32"
  386.                   static ucl_uint ucl_outlen; // have a different variable because of pointer size mismatch
  387.                   if (ucl_nrv2b_decompress_8 (decompressor_in, (ucl_uint) compressed_blocksize, decompressor_out, &ucl_outlen, NULL) != UCL_E_OK)
  388.                   {
  389.                      LOG_WARNING ("this IFS file is corrupted (UCL decompression failed)");
  390.                      goto endofdata;
  391.                   }
  392.                   decompressor_outlen = ucl_outlen;
  393.                }
  394.                else if (cf == STARTUP_HDR_FLAGS1_COMPRESS_LZO)
  395.                {
  396.                   // LZO decompression. NOTE: mkifs uses the full LZO package, whereas I use minilzo.
  397.                   static lzo_uint lzo_outlen; // have a different variable because of pointer size mismatch
  398.                   if (lzo1x_decompress (decompressor_in, (lzo_uint) compressed_blocksize, decompressor_out, &lzo_outlen, NULL) != LZO_E_OK)
  399.                   {
  400.                      LOG_WARNING ("this IFS file is corrupted (UCL decompression failed)");
  401.                      goto endofdata;
  402.                   }
  403.                   decompressor_outlen = lzo_outlen;
  404.                }
  405.                else if (cf == STARTUP_HDR_FLAGS1_COMPRESS_ZLIB)
  406.                   ; // TODO
  407.  
  408.                current_offset += compressed_blocksize;
  409.                decompression_dst.size += decompressor_outlen;
  410.             }
  411.  
  412.             LOG_INFO ("decompressed %zd bytes into %zd bytes\n", file.size - imageheader_offset, decompression_dst.size);
  413.  
  414.             // now place the decompressed buffer in the payload at the imagefs offset
  415.             ASSERT_WITH_ERRNO (Buffer_WriteBufferAt (&file, imageheader_offset, &decompression_dst));
  416.             current_offset = imageheader_offset; // jump back to where we put the uncompressed data
  417.             file.size = imageheader_offset + decompression_dst.size; // update IFS data size
  418.  
  419.             startup_header = (startup_header_t *) &file.bytes[startupheader_offset]; // fix the pointers that might have changed
  420.             if (startup_header->flags1 & STARTUP_HDR_FLAGS1_TRAILER_V2)
  421.                startup_trailer_v2 = (startup_trailer_v2_t *) &file.bytes[startuptrailer_offset];
  422.             else // old V1 trailer
  423.                startup_trailer_v1 = (startup_trailer_v1_t *) &file.bytes[startuptrailer_offset];
  424.             image_header = (image_header_t *) &file.bytes[imageheader_offset]; // fix the pointers that might have changed
  425.          }
  426.  
  427.          // layout:
  428.          // [IMAGE HEADER]
  429.          // [image directory entries]
  430.          // [smallest file blobs up to KERNEL]
  431.          // [padding]
  432.          // [KERNEL]
  433.          // [rest of file blobs]
  434.          // [IMAGE FOOTER]
  435.  
  436.          printf ("\n");
  437.          printf ("Image header at offset %zx (%zd):\n", current_offset, current_offset);
  438.          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);
  439.          printf ("   flags        = 0x%02x (%s)\n", image_header->flags, describe_uint8 (image_header->flags, imageheader_flags_strings));
  440.          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)"));
  441.          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)"));
  442.          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")));
  443.          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]);
  444.          printf ("   script_ino   = 0x%08x (%d) - inode of compiled bootscript\n", image_header->script_ino, image_header->script_ino);
  445.          printf ("   chain_paddr  = 0x%08x (%d) - offset to next fs signature\n", image_header->chain_paddr, image_header->chain_paddr);
  446.          hex_printf ((uint8_t *) &image_header->spare[0], sizeof (image_header->spare), "   spare[10] =\n");
  447.          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]));
  448.          printf ("   mountpoint   = \"%s\"\n", image_header->mountpoint);
  449.  
  450.          // validate that the file can contain up to the image trailer
  451.          if (current_offset + image_header->image_size > file.size)
  452.          {
  453.             LOG_WARNING ("this IFS file is corrupted (image trailer extends past end of file)");
  454.             goto endofdata;
  455.          }
  456.  
  457.          // check if this endianness is ours
  458.          if (   ( (image_header->flags & IMAGE_FLAGS_BIGENDIAN) && (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__))
  459.              || (!(image_header->flags & IMAGE_FLAGS_BIGENDIAN) && (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)))
  460.             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
  461.          else
  462.             is_foreign_endianness = false; // else this header is for the same endianness as us
  463.  
  464.          // locate the image trailer at the right offset
  465.          if (image_header->flags & IMAGE_FLAGS_TRAILER_V2)
  466.          {
  467.             imagetrailer_offset = current_offset + image_header->image_size - sizeof (image_trailer_v2_t);
  468.             image_trailer_v2 = (image_trailer_v2_t *) &file.bytes[imagetrailer_offset];
  469.          }
  470.          else // old V1 trailer
  471.          {
  472.             imagetrailer_offset = current_offset + image_header->image_size - sizeof (image_trailer_v1_t);
  473.             image_trailer_v1 = (image_trailer_v1_t *) &file.bytes[imagetrailer_offset];
  474.          }
  475.  
  476.          current_offset += sizeof (image_header_t); // jump over the image header and reach the first directory entry
  477.  
  478.          // there may be padding before the first directory entry
  479.          if (image_header->dir_offset - sizeof (image_header_t) > 0)
  480.             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);
  481.          current_offset += image_header->dir_offset - sizeof (image_header_t); // padding was processed, jump over it
  482.  
  483.          // dump all directory entries until the last one included
  484.          fsentries = NULL;
  485.          fsentry_count = 0;
  486.          while (current_offset < imageheader_offset + image_header->hdr_dir_size)
  487.          {
  488.             current_fsentry = (fsentry_t *) &file.bytes[current_offset];
  489.  
  490.             if (imageheader_offset + image_header->hdr_dir_size - current_offset < sizeof (current_fsentry->header))
  491.                break; // end padding reached
  492.  
  493.             // stack up the filesystem entry pointers in an array while we read them
  494.             reallocated_ptr = realloc (fsentries, (fsentry_count + 1) * sizeof (fsentry_t *));
  495.             ASSERT_WITH_ERRNO (reallocated_ptr);
  496.             fsentries = reallocated_ptr;
  497.             fsentries[fsentry_count] = current_fsentry;
  498.             fsentry_count++;
  499.  
  500.             printf ("\n");
  501.             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);
  502.             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"));
  503.             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"));
  504.             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" : ""));
  505.             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);
  506.             printf ("   gid            = 0x%08x (%d) - owner group ID%s\n", current_fsentry->header.gid, current_fsentry->header.gid, (current_fsentry->header.gid == 0 ? " (root)" : ""));
  507.             printf ("   uid            = 0x%08x (%d) - owner user ID%s\n", current_fsentry->header.uid, current_fsentry->header.uid, (current_fsentry->header.uid == 0 ? " (root)" : ""));
  508.             mtime = (time_t) current_fsentry->header.mtime;
  509.             printf ("   mtime          = 0x%08x (%d) - POSIX timestamp: %s", current_fsentry->header.mtime, current_fsentry->header.mtime, asctime (localtime (&mtime))); // NOTE: asctime() provides the newline
  510.             if (S_ISDIR (current_fsentry->header.mode))
  511.                printf ("   [DIRECTORY] path = \"%s\"\n", (char *) &current_fsentry->u.dir.path); // convert from pointer to char array
  512.             else if (S_ISREG (current_fsentry->header.mode))
  513.             {
  514.                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)"));
  515.                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)"));
  516.                printf ("   [FILE] path   = \"%s\"\n", (char *) &current_fsentry->u.file.path); // convert from pointer to char array
  517.             }
  518.             else if (S_ISLNK (current_fsentry->header.mode))
  519.             {
  520.                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)"));
  521.                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)"));
  522.                printf ("   [SYMLINK] path       = \"%s\"\n", (char *) &current_fsentry->u.symlink.path); // convert from pointer to char array
  523.                printf ("   [SYMLINK] contents   = \"%s\"\n", ((char *) &current_fsentry->u.symlink.path) + current_fsentry->u.symlink.sym_offset); // convert from pointer to char array
  524.             }
  525.             else // can only be a device
  526.             {
  527.                printf ("   [DEVICE] dev  = 0x%08x (%d)\n", current_fsentry->u.device.dev, current_fsentry->u.device.dev);
  528.                printf ("   [DEVICE] rdev = 0x%08x (%d)\n", current_fsentry->u.device.rdev, current_fsentry->u.device.rdev);
  529.                printf ("   [DEVICE] path = \"%s\"\n", (char *) &current_fsentry->u.device.path); // convert from pointer to char array
  530.             }
  531.  
  532.             if ((current_fsentry->header.size == 0) || (current_offset + current_fsentry->header.size >= file.size))
  533.             {
  534.                LOG_WARNING ("this IFS file is corrupted (the size of this directory entry is invalid)");
  535.                goto endofdata;
  536.             }
  537.  
  538.             current_offset += current_fsentry->header.size;
  539.          }
  540.          if (imageheader_offset + image_header->hdr_dir_size < current_offset + sizeof (current_fsentry->header))
  541.             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);
  542.          current_offset += imageheader_offset + image_header->hdr_dir_size - current_offset; // padding was processed, jump over it
  543.  
  544.          // at this point we are past the directory entries; what is stored now, up to and until the image trailer, is the files' data
  545.          if (fsentry_count > 0)
  546.          {
  547.             while (current_offset < imagetrailer_offset) // and parse data up to the trailer
  548.             {
  549.                nearest_distance = SIZE_MAX;
  550.                nearest_index = SIZE_MAX;
  551.                for (fsentry_index = 0; fsentry_index < fsentry_count; fsentry_index++)
  552.                   if (S_ISREG (fsentries[fsentry_index]->header.mode) // if this directory entry a file (i.e. it has a data blob)...
  553.                       && (imageheader_offset + (size_t) fsentries[fsentry_index]->u.file.offset >= current_offset) // ... AND its data blob is still ahead of our current pointer ...
  554.                       && (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
  555.                   {
  556.                      nearest_distance = imageheader_offset + (size_t) fsentries[fsentry_index]->u.file.offset - current_offset; // then remember it
  557.                      nearest_index = fsentry_index;
  558.                   }
  559.                if (nearest_index == SIZE_MAX)
  560.                   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
  561.  
  562.                fsentry_index = nearest_index;
  563.                current_fsentry = fsentries[fsentry_index]; // quick access to closest fsentry
  564.  
  565.                // there may be padding before the file data
  566.                if (imageheader_offset + (size_t) current_fsentry->u.file.offset - current_offset > 0)
  567.                   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);
  568.                current_offset += imageheader_offset + (size_t) current_fsentry->u.file.offset - current_offset; // padding was processed, jump over it
  569.  
  570.                printf ("\n");
  571.                printf ("File data blob at offset 0x%zx (%zd):\n", current_offset, current_offset);
  572.                printf ("   corresponding dirent index: %zd/%zd\n", fsentry_index, fsentry_count);
  573.                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" : ""));
  574.                printf ("   corresponding path: \"%s\"\n", (char *) &current_fsentry->u.file.path); // convert from pointer to char array
  575.                printf ("   size 0x%zx (%zd) bytes\n", (size_t) current_fsentry->u.file.size, (size_t) current_fsentry->u.file.size);
  576.                if (current_offset + 4 < file.size)
  577.                   hex_printf (&file.bytes[current_offset], current_fsentry->u.file.size, "   data:\n");
  578.                if (current_offset + current_fsentry->u.file.size < file.size)
  579.                   printf ("   checksum %d\n", update_checksum (&file.bytes[current_offset], current_fsentry->u.file.size, is_foreign_endianness));
  580.                else
  581.                {
  582.                   LOG_WARNING ("this IFS file is corrupted (the size of this file data extends past the IFS size)");
  583.                   goto endofdata;
  584.                }
  585.  
  586.                current_offset += current_fsentry->u.file.size; // now jump over this file's data
  587.             }
  588.          }
  589.  
  590.          // ad this point we're past the last file data, there may be padding before the image trailer
  591.          if (imagetrailer_offset - current_offset > 0)
  592.             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);
  593.          current_offset += imagetrailer_offset - current_offset; // padding was processed, jump over it
  594.  
  595.          printf ("\n");
  596.          printf ("Image trailer at offset 0x%zx (%zd) - version %d:\n", current_offset, current_offset, (image_header->flags & IMAGE_FLAGS_TRAILER_V2 ? 2 : 1));
  597.          if (image_header->flags & IMAGE_FLAGS_TRAILER_V2)
  598.          {
  599.             for (byte_index = 0; byte_index < SHA512_DIGEST_LENGTH; byte_index++)
  600.                sprintf_s (&recorded_sha512[2 * byte_index], 3, "%02x", image_trailer_v2->sha512[byte_index]);
  601.             strcpy_s (computed_sha512, sizeof (computed_sha512), SHA512 (image_header, imagetrailer_offset - imageheader_offset, NULL));
  602.             recorded_checksum = image_trailer_v2->cksum;
  603.             computed_checksum = update_checksum (image_header, imagetrailer_offset + SHA512_DIGEST_LENGTH - imageheader_offset, is_foreign_endianness);
  604.             printf ("    sha512([0x%zx-0x%zx[) = %s - %s\n", imageheader_offset, imagetrailer_offset, recorded_sha512, (strcasecmp (computed_sha512, recorded_sha512) == 0 ? "GOOD" : "BAD"));
  605.             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"));
  606.             if (strcasecmp (computed_sha512, recorded_sha512) != 0)
  607.                printf ("Computed SHA-512: %s\n", computed_sha512);
  608.             if (computed_checksum != recorded_checksum)
  609.                printf ("Computed cksum: 0x%08x\n", computed_checksum);
  610.          }
  611.          else // old v1 trailer
  612.          {
  613.             recorded_checksum = image_trailer_v1->cksum;
  614.             computed_checksum = update_checksum (image_header, image_header->image_size - sizeof (image_trailer_v1_t), is_foreign_endianness);
  615.             printf ("    cksum([0x%zx-0x%zx[) = 0x%08x - %s\n", imageheader_offset, imagetrailer_offset, recorded_checksum, (computed_checksum == recorded_checksum ? "GOOD" : "BAD"));
  616.             if (computed_checksum != recorded_checksum)
  617.                printf ("Computed cksum: 0x%08x\n", computed_checksum);
  618.          }
  619.  
  620.          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)
  621.       }
  622.  
  623.       // 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
  624.       else
  625.       {
  626.          // if the first two bytes are Mark Zbikowski's initials, it's a PE executable, which means this is an EFI image
  627.          executable_format = ((file.size > 2) && (memcmp (file.bytes, "MZ", 2) == 0) ? "UEFI" : "BIOS"); // anything else is a BIOS image
  628.  
  629.          // 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)
  630.          for (byte_index = current_offset; byte_index < file.size - 6; byte_index++)
  631.             if (memcmp (&file.bytes[byte_index], "\xeb\x7e\xff\x00" "\x01\x00", 4 + 2) == 0)
  632.                break; // stop as soon as we find it
  633.  
  634.          if (byte_index >= file.size - 6)
  635.             break; // if not found, stop scanning
  636.  
  637.          bootfile_blobsize = byte_index - current_offset;
  638.          printf ("%s boot code at offset 0x%zx (%zd):\n", executable_format, current_offset, current_offset);
  639.          if ((strcmp (executable_format, "UEFI") == 0) && (byte_index >= sizeof (uefi64_header_t)))
  640.          {
  641.             uefi64_header_t *uefi_header = (uefi64_header_t *) file.bytes; // dump UEFI header details
  642.             printf ("   MZ header: signature: 5a 4d - 'MZ', good\n"); // we already validated this
  643.             printf ("   MZ header: number of bytes in last page: %d - %s\n", uefi_header->dos_header.bytes_in_last_page, (uefi_header->dos_header.bytes_in_last_page == 144 ? "good" : "unexpected value!?"));
  644.             printf ("   MZ header: number of 512-byte pages: %d - %s\n", uefi_header->dos_header.number_of_pages, (uefi_header->dos_header.number_of_pages == 3 ? "good" : "unexpected value!?"));
  645.             printf ("   MZ header: number of relocations: %d - %s\n", uefi_header->dos_header.number_of_relocations, (uefi_header->dos_header.number_of_relocations == 0 ? "good" : "unexpected value!?"));
  646.             printf ("   MZ header: header size in 16-byte paragraphs: %d - %s\n", uefi_header->dos_header.header_size_in_paragraphs, (uefi_header->dos_header.header_size_in_paragraphs == 4 ? "good" : "unexpected value!?"));
  647.             printf ("   MZ header: required/requested 16-byte paragraphs: %d/%d - %s\n", uefi_header->dos_header.required_paragraphs, uefi_header->dos_header.requested_paragraphs, (memcmp (&uefi_header->dos_header.required_paragraphs, "\0\0\xff\xff", 4) == 0 ? "good" : "unexpected value!?"));
  648.             printf ("   MZ header: initial relative relocatable segment offset fo SS: 0x%x - %s\n", uefi_header->dos_header.initial_relative_relocatable_segment_address_for_ss, (uefi_header->dos_header.initial_relative_relocatable_segment_address_for_ss == 0 ? "good" : "unexpected value!?"));
  649.             printf ("   MZ header: initial stack pointer value: 0x%04x - %s\n", uefi_header->dos_header.initial_stack_pointer_value, (uefi_header->dos_header.initial_stack_pointer_value == 184 ? "good" : "unexpected value!?"));
  650.             printf ("   MZ header: checksum (unused): 0x%x - %s\n", uefi_header->dos_header.unused_checksum, (uefi_header->dos_header.unused_checksum == 0 ? "good" : "unexpected value!?"));
  651.             printf ("   MZ header: initial instruction pointer value: 0x%04x - %s\n", uefi_header->dos_header.initial_instruction_pointer_value, (uefi_header->dos_header.initial_instruction_pointer_value == 0 ? "good" : "unexpected value!?"));
  652.             printf ("   MZ header: initial relative relocatable segment offset fo CS: 0x%x - %s\n", uefi_header->dos_header.initial_relative_relocatable_segment_address_for_cs, (uefi_header->dos_header.initial_relative_relocatable_segment_address_for_cs == 0 ? "good" : "unexpected value!?"));
  653.             printf ("   MZ header: absolute offset to relocation table: 0x%x - %s\n", uefi_header->dos_header.absolute_offset_to_relocation_table, (uefi_header->dos_header.absolute_offset_to_relocation_table == 64 ? "good" : "unexpected value!?"));
  654.             printf ("   MZ header: reserved_words1[4]: %s\n", (memcmp (uefi_header->dos_header.reserved_words1, "\0\0\0\0\0\0\0\0", 4 * sizeof (uint16_t)) == 0 ? "zerofilled, good" : "contains data, unexpected value!?"));
  655.             printf ("   MZ header: OEM identifier: 0x%04x - %s\n", uefi_header->dos_header.oem_identifier, (uefi_header->dos_header.oem_identifier == 0 ? "good" : "unexpected value!?"));
  656.             printf ("   MZ header: OEM info: 0x%04x - %s\n", uefi_header->dos_header.oem_info, (uefi_header->dos_header.oem_info == 0 ? "good" : "unexpected value!?"));
  657.             printf ("   MZ header: reserved_words2[10]: %s\n", (memcmp (uefi_header->dos_header.reserved_words2, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 10 * sizeof (uint16_t)) == 0 ? "zerofilled, good" : "contains data, unexpected value!?"));
  658.             printf ("   MZ header: absolute offset to PE header: 0x%08x (%d) - %s\n", uefi_header->dos_header.absolute_offset_to_pe_header, uefi_header->dos_header.absolute_offset_to_pe_header, (uefi_header->dos_header.absolute_offset_to_pe_header == 128 ? "good" : "unexpected value!?"));
  659.             hex_printf (uefi_header->dos_stub_bytes, 64, "   MZ header: DOS stub code bytes (64 bytes):\n");
  660.             printf ("   PE header: signature: %02x %02x %02x %02x - %s\n", uefi_header->pe_header.signature[0], uefi_header->pe_header.signature[1], uefi_header->pe_header.signature[2], uefi_header->pe_header.signature[3], (memcmp (uefi_header->pe_header.signature, "PE\0\0", 4) == 0 ? "'PE\\0\\0' - good" : "unexpected value!?"));
  661.             printf ("   PE header: machine type: 0x%04x - %s\n", uefi_header->pe_header.machine_type, (uefi_header->pe_header.machine_type == 0x8664 ? "AMD64, good" : "unexpected value!?"));
  662.             printf ("   PE header: number of sections: %d - %s\n", uefi_header->pe_header.number_of_sections, (uefi_header->pe_header.number_of_sections == 1 ? "good" : "unexpected value!?"));
  663.             printf ("   PE header: symbols table offset: 0x%x (%d) - %s\n", uefi_header->pe_header.offset_to_symbols_table, uefi_header->pe_header.offset_to_symbols_table, (uefi_header->pe_header.offset_to_symbols_table == 0 ? "good" : "unexpected value!?"));
  664.             printf ("   PE header: number of symbols: %d - %s\n", uefi_header->pe_header.number_of_symbols, (uefi_header->pe_header.number_of_symbols == 0 ? "good" : "unexpected value!?"));
  665.             printf ("   PE header: size of optional header: %d - %s\n", uefi_header->pe_header.size_of_optional_header, (uefi_header->pe_header.size_of_optional_header == 240 ? "good" : "unexpected value!?"));
  666.             printf ("   PE header: characteristics bitmap: 0x%04x - %s\n", uefi_header->pe_header.characteristics_bitmap, (uefi_header->pe_header.characteristics_bitmap == 0x223 ? "executable + uses large addresses + relocs stripped + debug info stripped, good" : "unexpected value!?"));
  667.             printf ("   optional header: signature: %02x %02x - %s\n", uefi_header->optional_header64.signature[0], uefi_header->optional_header64.signature[1], (memcmp (uefi_header->optional_header64.signature, "\x0b\x02", 2) == 0 ? "64-bit optional header magic, good" : "unexpected value!?"));
  668.             printf ("   optional header: linker version: %u.%u - %s\n", uefi_header->optional_header64.linker_version_major, uefi_header->optional_header64.linker_version_minor, (memcmp (&uefi_header->optional_header64.linker_version_major, "\0\0", 2) == 0 ? "good" : "unexpected value!?"));
  669.             printf ("   optional header: code size: 0x%x (%d) - %s\n", uefi_header->optional_header64.code_size, uefi_header->optional_header64.code_size, (byte_index + uefi_header->optional_header64.code_size == file.size ? "good" : "BAD (should equal file size minus UEFI boot prefix size)"));
  670.             printf ("   optional header: size of initialized data: 0x%x (%d) - %s\n", uefi_header->optional_header64.size_of_initialized_data, uefi_header->optional_header64.size_of_initialized_data, (uefi_header->optional_header64.size_of_initialized_data == 0 ? "good" : "unexpected value!?"));
  671.             printf ("   optional header: size of uninitialized data: 0x%x (%d) - %s\n", uefi_header->optional_header64.size_of_uninitialized_data, uefi_header->optional_header64.size_of_uninitialized_data, (uefi_header->optional_header64.size_of_uninitialized_data == 0 ? "good" : "unexpected value!?"));
  672.             printf ("   optional header: entrypoint address: 0x%x (%d)\n", uefi_header->optional_header64.entrypoint_address, uefi_header->optional_header64.entrypoint_address); // TODO: validate
  673.             printf ("   optional header: code base: 0x%x (%d) - %s\n", uefi_header->optional_header64.code_base, uefi_header->optional_header64.code_base, (uefi_header->optional_header64.code_base == 0 ? "good" : "unexpected value!?"));
  674.             printf ("   optional header: image base: 0x%zx (%zd)\n", uefi_header->optional_header64.image_base, uefi_header->optional_header64.image_base); // TODO: validate
  675.             printf ("   optional header: section alignment: 0x%x (%d) - %s\n", uefi_header->optional_header64.section_alignment, uefi_header->optional_header64.section_alignment, ((uefi_header->pe_header.machine_type == 0x8664) && (uefi_header->optional_header64.section_alignment == 4096) ? "good" : "unexpected value!? (should equal system page size)"));
  676.             printf ("   optional header: file alignment: 0x%x (%d) - %s\n", uefi_header->optional_header64.file_alignment, uefi_header->optional_header64.file_alignment, (uefi_header->optional_header64.file_alignment == 512 ? "good" : "unexpected value!? (must be a power of 2 between 512 and 65536)"));
  677.             printf ("   optional header: OS version: %u.%u - %s\n", uefi_header->optional_header64.os_version_major, uefi_header->optional_header64.os_version_minor, (memcmp (&uefi_header->optional_header64.os_version_major, "\0\0", 2) == 0 ? "good" : "unexpected value!?"));
  678.             printf ("   optional header: image version: %u.%u - %s\n", uefi_header->optional_header64.image_version_major, uefi_header->optional_header64.image_version_minor, (memcmp (&uefi_header->optional_header64.image_version_major, "\0\0", 2) == 0 ? "good" : "unexpected value!?"));
  679.             printf ("   optional header: subsystem version: %u.%u - %s\n", uefi_header->optional_header64.subsystem_version_major, uefi_header->optional_header64.subsystem_version_minor, (memcmp (&uefi_header->optional_header64.subsystem_version_major, "\0\0", 2) == 0 ? "good" : "unexpected value!?"));
  680.             printf ("   optional header: Win32 version value: 0x%x (%d) - %s\n", uefi_header->optional_header64.win32_version_value, uefi_header->optional_header64.win32_version_value, (uefi_header->optional_header64.win32_version_value == 0 ? "good" : "unexpected value!?"));
  681.             printf ("   optional header: image size: 0x%x (%d) - %s\n", uefi_header->optional_header64.image_size, uefi_header->optional_header64.image_size, (uefi_header->optional_header64.image_size == file.size ? "good" : "BAD (should equal file size)"));
  682.             printf ("   optional header: size of headers: 0x%x (%d) - %s\n", uefi_header->optional_header64.size_of_headers, uefi_header->optional_header64.size_of_headers, (uefi_header->optional_header64.size_of_headers == byte_index ? "good" : "BAD (should equal UEFI boot prefix size)"));
  683.             printf ("   optional header: checksum (unused): 0x%x - %s\n", uefi_header->optional_header64.unused_checksum, (uefi_header->optional_header64.unused_checksum == 0 ? "good" : "unexpected value!?"));
  684.             printf ("   optional header: subsystem type: 0x%x (%d) - %s\n", uefi_header->optional_header64.subsystem_type, uefi_header->optional_header64.subsystem_type, (uefi_header->optional_header64.subsystem_type == 10 ? "IMAGE_SUBSYSTEM_EFI_APPLICATION, good" : "BAD (should be IMAGE_SUBSYSTEM_EFI_APPLICATION i.e. 10 decimal)"));
  685.             printf ("   optional header: DLL characteristics bitmap: 0x%x (%d) - %s\n", uefi_header->optional_header64.dll_characteristics_bitmap, uefi_header->optional_header64.dll_characteristics_bitmap, (uefi_header->optional_header64.dll_characteristics_bitmap == 0 ? "nil, good" : "BAD (should be 0)"));
  686.             printf ("   optional header: stack commit/reserve size: %zd/%zd - %s\n", uefi_header->optional_header64.stack_commit_size, uefi_header->optional_header64.stack_reserve_size, ((uefi_header->optional_header64.stack_commit_size == uefi_header->optional_header64.section_alignment) && (uefi_header->optional_header64.stack_reserve_size == uefi_header->optional_header64.section_alignment) ? "good" : "unexpected value!? (both should equal system page size)"));
  687.             printf ("   optional header: heap commit/reserve size: %zd/%zd - %s\n", uefi_header->optional_header64.heap_commit_size, uefi_header->optional_header64.heap_reserve_size, ((uefi_header->optional_header64.heap_commit_size == 0) && (uefi_header->optional_header64.heap_reserve_size == 0) ? "good" : "unexpected value!? (both should be zero)"));
  688.             printf ("   optional header: loader flags: 0x%x (%d) - %s\n", uefi_header->optional_header64.unused_loader_flags, uefi_header->optional_header64.unused_loader_flags, (uefi_header->optional_header64.unused_loader_flags == 0 ? "good" : "BAD (should be zero)"));
  689.             printf ("   optional header: number of data directories: %d - %s\n", uefi_header->optional_header64.number_of_data_directories, (uefi_header->optional_header64.number_of_data_directories == 16 ? "good" : "unexpected value!?"));
  690.             printf ("   optional header: data directories: %s\n", (memcmp (uefi_header->optional_header64.data_directories, "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0", 8 * 16) == 0 ? "zerofilled, good" : "contains data, unexpected value!?"));
  691.             printf ("   image section header: section name: '%.8s' - %s\n", uefi_header->unique_section.section_name, (memcmp (uefi_header->unique_section.section_name, "image\0\0\0", 8) == 0 ? "good" : "unexpected value!?"));
  692.             printf ("   image section header: virtual size: 0x%x (%d) - %s\n", uefi_header->unique_section.virtual_size, uefi_header->unique_section.virtual_size, (uefi_header->unique_section.virtual_size == uefi_header->optional_header64.code_size ? "good" : "BAD (should equal code size)"));
  693.             printf ("   image section header: virtual address: 0x%x (%d) - %s\n", uefi_header->unique_section.virtual_address, uefi_header->unique_section.virtual_address, (uefi_header->unique_section.virtual_address == byte_index ? "good" : "BAD (should equal UEFI boot prefix size)"));
  694.             printf ("   image section header: raw data size: 0x%x (%d) - %s\n", uefi_header->unique_section.rawdata_size, uefi_header->unique_section.rawdata_size, (uefi_header->unique_section.rawdata_size == uefi_header->optional_header64.code_size ? "good" : "BAD (should equal code size)"));
  695.             printf ("   image section header: raw data offset: 0x%x (%d) - %s\n", uefi_header->unique_section.rawdata_offset, uefi_header->unique_section.rawdata_offset, (uefi_header->unique_section.rawdata_offset == byte_index ? "good" : "BAD (should equal UEFI boot prefix size)"));
  696.             printf ("   image section header: offset to relocations: 0x%x (%d) - %s\n", uefi_header->unique_section.offset_to_relocations, uefi_header->unique_section.offset_to_relocations, (uefi_header->unique_section.offset_to_relocations == 0 ? "good" : "unexpected value!?"));
  697.             printf ("   image section header: offset to line numbers: 0x%x (%d) - %s\n", uefi_header->unique_section.offset_to_linenos, uefi_header->unique_section.offset_to_linenos, (uefi_header->unique_section.offset_to_linenos == 0 ? "good" : "unexpected value!?"));
  698.             printf ("   image section header: number of relocations: 0x%x (%d) - %s\n", uefi_header->unique_section.relocation_count, uefi_header->unique_section.relocation_count, (uefi_header->unique_section.relocation_count == 0 ? "good" : "unexpected value!?"));
  699.             printf ("   image section header: number of line numbers: 0x%x (%d) - %s\n", uefi_header->unique_section.lineno_count, uefi_header->unique_section.lineno_count, (uefi_header->unique_section.lineno_count == 0 ? "good" : "unexpected value!?"));
  700.             printf ("   image section header: characteristics bitmap: 0x%04x - %s\n", uefi_header->unique_section.characteristics_bitmap, (uefi_header->unique_section.characteristics_bitmap == 0x60 ? "image contains code + image contains initialized data, good" : "unexpected value!?"));
  701.             hex_printf (uefi_header->trailing_padding, byte_index - 432, "   trailing padding (%zd bytes):\n", byte_index - 432);
  702.          }
  703.          else // BIOS boot prefixes are opaque so far (FIXME: decompile to ASM?)
  704.          {
  705.             printf ("   size 0x%zx (%zd) bytes\n", bootfile_blobsize, bootfile_blobsize);
  706.             printf ("   checksum 0x%08x\n", update_checksum (&file.bytes[current_offset], bootfile_blobsize, false)); // NOTE: endianness is not known yet -- assume same
  707.          }
  708.  
  709.          current_offset = byte_index; // now reach the next segment
  710.       }
  711.    }
  712.  
  713. endofdata:
  714.    // at this point there's nothing left we're able to parse
  715.    if (current_offset < file.size)
  716.    {
  717.       printf ("End of identifiable data reached.\n");
  718.       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);
  719.    }
  720.  
  721.    printf ("End of file reached at offset 0x%zx (%zd)\n", file.size, file.size);
  722.    printf ("IFS dissecation complete.\n");
  723.    return (0);
  724. }
  725.  
  726.  
  727. int dump_ifs_contents (const char *ifs_pathname, const char *outdir)
  728. {
  729.    static char outfile_pathname[MAXPATHLEN] = "";
  730.  
  731.    startup_header_t *startup_header = NULL;
  732.    size_t startupheader_offset = 0;
  733.    image_header_t *image_header = NULL;
  734.    size_t imageheader_offset = 0;
  735.    size_t imagetrailer_offset = 0;
  736.    fsentry_t **fsentries = NULL; // mallocated
  737.    size_t fsentry_count = 0;
  738.    fsentry_t *current_fsentry = NULL;
  739.    buffer_t decompression_dst;
  740.    size_t startupfile_blobsize = 0;
  741.    size_t compressed_blocksize;
  742.    struct utimbuf file_times = { 0, 0 };
  743.    char *exeformat_suffix = "";
  744.    void *reallocated_ptr;
  745.    uint8_t *decompressor_out;
  746.    uint8_t *decompressor_in;
  747.    size_t decompressor_outlen;
  748.    size_t bootfile_blobsize = 0;
  749.    size_t current_offset;
  750.    size_t fsentry_index;
  751.    size_t nearest_distance;
  752.    size_t nearest_index;
  753.    size_t byte_index;
  754.    buffer_t file;
  755.    FILE *fp;
  756.    int cf;
  757.  
  758.    // open and read IFS file
  759.    if (!Buffer_ReadFromFile (&file, ifs_pathname))
  760.       DIE_WITH_EXITCODE (1, "can't open \"%s\" for reading: %s\n", ifs_pathname, strerror (errno));
  761.  
  762.    // create the output directory
  763.    create_intermediate_dirs (outdir);
  764.    (void) mkdir (outdir, 0755);
  765.  
  766.    // parse file from start to end
  767.    current_offset = 0;
  768.    for (;;)
  769.    {
  770.       // does a startup header start here ?
  771.       if ((current_offset + sizeof (startup_header_t) < file.size)
  772.           && (startup_header == NULL)
  773.           && (memcmp (&file.bytes[current_offset], "\xeb\x7e\xff\x00", 4) == 0))
  774.       {
  775.          startupheader_offset = current_offset;
  776.          startup_header = (startup_header_t *) &file.bytes[startupheader_offset];
  777.  
  778.          // layout:
  779.          // [STARTUP HEADER]
  780.          // (startup file blob)
  781.          // [STARTUP TRAILER v1 or v2]
  782.  
  783.          // validate that the file can contain up to the startup trailer
  784.          if (current_offset + startup_header->startup_size > file.size)
  785.          {
  786.             LOG_WARNING ("this IFS file is corrupted (startup trailer extends past end of file)");
  787.             goto endofdata;
  788.          }
  789.  
  790.          // take note of the image compression flags
  791.          cf = startup_header->flags1 & STARTUP_HDR_FLAGS1_COMPRESS_MASK;
  792.  
  793.          // locate the right startup trailer at the right offset
  794.          if (startup_header->flags1 & STARTUP_HDR_FLAGS1_TRAILER_V2)
  795.             startupfile_blobsize = startup_header->startup_size - sizeof (startup_header_t) - sizeof (startup_trailer_v2_t);
  796.          else // old V1 trailer
  797.             startupfile_blobsize = startup_header->startup_size - sizeof (startup_header_t) - sizeof (startup_trailer_v1_t);
  798.  
  799.          current_offset += sizeof (startup_header_t); // jump over the startup header and reach the startup blob
  800.  
  801.          // write startup blob
  802.          sprintf_s (outfile_pathname, sizeof (outfile_pathname), "%s/startup%s.bin", outdir, exeformat_suffix);
  803.          fopen_s (&fp, outfile_pathname, "wb");
  804.          ASSERT (fp, "failed to open '%s': %s", outfile_pathname, strerror (errno));
  805.          fwrite (&file.bytes[current_offset], 1, startupfile_blobsize, fp);
  806.          fclose (fp);
  807.  
  808.          current_offset += startupfile_blobsize; // jump over the startup blob and reach the startup trailer
  809.          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
  810.       }
  811.  
  812.       // else does an image header start here ?
  813.       else if ((current_offset + sizeof (image_header_t) < file.size)
  814.                && (image_header == NULL)
  815.                && (((cf == STARTUP_HDR_FLAGS1_COMPRESS_NONE) && (memcmp (&file.bytes[current_offset], "imagefs", 7) == 0))
  816.                || (cf != STARTUP_HDR_FLAGS1_COMPRESS_NONE) && (startup_header->imagefs_size > 0)))
  817.       {
  818.          imageheader_offset = current_offset;
  819.          image_header = (image_header_t *) &file.bytes[imageheader_offset];
  820.  
  821.          // should we decompress it ?
  822.          if (cf != STARTUP_HDR_FLAGS1_COMPRESS_NONE)
  823.          {
  824.             // it appears mkifs compresses data in blocks, prefixed by 2-byte block size in BIG ENDIAN
  825.             Buffer_InitWithSize (&decompression_dst, startup_header->imagefs_size * 11 / 10); // mallocate and add 10% for safety
  826.             decompression_dst.size = 0;
  827.  
  828.             if (cf == STARTUP_HDR_FLAGS1_COMPRESS_UCL)
  829.                ASSERT (ucl_init () == UCL_E_OK, "UCL library initialization failed -- please recompile this tool with less aggressive optimizations");
  830.             else if (cf == STARTUP_HDR_FLAGS1_COMPRESS_LZO)
  831.                ASSERT (lzo_init () == LZO_E_OK, "LZO library initialization failed -- please recompile this tool with less aggressive optimizations");
  832.             else if (cf == STARTUP_HDR_FLAGS1_COMPRESS_ZLIB)
  833.             {
  834.                LOG_WARNING ("unimplemented compression scheme: zlib (FIXME)");
  835.                goto endofdata;
  836.             }
  837.             else
  838.             {
  839.                LOG_WARNING ("unsupported compression flags: 0x%2x", cf);
  840.                goto endofdata;
  841.             }
  842.  
  843.             // run the compressed payload (the imagefs) through the right decompression algorithm
  844.             for (;;)
  845.             {
  846.                compressed_blocksize = (file.bytes[current_offset + 0] << 8) | (file.bytes[current_offset + 1] << 0); // read block size word (in big engian)
  847.                current_offset += 2; // skip it
  848.                if (compressed_blocksize == 0)
  849.                   break; // a nil block size means end of stream is reached
  850.                //LOG_DEBUG ("about to decompress block of %zd bytes", compressed_blocksize);
  851.                decompressor_in = &file.bytes[current_offset];
  852.                decompressor_out = &decompression_dst.bytes[decompression_dst.size];
  853.                decompressor_outlen = 0;
  854.  
  855.                if (cf == STARTUP_HDR_FLAGS1_COMPRESS_UCL)
  856.                {
  857.                   // UCL compression. NOTE: the decompressor function used in startup-x86 is "ucl_nrv2b_decompress_8 / ucl_nrv2b_decompress_le16 / ucl_nrv2b_decompress_le32"
  858.                   static ucl_uint ucl_outlen; // have a different variable because of pointer size mismatch
  859.                   if (ucl_nrv2b_decompress_8 (decompressor_in, (ucl_uint) compressed_blocksize, decompressor_out, &ucl_outlen, NULL) != UCL_E_OK)
  860.                   {
  861.                      LOG_WARNING ("this IFS file is corrupted (UCL decompression failed)");
  862.                      goto endofdata;
  863.                   }
  864.                   decompressor_outlen = ucl_outlen;
  865.                }
  866.                else if (cf == STARTUP_HDR_FLAGS1_COMPRESS_LZO)
  867.                {
  868.                   // LZO decompression. NOTE: mkifs uses the full LZO package, whereas I use minilzo.
  869.                   static lzo_uint lzo_outlen; // have a different variable because of pointer size mismatch
  870.                   if (lzo1x_decompress (decompressor_in, (lzo_uint) compressed_blocksize, decompressor_out, &lzo_outlen, NULL) != LZO_E_OK)
  871.                   {
  872.                      LOG_WARNING ("this IFS file is corrupted (UCL decompression failed)");
  873.                      goto endofdata;
  874.                   }
  875.                   decompressor_outlen = lzo_outlen;
  876.                }
  877.                else if (cf == STARTUP_HDR_FLAGS1_COMPRESS_ZLIB)
  878.                   ; // TODO
  879.  
  880.                current_offset += compressed_blocksize;
  881.                decompression_dst.size += decompressor_outlen;
  882.             }
  883.  
  884.             LOG_INFO ("decompressed %zd bytes into %zd bytes\n", file.size - imageheader_offset, decompression_dst.size);
  885.  
  886.             // now place the decompressed buffer in the payload at the imagefs offset
  887.             ASSERT_WITH_ERRNO (Buffer_WriteBufferAt (&file, imageheader_offset, &decompression_dst));
  888.             current_offset = imageheader_offset; // jump back to where we put the uncompressed data
  889.             file.size = imageheader_offset + decompression_dst.size; // update IFS data size
  890.  
  891.             startup_header = (startup_header_t *) &file.bytes[startupheader_offset]; // fix the pointers that might have changed
  892.             image_header = (image_header_t *) &file.bytes[imageheader_offset]; // fix the pointers that might have changed
  893.          }
  894.  
  895.          // layout:
  896.          // [IMAGE HEADER]
  897.          // [image directory entries]
  898.          // [smallest file blobs up to KERNEL]
  899.          // [padding]
  900.          // [KERNEL]
  901.          // [rest of file blobs]
  902.          // [IMAGE FOOTER]
  903.  
  904.          // validate that the file can contain up to the image trailer
  905.          if (current_offset + image_header->image_size > file.size)
  906.          {
  907.             LOG_WARNING ("this IFS file is corrupted (image trailer extends past end of file)");
  908.             goto endofdata;
  909.          }
  910.  
  911.          // locate the image trailer at the right offset
  912.          if (image_header->flags & IMAGE_FLAGS_TRAILER_V2)
  913.             imagetrailer_offset = current_offset + image_header->image_size - sizeof (image_trailer_v2_t);
  914.          else // old V1 trailer
  915.             imagetrailer_offset = current_offset + image_header->image_size - sizeof (image_trailer_v1_t);
  916.  
  917.          current_offset += sizeof (image_header_t); // jump over the image header
  918.          current_offset += image_header->dir_offset - sizeof (image_header_t); // jump over possible padding
  919.  
  920.          // dump all directory entries until the last one included
  921.          fsentries = NULL;
  922.          fsentry_count = 0;
  923.          while (current_offset < imageheader_offset + image_header->hdr_dir_size)
  924.          {
  925.             current_fsentry = (fsentry_t *) &file.bytes[current_offset];
  926.  
  927.             if (imageheader_offset + image_header->hdr_dir_size - current_offset < sizeof (current_fsentry->header))
  928.                break; // end padding reached
  929.  
  930.             // stack up the filesystem entry pointers in an array while we read them
  931.             reallocated_ptr = realloc (fsentries, (fsentry_count + 1) * sizeof (fsentry_t *));
  932.             ASSERT_WITH_ERRNO (reallocated_ptr);
  933.             fsentries = reallocated_ptr;
  934.             fsentries[fsentry_count] = current_fsentry;
  935.             fsentry_count++;
  936.  
  937.             if ((current_fsentry->header.size == 0) || (current_offset + current_fsentry->header.size >= file.size))
  938.             {
  939.                LOG_WARNING ("this IFS file is corrupted (the size of this directory entry is invalid)");
  940.                goto endofdata;
  941.             }
  942.  
  943.             current_offset += current_fsentry->header.size;
  944.          }
  945.          current_offset += imageheader_offset + image_header->hdr_dir_size - current_offset; // jump over possible padding
  946.  
  947.          // at this point we are past the directory entries; what is stored now, up to and until the image trailer, is the files' data
  948.          if (fsentry_count > 0)
  949.          {
  950.             while (current_offset < imagetrailer_offset) // and parse data up to the trailer
  951.             {
  952.                nearest_distance = SIZE_MAX;
  953.                nearest_index = SIZE_MAX;
  954.                for (fsentry_index = 0; fsentry_index < fsentry_count; fsentry_index++)
  955.                   if (S_ISREG (fsentries[fsentry_index]->header.mode) // if this directory entry a file (i.e. it has a data blob)...
  956.                       && (imageheader_offset + (size_t) fsentries[fsentry_index]->u.file.offset >= current_offset) // ... AND its data blob is still ahead of our current pointer ...
  957.                       && (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
  958.                   {
  959.                      nearest_distance = imageheader_offset + (size_t) fsentries[fsentry_index]->u.file.offset - current_offset; // then remember it
  960.                      nearest_index = fsentry_index;
  961.                   }
  962.                if (nearest_index == SIZE_MAX)
  963.                   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
  964.  
  965.                fsentry_index = nearest_index;
  966.                current_fsentry = fsentries[fsentry_index]; // quick access to closest fsentry
  967.  
  968.                current_offset += imageheader_offset + (size_t) current_fsentry->u.file.offset - current_offset; // jump over possible padding
  969.  
  970.                if (current_offset + current_fsentry->u.file.size >= file.size)
  971.                {
  972.                   LOG_WARNING ("this IFS file is corrupted (the size of this file data extends past the IFS size)");
  973.                   goto endofdata;
  974.                }
  975.  
  976.                // write filesystem data entry
  977.                if (S_ISDIR (current_fsentry->header.mode))
  978.                {
  979.                   sprintf_s (outfile_pathname, sizeof (outfile_pathname), "%s/%s", outdir, (char *) &current_fsentry->u.dir.path); // convert from pointer to char array
  980.                   create_intermediate_dirs (outfile_pathname);
  981.                   (void) mkdir (outfile_pathname, current_fsentry->header.mode & 0777);
  982.                }
  983.                else if (S_ISLNK (current_fsentry->header.mode))
  984.                {
  985.                   sprintf_s (outfile_pathname, sizeof (outfile_pathname), "%s/%s", outdir, (char *) &current_fsentry->u.symlink.path); // convert from pointer to char array
  986.                   create_intermediate_dirs (outfile_pathname);
  987. #ifdef _WIN32
  988.                   fopen_s (&fp, outfile_pathname, "wb"); // on Windows create symlinks as plain files
  989.                   ASSERT (fp, "failed to open '%s': %s", outfile_pathname, strerror (errno));
  990.                   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
  991.                   fclose (fp);
  992. #else // !_WIN32, thus POSIX
  993.                   symlink (current_fsentry->u.symlink.contents, outfile_pathname); // on UNIX systems, just create the symlink for real
  994. #endif // _WIN32
  995.                }
  996.                else if (S_ISREG (current_fsentry->header.mode))
  997.                {
  998.                   sprintf_s (outfile_pathname, sizeof (outfile_pathname), "%s/%s", outdir, (char *) &current_fsentry->u.file.path); // convert from pointer to char array
  999.                   create_intermediate_dirs (outfile_pathname);
  1000.                   fopen_s (&fp, outfile_pathname, "wb"); // on Windows create symlinks as plain files
  1001.                   ASSERT (fp, "failed to open '%s': %s", outfile_pathname, strerror (errno));
  1002.                   fwrite (&file.bytes[current_offset], 1, current_fsentry->u.file.size, fp);
  1003.                   fclose (fp);
  1004.                }
  1005.                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
  1006.                {
  1007.                   sprintf_s (outfile_pathname, sizeof (outfile_pathname), "%s/%s", outdir, (char *) &current_fsentry->u.device.path); // convert from pointer to char array
  1008.                   create_intermediate_dirs (outfile_pathname);
  1009.                   fopen_s (&fp, outfile_pathname, "wb"); // on Windows create symlinks as plain files
  1010.                   ASSERT (fp, "failed to open '%s': %s", outfile_pathname, strerror (errno));
  1011.                   fprintf (fp, "%u:%u", current_fsentry->u.device.dev, current_fsentry->u.device.rdev);
  1012.                   fclose (fp);
  1013.                }
  1014.  
  1015.                // set created file mtime
  1016.                file_times.actime = current_fsentry->header.mtime;
  1017.                file_times.modtime = current_fsentry->header.mtime;
  1018.                utime (outfile_pathname, &file_times);
  1019.  
  1020.                // set created file mode
  1021. #ifndef _WIN32
  1022.                (void) chmod (outfile_pathname, current_fsentry->header.mode & 0777); // only on POSIX systems
  1023. #endif // !_WIN32
  1024.  
  1025.                current_offset += current_fsentry->u.file.size; // now jump over this file's data
  1026.             }
  1027.          }
  1028.  
  1029.          // ad this point we're past the last file data, there may be padding before the image trailer
  1030.          current_offset += imagetrailer_offset - current_offset; // jump over possible padding and reach the image trailer
  1031.          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)
  1032.       }
  1033.  
  1034.       // 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
  1035.       else
  1036.       {
  1037.          // if the first two bytes are Mark Zbikowski's initials, it's a PE executable, which means this is an EFI image
  1038.          exeformat_suffix = ((file.size > 2) && (memcmp (file.bytes, "MZ", 2) == 0) ? "-uefi" : "-bios"); // anything else is a BIOS image
  1039.  
  1040.          // 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)
  1041.          for (byte_index = current_offset; byte_index < file.size - 6; byte_index++)
  1042.             if (memcmp (&file.bytes[byte_index], "\xeb\x7e\xff\x00" "\x01\x00", 4 + 2) == 0)
  1043.                break; // stop as soon as we find it
  1044.  
  1045.          if (byte_index >= file.size - 6)
  1046.             break; // if not found, stop scanning
  1047.  
  1048.          bootfile_blobsize = byte_index - current_offset;
  1049.  
  1050.          // write boot blob
  1051.          sprintf_s (outfile_pathname, sizeof (outfile_pathname), "%s/boot%s.bin", outdir, exeformat_suffix);
  1052.          fopen_s (&fp, outfile_pathname, "wb");
  1053.          ASSERT (fp, "failed to open '%s': %s", outfile_pathname, strerror (errno));
  1054.          fwrite (&file.bytes[current_offset], 1, bootfile_blobsize, fp);
  1055.          fclose (fp);
  1056.  
  1057.          current_offset = byte_index; // now reach the next segment
  1058.       }
  1059.    }
  1060.  
  1061. endofdata:
  1062.    return (0);
  1063. }
  1064.  
  1065.  
  1066. int dump_file_hex (const char *pathname)
  1067. {
  1068.    buffer_t file;
  1069.  
  1070.    ASSERT_WITH_ERRNO (Buffer_ReadFromFile (&file, pathname));
  1071.    hex_fprintf (stdout, file.bytes, file.size, 16, "%s (%zd bytes):\n", pathname, file.size);
  1072.    return (0);
  1073. }
  1074.