Subversion Repositories QNX 8.QNX8 IFS tool

// ifstool.c -- portable reimplementation of QNX's mkifs by Pierre-Marie Baty <pm@pmbaty.com>

#include <stdint.h>

#include <stdbool.h>

#include <stdlib.h>

#include <stdio.h>

#include <string.h>

#include <errno.h>

#include <sys/stat.h>

#include <ctype.h>

#include <time.h>

#ifdef _MSC_VER

#include <io.h>

#define __ORDER_LITTLE_ENDIAN__ 1234

#define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__

#define __attribute__(x)

#define __builtin_bswap64(x) _byteswap_uint64 ((unsigned long long) (x))

#define S_IFIFO 0x1000

#define S_IFLNK 0xa000

#define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)

#define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)

#define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK)

#define strdup(s) _strdup ((s))

#define fseek(fp,off,m) _fseeki64 ((fp), (off), (m))

#define access(p,m) _access ((p), (m))

#define MAXPATHLEN 1024

#else // !_MSC_VER

#include <sys/param.h>

#include <unistd.h>

#endif // _MSC_VER

#ifdef _MSC_VER

#pragma pack(push)

#pragma pack(1)

#endif // _MSC_VER

#define ROUND_TO_UPPER_MULTIPLE(val,multiple) ((((val) + (size_t) (multiple) - 1) / (multiple)) * (multiple)) // note that val is being evaluated once, so it can be the result of a function call

#ifdef _WIN32

#define IS_DIRSEP(c) (((c) == '/') || ((c) == '\\'))

#define PATH_SEP ';'

#else // !_WIN32, thus POSIX

#define IS_DIRSEP(c) ((c) == '/')

#define PATH_SEP ':'

#endif // _WIN32

#define RECORD_SEP '\x1e' // ASCII record separator

#define RECORD_SEP_STR "\x1e" // ASCII record separator (as string)

#define WILL_BE_FILLED_LATER 0xbaadf00d

// bitmapped flags used in the flags1 member of the startup header

#define STARTUP_HDR_FLAGS1_VIRTUAL        (1 << 0)

#define STARTUP_HDR_FLAGS1_BIGENDIAN      (1 << 1)

//#define STARTUP_HDR_FLAGS1_COMPRESS_MASK  0x1c

//#define STARTUP_HDR_FLAGS1_COMPRESS_SHIFT 0x02

//#define STARTUP_HDR_FLAGS1_COMPRESS_NONE  0x00

//#define STARTUP_HDR_FLAGS1_COMPRESS_ZLIB  0x04

//#define STARTUP_HDR_FLAGS1_COMPRESS_LZO   0x08

//#define STARTUP_HDR_FLAGS1_COMPRESS_UCL   0x0c

#define STARTUP_HDR_FLAGS1_TRAILER_V2     (1 << 5) // if set, then a struct startup_trailer_v2 follows the startup. If the image is compressed, then the compressed imagefs is followed by a struct image_trailer_v2

#define STARTUP_HDR_MACHINE_X86_64  0x3e

#define STARTUP_HDR_MACHINE_AARCH64 0xb7

// bitmapped flags used in the flags member of the image header

#define IMAGE_FLAGS_BIGENDIAN  (1 << 0) // header, trailer, dirents in big-endian format

#define IMAGE_FLAGS_READONLY   (1 << 1) // do not try to write to image (rom/flash)

#define IMAGE_FLAGS_INO_BITS   (1 << 2) // inode bits valid

#define IMAGE_FLAGS_SORTED     (1 << 3) // dirent section is sorted (by pathname)

#define IMAGE_FLAGS_TRAILER_V2 (1 << 4) // image uses struct image_trailer_v2

// bitmapped flags superposed to a filesystem entry's inode number

#define IFS_INO_PROCESSED_ELF 0x80000000

#define IFS_INO_RUNONCE_ELF   0x40000000

#define IFS_INO_BOOTSTRAP_EXE 0x20000000

// SHA-512 block and digest sizes

#define SHA512_BLOCK_LENGTH 128 // in bytes

#define SHA512_DIGEST_LENGTH 64 // in bytes

// SHA-512 computation context structure type definition

typedef struct sha512_ctx_s

{

   uint64_t state[8];

   uint64_t bitcount[2];

   uint8_t buffer[SHA512_BLOCK_LENGTH];

} SHA512_CTX;

#if 0 // TODO: startup script compiler. Someday.

#define SCRIPT_FLAGS_EXTSCHED   0x01

#define SCRIPT_FLAGS_SESSION    0x02

#define SCRIPT_FLAGS_SCHED_SET  0x04

#define SCRIPT_FLAGS_CPU_SET    0x08

#define SCRIPT_FLAGS_BACKGROUND 0x20

#define SCRIPT_FLAGS_KDEBUG     0x40

#define SCRIPT_POLICY_NOCHANGE 0

#define SCRIPT_POLICY_FIFO     1

#define SCRIPT_POLICY_RR       2

#define SCRIPT_POLICY_OTHER    3

#define SCRIPT_TYPE_EXTERNAL        0

#define SCRIPT_TYPE_WAITFOR         1

#define SCRIPT_TYPE_REOPEN          2

#define SCRIPT_TYPE_DISPLAY_MSG     3

#define SCRIPT_TYPE_PROCMGR_SYMLINK 4

#define SCRIPT_TYPE_EXTSCHED_APS    5

#define SCRIPT_CHECKS_MS 100

#define SCRIPT_SCHED_EXT_NONE 0

#define SCRIPT_SCHED_EXT_APS  1

#define SCRIPT_APS_SYSTEM_PARTITION_ID   0

#define SCRIPT_APS_SYSTEM_PARTITION_NAME "System"

#define SCRIPT_APS_PARTITION_NAME_LENGTH 15

#define SCRIPT_APS_MAX_PARTITIONS        8

typedef struct __attribute__((packed)) bootscriptcmd_header_s

{

   uint16_t size; // size of cmd entry

   uint8_t type;

   uint8_t spare;

} bootscriptcmd_header_t;

typedef union bootscriptcmd_s

{

   struct __attribute__((packed)) script_external

   {

      bootscriptcmd_header_t hdr;

      uint8_t cpu; // CPU (turn into runmask)

      uint8_t flags;

      union script_external_extsched

      {

         uint8_t reserved[2];

         struct __attribute__((packed))

         {

            uint8_t id;

            uint8_t reserved[1];

         } aps;

      } extsched; // extended scheduler

      uint8_t policy; // POLICY_FIFO, POLICY_RR, ...

      uint8_t priority; // priority to run cmd at

      uint8_t argc; // # of args

      uint8_t envc; // # of environment entries

      char args[0]; // executable, argv, envp (null padded to 32-bit align)

   } external;

   struct __attribute__((packed)) script_waitfor_reopen

   {

      bootscriptcmd_header_t hdr;

      uint16_t checks;

      char fname[0]; // char fname[] (null padded to 32-bit align)

   } waitfor_reopen;

   struct __attribute__((packed)) script_display_msg

   {

      bootscriptcmd_header_t hdr;

      char msg[0]; // char msg[] (null padded to 32-bit align)

   } display_msg;

   struct __attribute__((packed)) script_procmgr_symlink

   {

      bootscriptcmd_header_t hdr;

      char src_dest[0]; // <src_name>, '\0', <dest_name> '\0' (null padded to 32-bit align)

   } procmgr_symlink;

   struct __attribute__((packed)) script_extsched_aps

   {

      bootscriptcmd_header_t hdr;

      uint8_t parent;

      uint8_t budget;

      uint16_t critical;

      uint8_t id;

      char pname[0]; // char pname[] (null padded to 32-bit align)

   } extsched_aps;

} bootscriptcmd_t;

#endif // 0

#define INITIAL_STARTUP_SCRIPT \

   /* procmgr_symlink /proc/boot/ldqnx-64.so.2 /usr/lib/ldqnx-64.so.2 */ \

   "\x34\x00" /*size*/ "\x04" /*type*/ "\x00" /*spare*/ "/proc/boot/ldqnx-64.so\0" "/usr/lib/ldqnx-64.so.2\0" \

   /* sh /proc/boot/startup.sh */ \

   "\x88\x00" /*size*/ "\x00" /*type*/ "\x00" /*spare*/ "\x00" /*CPU mask*/ "\x00" /*flags*/ "\x00\x00" /*reserved*/ "\x00" /*policy*/ "\x00" /*priority*/ "\02" /*argc*/ "\x02" /*envc*/ "sh\0" /*executable*/ "sh\0" "/proc/boot/startup.sh\0" /*argv*/ "PATH=/sbin:/usr/sbin:/bin:/usr/bin:/proc/boot\0" "LD_LIBRARY_PATH=/proc/boot:/lib:/lib/dll:/usr/lib\0" /*envp*/ \

   /* display_msg "Startup complete */ \

   "\x18\x00" /*size*/ "\x03" /*type*/ "\x00" /*spare*/ "Startup complete\n\0" "\x00\00" /*padding*/ \

   /* trailer */ \

   "\x00\x00\x00\x00"

#define INITIAL_STARTUP_SCRIPT_LEN (sizeof (INITIAL_STARTUP_SCRIPT) - 1)

typedef struct fsentry_s

{

   struct __attribute__((packed)) fsentry_header_s

   {

      uint16_t size; // size of dirent

      uint16_t extattr_offset; // if zero, no extattr data

      uint32_t ino; // if zero, skip entry

      uint32_t mode; // mode and perms of entry

      uint32_t gid;

      uint32_t uid;

      uint32_t mtime;

   } header;

   union fsentry_specific_u

   {

      struct fsentry_file_s // when (mode & S_IFMT) == S_IFREG

      {

         uint32_t offset; // offset from header

         uint32_t size;

         char *path; // null terminated path (no leading slash)

         char *UNSAVED_databuf; // file data blob buffer (NOT SAVED IN THE IFS)

      } file;

      struct fsentry_dir_s // when (mode & S_IFMT) == S_IFDIR

      {

         char *path; // null terminated path (no leading slash)

      } dir;

      struct fsentry_symlink_s // when (mode & S_IFMT) == S_IFLNK

      {

         uint16_t sym_offset; // offset to 'contents' from 'path'

         uint16_t sym_size; // strlen (contents)

         char *path; // null terminated path (no leading slash)

         char *contents; // null terminated symlink contents

      } symlink;

      struct fsentry_device_s // when (mode & S_IFMT) == S_IF<CHR|BLK|FIFO|NAM|SOCK>

      {

         uint32_t dev;

         uint32_t rdev;

         char *path; // null terminated path (no leading slash)

      } device;

   } u;

   bool UNSAVED_was_data_written; // whether this entry's data was written to the image (NOT SAVED IN THE IFS)

} fsentry_t;

typedef struct __attribute__((packed)) startup_header_s // size 256 bytes

{

                           // I - used by the QNX IPL

                           // S - used by the startup program

   uint8_t signature[4];   // [I ] Header signature, "\xeb\x7e\xff\x00"

   uint16_t version;       // [I ] Header version, i.e. 1

   uint8_t flags1;         // [IS] Misc flags, 0x21 (= 0x20 | STARTUP_HDR_FLAGS1_VIRTUAL)

   uint8_t flags2;         // [  ] No flags defined yet (0)

   uint16_t header_size;   // [ S] sizeof(struct startup_header), i.e. 256

   uint16_t machine;       // [IS] Machine type from elfdefinitions.h, i.e. 0x003E --> _ELF_DEFINE_EM(EM_X86_64, 62, "AMD x86-64 architecture")

   uint32_t startup_vaddr; // [I ] Virtual Address to transfer to after IPL is done, here 0x01403008 (appears in "Entry" column for "startup.*")

   uint32_t paddr_bias;    // [ S] Value to add to physical address to get a value to put into a pointer and indirected through, here 0 (no indirections)

   uint32_t image_paddr;   // [IS] Physical address of image, here 0x01400f30 (appears in "Offset" column for "startup-header" which is the first entry/start of file)

   uint32_t ram_paddr;     // [IS] Physical address of RAM to copy image to (startup_size bytes copied), here 0x01400f30 (same as above)

   uint32_t ram_size;      // [ S] Amount of RAM used by the startup program and executables contained in the file system, here 0x00cd6128 i.e. 13 459 752 dec. which is 13 Mb. i.e. IFS file size minus 0x9eee

   uint32_t startup_size;  // [I ] Size of startup (never compressed), here 0x02f148 or 192 840 bytes

   uint32_t stored_size;   // [I ] Size of entire image, here 0x00cd6128 (same as ram_size)

   uint32_t imagefs_paddr; // [IS] Set by IPL to where the imagefs is when startup runs (0)

   uint32_t imagefs_size;  // [ S] Size of uncompressed imagefs, here 0x00ca6fe0 or 13 266 912 bytes

   uint16_t preboot_size;  // [I ] Size of loaded before header, here 0xf30 or 3888 bytes (size of "bios.boot" file))

   uint16_t zero0;         // [  ] Zeros

   uint32_t zero[1];       // [  ] Zeros

   uint64_t addr_off;      // [ S] Offset to add to startup_vaddr, image_paddr, ram_paddr, and imagefs_paddr members, here zero (0)

   uint32_t info[48];      // [IS] Array of startup_info* structures (zero filled)

} startup_header_t;

typedef struct __attribute__((packed)) startup_trailer_s

{

   uint32_t cksum; // checksum from start of header to start of trailer

} startup_trailer_t;

// NOTE: The checksums in this trailer will only be valid prior to entering startup.

// Because the startup binary is executed in-place, its data segment will change once the program is running.

// Hence, any checksum validation would need to be done by the boot loader / IFS.

typedef struct __attribute__((packed)) startup_trailer_v2_s

{

   uint8_t sha512[64]; // SHA512 from start of header to start of trailer

   uint32_t cksum; // checksum from start of header to start of this member

} startup_trailer_v2_t;

typedef struct __attribute__((packed)) image_header_s

{

   uint8_t signature[7]; // image filesystem signature, i.e. "imagefs"

   uint8_t flags; // endian neutral flags, 0x1c

   uint32_t image_size; // size from header to end of trailer (here 0xca6fe0 or 13 266 912)

   uint32_t hdr_dir_size; // size from header to last dirent (here 0x12b8 or 4792)

   uint32_t dir_offset; // offset from header to first dirent (here 0x5c or 92)

   uint32_t boot_ino[4]; // inode of files for bootstrap pgms (here 0xa0000002, 0, 0, 0)

   uint32_t script_ino; // inode of file for script (here 3)

   uint32_t chain_paddr; // offset to next filesystem signature (0)

   uint32_t spare[10]; // zerofill

   uint32_t mountflags; // default _MOUNT_* from sys/iomsg.h (0)

   char mountpoint[4]; // default mountpoint for image ("/" + "\0\0\0")

} image_header_t;

typedef struct __attribute__((packed)) image_trailer_v1_s

{

   uint32_t cksum; // checksum from start of header to start of trailer

} image_trailer_v1_t;

// NOTE: the checksums in this trailer will only be valid until the first non-startup bootstrap binary (e.g., startup-verifier, procnto, ...) is invoked.

// Because bootstrap binaries execute in-place, their data segments will change once the programs are running.

// Hence, any checksum validation would need to be done either by the boot loader / IFS or by the startup.

typedef struct __attribute__((packed)) image_trailer_v2_s

{

   uint8_t sha512[64]; // SHA512 from start of image header to start of trailer

   uint32_t cksum; // checksum from start of header to start of this member

} image_trailer_v2_t;

#ifdef _MSC_VER

#pragma pack(pop)

#endif // _MSC_VER

typedef struct parms_s

{

   int dperms; // directory permissions (e.g. 0755)

   int perms; // file permissions (e.g. 0644)

   int uid; // owner user ID (e.g. 0 = root)

   int gid; // owner group ID (e.g. 0 = root)

   int st_mode; // entry type (e.g. S_IFREG for files) and permissions

   char prefix[MAXPATHLEN]; // install path (e.g. "proc/boot")

   bool should_compile_contents_as_startup_script;

   char search[10 * MAXPATHLEN]; // binary search path (the default one will be constructed at startup)

} parms_t;

// global variables

static char line_buffer[4096]; // scrap buffer for the IFS build file parser

static uint32_t image_base = 4 * 1024 * 1024; // default image base, as per QNX docs -- can be changed with the [image=XXXX] attribute in the IFS build file

static uint32_t image_end = UINT32_MAX; // default image end (no limit)

static uint32_t image_maxsize = UINT32_MAX; // default image max size (no limit)

static uint32_t image_totalsize = 0; // image total size, measured once all the blocks have been written to the output IFS file

static uint32_t image_align = 4; // default image alignment, as per QNX docs

static uint32_t image_kernel_ino = 0;

static uint32_t image_bootscript_ino = 0;

static char image_processor[16] = "x86_64"; // default CPU type for which this image is built, either "x86_64" or "aarch64le" (will be used to find out the right include paths under $QNX_TARGET)

static char *buildfile_pathname = NULL; // pathname of IFS build file

static int lineno = 0; // current line number in IFS build file

static char *QNX_TARGET = NULL; // value of the $QNX_TARGET environment variable

// prototypes of local functions

static void sha512_private_transform (SHA512_CTX *context, const uint64_t *data); // used internally in SHA512_Update() and SHA512_Final()

static void SHA512_Init (SHA512_CTX *context);

static void SHA512_Update (SHA512_CTX *context, void *data, size_t len);

static void SHA512_Final (uint8_t digest[SHA512_DIGEST_LENGTH], SHA512_CTX *context);

static uint8_t *SHA512 (void *data, size_t data_len, uint8_t *digest); // computes a SHA-512 in one pass (shortcut for SHA512_Init(), SHA512_Update() N times and SHA512_Final())

static int update_checksum_int32s (const int32_t start_value, const int32_t *data, const size_t len); // update the sum of an array of 32-bit signed integers

static long long read_integer (const char *str); // reads an integer number for a string that may be specified in either hex, octal or decimal base, and may have an optional unit suffix (k, m, g, t)

static int fwrite_filecontents (const char *pathname, FILE *fp); // dumps the contents of pathname into fp

static size_t fwrite_fsentry (const fsentry_t *fsentry, FILE *fp); // writes the given filesystem entry into fp (without its contents)

static size_t add_fsentry (fsentry_t **fsentries, size_t *fsentry_count, const char *stored_pathname, parms_t *entry_parms, const uint8_t *data, const size_t entry_datalen); // stack up a new filesystem entry

static int fsentry_compare_pathnames_cb (const void *a, const void *b); // qsort() comparison callback that sorts filesystem entries by pathnames

static int fsentry_compare_sizes_cb (const void *a, const void *b); // qsort() comparison callback that sorts filesystem entries by size

static void sha512_private_transform (SHA512_CTX *context, const uint64_t *data)

{

   // logical functions used in SHA-384 and SHA-512

   #define S64(b,x)      (((x) >> (b)) | ((x) << (64 - (b)))) // 64-bit rotate right

   #define Ch(x,y,z)     (((x) & (y)) ^ ((~(x)) & (z)))

   #define Maj(x,y,z)    (((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))

   #define Sigma0_512(x) (S64(28, (x)) ^ S64(34, (x)) ^ S64(39, (x)))

   #define Sigma1_512(x) (S64(14, (x)) ^ S64(18, (x)) ^ S64(41, (x)))

   #define sigma0_512(x) (S64( 1, (x)) ^ S64( 8, (x)) ^ ((x) >> 7))

   #define sigma1_512(x) (S64(19, (x)) ^ S64(61, (x)) ^ ((x) >> 6))

   // hash constant words K for SHA-384 and SHA-512

   static const uint64_t K512[80] = {

      0x428a2f98d728ae22ULL, 0x7137449123ef65cdULL, 0xb5c0fbcfec4d3b2fULL, 0xe9b5dba58189dbbcULL, 0x3956c25bf348b538ULL, 0x59f111f1b605d019ULL, 0x923f82a4af194f9bULL, 0xab1c5ed5da6d8118ULL,

      0xd807aa98a3030242ULL, 0x12835b0145706fbeULL, 0x243185be4ee4b28cULL, 0x550c7dc3d5ffb4e2ULL, 0x72be5d74f27b896fULL, 0x80deb1fe3b1696b1ULL, 0x9bdc06a725c71235ULL, 0xc19bf174cf692694ULL,

      0xe49b69c19ef14ad2ULL, 0xefbe4786384f25e3ULL, 0x0fc19dc68b8cd5b5ULL, 0x240ca1cc77ac9c65ULL, 0x2de92c6f592b0275ULL, 0x4a7484aa6ea6e483ULL, 0x5cb0a9dcbd41fbd4ULL, 0x76f988da831153b5ULL,

      0x983e5152ee66dfabULL, 0xa831c66d2db43210ULL, 0xb00327c898fb213fULL, 0xbf597fc7beef0ee4ULL, 0xc6e00bf33da88fc2ULL, 0xd5a79147930aa725ULL, 0x06ca6351e003826fULL, 0x142929670a0e6e70ULL,

      0x27b70a8546d22ffcULL, 0x2e1b21385c26c926ULL, 0x4d2c6dfc5ac42aedULL, 0x53380d139d95b3dfULL, 0x650a73548baf63deULL, 0x766a0abb3c77b2a8ULL, 0x81c2c92e47edaee6ULL, 0x92722c851482353bULL,

      0xa2bfe8a14cf10364ULL, 0xa81a664bbc423001ULL, 0xc24b8b70d0f89791ULL, 0xc76c51a30654be30ULL, 0xd192e819d6ef5218ULL, 0xd69906245565a910ULL, 0xf40e35855771202aULL, 0x106aa07032bbd1b8ULL,

      0x19a4c116b8d2d0c8ULL, 0x1e376c085141ab53ULL, 0x2748774cdf8eeb99ULL, 0x34b0bcb5e19b48a8ULL, 0x391c0cb3c5c95a63ULL, 0x4ed8aa4ae3418acbULL, 0x5b9cca4f7763e373ULL, 0x682e6ff3d6b2b8a3ULL,

      0x748f82ee5defb2fcULL, 0x78a5636f43172f60ULL, 0x84c87814a1f0ab72ULL, 0x8cc702081a6439ecULL, 0x90befffa23631e28ULL, 0xa4506cebde82bde9ULL, 0xbef9a3f7b2c67915ULL, 0xc67178f2e372532bULL,

      0xca273eceea26619cULL, 0xd186b8c721c0c207ULL, 0xeada7dd6cde0eb1eULL, 0xf57d4f7fee6ed178ULL, 0x06f067aa72176fbaULL, 0x0a637dc5a2c898a6ULL, 0x113f9804bef90daeULL, 0x1b710b35131c471bULL,

      0x28db77f523047d84ULL, 0x32caab7b40c72493ULL, 0x3c9ebe0a15c9bebcULL, 0x431d67c49c100d4cULL, 0x4cc5d4becb3e42b6ULL, 0x597f299cfc657e2aULL, 0x5fcb6fab3ad6faecULL, 0x6c44198c4a475817ULL

   };

   uint64_t     a, b, c, d, e, f, g, h, s0, s1;

   uint64_t     T1, T2, *W512 = (uint64_t *) context->buffer;

   int j;

   // initialize registers with the prev. intermediate value

   a = context->state[0]; b = context->state[1]; c = context->state[2]; d = context->state[3]; e = context->state[4]; f = context->state[5]; g = context->state[6]; h = context->state[7];

   for (j = 0; j < 16; j++)

   {

#if __BYTE_ORDER__ ==  __ORDER_LITTLE_ENDIAN__

      W512[j] = __builtin_bswap64 (*data); // convert to host byte order

#elif // __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__

      W512[j] = *data;

#else // __BYTE_ORDER__ == ???

#error Please port this SHA-512 code to your exotic endianness platform. What are you compiling this on? PDP? Honeywell?

#endif // __BYTE_ORDER__ ==  __ORDER_LITTLE_ENDIAN__

      // apply the SHA-512 compression function to update a..h

      T1 = h + Sigma1_512 (e) + Ch (e, f, g) + K512[j] + W512[j];

      T2 = Sigma0_512 (a) + Maj (a, b, c);

      // update registers

      h = g; g = f; f = e; e = d + T1; d = c; c = b; b = a; a = T1 + T2;

      data++;

   }

   for (; j < 80; j++)

   {

      // part of the message block expansion

      s0 = W512[(j + 1) & 0x0f];

      s0 = sigma0_512 (s0);

      s1 = W512[(j + 14) & 0x0f];

      s1 = sigma1_512 (s1);

      // apply the SHA-512 compression function to update a..h

      T1 = h + Sigma1_512 (e) + Ch (e, f, g) + K512[j] + (W512[j & 0x0f] += s1 + W512[(j + 9) & 0x0f] + s0);

      T2 = Sigma0_512 (a) + Maj (a, b, c);

      // update registers

      h = g; g = f; f = e; e = d + T1; d = c; c = b; b = a; a = T1 + T2;

   }

   // compute the current intermediate hash value

   context->state[0] += a; context->state[1] += b; context->state[2] += c; context->state[3] += d; context->state[4] += e; context->state[5] += f; context->state[6] += g; context->state[7] += h;

   // clean up

   a = b = c = d = e = f = g = h = T1 = T2 = 0;

   #undef sigma1_512

   #undef sigma0_512

   #undef Sigma1_512

   #undef Sigma0_512

   #undef Maj

   #undef Ch

   #undef S64

   return;

}

static void SHA512_Init (SHA512_CTX *context)

{

   // initial hash value H for SHA-512

   static const uint64_t sha512_initial_hash_value[8] = {

      0x6a09e667f3bcc908ULL, 0xbb67ae8584caa73bULL, 0x3c6ef372fe94f82bULL, 0xa54ff53a5f1d36f1ULL, 0x510e527fade682d1ULL, 0x9b05688c2b3e6c1fULL, 0x1f83d9abfb41bd6bULL, 0x5be0cd19137e2179ULL

   };

   memcpy (context->state, sha512_initial_hash_value, SHA512_DIGEST_LENGTH);

   memset (context->buffer, 0, SHA512_BLOCK_LENGTH);

   context->bitcount[0] = context->bitcount[1] = 0;

}

void SHA512_Update (SHA512_CTX *context, void *datain, size_t len)

{

   #define ADDINC128(w,n) do { \

           (w)[0] += (uint64_t) (n); \

           if ((w)[0] < (n)) \

                   (w)[1]++; \

   } while (0) // macro for incrementally adding the unsigned 64-bit integer n to the unsigned 128-bit integer (represented using a two-element array of 64-bit words

   size_t freespace, usedspace;

   const uint8_t *data = (const uint8_t *) datain;

   if (len == 0)

      return; // calling with empty data is valid - we do nothing

   usedspace = (context->bitcount[0] >> 3) % SHA512_BLOCK_LENGTH;

   if (usedspace > 0)

   {

      // calculate how much free space is available in the buffer

      freespace = SHA512_BLOCK_LENGTH - usedspace;

      if (len >= freespace)

      {

         // fill the buffer completely and process it

         memcpy (&context->buffer[usedspace], data, freespace);

         ADDINC128 (context->bitcount, freespace << 3);

         len -= freespace;

         data += freespace;

         sha512_private_transform (context, (uint64_t *) context->buffer);

      }

      else

      {

         // the buffer is not full yet

         memcpy (&context->buffer[usedspace], data, len);

         ADDINC128 (context->bitcount, len << 3);

         // clean up

         usedspace = freespace = 0;

         return;

      }

   }

   while (len >= SHA512_BLOCK_LENGTH)

   {

      // process as many complete blocks as we can

      sha512_private_transform (context, (uint64_t *) data);

      ADDINC128 (context->bitcount, SHA512_BLOCK_LENGTH << 3);

      len -= SHA512_BLOCK_LENGTH;

      data += SHA512_BLOCK_LENGTH;

   }

   if (len > 0)

   {

      // save leftovers

      memcpy (context->buffer, data, len);

      ADDINC128 (context->bitcount, len << 3);

   }

   // clean up

   usedspace = freespace = 0;

   #undef ADDINC128

   return;

}

static void SHA512_Final (uint8_t digest[SHA512_DIGEST_LENGTH], SHA512_CTX *context)

{

   #define SHA512_SHORT_BLOCK_LENGTH (SHA512_BLOCK_LENGTH - 16)

   size_t usedspace;

   union { uint8_t *as_bytes; uint64_t *as_uint64s; } cast_var = { NULL };

   // if no digest buffer is passed, don't bother finalizing the computation

   if (digest != NULL)

   {

      usedspace = (context->bitcount[0] >> 3) % SHA512_BLOCK_LENGTH;

#if __BYTE_ORDER__ ==  __ORDER_LITTLE_ENDIAN__

      context->bitcount[0] = __builtin_bswap64 (context->bitcount[0]); // convert from host byte order

      context->bitcount[1] = __builtin_bswap64 (context->bitcount[1]); // convert from host byte order

#endif // __BYTE_ORDER__ ==  __ORDER_LITTLE_ENDIAN__

      if (usedspace > 0)

      {

         // begin padding with a 1 bit

         context->buffer[usedspace++] = 0x80;

         if (usedspace <= SHA512_SHORT_BLOCK_LENGTH)

            memset (&context->buffer[usedspace], 0, SHA512_SHORT_BLOCK_LENGTH - usedspace); // set-up for the last transform

         else

         {

            if (usedspace < SHA512_BLOCK_LENGTH)

               memset (&context->buffer[usedspace], 0, SHA512_BLOCK_LENGTH - usedspace);

            sha512_private_transform (context, (uint64_t *) context->buffer); // do second-to-last transform

            memset (context->buffer, 0, SHA512_BLOCK_LENGTH - 2); // and set-up for the last transform

         }

      }

      else // usedspace == 0

      {

         memset (context->buffer, 0, SHA512_SHORT_BLOCK_LENGTH); // prepare for final transform

         *context->buffer = 0x80; // begin padding with a 1 bit

      }

      // store the length of input data (in bits)

      cast_var.as_bytes = context->buffer;

      cast_var.as_uint64s[SHA512_SHORT_BLOCK_LENGTH / 8 + 0] = context->bitcount[1];

      cast_var.as_uint64s[SHA512_SHORT_BLOCK_LENGTH / 8 + 1] = context->bitcount[0];

      // final transform

      sha512_private_transform (context, (uint64_t *) context->buffer);

      // save the hash data for output

#if __BYTE_ORDER__ ==  __ORDER_LITTLE_ENDIAN__

      for (int j = 0; j < 8; j++)

         context->state[j] = __builtin_bswap64 (context->state[j]); // convert to host byte order

#endif // __BYTE_ORDER__ ==  __ORDER_LITTLE_ENDIAN__

      memcpy (digest, context->state, SHA512_DIGEST_LENGTH);

   }

   // zero out state data

   memset (context, 0, sizeof (SHA512_CTX));

   #undef SHA512_SHORT_BLOCK_LENGTH

   return;

}

static uint8_t *SHA512 (void *data, size_t data_len, uint8_t *digest)

{

   // computes the SHA-512 hash of a block of data in one pass and write it to digest

   SHA512_CTX ctx;

   SHA512_Init (&ctx);

   SHA512_Update (&ctx, data, data_len);

   SHA512_Final (digest, &ctx);

   return (digest);

}

static int update_checksum_int32s (const int32_t start_value, const int32_t *data, const size_t len)

{

   // compute the sum of an array of 32-bit signed integers

   size_t byte_index;

   int32_t sum = start_value;

   for (byte_index = 0; byte_index < len; byte_index += sizeof (int32_t))

      sum += *data++;

   return (sum);

}

static long long read_integer (const char *str)

{

   // reads a number for a string that may be specified in either hex, octal or decimal base, and may have an optional unit suffix (k, m, g, t)

   char *endptr = NULL;

   long long ret = strtoll (str, &endptr, 0); // use strtoll() to handle hexadecimal (0x...), octal (0...) and decimal (...) bases

   if (endptr != NULL)

   {

      if ((*endptr == 'k') || (*endptr == 'K')) ret *= (size_t) 1024;

      else if ((*endptr == 'm') || (*endptr == 'M')) ret *= (size_t) 1024 * 1024;

      else if ((*endptr == 'g') || (*endptr == 'G')) ret *= (size_t) 1024 * 1024 * 1024;

      else if ((*endptr == 't') || (*endptr == 'T')) ret *= (size_t) 1024 * 1024 * 1024 * 1024; // future-proof enough, I suppose?

   }

   return (ret);

}

static int fwrite_filecontents (const char *pathname, FILE *fp)

{

   // dumps the binary contents of pathname to fp

   uint8_t *blob_buffer;

   size_t blob_size;

   FILE *blob_fp;

   int ret;

   blob_fp = fopen (pathname, "rb");

   if (blob_fp == NULL)

      return (-1); // errno is set

   fseek (blob_fp, 0, SEEK_END);

   blob_size = ftell (blob_fp);

   blob_buffer = malloc (blob_size);

   if (blob_buffer == NULL)

   {

      fclose (blob_fp);

      return (-1); // errno is set to ENOMEM

   }

   fseek (blob_fp, 0, SEEK_SET);

   fread (blob_buffer, 1, blob_size, blob_fp);

   fclose (blob_fp);

   ret = (int) fwrite (blob_buffer, 1, blob_size, fp);

   free (blob_buffer);

   return (ret);

}

static size_t fwrite_fsentry (const fsentry_t *fsentry, FILE *fp)

{

   static const uint8_t zeropad_buffer[] = "\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";

   size_t datalen;

   size_t count;

   count = 0;

   if (fp != NULL)

      fwrite (&fsentry->header, sizeof (fsentry->header), 1, fp); // write the entry header (PACKED STRUCT)

   count += sizeof (fsentry->header);

   if (S_ISREG (fsentry->header.mode))

   {

      if (fp != NULL)

      {

         fwrite (&fsentry->u.file.offset, sizeof (uint32_t), 1, fp); // write offset

         fwrite (&fsentry->u.file.size,   sizeof (uint32_t), 1, fp); // write size

      }

      count += 2 * sizeof (uint32_t);

      datalen = strlen (fsentry->u.file.path) + 1;

      if (fp != NULL)

         fwrite (fsentry->u.file.path, (size_t) datalen, 1, fp); // write null-terminated path (no leading slash)

      count += datalen;

   }

   else if (S_ISDIR (fsentry->header.mode))

   {

      datalen = strlen (fsentry->u.dir.path) + 1;

      if (fp != NULL)

         fwrite (fsentry->u.dir.path, (size_t) datalen, 1, fp); // write null-terminated path (no leading slash)

      count += datalen;

   }

   else if (S_ISLNK (fsentry->header.mode))

   {

      if (fp != NULL)

      {

         fwrite (&fsentry->u.symlink.sym_offset, sizeof (uint16_t), 1, fp); // write offset

         fwrite (&fsentry->u.symlink.sym_size,   sizeof (uint16_t), 1, fp); // write size

      }

      count += 2 * sizeof (uint16_t);

      datalen = strlen (fsentry->u.symlink.path) + 1;

      if (fp != NULL)

         fwrite (fsentry->u.symlink.path, (size_t) datalen, 1, fp); // write null-terminated path (no leading slash)

      count += datalen;

      datalen = strlen (fsentry->u.symlink.contents) + 1;

      if (fp != NULL)

         fwrite (fsentry->u.symlink.contents, (size_t) datalen, 1, fp); // write null-terminated symlink contents

      count += datalen;

   }

   else

   {

      if (fp != NULL)

      {

         fwrite (&fsentry->u.device.dev,  sizeof (uint32_t), 1, fp); // write dev number

         fwrite (&fsentry->u.device.rdev, sizeof (uint32_t), 1, fp); // write rdev number

      }

      count += 2 * sizeof (uint32_t);

      datalen = strlen (fsentry->u.device.path) + 1;

      if (fp != NULL)

         fwrite (fsentry->u.device.path, (size_t) datalen, 1, fp); // write null-terminated path (no leading slash)

      count += datalen;

   }

   if ((fp != NULL) && (count % image_align != 0))

      fwrite (zeropad_buffer, count % image_align, 1, fp); // pad as necessary

   count = ROUND_TO_UPPER_MULTIPLE (count, image_align);

   return (count);

}

static size_t add_fsentry (fsentry_t **fsentries, size_t *fsentry_count, const char *stored_pathname, parms_t *entry_parms, const uint8_t *entry_data, const size_t entry_datalen)

{

   static char candidate_pathname[1024];

   static char *MKIFS_PATH = NULL;

   static int inode_count = 0; // will be preincremented each time this function is called

   void *reallocated_ptr;

   char processor_base[16];

   struct stat stat_buf;

   uint8_t *data_buffer = NULL;

   size_t data_len = 0;

   uint32_t mtime = 0;

   uint32_t extra_ino_flags = 0;

   fsentry_t *fsentry;

   char *token;

   FILE *fp;

   if (S_ISDIR (entry_parms->st_mode)) // are we storing a directory ?

   {

      fprintf (stderr, "directory: ino 0x%x uid %d gid %d mode 0%o path \"%s\"\n", inode_count + 1, entry_parms->uid, entry_parms->gid, entry_parms->st_mode, stored_pathname);

   }

   else if (S_ISREG (entry_parms->st_mode)) // else are we storing a regular file ?