sics/fortify.c

/*
 * FILE:
 *   fortify.c
 *
 * DESCRIPTION:
 *     A fortified shell for malloc, realloc, calloc and free.
 *     To use Fortify, each source file will need to #include "fortify.h".  To
 * enable  Fortify,  define the symbol FORTIFY.  If FORTIFY is not defined, it
 * will compile away to nothing.  If you do not have stdout available, you may
 * wish  to  set  an  alternate output function.  See Fortify_SetOutputFunc(),
 * below.
 *     You will also need to link in fortify.o
 *
 *     None of the functions in this file should really be called
 *   directly; they really should be called through the macros
 *   defined in fortify.h
 *
 */
#ifdef FORTIFY

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <ctype.h>

#define __FORTIFY_C__           /* So fortify.h knows to not define the fortify macros */
#include "fortify.h"

#include "ufortify.h"           /* the user's options */

struct Header {
  char *File;                   /* The sourcefile of the caller   */
  unsigned long Line;           /* The sourceline of the caller   */
  size_t Size;                  /* The size of the malloc'd block */
  struct Header *Prev,          /* List pointers                  */
  *Next;
  int Scope;
  int Checksum;                 /* For validating the Header structure; see ChecksumHeader() */
};

static int CheckBlock(struct Header *h, char *file, unsigned long line);
static int CheckFortification(unsigned char *ptr, unsigned char value,
                              size_t size);
static void SetFortification(unsigned char *ptr, unsigned char value,
                             size_t size);
static void OutputFortification(unsigned char *ptr, unsigned char value,
                                size_t size);
static int IsHeaderValid(struct Header *h);
static void MakeHeaderValid(struct Header *h);
static int ChecksumHeader(struct Header *h);
static int IsOnList(struct Header *h);
static void OutputHeader(struct Header *h);
static void OutputMemory(struct Header *h);

static void st_DefaultOutput(char *String)
{
  printf(String);
}

static struct Header *st_Head = 0;      /* Head of alloc'd memory list */
static OutputFuncPtr st_Output = st_DefaultOutput;      /* Output function for errors */
static char st_Buffer[256];     /* Temporary buffer for sprintf's */
static int st_Disabled = 0;     /* If true, Fortify is inactive */
static int st_MallocFailRate = 0;       /* % of the time to fail mallocs */

static char *st_LastVerifiedFile = "unknown";
static unsigned long st_LastVerifiedLine = 0;
static int st_Scope = 0;
static void OutputLastVerifiedPoint(void);

/*
 * Fortify_malloc() - Allocates a block of memory, with extra bits for
 *                    misuse protection/detection. 
 *
 *    Features:
 *     +  Adds the malloc'd memory onto Fortify's own private list.
 *        (With a checksum'd header to detect corruption of the memory list)
 *     +  Places sentinals on either side of the user's memory with
 *        known data in them, to detect use outside of the bounds
 *        of the block
 *     +  Initializes the malloc'd memory to some "nasty" value, so code
 *        can't rely on it's contents.
 *     +  Can check all sentinals on every malloc.
 *     +  Can generate a warning message on a malloc fail.
 *     +  Can randomly "fail" at a set fail rate
 */
void *FORTIFY_STORAGE
Fortify_malloc(size_t size, char *file, unsigned long line)
{
  unsigned char *ptr;
  struct Header *h;

  FORTIFY_LOCK();

  if (st_Disabled) {
    ptr = malloc(size);
    FORTIFY_UNLOCK();
    return (ptr);
  }
#ifdef CHECK_ALL_MEMORY_ON_MALLOC
  Fortify_CheckAllMemory(file, line);
#endif

  if (size == 0) {
#ifdef WARN_ON_ZERO_MALLOC
    sprintf(st_Buffer,
            "\nFortify: %s.%ld\n         malloc(0) attempted failed\n",
            file, line);
    st_Output(st_Buffer);
#endif

    FORTIFY_UNLOCK();
    return (0);
  }

  if (st_MallocFailRate > 0) {
    if (rand() % 100 < st_MallocFailRate) {
#ifdef WARN_ON_FALSE_FAIL
      sprintf(st_Buffer,
              "\nFortify: %s.%ld\n         malloc(%ld) \"false\" failed\n",
              file, line, (unsigned long) size);
      st_Output(st_Buffer);
#endif
      FORTIFY_UNLOCK();
      return (0);
    }
  }

  /*
   * malloc the memory, including the space for the header and fortification
   * buffers
   */
#ifdef WARN_ON_SIZE_T_OVERFLOW
  {
    size_t private_size = sizeof(struct Header)
        + FORTIFY_BEFORE_SIZE + size + FORTIFY_AFTER_SIZE;

    if (private_size < size) {  /* Check to see if the added baggage is larger than size_t */
      sprintf(st_Buffer,
              "\nFortify: %s.%ld\n         malloc(%ld) has overflowed size_t.\n",
              file, line, (unsigned long) size);
      st_Output(st_Buffer);
      FORTIFY_UNLOCK();
      return (0);
    }
  }
#endif

  ptr = malloc(sizeof(struct Header) +
               FORTIFY_BEFORE_SIZE + size + FORTIFY_AFTER_SIZE);
  if (!ptr) {
#ifdef WARN_ON_MALLOC_FAIL
    sprintf(st_Buffer, "\nFortify: %s.%ld\n         malloc(%ld) failed\n",
            file, line, (unsigned long) size);
    st_Output(st_Buffer);
#endif

    FORTIFY_UNLOCK();
    return (0);
  }

  /*
   * Initialize and validate the header
   */
  h = (struct Header *) ptr;

  h->Size = size;

  h->File = file;
  h->Line = line;

  h->Next = st_Head;
  h->Prev = 0;

  h->Scope = st_Scope;

  if (st_Head) {
    st_Head->Prev = h;
    MakeHeaderValid(st_Head);
  }

  st_Head = h;

  MakeHeaderValid(h);


  /*
   * Initialize the fortifications
   */
  SetFortification(ptr + sizeof(struct Header),
                   FORTIFY_BEFORE_VALUE, FORTIFY_BEFORE_SIZE);
  SetFortification(ptr + sizeof(struct Header) + FORTIFY_BEFORE_SIZE +
                   size, FORTIFY_AFTER_VALUE, FORTIFY_AFTER_SIZE);

#ifdef FILL_ON_MALLOC
  /*
   * Fill the actual user memory
   */
  SetFortification(ptr + sizeof(struct Header) + FORTIFY_BEFORE_SIZE,
                   FILL_ON_MALLOC_VALUE, size);
#endif

  /*
   * We return the address of the user's memory, not the start of the block,
   * which points to our magic cookies
   */

  FORTIFY_UNLOCK();

  return (ptr + sizeof(struct Header) + FORTIFY_BEFORE_SIZE);
}

/* 
 * Fortify_free() - This free must be used for all memory allocated with
 *                  Fortify_malloc().
 *
 *   Features:
 *     + Pointers are validated before attempting a free - the pointer
 *       must point to a valid malloc'd bit of memory.
 *     + Detects attempts at freeing the same block of memory twice
 *     + Can clear out memory as it is free'd, to prevent code from using
 *       the memory after it's been freed.
 *     + Checks the sentinals of the memory being freed.
 *     + Can check the sentinals of all memory.
 */

void FORTIFY_STORAGE
Fortify_free(void *uptr, char *file, unsigned long line)
{
  unsigned char *ptr =
      (unsigned char *) uptr - sizeof(struct Header) - FORTIFY_BEFORE_SIZE;
  struct Header *h = (struct Header *) ptr;

  FORTIFY_LOCK();

  if (st_Disabled) {
    free(uptr);
    FORTIFY_UNLOCK();
    return;
  }
#ifdef CHECK_ALL_MEMORY_ON_FREE
  Fortify_CheckAllMemory(file, line);
#endif

#ifdef PARANOID_FREE
  if (!IsOnList(h)) {
    sprintf(st_Buffer,
            "\nFortify: %s.%ld\n         Invalid pointer, corrupted header, or possible free twice\n",
            file, line);
    st_Output(st_Buffer);
    OutputLastVerifiedPoint();
    goto fail;
  }
#endif

  if (!CheckBlock(h, file, line))
    goto fail;

  /*
   * Remove the block from the list
   */
  if (h->Prev) {
    if (!CheckBlock(h->Prev, file, line))
      goto fail;

    h->Prev->Next = h->Next;
    MakeHeaderValid(h->Prev);
  } else
    st_Head = h->Next;

  if (h->Next) {
    if (!CheckBlock(h->Next, file, line))
      goto fail;

    h->Next->Prev = h->Prev;
    MakeHeaderValid(h->Next);
  }
#ifdef FILL_ON_FREE
  /*
   * Nuke out all memory that is about to be freed
   */
  SetFortification(ptr, FILL_ON_FREE_VALUE,
                   sizeof(struct Header) + FORTIFY_BEFORE_SIZE + h->Size +
                   FORTIFY_AFTER_SIZE);
#endif

  /*
   * And do the actual free
   */
  free(ptr);
  FORTIFY_UNLOCK();
  return;

fail:
  sprintf(st_Buffer, "         free(%p) failed\n", uptr);
  st_Output(st_Buffer);
  FORTIFY_UNLOCK();
}

/*
 * Fortify_realloc() - Uses Fortify_malloc() and Fortify_free() to implement
 *                     realloc().
 *
 *   Features: 
 *        + The realloc'd block is ALWAYS moved.
 *        + The pointer passed to realloc() is verified in the same way that 
 *          Fortify_free() verifies pointers before it frees them.
 *        + All the Fortify_malloc() and Fortify_free() protection
 */
void *FORTIFY_STORAGE
Fortify_realloc(void *ptr, size_t new_size, char *file, unsigned long line)
{
  void *new_ptr;
  struct Header *h = (struct Header *)
      ((unsigned char *) ptr - sizeof(struct Header) -
       FORTIFY_BEFORE_SIZE);

  if (st_Disabled) {
    FORTIFY_LOCK();
    new_ptr = realloc(ptr, new_size);
    FORTIFY_UNLOCK();
    return (new_ptr);
  }

  if (!ptr)
    return (Fortify_malloc(new_size, file, line));

  FORTIFY_LOCK();

  if (!IsOnList(h)) {
    sprintf(st_Buffer,
            "\nFortify: %s.%ld\n         Invalid pointer or corrupted header passed to realloc\n",
            file, line);
    st_Output(st_Buffer);
    goto fail;
  }

  if (!CheckBlock(h, file, line))
    goto fail;

  new_ptr = Fortify_malloc(new_size, file, line);
  if (!new_ptr) {
    FORTIFY_UNLOCK();
    return (0);
  }

  if (h->Size < new_size)
    memcpy(new_ptr, ptr, h->Size);
  else
    memcpy(new_ptr, ptr, new_size);

  Fortify_free(ptr, file, line);
  FORTIFY_UNLOCK();
  return (new_ptr);

fail:
  sprintf(st_Buffer, "         realloc(%p, %ld) failed\n", ptr,
          (unsigned long) new_size);
  st_Output(st_Buffer);
  FORTIFY_UNLOCK();
  return (NULL);
}

/*
 * Fortifty_calloc() - Uses Fortify_malloc() to implement calloc(). Much
 *                     the same protection as Fortify_malloc().
 */
void *FORTIFY_STORAGE
Fortify_calloc(size_t num, size_t size, char *file, unsigned long line)
{
  void *ptr;

  ptr = Fortify_malloc(num * size, file, line);

  if (ptr)
    memset(ptr, 0, num * size);

  return (ptr);
}

/*
 * Fortify_CheckPointer() - Returns true if the uptr points to a valid
 *   piece of Fortify_malloc()'d memory. The memory must be on the malloc'd
 *   list, and it's sentinals must be in tact.
 *     If anything is wrong, an error message is issued.
 *
 *   (Note - if fortify is disabled, this function always returns true).
 */
int FORTIFY_STORAGE
Fortify_CheckPointer(void *uptr, char *file, unsigned long line)
{
  unsigned char *ptr =
      (unsigned char *) uptr - sizeof(struct Header) - FORTIFY_BEFORE_SIZE;
  int r;

  if (st_Disabled)
    return (1);

  FORTIFY_LOCK();

  if (!IsOnList((struct Header *) ptr)) {
    sprintf(st_Buffer,
            "\nFortify: %s.%ld\n         Invalid pointer or corrupted header detected (%p)\n",
            file, line, uptr);
    st_Output(st_Buffer);
    FORTIFY_UNLOCK();
    return (0);
  }

  r = CheckBlock((struct Header *) ptr, file, line);
  FORTIFY_UNLOCK();
  return r;
}

/*
 * Fortify_SetOutputFunc(OutputFuncPtr Output) - Sets the function used to
 *   output all error and diagnostic messages by fortify. The output function 
 *   takes a single unsigned char * argument, and must be able to handle newlines.
 *     The function returns the old pointer.
 */
Fortify_OutputFuncPtr FORTIFY_STORAGE
Fortify_SetOutputFunc(Fortify_OutputFuncPtr Output)
{
  OutputFuncPtr Old = st_Output;

  st_Output = (OutputFuncPtr) Output;

  return ((Fortify_OutputFuncPtr) Old);
}

/*
 * Fortify_SetMallocFailRate(int Percent) - Fortify_malloc() will make the
 *   malloc attempt fail this Percent of the time, even if the memory is
 *   available. Useful to "stress-test" an application. Returns the old
 *   value. The fail rate defaults to 0.
 */
int FORTIFY_STORAGE Fortify_SetMallocFailRate(int Percent)
{
  int Old = st_MallocFailRate;

  st_MallocFailRate = Percent;

  return (Old);
}


/*
 * Fortify_CheckAllMemory() - Checks the sentinals of all malloc'd memory.
 *   Returns the number of blocks that failed. 
 *
 *  (If Fortify is disabled, this function always returns 0).
 */
int FORTIFY_STORAGE Fortify_CheckAllMemory(char *file, unsigned long line)
{
  struct Header *curr = st_Head;
  int count = 0;

  if (st_Disabled)
    return (0);

  FORTIFY_LOCK();

  while (curr) {
    if (!CheckBlock(curr, file, line))
      count++;

    curr = curr->Next;
  }

  if (file) {
    st_LastVerifiedFile = file;
    st_LastVerifiedLine = line;
  }

  FORTIFY_UNLOCK();
  return (count);
}

/* Fortify_EnterScope - enters a new Fortify scope level. 
 * returns the new scope level.
 */
int FORTIFY_STORAGE Fortify_EnterScope(char *file, unsigned long line)
{
  return (++st_Scope);
}

/* Fortify_LeaveScope - leaves a Fortify scope level,
 * also prints a memory dump of all non-freed memory that was allocated
 * during the scope being exited.
 */
int FORTIFY_STORAGE Fortify_LeaveScope(char *file, unsigned long line)
{
  struct Header *curr = st_Head;
  int count = 0;
  unsigned long size = 0;

  if (st_Disabled)
    return (0);

  FORTIFY_LOCK();

  st_Scope--;
  while (curr) {
    if (curr->Scope > st_Scope) {
      if (count == 0) {
        sprintf(st_Buffer, "\nFortify: Memory Dump at %s.%ld\n", file,
                line);
        st_Output(st_Buffer);
        OutputLastVerifiedPoint();
        sprintf(st_Buffer, "%11s %8s %s\n", "Address", "Size",
                "Allocator");
        st_Output(st_Buffer);
      }

      OutputHeader(curr);
      count++;
      size += curr->Size;
    }

    curr = curr->Next;
  }

  if (count) {
    sprintf(st_Buffer, "%11s %8ld bytes overhead\n", "and",
            (unsigned long) (count *
                             (sizeof(struct Header) + FORTIFY_BEFORE_SIZE +
                              FORTIFY_AFTER_SIZE)));
    st_Output(st_Buffer);

    sprintf(st_Buffer, "%11s %8ld bytes in %d blocks\n", "total", size,
            count);
    st_Output(st_Buffer);
  }

  FORTIFY_UNLOCK();
  return (count);
}

/*
 * Fortify_OutputAllMemory() - Outputs the entire list of currently
 *     malloc'd memory. For each malloc'd block is output it's Address,
 *   Size, and the SourceFile and Line that allocated it.
 *
 *   If there is no memory on the list, this function outputs nothing.
 *
 *   It returns the number of blocks on the list, unless fortify has been
 *   disabled, in which case it always returns 0.
 */
int FORTIFY_STORAGE Fortify_OutputAllMemory(char *file, unsigned long line)
{
  struct Header *curr = st_Head;
  int count = 0;
  unsigned long size = 0;

  if (st_Disabled)
    return (0);

  FORTIFY_LOCK();

  if (curr) {
    sprintf(st_Buffer, "\nFortify: Memory Dump at %s.%ld\n", file, line);
    st_Output(st_Buffer);
    OutputLastVerifiedPoint();
    sprintf(st_Buffer, "%11s %8s %s\n", "Address", "Size", "Allocator");
    st_Output(st_Buffer);

    while (curr) {
      OutputHeader(curr);
      count++;
      size += curr->Size;
      curr = curr->Next;
    }

    sprintf(st_Buffer, "%11s %8ld bytes overhead\n", "and",
            (unsigned long) (count *
                             (sizeof(struct Header) + FORTIFY_BEFORE_SIZE +
                              FORTIFY_AFTER_SIZE)));
    st_Output(st_Buffer);

    sprintf(st_Buffer, "%11s %8ld bytes in %d blocks\n", "total", size,
            count);
    st_Output(st_Buffer);
  }

  FORTIFY_UNLOCK();
  return (count);
}

/* Fortify_DumpAllMemory(Scope) - Outputs the entire list of currently
 * new'd memory within the specified scope. For each new'd block is output
 * it's Address, Size, the SourceFile and Line that allocated it, a hex dump
 * of the contents of the memory and an ascii dump of printable characters.
 *
 * If there is no memory on the list, this function outputs nothing.
 *
 * It returns the number of blocks on the list, unless Fortify has been
 * disabled, in which case it always returns 0.
 */
int FORTIFY_STORAGE
Fortify_DumpAllMemory(int scope, char *file, unsigned long line)
{
  struct Header *curr = st_Head;
  int count = 0;
  unsigned long size = 0;

  if (st_Disabled)
    return (0);

  FORTIFY_LOCK();

  while (curr) {
    if (curr->Scope >= scope) {
      if (count == 0) {
        sprintf(st_Buffer, "\nFortify: Memory Dump at %s.%ld\n", file,
                line);
        st_Output(st_Buffer);
        OutputLastVerifiedPoint();
        sprintf(st_Buffer, "%11s %8s %s\n", "Address", "Size",
                "Allocator");
        st_Output(st_Buffer);
      }

      OutputHeader(curr);
      OutputMemory(curr);
      st_Output("\n");
      count++;
      size += curr->Size;
    }

    curr = curr->Next;
  }

  if (count) {
    sprintf(st_Buffer, "%11s %8ld bytes overhead\n", "and",
            (unsigned long) (count *
                             (sizeof(struct Header) + FORTIFY_BEFORE_SIZE +
                              FORTIFY_AFTER_SIZE)));
    st_Output(st_Buffer);

    sprintf(st_Buffer, "%11s %8ld bytes in %d blocks\n", "total", size,
            count);
    st_Output(st_Buffer);
  }

  FORTIFY_UNLOCK();
  return (count);
}

/*
 * Fortify_Disable() - This function provides a mechanism to disable Fortify
 *   without recompiling all the sourcecode. It can only be called, though,
 *   when there is no memory on the Fortify malloc'd list. (Ideally, at the 
 *   start of the program before any memory has been allocated). If you
 *   call this function when there IS memory on the Fortify malloc'd list,
 *   it will issue an error, and fortify will not be disabled.
 */
int FORTIFY_STORAGE Fortify_Disable(char *file, unsigned long line)
{
  int result;
  FORTIFY_LOCK();

  if (st_Head) {
    sprintf(st_Buffer, "Fortify: %s.%d\n", file, (int) line);
    st_Output(st_Buffer);
    st_Output("         Fortify_Disable failed\n");
    st_Output
        ("         (because there is memory on the Fortify memory list)\n");

    Fortify_OutputAllMemory(file, line);
    result = 0;
  } else {
    st_Disabled = 1;
    result = 1;
  }

  FORTIFY_UNLOCK();
  return (result);
}

/* 
 * Check a block's header and fortifications.
 */
static int CheckBlock(struct Header *h, char *file, unsigned long line)
{
  unsigned char *ptr = (unsigned char *) h;
  int result = 1;

  if (!IsHeaderValid(h)) {
    sprintf(st_Buffer,
            "\nFortify: %s.%ld\n         Invalid pointer or corrupted header detected (%p)\n",
            file, line, ptr + sizeof(struct Header) + FORTIFY_BEFORE_SIZE);
    st_Output(st_Buffer);
    OutputLastVerifiedPoint();
    return (0);
  }

  if (!CheckFortification(ptr + sizeof(struct Header),
                          FORTIFY_BEFORE_VALUE, FORTIFY_BEFORE_SIZE)) {
    sprintf(st_Buffer,
            "\nFortify: %s.%ld\n         Memory overrun detected before block\n",
            file, line);
    st_Output(st_Buffer);

    sprintf(st_Buffer, "         (%p,%ld,%s.%ld)\n",
            ptr + sizeof(struct Header) + FORTIFY_BEFORE_SIZE,
            (unsigned long) h->Size, h->File, h->Line);
    st_Output(st_Buffer);

    OutputFortification(ptr + sizeof(struct Header),
                        FORTIFY_BEFORE_VALUE, FORTIFY_BEFORE_SIZE);
    OutputLastVerifiedPoint();
    result = 0;
  }

  if (!CheckFortification
      (ptr + sizeof(struct Header) + FORTIFY_BEFORE_SIZE + h->Size,
       FORTIFY_AFTER_VALUE, FORTIFY_AFTER_SIZE)) {
    sprintf(st_Buffer,
            "\nFortify: %s.%ld\n         Memory overrun detected after block\n",
            file, line);
    st_Output(st_Buffer);

    sprintf(st_Buffer, "         (%p,%ld,%s.%ld)\n",
            ptr + sizeof(struct Header) + FORTIFY_BEFORE_SIZE,
            (unsigned long) h->Size, h->File, h->Line);
    st_Output(st_Buffer);

    OutputFortification(ptr + sizeof(struct Header) + FORTIFY_BEFORE_SIZE +
                        h->Size, FORTIFY_AFTER_VALUE, FORTIFY_AFTER_SIZE);
    OutputLastVerifiedPoint();
    result = 0;
  }

  return (result);
}

/*
 * Checks if the _size_ bytes from _ptr_ are all set to _value_
 */
static int CheckFortification(unsigned char *ptr, unsigned char value,
                              size_t size)
{
  while (size--)
    if (*ptr++ != value)
      return (0);

  return (1);
}

/*
 * Set the _size_ bytes from _ptr_ to _value_.
 */
static void SetFortification(unsigned char *ptr, unsigned char value,
                             size_t size)
{
  memset(ptr, value, size);
}

/*
 * Output the corrupted section of the fortification 
 */
/* Output the corrupted section of the fortification */
static void
OutputFortification(unsigned char *ptr, unsigned char value, size_t size)
{
  unsigned long offset, column;
  char ascii[17];

  st_Output("Address     Offset Data");

  offset = 0;
  column = 0;

  while (offset < size) {
    if (column == 0) {
      sprintf(st_Buffer, "\n%8p %8d ", ptr, (int) offset);
      st_Output(st_Buffer);
    }

    sprintf(st_Buffer, "%02x ", *ptr);
    st_Output(st_Buffer);

    ascii[column] = isprint(*ptr) ? (char) (*ptr) : (char) (' ');
    ascii[column + 1] = '\0';

    ptr++;
    offset++;
    column++;

    if (column == 16) {
      st_Output("   \"");
      st_Output(ascii);
      st_Output("\"");
      column = 0;
    }
  }

  if (column != 0) {
    while (column++ < 16) {
      st_Output("   ");
    }
    st_Output("   \"");
    st_Output(ascii);
    st_Output("\"");
  }

  st_Output("\n");
}

/*
 * Returns true if the supplied pointer does indeed point to a real Header
 */
static int IsHeaderValid(struct Header *h)
{
  return (!ChecksumHeader(h));
}

/*
 * Updates the checksum to make the header valid
 */
static void MakeHeaderValid(struct Header *h)
{
  h->Checksum = 0;
  h->Checksum = -ChecksumHeader(h);
}

/*
 * Calculate (and return) the checksum of the header. (Including the Checksum
 * variable itself. If all is well, the checksum returned by this function should
 * be 0.
 */
static int ChecksumHeader(struct Header *h)
{
  int c, checksum, *p;

  for (c = 0, checksum = 0, p = (int *) h;
       c < sizeof(struct Header) / sizeof(int); c++)
    checksum += *p++;

  return (checksum);
}

/* 
 * Examines the malloc'd list to see if the given header is on it.
 */
static int IsOnList(struct Header *h)
{
  struct Header *curr;

  curr = st_Head;
  while (curr) {
    if (curr == h)
      return (1);

    curr = curr->Next;
  }

  return (0);
}

/*
 * Hex and ascii dump the memory
 */
static void OutputMemory(struct Header *h)
{
  OutputFortification((unsigned char *) h + sizeof(struct Header) +
                      FORTIFY_BEFORE_SIZE, 0, h->Size);
}


/*
 * Output the header...
 */
static void OutputHeader(struct Header *h)
{
  sprintf(st_Buffer, "%11p %8ld %s.%ld (%d)\n",
          (unsigned char *) h + sizeof(struct Header) +
          FORTIFY_BEFORE_SIZE, (unsigned long) h->Size, h->File, h->Line,
          h->Scope);
  st_Output(st_Buffer);
}

static void OutputLastVerifiedPoint()
{
  sprintf(st_Buffer, "\nLast Verified point: %s.%ld\n",
          st_LastVerifiedFile, st_LastVerifiedLine);
  st_Output(st_Buffer);
}


#endif                          /* FORTIFY */