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/* Copyright (C) 2004, 2005 Free Software Foundation.
Ensure builtin __strncat_chk performs correctly. */
extern void abort (void);
typedef __SIZE_TYPE__ size_t;
extern size_t strlen (const char *);
extern void *memcpy (void *, const void *, size_t);
extern char *strcat (char *, const char *);
extern char *strncat (char *, const char *, size_t);
extern int memcmp (const void *, const void *, size_t);
extern char *strcpy (char *, const char *);
extern int strcmp (const char *, const char *);
extern void *memset (void *, int, size_t);
#include "chk.h"
const char s1[] = "123";
char p[32] = "";
char *s2 = "defg";
char *s3 = "FGH";
char *s4;
size_t l1 = 1;
char *s5;
int x = 123;
void
__attribute__((noinline))
test1 (void)
{
const char *const s1 = "hello world";
const char *const s2 = "";
const char *s3;
char dst[64], *d2;
/* Following strncat calls should be all optimized out. */
chk_calls = 0;
strncat_disallowed = 1;
strcat_disallowed = 1;
strcpy (dst, s1);
if (strncat (dst, "", 100) != dst || strcmp (dst, s1))
abort ();
strcpy (dst, s1);
if (strncat (dst, s2, 100) != dst || strcmp (dst, s1))
abort ();
strcpy (dst, s1); d2 = dst;
if (strncat (++d2, s2, 100) != dst+1 || d2 != dst+1 || strcmp (dst, s1))
abort ();
strcpy (dst, s1); d2 = dst;
if (strncat (++d2+5, s2, 100) != dst+6 || d2 != dst+1 || strcmp (dst, s1))
abort ();
strcpy (dst, s1); d2 = dst;
if (strncat (++d2+5, s1+11, 100) != dst+6 || d2 != dst+1 || strcmp (dst, s1))
abort ();
strcpy (dst, s1); d2 = dst;
if (strncat (++d2+5, s1, 0) != dst+6 || d2 != dst+1 || strcmp (dst, s1))
abort ();
strcpy (dst, s1); d2 = dst; s3 = s1;
if (strncat (++d2+5, ++s3, 0) != dst+6 || d2 != dst+1 || strcmp (dst, s1)
|| s3 != s1 + 1)
abort ();
strcpy (dst, s1); d2 = dst;
if (strncat (++d2+5, "", ++x) != dst+6 || d2 != dst+1 || x != 124
|| strcmp (dst, s1))
abort ();
if (chk_calls)
abort ();
strcat_disallowed = 0;
/* These __strncat_chk calls should be optimized into __strcat_chk,
as strlen (src) <= len. */
strcpy (dst, s1);
if (strncat (dst, "foo", 3) != dst || strcmp (dst, "hello worldfoo"))
abort ();
strcpy (dst, s1);
if (strncat (dst, "foo", 100) != dst || strcmp (dst, "hello worldfoo"))
abort ();
strcpy (dst, s1);
if (strncat (dst, s1, 100) != dst || strcmp (dst, "hello worldhello world"))
abort ();
if (chk_calls != 3)
abort ();
chk_calls = 0;
/* The following calls have side-effects in dest, so are not checked. */
strcpy (dst, s1); d2 = dst;
if (__builtin___strncat_chk (++d2, s1, 100, os (++d2)) != dst+1
|| d2 != dst+1 || strcmp (dst, "hello worldhello world"))
abort ();
strcpy (dst, s1); d2 = dst;
if (__builtin___strncat_chk (++d2+5, s1, 100, os (++d2+5)) != dst+6
|| d2 != dst+1 || strcmp (dst, "hello worldhello world"))
abort ();
strcpy (dst, s1); d2 = dst;
if (__builtin___strncat_chk (++d2+5, s1+5, 100, os (++d2+5)) != dst+6
|| d2 != dst+1 || strcmp (dst, "hello world world"))
abort ();
if (chk_calls)
abort ();
chk_calls = 0;
strcat_disallowed = 1;
/* Test at least one instance of the __builtin_ style. We do this
to ensure that it works and that the prototype is correct. */
strcpy (dst, s1);
if (__builtin_strncat (dst, "", 100) != dst || strcmp (dst, s1))
abort ();
if (chk_calls)
abort ();
strncat_disallowed = 0;
strcat_disallowed = 0;
}
/* Test whether compile time checking is done where it should
and so is runtime object size checking. */
void
__attribute__((noinline))
test2 (void)
{
struct A { char buf1[10]; char buf2[10]; } a;
char *r = l1 == 1 ? &a.buf1[5] : &a.buf2[4];
char buf3[20];
int i;
/* The following calls should do runtime checking. */
memset (&a, '\0', sizeof (a));
s5 = (char *) &a;
__asm __volatile ("" : : "r" (s5) : "memory");
chk_calls = 0;
strncat (a.buf1 + 2, s3 + 3, l1 - 1);
strncat (r, s3 + 2, l1);
r = l1 == 1 ? __builtin_alloca (4) : &a.buf2[7];
memset (r, '\0', 3);
__asm __volatile ("" : : "r" (r) : "memory");
strncat (r, s2 + 2, l1 + 1);
strncat (r + 2, s3 + 3, l1 - 1);
r = buf3;
for (i = 0; i < 4; ++i)
{
if (i == l1 - 1)
r = &a.buf1[1];
else if (i == l1)
r = &a.buf2[7];
else if (i == l1 + 1)
r = &buf3[5];
else if (i == l1 + 2)
r = &a.buf1[9];
}
strncat (r, s2 + 4, l1);
if (chk_calls != 5)
abort ();
/* Following have known destination and known source length,
but we don't know the length of dest string, so runtime checking
is needed too. */
memset (&a, '\0', sizeof (a));
chk_calls = 0;
s5 = (char *) &a;
__asm __volatile ("" : : "r" (s5) : "memory");
strncat (a.buf1 + 2, "a", 5);
strncat (r, "def", 0);
r = l1 == 1 ? __builtin_alloca (4) : &a.buf2[7];
memset (r, '\0', 3);
__asm __volatile ("" : : "r" (r) : "memory");
strncat (r, s1 + 1, 2);
if (chk_calls != 2)
abort ();
chk_calls = 0;
strcat_disallowed = 1;
/* Unknown destination and source, no checking. */
strncat (s4, s3, l1 + 1);
strcat_disallowed = 0;
if (chk_calls)
abort ();
}
/* Test whether runtime and/or compile time checking catches
buffer overflows. */
void
__attribute__((noinline))
test3 (void)
{
struct A { char buf1[10]; char buf2[10]; } a;
char buf3[20];
memset (&a, '\0', sizeof (a));
memset (buf3, '\0', sizeof (buf3));
s5 = (char *) &a;
__asm __volatile ("" : : "r" (s5) : "memory");
s5 = buf3;
__asm __volatile ("" : : "r" (s5) : "memory");
chk_fail_allowed = 1;
/* Runtime checks. */
if (__builtin_setjmp (chk_fail_buf) == 0)
{
strncat (&a.buf2[9], s2 + 3, 4);
abort ();
}
if (__builtin_setjmp (chk_fail_buf) == 0)
{
strncat (&a.buf2[7], s3 + strlen (s3) - 3, 3);
abort ();
}
if (__builtin_setjmp (chk_fail_buf) == 0)
{
strncat (&buf3[19], "abcde", 1);
abort ();
}
chk_fail_allowed = 0;
}
void
main_test (void)
{
#ifndef __OPTIMIZE__
/* Object size checking is only intended for -O[s123]. */
return;
#endif
__asm ("" : "=r" (s2) : "0" (s2));
__asm ("" : "=r" (s3) : "0" (s3));
__asm ("" : "=r" (l1) : "0" (l1));
s4 = p;
test1 ();
memset (p, '\0', sizeof (p));
test2 ();
test3 ();
}
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