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/* Copyright (C) 2004, 2005 Free Software Foundation.
Ensure builtin __strcat_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 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);
#define RESET_DST_WITH(FILLER) \
do { memset (dst, 'X', sizeof (dst)); strcpy (dst, (FILLER)); } while (0)
#include "chk.h"
const char s1[] = "123";
char p[32] = "";
char *s2 = "defg";
char *s3 = "FGH";
char *s4;
size_t l1 = 1;
char *s5;
void
__attribute__((noinline))
test1 (void)
{
const char *const x1 = "hello world";
const char *const x2 = "";
char dst[64], *d2;
chk_calls = 0;
strcat_disallowed = 1;
/* Following strcat calls should be optimized out at compile time. */
RESET_DST_WITH (x1);
if (strcat (dst, "") != dst || strcmp (dst, x1))
abort ();
RESET_DST_WITH (x1);
if (strcat (dst, x2) != dst || strcmp (dst, x1))
abort ();
RESET_DST_WITH (x1); d2 = dst;
if (strcat (++d2, x2) != dst+1 || d2 != dst+1 || strcmp (dst, x1))
abort ();
RESET_DST_WITH (x1); d2 = dst;
if (strcat (++d2+5, x2) != dst+6 || d2 != dst+1 || strcmp (dst, x1))
abort ();
RESET_DST_WITH (x1); d2 = dst;
if (strcat (++d2+5, x1+11) != dst+6 || d2 != dst+1 || strcmp (dst, x1))
abort ();
if (chk_calls)
abort ();
strcat_disallowed = 0;
RESET_DST_WITH (x1);
if (strcat (dst, " 1111") != dst
|| memcmp (dst, "hello world 1111\0XXX", 20))
abort ();
RESET_DST_WITH (x1);
if (strcat (dst+5, " 2222") != dst+5
|| memcmp (dst, "hello world 2222\0XXX", 20))
abort ();
RESET_DST_WITH (x1); d2 = dst;
if (strcat (++d2+5, " 3333") != dst+6 || d2 != dst+1
|| memcmp (dst, "hello world 3333\0XXX", 20))
abort ();
RESET_DST_WITH (x1);
strcat (strcat (strcat (strcat (strcat (strcat (dst, ": this "), ""),
"is "), "a "), "test"), ".");
if (memcmp (dst, "hello world: this is a test.\0X", 30))
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. */
RESET_DST_WITH (x1);
if (__builtin_strcat (dst, "") != dst || strcmp (dst, x1))
abort ();
if (chk_calls)
abort ();
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
- source length is not known, but destination is. */
memset (&a, '\0', sizeof (a));
s5 = (char *) &a;
__asm __volatile ("" : : "r" (s5) : "memory");
chk_calls = 0;
strcat (a.buf1 + 2, s3 + 3);
strcat (r, s3 + 2);
r = l1 == 1 ? __builtin_alloca (4) : &a.buf2[7];
memset (r, '\0', 3);
__asm __volatile ("" : : "r" (r) : "memory");
strcat (r, s2 + 2);
strcat (r + 2, s3 + 3);
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];
}
strcat (r, s2 + 4);
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");
strcat (a.buf1 + 2, "a");
strcat (r, "");
r = l1 == 1 ? __builtin_alloca (4) : &a.buf2[7];
memset (r, '\0', 3);
__asm __volatile ("" : : "r" (r) : "memory");
strcat (r, s1 + 1);
if (chk_calls != 2)
abort ();
chk_calls = 0;
/* Unknown destination and source, no checking. */
strcat (s4, s3);
if (chk_calls)
abort ();
chk_calls = 0;
}
/* 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)
{
strcat (&a.buf2[9], s2 + 3);
abort ();
}
if (__builtin_setjmp (chk_fail_buf) == 0)
{
strcat (&a.buf2[7], s3 + strlen (s3) - 3);
abort ();
}
if (__builtin_setjmp (chk_fail_buf) == 0)
{
strcat (&buf3[19], "a");
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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