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/* Copyright (C) 2004, 2005 Free Software Foundation.
Ensure builtin __strcpy_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 *strcpy (char *, const char *);
extern int memcmp (const void *, const void *, size_t);
#include "chk.h"
const char s1[] = "123";
char p[32] = "";
char *s2 = "defg";
char *s3 = "FGH";
char *s4;
size_t l1 = 1;
void
__attribute__((noinline))
test1 (void)
{
chk_calls = 0;
#ifndef __OPTIMIZE_SIZE__
strcpy_disallowed = 1;
#else
strcpy_disallowed = 0;
#endif
if (strcpy (p, "abcde") != p || memcmp (p, "abcde", 6))
abort ();
if (strcpy (p + 16, "vwxyz" + 1) != p + 16 || memcmp (p + 16, "wxyz", 5))
abort ();
if (strcpy (p + 1, "") != p + 1 || memcmp (p, "a\0cde", 6))
abort ();
if (strcpy (p + 3, "fghij") != p + 3 || memcmp (p, "a\0cfghij", 9))
abort ();
/* Test at least one instance of the __builtin_ style. We do this
to ensure that it works and that the prototype is correct. */
if (__builtin_strcpy (p, "abcde") != p || memcmp (p, "abcde", 6))
abort ();
strcpy_disallowed = 0;
if (chk_calls)
abort ();
}
#ifndef MAX_OFFSET
#define MAX_OFFSET (sizeof (long long))
#endif
#ifndef MAX_COPY
#define MAX_COPY (10 * sizeof (long long))
#endif
#ifndef MAX_EXTRA
#define MAX_EXTRA (sizeof (long long))
#endif
#define MAX_LENGTH (MAX_OFFSET + MAX_COPY + 1 + MAX_EXTRA)
/* Use a sequence length that is not divisible by two, to make it more
likely to detect when words are mixed up. */
#define SEQUENCE_LENGTH 31
static union {
char buf[MAX_LENGTH];
long long align_int;
long double align_fp;
} u1, u2;
void
__attribute__((noinline))
test2 (void)
{
int off1, off2, len, i;
char *p, *q, c;
for (off1 = 0; off1 < MAX_OFFSET; off1++)
for (off2 = 0; off2 < MAX_OFFSET; off2++)
for (len = 1; len < MAX_COPY; len++)
{
for (i = 0, c = 'A'; i < MAX_LENGTH; i++, c++)
{
u1.buf[i] = 'a';
if (c >= 'A' + SEQUENCE_LENGTH)
c = 'A';
u2.buf[i] = c;
}
u2.buf[off2 + len] = '\0';
p = strcpy (u1.buf + off1, u2.buf + off2);
if (p != u1.buf + off1)
abort ();
q = u1.buf;
for (i = 0; i < off1; i++, q++)
if (*q != 'a')
abort ();
for (i = 0, c = 'A' + off2; i < len; i++, q++, c++)
{
if (c >= 'A' + SEQUENCE_LENGTH)
c = 'A';
if (*q != c)
abort ();
}
if (*q++ != '\0')
abort ();
for (i = 0; i < MAX_EXTRA; i++, q++)
if (*q != 'a')
abort ();
}
}
/* Test whether compile time checking is done where it should
and so is runtime object size checking. */
void
__attribute__((noinline))
test3 (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;
const char *l;
/* The following calls should do runtime checking
- source length is not known, but destination is. */
chk_calls = 0;
strcpy (a.buf1 + 2, s3 + 3);
strcpy (r, s3 + 2);
r = l1 == 1 ? __builtin_alloca (4) : &a.buf2[7];
strcpy (r, s2 + 2);
strcpy (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];
}
strcpy (r, s2 + 4);
if (chk_calls != 5)
abort ();
/* Following have known destination and known source length,
so if optimizing certainly shouldn't result in the checking
variants. */
chk_calls = 0;
strcpy (a.buf1 + 2, "");
strcpy (r, "a");
r = l1 == 1 ? __builtin_alloca (4) : &a.buf2[7];
strcpy (r, s1 + 1);
r = buf3;
l = "abc";
for (i = 0; i < 4; ++i)
{
if (i == l1 - 1)
r = &a.buf1[1], l = "e";
else if (i == l1)
r = &a.buf2[7], l = "gh";
else if (i == l1 + 1)
r = &buf3[5], l = "jkl";
else if (i == l1 + 2)
r = &a.buf1[9], l = "";
}
strcpy (r, "");
/* Here, strlen (l) + 1 is known to be at most 4 and
__builtin_object_size (&buf3[16], 0) is 4, so this doesn't need
runtime checking. */
strcpy (&buf3[16], l);
/* Unknown destination and source, no checking. */
strcpy (s4, s3);
if (chk_calls)
abort ();
chk_calls = 0;
}
/* Test whether runtime and/or compile time checking catches
buffer overflows. */
void
__attribute__((noinline))
test4 (void)
{
struct A { char buf1[10]; char buf2[10]; } a;
char buf3[20];
chk_fail_allowed = 1;
/* Runtime checks. */
if (__builtin_setjmp (chk_fail_buf) == 0)
{
strcpy (&a.buf2[9], s2 + 3);
abort ();
}
if (__builtin_setjmp (chk_fail_buf) == 0)
{
strcpy (&a.buf2[7], s3 + strlen (s3) - 3);
abort ();
}
/* This should be detectable at compile time already. */
if (__builtin_setjmp (chk_fail_buf) == 0)
{
strcpy (&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));
test1 ();
test2 ();
s4 = p;
test3 ();
test4 ();
}
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