newlib/winsup/cygwin/sec_posixacl.h
David Allsopp acfc63b0cf Fix invalid acl_entry_t on 32-bit Cygwin
If the acl_t struct was at or above 0x80000000 then the pointer was
sign-extended to 0xffff_ffff_8000_0000 and so the index was lost.

Signed-off-by: David Allsopp <david.allsopp@metastack.com>
2020-07-10 10:29:47 +02:00

69 lines
2.0 KiB
C

/* sec_posixacl.h: Internal definitions for POSIX ACLs.
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#include <cygwin/acl.h>
#include <sys/acl.h>
#include <acl/libacl.h>
/* Magic marker for acl_t. */
#define ACL_MAGIC (0xacdccdcadcaccacdULL)
/* Only used internally as a_type for deleted entries. */
#define ACL_DELETED_TAG (0xffff)
/* Only used internally from acl_to_text/acl_to_any_text. */
#define TEXT_END_SEPARATOR (0x1000)
#define TEXT_IS_POSIX (0x2000)
/* Internal ACL representation. */
struct __acl_t
{
uint64_t magic; /* Must be ACL_MAGIC. */
uint16_t max_count; /* Max. number of entries. */
uint16_t count; /* Number of used entries. */
uint16_t deleted; /* Number of used but deleted entries. */
uint16_t next; /* Next entry to be returned by acl_get_entry. */
aclent_t *entry; /* Pointer to variable array of ACL entries. */
};
inline acl_entry_t
__to_entry (acl_t acl, uint16_t idx)
{
return ((uint64_t) idx << 48) | (uint64_t) ((uintptr_t) acl);
}
#define __to_permset(a,i) ((acl_permset_t)__to_entry((a),(i)))
inline acl_t
__from_entry (acl_entry_t entry_d, uint16_t &idx)
{
idx = entry_d >> 48;
acl_t acl = (acl_t) (entry_d & ~((uint64_t) 0xffff << 48));
if (acl->magic != ACL_MAGIC)
return NULL;
if (idx >= acl->count)
return NULL;
if (acl->entry[idx].a_type == ACL_DELETED_TAG)
return NULL;
return acl;
}
#define __from_permset(p,i) __from_entry((acl_permset_t)(p),(i))
/* External (but opaque) ACL representation. */
struct __acl_ext_t
{
uint16_t count; /* Number of used entries. */
aclent_t entry[0]; /* Variable array of ACL entries. */
};
/* Shared functions defined in sec_acl.cc. */
mode_t __aclcalcmask (aclent_t *, int);
int __aclsort (int, aclent_t *);
int __aclcheck (aclent_t *, int, int *, bool);
char *__acltotext (aclent_t *, int, const char *, char, int);
void *__aclfromtext (const char *, int *, bool);