ladybird/Libraries/LibELF/AuxiliaryVector.h
Andrew Kaster f96b827990 Kernel+LibELF: Expose ELF Auxiliary Vector to Userspace
The AT_* entries are placed after the environment variables, so that
they can be found by iterating until the end of the envp array, and then
going even further beyond :^)
2020-07-07 10:38:54 +02:00

116 lines
4.8 KiB
C

/*
* Copyright (c) 2020, The SerenityOS developers.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
/* Auxiliary Vector types, from Intel386 ABI ver 1.0 section 2.3.3 */
typedef struct
{
long a_type; /* Note: Extended to long from int, for ease of comaptibility w/64 bit */
union {
long a_val;
void* a_ptr;
void (*a_fnc)(); /* In spec, not used */
} a_un;
} auxv_t;
#define AT_NULL 0 /* No length, last entry's a_type has this value */
#define AT_IGNORE 1 /* Entry has no meaning, a_un undefined */
#define AT_EXECFD 2 /* a_val contains a file descriptor of the main program image */
#define AT_PHDR 3 /* a_ptr contains pointer to program header table of main program image */
#define AT_PHENT 4 /* a_val holds size of program header table entries */
#define AT_PHNUM 5 /* a_val holds number of program header table entries */
#define AT_PAGESZ 6 /* a_val gives system page size in bytes */
#define AT_BASE 7 /* a_ptr holds base address that Loader was loaded into memory */
#define AT_FLAGS 8 /* a_val holds 1 bit flags. Undefined flags are 0 */
#define AT_ENTRY 9 /* a_ptr holds entry point of application for loader */
#define AT_NOTELF 10 /* a_val non-zero if the program is not ELF */
#define AT_UID 11 /* a_val holds real user id of process */
#define AT_EUID 12 /* a_val holds effective user id of process */
#define AT_GID 13 /* a_val holds real group id of process */
#define AT_EGID 14 /* a_val holds effective group id of process */
#define AT_PLATFORM 15 /* a_val points to a string containing platform name */
#define AT_HWCAP 16 /* a_val contains bitmask of CPU features. Equivalent to CPUID 1.EDX*/
#define AT_CLKTCK 17 /* a_val contains frequence at which times() increments. (Re: Spec. What is times()?) */
#define AT_SECURE 23 /* a_val holds 1 if program in secure mode (e.g. suid). Otherwise 0 */
#define AT_BASE_PLATFORM 24 /* a_ptr points to a string identifying base platform name, which might be different from platform (e.g x86_64 when in i386 compat) */
#define AT_RANDOM 25 /* a_ptr points to 16 securely generated random bytes */
#define AT_HWCAP2 26 /* a_val holds extended hw feature mask. Currently 0 */
#define AT_EXECFN 31 /* a_ptr points to file name of executed program */
#ifdef __cplusplus
# include <AK/String.h>
# include <AK/Types.h>
struct AuxiliaryValue {
enum Type {
Null = AT_NULL,
Ignore = AT_IGNORE,
ExecFileDescriptor = AT_EXECFD,
Phdr = AT_PHDR,
Phent = AT_PHENT,
Phnum = AT_PHNUM,
PageSize = AT_PAGESZ,
BaseAddress = AT_BASE,
Flags = AT_FLAGS,
Entry = AT_ENTRY,
NotELF = AT_NOTELF,
Uid = AT_UID,
EUid = AT_EUID,
Gid = AT_GID,
EGid = AT_EGID,
Platform = AT_PLATFORM,
HwCap = AT_HWCAP,
ClockTick = AT_CLKTCK,
Secure = AT_SECURE,
BasePlatform = AT_BASE_PLATFORM,
Random = AT_RANDOM,
HwCap2 = AT_HWCAP2,
ExecFilename = AT_EXECFN
};
AuxiliaryValue(Type type, long val)
{
auxv.a_type = type;
auxv.a_un.a_val = val;
}
AuxiliaryValue(Type type, void* ptr)
{
auxv.a_type = type;
auxv.a_un.a_ptr = (void*)ptr;
}
AuxiliaryValue(Type type, String string)
{
auxv.a_type = type;
auxv.a_un.a_ptr = nullptr;
optional_string = string;
}
auxv_t auxv {};
String optional_string;
};
#endif /* __cplusplus */