[feat] OpenBSD pledge

README.md

@@ -5,6 +5,7 @@ azan
 - standalone nasm
 - unix portable syscalls
 - tested on Linux, OpenBSD, FreeBSD and NetBSD
+- OpenBSD pledge.
 - binary size ≈ 7 kb
 - instructions ≈ 250-400
 - branches ≈ 6-20

azan.s

@@ -39,6 +39,8 @@ section .rodata
 	usage_len:	equ $ - usage_msg
 	version_msg:	db "azan-", VERSION, 10, 0
 	version_len:	equ $ - version_msg
+	pledge_msg:	db "pledge", 10, 0
+	promises:	db "stdio", 0
 
 section .data
 	res_msg:	db "X XX:XX", 10, 0
@@ -84,6 +86,7 @@ check_argv:
 	DIE	version_msg, version_len
 
 get_timestamp:
+	OPENBSD_PLEDGE
 	mov	rax, SYS_gettimeofday	;sys_gettimeofday(
 	mov	rdi, tmp0		;struct timeval *tv,
 	mov	rsi, rsi		;struct timezone* tz
@@ -456,6 +459,8 @@ print_all_12:
 	PRINT_HM
 	EEXIT	EXIT_SUCCESS
 
+die_pledge:
+	DIE	pledge_msg, 8
 ;	result_hour	;r8
 ;	result_min	;r9
 ;	duhr_ts:	;xmm0

macros.s

@@ -25,6 +25,17 @@ section .note.openbsd.ident note
 %endif
 %endmacro
 
+%macro OPENBSD_PLEDGE 0
+%ifdef OpenBSD
+	mov	rax, SYS_pledge	;pledge(
+	mov	rdi, promises	;const char *promises
+	xor	rsi, rsi	;const char *execpromises
+	syscall
+	cmp	rax, 0
+	jl	die_pledge
+%endif
+%endmacro
+
 %macro EEXIT 1
 	mov rax, SYS_exit
 	mov rdi, %1

syscalls.s

@@ -11,6 +11,7 @@
 	%define SYS_exit 1
 	%define SYS_write 4
 	%define SYS_gettimeofday 67
+	%define SYS_pledge 108
 %elifdef FreeBSD
 	%define SYS_exit 1
 	%define SYS_write 4