rust-teeny-nostd: compare with asm

2026-06-16 23:44:41 +02:00
parent aabd7b9d84
commit d2a5ce6e30
3 changed files with 76 additions and 2 deletions
@@ -0,0 +1,60 @@
+.intel_syntax noprefix
+.globl main
+
+.section .rodata
+SHELLCODE: .ascii "\x31\xC0\xFF\xC0\x89\xC7\x48\x8D\x35\x08\x00\x00\x00\xBA\x0E\x00\x00\x00\x0F\x05\xC3Hello, World!\n"
+SHELLCODE_end:
+
+SHELLCODE_len = SHELLCODE_end - SHELLCODE
+
+#define PROT_READ 0x1
+#define PROT_WRITE 0x2
+#define PROT_EXEC 0x4
+
+#define MAP_PRIVATE 0x2
+#define MAP_ANONYMOUS 0x20
+
+#define MAP_FAILED -1
+
+.section .text
+main:
+    #define VAR1 [rsp]
+    sub rsp, 8
+
+    // rax = mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0)
+    xor edi, edi
+    mov rsi, OFFSET SHELLCODE_len
+    mov edx, PROT_READ | PROT_WRITE
+    mov ecx, MAP_PRIVATE | MAP_ANONYMOUS
+    mov r8, -1
+    xor r9d, r9d
+    call QWORD PTR [mmap@GOTPCREL + rip]
+    mov VAR1, rax
+
+    cmp rax, MAP_FAILED
+    je .abort
+
+    // rax = mmove(VAR1, SHELLCODE, SHELLCODE_len)
+    mov rdi, rax
+    lea rsi, [rip+SHELLCODE]
+    mov rdx, OFFSET SHELLCODE_len
+    call QWORD PTR [memmove@GOTPCREL + rip]
+
+    // rax = mprotect(exec_mem, content.len(), PROT_READ | PROT_EXEC)
+    mov rdi, rax
+    mov rsi, OFFSET SHELLCODE_len
+    mov edx, PROT_READ | PROT_EXEC
+    call QWORD PTR [mprotect@GOTPCREL + rip]
+
+    test rax, rax
+    jnz .abort
+
+    mov rax, VAR1
+    call qword ptr VAR1
+
+    // exit(0)
+    xor edi, edi
+    call QWORD PTR [exit@GOTPCREL + rip]
+
+.abort:
+    call QWORD PTR [abort@GOTPCREL + rip]