Add CI and test (#1)

Add CI and test

.github/workflows/ci.yml

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+name: CI
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+
+      - name: Build with CMake
+        run: |
+          mkdir build
+          cd build
+          cmake .. -G "Unix Makefiles"
+          make
+
+      - name: Upload artifacts
+        uses: actions/upload-artifact@master
+        with:
+          name: vuln-artifact
+          path: build/vuln
+          retention-days: 1
+
+  test:
+    runs-on: ubuntu-latest
+
+    needs: build
+
+    env:
+      FNETD_PASSWORD: 1234
+
+    steps:
+      - uses: actions/checkout@v3
+
+      - uses: actions/download-artifact@master
+        name: Download build artifacts
+        with:
+          name: vuln-artifact
+          path: build/
+
+      - name: Install fnetd
+        run: |
+          wget https://cloud.sec.in.tum.de/index.php/s/n5cJnDqnnpSeEpd/download/fnetd.tar.xz -O fnetd.tar.xz
+          tar -xf fnetd.tar.xz
+          mkdir fnetd/build
+          cd fnetd/build
+          cmake .. -G "Unix Makefiles"
+          make
+          cd ../..
+
+      - name: Setup get_flag
+        run: gcc tests/get_flag.c -o get_flag -O3
+
+      - uses: JarvusInnovations/background-action@v1
+        name: Start fnetd
+        with:
+          run: |-
+            chmod +x build/vuln
+            fnetd/build/fnetd -p 1337 -lt 2 -lm 536870912 "strace -f build/vuln" &
+
+          tail: true
+          wait-on: tcp:localhost:1337
+          wait-for: 1m
+
+      - name: Setup python libs
+        run: pip install -r tests/requirements.txt
+
+      - name: Tests
+        run: python -m unittest discover tests/

tests/common.py

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+#! /usr/bin/env python3
+
+from pwn import *
+from enum import IntEnum
+
+
+class Opcode(IntEnum):
+    ADD = 0
+    ADDI = 1
+    SUB = 2
+    COPY = 3
+    LOADI = 4
+
+
+class Register(IntEnum):
+    A = 0
+    B = 1
+    C = 2
+    D = 3
+    E = 4
+    F = 5
+    G = 6
+    H = 7
+
+
+INSTR_LEN = 8
+
+
+def instr_i(opcode: Opcode, reg1: Register, imm: int):
+    assert (opcode == Opcode.ADDI or opcode == Opcode.LOADI)
+    assert (imm < 2 ** 32)
+    return bytes([opcode, reg1, 0, 0]) + imm.to_bytes(4, byteorder='little')
+
+
+def instr_r(opcode, reg1, reg2):
+    assert (opcode == Opcode.ADD or opcode == Opcode.SUB or opcode == Opcode.COPY)
+    return bytes([opcode, reg1, 0, 0, reg2, 0, 0, 0])
+
+
+def exec_program(program: bytes) -> int | None:
+    context.log_level = 'debug'
+    with remote("localhost", 1337, fam="ipv4") as p:
+        p.recvuntil(b"Password: ", timeout=1)
+        p.sendline(b"1234")
+
+        msg = p.recvuntil(b"always a Surprise)", timeout=1)
+        if msg == b'':
+            return None
+        print(msg.decode())
+
+        msg = p.recvuntil(b"should it bee?", timeout=1)
+        if msg == b'':
+            return None
+        print(msg.decode())
+
+        len_msg = str(len(program) // INSTR_LEN).encode()
+        log.info(f"Sending: {len_msg}")
+        p.sendline(len_msg)
+
+        msg = p.recvuntil(b"Now your program:", timeout=1)
+        if msg == b'':
+            return None
+        print(msg.decode())
+
+        log.info(f"Sending program: {list(program)}")
+        p.send(program)
+
+        msg = p.recvuntil(b"Your program exited with ", timeout=1)
+        if msg == b'':
+            return None
+        print(msg.decode())
+
+        exit_code = int(p.recvuntil(b"!", drop=True, timeout=1))
+        return exit_code

tests/get_flag.c

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+#include <stdio.h>
+
+int main(void) {
+    printf("flag_0123456789abcdef0123456789abcdef\n");
+    return 0;
+}

tests/requirements.txt

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+# requirements.txt
+
+pwntools>=4.11.1

tests/test_add.py

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+import unittest
+from common import *
+
+
+class BasicInstructionTest(unittest.TestCase):
+    def test_addi(self):
+        for val in [0, 1, 50, 256, 0x543210, 0xFFFFFFFF]:
+            program = instr_i(Opcode.ADDI, Register.A, val)
+            exit_code = exec_program(program)
+            self.assertIsNotNone(exit_code, "Connection timeout!")
+            self.assertEqual(exit_code, val & 0xFF, "Computed the wrong result!")
+
+
+if __name__ == '__main__':
+    unittest.main()