Merge pull request #2154 from GNS3/fix/2069

Use a stock BusyBox for the Docker integration

README.rst

@@ -29,6 +29,11 @@ In addition of Python dependencies listed in a section below, other software may
 * mtools is recommended to support data transfer to/from QEMU VMs using virtual disks.
 * i386-libraries of libc and libcrypto are optional (Linux only), they are only needed to run IOU based nodes.
 
+Docker support
+**************
+
+Docker support needs the script program (`bsdutils` or `util-linux` package), when running a docker VM and a static busybox during installation (python3 setup.py install / pip3 install / package creation).
+
 Branches
 --------
 

gns3server/compute/docker/docker_vm.py

@@ -520,10 +520,14 @@ class DockerVM(BaseNode):
         # https://github.com/GNS3/gns3-gui/issues/1039
         try:
             process = await asyncio.subprocess.create_subprocess_exec(
-                "docker", "exec", "-i", self._cid, "/gns3/bin/busybox", "script", "-qfc", "while true; do TERM=vt100 /gns3/bin/busybox sh; done", "/dev/null",
+                "script",
+                "-qfc",
+                f"docker exec -i -t {self._cid} /gns3/bin/busybox sh -c 'while true; do TERM=vt100 /gns3/bin/busybox sh; done'",
+                "/dev/null",
                 stdout=asyncio.subprocess.PIPE,
                 stderr=asyncio.subprocess.STDOUT,
-                stdin=asyncio.subprocess.PIPE)
+                stdin=asyncio.subprocess.PIPE
+            )
         except OSError as e:
             raise DockerError("Could not start auxiliary console process: {}".format(e))
         server = AsyncioTelnetServer(reader=process.stdout, writer=process.stdin, binary=True, echo=True)

gns3server/compute/docker/resources/bin/udhcpc

@@ -0,0 +1,15 @@
+#!/gns3/bin/busybox sh
+
+SCRIPT="/gns3/etc/udhcpc/default.script"
+
+if [ "$(cat "/proc/$PPID/comm" 2>/dev/null)" = ifup ]; then
+	# remove "-n" argument
+	for arg do
+		shift
+		[ "$arg" = "-n" ] || set -- "$@" "$arg"
+	done
+	# add default parameters
+	set -- -t 3 -T 2 -A 1 -b "$@"
+fi
+
+exec /tmp/gns3/bin/udhcpc -s "$SCRIPT" "$@"

setup.py

@@ -16,6 +16,10 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import sys
+import os
+import shutil
+import subprocess
+
 from setuptools import setup, find_packages
 from setuptools.command.test import test as TestCommand
 
@@ -39,6 +43,28 @@ class PyTest(TestCommand):
         sys.exit(errcode)
 
 
+BUSYBOX_PATH = "gns3server/compute/docker/resources/bin/busybox"
+
+
+def copy_busybox():
+    if not sys.platform.startswith("linux"):
+        return
+    if os.path.isfile(BUSYBOX_PATH):
+        return
+    for bb_cmd in ("busybox-static", "busybox.static", "busybox"):
+        bb_path = shutil.which(bb_cmd)
+        if bb_path:
+            if subprocess.call(["ldd", bb_path],
+                               stdin=subprocess.DEVNULL,
+                               stdout=subprocess.DEVNULL,
+                               stderr=subprocess.DEVNULL):
+                shutil.copy2(bb_path, BUSYBOX_PATH, follow_symlinks=True)
+                break
+    else:
+        raise SystemExit("No static busybox found")
+
+
+copy_busybox()
 dependencies = open("requirements.txt", "r").read().splitlines()
 
 setup(

tests/compute/docker/test_docker_vm.py

@@ -1343,7 +1343,15 @@ async def test_start_aux(vm):
 
     with asyncio_patch("asyncio.subprocess.create_subprocess_exec", return_value=MagicMock()) as mock_exec:
         await vm._start_aux()
-    mock_exec.assert_called_with('docker', 'exec', '-i', 'e90e34656842', '/gns3/bin/busybox', 'script', '-qfc', 'while true; do TERM=vt100 /gns3/bin/busybox sh; done', '/dev/null', stderr=asyncio.subprocess.STDOUT, stdin=asyncio.subprocess.PIPE, stdout=asyncio.subprocess.PIPE)
+        mock_exec.assert_called_with(
+            "script",
+            "-qfc",
+            "docker exec -i -t e90e34656842 /gns3/bin/busybox sh -c 'while true; do TERM=vt100 /gns3/bin/busybox sh; done'",
+            "/dev/null",
+            stderr=asyncio.subprocess.STDOUT,
+            stdin=asyncio.subprocess.PIPE,
+            stdout=asyncio.subprocess.PIPE
+        )
 
 
 async def test_create_network_interfaces(vm):