[python] Fix {{ ldd }} and add tests

Signed-off-by: Wojtek Porczyk <woju@invisiblethingslab.com>

.ci/lib/stage-clean-check.jenkinsfile

@@ -57,6 +57,7 @@ stage('clean-check') {
         # python/ subdir does not have makefiles, so no clean
         rm -rf /tmp/*.clean-check.clean/python/graminelibos/__pycache__
         rm -rf python/graminelibos/__pycache__
+        rm -rf tests/__pycache__
 
         ./scripts/clean-check
     '''

.ci/lib/stage-test.jenkinsfile

@@ -53,4 +53,15 @@ stage('test') {
             }
         }
     }
+
+    timeout(time: 15, unit: 'MINUTES') {
+        try {
+            sh '''
+                python3 -m pytest -v --junit-xml tests.xml tests/
+            '''
+        } finally {
+            junit 'tests.xml'
+            sh 'rm -rf tests.xml'
+        }
+    }
 }

python/graminelibos/gen_jinja_env.py

@@ -8,11 +8,7 @@
 
 from . import _CONFIG_PKGLIBDIR
 
-def ldd(*args):
-    '''
-    Args:
-        binaries for which to generate manifest trusted files list.
-    '''
+def parse_ldd(output):
     # Be careful: We have to skip vdso, which doesn't have a corresponding file on the disk (we
     # assume that such files have paths starting with '/', seems ldd always prints absolute paths).
     # Also, old ldd (from Ubuntu 16.04) prints vdso differently than newer ones:
@@ -21,14 +17,25 @@ def ldd(*args):
     # new:
     #     linux-vdso.so.1 (0x00007ffd31fee000)
     ret = set()
-    for line in subprocess.check_output(['ldd', *(os.fspath(i) for i in args)]).decode('ascii'):
+    for line in output.rstrip('\n').split('\n'):
         line = line.strip().split()
+        if len(line) == 1 and line[0].endswith(':'):
+            # header for when there are multiple binaries given
+            continue
         if line[1] == '=>' and line[2].startswith('/'):
             ret.add(line[2])
         elif line[0].startswith('/') and line[1].startswith('/'):
             ret.add(line[0])
     return sorted(ret)
 
+def ldd(*args):
+    '''
+    Args:
+        binaries for which to generate manifest trusted files list.
+    '''
+    return parse_ldd(
+        subprocess.check_output(['ldd', *(os.fspath(i) for i in args)]).decode('ascii'))
+
 def python_get_sys_path(interpreter, include_nonexisting=False):
     for path in subprocess.check_output([interpreter, '-c',
         '''import sys; print('\\0'.join(path for path in sys.path if path), end='')'''

tests/test_ldd.py

@@ -0,0 +1,26 @@
+from graminelibos.gen_jinja_env import parse_ldd
+
+def test_parse_ldd():
+    output = parse_ldd(
+        # collected with glibc 2.31-0ubuntu9.9 on a helloworld app
+        '''\
+\tlinux-vdso.so.1 (0x00007ffd56342000)
+\tlibc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f3a87190000)
+\t/lib64/ld-linux-x86-64.so.2 (0x00007f3a8738c000)
+''')
+    assert output == ['/lib/x86_64-linux-gnu/libc.so.6']
+
+def test_parse_ldd_multiple_binaries():
+    output = parse_ldd(
+        # collected with glibc 2.36-9+deb12u3
+        '''\
+/usr/bin/cat:
+\tlinux-vdso.so.1 (0x00007ffe71bfe000)
+\tlibc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fa5165ff000)
+\t/lib64/ld-linux-x86-64.so.2 (0x00007fa5167f8000)
+/usr/bin/echo:
+\tlinux-vdso.so.1 (0x00007fff8fde5000)
+\tlibc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f7533ee1000)
+\t/lib64/ld-linux-x86-64.so.2 (0x00007f75340da000)
+''')
+    assert output == ['/lib/x86_64-linux-gnu/libc.so.6']