Detect OpenSSH private keys

pre_commit_hooks/detect_private_key.py

@@ -0,0 +1,33 @@
+from __future__ import print_function
+
+import io
+import sys
+
+import argparse
+
+
+def detect_private_key(argv=None):
+    parser = argparse.ArgumentParser()
+    parser.add_argument('filenames', nargs='*', help='Filenames to check')
+    args = parser.parse_args(argv)
+
+    private_key_files = []
+
+    for filename in args.filenames:
+        with io.open(filename, 'r') as f:
+            content = f.read()
+            if 'BEGIN RSA PRIVATE KEY' in content:
+                private_key_files.append(content)
+            if 'BEGIN DSA PRIVATE KEY' in content:
+                private_key_files.append(content)
+
+    if private_key_files:
+        for private_key_file in private_key_files:
+            print('Private key found: {0}'.format(private_key_file))
+        return 1
+    else:
+        return 0
+
+
+if __name__ == '__main__':
+    sys.exit(detect_private_key())