More SSH management.

[cas.git] / src / ssh_keys / utils.py

diff --git a/src/ssh_keys/utils.py b/src/ssh_keys/utils.py
new file mode 100644 (file)
index 0000000..e8756a2
--- /dev/null
+++ b/src/ssh_keys/utils.py
@@ -0,0 +1,60 @@
+from datetime import datetime, timedelta
+import re
+import subprocess
+
+
+def get_key_details(key):
+    """
+    >>> get_key_details('ssh-dss 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 epsilon')
+    {'algo': 'DSA', 'bits': 1024, 'md5': 'f6:78:a7:9e:6b:41:dc:31:f4:39:12:5f:2b:0c:7a:11', 'comment': 'epsilon'}
+    """
+    process = subprocess.run(
+        ['ssh-keygen', '-lEmd5', '-f-'],
+        input=key.encode('utf-8'),
+        stdout=subprocess.PIPE,
+        stderr=subprocess.PIPE)
+    if process.returncode != 0:
+        raise ValueError(process.stderr.decode('utf-8'))
+
+    output = process.stdout.decode('utf-8').rstrip()
+    m = re.match(
+        r'^(?P<bits>\d+) MD5:(?P<md5>[a-f0-9:]+) (?P<comment>.*) \((?P<algo>.*)\)$',
+        output
+    )
+    return {
+        'algo':  m.group('algo'),
+        'bits': int(m.group('bits')),
+        'md5': m.group('md5'),
+        'comment': m.group('comment'),
+    }
+
+
+def parse_log_line(line, year=None, allow_future_days=7):
+    """
+    >>> sorted(parse_log_line(
+    ...     'Jan  1 2:34:56 heta sshd[4112]: Accepted publickey for localuser from 0.0.0.0 port 33980 ssh2: RSA f6:78:a7:9e:6b:41:dc:31:f4:39:12:5f:2b:0c:7a:11',
+    ...     year=2019).items())
+    [('algo', 'RSA'), ('datetime', datetime.datetime(2019, 1, 1, 2, 34, 56)), ('host', 'heta'), ('ip', '0.0.0.0'), ('md5', 'f6:78:a7:9e:6b:41:dc:31:f4:39:12:5f:2b:0c:7a:11'), ('user', 'localuser')]
+    """
+    logline_re = r'^(?P<time>\w{3}\s+\d+\s+\d?\d:\d\d:\d\d) (?P<host>\S+) .*: Accepted publickey for (?P<user>\S*) from (?P<ip>[\S]+) port .* ssh2: (?P<algo>\w+) (?P<md5>[a-f0-9:]+)$'
+
+    m = re.match(logline_re, line)
+    if m is None:
+        return None
+    dt = datetime.strptime(m['time'], '%b %d %H:%M:%S')
+    if year is not None:
+        dt = dt.replace(year=year)
+    else:
+        now = datetime.now()
+        dt = dt.replace(year=now.year)
+        if (dt - now).days > allow_future_days:
+            dt = dt.replace(year=dt.year - 1)
+
+    return {
+        'datetime': dt,
+        'host': m['host'],
+        'user': m['user'],
+        'ip': m['ip'],
+        'algo': m['algo'],
+        'md5': m['md5'],
+    }