add debian lts security advisories

ircbot/plugin/debian_lts_security.py

@@ -0,0 +1,82 @@
+import operator
+import re
+from collections import namedtuple
+from datetime import datetime
+from typing import List
+from xml.etree import ElementTree
+
+import requests
+
+
+DLA = namedtuple('DLA', ('number', 'package', 'link', 'description', 'date'))
+last_seen = None
+
+
+def dla_list():
+    req = requests.get('https://www.debian.org/lts/security/dla-long')
+    req.raise_for_status()
+
+    root = ElementTree.fromstring(req.content)
+    for item in root.iter('{http://purl.org/rss/1.0/}item'):
+        # title is of the form "DLA-3804 linux - security update"
+        title = item.find('{http://purl.org/rss/1.0/}title')
+        assert title is not None
+        assert title.text is not None
+        # group 1: dla number, group 2: optional package name
+        # line ends with the type of notice, see DSA-4204, DSA-4205 for examples
+        m = re.match(r'DLA-(\d+) ?(.+)? - ', title.text)
+        assert m, title.text
+        dla_num = int(m.group(1))
+        package = m.group(2)
+        link_elt = item.find('{http://purl.org/rss/1.0/}link')
+        assert link_elt is not None
+        link = link_elt.text
+
+        # description has random html tags and whitespace
+        description_elt = item.find('{http://purl.org/rss/1.0/}description')
+        assert description_elt is not None
+        assert description_elt.text is not None
+        description = description_elt.text.strip()
+        description = description.replace('\n', ' ')
+        description = re.sub('<[^<]+>', '', description)  # not secure! but good enough
+        date_elt = item.find('{http://purl.org/dc/elements/1.1/}date')
+        assert date_elt is not None
+        assert date_elt.text is not None
+        date = datetime.strptime(date_elt.text, '%Y-%m-%d')
+
+        yield DLA(
+            number=dla_num,
+            package=package,
+            link=link,
+            description=description,
+            date=date,
+        )
+
+
+def summarize(description, limit=256):
+    words = description.split()
+    line = ''
+    for word in words:
+        new_line = line + ' ' + word
+        if len(new_line) > limit:
+            return line.strip() + ' [...]'
+        else:
+            line = new_line
+    return line.strip()
+
+
+def get_new_dlas():
+    """Return new DLA summary lines."""
+    global last_seen
+    lines: List[str] = []
+    # exceptions (including HTTP error codes) are handled in timer.py
+    dlas = list(dla_list())
+
+    if last_seen is not None:
+        for dla in sorted(dlas, key=operator.attrgetter('number')):
+            if last_seen < dla.number:
+                lines.append('\x02\x0304[DLA {dla.number}] {dla.package} - {dla.link}'.format(dla=dla))
+                lines.append('\x0304' + summarize(dla.description))
+
+    last_seen = max(dla.number for dla in dlas)
+    return lines

ircbot/plugin/timer.py

@@ -4,6 +4,7 @@
 from textwrap import dedent
 from traceback import format_exc
 
+from ircbot.plugin import debian_lts_security
 from ircbot.plugin import debian_security
 
 # Check for Debian security announcements every 5 minutes
@@ -20,9 +21,13 @@ def register(bot):
 
 def timer(bot):
     dsa_freq = DSA_FREQ_DEFAULT
+    dla_freq = DSA_FREQ_DEFAULT
 
     last_date = None
+    last_date_dla = None
+
     last_dsa_check = None
+    last_dla_check = None
 
     while not (hasattr(bot, 'connection') and bot.connection.connected):
         time.sleep(2)
@@ -41,6 +46,7 @@ def timer(bot):
 
                 # After a successful fetch, we reset timer to 5m
                 dsa_freq = DSA_FREQ_DEFAULT
+
         except Exception as ex:
             error_msg = f'ircbot exception in timer: {ex}'
             bot.say('#rebuild', error_msg)
@@ -58,4 +64,34 @@ def timer(bot):
             )
             dsa_freq = min(dsa_freq + DSA_FREQ_BACKOFF, DSA_FREQ_MAX)
 
+        try:
+            last_date_dla, old_dla = date.today(), last_date_dla
+            if old_dla and last_date_dla != old_dla:
+                bot.bump_topic()
+
+            if last_dla_check is None or time.time() - last_dla_check > 60 * dla_freq:
+                last_dla_check = time.time()
+
+                for line in debian_lts_security.get_new_dlas():
+                    bot.say('#rebuild', line)
+
+                dla_freq = DSA_FREQ_DEFAULT
+
+        except Exception as ex:
+            error_msg = f'ircbot exception in timer: {ex}'
+            bot.say('#rebuild', error_msg)
+            bot.handle_error(
+                dedent(
+                    """
+                {error}
+
+                {traceback}
+                """,
+                ).format(
+                    error=error_msg,
+                    traceback=format_exc(),
+                ),
+            )
+            dla_freq = min(dla_freq + DSA_FREQ_BACKOFF, DSA_FREQ_MAX)
+
         time.sleep(1)