#!/usr/bin/python2.2
from slides import Slide, Bullet, SubBullet, URL
from twslides import Lecture
lecture = Lecture(
"Twisted.Conch: SSH in Python",
Slide("Introduction",
),
Slide("Other implementations (servers)",
Bullet("OpenSSH",
SubBullet(URL("http://www.openssh.org")),
),
Bullet("FSecure SSH",
SubBullet(URL("http://www.f-secure.com/products/ssh/")),
),
Bullet("LSH",
SubBullet(URL("http://www.lysator.liu.se/~nisse/lsh/")),
),
),
Slide("Other implementations (clients)",
Bullet("PuTTY",
SubBullet(URL("http://www.chiark.greenend.org.uk/~sgtatham/putty/")),
),
Bullet("TeraTerm",
SubBullet(URL("http://www.ayera.com/teraterm/")),
),
Bullet("MindTerm",
SubBullet(URL("http://www.appgate.com/mindterm/")),
),
),
Slide("Why Twisted?",
Bullet("Asynchronous"),
Bullet("Python"),
Bullet("High-Level"),
),
Slide("No Forking or Threads",
Bullet("Forking is expensive"),
Bullet("Threads are complicated/expensive, esp. in Python"),
Bullet("Asynch means no worrying about any of that"),
Bullet("Makes running a session 2x as fast in Conch as in OpenSSH"),
),
Slide("Security - No Pointers",
SubBullet("No buffer overflows"),
SubBullet("No off-by-1 errors"),
SubBullet("No malloc/free bugs"),
SubBullet("No arbitrary code execution"),
),
Slide("Security - High Level",
Bullet("Strong built-in library"),
Bullet("Exceptions"),
),
Slide("Security - Not Root",
Bullet("Limits vulnerablity in a compromise"),
Bullet("Allows use of process limits/etc."),
),
Slide("Interfacing with other software",
Bullet("OpenSSH interacts only through separate processes",
SubBullet("Expensive"),
SubBullet("Complicated"),
),
Bullet("Conch can interact in-process",
SubBullet("Faster"),
SubBullet("Easy integration to other Twisted and Python libraries"),
),
),
Slide("Speed",
Bullet("C is faster than Python"),
Bullet("Interpreter cost is high for the client"),
Bullet("FSH-style connection caching helps a bit"),
Bullet("Psyco helps as well"),
),
Slide("Age",
Bullet("Conch is new",
SubBullet("First commit was July 15, 2002"),
),
Bullet("Hasn't had a security aduit"),
Bullet("Shouldn't be used in security-critical systems"),
),
Slide("Applications with Conch",
Bullet("Reality: MUD framework"),
Bullet("Insults: async. replacement for curses in Conch apps"),
),
Slide("Future Directions",
Bullet("Generic authentication forwarding"),
Bullet("Work on applications"),
Bullet("Auditing of the code"),
Bullet("Increase speed"),
Bullet("SFTP/SCP"),
Bullet("Key Agent"),
Bullet("DNSSEC"),
),
Slide("Conclusion",
Bullet("Working implementation in Python"),
Bullet("Much room for improvement"),
),
)
lecture.renderHTML(".", "conch-%d.html", css="main.css")