344: 1337: Part 4

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1337: Part 4
Mrs. Roberts would have gotten up sooner, of course, but she was busy piping find ~ and find ~nomad into xargs shred, just in case.
Title text: Mrs. Roberts would have gotten up sooner, of course, but she was busy piping find ~ and find ~nomad into xargs shred, just in case.

[edit] Explanation

This is the fourth part of five in the "1337" series. The title 1337 is "L-eet", or "elite", using the Leet alphabet.

All comics in the series:

This series was released on 5 consecutive days (Monday-Friday) and not over the usual Monday/Wednesday/Friday schedule. The comic is narrated by Cueball as seen in part 2 comic, but that Cueball is not shown here, but still he is part of this comic series, and thus also this comic.

In this part Elaine Roberts returns to the second best hacker in the world, (she being the best according to part 2), her mom Mrs. Roberts. Together they are an unstoppable force and they help out a guy called Jon with a CSS decryptor.

This implies that Jon Lech Johansen's DeCSS was written by Elaine. Jon Lech Johansen, also known as DVD Jon, is famous for DeCSS, a DVD decryption program that removes the copy protection from commercial DVDs. The Motion Picture Association of America, also known as the MPAA, were not amused.

Both the MPAA and the Recording Industry Association of America (RIAA) use the Digital Millenium Copyright Act, shortened to DMCA, as a kind of brute club to silence "infringements" on their copyright. In a perfect world, the DMCA provides safe harbor protection to websites and consumers to make fair use of copyrighted content while also affording copyright owners the ability to protect their works from being pirated. In this world, this means that any content protection system, no matter how weak and poorly executed, cannot be circumvented and discussion of circumvention is illegal as well.

This is not a perfect world and in the end the Roberts team is noticed and two men with black bowler hats and briefcases with the abbreviations MPAA and RIAA shows up at their house to arrest them. The two men look very much like Thomson and Thompson from The Adventures of Tintin.

When Elaine is not ready to let them arrest her, and draws her knife, they instead draw their katana swords, out of their (way too short) briefcases. Mrs. Roberts says to her daughter that she should calm down because it is illegal to slice people up in their own houses.

However the two men disagree and refer to the DCMA Title IV, Section 408: Authorization of Deadly Force. So now the two women are in lethal danger.

But of course, Richard Stallman, founder of the GNU Project and stalwart defender of freedom and copyleft, cannot stand for this kind of repression of freedom. (In the real world, Stallman is not a swordsman, but he is always depicted with two katana swords in xkcd, first time was in 225: Open Source; there is also no Title IV, Section 408 of the DMCA; Title IV ends with Section 407.) In keeping with the "Kill Bill" themes from earlier in the series, Randall imagines the conflict between Elaine/Stallman/Mrs. Roberts vs MPAA/RIAA agents as an action-packed katana battle rather than the legal battle it would likely have been in real life.

The title text is talking about a Linux-ism. In Linux (and all Unix derivatives) ~ is a symbol for a user's home directory (usually /home/<username>). Presumably "nomad" is Elaine's username. find is an application that recursively walks a filesystem, listing all files, and xargs shred takes those files and securely erases each one with pseudo-random data. This is different from simply deleting a file, which merely removes the pointer in the filesystem's record tables to the file's location on the hard disk. The latter can usually be recovered from, secure delete however requires physically taking apart a disk and reading individual bits for remaining magnetic charge to attempt to reconstruct what was there.

Proprietary hardware is hardware (the electronics part rather than the software) created and uses only by that company as opposed to open hardware that uses parts or chips common to everyone. Proprietary hardware used to found in most gaming consoles and apple/mac devices but that isn't as common now since the cost of designing your own hardware is too expensive compared to using common chips.

[edit] Transcript

[Elaine is sitting under tree on a grassy meadow typing on her laptop. Two trees are in the background where rolling hills goes to the horizon with a single cloud over the trees. Above the frame is text narrated by the Cueball from the first panel in the 2nd comic in the series:]
Cueball (narrating): As time passed, Elaine intensified her hacking work, anonymously publishing exploit after exploit.
[Elaine, wearing a backpack, is walking up to a door where her mom Mrs. Roberts is greeting her in the open door at the top of two steps. Above this very low panels frame there is more of Cueballs narration:]
Cueball (narrating): To crack open proprietary hardware, she teamed up with one of the top experts in signal processing and data transferring protocols.
Elaine: Hi, mom.
Mrs. Roberts: Hello, dear. Did you have fun?
[Elaine is lying on the floor with her laptop in front of her facing left with charger no the floor further left. Mrs. Roberts is sitting to the right facing right on a chair working on her computer at a table. Cueball is still narrating above the frame:]
Cueball (narrating): They were an unstoppable team.
Elaine: I finished the CSS decryptor.
Mrs. Roberts: Good, dear. I'll send it along to Jon.
[Pan to the right where two men in black bowler hats arrive. Both holds briefcases the first guys reads RIAA and the other guy reads MPAA. Cueball's last narration in the comic is above the frame:]
Cueball (narrating): And were eventually noticed.
RIAA man: Game's over.
MPAA man: You're coming with us.
Briefcase 1: RIAA
Briefcase 2: MPAA
[Pan back left to the women. Mrs. Roberts stays in her chair sitting at her computer still typing, the screen emitting light, but Elaine has moved around to the right of the table and pulls out her folding knife and swings it open.]
Elaine: Oh, are we?
Mrs. Roberts: Now now, Elaine-
Knife: Shink
[Pan back right to the two men who simultaneously pull a katana sword out of each of their briefcase, while still holding on the the handle with the other hand. When when opened like this it causes two pieces of paper to fly out of the RIAA man and a note book to fly out of the MPAA mans briefcase.]
Katan sword1 1: Shing
Katan sword1 2: Shing
[Pan back to the women. Mrs. Roberts continues to type on the laptop, a line goes up from the keyboard indicating activity. Elaine still holds her open folding knife out, so the tip now touches the right frame of the panel.]
Mrs. Roberts: Don't let them provoke you, dear.
Man (off-panel): We don't want to hurt you, Ma'am.
Mrs. Roberts: Don't by silly. Record company employees can't just go into houses and slice people up.
[Pan back right to the two men who holds up the katana sword having left their briefcase closed on the floor. The closest RIAA man is holding a hand up, the other MPAA man is holding his sword in two hands and pointing it threateningly forward.]
RIAA Man: Ah, so you haven't read the DMCA.
MPAA Man: Title IV, Section 408: Authorization of Deadly Force.
[A wide panel showing the whole scene with even Mrs. Robert now standing having just pushed her chair back, the computer inert. Elaine is bending in the knees knife at the ready. Both bowler hat men, stil holding their swords as before, but no hands up, have turned to loo right back over their shoulder to see who speaks, as a voice comes from off-panel right.]
Richard Stallman (off-panel): Hark!


[The scene pans further right, so the two women is no longer in the panel, but Richard Stallman can now be seen with his wild beard and long hair and holding two katana swords one in front of him and one over his head also pointing towards the two bowler hat med. They are standing normally, looking back at Stallman the MPAA man nearest him holds a hand to his mouth as he speaks.]
Richard Stallman: Cease this affront to freedom
Richard Stallman: Or stand and defend yourselves!
MPAA Man: Stallman!


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Discussion

It's the piping of "find ~" (all files in Mom's current login's home directory) and "find ~nomad" (all files in the home directory of user "nomad", presumably that's Elaine's account also on Mom's machine, having recently been on a 'life journey' of self-discovery and learning) through the shred command that is doing the directory recursion, as part of the "find" command's default behaviour (IIRC). I've never used the shredding command myself, but I'd say that it's operating on the list given it by the "find", rather than doing the directory-burrowing itself, for which I'd expect parameters of a "~/* ~/.* -r" (or "-R" or "-s") type of variant to activate the "all files, in all directories from here" inspection... ICBW. Best to check the man pages, though... (Also Mom's obviously got maximum rights for herself, or is drilling through su, as I'd expect.) 178.98.31.27 08:30, 19 June 2013 (UTC)

"find" is passed a variety of arguments - an argument that is not part of an optional parameter (i.e. -name \*.php would specify all files ending with ".php" - the backslash is used to prevent bash or another shell from expanding the parameter into a full list of .php files) is treated as a file or directory to begin searching. So "find ~" would begin searching in the user's own home directory; "find ~nomad" would begin the search in the home directory of the user "nomad". All file and directory names are sent to stdout (standard output).
Piping the result requires the use of the | symbol (shift-backslash). It's used to pipe data from stdout to stdin (standard input).
"xargs" is a Linux command that constructs command lines by reading a list of files from stdin and treating each with a command (and optional arguments) specified after "xargs".
"shred" is a program that takes a filename as a parameter and overwrites the file repeatedly to keep the original contents, which can be discerned using increasingly-expensive hardware solutions, from being pieced together.
With this in mind:
find ~ | xargs shred
1) finds all files (and directories) in the hierarchy of the user's home directory, and sends the list to stdout;
2) the list gets piped to "xargs", which
3) passes each file to "shred" for shredding.
Issues regarding symbolic links, filtering directory names from the operation, and modifying the operating parameters of "shred" will be left to the aspiring sysadmin to discover for theirself. Thokling (talk) 13:42, 21 September 2013 (UTC)


It should be noted that if you want to have a file system that can shred data reliably you will need to use a file system without journaling or it is possible some of your data can be stored in the journal(The journal describes the nature of a write and its prior state before writing to it in order to safeguard the file system against unexpected shutdown).

What is more a lot of modern hard drive detect bad sectors and move data elsewhere, leaving the old data in a sector marked as "do not use". This data will not be securely deleted from these sectors and can be manually accessed by forensics later.

The commonly accepted solution is to use block device level encryption to prevent sensitive data from ever being written.

In short the shred command can give someone an unrealistic sense of security. I don't think this is relevant to the comic but I just wanted to share what I knew on the subject. 108.162.246.117 08:52, 1 November 2013 (UTC)

"Title IV, Section 408: Authorization of deadly force." Does that make any sense in the real world? I don't see an explanation about this remark. Daniel Carrero (talk) 09:48, 10 April 2014 (UTC)

Someone should put in that Stallman was given a Katana.108.162.249.210 00:29, 13 June 2014 (UTC)

And also that katana-wielding Stallman comes from 225: Open Source. 108.162.229.173 22:29, 6 April 2015 (UTC)

find can take multiple path arguments so she could just used find ~ ~nomad. 108.162.238.181 02:19, 14 September 2015 (UTC)

Were people still using the Creative Nomad range of MP3 players at this point? Because the linux driver for the Nomad ran under a user account named "nomad", and the fact that it's the RIAA coming after them implies that MP3s are what they're interested in. 162.158.255.69 05:32, 16 September 2015 (UTC)

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