New GPG key

I’ve uploaded a new GPG key to various keyservers, fetch it manually or on the command line:

$ gpg --recv-keys 0xF75964F29DC6C210

Before creating the key, I took inspiration from Ubuntu and Christopher Wellons, arriving at this for my gpg.conf:

cert-digest-algo SHA512
default-preference-list SHA512 SHA384 SHA256 SHA224 AES256 AES192 AES CAST5 BZIP2 ZLIB ZIP Uncompressed
personal-cipher-preferences AES256 AES192 AES
personal-digest-preferences SHA512 SHA384 SHA256 SHA224
s2k-cipher-algo AES256
s2k-digest-algo SHA512
s2k-mode 3
s2k-count 65011712

The first half is in order to use the SHA-2 and AES instead of SHA-1 and CAST5, while the s2k settings are there to make brute force as expensive as possible in the event that my private key should be compromised.

I’m starting from scratch with my web of trust, so if you want to play key signing, let me know.

Chinese Diceware

I’ve been trying to come up with strong passwords since forever, and have failed to find a magic alternative to entropy. Recently, I took Diceware for a roll, but wasn’t entirely happy with passwords like “wn rare swung strop situs slept”—wn isn’t even a word, is it? I also tried the Swedish dictionary but wasn’t much happier.

How about Mandarin Chinese, written using pinyin? There are only around 400 pinyin syllables, but thousands of characters with different meanings, so I guessed that for a random sequence of syllables it should often be possible to come up with a somewhat meaningful phrase.

The kHanyuPinlu property from the Unihan database turned out to be an excellent source for character to syllable mapping, so I wrote to reverse that mapping. The output is a list of 392 pinyin syllables with example characters in traditional and simplified Chinese.

Unfortunately, 392 is not a power of 6, so using real dice to generate the numbers is a bit complicated, albeit possible. Instead I wrote, which uses as few bytes as possible from /dev/random to roll a die with an arbitrary number of sides.

Using my list and my virtual D-392, here are the first 6-syllable pinyin phrases I generated, each with a memorable (?) Chinese phrase and a rough English translation.

  • yan kai bo ren se dai—眼開撥任色帶—eyes open, poke any ribbon
  • zui ku ba ge mei xu—最酷八個沒序—the coolest eight have no order
  • ban zhai dian die keng bao—搬宅殿爹吭抱—moving villa/palace, dad says hold (this)
  • you mu sa kang xu su—有母萨扛需速—(things) carried by mother Bodhisattva need speed

A native speaker would probably be able to come up with better phrases, but I think that I could remember any of these, with 最酷八個沒序 being the easiest. If this is a representative sample, I think the scheme works.

How about the entropy? With 392 syllables, each syllable contributes log2(392) = 8.6 bits, so these 6-syllable phrases have 51.6 bits of entropy, slightly better than a completely random 8-character alphanumeric password. English Diceware has 12.9 bits of entropy per word, so to get as much entropy as with a 6-word English phrase, a 9-syllable Chinese phrase is needed. The average word and syllable length are 4.2 and 3.2 respectively, so the average phrase lengths (including spaces) would be 30.2 for English and 36.8 for Chinese. (Removing spaces blindly will lose some entropy if the pinyin becomes ambiguous.)

Feel free to use/improve my lists and scripts, and never forget: the coolest eight have no order!


Mormor dog ikväll…

Jag älskade verkligen att vara i Kålaboda när jag var liten. Sommaren 1986 kunde jag inte prata än, men jag följde gärna med mormor och morfar i lagården, som så många gånger senare under min uppväxt. Den sommaren filmade pappa, och lyckades få med mormor i några korta sekvenser. De här stillbilderna är från del 1 och 5 av Sommar i Kålaboda:

Britta & Folke i lagården

Britta & Folke i lagården

Lunch på gården

Lunch på gården

Sista gången som jag träffade mormor var i september, det känns inte så länge sen. Nu kommer jag aldrig att få träffa henne igen, kvar finns bara bilder, filmer och minnen. Lagården finns inte heller kvar, men jag minns tydligt hur gott det luktade i rummet med allt tunnbröd, tunnbröd som mormor hade bakat. Det är bara ett av många mormorsminnen.

Jag kommer att sakna dig, mormor…

Britta & Edison

Britta & Edison