Stage 2

OK following the link from stage 1 brought me to http://turing.metro.co.uk/ where I downloaded an RSA private key:

Now the hard work begins I suspect…

[An hour or so later…] Well I don’t know much about RSA in detail, other than the “in principle” concepts of public/private key encryption, etc, and having created and used keys for SSL use, but a bit of googling and a read of the OpenSSL man pages seems to have got me somewhere:

I ran this command on the above private key to get at the different “components” of the key: openssl rsa -in comp1.key -noout -text

This gives a long output in hex:

Private-Key: (1022 bit)
modulus:
    37:c0:04:af:3e:8e:80:cb:75:b1:53:0c:9f:b2:dc:
    f4:d3:ce:4a:82:8b:52:f6:a8:48:e0:c5:d8:35:8b:
    26:6c:84:94:de:29:47:24:49:85:72:28:17:8e:06:
    d0:77:17:0c:2a:5d:56:ba:88:d1:07:25:e2:c5:7b:
    01:44:ea:e9:44:38:87:1a:b5:5a:75:d5:98:34:89:
    b3:1f:9e:a4:e2:bd:b7:7a:b7:cf:f3:dc:ac:ea:ac:
    59:2c:83:dc:50:8a:27:0c:69:cb:66:4e:a1:64:9b:
    ca:e8:e4:e0:dc:d8:d4:d0:cc:c8:c4:c0:bc:b8:b4:
    b0:ac:94:13:82:39:51:f1
publicExponent: 65537 (0x10001)
privateExponent:
    13:5b:5d:85:07:60:6d:41:b7:9c:99:2c:61:ea:b5:
    a3:60:43:59:45:98:60:76:fa:19:4b:ca:05:f7:19:
    58:7f:07:4d:b5:11:79:fd:14:75:fc:1c:05:89:af:
    be:04:0b:81:92:d8:13:bb:f2:b3:39:1b:23:70:d3:
    f3:ad:dd:2e:4c:26:d3:1b:a8:56:f1:83:ca:d9:13:
    95:38:e7:80:30:77:a4:f0:d9:77:f9:25:b9:c1:d7:
    8f:2a:e5:b0:31:d8:c3:0e:3a:b1:5c:39:ec:f9:90:
    b5:77:60:a9:cf:95:7e:c7:ed:b3:9c:e6:0b:d1:bb:
    04:29:e8:b4:b1:69:7b:2d
prime1:
    37:c0:04:af:3e:8e:80:cb:75:b1:53:0c:9f:b2:dc:
    f4:d3:ce:4a:82:8b:52:f6:a8:48:e0:c5:d8:35:8b:
    26:6c:84:94:de:29:47:24:49:85:72:28:17:8e:06:
    d0:77:17:0c:2a:5d:56:ba:88:d1:07:25:e2:c5:7b:
    01:44:ea:e8:55:4a:2a:2b:e4:71:8f:02:b1:61:b0:
    e4:34:bf:da:1b:d4:d0:95:ec:ff:0c:f7:da:8d:e1:
    7a:65:99:7f:f1:b3:4e:47:81:00:95:87:d6:8c:5a:
    d8:a8:a4:a0:9c:98:94:90:8c:88:84:80:7c:78:74:
    70:6c:53:d2:41:f9:3b:e4
prime2:
    77:77:2e:77:68:74:73:69:73:69:6c:67:75:6f:65:
    63:74:73:72:65:68:73:72:69:2e:65:6f:63:75:2e:
    2f:6b:6c:62:74:65:68:63:65:6c:20:79:20:20:20:
    20:20:20:20:20:20:20:20:20:20:20:20:20:20:20:
    20:20:0b:8f
exponent1:
    13:a5:24:9d:fc:2e:52:20:40:1b:50:f9:3e:65:80:
    1d:b7:b3:98:57:36:b2:ed:58:80:89:ab:a4:86:4b:
    7e:fe:c2:46:fa:6f:06:98:79:c0:2b:22:df:f6:88:
    71:df:f6:88:71:df:f6:88:71:df:f6:88:71:df:f6:
    b2:8a:b2:4f
exponent2:
    08:79:f2:58:12:97:40:a1:18:c9:40:21:cf:19:4a:
    4e:56:32:e2:c9:03:32:3d:c9:ec:ba:d1:be:72:d0:
    06:19:4f:25:65:30:d4:c9:48:a6:f5:5e:e2:c2:a4:
    c4:e2:c2:a4:c4:e2:c2:a4:c4:e2:c2:a4:c4:e2:c2:
    a4:c4:e1:4d
coefficient:
    14:89:f3:4e:c0:0e:91:ab:96:dd:ca:dd:d5:77:f1:
    32:1c:62:b5:49:1a:a5:d4:2a:97:0b:c5:85:9b:a8:
    b8:d2:32:6d:f1:0e:7d:6e:96:92:3b:60:84:10:f2:
    a9:fe:74:70:41:56:5c:c2:7b:56:4f:26:af:a7:30:
    4e:8b:0f:bd:82:94:55:72:94:09:b9:6b:7a:d2:d3:
    79:4f:79:4e:56:e4:a6:b8:b3:3e:4c:be:fb:96:fb:
    a5:0b:92:8b:79:a9:2c:c8:be:e9:58:2f:72:34:ed:
    85:f5:cf:60:d8:36:26:32:69:82:6b:5e:0b:87:de:
    95:82:ff:d8:54:c0:99:3f

Next I used a convenient online hex-to-ascii converter http://tomeko.net/online_tools/hex_to_ascii.php?lang=en on each of these sections in turn. Most of the sections just returned what appears to be gibberish, so I’m not sure what to do about that (ignore? discard), but the “prime2” section was clearly something more relevant: ww.whtsisilguoectsrehsri.eocu./klbtehcel y [11][143]

Now, ignoring the last couple of characters which fall outside the tomeko.net conversion range and are thus rendered simply as byte values, that string looks a lot like a messed-up URL. The first bit seems to be “www” but the key is actually at the end, though massively helped by knowing the context of the whole puzzle (i.e. GCHQ involvement!) - you can see the word “bletchley” as an anagram of those letters, which made me think that the whole string is a collection of anagrams, perhaps each bit of the URL forming its own anagram.

Enough staring at this actually reveals it’s easier than that… (especially staring at the full-stops given this is obviously a URL!). If you simply swap every pair of letters back-to-front, starting at the front you reveal the answer. i.e. swap “ww” to get “ww”, swap “.w” to get “w.”, swap “ht” to get “th” and so on.

Finally I have solved stage 2: www.thisisgloucestershire.co.uk/bletchley which does indeed take me to the next stage of the puzzle! Hurrah. Direct link http://www.thisisgloucestershire.co.uk/bletchley

[I’m still worried about the rest of the information in the RSA key… I wonder if I’ll need it later?]

My final success of stage 2 is realising that the final part of the URL (for both stage 1 and stage 2) are actually the answers required on the challenge website: https://canyoufindit.co.uk/ Up till now I’d assumed I’d find all five answers “when I got to the end”. I guess that means there are 5 stages then!

Onto stage 3

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GCHQ Challenge - Stage 2

Cracking the code

Stage 2