Carrier, UTF-8. The line is ASCII, so the bytes are the characters.
Split on spaces. Low bit of byte 0 of each word, in order, first word first.
bits 0-17   numerator of t
bits 18-37 denominator of t
bits 38-41 a   bits 42-45 b   bits 46-49 c   bits 50-53 d
a b c d are four-bit two's complement.

t specializes the Li family, Paper5Cat.HighRank.LiRank31:
y^2 - (L*x + B)*y = x*(x+D)*(x+E),
B = p*q*(L+p+q) - p*E - q*D.
li31ToRecord carries that fibre onto the integral #302 record:
x = u^2 x' + r,   y = u^3 y' + u^2 s x' + t_change.
The integers of the change are in the Haskell. They are not reprinted here.

Over Q(adjoin sqrt 2), AlgSqrt.mkAlg, the door curve is
y^2 = x^3 + (a + b*sqrt(2))*x + (c + d*sqrt(2)).
Check, not the key: the point (sqrt(2), 1+sqrt(2)) is on it.

The sealed block opens with t written numerator, slash, denominator.
Basic auth is user fibre, realm garage.
crypt(3) keeps the first eight characters of that string.