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ref: c116550e6a41572796e4db65e4f6acbcb3d9d6f8
dir: /man/8/ai2key/

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.TH AI2KEY 8
.SH NAME
ai2key, dsagen, rsagen \- generate and reformat public keys
.SH SYNOPSIS
.B ai2key
[
.BI -t " tag"
]
.I keyfile
\&...
.PP
.B dsagen
[
.BI -t " tag"
]
.PP
.B rsagen
[
.BI -b " nbits"
] [
.BI -t " tag"
]
.SH DESCRIPTION
.IR Factotum (4)
represents public keys as lists of attribute-value pairs, each key on a single line prefixed with the string
.BR key .
.PP
.I Ai2key
converts the original Inferno representation of authentication data,
in the format defined for
.B authinfo
by
.IR keytext (6),
to an attribute-value format accepted by
.IR factotum (4)
for the
.B infauth
authentication protocol.
For each
.I keyfile
it writes a single line on standard output, containing
the following fields:
.IP
.EX
.fi
.ti -3n
key proto=infauth
[
.I tag
]
.BI "sigalg=" pkalg - hashalg
[
.BI dom= host
]
.BI server= host
[
.BI service= svc
]
.BI "user=" name
.BI "signer=" name
.BI "pk=" pk
.BI "!sk=" sk
.BI spk= pk
.BI cert= cert
.BI dh-alpha= hex
.BI dh-p= hex
.EE
.PP
where
.RS
.TP 15n
.I pkalg
is
.BR dsa ,
.B elgamal
or
.BR rsa
.PD 0
.ns
.TP
.I hashalg
is
.B md5
or
.BR sha1
.br
.ns
.TP
.B user
is the user name associated with the key, as vouched for by the supporting
certificate
.BR cert
.br
.ns
.TP
.B signer
is the user name associated with the key that signed the certificate
.br
.ns
.TP
.B pk
is the user's public key
.br
.ns
.TP
.B !sk
is the user's private (secret) key
.br
.ns
.TP
.B spk
is the signer's public key
.br
.ns
.TP
.B cert
is the
.I certificate
.br
.ns
.TP
.BR dh-alpha ,\  dh-p
are the Diffie-Hellman parameters shared by the user and file servers.
.RE
.PD
.PP
The key is tagged by one or more of
.BR dom ,
.B server
and
.BR service ,
derived from the file name
.IR keyfile .
The server is
.RB ` * '
if
.I keyfile
is
.BR default .
Otherwise
.I keyfile
has the form
.IP
[
.IB net !
]
.I host
[
.BI ! srv
]
.PP
and
.B server
and
.B service
are set accordingly;
.B dom
is set if
.I host
looks like a domain name.
Key and certificate values have the form defined in
.IR keytext (6);
.I hex
is a large number in hexadecimal.
.PP
.I Dsagen
prints a randomly-generated DSA private key using the NIST-recommended algorithm.
If
.I tag
text is specified, it is printed after the
.B proto
attribute-value pair.
Typically,
.I tag
is a sequence of attribute-value comments describing the key.
A DSA key has the following attributes
.RS
.TP 8n
.B p
prime public modulus
.PD 0
.TP
.B q
prime group order; divides
.BR p -1
.TP
.B alpha
group generator
.TP
.B key
.BR alpha ^ !secret
mod
.B p
.TP
.B !secret
the secret exponent
.RE
.PD
.PP
.I Rsagen
prints a randomly generated RSA private key
whose
.B n
has exactly
.I nbits
(default 1024)
significant bits.
The key has the following attributes:
.RS
.TP
.B size
the number of significant bits in
.B n
.PD 0
.TP
.B ek
the encryption exponent
.TP
.B n
the product of
.B !p
and
.B !q
.TP
.B !dk
the decryption exponent
.TP
.B !p
a large prime
.TP
.B !q
another large prime
.TP
.B "!kp\fR, \fL!kq\fR, \fL!c2
parameters derived from the other attributes, cached to speed decryption
.RE
.PD
.PP
All the numbers in
.I dsagen
and
.I rsagen
output are in hexadecimal except RSA's
.BR size ,
which is decimal.
A public key omits the attributes beginning with
.L ! .
A key may have other attributes as well, for example a
.B service
attribute identifying how this key is typically used,
but to these utilities such attributes are merely comments.
They can be provided in a
.I tag
argument.
.SH SOURCE
.B /appl/cmd/auth/ai2key.b
.br
.B /appl/cmd/auth/dsagen.b
.br
.B /appl/cmd/auth/rsagen.b
.SH "SEE ALSO"
.IR factotum (4)