Tue Jul 30 09:21:43 2002
Standard preamble:
======================================================================
\\$1
.. ..
.... Set up some character translations and predefined strings. \*(-- will
give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
double quote, and \*(R" will give a right double quote. | will give a
real vertical bar. \*(C+ will give a nicer C++. Capital omega is used
to do unbreakable dashes and therefore won't be available. \*(C` and
\*(C' expand to `' in nroff, nothing in troff, for use with C<>
.tr \(*W-|\(bv\*(Tr . ds -- \(*W- . ds PI pi . if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch . if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch . ds L" "" . ds R" "" . ds C` "" . ds C' "" 'br\} . ds -- \|\(em\| . ds PI \(*p . ds L" `` . ds R" '' 'br\}
If the F register is turned on, we'll generate index entries on stderr
for titles (.TH), headers (.SH), subsections (.Sh), items (.Ip), and
index entries marked with X<> in POD. Of course, you'll have to process
the output yourself in some meaningful fashion.
. de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . nr % 0 . rr F .\}
For nroff, turn off justification. Always turn off hyphenation; it
makes way too many mistakes in technical documents.
Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2).
Fear. Run. Save yourself. No user-serviceable parts.
.bd B 3 . \" fudge factors for nroff and troff . ds #H 0 . ds #V .8m . ds #F .3m . ds #[ \f1 . ds #] .\} . ds #H ((1u-(\\\\n(.fu%2u))*.13m) . ds #V .6m . ds #F 0 . ds #[ \& . ds #] \& .\} . \" simple accents for nroff and troff . ds ' \& . ds ` \& . ds ^ \& . ds , \& . ds ~ ~ . ds / .\} . ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u" . ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u' . ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u' . ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u' . ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u' . ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u' .\} . \" troff and (daisy-wheel) nroff accents . \" corrections for vroff . \" for low resolution devices (crt and lpr) \{\ . ds : e . ds 8 ss . ds o a . ds d- d\h'-1'\(ga . ds D- D\h'-1'\(hy . ds th \o'bp' . ds Th \o'LP' . ds ae ae . ds Ae AE .\} ======================================================================
Title "EVP_SignInit 3"
\fIEVP_SignInit() initializes a signing context ctx to using digest \fBtype: this will typically be supplied by a function such as \fIEVP_sha1().
\fIEVP_SignUpdate() hashes cnt bytes of data at d into the signature context ctx. This function can be called several times on the same ctx to include additional data.
\fIEVP_SignFinal() signs the data in ctx using the private key pkey and places the signature in sig. If the s parameter is not \s-1NULL\s0 then the number of bytes of data written (i.e. the length of the signature) will be written to the integer at s, at most EVP_PKEY_size(pkey) bytes will be written. After calling EVP_SignFinal() no additional calls to \fIEVP_SignUpdate() can be made, but EVP_SignInit() can be called to initialize a new signature operation.
\fIEVP_PKEY_size() returns the maximum size of a signature in bytes. The actual signature returned by EVP_SignFinal() may be smaller.
\fIEVP_SignFinal() returns 1 for success and 0 for failure.
\fIEVP_PKEY_size() returns the maximum size of a signature in bytes.
The error codes can be obtained by ERR_get_error(3).
Due to the link between message digests and public key algorithms the correct digest algorithm must be used with the correct public key type. A list of algorithms and associated public key algorithms appears in EVP_DigestInit(3).
When signing with \s-1DSA\s0 private keys the random number generator must be seeded or the operation will fail. The random number generator does not need to be seeded for \s-1RSA\s0 signatures.