Standard preamble:
========================================================================
..
.... 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. \*(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- . 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" '' . ds C` . ds C' 'br\}
Escape single quotes in literal strings from groff's Unicode transform.
If the F register is >0, we'll generate index entries on stderr for
titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
entries marked with X<> in POD. Of course, you'll have to process the
output yourself in some meaningful fashion.
Avoid warning from groff about undefined register 'F'.
.. .nr rF 0 . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF
Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2).
Fear. Run. Save yourself. No user-serviceable parts.
. \" 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 "CMS_ENCRYPT 3"
way too many mistakes in technical documents.
\fBEVP_des_ede3_cbc() (triple \s-1DES\s0) is the algorithm of choice for S/MIME use because most clients will support it.
The algorithm passed in the cipher parameter must support \s-1ASN1\s0 encoding of its parameters.
Many browsers implement a \*(L"sign and encrypt\*(R" option which is simply an S/MIME envelopedData containing an S/MIME signed message. This can be readily produced by storing the S/MIME signed message in a memory \s-1BIO\s0 and passing it to \fBCMS_encrypt().
The following flags can be passed in the flags parameter.
If the \s-1CMS_TEXT\s0 flag is set \s-1MIME\s0 headers for type text/plain are prepended to the data.
Normally the supplied content is translated into \s-1MIME\s0 canonical format (as required by the S/MIME specifications) if \s-1CMS_BINARY\s0 is set no translation occurs. This option should be used if the supplied data is in binary format otherwise the translation will corrupt it. If \s-1CMS_BINARY\s0 is set then \fB\s-1CMS_TEXT\s0 is ignored.
OpenSSL will by default identify recipient certificates using issuer name and serial number. If \s-1CMS_USE_KEYID\s0 is set it will use the subject key identifier value instead. An error occurs if all recipient certificates do not have a subject key identifier extension.
If the \s-1CMS_STREAM\s0 flag is set a partial CMS_ContentInfo structure is returned suitable for streaming I/O: no data is read from the \s-1BIO\s0 in.
If the \s-1CMS_PARTIAL\s0 flag is set a partial CMS_ContentInfo structure is returned to which additional recipients and attributes can be added before finalization.
The data being encrypted is included in the CMS_ContentInfo structure, unless \fB\s-1CMS_DETACHED\s0 is set in which case it is omitted. This is rarely used in practice and is not supported by SMIME_write_CMS().
Several functions including SMIME_write_CMS(), i2d_CMS_bio_stream(), \fBPEM_write_bio_CMS_stream() finalize the structure. Alternatively finalization can be performed by obtaining the streaming \s-1ASN1\s0 \s-1BIO\s0 directly using \fBBIO_new_CMS().
The recipients specified in certs use a \s-1CMS\s0 KeyTransRecipientInfo info structure. KEKRecipientInfo is also supported using the flag \s-1CMS_PARTIAL\s0 and CMS_add0_recipient_key().
The parameter certs may be \s-1NULL\s0 if \s-1CMS_PARTIAL\s0 is set and recipients added later using CMS_add1_recipient_cert() or CMS_add0_recipient_key().
Licensed under the OpenSSL license (the \*(L"License\*(R"). You may not use this file except in compliance with the License. You can obtain a copy in the file \s-1LICENSE\s0 in the source distribution or at <https://www.openssl.org/source/license.html>.