xref: /openssl/doc/man3/SMIME_write_ASN1.pod (revision b4250010)
1=pod
2
3=head1 NAME
4
5SMIME_write_ASN1_ex, SMIME_write_ASN1
6- convert structure to S/MIME format
7
8=head1 SYNOPSIS
9
10 #include <openssl/asn1.h>
11
12 int SMIME_write_ASN1_ex(BIO *out, ASN1_VALUE *val, BIO *data, int flags,
13                         int ctype_nid, int econt_nid,
14                         STACK_OF(X509_ALGOR) *mdalgs, const ASN1_ITEM *it,
15                         OSSL_LIB_CTX *libctx, const char *propq);
16
17 int SMIME_write_ASN1(BIO *out,
18     ASN1_VALUE *val, BIO *data, int flags, int ctype_nid, int econt_nid,
19     STACK_OF(X509_ALGOR) *mdalgs, const ASN1_ITEM *it);
20
21=head1 DESCRIPTION
22
23SMIME_write_ASN1_ex() adds the appropriate MIME headers to an object
24structure to produce an S/MIME message.
25
26I<out> is the BIO to write the data to. I<value> is the appropriate ASN1_VALUE
27structure (either CMS_ContentInfo or PKCS7). If streaming is enabled then the
28content must be supplied via I<data>.
29I<flags> is an optional set of flags. I<ctype_nid> is the NID of the content
30type, I<econt_nid> is the NID of the embedded content type and I<mdalgs> is a
31list of signed data digestAlgorithms. Valid values that can be used by the
32ASN.1 structure I<it> are ASN1_ITEM_rptr(PKCS7) or ASN1_ITEM_rptr(CMS_ContentInfo).
33The library context I<libctx> and the property query I<propq> are used when
34retrieving algorithms from providers.
35
36=head1 NOTES
37
38The higher level functions L<SMIME_write_CMS(3)> and
39L<SMIME_write_PKCS7(3)> should be used instead of SMIME_write_ASN1().
40
41The following flags can be passed in the B<flags> parameter.
42
43If B<CMS_DETACHED> is set then cleartext signing will be used, this option only
44makes sense for SignedData where B<CMS_DETACHED> is also set when the sign()
45method is called.
46
47If the B<CMS_TEXT> flag is set MIME headers for type B<text/plain> are added to
48the content, this only makes sense if B<CMS_DETACHED> is also set.
49
50If the B<CMS_STREAM> flag is set streaming is performed. This flag should only
51be set if B<CMS_STREAM> was also set in the previous call to a CMS_ContentInfo
52or PKCS7 creation function.
53
54If cleartext signing is being used and B<CMS_STREAM> not set then the data must
55be read twice: once to compute the signature in sign method and once to output
56the S/MIME message.
57
58If streaming is performed the content is output in BER format using indefinite
59length constructed encoding except in the case of signed data with detached
60content where the content is absent and DER format is used.
61
62=head1 RETURN VALUES
63
64SMIME_write_ASN1_ex() and SMIME_write_ASN1() return 1 for success or
650 for failure.
66
67=head1 SEE ALSO
68
69L<ERR_get_error(3)>,
70L<SMIME_write_CMS(3)>,
71L<SMIME_write_PKCS7(3)>
72
73=head1 COPYRIGHT
74
75Copyright 2020 The OpenSSL Project Authors. All Rights Reserved.
76
77Licensed under the Apache License 2.0 (the "License").  You may not use
78this file except in compliance with the License.  You can obtain a copy
79in the file LICENSE in the source distribution or at
80L<https://www.openssl.org/source/license.html>.
81
82=cut
83