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SMIME_READ_PKCS7(3ossl) OpenSSL SMIME_READ_PKCS7(3ossl)
NAME
SMIME_read_PKCS7_ex, SMIME_read_PKCS7 - parse S/MIME message
SYNOPSIS
#include <openssl/pkcs7.h>
PKCS7 *SMIME_read_PKCS7_ex(BIO *bio, BIO **bcont, PKCS7 **p7);
PKCS7 *SMIME_read_PKCS7(BIO *in, BIO **bcont);
DESCRIPTION
SMIME_read_PKCS7() parses a message in S/MIME format.
in is a BIO to read the message from.
If cleartext signing is used then the content is saved in a memory bio
which is written to *bcont, otherwise *bcont is set to NULL.
The parsed PKCS#7 structure is returned or NULL if an error occurred.
SMIME_read_PKCS7_ex() is similar to SMIME_read_PKCS7() but can
optionally supply a previously created p7 PKCS#7 object. If p7 is NULL
then it is identical to SMIME_read_PKCS7(). To create a p7 object use
PKCS7_new_ex(3).
NOTES
If *bcont is not NULL then the message is clear text signed. *bcont can
then be passed to PKCS7_verify() with the PKCS7_DETACHED flag set.
Otherwise the type of the returned structure can be determined using
PKCS7_type_is_enveloped(), etc.
To support future functionality if bcont is not NULL *bcont should be
initialized to NULL. For example:
BIO *cont = NULL;
PKCS7 *p7;
p7 = SMIME_read_PKCS7(in, &cont);
BUGS
The MIME parser used by SMIME_read_PKCS7() is somewhat primitive.
While it will handle most S/MIME messages more complex compound formats
may not work.
The parser assumes that the PKCS7 structure is always base64 encoded
and will not handle the case where it is in binary format or uses
quoted printable format.
The use of a memory BIO to hold the signed content limits the size of
message which can be processed due to memory restraints: a streaming
single pass option should be available.
RETURN VALUES
SMIME_read_PKCS7_ex() and SMIME_read_PKCS7() return a valid PKCS7
structure or NULL if an error occurred. The error can be obtained from
ERR_get_error(3).
COPYRIGHT
Copyright 2002-2020 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (the "License"). You may not use
this file except in compliance with the License. You can obtain a copy
in the file LICENSE in the source distribution or at
<https://www.openssl.org/source/license.html>.
3.0.11 2023-09-19 SMIME_READ_PKCS7(3ossl)