1SMIME_READ_PKCS7(3ossl)             OpenSSL            SMIME_READ_PKCS7(3ossl)
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NAME

6       SMIME_read_PKCS7_ex, SMIME_read_PKCS7 - parse S/MIME message
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SYNOPSIS

9        #include <openssl/pkcs7.h>
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11        PKCS7 *SMIME_read_PKCS7_ex(BIO *bio, BIO **bcont, PKCS7 **p7);
12        PKCS7 *SMIME_read_PKCS7(BIO *in, BIO **bcont);
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DESCRIPTION

15       SMIME_read_PKCS7() parses a message in S/MIME format.
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17       in is a BIO to read the message from.
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19       If cleartext signing is used then the content is saved in a memory bio
20       which is written to *bcont, otherwise *bcont is set to NULL.
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22       The parsed PKCS#7 structure is returned or NULL if an error occurred.
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24       SMIME_read_PKCS7_ex() is similar to SMIME_read_PKCS7() but can
25       optionally supply a previously created p7 PKCS#7 object. If p7 is NULL
26       then it is identical to SMIME_read_PKCS7().  To create a p7 object use
27       PKCS7_new_ex(3).
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NOTES

30       If *bcont is not NULL then the message is clear text signed. *bcont can
31       then be passed to PKCS7_verify() with the PKCS7_DETACHED flag set.
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33       Otherwise the type of the returned structure can be determined using
34       PKCS7_type_is_enveloped(), etc.
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36       To support future functionality if bcont is not NULL *bcont should be
37       initialized to NULL. For example:
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39        BIO *cont = NULL;
40        PKCS7 *p7;
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42        p7 = SMIME_read_PKCS7(in, &cont);
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BUGS

45       The MIME parser used by SMIME_read_PKCS7() is somewhat primitive.
46       While it will handle most S/MIME messages more complex compound formats
47       may not work.
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49       The parser assumes that the PKCS7 structure is always base64 encoded
50       and will not handle the case where it is in binary format or uses
51       quoted printable format.
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53       The use of a memory BIO to hold the signed content limits the size of
54       message which can be processed due to memory restraints: a streaming
55       single pass option should be available.
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RETURN VALUES

58       SMIME_read_PKCS7_ex() and SMIME_read_PKCS7() return a valid PKCS7
59       structure or NULL if an error occurred. The error can be obtained from
60       ERR_get_error(3).
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SEE ALSO

63       ERR_get_error(3), SMIME_read_PKCS7(3), PKCS7_sign(3), PKCS7_verify(3),
64       PKCS7_encrypt(3) PKCS7_decrypt(3)
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HISTORY

67       The function SMIME_read_PKCS7_ex() was added in OpenSSL 3.0.
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70       Copyright 2002-2020 The OpenSSL Project Authors. All Rights Reserved.
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72       Licensed under the Apache License 2.0 (the "License").  You may not use
73       this file except in compliance with the License.  You can obtain a copy
74       in the file LICENSE in the source distribution or at
75       <https://www.openssl.org/source/license.html>.
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793.1.1                             2023-08-31           SMIME_READ_PKCS7(3ossl)
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