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SMIME_read_PKCS7(3)                 OpenSSL                SMIME_read_PKCS7(3)

       SMIME_read_PKCS7 - parse S/MIME message

       libcrypto, -lcrypto

        #include <openssl/pkcs7.h>

        PKCS7 *SMIME_read_PKCS7(BIO *in, BIO **bcont);

       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.

       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);

       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.

       SMIME_read_PKCS7() returns a valid PKCS7 structure or NULL if an error
       occurred. The error can be obtained from ERR_get_error(3).

       ERR_get_error(3), SMIME_read_PKCS7(3), PKCS7_sign(3), PKCS7_verify(3),
       PKCS7_encrypt(3) PKCS7_decrypt(3)

       Copyright 2002-2018 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the OpenSSL license (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

1.1.1i                            2018-09-23               SMIME_read_PKCS7(3)