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PKCS7_ENCRYPT(3ossl)		    OpenSSL		  PKCS7_ENCRYPT(3ossl)

       PKCS7_encrypt_ex, PKCS7_encrypt - create	a PKCS#7 envelopedData

	#include <openssl/pkcs7.h>

	PKCS7 *PKCS7_encrypt_ex(STACK_OF(X509) *certs, BIO *in,
				const EVP_CIPHER *cipher, int flags,
				OSSL_LIB_CTX *libctx, const char *propq);
	PKCS7 *PKCS7_encrypt(STACK_OF(X509) *certs, BIO	*in, const EVP_CIPHER *cipher,
			     int flags);

       PKCS7_encrypt_ex() creates and returns a	PKCS#7 envelopedData
       structure.  certs is a list of recipient	certificates. in is the
       content to be encrypted.	cipher is the symmetric	cipher to use. flags
       is an optional set of flags. The	library	context	libctx and the
       property	query propq are	used when retrieving algorithms	from

       Only RSA	keys are supported in PKCS#7 and envelopedData so the
       recipient certificates supplied to this function	must all contain RSA
       public keys, though they	do not have to be signed using the RSA

       EVP_des_ede3_cbc() (triple DES) is the algorithm	of choice for S/MIME
       use because most	clients	will support it.

       Some old	"export	grade" clients may only	support	weak encryption	using
       40 or 64	bit RC2. These can be used by passing EVP_rc2_40_cbc() and
       EVP_rc2_64_cbc()	respectively.

       The algorithm passed in the cipher parameter must support ASN1 encoding
       of its parameters.

       Many browsers implement a "sign and encrypt" 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 BIO
       and passing it to PKCS7_encrypt().

       The following flags can be passed in the	flags parameter.

       If the PKCS7_TEXT flag is set MIME headers for type text/plain are
       prepended to the	data.

       Normally	the supplied content is	translated into	MIME canonical format
       (as required by the S/MIME specifications) if PKCS7_BINARY 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
       PKCS7_BINARY is set then	PKCS7_TEXT is ignored.

       If the PKCS7_STREAM flag	is set a partial PKCS7 structure is output
       suitable	for streaming I/O: no data is read from	the BIO	in.

       If the flag PKCS7_STREAM	is set the returned PKCS7 structure is not
       complete	and outputting its contents via	a function that	does not
       properly	finalize the PKCS7 structure will give unpredictable results.

       Several functions including SMIME_write_PKCS7(),
       i2d_PKCS7_bio_stream(), PEM_write_bio_PKCS7_stream() finalize the
       structure. Alternatively	finalization can be performed by obtaining the
       streaming ASN1 BIO directly using BIO_new_PKCS7().

       PKCS7_encrypt() is similar to PKCS7_encrypt_ex()	but uses default
       values of NULL for the library context libctx and the property query

       PKCS7_encrypt_ex() and PKCS7_encrypt() return either a PKCS7 structure
       or NULL if an error occurred. The error can be obtained from

       ERR_get_error(3), PKCS7_decrypt(3)

       The function PKCS7_encrypt_ex() was added in OpenSSL 3.0.

       The PKCS7_STREAM	flag was added in OpenSSL 1.0.0.

       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

3.0.0-beta1+quic		  2021-06-19		  PKCS7_ENCRYPT(3ossl)


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