=head1 NAME
-BIO_new_CMS - CMS streaming filter BIO
+ BIO_new_CMS - CMS streaming filter BIO
=head1 SYNOPSIS
=head1 DESCRIPTION
BIO_new_CMS() returns a streaming filter BIO chain based on B<cms>. The output
-of the filter is written to B<out>. Any data written to the returned BIO
-is automatically translated to a BER format CMS structure.
+of the filter is written to B<out>. Any data written to the chain is
+automatically translated to a BER format CMS structure of the appropriate type.
=head1 NOTES
-The BIO returned by this functions behaves like a standard filter BIO. It
-supports non blocking I/O. Content is processes and streamed on the fly and not
+The chain returned by this function behaves like a standard filter BIO. It
+supports non blocking I/O. Content is processed and streamed on the fly and not
all held in memory at once: so it is possible to encode very large structures.
-After all content has been written through the BIO BIO_flush() must be called
+After all content has been written through the chain BIO_flush() must be called
to finalise the structure.
The B<CMS_STREAM> flag must be included in the corresponding B<flags>
parameter of the B<cms> creation function.
-After use BIOs should be removed from the filter using BIO_pop() until
-the output BIO B<out> is reached.
+If an application wishes to write additional data to B<out> BIOs should be
+removed from the chain using BIO_pop() and freed with BIO_free() until B<out>
+is reached. If no additional data needs to be written BIO_free_all() can be
+called to free up the whole chain.
-Any content written through the filter is uses "as-is" and no canonical
+Any content written through the filter is used verbatim: no canonical
translation is performed.
-It is possible to chain multiple BIOs to for example create a triple wrapped
-signed, enveloped signed structure. In this case it is the applications
+It is possible to chain multiple BIOs to, for example, create a triple wrapped
+signed, enveloped, signed structure. In this case it is the applications
responsibility to set the inner content type of any outer CMS_ContentInfo
structures.
=head1 DESCRIPTION
-CMS_add0_cert() and CMS_add1_cert() add certificate B<cert> to B<cms> which
+CMS_add0_cert() and CMS_add1_cert() add certificate B<cert> to B<cms>.
must be of type signed data or enveloped data.
CMS_get1_certs() returns all certificates in B<cms>.
-CMS_add0_crl() adds CRL B<crl> to B<cms> which must be of type signed data or
-enveloped data. CMS_get1_crls() returns any CRLs in B<cms>.
+CMS_add0_crl() adds CRL B<crl> to B<cms>. CMS_get1_crls() returns any CRLs in
+B<cms>.
=head1 NOTES
+The CMS_ContentInfo structure B<cms> must be of type signed data or enveloped
+data or an error will be returned.
+
+For signed data certificates and CRLs are added to the B<certificates> and
+B<crls> fields of SignedData structure. For enveloped data they are added to
+B<OriginatorInfo>.
+
As the B<0> implies CMS_add0_cert() adds B<cert> internally to B<cms> and it
must not be freed up after the call as opposed to CMS_add1_cert() where B<cert>
must be freed up.
The same certificate or CRL must not be added to the same cms structure more
than once.
-For signed data CMS types certificates and CRLs are added to the
-B<certificates> and B<crls> fields of the SignedData structure. For enveloped
-data they are added to B<OriginatorInfo>.
-
=head1 RETURN VALUES
CMS_add0_cert(), CMS_add1_cert() and CMS_add0_crl() return 1 for success and
=head1 SEE ALSO
-L<ERR_get_error(3)|ERR_get_error(3)>
+L<ERR_get_error(3)|ERR_get_error(3)>,
+L<CMS_sign(3)|CMS_sign(3)>,
+L<CMS_encrypt(3)|CMS_encrypt(3)>
=head1 HISTORY
=head1 DESCRIPTION
-CMS_add1_recipient_cert() adds a recipient certificate B<recip>
-CMS_ContentInfo enveloped data structure B<cms> as a KeyTransRecipientInfo
-structure.
+CMS_add1_recipient_cert() adds recipient B<recip> to CMS_ContentInfo enveloped
+data structure B<cms> as a KeyTransRecipientInfo structure.
CMS_add0_recipient_key() adds symmetric key B<key> of length B<keylen> using
-wrapping algorithm B<nid>, identifier B<id> or length B<idlen> and optional
+wrapping algorithm B<nid>, identifier B<id> of length B<idlen> and optional
values B<date>, B<otherTypeId> and B<otherType> to CMS_ContentInfo enveloped
data structure B<cms> as a KEKRecipientInfo structure.
CMS_compress() creates and returns a CMS CompressedData structure. B<comp_nid>
is the compression algorithm to use or B<NID_undef> to use the default
-algorithms (zlib compression). B<in> is the content to be compressed.
+algorithm (zlib compression). B<in> is the content to be compressed.
B<flags> is an optional set of flags.
=head1 NOTES
The only currently supported compression algorithm is zlib using the NID
NID_zlib_compression.
-If zlib support is not compiled into OpenSSL this CMS_compress() will return
+If zlib support is not compiled into OpenSSL then CMS_compress() will return
an error.
If the B<CMS_TEXT> flag is set MIME headers for type B<text/plain> are
=head1 NAME
-CMS_decrypt - decrypt content from a CMS envelopedData structure
+ CMS_decrypt - decrypt content from a CMS envelopedData structure
=head1 SYNOPSIS
=head1 DESCRIPTION
-CMS_decrypt() extracts and decrypts the content from a CMS envelopedData
+CMS_decrypt() extracts and decrypts the content from a CMS EnvelopedData
structure. B<pkey> is the private key of the recipient, B<cert> is the
-recipients certificate, B<data> is a BIO to write the content to and
+recipient's certificate, B<data> is a BIO to write the content to and
B<flags> is an optional set of flags.
The B<dcont> parameter is used in the rare case where the encrypted content
in advance using the CMS utility functions such as CMS_set1_pkey(). In this
case both B<cert> and B<pkey> should be set to NULL.
-To process KEKRecipientInfo types CMS_set1_key() should be used and B<cert>
-and B<pkey> set to NULL.
+To process KEKRecipientInfo types CMS_set1_key() or CMS_RecipientInfo_set0_key()
+and CMS_ReceipientInfo_decrypt() should be called before CMS_decrypt() and
+B<cert> and B<pkey> set to NULL.
The following flags can be passed in the B<flags> parameter.
=head1 NAME
-CMS_encrypt - create a CMS envelopedData structure
+ CMS_encrypt - create a CMS envelopedData structure
=head1 SYNOPSIS
=head1 DESCRIPTION
-CMS_encrypt() creates and returns a CMS envelopedData structure. B<certs>
+CMS_encrypt() creates and returns a CMS EnvelopedData structure. B<certs>
is a list of recipient certificates. B<in> is the content to be encrypted.
B<cipher> is the symmetric cipher to use. B<flags> is an optional set of flags.
=head1 NOTES
-Only certificates carrying RSA keys are supported in CMS 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 algorithm.
+Only certificates carrying RSA keys are supported 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 algorithm.
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 B<cipher> parameter must support ASN1 encoding of
its parameters.
=head1 NAME
-CMS_final - finalise a CMS_ContentInfo structure
+ CMS_final - finalise a CMS_ContentInfo structure
=head1 SYNOPSIS
=head1 NAME
-CMS_get0_RecipientInfos, CMS_RecipientInfo_type, CMS_RecipientInfo_ktri_get0_signer_id,CMS_RecipientInfo_ktri_cert_cmp, CMS_RecipientInfo_set0_pkey, CMS_RecipientInfo_kekri_get0_id, CMS_RecipientInfo_kekri_id_cmp, CMS_RecipientInfo_set0_key, CMS_RecipientInfo_decrypt - CMS envelopedData RecipientInfo routines
+ CMS_get0_RecipientInfos, CMS_RecipientInfo_type, CMS_RecipientInfo_ktri_get0_signer_id,CMS_RecipientInfo_ktri_cert_cmp, CMS_RecipientInfo_set0_pkey, CMS_RecipientInfo_kekri_get0_id, CMS_RecipientInfo_kekri_id_cmp, CMS_RecipientInfo_set0_key, CMS_RecipientInfo_decrypt - CMS envelopedData RecipientInfo routines
=head1 SYNOPSIS
=head1 DESCRIPTION
The function CMS_get0_RecipientInfos() returns all the CMS_RecipientInfo
-structures associated with a CMS envelopedData structure.
+structures associated with a CMS EnvelopedData structure.
CMS_RecipientInfo_type() returns the type of CMS_RecipientInfo structure B<ri>.
It will currently return CMS_RECIPINFO_TRANS, CMS_RECIPINFO_AGREE,
using CMS_get0_RecipientInfos() and check the type of each using
CMS_RecpientInfo_type(). Depending on the type the CMS_RecipientInfo structure
can be ignored or its key identifier data retrieved using an appropriate
-function. Then if the corresponding secret or private key can be obtained by
+function. Then if the corresponding secret or private key can be obtained by
any appropriate means it can then associated with the structure and
CMS_RecpientInfo_decrypt() called. If successful CMS_decrypt() can be called
with a NULL key to decrypt the enveloped content.
=head1 NAME
-CMS_get0_SignerInfos, CMS_SignerInfo_get0_signer_id, CMS_SignerInfo_cert_cmp, CMS_set1_signer_certs - CMS signedData signer functions.
+ CMS_get0_SignerInfos, CMS_SignerInfo_get0_signer_id, CMS_SignerInfo_cert_cmp, CMS_set1_signer_certs - CMS signedData signer functions.
=head1 SYNOPSIS
STACK_OF(CMS_SignerInfo) *CMS_get0_SignerInfos(CMS_ContentInfo *cms);
- int CMS_SignerInfo_get0_signer_id(CMS_SignerInfo *si,
- ASN1_OCTET_STRING **keyid,
- X509_NAME **issuer, ASN1_INTEGER **sno);
+ int CMS_SignerInfo_get0_signer_id(CMS_SignerInfo *si, ASN1_OCTET_STRING **keyid, X509_NAME **issuer, ASN1_INTEGER **sno);
int CMS_SignerInfo_cert_cmp(CMS_SignerInfo *si, X509 *cert);
void CMS_SignerInfo_set1_signer_cert(CMS_SignerInfo *si, X509 *signer);
#include <openssl/cms.h>
-CMS_ReceiptRequest *CMS_ReceiptRequest_create0(unsigned char *id, int idlen, int allorfirst, STACK_OF(GENERAL_NAMES) *receiptList, STACK_OF(GENERAL_NAMES) *receiptsTo);
-int CMS_add1_ReceiptRequest(CMS_SignerInfo *si, CMS_ReceiptRequest *rr);
-int CMS_get1_ReceiptRequest(CMS_SignerInfo *si, CMS_ReceiptRequest **prr);
-void CMS_ReceiptRequest_get0_values(CMS_ReceiptRequest *rr, ASN1_STRING **pcid, int *pallorfirst, STACK_OF(GENERAL_NAMES) **plist, STACK_OF(GENERAL_NAMES) **prto);
+ CMS_ReceiptRequest *CMS_ReceiptRequest_create0(unsigned char *id, int idlen, int allorfirst, STACK_OF(GENERAL_NAMES) *receiptList, STACK_OF(GENERAL_NAMES) *receiptsTo);
+ int CMS_add1_ReceiptRequest(CMS_SignerInfo *si, CMS_ReceiptRequest *rr);
+ int CMS_get1_ReceiptRequest(CMS_SignerInfo *si, CMS_ReceiptRequest **prr);
+ void CMS_ReceiptRequest_get0_values(CMS_ReceiptRequest *rr, ASN1_STRING **pcid, int *pallorfirst, STACK_OF(GENERAL_NAMES) **plist, STACK_OF(GENERAL_NAMES) **prto);
=head1 DESCRIPTION
=head1 HISTORY
-CMS_ReceiptRequest_create0(), CMS_add1_ReceiptRequest(), CMS_get1_ReceiptRequest() and CMS_ReceiptRequest_get0_values() were
-added to OpenSSL 0.9.8
+CMS_ReceiptRequest_create0(), CMS_add1_ReceiptRequest(),
+CMS_get1_ReceiptRequest() and CMS_ReceiptRequest_get0_values() were added to
+OpenSSL 0.9.8
=cut
=head1 NAME
-CMS_sign - create a CMS SignedData structure
+ CMS_sign - create a CMS SignedData structure
=head1 SYNOPSIS
omitted.
If present the SMIMECapabilities attribute indicates support for the following
-algorithms: triple DES, 128 bit RC2, 64 bit RC2, DES and 40 bit RC2. If any of
-these algorithms is disabled then it will not be included.
+algorithms in preference order: 256 bit AES, Gost R3411-94, Gost 28147-89, 192
+bit AES, 128 bit AES, triple DES, 128 bit RC2, 64 bit RC2, DES and 40 bit RC2.
+If any of these algorithms is not available then it will not be included: for example the GOST algorithms will not be included if the GOST ENGINE is
+not loaded.
OpenSSL will by default identify signing certificates using issuer name
and serial number. If B<CMS_USE_KEYID> is set it will use the subject key
suitable for many purposes. For finer control of the output format the
B<certs>, B<signcert> and B<pkey> parameters can all be B<NULL> and the
B<CMS_PARTIAL> flag set. Then one or more signers can be added using the
-function B<CMS_sign_add1_signer()>, non default digests set and custom
+function CMS_sign_add1_signer(), non default digests can be used and custom
attributes added. B<CMS_final()> must then be called to finalize the
structure if streaming is not enabled.
=head1 BUGS
-Some advanced attributes such as counter signatures are not supported.
+Some attributes such as counter signatures are not supported.
=head1 RETURN VALUES
CMS_sign() returns either a valid CMS_ContentInfo structure or NULL if an error
-occurred. The error can be obtained from ERR_get_error(3).
+occurred. The error can be obtained from ERR_get_error(3).
=head1 SEE ALSO
=head1 NAME
-CMS_sign_add_signer, CMS_SignerInfo_sign - add a signer to a CMS_ContentInfo signed data structure.
+ CMS_sign_add_signer, CMS_SignerInfo_sign - add a signer to a CMS_ContentInfo signed data structure.
=head1 SYNOPSIS
CMS_SignerInfo *CMS_sign_add1_signer(CMS_ContentInfo *cms, X509 *signcert, EVP_PKEY *pkey, const EVP_MD *md, unsigned int flags);
-int CMS_SignerInfo_sign(CMS_SignerInfo *si);
+ int CMS_SignerInfo_sign(CMS_SignerInfo *si);
=head1 DESCRIPTION
CMS_sign_add1_signer() adds a signer with certificate B<signcert> and private
-key B<pkey> using message digest B<md> to CMS_ContentInfo signed data
+key B<pkey> using message digest B<md> to CMS_ContentInfo SignedData
structure B<cms>.
The CMS_ContentInfo structure should be obtained from an initial call to
CMS_sign() with the flag B<CMS_PARTIAL> set or in the case or re-signing a
-valid CMS_ContentInfo signed data structure.
+valid CMS_ContentInfo SignedData structure.
If the B<md> parameter is B<NULL> then the default digest for the public
key algorithm will be used.
=head1 NOTES
-The main purpose of this CMS_sign_add1_signer() is to provide finer control
+The main purpose of CMS_sign_add1_signer() is to provide finer control
over a CMS signed data structure where the simpler CMS_sign() function defaults
are not appropriate. For example if multiple signers or non default digest
algorithms are needed. New attributes can also be added using the returned
the signers certificate can be obtained by other means: for example a
previously signed message.
-The signedData structure includes several CMS signedAttributes including the
+The SignedData structure includes several CMS signedAttributes including the
signing time, the CMS content type and the supported list of ciphers in an
SMIMECapabilities attribute. If B<CMS_NOATTR> is set then no signedAttributes
will be used. If B<CMS_NOSMIMECAP> is set then just the SMIMECapabilities are
=head1 NAME
-CMS_sign_receipt - create a CMS signed receipt
+ CMS_sign_receipt - create a CMS signed receipt
=head1 SYNOPSIS
=head1 NAME
-CMS_uncompress - uncompress a CMS CompressedData structure
+ CMS_uncompress - uncompress a CMS CompressedData structure
=head1 SYNOPSIS
=head1 NOTES
-The only currently supported compression algorithm is zlib if the structure
-indicates the use of any other algorithm and error is returned.
+The only currently supported compression algorithm is zlib: if the structure
+indicates the use of any other algorithm an error is returned.
If zlib support is not compiled into OpenSSL then CMS_uncompress() will always
return an error.
=head1 NAME
-CMS_verify - verify a CMS SignedData structure
+ CMS_verify - verify a CMS SignedData structure
=head1 SYNOPSIS
CMS_verify() verifies a CMS SignedData structure. B<cms> is the CMS_ContentInfo
structure to verify. B<certs> is a set of certificates in which to search for
-the signer's certificate. B<store> is a trusted certificate store (used for
-chain verification). B<indata> is the signed data if the content is not
-present in B<cms> (that is it is detached). The content is written to B<out>
-if it is not NULL.
+the signing certificate(s). B<store> is a trusted certificate store used for
+chain verification. B<indata> is the detached content if the content is not
+present in B<cms>. The content is written to B<out> if it is not NULL.
B<flags> is an optional set of flags, which can be used to modify the verify
operation.
-CMS_get0_signers() retrieves the signer's certificate(s) from B<cms>, it must
+CMS_get0_signers() retrieves the signing certificate(s) from B<cms>, it must
be called after a successful CMS_verify() operation.
=head1 VERIFY PROCESS
be SignedData. There must be at least one signature on the data and if
the content is detached B<indata> cannot be B<NULL>.
-An attempt is made to locate all the signer's certificates, first looking in
-the B<certs> parameter (if it is not B<NULL>) and then looking in any
-certificates contained in the B<cms> structure itself. If any signer's
-certificates cannot be located the operation fails.
+An attempt is made to locate all the signing certificate(s), first looking in
+the B<certs> parameter (if it is not NULL) and then looking in any
+certificates contained in the B<cms> structure itself. If any signing
+certificate cannot be located the operation fails.
-Each signer's certificate is chain verified using the B<smimesign> purpose and
+Each signing certificate is chain verified using the B<smimesign> purpose and
the supplied trusted certificate store. Any internal certificates in the message
are used as untrusted CAs. If CRL checking is enabled in B<store> any internal
-CRLs are used in addition to attempting to look the up in B<store>. If any
+CRLs are used in addition to attempting to look them up in B<store>. If any
chain verify fails an error code is returned.
Finally the signed content is read (and written to B<out> is it is not NULL)
Any of the following flags (ored together) can be passed in the B<flags>
parameter to change the default verify behaviour.
-If B<CMS_NOINTERN> is set the certificates in the message itself are not
-searched when locating the signer's certificate. This means that all the signers
-certificates must be in the B<certs> parameter.
+If B<CMS_NOINTERN> is set the certificates in the message itself are not
+searched when locating the signing certificate(s). This means that all the
+signing certificates must be in the B<certs> parameter.
If B<CMS_NOCRL> is set and CRL checking is enabled in B<store> then any
CRLs in the message itself are ignored.
from the content. If the content is not of type B<text/plain> then an error is
returned.
-If B<CMS_NO_SIGNER_CERT_VERIFY> is set the signer's certificates are not
+If B<CMS_NO_SIGNER_CERT_VERIFY> is set the signing certificates are not
verified.
If B<CMS_NO_ATTR_VERIFY> is set the signed attributes signature is not
CMS_verify() returns 1 for a successful verification and zero if an error
occurred.
-CMS_get0_signers() returns all signers or B<NULL> if an error occurred.
+CMS_get0_signers() returns all signers or NULL if an error occurred.
The error can be obtained from L<ERR_get_error(3)|ERR_get_error(3)>
=head1 BUGS
-The trusted certificate store is not searched for the signers certificate,
+The trusted certificate store is not searched for the signing certificate,
this is primarily due to the inadequacies of the current B<X509_STORE>
functionality.
-The lack of single pass processing and need to hold all data in memory as
-mentioned in CMS_sign() also applies to CMS_verify().
+The lack of single pass processing means that the signed content must all
+be held in memory if it is not detached.
=head1 SEE ALSO
=head1 NAME
-CMS_verify - verify a CMS signed receipt
+ CMS_verify_receipt - verify a CMS signed receipt
=head1 SYNOPSIS
CMS_verify_receipt() verifies a CMS signed receipt. B<rcms> is the signed
receipt to verify. B<ocms> is the original SignedData structure containing the
-receipt request B<certs> is a set of certificates in which to search for the
-signer's certificate. B<store> is a trusted certificate store (used for chain
+receipt request. B<certs> is a set of certificates in which to search for the
+signing certificate. B<store> is a trusted certificate store (used for chain
verification).
B<flags> is an optional set of flags, which can be used to modify the verify
=head1 HISTORY
-CMS_verify() was added to OpenSSL 0.9.8
+CMS_verify_receipt() was added to OpenSSL 0.9.8
=cut
=head1 NAME
-PEM_write_bio_CMS_stream - output CMS_ContentInfo structure in PEM format.
+ PEM_write_bio_CMS_stream - output CMS_ContentInfo structure in PEM format.
=head1 SYNOPSIS
=head1 NAME
-SMIME_read_CMS - parse S/MIME message.
+ SMIME_read_CMS - parse S/MIME message.
=head1 SYNOPSIS
B<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 B<*bcont>, otherwise
-B<*bcont> is set to B<NULL>.
+If cleartext signing is used then the content is saved in a memory bio which is
+written to B<*bcont>, otherwise B<*bcont> is set to NULL.
-The parsed CMS_ContentInfo structure is returned or B<NULL> if an
+The parsed CMS_ContentInfo structure is returned or NULL if an
error occurred.
=head1 NOTES
-If B<*bcont> is not B<NULL> then the message is clear text
-signed. B<*bcont> can then be passed to CMS_verify() with
-the B<CMS_DETACHED> flag set.
+If B<*bcont> is not NULL then the message is clear text signed. B<*bcont> can
+then be passed to CMS_verify() with the B<CMS_DETACHED> flag set.
Otherwise the type of the returned structure can be determined
using CMS_get0_type().
-To support future functionality if B<bcont> is not B<NULL>
-B<*bcont> should be initialized to B<NULL>. For example:
+To support future functionality if B<bcont> is not NULL B<*bcont> should be
+initialized to NULL. For example:
BIO *cont = NULL;
CMS_ContentInfo *cms;
=head1 BUGS
-The MIME parser used by SMIME_read_CMS() is somewhat primitive.
-While it will handle most S/MIME messages more complex compound
-formats may not work.
+The MIME parser used by SMIME_read_CMS() is somewhat primitive. While it will
+handle most S/MIME messages more complex compound formats may not work.
-The parser assumes that the CMS_ContentInfo structure is always base64
-encoded and will not handle the case where it is in binary format
-or uses quoted printable format.
+The parser assumes that the CMS_ContentInfo 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.
+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.
=head1 RETURN VALUES
=head1 NAME
-SMIME_write_CMS - convert CMS structure to S/MIME format.
+ SMIME_write_CMS - convert CMS structure to S/MIME format.
=head1 SYNOPSIS
The following flags can be passed in the B<flags> parameter.
-If B<CMS_DETACHED> is set then cleartext signing will be used,
-this option only makes sense for signedData where B<CMS_DETACHED>
-is also set when CMS_sign() is called.
+If B<CMS_DETACHED> is set then cleartext signing will be used, this option only
+makes sense for SignedData where B<CMS_DETACHED> is also set when CMS_sign() is
+called.
-If the B<CMS_TEXT> flag is set MIME headers for type B<text/plain>
-are added to the content, this only makes sense if B<CMS_DETACHED>
-is also set.
+If the B<CMS_TEXT> flag is set MIME headers for type B<text/plain> are added to
+the content, this only makes sense if B<CMS_DETACHED> is also set.
-If the B<CMS_STREAM> flag is set streaming is performed. This flag should
-only be set if B<CMS_STREAM> was also set in the previous call to a
-CMS_ContentInfo creation function.
+If the B<CMS_STREAM> flag is set streaming is performed. This flag should only
+be set if B<CMS_STREAM> was also set in the previous call to a CMS_ContentInfo
+creation function.
-If cleartext signing is being used and B<CMS_STREAM> not set then
-the data must be read twice: once to compute the signature in CMS_sign()
-and once to output the S/MIME message.
+If cleartext signing is being used and B<CMS_STREAM> not set then the data must
+be read twice: once to compute the signature in CMS_sign() and once to output
+the S/MIME message.
If streaming is performed the content is output in BER format using indefinite
length constructed encoding except in the case of signed data with detached
=head1 BUGS
-SMIME_write_CMS() always base64 encodes CMS structures, there
-should be an option to disable this.
+SMIME_write_CMS() always base64 encodes CMS structures, there should be an
+option to disable this.
=head1 RETURN VALUES
=head1 NAME
-i2d_CMS_bio_stream - output CMS_ContentInfo structure in BER format.
+ i2d_CMS_bio_stream - output CMS_ContentInfo structure in BER format.
=head1 SYNOPSIS