smime_write_pkcs7(3openssl) [opensolaris man page]

SMIME_write_PKCS7(3openssl)					      OpenSSL					       SMIME_write_PKCS7(3openssl)

NAME

       SMIME_write_PKCS7 - convert PKCS#7 structure to S/MIME format.

SYNOPSIS

       int SMIME_write_PKCS7(BIO *out, PKCS7 *p7, BIO *data, int flags);

DESCRIPTION

       SMIME_write_PKCS7() adds the appropriate MIME headers to a PKCS#7 structure to produce an S/MIME message.

       out is the BIO to write the data to. p7 is the appropriate PKCS7 structure. If cleartext signing (multipart/signed) is being used then the
       signed data must be supplied in the data argument. flags is an optional set of flags.

NOTES

       The following flags can be passed in the flags parameter.

       If PKCS7_DETACHED is set then cleartext signing will be used, this option only makes sense for signedData where PKCS7_DETACHED is also set
       when PKCS7_sign() is also called.

       If the PKCS7_TEXT flag is set MIME headers for type text/plain are added to the content, this only makes sense if PKCS7_DETACHED is also
       set.

       If the PKCS7_PARTSIGN flag is set the signed data is finalized and output along with the content. This flag should only be set if
       PKCS7_DETACHED is also set and the previous call to PKCS7_sign() also set these flags.

       If cleartext signing is being used and PKCS7_PARTSIGN not set then the data must be read twice: once to compute the signature in
       PKCS7_sign() and once to output the S/MIME message.

BUGS

       SMIME_write_PKCS7() always base64 encodes PKCS#7 structures, there should be an option to disable this.

RETURN VALUES

       SMIME_write_PKCS7() returns 1 for success or 0 for failure.

SEE ALSO

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

HISTORY

       SMIME_write_PKCS7() was added to OpenSSL 0.9.5

OpenSSL-0.9.8							    Oct 11 2005 				       SMIME_write_PKCS7(3openssl)

PKCS7_sign(3)							      OpenSSL							     PKCS7_sign(3)

NAME

       PKCS7_sign - create a PKCS#7 signedData structure

SYNOPSIS

	#include <openssl/pkcs7.h>

	PKCS7 *PKCS7_sign(X509 *signcert, EVP_PKEY *pkey, STACK_OF(X509) *certs, BIO *data, int flags);

DESCRIPTION

       PKCS7_sign() creates and returns a PKCS#7 signedData structure. signcert is the certificate to sign with, pkey is the corresponsding
       private key.  certs is an optional additional set of certificates to include in the PKCS#7 structure (for example any intermediate CAs in
       the chain).

       The data to be signed is read from BIO data.

       flags is an optional set of flags.

NOTES

       Any of the following flags (ored together) can be passed in the flags parameter.

       Many S/MIME clients expect the signed content to include valid MIME headers. If the PKCS7_TEXT flag is set MIME headers for type text/plain
       are prepended to the data.

       If PKCS7_NOCERTS is set the signer's certificate will not be included in the PKCS7 structure, the signer's certificate must still be
       supplied in the signcert parameter though. This can reduce the size of the signature if the signers certificate can be obtained by other
       means: for example a previously signed message.

       The data being signed is included in the PKCS7 structure, unless PKCS7_DETACHED is set in which case it is omitted. This is used for PKCS7
       detached signatures which are used in S/MIME plaintext signed messages for example.

       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.

       The signedData structure includes several PKCS#7 autenticatedAttributes including the signing time, the PKCS#7 content type and the
       supported list of ciphers in an SMIMECapabilities attribute. If PKCS7_NOATTR is set then no authenticatedAttributes will be used. If
       PKCS7_NOSMIMECAP is set then just the SMIMECapabilities are 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.

       If the flags PKCS7_PARTSIGN is set then the returned PKCS7 structure is just initialized ready to perform the signing operation. The
       signing is however not performed and the data to be signed is not read from the data parameter. Signing is deferred until after the data
       has been written. In this way data can be signed in a single pass. Currently the flag PKCS7_DETACHED must also be set.

NOTES

       Currently the flag PKCS7_PARTSIGN is only supported for detached data. If this flag 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.

       At present only the SMIME_write_PKCS7() function properly finalizes the structure.

BUGS

       PKCS7_sign() is somewhat limited. It does not support multiple signers, some advanced attributes such as counter signatures are not
       supported.

       The SHA1 digest algorithm is currently always used.

       When the signed data is not detached it will be stored in memory within the PKCS7 structure. This effectively limits the size of messages
       which can be signed due to memory restraints. There should be a way to sign data without having to hold it all in memory, this would
       however require fairly major revisions of the OpenSSL ASN1 code.

RETURN VALUES

       PKCS7_sign() returns either a valid PKCS7 structure or NULL if an error occurred.  The error can be obtained from ERR_get_error(3).

SEE ALSO

       ERR_get_error(3), PKCS7_verify(3)

HISTORY

       PKCS7_sign() was added to OpenSSL 0.9.5

       The PKCS7_PARTSIGN flag was added in OpenSSL 0.9.8

50								    2013-03-05							     PKCS7_sign(3)