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cms_encrypt(3ssl) [minix man page]

CMS_encrypt(3SSL)						      OpenSSL							 CMS_encrypt(3SSL)

CMS_encrypt - create a CMS envelopedData structure SYNOPSIS
#include <openssl/cms.h> CMS_ContentInfo *CMS_encrypt(STACK_OF(X509) *certs, BIO *in, const EVP_CIPHER *cipher, unsigned int flags); DESCRIPTION
CMS_encrypt() creates and returns a CMS 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. NOTES
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. 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 CMS_encrypt(). The following flags can be passed in the flags parameter. If the CMS_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 CMS_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 CMS_BINARY is set then CMS_TEXT is ignored. OpenSSL will by default identify recipient certificates using issuer name and serial number. If CMS_USE_KEYID is set it will use the subject key identifier value instead. An error occurs if all recipient certificates do not have a subject key identifier extension. If the CMS_STREAM flag is set a partial CMS_ContentInfo structure is returned suitable for streaming I/O: no data is read from the BIO in. If the CMS_PARTIAL flag is set a partial CMS_ContentInfo structure is returned to which additional recipients and attributes can be added before finalization. The data being encrypted is included in the CMS_ContentInfo structure, unless CMS_DETACHED is set in which case it is omitted. This is rarely used in practice and is not supported by SMIME_write_CMS(). NOTES
If the flag CMS_STREAM is set the returned CMS_ContentInfo structure is not complete and outputting its contents via a function that does not properly finalize the CMS_ContentInfo structure will give unpredictable results. Several functions including SMIME_write_CMS(), i2d_CMS_bio_stream(), PEM_write_bio_CMS_stream() finalize the structure. Alternatively finalization can be performed by obtaining the streaming ASN1 BIO directly using BIO_new_CMS(). The recipients specified in certs use a CMS KeyTransRecipientInfo info structure. KEKRecipientInfo is also supported using the flag CMS_PARTIAL and CMS_add0_recipient_key(). The parameter certs may be NULL if CMS_PARTIAL is set and recipients added later using CMS_add1_recipient_cert() or CMS_add0_recipient_key(). RETURN VALUES
CMS_encrypt() returns either a CMS_ContentInfo structure or NULL if an error occurred. The error can be obtained from ERR_get_error(3). SEE ALSO
ERR_get_error(3), CMS_decrypt(3) HISTORY
CMS_decrypt() was added to OpenSSL 0.9.8 The CMS_STREAM flag was first supported in OpenSSL 1.0.0. 1.0.1e 2013-02-11 CMS_encrypt(3SSL)

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SMIME_write_CMS(3SSL)						      OpenSSL						     SMIME_write_CMS(3SSL)

SMIME_write_CMS - convert CMS structure to S/MIME format. SYNOPSIS
#include <openssl/cms.h> int SMIME_write_CMS(BIO *out, CMS_ContentInfo *cms, BIO *data, int flags); DESCRIPTION
SMIME_write_CMS() adds the appropriate MIME headers to a CMS structure to produce an S/MIME message. out is the BIO to write the data to. cms is the appropriate CMS_ContentInfo structure. If streaming is enabled then the content 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 CMS_DETACHED is set then cleartext signing will be used, this option only makes sense for SignedData where CMS_DETACHED is also set when CMS_sign() is called. If the CMS_TEXT flag is set MIME headers for type text/plain are added to the content, this only makes sense if CMS_DETACHED is also set. If the CMS_STREAM flag is set streaming is performed. This flag should only be set if CMS_STREAM was also set in the previous call to a CMS_ContentInfo creation function. If cleartext signing is being used and 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 content where the content is absent and DER format is used. BUGS
SMIME_write_CMS() always base64 encodes CMS structures, there should be an option to disable this. RETURN VALUES
SMIME_write_CMS() returns 1 for success or 0 for failure. SEE ALSO
ERR_get_error(3), CMS_sign(3), CMS_verify(3), CMS_encrypt(3) CMS_decrypt(3) HISTORY
SMIME_write_CMS() was added to OpenSSL 0.9.8 1.0.0e 2008-04-10 SMIME_write_CMS(3SSL)
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