More docs.

=pod

=head1 NAME

EVP_PKEY_new, EVP_PKEY_free - private key allocation functions.

=head1 SYNOPSIS

 #include <openssl/evp.h>

 EVP_PKEY *EVP_PKEY_new(void);

 void EVP_PKEY_free(EVP_PKEY *key);

=head1 DESCRIPTION

The EVP_PKEY_new() function allocates an empty B<EVP_PKEY> 

structure which is used by OpenSSL to store private keys.

EVP_PKEY_free() frees up the private key B<key>.

=head1 NOTES

The B<EVP_PKEY> structure is used by various OpenSSL functions

which require a general private key without reference to any

particular algorithm.

The structure returned by EVP_PKEY_new() is empty. To add a

private key to this empty structure the functions described in

L<EVP_PKEY_set1_RSA(3)|EVP_PKEY_set1_RSA(3)> should be used.

=head1 RETURN VALUES

EVP_PKEY_new() returns either the newly allocated B<EVP_PKEY>

structure of B<NULL> if an error occurred.

EVP_PKEY_free() does not return a value.

=head1 SEE ALSO

L<EVP_PKEY_set1_RSA(3)|EVP_PKEY_set1_RSA(3)>

=head1 HISTORY

TBA

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=pod

=head1 NAME

EVP_PKEY_set1_RSA, EVP_PKEY_set1_DSA, EVP_PKEY_set1_DH, EVP_PKEY_set1_EC_KEY,

EVP_PKEY_get1_RSA, EVP_PKEY_get1_DSA, EVP_PKEY_get1_DH, EVP_PKEY_get1_EC_KEY,

EVP_PKEY_assign_RSA, EVP_PKEY_assign_DSA, EVP_PKEY_assign_DH, EVP_PKEY_assign_EC_KEY,

EVP_PKEY_type - EVP_PKEY assignment functions.

=head1 SYNOPSIS

 #include <openssl/evp.h>

 int EVP_PKEY_set1_RSA(EVP_PKEY *pkey,RSA *key);

 int EVP_PKEY_set1_DSA(EVP_PKEY *pkey,DSA *key);

 int EVP_PKEY_set1_DH(EVP_PKEY *pkey,DH *key);

 int EVP_PKEY_set1_EC_KEY(EVP_PKEY *pkey,EC_KEY *key);

 RSA *EVP_PKEY_get1_RSA(EVP_PKEY *pkey);

 DSA *EVP_PKEY_get1_DSA(EVP_PKEY *pkey);

 DH *EVP_PKEY_get1_DH(EVP_PKEY *pkey);

 EC_KEY *EVP_PKEY_get1_EC_KEY(EVP_PKEY *pkey);

 int EVP_PKEY_assign_RSA(EVP_PKEY *pkey,RSA *key);

 int EVP_PKEY_assign_DSA(EVP_PKEY *pkey,DSA *key);

 int EVP_PKEY_assign_DH(EVP_PKEY *pkey,DH *key);

 int EVP_PKEY_assign_EC_KEY(EVP_PKEY *pkey,EC_KEY *key);

 int EVP_PKEY_type(int type);

=head1 DESCRIPTION

EVP_PKEY_set1_RSA(), EVP_PKEY_set1_DSA(), EVP_PKEY_set1_DH() and

EVP_PKEY_set1_EC_KEY() set the key referenced by B<pkey> to B<key>.

EVP_PKEY_get1_RSA(), EVP_PKEY_get1_DSA(), EVP_PKEY_get1_DH() and

EVP_PKEY_get1_EC_KEY() return the referenced key in B<pkey> or

B<NULL> if the key is not of the correct type.

EVP_PKEY_assign_RSA() EVP_PKEY_assign_DSA(), EVP_PKEY_assign_DH()

and EVP_PKEY_assign_EC_KEY() also set the referenced key to B<key>

however these use the supplied B<key> internally and so B<key>

will be freed when the parent B<pkey> is freed.

EVP_PKEY_type() returns the type of key corresponding to the value

B<type>. The type of a key can be obtained with

EVP_PKEY_type(pkey->type). The return value will be EVP_PKEY_RSA,

EVP_PKEY_DSA, EVP_PKEY_DH or EVP_PKEY_EC for the corresponding

key types or NID_undef if the key type is unassigned.

=head1 NOTES

In accordance with the OpenSSL naming convention the key obtained

from or assigned to the B<pkey> using the B<1> functions must be

freed as well as B<pkey>.

EVP_PKEY_assign_RSA() EVP_PKEY_assign_DSA(), EVP_PKEY_assign_DH()

EVP_PKEY_assign_EC_KEY() are implemented as macros.

=head1 RETURN VALUES

EVP_PKEY_set1_RSA(), EVP_PKEY_set1_DSA(), EVP_PKEY_set1_DH() and

EVP_PKEY_set1_EC_KEY() return 1 for success or 0 for failure.

EVP_PKEY_get1_RSA(), EVP_PKEY_get1_DSA(), EVP_PKEY_get1_DH() and

EVP_PKEY_get1_EC_KEY() return the referenced key or B<NULL> if 

an error occurred.

EVP_PKEY_assign_RSA() EVP_PKEY_assign_DSA(), EVP_PKEY_assign_DH()

and EVP_PKEY_assign_EC_KEY() return 1 for success and 0 for failure.

=head1 SEE ALSO

L<EVP_PKEY_new(3)|EVP_PKEY_new(3)>

=head1 HISTORY

TBA

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=pod

=head1 NAME

PKCS7_sign - create a PKCS#7 signedData structure

=head1 SYNOPSIS

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

=head1 DESCRIPTION

PKCS7_sign() creates and returns a PKCS#7 signedData structure. B<signcert>

is the certificate to sign with, B<pkey> is the corresponsding private key.

B<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 B<data>.

B<flags> is an optional set of flags.

=head1 NOTES

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

Many S/MIME clients expect the signed content to include valid MIME headers. If

the B<PKCS7_TEXT> flag is set MIME headers for type B<text/plain> are prepended

to the data.

If B<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 B<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 B<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 B<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 B<PKCS7_NOATTR> is set then no authenticatedAttributes

will be used. If B<PKCS7_NOSMIMECAP> is set then just the SMIMECapabilities are

omitted.

=head1 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).

=head1 SEE ALSO

L<ERR_get_error(3)|ERR_get_error(3)>, L<PKCS7_verify(3)|PKCS7_verify(3)>

=head1 HISTORY

TBA

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