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			445 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
			
		
		
	
	
			445 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
=pod
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=head1 NAME
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EVP_PKEY_ASN1_METHOD,
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EVP_PKEY_asn1_new,
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EVP_PKEY_asn1_copy,
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EVP_PKEY_asn1_free,
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EVP_PKEY_asn1_add0,
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EVP_PKEY_asn1_add_alias,
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EVP_PKEY_asn1_set_public,
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EVP_PKEY_asn1_set_private,
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EVP_PKEY_asn1_set_param,
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EVP_PKEY_asn1_set_free,
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EVP_PKEY_asn1_set_ctrl,
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EVP_PKEY_asn1_set_item,
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EVP_PKEY_asn1_set_siginf,
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EVP_PKEY_asn1_set_check,
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EVP_PKEY_asn1_set_public_check,
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EVP_PKEY_asn1_set_param_check,
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EVP_PKEY_asn1_set_security_bits,
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EVP_PKEY_asn1_set_set_priv_key,
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EVP_PKEY_asn1_set_set_pub_key,
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EVP_PKEY_asn1_set_get_priv_key,
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EVP_PKEY_asn1_set_get_pub_key,
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EVP_PKEY_get0_asn1
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- manipulating and registering EVP_PKEY_ASN1_METHOD structure
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=head1 SYNOPSIS
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 #include <openssl/evp.h>
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 typedef struct evp_pkey_asn1_method_st EVP_PKEY_ASN1_METHOD;
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 EVP_PKEY_ASN1_METHOD *EVP_PKEY_asn1_new(int id, int flags,
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                                         const char *pem_str,
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                                         const char *info);
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 void EVP_PKEY_asn1_copy(EVP_PKEY_ASN1_METHOD *dst,
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                         const EVP_PKEY_ASN1_METHOD *src);
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 void EVP_PKEY_asn1_free(EVP_PKEY_ASN1_METHOD *ameth);
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 int EVP_PKEY_asn1_add0(const EVP_PKEY_ASN1_METHOD *ameth);
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 int EVP_PKEY_asn1_add_alias(int to, int from);
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 void EVP_PKEY_asn1_set_public(EVP_PKEY_ASN1_METHOD *ameth,
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                               int (*pub_decode) (EVP_PKEY *pk,
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                                                  const X509_PUBKEY *pub),
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                               int (*pub_encode) (X509_PUBKEY *pub,
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                                                  const EVP_PKEY *pk),
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                               int (*pub_cmp) (const EVP_PKEY *a,
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                                               const EVP_PKEY *b),
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                               int (*pub_print) (BIO *out,
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                                                 const EVP_PKEY *pkey,
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                                                 int indent, ASN1_PCTX *pctx),
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                               int (*pkey_size) (const EVP_PKEY *pk),
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                               int (*pkey_bits) (const EVP_PKEY *pk));
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 void EVP_PKEY_asn1_set_private(EVP_PKEY_ASN1_METHOD *ameth,
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                                int (*priv_decode) (EVP_PKEY *pk,
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                                                    const PKCS8_PRIV_KEY_INFO
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                                                    *p8inf),
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                                int (*priv_encode) (PKCS8_PRIV_KEY_INFO *p8,
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                                                    const EVP_PKEY *pk),
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                                int (*priv_print) (BIO *out,
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                                                   const EVP_PKEY *pkey,
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                                                   int indent,
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                                                   ASN1_PCTX *pctx));
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 void EVP_PKEY_asn1_set_param(EVP_PKEY_ASN1_METHOD *ameth,
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                              int (*param_decode) (EVP_PKEY *pkey,
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                                                   const unsigned char **pder,
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                                                   int derlen),
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                              int (*param_encode) (const EVP_PKEY *pkey,
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                                                   unsigned char **pder),
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                              int (*param_missing) (const EVP_PKEY *pk),
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                              int (*param_copy) (EVP_PKEY *to,
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                                                 const EVP_PKEY *from),
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                              int (*param_cmp) (const EVP_PKEY *a,
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                                                const EVP_PKEY *b),
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                              int (*param_print) (BIO *out,
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                                                  const EVP_PKEY *pkey,
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                                                  int indent,
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                                                  ASN1_PCTX *pctx));
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 void EVP_PKEY_asn1_set_free(EVP_PKEY_ASN1_METHOD *ameth,
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                             void (*pkey_free) (EVP_PKEY *pkey));
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 void EVP_PKEY_asn1_set_ctrl(EVP_PKEY_ASN1_METHOD *ameth,
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                             int (*pkey_ctrl) (EVP_PKEY *pkey, int op,
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                                               long arg1, void *arg2));
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 void EVP_PKEY_asn1_set_item(EVP_PKEY_ASN1_METHOD *ameth,
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                             int (*item_verify) (EVP_MD_CTX *ctx,
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                                                 const ASN1_ITEM *it,
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                                                 void *asn,
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                                                 X509_ALGOR *a,
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                                                 ASN1_BIT_STRING *sig,
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                                                 EVP_PKEY *pkey),
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                             int (*item_sign) (EVP_MD_CTX *ctx,
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                                               const ASN1_ITEM *it,
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                                               void *asn,
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                                               X509_ALGOR *alg1,
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                                               X509_ALGOR *alg2,
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                                               ASN1_BIT_STRING *sig));
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 void EVP_PKEY_asn1_set_siginf(EVP_PKEY_ASN1_METHOD *ameth,
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                               int (*siginf_set) (X509_SIG_INFO *siginf,
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                                                  const X509_ALGOR *alg,
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                                                  const ASN1_STRING *sig));
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 void EVP_PKEY_asn1_set_check(EVP_PKEY_ASN1_METHOD *ameth,
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                              int (*pkey_check) (const EVP_PKEY *pk));
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 void EVP_PKEY_asn1_set_public_check(EVP_PKEY_ASN1_METHOD *ameth,
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                                     int (*pkey_pub_check) (const EVP_PKEY *pk));
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 void EVP_PKEY_asn1_set_param_check(EVP_PKEY_ASN1_METHOD *ameth,
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                                    int (*pkey_param_check) (const EVP_PKEY *pk));
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 void EVP_PKEY_asn1_set_security_bits(EVP_PKEY_ASN1_METHOD *ameth,
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                                      int (*pkey_security_bits) (const EVP_PKEY
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                                                                 *pk));
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 void EVP_PKEY_asn1_set_set_priv_key(EVP_PKEY_ASN1_METHOD *ameth,
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                                     int (*set_priv_key) (EVP_PKEY *pk,
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                                                          const unsigned char
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                                                             *priv,
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                                                          size_t len));
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 void EVP_PKEY_asn1_set_set_pub_key(EVP_PKEY_ASN1_METHOD *ameth,
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                                    int (*set_pub_key) (EVP_PKEY *pk,
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                                                        const unsigned char *pub,
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                                                        size_t len));
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 void EVP_PKEY_asn1_set_get_priv_key(EVP_PKEY_ASN1_METHOD *ameth,
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                                     int (*get_priv_key) (const EVP_PKEY *pk,
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                                                          unsigned char *priv,
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                                                          size_t *len));
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 void EVP_PKEY_asn1_set_get_pub_key(EVP_PKEY_ASN1_METHOD *ameth,
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                                    int (*get_pub_key) (const EVP_PKEY *pk,
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                                                        unsigned char *pub,
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                                                        size_t *len));
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 const EVP_PKEY_ASN1_METHOD *EVP_PKEY_get0_asn1(const EVP_PKEY *pkey);
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=head1 DESCRIPTION
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B<EVP_PKEY_ASN1_METHOD> is a structure which holds a set of ASN.1
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conversion, printing and information methods for a specific public key
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algorithm.
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There are two places where the B<EVP_PKEY_ASN1_METHOD> objects are
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stored: one is a built-in array representing the standard methods for
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different algorithms, and the other one is a stack of user-defined
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application-specific methods, which can be manipulated by using
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L<EVP_PKEY_asn1_add0(3)>.
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=head2 Methods
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The methods are the underlying implementations of a particular public
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key algorithm present by the B<EVP_PKEY> object.
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 int (*pub_decode) (EVP_PKEY *pk, X509_PUBKEY *pub);
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 int (*pub_encode) (X509_PUBKEY *pub, const EVP_PKEY *pk);
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 int (*pub_cmp) (const EVP_PKEY *a, const EVP_PKEY *b);
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 int (*pub_print) (BIO *out, const EVP_PKEY *pkey, int indent,
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                   ASN1_PCTX *pctx);
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The pub_decode() and pub_encode() methods are called to decode /
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encode B<X509_PUBKEY> ASN.1 parameters to / from B<pk>.
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They MUST return 0 on error, 1 on success.
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They're called by L<X509_PUBKEY_get0(3)> and L<X509_PUBKEY_set(3)>.
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The pub_cmp() method is called when two public keys are to be
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compared.
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It MUST return 1 when the keys are equal, 0 otherwise.
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It's called by L<EVP_PKEY_eq(3)>.
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The pub_print() method is called to print a public key in humanly
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readable text to B<out>, indented B<indent> spaces.
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It MUST return 0 on error, 1 on success.
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It's called by L<EVP_PKEY_print_public(3)>.
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 int (*priv_decode) (EVP_PKEY *pk, const PKCS8_PRIV_KEY_INFO *p8inf);
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 int (*priv_encode) (PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pk);
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 int (*priv_print) (BIO *out, const EVP_PKEY *pkey, int indent,
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                    ASN1_PCTX *pctx);
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The priv_decode() and priv_encode() methods are called to decode /
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encode B<PKCS8_PRIV_KEY_INFO> form private key to / from B<pk>.
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They MUST return 0 on error, 1 on success.
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They're called by L<EVP_PKCS82PKEY(3)> and L<EVP_PKEY2PKCS8(3)>.
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The priv_print() method is called to print a private key in humanly
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readable text to B<out>, indented B<indent> spaces.
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It MUST return 0 on error, 1 on success.
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It's called by L<EVP_PKEY_print_private(3)>.
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 int (*pkey_size) (const EVP_PKEY *pk);
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 int (*pkey_bits) (const EVP_PKEY *pk);
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 int (*pkey_security_bits) (const EVP_PKEY *pk);
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The pkey_size() method returns the key size in bytes.
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It's called by L<EVP_PKEY_size(3)>.
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The pkey_bits() method returns the key size in bits.
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It's called by L<EVP_PKEY_bits(3)>.
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 int (*param_decode) (EVP_PKEY *pkey,
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                      const unsigned char **pder, int derlen);
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 int (*param_encode) (const EVP_PKEY *pkey, unsigned char **pder);
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 int (*param_missing) (const EVP_PKEY *pk);
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 int (*param_copy) (EVP_PKEY *to, const EVP_PKEY *from);
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 int (*param_cmp) (const EVP_PKEY *a, const EVP_PKEY *b);
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 int (*param_print) (BIO *out, const EVP_PKEY *pkey, int indent,
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                     ASN1_PCTX *pctx);
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The param_decode() and param_encode() methods are called to decode /
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encode DER formatted parameters to / from B<pk>.
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They MUST return 0 on error, 1 on success.
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They're called by L<PEM_read_bio_Parameters(3)> and the B<file:>
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L<OSSL_STORE_LOADER(3)>.
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The param_missing() method returns 0 if a key parameter is missing,
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otherwise 1.
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It's called by L<EVP_PKEY_missing_parameters(3)>.
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The param_copy() method copies key parameters from B<from> to B<to>.
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It MUST return 0 on error, 1 on success.
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It's called by L<EVP_PKEY_copy_parameters(3)>.
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The param_cmp() method compares the parameters of keys B<a> and B<b>.
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It MUST return 1 when the keys are equal, 0 when not equal, or a
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negative number on error.
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It's called by L<EVP_PKEY_parameters_eq(3)>.
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The param_print() method prints the private key parameters in humanly
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readable text to B<out>, indented B<indent> spaces.
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It MUST return 0 on error, 1 on success.
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It's called by L<EVP_PKEY_print_params(3)>.
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 int (*sig_print) (BIO *out,
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                   const X509_ALGOR *sigalg, const ASN1_STRING *sig,
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                   int indent, ASN1_PCTX *pctx);
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The sig_print() method prints a signature in humanly readable text to
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B<out>, indented B<indent> spaces.
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B<sigalg> contains the exact signature algorithm.
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If the signature in B<sig> doesn't correspond to what this method
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expects, X509_signature_dump() must be used as a last resort.
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It MUST return 0 on error, 1 on success.
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It's called by L<X509_signature_print(3)>.
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 void (*pkey_free) (EVP_PKEY *pkey);
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The pkey_free() method helps freeing the internals of B<pkey>.
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It's called by L<EVP_PKEY_free(3)>, L<EVP_PKEY_set_type(3)>,
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L<EVP_PKEY_set_type_str(3)>, and L<EVP_PKEY_assign(3)>.
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 int (*pkey_ctrl) (EVP_PKEY *pkey, int op, long arg1, void *arg2);
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The pkey_ctrl() method adds extra algorithm specific control.
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It's called by L<EVP_PKEY_get_default_digest_nid(3)>,
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L<EVP_PKEY_supports_digest_nid(3)>,
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L<EVP_PKEY_set1_tls_encodedpoint(3)>,
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L<EVP_PKEY_get1_tls_encodedpoint(3)>, L<PKCS7_SIGNER_INFO_set(3)>,
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L<PKCS7_RECIP_INFO_set(3)>, ...
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 int (*old_priv_decode) (EVP_PKEY *pkey,
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                         const unsigned char **pder, int derlen);
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 int (*old_priv_encode) (const EVP_PKEY *pkey, unsigned char **pder);
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The old_priv_decode() and old_priv_encode() methods decode / encode
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they private key B<pkey> from / to a DER formatted array.
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These are exclusively used to help decoding / encoding older (pre
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PKCS#8) PEM formatted encrypted private keys.
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old_priv_decode() MUST return 0 on error, 1 on success.
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old_priv_encode() MUST the return same kind of values as
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i2d_PrivateKey().
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They're called by L<d2i_PrivateKey(3)> and L<i2d_PrivateKey(3)>.
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 int (*item_verify) (EVP_MD_CTX *ctx, const ASN1_ITEM *it, void *asn,
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                     X509_ALGOR *a, ASN1_BIT_STRING *sig, EVP_PKEY *pkey);
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 int (*item_sign) (EVP_MD_CTX *ctx, const ASN1_ITEM *it, void *asn,
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                   X509_ALGOR *alg1, X509_ALGOR *alg2,
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                   ASN1_BIT_STRING *sig);
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The item_sign() and  item_verify() methods make it possible to have
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algorithm specific signatures and verification of them.
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item_sign() MUST return one of:
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=over 4
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=item <=0
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error
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=item Z<>1
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item_sign() did everything, OpenSSL internals just needs to pass the
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signature length back.
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=item Z<>2
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item_sign() did nothing, OpenSSL internal standard routines are
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expected to continue with the default signature production.
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=item Z<>3
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item_sign() set the algorithm identifier B<algor1> and B<algor2>,
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OpenSSL internals should just sign using those algorithms.
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=back
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item_verify() MUST return one of:
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=over 4
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=item <=0
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error
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=item Z<>1
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item_sign() did everything, OpenSSL internals just needs to pass the
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signature length back.
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=item Z<>2
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item_sign() did nothing, OpenSSL internal standard routines are
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expected to continue with the default signature production.
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=back
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item_verify() and item_sign() are called by L<ASN1_item_verify(3)> and
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L<ASN1_item_sign(3)>, and by extension, L<X509_verify(3)>,
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L<X509_REQ_verify(3)>, L<X509_sign(3)>, L<X509_REQ_sign(3)>, ...
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 int (*siginf_set) (X509_SIG_INFO *siginf, const X509_ALGOR *alg,
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                    const ASN1_STRING *sig);
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The siginf_set() method is used to set custom B<X509_SIG_INFO>
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parameters.
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It MUST return 0 on error, or 1 on success.
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It's called as part of L<X509_check_purpose(3)>, L<X509_check_ca(3)>
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and L<X509_check_issued(3)>.
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 int (*pkey_check) (const EVP_PKEY *pk);
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 int (*pkey_public_check) (const EVP_PKEY *pk);
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 int (*pkey_param_check) (const EVP_PKEY *pk);
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The pkey_check(), pkey_public_check() and pkey_param_check() methods are used
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to check the validity of B<pk> for key-pair, public component and parameters,
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respectively.
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They MUST return 0 for an invalid key, or 1 for a valid key.
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They are called by L<EVP_PKEY_check(3)>, L<EVP_PKEY_public_check(3)> and
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L<EVP_PKEY_param_check(3)> respectively.
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 int (*set_priv_key) (EVP_PKEY *pk, const unsigned char *priv, size_t len);
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 int (*set_pub_key) (EVP_PKEY *pk, const unsigned char *pub, size_t len);
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The set_priv_key() and set_pub_key() methods are used to set the raw private and
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public key data for an EVP_PKEY. They MUST return 0 on error, or 1 on success.
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They are called by L<EVP_PKEY_new_raw_private_key(3)>, and
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L<EVP_PKEY_new_raw_public_key(3)> respectively.
 | 
						|
 | 
						|
 size_t (*dirty) (const EVP_PKEY *pk);
 | 
						|
 void *(*export_to) (const EVP_PKEY *pk, EVP_KEYMGMT *keymgmt);
 | 
						|
 | 
						|
dirty_cnt() returns the internal key's dirty count.
 | 
						|
This can be used to synchronise different copies of the same keys.
 | 
						|
 | 
						|
The export_to() method exports the key material from the given key to
 | 
						|
a provider, through the L<EVP_KEYMGMT(3)> interface, if that provider
 | 
						|
supports importing key material.
 | 
						|
 | 
						|
=head2 Functions
 | 
						|
 | 
						|
EVP_PKEY_asn1_new() creates and returns a new B<EVP_PKEY_ASN1_METHOD>
 | 
						|
object, and associates the given B<id>, B<flags>, B<pem_str> and
 | 
						|
B<info>.
 | 
						|
B<id> is a NID, B<pem_str> is the PEM type string, B<info> is a
 | 
						|
descriptive string.
 | 
						|
The following B<flags> are supported:
 | 
						|
 | 
						|
 ASN1_PKEY_SIGPARAM_NULL
 | 
						|
 | 
						|
If B<ASN1_PKEY_SIGPARAM_NULL> is set, then the signature algorithm
 | 
						|
parameters are given the type B<V_ASN1_NULL> by default, otherwise
 | 
						|
they will be given the type B<V_ASN1_UNDEF> (i.e. the parameter is
 | 
						|
omitted).
 | 
						|
See L<X509_ALGOR_set0(3)> for more information.
 | 
						|
 | 
						|
EVP_PKEY_asn1_copy() copies an B<EVP_PKEY_ASN1_METHOD> object from
 | 
						|
B<src> to B<dst>.
 | 
						|
This function is not thread safe, it's recommended to only use this
 | 
						|
when initializing the application.
 | 
						|
 | 
						|
EVP_PKEY_asn1_free() frees an existing B<EVP_PKEY_ASN1_METHOD> pointed
 | 
						|
by B<ameth>.
 | 
						|
 | 
						|
EVP_PKEY_asn1_add0() adds B<ameth> to the user defined stack of
 | 
						|
methods unless another B<EVP_PKEY_ASN1_METHOD> with the same NID is
 | 
						|
already there.
 | 
						|
This function is not thread safe, it's recommended to only use this
 | 
						|
when initializing the application.
 | 
						|
 | 
						|
EVP_PKEY_asn1_add_alias() creates an alias with the NID B<to> for the
 | 
						|
B<EVP_PKEY_ASN1_METHOD> with NID B<from> unless another
 | 
						|
B<EVP_PKEY_ASN1_METHOD> with the same NID is already added.
 | 
						|
This function is not thread safe, it's recommended to only use this
 | 
						|
when initializing the application.
 | 
						|
 | 
						|
EVP_PKEY_asn1_set_public(), EVP_PKEY_asn1_set_private(),
 | 
						|
EVP_PKEY_asn1_set_param(), EVP_PKEY_asn1_set_free(),
 | 
						|
EVP_PKEY_asn1_set_ctrl(), EVP_PKEY_asn1_set_item(),
 | 
						|
EVP_PKEY_asn1_set_siginf(), EVP_PKEY_asn1_set_check(),
 | 
						|
EVP_PKEY_asn1_set_public_check(), EVP_PKEY_asn1_set_param_check(),
 | 
						|
EVP_PKEY_asn1_set_security_bits(), EVP_PKEY_asn1_set_set_priv_key(),
 | 
						|
EVP_PKEY_asn1_set_set_pub_key(), EVP_PKEY_asn1_set_get_priv_key() and
 | 
						|
EVP_PKEY_asn1_set_get_pub_key() set the diverse methods of the given
 | 
						|
B<EVP_PKEY_ASN1_METHOD> object.
 | 
						|
 | 
						|
EVP_PKEY_get0_asn1() finds the B<EVP_PKEY_ASN1_METHOD> associated
 | 
						|
with the key B<pkey>.
 | 
						|
 | 
						|
=head1 RETURN VALUES
 | 
						|
 | 
						|
EVP_PKEY_asn1_new() returns NULL on error, or a pointer to an
 | 
						|
B<EVP_PKEY_ASN1_METHOD> object otherwise.
 | 
						|
 | 
						|
EVP_PKEY_asn1_add0() and EVP_PKEY_asn1_add_alias() return 0 on error,
 | 
						|
or 1 on success.
 | 
						|
 | 
						|
EVP_PKEY_get0_asn1() returns NULL on error, or a pointer to a constant
 | 
						|
B<EVP_PKEY_ASN1_METHOD> object otherwise.
 | 
						|
 | 
						|
=head1 COPYRIGHT
 | 
						|
 | 
						|
Copyright 2017-2020 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
 | 
						|
L<https://www.openssl.org/source/license.html>.
 | 
						|
 | 
						|
=cut
 |