=head1 NAME
+EVP_CIPHER_fetch,
EVP_CIPHER_CTX_new,
EVP_CIPHER_CTX_reset,
EVP_CIPHER_CTX_free,
EVP_get_cipherbyname,
EVP_get_cipherbynid,
EVP_get_cipherbyobj,
+EVP_CIPHER_name,
+EVP_CIPHER_provider,
EVP_CIPHER_nid,
EVP_CIPHER_block_size,
EVP_CIPHER_key_length,
EVP_CIPHER_mode,
EVP_CIPHER_type,
EVP_CIPHER_CTX_cipher,
+EVP_CIPHER_CTX_name,
EVP_CIPHER_CTX_nid,
EVP_CIPHER_CTX_block_size,
EVP_CIPHER_CTX_key_length,
EVP_CIPHER_param_to_asn1,
EVP_CIPHER_asn1_to_param,
EVP_CIPHER_CTX_set_padding,
-EVP_enc_null
+EVP_enc_null,
+EVP_CIPHER_do_all_ex
- EVP cipher routines
=head1 SYNOPSIS
#include <openssl/evp.h>
+ EVP_CIPHER *EVP_CIPHER_fetch(OPENSSL_CTX *ctx, const char *algorithm,
+ const char *properties);
EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void);
int EVP_CIPHER_CTX_reset(EVP_CIPHER_CTX *ctx);
void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx);
int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
- ENGINE *impl, unsigned char *key, unsigned char *iv);
+ ENGINE *impl, const unsigned char *key, const unsigned char *iv);
int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out,
int *outl, const unsigned char *in, int inl);
int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl);
int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
- ENGINE *impl, unsigned char *key, unsigned char *iv);
+ ENGINE *impl, const unsigned char *key, const unsigned char *iv);
int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out,
int *outl, const unsigned char *in, int inl);
int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *outm, int *outl);
int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
- ENGINE *impl, unsigned char *key, unsigned char *iv, int enc);
+ ENGINE *impl, const unsigned char *key, const unsigned char *iv, int enc);
int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out,
- int *outl, unsigned char *in, int inl);
+ int *outl, const unsigned char *in, int inl);
int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *outm, int *outl);
int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
- unsigned char *key, unsigned char *iv);
+ const unsigned char *key, const unsigned char *iv);
int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl);
int EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
- unsigned char *key, unsigned char *iv);
+ const unsigned char *key, const unsigned char *iv);
int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *outm, int *outl);
int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
- unsigned char *key, unsigned char *iv, int enc);
+ const unsigned char *key, const unsigned char *iv, int enc);
int EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *outm, int *outl);
int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *x, int padding);
const EVP_CIPHER *EVP_get_cipherbyobj(const ASN1_OBJECT *a);
int EVP_CIPHER_nid(const EVP_CIPHER *e);
+ const char *EVP_CIPHER_name(const EVP_CIPHER *cipher);
+ const OSSL_PROVIDER *EVP_CIPHER_provider(const EVP_CIPHER *cipher);
int EVP_CIPHER_block_size(const EVP_CIPHER *e);
- int EVP_CIPHER_key_length(const EVP_CIPHER *e)
int EVP_CIPHER_key_length(const EVP_CIPHER *e);
int EVP_CIPHER_iv_length(const EVP_CIPHER *e);
unsigned long EVP_CIPHER_flags(const EVP_CIPHER *e);
const EVP_CIPHER *EVP_CIPHER_CTX_cipher(const EVP_CIPHER_CTX *ctx);
int EVP_CIPHER_CTX_nid(const EVP_CIPHER_CTX *ctx);
+ const char *EVP_CIPHER_CTX_name(const EVP_CIPHER_CTX *ctx);
int EVP_CIPHER_CTX_block_size(const EVP_CIPHER_CTX *ctx);
int EVP_CIPHER_CTX_key_length(const EVP_CIPHER_CTX *ctx);
int EVP_CIPHER_CTX_iv_length(const EVP_CIPHER_CTX *ctx);
int EVP_CIPHER_param_to_asn1(EVP_CIPHER_CTX *c, ASN1_TYPE *type);
int EVP_CIPHER_asn1_to_param(EVP_CIPHER_CTX *c, ASN1_TYPE *type);
+ void EVP_CIPHER_do_all_ex(OPENSSL_CTX *libctx,
+ void (*fn)(EVP_CIPHER *cipher, void *arg),
+ void *arg);
+
=head1 DESCRIPTION
The EVP cipher routines are a high level interface to certain
symmetric ciphers.
+EVP_CIPHER_fetch() fetches the cipher implementation for the given
+B<algorithm> from any provider offering it, within the criteria given
+by the B<properties>.
+See L<provider(7)/Fetching algorithms> for further information.
+
+The returned value must eventually be freed with
+L<EVP_CIPHER_meth_free(3)>.
+
EVP_CIPHER_CTX_new() creates a cipher context.
EVP_CIPHER_CTX_free() clears all information from a cipher context
memory.
EVP_EncryptInit_ex() sets up cipher context B<ctx> for encryption
-with cipher B<type> from ENGINE B<impl>. B<ctx> must be created
-before calling this function. B<type> is normally supplied
-by a function such as EVP_aes_256_cbc(). If B<impl> is NULL then the
-default implementation is used. B<key> is the symmetric key to use
+with cipher B<type>. B<type> is typically supplied by a function such
+as EVP_aes_256_cbc(), or a value explicitly fetched with
+EVP_CIPHER_fetch(). If B<impl> is non-NULL, its implementation of the
+cipher B<type> is used if there is one, and if not, the default
+implementation is used. B<key> is the symmetric key to use
and B<iv> is the IV to use (if necessary), the actual number of bytes
used for the key and IV depends on the cipher. It is possible to set
all parameters to NULL except B<type> in an initial call and supply
identifier or does not have ASN1 support this function will return
B<NID_undef>.
+EVP_CIPHER_name() and EVP_CIPHER_CTX_name() return the name of the passed
+cipher or context.
+
+EVP_CIPHER_provider() returns an B<OSSL_PROVIDER> pointer to the provider
+that implements the given B<EVP_CIPHER>.
+
EVP_CIPHER_CTX_cipher() returns the B<EVP_CIPHER> structure when passed
an B<EVP_CIPHER_CTX> structure.
EVP_CIPHER_mode() and EVP_CIPHER_CTX_mode() return the block cipher mode:
EVP_CIPH_ECB_MODE, EVP_CIPH_CBC_MODE, EVP_CIPH_CFB_MODE, EVP_CIPH_OFB_MODE,
EVP_CIPH_CTR_MODE, EVP_CIPH_GCM_MODE, EVP_CIPH_CCM_MODE, EVP_CIPH_XTS_MODE,
-EVP_CIPH_WRAP_MODE or EVP_CIPH_OCB_MODE. If the cipher is a stream cipher then
-EVP_CIPH_STREAM_CIPHER is returned.
+EVP_CIPH_WRAP_MODE, EVP_CIPH_OCB_MODE or EVP_CIPH_SIV_MODE. If the cipher is a
+stream cipher then EVP_CIPH_STREAM_CIPHER is returned.
+
+EVP_CIPHER_flags() returns any flags associated with the cipher. See
+EVP_CIPHER_meth_set_flags() for a list of currently defined flags.
EVP_CIPHER_param_to_asn1() sets the AlgorithmIdentifier "parameter" based
on the passed cipher. This will typically include any parameters and an
generation routine to support keys of a specific form. B<Key> must point to a
buffer at least as big as the value returned by EVP_CIPHER_CTX_key_length().
+EVP_CIPHER_do_all_ex() traverses all ciphers implemented by all activated
+providers in the given library context I<libctx>, and for each of the
+implementations, calls the given function I<fn> with the implementation method
+and the given I<arg> as argument.
+
=head1 RETURN VALUES
+EVP_CIPHER_fetch() returns a pointer to a B<EVP_CIPHER> for success
+and B<NULL> for failure.
+
EVP_CIPHER_CTX_new() returns a pointer to a newly created
B<EVP_CIPHER_CTX> for success and B<NULL> for failure.
EVP_CIPHER_CTX_cipher() returns an B<EVP_CIPHER> structure.
EVP_CIPHER_param_to_asn1() and EVP_CIPHER_asn1_to_param() return greater
-than zero for success and zero or a negative number.
+than zero for success and zero or a negative number on failure.
EVP_CIPHER_CTX_rand_key() returns 1 for success.
This call is made to set the expected B<CCM> tag value when decrypting or
the length of the tag (with the C<tag> parameter set to NULL) when encrypting.
The tag length is often referred to as B<M>. If not set a default value is
-used (12 for AES).
+used (12 for AES). When decrypting, the tag needs to be set before passing
+in data to be decrypted, but as in GCM and OCB mode, it can be set after
+passing additional authenticated data (see L<AEAD Interface>).
=item EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_CCM_SET_L, ivlen, NULL)
=back
+=head2 SIV Mode
+
+For SIV mode ciphers the behaviour of the EVP interface is subtly
+altered and several additional ctrl operations are supported.
+
+To specify any additional authenticated data (AAD) and/or a Nonce, a call to
+EVP_CipherUpdate(), EVP_EncryptUpdate() or EVP_DecryptUpdate() should be made
+with the output parameter B<out> set to B<NULL>.
+
+RFC5297 states that the Nonce is the last piece of AAD before the actual
+encrypt/decrypt takes place. The API does not differentiate the Nonce from
+other AAD.
+
+When decrypting the return value of EVP_DecryptFinal() or EVP_CipherFinal()
+indicates if the operation was successful. If it does not indicate success
+the authentication operation has failed and any output data B<MUST NOT>
+be used as it is corrupted.
+
+The following ctrls are supported in both SIV modes.
+
+=over 4
+
+=item EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_GET_TAG, taglen, tag);
+
+Writes B<taglen> bytes of the tag value to the buffer indicated by B<tag>.
+This call can only be made when encrypting data and B<after> all data has been
+processed (e.g. after an EVP_EncryptFinal() call). For SIV mode the taglen must
+be 16.
+
+=item EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_TAG, taglen, tag);
+
+Sets the expected tag to B<taglen> bytes from B<tag>. This call is only legal
+when decrypting data and must be made B<before> any data is processed (e.g.
+before any EVP_DecryptUpdate() call). For SIV mode the taglen must be 16.
+
+=back
+
+SIV mode makes two passes over the input data, thus, only one call to
+EVP_CipherUpdate(), EVP_EncryptUpdate() or EVP_DecryptUpdate() should be made
+with B<out> set to a non-B<NULL> value. A call to EVP_Decrypt_Final() or
+EVP_CipherFinal() is not required, but will indicate if the update
+operation succeeded.
+
=head2 ChaCha20-Poly1305
The following I<ctrl>s are supported for the ChaCha20-Poly1305 AEAD algorithm.
Sets the nonce length. This call can only be made before specifying the nonce.
If not called a default nonce length of 12 (i.e. 96 bits) is used. The maximum
-nonce length is 16 (B<CHACHA_CTR_SIZE>, i.e. 128-bits).
+nonce length is 12 bytes (i.e. 96-bits). If a nonce of less than 12 bytes is set
+then the nonce is automatically padded with leading 0 bytes to make it 12 bytes
+in length.
=item EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_GET_TAG, taglen, tag)
=head1 HISTORY
-Support for OCB mode was added in OpenSSL 1.1.0
+Support for OCB mode was added in OpenSSL 1.1.0.
B<EVP_CIPHER_CTX> was made opaque in OpenSSL 1.1.0. As a result,
EVP_CIPHER_CTX_reset() appeared and EVP_CIPHER_CTX_cleanup()
=head1 COPYRIGHT
-Copyright 2000-2017 The OpenSSL Project Authors. All Rights Reserved.
+Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved.
-Licensed under the OpenSSL license (the "License"). You may not use
+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>.
projects / openssl.git / blobdiff