=head1 NAME
EVP_CIPHER_fetch,
+EVP_CIPHER_up_ref,
+EVP_CIPHER_free,
EVP_CIPHER_CTX_new,
EVP_CIPHER_CTX_reset,
EVP_CIPHER_CTX_free,
EVP_DecryptFinal,
EVP_CipherInit,
EVP_CipherFinal,
+EVP_Cipher,
EVP_get_cipherbyname,
EVP_get_cipherbynid,
EVP_get_cipherbyobj,
+EVP_CIPHER_is_a,
EVP_CIPHER_name,
+EVP_CIPHER_number,
+EVP_CIPHER_names_do_all,
EVP_CIPHER_provider,
EVP_CIPHER_nid,
EVP_CIPHER_get_params,
EVP_CIPHER_CTX_name,
EVP_CIPHER_CTX_nid,
EVP_CIPHER_CTX_get_params,
-EVP_CIPHER_CTX_gettable_params,
+EVP_CIPHER_gettable_ctx_params,
EVP_CIPHER_CTX_set_params,
-EVP_CIPHER_CTX_settable_params,
+EVP_CIPHER_settable_ctx_params,
EVP_CIPHER_CTX_block_size,
EVP_CIPHER_CTX_key_length,
EVP_CIPHER_CTX_iv_length,
+EVP_CIPHER_CTX_tag_length,
EVP_CIPHER_CTX_get_app_data,
EVP_CIPHER_CTX_set_app_data,
EVP_CIPHER_CTX_type,
EVP_CIPHER_asn1_to_param,
EVP_CIPHER_CTX_set_padding,
EVP_enc_null,
-EVP_CIPHER_do_all_ex
+EVP_CIPHER_do_all_provided
- EVP cipher routines
=head1 SYNOPSIS
-=for comment generic
+=for openssl generic
#include <openssl/evp.h>
EVP_CIPHER *EVP_CIPHER_fetch(OPENSSL_CTX *ctx, const char *algorithm,
const char *properties);
+ int EVP_CIPHER_up_ref(EVP_CIPHER *cipher);
+ void EVP_CIPHER_free(EVP_CIPHER *cipher);
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);
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(EVP_CIPHER_CTX *ctx, unsigned char *out,
+ const unsigned char *in, unsigned int inl);
+
int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *x, int padding);
int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *x, int keylen);
int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr);
const EVP_CIPHER *EVP_get_cipherbyobj(const ASN1_OBJECT *a);
int EVP_CIPHER_nid(const EVP_CIPHER *e);
+ int EVP_CIPHER_number(const EVP_CIPHER *e);
+ int EVP_CIPHER_is_a(const EVP_CIPHER *cipher, const char *name);
+ void EVP_CIPHER_names_do_all(const EVP_CIPHER *cipher,
+ void (*fn)(const char *name, void *data),
+ void *data);
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_CTX_set_params(EVP_CIPHER_CTX *ctx, const OSSL_PARAM params[]);
int EVP_CIPHER_CTX_get_params(EVP_CIPHER_CTX *ctx, OSSL_PARAM params[]);
const OSSL_PARAM *EVP_CIPHER_gettable_params(const EVP_CIPHER *cipher);
- const OSSL_PARAM *EVP_CIPHER_CTX_settable_params(const EVP_CIPHER *cipher);
- const OSSL_PARAM *EVP_CIPHER_CTX_gettable_params(const EVP_CIPHER *cipher);
+ const OSSL_PARAM *EVP_CIPHER_settable_ctx_params(const EVP_CIPHER *cipher);
+ const OSSL_PARAM *EVP_CIPHER_gettable_ctx_params(const EVP_CIPHER *cipher);
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_CTX_tag_length(const EVP_CIPHER_CTX *ctx);
void *EVP_CIPHER_CTX_get_app_data(const EVP_CIPHER_CTX *ctx);
void EVP_CIPHER_CTX_set_app_data(const EVP_CIPHER_CTX *ctx, void *data);
int EVP_CIPHER_CTX_type(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);
+ void EVP_CIPHER_do_all_provided(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
+The EVP cipher routines are a high-level interface to certain
symmetric ciphers.
+The B<EVP_CIPHER> type is a structure for cipher method implementation.
+
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)>.
+The returned value must eventually be freed with EVP_CIPHER_free().
+
+EVP_CIPHER_up_ref() increments the reference count for an B<EVP_CIPHER>
+structure.
+
+EVP_CIPHER_free() decrements the reference count for the B<EVP_CIPHER>
+structure.
+If the reference count drops to 0 then the structure is freed.
EVP_CIPHER_CTX_new() creates a cipher context.
EVP_EncryptUpdate() encrypts B<inl> bytes from the buffer B<in> and
writes the encrypted version to B<out>. This function can be called
multiple times to encrypt successive blocks of data. The amount
-of data written depends on the block alignment of the encrypted data:
-as a result the amount of data written may be anything from zero bytes
-to (inl + cipher_block_size - 1) so B<out> should contain sufficient
-room. The actual number of bytes written is placed in B<outl>. It also
+of data written depends on the block alignment of the encrypted data.
+For most ciphers and modes, the amount of data written can be anything
+from zero bytes to (inl + cipher_block_size - 1) bytes.
+For wrap cipher modes, the amount of data written can be anything
+from zero bytes to (inl + cipher_block_size) bytes.
+For stream ciphers, the amount of data written can be anything from zero
+bytes to inl bytes.
+Thus, B<out> should contain sufficient room for the operation being performed.
+The actual number of bytes written is placed in B<outl>. It also
checks if B<in> and B<out> are partially overlapping, and if they are
0 is returned to indicate failure.
the B<ctx>, but this is no longer done and EVP_CIPHER_CTX_clean()
must be called to free any context resources.
+EVP_Cipher() encrypts or decrypts a maximum I<inl> amount of bytes from
+I<in> and leaves the result in I<out>.
+If the cipher doesn't have the flag B<EVP_CIPH_FLAG_CUSTOM_CIPHER> set,
+then I<inl> must be a multiple of EVP_CIPHER_block_size(). If it isn't,
+the result is undefined. If the cipher has that flag set, then I<inl>
+can be any size.
+This function is historic and shouldn't be used in an application, please
+consider using EVP_CipherUpdate() and EVP_CipherFinal_ex instead.
+
EVP_get_cipherbyname(), EVP_get_cipherbynid() and EVP_get_cipherbyobj()
return an EVP_CIPHER structure when passed a cipher name, a NID or an
ASN1_OBJECT structure.
EVP_CIPHER_CTX_get_params() retrieves the requested list of operation
B<params> from CIPHER context B<ctx>.
-EVP_CIPHER_gettable_params(), EVP_CIPHER_CTX_gettable_params(), and
-EVP_CIPHER_CTX_settable_params() get a constant B<OSSL_PARAM> array
-that decribes the retrievable and settable parameters, i.e. parameters
+EVP_CIPHER_gettable_params(), EVP_CIPHER_gettable_ctx_params(), and
+EVP_CIPHER_settable_ctx_params() get a constant B<OSSL_PARAM> array
+that describes the retrievable and settable parameters, i.e. parameters
that can be used with EVP_CIPHER_get_params(), EVP_CIPHER_CTX_get_params()
and EVP_CIPHER_CTX_set_params(), respectively.
See L<OSSL_PARAM(3)> for the use of B<OSSL_PARAM> as parameter descriptor.
It will return zero if the cipher does not use an IV. The constant
B<EVP_MAX_IV_LENGTH> is the maximum IV length for all ciphers.
+EVP_CIPHER_CTX_tag_length() returns the tag length of a AEAD cipher when passed
+a B<EVP_CIPHER_CTX>. It will return zero if the cipher does not support a tag.
+It returns a default value if the tag length has not been set.
+
EVP_CIPHER_block_size() and EVP_CIPHER_CTX_block_size() return the block
size of a cipher when passed an B<EVP_CIPHER> or B<EVP_CIPHER_CTX>
structure. The constant B<EVP_MAX_BLOCK_LENGTH> is also the maximum block
identifier or does not have ASN1 support this function will return
B<NID_undef>.
+EVP_CIPHER_is_a() returns 1 if I<cipher> is an implementation of an
+algorithm that's identifiable with I<name>, otherwise 0.
+If I<cipher> is a legacy cipher (it's the return value from the likes
+of EVP_aes128() rather than the result of an EVP_CIPHER_fetch()), only
+cipher names registered with the default library context (see
+L<OPENSSL_CTX(3)>) will be considered.
+
+EVP_CIPHER_number() returns the internal dynamic number assigned to
+the I<cipher>. This is only useful with fetched B<EVP_CIPHER>s.
+
EVP_CIPHER_name() and EVP_CIPHER_CTX_name() return the name of the passed
-cipher or context.
+cipher or context. For fetched ciphers with multiple names, only one
+of them is returned; it's recommended to use EVP_CIPHER_names_do_all()
+instead.
+
+EVP_CIPHER_names_do_all() traverses all names for the I<cipher>, and
+calls I<fn> with each name and I<data>. This is only useful with
+fetched B<EVP_CIPHER>s.
EVP_CIPHER_provider() returns an B<OSSL_PROVIDER> pointer to the provider
that implements the given B<EVP_CIPHER>.
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
+EVP_CIPHER_do_all_provided() 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.
EVP_CIPHER_fetch() returns a pointer to a B<EVP_CIPHER> for success
and B<NULL> for failure.
+EVP_CIPHER_up_ref() returns 1 for success or 0 otherwise.
+
EVP_CIPHER_CTX_new() returns a pointer to a newly created
B<EVP_CIPHER_CTX> for success and B<NULL> for failure.
EVP_CipherInit_ex() and EVP_CipherUpdate() return 1 for success and 0 for failure.
EVP_CipherFinal_ex() returns 0 for a decryption failure or 1 for success.
+EVP_Cipher() returns the amount of encrypted / decrypted bytes, or -1
+on failure, if the flag B<EVP_CIPH_FLAG_CUSTOM_CIPHER> is set for the
+cipher. EVP_Cipher() returns 1 on success or 0 on failure, if the flag
+B<EVP_CIPH_FLAG_CUSTOM_CIPHER> is not set for the cipher.
+
EVP_CIPHER_CTX_reset() returns 1 for success and 0 for failure.
EVP_get_cipherbyname(), EVP_get_cipherbynid() and EVP_get_cipherbyobj()
EVP_CIPHER_iv_length() and EVP_CIPHER_CTX_iv_length() return the IV
length or zero if the cipher does not use an IV.
+EVP_CIPHER_CTX_tag_length() return the tag length or zero if the cipher does not
+use a tag.
+
EVP_CIPHER_type() and EVP_CIPHER_CTX_type() return the NID of the cipher's
OBJECT IDENTIFIER or NID_undef if it has no defined OBJECT IDENTIFIER.
All algorithms have a fixed key length unless otherwise stated.
-Refer to L<SEE ALSO> for the full list of ciphers available through the EVP
+Refer to L</SEE ALSO> for the full list of ciphers available through the EVP
interface.
=over 4
=item EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_IVLEN, ivlen, NULL)
-Sets the CCM nonce (IV) length. This call can only be made before specifying an
+Sets the CCM nonce (IV) length. This call can only be made before specifying a
nonce value. The nonce length is given by B<15 - L> so it is 7 by default for
AES.
=head1 NOTES
Where possible the B<EVP> interface to symmetric ciphers should be used in
-preference to the low level interfaces. This is because the code then becomes
+preference to the low-level interfaces. This is because the code then becomes
transparent to the cipher used and much more flexible. Additionally, the
B<EVP> interface will ensure the use of platform specific cryptographic
-acceleration such as AES-NI (the low level interfaces do not provide the
+acceleration such as AES-NI (the low-level interfaces do not provide the
guarantee).
PKCS padding works by adding B<n> padding bytes of value B<n> to make the total
EVP_CipherInit_ex() and EVP_CipherFinal_ex() because they can reuse an
existing context without allocating and freeing it up on each call.
+There are some differences between functions EVP_CipherInit() and
+EVP_CipherInit_ex(), significant in some circumstances. EVP_CipherInit() fills
+the passed context object with zeros. As a consequence, EVP_CipherInit() does
+not allow step-by-step initialization of the ctx when the I<key> and I<iv> are
+passed in separate calls. It also means that the flags set for the CTX are
+removed, and it is especially important for the
+B<EVP_CIPHER_CTX_FLAG_WRAP_ALLOW> flag treated specially in
+EVP_CipherInit_ex().
+
EVP_get_cipherbynid(), and EVP_get_cipherbyobj() are implemented as macros.
=head1 BUGS
/* Don't set key or IV right away; we want to check lengths */
ctx = EVP_CIPHER_CTX_new();
- EVP_CipherInit_ex(&ctx, EVP_aes_128_cbc(), NULL, NULL, NULL,
+ EVP_CipherInit_ex(ctx, EVP_aes_128_cbc(), NULL, NULL, NULL,
do_encrypt);
OPENSSL_assert(EVP_CIPHER_CTX_key_length(ctx) == 16);
OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) == 16);
return 1;
}
+Encryption using AES-CBC with a 256-bit key with "CS1" ciphertext stealing.
+
+ int encrypt(const unsigned char *key, const unsigned char *iv,
+ const unsigned char *msg, size_t msg_len, unsigned char *out)
+ {
+ /*
+ * This assumes that key size is 32 bytes and the iv is 16 bytes.
+ * For ciphertext stealing mode the length of the ciphertext "out" will be
+ * the same size as the plaintext size "msg_len".
+ * The "msg_len" can be any size >= 16.
+ */
+ int ret = 0, encrypt = 1, outlen, len;
+ EVP_CIPHER_CTX *ctx = NULL;
+ EVP_CIPHER *cipher = NULL;
+ OSSL_PARAM params[2];
+
+ ctx = EVP_CIPHER_CTX_new();
+ cipher = EVP_CIPHER_fetch(NULL, "AES-256-CBC-CTS", NULL);
+ if (ctx == NULL || cipher == NULL)
+ goto err;
+
+ if (!EVP_CipherInit_ex(ctx, cipher, NULL, key, iv, encrypt))
+ goto err;
+ /*
+ * The default is "CS1" so this is not really needed,
+ * but would be needed to set either "CS2" or "CS3".
+ */
+ params[0] = OSSL_PARAM_construct_utf8_string(OSSL_CIPHER_PARAM_CTS_MODE,
+ "CS1", 0);
+ params[1] = OSSL_PARAM_construct_end();
+ if (!EVP_CIPHER_CTX_set_params(ctx, params))
+ goto err;
+
+ /* NOTE: CTS mode does not support multiple calls to EVP_CipherUpdate() */
+ if (!EVP_CipherUpdate(ctx, encrypted, &outlen, msg, msglen))
+ goto err;
+ if (!EVP_CipherFinal_ex(ctx, encrypted + outlen, &len))
+ goto err;
+ ret = 1;
+ err:
+ EVP_CIPHER_free(cipher);
+ EVP_CIPHER_CTX_free(ctx);
+ return ret;
+ }
=head1 SEE ALSO
Supported ciphers are listed in:
-L<EVP_aes(3)>,
-L<EVP_aria(3)>,
-L<EVP_bf(3)>,
-L<EVP_camellia(3)>,
-L<EVP_cast5(3)>,
+L<EVP_aes_128_gcm(3)>,
+L<EVP_aria_128_gcm(3)>,
+L<EVP_bf_cbc(3)>,
+L<EVP_camellia_128_ecb(3)>,
+L<EVP_cast5_cbc(3)>,
L<EVP_chacha20(3)>,
-L<EVP_des(3)>,
-L<EVP_desx(3)>,
-L<EVP_idea(3)>,
-L<EVP_rc2(3)>,
+L<EVP_des_cbc(3)>,
+L<EVP_desx_cbc(3)>,
+L<EVP_idea_cbc(3)>,
+L<EVP_rc2_cbc(3)>,
L<EVP_rc4(3)>,
-L<EVP_rc5(3)>,
-L<EVP_seed(3)>,
-L<EVP_sm4(3)>
+L<EVP_rc5_32_12_16_cbc(3)>,
+L<EVP_seed_cbc(3)>,
+L<EVP_sm4_cbc(3)>
=head1 HISTORY
disappeared. EVP_CIPHER_CTX_init() remains as an alias for
EVP_CIPHER_CTX_reset().
+The EVP_CIPHER_fetch(), EVP_CIPHER_free(), EVP_CIPHER_up_ref(),
+EVP_CIPHER_CTX_set_params() and EVP_CIPHER_CTX_get_params() functions
+were added in 3.0.
+
=head1 COPYRIGHT
-Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved.
+Copyright 2000-2020 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
projects / openssl.git / blobdiff