=head1 NAME
-EVP_CIPHER_CTX_new, EVP_CIPHER_CTX_reset, EVP_CIPHER_CTX_free,
-EVP_EncryptInit_ex, EVP_EncryptUpdate, EVP_EncryptFinal_ex,
-EVP_DecryptInit_ex, EVP_DecryptUpdate, EVP_DecryptFinal_ex,
-EVP_CipherInit_ex, EVP_CipherUpdate, EVP_CipherFinal_ex,
-EVP_CIPHER_CTX_set_key_length, EVP_CIPHER_CTX_ctrl, EVP_EncryptInit,
-EVP_EncryptFinal, EVP_DecryptInit, EVP_DecryptFinal,
-EVP_CipherInit, EVP_CipherFinal, EVP_get_cipherbyname,
-EVP_get_cipherbynid, EVP_get_cipherbyobj, EVP_CIPHER_nid,
-EVP_CIPHER_block_size, EVP_CIPHER_key_length, EVP_CIPHER_iv_length,
-EVP_CIPHER_flags, EVP_CIPHER_mode, EVP_CIPHER_type, EVP_CIPHER_CTX_cipher,
-EVP_CIPHER_CTX_nid, EVP_CIPHER_CTX_block_size, EVP_CIPHER_CTX_key_length,
-EVP_CIPHER_CTX_iv_length, EVP_CIPHER_CTX_get_app_data,
-EVP_CIPHER_CTX_set_app_data, EVP_CIPHER_CTX_type, EVP_CIPHER_CTX_flags,
-EVP_CIPHER_CTX_mode, EVP_CIPHER_param_to_asn1, EVP_CIPHER_asn1_to_param,
-EVP_CIPHER_CTX_set_padding, EVP_enc_null, EVP_des_cbc, EVP_des_ecb,
-EVP_des_cfb, EVP_des_ofb, EVP_des_ede_cbc, EVP_des_ede, EVP_des_ede_ofb,
-EVP_des_ede_cfb, EVP_des_ede3_cbc, EVP_des_ede3, EVP_des_ede3_ofb,
-EVP_des_ede3_cfb, EVP_desx_cbc, EVP_rc4, EVP_rc4_40, EVP_idea_cbc,
-EVP_idea_ecb, EVP_idea_cfb, EVP_idea_ofb, EVP_rc2_cbc,
-EVP_rc2_ecb, EVP_rc2_cfb, EVP_rc2_ofb, EVP_rc2_40_cbc, EVP_rc2_64_cbc,
-EVP_bf_cbc, EVP_bf_ecb, EVP_bf_cfb, EVP_bf_ofb, EVP_cast5_cbc,
-EVP_cast5_ecb, EVP_cast5_cfb, EVP_cast5_ofb, EVP_rc5_32_12_16_cbc,
-EVP_rc5_32_12_16_ecb, EVP_rc5_32_12_16_cfb, EVP_rc5_32_12_16_ofb,
-EVP_aes_128_cbc, EVP_aes_128_ecb, EVP_aes_128_cfb, EVP_aes_128_ofb,
-EVP_aes_192_cbc, EVP_aes_192_ecb, EVP_aes_192_cfb, EVP_aes_192_ofb,
-EVP_aes_256_cbc, EVP_aes_256_ecb, EVP_aes_256_cfb, EVP_aes_256_ofb,
-EVP_aes_128_gcm, EVP_aes_192_gcm, EVP_aes_256_gcm,
-EVP_aes_128_ccm, EVP_aes_192_ccm, EVP_aes_256_ccm,
-EVP_chacha20, EVP_chacha20_poly1305 - EVP cipher routines
+EVP_CIPHER_fetch,
+EVP_CIPHER_up_ref,
+EVP_CIPHER_free,
+EVP_CIPHER_CTX_new,
+EVP_CIPHER_CTX_reset,
+EVP_CIPHER_CTX_free,
+EVP_EncryptInit_ex,
+EVP_EncryptUpdate,
+EVP_EncryptFinal_ex,
+EVP_DecryptInit_ex,
+EVP_DecryptUpdate,
+EVP_DecryptFinal_ex,
+EVP_CipherInit_ex,
+EVP_CipherUpdate,
+EVP_CipherFinal_ex,
+EVP_CIPHER_CTX_set_key_length,
+EVP_CIPHER_CTX_ctrl,
+EVP_EncryptInit,
+EVP_EncryptFinal,
+EVP_DecryptInit,
+EVP_DecryptFinal,
+EVP_CipherInit,
+EVP_CipherFinal,
+EVP_get_cipherbyname,
+EVP_get_cipherbynid,
+EVP_get_cipherbyobj,
+EVP_CIPHER_is_a,
+EVP_CIPHER_name,
+EVP_CIPHER_provider,
+EVP_CIPHER_nid,
+EVP_CIPHER_get_params,
+EVP_CIPHER_gettable_params,
+EVP_CIPHER_block_size,
+EVP_CIPHER_key_length,
+EVP_CIPHER_iv_length,
+EVP_CIPHER_flags,
+EVP_CIPHER_mode,
+EVP_CIPHER_type,
+EVP_CIPHER_CTX_cipher,
+EVP_CIPHER_CTX_name,
+EVP_CIPHER_CTX_nid,
+EVP_CIPHER_CTX_get_params,
+EVP_CIPHER_CTX_gettable_params,
+EVP_CIPHER_CTX_set_params,
+EVP_CIPHER_CTX_settable_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_CTX_flags,
+EVP_CIPHER_CTX_mode,
+EVP_CIPHER_param_to_asn1,
+EVP_CIPHER_asn1_to_param,
+EVP_CIPHER_CTX_set_padding,
+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);
+ 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);
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, unsigned char *in, int inl);
- int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out,
- int *outl);
+ 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, unsigned char *in, int inl);
- int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *outm,
- int *outl);
+ 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 EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *outm,
- int *outl);
+ 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);
- int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out,
- int *outl);
+ 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);
- int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *outm,
- int *outl);
+ 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);
- int EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *outm,
- int *outl);
+ 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);
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);
+ int EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX *ctx, unsigned char *key);
const EVP_CIPHER *EVP_get_cipherbyname(const char *name);
const EVP_CIPHER *EVP_get_cipherbynid(int nid);
const EVP_CIPHER *EVP_get_cipherbyobj(const ASN1_OBJECT *a);
int EVP_CIPHER_nid(const EVP_CIPHER *e);
+ int EVP_CIPHER_is_a(const EVP_CIPHER *cipher, const char *name);
+ 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_get_params(EVP_CIPHER *cipher, OSSL_PARAM params[]);
+ 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);
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);
+
=head1 DESCRIPTION
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 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_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
the remaining parameters in subsequent calls, all of which have B<type>
set to NULL. This is done when the default cipher parameters are not
appropriate.
+For EVP_CIPH_GCM_MODE the IV will be generated internally if it is not
+specified.
EVP_EncryptUpdate() encrypts B<inl> bytes from the buffer B<in> and
writes the encrypted version to B<out>. This function can be called
EVP_EncryptInit(), EVP_DecryptInit() and EVP_CipherInit() behave in a
similar way to EVP_EncryptInit_ex(), EVP_DecryptInit_ex() and
-EVP_CipherInit_ex() except the B<ctx> parameter does not need to be
-initialized and they always use the default cipher implementation.
+EVP_CipherInit_ex() except they always use the default cipher implementation.
EVP_EncryptFinal(), EVP_DecryptFinal() and EVP_CipherFinal() are
identical to EVP_EncryptFinal_ex(), EVP_DecryptFinal_ex() and
performed, the total amount of data encrypted or decrypted must then
be a multiple of the block size or an error will occur.
+EVP_CIPHER_get_params() retrieves the requested list of algorithm
+B<params> from a B<cipher>.
+
+EVP_CIPHER_CTX_set_params() Sets the list of operation B<params> into a CIPHER
+context B<ctx>.
+
+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
+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.
+
EVP_CIPHER_key_length() and EVP_CIPHER_CTX_key_length() return the key
length of a cipher when passed an B<EVP_CIPHER> or B<EVP_CIPHER_CTX>
structure. The constant B<EVP_MAX_KEY_LENGTH> is the maximum key length
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 the given I<cipher> is an implementation of an
+algorithm that's identifiable with I<name>, otherwise 0.
+
+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 or
-EVP_CIPH_OFB_MODE. If the cipher is a stream cipher then
-EVP_CIPH_STREAM_CIPHER is returned.
+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, 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
EVP_CIPHER_CTX_ctrl() allows various cipher specific parameters to be determined
and set.
+EVP_CIPHER_CTX_rand_key() generates a random key of the appropriate length
+based on the cipher context. The EVP_CIPHER can provide its own random key
+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_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_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.
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.
=head1 CIPHER LISTING
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
+interface.
+
=over 4
=item EVP_enc_null()
Null cipher: does nothing.
-=item EVP_aes_128_cbc(), EVP_aes_128_ecb(), EVP_aes_128_cfb(), EVP_aes_128_ofb()
-
-AES with a 128-bit key in CBC, ECB, CFB and OFB modes respectively.
-
-=item EVP_aes_192_cbc(), EVP_aes_192_ecb(), EVP_aes_192_cfb(), EVP_aes_192_ofb()
-
-AES with a 192-bit key in CBC, ECB, CFB and OFB modes respectively.
-
-=item EVP_aes_256_cbc(), EVP_aes_256_ecb(), EVP_aes_256_cfb(), EVP_aes_256_ofb()
-
-AES with a 256-bit key in CBC, ECB, CFB and OFB modes respectively.
-
-=item EVP_des_cbc(), EVP_des_ecb(), EVP_des_cfb(), EVP_des_ofb()
-
-DES in CBC, ECB, CFB and OFB modes respectively.
-
-=item EVP_des_ede_cbc(), EVP_des_ede(), EVP_des_ede_ofb(), EVP_des_ede_cfb()
+=back
-Two key triple DES in CBC, ECB, CFB and OFB modes respectively.
+=head1 AEAD INTERFACE
-=item EVP_des_ede3_cbc(), EVP_des_ede3(), EVP_des_ede3_ofb(), EVP_des_ede3_cfb()
+The EVP interface for Authenticated Encryption with Associated Data (AEAD)
+modes are subtly altered and several additional I<ctrl> operations are supported
+depending on the mode specified.
-Three key triple DES in CBC, ECB, CFB and OFB modes respectively.
+To specify additional authenticated data (AAD), a call to EVP_CipherUpdate(),
+EVP_EncryptUpdate() or EVP_DecryptUpdate() should be made with the output
+parameter B<out> set to B<NULL>.
-=item EVP_desx_cbc()
+When decrypting, the return value of EVP_DecryptFinal() or EVP_CipherFinal()
+indicates whether 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.
-DESX algorithm in CBC mode.
+=head2 GCM and OCB Modes
-=item EVP_rc4()
+The following I<ctrl>s are supported in GCM and OCB modes.
-RC4 stream cipher. This is a variable key length cipher with default key length 128 bits.
+=over 4
-=item EVP_rc4_40()
+=item EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_IVLEN, ivlen, NULL)
-RC4 stream cipher with 40 bit key length.
-This is obsolete and new code should use EVP_rc4()
-and the EVP_CIPHER_CTX_set_key_length() function.
+Sets the IV length. This call can only be made before specifying an IV. If
+not called a default IV length is used.
-=item EVP_idea_cbc() EVP_idea_ecb(), EVP_idea_cfb(), EVP_idea_ofb()
+For GCM AES and OCB AES the default is 12 (i.e. 96 bits). For OCB mode the
+maximum is 15.
-IDEA encryption algorithm in CBC, ECB, CFB and OFB modes respectively.
+=item EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_GET_TAG, taglen, tag)
-=item EVP_rc2_cbc(), EVP_rc2_ecb(), EVP_rc2_cfb(), EVP_rc2_ofb()
+Writes C<taglen> bytes of the tag value to the buffer indicated by C<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).
-RC2 encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key
-length cipher with an additional parameter called "effective key bits" or "effective key length".
-By default both are set to 128 bits.
+For OCB, C<taglen> must either be 16 or the value previously set via
+B<EVP_CTRL_AEAD_SET_TAG>.
-=item EVP_rc2_40_cbc(), EVP_rc2_64_cbc()
+=item EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_TAG, taglen, tag)
-RC2 algorithm in CBC mode with a default key length and effective key length of 40 and 64 bits.
-These are obsolete and new code should use EVP_rc2_cbc(), EVP_CIPHER_CTX_set_key_length() and
-EVP_CIPHER_CTX_ctrl() to set the key length and effective key length.
+Sets the expected tag to C<taglen> bytes from C<tag>.
+The tag length can only be set before specifying an IV.
+C<taglen> must be between 1 and 16 inclusive.
-=item EVP_bf_cbc(), EVP_bf_ecb(), EVP_bf_cfb(), EVP_bf_ofb()
+For GCM, this call is only valid when decrypting data.
-Blowfish encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key
-length cipher.
+For OCB, this call is valid when decrypting data to set the expected tag,
+and before encryption to set the desired tag length.
-=item EVP_cast5_cbc(), EVP_cast5_ecb(), EVP_cast5_cfb(), EVP_cast5_ofb()
+In OCB mode, calling this before encryption with C<tag> set to C<NULL> sets the
+tag length. If this is not called prior to encryption, a default tag length is
+used.
-CAST encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key
-length cipher.
+For OCB AES, the default tag length is 16 (i.e. 128 bits). It is also the
+maximum tag length for OCB.
-=item EVP_rc5_32_12_16_cbc(), EVP_rc5_32_12_16_ecb(), EVP_rc5_32_12_16_cfb(), EVP_rc5_32_12_16_ofb()
+=back
-RC5 encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key length
-cipher with an additional "number of rounds" parameter. By default the key length is set to 128
-bits and 12 rounds.
+=head2 CCM Mode
-=item EVP_aes_128_gcm(), EVP_aes_192_gcm(), EVP_aes_256_gcm()
+The EVP interface for CCM mode is similar to that of the GCM mode but with a
+few additional requirements and different I<ctrl> values.
-AES Galois Counter Mode (GCM) for 128, 192 and 256 bit keys respectively.
-These ciphers require additional control operations to function correctly: see
-the L</GCM and OCB Modes> section below for details.
+For CCM mode, the total plaintext or ciphertext length B<MUST> be passed to
+EVP_CipherUpdate(), EVP_EncryptUpdate() or EVP_DecryptUpdate() with the output
+and input parameters (B<in> and B<out>) set to B<NULL> and the length passed in
+the B<inl> parameter.
-=item EVP_aes_128_ocb(void), EVP_aes_192_ocb(void), EVP_aes_256_ocb(void)
+The following I<ctrl>s are supported in CCM mode.
-Offset Codebook Mode (OCB) for 128, 192 and 256 bit keys respectively.
-These ciphers require additional control operations to function correctly: see
-the L</GCM and OCB Modes> section below for details.
+=over 4
-=item EVP_aes_128_ccm(), EVP_aes_192_ccm(), EVP_aes_256_ccm()
+=item EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_TAG, taglen, tag)
-AES Counter with CBC-MAC Mode (CCM) for 128, 192 and 256 bit keys respectively.
-These ciphers require additional control operations to function correctly: see
-CCM mode section below for details.
+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). 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_chacha20()
+=item EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_CCM_SET_L, ivlen, NULL)
-The ChaCha20 stream cipher. The key length is 256 bits, the IV is 96 bits long.
+Sets the CCM B<L> value. If not set a default is used (8 for AES).
-=item EVP_chacha20_poly1305()
+=item EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_IVLEN, ivlen, NULL)
-Authenticated encryption with ChaCha20-Poly1305. Like EVP_chacha20() the key is
-256 bits and the IV is 96 bits. This supports additional authenticated
-data (AAD) and produces a 128 bit authentication tag. See the
-L</GCM and OCB Modes> section for more information.
+Sets the CCM nonce (IV) length. This call can only be made before specifying an
+nonce value. The nonce length is given by B<15 - L> so it is 7 by default for
+AES.
=back
-=head1 GCM and OCB Modes
+=head2 SIV Mode
-For GCM and OCB mode ciphers the behaviour of the EVP interface is subtly
+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) a call to EVP_CipherUpdate(),
-EVP_EncryptUpdate() or EVP_DecryptUpdate() should be made with the output
-parameter B<out> set to B<NULL>.
+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 GCM and OCB modes:
-
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_IVLEN, ivlen, NULL);
+The following ctrls are supported in both SIV modes.
-Sets the IV length: this call can only be made before specifying an IV. If
-not called a default IV length is used. For GCM AES and OCB AES the default is
-12 (i.e. 96 bits). For OCB mode the maximum is 15.
+=over 4
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_GET_TAG, taglen, tag);
+=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 OCB mode the taglen must
-either be 16 or the value previously set via EVP_CTRL_OCB_SET_TAGLEN.
+processed (e.g. after an EVP_EncryptFinal() call). For SIV mode the taglen must
+be 16.
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_TAG, taglen, tag);
+=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 OCB mode the taglen must
-either be 16 or the value previously set via EVP_CTRL_AEAD_SET_TAG.
+before any EVP_DecryptUpdate() call). For SIV mode the taglen must be 16.
-In OCB mode calling this with B<tag> set to NULL sets the tag length. The tag
-length can only be set before specifying an IV. If not called a default tag
-length is used. For OCB AES the default is 16 (i.e. 128 bits). This is also the
-maximum tag length for OCB.
+=back
-=head1 CCM Mode
+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.
-The behaviour of CCM mode ciphers is similar to GCM mode but with a few
-additional requirements and different ctrl values.
+=head2 ChaCha20-Poly1305
-Like GCM and OCB modes any additional authenticated data (AAD) is passed by calling
-EVP_CipherUpdate(), EVP_EncryptUpdate() or EVP_DecryptUpdate() with the output
-parameter B<out> set to B<NULL>. Additionally the total plaintext or ciphertext
-length B<MUST> be passed to EVP_CipherUpdate(), EVP_EncryptUpdate() or
-EVP_DecryptUpdate() with the output and input parameters (B<in> and B<out>)
-set to B<NULL> and the length passed in the B<inl> parameter.
+The following I<ctrl>s are supported for the ChaCha20-Poly1305 AEAD algorithm.
-The following ctrls are supported in CCM mode:
+=over 4
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_TAG, taglen, tag);
+=item EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_IVLEN, ivlen, NULL)
-This call is made to set the expected B<CCM> tag value when decrypting or
-the length of the tag (with the B<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).
+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 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.
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_CCM_SET_L, ivlen, NULL);
+=item EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_GET_TAG, taglen, tag)
-Sets the CCM B<L> value. If not set a default is used (8 for AES).
+Writes C<taglen> bytes of the tag value to the buffer indicated by C<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).
+
+C<taglen> specified here must be 16 (B<POLY1305_BLOCK_SIZE>, i.e. 128-bits) or
+less.
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_IVLEN, ivlen, NULL);
+=item EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_TAG, taglen, tag)
-Sets the CCM nonce (IV) length: this call can only be made before specifying
-an nonce value. The nonce length is given by B<15 - L> so it is 7 by default
-for AES.
+Sets the expected tag to C<taglen> bytes from C<tag>.
+The tag length can only be set before specifying an IV.
+C<taglen> must be between 1 and 16 (B<POLY1305_BLOCK_SIZE>) inclusive.
+This call is only valid when decrypting data.
+
+=back
=head1 NOTES
=head1 BUGS
-For RC5 the number of rounds can currently only be set to 8, 12 or 16. This is
-a limitation of the current RC5 code rather than the EVP interface.
-
-EVP_MAX_KEY_LENGTH and EVP_MAX_IV_LENGTH only refer to the internal ciphers with
-default key lengths. If custom ciphers exceed these values the results are
-unpredictable. This is because it has become standard practice to define a
-generic key as a fixed unsigned char array containing EVP_MAX_KEY_LENGTH bytes.
+B<EVP_MAX_KEY_LENGTH> and B<EVP_MAX_IV_LENGTH> only refer to the internal
+ciphers with default key lengths. If custom ciphers exceed these values the
+results are unpredictable. This is because it has become standard practice to
+define a generic key as a fixed unsigned char array containing
+B<EVP_MAX_KEY_LENGTH> bytes.
The ASN1 code is incomplete (and sometimes inaccurate) it has only been tested
for certain common S/MIME ciphers (RC2, DES, triple DES) in CBC mode.
Encrypt a string using IDEA:
int do_crypt(char *outfile)
- {
- unsigned char outbuf[1024];
- int outlen, tmplen;
- /* Bogus key and IV: we'd normally set these from
- * another source.
- */
- unsigned char key[] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
- unsigned char iv[] = {1,2,3,4,5,6,7,8};
- char intext[] = "Some Crypto Text";
- EVP_CIPHER_CTX ctx;
- FILE *out;
-
- ctx = EVP_CIPHER_CTX_new();
- EVP_EncryptInit_ex(ctx, EVP_idea_cbc(), NULL, key, iv);
-
- if(!EVP_EncryptUpdate(ctx, outbuf, &outlen, intext, strlen(intext)))
- {
- /* Error */
- return 0;
- }
- /* Buffer passed to EVP_EncryptFinal() must be after data just
- * encrypted to avoid overwriting it.
- */
- if(!EVP_EncryptFinal_ex(ctx, outbuf + outlen, &tmplen))
- {
- /* Error */
- return 0;
- }
- outlen += tmplen;
- EVP_CIPHER_CTX_free(ctx);
- /* Need binary mode for fopen because encrypted data is
- * binary data. Also cannot use strlen() on it because
- * it won't be null terminated and may contain embedded
- * nulls.
- */
- out = fopen(outfile, "wb");
- fwrite(outbuf, 1, outlen, out);
- fclose(out);
- return 1;
- }
+ {
+ unsigned char outbuf[1024];
+ int outlen, tmplen;
+ /*
+ * Bogus key and IV: we'd normally set these from
+ * another source.
+ */
+ unsigned char key[] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
+ unsigned char iv[] = {1,2,3,4,5,6,7,8};
+ char intext[] = "Some Crypto Text";
+ EVP_CIPHER_CTX *ctx;
+ FILE *out;
+
+ ctx = EVP_CIPHER_CTX_new();
+ EVP_EncryptInit_ex(ctx, EVP_idea_cbc(), NULL, key, iv);
+
+ if (!EVP_EncryptUpdate(ctx, outbuf, &outlen, intext, strlen(intext))) {
+ /* Error */
+ EVP_CIPHER_CTX_free(ctx);
+ return 0;
+ }
+ /*
+ * Buffer passed to EVP_EncryptFinal() must be after data just
+ * encrypted to avoid overwriting it.
+ */
+ if (!EVP_EncryptFinal_ex(ctx, outbuf + outlen, &tmplen)) {
+ /* Error */
+ EVP_CIPHER_CTX_free(ctx);
+ return 0;
+ }
+ outlen += tmplen;
+ EVP_CIPHER_CTX_free(ctx);
+ /*
+ * Need binary mode for fopen because encrypted data is
+ * binary data. Also cannot use strlen() on it because
+ * it won't be NUL terminated and may contain embedded
+ * NULs.
+ */
+ out = fopen(outfile, "wb");
+ if (out == NULL) {
+ /* Error */
+ return 0;
+ }
+ fwrite(outbuf, 1, outlen, out);
+ fclose(out);
+ return 1;
+ }
The ciphertext from the above example can be decrypted using the B<openssl>
utility with the command line (shown on two lines for clarity):
- openssl idea -d <filename
- -K 000102030405060708090A0B0C0D0E0F -iv 0102030405060708
+ openssl idea -d \
+ -K 000102030405060708090A0B0C0D0E0F -iv 0102030405060708 <filename
General encryption and decryption function example using FILE I/O and AES128
with a 128-bit key:
int do_crypt(FILE *in, FILE *out, int do_encrypt)
- {
- /* Allow enough space in output buffer for additional block */
- unsigned char inbuf[1024], outbuf[1024 + EVP_MAX_BLOCK_LENGTH];
- int inlen, outlen;
- EVP_CIPHER_CTX *ctx;
- /* Bogus key and IV: we'd normally set these from
- * another source.
- */
- unsigned char key[] = "0123456789abcdeF";
- unsigned char iv[] = "1234567887654321";
-
- /* 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,
- do_encrypt);
- OPENSSL_assert(EVP_CIPHER_CTX_key_length(ctx) == 16);
- OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) == 16);
-
- /* Now we can set key and IV */
- EVP_CipherInit_ex(ctx, NULL, NULL, key, iv, do_encrypt);
-
- for(;;)
- {
- inlen = fread(inbuf, 1, 1024, in);
- if (inlen <= 0) break;
- if(!EVP_CipherUpdate(ctx, outbuf, &outlen, inbuf, inlen))
- {
- /* Error */
- EVP_CIPHER_CTX_free(ctx);
- return 0;
- }
- fwrite(outbuf, 1, outlen, out);
- }
- if(!EVP_CipherFinal_ex(ctx, outbuf, &outlen))
- {
- /* Error */
- EVP_CIPHER_CTX_free(ctx);
- return 0;
- }
- fwrite(outbuf, 1, outlen, out);
-
- EVP_CIPHER_CTX_free(ctx);
- return 1;
- }
+ {
+ /* Allow enough space in output buffer for additional block */
+ unsigned char inbuf[1024], outbuf[1024 + EVP_MAX_BLOCK_LENGTH];
+ int inlen, outlen;
+ EVP_CIPHER_CTX *ctx;
+ /*
+ * Bogus key and IV: we'd normally set these from
+ * another source.
+ */
+ unsigned char key[] = "0123456789abcdeF";
+ unsigned char iv[] = "1234567887654321";
+
+ /* 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,
+ do_encrypt);
+ OPENSSL_assert(EVP_CIPHER_CTX_key_length(ctx) == 16);
+ OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) == 16);
+
+ /* Now we can set key and IV */
+ EVP_CipherInit_ex(ctx, NULL, NULL, key, iv, do_encrypt);
+
+ for (;;) {
+ inlen = fread(inbuf, 1, 1024, in);
+ if (inlen <= 0)
+ break;
+ if (!EVP_CipherUpdate(ctx, outbuf, &outlen, inbuf, inlen)) {
+ /* Error */
+ EVP_CIPHER_CTX_free(ctx);
+ return 0;
+ }
+ fwrite(outbuf, 1, outlen, out);
+ }
+ if (!EVP_CipherFinal_ex(ctx, outbuf, &outlen)) {
+ /* Error */
+ EVP_CIPHER_CTX_free(ctx);
+ return 0;
+ }
+ fwrite(outbuf, 1, outlen, out);
+
+ EVP_CIPHER_CTX_free(ctx);
+ return 1;
+ }
=head1 SEE ALSO
L<evp(7)>
+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_chacha20(3)>,
+L<EVP_des(3)>,
+L<EVP_desx(3)>,
+L<EVP_idea(3)>,
+L<EVP_rc2(3)>,
+L<EVP_rc4(3)>,
+L<EVP_rc5(3)>,
+L<EVP_seed(3)>,
+L<EVP_sm4(3)>
+
=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()
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 2000-2016 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