=head1 NAME
-EVP_CIPHER_CTX_init, 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_CIPHER_CTX_cleanup, EVP_EncryptInit,
+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_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_idea_cbc, EVP_rc2_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_gcm, EVP_aes_192_gcm, EVP_aes_256_gcm, EVP_aes_128_ccm,
-EVP_aes_192_ccm, EVP_aes_256_ccm - EVP cipher routines
+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 cipher routines
=head1 SYNOPSIS
#include <openssl/evp.h>
- void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *a);
+ 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);
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_cleanup(EVP_CIPHER_CTX *a);
const EVP_CIPHER *EVP_get_cipherbyname(const char *name);
#define EVP_get_cipherbynid(a) EVP_get_cipherbyname(OBJ_nid2sn(a))
#define EVP_CIPHER_mode(e) ((e)->flags) & EVP_CIPH_MODE)
int EVP_CIPHER_type(const EVP_CIPHER *ctx);
- #define EVP_CIPHER_CTX_cipher(e) ((e)->cipher)
- #define EVP_CIPHER_CTX_nid(e) ((e)->cipher->nid)
- #define EVP_CIPHER_CTX_block_size(e) ((e)->cipher->block_size)
- #define EVP_CIPHER_CTX_key_length(e) ((e)->key_len)
- #define EVP_CIPHER_CTX_iv_length(e) ((e)->cipher->iv_len)
- #define EVP_CIPHER_CTX_get_app_data(e) ((e)->app_data)
- #define EVP_CIPHER_CTX_set_app_data(e,d) ((e)->app_data=(char *)(d))
- #define EVP_CIPHER_CTX_type(c) EVP_CIPHER_type(EVP_CIPHER_CTX_cipher(c))
- #define EVP_CIPHER_CTX_flags(e) ((e)->cipher->flags)
- #define EVP_CIPHER_CTX_mode(e) ((e)->cipher->flags & EVP_CIPH_MODE)
+ const EVP_CIPHER *EVP_CIPHER_CTX_cipher(const EVP_CIPHER_CTX *ctx);
+ int EVP_CIPHER_CTX_nid(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);
+ 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);
+ void EVP_CIPHER_CTX_set_flags(const EVP_CIPHER_CTX *ctx, int flags);
+ void EVP_CIPHER_CTX_clear_flags(const EVP_CIPHER_CTX *ctx, int flags);
+ int EVP_CIPHER_CTX_test_flags(const EVP_CIPHER_CTX *ctx, int flags);
+ int EVP_CIPHER_CTX_mode(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);
The EVP cipher routines are a high level interface to certain
symmetric ciphers.
-EVP_CIPHER_CTX_init() initializes cipher contex B<ctx>.
+EVP_CIPHER_CTX_new() creates a cipher context.
+
+EVP_CIPHER_CTX_free() clears all information from a cipher context
+and free up any allocated memory associate with it, including B<ctx>
+itself. This function should be called after all operations using a
+cipher are complete so sensitive information does not remain in
+memory.
EVP_EncryptInit_ex() sets up cipher context B<ctx> for encryption
-with cipher B<type> from ENGINE B<impl>. B<ctx> must be initialized
+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_des_cbc(). If B<impl> is NULL then the
+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
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
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<outl> should contain sufficient
+to (inl + cipher_block_size - 1) so B<out> should contain sufficient
room. The actual number of bytes written is placed in B<outl>.
If padding is enabled (the default) then EVP_EncryptFinal_ex() encrypts
the "final" data, that is any data that remains in a partial block.
-It uses L<standard block padding|/NOTES> (aka PKCS padding). The encrypted
+It uses standard block padding (aka PKCS padding) as described in
+the NOTES section, below. The encrypted
final data is written to B<out> which should have sufficient space for
one cipher block. The number of bytes written is placed in B<outl>. After
this function is called the encryption operation is finished and no further
If padding is disabled then EVP_EncryptFinal_ex() will not encrypt any more
data and it will return an error if any data remains in a partial block:
-that is if the total data length is not a multiple of the block size.
+that is if the total data length is not a multiple of the block size.
EVP_DecryptInit_ex(), EVP_DecryptUpdate() and EVP_DecryptFinal_ex() are the
corresponding decryption operations. EVP_DecryptFinal() will return an
to 1 for encryption, 0 for decryption and -1 to leave the value unchanged
(the actual value of 'enc' being supplied in a previous call).
-EVP_CIPHER_CTX_cleanup() clears all information from a cipher context
-and free up any allocated memory associate with it. It should be called
-after all operations using a cipher are complete so sensitive information
-does not remain in memory.
+EVP_CIPHER_CTX_reset() clears all information from a cipher context
+and free up any allocated memory associate with it, except the B<ctx>
+itself. This function should be called anytime B<ctx> is to be reused
+for another EVP_CipherInit() / EVP_CipherUpdate() / EVP_CipherFinal()
+series of calls.
EVP_EncryptInit(), EVP_DecryptInit() and EVP_CipherInit() behave in a
similar way to EVP_EncryptInit_ex(), EVP_DecryptInit_ex() and
value is an internal value which may not have a corresponding OBJECT
IDENTIFIER.
-EVP_CIPHER_CTX_set_padding() enables or disables padding. By default
-encryption operations are padded using standard block padding and the
-padding is checked and removed when decrypting. If the B<pad> parameter
-is zero then no padding is 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_CTX_set_padding() enables or disables padding. This
+function should be called after the context is set up for encryption
+or decryption with EVP_EncryptInit_ex(), EVP_DecryptInit_ex() or
+EVP_CipherInit_ex(). By default encryption operations are padded using
+standard block padding and the padding is checked and removed when
+decrypting. If the B<pad> parameter is zero then no padding is
+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_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>
=head1 RETURN VALUES
+EVP_CIPHER_CTX_new() returns a pointer to a newly created
+B<EVP_CIPHER_CTX> for success and B<NULL> for failure.
+
EVP_EncryptInit_ex(), EVP_EncryptUpdate() and EVP_EncryptFinal_ex()
return 1 for success and 0 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_CTX_cleanup() returns 1 for success and 0 for failure.
+EVP_CIPHER_CTX_reset() returns 1 for success and 0 for failure.
EVP_get_cipherbyname(), EVP_get_cipherbynid() and EVP_get_cipherbyobj()
return an B<EVP_CIPHER> structure or NULL on error.
EVP_CIPHER_CTX_cipher() returns an B<EVP_CIPHER> structure.
-EVP_CIPHER_param_to_asn1() and EVP_CIPHER_asn1_to_param() return 1 for
-success or zero for failure.
+EVP_CIPHER_param_to_asn1() and EVP_CIPHER_asn1_to_param() return greater
+than zero for success and zero or a negative number.
=head1 CIPHER LISTING
Null cipher: does nothing.
-=item EVP_des_cbc(void), EVP_des_ecb(void), EVP_des_cfb(void), EVP_des_ofb(void)
+=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.
+DES in CBC, ECB, CFB and OFB modes respectively.
-=item EVP_des_ede_cbc(void), EVP_des_ede(), EVP_des_ede_ofb(void), EVP_des_ede_cfb(void)
+=item EVP_des_ede_cbc(), EVP_des_ede(), EVP_des_ede_ofb(), EVP_des_ede_cfb()
Two key triple DES in CBC, ECB, CFB and OFB modes respectively.
-=item EVP_des_ede3_cbc(void), EVP_des_ede3(), EVP_des_ede3_ofb(void), EVP_des_ede3_cfb(void)
+=item EVP_des_ede3_cbc(), EVP_des_ede3(), EVP_des_ede3_ofb(), EVP_des_ede3_cfb()
Three key triple DES in CBC, ECB, CFB and OFB modes respectively.
-=item EVP_desx_cbc(void)
+=item EVP_desx_cbc()
DESX algorithm in CBC mode.
-=item EVP_rc4(void)
+=item EVP_rc4()
RC4 stream cipher. This is a variable key length cipher with default key length 128 bits.
-=item EVP_rc4_40(void)
+=item EVP_rc4_40()
-RC4 stream cipher with 40 bit key length. This is obsolete and new code should use EVP_rc4()
+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.
-=item EVP_idea_cbc() EVP_idea_ecb(void), EVP_idea_cfb(void), EVP_idea_ofb(void), EVP_idea_cbc(void)
+=item EVP_idea_cbc() EVP_idea_ecb(), EVP_idea_cfb(), EVP_idea_ofb()
IDEA encryption algorithm in CBC, ECB, CFB and OFB modes respectively.
-=item EVP_rc2_cbc(void), EVP_rc2_ecb(void), EVP_rc2_cfb(void), EVP_rc2_ofb(void)
+=item EVP_rc2_cbc(), EVP_rc2_ecb(), EVP_rc2_cfb(), EVP_rc2_ofb()
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.
-=item EVP_rc2_40_cbc(void), EVP_rc2_64_cbc(void)
+=item EVP_rc2_40_cbc(), EVP_rc2_64_cbc()
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.
-=item EVP_bf_cbc(void), EVP_bf_ecb(void), EVP_bf_cfb(void), EVP_bf_ofb(void);
+=item EVP_bf_cbc(), EVP_bf_ecb(), EVP_bf_cfb(), EVP_bf_ofb()
Blowfish encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key
length cipher.
-=item EVP_cast5_cbc(void), EVP_cast5_ecb(void), EVP_cast5_cfb(void), EVP_cast5_ofb(void)
+=item EVP_cast5_cbc(), EVP_cast5_ecb(), EVP_cast5_cfb(), EVP_cast5_ofb()
CAST encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key
length cipher.
-=item EVP_rc5_32_12_16_cbc(void), EVP_rc5_32_12_16_ecb(void), EVP_rc5_32_12_16_cfb(void), EVP_rc5_32_12_16_ofb(void)
+=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()
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.
-=item EVP_aes_128_gcm(void), EVP_aes_192_gcm(void), EVP_aes_256_gcm(void)
+=item EVP_aes_128_gcm(), EVP_aes_192_gcm(), EVP_aes_256_gcm()
AES Galois Counter Mode (GCM) for 128, 192 and 256 bit keys respectively.
These ciphers require additional control operations to function correctly: see
-L<GCM mode> section below for details.
+the L</GCM and OCB modes> section below for details.
-=item EVP_aes_128_ccm(void), EVP_aes_192_ccm(void), EVP_aes_256_ccm(void)
+=item EVP_aes_128_ocb(void), EVP_aes_192_ocb(void), EVP_aes_256_ocb(void)
+
+Offest 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.
+
+=item EVP_aes_128_ccm(), EVP_aes_192_ccm(), EVP_aes_256_ccm()
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
=back
-=head1 GCM Mode
+=head1 GCM and OCB Modes
-For GCM mode ciphers the behaviour of the EVP interface is subtly altered and
-several GCM specific ctrl operations are supported.
+For GCM and OCB 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
+EVP_EncryptUpdate() or EVP_DecryptUpdate() should be made with the output
parameter B<out> set to B<NULL>.
When decrypting the return value of EVP_DecryptFinal() or EVP_CipherFinal()
the authentication operation has failed and any output data B<MUST NOT>
be used as it is corrupted.
-The following ctrls are supported in GCM mode:
+The following ctrls are supported in both GCM and OCB modes:
+
+ EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_IVLEN, ivlen, NULL);
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_IVLEN, ivlen, NULL);
+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.
-Sets the GCM IV length: this call can only be made before specifying an IV. If
-not called a default IV length is used (96 bits for AES).
-
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_GET_TAG, taglen, tag);
+ 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).
+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.
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_TAG, taglen, tag);
+ 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).
+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.
-See L<EXAMPLES> below for an example of the use of GCM mode.
+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.
+
+See L</EXAMPLES> below for an example of the use of GCM mode.
=head1 CCM Mode
-The behaviour of CCM mode ciphers is similar to CCM mode but with a few
+The behaviour of CCM mode ciphers is similar to GCM mode but with a few
additional requirements and different ctrl values.
-Like GCM mode any additional authenticated data (AAD) is passed by calling
-EVP_CipherUpdate(), EVP_EncryptUpdate() or EVP_DecryptUpdate() with the output
+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>)
+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 ctrls are supported in CCM mode:
-
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_CCM_SET_TAG, taglen, tag);
+
+ EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_TAG, taglen, tag);
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.
Sets the CCM B<L> value. If not set a default is used (8 for AES).
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_CCM_SET_IVLEN, ivlen, NULL);
+ 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 nonce value. The nonce length is given by B<15 - L> so it is 7 by default
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
+PKCS padding works by adding B<n> padding bytes of value B<n> to make the total
length of the encrypted data a multiple of the block size. Padding is always
added so if the data is already a multiple of the block size B<n> will equal
the block size. For example if the block size is 8 and 11 bytes are to be
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
+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.
The ASN1 code is incomplete (and sometimes inaccurate) it has only been tested
=head1 EXAMPLES
-Get the number of rounds used in RC5:
-
- int nrounds;
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GET_RC5_ROUNDS, 0, &nrounds);
-
-Get the RC2 effective key length:
-
- int key_bits;
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GET_RC2_KEY_BITS, 0, &key_bits);
-
-Set the number of rounds used in RC5:
-
- int nrounds;
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_SET_RC5_ROUNDS, nrounds, NULL);
-
-Set the effective key length used in RC2:
-
- int key_bits;
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_SET_RC2_KEY_BITS, key_bits, NULL);
-
-Encrypt a string using blowfish:
+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
char intext[] = "Some Crypto Text";
EVP_CIPHER_CTX ctx;
FILE *out;
- EVP_CIPHER_CTX_init(&ctx);
- EVP_EncryptInit_ex(&ctx, EVP_bf_cbc(), NULL, key, iv);
- if(!EVP_EncryptUpdate(&ctx, outbuf, &outlen, intext, strlen(intext)))
+ 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))
+ if(!EVP_EncryptFinal_ex(ctx, outbuf + outlen, &tmplen))
{
/* Error */
return 0;
}
outlen += tmplen;
- EVP_CIPHER_CTX_cleanup(&ctx);
+ EVP_CIPHER_CTX_free(ctx);
/* Need binary mode for fopen because encrypted data is
* binary data. Also cannot use strlen() on it because
* it wont be null terminated and may contain embedded
}
The ciphertext from the above example can be decrypted using the B<openssl>
-utility with the command line:
-
- S<openssl bf -in cipher.bin -K 000102030405060708090A0B0C0D0E0F -iv 0102030405060708 -d>
+utility with the command line (shown on two lines for clarity):
-General encryption, decryption function example using FILE I/O and RC2 with an
-80 bit key:
+ openssl idea -d <filename
+ -K 000102030405060708090A0B0C0D0E0F -iv 0102030405060708
+
+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 */
- inbuf[1024], outbuf[1024 + EVP_MAX_BLOCK_LENGTH];
+ 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[] = "0123456789";
- unsigned char iv[] = "12345678";
- /* Don't set key or IV because we will modify the parameters */
- EVP_CIPHER_CTX_init(&ctx);
- EVP_CipherInit_ex(&ctx, EVP_rc2(), NULL, NULL, NULL, do_encrypt);
- EVP_CIPHER_CTX_set_key_length(&ctx, 10);
- /* We finished modifying parameters so now we can set key and IV */
- EVP_CipherInit_ex(&ctx, NULL, NULL, key, iv, do_encrypt);
-
- for(;;)
+ 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))
+ if(!EVP_CipherUpdate(ctx, outbuf, &outlen, inbuf, inlen))
{
/* Error */
- EVP_CIPHER_CTX_cleanup(&ctx);
+ EVP_CIPHER_CTX_free(ctx);
return 0;
}
fwrite(outbuf, 1, outlen, out);
}
- if(!EVP_CipherFinal_ex(&ctx, outbuf, &outlen))
+ if(!EVP_CipherFinal_ex(ctx, outbuf, &outlen))
{
/* Error */
- EVP_CIPHER_CTX_cleanup(&ctx);
+ EVP_CIPHER_CTX_free(ctx);
return 0;
}
fwrite(outbuf, 1, outlen, out);
- EVP_CIPHER_CTX_cleanup(&ctx);
+ EVP_CIPHER_CTX_free(ctx);
return 1;
}
=head1 SEE ALSO
-L<evp(3)|evp(3)>
+L<evp(3)>
=head1 HISTORY
-EVP_CIPHER_CTX_init(), EVP_EncryptInit_ex(), EVP_EncryptFinal_ex(),
-EVP_DecryptInit_ex(), EVP_DecryptFinal_ex(), EVP_CipherInit_ex(),
-EVP_CipherFinal_ex() and EVP_CIPHER_CTX_set_padding() appeared in
-OpenSSL 0.9.7.
+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().
=cut
projects / openssl.git / blobdiff