This commit is contained in:
Zhi Guan
2015-08-15 15:02:15 +08:00
parent 06df2fab54
commit 3bdc0ea895
2536 changed files with 417052 additions and 271997 deletions

View File

@@ -16,7 +16,17 @@ 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 cipher routines
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_idea_cbc, 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
=head1 SYNOPSIS
@@ -115,7 +125,7 @@ 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<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
@@ -152,7 +162,7 @@ does not remain in memory.
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> paramter does not need to be
EVP_CipherInit_ex() except the B<ctx> parameter does not need to be
initialized and they always use the default cipher implementation.
EVP_EncryptFinal(), EVP_DecryptFinal() and EVP_CipherFinal() behave in a
@@ -231,8 +241,7 @@ or the parameters cannot be set (for example the RC2 effective key length
is not supported.
EVP_CIPHER_CTX_ctrl() allows various cipher specific parameters to be determined
and set. Currently only the RC2 effective key length and the number of rounds of
RC5 can be set.
and set.
=head1 RETURN VALUES
@@ -338,13 +347,96 @@ RC5 encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a
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)
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.
=item EVP_aes_128_ccm(void), EVP_aes_192_ccm(void), EVP_aes_256_ccm(void)
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.
=back
=head1 GCM Mode
For GCM mode ciphers the behaviour of the EVP interface is subtly altered and
several GCM specific 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>.
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 GCM mode:
EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_IVLEN, ivlen, NULL);
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);
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).
EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_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).
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
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
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 ctrls are supported in CCM mode:
EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_CCM_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.
The tag length is often referred to as B<M>. If not set a default value is
used (12 for AES).
EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_CCM_SET_L, ivlen, NULL);
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);
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.
=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
transparent to the cipher used and much more flexible.
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
guarantee).
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
@@ -384,27 +476,7 @@ for certain common S/MIME ciphers (RC2, DES, triple DES) in CBC mode.
=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)
{
@@ -418,8 +490,9 @@ Encrypt a string using blowfish:
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);
EVP_EncryptInit_ex(&ctx, EVP_idea_cbc(), NULL, key, iv);
if(!EVP_EncryptUpdate(&ctx, outbuf, &outlen, intext, strlen(intext)))
{
@@ -448,28 +521,34 @@ Encrypt a string using blowfish:
}
The ciphertext from the above example can be decrypted using the B<openssl>
utility with the command line:
utility with the command line (shown on two lines for clarity):
S<openssl bf -in cipher.bin -K 000102030405060708090A0B0C0D0E0F -iv 0102030405060708 -d>
openssl idea -d <filename
-K 000102030405060708090A0B0C0D0E0F -iv 0102030405060708
General encryption, decryption function example using FILE I/O and RC2 with an
80 bit key:
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 */
unsigned char key[] = "0123456789abcdeF";
unsigned char iv[] = "1234567887654321";
/* Don't set key or IV right away; we want to check lengths */
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, 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(;;)
@@ -508,4 +587,7 @@ EVP_DecryptInit_ex(), EVP_DecryptFinal_ex(), EVP_CipherInit_ex(),
EVP_CipherFinal_ex() and EVP_CIPHER_CTX_set_padding() appeared in
OpenSSL 0.9.7.
IDEA appeared in OpenSSL 0.9.7 but was often disabled due to
patent concerns; the last patents expired in 2012.
=cut