RT3462: Document actions when data==NULL

[openssl.git] / doc / crypto / EVP_EncryptInit.pod

diff --git a/doc/crypto/EVP_EncryptInit.pod b/doc/crypto/EVP_EncryptInit.pod
index f6e4396ade3fbf19efaf4b19214a46eae956642e..d68d4bca5bc5288698bf189c06b4e3abbb06fb30 100644 (file)
--- a/doc/crypto/EVP_EncryptInit.pod
+++ b/doc/crypto/EVP_EncryptInit.pod
@@ -24,9 +24,12 @@ 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_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
 
 
 =head1 SYNOPSIS
 


@@ -138,7 +141,7 @@ calls to EVP_EncryptUpdate() should be made.
 
 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:
 
 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
 
 EVP_DecryptInit_ex(), EVP_DecryptUpdate() and EVP_DecryptFinal_ex() are the
 corresponding decryption operations. EVP_DecryptFinal() will return an


@@ -161,14 +164,15 @@ after all operations using a cipher are complete so sensitive information
 does not remain in memory.
 
 EVP_EncryptInit(), EVP_DecryptInit() and EVP_CipherInit() behave in a
 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
+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 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
-similar way to EVP_EncryptFinal_ex(), EVP_DecryptFinal_ex() and
-EVP_CipherFinal_ex() except B<ctx> is automatically cleaned up 
-after the call.
+EVP_EncryptFinal(), EVP_DecryptFinal() and EVP_CipherFinal() are
+identical to EVP_EncryptFinal_ex(), EVP_DecryptFinal_ex() and
+EVP_CipherFinal_ex(). In previous releases they also cleaned up
+the B<ctx>, but this is no longer done and EVP_CIPHER_CTX_clean()
+must be called to free any context resources.

 
 EVP_get_cipherbyname(), EVP_get_cipherbynid() and EVP_get_cipherbyobj()
 return an EVP_CIPHER structure when passed a cipher name, a NID or an
 
 EVP_get_cipherbyname(), EVP_get_cipherbynid() and EVP_get_cipherbyobj()
 return an EVP_CIPHER structure when passed a cipher name, a NID or an


@@ -277,7 +281,7 @@ OBJECT IDENTIFIER or NID_undef if it has no defined OBJECT IDENTIFIER.
 
 EVP_CIPHER_CTX_cipher() returns an B<EVP_CIPHER> structure.
 
 
 EVP_CIPHER_CTX_cipher() returns an B<EVP_CIPHER> structure.
 

-EVP_CIPHER_param_to_asn1() and EVP_CIPHER_asn1_to_param() return 1 for 
+EVP_CIPHER_param_to_asn1() and EVP_CIPHER_asn1_to_param() return 1 for

 success or zero for failure.
 
 =head1 CIPHER LISTING
 success or zero for failure.
 
 =head1 CIPHER LISTING


@@ -290,70 +294,83 @@ All algorithms have a fixed key length unless otherwise stated.
 
 Null cipher: does nothing.
 
 
 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()

 
 

-DES in CBC, ECB, CFB and OFB modes respectively. 
+AES with a 128-bit key 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_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()

 
 Two key triple DES in CBC, ECB, CFB and OFB modes respectively.
 
 
 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.
 
 
 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.
 
 
 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.
 
 
 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.
 
 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(), EVP_idea_cbc()

 
 IDEA encryption algorithm in CBC, ECB, CFB and OFB modes respectively.
 
 
 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.
 
 
 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.
 
 
 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.
 
 
 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.
 
 
 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.
 
 
 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.
 
 
 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)
+=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
 
 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


@@ -367,7 +384,7 @@ 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(),
 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 
+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()
 parameter B<out> set to B<NULL>.
 
 When decrypting the return value of EVP_DecryptFinal() or EVP_CipherFinal()


@@ -381,7 +398,7 @@ The following ctrls are supported in GCM mode:
 
 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).
 
 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>.
  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>.


@@ -392,7 +409,7 @@ processed (e.g. after an EVP_EncryptFinal() call).
 
 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.
 
 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).

 
 See L<EXAMPLES> below for an example of the use of GCM mode.
 
 
 See L<EXAMPLES> below for an example of the use of GCM mode.
 


@@ -402,14 +419,14 @@ 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
 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 
+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
 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:
 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
  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


@@ -433,9 +450,12 @@ for AES.
 
 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
 
 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 
+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
 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


@@ -465,7 +485,7 @@ 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
 
 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
 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


@@ -473,27 +493,7 @@ for certain common S/MIME ciphers (RC2, DES, triple DES) in CBC mode.
 
 =head1 EXAMPLES
 
 
 =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)
        {
 
  int do_crypt(char *outfile)
        {


@@ -507,8 +507,9 @@ Encrypt a string using blowfish:
        char intext[] = "Some Crypto Text";
        EVP_CIPHER_CTX ctx;
        FILE *out;
        char intext[] = "Some Crypto Text";
        EVP_CIPHER_CTX ctx;
        FILE *out;

+

        EVP_CIPHER_CTX_init(&ctx);
        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)))
                {
 
        if(!EVP_EncryptUpdate(&ctx, outbuf, &outlen, intext, strlen(intext)))
                {


@@ -537,31 +538,37 @@ Encrypt a string using blowfish:
        }
 
 The ciphertext from the above example can be decrypted using the B<openssl>
        }
 
 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 */
 
  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;
        int inlen, outlen;

+       EVP_CIPHER_CTX ctx;

        /* Bogus key and IV: we'd normally set these from
         * another source.
         */
        /* 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_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);
 
        EVP_CipherInit_ex(&ctx, NULL, NULL, key, iv, do_encrypt);
 

-       for(;;) 
+       for(;;)

                {
                inlen = fread(inbuf, 1, 1024, in);
                if(inlen <= 0) break;
                {
                inlen = fread(inbuf, 1, 1024, in);
                if(inlen <= 0) break;


@@ -597,4 +604,7 @@ EVP_DecryptInit_ex(), EVP_DecryptFinal_ex(), EVP_CipherInit_ex(),
 EVP_CipherFinal_ex() and EVP_CIPHER_CTX_set_padding() appeared in
 OpenSSL 0.9.7.
 
 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
 =cut