EVP_EncryptInit(3)          OpenSSL          EVP_EncryptInit(3)





NAME
       EVP_CIPHER_CTX_init, EVP_EncryptInit_ex, EVP_EncryptUp-
       date, 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_EncryptFi-
       nal, EVP_DecryptInit, EVP_DecryptFinal, EVP_CipherInit,
       EVP_CipherFinal, EVP_get_cipherbyname, EVP_get_cipher-
       bynid, 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 cipher routines

SYNOPSIS
        #include <openssl/evp.h>

        int EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *a);

        int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
                ENGINE *impl, unsigned char *key, 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 EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
                ENGINE *impl, unsigned char *key, 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 EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
                ENGINE *impl, unsigned char *key, 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 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);

        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);

        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);



        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_get_cipherbyobj(a) EVP_get_cipherbynid(OBJ_obj2nid(a))

        #define EVP_CIPHER_nid(e)              ((e)->nid)
        #define EVP_CIPHER_block_size(e)       ((e)->block_size)
        #define EVP_CIPHER_key_length(e)       ((e)->key_len)
        #define EVP_CIPHER_iv_length(e)                ((e)->iv_len)
        #define EVP_CIPHER_flags(e)            ((e)->flags)
        #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)

        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);

DESCRIPTION
       The EVP cipher routines are a high level interface to
       certain symmetric ciphers.

       EVP_CIPHER_CTX_init() initializes cipher contex ctx.

       EVP_EncryptInit_ex() sets up cipher context ctx for
       encryption with cipher type from ENGINE impl. ctx must
       be initialized before calling this function. type is
       normally supplied by a function such as EVP_des_cbc().
       If impl is NULL then the default implementation is used.
       key is the symmetric key to use and 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 type in an initial call
       and supply the remaining parameters in subsequent calls,
       all of which have type set to NULL. This is done when
       the default cipher parameters are not appropriate.

       EVP_EncryptUpdate() encrypts inl bytes from the buffer
       in and writes the encrypted version to out. This func-
       tion 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 outl should
       contain sufficient room. The actual number of bytes
       written is placed in outl.

       If padding is enabled (the default) then EVP_EncryptFi-
       nal_ex() encrypts the "final" data, that is any data
       that remains in a partial block.  It uses standard block
       padding (aka PKCS padding). The encrypted final data is
       written to out which should have sufficient space for
       one cipher block. The number of bytes written is placed
       in outl. After this function is called the encryption
       operation is finished and no further 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: 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 error code
       if padding is enabled and the final block is not cor-
       rectly formatted. The parameters and restrictions are
       identical to the encryption operations except that if
       padding is enabled the decrypted data buffer out passed
       to EVP_DecryptUpdate() should have sufficient room for
       (inl + cipher_block_size) bytes unless the cipher block
       size is 1 in which case inl bytes is sufficient.

       EVP_CipherInit_ex(), EVP_CipherUpdate() and EVP_Cipher-
       Final_ex() are functions that can be used for decryption
       or encryption. The operation performed depends on the
       value of the enc parameter. It should be set 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 asso-
       ciate with it. It should be called 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 similar way to EVP_Encryp-
       tInit_ex(), EVP_DecryptInit_ex and EVP_CipherInit_ex()
       except the ctx paramter does not need to be initialized
       and they always use the default cipher implementation.

       EVP_EncryptFinal(), EVP_DecryptFinal() and EVP_CipherFi-
       nal() behave in a similar way to EVP_EncryptFinal_ex(),
       EVP_DecryptFinal_ex() and EVP_CipherFinal_ex() except
       ctx is automatically cleaned up after the call.

       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_nid() and EVP_CIPHER_CTX_nid() return the NID
       of a cipher when passed an EVP_CIPHER or EVP_CIPHER_CTX
       structure.  The actual NID value is an internal value
       which may not have a corresponding OBJECT IDENTIFIER.

       EVP_CIPHER_CTX_set_padding() enables or disables pad-
       ding. By default encryption operations are padded using
       standard block padding and the padding is checked and
       removed when decrypting. If the 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
       EVP_CIPHER or EVP_CIPHER_CTX structure. The constant
       EVP_MAX_KEY_LENGTH is the maximum key length for all
       ciphers. Note: although EVP_CIPHER_key_length() is fixed
       for a given cipher, the value of
       EVP_CIPHER_CTX_key_length() may be different for vari-
       able key length ciphers.

       EVP_CIPHER_CTX_set_key_length() sets the key length of
       the cipher ctx.  If the cipher is a fixed length cipher
       then attempting to set the key length to any value other
       than the fixed value is an error.

       EVP_CIPHER_iv_length() and EVP_CIPHER_CTX_iv_length()
       return the IV length of a cipher when passed an
       EVP_CIPHER or EVP_CIPHER_CTX.  It will return zero if
       the cipher does not use an IV.  The constant
       EVP_MAX_IV_LENGTH is the maximum IV length for all
       ciphers.

       EVP_CIPHER_block_size() and EVP_CIPHER_CTX_block_size()
       return the block size of a cipher when passed an
       EVP_CIPHER or EVP_CIPHER_CTX structure. The constant
       EVP_MAX_IV_LENGTH is also the maximum block length for
       all ciphers.

       EVP_CIPHER_type() and EVP_CIPHER_CTX_type() return the
       type of the passed cipher or context. This "type" is the
       actual NID of the cipher OBJECT IDENTIFIER as such it
       ignores the cipher parameters and 40 bit RC2 and 128 bit
       RC2 have the same NID. If the cipher does not have an
       object identifier or does not have ASN1 support this
       function will return NID_undef.

       EVP_CIPHER_CTX_cipher() returns the EVP_CIPHER structure
       when passed an 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_CIPHER_param_to_asn1() sets the AlgorithmIdentifier
       "parameter" based on the passed cipher. This will typi-
       cally include any parameters and an IV. The cipher IV
       (if any) must be set when this call is made. This call
       should be made before the cipher is actually "used"
       (before any EVP_EncryptUpdate(), EVP_DecryptUpdate()
       calls for example). This function may fail if the cipher
       does not have any ASN1 support.

       EVP_CIPHER_asn1_to_param() sets the cipher parameters
       based on an ASN1 AlgorithmIdentifier "parameter". The
       precise effect depends on the cipher In the case of RC2,
       for example, it will set the IV and effective key
       length.  This function should be called after the base
       cipher type is set but before the key is set. For exam-
       ple EVP_CipherInit() will be called with the IV and key
       set to NULL, EVP_CIPHER_asn1_to_param() will be called
       and finally EVP_CipherInit() again with all parameters
       except the key set to NULL. It is possible for this
       function to fail if the cipher does not have any ASN1
       support 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.

RETURN VALUES
       EVP_CIPHER_CTX_init, EVP_EncryptInit_ex(), EVP_Encryp-
       tUpdate() and EVP_EncryptFinal_ex() return 1 for success
       and 0 for failure.

       EVP_DecryptInit_ex() and EVP_DecryptUpdate() return 1
       for success and 0 for failure.  EVP_DecryptFinal_ex()
       returns 0 if the decrypt failed or 1 for success.

       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_get_cipherbyname(), EVP_get_cipherbynid() and
       EVP_get_cipherbyobj() return an EVP_CIPHER structure or
       NULL on error.

       EVP_CIPHER_nid() and EVP_CIPHER_CTX_nid() return a NID.

       EVP_CIPHER_block_size() and EVP_CIPHER_CTX_block_size()
       return the block size.

       EVP_CIPHER_key_length() and EVP_CIPHER_CTX_key_length()
       return the key length.

       EVP_CIPHER_CTX_set_padding() always returns 1.

       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_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 EVP_CIPHER structure.

       EVP_CIPHER_param_to_asn1() and
       EVP_CIPHER_asn1_to_param() return 1 for success or zero
       for failure.

CIPHER LISTING
       All algorithms have a fixed key length unless otherwise
       stated.

       EVP_enc_null()
           Null cipher: does nothing.

       EVP_des_cbc(void), EVP_des_ecb(void), EVP_des_cfb(void),
       EVP_des_ofb(void)
           DES in CBC, ECB, CFB and OFB modes respectively.

       EVP_des_ede_cbc(void), EVP_des_ede(),
       EVP_des_ede_ofb(void),  EVP_des_ede_cfb(void)
           Two key triple DES in CBC, ECB, CFB and OFB modes
           respectively.

       EVP_des_ede3_cbc(void), EVP_des_ede3(),
       EVP_des_ede3_ofb(void),  EVP_des_ede3_cfb(void)
           Three key triple DES in CBC, ECB, CFB and OFB modes
           respectively.

       EVP_desx_cbc(void)
           DESX algorithm in CBC mode.

       EVP_rc4(void)
           RC4 stream cipher. This is a variable key length
           cipher with default key length 128 bits.

       EVP_rc4_40(void)
           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.

       EVP_idea_cbc() EVP_idea_ecb(void), EVP_idea_cfb(void),
       EVP_idea_ofb(void), EVP_idea_cbc(void)
           IDEA encryption algorithm in CBC, ECB, CFB and OFB
           modes respectively.

       EVP_rc2_cbc(void), EVP_rc2_ecb(void), EVP_rc2_cfb(void),
       EVP_rc2_ofb(void)
           RC2 encryption algorithm in CBC, ECB, CFB and OFB
           modes respectively. This is a variable key length
           cipher with an additional parameter called "effec-
           tive key bits" or "effective key length".  By
           default both are set to 128 bits.

       EVP_rc2_40_cbc(void), EVP_rc2_64_cbc(void)
           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.

       EVP_bf_cbc(void), EVP_bf_ecb(void), EVP_bf_cfb(void),
       EVP_bf_ofb(void);
           Blowfish encryption algorithm in CBC, ECB, CFB and
           OFB modes respectively. This is a variable key
           length cipher.

       EVP_cast5_cbc(void), EVP_cast5_ecb(void),
       EVP_cast5_cfb(void), EVP_cast5_ofb(void)
           CAST encryption algorithm in CBC, ECB, CFB and OFB
           modes respectively. This is a variable key length
           cipher.

       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)
           RC5 encryption algorithm in CBC, ECB, CFB and OFB
           modes respectively. This is a variable key length
           cipher with an additional "number of rounds" parame-
           ter. By default the key length is set to 128 bits
           and 12 rounds.

NOTES
       Where possible the EVP interface to symmetric ciphers
       should be used in preference to the low level inter-
       faces. This is because the code then becomes transparent
       to the cipher used and much more flexible.

       PKCS padding works by adding n padding bytes of value n
       to make the total length of the encrypted data a multi-
       ple of the block size. Padding is always added so if the
       data is already a multiple of the block size n will
       equal the block size. For example if the block size is 8
       and 11 bytes are to be encrypted then 5 padding bytes of
       value 5 will be added.

       When decrypting the final block is checked to see if it
       has the correct form.

       Although the decryption operation can produce an error
       if padding is enabled, it is not a strong test that the
       input data or key is correct. A random block has better
       than 1 in 256 chance of being of the correct format and
       problems with the input data earlier on will not produce
       a final decrypt error.

       If padding is disabled then the decryption operation
       will always succeed if the total amount of data
       decrypted is a multiple of the block size.

       The functions EVP_EncryptInit(), EVP_EncryptFinal(),
       EVP_DecryptInit(), EVP_CipherInit() and EVP_CipherFi-
       nal() are obsolete but are retained for compatibility
       with existing code. New code should use
       EVP_EncryptInit_ex(), EVP_EncryptFinal_ex(), EVP_Decryp-
       tInit_ex(), EVP_DecryptFinal_ex(), EVP_CipherInit_ex()
       and EVP_CipherFinal_ex() because they can reuse an
       existing context without allocating and freeing it up on
       each call.

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 unpre-
       dictable. This is because it has become standard prac-
       tice 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 for certain common S/MIME
       ciphers (RC2, DES, triple DES) in CBC mode.

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:

        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;
               EVP_CIPHER_CTX_init(&ctx);
               EVP_EncryptInit_ex(&ctx, EVP_bf_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_cleanup(&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
                * nulls.
                */
               out = fopen(outfile, "wb");
               fwrite(outbuf, 1, outlen, out);
               fclose(out);
               return 1;
               }

       The ciphertext from the above example can be decrypted
       using the openssl utility with the command line:

        S<openssl bf -in cipher.bin -K 000102030405060708090A0B0C0D0E0F -iv 0102030405060708 -d>

       General encryption, decryption function example using
       FILE I/O and RC2 with an 80 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];
               int inlen, outlen;
               /* 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(;;)
                       {
                       inlen = fread(inbuf, 1, 1024, in);
                       if(inlen <= 0) break;
                       if(!EVP_CipherUpdate(&ctx, outbuf, &outlen, inbuf, inlen))
                               {
                               /* Error */
                               return 0;
                               }
                       fwrite(outbuf, 1, outlen, out);
                       }
               if(!EVP_CipherFinal_ex(&ctx, outbuf, &outlen))
                       {
                       /* Error */
                       return 0;
                       }
               fwrite(outbuf, 1, outlen, out);


               EVP_CIPHER_CTX_cleanup(&ctx);
               return 1;
               }

SEE ALSO
       evp(3)

HISTORY
       EVP_CIPHER_CTX_init(), EVP_EncryptInit_ex(),
       EVP_EncryptFinal_ex(), EVP_DecryptInit_ex(),
       EVP_DecryptFinal_ex(), EVP_CipherInit_ex(), EVP_Cipher-
       Final_ex() and EVP_CIPHER_CTX_set_padding() appeared in
       OpenSSL 0.9.7.



0.9.7c                     2002-10-18        EVP_EncryptInit(3)
