MirOS Manual: EVP_CipherFinal(3), EVP_CipherInit(3), EVP_CipherUpdate(3), EVP_CIPHER_asn1_to_param(3), EVP_CIPHER_block_size(3), EVP_CIPHER_CTX_block_size(3), EVP_CIPHER_CTX_cipher(3), EVP_CIPHER_CTX_cleanup(3), EVP_CIPHER_CTX_ctrl(3), EVP_CIPHER_CTX_iv_length(3), EVP_CIPHER_CTX_key_length(3), EVP_CIPHER_CTX_nid(3), EVP_CIPHER_CTX_set_key_length(3), EVP_CIPHER_CTX_type(3), EVP_CIPHER_iv_length(3), EVP_CIPHER_key_length(3), EVP_CIPHER_nid(3), EVP_CIPHER_param_to_asn1(3), EVP_CIPHER_type(3), EVP_DecryptFinal(3), EVP_DecryptInit(3), EVP_DecryptUpdate(3), EVP_EncryptFinal(3), EVP_EncryptInit(3), EVP_EncryptUpdate(3), EVP_get_cipherbyname(3), EVP_get_cipherbynid(3), EVP_get_cipherbyobj(3), OBJ_nid2sn(3), OBJ_obj2nid(3)


EVP_ENCRYPTINIT(3)           OpenSSL           EVP_ENCRYPTINIT(3)

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_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 cipher routines

SYNOPSIS

      #include <openssl/evp.h>

      void 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);

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      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 cer-
     tain symmetric ciphers.

     EVP_CIPHER_CTX_init() initializes cipher contex ctx.

     EVP_EncryptInit_ex() sets up cipher context ctx for encryp-
     tion with cipher type from ENGINE impl. ctx must be initial-
     ized 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

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     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 function can
     be called multiple times to encrypt successive blocks of
     data. The amount of data written depends on the block align-
     ment 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_EncryptFinal_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 correctly for-
     matted. 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_CipherFinal_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).

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EVP_ENCRYPTINIT(3)           OpenSSL           EVP_ENCRYPTINIT(3)

     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_EncryptInit(), EVP_DecryptInit() and EVP_CipherInit()
     behave in a similar way to EVP_EncryptInit_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_CipherFinal()
     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 struc-
     ture.  The actual NID 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 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
     variable 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.

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EVP_ENCRYPTINIT(3)           OpenSSL           EVP_ENCRYPTINIT(3)

     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 typically
     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 exam-
     ple, it will set the IV and effective key length. This func-
     tion should be called after the base cipher type is set but
     before the key is set. For example 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 can-
     not be set (for example the RC2 effective key length is not
     supported.

     EVP_CIPHER_CTX_ctrl() allows various cipher specific parame-
     ters to be determined and set. Currently only the RC2 effec-
     tive key length can be set.

RETURN VALUES

     EVP_EncryptInit_ex(), EVP_EncryptUpdate() and
     EVP_EncryptFinal_ex() return 1 for success and 0 for
     failure.

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EVP_ENCRYPTINIT(3)           OpenSSL           EVP_ENCRYPTINIT(3)

     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 suc-
     cess 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.

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EVP_ENCRYPTINIT(3)           OpenSSL           EVP_ENCRYPTINIT(3)

     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_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 "effective 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 effec-
         tive 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.

NOTES

     Where possible the 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.

     PKCS padding works by adding n padding bytes of value n to
     make the total length of the encrypted data a multiple of

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EVP_ENCRYPTINIT(3)           OpenSSL           EVP_ENCRYPTINIT(3)

     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_CipherFinal()
     are obsolete but are retained for compatibility with exist-
     ing code. New code should use EVP_EncryptInit_ex(),
     EVP_EncryptFinal_ex(), EVP_DecryptInit_ex(),
     EVP_DecryptFinal_ex(), EVP_CipherInit_ex() and
     EVP_CipherFinal_ex() because they can reuse an existing con-
     text without allocating and freeing it up on each call.

BUGS

     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.

     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 RC2 effective key length:

      int key_bits;
      EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GET_RC2_KEY_BITS, 0, &key_bits);

     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);

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EVP_ENCRYPTINIT(3)           OpenSSL           EVP_ENCRYPTINIT(3)

     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:

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EVP_ENCRYPTINIT(3)           OpenSSL           EVP_ENCRYPTINIT(3)

      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 */
                             EVP_CIPHER_CTX_cleanup(&ctx);
                             return 0;
                             }
                     fwrite(outbuf, 1, outlen, out);
                     }
             if(!EVP_CipherFinal_ex(&ctx, outbuf, &outlen))
                     {
                     /* Error */
                     EVP_CIPHER_CTX_cleanup(&ctx);
                     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_CipherFinal_ex() and EVP_CIPHER_CTX_set_padding()
     appeared in OpenSSL 0.9.7.

MirOS BSD #10-current      2016-10-06                          10

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