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rc4(3)
NAME
  rc4, RC4_set_key, RC4 - RC4 encryption

SYNOPSIS
  #include <openssl/rc4.h>

  void RC4_set_key(
	  RC4_KEY *key, int len, const unsigned char *data );

  void RC4(
	  RC4_KEY *key, unsigned long len, const unsigned char *indata,
  unsigned char *outdata );

DESCRIPTION
  This library implements the Alleged RC4 cipher, which is described in
  Applied Cryptography.	 It is believed to be compatible with
  <trademark>RC4</trademark>, a proprietary cipher of RSA Security Inc.

  RC4 is a stream cipher with variable key length.  Typically, 128 bit (16
  byte) keys are used for strong encryption, but shorter insecure key sizes
  have been widely used due to export restrictions.

  RC4 consists of a key setup phase and the actual encryption or decryption
  phase.

  The RC4_set_key() function sets up the RC4_KEY key using the len bytes long
  key at data.

  The RC4() function encrypts or decrypts the len bytes of data at indata
  using key and places the result at outdata.  Repeated RC4() calls with the
  same key yield a continuous key stream.

  Since RC4 is a stream cipher (the input is XORed with a pseudo-random key
  stream to produce the output), decryption uses the same function calls as
  encryption.

  Applications should use the higher level functions  instead of calling the
  RC4 functions directly. (See EVP_EncryptInit(3).)

NOTES
  Certain conditions have to be observed to securely use stream ciphers.  You
  cannot perform multiple encryptions using the same key stream.

RETURN VALUES
  The RC4_set_key() and RC4() functions do not return values.

HISTORY
  The RC4_set_key() and RC4() functions are available in all versions of
  SSLeay and OpenSSL.

SEE ALSO
  Functions: blowfish(3), des(3), rc2(3)

Index for Section 3

Alphabetical listing for R

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