Manual Pages for UNIX Operating System command usage for man enc

OpenSSL                                             ENC(1openssl)



NNNNAAAAMMMMEEEE
     enc - symmetric cipher routines

SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
     ooooppppeeeennnnssssssssllll eeeennnncccc ---ccciiiipppphhhheeeerrrrnnnnaaaammmmeeee [---iiinnnn ffffiiiilllleeeennnnaaaammmmeeee] [---ooouuuutttt ffffiiiilllleeeennnnaaaammmmeeee]
     [---pppaaaassssssss aaaarrrrgggg] [---eee] [---ddd] [---aaa] [---AAA] [---kkk ppppaaaasssssssswwwwoooorrrrdddd] [---kkkffffiiiilllleeee
     ffffiiiilllleeeennnnaaaammmmeeee] [---KKK kkkkeeeeyyyy] [---iiivvvv IIIIVVVV] [---ppp] [---PPP] [---bbbuuuuffffssssiiiizzzzeeee nnnnuuuummmmbbbbeeeerrrr]
     [---nnnooooppppaaaadddd] [---dddeeeebbbbuuuugggg]

DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
     The symmetric cipher commands allow data to be encrypted or
     decrypted using various block and stream ciphers using keys
     based on passwords or explicitly provided. Base64 encoding
     or decoding can also be performed either by itself or in
     addition to the encryption or decryption.

OOOOPPPPTTTTIIIIOOOONNNNSSSS
     -iiiinnnn ffffiiiilllleeeennnnaaaammmmeeee
         the input filename, standard input by default.

     -oooouuuutttt ffffiiiilllleeeennnnaaaammmmeeee
         the output filename, standard output by default.

     -ppppaaaassssssss aaaarrrrgggg
         the password source. For more information about the
         format of aaaarrrrgggg see the PPPPAAAASSSSSSSS PPPPHHHHRRRRAAAASSSSEEEE AAAARRRRGGGGUUUUMMMMEEEENNNNTTTTSSSS section in
         openssl(1).

     -ssssaaaalllltttt
         use a salt in the key derivation routines. This is the
         default.

     -nnnnoooossssaaaalllltttt
         don't use a salt in the key derivation routines. This
         option SSSSHHHHOOOOUUUULLLLDDDD NNNNOOOOTTTT be used except for test purposes or
         compatibility with ancient versions of OpenSSL and
         SSLeay.

     -eeee  encrypt the input data: this is the default.

     -dddd  decrypt the input data.

     -aaaa  base64 process the data. This means that if encryption
         is taking place the data is base64 encoded after
         encryption. If decryption is set then the input data is
         base64 decoded before being decrypted.

     -AAAA  if the ---aaa option is set then base64 process the data on
         one line.

     -kkkk ppppaaaasssssssswwwwoooorrrrdddd
         the password to derive the key from. This is for



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OpenSSL                                             ENC(1openssl)



         compatibility with previous versions of OpenSSL.
         Superseded by the ---pppaaaassssssss argument.

     -kkkkffffiiiilllleeee ffffiiiilllleeeennnnaaaammmmeeee
         read the password to derive the key from the first line
         of ffffiiiilllleeeennnnaaaammmmeeee.  This is for compatibility with previous
         versions of OpenSSL. Superseded by the ---pppaaaassssssss argument.

     -SSSS ssssaaaalllltttt
         the actual salt to use: this must be represented as a
         string comprised only of hex digits.

     -KKKK kkkkeeeeyyyy
         the actual key to use: this must be represented as a
         string comprised only of hex digits. If only the key is
         specified, the IV must additionally specified using the
         ---iiivvvv option. When both a key and a password are
         specified, the key given with the ---KKK option will be used
         and the IV generated from the password will be taken. It
         probably does not make much sense to specify both key
         and password.

     -iiiivvvv IIIIVVVV
         the actual IV to use: this must be represented as a
         string comprised only of hex digits. When only the key
         is specified using the ---KKK option, the IV must explicitly
         be defined. When a password is being specified using one
         of the other options, the IV is generated from this
         password.

     -pppp  print out the key and IV used.

     -PPPP  print out the key and IV used then immediately exit:
         don't do any encryption or decryption.

     -bbbbuuuuffffssssiiiizzzzeeee nnnnuuuummmmbbbbeeeerrrr
         set the buffer size for I/O

     -nnnnooooppppaaaadddd
         disable standard block padding

     -ddddeeeebbbbuuuugggg
         debug the BIOs used for I/O.

NNNNOOOOTTTTEEEESSSS
     The program can be called either as ooooppppeeeennnnssssssssllll cccciiiipppphhhheeeerrrrnnnnaaaammmmeeee or
     ooooppppeeeennnnssssssssllll eeeennnncccc ---ccciiiipppphhhheeeerrrrnnnnaaaammmmeeee.

     A password will be prompted for to derive the key and IV if
     necessary.





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OpenSSL                                             ENC(1openssl)



     The ---sssaaaalllltttt option should AAAALLLLWWWWAAAAYYYYSSSS be used if the key is being
     derived from a password unless you want compatibility with
     previous versions of OpenSSL and SSLeay.

     Without the ---sssaaaalllltttt option it is possible to perform efficient
     dictionary attacks on the password and to attack stream
     cipher encrypted data. The reason for this is that without
     the salt the same password always generates the same
     encryption key. When the salt is being used the first eight
     bytes of the encrypted data are reserved for the salt: it is
     generated at random when encrypting a file and read from the
     encrypted file when it is decrypted.

     Some of the ciphers do not have large keys and others have
     security implications if not used correctly. A beginner is
     advised to just use a strong block cipher in CBC mode such
     as bf or des3.

     All the block ciphers normally use PKCS#5 padding also known
     as standard block padding: this allows a rudimentary
     integrity or password check to be performed. However since
     the chance of random data passing the test is better than 1
     in 256 it isn't a very good test.

     If padding is disabled then the input data must be a
     multiple of the cipher block length.

     All RC2 ciphers have the same key and effective key length.

     Blowfish and RC5 algorithms use a 128 bit key.

SSSSUUUUPPPPPPPPOOOORRRRTTTTEEEEDDDD CCCCIIIIPPPPHHHHEEEERRRRSSSS
      base64             Base 64

      bf-cbc             Blowfish in CBC mode
      bf                 Alias for bf-cbc
      bf-cfb             Blowfish in CFB mode
      bf-ecb             Blowfish in ECB mode
      bf-ofb             Blowfish in OFB mode

      cast-cbc           CAST in CBC mode
      cast               Alias for cast-cbc
      cast5-cbc          CAST5 in CBC mode
      cast5-cfb          CAST5 in CFB mode
      cast5-ecb          CAST5 in ECB mode
      cast5-ofb          CAST5 in OFB mode

      des-cbc            DES in CBC mode
      des                Alias for des-cbc
      des-cfb            DES in CBC mode
      des-ofb            DES in OFB mode
      des-ecb            DES in ECB mode



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OpenSSL                                             ENC(1openssl)



      des-ede-cbc        Two key triple DES EDE in CBC mode
      des-ede            Two key triple DES EDE in ECB mode
      des-ede-cfb        Two key triple DES EDE in CFB mode
      des-ede-ofb        Two key triple DES EDE in OFB mode

      des-ede3-cbc       Three key triple DES EDE in CBC mode
      des-ede3           Three key triple DES EDE in ECB mode
      des3               Alias for des-ede3-cbc
      des-ede3-cfb       Three key triple DES EDE CFB mode
      des-ede3-ofb       Three key triple DES EDE in OFB mode

      desx               DESX algorithm.

      idea-cbc           IDEA algorithm in CBC mode
      idea               same as idea-cbc
      idea-cfb           IDEA in CFB mode
      idea-ecb           IDEA in ECB mode
      idea-ofb           IDEA in OFB mode

      rc2-cbc            128 bit RC2 in CBC mode
      rc2                Alias for rc2-cbc
      rc2-cfb            128 bit RC2 in CFB mode
      rc2-ecb            128 bit RC2 in ECB mode
      rc2-ofb            128 bit RC2 in OFB mode
      rc2-64-cbc         64 bit RC2 in CBC mode
      rc2-40-cbc         40 bit RC2 in CBC mode

      rc4                128 bit RC4
      rc4-64             64 bit RC4
      rc4-40             40 bit RC4

      rc5-cbc            RC5 cipher in CBC mode
      rc5                Alias for rc5-cbc
      rc5-cfb            RC5 cipher in CFB mode
      rc5-ecb            RC5 cipher in ECB mode
      rc5-ofb            RC5 cipher in OFB mode

      aes-[128|192|256]-cbc  128/192/256 bit AES in CBC mode
      aes-[128|192|256]      Alias for aes-[128|192|256]-cbc
      aes-[128|192|256]-cfb  128/192/256 bit AES in 128 bit CFB mode
      aes-[128|192|256]-cfb1 128/192/256 bit AES in 1 bit CFB mode
      aes-[128|192|256]-cfb8 128/192/256 bit AES in 8 bit CFB mode
      aes-[128|192|256]-ecb  128/192/256 bit AES in ECB mode
      aes-[128|192|256]-ofb  128/192/256 bit AES in OFB mode


EEEEXXXXAAAAMMMMPPPPLLLLEEEESSSS
     Just base64 encode a binary file:

      openssl base64 -in file.bin -out file.b64

     Decode the same file



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OpenSSL                                             ENC(1openssl)



      openssl base64 -d -in file.b64 -out file.bin

     Encrypt a file using triple DES in CBC mode using a prompted
     password:

      openssl des3 -salt -in file.txt -out file.des3

     Decrypt a file using a supplied password:

      openssl des3 -d -salt -in file.des3 -out file.txt -k mypassword

     Encrypt a file then base64 encode it (so it can be sent via
     mail for example) using Blowfish in CBC mode:

      openssl bf -a -salt -in file.txt -out file.bf

     Base64 decode a file then decrypt it:

      openssl bf -d -salt -a -in file.bf -out file.txt

     Decrypt some data using a supplied 40 bit RC4 key:

      openssl rc4-40 -in file.rc4 -out file.txt -K 0102030405


BBBBUUUUGGGGSSSS
     The ---AAA option when used with large files doesn't work
     properly.

     There should be an option to allow an iteration count to be
     included.

     The eeeennnncccc program only supports a fixed number of algorithms
     with certain parameters. So if, for example, you want to use
     RC2 with a 76 bit key or RC4 with an 84 bit key you can't
     use this program.



















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OpenSSL                                             ENC(1openssl)























































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