aboutsummaryrefslogtreecommitdiff
path: root/openssl/doc/apps/enc.pod
diff options
context:
space:
mode:
Diffstat (limited to 'openssl/doc/apps/enc.pod')
-rw-r--r--openssl/doc/apps/enc.pod279
1 files changed, 279 insertions, 0 deletions
diff --git a/openssl/doc/apps/enc.pod b/openssl/doc/apps/enc.pod
new file mode 100644
index 000000000..4391c9336
--- /dev/null
+++ b/openssl/doc/apps/enc.pod
@@ -0,0 +1,279 @@
+=pod
+
+=head1 NAME
+
+enc - symmetric cipher routines
+
+=head1 SYNOPSIS
+
+B<openssl enc -ciphername>
+[B<-in filename>]
+[B<-out filename>]
+[B<-pass arg>]
+[B<-e>]
+[B<-d>]
+[B<-a>]
+[B<-A>]
+[B<-k password>]
+[B<-kfile filename>]
+[B<-K key>]
+[B<-iv IV>]
+[B<-p>]
+[B<-P>]
+[B<-bufsize number>]
+[B<-nopad>]
+[B<-debug>]
+
+=head1 DESCRIPTION
+
+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.
+
+=head1 OPTIONS
+
+=over 4
+
+=item B<-in filename>
+
+the input filename, standard input by default.
+
+=item B<-out filename>
+
+the output filename, standard output by default.
+
+=item B<-pass arg>
+
+the password source. For more information about the format of B<arg>
+see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)|openssl(1)>.
+
+=item B<-salt>
+
+use a salt in the key derivation routines. This option should B<ALWAYS>
+be used unless compatibility with previous versions of OpenSSL or SSLeay
+is required. This option is only present on OpenSSL versions 0.9.5 or
+above.
+
+=item B<-nosalt>
+
+don't use a salt in the key derivation routines. This is the default for
+compatibility with previous versions of OpenSSL and SSLeay.
+
+=item B<-e>
+
+encrypt the input data: this is the default.
+
+=item B<-d>
+
+decrypt the input data.
+
+=item B<-a>
+
+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.
+
+=item B<-A>
+
+if the B<-a> option is set then base64 process the data on one line.
+
+=item B<-k password>
+
+the password to derive the key from. This is for compatibility with previous
+versions of OpenSSL. Superseded by the B<-pass> argument.
+
+=item B<-kfile filename>
+
+read the password to derive the key from the first line of B<filename>.
+This is for compatibility with previous versions of OpenSSL. Superseded by
+the B<-pass> argument.
+
+=item B<-S salt>
+
+the actual salt to use: this must be represented as a string comprised only
+of hex digits.
+
+=item B<-K key>
+
+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 B<-iv> option. When both a key and a password are specified, the
+key given with the B<-K> 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.
+
+=item B<-iv IV>
+
+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 B<-K> 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.
+
+=item B<-p>
+
+print out the key and IV used.
+
+=item B<-P>
+
+print out the key and IV used then immediately exit: don't do any encryption
+or decryption.
+
+=item B<-bufsize number>
+
+set the buffer size for I/O
+
+=item B<-nopad>
+
+disable standard block padding
+
+=item B<-debug>
+
+debug the BIOs used for I/O.
+
+=back
+
+=head1 NOTES
+
+The program can be called either as B<openssl ciphername> or
+B<openssl enc -ciphername>.
+
+A password will be prompted for to derive the key and IV if necessary.
+
+The B<-salt> option should B<ALWAYS> be used if the key is being derived
+from a password unless you want compatibility with previous versions of
+OpenSSL and SSLeay.
+
+Without the B<-salt> 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.
+
+=head1 SUPPORTED CIPHERS
+
+ 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
+
+ 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
+
+=head1 EXAMPLES
+
+Just base64 encode a binary file:
+
+ openssl base64 -in file.bin -out file.b64
+
+Decode the same file
+
+ 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
+
+=head1 BUGS
+
+The B<-A> option when used with large files doesn't work properly.
+
+There should be an option to allow an iteration count to be included.
+
+The B<enc> 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.
+
+=cut