Fix for AIX.

[oweals/openssl.git] / doc / crypto / des_modes.pod

diff --git a/doc/crypto/des_modes.pod b/doc/crypto/des_modes.pod
index 096a77f4a37ad24a2d2f2ddbada88d734dff099c..36b77c454d302b35343ca06ee3c8bded4a021414 100644 (file)
--- a/doc/crypto/des_modes.pod
+++ b/doc/crypto/des_modes.pod
@@ -2,20 +2,13 @@
 
 =head1 NAME
 
-Modes of DES and other crypto algorithms of OpenSSL
+Modes of DES - the variants of DES and other crypto algorithms of OpenSSL
 
 =head1 DESCRIPTION
 
-Several crypto algorithms fo OpenSSL can be used in a number of modes.  The
-following text has been written in large parts by Eric Young in his original
-documentation for SSLeay, the predecessor of OpenSSL.  In turn, he attributed
-it to:
-
-       AS 2805.5.2
-       Australian Standard
-       Electronic funds transfer - Requirements for interfaces,
-       Part 5.2: Modes of operation for an n-bit block cipher algorithm
-       Appendix A
+Several crypto algorithms for OpenSSL can be used in a number of modes.  Those
+are used for using block ciphers in a way similar to stream ciphers, among
+other things.
 
 =head1 OVERVIEW
 
@@ -47,6 +40,8 @@ An error will only affect one ciphertext block.
 =head2 Cipher Block Chaining Mode (CBC)
 
 Normally, this is found as the function I<algorithm>_cbc_encrypt().
+Be aware that des_cbc_encrypt() is not really DES CBC (it does
+not update the IV); use des_ncbc_encrypt() instead.
 
 =over 2
 
@@ -170,13 +165,13 @@ only one bit to be in error in the deciphered plaintext.
 
 =item *
 
-OFB mode is not self-synchronising.  If the two operation of
+OFB mode is not self-synchronizing.  If the two operation of
 encipherment and decipherment get out of synchronism, the system needs
-to be re-initialised.
+to be re-initialized.
 
 =item *
 
-Each re-initialisation should use a value of the start variable
+Each re-initialization should use a value of the start variable
 different from the start variable values used before with the same
 key.  The reason for this is that an identical bit stream would be
 produced each time from the same parameters.  This would be
@@ -237,7 +232,22 @@ the same restrictions as for triple ecb mode.
 
 =back
 
+=head1 NOTES
+
+This text was been written in large parts by Eric Young in his original
+documentation for SSLeay, the predecessor of OpenSSL.  In turn, he attributed
+it to:
+
+       AS 2805.5.2
+       Australian Standard
+       Electronic funds transfer - Requirements for interfaces,
+       Part 5.2: Modes of operation for an n-bit block cipher algorithm
+       Appendix A
+
 =head1 SEE ALSO
 
 L<blowfish(3)|blowfish(3)>, L<des(3)|des(3)>, L<idea(3)|idea(3)>,
 L<rc2(3)|rc2(3)>
+
+=cut
+