From: Matt Birkholz Date: Fri, 3 Nov 2017 08:13:47 +0000 (-0700) Subject: Merge branch 'master' into pucked. X-Git-Tag: mit-scheme-pucked-9.2.12~44 X-Git-Url: https://birchwood-abbey.net/git?a=commitdiff_plain;h=e8499b5ec3b5d73fd836569ea2e872d50da38808;p=mit-scheme.git Merge branch 'master' into pucked. --- e8499b5ec3b5d73fd836569ea2e872d50da38808 diff --cc src/blowfish/Makefile.am index afedc8969,e0b129c29..357319a53 --- a/src/blowfish/Makefile.am +++ b/src/blowfish/Makefile.am @@@ -42,8 -41,8 +42,8 @@@ binaries = @MIT_SCHEME_BCIs@ @MIT_SCHEM scmlib_sub_DATA = $(sources) $(binaries) scmlib_sub_DATA += make.scm @MIT_SCHEME_PKD@ - #scminfo_DATA = blowfish.info - #AM_MAKEINFOHTMLFLAGS = --no-split -info_TEXINFOS = mit-scheme-blowfish.texi ++scminfo_DATA = blowfish.info + AM_MAKEINFOHTMLFLAGS = --no-split AM_CPPFLAGS = -I@MIT_SCHEME_INCLUDEDIR@ AM_CFLAGS = @MIT_CFLAGS@ diff --cc src/blowfish/blowfish.texi index 000000000,2fbf3b284..8e15b2eb9 mode 000000,100644..100644 --- a/src/blowfish/blowfish.texi +++ b/src/blowfish/blowfish.texi @@@ -1,0 -1,723 +1,741 @@@ + \input texinfo @c -*-texinfo-*- + @comment %**start of header -@setfilename mit-scheme-blowfish.info ++@setfilename blowfish.info + @include version.texi -@set SCMVERS 9.2.1 -@settitle MIT/GNU Scheme Blowfish Plugin Manual ++@set SCMVERS 9.2.7 ++@settitle Blowfish Plugin Manual + @comment %**end of header + ++@ifhtml ++@macro bref {name} ++@ref{\name\,,@code{\name\}} ++@end macro ++@end ifhtml ++@ifinfo ++@macro bref {name} ++\name\ ++@end macro ++@end ifinfo ++@ifnothtml ++@ifnotinfo ++@macro bref {name} ++@code{\name\} ++@end macro ++@end ifnotinfo ++@end ifnothtml ++ + @copying -This manual documents MIT/GNU Scheme Blowfish @value{VERSION}. ++This manual documents MIT/GNU Scheme Pucked Blowfish @value{VERSION}. + + Copyright @copyright{} 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, + 2015, 2016, 2017 Matthew Birkholz + + @quotation + Permission is granted to copy, distribute and/or modify this document + under the terms of the GNU Free Documentation License, Version 1.2 or + any later version published by the Free Software Foundation; with no + Invariant Sections, with no Front-Cover Texts and no Back-Cover Texts. + A copy of the license is included in the section entitled ``GNU Free + Documentation License.'' + @end quotation + @end copying + + @dircategory Programming Languages + @direntry -* Blowfish: (mit-scheme-blowfish). ++* Blowfish: (mit-scheme-pucked/blowfish). + Blowfish plugin. + @end direntry + + @titlepage -@title MIT/GNU Scheme Blowfish Plugin Manual ++@title Blowfish Plugin Manual + @subtitle a Blowfish block cipher plugin (version @value{VERSION}) -@subtitle for MIT/GNU Scheme version @value{SCMVERS} ++@subtitle for MIT/GNU Scheme Pucked version @value{SCMVERS} + @subtitle @value{UPDATED} + @author by Matt Birkholz + @page + @vskip 0pt plus 1filll + @insertcopying + @end titlepage + + @ifnottex + @node Top + @top Blowfish Plugin Manual + + @insertcopying + @end ifnottex + + @menu + * Introduction:: + * Procedures:: + * DES Modes:: + * GNU Free Documentation License:: + @end menu + + @node Introduction + @chapter Introduction + + This plugin is a dynamically loadable wrapper of the Blowfish block + cipher C API as implemented by libssl (OpenSSL). + + The cipher operates on 64 bit (8 byte) blocks of data and uses a + variable size key. Keys with 128 bits (16 bytes) are considered good + for strong encryption. Blowfish can be used in the same modes as DES + and is currently one of the faster block ciphers. It is quite a bit + faster than DES, and much faster than IDEA or RC2. + + The plugin includes a Scheme procedure to feed bytes from a binary + input port to the library, and write the encrypted bytes to a binary + output port. + + @node Procedures + @chapter Procedures + + Blowfish consists of a key setup phase and the actual encryption or + decryption phase. + + @deffn Procedure blowfish-set-key bytes + Generate a Blowfish key from @var{bytes}, which must be 72 bytes or -less in length. For text keys (strings), apply @code{md5} to the ++less in length. For text keys (strings), apply @bref{md5} to the + string, and use the digest for @var{bytes}. + @end deffn + + @deffn Procedure blowfish-ecb input output key encyrpt? + Apply Blowfish in Electronic Code Book mode. + @var{Input} is an 8-byte byte vector. + @var{Output} is an 8-byte byte vector. + @var{Key} is a Blowfish key. + @var{Encrypt?} specifies whether to encrypt (when @code{#t}) or decrypt + (when @code{#f}). + @end deffn + + The mode functions below all operate on variable length data. They + all take an initialization vector which needs to be passed along into + the next call of the same function for the same message. The vector + may be initialized with anything, but the recipient needs to know what + it was initialized with, or it won't be able to decrypt. Some + programs and protocols simplify this, like SSH, where the vector is -simply initialized to zero. @code{Blowfish-cbc} operates on data that -is a multiple of 8 bytes long, while @code{blowfish-cfb64} and -@code{blowfish-ofb64} are used to encrypt any number of bytes. The ++simply initialized to zero. @bref{Blowfish-cbc} operates on data that ++is a multiple of 8 bytes long, while @bref{blowfish-cfb64} and ++@bref{blowfish-ofb64} are used to encrypt any number of bytes. The + purpose of the latter two is to simulate stream ciphers, and + therefore, they have a parameter @code{num}, the current offset in the + initialization vector, which should start at zero and be stored + between calls. + + @deffn Procedure blowfish-cbc input output key init encrypt? + Apply Blowfish in Cipher Block Chaining mode. + @var{Input} is a multiple of 8 bytes. + @var{Output} is the same number of bytes as in Input. + @var{Key} is a Blowfish key. + @var{Init} is an 8 byte initialization vector; + it is modified after each call. + The value from any call may be passed in to a later call. + @var{Encrypt?} specifies whether to encrypt (when @code{#t}) or decrypt + (when @code{#f}). + @end deffn + + @deffn Procedure blowfish-cfb64 input istart iend output ostart key init num encrypt? + Apply Blowfish in Cipher Feed-Back mode. + @var{Istart} and @var{Iend} specify a range of bytes in @var{Input}. + @var{Ostart} specifies the first byte to write in @var{Output}. + @var{Key} is a Blowfish key. + @var{Init} is an 8 byte initialization vector; + it is modified after each call. + The value from any call may be passed in to a later call. + The initial value must be unique for each message/key pair. + @var{Num} is an integer from 0 to 7 inclusive, the low 3 bits of the + number of bytes that have previously been processed in this stream. + @var{Encrypt?} specifies whether to encrypt (when @code{#t}) or decrypt + (when @code{#f}). + The returned value is the new value of Num. + @end deffn + + @deffn Procedure blowfish-ofb64 input istart iend output ostart key init num + Apply Blowfish in Output Feed-Back mode. + @var{Istart} and @var{Iend} specify a range of bytes in @var{Input}. + @var{Ostart} specifies the first byte to write in @var{Output}. + @var{Key} is a Blowfish key. + @var{Init} is an 8 byte initialization vector; + it is modified after each call. + The value from any call may be passed in to a later call. + The initial value must be unique for each message/key pair. + @var{Num} is an integer from 0 to 7 inclusive, the low 3 bits of the + number of bytes that have previously been processed in this stream. + The returned value is the new value of Num. + @end deffn + + Two convenience procedures are also provided. + + @deffn Procedure blowfish-encrypt-port input output key init encrypt? + Reads bytes from @var{input}, which should be in blocking mode, until -the end. Feeds the bytes to @code{blowfish-cfb64} and writes the ++the end. Feeds the bytes to @bref{blowfish-cfb64} and writes the + resulting, encrypted bytes to @var{output}. @var{Key} and -@var{init} are passed to @code{blowfish-cfb64} (which modifies ++@var{init} are passed to @bref{blowfish-cfb64} (which modifies + the latter). + @var{Encrypt?} specifies whether to encrypt (when @code{#t}) or decrypt + (when @code{#f}). + @end deffn + + @deffn Procedure compute-blowfish-init-vector + Returns a new initialization vector that includes a timestamp with a + resolution of milliseconds, plus 20 random bits. This should make it + very likely unique. + @end deffn + + The Blowfish cipher was invented and described by Counterpane (see + @url{http://www.counterpane.com/blowfish.html}). Most of this manual + was adapted from the OpenSSL manual pages. + + @node DES Modes + @chapter DES Modes + + This chapter was written in large parts by Eric Young in his original + documentation for SSLeay, the predecessor of OpenSSL. In turn, he + attributed it to: + + @smallexample + 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 + @end smallexample + + @section Electronic Codebook Mode (ECB) + + 64 bits are enciphered at a time. + + The order of the blocks can be rearranged without detection. + + The same plain text block always produces the same cipher text block + (for the same key) making it vulnerable to a dictionary attack. + + An error will only affect one cipher text block. + + @section Cipher Block Chaining Mode (CBC) + + A multiple of 64 bits are enciphered at a time. + + The CBC mode produces the same cipher text whenever the same plain text + is encrypted using the same key and starting variable. + + The chaining operation makes the cipher text blocks dependent on the + current and all preceding plain text blocks and therefore blocks can + not be rearranged. + + The use of different starting variables prevents the same plain text + enciphering to the same cipher text. + + An error will affect the current and the following cipher text blocks. + + @section Cipher Feedback Mode (CFB) + + Any number of bits, j, up to 64, are enciphered at a time. + + The CFB mode produces the same cipher text whenever the same plain text + is encrypted using the same key and starting variable. + + The chaining operation makes the cipher text variables dependent on + the current and all preceding variables and therefore j-bit variables + are chained together and can not be rearranged. + + The use of different starting variables prevents the same plain text + enciphering to the same cipher text. + + The strength of the CFB mode depends on the size of k (maximal if j + = k). In my implementation this is always the case. + + Selection of a small value for j will require more cycles through the + encipherment algorithm per unit of plain text and thus cause greater + processing overheads. + + Only multiples of j bits can be enciphered. + + An error will affect the current and the following cipher text + variables. + + @section Output Feedback Mode (OFB) + + Any number of bits, j, up to 64, are enciphered at a time. + + The OFB mode produces the same cipher text whenever the same plain text + enciphered using the same key and starting variable. More over, in + the OFB mode the same key stream is produced when the same key and + start variable are used. Consequently, for security reasons a + specific start variable should be used only once for a given key. + + The absence of chaining makes the OFB more vulnerable to specific + attacks. + + The use of different start variables values prevents the same + plain text enciphering to the same cipher text, by producing different + key streams. + + Selection of a small value for j will require more cycles through the + encipherment algorithm per unit of plain text and thus cause greater + processing overheads. + + Only multiples of j bits can be enciphered. + + OFB mode of operation does not extend cipher text errors in the + resultant plain text output. Every bit error in the cipher text causes + only one bit to be in error in the deciphered plain text. + + OFB mode is not self-synchronizing. If the two operations of + encipherment and decipherment get out of synchronism, the system + needs to be re-initialized. + + 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 + susceptible to a 'known plain text' attack. + + @node GNU Free Documentation License + @appendix GNU Free Documentation License + + @cindex FDL, GNU Free Documentation License + @center Version 1.2, November 2002 + + @display + Copyright @copyright{} 2000,2001,2002 Free Software Foundation, Inc. + 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA + + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + @end display + + @enumerate 0 + @item + PREAMBLE + + The purpose of this License is to make a manual, textbook, or other + functional and useful document @dfn{free} in the sense of freedom: to + assure everyone the effective freedom to copy and redistribute it, + with or without modifying it, either commercially or noncommercially. + Secondarily, this License preserves for the author and publisher a way + to get credit for their work, while not being considered responsible + for modifications made by others. + + This License is a kind of ``copyleft'', which means that derivative + works of the document must themselves be free in the same sense. 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If the Document does not specify a version + number of this License, you may choose any version ever published (not + as a draft) by the Free Software Foundation. + @end enumerate + + @page + @appendixsec ADDENDUM: How to use this License for your documents + + To use this License in a document you have written, include a copy of + the License in the document and put the following copyright and + license notices just after the title page: + + @smallexample + @group + Copyright (C) @var{year} @var{your name}. + Permission is granted to copy, distribute and/or modify this document + under the terms of the GNU Free Documentation License, Version 1.2 + or any later version published by the Free Software Foundation; + with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. + A copy of the license is included in the section entitled ``GNU + Free Documentation License''. + @end group + @end smallexample + + If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, + replace the ``with...Texts.'' line with this: + + @smallexample + @group + with the Invariant Sections being @var{list their titles}, with + the Front-Cover Texts being @var{list}, and with the Back-Cover Texts + being @var{list}. + @end group + @end smallexample + + If you have Invariant Sections without Cover Texts, or some other + combination of the three, merge those two alternatives to suit the + situation. + + If your document contains nontrivial examples of program code, we + recommend releasing these examples in parallel under your choice of + free software license, such as the GNU General Public License, + to permit their use in free software. + + @bye