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author | Rich Salz <rsalz@openssl.org> | 2016-10-26 13:56:48 -0400 |
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committer | Rich Salz <rsalz@openssl.org> | 2016-10-26 13:59:52 -0400 |
commit | 99d63d4662e16afbeff49f29b48f1c87d5558ed0 (patch) | |
tree | 6512ff02cd93985526080f05ab2b5408235b19a9 /doc/man3/BF_encrypt.pod | |
parent | 4f3015bb30b7d95bb97408776b70e6a35fb91e8a (diff) |
Move manpages to man[1357] structure.
Move manpages to manX directories
Add Windows/VMS install fix from Richard Levitte
Update README
Fix typo's
Remove some duplicates
Reviewed-by: Richard Levitte <levitte@openssl.org>
Diffstat (limited to 'doc/man3/BF_encrypt.pod')
-rw-r--r-- | doc/man3/BF_encrypt.pod | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/doc/man3/BF_encrypt.pod b/doc/man3/BF_encrypt.pod new file mode 100644 index 0000000000..0401e90a20 --- /dev/null +++ b/doc/man3/BF_encrypt.pod @@ -0,0 +1,117 @@ +=pod + +=head1 NAME + +BF_set_key, BF_encrypt, BF_decrypt, BF_ecb_encrypt, BF_cbc_encrypt, +BF_cfb64_encrypt, BF_ofb64_encrypt, BF_options - Blowfish encryption + +=head1 SYNOPSIS + + #include <openssl/blowfish.h> + + void BF_set_key(BF_KEY *key, int len, const unsigned char *data); + + void BF_ecb_encrypt(const unsigned char *in, unsigned char *out, + BF_KEY *key, int enc); + void BF_cbc_encrypt(const unsigned char *in, unsigned char *out, + long length, BF_KEY *schedule, unsigned char *ivec, int enc); + void BF_cfb64_encrypt(const unsigned char *in, unsigned char *out, + long length, BF_KEY *schedule, unsigned char *ivec, int *num, + int enc); + void BF_ofb64_encrypt(const unsigned char *in, unsigned char *out, + long length, BF_KEY *schedule, unsigned char *ivec, int *num); + const char *BF_options(void); + + void BF_encrypt(BF_LONG *data, const BF_KEY *key); + void BF_decrypt(BF_LONG *data, const BF_KEY *key); + +=head1 DESCRIPTION + +This library implements the Blowfish cipher, which was invented and described +by Counterpane (see http://www.counterpane.com/blowfish.html ). + +Blowfish is a block cipher that operates on 64 bit (8 byte) blocks of data. +It uses a variable size key, but typically, 128 bit (16 byte) keys are +considered good for strong encryption. Blowfish can be used in the same +modes as DES (see L<des_modes(7)>). Blowfish is currently one +of the faster block ciphers. It is quite a bit faster than DES, and much +faster than IDEA or RC2. + +Blowfish consists of a key setup phase and the actual encryption or decryption +phase. + +BF_set_key() sets up the B<BF_KEY> B<key> using the B<len> bytes long key +at B<data>. + +BF_ecb_encrypt() is the basic Blowfish encryption and decryption function. +It encrypts or decrypts the first 64 bits of B<in> using the key B<key>, +putting the result in B<out>. B<enc> decides if encryption (B<BF_ENCRYPT>) +or decryption (B<BF_DECRYPT>) shall be performed. The vector pointed at by +B<in> and B<out> must be 64 bits in length, no less. If they are larger, +everything after the first 64 bits is ignored. + +The mode functions BF_cbc_encrypt(), BF_cfb64_encrypt() and BF_ofb64_encrypt() +all operate on variable length data. They all take an initialization vector +B<ivec> which needs to be passed along into the next call of the same function +for the same message. B<ivec> 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 +B<ivec> is simply initialized to zero. +BF_cbc_encrypt() operates on data that is a multiple of 8 bytes long, while +BF_cfb64_encrypt() and BF_ofb64_encrypt() are used to encrypt an variable +number of bytes (the amount does not have to be an exact multiple of 8). The +purpose of the latter two is to simulate stream ciphers, and therefore, they +need the parameter B<num>, which is a pointer to an integer where the current +offset in B<ivec> is stored between calls. This integer must be initialized +to zero when B<ivec> is initialized. + +BF_cbc_encrypt() is the Cipher Block Chaining function for Blowfish. It +encrypts or decrypts the 64 bits chunks of B<in> using the key B<schedule>, +putting the result in B<out>. B<enc> decides if encryption (BF_ENCRYPT) or +decryption (BF_DECRYPT) shall be performed. B<ivec> must point at an 8 byte +long initialization vector. + +BF_cfb64_encrypt() is the CFB mode for Blowfish with 64 bit feedback. +It encrypts or decrypts the bytes in B<in> using the key B<schedule>, +putting the result in B<out>. B<enc> decides if encryption (B<BF_ENCRYPT>) +or decryption (B<BF_DECRYPT>) shall be performed. B<ivec> must point at an +8 byte long initialization vector. B<num> must point at an integer which must +be initially zero. + +BF_ofb64_encrypt() is the OFB mode for Blowfish with 64 bit feedback. +It uses the same parameters as BF_cfb64_encrypt(), which must be initialized +the same way. + +BF_encrypt() and BF_decrypt() are the lowest level functions for Blowfish +encryption. They encrypt/decrypt the first 64 bits of the vector pointed by +B<data>, using the key B<key>. These functions should not be used unless you +implement 'modes' of Blowfish. The alternative is to use BF_ecb_encrypt(). +If you still want to use these functions, you should be aware that they take +each 32-bit chunk in host-byte order, which is little-endian on little-endian +platforms and big-endian on big-endian ones. + +=head1 RETURN VALUES + +None of the functions presented here return any value. + +=head1 NOTE + +Applications should use the higher level functions +L<EVP_EncryptInit(3)> etc. instead of calling these +functions directly. + +=head1 SEE ALSO + +L<EVP_EncryptInit(3)>, +L<des_modes(7)> + +=head1 COPYRIGHT + +Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved. + +Licensed under the OpenSSL license (the "License"). You may not use +this file except in compliance with the License. You can obtain a copy +in the file LICENSE in the source distribution or at +L<https://www.openssl.org/source/license.html>. + +=cut |