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Add comments about requiring keysize <= 2*SHA1_HASH_SIZE
author Matt Johnston <matt@ucc.asn.au>
date Sun, 04 Feb 2007 10:31:48 +0000
parents 1b9e69c058d2
children 0cbe8f6dbf9e
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Tech Note 0005
Minimizing Code Space
Tom St Denis

Introduction
------------

Tweaking...

You can disable whole classes of algorithms on the command line with the LTC_NO_* defines.  From there you can manually turn on what you want to enable.  

The following build with GCC 3.4.3 on an AMD64 box gets you AES, CTR mode, SHA-256, HMAC, Yarrow, full RSA PKCS #1, PKCS #5, ASN.1 DER and MPI in 
roughly 80KB of code.

CFLAGS="-DSC_RSA_1 -DLTC_NO_CIPHERS -DLTC_NO_HASHES -DLTC_NO_PRNGS -DLTC_NO_MACS -DLTC_NO_MODES -DLTC_NO_PK -DRIJNDAEL -DCTR -DSHA256 \
-DHMAC -DYARROW -DMRSA -DMPI -Os -fomit-frame-pointer" make IGNORE_SPEED=1

Neato eh?