Re: avr-crypto-lib

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From: bg <[email protected]>
To: =?UTF-8?B?UGF3ZcWCIFNp?= <[email protected]>,
 =?UTF-8?Q?BERTRAND_Jo=c3=abl?= <[email protected]>
Cc: AVR GCC List <[email protected]>
Message-ID: <[email protected]>
Subject: Re: avr-crypto-lib
References: <[email protected]>
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>> RSA doesn't run as expected. With expopent=3D3 and length=3D512, progr=
am
>> doesn't crash but after four hours (@ 16 MHz on simavr), gdb shows tha=
t
>> program stays in RSA subroutines and doesn't return to main routine.
>> Something is probably broken somewhere.

1) Sorry for the delayed reply.

2) I'm somewhat lacking the time to improve and document avr-crypto-lib (=
this also caused item 1)

3) RSA was newer really stable, or of useable speed (even with 1024 bit k=
eys). Also the current implementation is lacking some important optimizat=
ions.

4) I used the VLA additions of C99 to avoid issues with heap allocation, =
but they bring some problems of their own.

5) You may find https://munacl.cryptojedi.org/atmega.shtml helpful.

I hope to find some spare time to get some stuff better documented and im=
proved (or remove what can't be fixed).

For short: I doubt that RSA on an AVR could be brought to a productive us=
e (maybe except for some cases where you are willing to wait minutes).

Best regards,
~  bg

--=20
bg nerilex
Daniel Otte
E-Mail: [email protected]
XMPP/Jabber: [email protected]
Matrix: @bg:nerilex.org
Mastodon: https://chaos.social/@bg
Phone: +49-152-03012876
Fingerprint: CB4E 915F ACAD EEC2 0D34  D266 2978 788D 0DB2 E18E



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