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diff --git a/pipermail/pycrypto/2012q2/000603.html b/pipermail/pycrypto/2012q2/000603.html new file mode 100644 index 0000000..69a06f8 --- /dev/null +++ b/pipermail/pycrypto/2012q2/000603.html @@ -0,0 +1,102 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> +<HTML> + <HEAD> + <TITLE> [pycrypto] Typo or bug? + </TITLE> + <LINK REL="Index" HREF="index.html" > + <LINK REL="made" HREF="mailto:pycrypto%40lists.dlitz.net?Subject=Re%3A%20%5Bpycrypto%5D%20Typo%20or%20bug%3F&In-Reply-To=%3CCAGfyce3ST0n9M%2BwkccQM-H%2BQE9pWMOP19bmyQoSb-zTKJrLW5A%40mail.gmail.com%3E"> + <META NAME="robots" CONTENT="index,nofollow"> + <style type="text/css"> + pre { + white-space: pre-wrap; /* css-2.1, curent FF, Opera, Safari */ + } + </style> + <META http-equiv="Content-Type" content="text/html; charset=us-ascii"> + <LINK REL="Previous" HREF="000602.html"> + <LINK REL="Next" HREF="000604.html"> + </HEAD> + <BODY BGCOLOR="#ffffff"> + <H1>[pycrypto] Typo or bug?</H1> + <B>Legrandin</B> + <A HREF="mailto:pycrypto%40lists.dlitz.net?Subject=Re%3A%20%5Bpycrypto%5D%20Typo%20or%20bug%3F&In-Reply-To=%3CCAGfyce3ST0n9M%2BwkccQM-H%2BQE9pWMOP19bmyQoSb-zTKJrLW5A%40mail.gmail.com%3E" + TITLE="[pycrypto] Typo or bug?">gooksankoo at hoiptorrow.mailexpire.com + </A><BR> + <I>Tue Jun 26 07:31:15 EDT 2012</I> + <P><UL> + <LI>Previous message: <A HREF="000602.html">[pycrypto] Typo or bug? +</A></li> + <LI>Next message: <A HREF="000604.html">[pycrypto] Typo or bug? +</A></li> + <LI> <B>Messages sorted by:</B> + <a href="date.html#603">[ date ]</a> + <a href="thread.html#603">[ thread ]</a> + <a href="subject.html#603">[ subject ]</a> + <a href="author.html#603">[ author ]</a> + </LI> + </UL> + <HR> +<!--beginarticle--> +<PRE>><i> +</I>><i> +</I>><i> I think I have it working.... +</I>><i> +</I>><i> myiv = "some Random string" # which is 16 bytes long.... +</I>><i> encobj = AES.new(secret, AES.MODE_CFB, myiv) +</I>><i> +</I>><i> Would someone help me understand what is happening here please? +</I>><i> +</I>><i> I'm guessing on both encode and decode the 'myiv' string should be +</I>><i> identical... +</I>><i> but I'm unsure? +</I>><i> +</I>><i> <A HREF="https://www.dlitz.net/software/pycrypto/api/current/Crypto.Cipher.AES-module.html#new">https://www.dlitz.net/software/pycrypto/api/current/Crypto.Cipher.AES-module.html#new</A> +</I>><i> shows it in use, but with no explanation? +</I>><i> +</I>><i> +</I>Choice of the IV is critical for security. +For CFB, the combination IV and key must be use only with one message, and +never occur again. +That is explained here: + +<A HREF="https://www.dlitz.net/software/pycrypto/api/current/Crypto.Cipher.blockalgo-module.html#MODE_CFB">https://www.dlitz.net/software/pycrypto/api/current/Crypto.Cipher.blockalgo-module.html#MODE_CFB</A> + +IV needs indeed to be share by the party encrypting and by the party +decrypting the message. + +Up to pycrypto 2.5, when no iv was provided to new() a string of zeroes was +automatically used. +Depending on your application, that may or may not be a problem. It is +wiser to always make iv explicit. +-------------- next part -------------- +An HTML attachment was scrubbed... +URL: <<A HREF="http://lists.dlitz.net/pipermail/pycrypto/attachments/20120626/e1bf90e4/attachment.html">http://lists.dlitz.net/pipermail/pycrypto/attachments/20120626/e1bf90e4/attachment.html</A>> +</PRE> + + + + + + + + + +<!--endarticle--> + <HR> + <P><UL> + <!--threads--> + <LI>Previous message: <A HREF="000602.html">[pycrypto] Typo or bug? +</A></li> + <LI>Next message: <A HREF="000604.html">[pycrypto] Typo or bug? +</A></li> + <LI> <B>Messages sorted by:</B> + <a href="date.html#603">[ date ]</a> + <a href="thread.html#603">[ thread ]</a> + <a href="subject.html#603">[ subject ]</a> + <a href="author.html#603">[ author ]</a> + </LI> + </UL> + +<hr> +<a href="http://lists.dlitz.net/cgi-bin/mailman/listinfo/pycrypto">More information about the pycrypto +mailing list</a><br> +</body></html> |