Lines Matching refs:Entropy
549 total amount of entropy in N bits is $N \cdot -log_2\left ({1 \over 2} + \vert \gamma \vert \right)$. So if $\gamma$
550 were $0.25$ (a severe bias) a 256-bit string would have about 106 bits of entropy whereas a 128-bit string would have
551 only 53 bits of entropy.
2672 entropy. Ideally you'd have some OS level source to tap like in UNIX. To add entropy to the PRNG call:
2679 Which returns {\bf CRYPT\_OK} if the entropy was accepted. Once you think you have enough entropy you call another
2680 function to put the entropy into action.
2714 be that much entropy available. To import a state to seed a PRNG call the following function.
2734 \item Gather entropy from your sources for a given period of time or number of events.
2735 \item Start, use your entropy via add\_entropy and ready the PRNG yourself.
2744 Note that even if you have a state to import it is important to add new entropy to the state. However,
2758 It is possible to be adding entropy and reading from a PRNG at the same time. For example, if you first seed the PRNG
2759 and call ready() you can now read from it. You can also keep adding new entropy to it. The new entropy will not be used
2761 checking is guaranteed to see if the entropy is sufficient, or if the PRNG is even in a ready state before reading.
2765 the entropy added is not random.
2779 /* add entropy */
2861 Yarrow is fast PRNG meant to collect an unspecified amount of entropy from sources
2879 Fortuna is more secure than Yarrow in the sense that attackers who learn parts of the entropy being
2883 recover from that problem until new entropy is added to the pool and put to use through the ready() function.
2906 Unlike Yarrow and Fortuna, all of the entropy (and hence security) of this algorithm rests in the data
2934 printf("RC4 add entropy error: %s\n", error_to_string(err));
2960 PRNG. Computers are deterministic that try hard not to stray from pre--determined paths. This makes gathering entropy needed to seed a PRNG
2975 clock drift method that is also somewhat popular but gives bits of lower entropy. The \textit{callback} parameter is a pointer to a function that returns void. It is
2986 This will try to initialize the prng with a state of at least \textit{bits} of entropy. The \textit{callback} parameter works much like
4928 access source of entropy for any application on a UNIX (and the like) or Windows computer.
4931 entropy. This manual is not designed to be a text on cryptography. I would just like to highlight that when you design
4932 a cryptosystem make sure the first problem you solve is getting a fresh source of entropy.
5876 /** Add entropy to the PRNG
5877 @param in The entropy
5878 @param inlen Length of the entropy (octets)
5944 Initialize the PRNG and make it ready to accept entropy.
5946 \subsection{Entropy Addition}
5947 Add entropy to the PRNG state. The exact behaviour of this function depends on the particulars of the PRNG.
5950 This function makes the PRNG ready to read from by processing the entropy added. The behaviour of this function depends
5962 but should at least maintain the same level of state entropy.
