Hacking - The Art of Exploitation, 2nd Edition

Countermeasures 387 matrix@loki /hacking $ for i in seq 1 50; do ./notesearch $(perl -e "print 'AAAA'x$i"); if [ $? == 139 ]; th ...

388 0x600 Without the jmp esp instruction at a predictable address, there is no easy way to bounce off of linux-gate. Can you th ...

Countermeasures 389 manual page for execve() for detailed information about the replacement of the current process.) It seems li ...

390 0x600 The first result looks very promising, but further attempts show that there is some degree of randomization happening ...

Countermeasures 391 for(i=0; i < 90; i+=4) // Fill buffer with return address. *((unsigned int *)(buffer+i)) = ret; memset(bu ...

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0x700 CRYPTOLOGY Cryptology is defined as the study of cryptography or cryptanalysis. Cryptography is simply the process of com- ...

394 0x700 encryption, credit card transactions at popular websites would be either very inconvenient or insecure. All of this pr ...

Cryptology 395 0x712 One-Time Pads............................................................................ One example of an ...

396 0x700 through the incorrect filter, its polarization will be randomly modified. This means that any eavesdropping attempt to ...

Cryptology 397 0x720 Algorithmic Run Time Algorithmic run time is a bit different from the run time of a program. Since an algor ...

398 0x700 This means that, in general, the growth rate of the time complexity of an algorithm with respect to input size is more ...

Cryptology 399 and diffusion. Confusion refers to methods used to hide relationships between the plaintext, the ciphertext, and ...

400 0x700 Without some way to manipulate the odds of the superposition states, the same effect could be achieved by just guessin ...

Cryptology 401 the greatest common divisor (GCD) of two numbers. The larger of the two numbers is divided by the smaller number, ...

402 0x700 With a little bit of basic algebra, the terms can be moved around for each line so the remainder (shown in bold) is by ...

Cryptology 403 The numbers in the previous example were chosen for their relevance to RSA. Assuming the values for P and Q are 1 ...

404 0x700 Since this is all done modulo N, the following is also true, due to the way multiplication works in modulus arithmetic ...

Cryptology 405 The algorithm is actually quite simple. Take a number, N, to factor. Choose a value, A, that is less than N. This ...

406 0x700 0x750 Hybrid Ciphers A hybrid cryptosystem gets the best of both worlds. An asymmetric cipher is used to exchange a ra ...