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| | CBofN - Glossary - X |
 | | XOR The exclusive-or function; given two Boolean inputs, the output of XOR is 1 if and only if the two inputs are different; otherwise, the output is 0. |
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http://mitpress.mit.edu/books/FLAOH/cbnhtml/glossary-X.html
(28 words)
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| | Glossary Search Results |
| | X Window System (X Windows) - A consortium-developed, open-standard, device-independent GUI system that is most commonly found on UNIX and Linux operating systems and invoked with the "startx" command. | | | The X Window System was initially developed in 1984 at MIT and called Project Athena. | | | For example (0 XOR 0) = 0, (0 XOR 1) = 1, (1 XOR 0) = 1, (1 XOR 1) = 0. |
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http://www.geek.com/glossary/glossary_search.cgi?x
(809 words)
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| | Quadibloc V |
| | The XOR of all the bytes at odd numbered positions in the key, where the first byte in the key is considered to be byte 1, and odd. | | | All intermediate results are used to XOR with subkey bytes, and the order is similar to that for the four-round version: first, an XOR is done to the first eight bytes in each of the eight rounds, then the next eight bytes in each of the eight rounds. | | | The subkey byte generated is the XOR of P and Q and an additional byte generated from the third string by the nonlinear shift register operation. |
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http://www.quadibloc.com/crypto/co040708.htm
(2768 words)
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| | X |
| | X is a powerful environment which supports many different applications, such as games, programming tools, graphics programs, text editors, etc. XFree86 is the version of X which runs on Linux, as well as other platforms. | | |
X Window System client libraries The X libraries are an interface between X client programs and the hardware-oriented X servers, and consist of routines to read input from the keyboard and pointer, draw on the screen, etc., in an abstract manner that is independent of the particular characteristics of the hardware. | | | The version of X used in Debian is derived from the version released by the XFree86 Project, Inc., and is thus often also referred to as "XFree86". |
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http://www.tldp.org/LDP/Linux-Dictionary/html/x.html
(12298 words)
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| | [No title] |
| | So that the output of this XOR would be a 0 with probability 1/2 and a 1 with probability 1/2. | | | There is no f(x) value that DOES NOT have a preimage x value -- A fxn is invertible IFF it it bijective (injective & surjective). | | | Practically, this means would have different inputs (plaintext & key) mapping to the same ciphertext output. |
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http://www.stanford.edu/~stinson/crypto/cs255/cs255_rev0.txt
(2489 words)
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| | An Introduction to Logic and Truth Tables |
| | The computer may need to know if x is greater than, less than, or equal to y. | | | For example, a computer program that calculates KU students GPAs might need to know if a particular GPA is less than 2.0 so that student can be placed on academic probation (heaven forbid). | | | There are two methods to evaluate the expression, both involve creating a complete truth table. |
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http://people.eecs.ku.edu/~eecs128/site/logic.htm
(1381 words)
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| | High School Mathematics Extensions/Logic - Wikibooks |
| | x AND y OR Notice this table involves three variables (x, y and z), so we would expect it to be bigger then the previous ones. | | | When an expression is hard to compute, we can first compute intermediate results and then the final result. | | | The connection between AND, OR and NOT is revealed by reversing the output of x + y by replacing it with x' + y'. |
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http://en.wikibooks.org/wiki/HSE_Logic
(2572 words)
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| | HW 2 solutions |
| | Ax Ey P(x,y) where P(x,y) is "x and y have chatted in an on-line chat-group" and the universal discours for x and y is the set of students in the class. | | | Ax P(x) where P(x) is "x has learned at least one programming language" and the universal discourse is the students in the class. | | | ((x elt of A) ^ (x not elt of {})) v ((x not elt of A) ^ (x elt of {}))} = {x |
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http://www.cse.ucsc.edu/~larrabee/ce16/hw2.html
(1414 words)
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| | [No title] |
| | */ static integer_t mod (integer_t x, integer_t y) { const int positive = (y > 0); /* We cannot use the library function `abs' to do these conversions since we don't know that integer_t is `int' which is the type of `abs'. | | | > n) /* Take N bits from X, with bit I as the least significant bit, and return them as the least significant N bits of a word whose other bits are 0. | | | The procedure returns (INIT * x ^ (8 * LEN) + A(x)) % PolyBasis.P. static poly_t poly_compute_mod (poly_t init, const byte_t* addr, integer_t len) { integer_t j; integer_t k; poly_t result = init; #ifndef FINGERPRINT_LITTLE_ENDIAN /* We don't need to do this if we already know the endianness. |
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http://www.edwardbear.org/dump/cherry/src/rabin64.c
(896 words)
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| | [No title] |
| | z) -} > md5_g :: XYZ -> Word32 > md5_g (x, y, z) = md5_f (z, x, y) > {- was: (x.&. | | | (y `xor` z)) > {- optimised version of: (x.&. | | | (complement z)) -} > md5_h :: XYZ -> Word32 > md5_h (x, y, z) = x `xor` y `xor` z > md5_i :: XYZ -> Word32 > md5_i (x, y, z) = y `xor` (x.. |
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http://web.comlab.ox.ac.uk/oucl/work/ian.lynagh/md5/haskell-md5-0.1.8/MD5.lhs
(739 words)
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| | [No title] |
| | If you want the result in both W and the register, you can use either: incf foo,w mowwf foo or: incf foo,f movf foo,w The stack is not accessible to the programmer in any way other than the call and return instructions. | | | Almost all data movement, arithmetic, and logic operations use W. Instructions that operate on W and a register (i.e., instructions ending in "WF", like ADDWF and MOVWF) allow the result to be placed in either W or the register (but not both). | | | For example: movlw 37 goto next next: movwf porta The goto instruction takes two cycles (1 to get the value of label "next" and 1 to load that value into the program counter) This is useful as a two-cycle NOP, and is often written as "goto.+1" to avoid the need for a label. |
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http://www.brouhaha.com/~eric/pic/faq.txt
(5939 words)
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| | Solutions to Test #1, CMPSCI 250 Spring 1999 |
| | (b) ``For any dogs x, y, and z, if x is smaller than y and y is smaller than z, then x is smaller than z.'' Solution: \forall x:\forall y:\forall z:[S(x,y)\wedge S(y,z) \rightarrow S(x,z)] | | | Question 5 (10): Rewrite this identity as a symbolic statement with boolean operations, quantifiers, and statements of membership in the individual sets A, B, and C. Solution: \forall x: [(x\in A)\wedge(x\in B\oplus x\in C)]\rightarrow (x\in A \vee x\in C) | | | (a) ``All poodles are smaller than Ebony.'' Solution: \forall x: P(x)\rightarrow S(x,e) |
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http://www-unix.oit.umass.edu/~cs250/exams/s99test1sol.htm
(958 words)
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| | [No title] |
| | It is essential that any operation that fails sets either x to NULL, err to nonzero, or why to anything but WHY_NOT, and that no operation that succeeds does this! | | | sq_ass_slice)(u, ilow, ihigh, x); } static int cmp_exception(err, v) object *err, *v; { if (is_tupleobject(v)) { int i, n; n = gettuplesize(v); for (i = 0; i | | | True : False; INCREF(v); return v; } static int import_from(locals, v, name) object *locals; object *v; object *name; { object *w, *x; w = getmoduledict(v); if (getstringvalue(name)[0] == '*') { int pos, err; object *name, *value; pos = 0; while (mappinggetnext(w, &pos, &name, &value)) { if (!is_stringobject(name) |
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http://www.cs.cmu.edu/afs/cs.cmu.edu/project/gwydion-1/python/python-1.0.2/Python/ceval.c
(597 words)
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| | [No title] |
| | y = x; z = rand(1,2); zi = find(z < p); y(zi) = not(x(zi)); % Feed y to the Viterbi algorithm for processing. | | | % x(1) = xor(xor(w(t), wD1), wD2); % Dumb Kozick way x(2) = xor(w(t), wD2); x(1) = xor(x(2), wD1); % Update wD1 and wD2 wD2 = wD1; wD1 = w(t); % Send x through the BSC, with output y. | | | z = rand; if (z <= 0.5) w(t) = 0; else w(t) = 1; end % Find convolutionally encoded bits, x. |
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http://www.eg.bucknell.edu/~kozick/elec47601/hardvit.m
(281 words)
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| | The Quinto Puzzle |
| | Mathematica, being the amazingly lightning-fast program that it is, is able to solve the 5x5 case in about a second: | | | An open question is, given a board size X by Y buttons, how many distinct solutions exist? | | | I find the above approach particularly appealing because it locates the solutions through a straightforward application of algebra. |
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http://splorg.org:8080/people/tobin/projects/quinto
(1247 words)
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| | [No title] |
| | These ;three bits are the 'root so far with ;01 appended', and is what we need to ;test against the upper 3 bits of N. bc sq7_2 ;oops, N must have been greater than ;0xc000. | | | The roots for each ; routine are compared. | | | ;For W, xor'ing a 0x60 clears the ;bit that was set when we loaded W with ;0x40 (note that the upper two bits of ;0x40 are 01). |
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http://www.dattalo.com/technical/software/pic/sqrt18.asm
(695 words)
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| | [No title] |
| | [after the name of an earlier window system called `W'] An over-sized, over-featured, over-engineered and incredibly over-complicated window system developed at MIT and widely used on Unix systems. | | | Commonly used in program comments to indicate areas that are kluged up or need to be. | | | [14967]control-Q. Node:xor, Next:[14968]xref, Previous:[14969]XON, Up:[14970]= X = xor /X'or/, /kzor/ conj. |
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http://www.datacrunch.net/jargon/topx.asp
(657 words)
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| | CS 210 - Computer Systems - Unit 4 |
| | x z b --------- 0 0 0 0 1 1 1 0 1 1 1 0 | | | x z C (the carry bit) --------- 0 0 0 0 1 0 1 0 0 1 1 1 | | | This operation can be implemented in a very simple digital circuit. |
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http://www.cs.bu.edu/faculty/djy/cs210/unit04.html
(3824 words)
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| | NSA's Dual Counter Mode Broken and Withdrawn |
| | Let the adversary ask a query DCM_Key(0, 0), obtaining a ciphertext that starts with first block C_1; now note that first block of DCM_Key(1, 2) will be C_1 xor 2. | | | Solve for x_0 (easy by our assumption that x_0 ends in 00). | | | C_2' = E_K((x_0 + 1 << 2) xor 2) xor (x_0 + 1) << 2 |
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http://ftp.die.net/mirror/cryptome/nsa-dcm.htm
(921 words)
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| | LWN: OpenBSD 3.4 Released |
| | These can be used for cards that are not supported by XFree86 4.3.0 or where XFree86 4.3.0 support is buggy. | | | Also, many popular ports have been pre-compiled for those who do not desire to build their own binaries (see BINARY PACKAGES, below). | | | Native i386 binaries have their executable segments rearranged to support isolating code from data, and the cpu CS limit is used to impose a best effort limit on code execution. |
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http://lwn.net/Articles/56283
(1932 words)
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| | W xor X - Wikipedia, the free encyclopedia |
| | W xor X, commonly written as W^X, is a security policy in some operating systems, such as OpenBSD, and the Linux kernel, in which a page can only be either writable (W) or executable (X), but never both at the same time. | | | This policy is enforced in order to alleviate the problem of buffer overflows and related attacks; by ensuring that the stack is not executable (since it is writable), arbitrary code injected into the stack will not execute but, instead, will cause the program to terminate with a signal. | | | According to Theo de Raadt, author of OpenBSD, W^X is pronounced "W xor X", or phonetically, "W zor X". |
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http://www.wikipedia.org/wiki/W_xor_X
(143 words)
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| | Rane Professional Audio Reference (X) |
| | XOR Acronym for exclusive OR, a type of logic gate where a logic 1 output is based upon A or B inputs being present - but not both. | | | X The electronic symbol for reactance -- the imaginary part of impedance. | | | Nomenclature designation for IEEE 802.3 or Ethernet cabling. |
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http://www.rane.com/par-x.html
(572 words)
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| | [No title] |
| | Notion of security: "simulation based" -- The adversary A learns nothing in the protocol because, even if it cheats, what it sees is just like a sample of a distribution that it could generate on its own. | | | Example: G3C example Example: HC example What does this "envelope" mean? | | | But we want to do this in a way that ONLY convinces V that x is in L. Eg, it should NOT make apparent a satisfying assignment (assuming SAT is not in BPP). |
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http://www.cs.ucdavis.edu/~rogaway/classes/227/fall03/lect10
(335 words)
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| | [No title] |
| | [end] Corollary 1 Let x and y be IEEE double-precision numbers satisfying 0 [less or = to] xy | | | b[sub]52[/sub] x 2[sup]e[/sup], b[sub]0[/sub] = 1, where e | | | Gustavson and W. Liniger, "A Fast Random Number Generator with Good Statistical Properties," Computing 6, 221-226 (1970). |
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http://www.research.ibm.com/journal/rd/461/agarwal.txt
(3623 words)
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| | [No title] |
| | Consider the following BNF grammar, G1: < XOR > ::= < XOR > + < XOR > | | | Finally, there will NOT be any SCHEME questions on the exam. |
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http://www.albany.edu/~csi311/sample.exam2.questions.html
(381 words)
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| | MoonJihad's Page of LiveJournal Nothingness |
| | Yesterday, I was reading about the techniques implemented in OpenBSD to make exploiting software bugs harder, such as W^X (W xor X) and using stack canaries. | | | You can read the presentation Exploit Mitigation Techniques on OpenBSD's website, it's quite an interesting read. |
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http://www.livejournal.com/users/moonjihad
(1796 words)
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| | Search Encyclopedia.com |
| | For example, consider the problem of determining the area under a given curve y=f(x) between two values of x, say a and b. | | | Look up W xor X on HighBeam™ Research. | | | Shakespeare, William -> The Poetry Shakespeare's first published works were two narrative poems, Venus and Adonis (1593) and The Rape of Lucrece (1594). |
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http://www.encyclopedia.com/searchpool.asp?target=W+xor+X
(141 words)
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| | OpenBSD |
| | This will make OpenBSD the only open source BSD operating system to ship with its own X implementation. | | | Privilege separation, privilege revocation, and randomized loading of libraries also play an ever increasing role in the security of the system. | | | W^X (pronounced: "W xor X") is a fine-grained memory management scheme ensuring that memory is either writable, or executable, but never both, providing yet another layer of protection against buffer overflows. |
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http://www.sciencedaily.com/encyclopedia/openbsd
(643 words)
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| | SX Microcontroller Bit Math Method - swap w and f without a temp register |
| | Recently I had a project where a subroutine took a value in W and saved to a software stack: | | | Trouble is it uses a temporary variable which I didn't have (it is in an interrupt). | | | I think this may be an old technique - I have vague memories of something similar from the pre-history of programming, but only found a use for |
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http://www.ecomorder.com/techref/ubicom/lib/math/bit/swap_sx.htm
(310 words)
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| | [No title] |
| | A }/q{bitshift}/a{rand}/:{/v H/X H/W X 2 z A/S 0 v 2 z B A/Q S array A ` S R{p 15 x}r 1 1 W 2 y{= 2 x S ! | | | z p 8 x}r W W S ! | | | !{= 1 x R W z p 4 x}r Q Q ? |
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http://www.umich.edu/~archive/mac/misc/documentation/printermaze.txt
(471 words)
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| | Health : Article 'Color blindness' |
| | This is either Autosomal Dominant or X linked Dominant. | | | Finally, as yet more red is added, the remaining, protanomalous, observers will declare a match at a point were everyone else is seeing the mixed light as definitely reddish. | | | There is a third, blue color opsin gene in humans that is present on one of the numbered chromosomes (autosomes), specifically chromosome 7. |
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http://www.poneweb.com/DisplayArticleFull37433.html
(2235 words)
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| | [No title] |
| | Here is a part of a typical (incorrect) solution for 6(a): Let R(x,y) = "x | | | Then R(x,y) -> R(y,x) and since x and y are arbitrary male humans, by universal generalization, we must have that \forall x \forall y [R(x,y) -> R(y,x)]. | | | Certainly, if x is a brother of y, since x and y are both male, y is a brother of x. |
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http://www.cs.toronto.edu/~ruppert/238H-98/a1comments.txt
(1230 words)
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| | [No title] |
| | W^X - The Mechanism Many bugs are exploitable because the address space contains memory that is both writeable and executable (permissions = W | | | Using model-specific TLB handling (often undocumented) it may be possible to do this. | | | X) A serious hinderance would be to ensure no pages have W |
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http://www.openbsd.org/papers/pacsec03/e/mgp00005.txt
(50 words)
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| | Intel® IOP331 I/O Processor |
| | The AAU speeds the transfer of read and write data to the memory controller and computes data parity across local memory blocks. | | | The PBI provides two chip selects and supports programmable bus width and wait states for two memory windows. | | | The Application Accelerator Unit (AAU) contains a hardware-based XOR capability using a 1 Kbyte queue to accelerate RAID-related parity calculations. |
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http://www.intel.com/design/iio/iop331.htm
(1265 words)
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| | Homework #3 |
| | Y0 = A3 (A2' + A1' A0') + A2' (A1 xor A0) + A3' A2 A1 A0 PLA Programming table: | | | Prove that the dual of XOR is also its complement | | | F = F1 (AB' + A'B) F = F1 (A xor B) |
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http://william.krieger.faculty.noctrl.edu/archive/c2004_01_csc480/homework/hw03/hw03_solution.htm
(174 words)
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| | NREVERSAL of Fortune |
| | Chen, W. "A formal approach to program inversion". | | | rot(x,c) rotates the bit pattern in x by c bits; inverse is rot(x,-c)=rot(x,w-c). | | | Chen, W., and Udding, J.T. "Program Inversion: More than Fun!". |
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http://www.pipeline.com/~hbaker1/ReverseGC.html
(8264 words)
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| | OSNews.com |
| | Owning a well-trusted server would put you in an excellent position to take over client machines running windows. | | | On x86-32, there's a 1gb virtual gap between W and X pages. | | | Putting up a malicious Java applet or Active X control on something like www.yahoo.com would probably cause some serious damage. |
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http://www.osnews.com/comment.php?news_id=4684&limit=no
(951 words)
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| | [No title] |
| | $AUUGid: www/data/events/2004/auug2004/theo/mgp00008.txt,v 1.1 2004/09/04 08:42:51 davidp Exp $ W^X - The Mechanism Many bugs are exploitable because the address space has memory that is both writeable and executable (permissions = W | | | X) Note this location has to be executable We could make the stack non-executable... | | | How about a generic policy for the whole address space: A page may be either writeable or executable, but not both (unless application requested...) We will call this policy W ^ X (W xor X) |
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http://www.auug.org.au/events/2004/auug2004/theo/mgp00008.txt
(81 words)
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| | Software Development Online: June 2003 |
| | Most buffer overflows rely on being able to write to a piece of memory and then jump to it." Finally, other security enhancements include heavy use of chroot, privilege separation for the X window server and xconsole, default RSA blinding in | | | To speed performance, it omits instrumentation code from some functions. | | | For those architectures that can support it, OpenBSD offers a "fine-grained memory permissions layout" called W^X (and pronounced "W xor X"). |
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http://ftp.rootr.net/pub/web/misc/openbsd-article
(1467 words)
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| | [No title] |
| | >= typedef struct st_stroke_point STROKE_POINT; struct st_stroke_point { int x, y; STROKE_POINT *next; }; static STROKE_POINT *stroke_points = NULL; @ %def stroke_points @section Function @code{x_stroke_add_point()} @defun x_stroke_add_point w_current x y @end defun | | | >= /* traverse list as well as free each point as you go along */ void x_stroke_erase_all(TOPLEVEL *w_current) { STROKE_POINT *temp; while(stroke_points != NULL) { #if DEBUG printf("%d %d\n", stroke_points->x, stroke_points->y); #endif /* was xor, wasn't working out... |
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http://cvs.seul.org/viewcvs/viewcvs.cgi/*checkout*/eda/geda/devel/gschem/noweb/x_stroke.nw
(306 words)
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| | Boolean and Shifting Operations |
| | x or 1 = 1 or 1 0 0 1 0 1 1 0 | | | Note on Assembly Language Bitwise Instructions: The and, or, and xor instructions have the same operand rules as add. | | | For example, to flip bit 7 of eax (or n in the case of C Language), use |
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http://www.cs.sjsu.edu/~fecteau/cs140/Bool&Shift.html
(1173 words)
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| | [No title] |
| | xor w (x, y as P.INT (n, _)) = if iszero n then x else if iscomzero x then x else baseXor w (x, y) | | | or w (x, y as P.INT (n, _)) = if iszero n then x else if iscomzero x then x else baseOr w (x, y) | | | apply (("or", [w]), [x, y]) = or w (x, y) |
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http://www.eecs.harvard.edu/~nr/toolkit/working/sml/rtl/patrew.nw
(563 words)
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| | Modula-3: Required interfaces |
| | y *) PROCEDURE GE(x,y: T): BOOLEAN; (* x >= y *) | | | PROCEDURE And(x,y: T): T; (* Bitwise AND of x and y *) PROCEDURE Or (x,y: T): T; (* Bitwise OR of x and y *) PROCEDURE Xor(x,y: T): T; (* Bitwise XOR of x and y *) PROCEDURE Not (x: T): T; (* Bitwise complement of x *) | | | And here are the logical operations on bit sequences: |
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http://www.cs.wichita.edu/~rodney/cs810/fl2004/reqd-interfaces.html
(1038 words)
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| | ANSDIT - The letters "X", "Y", and "Z" |
| | The scaling value should be the same in all directions. | | | ANSDIT - The letters "X", "Y", and "Z" Return to ANSDIT | | | In networking, a directory containing the electronic addresses of businesses organized by product or service. |
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http://www.ncits.org/tc_home/k5htm/z.htm
(193 words)
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| | [No title] |
| | for 1 = 16 to 79 do W_i + (X_i-3 xor W_i-8 xor W_i-14 xor W_i-16)<<<1 2. | | | {0,1}^n universal hash function E: \K2 x {0,1}^n -> {0,1}^n prf Define: F_{K1,K2}(M) = E_{K2}(H_{K1}(M)) Claim that this is a good PRF. | | | General lemma that pi, pi(K xor.) looks like pi_1, pi_2 -- if ask q queries, can't distinguish better than q^2/2^n. |
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http://www.cs.ucdavis.edu/~rogaway/classes/227/fall01/lect8
(817 words)
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| | Crypto Archives: RE: Lucre fixed? |
| | > x is the seed, which should be the size of the modulus - 321 bits. | | | > for Lucre, as it allows the x seed value to be embedded in the padded |
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http://archives.neohapsis.com/archives/crypto/1999-q4/0657.html
(237 words)
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