TopicAnalysis program, before running to think: whether this program can return correctly?After running, think again: why is this result?Through this program to deepen the understanding of the relevant content.Paste in the code as follows:assueme cs:codesgcodesg segment mov ax,4c00h int 21hstart: mov ax,0 s: nop nop mov di,offset s mov si,offset s2 mov ax,cs:[si] mov cs:[di],ax s0: jmp short s
Assume Cs:codeCode segmentMOV ax,4c00hint 21hStart:mov ax,0S:nopNopMOV Di,offset sMOV si,offset s2MOV Ax,cs:[si]mov cs:[di],ax//the two bytes at S2 to s where the jmp short S1 to SS0:JMP Short SS1:mov ax,0int 21hMOV ax,0S2:JMP short S1NopCode endsEnd StartThe strange thing is that when executing a program in the execution of a DOS display in
Rebecca Casey is flying from San Francisco, home to Boston. She is very worried and upset. She has just learned that her father is in a hospital.What is it?It's your father. He's in the hospital.I have to call home. My father's in the hospur. May I use your phone?Of course. There's a phone in the kitchen. It'll be quieter there.When she telephoned the hospation, she knew she had to return at once. The situation was serious.Oh, my God! Is he OK? Well,
The 8086CPU transfer instruction is divided into the following categories:1. Unconditional transfer instructions (e.g., JMP)2. Conditional Transfer Directives3. Cyclic instructions (e.g. loop)4. Process5. InterruptsOne, operator offsetHandled by the compiler, is a pseudo-instruction, the function is to get the offset address of the labelIn question 9.1, the data to be copied: the length of the mov ax,bx instruction (machine code) is two bytes, or 1 ch
Part 1: Ajax Introduction
Ajax is composed of HTML, JavaScript, DHTML, and Dom. This outstanding method can convert clumsy web interfaces into interactive Ajax applications.Program. The author of this article is an Ajax expert who demonstrates how these technologies work collaboratively-from an overview to a detailed discussion-to make efficient web development a reality.Link: http://ibm.csdn.net/ISN_J.aspx? Action = JMP pointid = 2301
Part 1: us
Four collected documents
1. Ajax security:Http://bbs.hackbase.com/search.php? Searchid = 607 orderby = lastpost ascdesc = DESC searchsubmit = Yes2. Ajax materials from the Chinese IT lab:Http://web.chinaitlab.com/List_1905.html3. Ajax video tutorialHttp://bbs.langsin.com/forumdisplay.php? FID = 214. Foreign Ajax Learning WebsitesHttp://www.asp.net/ajax/5. Get started with Ajax!Http://www.ibm.com/developerworks/cn/web/wa-aj-backend? S_tact = 105agx52 s_cmp = tec-csdn
Ajax from entry to entry
?I know... it's late. I have to be up early for work tomorrow.All right, I'll take you home.So, about our date on Thursday ...? I'll pick you up at seven, OK?Sounds good.This is really crazy, Rebecca Casey.Good night, Matt.
Oh, good. It's here.Welcome to the Boston School of Music, where your musical career begins.The Boston School of Music has given me everything that I wanted in a school.The
namespace.
III. The extend method of jquery also has an overload prototype:
Extend (Boolean, DEST, src1, src2, src3 ...)
The first parameter 'boolean' indicates whether to perform a deep copy. The other parameters are the same as described above. What is "Deep copy"? Let's look at an example:
VaR result
=
$. Extend (
True
,{},{Name:
"
John
"
, Location: {city:
"
Boston
"
, County:
"
USA
"
}},{Last:
"
Resig
,loc) VALUES (+, ' SALES ', ' CHICAGO '); INSERT INTO dept (deptno,dname,loc VALUES (' OPERATIONS ', ' BOSTON '), insert INTO dept (DEPTNO,DNAME,LOC) VALUES ("OPERATIONS", ' BOSTON '); INSERT into Dept (Deptno,dname,loc) VALUES (+, ' OPERATIONS ', ' BOSTON '); COMMIT;The data displayed at this point is:Sql> select * from dept; DEPTNO dname LOC--------
Linux Practice--Program hackOne, Master NOP, JNE, JE, JMP, CMP assembly instructions machine code
The NOP:NOP instruction is the "null instruction". When executing to the NOP instruction, the CPU does nothing, just as an instruction to execute the past and continue executing a command behind NOP. (Machine code: 90)
JNE: Conditional transfer directives, if not equal, jumps. (Machine code: 75)
JE: Conditional transfer instruction, if eq
, oracle considers that the condition rownum> n (Natural Number of n> 1) is still not true, so records cannot be found.
Less than or equal:
BYS @ bys3> select * from dept where rownum DEPTNO DNAME LOC
-------------------------------------
10 ACCOUNTING NEW YORK
BYS @ bys3> select * from dept where rownum DEPTNO DNAME LOC
-------------------------------------
10 ACCOUNTING NEW YORK
20 RESEARCH DALLAS
Greater than or equal:
BYS @ bys3> select * from dept where rownum> = 1;
DEPTNO DN
the Log_archive_dest_n parameter in primary, set physical standby forward redo to cascaded destination.Define transfer mode: LGWR async or LGWR SYNCSet the Valid_for property to enable redo forwarding3. Forwarding Redo physical standby turn on archive mode4. Configure the physical standby log_archive_dest_n parameter of the forwarding redoParameter configuration case:Boston Database (Primary Role):Db_unique_name=bostonstandby_archive_dest=/arch1/boston
Usage 1:jmp short label (go to label to execute instruction)The JMP directive in this format implements a short transfer within a segment that modifies the IP to a range of -128~127, that is, it can move forward up to 128 bytes, and a backward transfer can be up to 127 bytes.Transfer, only modify IP, such as JMP axTransfer between segments, while modifying CS and
plays a similar role, it can direct location-independent function calls to absolute addresses. The link editor cannot resolve the transfer of a program from an executable file or shared library target to another execution. As a result, the connection editor can only arrange some entries containing the transfer control to the program connection table (PLT. In system V, the program connection tables are located in the shared body, but they use the addresses in the private global offset table. Dyn
is filled, the cmp [Addr] And 0xff will be used to determine whether to check the encryption option for processing. There is Magic JUMP, but the Shell API address has been redirected, and the Patch code needs to be restored.>The code is not optimized, and there is no time to optimize it. There are too many records to analyze the main program.The Patch code is as follows:Code:00B60000 60 pushad00B60001 9C pushfd00B60002 BE 00104000 mov esi, 0x401000 Code segment Addr00B60007 BF 00404000 mov edi,
, while the functionsInitbreakThe value is 004120f0, and their values are different. Why?
Just move forward and there will be an answer,
0: 000> U 41118b-8Testc! ILT + 380 (_ rtc_initialize) + 0x2:00411183 25.0e985 and eax, 85e90000h00411188 0e push CS00411189 0000 add byte PTR [eax], AlTestc! ILT + 390 (_ initbreak ):0041118b e9600f0000 JMP testc! Initbreak (004120f0)Testc! ILT + 395 (_ controlfp_s ):00411190 e987300000
to 'if (a = B) in the code ). The Cmp command indicates the subtraction operation. Therefore, it means to compare two variables. If they are not equal, jump to the memory address and print the string "a B are not equal". Otherwise, if the variables are equal, the jnz command will be skipped and the string "a B are equal" will be printed ". If multiple if statements are embedded, you will see multiple cmp, jnz, and jz, and then print strings or other operations in the future.Loop
The cyclic st
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