prompt in the ocean of strings: "You have purchased and registered the shared data protection expert advanced Edition Software, thank you for your support! ". This prompt is no longer clear. Double-click it and you will be directed to the corresponding code. We still perform analysis in the order of first flow and then algorithm, just like the previous analysis process.
An amazing burst"First, find the place where the registration process starts, follow the registration success prompt to look u
overflow, so instead of There are also problems with the number of signed and unsigned numbers, and when the length is particularly large, the correct result is not obtained.So instead:unsigned Ifor (i = 0; i ****************************************************************Declaration: The following various byte-length representations are based on the IA32 instruction set architecture.Machine-level representation of the program:A IA32 central processing unit contains 8 registers that store the
This article is divided into 3 modules.
Example---example of this directive
explain ---to the point where the instructions are difficult to understand
Practice ---in order to become more familiar with the directive
1.1 Signed Division instruction and take-over example:In the C language to complete the 8/2 assembly instructions are as follows:in C language to complete 8 2 of the assembly instructions are as follows:An example of a 4-byte division and take-rest operation is
Previously asked on edx code (edx Google Group) How to expand a field for course, such as adding a category field to a course.The reply says to add the field you want directly to the couesefields. Position common/lib/xmodule/course_module.py after. The field is automatically displayed in the Advanced settings. In this way I find that the field is indeed a property of course (experiment in the shell). Howeve
basically no design pattern, which cannot reflect the great superiority of the C ++ language in object-oriented design. Let's take a look at how this virtual works?
[CPP] View plaincopy
76: employee P;
0040128d Lea ECx, [ebp-10h]
00401290 call @ ILT + 45 (employee: Employee) (00401032)
00401295 mov dword ptr [ebp-4], 0
77: manager m;
0040129c Lea ECx, [ebp-14h]
0040129f call @ ILT + 65 (Manager: Manager) (00401046)
004012a4 mov byte PTR [ebp-4], 1
78: employee * E =
of system_call. In system. h:
//// Set the system call function. // Parameter: n-interrupt number; addr-interrupt program offset address. // Idt [n] corresponds to the offset value of the interrupt number in the Interrupt Descriptor Table. The Interrupt Descriptor type is 15 and the privileged level is 3. # Define set_system_gate (n, addr) _ set_gate ( idt [n], 15,3, addr) /// set the macro function of the gate descriptor. // Parameter: gate_addr-Descriptor address; type-Descriptor field value
converted to the address of the method to be called and the list of its parameters (stored inTvarrec array), how to pass parameters when calling it. Some preparations are required:
1. First, let's take a look at the passed parameter table: Params. Its type is called Variable-enable by Delphi.Put an array (variant open array), equivalent to array of tvarrec, that is, Params isArray of tvarrec members. In other words, all types of parameters areDelphi is automatically converted to tvarrec (see
state transition.
on each platform, there is a specific directive that converts the execution of a process from user state to a core state, which is called the Operating system trap (operating system traps). After the process has been executed into the command, it can run the system call code in the kernel mentality.
In Linux it is through soft interrupts to achieve this, on the x86 platform, this instruction is int 0x80. That is, in Linux, the interface of the system call is a special case o
EAX, the parameter is EBX, ECX, edx, EDI, ESI to pass. Writing Shellcode To write Shellcode under Linux, you can use GCC to assemble directly. s file to compile the link, generate the standard executable Elf file, but also can be directly tested, but it is not convenient to extract machine code is very inconvenient.In order to facilitate the extraction of machine code, using the NASM compiler to generate the bin file, no other format data, convenient
After the PPPOE between the user and the Access Server is established, a PPP session can be established on it. PPP sessions are established in three phases: LCP negotiation, authentication, and IPCP negotiation.
The LCP negotiation phase is the same for PPP termination and PPP resumption. Authentication and IPCP negotiation
Interesting ipsec vpn connection ConfigurationI. Level 1: PIX-PIXThe customer proposed to look at a vpn model. In view of the demonstration nature, the requirements were not high, nor did the customer propose the requirements for negotiation parameters and network structures, we chose cisco pix, a popular vpn device, for point-to-point communication.For hardware vpn products, the configuration methods are similar because it does not involve installati
1. Handshake and key negotiation processClient Authentication server based on RSA handshake and key exchange for an example TLS/SSL handshake processLook at a hand-drawn timing diagram. (1). Client_hello Client initiates a request to transmit the request information in clear text, including the version information, the Cipher Suite candidate list, the compression algorithm candidate list, the random number, the extended field information, The rel
results are as follows: One of the first two cases overflowed, and only the third was normal. And then we'll look at their assembly code, which is the assembler code I disassembled with Objdump: 1 intMainintArgc,char *argv[])2 {3 8048394: - Push%EBP4 8048395: theE5mov%ESP,%EBP5 8048397: theE4 F8 and$0xfffffff8,%esp6804839a: theEc - Sub$0x30,%esp7Long Muln =203879;8804839d: C7 - - 0c the1cGenevamovl $0x31c67,0xc (%ESP)980483A4:xx TenLong Long MULNL =2
Author: uuk[Software name]: Total Commander[Software Version]: 7.56a[Shelling method]: new version without shelling[Programming language]: Borland Delphi 2.0 [Overlay][Tools]: OD PEID IDA[Operating platform]: Windows XP[Software introduction]: A pretty good dual-column File Management Software[Author's statement]: it is only for research purposes. Please purchase a genuine version for use.We know that Total Commander has self-verification. by tracking the CreateFile and ReadFile functions, it is
8. Offset is the number of immediately. For example, [EBP + EDX * 8 + 200] is a valid address expression. Of course, in most cases, it is not necessary to have such a complex relationship as inter-address, proportional factor, or offset.
The basic unit of memory is byte ). Each byte has eight binary bits. Therefore, the maximum number of characters that each word can save is 11111111, that is, 255 in decimal format. In general, it is more convenient
# reset the IDT and gdt tables at the new location.16 call setup_idt # Set IDT. First, fill in the descriptor of the default processing process for all the 256 interrupt doors.17 Call setup_gdt # Set gdt.18 movl $0x10, % eax # Reload all segment registers after gdt is changed.19mov % ax, % DS20mov % ax, % es21mov % ax, % FS22mov % ax, % GS23lss init_stack, % ESP24 # Set the 8253 timing chip. Set counter channel 0 to send an interrupt request signal to the interrupt controller every 10 ms.25 mov
The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion;
products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the
content of the page makes you feel confusing, please write us an email, we will handle the problem
within 5 days after receiving your email.
If you find any instances of plagiarism from the community, please send an email to:
info-contact@alibabacloud.com
and provide relevant evidence. A staff member will contact you within 5 working days.