Programming :: Implementation Of RSA Algorithm In C / C++
Aug 2, 2010Can I know the implemention of RSA(Encryption and decryption) algorithm in C / C++.
View 1 RepliesCan I know the implemention of RSA(Encryption and decryption) algorithm in C / C++.
View 1 RepliesI have a copy of the MD5 algorithm and I'm taking a look at the source. It's pretty interesting but there are a few things that I'm curious about and I was wondering if anyone a bit more intuitive than I could help me out.The function declarations in the MD5 files are a bit unfamiliar to me. There is a macro used called PROTO_LIST, which I'm still not sure as to what this thing is doing exactly, but it's littered everywhere throughout the source.The signature here isn't too unfamiliar to me with the exception of the position of the PROTO_LIST macro. So here is a function with an unnamed argument of type MD5_CTX*.To me, this resembles an initializer list found in C++ with constructors but I certainly don't think that is the case here. So my questions about this are (1) how is this legal code in C and (2) what functionality has the PROTO_LIST macro provided for the function?
View 3 Replies View RelatedI've implemented a program URL... which reads digital IF data from a radio receiver through a named pipe, measures power levels, and sends the result to stdout. The program is interactive; there is a thread that reads from stdin to watch for commands, a thread that constantly either reads data from the named pipe or throws data away, and an array of processing threads. The program uses GTK+extra to plot the signals. The IF data stream bandwidth exists at the limits of today's technology (is very very fast).
Problem Statement:The program works fine with a few bugs. I've learned since I've made it that using global state variables to coordinate threads isn't a good way of doing it. I also only had knowledge of mutexes and polled the state variable instead of using other methods.My reimplementation will use the following:
- One "Stdin Command Monitoring" thread
- One "Get data from named pipe" thread
- One post-processor thread
- N Processing threads
All threads are alive during the life of main()There are N buffers. Data will come in from the named pipe, and the "Get data" thread will write the data to an "available" buffer. When the buffer is full it will be marked as "full". There will be N processing threads, one for each buffer. When a processing threads' buffer is full, it will process the buffer and save the result to a final buffer. At the end of a number of averages, the post-processor thread will perform a final process on the final buffer and send the results to stdout.
I am new to this forum and to Networking as well. I have chosen to implement:
1) SIP Client using C' language
2) Platform: Windows
3)Its going to be on command line
my problem is that I need some reference like books, material or website where I can learn how to write the code from scratch or port the code according to my requirements. My implementation should serve the purpose like two SIP clients should communicate with each other for exchange of Audio data.
From this thread I've decided to try add a feature of removing local port forwardings in ssh.Here are some very ugly and not-yet working hacks what I made so far:
* Patch for channels.c
* Patch for channels.h
* Patch for clientloop.c
I was clearly expecting this to work without any troubles-everything seem to be logically correct, but I made a programming mistake somewhere: don't know where, maybe you will point me to this?Many sites say there is a WAY AROUND with -D param(starting socks proxy as a tunnel-generator), added since 5.2, but I don't need that way around. I need a way through. I use exact ports for exact services and if I want to change it runtime I'd like to have ability to do so.If you have other ideas or points instead of coding this, please share them here & here(original question).
I have a timer thread, and when it expires, it sets a flag. The only problem is, if any higher priority thread comes in between, then the timer is not expired in real time.Thus i want to set a highest priority to my thread. Now, i know 2 algos, which can make my thread in real time are: SCHED_FIFO and SCHED_RR.
So, here are my queries: 1) Which scheduling algo is best suited for this purpose? 2) Is it guaranted to work in real time if i use that algo (you suggest in 1) and set the max_priority by getting the maximum settable priority for that particular algorithm using, int sched_get_priority_max(int policy);
I've got a bit of an obscure question for you to test your brains a wee bit. I'm trying to implement a search program to find areas of high density in a binary string.
E.g.
Code:
[0001001010
0001110001
0000001000
1001000010
0101100100]
Where density is the number of 1's / number of digits with a maximum number of digits being the current number in a buffer (in this example 50). So for the example the density for the whole buffer is 15/50. But the density of Buffer[14..20]=[1110001]=4/7. So if looking for areas of density = 1/3 it would find the longest sequences of density over 1/3.So in the example. Buffer[4..9]=[100101]=3/6=1/2 which is above 1/3 but it is within the Buffer[4..48]=[100101000011100010000001000100100001001011001]=15/45=1/3
I have an algorithm guys called "Self Configurable Diagnosis Algorithm" but i don't have program for this.help me regarding that program and which type of Tcl script will be better suitable for that.
View 3 Replies View RelatedI have two functions:
Quote:
void func1(std::string &s)
{
s.clear();
}
[code]....
Is there a way to create one template function for both vector and string that would clear them?
I need to simulate dijsktra's algorithm using network animator of ns2. how to write a tcl script for my code. This tcl script runs the dijsktra code and simulates its running on network animator.
View 1 Replies View RelatedAStar works on the basis of straight lines, AFAIK. In my case, we have geocoordinates and I can get the straight line distance between the waypoints. But I am wondering how approximate will the route calculated on this basis be? The actual distance "by road", which actually matters can be different.
Example. Assuming A and B are on the same plane, and will be equidistant from the goal point, if we consider a straight line between A and the goal point and, B and the goal point. The distance "by road" between A and the goal point may be greater or lesser than B. But because the AStar works on the basis of straight lines, it will return both the routes as the shortest. If yes, then which algo should be considered , if we want the results on the basis of actual distance in Km/m?
i need a program for Encryption and Decryption using RSA algorithm in JAVA ..
View 9 Replies View Relatedi try to understand this algorithm but i cann't. [URL] I encounter problem understand the algorithm of fixed base windowing exponentiation algorithm ? What is fixed base in the first place ? How this algorithm works ?
View 5 Replies View Relatedalgorithm:breada
input: file system block number for immediate read
file system block number for asynchronous read
output:buffer containing data for immediate read {
if(first block not in cache) {
get buffer for first block
if(buffer data not valid)
initiate disk read }
if(second block not in cache) {
get buffer for second block)
if(buffer data valid) //line 1
release buffer else
initiate disk read //line 2 }
if(first block was originally in cache) //line 3 {
read first block
return buffer }
sleep (event first buffer contains valid data)
return buffer }
Here is an algorithm for block read algorithm. I have problem in
line 1: If buffer data is valid why is it releasing the buffer?
line 2: If buffer data valid why is it initiating disk read. It should have read directly from buffer?
line 3: It should be the first condition as if it is there in cache then it should return it without delay?
Does anyone know of a C Language Data Structure Tutorial? I have not been able to find anything much to speak of myself.
View 4 Replies View RelatedThe algorithm for reading and writing disk blocks use the algorithm getblk to allocate buffers from the pool. In the algorithm getblk, if the kernel removes a buffer from the free list, it must raise the processor priority level to block out interrupts before checking the free list. Why ?Where can i find the C implementation of the above algorithm for buffer allocation in the linux source code ?
View 1 Replies View RelatedI want to simulate a serial protocol in user space program to test reception algorithm. The protocol is similar to UART protocol but frame format is different. The duration of 1 bit is 114,46 us. In my main function I'm creating two threads. Tx for simulating transmitting data and Rx for reception data. For measure time I use create_timer() function and signals. Each thread has its own timer and signal handler. Tx timer uses SIGUSR1 and Rx timer uses SIGUSR2. Tx thread sets the global variable and Rx reads it.
The timers are set to sample with 114,46 us period. When they reach this value signal handler should set the flag. Flag is check in thread and some operation are made. When I set the timers period for longer time (100 ms) everything works fine but when I change it to default value (114,46 us) the Rx thread doesn't receive the proper data. I am wondering if the 114,46 timer period is possible to simulate in user space? Whether the time will give me the proper resolution ? Theoretically it should provide 1 ns resolution.
not able to solve an error when i try to do a wireless scenario in ns2.
num_nodes is set 3
warning: Please use -channel as shown in tcl/ex/wireless-mitf.tcl
INITIALIZE THE LIST xListHead
i have done everything that all the documentations have said and i still cant get this bloody thing working. some one give me the exact commands that removes all traces of all wine packages. and then can someone give me the exact commands to install.
which user i must be doing this under and exactly what i must configure in the config files. all that i want too accomplish by this is to successfully play games on my pc.
IPtables, implementing each type of NAT
-Full Cone NAT
-Restricted Cone NAT
-Port Restricted Cone NAT
-Symmetric NAT
using IPTables.
Explanation:
Full Cone: A full cone NAT is one where all requests from the same internal IP address and port are mapped to the same external IP address and port. Furthermore, any external host can send a packet to the internal host, by sending a packet to the mapped external address.
Restricted Cone: A restricted cone NAT is one where all requests from the same internal IP address and port are mapped to the same external IP address and port. Unlike a full cone NAT, an external host (with IP address X) can send a packet to the internal host only if the internal host had previously sent a packet to IP address X.
Port Restricted Cone: A port restricted cone NAT is like a restricted cone NAT, but the restriction includes port numbers. Specifically, an external host can send a packet, with source IP address X and source port P, to the internal host only if the internal host had previously sent a packet to IP address X and port P.
Symmetric: A symmetric NAT is one where all requests from the same internal IP address and port, to a specific destination IP address and port, are mapped to the same external IP address and port. If the same host sends a packet with the same source address and port, but to a different destination, a different mapping is used. Furthermore, only the external host that receives a packet can send a UDP packet back to the internal host.
On the netfilter mailinglist, Pedro Goncalves suggested the following:
192.168.2.170 is "public" address and 10.0.0.1 is "private" address
/-"Full Cone NAT", with the following rules:/
HTML Code:
iptables -t nat -A POSTROUTING -o eth0 -j SNAT --to-source 192.168.2.170
iptables -t nat -A PREROUTING -i eth0 -j DNAT --to-destination 10.0.0.1
/-"Port Restricted Cone NAT", with just a single rule:/
HTML Code:
iptables -t nat -A POSTROUTING -o eth0 -j SNAT --to-source 192.168.2.170
How to implement Network Protocols.
View 1 Replies View RelatedHave any of the below TCP based applications are implemented over SCTP in Linux ?
1. ftp
2. telnet
3. HTTP
Or any other applications ?
I am trying to understand the implementation of iptables and netfilters. Any good links or docs.
View 1 Replies View RelatedI'm in need of some advise from you guys. I'm currently running a live production serverA, and last week it went down for a couple of hours which was really bad to say the least.
I've been thinking about building a mirror serverB that will rsync my data nightly. Now I don't want to load balance here, I just need to be able to switch to serverB when serverA goes down for any reason.
Would the best solution for this is to change my main nameserver entry when I want to switch ? I'm just curious if it will be a few hours or an instant change.
I thought I'd ask before attempting this live.
I need to optimize the implementation of DSR algo using NS-2. Now i need to identify the first of all "the parameters which i can change and which are effective in optimization point of view." I want to get into the c++ code as well as header files which are used to implement DSR algo.
View 4 Replies View RelatedI am trying to find a leach protocol implementation for ns2.34 but all links available are dealing with ns2.27 Are the instructions valid for ns2.34?
View 4 Replies View RelatedI'm looking for linear hashing implementation in C language. PS: I have to implement this on Ubuntu 10.04 Linux on 64 bit machine.
View 2 Replies View RelatedI'm Redhat 5 user, and I want to implement Kernel-based Virtual Machine. I tried too much search in google but I cant find the perfect instruction regarding it.
View 3 Replies View RelatedSubject of my school work:"Web interface for managing firewall and band on the access server (Linux)"I have a big problem because I do not know how to safely implement the change in the system and show the logs on the Web page.Unfortunately, the number of solutions for today is enormous and it is increasingly difficult to me to decide on the right.They are:
1. Launching a web server with root privileges (the default mode of miniserv'a Webmin)
2. CGI scripts on apache SUID (mode webmin on "foreign" server)
3. suPHP or suexec
4. Cron implements changes to the root
5. Daemon in C "periodically" implement changes in the configuration files created by PHP
6. Daemon in C to implement the changes requested in the configuration files created by PHP
7.Use SSH in PHP and after logging into the root of execution of commands in the configuration files created by PHP (the root password in the DB)
8.Use SSH in PHP and after logging into the root of execution of commands in the configuration files created by PHP (the root password, enter manually)
9. Like the above so that the use of sudo and user rights only to the necessary shell commands
10. Add the user apache in the /etc/sudoers can perform all the necessary applications shell commands
11. Seize the opportunity to command: shell_exec ( `sudo php-f / home /example/script.php`), and /etc/sudoers
My network diagram is internet<---->dansguardian proxy(centos5)<--->my network i have blocked facebook for my network but now i want to give only 2 ips to get its access & i do not want to enter these ip in exceptioniplist as if i doo so then they will be able to access all the sites that i have blocked. and if i am giving this entry [URL] in bannedsite list it is also not working.....
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