Tuesday, September 12, 2023

Qualcomm Snapdragon

&A

How can I get started with development today?

You can find more information on the development kit here: https://www.qualcomm.com/developer/windows-on-snapdragon#overview You can find documentation, tools, support, links to purchase dev kits and much more on this page to help you get started

What kind of support does Qualcomm provide with development?

You can find documentation to help you get started here: https://docs.qualcomm.com/bundle/publicresource/topics/80-62010-1/Overview.html?product=Windows%20on%20Snapdragon You can also find some FAQ's, course on Qualcomm Academy and join the discord channel. https://www.qualcomm.com/developer/windows-on-snapdragon#support Qualcomm engineers and SME's are standing by to answer any question that you man have.

Wednesday, September 6, 2023

detect file change in bash redhat

#!/bin/sh

old=$(tail -l $1)

while true
do
sleep $2
new=$(tail -l $1)
if [ "$old" != "$new" ]
then
     echo "file changed"
     old=$new
else
     echo "file not changed"
fi
done

--------------------------- this is to remove all the \r character from the file ---------------------

sed -i 's/\r$//' loop.sh

--------------------------- run jboss eap service ------------------

[root@dcyfolywb30052 ~]# systemctl daemon-reload

[root@dcyfolywb30052 ~]# systemctl stop jboss-eap-rhel

[root@dcyfolywb30052 ~]# systemctl start jboss-eap-rhel

Tuesday, March 21, 2023

IIS and .Net Core

iis-processes-asp-net-core-http-request.html

How IIS Processes ASP.NET Core HTTP Request

September 30,2020 • Development

Table of Content

Have you ever wondered what happens under the hood when you make an API call to your ASP.NET Core application hosted in IIS? Your request is passed through 2 pipelines in IIS and ASP.NET Core to be processed before returning the response. This article explains how your request is processed and how you can use it to add more functionalities to your ASP.NET Core applications.

HTTP pipeline

According to Microsoft documentation about IIS architecture, the HTTP request is picked up from the kernel mode, passed to the user mode for processing that results in a new IIS worker process (w3wp.exe) serving that HTTP request. Here are the steps:

When a client browser initiates an HTTP request for a resource on the webserver, HTTP.sys intercepts the request
HTTP.sys contacts the WAS to obtain information from the configuration store
WAS requests configuration information from the configuration store, applicationHost.config
The WWW Service receives configuration information, such as application pool and site configuration
The WWW Service uses the configuration information to configure HTTP.sys
WAS starts a worker process for the application pool to which the request was made
The worker process processes the request and returns a response to HTTP.sys
The client receives a response

Source: Introduction to IIS Architecture - Microsoft documentation

After step 6, your ASP.NET core code is executed by either the IIS worker process itself or by a Kestrel server. The HTTP response is returned to HTTP.sys once done processing. HTTP.sys then returns to the client browser.

Microsoft uses ASP.NET Core Module, a native IIS module, to plug into the pipeline to either host your ASP.NET Core app inside the IIS worker process (in-process hosting model) or to forward HTTP requests to a backend ASP.NET Core app running the Kestrel server (out-of-process hosting model).

In-process hosting model

The in-process hosting model is the default hosting model for all apps built with ASP.NET Core 2.2 or later. In the in-process hosting model, what ASP.NET Core Module does is to load the CoreCLR and calls the Program.Main method to bootstrap your app’s logic. It then handles the lifetime of the IIS native request.

Source: Host ASP.NET Core on Windows with IIS - Microsoft documentation

From the above diagram, it is clear that your app’s logic takes in the HttpContext produced by IISHttpServer which is responsible for converting the native HTTP request to managed before passing the ASP.NET Core middleware pipeline.
The middleware pipeline handles the request and passes it on as an HttpContext instance to your app’s logic.
The IISHttpServer passes your app’s response back to IIS which then forwards it back to the client initiating the request.

All of this happens right in the same IIS worker process, so the best performance is achieved.

Make sure to call the UseIIS method when configuring your application, and to explicitly specify the in-process hosting model in the web.config file as below:

<system.webServer>
<aspNetCore processPath="dotnet" hostingModel="InProcess" />
</system.webServer>

To verify, check the response header to make sure it’s Microsoft-IIS, not Kestrel.

Out-of-process hosting model

Unlike the in-process hosting model, in the out-of-process hosting model, your app’s logic runs in a dotnet.exe process separate from the IIS worker process as follows:

Source: Host ASP.NET Core on Windows with IIS - Microsoft documentation

The ASP.NET Core Module handles the dotnet.exe process management and forwards the HTTP request to the Kestrel server.
The Kestrel server picks up the request from ASP.NET Core Module to forward into the ASP.NET Core middleware pipeline.
The middleware pipeline handles the request and passes it on as an HttpContext instance to your app’s logic.
The Kestrel receives the app’s response to pass back to IIS which forwards it back to the client initiating the request.

To deploy your application using an out-of-process hosting model, specify it in your web.conf file as below:

<system.webServer>
<aspNetCore processPath="dotnet" hostingModel="OutOfProcess" />
</system.webServer>
Check the response header, it should be Kestrel.

ASP.NET core middleware pipeline

Once the request is passed to your app’s logic as an HttpContext instance, it undergoes the ASP.NET Core middleware pipeline as depicted in the below diagram where you write custom code to handle the request and return your expected response.

Source: ASP.NET Core Middleware - Microsoft documentation

Middleware is a software component that can be written and plugged into the pipeline for processing your app’s logic before or after passing the request to the next component.

Many built-in middleware components are ready to use. Understanding what they are for and their orders to use is important.

References

Reagan Templin, Introduction to IIS Architecture, www.docs.microsoft.com, 2007.
Host ASP.NET Core on Windows with IIS, www.docs.microsoft.com, 2020.
Tom Dykstra, Rick Strahl, Chris Ross, Rick Anderson, Sourabh Shirhatti, and Justin Kotalik, ASP.NET Core Module, www.docs.microsoft.com, 2020.
Rick Anderson and Steve Smith, ASP.NET Core Middleware, www.docs.microsoft.com, 2020.

original source: https://www.tutorialspoint.com/what-is-kestrel-and-how-does-it-differ-from-iis-asp-net

What is Kestrel and how does it differ from IIS? (ASP.NET)

Kestrel is a lightweight, cross-platform, and open-source web server for ASP.NET Core. It is included and enabled by default in ASP.NET Core. Kestrel is supported on all platforms and versions supported by .NET Core.

In the Program class, the ConfigureWebHostDefaults() method configures Kestrel as the web server for the ASP.NET Core application.

public class Program{
   public static void Main(string[] args){
      CreateHostBuilder(args).Build().Run();
   }

   public static IHostBuilder CreateHostBuilder(string[] args) =>
      Host.CreateDefaultBuilder(args)
         .ConfigureWebHostDefaults(webBuilder =>{
            webBuilder.UseStartup<Startup>();
         });
}

Though Kestrel can serve an ASP.NET Core application on its own, Microsoft recommends using it along with a reverse proxy such as Apache, IIS, or Nginx for better performance, security, and reliability.

The main difference between IIS and Kestrel is that Kestrel is a cross-platform server. It runs on Linux, Windows, and Mac, whereas IIS is Windows-specific.

Another essential difference between the two is that Kestrel is fully open-source, whereas IIS is closed-source and developed and maintained only by Microsoft.

IIS is an old, albeit powerful software. With Kestrel, Microsoft started with cross-platform and high performance as explicit design goals. Since the Kestrel codebase started from scratch, it allowed developers to ignore the legacy/compatibility issues and focus on speed and efficiency.

However, Kestrel doesn’t provide all the rich functionality of a full-fledged web server such as IIS, Nginx, or Apache. Hence, we typically use it as an application server, with one of the above servers acting as a reverse proxy.

Sunday, March 19, 2023

VM ware

Overview of Networking Modes

Thursday, March 2, 2023

code signing and ssl

"C:\Programs\jdk1.8.0_121\bin\keytool" -genkey -alias server -keyalg RSA -keysize 2048 -keystore dshsapoly3uat01.jks -dname "CN=dshsapoly3uat01.dshs.wa.lcl, OU=CATS, O=DSHS, L=Olympia, ST=WA, C=US"

"C:\Programs\jdk1.8.0_121\bin\keytool" -certreq -alias server -file dshsapoly3uat01.csr -keystore dshsapoly3uat01.jks

"C:\Programs\jdk1.8.0_121\bin\keytool" -import -trustcacerts -alias dshsapoly3uat01 -file dshsapoly3uat01.cer -keystore application.keystore

------------------------------------------------------------------------------------------------------------------------

"C:\Programs\jdk1.8.0_121\bin\keytool" -genkey -alias server -keyalg RSA -keysize 2048 -keystore dshsapoly3uat02.jks -dname "CN=dshsapoly3uat02.dshs.wa.lcl, OU=CATS, O=DSHS, L=Olympia, ST=WA, C=US"

"C:\Programs\jdk1.8.0_121\bin\keytool" -certreq -alias server -file dshsapoly3uat02.csr -keystore dshsapoly3uat02.jks

"C:\Programs\jdk1.8.0_121\bin\keytool" -v -list -keystore dshsapoly3uat01.jks

keytool -delete -alias server -keystore application.keystore -storepass password

"C:\Programs\jdk1.8.0_121\bin\keytool" -import -trustcacerts -alias server -file dshsapoly3uat01.cer -keystore dshsapoly3uat01.jks

--------------------------------------------------------------------------------------------------------------------------

// how to create key and request file

set OPENSSL_CONF=C:\Admin\OpenSSL\bin\openssl.cnf

openssl genrsa -out C:\Admin\certopenssl\dshsapoly3uat01.key 2048

openssl req -new -sha256 -key C:\Admin\certopenssl\dshsapoly3uat01.key -out C:\Admin\certopenssl\dshsapoly3uat01.csr

openssl req -noout -text -in C:\Admin\certopenssl\dshsapoly3uat01.csr

openssl pkcs12 -export -out C:\Programs\wildfly-10.1.0.Final\domain-host1\configuration\dshsapoly3uat01.pfx -inkey C:\Programs\wildfly-10.1.0.Final\domain-host1\configuration\dshsapoly3uat01.key -in C:\Programs\wildfly-10.1.0.Final\domain-host1\configuration\dshsapoly3uat01.cer

"C:\Programs\jdk1.8.0_121\bin\keytool" -importkeystore -srckeystore dshsapoly3uat01.pfx -srcstoretype pkcs12 -destkeystore dshsapoly3uat01.jks -deststoretype JKS

"C:\Programs\jdk1.8.0_121\bin\keytool" -v -list -keystore dshsapoly3flp01.jks

openssl pkcs12 -export -in C:\Programs\wildfly-10.1.0.Final\domain-host1\configuration\dshsapoly3uat01.cer -out C:\Programs\wildfly-10.1.0.Final\domain-host1\configuration\dshsapoly3uat01.p12

-------------------------------------------------------------------------------------------------------------

// how to create key and request file for code signing certificate

openssl req -new -newkey rsa:2048 -keyout C:\Admin\certs\ocx\codesign\eWiSACWISCodeSign.key -sha256 -nodes -out C:\Admin\certs\ocx\codesign\eWiSACWISCodeSign.csr -config codesign.cnf

// how to generate self sign certificate

openssl x509 -req -days 365 -in C:\Admin\certs\ocx\codesign\eWiSACWISCodeSign1.csr -signkey C:\Admin\certs\ocx\codesign\eWiSACWISCodeSign1.key -sha256 -out C:\Admin\certs\ocx\codesign\eWiSACWISCodeSign1.cer

// code sign ocx, exe, cab, etc

Signtool sign /debug /f eWiSACWIS.pfx /p changeit /t http://timestamp.digicert.com SacwisDocumentAutomation.ocx

signtool verify /a SacwisDocumentAutomation.ocx

============================ codesign.cnf ==================================

[ req ]

default_bits = 2048 # RSA key size

encrypt_key = yes # Protect private key

default_md = sha256 # MD to use

utf8 = yes # Input is UTF-8

string_mask = utf8only # Emit UTF-8 strings

prompt = yes # Prompt for DN

distinguished_name = codesign_dn # DN template

req_extensions = codesign_reqext # Desired extensions

[ codesign_dn ]

commonName = Department of Social and Health Services

commonName_max = 64

[ codesign_reqext ]

keyUsage = critical,digitalSignature

extendedKeyUsage = critical,codeSigning

subjectKeyIdentifier = hash

=====================================================================

---------------------------------------------------------

// how to create key and request file

// first of all, download openssl tool and save it somewhere on the machine.

// steps to create key and cert request file.

set OPENSSL_CONF=C:\Admin\OpenSSL\bin\openssl.cnf

openssl genrsa -out C:\Admin\certopenssl\dshsapoly3uat01.key 2048

openssl req -new -sha256 -key C:\Admin\certopenssl\dshsapoly3uat01.key -out C:\Admin\certopenssl\dshsapoly3uat01.csr

//this command is to view the csr, not a necessary step

openssl req -noout -text -in C:\Admin\certopenssl\dshsapoly3uat01.csr

// send your csr to WaTech or any other CA and get cer files from your CA before running the following commands.

//create pfx file

// create keystore

"C:\Programs\jdk1.8.0_121\bin\keytool" -importkeystore -srckeystore dshsapoly3uat01.pfx -srcstoretype pkcs12 -destkeystore dshsapoly3uat01.jks -deststoretype JKS

// change alias if necessary

"C:\Programs\jdk1.8.0_121\bin\keytool" -changealias -alias "te-93ac6810-4331-41b9-b99a-efd06df5ec5b" -destalias "uat01" -keypass uat01pass -keystore dshsapoly3uat01.jks -storepass changed

// change private key password (keypass)

"C:\Programs\jdk1.8.0_121\bin\keytool" -keypasswd -alias uat01 -keystore dshsapoly3uat01.jks

// view your keystore file and check the alias name in the file

"C:\Programs\jdk1.8.0_121\bin\keytool" -v -list -keystore dshsapoly3flp01.jks

Tuesday, February 14, 2023

red hat linux

1. connect to network. Modify the following network interface file

RedHat rhel no internet connection after install

vi /etc/sysconfig/network-scripts/ifcfg-ens33 (network interface)

https://www.youtube.com/watch?v=Skle0U2kvtE

2. https://access.redhat.com/solutions/253273

you need to register your new server. Create account on redhat and make sure go the developer portal for no-cost redhat registration

https://developers.redhat.com/articles/faqs-no-cost-red-hat-enterprise-linux#general

https://access.redhat.com/solutions/253273

subscription-manager register --username <username> --password <password> --auto-attach

3. install GUI, run (recommended)

# yum groupinstall "Server with GUI"

or For RHEL 7 Server you can target the "Server with GUI" group instead

# yum groupinstall "Server with GUI"

After installing the appropriate packages, change the default systemd boot target to graphical.target. If you run into any errors, try updating the system first with 'yum update'.

systemctl set-default graphical.target

To immediately switch to the GUI login, start the graphical.target:

systemctl isolate graphical.target

change the resolution in rhel applications -> system tool -> setting -> devices -> displays ->resolution

4 . mount to shared drive from windows

https://www.youtube.com/watch?v=b14pq04jtDg

install samba protocol

sudo yum -y install samba-client samba-common cifs-utils

create a mapped folder

sudo mkdir -p /mnt/sharedfolder

sudo mount.cifs -v //WINBOX01/shared /mnt/winbox01 --verbose -o user=brainstrust,password=topsecret,domain=WINBOX01

check the mapped folder

df -kh

5. sudo yum install java-1.8.0-openjdk-devel

6. sudo yum install firefox

7. sudo -i -- to change to root

8. su -l user or exit to the user you have logged in with

9. /etc/ssh/sshd_config to open ssh port 22 (or others)

10. su root (switch to root)

Username is not in the sudoers file

11. edit /etc/sudoers

Let’s add a line under the user privilege specification. Its purpose is to grant the system user the mentioned superuser privileges:

# User privilege specification
root	ALL=(ALL:ALL) ALL
francis  ALL=(ALL:ALL) ALL

Now francis can perform tasks that require root access.

Shortly after making the change, we need to save these changes and exit from the text editor. To do this, we’ll press the keyboard keys CTRL+X to exit, Y to save, and Enter to submit. Finally, we can exit from the root session.

12. Adding the Username to the sudo GroupAs in the solution above, it’s important that we first switch to the root user:

$ su root
Password:

The su command allows us to perform tasks with the permissions of another user, which in this case is root.

13. Next, we’ll show the contents of the sudoers file. We’ll focus on the lines that declare the privileges of users, as well as those of user groups:

# cat /etc/sudoers
...

# User privilege specification
root	ALL=(ALL:ALL) ALL

# Members of the admin group may gain root privileges
%admin ALL=(ALL) ALL

# Allow members of group sudo to execute any command
%sudo	ALL=(ALL:ALL) ALL

...

As shown above, the root user and the members of the admin and sudo groups have superuser privileges. Then again, the sudo group is present, since we’re in a Debian-based distribution. In a Red Hat-based Linux distribution, we’ll encounter the wheel user group instead. It’s the equivalent of the sudo user group for Red Hat-based distributions.

Now, since we’re operating in Debian, let’s add our user to the sudo group:

# usermod -aG sudo francis

Here, the usermod command allows us to modify our user’s attributes. In particular, we use the -G option to declare that we’d like to update the group information for our user francis. Also, the -a option makes certain that other groups associated with this user aren’t deleted in the process. As a result, francis can now perform administrative tasks with sudo. In Red Hat distros, replacing sudo with wheel provides similar results.

Once we’re through, we’ll exit from the root user session:

# exit
exit

Now we’re back to our previous user session.

rm -r -f * (silently delete subfolders and files)