The server waits on an incoming connection on port number , and when one arrives, it hands the socket for the connection to a newly initiated thread for processing this is a common pattern for servers which do significant work for each new socket. Like the client, it is a console application, so it displays progress on the console. If you run a debug build and attach a debugger, there's also a lot of detailed output. Once a thread is initiated, it waits for the client at the other end of the socket to initiate an SSL handshake or until it eventually times out.
As part of the handshake, the client will use SNI to tell the server what server name it is trying to connect to, and armed with that information, each thread will look for an appropriately named certificate in the machine store subsequent connections requesting the same host name use the same certificate. The chosen certificate must meet other requirements too, such as having a private key and being marked as usable for server identification.
The server requests a certificate from the client and validates that before marking the connection as successful. The server has a bit of code at the end to automatically initiate a couple of client instances, one connecting to the server name "localhost" the other is just allowed to default to the local host name. This makes testing a bit easier and allows you to see certificates being selected or created.
Most of the code compiles under Visual Studio , , and , but when I added the SAN and wildcard certificate matching, I used modern code, requiring at least VS, and upgraded the project to use the VS version toolchain, the September version uses VS the version toolchain but could be compiled with VS with minor changes.
It is a 32 bit Unicode build, in that release there is no ANSI alternative although the sample data transferred is a byte stream. I'd expect it to run on any Windows version beyond Windows Vista. The July updates include an optional 64 bit build and the August version 2. The Unicode interfaces are unchanged. The source uses some ATL utility functions and classes but neither the client nor the server use the ATL framework as a whole. In production environments, you would get a certificate from a trusted authority a "Certificate Authority" or CA.
The CA would be responsible for ensuring that you were authorized to request the certificate you asked for. For example, if you were requesting a server certificate for SSL, the CA would ensure you were the owner of the domain the server was in. Such a certificate would usually identify the server by its fully qualified domain name, something like hostname. If a random person asks for a certificate in the "microsoft. Although mistakes do occasionally happen, they are rare and you can generally trust certificates issued by a legitimate CA.
Each certificate has many attributes, but the ones of most importance for SSL are the "Subject Name" what entity the certificate is for, like a specific server or a particular user , the "Key Usage" and "Enhanced Key Usage" describing how the certificate is intended to be used "Server Authentication" for example , and whether you have a private key for the certificate or just a public one.
Other attributes like the validity period or issuer name don't matter much in this sample, but would in production because then you'd care about who issued the certificate and whether it was currently valid. Client certificates usually identify a particular user, so they often have an e-mail address as a subject name. Newer certificate standards allow for a Subject Alternative Name SAN on each certificate, which allows the same certificate to be used for a list of names.
Another way of allowing for multiple names is "wildcard" certificates, which allow multiple servers in the same domain to be protected by the same certificate. For test purposes, you don't need CA issued certificates; you can use ones you generate yourself so-called "self signed certificates". For the client end, this sample code will use any certificate with a private key it can find, or make one if it has to.
The client application is called StreamClient and the basic flow it uses is fairly simple:. If all you need is a straightforward client and you are not too concerned with the details of SSL or TCP, just read "Main Program" below, then skip forward to Server Details if you need a server too. IT Management.
Project Management. Resources Blog Articles. Menu Help Create Join Login. Get Updates. Get project updates , sponsored content from our select partners, and more.
Full Name. Phone Number. Job Title. Building intelligent escalation chains for modern SRE. Podcast Who is building clouds for the independent developer? Featured on Meta. Now live: A fully responsive profile. Reducing the weight of our footer. Linked Related Hot Network Questions.
Question feed. Stack Overflow works best with JavaScript enabled. Accept all cookies Customize settings. PS5 restock updates. Black Friday deals. Windows Windows. Most Popular. New Releases. Desktop Enhancements. Networking Software. Trending from CNET. Download Now. Developer's Description By thegrapevine. The program can be quickly and easily installed on the computer, thanks to the fact that there are no special options involved in the setup phase.
Once you edit these properties and choose the preferred protocol from a drop-down menu, you can start connecting with one click. Enabling the proxy is optional. The program has direct connection support.
0コメント