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Existing HTTP is not in the kernel. If you want to speak HTTP, you already need a library. With existing HTTP, that library needs to handle portability concern

Existing HTTP is not in the kernel. If you want to speak HTTP, you already need a library. With existing HTTP, that library needs to handle portability concerns to use TCP on different operating systems. With new HTTP, the library will need to do the same thing but with UDP. Seems like the complexity is no higher, just a difference (TCP vs. UDP) in how your library will interface with the platform network stack API.

dogma1138 8y ago
Http is done in kernel on Windows http.sys is a kernel driver which IIS and some other windows servers use. Some UNIX distros also have their kernel implementation, and Linux has/had TUX but I’m not sure if it’s in use anywhere.
- ComputerGuru 8y ago
  http.sys is strictly for listening for inbound connections and not a general purpose HTTP API. Amongst other things, it lets multiple applications listen to port 80 on Windows. Didn't read through this article the whole way, but it was the first I found to share that seemed to give a good overview: https://www.codeproject.com/articles/437733/demystify-http-sys-with-httpsysmanager https://www.codeproject.com/articles/437733/demystify-http-s...
  - dogma1138 8y ago
    Yes, http.sys is an http server implemented in the Windows Kernel it’s the http server IIS and all other http based windows services use and has an API for 3rd party servers. https://docs.microsoft.com/en-us/iis/get-started/introduction-to-iis/introduction-to-iis-architecture#hypertext-transfer-protocol-stack-httpsys https://docs.microsoft.com/en-us/iis/get-started/introductio... The point being that there are advantages to implementing a kernel or hybrid mode HTTP server and Microsoft has done it on Windows some other implementations exist but other than MF/Big Unix I’ve never seen them in actual use. I don’t think there is much of a point of implementing an HTTP client library in the kernel tho since the performance should be an issue really on the client side.
    - mentat 8y ago
      The history of IIS vulnerabilities with in kernel execution and the time it takes to get comprehensive patching seem like pretty substantial disadvantages.
      - dogma1138 8y ago
        I don’t necessarily disagree that there are disadvantages as well that said I got by far more often root on boxes due to core server or application level vulns on Linux machines than system on Windows boxes through an IIS vuln (app vulns are still a problem as well as running your worker services as privileged users but that isn’t related to http.sys) since those are more often than not patched.

dogma1138 8y ago

Http is done in kernel on Windows http.sys is a kernel driver which IIS and some other windows servers use. Some UNIX distros also have their kernel implementation, and Linux has/had TUX but I’m not sure if it’s in use anywhere.

ComputerGuru 8y ago
http.sys is strictly for listening for inbound connections and not a general purpose HTTP API. Amongst other things, it lets multiple applications listen to port 80 on Windows. Didn't read through this article the whole way, but it was the first I found to share that seemed to give a good overview: https://www.codeproject.com/articles/437733/demystify-http-sys-with-httpsysmanager https://www.codeproject.com/articles/437733/demystify-http-s...
- dogma1138 8y ago
  Yes, http.sys is an http server implemented in the Windows Kernel it’s the http server IIS and all other http based windows services use and has an API for 3rd party servers. https://docs.microsoft.com/en-us/iis/get-started/introduction-to-iis/introduction-to-iis-architecture#hypertext-transfer-protocol-stack-httpsys https://docs.microsoft.com/en-us/iis/get-started/introductio... The point being that there are advantages to implementing a kernel or hybrid mode HTTP server and Microsoft has done it on Windows some other implementations exist but other than MF/Big Unix I’ve never seen them in actual use. I don’t think there is much of a point of implementing an HTTP client library in the kernel tho since the performance should be an issue really on the client side.
  - mentat 8y ago
    The history of IIS vulnerabilities with in kernel execution and the time it takes to get comprehensive patching seem like pretty substantial disadvantages.
    - dogma1138 8y ago
      I don’t necessarily disagree that there are disadvantages as well that said I got by far more often root on boxes due to core server or application level vulns on Linux machines than system on Windows boxes through an IIS vuln (app vulns are still a problem as well as running your worker services as privileged users but that isn’t related to http.sys) since those are more often than not patched.