Hírolvasó

OpenSMTPD table protocol changes, now with the backstory

1 év 4 hónap óta
Regular readers will be aware that OpenBSD ships with its own mail server implementation, OpenSMTPD, in its base system.

In a recent message to the tech@ mailing list, Omar Polo (op@) asked for comments or oks for a patches implementing a change of table protocols. A little later, Gilles Chehade (gilles@) posted to the misc@opensmtpd.org mailing list with the backstory for this change.

The message follows in full below (apparently the otherwise fine marc.info archive site no longer archives the list):

Date: Fri, 03 May 2024 08:22:03 +0000 From: gilles@poolp.org To: misc@opensmtpd.org Subject: smtpd: change the table protocol Hello, This is a copy of a mail I sent to OpenBSD hackers a few days ago so you are aware of work being done on OpenSMTPD by Omar Polo. ~~~ TL;DR: proposal to change table backends wire protocol to one that's closer to filters, it has proven to work for years now, comes with many benefits and it is a very trivial change that we can pull in a handful of hours: https://tmp.omarpolo.com/smtpd-tables.7.html

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Harald Welte: OsmoDevCon 2024: "High-performance I/O using io_uring via osmo_io"

1 év 4 hónap óta

I've co-presented a talk (together with Andreas Eversberg High-performance I/O using io_uring via osmo_io as part of the OsmoDevCon 2024 conference on Open Source Mobile Communications.

Traditional socket I/O via read/write/recvfrom/sendto/recvmsg/sendmsg and friends creates a very high system call load. A highly-loaded osmo-bsc spends most of its time in syscall entry and syscall exit.

io_uring is a modern Linux kernel mechanism to avoid this syscall overhead. We have introduced the osmo_io`API to libosmocore as a generic back-end for non-blocking/asynchronous I/O and a back-end for our classic `osmo_fd / poll approach as well as a new backend for io_uring.

The talk will cover

  • a very basic io_uring introduction

  • a description of the osmo_io API

  • the difficulties porting from osmo_fd to osmo_io

  • status of porting various sub-systems over to osmo_io

You can find the video recording at https://media.ccc.de/v/osmodevcon2024-209-high-performance-i-o-using-iouring-via-osmoio

[$] Inheritable credentials for directory file descriptors

1 év 4 hónap óta
In Unix-like systems, an open file descriptor carries the right to access the opened object in specific ways. As a general rule, that file descriptor does not enable access to any other objects. The recently merged BPF token feature runs counter to this practice by creating file descriptors that carry specific BPF-related access rights. A similar but different approach to capability-carrying file descriptors, in the form of directory file descriptors that include their own credentials, is currently under consideration in the kernel community.
corbet

Rust 1.78.0 released

1 év 4 hónap óta
Version 1.78.0 of the Rust language has been released. Changes include a new mechanism for diagnostic attributes, changes to how assertions around unsafe blocks are handled, and more.

Rust now supports a #[diagnostic] attribute namespace to influence compiler error messages. These are treated as hints which the compiler is not required to use, and it is also not an error to provide a diagnostic that the compiler doesn't recognize. This flexibility allows source code to provide diagnostics even when they're not supported by all compilers, whether those are different versions or entirely different implementations.

corbet

Security updates for Thursday

1 év 4 hónap óta
Security updates have been issued by Debian (chromium and distro-info-data), Fedora (et, php-tcpdf, python-aiohttp, python-openapi-core, thunderbird, tpm2-tools, and tpm2-tss), Red Hat (nodejs:16 and podman), and Ubuntu (firefox).
jake