Some more tips for interacting\nwith the namespaces\nof Podman containers.
\n"}, {"id": "http://www.gabriel.urdhr.fr/2022/12/03/entering-podman-namespaces/", "title": "Entering in Podman containers", "url": "https://www.gabriel.urdhr.fr/2022/12/03/entering-podman-namespaces/", "date_published": "2022-12-03T00:00:00+01:00", "date_modified": "2022-12-03T00:00:00+01:00", "tags": ["computer", "linux", "system", "podman", "container", "security"], "content_html": "Some commands for interacting with the namespaces\nof Podman containers.
\n"}, {"id": "http://www.gabriel.urdhr.fr/2021/05/08/tuntap/", "title": "TUN/TAP interface (on Linux)", "url": "https://www.gabriel.urdhr.fr/2021/05/08/tuntap/", "date_published": "2021-05-08T00:00:00+02:00", "date_modified": "2021-05-08T00:00:00+02:00", "tags": ["computer", "system", "network", "tun", "tap", "linux", "vpn"], "content_html": "Some notes about using the TUN/TAP interface, especially on Linux.
\n"}, {"id": "http://www.gabriel.urdhr.fr/2021/03/17/frida-disable-certificate-check-on-android/", "title": "Disable certificate verification on Android with Frida", "url": "https://www.gabriel.urdhr.fr/2021/03/17/frida-disable-certificate-check-on-android/", "date_published": "2021-03-17T00:00:00+01:00", "date_modified": "2021-03-17T00:00:00+01:00", "tags": ["computer", "system", "security", "android", "frida", "tls", "reverse-engineering"], "content_html": "Some notes about how to write a Frida script\nwith the (somewhat classic) example of disabling certificate verification\nfor TLS communications on Android applications.
\n"}, {"id": "http://www.gabriel.urdhr.fr/2020/04/20/linux-host-name-resolution/", "title": "GNU/Linux host name resolution", "url": "https://www.gabriel.urdhr.fr/2020/04/20/linux-host-name-resolution/", "date_published": "2020-04-20T00:00:00+02:00", "date_modified": "2020-04-20T00:00:00+02:00", "tags": ["computer", "network", "dns", "system"], "content_html": "This post describes different software components\ninvolved in host name resolutions and DNS configuration on GNU/Linux systems.\nIt consists of a diagram and some accompanying explanations.\nThe goal is to give some pointers and references to understand\nhow to troubleshoot host name/DNS resolution problems\nand configuration problems on GNU/Linux systems.
\n"}, {"id": "http://www.gabriel.urdhr.fr/2016/08/07/openssh-proxyusefdpass/", "title": "OpenSSH ProxyUseFdPass", "url": "https://www.gabriel.urdhr.fr/2016/08/07/openssh-proxyusefdpass/", "date_published": "2016-08-07T00:00:00+02:00", "date_modified": "2025-03-28T15:37:22+01:00", "tags": ["computer", "network", "system", "ssh", "python", "unix"], "content_html": "While looking at the OpenSSH ssh_config manpage, I found the\nProxyUseFdpass configuration I did not know about.\nIt is apparently not widely known or used.
Some notes on the ELF \ud83e\udddd file format with references, explanations and\nsome examples.
\n"}, {"id": "http://www.gabriel.urdhr.fr/2015/09/01/simgrid-mc-rewrite/", "title": "SimGridMC: The Big Split (and Cleanup)", "url": "https://www.gabriel.urdhr.fr/2015/09/01/simgrid-mc-rewrite/", "date_published": "2015-09-01T00:00:00+02:00", "date_modified": "2015-09-01T00:00:00+02:00", "tags": ["computer", "simgrid", "system"], "content_html": "In my previous SimGrid post, I\ntalked about different solutions for a better isolation between the\nmodel-checked application and the model-checker. We chose to avoid\nthe (hackery) solution based multiple dynamic-linker namespaces in the\nsame process and use a more conventional process-based isolation.
\n"}, {"id": "http://www.gabriel.urdhr.fr/2015/05/29/core-file/", "title": "Anatomy of an ELF core file", "url": "https://www.gabriel.urdhr.fr/2015/05/29/core-file/", "date_published": "2015-05-29T00:00:00+02:00", "date_modified": "2015-05-29T00:00:00+02:00", "tags": ["computer", "system", "elf", "coredump"], "content_html": "The Executable and Linkable Format (ELF) \ud83e\udddd is used for\ncompilation outputs (.o files), executables, shared libraries and core dumps.\nThe first cases are documented in the System V ABI\nspecification\nand the Tools Interface Standard (TIS) ELF\nspecification but there does not\nseem to be much documentation about the usage of the ELF format for core dumps.\nHere are some notes on this.
A short summary of the logging message workflow with\nsystemd-journald\n(and the different formats and sockets involved).
\n"}, {"id": "http://www.gabriel.urdhr.fr/2015/01/22/elf-linking/", "title": "ELF loading and dynamic linking", "url": "https://www.gabriel.urdhr.fr/2015/01/22/elf-linking/", "date_published": "2015-01-22T00:00:00+01:00", "date_modified": "2015-01-22T00:00:00+01:00", "tags": ["computer", "system", "elf", "linker", "linux", "multiarch"], "content_html": "Some notes on ELF \ud83e\udddd loading and dynamic linking mainly for GNU userland\n(ld.so, libc, libdl) running on top of the Linux kernel. Some\nprior knowlegde on the topic (virtual memory, shared objects,\nsections) might be useful to understand this.
Today, I managed to forget a password but I had a Icedove (Thunderbird) process\nrunning containing the password.
\n"}, {"id": "http://www.gabriel.urdhr.fr/2015/01/06/simgrid-mc-isolation/", "title": "Better isolation for SimGridMC", "url": "https://www.gabriel.urdhr.fr/2015/01/06/simgrid-mc-isolation/", "date_published": "2015-01-06T00:00:00+01:00", "date_modified": "2015-01-06T00:00:00+01:00", "tags": ["simgrid", "system", "computer", "linker", "linux", "simulation", "elf"], "content_html": "In an attempt to simplify the development around the SimGrid\nmodel-checker, we were thinking about moving the model-checker out in\na different process. Another different approach would be to use a\ndynamic-linker isolation of the different components of the process.\nHere is a summary of the goals, problems and design issues surrounding\nthese topics.
\n"}, {"id": "http://www.gabriel.urdhr.fr/2014/07/22/same-page-merging/", "title": "Results on same-page-merging snapshots", "url": "https://www.gabriel.urdhr.fr/2014/07/22/same-page-merging/", "date_published": "2014-07-22T00:00:00+02:00", "date_modified": "2014-07-22T00:00:00+02:00", "tags": ["simgrid", "system", "computer", "checkpoint"], "content_html": "In the previous episode, I talked about the\nimplementation of a same-page-merging page store. On top of this, we\ncan build same-page-merging snapshots for the SimGrid model checker.
\n"}, {"id": "http://www.gabriel.urdhr.fr/2014/06/13/page-store/", "title": "Page store for the Simgrid model checker", "url": "https://www.gabriel.urdhr.fr/2014/06/13/page-store/", "date_published": "2014-06-13T00:00:00+02:00", "date_modified": "2014-06-13T00:00:00+02:00", "tags": ["simgrid", "system", "computer", "checkpoint"], "content_html": "The first (lower) layer of the per-page snapshot mechanism is a page\nstore: its responsibility is to store immutable shareable\nreference-counted memory pages independently of the snapshoting\nlogic. Snapshot management and representation, soft-dirty tracking\nwill be handled in higher layer.
\n"}, {"id": "http://www.gabriel.urdhr.fr/2014/06/03/non-cow-snapshots/", "title": "Per-page shallow snapshots for the SimGrid model checker", "url": "https://www.gabriel.urdhr.fr/2014/06/03/non-cow-snapshots/", "date_published": "2014-06-03T00:00:00+02:00", "date_modified": "2014-06-03T00:00:00+02:00", "tags": ["simgrid", "system", "computer", "checkpoint"], "content_html": "I looked at my options to achieve efficient/cheap snapshots of the\nsimulated application for the Simgrid model checker using\ncopy-on-write. Here I look at another\nsolution to achieve this without using copy-on-write.
\n"}, {"id": "http://www.gabriel.urdhr.fr/2014/06/02/cow-snapshots/", "title": "Copy-on-write snapshots for the SimGrid model checker", "url": "https://www.gabriel.urdhr.fr/2014/06/02/cow-snapshots/", "date_published": "2014-06-02T00:00:00+02:00", "date_modified": "2014-06-02T00:00:00+02:00", "tags": ["simgrid", "system", "computer", "checkpoint"], "content_html": "The SimGrid model checker\nexplores the graph of possible executions of\na simulated distributed application in order to verify safety and\nliveness properties. The model checker needs to store the state of the\napplication in each node of the execution graph in order to detect\ncycles. However, saving the whole state of the application at each\nnode of the graph leads to huge memory consumption and in some\ncases most of the time is spent copying data in order to take the\nsnapshots of the application. We will see how we could solve this problem,\nusing copy-on-write.
\n"}]}