apt-key - APT key management utility
apt-key [--keyring filename] {add filename | del keyid | export keyid | exportall | list | finger | adv | update | net-update | {-v | --version} | {-h | --help}}
apt-key is used to manage the list of keys used by apt to authenticate packages. Packages which have been authenticated using these keys will be considered trusted. Note that if usage of apt-key is desired the additional installation of the GNU Privacy Guard suite (packaged in gnupg) is required. For this reason alone the programmatic usage (especially in package maintainerscripts!) is strongly discouraged. Further more the output format of all commands is undefined and can and does change whenever the underlying commands change. apt-key will try to detect such usage and generates warnings on stderr in these cases.
apt-key supports only the binary OpenPGP format (also known as "GPG key public ring") in files with the "gpg" extension, not the keybox database format introduced in newer gpg(1) versions as default for keyring files. Binary keyring files intended to be used with any apt version should therefore always be created with gpg --export. Alternatively, if all systems which should be using the created keyring have at least apt version >= 1.4 installed, you can use the ASCII armored format with the "asc" extension instead which can be created with gpg --armor --export.
add filename Add a new key to the list of trusted keys. The key is read from the filename given with the parameter filename or if the filename is - from standard input. It is critical that keys added manually via apt-key are verified to belong to the owner of the repositories they claim to be for otherwise the apt-secure(8) infrastructure is completely undermined. Note: Instead of using this command a keyring should be placed directly in the /etc/apt/trusted.gpg.d/ directory with a descriptive name and either "gpg" or "asc" as file extension. del keyid Remove a key from the list of trusted keys. export keyid Output the key keyid to standard output. exportall Output all trusted keys to standard output. list, finger List trusted keys with fingerprints. adv Pass advanced options to gpg. With adv --recv-key you can e.g. download key from keyservers directly into the the trusted set of keys. Note that there are no checks performed, so it is easy to completely undermine the apt-secure(8) infrastructure if used without care. update (deprecated) Update the local keyring with the archive keyring and remove from the local keyring the archive keys which are no longer valid. The archive keyring is shipped in the archive-keyring package of your distribution, e.g. the ubuntu-keyring package in Ubuntu. Note that a distribution does not need to and in fact should not use this command any longer and instead ship keyring files in the /etc/apt/trusted.gpg.d/ directory directly as this avoids a dependency on gnupg and it is easier to manage keys by simply adding and removing files for maintainers and users alike. net-update Perform an update working similarly to the update command above, but get the archive keyring from a URI instead and validate it against a master key. This requires an installed wget(1) and an APT build configured to have a server to fetch from and a master keyring to validate. APT in Debian does not support this command, relying on update instead, but Ubuntu's APT does.
Note that options need to be defined before the commands described in the previous section. --keyring filename With this option it is possible to specify a particular keyring file the command should operate on. The default is that a command is executed on the trusted.gpg file as well as on all parts in the trusted.gpg.d directory, though trusted.gpg is the primary keyring which means that e.g. new keys are added to this one.
/etc/apt/trusted.gpg Keyring of local trusted keys, new keys will be added here. Configuration Item: Dir::Etc::Trusted. /etc/apt/trusted.gpg.d/ File fragments for the trusted keys, additional keyrings can be stored here (by other packages or the administrator). Configuration Item Dir::Etc::TrustedParts.
apt-get(8), apt-secure(8)
APT bug page[1]. If you wish to report a bug in APT, please see /usr/share/doc/debian/bug-reporting.txt or the reportbug(1) command.
APT was written by the APT team <apt@packages.debian.org>.
Jason Gunthorpe APT team
1. APT bug page http://bugs.debian.org/src:apt
Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.
Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.
Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.
Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.
The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.
Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.
Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.
Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.