EasyPG Assistant User’s Manual
EasyPG Assistant is an Emacs user interface to GNU Privacy Guard (GnuPG, see Top in Using the GNU Privacy Guard).
EasyPG Assistant is a part of the package called EasyPG, an all-in-one GnuPG interface for Emacs. EasyPG also contains the library interface called EasyPG Library.
This file describes EasyPG Assistant 1.0.0.
Copyright © 2007–2024 Free Software Foundation, Inc.
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, with the Front-Cover Texts being “A GNU Manual,” and with the Back-Cover Texts as in (a) below. A copy of the license is included in the section entitled “GNU Free Documentation License”.
(a) The FSF’s Back-Cover Text is: “You have the freedom to copy and modify this GNU manual.”
Table of Contents
- 1 Overview
- 2 Quick Start
- 3 Commands
- 4 GnuPG Version Compatibility
- 5 GnuPG Pinentry
- 6 Caching Passphrases
- 7 Bug Reports
- Appendix A GNU Free Documentation License
- Concept Index
- Key Index
- Function Index
- Variable Index
EasyPG Assistant is an Emacs frontend application to GnuPG (GNU Privacy Guard) that provides the following features:
- Key management.
- Cryptographic operations on regions.
- Cryptographic operations on files.
- Dired integration.
- Mail-mode integration.
- Automatic encryption/decryption of *.gpg files.
2 Quick Start
You can use EasyPG Assistant without any Emacs or GnuPG configuration whatsoever, for example to encrypt and decrypt files automatically with symmetric encryption, see Encrypting and Decrypting gpg Files. However, to use the full set of EasyPG Assistant’s functions you should have at least some minimum GnuPG configuration in place.
John Michael Ashley’s GNU Privacy Handbook, available online as part of the GnuPG user guides, provides an introduction to GnuPG use and configuration. In contrast to that, the GnuPG manual (see Top in Using the GNU Privacy Guard) is more of a reference manual.
EasyPG Assistant commands are prefixed by ‘epa-’. For example,
- To browse your keyring, type M-x epa-list-keys
- To create a cleartext signature of the region, type M-x epa-sign-region
- To encrypt a file, type M-x epa-encrypt-file
- To query a key server for keys, type M-x epa-search-keys
EasyPG Assistant provides several cryptographic features which can be integrated into other Emacs functionalities. For example, automatic encryption/decryption of *.gpg files.
This chapter introduces various commands for typical use cases.
- Key Management
- Cryptographic Operations on Regions
- Cryptographic Operations on Files
- Dired Integration
- Mail-Mode Integration
- Encrypting and Decrypting gpg Files
- Querying a Key Server
3.1 Key Management
Probably the first step of using EasyPG Assistant is to browse your keyring. M-x epa-list-keys is corresponding to ‘gpg --list-keys’ from the command line.
- Command: epa-list-keys name mode ¶
Show all keys matched with name from the public keyring.
The output looks as follows.
u A5B6B2D4B15813FE Daiki Ueno <firstname.lastname@example.org>
A character on the leftmost column indicates the trust level of the key. If it is ‘u’, the key is marked as ultimately trusted. The second column is the key ID, and the rest is the user ID.
You can move over entries by TAB. If you type RET or click button1 on an entry, you will see more detailed information about the key you selected.
u Daiki Ueno <email@example.com> u A5B6B2D4B15813FE 1024bits DSA Created: 2001-10-09 Expires: 2007-09-04 Capabilities: sign certify Fingerprint: 8003 7CD0 0F1A 9400 03CA 50AA A5B6 B2D4 B158 13FE u 4447461B2A9BEA2D 2048bits ELGAMAL_E Created: 2001-10-09 Expires: 2007-09-04 Capabilities: encrypt Fingerprint: 9003 D76B 73B7 4A8A E588 10AF 4447 461B 2A9B EA2D
To browse your private keyring, use M-x epa-list-secret-keys.
- Command: epa-list-secret-keys name ¶
Show all keys matched with name from the private keyring.
In *Keys* buffer, several commands are available. The common use case is to export some keys to a file. To do that, type m to select keys, type o, and then supply the filename.
Below are other commands related to key management. Some of them take a file as input/output, and others take the current region.
- Command: epa-insert-keys keys ¶
Insert selected keys after the point. It will let you select keys before insertion. By default, it will encode keys in the OpenPGP armor format.
- Command: epa-import-keys file ¶
Import keys from file to your keyring.
- Command: epa-import-keys-region start end ¶
Import keys from the current region between start and end to your keyring.
- Command: epa-import-armor-in-region start end ¶
Import keys in the OpenPGP armor format in the current region between start and end. The difference from
epa-import-armor-in-regionsearches armors in the region and applies
epa-import-keys-regionto each of them.
- Command: epa-delete-keys allow-secret ¶
Delete selected keys. If allow-secret is non-
nil, it also delete the secret keys.
3.2 Cryptographic Operations on Regions
- Command: epa-decrypt-region start end ¶
Decrypt the current region between start and end. It replaces the region with the decrypted text.
- Command: epa-decrypt-armor-in-region start end ¶
Decrypt OpenPGP armors in the current region between start and end. The difference from
epa-decrypt-armor-in-regionsearches armors in the region and applies
epa-decrypt-regionto each of them. That is, this command does not alter the original text around armors.
- Command: epa-verify-region start end ¶
Verify the current region between start and end. It sends the verification result to the minibuffer or a popup window. It replaces the region with the signed text.
- Command: epa-verify-cleartext-in-region ¶
Verify OpenPGP cleartext blocks in the current region between start and end. The difference from
epa-verify-cleartext-in-regionsearches OpenPGP cleartext blocks in the region and applies
epa-verify-regionto each of them. That is, this command does not alter the original text around OpenPGP cleartext blocks.
- Command: epa-sign-region start end signers type ¶
Sign the current region between start and end. By default, it creates a cleartext signature. If a prefix argument is given, it will let you select signing keys, and then a signature type.
- Command: epa-encrypt-region start end recipients sign signers ¶
Encrypt the current region between start and end. It will let you select recipients. If a prefix argument is given, it will also ask you whether or not to sign the text before encryption and if you answered yes, it will let you select the signing keys.
3.3 Cryptographic Operations on Files
- Command: epa-decrypt-file file &optional output ¶
Decrypt file. If you do not specify the name output to use for the decrypted file, this function prompts for the value to use.
- Command: epa-verify-file file ¶
- Command: epa-sign-file file signers type ¶
Sign file. If a prefix argument is given, it will let you select signing keys, and then a signature type.
- Command: epa-encrypt-file file recipients ¶
Encrypt file. It will let you select recipients.
3.4 Dired Integration
EasyPG Assistant extends Dired Mode for GNU Emacs to allow users to easily do cryptographic operations on files. For example,
M-x dired (mark some files) : e (or M-x epa-dired-do-encrypt) (select recipients by 'm' and click [OK])
The following keys are assigned.
- : d ¶
Decrypt marked files.
- : v ¶
Verify marked files.
- : s ¶
Sign marked files.
- : e ¶
Encrypt marked files.
3.5 Mail-Mode Integration
EasyPG Assistant provides a minor mode
epa-mail-mode to help
user compose inline OpenPGP messages. Inline OpenPGP is a traditional
style of sending signed/encrypted emails by embedding raw OpenPGP
blobs inside a message body, not using modern MIME format.
NOTE: Inline OpenPGP is not recommended and you should consider to use PGP/MIME. See Inline OpenPGP in E-mail is bad, Mm’kay?.
epa-mail-mode is enabled, the following keys are assigned.
You can do it by C-u 1 M-x epa-mail-mode or through the Customize
interface. Try M-x customize-variable epa-global-mail-mode.
- C-c C-e C-d and C-c C-e d ¶
Decrypt OpenPGP armors in the current buffer.
- C-c C-e C-v and C-c C-e v ¶
Verify OpenPGP cleartext signed messages in the current buffer.
- C-c C-e C-s and C-c C-e s ¶
Compose a signed message from the current buffer, using your default key. With a prefix argument, select the key to use interactively.
- C-c C-e C-e and C-c C-e e ¶
Compose an encrypted message from the current buffer. By default it tries to build the recipient list from ‘to’, ‘cc’, and ‘bcc’ fields of the mail header. To include your key in the recipient list, use ‘encrypt-to’ option in ~/.gnupg/gpg.conf. This function translates recipient addresses using the
epa-mail-aliaseslist. You can also use that option to ignore specific recipients for encryption purposes.
With prefix argument, asks you to select the recipients interactively, whether to sign, and which key(s) to sign with.
3.6 Encrypting and Decrypting gpg Files
By default, every file whose name ends with .gpg will be treated as encrypted. That is, when you open such a file, the decrypted text is inserted in the buffer rather than encrypted one. Similarly, when you save the buffer to a foo.gpg file, encrypted data is written.
When you save a buffer to an encrypted file for the first time, EasyPG
Assistant presents you a list of keys in a buffer *Keys* where
you can select recipients for encryption. See Key Management, for
a description of the format of that buffer. You can streamline this
recipient selection step by customizing variables
further below in this section.
If you do not select any recipient during this step, EasyPG Assistant uses symmetric encryption. As a consequence, you have to enter the passphrase twice for every buffer save and every so often for file reads, since the GnuPG Agent caches your passphrase for file reads at least for some time, but not for buffer saves. See Caching Passphrases, for more information.
If you have created your own keypair1, you can select that as recipient, and EasyPG Assistant will use public key encryption for that file. Since GnuPG performs encryption with your public key, it does not prompt for a passphrase for the buffer save, but it will prompt for your passphrase for file reads every now and then, depending on the GnuPG Agent cache configuration.
To encrypt and decrypt files as described above EasyPG Assistant under
certain circumstances uses intermediate temporary files that contain the
plain-text contents of the files it processes. EasyPG Assistant
creates them below the directory returned by function
temporary-file-directory (see Generating Unique File Names in GNU Emacs Lisp Reference
Manual). If you want to be sure not to leave any plain-text traces,
use an encrypted file systems at least for that directory.
The file name pattern for encrypted files can be controlled by
- Variable: epa-file-name-regexp ¶
Regexp which matches filenames treated as encrypted.
You can disable this behavior with M-x epa-file-disable, and then get it back with M-x epa-file-enable.
- Command: epa-file-disable ¶
Disable automatic encryption/decryption of *.gpg files.
- Command: epa-file-enable ¶
Enable automatic encryption/decryption of *.gpg files.
epa-file will try to use symmetric encryption, aka
password-based encryption. If you want to use public key encryption
instead, do M-x epa-file-select-keys, which pops up the key
- Command: epa-file-select-keys ¶
Select recipient keys to encrypt the currently visiting file with public key encryption.
You can also change the default behavior with the variable
- Variable: epa-file-select-keys ¶
Control whether or not to pop up the key selection dialog.
For frequently visited files, it might be a good idea to tell Emacs
which encryption method should be used through file variables
(see Local Variables in Files in The Emacs
Editor). Use the
epa-file-encrypt-to local variable for this.
For example, if you want an Elisp file to be encrypted with a public key associated with an email address ‘firstname.lastname@example.org’, add the following line to the beginning of the file.
;; -*- epa-file-encrypt-to: ("email@example.com") -*-
Instead, if you want the file always (regardless of the value of the
epa-file-select-keys variable) encrypted with symmetric
encryption, change the line as follows.
;; -*- epa-file-encrypt-to: nil -*-
Other variables which control the automatic encryption/decryption behavior are below.
- Variable: epa-file-cache-passphrase-for-symmetric-encryption ¶
nil, cache passphrase for symmetric encryption. The default value is
For security reasons, this option is turned off by default and not recommended to be used. Instead, consider using the GnuPG Agent, which in many cases can do the same job, and does it in a safer way. See Caching Passphrases, for more information.
- Variable: epa-file-inhibit-auto-save ¶
nil, disable auto-saving when opening an encrypted file. The default value is
3.7 Querying a Key Server
epa-search-keys command can be used to query a
GPG key server. Emacs will then pop up a buffer that lists
the matches, and you can then fetch (and add) keys to your personal
In the key search buffer, you can use the f command to mark keys for fetching, and then x to fetch the keys (and incorporate them into your key ring).
epa-keyserver variable says which server to query.
4 GnuPG Version Compatibility
As of June 2023, there are three active branches of GnuPG: 2.4, 2.2, and 1.4. GnuPG versions 2.4.1 and later suffer from GnuPG bug T6481 and are hardly usable with Emacs. There is a patch for that bug available at least for GnuPG version 2.4.1, which your operating system or distribution might provide already. GnuPG 1.4 is considered a legacy version.
Besides that, all of those branches mentioned above should work flawlessly with Emacs with basic use-cases. They have, however, some incompatible characteristics, which might be visible when used from Emacs.
- The key store format used by GnuPG 2.1 is incompatible with 1.4. That means, a key created with GnuPG 2.1 is not visible with 1.4.
- GnuPG 2.1 uses a fixed address for the Unix domain socket used to
GPG_AGENT_INFOenvironment variable, which is used by GnuPG 2.0 and 1.4, is ignored. That means, if your system has both GnuPG 2.1 and 1.4, the gpg command from GnuPG 1.4 is not able to use
gpg-agentprovided by 2.1 (at least out of box).
- GnuPG 2.1 (2.1.5 or later) has a mechanism to direct the Pinentry password prompt to the Emacs minibuffer. See GnuPG Pinentry.
5 GnuPG Pinentry
An important component of the GnuPG suite is the Pinentry, which
allows for secure entry of passphrases requested by GnuPG. GnuPG
delivers various different programs as Pinentry, ranging from bland
pinentry-tty to fancy graphical dialogs for various
desktop environments, like
pinentry-gnome3. Your operating
system usually determines which of these is used by default.
Note that the selection of a concrete Pinentry program determines only how GnuPG queries for passphrases and not how often. For the latter question see Caching Passphrases.
With some configuration Emacs can also play the role of a Pinentry. The most natural choice, available with GnuPG 2.1.5 and later, is to use Emacs itself as Pinentry for requests that are triggered by Emacs. For example, if you open a file whose name ends with .gpg using automatic decryption, you most likely also want to enter the passphrase for that request in Emacs.
This so called loopback Pinentry has the added benefit that it works also when you use Emacs remotely or from a text-only terminal. To enable it:
Ensure that option
allow-loopback-pinentryis configured for
gpg-agent, which should be the default. See Option Summary in Using the GNU Privacy Guard.
There are other options available to use Emacs as Pinentry, you might
come across a Pinentry called
these are considered insecure or semi-obsolete and might not be
supported by your operating system or distribution. For example,
Debian GNU/Linux supports only the loopback Pinentry described above.
6 Caching Passphrases
Typing passphrases is a troublesome task if you frequently open and close the same file. GnuPG and EasyPG Assistant provide mechanisms to remember your passphrases for a limited time. Using these, you only need to re-enter the passphrase occasionally. However, the configuration is a bit confusing since it depends on your GnuPG installation (see GnuPG Version Compatibility), encryption method (symmetric or public key), and whether or not you want to use GnuPG Agent. As an additional constraint, use of the GnuPG Agent is mandatory for GnuPG 2.0 and later. Here are some questions:
- Do you use GnuPG version 2.0 or later instead of GnuPG version 1.4?
- Do you use symmetric encryption rather than public key encryption?
- Do you want to use GnuPG Agent?
Here are configurations depending on your answers:
|Set up GnuPG Agent.
|Set up GnuPG Agent.
|Set up elisp passphrase cache.
|Set up elisp passphrase cache.
|Set up GnuPG Agent.
|You can’t, without GnuPG Agent.
To set up GnuPG Agent, follow the instruction in Invoking GPG-AGENT in Using the GNU Privacy Guard.
To set up elisp passphrase cache, set
See Encrypting and Decrypting gpg Files.
7 Bug Reports
Bugs and problems with EasyPG Assistant are actively worked on by the Emacs development team. Feature requests and suggestions are also more than welcome. Use M-x report-emacs-bug, see Reporting Bugs in The Emacs Editor.
When submitting a bug report, please try to describe in excruciating detail the steps required to reproduce the problem. Also try to collect necessary information to fix the bug, such as:
- the GnuPG version. Send the output of ‘gpg --version’.
- the GnuPG configuration. Send the contents of ~/.gnupg/gpg.conf.
Before reporting the bug, you should set
epg-debug in the
~/.emacs file and repeat the bug. Then, include the contents
of the *epg-debug* buffer. Note that the first letter of the
buffer name is a whitespace.
Appendix A GNU Free Documentation License
Copyright © 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. https://fsf.org/ Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
The purpose of this License is to make a manual, textbook, or other functional and useful document free in the sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or noncommercially. Secondarily, this License preserves for the author and publisher a way to get credit for their work, while not being considered responsible for modifications made by others.
This License is a kind of “copyleft”, which means that derivative works of the document must themselves be free in the same sense. It complements the GNU General Public License, which is a copyleft license designed for free software.
We have designed this License in order to use it for manuals for free software, because free software needs free documentation: a free program should come with manuals providing the same freedoms that the software does. But this License is not limited to software manuals; it can be used for any textual work, regardless of subject matter or whether it is published as a printed book. We recommend this License principally for works whose purpose is instruction or reference.
- APPLICABILITY AND DEFINITIONS
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- COMBINING DOCUMENTS
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- COLLECTIONS OF DOCUMENTS
You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.
You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.
- AGGREGATION WITH INDEPENDENT WORKS
A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an “aggregate” if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.
If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document’s Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.
Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.
If a section in the Document is Entitled “Acknowledgements”, “Dedications”, or “History”, the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.
You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.
However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.
Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.
Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.
- FUTURE REVISIONS OF THIS LICENSE
The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See https://www.gnu.org/licenses/.
Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License “or any later version” applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Document.
“Massive Multiauthor Collaboration Site” (or “MMC Site”) means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A “Massive Multiauthor Collaboration” (or “MMC”) contained in the site means any set of copyrightable works thus published on the MMC site.
“CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.
“Incorporate” means to publish or republish a Document, in whole or in part, as part of another Document.
An MMC is “eligible for relicensing” if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.
The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.
ADDENDUM: How to use this License for your documents
To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:
Copyright (C) year your name. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled ``GNU Free Documentation License''.
If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with…Texts.” line with this:
with the Invariant Sections being list their titles, with the Front-Cover Texts being list, and with the Back-Cover Texts being list.
If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.
If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.
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