GnuPG - Key Management

Table of Contents
   
Commands
   
Key Generation
Export & Importing Keys
Listing Keys
Editing Keys
Signing Keys
Removing/Revoking Keys
Trust Management
Keyservers
   
Options
   
General
Keys & Keyrings
Algorithms / Hashes
Compatibility
Key Signatures / Certification
Trust Management
Key Signature Notation / Policy URLs
Keyservers
Photo IDs
 
Return to Index
 
GPG is the main program for the GnuPG system.
 
This man page only lists the commands and options available. For more verbose documentation get the GNU Privacy Handbook (GPH) or one of the other documents at http://www.gnupg.org/documentation/ .
 
Please remember that option parsing stops as soon as a non option is encountered, you can explicitly stop option parsing by using the special option "--".
 
 

Commands

 
 
GPG recognizes these commands:  
   
 
 

Key Generation

(Options | Options)    
           
  --gen-key   Example    
         
  Generate a new key pair. This command is normally only used interactively.

There is an experimental feature which allows you to create keys in batch mode. See the file doc/DETAILS in the source distribution on how to use this. 
 
           
 
 

Exporting & Importing Keys

(Options | Options | Options | Options)    
           
  --export names   Example    
         
  Either export all keys from all keyrings (default keyrings and those registered via option --keyring), or if at least one name is given, those of the given name. The new keyring is written to stdout or to the file given with option "output". Use together with --armor to mail those keys.   
           
  --export-all names        
         
  Same as --export, but also exports keys which are not compatible with OpenPGP.  
           
  --export-secret-keys names
--export-secret-subkeys names
Example    
         
  Same as --export, but exports the secret keys instead. This is normally not very useful and a security risk. The second form of the command has the special property to render the secret part of the primary key useless; this is a GNU extension to OpenPGP and other implementations can not be expected to successfully import such a key. See the option --simple-sk-checksum if you want to import such an exported key with an older OpenPGP implementation.   
           
  --import files
--fast-import files
  Example | Example | Example    
         
  Import/merge keys. This adds the given keys to the keyring. The fast version is currently just a synonym. 
 
There are a few other options which control how this command works. Most notable here is the --merge-only option which does not insert new keys but does only the merging of new signatures, user-IDs and subkeys.
 
           
 
 

Listing Keys

(Options | OptionsOptions)    
           
  --list-keys names
--list-public-keys names
  Example     
         
  List all keys from the public keyrings, or just the ones given on the command line. (See also --edit-key)  
           
  --list-secret-keys names   Example    
         
  List all keys from the secret keyrings, or just the ones given on the command line.   
           
  --list-sigs names   Example | Example | Example    
         
  Same as --list-keys, but the signatures are listed too.   
           
  --check-sigs names   Example     
         
  Same as --list-sigs, but the signatures are verified. (See also --edit-key | check)  
           
  --fingerprint names   Example    
         
  List all keys with their fingerprints. This is the same output as --list-keys but with the additional output of a line with the fingerprint. May also be combined with --list-sigs or --check-sigs. If this command is given twice, the fingerprints of all secondary keys are listed too. (See also --edit-key | fpr)  
           
 
 

Editing Keys

(Options)    
           
  --edit-key name    Example    
         
  Present a menu which enables you to do all key related tasks:   
           
 
toggle Toggle between public and secret key listing.  Example
fpr List key with its fingerprint. (See also --fingerprint Example  
check Check all selected user ids. (See also --check-sigs Example  
sign Make a signature on key of user name If the key is not yet signed by the default user (or the users given with -u), the program displays the information of the key again, together with its fingerprint and asks whether it should be signed. This question is repeated for all users specified with -u. (See also --sign-key Example  
lsign Same as --sign but the signature is marked as non-exportable and will therefore never be used by others. This may be used to make keys valid only in the local environment. (See also --lsign-key)
nrsign Same as --sign but the signature is marked as non-revocable and can therefore never be revoked. (See also --nrsign-key)
nrlsign Combines the functionality of nrsign and lsign to make a signature that is both non-revocable and non-exportable.
revsig Revoke a signature. GnuPG asks for every signature which has been done by one of the secret keys, whether a revocation certificate should be generated.  Example
trust Change the owner trust value. This updates the trust-db immediately and no save is required.  Example
adduid Create an alternate user id.  Example
deluid Delete a user id.  Example
primary Flag the current user id as the primary one, removes the primary user id flag from all other user ids and sets the timestamp of all affected self-signatures one second ahead. Note that setting a photo user ID as primary makes it primary over other photo user IDs, and setting a regular user ID as primary makes it primary over other regular user IDs.  Example
uid n Toggle selection of user id with index n. Use 0 to deselect all.
addkey Add a subkey to this key.  Example
delkey Remove a subkey.  Discussion
revkey Revoke a subkey.  Discussion
key n Toggle selection of subkey with index n. Use 0 to deselect all.
expire Change the key expiration time. If a key is selected, the time of this key will be changed. With no selection the key expiration of the primary key is changed.  Discussion
addrevoker Add a designated revoker. This takes one optional argument: "sensitive". If a designated revoker is marked as sensitive, it will not be exported by default (see export-options). (See also --desig-revoke) [Note: new in 1.0.7a]
passwd Change the passphrase of the secret key.  Example
disable / enable Disable or enable an entire key. A disabled key can normally not be used for encryption.
pref List preferences from the selected user ID. This shows the actual pref­erences, without including any implied preferences. Example
showpref More verbose preferences listing for the selected user ID. This shows the preferences in effect by including the implied preferences of 3DES (cipher), SHA-1 (digest), and Uncompressed (compression) if they are not already included in the preference list. Example | Example
setpref string Set the list of user ID preferences to string. This should be a string similar to the one printed by pref.  Using an empty string will set the default preference string, using "none" will set the preferences to nil. Use gpg -v --version to get a list of available algorithms. (See also default-preference-list for a table of acceptable preferences.) This command just initializes an internal list and does not change anything unless another command (such as updpref) which changes the self-signatures is used. (The MDC feature flag is also supported and can be set -- see GnuPG 1.0.7 released.) Example
updpref Change the preferences of all user IDs (or just of the selected ones) to the current list of preferences. The timestamp of all affected self-signatures will be advanced by one second. Note that while you can change the preferences on an attribute user ID (aka "photo ID"), GnuPG does not select keys via attribute user IDs so these preferences will not be used by GnuPG. Example
addphoto Create a photographic user id.
showphoto Display the selected photographic user id.
save Save all changes to the key rings and quit.  Discussion
quit Quit the program without updating the key rings.  Example
 
   
  The listing shows you the key with its secondary keys and all user ids. Selected keys or user ids are indicated by an asterisk. The trust value is displayed with the primary key: the first is the assigned owner trust and the second is the calculated trust value. Letters are used for the values:  
   
 
- No ownertrust assigned / not yet calculated.
e Trust calculation has failed; probably due to an expired key.
q Not enough information for calculation.
n Never trust this key.
m Marginally trusted.
f Fully trusted.
u Ultimately trusted.
 
   
 
 

Signing Keys

(Options | Options | Options | Options)    
           
  --sign-key name   Example | Example    
         
  Signs a public key with your secret key. This is a shortcut version of the subcommand sign from --edit-key  
           
  --lsign-key name        
         
  Signs a public key with your secret key but marks it as non-exportable. This is a shortcut version of the subcommand lsign from --edit-key.  
           
  --nrsign-key name        
         
  Signs a public key with your secret key but marks it as non-revocable. This is a shortcut version of the subcommand nrsign from --edit-key.  
           
 
 

Removing / Revoking Keys

(Options)    
           
  --delete-key name   Example    
         
  Remove key from the public keyring. In batch mode either --yes is required or the key must be specified by fingerprint. This is a safeguard against accidental deletion of multiple keys.  
           
  --delete-secret-key name        
         
  Remove key from the secret and public keyring. In batch mode the key must be specified by fingerprint.  
           
  --delete-secret-and-public-key name   Example    
         
  Same as --delete-key, but if a secret key exists, it will be removed first. In batch mode the key must be specified by fingerprint.  
           
  --gen-revoke   Example    
         
  Generate a revocation certificate for the complete key. To revoke a subkey or a signature, use the  subcommands revkey or revsig from --edit-key.  
           
--desig-revoke        
         
  Generate a designated revocation certificate for a key. This allows a user (with the permission of the keyholder) to revoke someone elses key. (See also --edit-key | addrevoker)  
           
 
 

Trust Management

(Options | Options)    
           
  --update-trustdb        
         
  Do trust DB maintenance. This command goes over all keys and builds the Web-of-Trust. This is an interactive command because it may has to ask for the "ownertrust" values of keys. The user has to give an estimation in how far she trusts the owner of the displayed key to correctly certify (sign) other keys. It does only ask for that value if it has not yet been assigned to a key. Using the edit menu, that value can be changed at any time later.  
           
  --check-trustdb        
         
  Do trust DB maintenance without user interaction. Form time to time the trust database must be updated so that expired keys and resulting changes in the Web-of-Trust can be tracked. GnuPG tries to figure when this is required and then does it implicitly; this command can be used to force such a check. The processing is identically to that of --update-trustdb but it skips keys with a not yet defined "ownertrust".

For use with cron jobs, this command can be used together with --batch in which case the check is only done when it is due. To force a run even in batch mode add the option --yes.
 
           
  --export-ownertrust file        
         
  Store the ownertrust values into file (or stdin if not given). This is useful for backup purposes as these values are the only ones which can't be re-created from a corrupted trust DB.  
           
  --import-ownertrust files        
         
  Update the trustdb with the ownertrust values stored in files (or stdin if not given); existing values will be overwritten.   
           
 
 

Keyservers

(Options | Options | Options)    
           
  --send-keys names        
         
  Same as --export but sends the keys to a keyserver. Option --keyserver must be used to give the name of this keyserver. Don't send your complete keyring to a keyserver. Select only those keys which are new or changed by you.  
           
  --recv-keys key_IDs        
         
  Import the keys with the given key_IDs from a keyserver. Option --keyserver must be used to give the name of this keyserver.  
           
  --search-keys names        
         
  Search the keyserver for the given names. Multiple names given here will be joined together to create the search string for the keyserver. Option --keyserver must be used to give the name of this keyserver.   
           
 

Options

 
 
Starting with GnuPG 1.1.92 (incl. GnuPG 1.2.1, 1.2.0 and 1.1.92), long options can be put in an options file (default "~/.gnupg/gpg.conf"). In GnuPG versions up through GnuPG 1.1.91 (incl. 1.0.6, 1.0.7, and 1.1.91), long options can be put in an "old style" configuration file (default "~/.gnupg/options"). 

Short option names will not work -- for example, armor is a valid option for the options file, while a is not. Do not write the 2 dashes, but simply the name of the option and any required arguments. Lines with a hash as the first non-white-space character are ignored. Commands may be put in this file too, but that does not make sense.

GPG recognizes these options: 

 
   
 
 

General

       
           
  -a, --armor        
         
  Create ASCII armored output.  
           
  -o, --output file        
         
  Write output to file.  
           
  -u, --local-user name        
         
  Use name as the user ID to sign. This option is silently ignored for the list commands, so that it can be used in an options file.  
           
 
 
Keys & Keyrings        
           
  --show-keyring        
         
  Causes --list-keys, --list-public-keys, and --list-secret-keys to display the name of the keyring a given key resides on. This is only useful when you're listing a specific key or set of keys. It has no effect when listing all keys.  
           
  --keyring file        
         
  Add file to the list of keyrings. If file begins with a tilde and a slash, these are replaced by the HOME directory. If the filename does not contain a slash, it is assumed to be in the home-directory ("~/.gnupg" if --homedir is not used). The filename may be prefixed with a scheme:

"gnupg-ring:" is the default one.

It might make sense to use it together with --no-default-keyring.
 
           
  --secret-keyring file        
         
  Same as --keyring but for the secret keyrings.   
           
  --no-default-keyring        
         
  Do not add the default keyrings to the list of keyrings.  
           
  --merge-only        
         
  Don't insert new keys into the keyrings while doing an import.  
           
  --allow-secret-key-import   Discussion    
         
  This is an obsolete option and is not used anywhere.   
           
  --import-options parameters        
         
  This is a space or comma delimited string that gives options for importing keys. Options can be prepended with a "no-" to give the opposite meaning. The options are:  
           
  
  allow-local-sigs Allow importing key signatures marked as "local". This is not generally useful unless a shared keyring scheme is being used. Defaults to no.  
  repair-hkp-subkey-bug During import, attempt to repair the HKP keyserver mangling multiple subkeys bug. Note that this cannot completely repair the damaged key as some crucial data is removed by the keyserver, but it does at least give you back one subkey. Defaults to no for regular --import and to yes for keyserver --recv-keys.   
 
           
  --export-options parameters        
         
  This is a space or comma delimited string that gives options for exporting keys. Options can be prepended with a "no-" to give the opposite meaning. The options are:  
           
  
  include-non-rfc Include non-RFC compliant keys in the export. Defaults to yes.  
  include-local-sigs Allow exporting key signatures marked as "local." This is not generally useful unless a shared keyring scheme is being used. Defaults to no.   
  include-attributes Include attribute user IDs (photo IDs) while exporting. This is useful to export keys if they are going to be used by an OpenPGP program that does not accept attribute user IDs. Defaults to yes.  
  include-sensitive-revkeys Include designated revoker information that was marked as "sensitive." Defaults to no.   
 
           
  --preserve-permissions        
         
  Don't change the permissions of a secret keyring back to user read/write only. Use this option only if you really know what you are doing.  
           
  --with-colons        
         
  Print key listings delimited by colons. Note, that the output will be encoded in UTF-8 regardless of any --charset setting.  
           
  --with-key-data        
         
  Print key listings delimited by colons (like --with-colons) and print the public key data.  
           
  --with-fingerprint        
         
  Same as the command --fingerprint but changes only the format of the output and may be used together with another command.  
           
  --fast-list-mode        
         
  Changes the output of the list commands to work faster; this is achieved by leaving some parts empty. Some applications don't need the user ID and the trust information given in the listings. By using this option, they can get a faster listing. The exact behaviour of this option may change in future versions.  
           
  --fixed-list-mode        
         
  Do not merge user ID and primary key in --with-colons listing mode and print all timestamps as seconds since 1970-01-01.  
           
  --list-only        
         
  Changes the behaviour of some commands. This is like --dry-run but different in some cases. The semantic of this command may be extended in the future. Currently it only skips the actual decryption pass and therefore enables a fast listing of the encryption keys.  
           
  --sk-comments        
         
  Include secret key comment packets when exporting secret keys. This is a GnuPG extension to the OpenPGP standard, and is off by default. Please note that this has nothing to do with the comments in clear text signatures or armor headers.  
           
  --no-sk-comments        
         
  Resets the --sk-comments option.  
           
  --no-comment        
         
  See --sk-comments. This option is deprecated and may be removed soon.  
           
 
 

Algorithms / Hashes

       
           
  --cipher-algo name        
         
  Use name as cipher algorithm. Running the program with the command --version yields a list of supported algorithms. If this is not used the cipher algorithm is selected from the preferences stored with the key. (Default cipher-algo is CAST5 -- see GnuPG 1.0.7 released.)  
           
  --disable-cipher-algo name        
         
  Never allow the use of name as cipher algorithm. The given name will not be checked so that a later loaded algorithm will still get disabled.  
           
  --disable-pubkey-algo name        
         
  Never allow the use of name as public key algorithm. The given name will not be checked so that a later loaded algorithm will still get disabled.   
           
  --digest-algo name        
         
  Use name as message digest algorithm. Running the program with the command --version yields a list of supported algorithms. (Default digest-algo is SHA1 -- see GnuPG 1.0.7 released.)  
           
  --cert-digest-algo name        
         
  Use name as the message digest algorithm used when signing a key. Running the program with the command --version yields a list of supported algorithms. Be aware that if you choose an algorithm that GnuPG supports but other OpenPGP implementations do not, then some users will not be able to use the key signatures you make, or quite possibly your entire key. (Default is MD5 for PGP2 keys and SHA1 for all othr keys -- see GnuPG 1.1.90 released.)  
           
  --compress-algo n        
         
  Use compression algorithm n. Default is 2 which is RFC 1950 (ZLIB) compression. You may use 1 to use the old zlib version (RFC 1951, DEFLATE, ZIP) which is used by PGP. 0 disables compression. The default algorithm may give better results because the window size is not limited to 8K. If this is not used the OpenPGP behavior is used, i.e. the compression algorithm is selected from the preferences; note, that this can't be done if you do not encrypt the data.  
           
  --personal-cipher-preferences string Discussion    
         
  Set the list of personal cipher preferences to string. This list should be a string similar to the one printed by the command pref in the edit-key menu. This allows the user to factor in their own preferred algorithms when algorithms are chosen via recipient key preferences.  
           
  --personal-digest-preferences string Discussion    
         
  Set the list of personal digest preferences to string. This list should be a string similar to the one printed by the command pref in the edit-key menu. This allows the user to factor in their own preferred algorithms when algorithms are chosen via recipient key preferences.  
           
  --personal-compress-preferences string Discussion    
         
  Set the list of personal compression preferences to string. This list should be a string similar to the one printed by the command pref in the edit-key menu. This allows the user to factor in their own preferred algorithms when algorithms are chosen via recipient key preferences.  
           
  --default-preference-list string Discussion    
         
  Set the list of default preferences to string. This list should be a string similar to the one printed by the command pref in the edit-key menu. This affects both key generation and updpref in the edit-key menu. (See also edit-key | setpref  
           
 

Symmetric Encryption Algorithms

Pref Code (n) Algorithm (name)
s1 * IDEA
s2 3DES
s3 CAST5
s4 Blowfish
s7 AES (128)
s8 AES192
s9 AES256
s10 Twofish

* only with IDEA module

Digest (Hash) Algorithms

Pref Code (n) Algorithm (name)
h1 MD5
h2 SHA1
h3 RIPEMD160
h6 + TIGER192
h8 * SHA256
h9 * SHA384
h10 * SHA512

* only with SHA-2 module & SHA-2 patch
+ only with TIGER module

Compression Algorithms

Pref Code (n) Algorithm (name)
z0 uncompressed
z1 ZIP (RFC 1951)
z2 ZLIB (RFC 1950)

The default preferences for GPG keys are:

Algorithm Type Preferences (in order)
Symmetric cipher AES (128), CAST5, 3DES, IDEA
Hash SHA1, RIPEMD160
Compression ZLIB, ZIP
 
  For more information on these algorithms, see Werner Koch's commented, HTML version of RFC2440: RFC2440 & GnuPG.  
           
  --s2k-cipher-algo name        
         
  Use name as the cipher algorithm used to protect secret keys. The default cipher is CAST5. This cipher is also used for conventional encryption if --cipher-algo is not given.  
           
  --s2k-digest-algo name        
         
  Use name as the digest algorithm used to mangle the passphrases. The default algorithm is RIPE-MD-160. This digest algorithm is also used for conventional encryption if --digest-algo is not given.  
           
  --s2k-mode n        
         
  Selects how passphrases are mangled. If n is 0 a plain passphrase (which is not recommended) will be used, a 1 (default) adds a salt to the passphrase and a 3 iterates the whole process a couple of times. Unless --rfc1991 is used, this mode is also used for conventional encryption.  
           
  --simple-sk-checksum    Example    
         
  Secret keys are integrity protected by using a SHA-1 checksum. This method will be part of an enhanced OpenPGP specification but GnuPG already uses it as a countermeasure against certain attacks. Old applications don't understand this new format, so this option may be used to switch back to the old behaviour. Using this this option bears a security risk. Note that using this option only takes effect when the secret key is encrypted -- the simplest way to make this happen is to change the passphrase on the key (even changing it to the same value is acceptable). (See --edit-key | passwd)  
           
 
 

Compatibility

       
           
  --rfc1991        
         
  Try to be more RFC1991 (PGP 2.x) compliant.  
           
--pgp2   Example    
         
  Set up all options to be as PGP 2.x compliant as possible, and warn if an action is taken (e.g. encrypting to a non-RSA key) that will create a message that PGP 2.x will not be able to handle. Note that `PGP 2.x' here means `MIT PGP 2.6.2'. There are other versions of PGP 2.x available, but the MIT release is a good common baseline.

This option implies "--rfc1991 -no-openpgp -disable-mdc --no-force-v4-certs -no-comment -escape-from-lines -force-v3-sigs --no-ask-sig-expire -no-ask-cert-expire -cipher-algo IDEA --digest-algo MD5 -compress-algo 1."
[Note: new in 1.0.7]
 
           
  --no-pgp2        
         
  Resets the --pgp2 option.  
           
  --pgp6        
         
  Set up all options to be as PGP 6 compliant as possible. This restricts you to the ciphers IDEA (if the IDEA plugin is installed), 3DES, and CAST5, the hashes MD5, SHA1 and RIPEMD160, and the compression algorithms none and ZIP. This also disables making signatures with signing subkeys as PGP 6 does not understand signatures made by signing subkeys.

This option implies "--disable-mdc -no-comment -escape-from-lines --force-v3-sigs -no-ask-sig-expire -compress-algo 1." [Note: new in 1.0.7]
 
           
  --no-pgp6        
         
  Resets the --pgp6 option.  
           
  --pgp7        
         
  Set up all options to be as PGP 7 compliant as possible. This is identical to --pgp6 except that MDCs are not disabled, and the list of allowable ciphers is expanded to add AES128, AES192, AES256, and TWOFISH. [Note: new in 1.0.7a]  
           
  --no-pgp7        
         
  Resets the --pgp7 option.  
           
  --openpgp        
         
  Reset all packet, cipher and digest options to OpenPGP behavior. Use this option to reset all previous options like --rfc1991, --force-v3-sigs, --s2k-*, --cipher-algo, --digest-algo and --compress-algo to OpenPGP compliant values. All PGP workarounds are also disabled.  
           
  --force-v3-sigs        
         
  OpenPGP states that an implementation should generate v4 signatures but PGP versions 5 and higher only recognize v4 signatures on key material. This option forces v3 signatures for signatures on data. Note that this option overrides --ask-sig-expire, as v3 signatures cannot have expiration dates.  
           
  --no-force-v3-sigs        
         
  Reset the --force-v3-sigs option.  
           
  --force-v4-certs        
         
  Always use v4 key signatures even on v3 keys. This option also changes the default hash algorithm for v3 RSA keys from MD5 to SHA-1.  
           
  --no-force-v4-certs        
         
  Reset the --force-v4-certs option.  
           
  --force-mdc        
         
  Force the use of encryption with appended manipulation code. This is always used with the newer ciphers (those with a blocksize greater than 64 bit).  
           
  --no-mdc-warning        
         
  Suppress the warning about missing MDC integrity protection.  
           
  --allow-non-selfsigned-uid   Discussion    
         
  Allow the import and use of keys with user IDs which are not self-signed. This is not recommended, as a nonself-signed user ID is trivial to forge.   
           
  --no-allow-non-selfsigned-uid      
         
  Reset the --allow-non-selfsigned-uid option.  
           
  --allow-freeform-uid        
         
  Disable all checks on the form of the user ID while generating a new one. This option should only be used in very special environments as it does not ensure the de-facto standard format of user IDs.  
           
  --ignore-time-conflict        
         
  GnuPG normally checks that the timestamps associated with keys and signatures have plausible values. However, sometimes a signature seems to be older than the key due to clock problems. This option makes these checks just a warning.  
           
  --ignore-valid-from        
         
  GnuPG normally does not select and use subkeys created in the future. This option allows the use of such keys and thus exhibits the pre-1.0.7 behaviour. You should not use this option unless you there is some clock problem.  
           
  --ignore-crc-error        
         
  The ASCII armor used by OpenPG is protected by a CRC checksum against transmission errors. Sometimes it happens that the CRC gets mangled somewhere on the transmission channel but the actual content (which is anyway protected by the OpenPGP protocol) is still okay. This option will let gpg ignore CRC errors.  
           
  --expert   Example | Example    
         
  Allow the user to do certain nonsensical or "silly" things like signing an expired or revoked key, or certain potentially incompatible things like generating deprecated key types. This also disables certain warning messages about potentially incompatible actions. (In expert mode, the user can re-sign a v3 key with a v4 self-signature. This does not change the v3 key into a v4 key, but it does allow the user to use preferences, primary ID flags, etc. -- see GnuPG 1.1.90 released.) As the name implies, this option is for experts only. If you don't fully understand the implications of what it allows you to do, leave this off. [Note: new in 1.0.7]  
           
  --no-expert        
         
  Resets the --expert option.   
           
 
 

Key Signatures / Certification

       
           
   --completes-needed n        
         
  Number of completely trusted users to introduce a new key signer (defaults to 1).  
           
  --marginals-needed n        
         
  Number of marginally trusted users to introduce a new key signer (defaults to 3).  
           
  --max-cert-depth n        
         
  Maximum depth of a certification chain (default is 5).   
           
  --no-sig-cache        
         
  Do not cache the verification status of key sig­ natures. Caching gives a much better performance in key listings. However, if you suspect that your public keyring is not save against write modifications, you can use this option to disable the caching. It probably does not make sense to disable it because all kind of damage can be done if someone else has write access to your public keyring.  
           
  --no-sig-create-check        
         
  GnuPG normally verifies each signature right after creation to protect against bugs and hardware malfunctions which could leak out bits from the secret key. This extra verification needs some time (about 115% for DSA keys), and so this option can be used to disable it. However, due to the fact that the signature creation needs manual interaction, this performance penalty does not matter in most settings.   
           
  --ask-cert-expire        
         
  When making a key signature, prompt for an expiration time. If this option is not specified, the expiration time is "never."  
           
  --no-ask-cert-expire        
         
  Resets the --ask-cert-expire option.   
           
 
 

Trust Management

       
           
  --default-cert-check-level n        
         
  The default to use for the check level when signing a key.  
           
  
0 means you make no particular claim as to how carefully you verified the key.
1 means you believe the key is owned by the person who claims to own it but you could not, or did not verify the key at all. This is useful for a "persona" verification, where you sign the key of a pseudonymous user.
2 means you did casual verification of the key. For example, this could mean that you verified that the key fingerprint and checked the user ID on the key against a photo ID.
3 means you did extensive verification of the key. For example, this could mean that you verified the key fingerprint with the owner of the key in person, and that you checked, by means of a hard to forge document with a photo ID (such as a passport) that the name of the key owner matches the name in the user ID on the key, and finally that you verified (by exchange of email) that the email address on the key belongs to the key owner.
 
           
  Note that the examples given above for levels 2 and 3 are just that: examples. In the end, it is up to you to decide just what "casual" and "extensive" mean to you.

This option defaults to 0.
 
           
  --trusted-key long_key_ID        
         
  Assume that the specified key (which must be given as a full 8 byte key ID) is as trustworthy as one of your own secret keys. This option is useful if you don't want to keep your secret keys (or one of them) online but still want to be able to check the validity of a given recipient's or signator's key.  
           
  --always-trust        
         
  Skip key validation and assume that used keys are always fully trusted. You won't use this unless you have installed some external validation scheme. This option also suppresses the "[uncertain]" tag printed with signature checks when there is no evidence that the user ID is bound to the key.   
           
  --auto-check-trustdb        
         
  If GnuPG feels that its information about the Web-of-Trust has to be updated, it automatically runs the --check-trustdb command internally. This may be a time consuming process.  
           
  --no-auto-check-trustdb        
         
  Resets the --auto-check-trustdb option.   
           
  --no-expensive-trust-checks        
         
  Experimental use only.  
           
 
 

Key Signature Notation / Policy URLs

   
           
  --show-notation        
         
  Show key signature notations in the --list-sigs or --check-sigs listings.  
           
  --no-show-notation        
         
  Do not show key signature notations in the --list-sigs or --check-sigs listings.  
           
  --set-policy-url string        
         
  Use string as Policy URL for signatures (RFC2440: 5.2.3.19). If you prefix it with an exclamation mark, the policy URL packet will be flagged as critical.  
           
  --show-policy-url        
         
  Show any policy URLs set in the --list-sigs or --check-sigs listings.  
           
  --no-show-policy-url        
         
  Do not show any policy URLs set in the --list-sigs or --check-sigs listings.   
           
 
 

Keyservers

       
           
  --keyserver name        
         
  Use name as your keyserver. This is the server that --recv-keys, --send-keys, and --search-keys will communicate with to receive keys from, send keys to, and search for keys on. The format of the name is a URL: "scheme:[//]keyservername[:port]" The scheme is the type of keyserver: "hkp" for the Horowitz (or compatible) keyservers, "ldap" for the NAI LDAP keyserver, or "mailto" for the Horowitz email keyserver. Note that your particular installation of GnuPG may have other keyserver types available as well.

Most keyservers synchronize with each other, so there is generally no need to send keys to more than one server. Using the command "host -l pgp.net | grep wwwkeys" gives you a list of HKP keyservers. When using one of the wwwkeys servers, due to load balancing using round-robin DNS you may notice that you get a different key server each time.
 
           
  --keyserver-options parameters      
         
  This is a space or comma delimited string that gives options for the keyserver. Options can be prepended with a "no-" to give the opposite meaning. Valid import-options or export-options may be used here as well to apply to importing (--recv-keys) or exporting (--send-keys) a key from or to a keyserver. While not all options are available for all keyserver types, some common options are:   
           
  
include-revoked When receiving or searching for a key, include keys that are marked on the keyserver as revoked. Note that this option is always set when using the NAI HKP keyserver, as this keyserver does not differentiate between revoked and unrevoked keys.
include-disabled When receiving or searching for a key, include keys that are marked on the keyserver as disabled. Note that this option is not used with HKP keyservers, as they do not support disabling keys.
use-temp-files On most Unix-like platforms, GnuPG communicates with the keyserver helper program via pipes, which is the most efficient method. This option forces GnuPG to use temporary files to communicate. On some platforms (such as Win32 and RISC OS), this option is always enabled.
keep-temp-files If using use-temp-files, do not delete the temp files after using them. This option is useful to learn the keyserver communication protocol by reading the temporary files.
verbose Tell the keyserver helper program to be more verbose. This option can be repeated multiple times to increase the verbosity level.
honor-http-proxy For keyserver schemes that use HTTP (such as HKP), try to access the keyserver over the proxy set with the environment variable "http_proxy".
auto-key-retrieve This option enables the automatic retrieving of keys from a keyserver when verifying signatures made by keys that are not on the local keyring. 
 
           
 
 

Photo IDs

       
           
  --show-photos        
         
  Causes --list-keys, --list-sigs, --list-public-keys, --list-secret-keys, and verifying a signature to also display the photo ID attached to a key, if any. See also --photo-viewer. [Note: new in 1.0.7]  
           
  --no-show-photos        
         
  Resets the --show-photos flag.  
           
  --photo-viewer string        
         
  This is the command line that should be run to view a photo ID. "%i" will be expanded to a filename containing the photo. "%I" does the same, except the file will not be deleted once the viewer exits. Other flags are "%k" for the key ID, "%K" for the long key ID, "%f" for the key fingerprint, "%t" for the extension of the image type (e.g. "jpg"), "%T" for the MIME type of the image (e.g. "image/jpeg"), and "%%" for an actual percent sign. If neither %i or %I are present, then the photo will be supplied to the viewer on standard input.

The default viewer is "xloadimage -fork -quiet -title 'KeyID 0x%k' stdin" 
 
           

Home [frames]        Home [no frames]

© 2000, 2001, 2002 Eric L. Howes (eburger68@myrealbox.com)