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See ChangeLog: Thu Sep 14 14:20:38 CEST 2000 Werner Koch

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Werner Koch 2000-09-14 12:20:30 +00:00
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7
ChangeLog
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@ -1,3 +1,10 @@
Thu Sep 14 14:20:38 CEST 2000 Werner Koch <wk@openit.de>
* acinclude.m4 (GNUPG_CHECK_FAQPROG): New.
* configure.in: Test for this.
* configure.in (DYNLINK_MOD_CFLAGS): Fix by David Champion.
Wed Sep 6 17:55:47 CEST 2000 Werner Koch <wk@openit.de> Wed Sep 6 17:55:47 CEST 2000 Werner Koch <wk@openit.de>
* configure.in: Check for fstat64 and fopen64 * configure.in: Check for fstat64 and fopen64

5
NEWS
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@ -20,6 +20,11 @@ Noteworthy changes in the current CVS branch STABLE-BRANCH-1-0
* RSA is supported. Key generation does not yet work but will come * RSA is supported. Key generation does not yet work but will come
soon. soon.
* CAST5 and SHA-1 are now the default algorithms to protect the key
and for symmetric-only encryption. This should solve a couple
of compatibility problems because the old algorithms are optional
according to RFC2440
Noteworthy changes in version 1.0.2 (2000-07-12) Noteworthy changes in version 1.0.2 (2000-07-12)
---------------------------------------------- ----------------------------------------------

4
THANKS
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@ -26,11 +26,12 @@ Christian Recktenwald chris@citecs.de
Daniel Eisenbud eisenbud@cs.swarthmore.edu Daniel Eisenbud eisenbud@cs.swarthmore.edu
Daniel Koening dan@mail.isis.de Daniel Koening dan@mail.isis.de
Daniel Resare daniel@resare.com Daniel Resare daniel@resare.com
Detlef Lannert lannert@lannert.rz.uni-duesseldorf.de
Dave Dykstra dwd@bell-labs.com Dave Dykstra dwd@bell-labs.com
David Champion dgc@uchicago.edu
David Ellement ellement@sdd.hp.com David Ellement ellement@sdd.hp.com
David Hallinan hallinan@rtd.com David Hallinan hallinan@rtd.com
David Mathog MATHOG@seqaxp.bio.caltech.edu David Mathog MATHOG@seqaxp.bio.caltech.edu
Detlef Lannert lannert@lannert.rz.uni-duesseldorf.de
Dimitri dmitri@advantrix.com Dimitri dmitri@advantrix.com
Dirk Lattermann dlatt@t-online.de Dirk Lattermann dlatt@t-online.de
Ed Boraas ecxjo@esperanto.org Ed Boraas ecxjo@esperanto.org
@ -67,6 +68,7 @@ Jeff Long long@kestrel.cc.ukans.edu
Jens Bachem bachem@rrz.uni-koeln.de Jens Bachem bachem@rrz.uni-koeln.de
Jeroen C. van Gelderen jeroen@vangelderen.org Jeroen C. van Gelderen jeroen@vangelderen.org
J Horacio MG homega@ciberia.es J Horacio MG homega@ciberia.es
J. Michael Ashley jashley@acm.org
Joachim Backes backes@rhrk.uni-kl.de Joachim Backes backes@rhrk.uni-kl.de
John A. Martin jam@jamux.com John A. Martin jam@jamux.com
Johnny Teveßen j.tevessen@gmx.de Johnny Teveßen j.tevessen@gmx.de

8
TODO
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@ -1,10 +1,11 @@
* Think more whether the setting to ultimately trusted is a good idea.!! * add a way to set expiration time for key signatures.
* add some minor things vor VMS. * add some minor things vor VMS.
* Don't get the ultimately trusted keys from the secring but store * Don't get the ultimately trusted keys from the secring but store
it permanently in the trustdb. This way we don't need a secring at all. it permanently in the trustdb. This way we don't need a secring at all.
[ Solved by re-introducing --trusted-key ]
* Use DSA keys with the test suite. * Use DSA keys with the test suite.
@ -21,6 +22,8 @@
* Replace Valid/Invalid by Known/Unknown? * Replace Valid/Invalid by Known/Unknown?
* Fix the bug in the mips assembler code
Scheduled for 1.1 Scheduled for 1.1
----------------- -----------------
* export by user-IDs does only export the first matching name which leads * export by user-IDs does only export the first matching name which leads
@ -42,6 +45,7 @@ Scheduled for 1.1
* Skip RO keyrings when importing a key. * Skip RO keyrings when importing a key.
* Use the newest encryption key if only the main key has been given. * Use the newest encryption key if only the main key has been given.
[already in the gpg 1.1 codebase]
* replace the keyserver stuff either by a call to a specialized * replace the keyserver stuff either by a call to a specialized
utility and SOCKSify this utility. utility and SOCKSify this utility.
@ -52,6 +56,8 @@ Scheduled for 1.1
* Delay the read of the passphrase-fd after a NEED_PASSPHRASE. But this * Delay the read of the passphrase-fd after a NEED_PASSPHRASE. But this
may break some scripts. may break some scripts.
* Get new assembler stuff from gmgp 3.1
Nice to have Nice to have
------------ ------------

2
VERSION
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@ -1,3 +1 @@
1.0.2c 1.0.2c

26
acinclude.m4
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@ -45,6 +45,32 @@ AC_DEFUN(GNUPG_CHECK_GNUMAKE,
]) ])
dnl GNUPG_CHECK_FAQPROG
dnl
AC_DEFUN(GNUPG_CHECK_FAQPROG,
[ AC_MSG_CHECKING(for faqprog.pl)
if faqprog.pl -V 2>/dev/null | grep '^faqprog.pl ' >/dev/null 2>&1; then
working_faqprog=yes
FAQPROG="faqprog.pl"
else
working_faqprog=no
FAQPROG=": "
fi
AC_MSG_RESULT($working_faqprog)
AC_SUBST(FAQPROG)
AM_CONDITIONAL(WORKING_FAQPROG, test "$working_faqprog" = "yes" )
if test $working_faqprog = no; then
AC_MSG_WARN([[
***
*** It seems that the faqprog.pl program is not installed.
*** Unless you do not change the source of the FAQs it is not required.
*** The working version of this utility should be available at:
*** ftp://ftp.gnupg.org/pub/gcrypt/contrib/faqprog.pl
***]])
fi
])
dnl GNUPG_LINK_FILES( SRC, DEST ) dnl GNUPG_LINK_FILES( SRC, DEST )
dnl same as AC_LINK_FILES, but collect the files to link in dnl same as AC_LINK_FILES, but collect the files to link in

5
cipher/ChangeLog
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@ -1,3 +1,8 @@
Thu Sep 14 14:20:38 CEST 2000 Werner Koch <wk@openit.de>
* random.c (fast_random_poll): Check ENOSYS for getrusage.
* rndunix.c: Add 2 sources for QNX. By Sam Roberts.
Wed Sep 13 18:12:34 CEST 2000 Werner Koch <wk@openit.de> Wed Sep 13 18:12:34 CEST 2000 Werner Koch <wk@openit.de>
* rsa.c (secret): Speed up by using the CRT. For a 2k keys this * rsa.c (secret): Speed up by using the CRT. For a 2k keys this

5
cipher/random.c
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@ -594,8 +594,11 @@ fast_random_poll()
#endif #endif
#else #else
{ struct rusage buf; { struct rusage buf;
if( getrusage( RUSAGE_SELF, &buf ) ) /* QNX/Neutrino does return ENOSYS - so we just ignore it and
* add whatever is in buf */
if( getrusage( RUSAGE_SELF, &buf ) && errno != ENOSYS )
BUG(); BUG();
add_randomness( &buf, sizeof buf, 1 ); add_randomness( &buf, sizeof buf, 1 );
memset( &buf, 0, sizeof buf ); memset( &buf, 0, sizeof buf );
} }

5
cipher/rndunix.c
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@ -242,6 +242,7 @@ static struct RI {
{ "/usr/ucb/ps", "aux", SC(0.3), NULL, 0, 0, 0, 1 }, { "/usr/ucb/ps", "aux", SC(0.3), NULL, 0, 0, 0, 1 },
{ "/usr/bin/ps", "aux", SC(0.3), NULL, 0, 0, 0, 1 }, { "/usr/bin/ps", "aux", SC(0.3), NULL, 0, 0, 0, 1 },
{ "/bin/ps", "aux", SC(0.3), NULL, 0, 0, 0, 0 }, { "/bin/ps", "aux", SC(0.3), NULL, 0, 0, 0, 0 },
{ "/bin/ps", "-A", SC(0.3), NULL, 0, 0, 0, 0 }, /*QNX*/
{ "/usr/bin/ipcs", "-a", SC(0.5), NULL, 0, 0, 0, 1 }, { "/usr/bin/ipcs", "-a", SC(0.5), NULL, 0, 0, 0, 1 },
{ "/bin/ipcs", "-a", SC(0.5), NULL, 0, 0, 0, 0 }, { "/bin/ipcs", "-a", SC(0.5), NULL, 0, 0, 0, 0 },
/* Unreliable source, depends on system usage */ /* Unreliable source, depends on system usage */
@ -290,6 +291,10 @@ static struct RI {
/* This is a complex and screwball program. Some systems have things /* This is a complex and screwball program. Some systems have things
* like rX_dmn, x = integer, for RAID systems, but the statistics are * like rX_dmn, x = integer, for RAID systems, but the statistics are
* pretty dodgy */ * pretty dodgy */
#ifdef __QNXNTO__
{ "/bin/pidin", "-F%A%B%c%d%E%I%J%K%m%M%n%N%p%P%S%s%T", SC(0.3),
NULL, 0, 0, 0, 0 },
#endif
#if 0 #if 0
/* The following aren't enabled since they're somewhat slow and not very /* The following aren't enabled since they're somewhat slow and not very
* unpredictable, however they give an indication of the sort of sources * unpredictable, however they give an indication of the sort of sources

11
configure.in
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@ -159,7 +159,7 @@ AC_PROG_INSTALL
AC_PROG_AWK AC_PROG_AWK
AC_CHECK_PROG(DOCBOOK_TO_MAN, docbook-to-man, yes, no) AC_CHECK_PROG(DOCBOOK_TO_MAN, docbook-to-man, yes, no)
AM_CONDITIONAL(HAVE_DOCBOOK_TO_MAN, test "$ac_cv_prog_DOCBOOK_TO_MAN" = yes) AM_CONDITIONAL(HAVE_DOCBOOK_TO_MAN, test "$ac_cv_prog_DOCBOOK_TO_MAN" = yes)
GNUPG_CHECK_FAQPROG
MPI_OPT_FLAGS="" MPI_OPT_FLAGS=""
@ -257,13 +257,13 @@ case "${target}" in
*-openbsd*) *-openbsd*)
NAME_OF_DEV_RANDOM="/dev/srandom" NAME_OF_DEV_RANDOM="/dev/srandom"
NAME_OF_DEV_URANDOM="/dev/urandom" NAME_OF_DEV_URANDOM="/dev/urandom"
DYNLINK_MOD_CFLAGS="-shared -rdynamic -fpic -Wl,-Bshareable -Wl,-x" DYNLINK_MOD_CFLAGS="-shared -rdynamic $CFLAGS_PIC -Wl,-Bshareable -Wl,-x"
;; ;;
*-netbsd*) *-netbsd*)
NAME_OF_DEV_RANDOM="/dev/random" NAME_OF_DEV_RANDOM="/dev/random"
NAME_OF_DEV_URANDOM="/dev/urandom" NAME_OF_DEV_URANDOM="/dev/urandom"
DYNLINK_MOD_CFLAGS="-shared -rdynamic -fpic -Wl,-Bshareable -Wl,-x" DYNLINK_MOD_CFLAGS="-shared -rdynamic $CFLAGS_PIC -Wl,-Bshareable -Wl,-x"
;; ;;
*-solaris*) *-solaris*)
@ -275,7 +275,12 @@ case "${target}" in
*) *)
NAME_OF_DEV_RANDOM="/dev/random" NAME_OF_DEV_RANDOM="/dev/random"
NAME_OF_DEV_URANDOM="/dev/urandom" NAME_OF_DEV_URANDOM="/dev/urandom"
# -shared is a gcc-ism. Find pic flags from GNUPG_CHECK_PIC.
if test -n "$GCC" ; then
DYNLINK_MOD_CFLAGS="-shared $CFLAGS_PIC" DYNLINK_MOD_CFLAGS="-shared $CFLAGS_PIC"
else
DYNLINK_MOD_CFLAGS="$CFLAGS_PIC"
fi
;; ;;
esac esac
AC_DEFINE_UNQUOTED(NAME_OF_DEV_RANDOM, "$NAME_OF_DEV_RANDOM") AC_DEFINE_UNQUOTED(NAME_OF_DEV_RANDOM, "$NAME_OF_DEV_RANDOM")

5
doc/ChangeLog
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@ -1,3 +1,8 @@
Thu Sep 14 14:20:38 CEST 2000 Werner Koch <wk@openit.de>
* faq.raw: New.
* Makefile.am: Support to build FAQs
Wed Jul 12 13:32:06 CEST 2000 Werner Koch <wk@> Wed Jul 12 13:32:06 CEST 2000 Werner Koch <wk@>
* gpg.sgml: Add a note about the availability of the GPH. * gpg.sgml: Add a note about the availability of the GPH.

925
doc/FAQ
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@ -1,240 +1,245 @@
GNU Privacy Guard -- Frequently Asked Questions
=================================================
This FAQ is partly compiled from messages of the developers mailing list.
Many thanks to Kirk Fort, Brian Warner, ...
Q: How does this whole thing work? GNUPG FREQUENTLY ASKED QUESTIONS
A: To generate a secret/public keypair, run
gpg --gen-key Version: 0.1
Last-Modified: Sep 14, 2000
Maintained-by: Nils Ellmenreich <nils 'at' infosun.fmi.uni-passau.de>
and choose the default values. This is the GnuPG FAQ. The latest HTML version is available
here. <http://www.gnupg.org>
Data that is encrypted with a public key can only be decrypted by the The index is generated automatically, so there may be errors here. Not
matching secret key. The secret key is protected by a password, the all questions may be in the section they belong to. Suggestions about
public key is not. how to improve the structure of this FAQ are welcome.
So to send your friend a message, you would encrypt your message with his Please send additions and corrections to the maintainer. Don't send
public key, and he would only be able to decrypt it by having the secret message like "This should be a FAQ - what's the answer?". If it hasn't
key and putting in the password to use his secret key. been asked before, it isn't a FAQ. Otherwise, please provide the answer
to be included here.
GnuPG is also useful for signing things. Things that are encrypted with
the secret key can be decrypted with the public key. To sign something, a
hash is taken of the data, and then the hash is in some form encoded with
the secret key. If someone has your public key, they can verify that it
is from you and that it hasn't changed by checking the encoded form of
the hash with the public key.
A keyring is just a large file that stores keys. You have a public keyring
where you store yours and your friend's public keys. You have a secret
keyring that you keep your secret key on, and be very careful with this
secret keyring: Never ever give anyone else access to it and use a *good*
passphrase to protect the data in it.
You can 'conventionally' encrypt something by using the option 'gpg -c'.
It is encrypted using a passphrase, and does not use public and secret
keys. If the person you send the data to knows that passphrase, they can
decrypt it. This is usually most useful for encrypting things to
yourself, although you can encrypt things to your own public key in the
same way. It should be used for communication with partners you know and
where it is easy to exchange the passphrases (e.g. with your boy friend or
your wife). The advantage is that you can change the passphrase from time
to time and decrease the risk, that many old messages may be decrypted by
people who accidently got your passphrase.
You can add and copy keys to and from your keyring with the 'gpg --import'
and 'gpg --export' option. 'gpg --export-secret-keys' will export secret
keys. This is normally not useful, but you can generate the key on one
machine then move it to another machine.
Keys can be signed under the 'gpg --edit-key' option. When you sign a
key, you are saying that you are certain that the key belongs to the
person it says it comes from. You should be very sure that is really
that person: You should verify the key fingerprint
gpg --fingerprint user-id
over phone (if you really know the voice of the other person) or at
a key signing party (which are often held at computer conferences)
or at a meeting of your local GNU/Linux User Group.
Hmm, what else. You may use the option "-o filename" to force output
to this filename (use "-" to force output to stdout). "-r" just lets you
specify the recipient (which public key you encrypt with) on the command
line instead of typing it interactively.
Oh yeah, this is important. By default all data is encrypted in some weird
binary format. If you want to have things appear in ASCII text that is
readable, just add the '-a' option. But the preferred method is to use
a MIME aware mail reader (Mutt, Pine and many more).
There is a small security glitch in the OpenPGP (and therefore GnuPG) system;
to avoid this you should always sign and encrypt a message instead of only
encrypting it.
Q: What is the recommended key size?
A: 1024 bit for DSA signatures; even for plain ElGamal 1. GENERAL
1.1) What is GnuPG?
1.2) Is GnuPG compatible with PGP?
2. SOURCES OF INFORMATION
2.1) Where can I find more information?
2.2) Where do I get GnuPG?
3. INSTALLATION
3.1) Which OSes does GnuPG run on?
3.2) Which random gatherer should I use?
3.3) How do I include support for RSA and IDEA?
4. USAGE
4.1) What is the recommended key size?
4.2) Why does it sometimes take so long to create keys?
4.3) And it really takes long when I work on a remote system. Why?
4.4) What is the difference between options and commands?
4.5) I can't delete an user id because it is already deleted on my public
keying?
4.6) What are trust, validity and ownertrust?
4.7) How do I sign a patch file?
4.8) Where is the "encrypt-to-self" option?
4.9) How can I get rid of the Version and Comment headers in armored
messages?
4.10) What does the "You are using the xxxx character set." mean?
4.11) How can a get list of key IDs used to encrypt a message?
4.12) I can't decrypt my symmetrical only (-c) encrypted message with
a new version of GnuPG.
4.13) How can I used GnuPG in an automated environment?
5. COMPATIBILITY ISSUES
5.1) How can I encrypt a message so that pgp 2.x is able to decrypt it?
5.2) How can I conventional encrypt a message, so that PGP can decrypt
it?
5.3) Why is PGP 5.x not able to encrypt messages with some keys?
5.4) Why is PGP 5.x not able to verify my messages?
5.5) How do I transfer owner trust values from PGP to GnuPG?
5.6) PGP 5.x, 6.x do not like my secret key.
6. PROBLEMS and ERROR MESSAGES
6.1) Why do I get "gpg: Warning: using insecure memory!"
6.2) In the edit menu the trust values is not displayed correctly after
signing uids - why?
6.3) An ElGamal signature does not verify anymore since version 1.0.2 ...
6.4) Old versions of GnuPG can't verify ElGamal signatures
6.5) When I use --clearsign, the plain text has sometimes extra dashes
in it - why?
7. ADVANCED TOPICS
7.1) How does this whole thing work?
7.2) Why are some signatures with an ELG-E key valid?
7.3) How does the whole trust thing work?
7.4) What kind of output is this: "key C26EE891.298, uid 09FB: ...."?
7.5) How do I interpret some of the informational outputs?
7.6) Are the header lines of a cleartext signature part of the signed
material?
8. ACKNOWLEDGEMENTS
1. GENERAL
1.1) What is GnuPG?
GnuPG stands for GNU Privacy Guard and <http://www.gnupg.org>
is GNU's tool for secure communication and data storage.
It can be used to encrypt data and to create digital signatures.
It includes an advanced key management facility and is compliant
with the proposed OpenPGP Internet standard as described in
RFC 2440. As <http://www.gnupg.org/rfc2440.html>
such, it is aimed to be compatible with PGP from NAI Inc.
1.2) Is GnuPG compatible with PGP?
In general, yes. GnuPG and newer PGP releases should be implementing
the OpenPGP standard. But there are some interoperability
problems. See questions 5.1ff. for details.
2. SOURCES OF INFORMATION
2.1) Where can I find more information?
Here's a list of on-line resources:
<http://www.gnupg.org/docs.html> is the
documentation page. Have a look at the HOWTOs and the GNU Privacy
Handbook (GPH, available in English, Spanish and Russian). The
latter provides a detailed user's guide to GnuPG. You'll also find a
document about how to convert from PGP 2.x to GnuPG.
On <http://lists.gnupg.org>
you'll find a searchable online archive of the GnuPG mailing lists.
*PLEASE:*
Before posting to a list, read this FAQ and the available
documentation. This way you help people focus on topics that have
not yet been resolved.
2.2) Where do I get GnuPG?
You can download the GNU Privacy Guard from it's primary FTP server
ftp.gnupg.org or from
one of the mirrors: <http://www.gnupg.org/mirror.html>
3. INSTALLATION
3.1) Which OSes does GnuPG run on?
It should run on most Unices as well as Windows 95 and Windows NT. A
list of OSes reported to be OK is presented at
http://www.gnupg.org/gnupg.html#supsys .
3.2) Which random gatherer should I use?
"Good" random numbers are crucial for the security of your
encryption. Different operating systems provide a variety of more or
less quality random data. Linux and *BSD provide kernel generated
random data through /dev/random - this should be the preferred
choice on these systems. Also Solaris users with the SUNWski package
installed have a /dev/random. In these cases, use the configure
option --enable-static-rnd=linux.
On other systems, the Entropy Gathering Daemon (EGD) is a good
choice. It is a perl-daemon that monitors system activity nad hashes
it into random data. See the download page <http://www.gnupg.org/download.html>
how to obtain egd. Use --enable-static-rnd=egd here.
If the above options do not work, you can use the random number
generator "unix". This is *very* slow and should be
avoided. The random quality isn't very good so don't use it on
sensitive data.
3.3) How do I include support for RSA and IDEA?
The official GnuPG distribution (as of 1.0.2) does not contain
either of them due to patents restriction. The RSA patent expires
Sept 20, 2000. A new GnuPG release is then scheduled to include
it. The IDEA patent does not expire before 2007 so don't expect
official support before then.
However, there are unofficial modules to include both of them even
in earlier version of GnuPG. They're available from
<ftp://ftp.gnupg.org/pub/gcrypt/contrib/>
<ftp://ftp.gnupg.org/pub/gcrypt/contrib/>. Look for idea.c
and rsa.c. Compilation directives are in the headers
of these files. Then add the following lines to your ~/.gnupg/options:
load-extension idea
load-extension rsa
These extensions are not available for the Windows version of GnuPG.
4. USAGE
4.1) What is the recommended key size?
1024 bit for DSA signatures; even for plain ElGamal
signatures this is sufficient as the size of the hash signatures this is sufficient as the size of the hash
is probably the weakest link if the key size is larger is probably the weakest link if the key size is larger
than 1024 bits. Encryption keys may have greater sizes, than 1024 bits. Encryption keys may have greater sizes,
but you should than check the fingerprint of this key: but you should than check the fingerprint of this key:
"gpg --fingerprint --fingerprint <user ID>". "gpg --fingerprint --fingerprint <user ID>".
Q: Why are some signatures with an ELG-E key valid? 4.2) Why does it sometimes take so long to create keys?
A: These are ElGamal Key generated by GnuPG in v3 (rfc1991)
packets. The OpenPGP draft later changed the algorithm
identifier for ElGamal keys which are usable for signatures
and encryption from 16 to 20. GnuPG now uses 20 when it
generates new ElGamal keys but still accept 16 (which is
according to OpenPGP "encryption only") if this key is in
a v3 packet. GnuPG is the only program which had used
these v3 ElGamal keys - so this assumption is quite safe.
Q: Why is PGP 5.x not able to encrypt messages with some keys? The problem here is that we need a lot of random bytes and for that
A: PGP Inc refuses to accept ElGamal keys of type 20 even for
encryption. They only support type 16 (which is identical
at least for decryption). To be more inter-operable, GnuPG
(starting with version 0.3.3) now also uses type 16 for the
ElGamal subkey which is created if the default key algorithm
is chosen. You may add an type 16 ElGamal key to your public
key which is easy as your key signatures are still valid.
Q: Why is PGP 5.x not able to verify my messages?
A: PGP 5.x does not accept V4 signatures for data material but
OpenPGP requires generation of V4 signatures for all kind of
data. Use the option "--force-v3-sigs" to generate V3 signatures
for data.
Q: I can't delete an user id because it is already deleted on my
public keyring?
A: Because you can only select from the public key ring, there is
no direct way to do this. However it is not very complicated
to do it anyway. Create a new user id with exactly the same name
and you will see that there are now two identical user ids on the
secret ring. Now select this user id and delete it. Both user
ids will be removed from the secret ring.
Q: How can I encrypt a message so that pgp 2.x is able to decrypt it?
A: You can't do that because pgp 2.x normally uses IDEA which is not
supported by GnuPG because it is patented, but if you have a modified
version of PGP you can try this:
gpg --rfc1991 --cipher-algo 3des ...
Please don't pipe the data to encrypt to gpg but give it as a filename;
otherwise, pgp 2 will not be able to handle it.
Q: How can I conventional encrypt a message, so that PGP can decrypt it?
A: You can't do this for PGP 2. For PGP 5 you should use this:
gpg -c --cipher-algo 3des --compress-algo 1 myfile
You may replace "3des" by "cast5". "blowfish" does not work with
all versions of pgp5. You may also want to put
compress-algo 1
into your ~/.gnupg/options file - this does not affect normal
gnupg operation.
Q: Why does it sometimes take so long to create keys?
A: The problem here is that we need a lot of random bytes and for that
we (on Linux the /dev/random device) must collect some random data. we (on Linux the /dev/random device) must collect some random data.
It is really not easy to fill the Linux internal entropy buffer; I It is really not easy to fill the Linux internal entropy buffer; I
talked to Ted Ts'o and he commented that the best way to fill the buffer talked to Ted Ts'o and he commented that the best way to fill the
is to play with your keyboard. Good security has its price. What I do buffer is to play with your keyboard. Good security has its price.
is to hit several times on the shift, control, alternate, and capslock What I do is to hit several times on the shift, control, alternate,
keys, because these keys do not produce output to the screen. This way and capslock keys, because these keys do not produce output to the
you get your keys really fast (it's the same thing pgp2 does). screen. This way you get your keys really fast (it's the same thing
pgp2 does).
Another problem might be another program which eats up your random bytes Another problem might be another program which eats up your random
(a program (look at your daemons) that reads from /dev/[u]random). bytes (a program (look at your daemons) that reads from
/dev/[u]random).
Q: And it really takes long when I work on a remote system. Why? 4.3) And it really takes long when I work on a remote system. Why?
A: Don't do this at all! You should never create keys or even use GnuPG
on a remote system because you normally have no physical control over
your secret keyring (which is in most cases vulnerable to advanced
dictionary attacks) - I strongly encourage everyone to only create keys
on a local computer (a disconnected laptop is probably the best choice)
and if you need it on your connected box (I know: We all do this) be
sure to have a strong password for your account and for your secret key
and that you can trust your system administrator.
When I check GnuPG on a remote system via ssh (I have no Alpha here ;-) Don't do this at all! You should never create keys or even use GnuPG
I have the same problem. It takes a *very* long time to create the on a remote system because you normally have no physical control
keys, so I use a special option, --quick-random, to generate insecure over your secret key ring (which is in most cases vulnerable to
keys which are only good for some tests. advanced dictionary attacks) - I strongly encourage everyone to only
create keys on a local computer (a disconnected laptop is probably
the best choice) and if you need it on your connected box (I know:
We all do this) be sure to have a strong password for your account
and for your secret key and that you can trust your system
administrator.
When I check GnuPG on a remote system via ssh (I have no Alpha here
;-) I have the same problem. It takes a *very* long time to create
the keys, so I use a special option, --quick-random, to generate
insecure keys which are only good for some tests.
Q: How does the whole trust thing work? 4.4) What is the difference between options and commands?
A: It works more or less like PGP. The difference is that the trust is
computed at the time it is needed. This is one of the reasons for the
trustdb which holds a list of valid key signatures. If you are not
running in batch mode you will be asked to assign a trust parameter
(ownertrust) to a key.
You can see the validity (calculated trust value) using this command. If you do a 'gpg --help', you will get two separate lists. The first
is a list of commands. The second is a list of options. Whenever you
gpg --list-keys --with-colons run GPG, you *must* pick exactly one command (with one
exception, see below). You *may* pick one or more options.
If the first field is "pub" or "uid", the second field shows you the trust: The command should, just by convention, come at the end of the
argument list, after all the options. If the command takes a file
o = Unknown (this key is new to the system) (all the basic ones do), the filename comes at the very end. So the
e = The key has expired basic way to run gpg is:
q = Undefined (no value assigned)
n = Don't trust this key at all
m = There is marginal trust in this key
f = The key is full trusted
u = The key is ultimately trusted; this
is only used for keys for which
the secret key is also available.
r = The key has been revoked
d = The key has been disabled
The value in the "pub" record is the best one of all "uid" records.
You can get a list of the assigned trust values (how much you trust
the owner to correctly sign another person's key)
gpg --list-ownertrust
The first field is the fingerprint of the primary key, the second field
is the assigned value:
- = No Ownertrust value yet assigned.
n = Never trust this keyholder to correctly verify others signatures.
m = Have marginal trust in the keyholders capability to sign other keys.
f = Assume that the key holder really knows how to sign keys.
u = No need to trust ourself because we have the secret key.
Keep these values confidential because they express your opinions
about others. PGP stores this information with the keyring thus
it is not a good idea to publish a PGP keyring instead of exporting the
keyring. gnupg stores the trust in the trust-DB so it is okay
to give a gpg keyring away (but we have a --export command too).
Q: What is the difference between options and commands?
A: If you do a "gpg --help", you will get two separate lists. The first is
a list of commands. The second is a list of options. Whenever you run GPG,
you *must* pick exactly one command (**with one exception, see below). You
*may* pick one or more options. The command should, just by convention,
come at the end of the argument list, after all the options. If the
command takes a file (all the basic ones do), the filename comes at the
very end. So the basic way to run gpg is:
gpg [--option something] [--option2] [--option3 something] --command file gpg [--option something] [--option2] [--option3 something] --command file
Some options take arguments, for example the --output option (which can be Some options take arguments, for example the --output option (which
abbreviated -o) is an option that takes a filename. The option's argument can be abbreviated -o) is an option that takes a filename. The
must follow immediately after the option itself, otherwise gpg doesn't know option's argument must follow immediately after the option itself,
which option the argument is supposed to go with. As an option, --output and otherwise gpg doesn't know which option the argument is supposed to
its filename must come before the command. The --recipient (-r) option takes go with. As an option, --output and its filename must come before
a name or keyid to encrypt the message to, which must come right after the -r the command. The --recipient (-r) option takes a name or keyid to
argument. The --encrypt (or -e) command comes after all the options followed encrypt the message to, which must come right after the -r argument.
The --encrypt (or -e) command comes after all the options followed
by the file you wish to encrypt. So use by the file you wish to encrypt. So use
gpg -r alice -o secret.txt -e test.txt gpg -r alice -o secret.txt -e test.txt
@ -243,14 +248,14 @@
gpg --recipient alice --output secret.txt --encrypt test.txt gpg --recipient alice --output secret.txt --encrypt test.txt
If you're saving it in a file called ".txt" then you'd probably expect to see If you're saving it in a file called ".txt" then you'd probably
ASCII-armored text in there, so you need to add the --armor (-a) option, expect to see ASCII-armored text in there, so you need to add the
which doesn't take any arguments. --armor (-a) option, which doesn't take any arguments.
gpg --armor --recipient alice --output secret.txt --encrypt test.txt gpg --armor --recipient alice --output secret.txt --encrypt test.txt
If you imagine square brackets around the optional parts, it becomes a bit If you imagine square brackets around the optional parts, it becomes
clearer: a bit clearer:
gpg [--armor] [--recipient alice] [--output secret.txt] --encrypt test.txt gpg [--armor] [--recipient alice] [--output secret.txt] --encrypt test.txt
@ -258,156 +263,398 @@
gpg --output secret.txt --recipient alice --armor --encrypt test.txt gpg --output secret.txt --recipient alice --armor --encrypt test.txt
If your filename begins with a hyphen (e.g. "-a.txt"), gnupg assumes this is If your filename begins with a hyphen (e.g. "-a.txt"), gnupg assumes
an option and may complain. To avoid this you have either to use this is an option and may complain. To avoid this you have either
"./-a.txt" or stop the option and command processing with two hyphens: to use "./-a.txt" or stop the option and command processing with two
"-- -a.txt". hyphens: "-- -a.txt".
** the exception: signing and encrypting at the same time. Use
*The exception:* signing and encrypting at the same time. Use
gpg [--options] --sign --encrypt foo.txt gpg [--options] --sign --encrypt foo.txt
Q: What kind of output is this: "key C26EE891.298, uid 09FB: ...."? 4.5) I can't delete an user id because it is already deleted on my public
A: This is the internal representation of an user id in the trustdb. keying?
"C26EE891" is the keyid, "298" is the local id (a record number
in the trustdb) and "09FB" is the last two bytes of a ripe-md-160
hash of the user id for this key.
Because you can only select from the public key ring, there is no
direct way to do this. However it is not very complicated to do it
anyway. Create a new user id with exactly the same name and you
will see that there are now two identical user ids on the secret
ring. Now select this user id and delete it. Both user ids will be
removed from the secret ring.
Q: What is trust, validity and ownertrust? 4.6) What are trust, validity and ownertrust?
A: "ownertrust" is used instead of "trust" to make clear that
this is the value you have assigned to a key to express how much you
trust the owner of this key to correctly sign (and so introduce)
other keys. "validity", or calculated trust, is a value which
says how much GnuPG thinks a key is valid (that it really belongs
to the one who claims to be the owner of the key).
For more see the chapter "The Web of Trust" in the Manual.
Q: How do I interpret some of the informational outputs? "ownertrust" is used instead of "trust" to make clear that this is
A: While checking the validity of a key, GnuPG sometimes prints the value you have assigned to a key to express how much you trust
some information which is prefixed with information about the owner of this key to correctly sign (and so introduce) other
the checked item. keys. "validity", or calculated trust, is a value which says how
"key 12345678.3456" much GnuPG thinks a key is valid (that it really belongs to the one
This is about the key with key ID 12345678 and the internal who claims to be the owner of the key). For more see the chapter
number 3456, which is the record number of the so called "The Web of Trust" in the Manual.
directory record in the trustdb.
"uid 12345678.3456/ACDE"
This is about the user ID for the same key. To identify the
user ID the last two bytes of a ripe-md-160 over the user ID
ring is printed.
"sig 12345678.3456/ACDE/9A8B7C6D"
This is about the signature with key ID 9A8B7C6D for the
above key and user ID, if it is a signature which is direct
on a key, the user ID part is empty (..//..).
4.7) How do I sign a patch file?
Q: How do I sign a patch file? Use "gpg --clearsign --not-dash-escaped ...". The problem with
A: Use "gpg --clearsign --not-dash-escaped ...". --clearsign is that all lines starting with a dash are quoted with
The problem with --clearsign is that all lines starting with a dash are "- "; obviously diff produces many of lines starting with a dash and
quoted with "- "; obviously diff produces many of lines starting with a these are then quoted and that is not good for patch ;-). To use a
dash and these are then quoted and that is not good for patch ;-). To patch file without removing the cleartext signature, the special
use a patch file without removing the cleartext signature, the special option --not-dash-escaped may be used to suppress generation of
option --not-dash-escaped may be used to suppress generation of these these escape sequences. You should not mail such a patch because
escape sequences. You should not mail such a patch because spaces and spaces and line endings are also subject to the signature and a
line endings are also subject to the signature and a mailer may not mailer may not preserve these. If you want to mail a file you can
preserve these. If you want to mail a file you can simply sign it simply sign it using your MUA.
using your MUA.
4.8) Where is the "encrypt-to-self" option?
Q: Where is the "encrypt-to-self" option? Use "--encrypt-to your_keyid". You can use more than one of these
A: Use "--encrypt-to your_keyid". You can use more than one options. To temporary override the use of this additional keys, you
of these options. To temporary override the use of this additional can use the option "--no-encrypt-to".
keys, you can use the option "--no-encrypt-to".
4.9) How can I get rid of the Version and Comment headers in armored
messages?
Q: How can I get rid of the Version and Comment headers in Use "--no-version --comment ''". Note that the left over blank line
armored messages?
A: Use "--no-version --comment ''". Note that the left over blank line
is required by the protocol. is required by the protocol.
4.10) What does the "You are using the xxxx character set." mean?
Q: What does the "You are using the xxxx character set." mean? This note is printed when UTF8 mapping has to be done. Make sure
A: This note is printed when UTF8 mapping has to be done. Make sure that that the displayed charset is the one you have activated on your
the displayed charset is the one you have activated on your system system "iso-8859-1" is the most used one, so this is the default.
"iso-8859-1" is the most used one, so this is the default. You can You can change the charset with the option "--charset". It is
change the charset with the option "--charset". It is important that important that you active character set matches the one displayed -
you active character set matches the one displayed - if not, restrict if not, restrict yourself to plain 7 bit ASCII and no mapping has to
yourself to plain 7 bit ASCII and no mapping has to be done. be done.
Q: How do I transfer owner trust values from PGP to GnuPG? 4.11) How can a get list of key IDs used to encrypt a message?
A: There is a script in the tools directory to help you:
After you have imported the PGP keyring you can give this command:
$ lspgpot pgpkeyring | gpg --import-ownertrust
where pgpkeyring is the original keyring and not the GnuPG one you
might have created in the first step.
Q: Are the headerlines of a cleartext signature part of the signed gpg --batch --decrypt --list-only --status-fd 1 2>/dev/null
material? \ | awk '/^\[GNUPG:\] ENC_TO / { print $3 }'
A: No. For example you can add or remove "Comment:" lines. They
have a purpose like the mail header lines. However a "Hash:"
line is needed for OpenPGG signatures to tell the parser which
hash algorithm to use.
Q: How can a get list of key IDs used to encrypt a message? 4.12) I can't decrypt my symmetrical only (-c) encrypted message with
A: gpg --batch --decrypt --list-only --status-fd 1 2>/dev/null \
| awk '/^\[GNUPG:\] ENC_TO / { print $3 }'
Q: PGP 5.x, 6.x does not like my secret key.
A: PGP probably bails out on some private comment packets used by GnuPG.
These packets are fully in compliance with OpenPGP; however PGP is not
really OpenPGP aware. A workaround is to export the secret keys with
this command:
gpg --export-secret-keys --no-comment -a your-key-id
Q: I can't decrypt my symmetrical only (-c) encrypted message with
a new version of GnuPG. a new version of GnuPG.
A: There used to be a bug in GnuPG < 1.0.1 which happens only if 3DES or
Twofish has been used for symmetric only encryption (this has never been
the default).
The bug has been fixed but to enable you to decrypt old messages, you
should run gpg with the option "--emulate-3des-s2k-bug", decrypt the
message and encrypt it again without this option. The option will
be removed in 1.1, so better re-encrypt your message now.
Q: How can I used GnuPG in an automated environment? There used to be a bug in GnuPG < 1.0.1 which happens only if 3DES
A: You should use the option --batch and don't use passphrases as or Twofish has been used for symmetric only encryption (this has
never been the default). The bug has been fixed but to enable you
to decrypt old messages, you should run gpg with the option
"--emulate-3des-s2k-bug", decrypt the message and encrypt it again
without this option. The option will be removed in 1.1, so better
re-encrypt your message now.
4.13) How can I used GnuPG in an automated environment?
You should use the option --batch and don't use pass phrases as
there is usually no way to store it more secure than the secret there is usually no way to store it more secure than the secret
keyring itself. The suggested way to create the keys for the keyring itself. The suggested way to create the keys for the
automated environment is: automated environment is:
On a secure machine: On a secure machine:
1. If you want to do automatic signing, create a signing subkey If you want to do automatic signing, create a signing
for your key (edit menu, choose "addkey" and the DSA). subkey for your key (edit menu, choose "addkey" and the DSA). [H
2. Make sure that you use a passphrase (Needed by the current LI] Make sure that you use a passphrase (Needed by the current
implementation) implementation) gpg --export-secret-subkeys --no-comment foo
3. gpg --export-secret-subkeys --no-comment foo >secring.auto >secring.auto Copy secring.auto and the public keyring to a
4. Copy secring.auto and the public keyring to a test directory. test directory. Cd to this directory. gpg --homedir
5. Cd to this directory. . --edit foo and use "passwd" to remove the pass-phrase from the
6. gpg --homedir . --edit foo subkeys. You may also want to remove all unused subkeys.
and use "passwd" to remove the passphrase from the subkeys. copy secring.auto to a floppy and carry it to the target box
You may also want to remove all unused subkeys. On the target machine: Install secring.auto as secret
7. copy secring.auto to a floppy and carry it to the keyring. Now you can start your new service. It is a good
target box idea to install some intrusion detection system so that you
On the target machine: hopefully get a notice of an successful intrusion, so that you in
8. Install secring.auto as secret keyring. turn can revoke all the subkeys installed on that machine and
9. Now you can start your new service. It is a good idea to install new subkeys.
install some intrusion detection system so that you hopefully
get a notice of an successful intrusion, so that you in turn can
revoke all the subkeys installed on that machine and install new
subkeys.
Q: In the edit menu the trust values is not displayed correctly after
5. COMPATIBILITY ISSUES
5.1) How can I encrypt a message so that pgp 2.x is able to decrypt it?
You can't do that because pgp 2.x normally uses IDEA which is not
supported by GnuPG because it is patented, but if you have a
modified version of PGP you can try this:
gpg --rfc1991 --cipher-algo 3des ...
Please don't pipe the data to encrypt to gpg but give it as a
filename; otherwise, pgp 2 will not be able to handle it.
5.2) How can I conventional encrypt a message, so that PGP can decrypt
it?
You can't do this for PGP 2. For PGP 5 you should use this:
gpg -c --cipher-algo 3des --compress-algo 1 myfile
You may replace "3des" by "cast5". "blowfish" does not work with all
versions of pgp5. You may also want to put compress-algo 1
into your ~/.gnupg/options file - this does not affect
normal gnupg operation.
5.3) Why is PGP 5.x not able to encrypt messages with some keys?
PGP Inc refuses to accept ElGamal keys of type 20 even for
encryption. They only support type 16 (which is identical at least
for decryption). To be more inter-operable, GnuPG (starting with
version 0.3.3) now also uses type 16 for the ElGamal subkey which is
created if the default key algorithm is chosen. You may add an type
16 ElGamal key to your public key which is easy as your key
signatures are still valid.
5.4) Why is PGP 5.x not able to verify my messages?
PGP 5.x does not accept V4 signatures for data material but OpenPGP
requires generation of V4 signatures for all kind of data. Use the
option "--force-v3-sigs" to generate V3 signatures for data.
5.5) How do I transfer owner trust values from PGP to GnuPG?
There is a script in the tools directory to help you: After you have
imported the PGP keyring you can give this command:
$ lspgpot pgpkeyring | gpg --import-ownertrust
where pgpkeyring is the original keyring and not the GnuPG one you
might have created in the first step.
5.6) PGP 5.x, 6.x do not like my secret key.
PGP probably bails out on some private comment packets used by
GnuPG. These packets are fully in compliance with OpenPGP; however
PGP is not really OpenPGP aware. A workaround is to export the
secret keys with this command:
gpg --export-secret-keys --no-comment -a your-key-id
6. PROBLEMS and ERROR MESSAGES
6.1) Why do I get "gpg: Warning: using insecure memory!"
On many systems this program should be installed as
setuid(root). This is necessary to lock memory pages. Locking
memory pages prevents the operating system from writing memory pages
to disk and thereby keeping your secret keys really secret. If you
get no warning message about insecure memory your operating system
supports locking without being root. The program drops root
privileges as soon as locked memory is allocated.
If you can't or don't want to install GnuPG setuid(root), you can
use the option "--no-secmem-warning" or put
no-secmem-warning in your ~/.gnupg/options file.
6.2) In the edit menu the trust values is not displayed correctly after
signing uids - why? signing uids - why?
A: This happens because the some informations are stored immediately
in the trustdb, but the actual trust calculation can be done after
the save command. This is a not easy to fix design bug which will be
addressed in GnuPG 1.1
Q: An Elgamal signature does not verify anymore since version 1.0.2 This happens because the some informations are stored immediately in
A: Use the option --emulate-md-encode-bug. the trustdb, but the actual trust calculation can be done after the
save command. This is a not easy to fix design bug which will be
addressed in some future release.
Q: Old versions of GnuPG can't verify ElGamal signatures 6.3) An ElGamal signature does not verify anymore since version 1.0.2 ...
A: Update to GnuPG 1.0.2
Use the option --emulate-md-encode-bug.
6.4) Old versions of GnuPG can't verify ElGamal signatures
Update to GnuPG 1.0.2 or newer.
6.5) When I use --clearsign, the plain text has sometimes extra dashes
in it - why?
This is called dash-escaped text and required by OpenPGP.
It always happens when a line starts with a dash ("-") and is needed
to distinguish those lines from the thos lines which make up such
a clearsigned message.
If you use GnuPG to process those emessage, the extra dashes are removed.
Good mail clients remove those extra dashes when displaying such a
message.
7. ADVANCED TOPICS
7.1) How does this whole thing work?
To generate a secret/public keypair, run gpg --gen-key
and choose the default values.
Data that is encrypted with a public key can only be decrypted by
the matching secret key. The secret key is protected by a password,
the public key is not.
So to send your friend a message, you would encrypt your message
with his public key, and he would only be able to decrypt it by
having the secret key and putting in the password to use his secret
key.
GnuPG is also useful for signing things. Things that are encrypted
with the secret key can be decrypted with the public key. To sign
something, a hash is taken of the data, and then the hash is in some
form encoded with the secret key. If someone has your public key, they
can verify that it is from you and that it hasn't changed by checking
the encoded form of the hash with the public key.
A keyring is just a large file that stores keys. You have a public
keyring where you store yours and your friend's public keys. You have
a secret keyring that you keep your secret key on, and be very careful
with this secret keyring: Never ever give anyone else access to it and
use a *good* passphrase to protect the data in it.
You can 'conventionally' encrypt something by using the option 'gpg
-c'. It is encrypted using a passphrase, and does not use public and
secret keys. If the person you send the data to knows that
passphrase, they can decrypt it. This is usually most useful for
encrypting things to yourself, although you can encrypt things to your
own public key in the same way. It should be used for communication
with partners you know and where it is easy to exchange the
passphrases (e.g. with your boy friend or your wife). The advantage
is that you can change the passphrase from time to time and decrease
the risk, that many old messages may be decrypted by people who
accidently got your passphrase.
You can add and copy keys to and from your keyring with the 'gpg
--import' and 'gpg --export' option. 'gpg --export-secret-keys' will
export secret keys. This is normally not useful, but you can generate
the key on one machine then move it to another machine.
Keys can be signed under the 'gpg --edit-key' option. When you sign a
key, you are saying that you are certain that the key belongs to the
person it says it comes from. You should be very sure that is really
that person: You should verify the key fingerprint
gpg --fingerprint user-id
over phone (if you really know the voice of the other person) or at a
key signing party (which are often held at computer conferences) or at
a meeting of your local GNU/Linux User Group.
Hmm, what else. You may use the option "-o filename" to force output
to this filename (use "-" to force output to stdout). "-r" just lets
you specify the recipient (which public key you encrypt with) on the
command line instead of typing it interactively.
Oh yeah, this is important. By default all data is encrypted in some
weird binary format. If you want to have things appear in ASCII text
that is readable, just add the '-a' option. But the preferred method
is to use a MIME aware mail reader (Mutt, Pine and many more).
There is a small security glitch in the OpenPGP (and therefore GnuPG)
system; to avoid this you should always sign and encrypt a message
instead of only encrypting it.
7.2) Why are some signatures with an ELG-E key valid?
These are ElGamal Key generated by GnuPG in v3 (rfc1991) packets.
The OpenPGP draft later changed the algorithm identifier for ElGamal
keys which are usable for signatures and encryption from 16 to 20.
GnuPG now uses 20 when it generates new ElGamal keys but still
accept 16 (which is according to OpenPGP "encryption only") if this
key is in a v3 packet. GnuPG is the only program which had used
these v3 ElGamal keys - so this assumption is quite safe.
7.3) How does the whole trust thing work?
It works more or less like PGP. The difference is that the trust is
computed at the time it is needed. This is one of the reasons for
the trustdb which holds a list of valid key signatures. If you are
not running in batch mode you will be asked to assign a trust
parameter (ownertrust) to a key.
You can see the validity (calculated trust value) using this
command.
gpg --list-keys --with-colons
If the first field is "pub" or "uid", the second field shows you the
trust:
o = Unknown (this key is new to the system)
e = The key has expired
q = Undefined (no value assigned)
n = Don't trust this key at all
m = There is marginal trust in this key
f = The key is full trusted
u = The key is ultimately trusted; this is only used
for keys for which the secret key is also available.
r = The key has been revoked
d = The key has been disabled
The value in the "pub" record is the best one of all "uid" records.
You can get a list of the assigned trust values (how much you trust
the owner to correctly sign another person's key)
gpg --list-ownertrust The first field is the
fingerprint of the primary key, the second field is the assigned
value:
- = No Ownertrust value yet assigned.
n = Never trust this keyholder to correctly verify others signatures.
m = Have marginal trust in the keyholders capability to sign other
keys.
f = Assume that the key holder really knows how to sign keys.
u = No need to trust ourself because we have the secret key.
Keep these values confidential because they express your opinions
about others. PGP stores this information with the keyring thus it
is not a good idea to publish a PGP keyring instead of exporting the
keyring. gnupg stores the trust in the trust-DB so it is okay to
give a gpg keyring away (but we have a --export command too).
7.4) What kind of output is this: "key C26EE891.298, uid 09FB: ...."?
This is the internal representation of an user id in the trustdb.
"C26EE891" is the keyid, "298" is the local id (a record number in
the trustdb) and "09FB" is the last two bytes of a ripe-md-160 hash
of the user id for this key.
7.5) How do I interpret some of the informational outputs?
While checking the validity of a key, GnuPG sometimes prints some
information which is prefixed with information about the checked
item. "key 12345678.3456" This is about the key
with key ID 12345678 and the internal number 3456, which is the
record number of the so called directory record in the trustdb.
"uid 12345678.3456/ACDE" This is about the user ID for
the same key. To identify the user ID the last two bytes of a
ripe-md-160 over the user ID ring is printed. "sig
12345678.3456/ACDE/9A8B7C6D" This is about the signature
with key ID 9A8B7C6D for the above key and user ID, if it is a
signature which is direct on a key, the user ID part is empty
(..//..).
7.6) Are the header lines of a cleartext signature part of the signed
material?
No. For example you can add or remove "Comment:" lines. They have
a purpose like the mail header lines. However a "Hash:" line is
needed for OpenPGP signatures to tell the parser which hash
algorithm to use.
8. ACKNOWLEDGEMENTS
Many thanks to Werner Koch for the original FAQ file and to all
posters to gnupg-users and gnupg-devel. They all provided most of
the answers.
Also thanks to Casper Dik for providing me with a script to generate
this FAQ (he uses it for the excellent Solaris2 FAQ).
Copyright (C) 2000 Free Software Foundation, Inc. ,
59 Temple Place - Suite 330, Boston, MA 02111, USA
Verbatim copying and distribution of this entire article is permitted in
any medium, provided this notice is preserved.

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EXTRA_DIST = DETAILS gpg.sgml gpg.1 FAQ HACKING OpenPGP README.W32 EXTRA_DIST = DETAILS gpg.sgml gpg.1 faq.raw \
HACKING OpenPGP README.W32
man_MANS = gpg.1 man_MANS = gpg.1
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[$htmltitle=GnuPG FAQ]
[$sfaqheader=The GnuPG FAQ says:]
[$sfaqfooter=
The most recent version of the FAQ is available from
<http://www.gnupg.org/>
]
[$usenetheader=
]
[$maintainer=Nils Ellmenreich <nils 'at' infosun.fmi.uni-passau.de>]
[$WINS=.wins.uva.nl/pub/solaris]
[$ftpWINS=ftp://ftp.wins.uva.nl/pub/solaris]
[$hWINS=http://www.wins.uva.nl/]
[$fhWINS=http://www.wins.uva.nl/pub/solaris/solaris2]
[$hGPG=http://www.gnupg.org]
[H H1]GNUPG FREQUENTLY ASKED QUESTIONS[H /H1]
[H pre]
Version: 0.1
Last-Modified: Sep 14, 2000
Maintained-by: [$maintainer]
[H/pre]
This is the GnuPG FAQ. The latest HTML version is available
[H a href=[$hGPG]] here[H/a].
The index is generated automatically, so there may be errors here. Not
all questions may be in the section they belong to. Suggestions about
how to improve the structure of this FAQ are welcome.
Please send additions and corrections to the maintainer. Don't send
message like "This should be a FAQ - what's the answer?". If it hasn't
been asked before, it isn't a FAQ. Otherwise, please provide the answer
to be included here.
[H HR]
<C>
[H HR]
<S> GENERAL
<Q> What is GnuPG?
[H a href=[$hGPG]]GnuPG[H /a] stands for GNU Privacy Guard and
is GNU's tool for secure communication and data storage.
It can be used to encrypt data and to create digital signatures.
It includes an advanced key management facility and is compliant
with the proposed OpenPGP Internet standard as described in
[H a href=http://www.gnupg.org/rfc2440.html]RFC 2440[H/a]. As
such, it is aimed to be compatible with PGP from NAI Inc.
<Q> Is GnuPG compatible with PGP?
In general, yes. GnuPG and newer PGP releases should be implementing
the OpenPGP standard. But there are some interoperability
problems. See questions <Rcompat>ff. for details.
<S> SOURCES OF INFORMATION
<Q> Where can I find more information?
Here's a list of on-line resources: [H UL]
[H LI] [H a href=[$hGPG]/docs.html]<[$hGPG]/docs.html>[H/a] is the
documentation page. Have a look at the HOWTOs and the GNU Privacy
Handbook (GPH, available in English, Spanish and Russian). The
latter provides a detailed user's guide to GnuPG. You'll also find a
document about how to convert from PGP 2.x to GnuPG.
[H LI] On [H a href=http://lists.gnupg.org]<http://lists.gnupg.org>[H/a]
you'll find a searchable online archive of the GnuPG mailing lists.
[H B]PLEASE:[H/B]
Before posting to a list, read this FAQ and the available
documentation. This way you help people focus on topics that have
not yet been resolved.
[H /UL]
<Q> Where do I get GnuPG?
You can download the GNU Privacy Guard from it's primary FTP server
[H a href=ftp://ftp.gnupg.org/pub/gcrypt]ftp.gnupg.org[H /a] or from
one of the mirrors: [H a href=[$hGPG]/mirrors.html]<[$hGPG]/mirror.html>[H /a]
<S> INSTALLATION
<Q> Which OSes does GnuPG run on?
It should run on most Unices as well as Windows 95 and Windows NT. A
list of OSes reported to be OK is presented at
[H a href=http://www.gnupg.org/gnupg.html#supsys]
http://www.gnupg.org/gnupg.html#supsys [H /a].
<Q> Which random gatherer should I use?
"Good" random numbers are crucial for the security of your
encryption. Different operating systems provide a variety of more or
less quality random data. Linux and *BSD provide kernel generated
random data through /dev/random - this should be the preferred
choice on these systems. Also Solaris users with the SUNWski package
installed have a /dev/random. In these cases, use the configure
option [H pre]--enable-static-rnd=linux[H/pre].
On other systems, the Entropy Gathering Daemon (EGD) is a good
choice. It is a perl-daemon that monitors system activity nad hashes
it into random data. See the download page [H a href=http://www.gnupg.org/download.html]<http://www.gnupg.org/download.html>[H /a]
how to obtain egd. Use [H pre]--enable-static-rnd=egd[H/pre] here.
If the above options do not work, you can use the random number
generator "unix". This is [H B]very[H /B] slow and should be
avoided. The random quality isn't very good so don't use it on
sensitive data.
<Q> How do I include support for RSA and IDEA?
The official GnuPG distribution (as of 1.0.2) does not contain
either of them due to patents restriction. The RSA patent expires
Sept 20, 2000. A new GnuPG release is then scheduled to include
it. The IDEA patent does not expire before 2007 so don't expect
official support before then.
However, there are unofficial modules to include both of them even
in earlier version of GnuPG. They're available from [H a href=ftp://ftp.gnupg.org/pub/gcrypt/contrib/]
<ftp://ftp.gnupg.org/pub/gcrypt/contrib/>[H /a]. Look for [H pre]idea.c[H /pre]
and [H pre]rsa.c[H /pre]. Compilation directives are in the headers
of these files. Then add the following lines to your ~/.gnupg/options:
[H pre]
load-extension idea
load-extension rsa
[H /pre]
These extensions are not available for the Windows version of GnuPG.
<S> USAGE
<Q> What is the recommended key size?
1024 bit for DSA signatures; even for plain ElGamal
signatures this is sufficient as the size of the hash
is probably the weakest link if the key size is larger
than 1024 bits. Encryption keys may have greater sizes,
but you should than check the fingerprint of this key:
"gpg --fingerprint --fingerprint <user ID>".
<Q> Why does it sometimes take so long to create keys?
The problem here is that we need a lot of random bytes and for that
we (on Linux the /dev/random device) must collect some random data.
It is really not easy to fill the Linux internal entropy buffer; I
talked to Ted Ts'o and he commented that the best way to fill the
buffer is to play with your keyboard. Good security has its price.
What I do is to hit several times on the shift, control, alternate,
and capslock keys, because these keys do not produce output to the
screen. This way you get your keys really fast (it's the same thing
pgp2 does).
Another problem might be another program which eats up your random
bytes (a program (look at your daemons) that reads from
/dev/[u]random).
<Q> And it really takes long when I work on a remote system. Why?
Don't do this at all! You should never create keys or even use GnuPG
on a remote system because you normally have no physical control
over your secret key ring (which is in most cases vulnerable to
advanced dictionary attacks) - I strongly encourage everyone to only
create keys on a local computer (a disconnected laptop is probably
the best choice) and if you need it on your connected box (I know:
We all do this) be sure to have a strong password for your account
and for your secret key and that you can trust your system
administrator.
When I check GnuPG on a remote system via ssh (I have no Alpha here
;-) I have the same problem. It takes a *very* long time to create
the keys, so I use a special option, --quick-random, to generate
insecure keys which are only good for some tests.
<Q> What is the difference between options and commands?
If you do a 'gpg --help', you will get two separate lists. The first
is a list of commands. The second is a list of options. Whenever you
run GPG, you [H B]must[H /B] pick exactly one command (with one
exception, see below). You [H B]may[H /B] pick one or more options.
The command should, just by convention, come at the end of the
argument list, after all the options. If the command takes a file
(all the basic ones do), the filename comes at the very end. So the
basic way to run gpg is:
[H pre]
gpg [--option something] [--option2] [--option3 something] --command file
[H/pre]
Some options take arguments, for example the --output option (which
can be abbreviated -o) is an option that takes a filename. The
option's argument must follow immediately after the option itself,
otherwise gpg doesn't know which option the argument is supposed to
go with. As an option, --output and its filename must come before
the command. The --recipient (-r) option takes a name or keyid to
encrypt the message to, which must come right after the -r argument.
The --encrypt (or -e) command comes after all the options followed
by the file you wish to encrypt. So use
[H pre]
gpg -r alice -o secret.txt -e test.txt
[H/pre]
If you write the options out in full, it is easier to read
[H pre]
gpg --recipient alice --output secret.txt --encrypt test.txt
[H/pre]
If you're saving it in a file called ".txt" then you'd probably
expect to see ASCII-armored text in there, so you need to add the
--armor (-a) option, which doesn't take any arguments.
[H pre]
gpg --armor --recipient alice --output secret.txt --encrypt test.txt
[H/pre]
If you imagine square brackets around the optional parts, it becomes
a bit clearer:
[H pre]
gpg [--armor] [--recipient alice] [--output secret.txt] --encrypt test.txt
[H/pre]
The optional parts can be rearranged any way you want.
[H pre]
gpg --output secret.txt --recipient alice --armor --encrypt test.txt
[H/pre]
If your filename begins with a hyphen (e.g. "-a.txt"), gnupg assumes
this is an option and may complain. To avoid this you have either
to use "./-a.txt" or stop the option and command processing with two
hyphens: "-- -a.txt".
[H B]The exception:[H /B] signing and encrypting at the same time. Use
[H pre] gpg [--options] --sign --encrypt foo.txt [H/pre]
<Q> I can't delete an user id because it is already deleted on my public
keying?
Because you can only select from the public key ring, there is no
direct way to do this. However it is not very complicated to do it
anyway. Create a new user id with exactly the same name and you
will see that there are now two identical user ids on the secret
ring. Now select this user id and delete it. Both user ids will be
removed from the secret ring.
<Q> What are trust, validity and ownertrust?
"ownertrust" is used instead of "trust" to make clear that this is
the value you have assigned to a key to express how much you trust
the owner of this key to correctly sign (and so introduce) other
keys. "validity", or calculated trust, is a value which says how
much GnuPG thinks a key is valid (that it really belongs to the one
who claims to be the owner of the key). For more see the chapter
"The Web of Trust" in the Manual.
<Q> How do I sign a patch file?
Use "gpg --clearsign --not-dash-escaped ...". The problem with
--clearsign is that all lines starting with a dash are quoted with
"- "; obviously diff produces many of lines starting with a dash and
these are then quoted and that is not good for patch ;-). To use a
patch file without removing the cleartext signature, the special
option --not-dash-escaped may be used to suppress generation of
these escape sequences. You should not mail such a patch because
spaces and line endings are also subject to the signature and a
mailer may not preserve these. If you want to mail a file you can
simply sign it using your MUA.
<Q> Where is the "encrypt-to-self" option?
Use "--encrypt-to your_keyid". You can use more than one of these
options. To temporary override the use of this additional keys, you
can use the option "--no-encrypt-to".
<Q> How can I get rid of the Version and Comment headers in armored
messages?
Use "--no-version --comment ''". Note that the left over blank line
is required by the protocol.
<Q> What does the "You are using the xxxx character set." mean?
This note is printed when UTF8 mapping has to be done. Make sure
that the displayed charset is the one you have activated on your
system "iso-8859-1" is the most used one, so this is the default.
You can change the charset with the option "--charset". It is
important that you active character set matches the one displayed -
if not, restrict yourself to plain 7 bit ASCII and no mapping has to
be done.
<Q> How can a get list of key IDs used to encrypt a message?
[H pre] gpg --batch --decrypt --list-only --status-fd 1 2>/dev/null
\ | awk '/^\[GNUPG:\] ENC_TO / { print $3 }' [H /pre]
<Q> I can't decrypt my symmetrical only (-c) encrypted message with
a new version of GnuPG.
There used to be a bug in GnuPG < 1.0.1 which happens only if 3DES
or Twofish has been used for symmetric only encryption (this has
never been the default). The bug has been fixed but to enable you
to decrypt old messages, you should run gpg with the option
"--emulate-3des-s2k-bug", decrypt the message and encrypt it again
without this option. The option will be removed in 1.1, so better
re-encrypt your message now.
<Q> How can I used GnuPG in an automated environment?
You should use the option --batch and don't use pass phrases as
there is usually no way to store it more secure than the secret
keyring itself. The suggested way to create the keys for the
automated environment is:
On a secure machine:
[H OL] [H LI] If you want to do automatic signing, create a signing
subkey for your key (edit menu, choose "addkey" and the DSA). [H
LI] Make sure that you use a passphrase (Needed by the current
implementation) [H LI] gpg --export-secret-subkeys --no-comment foo
>secring.auto [H LI] Copy secring.auto and the public keyring to a
test directory. [H LI] Cd to this directory. [H LI] gpg --homedir
. --edit foo and use "passwd" to remove the pass-phrase from the
subkeys. You may also want to remove all unused subkeys. [H LI]
copy secring.auto to a floppy and carry it to the target box [H /OL]
On the target machine: [H OL] [H LI] Install secring.auto as secret
keyring. [H LI] Now you can start your new service. It is a good
idea to install some intrusion detection system so that you
hopefully get a notice of an successful intrusion, so that you in
turn can revoke all the subkeys installed on that machine and
install new subkeys. [H /OL]
<S> COMPATIBILITY ISSUES
<Dcompat>
<Q> How can I encrypt a message so that pgp 2.x is able to decrypt it?
You can't do that because pgp 2.x normally uses IDEA which is not
supported by GnuPG because it is patented, but if you have a
modified version of PGP you can try this:
[H pre] gpg --rfc1991 --cipher-algo 3des ... [H/pre]
Please don't pipe the data to encrypt to gpg but give it as a
filename; otherwise, pgp 2 will not be able to handle it.
<Q> How can I conventional encrypt a message, so that PGP can decrypt
it?
You can't do this for PGP 2. For PGP 5 you should use this:
[H pre]
gpg -c --cipher-algo 3des --compress-algo 1 myfile
[H/pre]
You may replace "3des" by "cast5". "blowfish" does not work with all
versions of pgp5. You may also want to put [H pre] compress-algo 1
[H/pre] into your ~/.gnupg/options file - this does not affect
normal gnupg operation.
<Q> Why is PGP 5.x not able to encrypt messages with some keys?
PGP Inc refuses to accept ElGamal keys of type 20 even for
encryption. They only support type 16 (which is identical at least
for decryption). To be more inter-operable, GnuPG (starting with
version 0.3.3) now also uses type 16 for the ElGamal subkey which is
created if the default key algorithm is chosen. You may add an type
16 ElGamal key to your public key which is easy as your key
signatures are still valid.
<Q> Why is PGP 5.x not able to verify my messages?
PGP 5.x does not accept V4 signatures for data material but OpenPGP
requires generation of V4 signatures for all kind of data. Use the
option "--force-v3-sigs" to generate V3 signatures for data.
<Q> How do I transfer owner trust values from PGP to GnuPG?
There is a script in the tools directory to help you: After you have
imported the PGP keyring you can give this command:
[H pre]
$ lspgpot pgpkeyring | gpg --import-ownertrust
[H /pre]
where pgpkeyring is the original keyring and not the GnuPG one you
might have created in the first step.
<Q> PGP 5.x, 6.x do not like my secret key.
PGP probably bails out on some private comment packets used by
GnuPG. These packets are fully in compliance with OpenPGP; however
PGP is not really OpenPGP aware. A workaround is to export the
secret keys with this command:
[H pre] gpg --export-secret-keys --no-comment -a your-key-id [H /pre]
<S> PROBLEMS and ERROR MESSAGES
<Q> Why do I get "gpg: Warning: using insecure memory!"
On many systems this program should be installed as
setuid(root). This is necessary to lock memory pages. Locking
memory pages prevents the operating system from writing memory pages
to disk and thereby keeping your secret keys really secret. If you
get no warning message about insecure memory your operating system
supports locking without being root. The program drops root
privileges as soon as locked memory is allocated.
If you can't or don't want to install GnuPG setuid(root), you can
use the option "--no-secmem-warning" or put [H pre]
no-secmem-warning [H /pre] in your ~/.gnupg/options file.
<Q> In the edit menu the trust values is not displayed correctly after
signing uids - why?
This happens because the some informations are stored immediately in
the trustdb, but the actual trust calculation can be done after the
save command. This is a not easy to fix design bug which will be
addressed in some future release.
<Q> An ElGamal signature does not verify anymore since version 1.0.2 ...
Use the option --emulate-md-encode-bug.
<Q> Old versions of GnuPG can't verify ElGamal signatures
Update to GnuPG 1.0.2 or newer.
<Q> When I use --clearsign, the plain text has sometimes extra dashes
in it - why?
This is called dash-escaped text and required by OpenPGP.
It always happens when a line starts with a dash ("-") and is needed
to distinguish those lines from the thos lines which make up such
a clearsigned message.
If you use GnuPG to process those emessage, the extra dashes are removed.
Good mail clients remove those extra dashes when displaying such a
message.
<S> ADVANCED TOPICS
<Q> How does this whole thing work?
To generate a secret/public keypair, run [H pre] gpg --gen-key
[H/pre] and choose the default values.
Data that is encrypted with a public key can only be decrypted by
the matching secret key. The secret key is protected by a password,
the public key is not.
So to send your friend a message, you would encrypt your message
with his public key, and he would only be able to decrypt it by
having the secret key and putting in the password to use his secret
key.
GnuPG is also useful for signing things. Things that are encrypted
with the secret key can be decrypted with the public key. To sign
something, a hash is taken of the data, and then the hash is in some
form encoded with the secret key. If someone has your public key, they
can verify that it is from you and that it hasn't changed by checking
the encoded form of the hash with the public key.
A keyring is just a large file that stores keys. You have a public
keyring where you store yours and your friend's public keys. You have
a secret keyring that you keep your secret key on, and be very careful
with this secret keyring: Never ever give anyone else access to it and
use a *good* passphrase to protect the data in it.
You can 'conventionally' encrypt something by using the option 'gpg
-c'. It is encrypted using a passphrase, and does not use public and
secret keys. If the person you send the data to knows that
passphrase, they can decrypt it. This is usually most useful for
encrypting things to yourself, although you can encrypt things to your
own public key in the same way. It should be used for communication
with partners you know and where it is easy to exchange the
passphrases (e.g. with your boy friend or your wife). The advantage
is that you can change the passphrase from time to time and decrease
the risk, that many old messages may be decrypted by people who
accidently got your passphrase.
You can add and copy keys to and from your keyring with the 'gpg
--import' and 'gpg --export' option. 'gpg --export-secret-keys' will
export secret keys. This is normally not useful, but you can generate
the key on one machine then move it to another machine.
Keys can be signed under the 'gpg --edit-key' option. When you sign a
key, you are saying that you are certain that the key belongs to the
person it says it comes from. You should be very sure that is really
that person: You should verify the key fingerprint
[H pre]
gpg --fingerprint user-id
[H/pre]
over phone (if you really know the voice of the other person) or at a
key signing party (which are often held at computer conferences) or at
a meeting of your local GNU/Linux User Group.
Hmm, what else. You may use the option "-o filename" to force output
to this filename (use "-" to force output to stdout). "-r" just lets
you specify the recipient (which public key you encrypt with) on the
command line instead of typing it interactively.
Oh yeah, this is important. By default all data is encrypted in some
weird binary format. If you want to have things appear in ASCII text
that is readable, just add the '-a' option. But the preferred method
is to use a MIME aware mail reader (Mutt, Pine and many more).
There is a small security glitch in the OpenPGP (and therefore GnuPG)
system; to avoid this you should always sign and encrypt a message
instead of only encrypting it.
<Q> Why are some signatures with an ELG-E key valid?
These are ElGamal Key generated by GnuPG in v3 (rfc1991) packets.
The OpenPGP draft later changed the algorithm identifier for ElGamal
keys which are usable for signatures and encryption from 16 to 20.
GnuPG now uses 20 when it generates new ElGamal keys but still
accept 16 (which is according to OpenPGP "encryption only") if this
key is in a v3 packet. GnuPG is the only program which had used
these v3 ElGamal keys - so this assumption is quite safe.
<Q> How does the whole trust thing work?
It works more or less like PGP. The difference is that the trust is
computed at the time it is needed. This is one of the reasons for
the trustdb which holds a list of valid key signatures. If you are
not running in batch mode you will be asked to assign a trust
parameter (ownertrust) to a key.
You can see the validity (calculated trust value) using this
command.
[H pre] gpg --list-keys --with-colons [H/pre]
If the first field is "pub" or "uid", the second field shows you the
trust:
[H pre]
o = Unknown (this key is new to the system)
e = The key has expired
q = Undefined (no value assigned)
n = Don't trust this key at all
m = There is marginal trust in this key
f = The key is full trusted
u = The key is ultimately trusted; this is only used
for keys for which the secret key is also available.
r = The key has been revoked
d = The key has been disabled
[H/pre]
The value in the "pub" record is the best one of all "uid" records.
You can get a list of the assigned trust values (how much you trust
the owner to correctly sign another person's key)
[H pre] gpg --list-ownertrust [H/pre] The first field is the
fingerprint of the primary key, the second field is the assigned
value:
[H pre]
- = No Ownertrust value yet assigned.
n = Never trust this keyholder to correctly verify others signatures.
m = Have marginal trust in the keyholders capability to sign other
keys.
f = Assume that the key holder really knows how to sign keys.
u = No need to trust ourself because we have the secret key.
[H/pre]
Keep these values confidential because they express your opinions
about others. PGP stores this information with the keyring thus it
is not a good idea to publish a PGP keyring instead of exporting the
keyring. gnupg stores the trust in the trust-DB so it is okay to
give a gpg keyring away (but we have a --export command too).
<Q> What kind of output is this: "key C26EE891.298, uid 09FB: ...."?
This is the internal representation of an user id in the trustdb.
"C26EE891" is the keyid, "298" is the local id (a record number in
the trustdb) and "09FB" is the last two bytes of a ripe-md-160 hash
of the user id for this key.
<Q> How do I interpret some of the informational outputs?
While checking the validity of a key, GnuPG sometimes prints some
information which is prefixed with information about the checked
item. [H pre] "key 12345678.3456" [H/pre] This is about the key
with key ID 12345678 and the internal number 3456, which is the
record number of the so called directory record in the trustdb.
[H pre] "uid 12345678.3456/ACDE" [H/pre] This is about the user ID for
the same key. To identify the user ID the last two bytes of a
ripe-md-160 over the user ID ring is printed. [H pre] "sig
12345678.3456/ACDE/9A8B7C6D" [H/pre] This is about the signature
with key ID 9A8B7C6D for the above key and user ID, if it is a
signature which is direct on a key, the user ID part is empty
(..//..).
<Q> Are the header lines of a cleartext signature part of the signed
material?
No. For example you can add or remove "Comment:" lines. They have
a purpose like the mail header lines. However a "Hash:" line is
needed for OpenPGP signatures to tell the parser which hash
algorithm to use.
<S> ACKNOWLEDGEMENTS
Many thanks to Werner Koch for the original FAQ file and to all
posters to gnupg-users and gnupg-devel. They all provided most of
the answers.
Also thanks to Casper Dik for providing me with a script to generate
this FAQ (he uses it for the excellent Solaris2 FAQ).
[H HR]
Copyright (C) 2000 Free Software Foundation, Inc. ,
59 Temple Place - Suite 330, Boston, MA 02111, USA
Verbatim copying and distribution of this entire article is permitted in
any medium, provided this notice is preserved.

14
g10/ChangeLog
View File

@ -1,3 +1,17 @@
Thu Sep 14 14:20:38 CEST 2000 Werner Koch <wk@openit.de>
* g10.c (main): Default S2K algorithms are now SHA1 and CAST5 - this
should solve a lot of compatibility problems with other OpenPGP
apps because those algorithms are SHOULD and not optional. The old
way to force it was by using the --openpgp option whith the drawback
that this would disable a couple of workarounds for PGP.
* g10.c (main): Don't set --quite along with --no-tty. By Frank Tobin.
* misc.c (disable_core_dump): Don't display a warning here but a return
a status value and ...
* g10.c (main): ...print warnining here. Suggested by Sam Roberts.
Wed Sep 13 18:12:34 CEST 2000 Werner Koch <wk@openit.de> Wed Sep 13 18:12:34 CEST 2000 Werner Koch <wk@openit.de>
* keyedit.c (keyedit_menu): Allow to use "debug" on the secret key. * keyedit.c (keyedit_menu): Allow to use "debug" on the secret key.

14
g10/g10.c
View File

@ -580,6 +580,7 @@ main( int argc, char **argv )
char **orig_argv; char **orig_argv;
const char *fname; const char *fname;
char *username; char *username;
int may_coredump;
STRLIST sl, remusr= NULL, locusr=NULL; STRLIST sl, remusr= NULL, locusr=NULL;
STRLIST nrings=NULL, sec_nrings=NULL; STRLIST nrings=NULL, sec_nrings=NULL;
armor_filter_context_t afx; armor_filter_context_t afx;
@ -613,7 +614,7 @@ main( int argc, char **argv )
*/ */
log_set_name("gpg"); log_set_name("gpg");
secure_random_alloc(); /* put random number into secure memory */ secure_random_alloc(); /* put random number into secure memory */
disable_core_dumps(); may_coredump = disable_core_dumps();
init_signals(); init_signals();
create_dotlock(NULL); /* register locking cleanup */ create_dotlock(NULL); /* register locking cleanup */
i18n_init(); i18n_init();
@ -624,8 +625,8 @@ main( int argc, char **argv )
opt.def_digest_algo = 0; opt.def_digest_algo = 0;
opt.def_compress_algo = 2; opt.def_compress_algo = 2;
opt.s2k_mode = 3; /* iterated+salted */ opt.s2k_mode = 3; /* iterated+salted */
opt.s2k_digest_algo = DIGEST_ALGO_RMD160; opt.s2k_digest_algo = DIGEST_ALGO_SHA1;
opt.s2k_cipher_algo = CIPHER_ALGO_BLOWFISH; opt.s2k_cipher_algo = CIPHER_ALGO_CAST5;
opt.completes_needed = 1; opt.completes_needed = 1;
opt.marginals_needed = 3; opt.marginals_needed = 3;
opt.max_cert_depth = 5; opt.max_cert_depth = 5;
@ -767,7 +768,7 @@ main( int argc, char **argv )
case oArmor: opt.armor = 1; opt.no_armor=0; break; case oArmor: opt.armor = 1; opt.no_armor=0; break;
case oOutput: opt.outfile = pargs.r.ret_str; break; case oOutput: opt.outfile = pargs.r.ret_str; break;
case oQuiet: opt.quiet = 1; break; case oQuiet: opt.quiet = 1; break;
case oNoTTY: opt.quiet = 1; tty_no_terminal(1); break; case oNoTTY: tty_no_terminal(1); break;
case oDryRun: opt.dry_run = 1; break; case oDryRun: opt.dry_run = 1; break;
case oInteractive: opt.interactive = 1; break; case oInteractive: opt.interactive = 1; break;
case oVerbose: g10_opt_verbose++; case oVerbose: g10_opt_verbose++;
@ -964,6 +965,11 @@ main( int argc, char **argv )
log_info("used in a production environment or with production keys!\n"); log_info("used in a production environment or with production keys!\n");
} }
#endif #endif
if( may_coredump && !opt.quiet )
log_info(_("WARNING: program may create a core file!\n"));
if (opt.no_literal) { if (opt.no_literal) {
log_info(_("NOTE: %s is not for normal use!\n"), "--no-literal"); log_info(_("NOTE: %s is not for normal use!\n"), "--no-literal");
if (opt.textmode) if (opt.textmode)

2
g10/main.h
View File

@ -54,7 +54,7 @@ char *make_radix64_string( const byte *data, size_t len );
/*-- misc.c --*/ /*-- misc.c --*/
void trap_unaligned(void); void trap_unaligned(void);
void disable_core_dumps(void); int disable_core_dumps(void);
u16 checksum_u16( unsigned n ); u16 checksum_u16( unsigned n );
u16 checksum( byte *p, unsigned n ); u16 checksum( byte *p, unsigned n );
u16 checksum_mpi( MPI a ); u16 checksum_mpi( MPI a );

13
g10/misc.c
View File

@ -79,22 +79,23 @@ trap_unaligned(void)
#endif #endif
void int
disable_core_dumps() disable_core_dumps()
{ {
#ifndef HAVE_DOSISH_SYSTEM #ifdef HAVE_DOSISH_SYSTEM
return 0;
#else
#ifdef HAVE_SETRLIMIT #ifdef HAVE_SETRLIMIT
struct rlimit limit; struct rlimit limit;
limit.rlim_cur = 0; limit.rlim_cur = 0;
limit.rlim_max = 0; limit.rlim_max = 0;
if( !setrlimit( RLIMIT_CORE, &limit ) ) if( !setrlimit( RLIMIT_CORE, &limit ) )
return; return 0;
if( errno != EINVAL ) if( errno != EINVAL && errno != ENOSYS )
log_fatal(_("can't disable core dumps: %s\n"), strerror(errno) ); log_fatal(_("can't disable core dumps: %s\n"), strerror(errno) );
#endif #endif
if( !opt.quiet ) return 1;
log_info(_("WARNING: program may create a core file!\n"));
#endif #endif
} }

4
tools/ChangeLog
View File

@ -1,3 +1,7 @@
Thu Sep 14 14:20:38 CEST 2000 Werner Koch <wk@openit.de>
* ring-a-party: Flush the last key.
Wed Jul 5 13:28:45 CEST 2000 Werner Koch <wk@> Wed Jul 5 13:28:45 CEST 2000 Werner Koch <wk@>
* mail-signed-keys: New. * mail-signed-keys: New.

3
tools/ring-a-party
View File

@ -31,6 +31,9 @@ BEGIN { FS=":"
page = 0; page = 0;
now = strftime("%b %d %H:%M %Y"); now = strftime("%b %d %H:%M %Y");
} }
END {
if (any) myflush();
}
$1 == "pub" { $1 == "pub" {
if( any ) myflush(); if( any ) myflush();
uidcount = 0; uidcount = 0;

5
util/ChangeLog
View File

@ -1,3 +1,8 @@
Thu Sep 14 14:20:38 CEST 2000 Werner Koch <wk@openit.de>
* miscutil.c (answer_is_yes_no_quit): Swapped order of yes/no test
so that no is returned for an empty input. By David Champion.
Wed Sep 6 17:55:47 CEST 2000 Werner Koch <wk@openit.de> Wed Sep 6 17:55:47 CEST 2000 Werner Koch <wk@openit.de>
* iobuf.c: Use fopen64 insead of fopen when available. * iobuf.c: Use fopen64 insead of fopen when available.

8
util/miscutil.c
View File

@ -310,16 +310,16 @@ answer_is_yes_no_quit( const char *s )
char *short_no = _("nN"); char *short_no = _("nN");
char *short_quit = _("qQ"); char *short_quit = _("qQ");
if( !stricmp(s, long_yes ) )
return 1;
if( !stricmp(s, long_no ) ) if( !stricmp(s, long_no ) )
return 0; return 0;
if( !stricmp(s, long_yes ) )
return 1;
if( !stricmp(s, long_quit ) ) if( !stricmp(s, long_quit ) )
return -1; return -1;
if( strchr( short_yes, *s ) && !s[1] )
return 1;
if( strchr( short_no, *s ) && !s[1] ) if( strchr( short_no, *s ) && !s[1] )
return 0; return 0;
if( strchr( short_yes, *s ) && !s[1] )
return 1;
if( strchr( short_quit, *s ) && !s[1] ) if( strchr( short_quit, *s ) && !s[1] )
return -1; return -1;
if( !stricmp(s, "yes" ) ) if( !stricmp(s, "yes" ) )