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authorNikos Mavrogiannopoulos <nmav@gnutls.org>2013-09-30 16:14:16 +0200
committerNikos Mavrogiannopoulos <nmav@gnutls.org>2013-09-30 16:14:16 +0200
commitf27d6be073c761463f01065733551dd498557820 (patch)
tree382cdedcb1673eac9016c0a7ab041f0bd65f3ef3 /doc
parentce89375245528eaf4a7b0e7d7d5bea7f08329150 (diff)
downloadgnutls-f27d6be073c761463f01065733551dd498557820.tar.gz
doc update
Diffstat (limited to 'doc')
-rw-r--r--doc/cha-tokens.texi21
1 files changed, 12 insertions, 9 deletions
diff --git a/doc/cha-tokens.texi b/doc/cha-tokens.texi
index 09be6e5d20..f88a767dac 100644
--- a/doc/cha-tokens.texi
+++ b/doc/cha-tokens.texi
@@ -369,18 +369,21 @@ certificates by specifying a PKCS #11 URL instead of a filename.
In this section we present the Trusted Platform Module (TPM) support
in @acronym{GnuTLS}. Note that this functionality is disabled by default
-because the @code{trousers} libraries GnuTLS depends on for that functionality
-are under the Common Public License which is not compatible with the GPL license.
+because the @code{trousers} libraries GnuTLS depends on
+are under the Common Public License which is not compatible with the GPL
+license. By disabling this feature by default we ensure that the GnuTLS library can
+be linked by both GPL and non-GPL programs, but you can enable this option
+during the library configuration.
There was a big hype when the TPM chip was introduced into
computers. Briefly it is a co-processor in your PC that allows it to perform
calculations independently of the main processor. This has good and bad
-side-effects. In this section we focus on the good ones, which are the fact that
-you can use it to perform cryptographic operations the similarly to a
-@acronym{PKCS} #11 smart card.
-It allows for storing and using RSA keys but with slight differences
-from a @acronym{PKCS} #11 module that require different handling.
-The basic operations supported, and used by GnuTLS, are key generation and signing.
+side-effects. In this section we focus on the good ones; these are the fact that
+you can use the TPM chip to perform cryptographic operations on keys stored in it, without
+accessing them. That is very similar to the operation of a @acronym{PKCS} #11 smart card.
+The chip allows for storage and usage of RSA keys, but has quite some
+operational differences from @acronym{PKCS} #11 module, and thus require different handling.
+The basic TPM operations supported and used by GnuTLS, are key generation and signing.
In GnuTLS the TPM functionality is available in @code{gnutls/tpm.h}.
@@ -397,7 +400,7 @@ In GnuTLS the TPM functionality is available in @code{gnutls/tpm.h}.
The RSA keys in the TPM module may either be stored in a flash memory
within TPM or stored in a file in disk. In the former case the key can
provide operations as with @acronym{PKCS} #11 and is identified by
-a URL. The URL is described in @xcite{TPMURI} and are of the following form.
+a URL. The URL is described in @xcite{TPMURI} and is of the following form.
@verbatim
tpmkey:uuid=42309df8-d101-11e1-a89a-97bb33c23ad1;storage=user
@end verbatim