This is gnutls-guile.info, produced by makeinfo version 5.2 from
gnutls-guile.texi.

This manual is last updated 10 August 2014 for version 3.2.21 of GnuTLS.

Copyright (C) 2001-2012 Free Software Foundation, Inc.

     Permission is granted to copy, distribute and/or modify this
     document under the terms of the GNU Free Documentation License,
     Version 1.3 or any later version published by the Free Software
     Foundation; with no Invariant Sections, no Front-Cover Texts, and
     no Back-Cover Texts.  A copy of the license is included in the
     section entitled "GNU Free Documentation License".
INFO-DIR-SECTION Software libraries
START-INFO-DIR-ENTRY
* GnuTLS-Guile: (gnutls-guile).		GNU Transport Layer Security Library. Guile bindings.
END-INFO-DIR-ENTRY


File: gnutls-guile.info,  Node: Top,  Next: Preface,  Up: (dir)

GnuTLS-Guile
************

This manual is last updated 10 August 2014 for version 3.2.21 of GnuTLS.

Copyright (C) 2001-2012 Free Software Foundation, Inc.

     Permission is granted to copy, distribute and/or modify this
     document under the terms of the GNU Free Documentation License,
     Version 1.3 or any later version published by the Free Software
     Foundation; with no Invariant Sections, no Front-Cover Texts, and
     no Back-Cover Texts.  A copy of the license is included in the
     section entitled "GNU Free Documentation License".

* Menu:

* Preface::                     Preface.
* Guile Preparations::          Note on installation and environment.
* Guile API Conventions::       Naming conventions and other idiosyncrasies.
* Guile Examples::              Quick start.
* Guile Reference::             The Scheme GnuTLS programming interface.
* Copying Information::         Copying information.


File: gnutls-guile.info,  Node: Preface,  Next: Guile Preparations,  Prev: Top,  Up: Top

1 Preface
*********

This manual describes the GNU Guile (http://www.gnu.org/software/guile/)
Scheme programming interface to GnuTLS. The reader is assumed to have
basic knowledge of the protocol and library.  Details missing from this
chapter may be found in Function reference, of the C API reference.

At this stage, not all the C functions are available from Scheme, but a
large subset thereof is available.


File: gnutls-guile.info,  Node: Guile Preparations,  Next: Guile API Conventions,  Prev: Preface,  Up: Top

2 Guile Preparations
********************

The GnuTLS Guile bindings are available for both the 1.8 and 2.0 stable
series of Guile.

By default they are installed under the GnuTLS installation directory,
typically '/usr/local/share/guile/site/').  Normally Guile will not find
the module there without help.  You may experience something like this:

     $ guile
     guile> (use-modules (gnutls))
     <unnamed port>: no code for module (gnutls)
     guile>

There are two ways to solve this.  The first is to make sure that when
building GnuTLS, the Guile bindings will be installed in the same place
where Guile looks.  You may do this by using the '--with-guile-site-dir'
parameter as follows:

     $ ./configure --with-guile-site-dir=no

This will instruct GnuTLS to attempt to install the Guile bindings where
Guile will look for them.  It will use 'guile-config info pkgdatadir' to
learn the path to use.

If Guile was installed into '/usr', you may also install GnuTLS using
the same prefix:

     $ ./configure --prefix=/usr

If you want to specify the path to install the Guile bindings you can
also specify the path directly:

     $ ./configure --with-guile-site-dir=/opt/guile/share/guile/site

The second solution requires some more work but may be easier to use if
you do not have system administrator rights to your machine.  You need
to instruct Guile so that it finds the GnuTLS Guile bindings.  Either
use the 'GUILE_LOAD_PATH' environment variable as follows:

     $ GUILE_LOAD_PATH="/usr/local/share/guile/site:$GUILE_LOAD_PATH" guile
     guile> (use-modules (gnutls))
     guile>

Alternatively, you can modify Guile's '%load-path' variable (*note
Guile's run-time options: (guile)Build Config.).

At this point, you might get an error regarding 'libguile-gnutls-v-0'
similar to:

     gnutls.scm:361:1: In procedure dynamic-link in expression (load-extension "libguile-gnutls-v-0" "scm_init_gnutls"):
     gnutls.scm:361:1: file: "libguile-gnutls-v-0", message: "libguile-gnutls-v-0.so: cannot open shared object file: No such file or directory"

In this case, you will need to modify the run-time linker path, for
example as follows:

     $ LD_LIBRARY_PATH=/usr/local/lib GUILE_LOAD_PATH=/usr/local/share/guile/site guile
     guile> (use-modules (gnutls))
     guile>

To check that you got the intended GnuTLS library version, you may print
the version number of the loaded library as follows:

     $ guile
     guile> (use-modules (gnutls))
     guile> (gnutls-version)
     "3.2.21"
     guile>


File: gnutls-guile.info,  Node: Guile API Conventions,  Next: Guile Examples,  Prev: Guile Preparations,  Up: Top

3 Guile API Conventions
***********************

This chapter details the conventions used by Guile API, as well as
specificities of the mapping of the C API to Scheme.

* Menu:

* Enumerates and Constants::      Representation of C-side constants.
* Procedure Names::               Naming conventions.
* Representation of Binary Data:: Binary data buffers.
* Input and Output::              Input and output.
* Exception Handling::            Exceptions.


File: gnutls-guile.info,  Node: Enumerates and Constants,  Next: Procedure Names,  Up: Guile API Conventions

3.1 Enumerates and Constants
============================

Lots of enumerates and constants are used in the GnuTLS C API. For each
C enumerate type, a disjoint Scheme type is used--thus, enumerate values
and constants are not represented by Scheme symbols nor by integers.
This makes it impossible to use an enumerate value of the wrong type on
the Scheme side: such errors are automatically detected by
type-checking.

The enumerate values are bound to variables exported by the '(gnutls)'
module.  These variables are named according to the following
convention:

   * All variable names are lower-case; the underscore '_' character
     used in the C API is replaced by hyphen '-'.
   * All variable names are prepended by the name of the enumerate type
     and the slash '/' character.
   * In some cases, the variable name is made more explicit than the one
     of the C API, e.g., by avoid abbreviations.

Consider for instance this C-side enumerate:

     typedef enum
     {
       GNUTLS_CRD_CERTIFICATE = 1,
       GNUTLS_CRD_ANON,
       GNUTLS_CRD_SRP,
       GNUTLS_CRD_PSK
     } gnutls_credentials_type_t;

The corresponding Scheme values are bound to the following variables
exported by the '(gnutls)' module:

     credentials/certificate
     credentials/anonymous
     credentials/srp
     credentials/psk

Hopefully, most variable names can be deduced from this convention.

Scheme-side "enumerate" values can be compared using 'eq?' (*note
equality predicates: (guile)Equality.).  Consider the following example:

     (let ((session (make-session connection-end/client)))

       ;;
       ;; ...
       ;;

       ;; Check the ciphering algorithm currently used by SESSION.
       (if (eq? cipher/arcfour (session-cipher session))
           (format #t "We're using the ARCFOUR algorithm")))

In addition, all enumerate values can be converted to a human-readable
string, in a type-specific way.  For instance, '(cipher->string
cipher/arcfour)' yields '"ARCFOUR 128"', while '(key-usage->string
key-usage/digital-signature)' yields '"digital-signature"'.  Note that
these strings may not be sufficient for use in a user interface since
they are fairly concise and not internationalized.


File: gnutls-guile.info,  Node: Procedure Names,  Next: Representation of Binary Data,  Prev: Enumerates and Constants,  Up: Guile API Conventions

3.2 Procedure Names
===================

Unlike C functions in GnuTLS, the corresponding Scheme procedures are
named in a way that is close to natural English.  Abbreviations are also
avoided.  For instance, the Scheme procedure corresponding to
'gnutls_certificate_set_dh_params' is named
'set-certificate-credentials-dh-parameters!'.  The 'gnutls_' prefix is
always omitted from variable names since a similar effect can be
achieved using Guile's nifty binding renaming facilities, should it be
needed (*note (guile)Using Guile Modules::).

Often Scheme procedure names differ from C function names in a way that
makes it clearer what objects they operate on.  For example, the Scheme
procedure named 'set-session-transport-port!' corresponds to
'gnutls_transport_set_ptr', making it clear that this procedure applies
to session.


File: gnutls-guile.info,  Node: Representation of Binary Data,  Next: Input and Output,  Prev: Procedure Names,  Up: Guile API Conventions

3.3 Representation of Binary Data
=================================

Many procedures operate on binary data.  For instance,
'pkcs3-import-dh-parameters' expects binary data as input and,
similarly, procedures like 'pkcs1-export-rsa-parameters' return binary
data.

Binary data is represented on the Scheme side using SRFI-4 homogeneous
vectors (*note (guile)SRFI-4::).  Although any type of homogeneous
vector may be used, 'u8vector's (i.e., vectors of bytes) are highly
recommended.

As an example, generating and then exporting RSA parameters in the PEM
format can be done as follows:

     (let* ((rsa-params (make-rsa-parameters 1024))
            (raw-data
             (pkcs1-export-rsa-parameters rsa-params
                                          x509-certificate-format/pem)))
       (uniform-vector-write raw-data (open-output-file "some-file.pem")))

For an example of OpenPGP key import from a file, see *note Importing
OpenPGP Keys Guile Example::.


File: gnutls-guile.info,  Node: Input and Output,  Next: Exception Handling,  Prev: Representation of Binary Data,  Up: Guile API Conventions

3.4 Input and Output
====================

The underlying transport of a TLS session can be any Scheme input/output
port (*note (guile)Ports and File Descriptors::).  This has to be
specified using 'set-session-transport-port!'.

However, for better performance, a raw file descriptor can be specified,
using 'set-session-transport-fd!'.  For instance, if the transport layer
is a socket port over an OS-provided socket, you can use the
'port->fdes' or 'fileno' procedure to obtain the underlying file
descriptor and pass it to 'set-session-transport-fd!' (*note
'port->fdes' and 'fileno': (guile)Ports and File Descriptors.).  This
would work as follows:

     (let ((socket (socket PF_INET SOCK_STREAM 0))
           (session (make-session connection-end/client)))

       ;;
       ;; Establish a TCP connection...
       ;;

       ;; Use the file descriptor that underlies SOCKET.
       (set-session-transport-fd! session (fileno socket)))

Once a TLS session is established, data can be communicated through it
(i.e., _via_ the TLS record layer) using the port returned by
'session-record-port':

     (let ((session (make-session connection-end/client)))

       ;;
       ;; Initialize the various parameters of SESSION, set up
       ;; a network connection, etc...
       ;;

       (let ((i/o (session-record-port session)))
         (write "Hello peer!" i/o)
         (let ((greetings (read i/o)))

           ;; ...

           (bye session close-request/rdwr))))

A lower-level I/O API is provided by 'record-send' and 'record-receive!'
which take an SRFI-4 vector to represent the data sent or received.
While it might improve performance, it is much less convenient than the
above and should rarely be needed.


File: gnutls-guile.info,  Node: Exception Handling,  Prev: Input and Output,  Up: Guile API Conventions

3.5 Exception Handling
======================

GnuTLS errors are implemented as Scheme exceptions (*note exceptions in
Guile: (guile)Exceptions.).  Each time a GnuTLS function returns an
error, an exception with key 'gnutls-error' is raised.  The additional
arguments that are thrown include an error code and the name of the
GnuTLS procedure that raised the exception.  The error code is pretty
much like an enumerate value: it is one of the 'error/' variables
exported by the '(gnutls)' module (*note Enumerates and Constants::).
Exceptions can be turned into error messages using the 'error->string'
procedure.

The following examples illustrates how GnuTLS exceptions can be handled:

     (let ((session (make-session connection-end/server)))

       ;;
       ;; ...
       ;;

       (catch 'gnutls-error
         (lambda ()
           (handshake session))
         (lambda (key err function . currently-unused)
           (format (current-error-port)
                   "a GnuTLS error was raised by `~a': ~a~%"
                   function (error->string err)))))

Again, error values can be compared using 'eq?':

         ;; `gnutls-error' handler.
         (lambda (key err function . currently-unused)
           (if (eq? err error/fatal-alert-received)
               (format (current-error-port)
                       "a fatal alert was caught!~%")
               (format (current-error-port)
                       "something bad happened: ~a~%"
                       (error->string err))))

Note that the 'catch' handler is currently passed only 3 arguments but
future versions might provide it with additional arguments.  Thus, it
must be prepared to handle more than 3 arguments, as in this example.


File: gnutls-guile.info,  Node: Guile Examples,  Next: Guile Reference,  Prev: Guile API Conventions,  Up: Top

4 Guile Examples
****************

This chapter provides examples that illustrate common use cases.

* Menu:

* Anonymous Authentication Guile Example::    Simplest client and server.
* OpenPGP Authentication Guile Example::      Using OpenPGP-based authentication.
* Importing OpenPGP Keys Guile Example::      Importing keys from files.


File: gnutls-guile.info,  Node: Anonymous Authentication Guile Example,  Next: OpenPGP Authentication Guile Example,  Up: Guile Examples

4.1 Anonymous Authentication Guile Example
==========================================

"Anonymous authentication" is very easy to use.  No certificates are
needed by the communicating parties.  Yet, it allows them to benefit
from end-to-end encryption and integrity checks.

The client-side code would look like this (assuming SOME-SOCKET is bound
to an open socket port):

     ;; Client-side.

     (let ((client (make-session connection-end/client)))
       ;; Use the default settings.
       (set-session-default-priority! client)

       ;; Don't use certificate-based authentication.
       (set-session-certificate-type-priority! client '())

       ;; Request the "anonymous Diffie-Hellman" key exchange method.
       (set-session-kx-priority! client (list kx/anon-dh))

       ;; Specify the underlying socket.
       (set-session-transport-fd! client (fileno some-socket))

       ;; Create anonymous credentials.
       (set-session-credentials! client
                                 (make-anonymous-client-credentials))

       ;; Perform the TLS handshake with the server.
       (handshake client)

       ;; Send data over the TLS record layer.
       (write "hello, world!" (session-record-port client))

       ;; Terminate the TLS session.
       (bye client close-request/rdwr))

The corresponding server would look like this (again, assuming
SOME-SOCKET is bound to a socket port):

     ;; Server-side.

     (let ((server (make-session connection-end/server)))
       (set-session-default-priority! server)
       (set-session-certificate-type-priority! server '())
       (set-session-kx-priority! server (list kx/anon-dh))

       ;; Specify the underlying transport socket.
       (set-session-transport-fd! server (fileno some-socket))

       ;; Create anonymous credentials.
       (let ((cred (make-anonymous-server-credentials))
             (dh-params (make-dh-parameters 1024)))
         ;; Note: DH parameter generation can take some time.
         (set-anonymous-server-dh-parameters! cred dh-params)
         (set-session-credentials! server cred))

       ;; Perform the TLS handshake with the client.
       (handshake server)

       ;; Receive data over the TLS record layer.
       (let ((message (read (session-record-port server))))
         (format #t "received the following message: ~a~%"
                 message)

         (bye server close-request/rdwr)))

This is it!


File: gnutls-guile.info,  Node: OpenPGP Authentication Guile Example,  Next: Importing OpenPGP Keys Guile Example,  Prev: Anonymous Authentication Guile Example,  Up: Guile Examples

4.2 OpenPGP Authentication Guile Example
========================================

GnuTLS allows users to authenticate using OpenPGP certificates.  Using
OpenPGP-based authentication is not more complicated than using
anonymous authentication.  It requires a bit of extra work, though, to
import the OpenPGP public and private key of the client/server.  Key
import is omitted here and is left as an exercise to the reader (*note
Importing OpenPGP Keys Guile Example::).

Assuming SOME-SOCKET is bound to an open socket port and PUB and SEC are
bound to the client's OpenPGP public and secret key, respectively,
client-side code would look like this:

     ;; Client-side.

     (define %certs (list certificate-type/openpgp))

     (let ((client (make-session connection-end/client))
           (cred   (make-certificate-credentials)))
       (set-session-default-priority! client)

       ;; Choose OpenPGP certificates.
       (set-session-certificate-type-priority! client %certs)

       ;; Prepare appropriate client credentials.
       (set-certificate-credentials-openpgp-keys! cred pub sec)
       (set-session-credentials! client cred)

       ;; Specify the underlying transport socket.
       (set-session-transport-fd! client (fileno some-socket))

       (handshake client)
       (write "hello, world!" (session-record-port client))
       (bye client close-request/rdwr))

Similarly, server-side code would be along these lines:

     ;; Server-side.

     (define %certs (list certificate-type/openpgp))

     (let ((server (make-session connection-end/server))
           (rsa    (make-rsa-parameters 1024))
           (dh     (make-dh-parameters 1024)))
       (set-session-default-priority! server)

       ;; Choose OpenPGP certificates.
       (set-session-certificate-type-priority! server %certs)

       (let ((cred (make-certificate-credentials)))
         ;; Prepare credentials with RSA and Diffie-Hellman parameters.
         (set-certificate-credentials-dh-parameters! cred dh)
         (set-certificate-credentials-rsa-export-parameters! cred rsa)
         (set-certificate-credentials-openpgp-keys! cred pub sec)
         (set-session-credentials! server cred))

       (set-session-transport-fd! server (fileno some-socket))

       (handshake server)
       (let ((msg (read (session-record-port server))))
         (format #t "received: ~a~%" msg)

         (bye server close-request/rdwr)))

In practice, generating RSA parameters (and Diffie-Hellman parameters)
can time a long time.  Thus, you may want to generate them once and
store them in a file for future re-use (*note
'pkcs1-export-rsa-parameters' and 'pkcs1-import-rsa-parameters': Guile
Reference.).


File: gnutls-guile.info,  Node: Importing OpenPGP Keys Guile Example,  Prev: OpenPGP Authentication Guile Example,  Up: Guile Examples

4.3 Importing OpenPGP Keys Guile Example
========================================

The following example provides a simple way of importing "ASCII-armored"
OpenPGP keys from files, using the 'import-openpgp-certificate' and
'import-openpgp-private-key' procedures.

     (use-modules (srfi srfi-4)
                  (gnutls))

     (define (import-key-from-file import-proc file)
       ;; Import OpenPGP key from FILE using IMPORT-PROC.

       ;; Prepare a u8vector large enough to hold the raw
       ;; key contents.
       (let* ((size (stat:size (stat path)))
              (raw  (make-u8vector size)))

         ;; Fill in the u8vector with the contents of FILE.
         (uniform-vector-read! raw (open-input-file file))

         ;; Pass the u8vector to the import procedure.
         (import-proc raw openpgp-certificate-format/base64)))


     (define (import-public-key-from-file file)
       (import-key-from-file import-openpgp-certificate file))

     (define (import-private-key-from-file file)
       (import-key-from-file import-openpgp-private-key file))

The procedures 'import-public-key-from-file' and
'import-private-key-from-file' can be passed a file name.  They return
an OpenPGP public key and private key object, respectively (*note
OpenPGP key objects: Guile Reference.).


File: gnutls-guile.info,  Node: Guile Reference,  Next: Copying Information,  Prev: Guile Examples,  Up: Top

5 Guile Reference
*****************

This chapter lists the GnuTLS Scheme procedures exported by the
'(gnutls)' module (*note (guile)The Guile module system::).

 -- Scheme Procedure: set-log-level! level
     Enable GnuTLS logging up to LEVEL (an integer).

 -- Scheme Procedure: set-log-procedure! proc
     Use PROC (a two-argument procedure) as the global GnuTLS log
     procedure.

 -- Scheme Procedure: set-certificate-credentials-openpgp-keys! cred pub
          sec
     Use certificate PUB and secret key SEC in certificate credentials
     CRED.

 -- Scheme Procedure: openpgp-keyring-contains-key-id? keyring id
     Return '#f' if key ID ID is in KEYRING, '#f' otherwise.

 -- Scheme Procedure: import-openpgp-keyring data format
     Import DATA (a u8vector) according to FORMAT and return the
     imported keyring.

 -- Scheme Procedure: openpgp-certificate-usage key
     Return a list of values denoting the key usage of KEY.

 -- Scheme Procedure: openpgp-certificate-version key
     Return the version of the OpenPGP message format (RFC2440) honored
     by KEY.

 -- Scheme Procedure: openpgp-certificate-algorithm key
     Return two values: the certificate algorithm used by KEY and the
     number of bits used.

 -- Scheme Procedure: openpgp-certificate-names key
     Return the list of names for KEY.

 -- Scheme Procedure: openpgp-certificate-name key index
     Return the INDEXth name of KEY.

 -- Scheme Procedure: openpgp-certificate-fingerprint key
     Return a new u8vector denoting the fingerprint of KEY.

 -- Scheme Procedure: openpgp-certificate-fingerprint! key fpr
     Store in FPR (a u8vector) the fingerprint of KEY.  Return the
     number of bytes stored in FPR.

 -- Scheme Procedure: openpgp-certificate-id! key id
     Store the ID (an 8 byte sequence) of certificate KEY in ID (a
     u8vector).

 -- Scheme Procedure: openpgp-certificate-id key
     Return the ID (an 8-element u8vector) of certificate KEY.

 -- Scheme Procedure: import-openpgp-private-key data format [pass]
     Return a new OpenPGP private key object resulting from the import
     of DATA (a uniform array) according to FORMAT.  Optionally, a
     passphrase may be provided.

 -- Scheme Procedure: import-openpgp-certificate data format
     Return a new OpenPGP certificate object resulting from the import
     of DATA (a uniform array) according to FORMAT.

 -- Scheme Procedure: x509-certificate-subject-alternative-name cert
          index
     Return two values: the alternative name type for CERT (i.e., one of
     the 'x509-subject-alternative-name/' values) and the actual subject
     alternative name (a string) at INDEX.  Both values are '#f' if no
     alternative name is available at INDEX.

 -- Scheme Procedure: x509-certificate-subject-key-id cert
     Return the subject key ID (a u8vector) for CERT.

 -- Scheme Procedure: x509-certificate-authority-key-id cert
     Return the key ID (a u8vector) of the X.509 certificate authority
     of CERT.

 -- Scheme Procedure: x509-certificate-key-id cert
     Return a statistically unique ID (a u8vector) for CERT that depends
     on its public key parameters.  This is normally a 20-byte SHA-1
     hash.

 -- Scheme Procedure: x509-certificate-version cert
     Return the version of CERT.

 -- Scheme Procedure: x509-certificate-key-usage cert
     Return the key usage of CERT (i.e., a list of 'key-usage/' values),
     or the empty list if CERT does not contain such information.

 -- Scheme Procedure: x509-certificate-public-key-algorithm cert
     Return two values: the public key algorithm (i.e., one of the
     'pk-algorithm/' values) of CERT and the number of bits used.

 -- Scheme Procedure: x509-certificate-signature-algorithm cert
     Return the signature algorithm used by CERT (i.e., one of the
     'sign-algorithm/' values).

 -- Scheme Procedure: x509-certificate-matches-hostname? cert hostname
     Return true if CERT matches HOSTNAME, a string denoting a DNS host
     name.  This is the basic implementation of RFC 2818
     (http://tools.ietf.org/html/rfc2818) (aka.  HTTPS).

 -- Scheme Procedure: x509-certificate-issuer-dn-oid cert index
     Return the OID (a string) at INDEX from CERT's issuer DN. Return
     '#f' if no OID is available at INDEX.

 -- Scheme Procedure: x509-certificate-dn-oid cert index
     Return OID (a string) at INDEX from CERT.  Return '#f' if no OID is
     available at INDEX.

 -- Scheme Procedure: x509-certificate-issuer-dn cert
     Return the distinguished name (DN) of X.509 certificate CERT.

 -- Scheme Procedure: x509-certificate-dn cert
     Return the distinguished name (DN) of X.509 certificate CERT.  The
     form of the DN is as described in RFC 2253
     (http://tools.ietf.org/html/rfc2253).

 -- Scheme Procedure: pkcs8-import-x509-private-key data format [pass
          [encrypted]]
     Return a new X.509 private key object resulting from the import of
     DATA (a uniform array) according to FORMAT.  Optionally, if PASS is
     not '#f', it should be a string denoting a passphrase.  ENCRYPTED
     tells whether the private key is encrypted ('#t' by default).

 -- Scheme Procedure: import-x509-private-key data format
     Return a new X.509 private key object resulting from the import of
     DATA (a uniform array) according to FORMAT.

 -- Scheme Procedure: import-x509-certificate data format
     Return a new X.509 certificate object resulting from the import of
     DATA (a uniform array) according to FORMAT.

 -- Scheme Procedure: server-session-psk-username session
     Return the username associated with PSK server session SESSION.

 -- Scheme Procedure: set-psk-client-credentials! cred username key
          key-format
     Set the client credentials for CRED, a PSK client credentials
     object.

 -- Scheme Procedure: make-psk-client-credentials
     Return a new PSK client credentials object.

 -- Scheme Procedure: set-psk-server-credentials-file! cred file
     Use FILE as the password file for PSK server credentials CRED.

 -- Scheme Procedure: make-psk-server-credentials
     Return new PSK server credentials.

 -- Scheme Procedure: peer-certificate-status session
     Verify the peer certificate for SESSION and return a list of
     'certificate-status' values (such as 'certificate-status/revoked'),
     or the empty list if the certificate is valid.

 -- Scheme Procedure: set-certificate-credentials-verify-flags! cred
          [flags...]
     Set the certificate verification flags to FLAGS, a series of
     'certificate-verify' values.

 -- Scheme Procedure: set-certificate-credentials-verify-limits! cred
          max-bits max-depth
     Set the verification limits of 'peer-certificate-status' for
     certificate credentials CRED to MAX_BITS bits for an acceptable
     certificate and MAX_DEPTH as the maximum depth of a certificate
     chain.

 -- Scheme Procedure: set-certificate-credentials-x509-keys! cred certs
          privkey
     Have certificate credentials CRED use the X.509 certificates listed
     in CERTS and X.509 private key PRIVKEY.

 -- Scheme Procedure: set-certificate-credentials-x509-key-data! cred
          cert key format
     Use X.509 certificate CERT and private key KEY, both uniform arrays
     containing the X.509 certificate and key in format FORMAT, for
     certificate credentials CRED.

 -- Scheme Procedure: set-certificate-credentials-x509-crl-data! cred
          data format
     Use DATA (a uniform array) as the X.509 CRL (certificate revocation
     list) database for CRED.  On success, return the number of CRLs
     processed.

 -- Scheme Procedure: set-certificate-credentials-x509-trust-data! cred
          data format
     Use DATA (a uniform array) as the X.509 trust database for CRED.
     On success, return the number of certificates processed.

 -- Scheme Procedure: set-certificate-credentials-x509-crl-file! cred
          file format
     Use FILE as the X.509 CRL (certificate revocation list) file for
     certificate credentials CRED.  On success, return the number of
     CRLs processed.

 -- Scheme Procedure: set-certificate-credentials-x509-trust-file! cred
          file format
     Use FILE as the X.509 trust file for certificate credentials CRED.
     On success, return the number of certificates processed.

 -- Scheme Procedure: set-certificate-credentials-x509-key-files! cred
          cert-file key-file format
     Use FILE as the password file for PSK server credentials CRED.

 -- Scheme Procedure: set-certificate-credentials-rsa-export-parameters!
          cred rsa-params
     Use RSA parameters RSA_PARAMS for certificate credentials CRED.

 -- Scheme Procedure: set-certificate-credentials-dh-parameters! cred
          dh-params
     Use Diffie-Hellman parameters DH_PARAMS for certificate credentials
     CRED.

 -- Scheme Procedure: make-certificate-credentials
     Return new certificate credentials (i.e., for use with either X.509
     or OpenPGP certificates.

 -- Scheme Procedure: pkcs1-export-rsa-parameters rsa-params format
     Export Diffie-Hellman parameters RSA_PARAMS in PKCS1 format
     according for FORMAT (an 'x509-certificate-format' value).  Return
     a 'u8vector' containing the result.

 -- Scheme Procedure: pkcs1-import-rsa-parameters array format
     Import Diffie-Hellman parameters in PKCS1 format (further specified
     by FORMAT, an 'x509-certificate-format' value) from ARRAY (a
     homogeneous array) and return a new 'rsa-params' object.

 -- Scheme Procedure: make-rsa-parameters bits
     Return new RSA parameters.

 -- Scheme Procedure: set-anonymous-server-dh-parameters! cred dh-params
     Set the Diffie-Hellman parameters of anonymous server credentials
     CRED.

 -- Scheme Procedure: make-anonymous-client-credentials
     Return anonymous client credentials.

 -- Scheme Procedure: make-anonymous-server-credentials
     Return anonymous server credentials.

 -- Scheme Procedure: set-session-dh-prime-bits! session bits
     Use BITS DH prime bits for SESSION.

 -- Scheme Procedure: pkcs3-export-dh-parameters dh-params format
     Export Diffie-Hellman parameters DH_PARAMS in PKCS3 format
     according for FORMAT (an 'x509-certificate-format' value).  Return
     a 'u8vector' containing the result.

 -- Scheme Procedure: pkcs3-import-dh-parameters array format
     Import Diffie-Hellman parameters in PKCS3 format (further specified
     by FORMAT, an 'x509-certificate-format' value) from ARRAY (a
     homogeneous array) and return a new 'dh-params' object.

 -- Scheme Procedure: make-dh-parameters bits
     Return new Diffie-Hellman parameters.

 -- Scheme Procedure: set-session-transport-port! session port
     Use PORT as the input/output port for SESSION.

 -- Scheme Procedure: set-session-transport-fd! session fd
     Use file descriptor FD as the underlying transport for SESSION.

 -- Scheme Procedure: session-record-port session
     Return a read-write port that may be used to communicate over
     SESSION.  All invocations of 'session-port' on a given session
     return the same object (in the sense of 'eq?').

 -- Scheme Procedure: record-receive! session array
     Receive data from SESSION into ARRAY, a uniform homogeneous array.
     Return the number of bytes actually received.

 -- Scheme Procedure: record-send session array
     Send the record constituted by ARRAY through SESSION.

 -- Scheme Procedure: set-session-server-name! session type name
     For a client, this procedure provides a way to inform the server
     that it is known under NAME, via the 'SERVER NAME' TLS extension.
     TYPE must be a 'server-name-type' value, SERVER-NAME-TYPE/DNS for
     DNS names.

 -- Scheme Procedure: set-session-credentials! session cred
     Use CRED as SESSION's credentials.

 -- Scheme Procedure: cipher-suite->string kx cipher mac
     Return the name of the given cipher suite.

 -- Scheme Procedure: set-session-priorities! session priorities
     Have SESSION use the given PRIORITIES for the ciphers, key exchange
     methods, MACs and compression methods.  PRIORITIES must be a string
     (*note (gnutls)Priority Strings::).  When PRIORITIES cannot be
     parsed, an 'error/invalid-request' error is raised, with an extra
     argument indication the position of the error.

 -- Scheme Procedure: set-session-default-export-priority! session
     Have SESSION use the default export priorities.

 -- Scheme Procedure: set-session-default-priority! session
     Have SESSION use the default priorities.

 -- Scheme Procedure: set-session-certificate-type-priority! session
          items
     Use ITEMS (a list) as the list of preferred certificate-type for
     SESSION.

 -- Scheme Procedure: set-session-protocol-priority! session items
     Use ITEMS (a list) as the list of preferred protocol for SESSION.

 -- Scheme Procedure: set-session-kx-priority! session items
     Use ITEMS (a list) as the list of preferred kx for SESSION.

 -- Scheme Procedure: set-session-compression-method-priority! session
          items
     Use ITEMS (a list) as the list of preferred compression-method for
     SESSION.

 -- Scheme Procedure: set-session-mac-priority! session items
     Use ITEMS (a list) as the list of preferred mac for SESSION.

 -- Scheme Procedure: set-session-cipher-priority! session items
     Use ITEMS (a list) as the list of preferred cipher for SESSION.

 -- Scheme Procedure: set-server-session-certificate-request! session
          request
     Tell how SESSION, a server-side session, should deal with
     certificate requests.  REQUEST should be either
     'certificate-request/request' or 'certificate-request/require'.

 -- Scheme Procedure: session-our-certificate-chain session
     Return our certificate chain for SESSION (as sent to the peer) in
     raw format (a u8vector).  In the case of OpenPGP there is exactly
     one certificate.  Return the empty list if no certificate was used.

 -- Scheme Procedure: session-peer-certificate-chain session
     Return the a list of certificates in raw format (u8vectors) where
     the first one is the peer's certificate.  In the case of OpenPGP,
     there is always exactly one certificate.  In the case of X.509,
     subsequent certificates indicate form a certificate chain.  Return
     the empty list if no certificate was sent.

 -- Scheme Procedure: session-client-authentication-type session
     Return the client authentication type (a 'credential-type' value)
     used in SESSION.

 -- Scheme Procedure: session-server-authentication-type session
     Return the server authentication type (a 'credential-type' value)
     used in SESSION.

 -- Scheme Procedure: session-authentication-type session
     Return the authentication type (a 'credential-type' value) used by
     SESSION.

 -- Scheme Procedure: session-protocol session
     Return the protocol used by SESSION.

 -- Scheme Procedure: session-certificate-type session
     Return SESSION's certificate type.

 -- Scheme Procedure: session-compression-method session
     Return SESSION's compression method.

 -- Scheme Procedure: session-mac session
     Return SESSION's MAC.

 -- Scheme Procedure: session-kx session
     Return SESSION's kx.

 -- Scheme Procedure: session-cipher session
     Return SESSION's cipher.

 -- Scheme Procedure: alert-send session level alert
     Send ALERT via SESSION.

 -- Scheme Procedure: alert-get session
     Get an aleter from SESSION.

 -- Scheme Procedure: rehandshake session
     Perform a re-handshaking for SESSION.

 -- Scheme Procedure: handshake session
     Perform a handshake for SESSION.

 -- Scheme Procedure: bye session how
     Close SESSION according to HOW.

 -- Scheme Procedure: make-session end
     Return a new session for connection end END, either
     'connection-end/server' or 'connection-end/client'.

 -- Scheme Procedure: gnutls-version
     Return a string denoting the version number of the underlying
     GnuTLS library, e.g., '"1.7.2"'.

 -- Scheme Procedure: openpgp-keyring? obj
     Return true if OBJ is of type 'openpgp-keyring'.

 -- Scheme Procedure: openpgp-private-key? obj
     Return true if OBJ is of type 'openpgp-private-key'.

 -- Scheme Procedure: openpgp-certificate? obj
     Return true if OBJ is of type 'openpgp-certificate'.

 -- Scheme Procedure: x509-private-key? obj
     Return true if OBJ is of type 'x509-private-key'.

 -- Scheme Procedure: x509-certificate? obj
     Return true if OBJ is of type 'x509-certificate'.

 -- Scheme Procedure: psk-client-credentials? obj
     Return true if OBJ is of type 'psk-client-credentials'.

 -- Scheme Procedure: psk-server-credentials? obj
     Return true if OBJ is of type 'psk-server-credentials'.

 -- Scheme Procedure: srp-client-credentials? obj
     Return true if OBJ is of type 'srp-client-credentials'.

 -- Scheme Procedure: srp-server-credentials? obj
     Return true if OBJ is of type 'srp-server-credentials'.

 -- Scheme Procedure: certificate-credentials? obj
     Return true if OBJ is of type 'certificate-credentials'.

 -- Scheme Procedure: rsa-parameters? obj
     Return true if OBJ is of type 'rsa-parameters'.

 -- Scheme Procedure: dh-parameters? obj
     Return true if OBJ is of type 'dh-parameters'.

 -- Scheme Procedure: anonymous-server-credentials? obj
     Return true if OBJ is of type 'anonymous-server-credentials'.

 -- Scheme Procedure: anonymous-client-credentials? obj
     Return true if OBJ is of type 'anonymous-client-credentials'.

 -- Scheme Procedure: session? obj
     Return true if OBJ is of type 'session'.

 -- Scheme Procedure: openpgp-certificate-format->string enumval
     Return a string describing ENUMVAL, a 'openpgp-certificate-format'
     value.

 -- Scheme Procedure: error->string enumval
     Return a string describing ENUMVAL, a 'error' value.

 -- Scheme Procedure: certificate-verify->string enumval
     Return a string describing ENUMVAL, a 'certificate-verify' value.

 -- Scheme Procedure: key-usage->string enumval
     Return a string describing ENUMVAL, a 'key-usage' value.

 -- Scheme Procedure: psk-key-format->string enumval
     Return a string describing ENUMVAL, a 'psk-key-format' value.

 -- Scheme Procedure: server-name-type->string enumval
     Return a string describing ENUMVAL, a 'server-name-type' value.

 -- Scheme Procedure: sign-algorithm->string enumval
     Return a string describing ENUMVAL, a 'sign-algorithm' value.

 -- Scheme Procedure: pk-algorithm->string enumval
     Return a string describing ENUMVAL, a 'pk-algorithm' value.

 -- Scheme Procedure: x509-subject-alternative-name->string enumval
     Return a string describing ENUMVAL, a
     'x509-subject-alternative-name' value.

 -- Scheme Procedure: x509-certificate-format->string enumval
     Return a string describing ENUMVAL, a 'x509-certificate-format'
     value.

 -- Scheme Procedure: certificate-type->string enumval
     Return a string describing ENUMVAL, a 'certificate-type' value.

 -- Scheme Procedure: protocol->string enumval
     Return a string describing ENUMVAL, a 'protocol' value.

 -- Scheme Procedure: close-request->string enumval
     Return a string describing ENUMVAL, a 'close-request' value.

 -- Scheme Procedure: certificate-request->string enumval
     Return a string describing ENUMVAL, a 'certificate-request' value.

 -- Scheme Procedure: certificate-status->string enumval
     Return a string describing ENUMVAL, a 'certificate-status' value.

 -- Scheme Procedure: handshake-description->string enumval
     Return a string describing ENUMVAL, a 'handshake-description'
     value.

 -- Scheme Procedure: alert-description->string enumval
     Return a string describing ENUMVAL, a 'alert-description' value.

 -- Scheme Procedure: alert-level->string enumval
     Return a string describing ENUMVAL, a 'alert-level' value.

 -- Scheme Procedure: connection-end->string enumval
     Return a string describing ENUMVAL, a 'connection-end' value.

 -- Scheme Procedure: compression-method->string enumval
     Return a string describing ENUMVAL, a 'compression-method' value.

 -- Scheme Procedure: digest->string enumval
     Return a string describing ENUMVAL, a 'digest' value.

 -- Scheme Procedure: mac->string enumval
     Return a string describing ENUMVAL, a 'mac' value.

 -- Scheme Procedure: credentials->string enumval
     Return a string describing ENUMVAL, a 'credentials' value.

 -- Scheme Procedure: params->string enumval
     Return a string describing ENUMVAL, a 'params' value.

 -- Scheme Procedure: kx->string enumval
     Return a string describing ENUMVAL, a 'kx' value.

 -- Scheme Procedure: cipher->string enumval
     Return a string describing ENUMVAL, a 'cipher' value.


File: gnutls-guile.info,  Node: Copying Information,  Prev: Guile Reference,  Up: Top

Appendix A Copying Information
******************************

GNU Free Documentation License
==============================

                     Version 1.3, 3 November 2008

     Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
     <http://fsf.org/>

     Everyone is permitted to copy and distribute verbatim copies
     of this license document, but changing it is not allowed.

  0. PREAMBLE

     The purpose of this License is to make a manual, textbook, or other
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     assure everyone the effective freedom to copy and redistribute it,
     with or without modifying it, either commercially or
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     This License is a kind of "copyleft", which means that derivative
     works of the document must themselves be free in the same sense.
     It complements the GNU General Public License, which is a copyleft
     license designed for free software.

     We have designed this License in order to use it for manuals for
     free software, because free software needs free documentation: a
     free program should come with manuals providing the same freedoms
     that the software does.  But this License is not limited to
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     instruction or reference.

  1. APPLICABILITY AND DEFINITIONS

     This License applies to any manual or other work, in any medium,
     that contains a notice placed by the copyright holder saying it can
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     the license if you copy, modify or distribute the work in a way
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     A "Modified Version" of the Document means any work containing the
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  2. VERBATIM COPYING

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  4. MODIFICATIONS

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       O. Preserve any Warranty Disclaimers.

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  5. COMBINING DOCUMENTS

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     their Warranty Disclaimers.

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     In the combination, you must combine any sections Entitled
     "History" in the various original documents, forming one section
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     must delete all sections Entitled "Endorsements."

  6. COLLECTIONS OF DOCUMENTS

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     You may extract a single document from such a collection, and
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  7. AGGREGATION WITH INDEPENDENT WORKS

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  8. TRANSLATION

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     translations of some or all Invariant Sections in addition to the
     original versions of these Invariant Sections.  You may include a
     translation of this License, and all the license notices in the
     Document, and any Warranty Disclaimers, provided that you also
     include the original English version of this License and the
     original versions of those notices and disclaimers.  In case of a
     disagreement between the translation and the original version of
     this License or a notice or disclaimer, the original version will
     prevail.

     If a section in the Document is Entitled "Acknowledgements",
     "Dedications", or "History", the requirement (section 4) to
     Preserve its Title (section 1) will typically require changing the
     actual title.

  9. TERMINATION

     You may not copy, modify, sublicense, or distribute the Document
     except as expressly provided under this License.  Any attempt
     otherwise to copy, modify, sublicense, or distribute it is void,
     and will automatically terminate your rights under this License.

     However, if you cease all violation of this License, then your
     license from a particular copyright holder is reinstated (a)
     provisionally, unless and until the copyright holder explicitly and
     finally terminates your license, and (b) permanently, if the
     copyright holder fails to notify you of the violation by some
     reasonable means prior to 60 days after the cessation.

     Moreover, your license from a particular copyright holder is
     reinstated permanently if the copyright holder notifies you of the
     violation by some reasonable means, this is the first time you have
     received notice of violation of this License (for any work) from
     that copyright holder, and you cure the violation prior to 30 days
     after your receipt of the notice.

     Termination of your rights under this section does not terminate
     the licenses of parties who have received copies or rights from you
     under this License.  If your rights have been terminated and not
     permanently reinstated, receipt of a copy of some or all of the
     same material does not give you any rights to use it.

  10. FUTURE REVISIONS OF THIS LICENSE

     The Free Software Foundation may publish new, revised versions of
     the GNU Free Documentation License from time to time.  Such new
     versions will be similar in spirit to the present version, but may
     differ in detail to address new problems or concerns.  See
     <http://www.gnu.org/copyleft/>.

     Each version of the License is given a distinguishing version
     number.  If the Document specifies that a particular numbered
     version of this License "or any later version" applies to it, you
     have the option of following the terms and conditions either of
     that specified version or of any later version that has been
     published (not as a draft) by the Free Software Foundation.  If the
     Document does not specify a version number of this License, you may
     choose any version ever published (not as a draft) by the Free
     Software Foundation.  If the Document specifies that a proxy can
     decide which future versions of this License can be used, that
     proxy's public statement of acceptance of a version permanently
     authorizes you to choose that version for the Document.

  11. RELICENSING

     "Massive Multiauthor Collaboration Site" (or "MMC Site") means any
     World Wide Web server that publishes copyrightable works and also
     provides prominent facilities for anybody to edit those works.  A
     public wiki that anybody can edit is an example of such a server.
     A "Massive Multiauthor Collaboration" (or "MMC") contained in the
     site means any set of copyrightable works thus published on the MMC
     site.

     "CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0
     license published by Creative Commons Corporation, a not-for-profit
     corporation with a principal place of business in San Francisco,
     California, as well as future copyleft versions of that license
     published by that same organization.

     "Incorporate" means to publish or republish a Document, in whole or
     in part, as part of another Document.

     An MMC is "eligible for relicensing" if it is licensed under this
     License, and if all works that were first published under this
     License somewhere other than this MMC, and subsequently
     incorporated in whole or in part into the MMC, (1) had no cover
     texts or invariant sections, and (2) were thus incorporated prior
     to November 1, 2008.

     The operator of an MMC Site may republish an MMC contained in the
     site under CC-BY-SA on the same site at any time before August 1,
     2009, provided the MMC is eligible for relicensing.

ADDENDUM: How to use this License for your documents
====================================================

To use this License in a document you have written, include a copy of
the License in the document and put the following copyright and license
notices just after the title page:

       Copyright (C)  YEAR  YOUR NAME.
       Permission is granted to copy, distribute and/or modify this document
       under the terms of the GNU Free Documentation License, Version 1.3
       or any later version published by the Free Software Foundation;
       with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
       Texts.  A copy of the license is included in the section entitled ``GNU
       Free Documentation License''.

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts,
replace the "with...Texts." line with this:

         with the Invariant Sections being LIST THEIR TITLES, with
         the Front-Cover Texts being LIST, and with the Back-Cover Texts
         being LIST.

If you have Invariant Sections without Cover Texts, or some other
combination of the three, merge those two alternatives to suit the
situation.

If your document contains nontrivial examples of program code, we
recommend releasing these examples in parallel under your choice of free
software license, such as the GNU General Public License, to permit
their use in free software.



Tag Table:
Node: Top778
Node: Preface1771
Node: Guile Preparations2276
Node: Guile API Conventions4915
Node: Enumerates and Constants5489
Node: Procedure Names7814
Node: Representation of Binary Data8797
Node: Input and Output9904
Node: Exception Handling11777
Node: Guile Examples13605
Node: Anonymous Authentication Guile Example14059
Node: OpenPGP Authentication Guile Example16621
Node: Importing OpenPGP Keys Guile Example19503
Node: Guile Reference20943
Node: Copying Information41815

End Tag Table
