--- /dev/null
+/*
+
+The MIT License (MIT)
+
+Copyright (c) 2016 Wrymouth Innovation Ltd
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included
+in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.
+
+*/
+
+#include <sys/types.h>
+
+#include "buffer.h"
+
+typedef struct buffer
+{
+ char *buf;
+ ssize_t size;
+ ssize_t hwm;
+ ssize_t ridx;
+ ssize_t widx;
+ int empty;
+} buffer_t;
+
+/* the buffer is organised internally as follows:
+ *
+ * * There are b->size bytes in the buffer.
+ *
+ * * Bytes are at offsets 0 to b->size-1
+ *
+ * * b->ridx points to the first readable byte
+ *
+ * * b->widx points to the first empty space
+ *
+ * * b->ridx < b->widx indicates a non-wrapped buffer:
+ *
+ * 0 ridx widx size
+ * | | | |
+ * V V V V
+ * ........XXXXXXXXX................
+ *
+ * * b->ridx > b->widx indicates a wrapped buffer:
+ *
+ * 0 widx ridx size
+ * | | | |
+ * V V V V
+ * XXXXXXXX.........XXXXXXXXXXXXXXXX
+ *
+ * * b->ridx == b->widx indicates a FULL buffer:
+ *
+ * * b->ridx == b->widx indicates a wrapped buffer:
+ *
+ * 0 widx == ridx size
+ * | | |
+ * V V V
+ * XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
+ *
+ * An empty buffer is indicated by empty=1
+ *
+ */
+
+buffer_t *
+bufNew (ssize_t size, ssize_t hwm)
+{
+ buffer_t *b = calloc (1, sizeof (buffer_t));
+ b->buf = calloc (1, size);
+ b->size = size;
+ b->hwm = hwm;
+ b->empty = 1;
+ return b;
+}
+
+
+void
+bufFree (buffer_t * b)
+{
+ free (b->buf);
+ free (b);
+}
+
+/* get a maximal span to read. Returns 0 if buffer
+ * is empty
+ */
+ssize_t
+bufGetReadSpan (buffer_t * b, void **addr)
+{
+ if (b->empty)
+ {
+ *addr = NULL;
+ return 0;
+ }
+ *addr = &(b->buf[b->ridx]);
+ ssize_t len = b->widx - b->ridx;
+ if (len <= 0)
+ len = b->size - b->ridx;
+ return len;
+}
+
+/* get a maximal span to write. Returns 0 id buffer is full
+ */
+ssize_t
+bufGetWriteSpan (buffer_t * b, void **addr)
+{
+ if (b->empty)
+ {
+ *addr = b->buf;
+ b->ridx = 0;
+ b->widx = 0;
+ return b->size;
+ }
+ if (b->ridx == b->widx)
+ {
+ *addr = NULL;
+ return 0;
+ }
+ *addr = &(b->buf[b->widx]);
+ ssize_t len = b->ridx - b->widx;
+ if (len <= 0)
+ len = b->size - b->widx;
+ return len;
+}
+
+/* mark size bytes as read */
+void
+bufDoneRead (buffer_t * b, ssize_t size)
+{
+ while (!b->empty && (size > 0))
+ {
+ /* empty can't occur here, so equal pointers means full */
+ ssize_t len = b->widx - b->ridx;
+ if (len <= 0)
+ len = b->size - b->ridx;
+
+ /* len is the number of bytes in one read span */
+ if (len > size)
+ len = size;
+
+ b->ridx += len;
+ if (b->ridx >= b->size)
+ b->ridx = 0;
+
+ if (b->ridx == b->widx)
+ {
+ b->ridx = 0;
+ b->widx = 0;
+ b->empty = 1;
+ }
+
+ size -= len;
+ }
+}
+
+/* mark size bytes as written */
+void
+bufDoneWrite (buffer_t * b, ssize_t size)
+{
+ while ((b->empty || (b->ridx != b->widx)) && (size > 0))
+ {
+ /* full can't occur here, so equal pointers means empty */
+ ssize_t len = b->ridx - b->widx;
+ if (len <= 0)
+ len = b->size - b->widx;
+
+ /* len is the number of bytes in one write span */
+ if (len > size)
+ len = size;
+
+ b->widx += len;
+ if (b->widx >= b->size)
+ b->widx = 0;
+
+ /* it can't be empty as we've written at least one byte */
+ b->empty = 0;
+
+ size -= len;
+ }
+}
+
+int
+bufIsEmpty (buffer_t * b)
+{
+ return b->empty;
+}
+
+int
+bufIsFull (buffer_t * b)
+{
+ return !b->empty && (b->ridx == b->widx);
+}
+
+int
+bufIsOverHWM (buffer_t * b)
+{
+ return bufGetCount (b) > b->hwm;
+}
+
+ssize_t
+bufGetFree (buffer_t * b)
+{
+ return b->size - bufGetCount (b);
+}
+
+ssize_t
+bufGetCount (buffer_t * b)
+{
+ if (b->empty)
+ return 0;
+ return b->widx - b->ridx + ((b->ridx < b->widx) ? 0 : b->size);
+}
--- /dev/null
+/*
+
+The MIT License (MIT)
+
+Copyright (c) 2016 Wrymouth Innovation Ltd
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included
+in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.
+
+*/
+
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <string.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/select.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <gnutls/gnutls.h>
+#include <gnutls/crypto.h>
+#include <gnutls/x509.h>
+#include <gnutls/abstract.h>
+
+#include "crypto-gnutls.h"
+#include "buffer.h"
+
+#define MAX_CERTS 10
+
+#define FALSE 0
+#define TRUE 1
+
+#define PRIORITY "NORMAL:-VERS-TLS-ALL:+VERS-TLS1.2"
+
+typedef struct tlssession
+{
+ gnutls_certificate_credentials_t creds;
+ gnutls_session_t session;
+ char *hostname;
+ int (*quitfn) (void *opaque);
+ int (*erroutfn) (void *opaque, const char *format, va_list ap);
+ int debug;
+ void *opaque;
+} tlssession_t;
+
+#define BUF_SIZE 65536
+#define BUF_HWM ((BUF_SIZE*3)/4)
+
+static int
+falsequit (void *opaque)
+{
+ return FALSE;
+}
+
+static int
+quit (tlssession_t * s)
+{
+ return s->quitfn (s->opaque);
+}
+
+
+static int
+stderrout (void *opaque, const char *format, va_list ap)
+{
+ return vfprintf (stderr, format, ap);
+}
+
+static int
+errout (tlssession_t * s, const char *format, ...)
+{
+ va_list ap;
+ int ret;
+ va_start (ap, format);
+ ret = s->erroutfn (s->opaque, format, ap);
+ va_end (ap);
+ return ret;
+}
+
+static int
+debugout (tlssession_t * s, const char *format, ...)
+{
+ va_list ap;
+ int ret = 0;
+ va_start (ap, format);
+ if (s->debug)
+ ret = s->erroutfn (s->opaque, format, ap);
+ va_end (ap);
+ return ret;
+}
+
+static int
+socksetnonblock (int fd, int nb)
+{
+ int sf = fcntl (fd, F_GETFL, 0);
+ if (sf == -1)
+ return -1;
+ return fcntl (fd, F_SETFL, nb ? (sf | O_NONBLOCK) : (sf & ~O_NONBLOCK));
+}
+
+/* From (public domain) example file in GNUTLS
+ *
+ * This function will try to verify the peer's certificate, and
+ * also check if the hostname matches, and the activation, expiration dates.
+ */
+static int
+verify_certificate_callback (gnutls_session_t session)
+{
+ unsigned int status;
+ const gnutls_datum_t *cert_list;
+ unsigned int cert_list_size;
+ int ret;
+ gnutls_x509_crt_t cert;
+ tlssession_t *s;
+
+ /* read session pointer */
+ s = (tlssession_t *) gnutls_session_get_ptr (session);
+
+ /* This verification function uses the trusted CAs in the credentials
+ * structure. So you must have installed one or more CA certificates.
+ */
+ ret = gnutls_certificate_verify_peers2 (session, &status);
+ if (ret < 0)
+ {
+ debugout (s, "Could not verfify peer certificate due to an error\n");
+ return GNUTLS_E_CERTIFICATE_ERROR;
+ }
+
+ if (status & GNUTLS_CERT_INVALID)
+ debugout (s, "The certificate is not trusted.\n");
+
+ if (status & GNUTLS_CERT_SIGNER_NOT_FOUND)
+ debugout (s, "The certificate hasn't got a known issuer.\n");
+
+ if (status & GNUTLS_CERT_REVOKED)
+ debugout (s, "The certificate has been revoked.\n");
+
+ if (status & GNUTLS_CERT_EXPIRED)
+ debugout (s, "The certificate has expired\n");
+
+ if (status & GNUTLS_CERT_NOT_ACTIVATED)
+ debugout (s, "The certificate is not yet activated\n");
+
+ if (status)
+ return GNUTLS_E_CERTIFICATE_ERROR;
+
+ if (gnutls_certificate_type_get (session) != GNUTLS_CRT_X509)
+ return GNUTLS_E_CERTIFICATE_ERROR;
+
+ if (gnutls_x509_crt_init (&cert) < 0)
+ {
+ debugout (s, "error in initialization\n");
+ return GNUTLS_E_CERTIFICATE_ERROR;
+ }
+
+ cert_list = gnutls_certificate_get_peers (session, &cert_list_size);
+ if (cert_list == NULL)
+ {
+ debugout (s, "No certificate was found!\n");
+ return GNUTLS_E_CERTIFICATE_ERROR;
+ }
+
+ /* check only the first certificate - seems to be what curl does */
+ if (gnutls_x509_crt_import (cert, &cert_list[0], GNUTLS_X509_FMT_DER) < 0)
+ {
+ debugout (s, "error parsing certificate\n");
+ return GNUTLS_E_CERTIFICATE_ERROR;
+ }
+
+ if (s->hostname && *s->hostname)
+ {
+ if (!gnutls_x509_crt_check_hostname (cert, s->hostname))
+ {
+ debugout (s,
+ "The certificate's owner does not match hostname '%s'\n",
+ s->hostname);
+ return GNUTLS_E_CERTIFICATE_ERROR;
+ }
+ }
+
+ gnutls_x509_crt_deinit (cert);
+
+ debugout (s, "Peer passed certificate verification\n");
+
+ /* notify gnutls to continue handshake normally */
+ return 0;
+}
+
+tlssession_t *
+tlssession_new (int isserver,
+ char *keyfile, char *certfile, char *cacertfile,
+ char *hostname, int insecure, int debug,
+ int (*quitfn) (void *opaque),
+ int (*erroutfn) (void *opaque, const char *format,
+ va_list ap), void *opaque)
+{
+ int ret;
+ tlssession_t *s = calloc (1, sizeof (tlssession_t));
+
+ if (quitfn)
+ s->quitfn = quitfn;
+ else
+ s->quitfn = falsequit;
+
+ if (erroutfn)
+ s->erroutfn = erroutfn;
+ else
+ s->erroutfn = stderrout;
+
+ if (hostname)
+ s->hostname = strdup (hostname);
+
+ s->debug = debug;
+
+ if (gnutls_certificate_allocate_credentials (&s->creds) < 0)
+ {
+ errout (s, "Certificate allocation memory error\n");
+ goto error;
+ }
+
+ if (cacertfile != NULL)
+ {
+ ret =
+ gnutls_certificate_set_x509_trust_file (s->creds, cacertfile,
+ GNUTLS_X509_FMT_PEM);
+ if (ret < 0)
+ {
+ errout (s, "Error setting the x509 trust file: %s\n",
+ gnutls_strerror (ret));
+ goto error;
+ }
+
+ if (!insecure)
+ {
+ gnutls_certificate_set_verify_function (s->creds,
+ verify_certificate_callback);
+ gnutls_certificate_set_verify_flags (s->creds,
+ GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT);
+ }
+ }
+
+ if (keyfile && !certfile)
+ certfile = keyfile;
+
+ if (certfile != NULL && keyfile != NULL)
+ {
+ ret =
+ gnutls_certificate_set_x509_key_file (s->creds, certfile, keyfile,
+ GNUTLS_X509_FMT_PEM);
+
+ if (ret < 0)
+ {
+ errout (s,
+ "Error loading certificate or key file (%s, %s): %s\n",
+ certfile, keyfile, gnutls_strerror (ret));
+ goto error;
+ }
+ }
+
+ if (isserver)
+ {
+ ret = gnutls_init (&s->session, GNUTLS_SERVER);
+ }
+ else
+ {
+ ret = gnutls_init (&s->session, GNUTLS_CLIENT);
+ }
+ if (ret < 0)
+ {
+ errout (s, "Cannot initialize GNUTLS session: %s\n",
+ gnutls_strerror (ret));
+ goto error;
+ }
+
+ gnutls_session_set_ptr (s->session, (void *) s);
+
+ ret = gnutls_set_default_priority (s->session);
+ if (ret < 0)
+ {
+ errout (s, "Cannot set default GNUTLS session priority: %s\n",
+ gnutls_strerror (ret));
+ goto error;
+ }
+
+ const char *errpos = NULL;
+ ret = gnutls_priority_set_direct(s->session, PRIORITY, &errpos);
+ if (ret < 0)
+ {
+ errout (s, "Cannot set GNUTLS session priority: %s\n",
+ gnutls_strerror (ret));
+ goto error;
+ }
+
+ gnutls_session_set_ptr (s->session, (void *) s);
+
+ ret = gnutls_credentials_set (s->session, GNUTLS_CRD_CERTIFICATE, s->creds);
+ if (ret < 0)
+ {
+ errout (s, "Cannot set session GNUTL credentials: %s\n",
+ gnutls_strerror (ret));
+ goto error;
+ }
+
+ if (isserver)
+ {
+ /* requests but does not check a client certificate */
+ gnutls_certificate_server_set_request (s->session, GNUTLS_CERT_REQUEST);
+ }
+
+
+ return s;
+
+error:
+ if (s->session)
+ gnutls_deinit (s->session);
+ free (s);
+ return NULL;
+}
+
+void
+tlssession_close (tlssession_t * s)
+{
+ if (s->session)
+ gnutls_deinit (s->session);
+ free (s->hostname);
+ free (s);
+}
+
+int
+tlssession_init ()
+{
+ return gnutls_global_init ();
+}
+
+
+int
+tlssession_mainloop (int cryptfd, int plainfd, tlssession_t * s)
+{
+ fd_set readfds;
+ fd_set writefds;
+ int maxfd;
+ int tls_wr_interrupted = 0;
+ int plainEOF = FALSE;
+ int cryptEOF = FALSE;
+ int ret;
+
+ buffer_t *plainToCrypt = bufNew (BUF_SIZE, BUF_HWM);
+ buffer_t *cryptToPlain = bufNew (BUF_SIZE, BUF_HWM);
+
+ if (socksetnonblock (cryptfd, 0) < 0)
+ {
+ errout (s, "Could not turn on blocking: %m");
+ goto error;
+ }
+
+ /* set it up to work with our FD */
+ gnutls_transport_set_ptr (s->session,
+ (gnutls_transport_ptr_t) (intptr_t) cryptfd);
+
+
+ /* Now do the handshake */
+ ret = gnutls_handshake (s->session);
+ if (ret < 0)
+ {
+ errout (s, "TLS handshake failed: %s\n", gnutls_strerror (ret));
+ goto error;
+ }
+
+ if (socksetnonblock (cryptfd, 1) < 0)
+ {
+ errout (s, "Could not turn on non-blocking on crypt FD: %m");
+ goto error;
+ }
+
+ if (socksetnonblock (plainfd, 1) < 0)
+ {
+ errout (s, "Could not turn on non-blocking on plain FD: %m");
+ goto error;
+ }
+
+ maxfd = (plainfd > cryptfd) ? plainfd + 1 : cryptfd + 1;
+
+ while ((!plainEOF || !cryptEOF) && !quit (s))
+ {
+ struct timeval timeout;
+ int result;
+ int selecterrno;
+ int wait = TRUE;
+
+ FD_ZERO (&readfds);
+ FD_ZERO (&writefds);
+
+ size_t buffered = gnutls_record_check_pending (s->session);
+ if (buffered)
+ wait = FALSE; /* do not wait for select to return if we have buffered data */
+
+ if (plainEOF)
+ {
+ /* plain text end has closed, but me may still have
+ * data yet to write to the crypt end */
+ if (bufIsEmpty (plainToCrypt) && !tls_wr_interrupted)
+ {
+ cryptEOF = TRUE;
+ break;
+ }
+ }
+ else
+ {
+ if (!bufIsEmpty (cryptToPlain))
+ FD_SET (plainfd, &writefds);
+ if (!bufIsOverHWM (plainToCrypt))
+ FD_SET (plainfd, &readfds);
+ }
+
+ if (cryptEOF)
+ {
+ /* crypt end has closed, but me way still have data to
+ * write from the crypt buffer */
+ if (bufIsEmpty (cryptToPlain) && !buffered)
+ {
+ plainEOF = TRUE;
+ break;
+ }
+ }
+ else
+ {
+ if (!bufIsEmpty (plainToCrypt) || tls_wr_interrupted)
+ FD_SET (cryptfd, &writefds);
+ if (!bufIsOverHWM (cryptToPlain))
+ FD_SET (cryptfd, &readfds);
+ }
+
+ /* Repeat select whilst EINTR happens */
+ do
+ {
+ timeout.tv_sec = wait ? 1 : 0;
+ timeout.tv_usec = 0;
+ result = select (maxfd, &readfds, &writefds, NULL, &timeout);
+
+ selecterrno = errno;
+ }
+ while ((result == -1) && (selecterrno == EINTR) && !quit (s));
+ if (quit (s))
+ break;
+
+ if (FD_ISSET (plainfd, &readfds))
+ {
+ /* we can read at least one byte */
+ void *addr = NULL;
+ /* get a span of characters to write to the
+ * buffer. As the empty portion may wrap the end of the
+ * circular buffer this might not be all we could read.
+ */
+ ssize_t len = bufGetWriteSpan (plainToCrypt, &addr);
+ if (len > 0)
+ {
+ ssize_t ret;
+ do
+ {
+ ret = read (plainfd, addr, (size_t) len);
+ }
+ while ((ret < 0) && (errno == EINTR) && !quit (s));
+ if (quit (s))
+ break;
+ if (ret < 0)
+ {
+ errout (s, "Error on read from plain socket: %m\n");
+ goto error;
+ }
+ if (ret == 0)
+ {
+ plainEOF = TRUE;
+ }
+ else
+ {
+ bufDoneWrite (plainToCrypt, ret); /* mark ret bytes as written to the buffer */
+ }
+ }
+ }
+
+ if (FD_ISSET (plainfd, &writefds))
+ {
+ /* we can write at least one byte */
+ void *addr = NULL;
+ /* get a span of characters to read from the buffer
+ * as the full portion may wrap the end of the circular buffer
+ * this might not be all we have to write.
+ */
+ ssize_t len = bufGetReadSpan (cryptToPlain, &addr);
+ if (len > 0)
+ {
+ ssize_t ret;
+ do
+ {
+ ret = write (plainfd, addr, (size_t) len);
+ }
+ while ((ret < 0) && (errno == EINTR) && !quit (s));
+ if (quit (s))
+ break;
+ if (ret < 0)
+ {
+ errout (s, "Error on write to plain socket: %m\n");
+ goto error;
+ }
+ bufDoneRead (cryptToPlain, ret); /* mark ret bytes as read from the buffer */
+ }
+ }
+
+ if (FD_ISSET (cryptfd, &readfds) || buffered)
+ {
+ /* we can read at least one byte */
+ void *addr = NULL;
+ /* get a span of characters to write to the
+ * buffer. As the empty portion may wrap the end of the
+ * circular buffer this might not be all we could read.
+ */
+ ssize_t len = bufGetWriteSpan (cryptToPlain, &addr);
+ if (len > 0)
+ {
+ ssize_t ret;
+ do
+ {
+ ret = gnutls_record_recv (s->session, addr, (size_t) len);
+ }
+ while (ret == GNUTLS_E_INTERRUPTED && !quit (s));
+ /* do not loop on GNUTLS_E_AGAIN - this means we'd block so we'd loop for
+ * ever
+ */
+ if (quit (s))
+ break;
+ if (ret < 0 && ret != GNUTLS_E_AGAIN)
+ {
+ errout (s, "Error on read from crypt socket: %s\n",
+ gnutls_strerror (ret));
+ goto error;
+ }
+ if (ret == 0)
+ {
+ cryptEOF = TRUE;
+ }
+ else
+ {
+ bufDoneWrite (cryptToPlain, ret); /* mark ret bytes as written to the buffer */
+ }
+ }
+ }
+
+ if (FD_ISSET (cryptfd, &writefds))
+ {
+ /* we can write at least one byte */
+ void *addr = NULL;
+ /* get a span of characters to read from the buffer
+ * as the full portion may wrap the end of the circular buffer
+ * this might not be all we have to write.
+ */
+ ssize_t len = bufGetReadSpan (plainToCrypt, &addr);
+ if (len > 0)
+ {
+ ssize_t ret;
+ do
+ {
+ if (tls_wr_interrupted)
+ {
+ ret = gnutls_record_send (s->session, NULL, 0);
+ }
+ else
+ {
+ ret = gnutls_record_send (s->session, addr, len);
+ }
+ }
+ while (ret == GNUTLS_E_INTERRUPTED && !quit (s));
+ if (quit (s))
+ break;
+ if (ret == GNUTLS_E_AGAIN)
+ {
+ /* we need to call this again with NULL parameters
+ * as it blocked
+ */
+ tls_wr_interrupted = TRUE;
+ }
+ else if (ret < 0)
+ {
+ errout (s, "Error on write to crypto socket: %s\n",
+ gnutls_strerror (ret));
+ goto error;
+ }
+ bufDoneRead (plainToCrypt, ret); /* mark ret bytes as read from the buffer */
+ }
+ }
+ }
+
+ ret = 0;
+ goto freereturn;
+
+error:
+ ret = -1;
+
+freereturn:
+ gnutls_bye (s->session, GNUTLS_SHUT_RDWR);
+ shutdown (plainfd, SHUT_RDWR);
+ bufFree (plainToCrypt);
+ bufFree (cryptToPlain);
+ return ret;
+}