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-rw-r--r--openvpn/reliable.c700
1 files changed, 0 insertions, 700 deletions
diff --git a/openvpn/reliable.c b/openvpn/reliable.c
deleted file mode 100644
index ca83b2b..0000000
--- a/openvpn/reliable.c
+++ /dev/null
@@ -1,700 +0,0 @@
-/*
- * OpenVPN -- An application to securely tunnel IP networks
- * over a single UDP port, with support for SSL/TLS-based
- * session authentication and key exchange,
- * packet encryption, packet authentication, and
- * packet compression.
- *
- * Copyright (C) 2002-2005 OpenVPN Solutions LLC <info@openvpn.net>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2
- * as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program (see the file COPYING included with this
- * distribution); if not, write to the Free Software Foundation, Inc.,
- * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- */
-
-/*
- * These routines implement a reliability layer on top of UDP,
- * so that SSL/TLS can be run over UDP.
- */
-
-#ifdef WIN32
-#include "config-win32.h"
-#else
-#include "config.h"
-#endif
-
-#if defined(USE_CRYPTO) && defined(USE_SSL)
-
-#include "syshead.h"
-
-#include "buffer.h"
-#include "error.h"
-#include "common.h"
-#include "reliable.h"
-
-#include "memdbg.h"
-
-/* check if a particular packet_id is present in ack */
-static inline bool
-reliable_ack_packet_id_present (struct reliable_ack *ack, packet_id_type pid)
-{
- int i;
- for (i = 0; i < ack->len; ++i)
- if (ack->packet_id[i] == pid)
- return true;
- return false;
-}
-
-/* get a packet_id from buf */
-bool
-reliable_ack_read_packet_id (struct buffer *buf, packet_id_type *pid)
-{
- packet_id_type net_pid;
-
- if (buf_read (buf, &net_pid, sizeof (net_pid)))
- {
- *pid = ntohpid (net_pid);
- dmsg (D_REL_DEBUG, "ACK read ID " packet_id_format " (buf->len=%d)",
- (packet_id_print_type)*pid, buf->len);
- return true;
- }
-
- dmsg (D_REL_LOW, "ACK read ID FAILED (buf->len=%d)", buf->len);
- return false;
-}
-
-/* acknowledge a packet_id by adding it to a struct reliable_ack */
-bool
-reliable_ack_acknowledge_packet_id (struct reliable_ack *ack, packet_id_type pid)
-{
- if (!reliable_ack_packet_id_present (ack, pid) && ack->len < RELIABLE_ACK_SIZE)
- {
- ack->packet_id[ack->len++] = pid;
- dmsg (D_REL_DEBUG, "ACK acknowledge ID " packet_id_format " (ack->len=%d)",
- (packet_id_print_type)pid, ack->len);
- return true;
- }
-
- dmsg (D_REL_LOW, "ACK acknowledge ID " packet_id_format " FAILED (ack->len=%d)",
- (packet_id_print_type)pid, ack->len);
- return false;
-}
-
-/* read a packet ID acknowledgement record from buf into ack */
-bool
-reliable_ack_read (struct reliable_ack * ack,
- struct buffer * buf, const struct session_id * sid)
-{
- struct gc_arena gc = gc_new ();
- int i;
- uint8_t count;
- packet_id_type net_pid;
- packet_id_type pid;
- struct session_id session_id_remote;
-
- if (!buf_read (buf, &count, sizeof (count)))
- goto error;
- for (i = 0; i < count; ++i)
- {
- if (!buf_read (buf, &net_pid, sizeof (net_pid)))
- goto error;
- if (ack->len >= RELIABLE_ACK_SIZE)
- goto error;
- pid = ntohpid (net_pid);
- ack->packet_id[ack->len++] = pid;
- }
- if (count)
- {
- if (!session_id_read (&session_id_remote, buf))
- goto error;
- if (!session_id_defined (&session_id_remote) ||
- !session_id_equal (&session_id_remote, sid))
- {
- dmsg (D_REL_LOW,
- "ACK read BAD SESSION-ID FROM REMOTE, local=%s, remote=%s",
- session_id_print (sid, &gc), session_id_print (&session_id_remote, &gc));
- goto error;
- }
- }
- gc_free (&gc);
- return true;
-
-error:
- gc_free (&gc);
- return false;
-}
-
-#define ACK_SIZE(n) (sizeof (uint8_t) + ((n) ? SID_SIZE : 0) + sizeof (packet_id_type) * (n))
-
-/* write a packet ID acknowledgement record to buf, */
-/* removing all acknowledged entries from ack */
-bool
-reliable_ack_write (struct reliable_ack * ack,
- struct buffer * buf,
- const struct session_id * sid, int max, bool prepend)
-{
- int i, j;
- uint8_t n;
- struct buffer sub;
-
- n = ack->len;
- if (n > max)
- n = max;
- sub = buf_sub (buf, ACK_SIZE(n), prepend);
- if (!BDEF (&sub))
- goto error;
- ASSERT (buf_write (&sub, &n, sizeof (n)));
- for (i = 0; i < n; ++i)
- {
- packet_id_type pid = ack->packet_id[i];
- packet_id_type net_pid = htonpid (pid);
- ASSERT (buf_write (&sub, &net_pid, sizeof (net_pid)));
- dmsg (D_REL_DEBUG, "ACK write ID " packet_id_format " (ack->len=%d, n=%d)", (packet_id_print_type)pid, ack->len, n);
- }
- if (n)
- {
- ASSERT (session_id_defined (sid));
- ASSERT (session_id_write (sid, &sub));
- for (i = 0, j = n; j < ack->len;)
- ack->packet_id[i++] = ack->packet_id[j++];
- ack->len = i;
- }
-
- return true;
-
-error:
- return false;
-}
-
-/* add to extra_frame the maximum number of bytes we will need for reliable_ack_write */
-void
-reliable_ack_adjust_frame_parameters (struct frame* frame, int max)
-{
- frame_add_to_extra_frame (frame, ACK_SIZE (max));
-}
-
-/* print a reliable ACK record coming off the wire */
-const char *
-reliable_ack_print (struct buffer *buf, bool verbose, struct gc_arena *gc)
-{
- int i;
- uint8_t n_ack;
- struct session_id sid_ack;
- packet_id_type pid;
- struct buffer out = alloc_buf_gc (256, gc);
-
- buf_printf (&out, "[");
- if (!buf_read (buf, &n_ack, sizeof (n_ack)))
- goto done;
- for (i = 0; i < n_ack; ++i)
- {
- if (!buf_read (buf, &pid, sizeof (pid)))
- goto done;
- pid = ntohpid (pid);
- buf_printf (&out, " " packet_id_format, (packet_id_print_type)pid);
- }
- if (n_ack)
- {
- if (!session_id_read (&sid_ack, buf))
- goto done;
- if (verbose)
- buf_printf (&out, " sid=%s", session_id_print (&sid_ack, gc));
- }
-
- done:
- buf_printf (&out, " ]");
- return BSTR (&out);
-}
-
-/*
- * struct reliable member functions.
- */
-
-void
-reliable_init (struct reliable *rel, int buf_size, int offset, int array_size)
-{
- int i;
-
- CLEAR (*rel);
- ASSERT (array_size > 0 && array_size <= RELIABLE_CAPACITY);
- rel->size = array_size;
- rel->offset = offset;
- for (i = 0; i < rel->size; ++i)
- {
- struct reliable_entry *e = &rel->array[i];
- e->buf = alloc_buf (buf_size);
- ASSERT (buf_init (&e->buf, offset));
- }
-}
-
-void
-reliable_free (struct reliable *rel)
-{
- int i;
- for (i = 0; i < rel->size; ++i)
- {
- struct reliable_entry *e = &rel->array[i];
- free_buf (&e->buf);
- }
-}
-
-/* no active buffers? */
-bool
-reliable_empty (const struct reliable *rel)
-{
- int i;
- for (i = 0; i < rel->size; ++i)
- {
- const struct reliable_entry *e = &rel->array[i];
- if (e->active)
- return false;
- }
- return true;
-}
-
-/* del acknowledged items from send buf */
-void
-reliable_send_purge (struct reliable *rel, struct reliable_ack *ack)
-{
- int i, j;
- for (i = 0; i < ack->len; ++i)
- {
- packet_id_type pid = ack->packet_id[i];
- for (j = 0; j < rel->size; ++j)
- {
- struct reliable_entry *e = &rel->array[j];
- if (e->active && e->packet_id == pid)
- {
- dmsg (D_REL_DEBUG,
- "ACK received for pid " packet_id_format ", deleting from send buffer",
- (packet_id_print_type)pid);
-#if 0
- /* DEBUGGING -- how close were we timing out on ACK failure and resending? */
- {
- if (e->next_try)
- {
- const interval_t wake = e->next_try - now;
- msg (M_INFO, "ACK " packet_id_format ", wake=%d", pid, wake);
- }
- }
-#endif
- e->active = false;
- break;
- }
- }
- }
-}
-
-/* print the current sequence of active packet IDs */
-static const char *
-reliable_print_ids (const struct reliable *rel, struct gc_arena *gc)
-{
- struct buffer out = alloc_buf_gc (256, gc);
- int i;
-
- buf_printf (&out, "[" packet_id_format "]", (packet_id_print_type)rel->packet_id);
- for (i = 0; i < rel->size; ++i)
- {
- const struct reliable_entry *e = &rel->array[i];
- if (e->active)
- buf_printf (&out, " " packet_id_format, (packet_id_print_type)e->packet_id);
- }
- return BSTR (&out);
-}
-
-/* true if at least one free buffer available */
-bool
-reliable_can_get (const struct reliable *rel)
-{
- struct gc_arena gc = gc_new ();
- int i;
- for (i = 0; i < rel->size; ++i)
- {
- const struct reliable_entry *e = &rel->array[i];
- if (!e->active)
- return true;
- }
- dmsg (D_REL_LOW, "ACK no free receive buffer available: %s", reliable_print_ids (rel, &gc));
- gc_free (&gc);
- return false;
-}
-
-/* make sure that incoming packet ID isn't a replay */
-bool
-reliable_not_replay (const struct reliable *rel, packet_id_type id)
-{
- struct gc_arena gc = gc_new ();
- int i;
- if (id < rel->packet_id)
- goto bad;
- for (i = 0; i < rel->size; ++i)
- {
- const struct reliable_entry *e = &rel->array[i];
- if (e->active && e->packet_id == id)
- goto bad;
- }
- gc_free (&gc);
- return true;
-
- bad:
- dmsg (D_REL_DEBUG, "ACK " packet_id_format " is a replay: %s", (packet_id_print_type)id, reliable_print_ids (rel, &gc));
- gc_free (&gc);
- return false;
-}
-
-/* make sure that incoming packet ID won't deadlock the receive buffer */
-bool
-reliable_wont_break_sequentiality (const struct reliable *rel, packet_id_type id)
-{
- struct gc_arena gc = gc_new ();
- int ret;
-
- if ((int)id < (int)rel->packet_id + rel->size)
- {
- ret = true;
- }
- else
- {
- dmsg (D_REL_LOW, "ACK " packet_id_format " breaks sequentiality: %s",
- (packet_id_print_type)id, reliable_print_ids (rel, &gc));
- ret = false;
- }
- gc_free (&gc);
- return ret;
-}
-
-/* grab a free buffer */
-struct buffer *
-reliable_get_buf (struct reliable *rel)
-{
- int i;
- for (i = 0; i < rel->size; ++i)
- {
- struct reliable_entry *e = &rel->array[i];
- if (!e->active)
- {
- ASSERT (buf_init (&e->buf, rel->offset));
- return &e->buf;
- }
- }
- return NULL;
-}
-
-/* grab a free buffer, fail if buffer clogged by unacknowledged low packet IDs */
-struct buffer *
-reliable_get_buf_output_sequenced (struct reliable *rel)
-{
- struct gc_arena gc = gc_new ();
- int i;
- packet_id_type min_id = 0;
- bool min_id_defined = false;
- struct buffer *ret = NULL;
-
- /* find minimum active packet_id */
- for (i = 0; i < rel->size; ++i)
- {
- const struct reliable_entry *e = &rel->array[i];
- if (e->active)
- {
- if (!min_id_defined || e->packet_id < min_id)
- {
- min_id_defined = true;
- min_id = e->packet_id;
- }
- }
- }
-
- if (!min_id_defined || (int)(rel->packet_id - min_id) < rel->size)
- {
- ret = reliable_get_buf (rel);
- }
- else
- {
- dmsg (D_REL_LOW, "ACK output sequence broken: %s", reliable_print_ids (rel, &gc));
- }
- gc_free (&gc);
- return ret;
-}
-
-/* get active buffer for next sequentially increasing key ID */
-struct buffer *
-reliable_get_buf_sequenced (struct reliable *rel)
-{
- int i;
- for (i = 0; i < rel->size; ++i)
- {
- struct reliable_entry *e = &rel->array[i];
- if (e->active && e->packet_id == rel->packet_id)
- {
- return &e->buf;
- }
- }
- return NULL;
-}
-
-/* return true if reliable_send would return a non-NULL result */
-bool
-reliable_can_send (const struct reliable *rel)
-{
- struct gc_arena gc = gc_new ();
- int i;
- int n_active = 0, n_current = 0;
- for (i = 0; i < rel->size; ++i)
- {
- const struct reliable_entry *e = &rel->array[i];
- if (e->active)
- {
- ++n_active;
- if (now >= e->next_try)
- ++n_current;
- }
- }
- dmsg (D_REL_DEBUG, "ACK reliable_can_send active=%d current=%d : %s",
- n_active,
- n_current,
- reliable_print_ids (rel, &gc));
-
- gc_free (&gc);
- return n_current > 0;
-}
-
-/* return a unique point-in-time to trigger retry */
-static time_t
-reliable_unique_retry (struct reliable *rel, time_t retry)
-{
- int i;
- while (true)
- {
- for (i = 0; i < rel->size; ++i)
- {
- struct reliable_entry *e = &rel->array[i];
- if (e->active && e->next_try == retry)
- goto again;
- }
- break;
- again:
- ++retry;
- }
- return retry;
-}
-
-/* return next buffer to send to remote */
-struct buffer *
-reliable_send (struct reliable *rel, int *opcode)
-{
- int i;
- struct reliable_entry *best = NULL;
- const time_t local_now = now;
-
- for (i = 0; i < rel->size; ++i)
- {
- struct reliable_entry *e = &rel->array[i];
- if (e->active && local_now >= e->next_try)
- {
- if (!best || e->packet_id < best->packet_id)
- best = e;
- }
- }
- if (best)
- {
-#ifdef EXPONENTIAL_BACKOFF
- /* exponential backoff */
- best->next_try = reliable_unique_retry (rel, local_now + best->timeout);
- best->timeout *= 2;
-#else
- /* constant timeout, no backoff */
- best->next_try = local_now + best->timeout;
-#endif
- *opcode = best->opcode;
- dmsg (D_REL_DEBUG, "ACK reliable_send ID " packet_id_format " (size=%d to=%d)",
- (packet_id_print_type)best->packet_id, best->buf.len,
- (int)(best->next_try - local_now));
- return &best->buf;
- }
- return NULL;
-}
-
-/* schedule all pending packets for immediate retransmit */
-void
-reliable_schedule_now (struct reliable *rel)
-{
- int i;
- dmsg (D_REL_DEBUG, "ACK reliable_schedule_now");
- for (i = 0; i < rel->size; ++i)
- {
- struct reliable_entry *e = &rel->array[i];
- if (e->active)
- {
- e->next_try = now;
- e->timeout = rel->initial_timeout;
- }
- }
-}
-
-/* in how many seconds should we wake up to check for timeout */
-/* if we return BIG_TIMEOUT, nothing to wait for */
-interval_t
-reliable_send_timeout (const struct reliable *rel)
-{
- struct gc_arena gc = gc_new ();
- interval_t ret = BIG_TIMEOUT;
- int i;
- const time_t local_now = now;
-
- for (i = 0; i < rel->size; ++i)
- {
- const struct reliable_entry *e = &rel->array[i];
- if (e->active)
- {
- if (e->next_try <= local_now)
- {
- ret = 0;
- break;
- }
- else
- {
- ret = min_int (ret, e->next_try - local_now);
- }
- }
- }
-
- dmsg (D_REL_DEBUG, "ACK reliable_send_timeout %d %s",
- (int) ret,
- reliable_print_ids (rel, &gc));
-
- gc_free (&gc);
- return ret;
-}
-
-/*
- * Enable an incoming buffer previously returned by a get function as active.
- */
-
-void
-reliable_mark_active_incoming (struct reliable *rel, struct buffer *buf,
- packet_id_type pid, int opcode)
-{
- int i;
- for (i = 0; i < rel->size; ++i)
- {
- struct reliable_entry *e = &rel->array[i];
- if (buf == &e->buf)
- {
- e->active = true;
-
- /* packets may not arrive in sequential order */
- e->packet_id = pid;
-
- /* check for replay */
- ASSERT (pid >= rel->packet_id);
-
- e->opcode = opcode;
- e->next_try = 0;
- e->timeout = 0;
- dmsg (D_REL_DEBUG, "ACK mark active incoming ID " packet_id_format, (packet_id_print_type)e->packet_id);
- return;
- }
- }
- ASSERT (0); /* buf not found in rel */
-}
-
-/*
- * Enable an outgoing buffer previously returned by a get function as active.
- */
-
-void
-reliable_mark_active_outgoing (struct reliable *rel, struct buffer *buf, int opcode)
-{
- int i;
- for (i = 0; i < rel->size; ++i)
- {
- struct reliable_entry *e = &rel->array[i];
- if (buf == &e->buf)
- {
- /* Write mode, increment packet_id (i.e. sequence number)
- linearly and prepend id to packet */
- packet_id_type net_pid;
- e->packet_id = rel->packet_id++;
- net_pid = htonpid (e->packet_id);
- ASSERT (buf_write_prepend (buf, &net_pid, sizeof (net_pid)));
- e->active = true;
- e->opcode = opcode;
- e->next_try = 0;
- e->timeout = rel->initial_timeout;
- dmsg (D_REL_DEBUG, "ACK mark active outgoing ID " packet_id_format, (packet_id_print_type)e->packet_id);
- return;
- }
- }
- ASSERT (0); /* buf not found in rel */
-}
-
-/* delete a buffer previously activated by reliable_mark_active() */
-void
-reliable_mark_deleted (struct reliable *rel, struct buffer *buf, bool inc_pid)
-{
- int i;
- for (i = 0; i < rel->size; ++i)
- {
- struct reliable_entry *e = &rel->array[i];
- if (buf == &e->buf)
- {
- e->active = false;
- if (inc_pid)
- rel->packet_id = e->packet_id + 1;
- return;
- }
- }
- ASSERT (0);
-}
-
-#if 0
-
-void
-reliable_ack_debug_print (const struct reliable_ack *ack, char *desc)
-{
- int i;
-
- printf ("********* struct reliable_ack %s\n", desc);
- for (i = 0; i < ack->len; ++i)
- {
- printf (" %d: " packet_id_format "\n", i, (packet_id_print_type) ack->packet_id[i]);
- }
-}
-
-void
-reliable_debug_print (const struct reliable *rel, char *desc)
-{
- int i;
- update_time ();
-
- printf ("********* struct reliable %s\n", desc);
- printf (" initial_timeout=%d\n", (int)rel->initial_timeout);
- printf (" packet_id=" packet_id_format "\n", rel->packet_id);
- printf (" now=" time_format "\n", now);
- for (i = 0; i < rel->size; ++i)
- {
- const struct reliable_entry *e = &rel->array[i];
- if (e->active)
- {
- printf (" %d: packet_id=" packet_id_format " len=%d", i, e->packet_id, e->buf.len);
- printf (" next_try=" time_format, e->next_try);
- printf ("\n");
- }
- }
-}
-
-#endif
-
-#else
-static void dummy(void) {}
-#endif /* USE_CRYPTO && USE_SSL*/
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-05 16:58:09 +0000