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authorAlberto Gonzalez Iniesta <agi@inittab.org>2016-12-27 18:25:47 +0100
committerAlberto Gonzalez Iniesta <agi@inittab.org>2016-12-27 18:25:47 +0100
commit79f3537f69e125f19f59c36aa090120a63186a54 (patch)
tree2089a3b7dac990841dbc2e4d9b2f535b82dbb0af /src/openvpn/gremlin.c
parentf2137fedb30cb87448eb03b2f288920df6187571 (diff)
parent3a2bbdb05ca6a6996e424c9fb225cb0d53804125 (diff)
Merge tag 'upstream/2.4.0'
Upstream version 2.4.0
Diffstat (limited to 'src/openvpn/gremlin.c')
-rw-r--r--src/openvpn/gremlin.c204
1 files changed, 110 insertions, 94 deletions
diff --git a/src/openvpn/gremlin.c b/src/openvpn/gremlin.c
index f0aa7f6..5bff5e8 100644
--- a/src/openvpn/gremlin.c
+++ b/src/openvpn/gremlin.c
@@ -5,7 +5,7 @@
* packet encryption, packet authentication, and
* packet compression.
*
- * Copyright (C) 2002-2010 OpenVPN Technologies, Inc. <sales@openvpn.net>
+ * Copyright (C) 2002-2017 OpenVPN Technologies, Inc. <sales@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
@@ -82,32 +82,34 @@ static const int down_high[] = { 10, 60, 120 };
* { number of packets, packet size }
*/
static const struct packet_flood_parms packet_flood_data[] =
- {{10, 100}, {10, 1500}, {100, 1500}};
+{{10, 100}, {10, 1500}, {100, 1500}};
struct packet_flood_parms
-get_packet_flood_parms (int level)
+get_packet_flood_parms(int level)
{
- ASSERT (level > 0 && level < 4);
- return packet_flood_data [level - 1];
+ ASSERT(level > 0 && level < 4);
+ return packet_flood_data [level - 1];
}
/*
* Return true with probability 1/n
*/
-static bool flip(int n) {
- return (get_random() % n) == 0;
+static bool
+flip(int n) {
+ return (get_random() % n) == 0;
}
/*
* Return uniformly distributed random number between
* low and high.
*/
-static int roll(int low, int high) {
- int ret;
- ASSERT (low <= high);
- ret = low + (get_random() % (high - low + 1));
- ASSERT (ret >= low && ret <= high);
- return ret;
+static int
+roll(int low, int high) {
+ int ret;
+ ASSERT(low <= high);
+ ret = low + (get_random() % (high - low + 1));
+ ASSERT(ret >= low && ret <= high);
+ return ret;
}
static bool initialized; /* GLOBAL */
@@ -118,104 +120,118 @@ static time_t next; /* GLOBAL */
* Return false if we should drop a packet.
*/
bool
-ask_gremlin (int flags)
+ask_gremlin(int flags)
{
- const int up_down_level = GREMLIN_UP_DOWN_LEVEL (flags);
- const int drop_level = GREMLIN_DROP_LEVEL (flags);
+ const int up_down_level = GREMLIN_UP_DOWN_LEVEL(flags);
+ const int drop_level = GREMLIN_DROP_LEVEL(flags);
- if (!initialized)
+ if (!initialized)
{
- initialized = true;
-
- if (up_down_level)
- up = false;
- else
- up = true;
-
- next = now;
+ initialized = true;
+
+ if (up_down_level)
+ {
+ up = false;
+ }
+ else
+ {
+ up = true;
+ }
+
+ next = now;
}
- if (up_down_level) /* change up/down state? */
+ if (up_down_level) /* change up/down state? */
{
- if (now >= next)
- {
- int delta;
- if (up)
- {
- delta = roll (down_low[up_down_level-1], down_high[up_down_level-1]);
- up = false;
- }
- else
- {
- delta = roll (up_low[up_down_level-1], up_high[up_down_level-1]);
- up = true;
- }
-
- msg (D_GREMLIN,
- "GREMLIN: CONNECTION GOING %s FOR %d SECONDS",
- (up ? "UP" : "DOWN"),
- delta);
- next = now + delta;
- }
+ if (now >= next)
+ {
+ int delta;
+ if (up)
+ {
+ delta = roll(down_low[up_down_level-1], down_high[up_down_level-1]);
+ up = false;
+ }
+ else
+ {
+ delta = roll(up_low[up_down_level-1], up_high[up_down_level-1]);
+ up = true;
+ }
+
+ msg(D_GREMLIN,
+ "GREMLIN: CONNECTION GOING %s FOR %d SECONDS",
+ (up ? "UP" : "DOWN"),
+ delta);
+ next = now + delta;
+ }
}
- if (drop_level)
+ if (drop_level)
{
- if (up && flip (drop_freq[drop_level-1]))
- {
- dmsg (D_GREMLIN_VERBOSE, "GREMLIN: Random packet drop");
- return false;
- }
+ if (up && flip(drop_freq[drop_level-1]))
+ {
+ dmsg(D_GREMLIN_VERBOSE, "GREMLIN: Random packet drop");
+ return false;
+ }
}
- return up;
+ return up;
}
/*
* Possibly corrupt a packet.
*/
-void corrupt_gremlin (struct buffer *buf, int flags) {
- const int corrupt_level = GREMLIN_CORRUPT_LEVEL (flags);
- if (corrupt_level)
+void
+corrupt_gremlin(struct buffer *buf, int flags) {
+ const int corrupt_level = GREMLIN_CORRUPT_LEVEL(flags);
+ if (corrupt_level)
{
- if (flip (corrupt_freq[corrupt_level-1]))
- {
- do
- {
- if (buf->len > 0)
- {
- uint8_t r = roll (0, 255);
- int method = roll (0, 5);
-
- switch (method) {
- case 0: /* corrupt the first byte */
- *BPTR (buf) = r;
- break;
- case 1: /* corrupt the last byte */
- *(BPTR (buf) + buf->len - 1) = r;
- break;
- case 2: /* corrupt a random byte */
- *(BPTR(buf) + roll (0, buf->len - 1)) = r;
- break;
- case 3: /* append a random byte */
- buf_write (buf, &r, 1);
- break;
- case 4: /* reduce length by 1 */
- --buf->len;
- break;
- case 5: /* reduce length by a random amount */
- buf->len -= roll (0, buf->len - 1);
- break;
- }
- dmsg (D_GREMLIN_VERBOSE, "GREMLIN: Packet Corruption, method=%d", method);
- }
- else
- break;
- } while (flip (2)); /* a 50% chance we will corrupt again */
- }
+ if (flip(corrupt_freq[corrupt_level-1]))
+ {
+ do
+ {
+ if (buf->len > 0)
+ {
+ uint8_t r = roll(0, 255);
+ int method = roll(0, 5);
+
+ switch (method) {
+ case 0: /* corrupt the first byte */
+ *BPTR(buf) = r;
+ break;
+
+ case 1: /* corrupt the last byte */
+ *(BPTR(buf) + buf->len - 1) = r;
+ break;
+
+ case 2: /* corrupt a random byte */
+ *(BPTR(buf) + roll(0, buf->len - 1)) = r;
+ break;
+
+ case 3: /* append a random byte */
+ buf_write(buf, &r, 1);
+ break;
+
+ case 4: /* reduce length by 1 */
+ --buf->len;
+ break;
+
+ case 5: /* reduce length by a random amount */
+ buf->len -= roll(0, buf->len - 1);
+ break;
+ }
+ dmsg(D_GREMLIN_VERBOSE, "GREMLIN: Packet Corruption, method=%d", method);
+ }
+ else
+ {
+ break;
+ }
+ } while (flip(2)); /* a 50% chance we will corrupt again */
+ }
}
}
-#else
-static void dummy(void) {}
-#endif
+#else /* ifdef ENABLE_DEBUG */
+static void
+dummy(void) {
+}
+#endif /* ifdef ENABLE_DEBUG */