Adding upstream version 2:4.17.12+dfsg.upstream/2%4.17.12+dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 418 insertions, 0 deletions

diff --git a/ctdb/tools/ctdb_killtcp.c b/ctdb/tools/ctdb_killtcp.c
new file mode 100644
index 0000000..007422f
--- /dev/null
+++ b/ctdb/tools/ctdb_killtcp.c
@@ -0,0 +1,418 @@
+/*
+   CTDB TCP connection killing utility
+
+   Copyright (C) Martin Schwenke <martin@meltin.net> 2016
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   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; if not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "replace.h"
+#include "system/network.h"
+
+#include <talloc.h>
+#include <tevent.h>
+
+#include "lib/util/debug.h"
+#include "lib/util/tevent_unix.h"
+
+#include "protocol/protocol.h"
+#include "protocol/protocol_util.h"
+
+#include "common/db_hash.h"
+#include "common/system_socket.h"
+#include "common/logging.h"
+
+
+struct reset_connections_state {
+	struct tevent_context *ev;
+	int capture_fd;
+	struct tevent_fd *fde;
+	struct db_hash_context *connections;
+	void *private_data;
+	unsigned int attempts;
+	unsigned int max_attempts;
+	struct timeval retry_interval;
+	unsigned int batch_count;
+	unsigned int batch_size;
+};
+
+
+static void reset_connections_capture_tcp_handler(struct tevent_context *ev,
+						  struct tevent_fd *fde,
+						  uint16_t flags,
+						  void *private_data);
+static void reset_connections_batch(struct tevent_req *subreq);
+static int reset_connections_tickle_connection(
+					uint8_t *keybuf, size_t keylen,
+					uint8_t *databuf, size_t datalen,
+					void *private_data);
+
+static struct tevent_req *reset_connections_send(
+			      TALLOC_CTX *mem_ctx,
+			      struct tevent_context *ev,
+			      const char *iface,
+			      struct ctdb_connection_list *conn_list)
+{
+	struct tevent_req *req, *subreq;
+	struct reset_connections_state *state;
+	unsigned int i;
+	int ret;
+
+	req = tevent_req_create(mem_ctx, &state,
+				struct reset_connections_state);
+	if (req == NULL) {
+		return NULL;
+	}
+
+	state->ev = ev;
+
+	if (conn_list->num == 0) {
+		/* No connections, done! */
+		tevent_req_done(req);
+		return tevent_req_post(req, ev);
+	}
+
+	ret = db_hash_init(state, "connections", 2048, DB_HASH_SIMPLE,
+			   &state->connections);
+	if (ret != 0) {
+		D_ERR("Failed to initialise connection hash (%s)\n",
+		      strerror(ret));
+		tevent_req_error(req, ret);
+		return tevent_req_post(req, ev);
+	}
+
+	DBG_DEBUG("Adding %u connections to hash\n", conn_list->num);
+	for (i = 0; i < conn_list->num; i++) {
+		struct ctdb_connection *c = &conn_list->conn[i];
+
+		DBG_DEBUG("Adding connection to hash: %s\n",
+			  ctdb_connection_to_string(conn_list, c, true));
+
+		/* Connection is stored as a key in the connections hash */
+		ret = db_hash_add(state->connections,
+				  (uint8_t *)discard_const(c), sizeof(*c),
+				  NULL, 0);
+		if (ret != 0) {
+			D_ERR("Error adding connection to hash (%s)\n",
+			      strerror(ret));
+			tevent_req_error(req, ret);
+			return tevent_req_post(req, ev);
+		}
+	}
+
+	state->attempts = 0;
+	state->max_attempts = 50;
+
+	state->retry_interval.tv_sec = 0;
+	state->retry_interval.tv_usec = 100 * 1000;
+
+	state->batch_count = 0;
+	state->batch_size = 300;
+
+	state->capture_fd =
+		ctdb_sys_open_capture_socket(iface, &state->private_data);
+	if (state->capture_fd == -1) {
+		D_ERR("Failed to open capture socket on iface '%s' (%s)\n",
+		      iface, strerror(errno));
+			tevent_req_error(req, EIO);
+			return tevent_req_post(req, ev);
+	}
+
+	state->fde = tevent_add_fd(ev, state, state->capture_fd,
+				   TEVENT_FD_READ,
+				   reset_connections_capture_tcp_handler,
+				   state);
+	if (tevent_req_nomem(state->fde, req)) {
+		return tevent_req_post(req, ev);
+	}
+	tevent_fd_set_auto_close(state->fde);
+
+	subreq = tevent_wakeup_send(state, ev, tevent_timeval_current_ofs(0,0));
+	if (tevent_req_nomem(subreq, req)) {
+		return tevent_req_post(req, ev);
+	}
+	tevent_req_set_callback(subreq, reset_connections_batch, req);
+
+	return req;
+}
+
+/*
+  called when we get a read event on the raw socket
+ */
+static void reset_connections_capture_tcp_handler(struct tevent_context *ev,
+						  struct tevent_fd *fde,
+						  uint16_t flags,
+						  void *private_data)
+{
+	struct reset_connections_state *state = talloc_get_type_abort(
+		private_data, struct reset_connections_state);
+	/* 0 the parts that don't get set by ctdb_sys_read_tcp_packet */
+	struct ctdb_connection conn;
+	uint32_t ack_seq, seq;
+	int rst;
+	uint16_t window;
+	int ret;
+
+	ret = ctdb_sys_read_tcp_packet(state->capture_fd,
+				       state->private_data,
+				       &conn.server, &conn.client,
+				       &ack_seq, &seq, &rst, &window);
+	if (ret != 0) {
+		/* Not a TCP-ACK?  Unexpected protocol? */
+		DBG_DEBUG("Failed to parse packet, errno=%d\n", ret);
+		return;
+	}
+
+	if (window == htons(1234) && (rst || seq == 0)) {
+		/* Ignore packets that we sent! */
+		DBG_DEBUG("Ignoring sent packet: %s, "
+			  "seq=%"PRIu32", ack_seq=%"PRIu32", "
+			  "rst=%d, window=%"PRIu16"\n",
+			  ctdb_connection_to_string(state, &conn, false),
+			  seq, ack_seq, rst, ntohs(window));
+		return;
+	}
+
+	/* Check if this connection is one being reset, if found then delete */
+	ret = db_hash_delete(state->connections,
+			     (uint8_t*)&conn, sizeof(conn));
+	if (ret == ENOENT) {
+		/* Packet for some other connection, ignore */
+		DBG_DEBUG("Ignoring packet for unknown connection: %s\n",
+			  ctdb_connection_to_string(state, &conn, true));
+		return;
+	}
+	if (ret != 0) {
+		DBG_WARNING("Internal error (%s)\n", strerror(ret));
+		return;
+	}
+
+	D_INFO("Sending a TCP RST to for connection %s\n",
+	       ctdb_connection_to_string(state, &conn, true));
+
+	ret = ctdb_sys_send_tcp(&conn.server, &conn.client, ack_seq, seq, 1);
+	if (ret != 0) {
+		DBG_ERR("Error sending TCP RST for connection\n");
+	}
+}
+
+/*
+ * Called periodically until all sentenced connections have been reset
+ * or enough attempts have been made
+ */
+static void reset_connections_batch(struct tevent_req *subreq)
+{
+	struct tevent_req *req = tevent_req_callback_data(
+		subreq, struct tevent_req);
+	struct reset_connections_state *state = tevent_req_data(
+		req, struct reset_connections_state);
+	bool status;
+	int count, ret;
+
+	status = tevent_wakeup_recv(subreq);
+	TALLOC_FREE(subreq);
+
+	if (! status) {
+		DBG_WARNING("Unexpected error on timer expiry\n");
+		/* Keep going... */
+	}
+
+	/* loop over up to batch_size connections sending tickle ACKs */
+	state->batch_count = 0;
+	ret = db_hash_traverse(state->connections,
+			       reset_connections_tickle_connection,
+			       state, NULL);
+	if (ret != 0) {
+		DBG_WARNING("Unexpected error traversing connections (%s)\n",
+			    strerror(ret));
+	}
+
+	state->attempts++;
+
+	/*
+	 * If there are no more connections to kill or we have tried
+	 * too many times we're finished
+	 */
+	ret = db_hash_traverse(state->connections, NULL, NULL, &count);
+	if (ret != 0) {
+		/* What now?  Try again until max_attempts reached */
+		DBG_WARNING("Unexpected error traversing connections (%s)\n",
+			    strerror(ret));
+		count = 1;
+	}
+	if (count == 0 ||
+	    state->attempts >= state->max_attempts) {
+		tevent_req_done(req);
+		return;
+	}
+
+	/* Schedule next attempt */
+	subreq = tevent_wakeup_send(state, state->ev,
+				    tevent_timeval_current_ofs(
+					    state->retry_interval.tv_sec,
+					    state->retry_interval.tv_usec));
+	if (tevent_req_nomem(subreq, req)) {
+		return;
+	}
+	tevent_req_set_callback(subreq, reset_connections_batch, req);
+}
+
+static int reset_connections_tickle_connection(
+					uint8_t *keybuf, size_t keylen,
+					uint8_t *databuf, size_t datalen,
+					void *private_data)
+{
+	struct reset_connections_state *state = talloc_get_type_abort(
+		private_data, struct reset_connections_state);
+	struct ctdb_connection *conn;
+	int ret;
+
+	if (keylen != sizeof(*conn)) {
+		DBG_WARNING("Unexpected data in connection hash\n");
+		return 0;
+	}
+
+	conn = (struct ctdb_connection *)keybuf;
+
+	state->batch_count++;
+	if (state->batch_count > state->batch_size) {
+		/* Terminate the traverse */
+		return 1;
+	}
+
+	DBG_DEBUG("Sending tickle ACK for connection '%s'\n",
+		  ctdb_connection_to_string(state, conn, true));
+	ret = ctdb_sys_send_tcp(&conn->server, &conn->client, 0, 0, 0);
+	if (ret != 0) {
+		DBG_ERR("Error sending tickle ACK\n");
+		/* continue */
+	}
+
+	return 0;
+}
+
+static bool reset_connections_recv(struct tevent_req *req, int *perr)
+{
+	int err;
+
+	if (tevent_req_is_unix_error(req, &err)) {
+		if (perr != NULL) {
+			*perr = err;
+		}
+		return false;
+	}
+
+	return true;
+}
+
+static void usage(const char *prog)
+{
+	printf("usage: %s <interface> [ <srcip:port> <dstip:port> ]\n", prog);
+	exit(1);
+}
+
+int main(int argc, char **argv)
+{
+	struct ctdb_connection conn;
+	struct tevent_context *ev = NULL;
+	TALLOC_CTX *mem_ctx = NULL;
+	struct ctdb_connection_list *conn_list = NULL;
+	const char *t;
+	struct tevent_req *req;
+	int debug_level;
+	bool status;
+	bool ok;
+	int ret;
+
+	/* Set the debug level */
+	t = getenv("CTDB_DEBUGLEVEL");
+	if (t != NULL) {
+		ok = debug_level_parse(t, &debug_level);
+		if (!ok) {
+			debug_level = DEBUG_ERR;
+		}
+		debuglevel_set(debug_level);
+	}
+
+	if (argc != 2 && argc != 4) {
+		usage(argv[0]);
+	}
+
+	if (argc == 4) {
+		ret = ctdb_sock_addr_from_string(argv[2], &conn.client, true);
+		if (ret != 0) {
+			D_ERR("Bad IP:port '%s'\n", argv[2]);
+			goto fail;
+		}
+
+		ret = ctdb_sock_addr_from_string(argv[3], &conn.server, true);
+		if (ret != 0) {
+			D_ERR("Bad IP:port '%s'\n", argv[3]);
+			goto fail;
+		}
+
+
+		conn_list = talloc_zero(mem_ctx, struct ctdb_connection_list);
+		if (conn_list == NULL) {
+			ret = ENOMEM;
+			DBG_ERR("Internal error (%s)\n", strerror(ret));
+			goto fail;
+		}
+		ret = ctdb_connection_list_add(conn_list, &conn);
+		if (ret != 0) {
+			DBG_ERR("Internal error (%s)\n", strerror(ret));
+			goto fail;
+		}
+	} else {
+		ret = ctdb_connection_list_read(mem_ctx, 0, true, &conn_list);
+		if (ret != 0) {
+			D_ERR("Unable to parse connections (%s)\n",
+			      strerror(ret));
+			goto fail;
+		}
+	}
+
+	mem_ctx = talloc_new(NULL);
+	if (mem_ctx == NULL) {
+		DEBUG(DEBUG_ERR, (__location__ " out of memory\n"));
+		goto fail;
+	}
+
+	ev = tevent_context_init(mem_ctx);
+	if (ev == NULL) {
+		DEBUG(DEBUG_ERR, ("Failed to initialise tevent\n"));
+		goto fail;
+	}
+
+	req = reset_connections_send(mem_ctx, ev, argv[1], conn_list);
+	if (req == NULL) {
+		goto fail;
+	}
+
+	tevent_req_poll(req, ev);
+
+	status = reset_connections_recv(req, &ret);
+	if (! status) {
+		D_ERR("Failed to kill connections (%s)\n", strerror(ret));
+		goto fail;
+	}
+
+	talloc_free(mem_ctx);
+
+	return 0;
+
+fail:
+	TALLOC_FREE(mem_ctx);
+	return -1;
+}