1 files changed, 363 insertions, 0 deletions

diff --git a/src/action.c b/src/action.c
new file mode 100644
index 0000000..47f5f86
--- /dev/null
+++ b/src/action.c
@@ -0,0 +1,363 @@
+/*
+ * Action management functions.
+ *
+ * Copyright 2017 HAProxy Technologies, Christopher Faulet <cfaulet@haproxy.com>
+ *
+ * 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
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <haproxy/acl.h>
+#include <haproxy/action.h>
+#include <haproxy/api.h>
+#include <haproxy/cfgparse.h>
+#include <haproxy/errors.h>
+#include <haproxy/list.h>
+#include <haproxy/obj_type.h>
+#include <haproxy/pool.h>
+#include <haproxy/proxy.h>
+#include <haproxy/stick_table.h>
+#include <haproxy/task.h>
+#include <haproxy/tools.h>
+
+
+/* Check an action ruleset validity. It returns the number of error encountered
+ * and err_code is updated if a warning is emitted.
+ */
+int check_action_rules(struct list *rules, struct proxy *px, int *err_code)
+{
+	struct act_rule *rule;
+	char *errmsg = NULL;
+	int err = 0;
+
+	list_for_each_entry(rule, rules, list) {
+		if (rule->check_ptr && !rule->check_ptr(rule, px, &errmsg)) {
+			ha_alert("Proxy '%s': %s.\n", px->id, errmsg);
+			err++;
+		}
+		*err_code |= warnif_tcp_http_cond(px, rule->cond);
+		ha_free(&errmsg);
+	}
+
+	return err;
+}
+
+/* Find and check the target table used by an action track-sc*. This
+ * function should be called during the configuration validity check.
+ *
+ * The function returns 1 in success case, otherwise, it returns 0 and err is
+ * filled.
+ */
+int check_trk_action(struct act_rule *rule, struct proxy *px, char **err)
+{
+	struct stktable *target;
+
+	if (rule->arg.trk_ctr.table.n)
+		target = stktable_find_by_name(rule->arg.trk_ctr.table.n);
+	else
+		target = px->table;
+
+	if (!target) {
+		memprintf(err, "unable to find table '%s' referenced by track-sc%d",
+			  rule->arg.trk_ctr.table.n ?  rule->arg.trk_ctr.table.n : px->id,
+			  rule->action);
+		return 0;
+	}
+
+	if (!stktable_compatible_sample(rule->arg.trk_ctr.expr,  target->type)) {
+		memprintf(err, "stick-table '%s' uses a type incompatible with the 'track-sc%d' rule",
+			  rule->arg.trk_ctr.table.n ? rule->arg.trk_ctr.table.n : px->id,
+			  rule->action);
+		return 0;
+	}
+	else {
+		if (!in_proxies_list(target->proxies_list, px)) {
+			px->next_stkt_ref = target->proxies_list;
+			target->proxies_list = px;
+		}
+		free(rule->arg.trk_ctr.table.n);
+		rule->arg.trk_ctr.table.t = target;
+		/* Note: if we decide to enhance the track-sc syntax, we may be
+		 * able to pass a list of counters to track and allocate them
+		 * right here using stktable_alloc_data_type().
+		 */
+	}
+
+	if (rule->from == ACT_F_TCP_REQ_CNT && (px->cap & PR_CAP_FE)) {
+		if (!px->tcp_req.inspect_delay && !(rule->arg.trk_ctr.expr->fetch->val & SMP_VAL_FE_SES_ACC)) {
+			ha_warning("%s '%s' : a 'tcp-request content track-sc*' rule explicitly depending on request"
+				   " contents without any 'tcp-request inspect-delay' setting."
+				   " This means that this rule will randomly find its contents. This can be fixed by"
+				   " setting the tcp-request inspect-delay.\n",
+				   proxy_type_str(px), px->id);
+		}
+
+		/* The following warning is emitted because HTTP multiplexers are able to catch errors
+		 * or timeouts at the session level, before instantiating any stream.
+		 * Thus the tcp-request content ruleset will not be evaluated in such case. It means,
+		 * http_req and http_err counters will not be incremented as expected, even if the tracked
+		 * counter does not use the request content. To track invalid requests it should be
+		 * performed at the session level using a tcp-request session rule.
+		 */
+		if (px->mode == PR_MODE_HTTP &&
+		    !(rule->arg.trk_ctr.expr->fetch->use & (SMP_USE_L6REQ|SMP_USE_HRQHV|SMP_USE_HRQHP|SMP_USE_HRQBO)) &&
+		    (!rule->cond || !(rule->cond->use & (SMP_USE_L6REQ|SMP_USE_HRQHV|SMP_USE_HRQHP|SMP_USE_HRQBO)))) {
+			ha_warning("%s '%s' : a 'tcp-request content track-sc*' rule not depending on request"
+				   " contents for an HTTP frontend should be executed at the session level, using a"
+				   " 'tcp-request session' rule (mandatory to track invalid HTTP requests).\n",
+				   proxy_type_str(px), px->id);
+		}
+	}
+
+	return 1;
+}
+
+/* check a capture rule. This function should be called during the configuration
+ * validity check.
+ *
+ * The function returns 1 in success case, otherwise, it returns 0 and err is
+ * filled.
+ */
+int check_capture(struct act_rule *rule, struct proxy *px, char **err)
+{
+	if (rule->from == ACT_F_TCP_REQ_CNT && (px->cap & PR_CAP_FE) && !px->tcp_req.inspect_delay &&
+	    !(rule->arg.cap.expr->fetch->val & SMP_VAL_FE_SES_ACC)) {
+		ha_warning("%s '%s' : a 'tcp-request capture' rule explicitly depending on request"
+			   " contents without any 'tcp-request inspect-delay' setting."
+			   " This means that this rule will randomly find its contents. This can be fixed by"
+			   " setting the tcp-request inspect-delay.\n",
+			   proxy_type_str(px), px->id);
+	}
+
+	return 1;
+}
+
+int act_resolution_cb(struct resolv_requester *requester, struct dns_counters *counters)
+{
+	struct stream *stream;
+
+	if (requester->resolution == NULL)
+		return 0;
+
+	stream = objt_stream(requester->owner);
+	if (stream == NULL)
+		return 0;
+
+	task_wakeup(stream->task, TASK_WOKEN_MSG);
+
+	return 0;
+}
+
+/*
+ * Do resolve error management callback
+ * returns:
+ *  0 if we can trash answser items.
+ *  1 when safely ignored and we must kept answer items
+ */
+int act_resolution_error_cb(struct resolv_requester *requester, int error_code)
+{
+	struct stream *stream;
+
+	if (requester->resolution == NULL)
+		return 0;
+
+	stream = objt_stream(requester->owner);
+	if (stream == NULL)
+		return 0;
+
+	task_wakeup(stream->task, TASK_WOKEN_MSG);
+
+	return 0;
+}
+
+/* Parse a set-timeout rule statement. It first checks if the timeout name is
+ * valid and proxy is capable of handling it, and returns it in <rule->arg.timeout.type>.
+ * Then the timeout is parsed as a plain value and * returned in <rule->arg.timeout.value>.
+ * If there is a parsing error, the value is reparsed as an expression and
+ * returned in <rule->arg.timeout.expr>.
+ *
+ * Returns -1 if the name is invalid or neither a time or an expression can be
+ * parsed, or if the timeout value is 0.
+ */
+int cfg_parse_rule_set_timeout(const char **args, int idx, struct act_rule *rule,
+			       struct proxy *px, char **err)
+{
+	const char *res;
+	const char *timeout_name = args[idx++];
+
+	if (strcmp(timeout_name, "server") == 0) {
+		if (!(px->cap & PR_CAP_BE)) {
+			memprintf(err, "'%s' has no backend capability", px->id);
+			return -1;
+		}
+		rule->arg.timeout.type = ACT_TIMEOUT_SERVER;
+	}
+	else if (strcmp(timeout_name, "tunnel") == 0) {
+		if (!(px->cap & PR_CAP_BE)) {
+			memprintf(err, "'%s' has no backend capability", px->id);
+			return -1;
+		}
+		rule->arg.timeout.type = ACT_TIMEOUT_TUNNEL;
+	}
+	else if (strcmp(timeout_name, "client") == 0) {
+		if (!(px->cap & PR_CAP_FE)) {
+			memprintf(err, "'%s' has no frontend capability", px->id);
+			return -1;
+		}
+		rule->arg.timeout.type = ACT_TIMEOUT_CLIENT;
+	}
+	else {
+		memprintf(err,
+		          "'set-timeout' rule supports 'server'/'tunnel'/'client' (got '%s')",
+		          timeout_name);
+		return -1;
+	}
+
+	res = parse_time_err(args[idx], (unsigned int *)&rule->arg.timeout.value, TIME_UNIT_MS);
+	if (res == PARSE_TIME_OVER) {
+		memprintf(err, "timer overflow in argument '%s' to rule 'set-timeout %s' (maximum value is 2147483647 ms or ~24.8 days)",
+			  args[idx], timeout_name);
+		return -1;
+	}
+	else if (res == PARSE_TIME_UNDER) {
+		memprintf(err, "timer underflow in argument '%s' to rule 'set-timeout %s' (minimum value is 1 ms)",
+			  args[idx], timeout_name);
+		return -1;
+	}
+	/* res not NULL, parsing error */
+	else if (res) {
+		rule->arg.timeout.expr = sample_parse_expr((char **)args, &idx, px->conf.args.file,
+							   px->conf.args.line, err, &px->conf.args, NULL);
+		if (!rule->arg.timeout.expr) {
+			memprintf(err, "unexpected character '%c' in rule 'set-timeout %s'", *res, timeout_name);
+			return -1;
+		}
+	}
+	/* res NULL, parsing ok but value is 0 */
+	else if (!(rule->arg.timeout.value)) {
+		memprintf(err, "null value is not valid for a 'set-timeout %s' rule",
+			  timeout_name);
+		return -1;
+	}
+
+	return 0;
+}
+
+/* tries to find in list <keywords> a similar looking action as the one in
+ * <word>, and returns it otherwise NULL. <word> may be NULL or empty. An
+ * optional array of extra words to compare may be passed in <extra>, but it
+ * must then be terminated by a NULL entry. If unused it may be NULL.
+ */
+const char *action_suggest(const char *word, const struct list *keywords, const char **extra)
+{
+	uint8_t word_sig[1024];
+	uint8_t list_sig[1024];
+	const struct action_kw_list *kwl;
+	const struct action_kw *best_kw = NULL;
+	const char *best_ptr = NULL;
+	int dist, best_dist = INT_MAX;
+	int index;
+
+	if (!word || !*word)
+		return NULL;
+
+	make_word_fingerprint(word_sig, word);
+	list_for_each_entry(kwl, keywords, list) {
+		for (index = 0; kwl->kw[index].kw != NULL; index++) {
+			make_word_fingerprint(list_sig, kwl->kw[index].kw);
+			dist = word_fingerprint_distance(word_sig, list_sig);
+			if (dist < best_dist) {
+				best_dist = dist;
+				best_kw   = &kwl->kw[index];
+				best_ptr  = best_kw->kw;
+			}
+		}
+	}
+
+	while (extra && *extra) {
+		make_word_fingerprint(list_sig, *extra);
+		dist = word_fingerprint_distance(word_sig, list_sig);
+		if (dist < best_dist) {
+			best_dist = dist;
+			best_kw   = NULL;
+			best_ptr  = *extra;
+		}
+		extra++;
+	}
+
+	/* eliminate too different ones, with more tolerance for prefixes
+	 * when they're known to exist (not from extra list).
+	 */
+	if (best_ptr &&
+	    (best_dist > (2 + (best_kw && (best_kw->flags & KWF_MATCH_PREFIX))) * strlen(word) ||
+	     best_dist > (2 + (best_kw && (best_kw->flags & KWF_MATCH_PREFIX))) * strlen(best_ptr)))
+		best_ptr = NULL;
+
+	return best_ptr;
+}
+
+/* allocates a rule for ruleset <from> (ACT_F_*), from file name <file> and
+ * line <linenum>. <file> and <linenum> may be zero if unknown. Returns the
+ * rule, otherwise NULL in case of memory allocation error.
+ */
+struct act_rule *new_act_rule(enum act_from from, const char *file, int linenum)
+{
+	struct act_rule *rule;
+
+	rule = calloc(1, sizeof(*rule));
+	if (!rule)
+		return NULL;
+	rule->from = from;
+	rule->conf.file = file ? strdup(file) : NULL;
+	rule->conf.line = linenum;
+	LIST_INIT(&rule->list);
+	return rule;
+}
+
+/* fees rule <rule> and its elements as well as the condition */
+void free_act_rule(struct act_rule *rule)
+{
+	LIST_DELETE(&rule->list);
+	free_acl_cond(rule->cond);
+	if (rule->release_ptr)
+		rule->release_ptr(rule);
+	free(rule->conf.file);
+	free(rule);
+}
+
+void free_act_rules(struct list *rules)
+{
+	struct act_rule *rule, *ruleb;
+
+	list_for_each_entry_safe(rule, ruleb, rules, list) {
+		free_act_rule(rule);
+	}
+}
+
+/* dumps all known actions registered in action rules <rules> after prefix
+ * <pfx> to stdout. The actions are alphabetically sorted. Those with the
+ * KWF_MATCH_PREFIX flag have their name suffixed with '*'.
+ */
+void dump_act_rules(const struct list *rules, const char *pfx)
+{
+	const struct action_kw *akwp, *akwn;
+	struct action_kw_list *akwl;
+	int index;
+
+	for (akwn = akwp = NULL;; akwp = akwn) {
+		list_for_each_entry(akwl, rules, list) {
+			for (index = 0; akwl->kw[index].kw != NULL; index++)
+				if (strordered(akwp ? akwp->kw : NULL,
+					       akwl->kw[index].kw,
+					       akwn != akwp ? akwn->kw : NULL))
+					akwn = &akwl->kw[index];
+		}
+		if (akwn == akwp)
+			break;
+		printf("%s%s%s\n", pfx ? pfx : "", akwn->kw,
+		       (akwn->flags & KWF_MATCH_PREFIX) ? "*" : "");
+	}
+}