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From: numans@ovn.org
To: dev@openvswitch.org
Date: Thu, 12 Nov 2020 17:26:57 +0530
Message-Id: <20201112115657.1362356-1-numans@ovn.org>
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Subject: [ovs-dev] [PATCH ovn v4 4/7] actions: Add new actions
chk_lb_hairpin, chk_lb_hairpin_reply and ct_snat_to_vip.
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From: Numan Siddique
The action - chk_lb_hairpin checks if the packet destined to a load balancer VIP
is to be hairpinned back to the same destination and if so, sets the destination register
bit to 1.
The action - chk_lb_hairpin_reply checks if the packet is a reply of the hairpinned
packet. If so, it sets the destination register bit to 1.
The action ct_snat_to_vip snats the source IP to the load balancer VIP if chk_lb_hairpin()
returned true.
These actions will be used in the upcoming patch by ovn-northd in the hairpin logical flows.
This helps in reducing lots of hairpin logical flows.
Signed-off-by: Numan Siddique
---
controller/lflow.c | 3 ++
include/ovn/actions.h | 15 ++++--
lib/actions.c | 116 ++++++++++++++++++++++++++++++++++++++----
ovn-sb.xml | 37 ++++++++++++++
tests/ovn.at | 39 ++++++++++++++
tests/test-ovn.c | 3 ++
utilities/ovn-trace.c | 65 ++++++++++++++++++++++-
7 files changed, 265 insertions(+), 13 deletions(-)
diff --git a/controller/lflow.c b/controller/lflow.c
index 30113295d9..4b34564d05 100644
--- a/controller/lflow.c
+++ b/controller/lflow.c
@@ -698,6 +698,9 @@ add_matches_to_flow_table(const struct sbrec_logical_flow *lflow,
.output_ptable = output_ptable,
.mac_bind_ptable = OFTABLE_MAC_BINDING,
.mac_lookup_ptable = OFTABLE_MAC_LOOKUP,
+ .lb_hairpin_ptable = OFTABLE_CHK_LB_HAIRPIN,
+ .lb_hairpin_reply_ptable = OFTABLE_CHK_LB_HAIRPIN_REPLY,
+ .ct_snat_vip_ptable = OFTABLE_CT_SNAT_FOR_VIP,
};
ovnacts_encode(ovnacts->data, ovnacts->size, &ep, &ofpacts);
diff --git a/include/ovn/actions.h b/include/ovn/actions.h
index b4e5acabb9..630bbe79e4 100644
--- a/include/ovn/actions.h
+++ b/include/ovn/actions.h
@@ -83,7 +83,7 @@ struct ovn_extend_table;
OVNACT(PUT_DHCPV4_OPTS, ovnact_put_opts) \
OVNACT(PUT_DHCPV6_OPTS, ovnact_put_opts) \
OVNACT(SET_QUEUE, ovnact_set_queue) \
- OVNACT(DNS_LOOKUP, ovnact_dns_lookup) \
+ OVNACT(DNS_LOOKUP, ovnact_result) \
OVNACT(LOG, ovnact_log) \
OVNACT(PUT_ND_RA_OPTS, ovnact_put_opts) \
OVNACT(ND_NS, ovnact_nest) \
@@ -97,6 +97,9 @@ struct ovn_extend_table;
OVNACT(DHCP6_REPLY, ovnact_null) \
OVNACT(ICMP6_ERROR, ovnact_nest) \
OVNACT(REJECT, ovnact_nest) \
+ OVNACT(CHK_LB_HAIRPIN, ovnact_result) \
+ OVNACT(CHK_LB_HAIRPIN_REPLY, ovnact_result) \
+ OVNACT(CT_SNAT_TO_VIP, ovnact_null) \
/* enum ovnact_type, with a member OVNACT_ for each action. */
enum OVS_PACKED_ENUM ovnact_type {
@@ -338,8 +341,8 @@ struct ovnact_set_queue {
uint16_t queue_id;
};
-/* OVNACT_DNS_LOOKUP. */
-struct ovnact_dns_lookup {
+/* OVNACT_DNS_LOOKUP, OVNACT_CHK_LB_HAIRPIN, OVNACT_CHK_LB_HAIRPIN_REPLY. */
+struct ovnact_result {
struct ovnact ovnact;
struct expr_field dst; /* 1-bit destination field. */
};
@@ -727,6 +730,12 @@ struct ovnact_encode_params {
resubmit. */
uint8_t mac_lookup_ptable; /* OpenFlow table for
'lookup_arp'/'lookup_nd' to resubmit. */
+ uint8_t lb_hairpin_ptable; /* OpenFlow table for
+ * 'chk_lb_hairpin' to resubmit. */
+ uint8_t lb_hairpin_reply_ptable; /* OpenFlow table for
+ * 'chk_lb_hairpin_reply' to resubmit. */
+ uint8_t ct_snat_vip_ptable; /* OpenFlow table for
+ * 'ct_snat_to_vip' to resubmit. */
};
void ovnacts_encode(const struct ovnact[], size_t ovnacts_len,
diff --git a/lib/actions.c b/lib/actions.c
index 6300fef2c4..82b35ccf9b 100644
--- a/lib/actions.c
+++ b/lib/actions.c
@@ -2655,13 +2655,14 @@ ovnact_set_queue_free(struct ovnact_set_queue *a OVS_UNUSED)
}
static void
-parse_dns_lookup(struct action_context *ctx, const struct expr_field *dst,
- struct ovnact_dns_lookup *dl)
+parse_ovnact_result(struct action_context *ctx, const char *name,
+ const char *prereq, const struct expr_field *dst,
+ struct ovnact_result *res)
{
- lexer_get(ctx->lexer); /* Skip dns_lookup. */
+ lexer_get(ctx->lexer); /* Skip action name. */
lexer_get(ctx->lexer); /* Skip '('. */
if (!lexer_match(ctx->lexer, LEX_T_RPAREN)) {
- lexer_error(ctx->lexer, "dns_lookup doesn't take any parameters");
+ lexer_error(ctx->lexer, "%s doesn't take any parameters", name);
return;
}
/* Validate that the destination is a 1-bit, modifiable field. */
@@ -2671,19 +2672,29 @@ parse_dns_lookup(struct action_context *ctx, const struct expr_field *dst,
free(error);
return;
}
- dl->dst = *dst;
- add_prerequisite(ctx, "udp");
+ res->dst = *dst;
+
+ if (prereq) {
+ add_prerequisite(ctx, prereq);
+ }
}
static void
-format_DNS_LOOKUP(const struct ovnact_dns_lookup *dl, struct ds *s)
+parse_dns_lookup(struct action_context *ctx, const struct expr_field *dst,
+ struct ovnact_result *dl)
+{
+ parse_ovnact_result(ctx, "dns_lookup", "udp", dst, dl);
+}
+
+static void
+format_DNS_LOOKUP(const struct ovnact_result *dl, struct ds *s)
{
expr_field_format(&dl->dst, s);
ds_put_cstr(s, " = dns_lookup();");
}
static void
-encode_DNS_LOOKUP(const struct ovnact_dns_lookup *dl,
+encode_DNS_LOOKUP(const struct ovnact_result *dl,
const struct ovnact_encode_params *ep OVS_UNUSED,
struct ofpbuf *ofpacts)
{
@@ -2700,7 +2711,7 @@ encode_DNS_LOOKUP(const struct ovnact_dns_lookup *dl,
static void
-ovnact_dns_lookup_free(struct ovnact_dns_lookup *dl OVS_UNUSED)
+ovnact_result_free(struct ovnact_result *dl OVS_UNUSED)
{
}
@@ -3474,6 +3485,83 @@ ovnact_fwd_group_free(struct ovnact_fwd_group *fwd_group)
free(fwd_group->child_ports);
}
+static void
+parse_chk_lb_hairpin(struct action_context *ctx, const struct expr_field *dst,
+ struct ovnact_result *res)
+{
+ parse_ovnact_result(ctx, "chk_lb_hairpin", NULL, dst, res);
+}
+
+static void
+parse_chk_lb_hairpin_reply(struct action_context *ctx,
+ const struct expr_field *dst,
+ struct ovnact_result *res)
+{
+ parse_ovnact_result(ctx, "chk_lb_hairpin_reply", NULL, dst, res);
+}
+
+
+static void
+format_CHK_LB_HAIRPIN(const struct ovnact_result *res, struct ds *s)
+{
+ expr_field_format(&res->dst, s);
+ ds_put_cstr(s, " = chk_lb_hairpin();");
+}
+
+static void
+format_CHK_LB_HAIRPIN_REPLY(const struct ovnact_result *res, struct ds *s)
+{
+ expr_field_format(&res->dst, s);
+ ds_put_cstr(s, " = chk_lb_hairpin_reply();");
+}
+
+static void
+encode_chk_lb_hairpin__(const struct ovnact_result *res,
+ uint8_t hairpin_table,
+ struct ofpbuf *ofpacts)
+{
+ struct mf_subfield dst = expr_resolve_field(&res->dst);
+ ovs_assert(dst.field);
+ put_load(0, MFF_LOG_FLAGS, MLF_LOOKUP_LB_HAIRPIN_BIT, 1, ofpacts);
+ emit_resubmit(ofpacts, hairpin_table);
+
+ struct ofpact_reg_move *orm = ofpact_put_REG_MOVE(ofpacts);
+ orm->dst = dst;
+ orm->src.field = mf_from_id(MFF_LOG_FLAGS);
+ orm->src.ofs = MLF_LOOKUP_LB_HAIRPIN_BIT;
+ orm->src.n_bits = 1;
+}
+
+static void
+encode_CHK_LB_HAIRPIN(const struct ovnact_result *res,
+ const struct ovnact_encode_params *ep,
+ struct ofpbuf *ofpacts)
+{
+ encode_chk_lb_hairpin__(res, ep->lb_hairpin_ptable, ofpacts);
+}
+
+static void
+encode_CHK_LB_HAIRPIN_REPLY(const struct ovnact_result *res,
+ const struct ovnact_encode_params *ep,
+ struct ofpbuf *ofpacts)
+{
+ encode_chk_lb_hairpin__(res, ep->lb_hairpin_reply_ptable, ofpacts);
+}
+
+static void
+format_CT_SNAT_TO_VIP(const struct ovnact_null *null OVS_UNUSED, struct ds *s)
+{
+ ds_put_cstr(s, "ct_snat_to_vip;");
+}
+
+static void
+encode_CT_SNAT_TO_VIP(const struct ovnact_null *null OVS_UNUSED,
+ const struct ovnact_encode_params *ep,
+ struct ofpbuf *ofpacts)
+{
+ emit_resubmit(ofpacts, ep->ct_snat_vip_ptable);
+}
+
/* Parses an assignment or exchange or put_dhcp_opts action. */
static void
parse_set_action(struct action_context *ctx)
@@ -3526,6 +3614,14 @@ parse_set_action(struct action_context *ctx)
&& lexer_lookahead(ctx->lexer) == LEX_T_LPAREN) {
parse_lookup_mac_bind_ip(ctx, &lhs, 128,
ovnact_put_LOOKUP_ND_IP(ctx->ovnacts));
+ } else if (!strcmp(ctx->lexer->token.s, "chk_lb_hairpin")
+ && lexer_lookahead(ctx->lexer) == LEX_T_LPAREN) {
+ parse_chk_lb_hairpin(ctx, &lhs,
+ ovnact_put_CHK_LB_HAIRPIN(ctx->ovnacts));
+ } else if (!strcmp(ctx->lexer->token.s, "chk_lb_hairpin_reply")
+ && lexer_lookahead(ctx->lexer) == LEX_T_LPAREN) {
+ parse_chk_lb_hairpin_reply(
+ ctx, &lhs, ovnact_put_CHK_LB_HAIRPIN_REPLY(ctx->ovnacts));
} else {
parse_assignment_action(ctx, false, &lhs);
}
@@ -3612,6 +3708,8 @@ parse_action(struct action_context *ctx)
ovnact_put_DHCP6_REPLY(ctx->ovnacts);
} else if (lexer_match_id(ctx->lexer, "reject")) {
parse_REJECT(ctx);
+ } else if (lexer_match_id(ctx->lexer, "ct_snat_to_vip")) {
+ ovnact_put_CT_SNAT_TO_VIP(ctx->ovnacts);
} else {
lexer_syntax_error(ctx->lexer, "expecting action");
}
diff --git a/ovn-sb.xml b/ovn-sb.xml
index b8fd7e873b..4c6df3fef5 100644
--- a/ovn-sb.xml
+++ b/ovn-sb.xml
@@ -2328,6 +2328,43 @@ tcp.flags = RST;
Delegation Router and managed IPv6 Prefix delegation state machine
+
+ R = chk_lb_hairpin();
+
+
+ This action checks if the packet under consideration was destined
+ to a load balancer VIP and it is hairpinned, i.e., after load
+ balancing the destination IP matches the source IP. If it is so,
+ then the 1-bit destination register R is set to 1.
+
+
+
+ R = chk_lb_hairpin_reply();
+
+
+ This action checks if the packet under consideration is from
+ one of the backend IP of a load balancer VIP and the destination IP
+ is the load balancer VIP. If it is so, then the 1-bit destination
+ register R is set to 1.
+
+
+
+ R = ct_snat_to_vip;
+
+
+ This action sends the packet through the SNAT zone to change the
+ source IP address of the packet to the load balancer VIP if the
+ original destination IP was load balancer VIP and commits the
+ connection. This action applies successfully only for the
+ hairpinned traffic i.e if the action chk_lb_hairpin
+ returned success. This action doesn't take any arguments and it
+ determines the SNAT IP internally.
+
+ The packet is not automatically sent to the next table. The caller
+ has to execute the next;
action explicitly after this
+ action to advance the packet to the next stage.
+
+
diff --git a/tests/ovn.at b/tests/ovn.at
index db2cb1b2f8..19d9a3cf6a 100644
--- a/tests/ovn.at
+++ b/tests/ovn.at
@@ -1724,6 +1724,45 @@ fwd_group(liveness=false childports="eth0", "lsp1");
handle_dhcpv6_reply;
encodes as controller(userdata=00.00.00.13.00.00.00.00)
+# chk_lb_hairpin
+reg0[0] = chk_lb_hairpin();
+ encodes as set_field:0/0x80->reg10,resubmit(,68),move:NXM_NX_REG10[7]->NXM_NX_XXREG0[96]
+
+reg2[2] = chk_lb_hairpin();
+ encodes as set_field:0/0x80->reg10,resubmit(,68),move:NXM_NX_REG10[7]->NXM_NX_XXREG0[34]
+
+reg0 = chk_lb_hairpin();
+ Cannot use 32-bit field reg0[0..31] where 1-bit field is required.
+
+reg0[0] = chk_lb_hairpin(foo);
+ chk_lb_hairpin doesn't take any parameters
+
+chk_lb_hairpin;
+ Syntax error at `chk_lb_hairpin' expecting action.
+
+# chk_lb_hairpin_reply
+reg0[0] = chk_lb_hairpin_reply();
+ encodes as set_field:0/0x80->reg10,resubmit(,69),move:NXM_NX_REG10[7]->NXM_NX_XXREG0[96]
+
+reg2[2..3] = chk_lb_hairpin_reply();
+ Cannot use 2-bit field reg2[2..3] where 1-bit field is required.
+
+reg0 = chk_lb_hairpin_reply();
+ Cannot use 32-bit field reg0[0..31] where 1-bit field is required.
+
+reg0[0] = chk_lb_hairpin_reply(foo);
+ chk_lb_hairpin_reply doesn't take any parameters
+
+chk_lb_hairpin_reply;
+ Syntax error at `chk_lb_hairpin_reply' expecting action.
+
+# ct_snat_to_vip
+ct_snat_to_vip;
+ encodes as resubmit(,70)
+
+ct_snat_to_vip(foo);
+ Syntax error at `(' expecting `;'.
+
# Miscellaneous negative tests.
;
Syntax error at `;'.
diff --git a/tests/test-ovn.c b/tests/test-ovn.c
index 74b5a3384d..b1e3ee43b7 100644
--- a/tests/test-ovn.c
+++ b/tests/test-ovn.c
@@ -1343,6 +1343,9 @@ test_parse_actions(struct ovs_cmdl_context *ctx OVS_UNUSED)
.output_ptable = OFTABLE_SAVE_INPORT,
.mac_bind_ptable = OFTABLE_MAC_BINDING,
.mac_lookup_ptable = OFTABLE_MAC_LOOKUP,
+ .lb_hairpin_ptable = OFTABLE_CHK_LB_HAIRPIN,
+ .lb_hairpin_reply_ptable = OFTABLE_CHK_LB_HAIRPIN_REPLY,
+ .ct_snat_vip_ptable = OFTABLE_CT_SNAT_FOR_VIP,
};
struct ofpbuf ofpacts;
ofpbuf_init(&ofpacts, 0);
diff --git a/utilities/ovn-trace.c b/utilities/ovn-trace.c
index 29bf7a2084..5d92188ab2 100644
--- a/utilities/ovn-trace.c
+++ b/utilities/ovn-trace.c
@@ -1992,7 +1992,7 @@ execute_next(const struct ovnact_next *next,
static void
-execute_dns_lookup(const struct ovnact_dns_lookup *dl, struct flow *uflow,
+execute_dns_lookup(const struct ovnact_result *dl, struct flow *uflow,
struct ovs_list *super)
{
struct mf_subfield sf = expr_resolve_field(&dl->dst);
@@ -2224,6 +2224,57 @@ execute_ovnfield_load(const struct ovnact_load *load,
}
}
+static void
+execute_chk_lb_hairpin(const struct ovnact_result *dl, struct flow *uflow,
+ struct ovs_list *super)
+{
+ int family = (uflow->dl_type == htons(ETH_TYPE_IP) ? AF_INET
+ : uflow->dl_type == htons(ETH_TYPE_IPV6) ? AF_INET6
+ : AF_UNSPEC);
+ uint8_t res = 0;
+ if (family != AF_UNSPEC && uflow->ct_state & CS_DST_NAT) {
+ if (family == AF_INET) {
+ res = (uflow->nw_src == uflow->nw_dst) ? 1 : 0;
+ } else {
+ res = ipv6_addr_equals(&uflow->ipv6_src, &uflow->ipv6_dst) ? 1 : 0;
+ }
+ }
+
+ struct mf_subfield sf = expr_resolve_field(&dl->dst);
+ union mf_subvalue sv = { .u8_val = res };
+ mf_write_subfield_flow(&sf, &sv, uflow);
+
+ struct ds s = DS_EMPTY_INITIALIZER;
+ expr_field_format(&dl->dst, &s);
+ ovntrace_node_append(super, OVNTRACE_NODE_MODIFY,
+ "%s = %d", ds_cstr(&s), res);
+ ds_destroy(&s);
+}
+
+static void
+execute_chk_lb_hairpin_reply(const struct ovnact_result *dl,
+ struct flow *uflow,
+ struct ovs_list *super)
+{
+ struct mf_subfield sf = expr_resolve_field(&dl->dst);
+ union mf_subvalue sv = { .u8_val = 0 };
+ mf_write_subfield_flow(&sf, &sv, uflow);
+ ovntrace_node_append(super, OVNTRACE_NODE_ERROR,
+ "*** chk_lb_hairpin_reply action not implemented");
+ struct ds s = DS_EMPTY_INITIALIZER;
+ expr_field_format(&dl->dst, &s);
+ ovntrace_node_append(super, OVNTRACE_NODE_MODIFY,
+ "%s = 0", ds_cstr(&s));
+ ds_destroy(&s);
+}
+
+static void
+execute_ct_snat_to_vip(struct flow *uflow OVS_UNUSED, struct ovs_list *super)
+{
+ ovntrace_node_append(super, OVNTRACE_NODE_ERROR,
+ "*** ct_snat_to_vip action not implemented");
+}
+
static void
trace_actions(const struct ovnact *ovnacts, size_t ovnacts_len,
const struct ovntrace_datapath *dp, struct flow *uflow,
@@ -2440,6 +2491,18 @@ trace_actions(const struct ovnact *ovnacts, size_t ovnacts_len,
pipeline, super);
break;
+ case OVNACT_CHK_LB_HAIRPIN:
+ execute_chk_lb_hairpin(ovnact_get_CHK_LB_HAIRPIN(a), uflow, super);
+ break;
+
+ case OVNACT_CHK_LB_HAIRPIN_REPLY:
+ execute_chk_lb_hairpin_reply(ovnact_get_CHK_LB_HAIRPIN_REPLY(a),
+ uflow, super);
+ break;
+ case OVNACT_CT_SNAT_TO_VIP:
+ execute_ct_snat_to_vip(uflow, super);
+ break;
+
case OVNACT_TRIGGER_EVENT:
break;