[PATCH iproute2 3/3] testsuite: add bond slave LACP port state test

[Dave Seddon <dave.seddon.ca@gmail.com>]

Decode generated RTM_NEWLINK messages with ip -d monitor file and
check the partner state value and flags, the u8 actor state, and
zero and absent partner attributes.

Use a synthetic 0x0100 partner state to detect a one-byte reader on
both endian types: it returns 0 on little-endian and 1 on big-endian
instead of 256. Real LACP states use only the low eight bits.

Check the actor state before asserting partner attribute absence,
so empty output cannot satisfy that test.

Assisted-by: LLM
Signed-off-by: Dave Seddon <dave.seddon.ca@gmail.com>
---
 .gitignore                                    |   1 +
 testsuite/Makefile                            |   1 +
 .../ip/link/show_bond_slave_lacp_state.t      |  33 ++++++
 testsuite/tools/generate_nlmsg.c              | 103 ++++++++++++++++--
 4 files changed, 129 insertions(+), 9 deletions(-)
 create mode 100755 testsuite/tests/ip/link/show_bond_slave_lacp_state.t

diff --git a/.gitignore b/.gitignore
index e5234a3d..a16f6362 100644
--- a/.gitignore
+++ b/.gitignore
@@ -39,3 +39,4 @@ testsuite/results
 testsuite/iproute2/iproute2-this
 testsuite/tools/generate_nlmsg
 testsuite/tests/ip/link/dev_wo_vf_rate.nl
+testsuite/tests/ip/link/bond_slave_partner_*.nl
diff --git a/testsuite/Makefile b/testsuite/Makefile
index fb50f618..bef66002 100644
--- a/testsuite/Makefile
+++ b/testsuite/Makefile
@@ -48,6 +48,7 @@ testclean:
 clean: testclean
 	@rm -f iproute2/iproute2-this
 	@rm -f tests/ip/link/dev_wo_vf_rate.nl
+	@rm -f tests/ip/link/bond_slave_partner_*.nl
 	$(MAKE) -C tools clean
 
 distclean: clean
diff --git a/testsuite/tests/ip/link/show_bond_slave_lacp_state.t b/testsuite/tests/ip/link/show_bond_slave_lacp_state.t
new file mode 100755
index 00000000..4ccf3960
--- /dev/null
+++ b/testsuite/tests/ip/link/show_bond_slave_lacp_state.t
@@ -0,0 +1,33 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+
+. lib/generic.sh
+
+# IFLA_BOND_SLAVE_AD_PARTNER_OPER_PORT_STATE is a u16 on the wire; the
+# actor state next to it is a u8. Each row decodes one blob written by
+# tools/generate_nlmsg and checks the printed value.
+#
+# The synthetic 0x0100 state checks the full attribute width on either
+# endian: a u8 reader returns 0 on little-endian and 1 on big-endian.
+#
+# row: file suffix | description | expected regex (!regex: must be absent)
+while IFS='|' read -r suffix desc expect; do
+	[ -z "$suffix" ] && continue
+	NL_FILE="tests/ip/link/bond_slave_partner_${suffix}.nl"
+	ts_ip "$0" "$desc" -d monitor file "$NL_FILE"
+	case "$expect" in
+	!*)
+		test_on "ad_actor_oper_port_state 63[^0-9]"
+		test_on_not "${expect#!}"
+		;;
+	*)
+		test_on "$expect"
+		;;
+	esac
+done <<EOF
+fast|partner state 0x3f|ad_partner_oper_port_state 63 ad_partner_oper_port_state_str <active,short_timeout,aggregating,in_sync,collecting,distributing>
+fast|actor state stays u8|ad_actor_oper_port_state 63[^0-9]
+zero|partner state 0|ad_partner_oper_port_state 0 ad_partner_oper_port_state_str <>
+hionly|partner state 0x0100, high byte only|ad_partner_oper_port_state 256[^0-9]
+absent|no partner attribute|!ad_partner_oper_port_state
+EOF
diff --git a/testsuite/tools/generate_nlmsg.c b/testsuite/tools/generate_nlmsg.c
index 106dca63..7c0aed3a 100644
--- a/testsuite/tools/generate_nlmsg.c
+++ b/testsuite/tools/generate_nlmsg.c
@@ -11,6 +11,9 @@
 #include <linux/if.h>
 #include <errno.h>
 #include <stdio.h>
+#include <string.h>
+#include <linux/if_link.h>
+#include "utils.h"
 
 int fill_vf_rate_test(void *buf, size_t buflen)
 {
@@ -40,6 +43,7 @@ int fill_vf_rate_test(void *buf, size_t buflen)
 #define ASSERT(x) if (x < 0) return -1
 #define ATTR_L(t, v, l)	ASSERT(addattr_l(h, buflen, t, v, l))
 #define ATTR_8(t, v)	ASSERT(addattr8(h, buflen, t, v))
+#define ATTR_16(t, v)	ASSERT(addattr16(h, buflen, t, v))
 #define ATTR_32(t, v)	ASSERT(addattr32(h, buflen, t, v))
 #define ATTR_STRZ(t, v)	ASSERT(addattrstrz(h, buflen, t, v))
 
@@ -87,26 +91,107 @@ int fill_vf_rate_test(void *buf, size_t buflen)
 	return h->nlmsg_len;
 }
 
+/* The synthetic 0x0100 state detects a u8 reader on either endian. */
+struct bond_slave_case {
+	const char *file;
+	__u16 partner_state;
+	bool has_partner;
+};
+
+static const struct bond_slave_case bond_slave_cases[] = {
+	{ "tests/ip/link/bond_slave_partner_fast.nl",	0x003f, true },
+	{ "tests/ip/link/bond_slave_partner_zero.nl",	0x0000, true },
+	{ "tests/ip/link/bond_slave_partner_hionly.nl",	0x0100, true },
+	{ "tests/ip/link/bond_slave_partner_absent.nl",	0x0000, false },
+};
+
+static int fill_bond_slave_test(void *buf, size_t buflen,
+				const struct bond_slave_case *c)
+{
+	__u8 mac[ETH_ALEN] = { 0x02, 0x00, 0x00, 0x00, 0x00, 0x01 };
+	struct rtattr *linkinfo, *slave_data;
+	struct nlmsghdr *h = buf;
+	struct ifinfomsg *ifi;
+
+	memset(buf, 0, buflen);
+	h->nlmsg_type = RTM_NEWLINK;
+	h->nlmsg_len = NLMSG_LENGTH(sizeof(*ifi));
+
+	ifi = NLMSG_DATA(h);
+	ifi->ifi_type = ARPHRD_ETHER;
+	ifi->ifi_index = 2;
+	ifi->ifi_flags = IFF_RUNNING | IFF_BROADCAST | IFF_MULTICAST |
+			 IFF_UP | IFF_LOWER_UP | IFF_SLAVE;
+
+	ATTR_STRZ(IFLA_IFNAME, "eth1");
+	ATTR_32(IFLA_MTU, 1500);
+	ATTR_L(IFLA_ADDRESS, mac, sizeof(mac));
+
+	linkinfo = NEST(IFLA_LINKINFO);
+	ATTR_STRZ(IFLA_INFO_SLAVE_KIND, "bond");
+	slave_data = NEST(IFLA_INFO_SLAVE_DATA);
+	ATTR_8(IFLA_BOND_SLAVE_STATE, 0);
+	ATTR_8(IFLA_BOND_SLAVE_MII_STATUS, 0);
+	ATTR_32(IFLA_BOND_SLAVE_LINK_FAILURE_COUNT, 0);
+	ATTR_L(IFLA_BOND_SLAVE_PERM_HWADDR, mac, sizeof(mac));
+	ATTR_16(IFLA_BOND_SLAVE_QUEUE_ID, 0);
+	ATTR_16(IFLA_BOND_SLAVE_AD_AGGREGATOR_ID, 1);
+	ATTR_8(IFLA_BOND_SLAVE_AD_ACTOR_OPER_PORT_STATE, 0x3f);
+	if (c->has_partner)
+		ATTR_16(IFLA_BOND_SLAVE_AD_PARTNER_OPER_PORT_STATE,
+			c->partner_state);
+	NEST_END(slave_data);
+	NEST_END(linkinfo);
+
+	return h->nlmsg_len;
+}
+
+static int write_nlmsg(const char *file, const void *buf, int msglen)
+{
+	FILE *fp;
+
+	fp = fopen(file, "wb");
+	if (!fp) {
+		perror("fopen()");
+		return -1;
+	}
+	if (fwrite(buf, msglen, 1, fp) != 1) {
+		perror("fwrite()");
+		fclose(fp);
+		return -1;
+	}
+	if (fclose(fp)) {
+		perror("fclose()");
+		return -1;
+	}
+	return 0;
+}
+
 int main(void)
 {
 	char buf[16384] = { 0 };
+	unsigned int i;
 	int msglen;
-	FILE *fp;
 
 	msglen = fill_vf_rate_test(buf, sizeof(buf));
 	if (msglen < 0) {
 		fprintf(stderr, "fill_vf_rate_test() failed!\n");
 		return 1;
 	}
-	fp = fopen("tests/ip/link/dev_wo_vf_rate.nl", "w");
-	if (!fp) {
-		perror("fopen()");
-		return 1;
-	}
-	if (fwrite(buf, msglen, 1, fp) != 1) {
-		perror("fwrite()");
+	if (write_nlmsg("tests/ip/link/dev_wo_vf_rate.nl", buf, msglen))
 		return 1;
+
+	for (i = 0; i < ARRAY_SIZE(bond_slave_cases); i++) {
+		const struct bond_slave_case *c = &bond_slave_cases[i];
+
+		msglen = fill_bond_slave_test(buf, sizeof(buf), c);
+		if (msglen < 0) {
+			fprintf(stderr, "fill_bond_slave_test(%s) failed!\n",
+				c->file);
+			return 1;
+		}
+		if (write_nlmsg(c->file, buf, msglen))
+			return 1;
 	}
-	fclose(fp);
 	return 0;
 }
-- 
2.55.0