* [PATCH v2 3/4] net: add VLAN insert function with a TPID argument
2026-08-26 17:38 [PATCH v2 1/4] net: fix VLAN insert doc comment for shared-mbuf error code William Bland
2026-08-26 17:38 ` [PATCH v2 2/4] net/af_packet: make Rx VLAN stripped flag handling explicit William Bland
@ 2026-08-26 17:38 ` William Bland
2026-08-26 20:27 ` Stephen Hemminger
2026-08-26 17:38 ` [PATCH v2 4/4] net/af_packet: fix QinQ outer TPID on VLAN reinsertion William Bland
2026-08-26 20:26 ` [PATCH v2 1/4] net: fix VLAN insert doc comment for shared-mbuf error code Stephen Hemminger
3 siblings, 1 reply; 7+ messages in thread
From: William Bland @ 2026-08-26 17:38 UTC (permalink / raw)
Cc: dev, William Bland
rte_vlan_insert() hardcodes EtherType 0x8100 (802.1Q). This is wrong
when reinserting a stripped tag whose original TPID was 0x88a8 (802.1ad
QinQ).
Add rte_vlan_insert_tpid() which takes an explicit tpid parameter, and
rewrite rte_vlan_insert() as a wrapper that passes RTE_ETHER_TYPE_VLAN.
Signed-off-by: William Bland <blandwwa@gmail.com>
---
app/test/meson.build | 2 +-
app/test/test_net_ether.c | 149 +++++++++++++++++++++++--
doc/guides/rel_notes/release_26_11.rst | 7 ++
lib/net/rte_ether.h | 61 +++++++---
4 files changed, 193 insertions(+), 26 deletions(-)
diff --git a/app/test/meson.build b/app/test/meson.build
index 51abeeb732..e927d4306a 100644
--- a/app/test/meson.build
+++ b/app/test/meson.build
@@ -134,7 +134,7 @@ source_file_deps = {
'test_meter.c': ['meter'],
'test_metrics.c': ['metrics'],
'test_mp_secondary.c': ['hash'],
- 'test_net_ether.c': ['net'],
+ 'test_net_ether.c': ['net', 'mbuf'],
'test_net_ip6.c': ['net'],
'test_pcapng.c': ['net_null', 'net', 'ethdev', 'pcapng', 'bus_vdev'],
'test_pdcp.c': ['eventdev', 'pdcp', 'net', 'timer', 'security'],
diff --git a/app/test/test_net_ether.c b/app/test/test_net_ether.c
index ec11224171..a1ead2eba8 100644
--- a/app/test/test_net_ether.c
+++ b/app/test/test_net_ether.c
@@ -3,6 +3,8 @@
*/
#include <rte_ether.h>
+#include <rte_mbuf.h>
+#include <rte_mempool.h>
#include <rte_test.h>
#include "test.h"
@@ -14,6 +16,8 @@ static const struct rte_ether_addr bcast_ea = {
.addr_bytes = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },
};
+static struct rte_mempool *net_ether_test_pool;
+
static int
test_ether_addr(void)
{
@@ -144,22 +148,147 @@ test_invalid_addr(void)
return 0;
}
+/*
+ * Build a minimal Ethernet frame in an mbuf: Ethernet header with the given
+ * ether_type followed by payload_len bytes of padding.
+ */
+static struct rte_mbuf *
+alloc_frame(struct rte_mempool *mp, uint16_t ether_type, uint16_t payload_len)
+{
+ struct rte_ether_hdr *eh;
+ struct rte_mbuf *m;
+
+ m = rte_pktmbuf_alloc(mp);
+ if (m == NULL)
+ return NULL;
+
+ eh = (struct rte_ether_hdr *)rte_pktmbuf_append(m,
+ sizeof(*eh) + payload_len);
+ if (eh == NULL) {
+ rte_pktmbuf_free(m);
+ return NULL;
+ }
+
+ memset(eh->dst_addr.addr_bytes, 0xff, RTE_ETHER_ADDR_LEN);
+ memset(eh->src_addr.addr_bytes, 0x00, RTE_ETHER_ADDR_LEN);
+ eh->ether_type = rte_cpu_to_be_16(ether_type);
+
+ return m;
+}
+
static int
-test_net_ether(void)
+test_vlan_insert_8021q(void)
{
- if (test_ether_addr())
- return -1;
+ struct rte_ether_hdr *eh;
+ struct rte_vlan_hdr *vh;
+ struct rte_mbuf *m;
+ int ret;
- if (test_format_addr())
- return -1;
+ m = alloc_frame(net_ether_test_pool, RTE_ETHER_TYPE_IPV4, 46);
+ TEST_ASSERT_NOT_NULL(m, "Failed to allocate mbuf");
- if (test_unformat_addr())
- return -1;
+ m->vlan_tci = 100;
+ m->ol_flags |= RTE_MBUF_F_RX_VLAN | RTE_MBUF_F_RX_VLAN_STRIPPED;
- if (test_invalid_addr())
- return -1;
+ ret = rte_vlan_insert(&m);
+ TEST_ASSERT_SUCCESS(ret, "rte_vlan_insert failed");
- return 0;
+ eh = rte_pktmbuf_mtod(m, struct rte_ether_hdr *);
+ TEST_ASSERT_EQUAL(rte_be_to_cpu_16(eh->ether_type), RTE_ETHER_TYPE_VLAN,
+ "Expected 802.1Q TPID 0x%04x, got 0x%04x",
+ RTE_ETHER_TYPE_VLAN, rte_be_to_cpu_16(eh->ether_type));
+
+ vh = (struct rte_vlan_hdr *)(eh + 1);
+ TEST_ASSERT_EQUAL(rte_be_to_cpu_16(vh->vlan_tci), 100,
+ "Expected VID 100, got %u", rte_be_to_cpu_16(vh->vlan_tci));
+
+ rte_pktmbuf_free(m);
+ return TEST_SUCCESS;
+}
+
+static int
+test_vlan_insert_tpid(void)
+{
+ struct rte_ether_hdr *eh;
+ struct rte_vlan_hdr *vh;
+ struct rte_mbuf *m;
+ int ret;
+
+ m = alloc_frame(net_ether_test_pool, RTE_ETHER_TYPE_VLAN, sizeof(*vh) + 46);
+ TEST_ASSERT_NOT_NULL(m, "Failed to allocate mbuf");
+
+ vh = (struct rte_vlan_hdr *)(rte_pktmbuf_mtod(m, struct rte_ether_hdr *) + 1);
+ vh->vlan_tci = rte_cpu_to_be_16(200);
+ vh->eth_proto = rte_cpu_to_be_16(RTE_ETHER_TYPE_IPV4);
+
+ m->vlan_tci = 50;
+ m->ol_flags |= RTE_MBUF_F_RX_VLAN | RTE_MBUF_F_RX_VLAN_STRIPPED;
+
+ ret = rte_vlan_insert_tpid(&m, RTE_ETHER_TYPE_QINQ);
+ TEST_ASSERT_SUCCESS(ret, "rte_vlan_insert_tpid failed");
+
+ eh = rte_pktmbuf_mtod(m, struct rte_ether_hdr *);
+
+ TEST_ASSERT_EQUAL(rte_be_to_cpu_16(eh->ether_type), RTE_ETHER_TYPE_QINQ,
+ "Outer TPID: expected 0x%04x (802.1ad) got 0x%04x",
+ RTE_ETHER_TYPE_QINQ, rte_be_to_cpu_16(eh->ether_type));
+
+ vh = (struct rte_vlan_hdr *)(eh + 1);
+ TEST_ASSERT_EQUAL(rte_be_to_cpu_16(vh->vlan_tci), 50,
+ "Outer VID: expected 50, got %u",
+ rte_be_to_cpu_16(vh->vlan_tci));
+ TEST_ASSERT_EQUAL(rte_be_to_cpu_16(vh->eth_proto), RTE_ETHER_TYPE_VLAN,
+ "Outer eth_proto: expected 0x%04x (802.1Q), got 0x%04x",
+ RTE_ETHER_TYPE_VLAN, rte_be_to_cpu_16(vh->eth_proto));
+
+ vh = vh + 1;
+ TEST_ASSERT_EQUAL(rte_be_to_cpu_16(vh->vlan_tci), 200,
+ "Inner VID: expected 200, got %u",
+ rte_be_to_cpu_16(vh->vlan_tci));
+ TEST_ASSERT_EQUAL(rte_be_to_cpu_16(vh->eth_proto), RTE_ETHER_TYPE_IPV4,
+ "Inner eth_proto: expected 0x%04x (IPv4), got 0x%04x",
+ RTE_ETHER_TYPE_IPV4, rte_be_to_cpu_16(vh->eth_proto));
+
+ rte_pktmbuf_free(m);
+ return TEST_SUCCESS;
+}
+
+static int
+net_ether_testsuite_setup(void)
+{
+ net_ether_test_pool = rte_pktmbuf_pool_create("net_ether_test_pool", 64, 0, 0,
+ RTE_MBUF_DEFAULT_BUF_SIZE, SOCKET_ID_ANY);
+ TEST_ASSERT_NOT_NULL(net_ether_test_pool, "Failed to create mempool");
+
+ return TEST_SUCCESS;
+}
+
+static void
+net_ether_testsuite_teardown(void)
+{
+ rte_mempool_free(net_ether_test_pool);
+ net_ether_test_pool = NULL;
+}
+
+static struct unit_test_suite net_ether_testsuite = {
+ .suite_name = "net_ether autotest",
+ .setup = net_ether_testsuite_setup,
+ .teardown = net_ether_testsuite_teardown,
+ .unit_test_cases = {
+ TEST_CASE(test_ether_addr),
+ TEST_CASE(test_format_addr),
+ TEST_CASE(test_unformat_addr),
+ TEST_CASE(test_invalid_addr),
+ TEST_CASE(test_vlan_insert_8021q),
+ TEST_CASE(test_vlan_insert_tpid),
+ TEST_CASES_END()
+ }
+};
+
+static int
+test_net_ether(void)
+{
+ return unit_test_suite_runner(&net_ether_testsuite);
}
REGISTER_FAST_TEST(net_ether_autotest, NOHUGE_OK, ASAN_OK, test_net_ether);
diff --git a/doc/guides/rel_notes/release_26_11.rst b/doc/guides/rel_notes/release_26_11.rst
index c8cc86295d..a7481b51ff 100644
--- a/doc/guides/rel_notes/release_26_11.rst
+++ b/doc/guides/rel_notes/release_26_11.rst
@@ -55,6 +55,13 @@ New Features
Also, make sure to start the actual text at the margin.
=======================================================
+* **Added TPID support to VLAN tag insertion.**
+
+ Added ``rte_vlan_insert_tpid()`` to the net library, allowing the Tag
+ Protocol Identifier (TPID) of an inserted VLAN tag to be specified
+ explicitly, so that 802.1ad (QinQ) outer tags can be reinserted with
+ the correct EtherType.
+
Removed Items
-------------
diff --git a/lib/net/rte_ether.h b/lib/net/rte_ether.h
index cb10d8fb06..23c4806cc5 100644
--- a/lib/net/rte_ether.h
+++ b/lib/net/rte_ether.h
@@ -378,20 +378,7 @@ static inline int rte_vlan_strip(struct rte_mbuf *m)
return 0;
}
-/**
- * Insert VLAN tag into mbuf.
- *
- * Software version of VLAN unstripping
- *
- * @param m
- * The packet mbuf.
- * @return
- * - 0: On success
- * -EINVAL: overwriting would be unsafe because mbuf is shared or
- * indirect, or mbuf's first segment is too short
- * -ENOSPC: not enough headroom in mbuf
- */
-static inline int rte_vlan_insert(struct rte_mbuf **m)
+static inline int __rte_vlan_insert(struct rte_mbuf **m, uint16_t tpid)
{
struct rte_ether_hdr *oh, *nh;
struct rte_vlan_hdr *vh;
@@ -411,7 +398,7 @@ static inline int rte_vlan_insert(struct rte_mbuf **m)
return -ENOSPC;
memmove(nh, oh, 2 * RTE_ETHER_ADDR_LEN);
- nh->ether_type = rte_cpu_to_be_16(RTE_ETHER_TYPE_VLAN);
+ nh->ether_type = rte_cpu_to_be_16(tpid);
vh = (struct rte_vlan_hdr *) (nh + 1);
vh->vlan_tci = rte_cpu_to_be_16((*m)->vlan_tci);
@@ -426,6 +413,50 @@ static inline int rte_vlan_insert(struct rte_mbuf **m)
return 0;
}
+/**
+ * Insert VLAN tag into mbuf.
+ *
+ * Software version of VLAN unstripping. Always inserts an 802.1Q tag
+ * (TPID 0x8100). Use rte_vlan_insert_tpid() when the original TPID may
+ * differ (e.g. 802.1ad QinQ outer tags).
+ *
+ * @param m
+ * The packet mbuf.
+ * @return
+ * - 0: On success
+ * -EINVAL: overwriting would be unsafe because mbuf is shared or
+ * indirect, or mbuf's first segment is too short
+ * -ENOSPC: not enough headroom in mbuf
+ */
+static inline int rte_vlan_insert(struct rte_mbuf **m)
+{
+ return __rte_vlan_insert(m, RTE_ETHER_TYPE_VLAN);
+}
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Insert VLAN tag with the given TPID into mbuf.
+ *
+ * Software version of VLAN unstripping.
+ *
+ * @param m
+ * The packet mbuf.
+ * @param tpid
+ * Tag Protocol Identifier to insert (host order).
+ * @return
+ * - 0: On success
+ * -EINVAL: overwriting would be unsafe because mbuf is shared or
+ * indirect, or mbuf's first segment is too short
+ * -ENOSPC: not enough headroom in mbuf
+ */
+__rte_experimental
+static inline int rte_vlan_insert_tpid(struct rte_mbuf **m, uint16_t tpid)
+{
+ return __rte_vlan_insert(m, tpid);
+}
+
#ifdef __cplusplus
}
#endif
--
2.43.0
^ permalink raw reply related [flat|nested] 7+ messages in thread