Adding upstream version 4.19.249.upstream/4.19.249upstream

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

1 files changed, 804 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/test_lpm_map.c b/tools/testing/selftests/bpf/test_lpm_map.c
new file mode 100644
index 000000000..006be3963
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_lpm_map.c
@@ -0,0 +1,804 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Randomized tests for eBPF longest-prefix-match maps
+ *
+ * This program runs randomized tests against the lpm-bpf-map. It implements a
+ * "Trivial Longest Prefix Match" (tlpm) based on simple, linear, singly linked
+ * lists. The implementation should be pretty straightforward.
+ *
+ * Based on tlpm, this inserts randomized data into bpf-lpm-maps and verifies
+ * the trie-based bpf-map implementation behaves the same way as tlpm.
+ */
+
+#include <assert.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <linux/bpf.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <arpa/inet.h>
+#include <sys/time.h>
+
+#include <bpf/bpf.h>
+
+#include "bpf_util.h"
+#include "bpf_rlimit.h"
+
+struct tlpm_node {
+	struct tlpm_node *next;
+	size_t n_bits;
+	uint8_t key[];
+};
+
+static struct tlpm_node *tlpm_match(struct tlpm_node *list,
+				    const uint8_t *key,
+				    size_t n_bits);
+
+static struct tlpm_node *tlpm_add(struct tlpm_node *list,
+				  const uint8_t *key,
+				  size_t n_bits)
+{
+	struct tlpm_node *node;
+	size_t n;
+
+	n = (n_bits + 7) / 8;
+
+	/* 'overwrite' an equivalent entry if one already exists */
+	node = tlpm_match(list, key, n_bits);
+	if (node && node->n_bits == n_bits) {
+		memcpy(node->key, key, n);
+		return list;
+	}
+
+	/* add new entry with @key/@n_bits to @list and return new head */
+
+	node = malloc(sizeof(*node) + n);
+	assert(node);
+
+	node->next = list;
+	node->n_bits = n_bits;
+	memcpy(node->key, key, n);
+
+	return node;
+}
+
+static void tlpm_clear(struct tlpm_node *list)
+{
+	struct tlpm_node *node;
+
+	/* free all entries in @list */
+
+	while ((node = list)) {
+		list = list->next;
+		free(node);
+	}
+}
+
+static struct tlpm_node *tlpm_match(struct tlpm_node *list,
+				    const uint8_t *key,
+				    size_t n_bits)
+{
+	struct tlpm_node *best = NULL;
+	size_t i;
+
+	/* Perform longest prefix-match on @key/@n_bits. That is, iterate all
+	 * entries and match each prefix against @key. Remember the "best"
+	 * entry we find (i.e., the longest prefix that matches) and return it
+	 * to the caller when done.
+	 */
+
+	for ( ; list; list = list->next) {
+		for (i = 0; i < n_bits && i < list->n_bits; ++i) {
+			if ((key[i / 8] & (1 << (7 - i % 8))) !=
+			    (list->key[i / 8] & (1 << (7 - i % 8))))
+				break;
+		}
+
+		if (i >= list->n_bits) {
+			if (!best || i > best->n_bits)
+				best = list;
+		}
+	}
+
+	return best;
+}
+
+static struct tlpm_node *tlpm_delete(struct tlpm_node *list,
+				     const uint8_t *key,
+				     size_t n_bits)
+{
+	struct tlpm_node *best = tlpm_match(list, key, n_bits);
+	struct tlpm_node *node;
+
+	if (!best || best->n_bits != n_bits)
+		return list;
+
+	if (best == list) {
+		node = best->next;
+		free(best);
+		return node;
+	}
+
+	for (node = list; node; node = node->next) {
+		if (node->next == best) {
+			node->next = best->next;
+			free(best);
+			return list;
+		}
+	}
+	/* should never get here */
+	assert(0);
+	return list;
+}
+
+static void test_lpm_basic(void)
+{
+	struct tlpm_node *list = NULL, *t1, *t2;
+
+	/* very basic, static tests to verify tlpm works as expected */
+
+	assert(!tlpm_match(list, (uint8_t[]){ 0xff }, 8));
+
+	t1 = list = tlpm_add(list, (uint8_t[]){ 0xff }, 8);
+	assert(t1 == tlpm_match(list, (uint8_t[]){ 0xff }, 8));
+	assert(t1 == tlpm_match(list, (uint8_t[]){ 0xff, 0xff }, 16));
+	assert(t1 == tlpm_match(list, (uint8_t[]){ 0xff, 0x00 }, 16));
+	assert(!tlpm_match(list, (uint8_t[]){ 0x7f }, 8));
+	assert(!tlpm_match(list, (uint8_t[]){ 0xfe }, 8));
+	assert(!tlpm_match(list, (uint8_t[]){ 0xff }, 7));
+
+	t2 = list = tlpm_add(list, (uint8_t[]){ 0xff, 0xff }, 16);
+	assert(t1 == tlpm_match(list, (uint8_t[]){ 0xff }, 8));
+	assert(t2 == tlpm_match(list, (uint8_t[]){ 0xff, 0xff }, 16));
+	assert(t1 == tlpm_match(list, (uint8_t[]){ 0xff, 0xff }, 15));
+	assert(!tlpm_match(list, (uint8_t[]){ 0x7f, 0xff }, 16));
+
+	list = tlpm_delete(list, (uint8_t[]){ 0xff, 0xff }, 16);
+	assert(t1 == tlpm_match(list, (uint8_t[]){ 0xff }, 8));
+	assert(t1 == tlpm_match(list, (uint8_t[]){ 0xff, 0xff }, 16));
+
+	list = tlpm_delete(list, (uint8_t[]){ 0xff }, 8);
+	assert(!tlpm_match(list, (uint8_t[]){ 0xff }, 8));
+
+	tlpm_clear(list);
+}
+
+static void test_lpm_order(void)
+{
+	struct tlpm_node *t1, *t2, *l1 = NULL, *l2 = NULL;
+	size_t i, j;
+
+	/* Verify the tlpm implementation works correctly regardless of the
+	 * order of entries. Insert a random set of entries into @l1, and copy
+	 * the same data in reverse order into @l2. Then verify a lookup of
+	 * random keys will yield the same result in both sets.
+	 */
+
+	for (i = 0; i < (1 << 12); ++i)
+		l1 = tlpm_add(l1, (uint8_t[]){
+					rand() % 0xff,
+					rand() % 0xff,
+				}, rand() % 16 + 1);
+
+	for (t1 = l1; t1; t1 = t1->next)
+		l2 = tlpm_add(l2, t1->key, t1->n_bits);
+
+	for (i = 0; i < (1 << 8); ++i) {
+		uint8_t key[] = { rand() % 0xff, rand() % 0xff };
+
+		t1 = tlpm_match(l1, key, 16);
+		t2 = tlpm_match(l2, key, 16);
+
+		assert(!t1 == !t2);
+		if (t1) {
+			assert(t1->n_bits == t2->n_bits);
+			for (j = 0; j < t1->n_bits; ++j)
+				assert((t1->key[j / 8] & (1 << (7 - j % 8))) ==
+				       (t2->key[j / 8] & (1 << (7 - j % 8))));
+		}
+	}
+
+	tlpm_clear(l1);
+	tlpm_clear(l2);
+}
+
+static void test_lpm_map(int keysize)
+{
+	size_t i, j, n_matches, n_matches_after_delete, n_nodes, n_lookups;
+	struct tlpm_node *t, *list = NULL;
+	struct bpf_lpm_trie_key *key;
+	uint8_t *data, *value;
+	int r, map;
+
+	/* Compare behavior of tlpm vs. bpf-lpm. Create a randomized set of
+	 * prefixes and insert it into both tlpm and bpf-lpm. Then run some
+	 * randomized lookups and verify both maps return the same result.
+	 */
+
+	n_matches = 0;
+	n_matches_after_delete = 0;
+	n_nodes = 1 << 8;
+	n_lookups = 1 << 16;
+
+	data = alloca(keysize);
+	memset(data, 0, keysize);
+
+	value = alloca(keysize + 1);
+	memset(value, 0, keysize + 1);
+
+	key = alloca(sizeof(*key) + keysize);
+	memset(key, 0, sizeof(*key) + keysize);
+
+	map = bpf_create_map(BPF_MAP_TYPE_LPM_TRIE,
+			     sizeof(*key) + keysize,
+			     keysize + 1,
+			     4096,
+			     BPF_F_NO_PREALLOC);
+	assert(map >= 0);
+
+	for (i = 0; i < n_nodes; ++i) {
+		for (j = 0; j < keysize; ++j)
+			value[j] = rand() & 0xff;
+		value[keysize] = rand() % (8 * keysize + 1);
+
+		list = tlpm_add(list, value, value[keysize]);
+
+		key->prefixlen = value[keysize];
+		memcpy(key->data, value, keysize);
+		r = bpf_map_update_elem(map, key, value, 0);
+		assert(!r);
+	}
+
+	for (i = 0; i < n_lookups; ++i) {
+		for (j = 0; j < keysize; ++j)
+			data[j] = rand() & 0xff;
+
+		t = tlpm_match(list, data, 8 * keysize);
+
+		key->prefixlen = 8 * keysize;
+		memcpy(key->data, data, keysize);
+		r = bpf_map_lookup_elem(map, key, value);
+		assert(!r || errno == ENOENT);
+		assert(!t == !!r);
+
+		if (t) {
+			++n_matches;
+			assert(t->n_bits == value[keysize]);
+			for (j = 0; j < t->n_bits; ++j)
+				assert((t->key[j / 8] & (1 << (7 - j % 8))) ==
+				       (value[j / 8] & (1 << (7 - j % 8))));
+		}
+	}
+
+	/* Remove the first half of the elements in the tlpm and the
+	 * corresponding nodes from the bpf-lpm.  Then run the same
+	 * large number of random lookups in both and make sure they match.
+	 * Note: we need to count the number of nodes actually inserted
+	 * since there may have been duplicates.
+	 */
+	for (i = 0, t = list; t; i++, t = t->next)
+		;
+	for (j = 0; j < i / 2; ++j) {
+		key->prefixlen = list->n_bits;
+		memcpy(key->data, list->key, keysize);
+		r = bpf_map_delete_elem(map, key);
+		assert(!r);
+		list = tlpm_delete(list, list->key, list->n_bits);
+		assert(list);
+	}
+	for (i = 0; i < n_lookups; ++i) {
+		for (j = 0; j < keysize; ++j)
+			data[j] = rand() & 0xff;
+
+		t = tlpm_match(list, data, 8 * keysize);
+
+		key->prefixlen = 8 * keysize;
+		memcpy(key->data, data, keysize);
+		r = bpf_map_lookup_elem(map, key, value);
+		assert(!r || errno == ENOENT);
+		assert(!t == !!r);
+
+		if (t) {
+			++n_matches_after_delete;
+			assert(t->n_bits == value[keysize]);
+			for (j = 0; j < t->n_bits; ++j)
+				assert((t->key[j / 8] & (1 << (7 - j % 8))) ==
+				       (value[j / 8] & (1 << (7 - j % 8))));
+		}
+	}
+
+	close(map);
+	tlpm_clear(list);
+
+	/* With 255 random nodes in the map, we are pretty likely to match
+	 * something on every lookup. For statistics, use this:
+	 *
+	 *     printf("          nodes: %zu\n"
+	 *            "        lookups: %zu\n"
+	 *            "        matches: %zu\n"
+	 *            "matches(delete): %zu\n",
+	 *            n_nodes, n_lookups, n_matches, n_matches_after_delete);
+	 */
+}
+
+/* Test the implementation with some 'real world' examples */
+
+static void test_lpm_ipaddr(void)
+{
+	struct bpf_lpm_trie_key *key_ipv4;
+	struct bpf_lpm_trie_key *key_ipv6;
+	size_t key_size_ipv4;
+	size_t key_size_ipv6;
+	int map_fd_ipv4;
+	int map_fd_ipv6;
+	__u64 value;
+
+	key_size_ipv4 = sizeof(*key_ipv4) + sizeof(__u32);
+	key_size_ipv6 = sizeof(*key_ipv6) + sizeof(__u32) * 4;
+	key_ipv4 = alloca(key_size_ipv4);
+	key_ipv6 = alloca(key_size_ipv6);
+
+	map_fd_ipv4 = bpf_create_map(BPF_MAP_TYPE_LPM_TRIE,
+				     key_size_ipv4, sizeof(value),
+				     100, BPF_F_NO_PREALLOC);
+	assert(map_fd_ipv4 >= 0);
+
+	map_fd_ipv6 = bpf_create_map(BPF_MAP_TYPE_LPM_TRIE,
+				     key_size_ipv6, sizeof(value),
+				     100, BPF_F_NO_PREALLOC);
+	assert(map_fd_ipv6 >= 0);
+
+	/* Fill data some IPv4 and IPv6 address ranges */
+	value = 1;
+	key_ipv4->prefixlen = 16;
+	inet_pton(AF_INET, "192.168.0.0", key_ipv4->data);
+	assert(bpf_map_update_elem(map_fd_ipv4, key_ipv4, &value, 0) == 0);
+
+	value = 2;
+	key_ipv4->prefixlen = 24;
+	inet_pton(AF_INET, "192.168.0.0", key_ipv4->data);
+	assert(bpf_map_update_elem(map_fd_ipv4, key_ipv4, &value, 0) == 0);
+
+	value = 3;
+	key_ipv4->prefixlen = 24;
+	inet_pton(AF_INET, "192.168.128.0", key_ipv4->data);
+	assert(bpf_map_update_elem(map_fd_ipv4, key_ipv4, &value, 0) == 0);
+
+	value = 5;
+	key_ipv4->prefixlen = 24;
+	inet_pton(AF_INET, "192.168.1.0", key_ipv4->data);
+	assert(bpf_map_update_elem(map_fd_ipv4, key_ipv4, &value, 0) == 0);
+
+	value = 4;
+	key_ipv4->prefixlen = 23;
+	inet_pton(AF_INET, "192.168.0.0", key_ipv4->data);
+	assert(bpf_map_update_elem(map_fd_ipv4, key_ipv4, &value, 0) == 0);
+
+	value = 0xdeadbeef;
+	key_ipv6->prefixlen = 64;
+	inet_pton(AF_INET6, "2a00:1450:4001:814::200e", key_ipv6->data);
+	assert(bpf_map_update_elem(map_fd_ipv6, key_ipv6, &value, 0) == 0);
+
+	/* Set tprefixlen to maximum for lookups */
+	key_ipv4->prefixlen = 32;
+	key_ipv6->prefixlen = 128;
+
+	/* Test some lookups that should come back with a value */
+	inet_pton(AF_INET, "192.168.128.23", key_ipv4->data);
+	assert(bpf_map_lookup_elem(map_fd_ipv4, key_ipv4, &value) == 0);
+	assert(value == 3);
+
+	inet_pton(AF_INET, "192.168.0.1", key_ipv4->data);
+	assert(bpf_map_lookup_elem(map_fd_ipv4, key_ipv4, &value) == 0);
+	assert(value == 2);
+
+	inet_pton(AF_INET6, "2a00:1450:4001:814::", key_ipv6->data);
+	assert(bpf_map_lookup_elem(map_fd_ipv6, key_ipv6, &value) == 0);
+	assert(value == 0xdeadbeef);
+
+	inet_pton(AF_INET6, "2a00:1450:4001:814::1", key_ipv6->data);
+	assert(bpf_map_lookup_elem(map_fd_ipv6, key_ipv6, &value) == 0);
+	assert(value == 0xdeadbeef);
+
+	/* Test some lookups that should not match any entry */
+	inet_pton(AF_INET, "10.0.0.1", key_ipv4->data);
+	assert(bpf_map_lookup_elem(map_fd_ipv4, key_ipv4, &value) == -1 &&
+	       errno == ENOENT);
+
+	inet_pton(AF_INET, "11.11.11.11", key_ipv4->data);
+	assert(bpf_map_lookup_elem(map_fd_ipv4, key_ipv4, &value) == -1 &&
+	       errno == ENOENT);
+
+	inet_pton(AF_INET6, "2a00:ffff::", key_ipv6->data);
+	assert(bpf_map_lookup_elem(map_fd_ipv6, key_ipv6, &value) == -1 &&
+	       errno == ENOENT);
+
+	close(map_fd_ipv4);
+	close(map_fd_ipv6);
+}
+
+static void test_lpm_delete(void)
+{
+	struct bpf_lpm_trie_key *key;
+	size_t key_size;
+	int map_fd;
+	__u64 value;
+
+	key_size = sizeof(*key) + sizeof(__u32);
+	key = alloca(key_size);
+
+	map_fd = bpf_create_map(BPF_MAP_TYPE_LPM_TRIE,
+				key_size, sizeof(value),
+				100, BPF_F_NO_PREALLOC);
+	assert(map_fd >= 0);
+
+	/* Add nodes:
+	 * 192.168.0.0/16   (1)
+	 * 192.168.0.0/24   (2)
+	 * 192.168.128.0/24 (3)
+	 * 192.168.1.0/24   (4)
+	 *
+	 *         (1)
+	 *        /   \
+         *     (IM)    (3)
+	 *    /   \
+         *   (2)  (4)
+	 */
+	value = 1;
+	key->prefixlen = 16;
+	inet_pton(AF_INET, "192.168.0.0", key->data);
+	assert(bpf_map_update_elem(map_fd, key, &value, 0) == 0);
+
+	value = 2;
+	key->prefixlen = 24;
+	inet_pton(AF_INET, "192.168.0.0", key->data);
+	assert(bpf_map_update_elem(map_fd, key, &value, 0) == 0);
+
+	value = 3;
+	key->prefixlen = 24;
+	inet_pton(AF_INET, "192.168.128.0", key->data);
+	assert(bpf_map_update_elem(map_fd, key, &value, 0) == 0);
+
+	value = 4;
+	key->prefixlen = 24;
+	inet_pton(AF_INET, "192.168.1.0", key->data);
+	assert(bpf_map_update_elem(map_fd, key, &value, 0) == 0);
+
+	/* remove non-existent node */
+	key->prefixlen = 32;
+	inet_pton(AF_INET, "10.0.0.1", key->data);
+	assert(bpf_map_lookup_elem(map_fd, key, &value) == -1 &&
+		errno == ENOENT);
+
+	key->prefixlen = 30; // unused prefix so far
+	inet_pton(AF_INET, "192.255.0.0", key->data);
+	assert(bpf_map_delete_elem(map_fd, key) == -1 &&
+		errno == ENOENT);
+
+	key->prefixlen = 16; // same prefix as the root node
+	inet_pton(AF_INET, "192.255.0.0", key->data);
+	assert(bpf_map_delete_elem(map_fd, key) == -1 &&
+		errno == ENOENT);
+
+	/* assert initial lookup */
+	key->prefixlen = 32;
+	inet_pton(AF_INET, "192.168.0.1", key->data);
+	assert(bpf_map_lookup_elem(map_fd, key, &value) == 0);
+	assert(value == 2);
+
+	/* remove leaf node */
+	key->prefixlen = 24;
+	inet_pton(AF_INET, "192.168.0.0", key->data);
+	assert(bpf_map_delete_elem(map_fd, key) == 0);
+
+	key->prefixlen = 32;
+	inet_pton(AF_INET, "192.168.0.1", key->data);
+	assert(bpf_map_lookup_elem(map_fd, key, &value) == 0);
+	assert(value == 1);
+
+	/* remove leaf (and intermediary) node */
+	key->prefixlen = 24;
+	inet_pton(AF_INET, "192.168.1.0", key->data);
+	assert(bpf_map_delete_elem(map_fd, key) == 0);
+
+	key->prefixlen = 32;
+	inet_pton(AF_INET, "192.168.1.1", key->data);
+	assert(bpf_map_lookup_elem(map_fd, key, &value) == 0);
+	assert(value == 1);
+
+	/* remove root node */
+	key->prefixlen = 16;
+	inet_pton(AF_INET, "192.168.0.0", key->data);
+	assert(bpf_map_delete_elem(map_fd, key) == 0);
+
+	key->prefixlen = 32;
+	inet_pton(AF_INET, "192.168.128.1", key->data);
+	assert(bpf_map_lookup_elem(map_fd, key, &value) == 0);
+	assert(value == 3);
+
+	/* remove last node */
+	key->prefixlen = 24;
+	inet_pton(AF_INET, "192.168.128.0", key->data);
+	assert(bpf_map_delete_elem(map_fd, key) == 0);
+
+	key->prefixlen = 32;
+	inet_pton(AF_INET, "192.168.128.1", key->data);
+	assert(bpf_map_lookup_elem(map_fd, key, &value) == -1 &&
+		errno == ENOENT);
+
+	close(map_fd);
+}
+
+static void test_lpm_get_next_key(void)
+{
+	struct bpf_lpm_trie_key *key_p, *next_key_p;
+	size_t key_size;
+	__u32 value = 0;
+	int map_fd;
+
+	key_size = sizeof(*key_p) + sizeof(__u32);
+	key_p = alloca(key_size);
+	next_key_p = alloca(key_size);
+
+	map_fd = bpf_create_map(BPF_MAP_TYPE_LPM_TRIE, key_size, sizeof(value),
+				100, BPF_F_NO_PREALLOC);
+	assert(map_fd >= 0);
+
+	/* empty tree. get_next_key should return ENOENT */
+	assert(bpf_map_get_next_key(map_fd, NULL, key_p) == -1 &&
+	       errno == ENOENT);
+
+	/* get and verify the first key, get the second one should fail. */
+	key_p->prefixlen = 16;
+	inet_pton(AF_INET, "192.168.0.0", key_p->data);
+	assert(bpf_map_update_elem(map_fd, key_p, &value, 0) == 0);
+
+	memset(key_p, 0, key_size);
+	assert(bpf_map_get_next_key(map_fd, NULL, key_p) == 0);
+	assert(key_p->prefixlen == 16 && key_p->data[0] == 192 &&
+	       key_p->data[1] == 168);
+
+	assert(bpf_map_get_next_key(map_fd, key_p, next_key_p) == -1 &&
+	       errno == ENOENT);
+
+	/* no exact matching key should get the first one in post order. */
+	key_p->prefixlen = 8;
+	assert(bpf_map_get_next_key(map_fd, NULL, key_p) == 0);
+	assert(key_p->prefixlen == 16 && key_p->data[0] == 192 &&
+	       key_p->data[1] == 168);
+
+	/* add one more element (total two) */
+	key_p->prefixlen = 24;
+	inet_pton(AF_INET, "192.168.128.0", key_p->data);
+	assert(bpf_map_update_elem(map_fd, key_p, &value, 0) == 0);
+
+	memset(key_p, 0, key_size);
+	assert(bpf_map_get_next_key(map_fd, NULL, key_p) == 0);
+	assert(key_p->prefixlen == 24 && key_p->data[0] == 192 &&
+	       key_p->data[1] == 168 && key_p->data[2] == 128);
+
+	memset(next_key_p, 0, key_size);
+	assert(bpf_map_get_next_key(map_fd, key_p, next_key_p) == 0);
+	assert(next_key_p->prefixlen == 16 && next_key_p->data[0] == 192 &&
+	       next_key_p->data[1] == 168);
+
+	memcpy(key_p, next_key_p, key_size);
+	assert(bpf_map_get_next_key(map_fd, key_p, next_key_p) == -1 &&
+	       errno == ENOENT);
+
+	/* Add one more element (total three) */
+	key_p->prefixlen = 24;
+	inet_pton(AF_INET, "192.168.0.0", key_p->data);
+	assert(bpf_map_update_elem(map_fd, key_p, &value, 0) == 0);
+
+	memset(key_p, 0, key_size);
+	assert(bpf_map_get_next_key(map_fd, NULL, key_p) == 0);
+	assert(key_p->prefixlen == 24 && key_p->data[0] == 192 &&
+	       key_p->data[1] == 168 && key_p->data[2] == 0);
+
+	memset(next_key_p, 0, key_size);
+	assert(bpf_map_get_next_key(map_fd, key_p, next_key_p) == 0);
+	assert(next_key_p->prefixlen == 24 && next_key_p->data[0] == 192 &&
+	       next_key_p->data[1] == 168 && next_key_p->data[2] == 128);
+
+	memcpy(key_p, next_key_p, key_size);
+	assert(bpf_map_get_next_key(map_fd, key_p, next_key_p) == 0);
+	assert(next_key_p->prefixlen == 16 && next_key_p->data[0] == 192 &&
+	       next_key_p->data[1] == 168);
+
+	memcpy(key_p, next_key_p, key_size);
+	assert(bpf_map_get_next_key(map_fd, key_p, next_key_p) == -1 &&
+	       errno == ENOENT);
+
+	/* Add one more element (total four) */
+	key_p->prefixlen = 24;
+	inet_pton(AF_INET, "192.168.1.0", key_p->data);
+	assert(bpf_map_update_elem(map_fd, key_p, &value, 0) == 0);
+
+	memset(key_p, 0, key_size);
+	assert(bpf_map_get_next_key(map_fd, NULL, key_p) == 0);
+	assert(key_p->prefixlen == 24 && key_p->data[0] == 192 &&
+	       key_p->data[1] == 168 && key_p->data[2] == 0);
+
+	memset(next_key_p, 0, key_size);
+	assert(bpf_map_get_next_key(map_fd, key_p, next_key_p) == 0);
+	assert(next_key_p->prefixlen == 24 && next_key_p->data[0] == 192 &&
+	       next_key_p->data[1] == 168 && next_key_p->data[2] == 1);
+
+	memcpy(key_p, next_key_p, key_size);
+	assert(bpf_map_get_next_key(map_fd, key_p, next_key_p) == 0);
+	assert(next_key_p->prefixlen == 24 && next_key_p->data[0] == 192 &&
+	       next_key_p->data[1] == 168 && next_key_p->data[2] == 128);
+
+	memcpy(key_p, next_key_p, key_size);
+	assert(bpf_map_get_next_key(map_fd, key_p, next_key_p) == 0);
+	assert(next_key_p->prefixlen == 16 && next_key_p->data[0] == 192 &&
+	       next_key_p->data[1] == 168);
+
+	memcpy(key_p, next_key_p, key_size);
+	assert(bpf_map_get_next_key(map_fd, key_p, next_key_p) == -1 &&
+	       errno == ENOENT);
+
+	/* Add one more element (total five) */
+	key_p->prefixlen = 28;
+	inet_pton(AF_INET, "192.168.1.128", key_p->data);
+	assert(bpf_map_update_elem(map_fd, key_p, &value, 0) == 0);
+
+	memset(key_p, 0, key_size);
+	assert(bpf_map_get_next_key(map_fd, NULL, key_p) == 0);
+	assert(key_p->prefixlen == 24 && key_p->data[0] == 192 &&
+	       key_p->data[1] == 168 && key_p->data[2] == 0);
+
+	memset(next_key_p, 0, key_size);
+	assert(bpf_map_get_next_key(map_fd, key_p, next_key_p) == 0);
+	assert(next_key_p->prefixlen == 28 && next_key_p->data[0] == 192 &&
+	       next_key_p->data[1] == 168 && next_key_p->data[2] == 1 &&
+	       next_key_p->data[3] == 128);
+
+	memcpy(key_p, next_key_p, key_size);
+	assert(bpf_map_get_next_key(map_fd, key_p, next_key_p) == 0);
+	assert(next_key_p->prefixlen == 24 && next_key_p->data[0] == 192 &&
+	       next_key_p->data[1] == 168 && next_key_p->data[2] == 1);
+
+	memcpy(key_p, next_key_p, key_size);
+	assert(bpf_map_get_next_key(map_fd, key_p, next_key_p) == 0);
+	assert(next_key_p->prefixlen == 24 && next_key_p->data[0] == 192 &&
+	       next_key_p->data[1] == 168 && next_key_p->data[2] == 128);
+
+	memcpy(key_p, next_key_p, key_size);
+	assert(bpf_map_get_next_key(map_fd, key_p, next_key_p) == 0);
+	assert(next_key_p->prefixlen == 16 && next_key_p->data[0] == 192 &&
+	       next_key_p->data[1] == 168);
+
+	memcpy(key_p, next_key_p, key_size);
+	assert(bpf_map_get_next_key(map_fd, key_p, next_key_p) == -1 &&
+	       errno == ENOENT);
+
+	/* no exact matching key should return the first one in post order */
+	key_p->prefixlen = 22;
+	inet_pton(AF_INET, "192.168.1.0", key_p->data);
+	assert(bpf_map_get_next_key(map_fd, key_p, next_key_p) == 0);
+	assert(next_key_p->prefixlen == 24 && next_key_p->data[0] == 192 &&
+	       next_key_p->data[1] == 168 && next_key_p->data[2] == 0);
+
+	close(map_fd);
+}
+
+#define MAX_TEST_KEYS	4
+struct lpm_mt_test_info {
+	int cmd; /* 0: update, 1: delete, 2: lookup, 3: get_next_key */
+	int iter;
+	int map_fd;
+	struct {
+		__u32 prefixlen;
+		__u32 data;
+	} key[MAX_TEST_KEYS];
+};
+
+static void *lpm_test_command(void *arg)
+{
+	int i, j, ret, iter, key_size;
+	struct lpm_mt_test_info *info = arg;
+	struct bpf_lpm_trie_key *key_p;
+
+	key_size = sizeof(struct bpf_lpm_trie_key) + sizeof(__u32);
+	key_p = alloca(key_size);
+	for (iter = 0; iter < info->iter; iter++)
+		for (i = 0; i < MAX_TEST_KEYS; i++) {
+			/* first half of iterations in forward order,
+			 * and second half in backward order.
+			 */
+			j = (iter < (info->iter / 2)) ? i : MAX_TEST_KEYS - i - 1;
+			key_p->prefixlen = info->key[j].prefixlen;
+			memcpy(key_p->data, &info->key[j].data, sizeof(__u32));
+			if (info->cmd == 0) {
+				__u32 value = j;
+				/* update must succeed */
+				assert(bpf_map_update_elem(info->map_fd, key_p, &value, 0) == 0);
+			} else if (info->cmd == 1) {
+				ret = bpf_map_delete_elem(info->map_fd, key_p);
+				assert(ret == 0 || errno == ENOENT);
+			} else if (info->cmd == 2) {
+				__u32 value;
+				ret = bpf_map_lookup_elem(info->map_fd, key_p, &value);
+				assert(ret == 0 || errno == ENOENT);
+			} else {
+				struct bpf_lpm_trie_key *next_key_p = alloca(key_size);
+				ret = bpf_map_get_next_key(info->map_fd, key_p, next_key_p);
+				assert(ret == 0 || errno == ENOENT || errno == ENOMEM);
+			}
+		}
+
+	// Pass successful exit info back to the main thread
+	pthread_exit((void *)info);
+}
+
+static void setup_lpm_mt_test_info(struct lpm_mt_test_info *info, int map_fd)
+{
+	info->iter = 2000;
+	info->map_fd = map_fd;
+	info->key[0].prefixlen = 16;
+	inet_pton(AF_INET, "192.168.0.0", &info->key[0].data);
+	info->key[1].prefixlen = 24;
+	inet_pton(AF_INET, "192.168.0.0", &info->key[1].data);
+	info->key[2].prefixlen = 24;
+	inet_pton(AF_INET, "192.168.128.0", &info->key[2].data);
+	info->key[3].prefixlen = 24;
+	inet_pton(AF_INET, "192.168.1.0", &info->key[3].data);
+}
+
+static void test_lpm_multi_thread(void)
+{
+	struct lpm_mt_test_info info[4];
+	size_t key_size, value_size;
+	pthread_t thread_id[4];
+	int i, map_fd;
+	void *ret;
+
+	/* create a trie */
+	value_size = sizeof(__u32);
+	key_size = sizeof(struct bpf_lpm_trie_key) + value_size;
+	map_fd = bpf_create_map(BPF_MAP_TYPE_LPM_TRIE, key_size, value_size,
+				100, BPF_F_NO_PREALLOC);
+
+	/* create 4 threads to test update, delete, lookup and get_next_key */
+	setup_lpm_mt_test_info(&info[0], map_fd);
+	for (i = 0; i < 4; i++) {
+		if (i != 0)
+			memcpy(&info[i], &info[0], sizeof(info[i]));
+		info[i].cmd = i;
+		assert(pthread_create(&thread_id[i], NULL, &lpm_test_command, &info[i]) == 0);
+	}
+
+	for (i = 0; i < 4; i++)
+		assert(pthread_join(thread_id[i], &ret) == 0 && ret == (void *)&info[i]);
+
+	close(map_fd);
+}
+
+int main(void)
+{
+	int i;
+
+	/* we want predictable, pseudo random tests */
+	srand(0xf00ba1);
+
+	test_lpm_basic();
+	test_lpm_order();
+
+	/* Test with 8, 16, 24, 32, ... 128 bit prefix length */
+	for (i = 1; i <= 16; ++i)
+		test_lpm_map(i);
+
+	test_lpm_ipaddr();
+	test_lpm_delete();
+	test_lpm_get_next_key();
+	test_lpm_multi_thread();
+
+	printf("test_lpm: OK\n");
+	return 0;
+}