From: David Herrmann <dh.herrm...@gmail.com>
The first part of this program runs randomized tests against the
lpm-bpf-map. It implements a "Trivial Longest Prefix Match" (tlpm)
based on simple, linear, single 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.
The second part uses 'real world' IPv4 and IPv6 addresses and tests
the trie with those.
Signed-off-by: David Herrmann <dh.herrm...@gmail.com>
Signed-off-by: Daniel Mack <dan...@zonque.org>
---
tools/testing/selftests/bpf/.gitignore | 1 +
tools/testing/selftests/bpf/Makefile | 4 +-
tools/testing/selftests/bpf/test_lpm_map.c | 358 +++++++++++++++++++++++++++++
3 files changed, 361 insertions(+), 2 deletions(-)
create mode 100644 tools/testing/selftests/bpf/test_lpm_map.c
diff --git a/tools/testing/selftests/bpf/.gitignore
b/tools/testing/selftests/bpf/.gitignore
index 071431b..d3b1c9b 100644
--- a/tools/testing/selftests/bpf/.gitignore
+++ b/tools/testing/selftests/bpf/.gitignore
@@ -1,3 +1,4 @@
test_verifier
test_maps
test_lru_map
+test_lpm_map
diff --git a/tools/testing/selftests/bpf/Makefile
b/tools/testing/selftests/bpf/Makefile
index 7a5f245..064a3e5 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -1,8 +1,8 @@
CFLAGS += -Wall -O2 -I../../../../usr/include
-test_objs = test_verifier test_maps test_lru_map
+test_objs = test_verifier test_maps test_lru_map test_lpm_map
-TEST_PROGS := test_verifier test_maps test_lru_map test_kmod.sh
+TEST_PROGS := test_verifier test_maps test_lru_map test_lpm_map test_kmod.sh
TEST_FILES := $(test_objs)
all: $(test_objs)
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 0000000..dd83f0b
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_lpm_map.c
@@ -0,0 +1,358 @@
+/*
+ * 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 <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <arpa/inet.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+
+#include "bpf_sys.h"
+#include "bpf_util.h"
+
+struct tlpm_node {
+ struct tlpm_node *next;
+ size_t n_bits;
+ uint8_t key[];
+};
+
+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;
+
+ /* add new entry with @key/@n_bits to @list and return new head */
+
+ n = (n_bits + 7) / 8;
+ 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 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));
+
+ 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(void)
+{
+ size_t i, j, n_matches, n_nodes, n_lookups;
+ struct tlpm_node *t, *list = NULL;
+ struct bpf_lpm_trie_key *key;
+ uint8_t value[8] = {};
+ 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_nodes = 1 << 8;
+ n_lookups = 1 << 16;
+
+ key = alloca(sizeof(*key) + 4);
+ memset(key, 0, sizeof(*key) + 4);
+
+ map = bpf_map_create(BPF_MAP_TYPE_LPM_TRIE,
+ sizeof(*key) + 4,
+ sizeof(value),
+ 4096,
+ BPF_F_NO_PREALLOC);
+ assert(map >= 0);
+
+ for (i = 0; i < n_nodes; ++i) {
+ value[0] = rand() & 0xff;
+ value[1] = rand() & 0xff;
+ value[2] = rand() & 0xff;
+ value[3] = rand() & 0xff;
+ value[4] = rand() % 33;
+
+ list = tlpm_add(list, value, value[4]);
+
+ key->prefixlen = value[4];
+ memcpy(key->data, value, 4);
+ r = bpf_map_update(map, key, value, 0);
+ assert(!r);
+ }
+
+ for (i = 0; i < n_lookups; ++i) {
+ uint8_t data[] = {
+ rand() % 0xff,
+ rand() % 0xff,
+ rand() % 0xff,
+ rand() % 0xff
+ };
+
+ t = tlpm_match(list, data, 32);
+
+ key->prefixlen = 32;
+ memcpy(key->data, data, 4);
+ r = bpf_map_lookup(map, key, value);
+ assert(!r || errno == ENOENT);
+ assert(!t == !!r);
+
+ if (t) {
+ ++n_matches;
+ assert(t->n_bits == value[4]);
+ 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", n_nodes, n_lookups, n_matches);
+ */
+}
+
+/* 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_map_create(BPF_MAP_TYPE_LPM_TRIE,
+ key_size_ipv4, sizeof(value),
+ 100, BPF_F_NO_PREALLOC);
+ assert(map_fd_ipv4 >= 0);
+
+ map_fd_ipv6 = bpf_map_create(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(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(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(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(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(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(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(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(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(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(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(map_fd_ipv4, key_ipv4, &value) == -1 &&
+ errno == ENOENT);
+
+ inet_pton(AF_INET, "11.11.11.11", key_ipv4->data);
+ assert(bpf_map_lookup(map_fd_ipv4, key_ipv4, &value) == -1 &&
+ errno == ENOENT);
+
+ inet_pton(AF_INET6, "2a00:ffff::", key_ipv6->data);
+ assert(bpf_map_lookup(map_fd_ipv6, key_ipv6, &value) == -1 &&
+ errno == ENOENT);
+
+ close(map_fd_ipv4);
+ close(map_fd_ipv6);
+}
+
+int main(void)
+{
+ struct rlimit limit = { RLIM_INFINITY, RLIM_INFINITY };
+ int ret;
+
+ /* we want predictable, pseudo random tests */
+ srand(0xf00ba1);
+
+ /* allow unlimited locked memory */
+ ret = setrlimit(RLIMIT_MEMLOCK, &limit);
+ if (ret < 0)
+ perror("Unable to lift memlock rlimit");
+
+ test_lpm_basic();
+ test_lpm_order();
+ test_lpm_map();
+ test_lpm_ipaddr();
+
+ printf("test_lpm: OK\n");
+ return 0;
+}
--
2.9.3
