allowedips: rename from routingtable

Makes it more clear that this _not_ a routing table replacement.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

1 files changed, 510 insertions, 0 deletions

diff --git a/src/selftest/allowedips.h b/src/selftest/allowedips.h
new file mode 100644
index 0000000..78b019d
--- /dev/null
+++ b/src/selftest/allowedips.h
@@ -0,0 +1,510 @@
+/* Copyright (C) 2015-2017 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. */
+
+#ifdef DEBUG
+
+#ifdef DEBUG_PRINT_TRIE_GRAPHVIZ
+#include <linux/siphash.h>
+static __init void print_node(struct allowedips_node *node, u8 bits)
+{
+	u32 color = 0;
+	char *style = "dotted";
+	char *fmt_connection = KERN_DEBUG "\t\"%p/%d\" -> \"%p/%d\";\n";
+	char *fmt_declaration = KERN_DEBUG "\t\"%p/%d\"[style=%s, color=\"#%06x\"];\n";
+	if (bits == 32) {
+		fmt_connection = KERN_DEBUG "\t\"%pI4/%d\" -> \"%pI4/%d\";\n";
+		fmt_declaration = KERN_DEBUG "\t\"%pI4/%d\"[style=%s, color=\"#%06x\"];\n";
+	} else if (bits == 128) {
+		fmt_connection = KERN_DEBUG "\t\"%pI6/%d\" -> \"%pI6/%d\";\n";
+		fmt_declaration = KERN_DEBUG "\t\"%pI6/%d\"[style=%s, color=\"#%06x\"];\n";
+	}
+	if (node->peer) {
+		hsiphash_key_t key = { 0 };
+		memcpy(&key, &node->peer, sizeof(node->peer));
+		color = hsiphash_1u32(0xdeadbeef, &key) % 200 << 16 | hsiphash_1u32(0xbabecafe, &key) % 200 << 8 | hsiphash_1u32(0xabad1dea, &key) % 200;
+		style = "bold";
+	}
+	printk(fmt_declaration, node->bits, node->cidr, style, color);
+	if (node->bit[0]) {
+		printk(fmt_connection, node->bits, node->cidr, node->bit[0]->bits, node->bit[0]->cidr);
+		print_node(node->bit[0], bits);
+	}
+	if (node->bit[1]) {
+		printk(fmt_connection, node->bits, node->cidr, node->bit[1]->bits, node->bit[1]->cidr);
+		print_node(node->bit[1], bits);
+	}
+}
+static __init void print_tree(struct allowedips_node *top, u8 bits)
+{
+	printk(KERN_DEBUG "digraph trie {\n");
+	print_node(top, bits);
+	printk(KERN_DEBUG "}\n");
+}
+#endif
+
+#ifdef DEBUG_RANDOM_TRIE
+#define NUM_PEERS 2000
+#define NUM_RAND_ROUTES 400
+#define NUM_MUTATED_ROUTES 100
+#define NUM_QUERIES (NUM_RAND_ROUTES * NUM_MUTATED_ROUTES * 30)
+#include <linux/random.h>
+struct horrible_allowedips {
+	struct hlist_head head;
+};
+struct horrible_allowedips_node {
+	struct hlist_node table;
+	union nf_inet_addr ip;
+	union nf_inet_addr mask;
+	uint8_t ip_version;
+	void *value;
+};
+static __init void horrible_allowedips_init(struct horrible_allowedips *table)
+{
+	INIT_HLIST_HEAD(&table->head);
+}
+static __init void horrible_allowedips_free(struct horrible_allowedips *table)
+{
+	struct hlist_node *h;
+	struct horrible_allowedips_node *node;
+	hlist_for_each_entry_safe(node, h, &table->head, table) {
+		hlist_del(&node->table);
+		kfree(node);
+	}
+}
+static __init inline union nf_inet_addr horrible_cidr_to_mask(uint8_t cidr)
+{
+	union nf_inet_addr mask;
+	memset(&mask, 0x00, 128 / 8);
+	memset(&mask, 0xff, cidr / 8);
+	if (cidr % 32)
+		mask.all[cidr / 32] = htonl((0xFFFFFFFFUL << (32 - (cidr % 32))) & 0xFFFFFFFFUL);
+	return mask;
+}
+static __init inline uint8_t horrible_mask_to_cidr(union nf_inet_addr subnet)
+{
+	return hweight32(subnet.all[0])
+	     + hweight32(subnet.all[1])
+	     + hweight32(subnet.all[2])
+	     + hweight32(subnet.all[3]);
+}
+static __init inline void horrible_mask_self(struct horrible_allowedips_node *node)
+{
+	if (node->ip_version == 4)
+		node->ip.ip &= node->mask.ip;
+	else if (node->ip_version == 6) {
+		node->ip.ip6[0] &= node->mask.ip6[0];
+		node->ip.ip6[1] &= node->mask.ip6[1];
+		node->ip.ip6[2] &= node->mask.ip6[2];
+		node->ip.ip6[3] &= node->mask.ip6[3];
+	}
+}
+static __init inline bool horrible_match_v4(const struct horrible_allowedips_node *node, struct in_addr *ip)
+{
+	return (ip->s_addr & node->mask.ip) == node->ip.ip;
+}
+static __init inline bool horrible_match_v6(const struct horrible_allowedips_node *node, struct in6_addr *ip)
+{
+	return	(ip->in6_u.u6_addr32[0] & node->mask.ip6[0]) == node->ip.ip6[0] &&
+		(ip->in6_u.u6_addr32[1] & node->mask.ip6[1]) == node->ip.ip6[1] &&
+		(ip->in6_u.u6_addr32[2] & node->mask.ip6[2]) == node->ip.ip6[2] &&
+		(ip->in6_u.u6_addr32[3] & node->mask.ip6[3]) == node->ip.ip6[3];
+}
+static __init void horrible_insert_ordered(struct horrible_allowedips *table, struct horrible_allowedips_node *node)
+{
+	struct horrible_allowedips_node *other = NULL, *where = NULL;
+	uint8_t my_cidr = horrible_mask_to_cidr(node->mask);
+	hlist_for_each_entry(other, &table->head, table) {
+		if (!memcmp(&other->mask, &node->mask, sizeof(union nf_inet_addr)) &&
+		    !memcmp(&other->ip, &node->ip, sizeof(union nf_inet_addr)) &&
+		    other->ip_version == node->ip_version) {
+			other->value = node->value;
+			kfree(node);
+			return;
+		}
+		where = other;
+		if (horrible_mask_to_cidr(other->mask) <= my_cidr)
+			break;
+	}
+	if (!other && !where)
+		hlist_add_head(&node->table, &table->head);
+	else if (!other)
+		hlist_add_behind(&node->table, &where->table);
+	else
+		hlist_add_before(&node->table, &where->table);
+}
+static __init int horrible_allowedips_insert_v4(struct horrible_allowedips *table, struct in_addr *ip, uint8_t cidr, void *value)
+{
+	struct horrible_allowedips_node *node = kzalloc(sizeof(struct horrible_allowedips_node), GFP_KERNEL);
+	if (!node)
+		return -ENOMEM;
+	node->ip.in = *ip;
+	node->mask = horrible_cidr_to_mask(cidr);
+	node->ip_version = 4;
+	node->value = value;
+	horrible_mask_self(node);
+	horrible_insert_ordered(table, node);
+	return 0;
+}
+static __init int horrible_allowedips_insert_v6(struct horrible_allowedips *table, struct in6_addr *ip, uint8_t cidr, void *value)
+{
+	struct horrible_allowedips_node *node = kzalloc(sizeof(struct horrible_allowedips_node), GFP_KERNEL);
+	if (!node)
+		return -ENOMEM;
+	node->ip.in6 = *ip;
+	node->mask = horrible_cidr_to_mask(cidr);
+	node->ip_version = 6;
+	node->value = value;
+	horrible_mask_self(node);
+	horrible_insert_ordered(table, node);
+	return 0;
+}
+static __init void *horrible_allowedips_lookup_v4(struct horrible_allowedips *table, struct in_addr *ip)
+{
+	struct horrible_allowedips_node *node;
+	void *ret = NULL;
+	hlist_for_each_entry(node, &table->head, table) {
+		if (node->ip_version != 4)
+			continue;
+		if (horrible_match_v4(node, ip)) {
+			ret = node->value;
+			break;
+		}
+	}
+	return ret;
+}
+static __init void *horrible_allowedips_lookup_v6(struct horrible_allowedips *table, struct in6_addr *ip)
+{
+	struct horrible_allowedips_node *node;
+	void *ret = NULL;
+	hlist_for_each_entry(node, &table->head, table) {
+		if (node->ip_version != 6)
+			continue;
+		if (horrible_match_v6(node, ip)) {
+			ret = node->value;
+			break;
+		}
+	}
+	return ret;
+}
+
+static __init bool randomized_test(void)
+{
+	bool ret = false;
+	unsigned int i, j, k, mutate_amount, cidr;
+	struct wireguard_peer **peers, *peer;
+	struct allowedips t;
+	struct horrible_allowedips h;
+	u8 ip[16], mutate_mask[16], mutated[16];
+
+	allowedips_init(&t);
+	horrible_allowedips_init(&h);
+
+	peers = kcalloc(NUM_PEERS, sizeof(struct wireguard_peer *), GFP_KERNEL);
+	if (!peers) {
+		pr_info("allowedips random self-test: out of memory\n");
+		goto free;
+	}
+	for (i = 0; i < NUM_PEERS; ++i) {
+		peers[i] = kzalloc(sizeof(struct wireguard_peer), GFP_KERNEL);
+		if (!peers[i]) {
+			pr_info("allowedips random self-test: out of memory\n");
+			goto free;
+		}
+		kref_init(&peers[i]->refcount);
+	}
+
+	for (i = 0; i < NUM_RAND_ROUTES; ++i) {
+		prandom_bytes(ip, 4);
+		cidr = prandom_u32_max(32) + 1;
+		peer = peers[prandom_u32_max(NUM_PEERS)];
+		if (allowedips_insert_v4(&t, (struct in_addr *)ip, cidr, peer) < 0) {
+			pr_info("allowedips random self-test: out of memory\n");
+			goto free;
+		}
+		if (horrible_allowedips_insert_v4(&h, (struct in_addr *)ip, cidr, peer) < 0) {
+			pr_info("allowedips random self-test: out of memory\n");
+			goto free;
+		}
+		for (j = 0; j < NUM_MUTATED_ROUTES; ++j) {
+			memcpy(mutated, ip, 4);
+			prandom_bytes(mutate_mask, 4);
+			mutate_amount = prandom_u32_max(32);
+			for (k = 0; k < mutate_amount / 8; ++k)
+				mutate_mask[k] = 0xff;
+			mutate_mask[k] = 0xff << ((8 - (mutate_amount % 8)) % 8);
+			for (; k < 4; ++k)
+				mutate_mask[k] = 0;
+			for (k = 0; k < 4; ++k)
+				mutated[k] = (mutated[k] & mutate_mask[k]) | (~mutate_mask[k] & prandom_u32_max(256));
+			cidr = prandom_u32_max(32) + 1;
+			peer = peers[prandom_u32_max(NUM_PEERS)];
+			if (allowedips_insert_v4(&t, (struct in_addr *)mutated, cidr, peer) < 0) {
+				pr_info("allowedips random self-test: out of memory\n");
+				goto free;
+			}
+			if (horrible_allowedips_insert_v4(&h, (struct in_addr *)mutated, cidr, peer)) {
+				pr_info("allowedips random self-test: out of memory\n");
+				goto free;
+			}
+		}
+	}
+
+	for (i = 0; i < NUM_RAND_ROUTES; ++i) {
+		prandom_bytes(ip, 16);
+		cidr = prandom_u32_max(128) + 1;
+		peer = peers[prandom_u32_max(NUM_PEERS)];
+		if (allowedips_insert_v6(&t, (struct in6_addr *)ip, cidr, peer) < 0) {
+			pr_info("allowedips random self-test: out of memory\n");
+			goto free;
+		}
+		if (horrible_allowedips_insert_v6(&h, (struct in6_addr *)ip, cidr, peer) < 0) {
+			pr_info("allowedips random self-test: out of memory\n");
+			goto free;
+		}
+		for (j = 0; j < NUM_MUTATED_ROUTES; ++j) {
+			memcpy(mutated, ip, 16);
+			prandom_bytes(mutate_mask, 16);
+			mutate_amount = prandom_u32_max(128);
+			for (k = 0; k < mutate_amount / 8; ++k)
+				mutate_mask[k] = 0xff;
+			mutate_mask[k] = 0xff << ((8 - (mutate_amount % 8)) % 8);
+			for (; k < 4; ++k)
+				mutate_mask[k] = 0;
+			for (k = 0; k < 4; ++k)
+				mutated[k] = (mutated[k] & mutate_mask[k]) | (~mutate_mask[k] & prandom_u32_max(256));
+			cidr = prandom_u32_max(128) + 1;
+			peer = peers[prandom_u32_max(NUM_PEERS)];
+			if (allowedips_insert_v6(&t, (struct in6_addr *)mutated, cidr, peer) < 0) {
+				pr_info("allowedips random self-test: out of memory\n");
+				goto free;
+			}
+			if (horrible_allowedips_insert_v6(&h, (struct in6_addr *)mutated, cidr, peer)) {
+				pr_info("allowedips random self-test: out of memory\n");
+				goto free;
+			}
+		}
+	}
+
+#ifdef DEBUG_PRINT_TRIE_GRAPHVIZ
+	print_tree(t.root4, 32);
+	print_tree(t.root6, 128);
+#endif
+
+	for (i = 0; i < NUM_QUERIES; ++i) {
+		prandom_bytes(ip, 4);
+		if (lookup(t.root4, 32, ip) != horrible_allowedips_lookup_v4(&h, (struct in_addr *)ip)) {
+			pr_info("allowedips random self-test: FAIL\n");
+			goto free;
+		}
+	}
+
+	for (i = 0; i < NUM_QUERIES; ++i) {
+		prandom_bytes(ip, 16);
+		if (lookup(t.root6, 128, ip) != horrible_allowedips_lookup_v6(&h, (struct in6_addr *)ip)) {
+			pr_info("allowedips random self-test: FAIL\n");
+			goto free;
+		}
+	}
+	ret = true;
+
+free:
+	allowedips_free(&t);
+	horrible_allowedips_free(&h);
+	if (peers) {
+		for (i = 0; i < NUM_PEERS; ++i)
+			kfree(peers[i]);
+	}
+	kfree(peers);
+	return ret;
+}
+#endif
+
+static __init inline struct in_addr *ip4(u8 a, u8 b, u8 c, u8 d)
+{
+	static struct in_addr ip;
+	u8 *split = (u8 *)&ip;
+	split[0] = a;
+	split[1] = b;
+	split[2] = c;
+	split[3] = d;
+	return &ip;
+}
+static __init inline struct in6_addr *ip6(u32 a, u32 b, u32 c, u32 d)
+{
+	static struct in6_addr ip;
+	__be32 *split = (__be32 *)&ip;
+	split[0] = cpu_to_be32(a);
+	split[1] = cpu_to_be32(b);
+	split[2] = cpu_to_be32(c);
+	split[3] = cpu_to_be32(d);
+	return &ip;
+}
+
+#define init_peer(name) do { \
+	name = kzalloc(sizeof(struct wireguard_peer), GFP_KERNEL); \
+	if (!name) { \
+		pr_info("allowedips self-test: out of memory\n"); \
+		goto free; \
+	} \
+	kref_init(&name->refcount); \
+} while (0)
+
+#define insert(version, mem, ipa, ipb, ipc, ipd, cidr) \
+	allowedips_insert_v##version(&t, ip##version(ipa, ipb, ipc, ipd), cidr, mem, &mutex)
+
+#define maybe_fail \
+	++i; \
+	if (!_s) { \
+		pr_info("allowedips self-test %zu: FAIL\n", i); \
+		success = false; \
+	}
+
+#define test(version, mem, ipa, ipb, ipc, ipd) do { \
+	bool _s = lookup(t.root##version, version == 4 ? 32 : 128, ip##version(ipa, ipb, ipc, ipd)) == mem; \
+	maybe_fail \
+} while (0)
+
+#define test_negative(version, mem, ipa, ipb, ipc, ipd) do { \
+	bool _s = lookup(t.root##version, version == 4 ? 32 : 128, ip##version(ipa, ipb, ipc, ipd)) != mem; \
+	maybe_fail \
+} while (0)
+
+bool __init allowedips_selftest(void)
+{
+	DEFINE_MUTEX(mutex);
+	struct allowedips t;
+	struct wireguard_peer *a = NULL, *b = NULL, *c = NULL, *d = NULL, *e = NULL, *f = NULL, *g = NULL, *h = NULL;
+	size_t i = 0;
+	bool success = false;
+	struct in6_addr ip;
+	__be64 part;
+
+	mutex_init(&mutex);
+
+	mutex_lock(&mutex);
+
+	allowedips_init(&t);
+	init_peer(a);
+	init_peer(b);
+	init_peer(c);
+	init_peer(d);
+	init_peer(e);
+	init_peer(f);
+	init_peer(g);
+	init_peer(h);
+
+	insert(4, a, 192, 168, 4, 0, 24);
+	insert(4, b, 192, 168, 4, 4, 32);
+	insert(4, c, 192, 168, 0, 0, 16);
+	insert(4, d, 192, 95, 5, 64, 27);
+	insert(4, c, 192, 95, 5, 65, 27); /* replaces previous entry, and maskself is required */
+	insert(6, d, 0x26075300, 0x60006b00, 0, 0xc05f0543, 128);
+	insert(6, c, 0x26075300, 0x60006b00, 0, 0, 64);
+	insert(4, e, 0, 0, 0, 0, 0);
+	insert(6, e, 0, 0, 0, 0, 0);
+	insert(6, f, 0, 0, 0, 0, 0); /* replaces previous entry */
+	insert(6, g, 0x24046800, 0, 0, 0, 32);
+	insert(6, h, 0x24046800, 0x40040800, 0xdeadbeef, 0xdeadbeef, 64); /* maskself is required */
+	insert(6, a, 0x24046800, 0x40040800, 0xdeadbeef, 0xdeadbeef, 128);
+	insert(6, c, 0x24446800, 0x40e40800, 0xdeaebeef, 0xdefbeef, 128);
+	insert(6, b, 0x24446800, 0xf0e40800, 0xeeaebeef, 0, 98);
+	insert(4, g, 64, 15, 112, 0, 20);
+	insert(4, h, 64, 15, 123, 211, 25); /* maskself is required */
+	insert(4, a, 10, 0, 0, 0, 25);
+	insert(4, b, 10, 0, 0, 128, 25);
+	insert(4, a, 10, 1, 0, 0, 30);
+	insert(4, b, 10, 1, 0, 4, 30);
+	insert(4, c, 10, 1, 0, 8, 29);
+	insert(4, d, 10, 1, 0, 16, 29);
+
+#ifdef DEBUG_PRINT_TRIE_GRAPHVIZ
+	print_tree(t.root4, 32);
+	print_tree(t.root6, 128);
+#endif
+
+	success = true;
+
+	test(4, a, 192, 168, 4, 20);
+	test(4, a, 192, 168, 4, 0);
+	test(4, b, 192, 168, 4, 4);
+	test(4, c, 192, 168, 200, 182);
+	test(4, c, 192, 95, 5, 68);
+	test(4, e, 192, 95, 5, 96);
+	test(6, d, 0x26075300, 0x60006b00, 0, 0xc05f0543);
+	test(6, c, 0x26075300, 0x60006b00, 0, 0xc02e01ee);
+	test(6, f, 0x26075300, 0x60006b01, 0, 0);
+	test(6, g, 0x24046800, 0x40040806, 0, 0x1006);
+	test(6, g, 0x24046800, 0x40040806, 0x1234, 0x5678);
+	test(6, f, 0x240467ff, 0x40040806, 0x1234, 0x5678);
+	test(6, f, 0x24046801, 0x40040806, 0x1234, 0x5678);
+	test(6, h, 0x24046800, 0x40040800, 0x1234, 0x5678);
+	test(6, h, 0x24046800, 0x40040800, 0, 0);
+	test(6, h, 0x24046800, 0x40040800, 0x10101010, 0x10101010);
+	test(6, a, 0x24046800, 0x40040800, 0xdeadbeef, 0xdeadbeef);
+	test(4, g, 64, 15, 116, 26);
+	test(4, g, 64, 15, 127, 3);
+	test(4, g, 64, 15, 123, 1);
+	test(4, h, 64, 15, 123, 128);
+	test(4, h, 64, 15, 123, 129);
+	test(4, a, 10, 0, 0, 52);
+	test(4, b, 10, 0, 0, 220);
+	test(4, a, 10, 1, 0, 2);
+	test(4, b, 10, 1, 0, 6);
+	test(4, c, 10, 1, 0, 10);
+	test(4, d, 10, 1, 0, 20);
+
+	insert(4, a, 1, 0, 0, 0, 32);
+	insert(4, a, 64, 0, 0, 0, 32);
+	insert(4, a, 128, 0, 0, 0, 32);
+	insert(4, a, 192, 0, 0, 0, 32);
+	insert(4, a, 255, 0, 0, 0, 32);
+	allowedips_remove_by_peer(&t, a, &mutex);
+	test_negative(4, a, 1, 0, 0, 0);
+	test_negative(4, a, 64, 0, 0, 0);
+	test_negative(4, a, 128, 0, 0, 0);
+	test_negative(4, a, 192, 0, 0, 0);
+	test_negative(4, a, 255, 0, 0, 0);
+
+	allowedips_free(&t, &mutex);
+	allowedips_init(&t);
+	insert(4, a, 192, 168, 0, 0, 16);
+	insert(4, a, 192, 168, 0, 0, 24);
+	allowedips_remove_by_peer(&t, a, &mutex);
+	test_negative(4, a, 192, 168, 0, 1);
+
+	/* These will hit the BUG_ON(len >= 128) in free_node if something goes wrong. */
+	for (i = 0; i < 128; ++i) {
+		part = cpu_to_be64(~(1LLU << (i % 64)));
+		memset(&ip, 0xff, 16);
+		memcpy((u8 *)&ip + (i < 64) * 8, &part, 8);
+		allowedips_insert_v6(&t, &ip, 128, a, &mutex);
+	}
+
+#ifdef DEBUG_RANDOM_TRIE
+	if (success)
+		success = randomized_test();
+#endif
+
+	if (success)
+		pr_info("allowedips self-tests: pass\n");
+
+free:
+	allowedips_free(&t, &mutex);
+	kfree(a);
+	kfree(b);
+	kfree(c);
+	kfree(d);
+	kfree(e);
+	kfree(f);
+	kfree(g);
+	kfree(h);
+	mutex_unlock(&mutex);
+
+	return success;
+}
+#undef test_negative
+#undef test
+#undef remove
+#undef insert
+#undef init_peer
+
+#endif