allowedips: maintain per-peer list of allowedips

This makes `wg show` and `wg showconf` and the like significantly
faster, since we don't have to iterate through every node of the trie
for every single peer. It also makes netlink cursor resumption much less
problematic, since we're just iterating through a list, rather than
having to save a traversal stack.

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

1 files changed, 43 insertions, 50 deletions

diff --git a/src/selftest/allowedips.c b/src/selftest/allowedips.c
index 379ac31..6e244a9 100644
--- a/src/selftest/allowedips.c
+++ b/src/selftest/allowedips.c
@@ -452,47 +452,14 @@ static __init inline struct in6_addr *ip6(u32 a, u32 b, u32 c, u32 d)
 	return &ip;
 }
 
-struct walk_ctx {
-	int count;
-	bool found_a, found_b, found_c, found_d, found_e;
-	bool found_other;
-};
-
-static __init int walk_callback(void *ctx, const u8 *ip, u8 cidr, int family)
-{
-	struct walk_ctx *wctx = ctx;
-
-	wctx->count++;
-
-	if (cidr == 27 &&
-	    !memcmp(ip, ip4(192, 95, 5, 64), sizeof(struct in_addr)))
-		wctx->found_a = true;
-	else if (cidr == 128 &&
-		 !memcmp(ip, ip6(0x26075300, 0x60006b00, 0, 0xc05f0543),
-			 sizeof(struct in6_addr)))
-		wctx->found_b = true;
-	else if (cidr == 29 &&
-		 !memcmp(ip, ip4(10, 1, 0, 16), sizeof(struct in_addr)))
-		wctx->found_c = true;
-	else if (cidr == 83 &&
-		 !memcmp(ip, ip6(0x26075300, 0x6d8a6bf8, 0xdab1e000, 0),
-			 sizeof(struct in6_addr)))
-		wctx->found_d = true;
-	else if (cidr == 21 &&
-		 !memcmp(ip, ip6(0x26075000, 0, 0, 0), sizeof(struct in6_addr)))
-		wctx->found_e = true;
-	else
-		wctx->found_other = true;
-
-	return 0;
-}
-
 static __init struct wg_peer *init_peer(void)
 {
 	struct wg_peer *peer = kzalloc(sizeof(*peer), GFP_KERNEL);
 
-	if (peer)
-		kref_init(&peer->refcount);
+	if (!peer)
+		return NULL;
+	kref_init(&peer->refcount);
+	INIT_LIST_HEAD(&peer->allowedips_list);
 	return peer;
 }
 
@@ -527,23 +494,24 @@ static __init struct wg_peer *init_peer(void)
 
 bool __init wg_allowedips_selftest(void)
 {
-	struct allowedips_cursor *cursor = kzalloc(sizeof(*cursor), GFP_KERNEL);
+	bool found_a = false, found_b = false, found_c = false, found_d = false,
+	     found_e = false, found_other = false;
 	struct wg_peer *a = init_peer(), *b = init_peer(), *c = init_peer(),
 		       *d = init_peer(), *e = init_peer(), *f = init_peer(),
 		       *g = init_peer(), *h = init_peer();
-	struct walk_ctx wctx = { 0 };
+	struct allowedips_node *iter_node;
 	bool success = false;
 	struct allowedips t;
 	DEFINE_MUTEX(mutex);
 	struct in6_addr ip;
-	size_t i = 0;
+	size_t i = 0, count = 0;
 	__be64 part;
 
 	mutex_init(&mutex);
 	mutex_lock(&mutex);
 	wg_allowedips_init(&t);
 
-	if (!cursor || !a || !b || !c || !d || !e || !f || !g || !h) {
+	if (!a || !b || !c || !d || !e || !f || !g || !h) {
 		pr_err("allowedips self-test malloc: FAIL\n");
 		goto free;
 	}
@@ -649,14 +617,40 @@ bool __init wg_allowedips_selftest(void)
 	insert(4, a, 10, 1, 0, 20, 29);
 	insert(6, a, 0x26075300, 0x6d8a6bf8, 0xdab1f1df, 0xc05f1523, 83);
 	insert(6, a, 0x26075300, 0x6d8a6bf8, 0xdab1f1df, 0xc05f1523, 21);
-	wg_allowedips_walk_by_peer(&t, cursor, a, walk_callback, &wctx, &mutex);
-	test_boolean(wctx.count == 5);
-	test_boolean(wctx.found_a);
-	test_boolean(wctx.found_b);
-	test_boolean(wctx.found_c);
-	test_boolean(wctx.found_d);
-	test_boolean(wctx.found_e);
-	test_boolean(!wctx.found_other);
+	list_for_each_entry(iter_node, &a->allowedips_list, peer_list) {
+		u8 cidr, ip[16] __aligned(__alignof(u64));
+		int family = wg_allowedips_read_node(iter_node, ip, &cidr);
+
+		count++;
+
+		if (cidr == 27 && family == AF_INET &&
+		    !memcmp(ip, ip4(192, 95, 5, 64), sizeof(struct in_addr)))
+			found_a = true;
+		else if (cidr == 128 && family == AF_INET6 &&
+			 !memcmp(ip, ip6(0x26075300, 0x60006b00, 0, 0xc05f0543),
+				 sizeof(struct in6_addr)))
+			found_b = true;
+		else if (cidr == 29 && family == AF_INET &&
+			 !memcmp(ip, ip4(10, 1, 0, 16), sizeof(struct in_addr)))
+			found_c = true;
+		else if (cidr == 83 && family == AF_INET6 &&
+			 !memcmp(ip, ip6(0x26075300, 0x6d8a6bf8, 0xdab1e000, 0),
+				 sizeof(struct in6_addr)))
+			found_d = true;
+		else if (cidr == 21 && family == AF_INET6 &&
+			 !memcmp(ip, ip6(0x26075000, 0, 0, 0),
+				 sizeof(struct in6_addr)))
+			found_e = true;
+		else
+			found_other = true;
+	}
+	test_boolean(count == 5);
+	test_boolean(found_a);
+	test_boolean(found_b);
+	test_boolean(found_c);
+	test_boolean(found_d);
+	test_boolean(found_e);
+	test_boolean(!found_other);
 
 	if (IS_ENABLED(DEBUG_RANDOM_TRIE) && success)
 		success = randomized_test();
@@ -675,7 +669,6 @@ free:
 	kfree(g);
 	kfree(h);
 	mutex_unlock(&mutex);
-	kfree(cursor);
 
 	return success;
 }