diff options
Diffstat (limited to 'src/allowedips.c')
-rw-r--r-- | src/allowedips.c | 148 |
1 files changed, 99 insertions, 49 deletions
diff --git a/src/allowedips.c b/src/allowedips.c index 1442bf4..4616645 100644 --- a/src/allowedips.c +++ b/src/allowedips.c @@ -28,7 +28,8 @@ static __always_inline void swap_endian(u8 *dst, const u8 *src, u8 bits) } } -static void copy_and_assign_cidr(struct allowedips_node *node, const u8 *src, u8 cidr, u8 bits) +static void copy_and_assign_cidr(struct allowedips_node *node, const u8 *src, + u8 cidr, u8 bits) { node->cidr = cidr; node->bit_at_a = cidr / 8U; @@ -39,34 +40,43 @@ static void copy_and_assign_cidr(struct allowedips_node *node, const u8 *src, u8 memcpy(node->bits, src, bits / 8U); } -#define choose_node(parent, key) parent->bit[(key[parent->bit_at_a] >> parent->bit_at_b) & 1] +#define choose_node(parent, key) \ + parent->bit[(key[parent->bit_at_a] >> parent->bit_at_b) & 1] static void node_free_rcu(struct rcu_head *rcu) { kfree(container_of(rcu, struct allowedips_node, rcu)); } -#define push_rcu(stack, p, len) ({ \ - if (rcu_access_pointer(p)) { \ - BUG_ON(len >= 128); \ - stack[len++] = rcu_dereference_raw(p); \ - } \ - true; \ -}) +#define push_rcu(stack, p, len) ({ \ + if (rcu_access_pointer(p)) { \ + BUG_ON(len >= 128); \ + stack[len++] = rcu_dereference_raw(p); \ + } \ + true; \ + }) static void root_free_rcu(struct rcu_head *rcu) { - struct allowedips_node *node, *stack[128] = { container_of(rcu, struct allowedips_node, rcu) }; + struct allowedips_node *node, *stack[128] = + { container_of(rcu, struct allowedips_node, rcu) }; unsigned int len = 1; - while (len > 0 && (node = stack[--len]) && push_rcu(stack, node->bit[0], len) && push_rcu(stack, node->bit[1], len)) + while (len > 0 && (node = stack[--len]) && + push_rcu(stack, node->bit[0], len) && + push_rcu(stack, node->bit[1], len)) kfree(node); } -static int walk_by_peer(struct allowedips_node __rcu *top, u8 bits, struct allowedips_cursor *cursor, struct wireguard_peer *peer, int (*func)(void *ctx, const u8 *ip, u8 cidr, int family), void *ctx, struct mutex *lock) +static int +walk_by_peer(struct allowedips_node __rcu *top, u8 bits, + struct allowedips_cursor *cursor, struct wireguard_peer *peer, + int (*func)(void *ctx, const u8 *ip, u8 cidr, int family), + void *ctx, struct mutex *lock) { + const int address_family = bits == 32 ? AF_INET : AF_INET6; + u8 ip[16] __aligned(__alignof(u64)); struct allowedips_node *node; int ret; - u8 ip[16] __aligned(__alignof(u64)); if (!rcu_access_pointer(top)) return 0; @@ -74,16 +84,21 @@ static int walk_by_peer(struct allowedips_node __rcu *top, u8 bits, struct allow if (!cursor->len) push_rcu(cursor->stack, top, cursor->len); - for (; cursor->len > 0 && (node = cursor->stack[cursor->len - 1]); --cursor->len, push_rcu(cursor->stack, node->bit[0], cursor->len), push_rcu(cursor->stack, node->bit[1], cursor->len)) { - if (rcu_dereference_protected(node->peer, lockdep_is_held(lock)) != peer) + for (; cursor->len > 0 && (node = cursor->stack[cursor->len - 1]); + --cursor->len, push_rcu(cursor->stack, node->bit[0], cursor->len), + push_rcu(cursor->stack, node->bit[1], cursor->len)) { + const unsigned int cidr_bytes = DIV_ROUND_UP(node->cidr, 8U); + + if (rcu_dereference_protected(node->peer, + lockdep_is_held(lock)) != peer) continue; swap_endian(ip, node->bits, bits); - memset(ip + (node->cidr + 7U) / 8U, 0, (bits / 8U) - ((node->cidr + 7U) / 8U)); + memset(ip + cidr_bytes, 0, bits / 8U - cidr_bytes); if (node->cidr) - ip[(node->cidr + 7U) / 8U - 1U] &= ~0U << (-node->cidr % 8U); + ip[cidr_bytes - 1U] &= ~0U << (-node->cidr % 8U); - ret = func(ctx, ip, node->cidr, bits == 32 ? AF_INET : AF_INET6); + ret = func(ctx, ip, node->cidr, address_family); if (ret) return ret; } @@ -93,8 +108,12 @@ static int walk_by_peer(struct allowedips_node __rcu *top, u8 bits, struct allow #define ref(p) rcu_access_pointer(p) #define deref(p) rcu_dereference_protected(*p, lockdep_is_held(lock)) -#define push(p) ({ BUG_ON(len >= 128); stack[len++] = p; }) -static void walk_remove_by_peer(struct allowedips_node __rcu **top, struct wireguard_peer *peer, struct mutex *lock) +#define push(p) ({ \ + BUG_ON(len >= 128); \ + stack[len++] = p; \ + }) +static void walk_remove_by_peer(struct allowedips_node __rcu **top, + struct wireguard_peer *peer, struct mutex *lock) { struct allowedips_node __rcu **stack[128], **nptr; struct allowedips_node *node, *prev; @@ -110,7 +129,8 @@ static void walk_remove_by_peer(struct allowedips_node __rcu **top, struct wireg --len; continue; } - if (!prev || ref(prev->bit[0]) == node || ref(prev->bit[1]) == node) { + if (!prev || ref(prev->bit[0]) == node || + ref(prev->bit[1]) == node) { if (ref(node->bit[0])) push(&node->bit[0]); else if (ref(node->bit[1])) @@ -119,10 +139,12 @@ static void walk_remove_by_peer(struct allowedips_node __rcu **top, struct wireg if (ref(node->bit[1])) push(&node->bit[1]); } else { - if (rcu_dereference_protected(node->peer, lockdep_is_held(lock)) == peer) { + if (rcu_dereference_protected(node->peer, + lockdep_is_held(lock)) == peer) { RCU_INIT_POINTER(node->peer, NULL); if (!node->bit[0] || !node->bit[1]) { - rcu_assign_pointer(*nptr, deref(&node->bit[!ref(node->bit[0])])); + rcu_assign_pointer(*nptr, + deref(&node->bit[!ref(node->bit[0])])); call_rcu_bh(&node->rcu, node_free_rcu); node = deref(nptr); } @@ -140,23 +162,29 @@ static __always_inline unsigned int fls128(u64 a, u64 b) return a ? fls64(a) + 64U : fls64(b); } -static __always_inline u8 common_bits(const struct allowedips_node *node, const u8 *key, u8 bits) +static __always_inline u8 common_bits(const struct allowedips_node *node, + const u8 *key, u8 bits) { if (bits == 32) return 32U - fls(*(const u32 *)node->bits ^ *(const u32 *)key); else if (bits == 128) - return 128U - fls128(*(const u64 *)&node->bits[0] ^ *(const u64 *)&key[0], *(const u64 *)&node->bits[8] ^ *(const u64 *)&key[8]); + return 128U - fls128( + *(const u64 *)&node->bits[0] ^ *(const u64 *)&key[0], + *(const u64 *)&node->bits[8] ^ *(const u64 *)&key[8]); return 0; } -/* This could be much faster if it actually just compared the common bits properly, - * by precomputing a mask bswap(~0 << (32 - cidr)), and the rest, but it turns out that - * common_bits is already super fast on modern processors, even taking into account - * the unfortunate bswap. So, we just inline it like this instead. +/* This could be much faster if it actually just compared the common bits + * properly, by precomputing a mask bswap(~0 << (32 - cidr)), and the rest, but + * it turns out that common_bits is already super fast on modern processors, + * even taking into account the unfortunate bswap. So, we just inline it like + * this instead. */ -#define prefix_matches(node, key, bits) (common_bits(node, key, bits) >= node->cidr) +#define prefix_matches(node, key, bits) \ + (common_bits(node, key, bits) >= node->cidr) -static __always_inline struct allowedips_node *find_node(struct allowedips_node *trie, u8 bits, const u8 *key) +static __always_inline struct allowedips_node * +find_node(struct allowedips_node *trie, u8 bits, const u8 *key) { struct allowedips_node *node = trie, *found = NULL; @@ -171,11 +199,12 @@ static __always_inline struct allowedips_node *find_node(struct allowedips_node } /* Returns a strong reference to a peer */ -static __always_inline struct wireguard_peer *lookup(struct allowedips_node __rcu *root, u8 bits, const void *be_ip) +static __always_inline struct wireguard_peer * +lookup(struct allowedips_node __rcu *root, u8 bits, const void *be_ip) { + u8 ip[16] __aligned(__alignof(u64)); struct wireguard_peer *peer = NULL; struct allowedips_node *node; - u8 ip[16] __aligned(__alignof(u64)); swap_endian(ip, be_ip, bits); @@ -191,11 +220,14 @@ retry: return peer; } -__attribute__((nonnull(1))) -static inline bool node_placement(struct allowedips_node __rcu *trie, const u8 *key, u8 cidr, u8 bits, struct allowedips_node **rnode, struct mutex *lock) +__attribute__((nonnull(1))) static inline bool +node_placement(struct allowedips_node __rcu *trie, const u8 *key, u8 cidr, + u8 bits, struct allowedips_node **rnode, struct mutex *lock) { + struct allowedips_node *node = rcu_dereference_protected(trie, + lockdep_is_held(lock)); + struct allowedips_node *parent = NULL; bool exact = false; - struct allowedips_node *parent = NULL, *node = rcu_dereference_protected(trie, lockdep_is_held(lock)); while (node && node->cidr <= cidr && prefix_matches(node, key, bits)) { parent = node; @@ -203,13 +235,15 @@ static inline bool node_placement(struct allowedips_node __rcu *trie, const u8 * exact = true; break; } - node = rcu_dereference_protected(choose_node(parent, key), lockdep_is_held(lock)); + node = rcu_dereference_protected(choose_node(parent, key), + lockdep_is_held(lock)); } *rnode = parent; return exact; } -static int add(struct allowedips_node __rcu **trie, u8 bits, const u8 *be_key, u8 cidr, struct wireguard_peer *peer, struct mutex *lock) +static int add(struct allowedips_node __rcu **trie, u8 bits, const u8 *be_key, + u8 cidr, struct wireguard_peer *peer, struct mutex *lock) { struct allowedips_node *node, *parent, *down, *newnode; u8 key[16] __aligned(__alignof(u64)); @@ -242,7 +276,8 @@ static int add(struct allowedips_node __rcu **trie, u8 bits, const u8 *be_key, u if (!node) down = rcu_dereference_protected(*trie, lockdep_is_held(lock)); else { - down = rcu_dereference_protected(choose_node(node, key), lockdep_is_held(lock)); + down = rcu_dereference_protected(choose_node(node, key), + lockdep_is_held(lock)); if (!down) { rcu_assign_pointer(choose_node(node, key), newnode); return 0; @@ -256,7 +291,8 @@ static int add(struct allowedips_node __rcu **trie, u8 bits, const u8 *be_key, u if (!parent) rcu_assign_pointer(*trie, newnode); else - rcu_assign_pointer(choose_node(parent, newnode->bits), newnode); + rcu_assign_pointer(choose_node(parent, newnode->bits), + newnode); } else { node = kzalloc(sizeof(*node), GFP_KERNEL); if (!node) { @@ -270,7 +306,8 @@ static int add(struct allowedips_node __rcu **trie, u8 bits, const u8 *be_key, u if (!parent) rcu_assign_pointer(*trie, node); else - rcu_assign_pointer(choose_node(parent, node->bits), node); + rcu_assign_pointer(choose_node(parent, node->bits), + node); } return 0; } @@ -288,31 +325,42 @@ void allowedips_free(struct allowedips *table, struct mutex *lock) RCU_INIT_POINTER(table->root4, NULL); RCU_INIT_POINTER(table->root6, NULL); if (rcu_access_pointer(old4)) - call_rcu_bh(&rcu_dereference_protected(old4, lockdep_is_held(lock))->rcu, root_free_rcu); + call_rcu_bh(&rcu_dereference_protected(old4, + lockdep_is_held(lock))->rcu, root_free_rcu); if (rcu_access_pointer(old6)) - call_rcu_bh(&rcu_dereference_protected(old6, lockdep_is_held(lock))->rcu, root_free_rcu); + call_rcu_bh(&rcu_dereference_protected(old6, + lockdep_is_held(lock))->rcu, root_free_rcu); } -int allowedips_insert_v4(struct allowedips *table, const struct in_addr *ip, u8 cidr, struct wireguard_peer *peer, struct mutex *lock) +int allowedips_insert_v4(struct allowedips *table, const struct in_addr *ip, + u8 cidr, struct wireguard_peer *peer, + struct mutex *lock) { ++table->seq; return add(&table->root4, 32, (const u8 *)ip, cidr, peer, lock); } -int allowedips_insert_v6(struct allowedips *table, const struct in6_addr *ip, u8 cidr, struct wireguard_peer *peer, struct mutex *lock) +int allowedips_insert_v6(struct allowedips *table, const struct in6_addr *ip, + u8 cidr, struct wireguard_peer *peer, + struct mutex *lock) { ++table->seq; return add(&table->root6, 128, (const u8 *)ip, cidr, peer, lock); } -void allowedips_remove_by_peer(struct allowedips *table, struct wireguard_peer *peer, struct mutex *lock) +void allowedips_remove_by_peer(struct allowedips *table, + struct wireguard_peer *peer, struct mutex *lock) { ++table->seq; walk_remove_by_peer(&table->root4, peer, lock); walk_remove_by_peer(&table->root6, peer, lock); } -int allowedips_walk_by_peer(struct allowedips *table, struct allowedips_cursor *cursor, struct wireguard_peer *peer, int (*func)(void *ctx, const u8 *ip, u8 cidr, int family), void *ctx, struct mutex *lock) +int allowedips_walk_by_peer(struct allowedips *table, + struct allowedips_cursor *cursor, + struct wireguard_peer *peer, + int (*func)(void *ctx, const u8 *ip, u8 cidr, int family), + void *ctx, struct mutex *lock) { int ret; @@ -332,7 +380,8 @@ int allowedips_walk_by_peer(struct allowedips *table, struct allowedips_cursor * } /* Returns a strong reference to a peer */ -struct wireguard_peer *allowedips_lookup_dst(struct allowedips *table, struct sk_buff *skb) +struct wireguard_peer *allowedips_lookup_dst(struct allowedips *table, + struct sk_buff *skb) { if (skb->protocol == htons(ETH_P_IP)) return lookup(table->root4, 32, &ip_hdr(skb)->daddr); @@ -342,7 +391,8 @@ struct wireguard_peer *allowedips_lookup_dst(struct allowedips *table, struct sk } /* Returns a strong reference to a peer */ -struct wireguard_peer *allowedips_lookup_src(struct allowedips *table, struct sk_buff *skb) +struct wireguard_peer *allowedips_lookup_src(struct allowedips *table, + struct sk_buff *skb) { if (skb->protocol == htons(ETH_P_IP)) return lookup(table->root4, 32, &ip_hdr(skb)->saddr); 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