#define __IPSEC_SPD_SA_H__
#include <vlib/vlib.h>
+#include <vppinfra/pcg.h>
+#include <vnet/crypto/crypto.h>
#include <vnet/ip/ip.h>
#include <vnet/fib/fib_node.h>
-
-#define IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE (64)
-
-#define foreach_ipsec_crypto_alg \
- _ (0, NONE, "none") \
- _ (1, AES_CBC_128, "aes-cbc-128") \
- _ (2, AES_CBC_192, "aes-cbc-192") \
- _ (3, AES_CBC_256, "aes-cbc-256") \
- _ (4, AES_CTR_128, "aes-ctr-128") \
- _ (5, AES_CTR_192, "aes-ctr-192") \
- _ (6, AES_CTR_256, "aes-ctr-256") \
- _ (7, AES_GCM_128, "aes-gcm-128") \
- _ (8, AES_GCM_192, "aes-gcm-192") \
- _ (9, AES_GCM_256, "aes-gcm-256") \
- _ (10, DES_CBC, "des-cbc") \
- _ (11, 3DES_CBC, "3des-cbc")
+#include <vnet/tunnel/tunnel.h>
+
+#define ESP_MAX_ICV_SIZE (32)
+#define ESP_MAX_IV_SIZE (16)
+#define ESP_MAX_BLOCK_SIZE (16)
+
+#define foreach_ipsec_crypto_alg \
+ _ (0, NONE, "none") \
+ _ (1, AES_CBC_128, "aes-cbc-128") \
+ _ (2, AES_CBC_192, "aes-cbc-192") \
+ _ (3, AES_CBC_256, "aes-cbc-256") \
+ _ (4, AES_CTR_128, "aes-ctr-128") \
+ _ (5, AES_CTR_192, "aes-ctr-192") \
+ _ (6, AES_CTR_256, "aes-ctr-256") \
+ _ (7, AES_GCM_128, "aes-gcm-128") \
+ _ (8, AES_GCM_192, "aes-gcm-192") \
+ _ (9, AES_GCM_256, "aes-gcm-256") \
+ _ (10, DES_CBC, "des-cbc") \
+ _ (11, 3DES_CBC, "3des-cbc") \
+ _ (12, CHACHA20_POLY1305, "chacha20-poly1305") \
+ _ (13, AES_NULL_GMAC_128, "aes-null-gmac-128") \
+ _ (14, AES_NULL_GMAC_192, "aes-null-gmac-192") \
+ _ (15, AES_NULL_GMAC_256, "aes-null-gmac-256")
typedef enum
{
foreach_ipsec_crypto_alg
#undef _
IPSEC_CRYPTO_N_ALG,
-} ipsec_crypto_alg_t;
+} __clib_packed ipsec_crypto_alg_t;
+
+#define IPSEC_CRYPTO_ALG_IS_NULL_GMAC(_alg) \
+ ((_alg == IPSEC_CRYPTO_ALG_AES_NULL_GMAC_128) || \
+ (_alg == IPSEC_CRYPTO_ALG_AES_NULL_GMAC_192) || \
+ (_alg == IPSEC_CRYPTO_ALG_AES_NULL_GMAC_256))
#define IPSEC_CRYPTO_ALG_IS_GCM(_alg) \
(((_alg == IPSEC_CRYPTO_ALG_AES_GCM_128) || \
(_alg == IPSEC_CRYPTO_ALG_AES_GCM_192) || \
(_alg == IPSEC_CRYPTO_ALG_AES_GCM_256)))
+#define IPSEC_CRYPTO_ALG_IS_CTR(_alg) \
+ (((_alg == IPSEC_CRYPTO_ALG_AES_CTR_128) || \
+ (_alg == IPSEC_CRYPTO_ALG_AES_CTR_192) || \
+ (_alg == IPSEC_CRYPTO_ALG_AES_CTR_256)))
+
+#define IPSEC_CRYPTO_ALG_CTR_AEAD_OTHERS(_alg) \
+ (_alg == IPSEC_CRYPTO_ALG_CHACHA20_POLY1305)
+
#define foreach_ipsec_integ_alg \
_ (0, NONE, "none") \
_ (1, MD5_96, "md5-96") /* RFC2403 */ \
foreach_ipsec_integ_alg
#undef _
IPSEC_INTEG_N_ALG,
-} ipsec_integ_alg_t;
+} __clib_packed ipsec_integ_alg_t;
typedef enum
{
IPSEC_PROTOCOL_AH = 0,
IPSEC_PROTOCOL_ESP = 1
-} ipsec_protocol_t;
-
-#define IPSEC_N_PROTOCOLS (IPSEC_PROTOCOL_ESP+1)
+} __clib_packed ipsec_protocol_t;
#define IPSEC_KEY_MAX_LEN 128
typedef struct ipsec_key_t_
* else IPv4 tunnel only valid if is_tunnel is non-zero
* enable UDP encapsulation for NAT traversal
*/
-#define foreach_ipsec_sa_flags \
- _ (0, NONE, "none") \
- _ (1, USE_ESN, "esn") \
- _ (2, USE_ANTI_REPLAY, "anti-replay") \
- _ (4, IS_TUNNEL, "tunnel") \
- _ (8, IS_TUNNEL_V6, "tunnel-v6") \
- _ (16, UDP_ENCAP, "udp-encap") \
- _ (32, IS_GRE, "GRE") \
- _ (64, IS_INBOUND, "inboud") \
- _ (128, IS_AEAD, "aead") \
+#define foreach_ipsec_sa_flags \
+ _ (0, NONE, "none") \
+ _ (1, USE_ESN, "esn") \
+ _ (2, USE_ANTI_REPLAY, "anti-replay") \
+ _ (4, IS_TUNNEL, "tunnel") \
+ _ (8, IS_TUNNEL_V6, "tunnel-v6") \
+ _ (16, UDP_ENCAP, "udp-encap") \
+ _ (32, IS_PROTECT, "Protect") \
+ _ (64, IS_INBOUND, "inbound") \
+ _ (128, IS_AEAD, "aead") \
+ _ (256, IS_CTR, "ctr") \
+ _ (512, IS_ASYNC, "async") \
+ _ (1024, NO_ALGO_NO_DROP, "no-algo-no-drop") \
+ _ (2048, IS_NULL_GMAC, "null-gmac") \
+ _ (4096, ANTI_REPLAY_HUGE, "anti-replay-huge")
typedef enum ipsec_sad_flags_t_
{
#undef _
} __clib_packed ipsec_sa_flags_t;
-STATIC_ASSERT (sizeof (ipsec_sa_flags_t) == 1, "IPSEC SA flags > 1 byte");
+STATIC_ASSERT (sizeof (ipsec_sa_flags_t) == 2, "IPSEC SA flags != 2 byte");
+
+#define foreach_ipsec_sa_err \
+ _ (0, LOST, lost, "packets lost") \
+ _ (1, HANDOFF, handoff, "hand-off") \
+ _ (2, INTEG_ERROR, integ_error, "Integrity check failed") \
+ _ (3, DECRYPTION_FAILED, decryption_failed, "Decryption failed") \
+ _ (4, CRYPTO_ENGINE_ERROR, crypto_engine_error, \
+ "crypto engine error (dropped)") \
+ _ (5, REPLAY, replay, "SA replayed packet") \
+ _ (6, RUNT, runt, "undersized packet") \
+ _ (7, NO_BUFFERS, no_buffers, "no buffers (dropped)") \
+ _ (8, OVERSIZED_HEADER, oversized_header, \
+ "buffer with oversized header (dropped)") \
+ _ (9, NO_TAIL_SPACE, no_tail_space, \
+ "no enough buffer tail space (dropped)") \
+ _ (10, TUN_NO_PROTO, tun_no_proto, "no tunnel protocol") \
+ _ (11, UNSUP_PAYLOAD, unsup_payload, "unsupported payload") \
+ _ (12, SEQ_CYCLED, seq_cycled, "sequence number cycled (dropped)") \
+ _ (13, CRYPTO_QUEUE_FULL, crypto_queue_full, "crypto queue full (dropped)") \
+ _ (14, NO_ENCRYPTION, no_encryption, "no Encrypting SA (dropped)") \
+ _ (15, DROP_FRAGMENTS, drop_fragments, "IP fragments drop")
+
+typedef enum
+{
+#define _(v, f, s, d) IPSEC_SA_ERROR_##f = v,
+ foreach_ipsec_sa_err
+#undef _
+ IPSEC_SA_N_ERRORS,
+} __clib_packed ipsec_sa_err_t;
typedef struct
{
CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
- /* flags */
- ipsec_sa_flags_t flags;
+ clib_pcg64i_random_t iv_prng;
+
+ union
+ {
+ u64 replay_window;
+ clib_bitmap_t *replay_window_huge;
+ };
+ dpo_id_t dpo;
+
+ vnet_crypto_key_index_t crypto_key_index;
+ vnet_crypto_key_index_t integ_key_index;
- u8 crypto_iv_size;
- u8 crypto_block_size;
- u8 integ_icv_size;
u32 spi;
u32 seq;
u32 seq_hi;
- u32 last_seq;
- u32 last_seq_hi;
- u64 replay_window;
- vnet_crypto_key_index_t crypto_key_index;
- vnet_crypto_key_index_t integ_key_index;
- vnet_crypto_op_id_t crypto_enc_op_id:16;
- vnet_crypto_op_id_t crypto_dec_op_id:16;
- vnet_crypto_op_id_t integ_op_id:16;
+ u16 crypto_enc_op_id;
+ u16 crypto_dec_op_id;
+ u16 integ_op_id;
+ ipsec_sa_flags_t flags;
+ u16 thread_index;
- dpo_id_t dpo[IPSEC_N_PROTOCOLS];
+ u16 integ_icv_size : 6;
+ u16 crypto_iv_size : 5;
+ u16 esp_block_align : 5;
- /* data accessed by dataplane code should be above this comment */
- CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
+ CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
union
{
};
udp_header_t udp_hdr;
+ /* Salt used in CTR modes (incl. GCM) - stored in network byte order */
+ u32 salt;
+ ipsec_protocol_t protocol;
+ tunnel_encap_decap_flags_t tunnel_flags;
+ u8 __pad[2];
+
+ /* data accessed by dataplane code should be above this comment */
+ CLIB_CACHE_LINE_ALIGN_MARK (cacheline2);
+
+ /* Elements with u64 size multiples */
+ tunnel_t tunnel;
fib_node_t node;
+
+ /* elements with u32 size */
u32 id;
u32 stat_index;
- ipsec_protocol_t protocol;
-
- ipsec_crypto_alg_t crypto_alg;
- ipsec_key_t crypto_key;
+ vnet_crypto_alg_t integ_calg;
vnet_crypto_alg_t crypto_calg;
-
+ u32 crypto_sync_key_index;
+ u32 integ_sync_key_index;
+ u32 crypto_async_key_index;
+
+ /* elements with u16 size */
+ u16 crypto_sync_enc_op_id;
+ u16 crypto_sync_dec_op_id;
+ u16 integ_sync_op_id;
+ u16 crypto_async_enc_op_id;
+ u16 crypto_async_dec_op_id;
+
+ /* else u8 packed */
+ ipsec_crypto_alg_t crypto_alg;
ipsec_integ_alg_t integ_alg;
- ipsec_key_t integ_key;
- vnet_crypto_alg_t integ_calg;
- ip46_address_t tunnel_src_addr;
- ip46_address_t tunnel_dst_addr;
-
- fib_node_index_t fib_entry_index;
- u32 sibling;
-
- u32 tx_fib_index;
-
- /* Salt used in GCM modes - stored in network byte order */
- u32 salt;
- u64 gcm_iv_counter;
+ ipsec_key_t integ_key;
+ ipsec_key_t crypto_key;
} ipsec_sa_t;
+STATIC_ASSERT (VNET_CRYPTO_N_OP_IDS < (1 << 16), "crypto ops overflow");
+STATIC_ASSERT (ESP_MAX_ICV_SIZE < (1 << 6), "integer icv overflow");
+STATIC_ASSERT (ESP_MAX_IV_SIZE < (1 << 5), "esp iv overflow");
+STATIC_ASSERT (ESP_MAX_BLOCK_SIZE < (1 << 5), "esp alignment overflow");
STATIC_ASSERT_OFFSET_OF (ipsec_sa_t, cacheline1, CLIB_CACHE_LINE_BYTES);
+STATIC_ASSERT_OFFSET_OF (ipsec_sa_t, cacheline2, 2 * CLIB_CACHE_LINE_BYTES);
+
+/**
+ * Pool of IPSec SAs
+ */
+extern ipsec_sa_t *ipsec_sa_pool;
-#define _(a,v,s) \
- always_inline int \
- ipsec_sa_is_set_##v (const ipsec_sa_t *sa) { \
- return (sa->flags & IPSEC_SA_FLAG_##v); \
+/*
+ * Ensure that the IPsec data does not overlap with the IP data in
+ * the buffer meta data
+ */
+STATIC_ASSERT (STRUCT_OFFSET_OF (vnet_buffer_opaque_t, ipsec.sad_index) ==
+ STRUCT_OFFSET_OF (vnet_buffer_opaque_t, ip.save_protocol),
+ "IPSec data is overlapping with IP data");
+
+#define _(a, v, s) \
+ always_inline bool ipsec_sa_is_set_##v (const ipsec_sa_t *sa) \
+ { \
+ return (sa->flags & IPSEC_SA_FLAG_##v); \
}
foreach_ipsec_sa_flags
#undef _
-#define _(a,v,s) \
- always_inline int \
- ipsec_sa_set_##v (ipsec_sa_t *sa) { \
- return (sa->flags |= IPSEC_SA_FLAG_##v); \
+#define _(a, v, s) \
+ always_inline void ipsec_sa_set_##v (ipsec_sa_t *sa) \
+ { \
+ sa->flags |= IPSEC_SA_FLAG_##v; \
}
foreach_ipsec_sa_flags
#undef _
-/**
- * @brief
- * SA packet & bytes counters
- */
-extern vlib_combined_counter_main_t ipsec_sa_counters;
-
-extern void ipsec_mk_key (ipsec_key_t * key, const u8 * data, u8 len);
-
-extern int ipsec_sa_add (u32 id,
- u32 spi,
- ipsec_protocol_t proto,
- ipsec_crypto_alg_t crypto_alg,
- const ipsec_key_t * ck,
- ipsec_integ_alg_t integ_alg,
- const ipsec_key_t * ik,
- ipsec_sa_flags_t flags,
- u32 tx_table_id,
- u32 salt,
- const ip46_address_t * tunnel_src_addr,
- const ip46_address_t * tunnel_dst_addr,
- u32 * sa_index);
-extern u32 ipsec_sa_del (u32 id);
-extern void ipsec_sa_set_crypto_alg (ipsec_sa_t * sa,
+#define _(a, v, s) \
+ always_inline int ipsec_sa_unset_##v (ipsec_sa_t *sa) \
+ { \
+ return (sa->flags &= ~IPSEC_SA_FLAG_##v); \
+ }
+ foreach_ipsec_sa_flags
+#undef _
+ /**
+ * @brief
+ * SA packet & bytes counters
+ */
+ extern vlib_combined_counter_main_t ipsec_sa_counters;
+extern vlib_simple_counter_main_t ipsec_sa_err_counters[IPSEC_SA_N_ERRORS];
+
+extern void ipsec_mk_key (ipsec_key_t *key, const u8 *data, u8 len);
+
+extern int ipsec_sa_update (u32 id, u16 src_port, u16 dst_port,
+ const tunnel_t *tun, bool is_tun);
+extern int ipsec_sa_add_and_lock (
+ u32 id, u32 spi, ipsec_protocol_t proto, ipsec_crypto_alg_t crypto_alg,
+ const ipsec_key_t *ck, ipsec_integ_alg_t integ_alg, const ipsec_key_t *ik,
+ ipsec_sa_flags_t flags, u32 salt, u16 src_port, u16 dst_port,
+ u32 anti_replay_window_size, const tunnel_t *tun, u32 *sa_out_index);
+extern int ipsec_sa_bind (u32 id, u32 worker, bool bind);
+extern index_t ipsec_sa_find_and_lock (u32 id);
+extern int ipsec_sa_unlock_id (u32 id);
+extern void ipsec_sa_unlock (index_t sai);
+extern void ipsec_sa_lock (index_t sai);
+extern void ipsec_sa_clear (index_t sai);
+extern void ipsec_sa_set_crypto_alg (ipsec_sa_t *sa,
ipsec_crypto_alg_t crypto_alg);
-extern void ipsec_sa_set_integ_alg (ipsec_sa_t * sa,
+extern void ipsec_sa_set_integ_alg (ipsec_sa_t *sa,
ipsec_integ_alg_t integ_alg);
+extern void ipsec_sa_set_async_mode (ipsec_sa_t *sa, int is_enabled);
-extern u8 ipsec_is_sa_used (u32 sa_index);
-extern int ipsec_set_sa_key (u32 id,
- const ipsec_key_t * ck, const ipsec_key_t * ik);
-extern u32 ipsec_get_sa_index_by_sa_id (u32 sa_id);
-
-typedef walk_rc_t (*ipsec_sa_walk_cb_t) (ipsec_sa_t * sa, void *ctx);
+typedef walk_rc_t (*ipsec_sa_walk_cb_t) (ipsec_sa_t *sa, void *ctx);
extern void ipsec_sa_walk (ipsec_sa_walk_cb_t cd, void *ctx);
-extern u8 *format_ipsec_crypto_alg (u8 * s, va_list * args);
-extern u8 *format_ipsec_integ_alg (u8 * s, va_list * args);
-extern u8 *format_ipsec_sa (u8 * s, va_list * args);
-extern u8 *format_ipsec_key (u8 * s, va_list * args);
-extern uword unformat_ipsec_crypto_alg (unformat_input_t * input,
- va_list * args);
-extern uword unformat_ipsec_integ_alg (unformat_input_t * input,
- va_list * args);
-extern uword unformat_ipsec_key (unformat_input_t * input, va_list * args);
+extern u8 *format_ipsec_replay_window (u8 *s, va_list *args);
+extern u8 *format_ipsec_crypto_alg (u8 *s, va_list *args);
+extern u8 *format_ipsec_integ_alg (u8 *s, va_list *args);
+extern u8 *format_ipsec_sa (u8 *s, va_list *args);
+extern u8 *format_ipsec_key (u8 *s, va_list *args);
+extern uword unformat_ipsec_crypto_alg (unformat_input_t *input,
+ va_list *args);
+extern uword unformat_ipsec_integ_alg (unformat_input_t *input, va_list *args);
+extern uword unformat_ipsec_key (unformat_input_t *input, va_list *args);
+
+#define IPSEC_UDP_PORT_NONE ((u16) ~0)
+
+/*
+ * Anti Replay definitions
+ */
+
+#define IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE(_sa) \
+ (u32) (PREDICT_FALSE (ipsec_sa_is_set_ANTI_REPLAY_HUGE (_sa)) ? \
+ clib_bitmap_bytes (_sa->replay_window_huge) * 8 : \
+ BITS (_sa->replay_window))
+
+#define IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE_KNOWN_WIN(_sa, _is_huge) \
+ (u32) (_is_huge ? clib_bitmap_bytes (_sa->replay_window_huge) * 8 : \
+ BITS (_sa->replay_window))
+
+#define IPSEC_SA_ANTI_REPLAY_WINDOW_N_SEEN(_sa) \
+ (u64) (PREDICT_FALSE (ipsec_sa_is_set_ANTI_REPLAY_HUGE (_sa)) ? \
+ clib_bitmap_count_set_bits (_sa->replay_window_huge) : \
+ count_set_bits (_sa->replay_window))
+
+#define IPSEC_SA_ANTI_REPLAY_WINDOW_N_SEEN_KNOWN_WIN(_sa, _is_huge) \
+ (u64) (_is_huge ? clib_bitmap_count_set_bits (_sa->replay_window_huge) : \
+ count_set_bits (_sa->replay_window))
+
+#define IPSEC_SA_ANTI_REPLAY_WINDOW_MAX_INDEX(_sa) \
+ (u32) (IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE (_sa) - 1)
+
+#define IPSEC_SA_ANTI_REPLAY_WINDOW_MAX_INDEX_KNOWN_WIN(_sa, _is_huge) \
+ (u32) (IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE (_sa, _is_huge) - 1)
+
+/*
+ * sequence number less than the lower bound are outside of the window
+ * From RFC4303 Appendix A:
+ * Bl = Tl - W + 1
+ */
+#define IPSEC_SA_ANTI_REPLAY_WINDOW_LOWER_BOUND(_sa) \
+ (u32) (_sa->seq - IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE (_sa) + 1)
+
+#define IPSEC_SA_ANTI_REPLAY_WINDOW_LOWER_BOUND_KNOWN_WIN(_sa, _is_huge) \
+ (u32) (_sa->seq - \
+ IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE_KNOWN_WIN (_sa, _is_huge) + 1)
+
+always_inline u64
+ipsec_sa_anti_replay_get_64b_window (const ipsec_sa_t *sa)
+{
+ if (!ipsec_sa_is_set_ANTI_REPLAY_HUGE (sa))
+ return sa->replay_window;
+
+ u64 w;
+ u32 window_size = IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE (sa);
+ u32 tl_win_index = sa->seq & (window_size - 1);
+
+ if (PREDICT_TRUE (tl_win_index >= 63))
+ return clib_bitmap_get_multiple (sa->replay_window_huge, tl_win_index - 63,
+ 64);
+
+ w = clib_bitmap_get_multiple_no_check (sa->replay_window_huge, 0,
+ tl_win_index + 1)
+ << (63 - tl_win_index);
+ w |= clib_bitmap_get_multiple_no_check (sa->replay_window_huge,
+ window_size - 63 + tl_win_index,
+ 63 - tl_win_index);
+ return w;
+}
+
+always_inline int
+ipsec_sa_anti_replay_check (const ipsec_sa_t *sa, u32 seq, bool ar_huge)
+{
+ u32 window_size = IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE_KNOWN_WIN (sa, ar_huge);
+
+ /* we assume that the packet is in the window.
+ * if the packet falls left (sa->seq - seq >= window size),
+ * the result is wrong */
+
+ if (ar_huge)
+ return clib_bitmap_get (sa->replay_window_huge, seq & (window_size - 1));
+ else
+ return (sa->replay_window >> (window_size + seq - sa->seq - 1)) & 1;
+
+ return 0;
+}
+
+/*
+ * Anti replay check.
+ * inputs need to be in host byte order.
+ *
+ * The function runs in two contexts. pre and post decrypt.
+ * Pre-decrypt it:
+ * 1 - determines if a packet is a replay - a simple check in the window
+ * 2 - returns the hi-seq number that should be used to decrypt.
+ * post-decrypt:
+ * Checks whether the packet is a replay or falls out of window
+ *
+ * This funcion should be called even without anti-replay enabled to ensure
+ * the high sequence number is set.
+ */
always_inline int
-ipsec_sa_anti_replay_check (ipsec_sa_t * sa, u32 * seqp)
+ipsec_sa_anti_replay_and_sn_advance (const ipsec_sa_t *sa, u32 seq,
+ u32 hi_seq_used, bool post_decrypt,
+ u32 *hi_seq_req, bool ar_huge)
{
- u32 seq, diff, tl, th;
- if ((sa->flags & IPSEC_SA_FLAG_USE_ANTI_REPLAY) == 0)
- return 0;
+ ASSERT ((post_decrypt == false) == (hi_seq_req != 0));
- seq = clib_net_to_host_u32 (*seqp);
+ u32 window_size = IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE_KNOWN_WIN (sa, ar_huge);
+ u32 window_lower_bound =
+ IPSEC_SA_ANTI_REPLAY_WINDOW_LOWER_BOUND_KNOWN_WIN (sa, ar_huge);
- if ((sa->flags & IPSEC_SA_FLAG_USE_ESN) == 0)
+ if (!ipsec_sa_is_set_USE_ESN (sa))
{
+ if (hi_seq_req)
+ /* no ESN, therefore the hi-seq is always 0 */
+ *hi_seq_req = 0;
- if (PREDICT_TRUE (seq > sa->last_seq))
+ if (!ipsec_sa_is_set_USE_ANTI_REPLAY (sa))
return 0;
- diff = sa->last_seq - seq;
+ if (PREDICT_TRUE (seq > sa->seq))
+ return 0;
- if (IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE > diff)
- return (sa->replay_window & (1ULL << diff)) ? 1 : 0;
- else
+ /* does the packet fall out on the left of the window */
+ if (sa->seq >= seq + window_size)
return 1;
- return 0;
+ return ipsec_sa_anti_replay_check (sa, seq, ar_huge);
}
- tl = sa->last_seq;
- th = sa->last_seq_hi;
- diff = tl - seq;
+ if (!ipsec_sa_is_set_USE_ANTI_REPLAY (sa))
+ {
+ /* there's no AR configured for this SA, but in order
+ * to know whether a packet has wrapped the hi ESN we need
+ * to know whether it is out of window. if we use the default
+ * lower bound then we are effectively forcing AR because
+ * out of window packets will get the increased hi seq number
+ * and will thus fail to decrypt. IOW we need a window to know
+ * if the SN has wrapped, but we don't want a window to check for
+ * anti replay. to resolve the contradiction we use a huge window.
+ * if the packet is not within 2^30 of the current SN, we'll consider
+ * it a wrap.
+ */
+ if (hi_seq_req)
+ {
+ if (seq >= sa->seq)
+ /* The packet's sequence number is larger that the SA's.
+ * that can't be a warp - unless we lost more than
+ * 2^32 packets ... how could we know? */
+ *hi_seq_req = sa->seq_hi;
+ else
+ {
+ /* The packet's SN is less than the SAs, so either the SN has
+ * wrapped or the SN is just old. */
+ if (sa->seq - seq > (1 << 30))
+ /* It's really really really old => it wrapped */
+ *hi_seq_req = sa->seq_hi + 1;
+ else
+ *hi_seq_req = sa->seq_hi;
+ }
+ }
+ /*
+ * else
+ * this is post-decrpyt and since it decrypted we accept it
+ */
+ return 0;
+ }
- if (PREDICT_TRUE (tl >= (IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE - 1)))
+ if (PREDICT_TRUE (sa->seq >= window_size - 1))
{
- if (seq >= (tl - IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE + 1))
+ /*
+ * the last sequence number VPP received is more than one
+ * window size greater than zero.
+ * Case A from RFC4303 Appendix A.
+ */
+ if (seq < window_lower_bound)
{
- sa->seq_hi = th;
- if (seq <= tl)
- return (sa->replay_window & (1ULL << diff)) ? 1 : 0;
+ /*
+ * the received sequence number is lower than the lower bound
+ * of the window, this could mean either a replay packet or that
+ * the high sequence number has wrapped. if it decrypts corrently
+ * then it's the latter.
+ */
+ if (post_decrypt)
+ {
+ if (hi_seq_used == sa->seq_hi)
+ /* the high sequence number used to succesfully decrypt this
+ * packet is the same as the last-sequence number of the SA.
+ * that means this packet did not cause a wrap.
+ * this packet is thus out of window and should be dropped */
+ return 1;
+ else
+ /* The packet decrypted with a different high sequence number
+ * to the SA, that means it is the wrap packet and should be
+ * accepted */
+ return 0;
+ }
else
- return 0;
+ {
+ /* pre-decrypt it might be the packet that causes a wrap, we
+ * need to decrypt it to find out */
+ if (hi_seq_req)
+ *hi_seq_req = sa->seq_hi + 1;
+ return 0;
+ }
}
else
{
- sa->seq_hi = th + 1;
- return 0;
+ /*
+ * the received sequence number greater than the low
+ * end of the window.
+ */
+ if (hi_seq_req)
+ *hi_seq_req = sa->seq_hi;
+ if (seq <= sa->seq)
+ /*
+ * The received seq number is within bounds of the window
+ * check if it's a duplicate
+ */
+ return ipsec_sa_anti_replay_check (sa, seq, ar_huge);
+ else
+ /*
+ * The received sequence number is greater than the window
+ * upper bound. this packet will move the window along, assuming
+ * it decrypts correctly.
+ */
+ return 0;
}
}
else
{
- if (seq >= (tl - IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE + 1))
+ /*
+ * the last sequence number VPP received is within one window
+ * size of zero, i.e. 0 < TL < WINDOW_SIZE, the lower bound is thus a
+ * large sequence number.
+ * Note that the check below uses unsigned integer arithmetic, so the
+ * RHS will be a larger number.
+ * Case B from RFC4303 Appendix A.
+ */
+ if (seq < window_lower_bound)
{
- sa->seq_hi = th - 1;
- return (sa->replay_window & (1ULL << diff)) ? 1 : 0;
+ /*
+ * the sequence number is less than the lower bound.
+ */
+ if (seq <= sa->seq)
+ {
+ /*
+ * the packet is within the window upper bound.
+ * check for duplicates.
+ */
+ if (hi_seq_req)
+ *hi_seq_req = sa->seq_hi;
+ return ipsec_sa_anti_replay_check (sa, seq, ar_huge);
+ }
+ else
+ {
+ /*
+ * the packet is less the window lower bound or greater than
+ * the higher bound, depending on how you look at it...
+ * We're assuming, given that the last sequence number received,
+ * TL < WINDOW_SIZE, that a larger seq num is more likely to be
+ * a packet that moves the window forward, than a packet that has
+ * wrapped the high sequence again. If it were the latter then
+ * we've lost close to 2^32 packets.
+ */
+ if (hi_seq_req)
+ *hi_seq_req = sa->seq_hi;
+ return 0;
+ }
}
else
{
- sa->seq_hi = th;
- if (seq <= tl)
- return (sa->replay_window & (1ULL << diff)) ? 1 : 0;
- else
- return 0;
+ /*
+ * the packet seq number is between the lower bound (a large number)
+ * and MAX_SEQ_NUM. This is in the window since the window upper
+ * bound tl > 0. However, since TL is the other side of 0 to the
+ * received packet, the SA has moved on to a higher sequence number.
+ */
+ if (hi_seq_req)
+ *hi_seq_req = sa->seq_hi - 1;
+ return ipsec_sa_anti_replay_check (sa, seq, ar_huge);
}
}
+ /* unhandled case */
+ ASSERT (0);
return 0;
}
-always_inline void
-ipsec_sa_anti_replay_advance (ipsec_sa_t * sa, u32 * seqp)
+always_inline u32
+ipsec_sa_anti_replay_window_shift (ipsec_sa_t *sa, u32 inc, bool ar_huge)
{
- u32 pos, seq;
- if (PREDICT_TRUE (sa->flags & IPSEC_SA_FLAG_USE_ANTI_REPLAY) == 0)
- return;
+ u32 n_lost = 0;
+ u32 seen = 0;
+ u32 window_size = IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE_KNOWN_WIN (sa, ar_huge);
- seq = clib_host_to_net_u32 (*seqp);
- if (PREDICT_TRUE (sa->flags & IPSEC_SA_FLAG_USE_ESN))
+ if (inc < window_size)
{
- int wrap = sa->seq_hi - sa->last_seq_hi;
-
- if (wrap == 0 && seq > sa->last_seq)
+ if (ar_huge)
{
- pos = seq - sa->last_seq;
- if (pos < IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE)
- sa->replay_window = ((sa->replay_window) << pos) | 1;
+ /* the number of packets we saw in this section of the window */
+ clib_bitmap_t *window = sa->replay_window_huge;
+ u32 window_lower_bound = (sa->seq + 1) & (window_size - 1);
+ u32 window_next_lower_bound =
+ (window_lower_bound + inc) & (window_size - 1);
+
+ uword i_block, i_word_start, i_word_end, full_words;
+ uword n_blocks = window_size >> log2_uword_bits;
+ uword mask;
+
+ i_block = window_lower_bound >> log2_uword_bits;
+
+ i_word_start = window_lower_bound & (uword_bits - 1);
+ i_word_end = window_next_lower_bound & (uword_bits - 1);
+
+ /* We stay in the same word */
+ if (i_word_start + inc <= uword_bits)
+ {
+ mask = pow2_mask (inc) << i_word_start;
+ seen += count_set_bits (window[i_block] & mask);
+ window[i_block] &= ~mask;
+ }
else
- sa->replay_window = 1;
- sa->last_seq = seq;
+ {
+ full_words = (inc + i_word_start - uword_bits - i_word_end) >>
+ log2_uword_bits;
+
+ /* count set bits in the first word */
+ mask = (uword) ~0 << i_word_start;
+ seen += count_set_bits (window[i_block] & mask);
+ window[i_block] &= ~mask;
+ i_block = (i_block + 1) & (n_blocks - 1);
+
+ /* count set bits in the next full words */
+ /* even if the last word need to be fully counted, we treat it
+ * apart */
+ while (full_words >= 8)
+ {
+ if (full_words >= 16)
+ {
+ /* prefect the next 8 blocks (64 bytes) */
+ clib_prefetch_store (
+ &window[(i_block + 8) & (n_blocks - 1)]);
+ }
+
+ seen += count_set_bits (window[i_block]);
+ seen +=
+ count_set_bits (window[(i_block + 1) & (n_blocks - 1)]);
+ seen +=
+ count_set_bits (window[(i_block + 2) & (n_blocks - 1)]);
+ seen +=
+ count_set_bits (window[(i_block + 3) & (n_blocks - 1)]);
+ seen +=
+ count_set_bits (window[(i_block + 4) & (n_blocks - 1)]);
+ seen +=
+ count_set_bits (window[(i_block + 5) & (n_blocks - 1)]);
+ seen +=
+ count_set_bits (window[(i_block + 6) & (n_blocks - 1)]);
+ seen +=
+ count_set_bits (window[(i_block + 7) & (n_blocks - 1)]);
+ window[i_block] = 0;
+ window[(i_block + 1) & (n_blocks - 1)] = 0;
+ window[(i_block + 2) & (n_blocks - 1)] = 0;
+ window[(i_block + 3) & (n_blocks - 1)] = 0;
+ window[(i_block + 4) & (n_blocks - 1)] = 0;
+ window[(i_block + 5) & (n_blocks - 1)] = 0;
+ window[(i_block + 6) & (n_blocks - 1)] = 0;
+ window[(i_block + 7) & (n_blocks - 1)] = 0;
+
+ i_block = (i_block + 8) & (n_blocks - 1);
+ full_words -= 8;
+ }
+ while (full_words > 0)
+ {
+ // last word is treated after the loop
+ seen += count_set_bits (window[i_block]);
+ window[i_block] = 0;
+ i_block = (i_block + 1) & (n_blocks - 1);
+ full_words--;
+ }
+
+ /* the last word */
+ mask = pow2_mask (i_word_end);
+ seen += count_set_bits (window[i_block] & mask);
+ window[i_block] &= ~mask;
+ }
+
+ clib_bitmap_set_no_check (window,
+ (sa->seq + inc) & (window_size - 1), 1);
+ }
+ else
+ {
+ /*
+ * count how many holes there are in the portion
+ * of the window that we will right shift of the end
+ * as a result of this increments
+ */
+ u64 old = sa->replay_window & pow2_mask (inc);
+ /* the number of packets we saw in this section of the window */
+ seen = count_set_bits (old);
+ sa->replay_window =
+ ((sa->replay_window) >> inc) | (1ULL << (window_size - 1));
+ }
+
+ /*
+ * the number we missed is the size of the window section
+ * minus the number we saw.
+ */
+ n_lost = inc - seen;
+ }
+ else
+ {
+ /* holes in the replay window are lost packets */
+ n_lost = window_size - IPSEC_SA_ANTI_REPLAY_WINDOW_N_SEEN (sa);
+
+ /* any sequence numbers that now fall outside the window
+ * are forever lost */
+ n_lost += inc - window_size;
+
+ if (PREDICT_FALSE (ipsec_sa_is_set_ANTI_REPLAY_HUGE (sa)))
+ {
+ clib_bitmap_zero (sa->replay_window_huge);
+ clib_bitmap_set_no_check (sa->replay_window_huge,
+ (sa->seq + inc) & (window_size - 1), 1);
+ }
+ else
+ {
+ sa->replay_window = 1ULL << (window_size - 1);
+ }
+ }
+
+ return n_lost;
+}
+
+/*
+ * Anti replay window advance
+ * inputs need to be in host byte order.
+ * This function both advances the anti-replay window and the sequence number
+ * We always need to move on the SN but the window updates are only needed
+ * if AR is on.
+ * However, updating the window is trivial, so we do it anyway to save
+ * the branch cost.
+ */
+always_inline u64
+ipsec_sa_anti_replay_advance (ipsec_sa_t *sa, u32 thread_index, u32 seq,
+ u32 hi_seq, bool ar_huge)
+{
+ u64 n_lost = 0;
+ u32 window_size = IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE_KNOWN_WIN (sa, ar_huge);
+ u32 pos;
+
+ if (ipsec_sa_is_set_USE_ESN (sa))
+ {
+ int wrap = hi_seq - sa->seq_hi;
+
+ if (wrap == 0 && seq > sa->seq)
+ {
+ pos = seq - sa->seq;
+ n_lost = ipsec_sa_anti_replay_window_shift (sa, pos, ar_huge);
+ sa->seq = seq;
}
else if (wrap > 0)
{
- pos = ~seq + sa->last_seq + 1;
- if (pos < IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE)
- sa->replay_window = ((sa->replay_window) << pos) | 1;
- else
- sa->replay_window = 1;
- sa->last_seq = seq;
- sa->last_seq_hi = sa->seq_hi;
+ pos = seq + ~sa->seq + 1;
+ n_lost = ipsec_sa_anti_replay_window_shift (sa, pos, ar_huge);
+ sa->seq = seq;
+ sa->seq_hi = hi_seq;
}
else if (wrap < 0)
{
- pos = ~seq + sa->last_seq + 1;
- sa->replay_window |= (1ULL << pos);
+ pos = ~seq + sa->seq + 1;
+ if (ar_huge)
+ clib_bitmap_set_no_check (sa->replay_window_huge,
+ seq & (window_size - 1), 1);
+ else
+ sa->replay_window |= (1ULL << (window_size - 1 - pos));
}
else
{
- pos = sa->last_seq - seq;
- sa->replay_window |= (1ULL << pos);
+ pos = sa->seq - seq;
+ if (ar_huge)
+ clib_bitmap_set_no_check (sa->replay_window_huge,
+ seq & (window_size - 1), 1);
+ else
+ sa->replay_window |= (1ULL << (window_size - 1 - pos));
}
}
else
{
- if (seq > sa->last_seq)
+ if (seq > sa->seq)
{
- pos = seq - sa->last_seq;
- if (pos < IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE)
- sa->replay_window = ((sa->replay_window) << pos) | 1;
- else
- sa->replay_window = 1;
- sa->last_seq = seq;
+ pos = seq - sa->seq;
+ n_lost = ipsec_sa_anti_replay_window_shift (sa, pos, ar_huge);
+ sa->seq = seq;
}
else
{
- pos = sa->last_seq - seq;
- sa->replay_window |= (1ULL << pos);
+ pos = sa->seq - seq;
+ if (ar_huge)
+ clib_bitmap_set_no_check (sa->replay_window_huge,
+ seq & (window_size - 1), 1);
+ else
+ sa->replay_window |= (1ULL << (window_size - 1 - pos));
}
}
+
+ return n_lost;
+}
+
+
+/*
+ * Makes choice for thread_id should be assigned.
+ * if input ~0, gets random worker_id based on unix_time_now_nsec
+*/
+always_inline u16
+ipsec_sa_assign_thread (u16 thread_id)
+{
+ return ((thread_id) ? thread_id
+ : (unix_time_now_nsec () % vlib_num_workers ()) + 1);
+}
+
+always_inline ipsec_sa_t *
+ipsec_sa_get (u32 sa_index)
+{
+ return (pool_elt_at_index (ipsec_sa_pool, sa_index));
}
#endif /* __IPSEC_SPD_SA_H__ */