diff options
Diffstat (limited to 'vnet/vnet/ipsec/esp.h')
-rw-r--r-- | vnet/vnet/ipsec/esp.h | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/vnet/vnet/ipsec/esp.h b/vnet/vnet/ipsec/esp.h index b9feacbb322..50cac806d14 100644 --- a/vnet/vnet/ipsec/esp.h +++ b/vnet/vnet/ipsec/esp.h @@ -12,6 +12,8 @@ * See the License for the specific language governing permissions and * limitations under the License. */ +#ifndef __ESP_H__ +#define __ESP_H__ #include <openssl/hmac.h> #include <openssl/rand.h> @@ -77,6 +79,154 @@ typedef struct esp_main_t esp_main; +#define ESP_WINDOW_SIZE (64) +#define ESP_SEQ_MAX (4294967295UL) + + +always_inline int +esp_replay_check (ipsec_sa_t * sa, u32 seq) +{ + u32 diff; + + if (PREDICT_TRUE (seq > sa->last_seq)) + return 0; + + diff = sa->last_seq - seq; + + if (ESP_WINDOW_SIZE > diff) + return (sa->replay_window & (1ULL << diff)) ? 1 : 0; + else + return 1; + + return 0; +} + +always_inline int +esp_replay_check_esn (ipsec_sa_t * sa, u32 seq) +{ + u32 tl = sa->last_seq; + u32 th = sa->last_seq_hi; + u32 diff = tl - seq; + + if (PREDICT_TRUE (tl >= (ESP_WINDOW_SIZE - 1))) + { + if (seq >= (tl - ESP_WINDOW_SIZE + 1)) + { + sa->seq_hi = th; + if (seq <= tl) + return (sa->replay_window & (1ULL << diff)) ? 1 : 0; + else + return 0; + } + else + { + sa->seq_hi = th + 1; + return 0; + } + } + else + { + if (seq >= (tl - ESP_WINDOW_SIZE + 1)) + { + sa->seq_hi = th - 1; + return (sa->replay_window & (1ULL << diff)) ? 1 : 0; + } + else + { + sa->seq_hi = th; + if (seq <= tl) + return (sa->replay_window & (1ULL << diff)) ? 1 : 0; + else + return 0; + } + } + + return 0; +} + +/* TODO seq increment should be atomic to be accessed by multiple workers */ +always_inline void +esp_replay_advance (ipsec_sa_t * sa, u32 seq) +{ + u32 pos; + + if (seq > sa->last_seq) + { + pos = seq - sa->last_seq; + if (pos < ESP_WINDOW_SIZE) + sa->replay_window = ((sa->replay_window) << pos) | 1; + else + sa->replay_window = 1; + sa->last_seq = seq; + } + else + { + pos = sa->last_seq - seq; + sa->replay_window |= (1ULL << pos); + } +} + +always_inline void +esp_replay_advance_esn (ipsec_sa_t * sa, u32 seq) +{ + int wrap = sa->seq_hi - sa->last_seq_hi; + u32 pos; + + if (wrap == 0 && seq > sa->last_seq) + { + pos = seq - sa->last_seq; + if (pos < ESP_WINDOW_SIZE) + sa->replay_window = ((sa->replay_window) << pos) | 1; + else + sa->replay_window = 1; + sa->last_seq = seq; + } + else if (wrap > 0) + { + pos = ~seq + sa->last_seq + 1; + if (pos < ESP_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; + } + else if (wrap < 0) + { + pos = ~seq + sa->last_seq + 1; + sa->replay_window |= (1ULL << pos); + } + else + { + pos = sa->last_seq - seq; + sa->replay_window |= (1ULL << pos); + } +} + +always_inline int +esp_seq_advance (ipsec_sa_t * sa) +{ + if (PREDICT_TRUE (sa->use_esn)) + { + if (PREDICT_FALSE (sa->seq == ESP_SEQ_MAX)) + { + if (PREDICT_FALSE + (sa->use_anti_replay && sa->seq_hi == ESP_SEQ_MAX)) + return 1; + sa->seq_hi++; + } + sa->seq++; + } + else + { + if (PREDICT_FALSE (sa->use_anti_replay && sa->seq == ESP_SEQ_MAX)) + return 1; + sa->seq++; + } + + return 0; +} + always_inline void esp_init () { @@ -159,6 +309,7 @@ hmac_calc (ipsec_integ_alg_t alg, return em->esp_integ_algs[alg].trunc_size; } +#endif /* __ESP_H__ */ /* * fd.io coding-style-patch-verification: ON |