diff options
| -rw-r--r-- | src/selftest/counter.c | 13 | ||||
| -rw-r--r-- | src/wg_noise.c | 50 |
2 files changed, 33 insertions, 30 deletions
diff --git a/src/selftest/counter.c b/src/selftest/counter.c index 2c5d3bc..c715dec 100644 --- a/src/selftest/counter.c +++ b/src/selftest/counter.c @@ -10,18 +10,18 @@ rw_init(&kp.kp_nonce_lock, "counter"); \ } while (0) #define T(num, v, e) do { \ - if (noise_keypair_nonce_check(&kp, v) != e) { \ - printf("%s, test %d: FAIL\n", __func__, num); \ - return; \ + if (noise_keypair_nonce_check(&kp, v) != (e)) { \ + printf("nonce counter self-test %u: FAIL\n", num); \ + success = false; \ } \ } while (0) -#define T_PASSED printf("%s: pass\n", __func__) void noise_counter_selftest(void) { struct noise_keypair kp; - int i; + unsigned int i; + bool success = true; T_INIT; /* T(test number, nonce, expected_response) */ @@ -93,5 +93,6 @@ noise_counter_selftest(void) T(48, 0, 0); T(49, COUNTER_WINDOW_SIZE + 1, 0); - T_PASSED; + if (success) + printf("nonce counter self-test: pass\n"); } diff --git a/src/wg_noise.c b/src/wg_noise.c index 5e98fbe..f2c48dd 100644 --- a/src/wg_noise.c +++ b/src/wg_noise.c @@ -26,9 +26,15 @@ /* Constants for the counter */ #define COUNTER_BITS_TOTAL 8192 -#define COUNTER_BITS (sizeof(unsigned long) * 8) -#define COUNTER_NUM (COUNTER_BITS_TOTAL / COUNTER_BITS) -#define COUNTER_WINDOW_SIZE (COUNTER_BITS_TOTAL - COUNTER_BITS) +#ifdef __LP64__ +#define COUNTER_ORDER 6 +#define COUNTER_BITS 64 +#else +#define COUNTER_ORDER 5 +#define COUNTER_BITS 32 +#endif +#define COUNTER_REDUNDANT_BITS COUNTER_BITS +#define COUNTER_WINDOW_SIZE (COUNTER_BITS_TOTAL - COUNTER_REDUNDANT_BITS) /* Constants for the keypair */ #define REKEY_AFTER_MESSAGES (1ull << 60) @@ -68,7 +74,7 @@ struct noise_keypair { struct rwlock kp_nonce_lock; uint64_t kp_nonce_send; uint64_t kp_nonce_recv; - unsigned long kp_backtrack[COUNTER_NUM]; + unsigned long kp_backtrack[COUNTER_BITS_TOTAL / COUNTER_BITS]; struct epoch_context kp_smr; }; @@ -799,31 +805,29 @@ noise_keypair_nonce_next(struct noise_keypair *kp, uint64_t *send) int noise_keypair_nonce_check(struct noise_keypair *kp, uint64_t recv) { - uint64_t i, top, index_recv, index_ctr; - unsigned long bit; + unsigned long index, index_current, top, i, bit; int ret = EEXIST; rw_wlock(&kp->kp_nonce_lock); - /* Check that the recv counter is valid */ - if (kp->kp_nonce_recv >= REJECT_AFTER_MESSAGES || - recv >= REJECT_AFTER_MESSAGES) + if (__predict_false(kp->kp_nonce_recv >= REJECT_AFTER_MESSAGES + 1 || + recv >= REJECT_AFTER_MESSAGES)) goto error; - /* If the packet is out of the window, invalid */ - if (recv + COUNTER_WINDOW_SIZE < kp->kp_nonce_recv) + ++recv; + + if (__predict_false(recv + COUNTER_WINDOW_SIZE < kp->kp_nonce_recv)) goto error; - /* If the new counter is ahead of the current counter, we'll need to - * zero out the bitmap that has previously been used */ - index_recv = recv / COUNTER_BITS; - index_ctr = kp->kp_nonce_recv / COUNTER_BITS; + index = recv >> COUNTER_ORDER; - if (recv > kp->kp_nonce_recv) { - top = MIN(index_recv - index_ctr, COUNTER_NUM); + if (__predict_true(recv > kp->kp_nonce_recv)) { + index_current = kp->kp_nonce_recv >> COUNTER_ORDER; + top = MIN(index - index_current, COUNTER_BITS_TOTAL / COUNTER_BITS); for (i = 1; i <= top; i++) kp->kp_backtrack[ - (i + index_ctr) & (COUNTER_NUM - 1)] = 0; + (i + index_current) & + ((COUNTER_BITS_TOTAL / COUNTER_BITS) - 1)] = 0; #ifdef __LP64__ ck_pr_store_64(&kp->kp_nonce_recv, recv); #else @@ -831,14 +835,12 @@ noise_keypair_nonce_check(struct noise_keypair *kp, uint64_t recv) #endif } - index_recv %= COUNTER_NUM; - bit = 1ul << (recv % COUNTER_BITS); - - if (kp->kp_backtrack[index_recv] & bit) + index &= (COUNTER_BITS_TOTAL / COUNTER_BITS) - 1; + bit = 1ul << (recv & (COUNTER_BITS - 1)); + if (kp->kp_backtrack[index] & bit) goto error; - kp->kp_backtrack[index_recv] |= bit; - + kp->kp_backtrack[index] |= bit; ret = 0; error: rw_wunlock(&kp->kp_nonce_lock); |