diff options
Diffstat (limited to 'src/or/rendservice.c')
| -rw-r--r-- | src/or/rendservice.c | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/src/or/rendservice.c b/src/or/rendservice.c index a935241162..f7ff71e4ec 100644 --- a/src/or/rendservice.c +++ b/src/or/rendservice.c @@ -958,6 +958,29 @@ rend_service_introduce(origin_circuit_t *circuit, const uint8_t *request, "PK-encrypted portion of INTRODUCE2 cell was truncated."); return -1; } + + if (!service->accepted_intros) + service->accepted_intros = digestmap_new(); + + { + char pkpart_digest[DIGEST_LEN]; + /* Check for replay of PK-encrypted portion. It is slightly naughty to + use the same digestmap to check for this and for g^x replays, but + collisions are tremendously unlikely. + */ + crypto_digest(pkpart_digest, (char*)request+DIGEST_LEN, keylen); + access_time = digestmap_get(service->accepted_intros, pkpart_digest); + if (access_time != NULL) { + log_warn(LD_REND, "Possible replay detected! We received an " + "INTRODUCE2 cell with same PK-encrypted part %d seconds ago. " + "Dropping cell.", (int)(now-*access_time)); + return -1; + } + access_time = tor_malloc(sizeof(time_t)); + *access_time = now; + digestmap_set(service->accepted_intros, pkpart_digest, access_time); + } + /* Next N bytes is encrypted with service key */ note_crypto_pk_op(REND_SERVER); r = crypto_pk_private_hybrid_decrypt( @@ -1100,9 +1123,6 @@ rend_service_introduce(origin_circuit_t *circuit, const uint8_t *request, /* Check whether there is a past request with the same Diffie-Hellman, * part 1. */ - if (!service->accepted_intros) - service->accepted_intros = digestmap_new(); - access_time = digestmap_get(service->accepted_intros, diffie_hellman_hash); if (access_time != NULL) { log_warn(LD_REND, "Possible replay detected! We received an " |