commit 77d560af64226eaa0fde157d7a6607791975a7a9 Author: David Goulet dgoulet@torproject.org Date: Thu Mar 7 12:30:13 2019 -0500
prop289: Keep the digest bytes, not the object
The digest object is as large as the entire internal digest object's state, which is often much larger than the actual set of bytes you're transmitting.
This commit makes it that we keep the digest itself which is 20 bytes.
Part of #26288
Signed-off-by: David Goulet dgoulet@torproject.org --- src/core/crypto/relay_crypto.c | 17 ++++++----------- src/core/or/relay_crypto_st.h | 2 +- src/core/or/sendme.c | 29 +++++++++++------------------ src/core/or/sendme.h | 2 +- src/test/test_relaycell.c | 1 - src/test/test_sendme.c | 16 +++++++--------- 6 files changed, 26 insertions(+), 41 deletions(-)
diff --git a/src/core/crypto/relay_crypto.c b/src/core/crypto/relay_crypto.c index d4116d47a..94e906065 100644 --- a/src/core/crypto/relay_crypto.c +++ b/src/core/crypto/relay_crypto.c @@ -143,12 +143,9 @@ relay_decrypt_cell(circuit_t *circ, cell_t *cell, *recognized = 1; *layer_hint = thishop; /* Keep current digest of this cell for the possible SENDME. */ - if (thishop->crypto.sendme_digest) { - crypto_digest_free(thishop->crypto.sendme_digest); - } - thishop->crypto.sendme_digest = - crypto_digest_dup(thishop->crypto.b_digest); - + crypto_digest_get_digest(thishop->crypto.b_digest, + (char *) thishop->crypto.sendme_digest, + sizeof(thishop->crypto.sendme_digest)); return 0; } } @@ -220,10 +217,9 @@ relay_encrypt_cell_inbound(cell_t *cell, { relay_set_digest(or_circ->crypto.b_digest, cell); /* Keep a record of this cell, we might use it for validating the SENDME. */ - if (or_circ->crypto.sendme_digest) { - crypto_digest_free(or_circ->crypto.sendme_digest); - } - or_circ->crypto.sendme_digest = crypto_digest_dup(or_circ->crypto.b_digest); + crypto_digest_get_digest(or_circ->crypto.b_digest, + (char *) or_circ->crypto.sendme_digest, + sizeof(or_circ->crypto.sendme_digest)); /* encrypt one layer */ relay_crypt_one_payload(or_circ->crypto.b_crypto, cell->payload); } @@ -241,7 +237,6 @@ relay_crypto_clear(relay_crypto_t *crypto) crypto_cipher_free(crypto->b_crypto); crypto_digest_free(crypto->f_digest); crypto_digest_free(crypto->b_digest); - crypto_digest_free(crypto->sendme_digest); }
/** Initialize <b>crypto</b> from the key material in key_data. diff --git a/src/core/or/relay_crypto_st.h b/src/core/or/relay_crypto_st.h index dbdf1599d..1f243ccdc 100644 --- a/src/core/or/relay_crypto_st.h +++ b/src/core/or/relay_crypto_st.h @@ -26,7 +26,7 @@ struct relay_crypto_t { struct crypto_digest_t *b_digest;
/** Digest used for the next SENDME cell if any. */ - struct crypto_digest_t *sendme_digest; + uint8_t sendme_digest[DIGEST_LEN]; }; #undef crypto_cipher_t
diff --git a/src/core/or/sendme.c b/src/core/or/sendme.c index 0a7b1cbc0..3dcd9df08 100644 --- a/src/core/or/sendme.c +++ b/src/core/or/sendme.c @@ -215,7 +215,7 @@ sendme_is_valid(const circuit_t *circ, const uint8_t *cell_payload, * Return the size in bytes of the encoded cell in payload. A negative value * is returned on encoding failure. */ STATIC ssize_t -build_cell_payload_v1(crypto_digest_t *cell_digest, uint8_t *payload) +build_cell_payload_v1(const uint8_t *cell_digest, uint8_t *payload) { ssize_t len = -1; sendme_cell_t *cell = NULL; @@ -231,9 +231,8 @@ build_cell_payload_v1(crypto_digest_t *cell_digest, uint8_t *payload) sendme_cell_set_data_len(cell, TRUNNEL_SENDME_V1_DIGEST_LEN);
/* Copy the digest into the data payload. */ - crypto_digest_get_digest(cell_digest, - (char *) sendme_cell_getarray_data_v1_digest(cell), - sendme_cell_get_data_len(cell)); + memcpy(sendme_cell_getarray_data_v1_digest(cell), cell_digest, + sendme_cell_get_data_len(cell));
/* Finally, encode the cell into the payload. */ len = sendme_cell_encode(payload, RELAY_PAYLOAD_SIZE, cell); @@ -249,7 +248,7 @@ build_cell_payload_v1(crypto_digest_t *cell_digest, uint8_t *payload) * because we failed to send the cell on it. */ static int send_circuit_level_sendme(circuit_t *circ, crypt_path_t *layer_hint, - crypto_digest_t *cell_digest) + const uint8_t *cell_digest) { uint8_t emit_version; uint8_t payload[RELAY_PAYLOAD_SIZE]; @@ -340,7 +339,7 @@ sendme_connection_edge_consider_sending(edge_connection_t *conn) void sendme_circuit_consider_sending(circuit_t *circ, crypt_path_t *layer_hint) { - crypto_digest_t *digest; + const uint8_t *digest;
while ((layer_hint ? layer_hint->deliver_window : circ->deliver_window) <= CIRCWINDOW_START - CIRCWINDOW_INCREMENT) { @@ -539,7 +538,7 @@ sendme_note_stream_data_packaged(edge_connection_t *conn) void sendme_note_cell_digest(circuit_t *circ) { - uint8_t *digest; + const uint8_t *digest;
tor_assert(circ);
@@ -555,16 +554,10 @@ sendme_note_cell_digest(circuit_t *circ) return; }
- /* Only note the digest if we actually have the digest of the previous cell - * recorded. It should never happen in theory as we always record the last - * digest for the v1 SENDME. */ - if (TO_OR_CIRCUIT(circ)->crypto.sendme_digest) { - digest = tor_malloc_zero(TRUNNEL_SENDME_V1_DIGEST_LEN); - crypto_digest_get_digest(TO_OR_CIRCUIT(circ)->crypto.sendme_digest, - (char *) digest, TRUNNEL_SENDME_V1_DIGEST_LEN); - if (circ->sendme_last_digests == NULL) { - circ->sendme_last_digests = smartlist_new(); - } - smartlist_add(circ->sendme_last_digests, digest); + /* Add the digest to the last seen list in the circuit. */ + digest = TO_OR_CIRCUIT(circ)->crypto.sendme_digest; + if (circ->sendme_last_digests == NULL) { + circ->sendme_last_digests = smartlist_new(); } + smartlist_add(circ->sendme_last_digests, tor_memdup(digest, DIGEST_LEN)); } diff --git a/src/core/or/sendme.h b/src/core/or/sendme.h index 2154a29f4..71df9b6f0 100644 --- a/src/core/or/sendme.h +++ b/src/core/or/sendme.h @@ -50,7 +50,7 @@ STATIC int get_accept_min_version(void);
STATIC bool cell_version_is_valid(uint8_t cell_version);
-STATIC ssize_t build_cell_payload_v1(crypto_digest_t *cell_digest, +STATIC ssize_t build_cell_payload_v1(const uint8_t *cell_digest, uint8_t *payload); STATIC bool sendme_is_valid(const circuit_t *circ, const uint8_t *cell_payload, diff --git a/src/test/test_relaycell.c b/src/test/test_relaycell.c index c4ed215c7..062358351 100644 --- a/src/test/test_relaycell.c +++ b/src/test/test_relaycell.c @@ -705,7 +705,6 @@ test_circbw_relay(void *arg) circ = helper_create_origin_circuit(CIRCUIT_PURPOSE_C_GENERAL, 0); circ->cpath->state = CPATH_STATE_AWAITING_KEYS; circ->cpath->deliver_window = CIRCWINDOW_START; - circ->cpath->crypto.sendme_digest = crypto_digest_new();
entryconn1 = fake_entry_conn(circ, 1); edgeconn = ENTRY_TO_EDGE_CONN(entryconn1); diff --git a/src/test/test_sendme.c b/src/test/test_sendme.c index 92f478df0..d6410a748 100644 --- a/src/test/test_sendme.c +++ b/src/test/test_sendme.c @@ -16,6 +16,8 @@ #include "feature/nodelist/networkstatus.h" #include "feature/nodelist/networkstatus_st.h"
+#include "lib/crypt_ops/crypto_digest.h" + #include "test/test.h" #include "test/log_test_helpers.h"
@@ -64,7 +66,6 @@ test_v1_note_digest(void *arg) circuit_free_(circ); /* Points it to the OR circuit now. */ circ = TO_CIRCUIT(or_circ); - or_circ->crypto.sendme_digest = crypto_digest_new();
/* The package window has to be a multiple of CIRCWINDOW_INCREMENT minus 1 * in order to catched the CIRCWINDOW_INCREMENT-nth cell. Try something that @@ -144,7 +145,7 @@ test_v1_consensus_params(void *arg) static void test_v1_build_cell(void *arg) { - uint8_t payload[RELAY_PAYLOAD_SIZE]; + uint8_t payload[RELAY_PAYLOAD_SIZE], digest[DIGEST_LEN]; ssize_t ret; crypto_digest_t *cell_digest = NULL; or_circuit_t *or_circ = NULL; @@ -156,11 +157,12 @@ test_v1_build_cell(void *arg) circ = TO_CIRCUIT(or_circ);
cell_digest = crypto_digest_new(); - crypto_digest_add_bytes(cell_digest, "AAAAAAAAAAAAAAAAAAAA", 20); tt_assert(cell_digest); + crypto_digest_add_bytes(cell_digest, "AAAAAAAAAAAAAAAAAAAA", 20); + crypto_digest_get_digest(cell_digest, (char *) digest, sizeof(digest));
/* SENDME v1 payload is 3 bytes + 20 bytes digest. See spec. */ - ret = build_cell_payload_v1(cell_digest, payload); + ret = build_cell_payload_v1(digest, payload); tt_int_op(ret, OP_EQ, 23);
/* Validation. */ @@ -183,7 +185,6 @@ test_v1_build_cell(void *arg) teardown_capture_of_logs();
/* Note the wrong digest in the circuit, cell should fail validation. */ - or_circ->crypto.sendme_digest = crypto_digest_new(); circ->package_window = CIRCWINDOW_INCREMENT + 1; sendme_note_cell_digest(circ); tt_int_op(smartlist_len(circ->sendme_last_digests), OP_EQ, 1); @@ -194,11 +195,8 @@ test_v1_build_cell(void *arg) expect_log_msg_containing("SENDME v1 cell digest do not match."); teardown_capture_of_logs();
- /* Cleanup */ - crypto_digest_free(or_circ->crypto.sendme_digest); - /* Record the cell digest into the circuit, cell should validate. */ - or_circ->crypto.sendme_digest = crypto_digest_dup(cell_digest); + memcpy(or_circ->crypto.sendme_digest, digest, sizeof(digest)); circ->package_window = CIRCWINDOW_INCREMENT + 1; sendme_note_cell_digest(circ); tt_int_op(smartlist_len(circ->sendme_last_digests), OP_EQ, 1);