sarah
/
tor
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Merge remote-tracking branch 'public/split_relay_crypto'

This commit is contained in:
Nick Mathewson 2018-04-05 12:12:18 -04:00
parent 2933f73b31 a9fa483004
commit c6d7e0becf
15 changed files with 596 additions and 304 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

77
src/or/circuitbuild.c
View File

@ -56,6 +56,7 @@
#include "onion_fast.h"
#include "policies.h"
#include "relay.h"
#include "relay_crypto.h"
#include "rendcommon.h"
#include "rephist.h"
#include "router.h"
@ -1336,69 +1337,10 @@ circuit_init_cpath_crypto(crypt_path_t *cpath,
const char *key_data, size_t key_data_len,
int reverse, int is_hs_v3)
{
crypto_digest_t *tmp_digest;
crypto_cipher_t *tmp_crypto;
size_t digest_len = 0;
size_t cipher_key_len = 0;
tor_assert(cpath);
tor_assert(key_data);
tor_assert(!(cpath->f_crypto || cpath->b_crypto ||
cpath->f_digest || cpath->b_digest));
/* Basic key size validation */
if (is_hs_v3 && BUG(key_data_len != HS_NTOR_KEY_EXPANSION_KDF_OUT_LEN)) {
return -1;
} else if (!is_hs_v3 && BUG(key_data_len != CPATH_KEY_MATERIAL_LEN)) {
return -1;
}
/* If we are using this cpath for next gen onion services use SHA3-256,
otherwise use good ol' SHA1 */
if (is_hs_v3) {
digest_len = DIGEST256_LEN;
cipher_key_len = CIPHER256_KEY_LEN;
cpath->f_digest = crypto_digest256_new(DIGEST_SHA3_256);
cpath->b_digest = crypto_digest256_new(DIGEST_SHA3_256);
} else {
digest_len = DIGEST_LEN;
cipher_key_len = CIPHER_KEY_LEN;
cpath->f_digest = crypto_digest_new();
cpath->b_digest = crypto_digest_new();
}
tor_assert(digest_len != 0);
tor_assert(cipher_key_len != 0);
const int cipher_key_bits = (int) cipher_key_len * 8;
crypto_digest_add_bytes(cpath->f_digest, key_data, digest_len);
crypto_digest_add_bytes(cpath->b_digest, key_data+digest_len, digest_len);
cpath->f_crypto = crypto_cipher_new_with_bits(key_data+(2*digest_len),
cipher_key_bits);
if (!cpath->f_crypto) {
log_warn(LD_BUG,"Forward cipher initialization failed.");
return -1;
}
cpath->b_crypto = crypto_cipher_new_with_bits(
key_data+(2*digest_len)+cipher_key_len,
cipher_key_bits);
if (!cpath->b_crypto) {
log_warn(LD_BUG,"Backward cipher initialization failed.");
return -1;
}
if (reverse) {
tmp_digest = cpath->f_digest;
cpath->f_digest = cpath->b_digest;
cpath->b_digest = tmp_digest;
tmp_crypto = cpath->f_crypto;
cpath->f_crypto = cpath->b_crypto;
cpath->b_crypto = tmp_crypto;
}
return 0;
return relay_crypto_init(&cpath->crypto, key_data, key_data_len, reverse,
is_hs_v3);
}
/** A "created" cell <b>reply</b> came back to us on circuit <b>circ</b>.
@ -1521,7 +1463,6 @@ onionskin_answer(or_circuit_t *circ,
const uint8_t *rend_circ_nonce)
{
cell_t cell;
crypt_path_t *tmp_cpath;
tor_assert(keys_len == CPATH_KEY_MATERIAL_LEN);
@ -1532,25 +1473,15 @@ onionskin_answer(or_circuit_t *circ,
}
cell.circ_id = circ->p_circ_id;
tmp_cpath = tor_malloc_zero(sizeof(crypt_path_t));
tmp_cpath->magic = CRYPT_PATH_MAGIC;
circuit_set_state(TO_CIRCUIT(circ), CIRCUIT_STATE_OPEN);
log_debug(LD_CIRC,"init digest forward 0x%.8x, backward 0x%.8x.",
(unsigned int)get_uint32(keys),
(unsigned int)get_uint32(keys+20));
if (circuit_init_cpath_crypto(tmp_cpath, keys, keys_len, 0, 0)<0) {
if (relay_crypto_init(&circ->crypto, keys, keys_len, 0, 0)<0) {
log_warn(LD_BUG,"Circuit initialization failed");
tor_free(tmp_cpath);
return -1;
}
circ->n_digest = tmp_cpath->f_digest;
circ->n_crypto = tmp_cpath->f_crypto;
circ->p_digest = tmp_cpath->b_digest;
circ->p_crypto = tmp_cpath->b_crypto;
tmp_cpath->magic = 0;
tor_free(tmp_cpath);
memcpy(circ->rend_circ_nonce, rend_circ_nonce, DIGEST_LEN);

19
src/or/circuitlist.c
View File

@ -76,6 +76,7 @@
#include "onion_fast.h"
#include "policies.h"
#include "relay.h"
#include "relay_crypto.h"
#include "rendclient.h"
#include "rendcommon.h"
#include "rephist.h"
@ -1082,10 +1083,7 @@ circuit_free_(circuit_t *circ)
should_free = (ocirc->workqueue_entry == NULL);
crypto_cipher_free(ocirc->p_crypto);
crypto_digest_free(ocirc->p_digest);
crypto_cipher_free(ocirc->n_crypto);
crypto_digest_free(ocirc->n_digest);
relay_crypto_clear(&ocirc->crypto);
if (ocirc->rend_splice) {
or_circuit_t *other = ocirc->rend_splice;
@ -1225,10 +1223,7 @@ circuit_free_cpath_node(crypt_path_t *victim)
if (!victim)
return;
crypto_cipher_free(victim->f_crypto);
crypto_cipher_free(victim->b_crypto);
crypto_digest_free(victim->f_digest);
crypto_digest_free(victim->b_digest);
relay_crypto_clear(&victim->crypto);
onion_handshake_state_release(&victim->handshake_state);
crypto_dh_free(victim->rend_dh_handshake_state);
extend_info_free(victim->extend_info);
@ -2591,8 +2586,7 @@ assert_cpath_layer_ok(const crypt_path_t *cp)
switch (cp->state)
{
case CPATH_STATE_OPEN:
tor_assert(cp->f_crypto);
tor_assert(cp->b_crypto);
relay_crypto_assert_ok(&cp->crypto);
/* fall through */
case CPATH_STATE_CLOSED:
/*XXXX Assert that there's no handshake_state either. */
@ -2682,10 +2676,7 @@ assert_circuit_ok,(const circuit_t *c))
c->state == CIRCUIT_STATE_GUARD_WAIT) {
tor_assert(!c->n_chan_create_cell);
if (or_circ) {
tor_assert(or_circ->n_crypto);
tor_assert(or_circ->p_crypto);
tor_assert(or_circ->n_digest);
tor_assert(or_circ->p_digest);
relay_crypto_assert_ok(&or_circ->crypto);
}
}
if (c->state == CIRCUIT_STATE_CHAN_WAIT && !c->marked_for_close) {

2
src/or/include.am
View File

@ -91,6 +91,7 @@ LIBTOR_A_SOURCES = \
src/or/policies.c \
src/or/reasons.c \
src/or/relay.c \
src/or/relay_crypto.c \
src/or/rendcache.c \
src/or/rendclient.c \
src/or/rendcommon.c \
@ -237,6 +238,7 @@ ORHEADERS = \
src/or/proto_socks.h \
src/or/reasons.h \
src/or/relay.h \
src/or/relay_crypto.h \
src/or/rendcache.h \
src/or/rendclient.h \
src/or/rendcommon.h \

34
src/or/or.h
View File

@ -2899,11 +2899,7 @@ typedef struct {
} u;
} onion_handshake_state_t;
/** Holds accounting information for a single step in the layered encryption
* performed by a circuit. Used only at the client edge of a circuit. */
typedef struct crypt_path_t {
uint32_t magic;
typedef struct relay_crypto_t {
/* crypto environments */
/** Encryption key and counter for cells heading towards the OR at this
* step. */
@ -2917,6 +2913,17 @@ typedef struct crypt_path_t {
/** Digest state for cells heading away from the OR at this step. */
crypto_digest_t *b_digest;
} relay_crypto_t;
/** Holds accounting information for a single step in the layered encryption
* performed by a circuit. Used only at the client edge of a circuit. */
typedef struct crypt_path_t {
uint32_t magic;
/** Cryptographic state used for encrypting and authenticating relay
* cells to and from this hop. */
relay_crypto_t crypto;
/** Current state of the handshake as performed with the OR at this
* step. */
onion_handshake_state_t handshake_state;
@ -3465,21 +3472,10 @@ typedef struct or_circuit_t {
/** Linked list of Exit streams associated with this circuit that are
* still being resolved. */
edge_connection_t *resolving_streams;
/** The cipher used by intermediate hops for cells heading toward the
* OP. */
crypto_cipher_t *p_crypto;
/** The cipher used by intermediate hops for cells heading away from
* the OP. */
crypto_cipher_t *n_crypto;
/** The integrity-checking digest used by intermediate hops, for
* cells packaged here and heading towards the OP.
*/
crypto_digest_t *p_digest;
/** The integrity-checking digest used by intermediate hops, for
* cells packaged at the OP and arriving here.
*/
crypto_digest_t *n_digest;
/** Cryptographic state used for encrypting and authenticating relay
* cells to and from this hop. */
relay_crypto_t crypto;
/** Points to spliced circuit if purpose is REND_ESTABLISHED, and circuit
* is not marked for close. */

179
src/or/relay.c
View File

@ -70,6 +70,7 @@
#include "policies.h"
#include "reasons.h"
#include "relay.h"
#include "relay_crypto.h"
#include "rendcache.h"
#include "rendcommon.h"
#include "router.h"
@ -122,79 +123,6 @@ uint64_t stats_n_relay_cells_delivered = 0;
/** Used to tell which stream to read from first on a circuit. */
static tor_weak_rng_t stream_choice_rng = TOR_WEAK_RNG_INIT;
/** Update digest from the payload of cell. Assign integrity part to
* cell.
*/
static void
relay_set_digest(crypto_digest_t *digest, cell_t *cell)
{
char integrity[4];
relay_header_t rh;
crypto_digest_add_bytes(digest, (char*)cell->payload, CELL_PAYLOAD_SIZE);
crypto_digest_get_digest(digest, integrity, 4);
// log_fn(LOG_DEBUG,"Putting digest of %u %u %u %u into relay cell.",
// integrity[0], integrity[1], integrity[2], integrity[3]);
relay_header_unpack(&rh, cell->payload);
memcpy(rh.integrity, integrity, 4);
relay_header_pack(cell->payload, &rh);
}
/** Does the digest for this circuit indicate that this cell is for us?
*
* Update digest from the payload of cell (with the integrity part set
* to 0). If the integrity part is valid, return 1, else restore digest
* and cell to their original state and return 0.
*/
static int
relay_digest_matches(crypto_digest_t *digest, cell_t *cell)
{
uint32_t received_integrity, calculated_integrity;
relay_header_t rh;
crypto_digest_checkpoint_t backup_digest;
crypto_digest_checkpoint(&backup_digest, digest);
relay_header_unpack(&rh, cell->payload);
memcpy(&received_integrity, rh.integrity, 4);
memset(rh.integrity, 0, 4);
relay_header_pack(cell->payload, &rh);
// log_fn(LOG_DEBUG,"Reading digest of %u %u %u %u from relay cell.",
// received_integrity[0], received_integrity[1],
// received_integrity[2], received_integrity[3]);
crypto_digest_add_bytes(digest, (char*) cell->payload, CELL_PAYLOAD_SIZE);
crypto_digest_get_digest(digest, (char*) &calculated_integrity, 4);
int rv = 1;
if (calculated_integrity != received_integrity) {
// log_fn(LOG_INFO,"Recognized=0 but bad digest. Not recognizing.");
// (%d vs %d).", received_integrity, calculated_integrity);
/* restore digest to its old form */
crypto_digest_restore(digest, &backup_digest);
/* restore the relay header */
memcpy(rh.integrity, &received_integrity, 4);
relay_header_pack(cell->payload, &rh);
rv = 0;
}
memwipe(&backup_digest, 0, sizeof(backup_digest));
return rv;
}
/** Apply <b>cipher</b> to CELL_PAYLOAD_SIZE bytes of <b>in</b>
* (in place).
*
* Note that we use the same operation for encrypting and for decrypting.
*/
static void
relay_crypt_one_payload(crypto_cipher_t *cipher, uint8_t *in)
{
crypto_cipher_crypt_inplace(cipher, (char*) in, CELL_PAYLOAD_SIZE);
}
/**
* Update channel usage state based on the type of relay cell and
* circuit properties.
@ -299,7 +227,8 @@ circuit_receive_relay_cell(cell_t *cell, circuit_t *circ,
if (circ->marked_for_close)
return 0;
if (relay_crypt(circ, cell, cell_direction, &layer_hint, &recognized) < 0) {
if (relay_decrypt_cell(circ, cell, cell_direction, &layer_hint, &recognized)
< 0) {
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
"relay crypt failed. Dropping connection.");
return -END_CIRC_REASON_INTERNAL;
@ -404,87 +333,6 @@ circuit_receive_relay_cell(cell_t *cell, circuit_t *circ,
return 0;
}
/** Do the appropriate en/decryptions for <b>cell</b> arriving on
* <b>circ</b> in direction <b>cell_direction</b>.
*
* If cell_direction == CELL_DIRECTION_IN:
* - If we're at the origin (we're the OP), for hops 1..N,
* decrypt cell. If recognized, stop.
* - Else (we're not the OP), encrypt one hop. Cell is not recognized.
*
* If cell_direction == CELL_DIRECTION_OUT:
* - decrypt one hop. Check if recognized.
*
* If cell is recognized, set *recognized to 1, and set
* *layer_hint to the hop that recognized it.
*
* Return -1 to indicate that we should mark the circuit for close,
* else return 0.
*/
int
relay_crypt(circuit_t *circ, cell_t *cell, cell_direction_t cell_direction,
crypt_path_t **layer_hint, char *recognized)
{
relay_header_t rh;
tor_assert(circ);
tor_assert(cell);
tor_assert(recognized);
tor_assert(cell_direction == CELL_DIRECTION_IN ||
cell_direction == CELL_DIRECTION_OUT);
if (cell_direction == CELL_DIRECTION_IN) {
if (CIRCUIT_IS_ORIGIN(circ)) { /* We're at the beginning of the circuit.
* We'll want to do layered decrypts. */
crypt_path_t *thishop, *cpath = TO_ORIGIN_CIRCUIT(circ)->cpath;
thishop = cpath;
if (thishop->state != CPATH_STATE_OPEN) {
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
"Relay cell before first created cell? Closing.");
return -1;
}
do { /* Remember: cpath is in forward order, that is, first hop first. */
tor_assert(thishop);
/* decrypt one layer */
relay_crypt_one_payload(thishop->b_crypto, cell->payload);
relay_header_unpack(&rh, cell->payload);
if (rh.recognized == 0) {
/* it's possibly recognized. have to check digest to be sure. */
if (relay_digest_matches(thishop->b_digest, cell)) {
*recognized = 1;
*layer_hint = thishop;
return 0;
}
}
thishop = thishop->next;
} while (thishop != cpath && thishop->state == CPATH_STATE_OPEN);
log_fn(LOG_PROTOCOL_WARN, LD_OR,
"Incoming cell at client not recognized. Closing.");
return -1;
} else {
/* We're in the middle. Encrypt one layer. */
relay_crypt_one_payload(TO_OR_CIRCUIT(circ)->p_crypto, cell->payload);
}
} else /* cell_direction == CELL_DIRECTION_OUT */ {
/* We're in the middle. Decrypt one layer. */
relay_crypt_one_payload(TO_OR_CIRCUIT(circ)->n_crypto, cell->payload);
relay_header_unpack(&rh, cell->payload);
if (rh.recognized == 0) {
/* it's possibly recognized. have to check digest to be sure. */
if (relay_digest_matches(TO_OR_CIRCUIT(circ)->n_digest, cell)) {
*recognized = 1;
return 0;
}
}
}
return 0;
}
/** Package a relay cell from an edge:
* - Encrypt it to the right layer
* - Append it to the appropriate cell_queue on <b>circ</b>.
@ -503,7 +351,6 @@ circuit_package_relay_cell(cell_t *cell, circuit_t *circ,
}
if (cell_direction == CELL_DIRECTION_OUT) {
crypt_path_t *thishop; /* counter for repeated crypts */
chan = circ->n_chan;
if (!chan) {
log_warn(LD_BUG,"outgoing relay cell sent from %s:%d has n_chan==NULL."
@ -526,20 +373,8 @@ circuit_package_relay_cell(cell_t *cell, circuit_t *circ,
return 0; /* just drop it */
}
relay_set_digest(layer_hint->f_digest, cell);
thishop = layer_hint;
/* moving from farthest to nearest hop */
do {
tor_assert(thishop);
log_debug(LD_OR,"encrypting a layer of the relay cell.");
relay_crypt_one_payload(thishop->f_crypto, cell->payload);
thishop = thishop->prev;
} while (thishop != TO_ORIGIN_CIRCUIT(circ)->cpath->prev);
relay_encrypt_cell_outbound(cell, TO_ORIGIN_CIRCUIT(circ), layer_hint);
} else { /* incoming cell */
or_circuit_t *or_circ;
if (CIRCUIT_IS_ORIGIN(circ)) {
/* We should never package an _incoming_ cell from the circuit
* origin; that means we messed up somewhere. */
@ -547,11 +382,9 @@ circuit_package_relay_cell(cell_t *cell, circuit_t *circ,
assert_circuit_ok(circ);
return 0; /* just drop it */
}
or_circ = TO_OR_CIRCUIT(circ);
or_circuit_t *or_circ = TO_OR_CIRCUIT(circ);
relay_encrypt_cell_inbound(cell, or_circ);
chan = or_circ->p_chan;
relay_set_digest(or_circ->p_digest, cell);
/* encrypt one layer */
relay_crypt_one_payload(or_circ->p_crypto, cell->payload);
}
++stats_n_relay_cells_relayed;

3
src/or/relay.h
View File

@ -89,9 +89,6 @@ void circuit_clear_cell_queue(circuit_t *circ, channel_t *chan);
void stream_choice_seed_weak_rng(void);
int relay_crypt(circuit_t *circ, cell_t *cell, cell_direction_t cell_direction,
crypt_path_t **layer_hint, char *recognized);
circid_t packed_cell_get_circid(const packed_cell_t *cell, int wide_circ_ids);
#ifdef RELAY_PRIVATE

326
src/or/relay_crypto.c Normal file
View File

@ -0,0 +1,326 @@
/* Copyright (c) 2001 Matej Pfajfar.
* Copyright (c) 2001-2004, Roger Dingledine.
* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
* Copyright (c) 2007-2018, The Tor Project, Inc. */
/* See LICENSE for licensing information */
#include "or.h"
#include "config.h"
#include "hs_ntor.h" // for HS_NTOR_KEY_EXPANSION_KDF_OUT_LEN
#include "relay_crypto.h"
#include "relay.h"
/** Update digest from the payload of cell. Assign integrity part to
* cell.
*/
static void
relay_set_digest(crypto_digest_t *digest, cell_t *cell)
{
char integrity[4];
relay_header_t rh;
crypto_digest_add_bytes(digest, (char*)cell->payload, CELL_PAYLOAD_SIZE);
crypto_digest_get_digest(digest, integrity, 4);
// log_fn(LOG_DEBUG,"Putting digest of %u %u %u %u into relay cell.",
// integrity[0], integrity[1], integrity[2], integrity[3]);
relay_header_unpack(&rh, cell->payload);
memcpy(rh.integrity, integrity, 4);
relay_header_pack(cell->payload, &rh);
}
/** Does the digest for this circuit indicate that this cell is for us?
*
* Update digest from the payload of cell (with the integrity part set
* to 0). If the integrity part is valid, return 1, else restore digest
* and cell to their original state and return 0.
*/
static int
relay_digest_matches(crypto_digest_t *digest, cell_t *cell)
{
uint32_t received_integrity, calculated_integrity;
relay_header_t rh;
crypto_digest_checkpoint_t backup_digest;
crypto_digest_checkpoint(&backup_digest, digest);
relay_header_unpack(&rh, cell->payload);
memcpy(&received_integrity, rh.integrity, 4);
memset(rh.integrity, 0, 4);
relay_header_pack(cell->payload, &rh);
// log_fn(LOG_DEBUG,"Reading digest of %u %u %u %u from relay cell.",
// received_integrity[0], received_integrity[1],
// received_integrity[2], received_integrity[3]);
crypto_digest_add_bytes(digest, (char*) cell->payload, CELL_PAYLOAD_SIZE);
crypto_digest_get_digest(digest, (char*) &calculated_integrity, 4);
int rv = 1;
if (calculated_integrity != received_integrity) {
// log_fn(LOG_INFO,"Recognized=0 but bad digest. Not recognizing.");
// (%d vs %d).", received_integrity, calculated_integrity);
/* restore digest to its old form */
crypto_digest_restore(digest, &backup_digest);
/* restore the relay header */
memcpy(rh.integrity, &received_integrity, 4);
relay_header_pack(cell->payload, &rh);
rv = 0;
}
memwipe(&backup_digest, 0, sizeof(backup_digest));
return rv;
}
/** Apply <b>cipher</b> to CELL_PAYLOAD_SIZE bytes of <b>in</b>
* (in place).
*
* Note that we use the same operation for encrypting and for decrypting.
*/
static void
relay_crypt_one_payload(crypto_cipher_t *cipher, uint8_t *in)
{
crypto_cipher_crypt_inplace(cipher, (char*) in, CELL_PAYLOAD_SIZE);
}
/** Do the appropriate en/decryptions for <b>cell</b> arriving on
* <b>circ</b> in direction <b>cell_direction</b>.
*
* If cell_direction == CELL_DIRECTION_IN:
* - If we're at the origin (we're the OP), for hops 1..N,
* decrypt cell. If recognized, stop.
* - Else (we're not the OP), encrypt one hop. Cell is not recognized.
*
* If cell_direction == CELL_DIRECTION_OUT:
* - decrypt one hop. Check if recognized.
*
* If cell is recognized, set *recognized to 1, and set
* *layer_hint to the hop that recognized it.
*
* Return -1 to indicate that we should mark the circuit for close,
* else return 0.
*/
int
relay_decrypt_cell(circuit_t *circ, cell_t *cell,
cell_direction_t cell_direction,
crypt_path_t **layer_hint, char *recognized)
{
relay_header_t rh;
tor_assert(circ);
tor_assert(cell);
tor_assert(recognized);
tor_assert(cell_direction == CELL_DIRECTION_IN ||
cell_direction == CELL_DIRECTION_OUT);
if (cell_direction == CELL_DIRECTION_IN) {
if (CIRCUIT_IS_ORIGIN(circ)) { /* We're at the beginning of the circuit.
* We'll want to do layered decrypts. */
crypt_path_t *thishop, *cpath = TO_ORIGIN_CIRCUIT(circ)->cpath;
thishop = cpath;
if (thishop->state != CPATH_STATE_OPEN) {
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
"Relay cell before first created cell? Closing.");
return -1;
}
do { /* Remember: cpath is in forward order, that is, first hop first. */
tor_assert(thishop);
/* decrypt one layer */
relay_crypt_one_payload(thishop->crypto.b_crypto, cell->payload);
relay_header_unpack(&rh, cell->payload);
if (rh.recognized == 0) {
/* it's possibly recognized. have to check digest to be sure. */
if (relay_digest_matches(thishop->crypto.b_digest, cell)) {
*recognized = 1;
*layer_hint = thishop;
return 0;
}
}
thishop = thishop->next;
} while (thishop != cpath && thishop->state == CPATH_STATE_OPEN);
log_fn(LOG_PROTOCOL_WARN, LD_OR,
"Incoming cell at client not recognized. Closing.");
return -1;
} else {
relay_crypto_t *crypto = &TO_OR_CIRCUIT(circ)->crypto;
/* We're in the middle. Encrypt one layer. */
relay_crypt_one_payload(crypto->b_crypto, cell->payload);
}
} else /* cell_direction == CELL_DIRECTION_OUT */ {
/* We're in the middle. Decrypt one layer. */
relay_crypto_t *crypto = &TO_OR_CIRCUIT(circ)->crypto;
relay_crypt_one_payload(crypto->f_crypto, cell->payload);
relay_header_unpack(&rh, cell->payload);
if (rh.recognized == 0) {
/* it's possibly recognized. have to check digest to be sure. */
if (relay_digest_matches(crypto->f_digest, cell)) {
*recognized = 1;
return 0;
}
}
}
return 0;
}
/**
* Encrypt a cell <b>cell</b> that we are creating, and sending outbound on
* <b>circ</b> until the hop corresponding to <b>layer_hint</b>.
*
* The integrity field and recognized field of <b>cell</b>'s relay headers
* must be set to zero.
*/
void
relay_encrypt_cell_outbound(cell_t *cell,
origin_circuit_t *circ,
crypt_path_t *layer_hint)
{
crypt_path_t *thishop; /* counter for repeated crypts */
relay_set_digest(layer_hint->crypto.f_digest, cell);
thishop = layer_hint;
/* moving from farthest to nearest hop */
do {
tor_assert(thishop);
log_debug(LD_OR,"encrypting a layer of the relay cell.");
relay_crypt_one_payload(thishop->crypto.f_crypto, cell->payload);
thishop = thishop->prev;
} while (thishop != circ->cpath->prev);
}
/**
* Encrypt a cell <b>cell</b> that we are creating, and sending on
* <b>circuit</b> to the origin.
*
* The integrity field and recognized field of <b>cell</b>'s relay headers
* must be set to zero.
*/
void
relay_encrypt_cell_inbound(cell_t *cell,
or_circuit_t *or_circ)
{
relay_set_digest(or_circ->crypto.b_digest, cell);
/* encrypt one layer */
relay_crypt_one_payload(or_circ->crypto.b_crypto, cell->payload);
}
/**
* Release all storage held inside <b>crypto</b>, but do not free
* <b>crypto</b> itself: it lives inside another object.
*/
void
relay_crypto_clear(relay_crypto_t *crypto)
{
if (BUG(!crypto))
return;
crypto_cipher_free(crypto->f_crypto);
crypto_cipher_free(crypto->b_crypto);
crypto_digest_free(crypto->f_digest);
crypto_digest_free(crypto->b_digest);
}
/** Initialize <b>crypto</b> from the key material in key_data.
*
* If <b>is_hs_v3</b> is set, this cpath will be used for next gen hidden
* service circuits and <b>key_data</b> must be at least
* HS_NTOR_KEY_EXPANSION_KDF_OUT_LEN bytes in length.
*
* If <b>is_hs_v3</b> is not set, key_data must contain CPATH_KEY_MATERIAL_LEN
* bytes, which are used as follows:
* - 20 to initialize f_digest
* - 20 to initialize b_digest
* - 16 to key f_crypto
* - 16 to key b_crypto
*
* (If 'reverse' is true, then f_XX and b_XX are swapped.)
*
* Return 0 if init was successful, else -1 if it failed.
*/
int
relay_crypto_init(relay_crypto_t *crypto,
const char *key_data, size_t key_data_len,
int reverse, int is_hs_v3)
{
crypto_digest_t *tmp_digest;
crypto_cipher_t *tmp_crypto;
size_t digest_len = 0;
size_t cipher_key_len = 0;
tor_assert(crypto);
tor_assert(key_data);
tor_assert(!(crypto->f_crypto || crypto->b_crypto ||
crypto->f_digest || crypto->b_digest));
/* Basic key size validation */
if (is_hs_v3 && BUG(key_data_len != HS_NTOR_KEY_EXPANSION_KDF_OUT_LEN)) {
goto err;
} else if (!is_hs_v3 && BUG(key_data_len != CPATH_KEY_MATERIAL_LEN)) {
goto err;
}
/* If we are using this crypto for next gen onion services use SHA3-256,
otherwise use good ol' SHA1 */
if (is_hs_v3) {
digest_len = DIGEST256_LEN;
cipher_key_len = CIPHER256_KEY_LEN;
crypto->f_digest = crypto_digest256_new(DIGEST_SHA3_256);
crypto->b_digest = crypto_digest256_new(DIGEST_SHA3_256);
} else {
digest_len = DIGEST_LEN;
cipher_key_len = CIPHER_KEY_LEN;
crypto->f_digest = crypto_digest_new();
crypto->b_digest = crypto_digest_new();
}
tor_assert(digest_len != 0);
tor_assert(cipher_key_len != 0);
const int cipher_key_bits = (int) cipher_key_len * 8;
crypto_digest_add_bytes(crypto->f_digest, key_data, digest_len);
crypto_digest_add_bytes(crypto->b_digest, key_data+digest_len, digest_len);
crypto->f_crypto = crypto_cipher_new_with_bits(key_data+(2*digest_len),
cipher_key_bits);
if (!crypto->f_crypto) {
log_warn(LD_BUG,"Forward cipher initialization failed.");
goto err;
}
crypto->b_crypto = crypto_cipher_new_with_bits(
key_data+(2*digest_len)+cipher_key_len,
cipher_key_bits);
if (!crypto->b_crypto) {
log_warn(LD_BUG,"Backward cipher initialization failed.");
goto err;
}
if (reverse) {
tmp_digest = crypto->f_digest;
crypto->f_digest = crypto->b_digest;
crypto->b_digest = tmp_digest;
tmp_crypto = crypto->f_crypto;
crypto->f_crypto = crypto->b_crypto;
crypto->b_crypto = tmp_crypto;
}
return 0;
err:
relay_crypto_clear(crypto);
return -1;
}
/** Assert that <b>crypto</b> is valid and set. */
void
relay_crypto_assert_ok(const relay_crypto_t *crypto)
{
tor_assert(crypto->f_crypto);
tor_assert(crypto->b_crypto);
tor_assert(crypto->f_digest);
tor_assert(crypto->b_digest);
}

31
src/or/relay_crypto.h Normal file
View File

@ -0,0 +1,31 @@
/* Copyright (c) 2001 Matej Pfajfar.
* Copyright (c) 2001-2004, Roger Dingledine.
* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
* Copyright (c) 2007-2017, The Tor Project, Inc. */
/* See LICENSE for licensing information */
/**
* \file relay.h
* \brief Header file for relay.c.
**/
#ifndef TOR_RELAY_CRYPTO_H
#define TOR_RELAY_CRYPTO_H
int relay_crypto_init(relay_crypto_t *crypto,
const char *key_data, size_t key_data_len,
int reverse, int is_hs_v3);
int relay_decrypt_cell(circuit_t *circ, cell_t *cell,
cell_direction_t cell_direction,
crypt_path_t **layer_hint, char *recognized);
void relay_encrypt_cell_outbound(cell_t *cell, origin_circuit_t *or_circ,
crypt_path_t *layer_hint);
void relay_encrypt_cell_inbound(cell_t *cell, or_circuit_t *or_circ);
void relay_crypto_clear(relay_crypto_t *crypto);
void relay_crypto_assert_ok(const relay_crypto_t *crypto);
#endif /* !defined(TOR_RELAY_CRYPTO_H) */

18
src/test/bench.c
View File

@ -12,7 +12,7 @@
#include "or.h"
#include "onion_tap.h"
#include "relay.h"
#include "relay_crypto.h"
#include <openssl/opensslv.h>
#include <openssl/evp.h>
#include <openssl/ec.h>
@ -505,10 +505,10 @@ bench_cell_ops(void)
char key1[CIPHER_KEY_LEN], key2[CIPHER_KEY_LEN];
crypto_rand(key1, sizeof(key1));
crypto_rand(key2, sizeof(key2));
or_circ->p_crypto = crypto_cipher_new(key1);
or_circ->n_crypto = crypto_cipher_new(key2);
or_circ->p_digest = crypto_digest_new();
or_circ->n_digest = crypto_digest_new();
or_circ->crypto.f_crypto = crypto_cipher_new(key1);
or_circ->crypto.b_crypto = crypto_cipher_new(key2);
or_circ->crypto.f_digest = crypto_digest_new();
or_circ->crypto.b_digest = crypto_digest_new();
reset_perftime();
@ -518,7 +518,8 @@ bench_cell_ops(void)
for (i = 0; i < iters; ++i) {
char recognized = 0;
crypt_path_t *layer_hint = NULL;
relay_crypt(TO_CIRCUIT(or_circ), cell, d, &layer_hint, &recognized);
relay_decrypt_cell(TO_CIRCUIT(or_circ), cell, d,
&layer_hint, &recognized);
}
end = perftime();
printf("%sbound cells: %.2f ns per cell. (%.2f ns per byte of payload)\n",
@ -527,10 +528,7 @@ bench_cell_ops(void)
NANOCOUNT(start,end,iters*CELL_PAYLOAD_SIZE));
}
crypto_digest_free(or_circ->p_digest);
crypto_digest_free(or_circ->n_digest);
crypto_cipher_free(or_circ->p_crypto);
crypto_cipher_free(or_circ->n_crypto);
relay_crypto_clear(&or_circ->crypto);
tor_free(or_circ);
tor_free(cell);
}

1
src/test/include.am
View File

@ -151,6 +151,7 @@ src_test_test_SOURCES = \
src/test/test_pubsub.c \
src/test/test_relay.c \
src/test/test_relaycell.c \
src/test/test_relaycrypt.c \
src/test/test_rendcache.c \
src/test/test_replay.c \
src/test/test_router.c \

1
src/test/test.c
View File

@ -869,6 +869,7 @@ struct testgroup_t testgroups[] = {
{ "pt/", pt_tests },
{ "relay/" , relay_tests },
{ "relaycell/", relaycell_tests },
{ "relaycrypt/", relaycrypt_tests },
{ "rend_cache/", rend_cache_tests },
{ "replaycache/", replaycache_tests },
{ "router/", router_tests },

1
src/test/test.h
View File

@ -238,6 +238,7 @@ extern struct testcase_t pubsub_tests[];
extern struct testcase_t pt_tests[];
extern struct testcase_t relay_tests[];
extern struct testcase_t relaycell_tests[];
extern struct testcase_t relaycrypt_tests[];
extern struct testcase_t rend_cache_tests[];
extern struct testcase_t replaycache_tests[];
extern struct testcase_t router_tests[];

16
src/test/test_hs_client.c
View File

@ -213,12 +213,12 @@ test_e2e_rend_circuit_setup_legacy(void *arg)
tt_int_op(retval, OP_EQ, 1);
/* Check the digest algo */
tt_int_op(crypto_digest_get_algorithm(or_circ->cpath->f_digest),
tt_int_op(crypto_digest_get_algorithm(or_circ->cpath->crypto.f_digest),
OP_EQ, DIGEST_SHA1);
tt_int_op(crypto_digest_get_algorithm(or_circ->cpath->b_digest),
tt_int_op(crypto_digest_get_algorithm(or_circ->cpath->crypto.b_digest),
OP_EQ, DIGEST_SHA1);
tt_assert(or_circ->cpath->f_crypto);
tt_assert(or_circ->cpath->b_crypto);
tt_assert(or_circ->cpath->crypto.f_crypto);
tt_assert(or_circ->cpath->crypto.b_crypto);
/* Ensure that circ purpose was changed */
tt_int_op(or_circ->base_.purpose, OP_EQ, CIRCUIT_PURPOSE_C_REND_JOINED);
@ -283,12 +283,12 @@ test_e2e_rend_circuit_setup(void *arg)
tt_int_op(retval, OP_EQ, 1);
/* Check that the crypt path has prop224 algorithm parameters */
tt_int_op(crypto_digest_get_algorithm(or_circ->cpath->f_digest),
tt_int_op(crypto_digest_get_algorithm(or_circ->cpath->crypto.f_digest),
OP_EQ, DIGEST_SHA3_256);
tt_int_op(crypto_digest_get_algorithm(or_circ->cpath->b_digest),
tt_int_op(crypto_digest_get_algorithm(or_circ->cpath->crypto.b_digest),
OP_EQ, DIGEST_SHA3_256);
tt_assert(or_circ->cpath->f_crypto);
tt_assert(or_circ->cpath->b_crypto);
tt_assert(or_circ->cpath->crypto.f_crypto);
tt_assert(or_circ->cpath->crypto.b_crypto);
/* Ensure that circ purpose was changed */
tt_int_op(or_circ->base_.purpose, OP_EQ, CIRCUIT_PURPOSE_C_REND_JOINED);

8
src/test/test_hs_service.c
View File

@ -173,12 +173,12 @@ test_e2e_rend_circuit_setup(void *arg)
tt_int_op(retval, OP_EQ, 1);
/* Check the digest algo */
tt_int_op(crypto_digest_get_algorithm(or_circ->cpath->f_digest),
tt_int_op(crypto_digest_get_algorithm(or_circ->cpath->crypto.f_digest),
OP_EQ, DIGEST_SHA3_256);
tt_int_op(crypto_digest_get_algorithm(or_circ->cpath->b_digest),
tt_int_op(crypto_digest_get_algorithm(or_circ->cpath->crypto.b_digest),
OP_EQ, DIGEST_SHA3_256);
tt_assert(or_circ->cpath->f_crypto);
tt_assert(or_circ->cpath->b_crypto);
tt_assert(or_circ->cpath->crypto.f_crypto);
tt_assert(or_circ->cpath->crypto.b_crypto);
/* Ensure that circ purpose was changed */
tt_int_op(or_circ->base_.purpose, OP_EQ, CIRCUIT_PURPOSE_S_REND_JOINED);

184
src/test/test_relaycrypt.c Normal file
View File

@ -0,0 +1,184 @@
/* Copyright 2001-2004 Roger Dingledine.
* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
* Copyright (c) 2007-2018, The Tor Project, Inc. */
/* See LICENSE for licensing information */
#include "or.h"
#include "circuitbuild.h"
#define CIRCUITLIST_PRIVATE
#include "circuitlist.h"
#include "relay.h"
#include "relay_crypto.h"
#include "test.h"
static const char KEY_MATERIAL[3][CPATH_KEY_MATERIAL_LEN] = {
" 'My public key is in this signed x509 object', said Tom assertively.",
"'Let's chart the pedal phlanges in the tomb', said Tom cryptographically",
" 'Segmentation fault bugs don't _just happen_', said Tom seethingly.",
};
typedef struct testing_circuitset_t {
or_circuit_t *or_circ[3];
origin_circuit_t *origin_circ;
} testing_circuitset_t;
static int testing_circuitset_teardown(const struct testcase_t *testcase,
void *ptr);
static void *
testing_circuitset_setup(const struct testcase_t *testcase)
{
testing_circuitset_t *cs = tor_malloc_zero(sizeof(testing_circuitset_t));
int i;
for (i=0; i<3; ++i) {
cs->or_circ[i] = or_circuit_new(0, NULL);
tt_int_op(0, OP_EQ,
relay_crypto_init(&cs->or_circ[i]->crypto,
KEY_MATERIAL[i], sizeof(KEY_MATERIAL[i]),
0, 0));
}
cs->origin_circ = origin_circuit_new();
cs->origin_circ->base_.purpose = CIRCUIT_PURPOSE_C_GENERAL;
for (i=0; i<3; ++i) {
crypt_path_t *hop = tor_malloc_zero(sizeof(*hop));
relay_crypto_init(&hop->crypto, KEY_MATERIAL[i], sizeof(KEY_MATERIAL[i]),
0, 0);
hop->state = CPATH_STATE_OPEN;
onion_append_to_cpath(&cs->origin_circ->cpath, hop);
tt_ptr_op(hop, OP_EQ, cs->origin_circ->cpath->prev);
}
return cs;
done:
testing_circuitset_teardown(testcase, cs);
return NULL;
}
static int
testing_circuitset_teardown(const struct testcase_t *testcase, void *ptr)
{
(void)testcase;
testing_circuitset_t *cs = ptr;
int i;
for (i=0; i<3; ++i) {
circuit_free_(TO_CIRCUIT(cs->or_circ[i]));
}
circuit_free_(TO_CIRCUIT(cs->origin_circ));
tor_free(cs);
return 1;
}
static const struct testcase_setup_t relaycrypt_setup = {
testing_circuitset_setup, testing_circuitset_teardown
};
/* Test encrypting a cell to the final hop on a circuit, decrypting it
* at each hop, and recognizing it at the other end. Then do it again
* and again as the state evolves. */
static void
test_relaycrypt_outbound(void *arg)
{
testing_circuitset_t *cs = arg;
tt_assert(cs);
relay_header_t rh;
cell_t orig;
cell_t encrypted;
int i, j;
for (i = 0; i < 50; ++i) {
crypto_rand((char *)&orig, sizeof(orig));
relay_header_unpack(&rh, orig.payload);
rh.recognized = 0;
memset(rh.integrity, 0, sizeof(rh.integrity));
relay_header_pack(orig.payload, &rh);
memcpy(&encrypted, &orig, sizeof(orig));
/* Encrypt the cell to the last hop */
relay_encrypt_cell_outbound(&encrypted, cs->origin_circ,
cs->origin_circ->cpath->prev);
for (j = 0; j < 3; ++j) {
crypt_path_t *layer_hint = NULL;
char recognized = 0;
int r = relay_decrypt_cell(TO_CIRCUIT(cs->or_circ[j]),
&encrypted,
CELL_DIRECTION_OUT,
&layer_hint, &recognized);
tt_int_op(r, OP_EQ, 0);
tt_ptr_op(layer_hint, OP_EQ, NULL);
tt_int_op(recognized != 0, OP_EQ, j == 2);
}
tt_mem_op(orig.payload, OP_EQ, encrypted.payload, CELL_PAYLOAD_SIZE);
}
done:
;
}
/* As above, but simulate inbound cells from the last hop. */
static void
test_relaycrypt_inbound(void *arg)
{
testing_circuitset_t *cs = arg;
tt_assert(cs);
relay_header_t rh;
cell_t orig;
cell_t encrypted;
int i, j;
for (i = 0; i < 50; ++i) {
crypto_rand((char *)&orig, sizeof(orig));
relay_header_unpack(&rh, orig.payload);
rh.recognized = 0;
memset(rh.integrity, 0, sizeof(rh.integrity));
relay_header_pack(orig.payload, &rh);
memcpy(&encrypted, &orig, sizeof(orig));
/* Encrypt the cell to the last hop */
relay_encrypt_cell_inbound(&encrypted, cs->or_circ[2]);
crypt_path_t *layer_hint = NULL;
char recognized = 0;
int r;
for (j = 1; j >= 0; --j) {
r = relay_decrypt_cell(TO_CIRCUIT(cs->or_circ[j]),
&encrypted,
CELL_DIRECTION_IN,
&layer_hint, &recognized);
tt_int_op(r, OP_EQ, 0);
tt_ptr_op(layer_hint, OP_EQ, NULL);
tt_int_op(recognized, OP_EQ, 0);
}
relay_decrypt_cell(TO_CIRCUIT(cs->origin_circ),
&encrypted,
CELL_DIRECTION_IN,
&layer_hint, &recognized);
tt_int_op(r, OP_EQ, 0);
tt_int_op(recognized, OP_EQ, 1);
tt_ptr_op(layer_hint, OP_EQ, cs->origin_circ->cpath->prev);
tt_mem_op(orig.payload, OP_EQ, encrypted.payload, CELL_PAYLOAD_SIZE);
}
done:
;
}
#define TEST(name) \
{ # name, test_relaycrypt_ ## name, 0, &relaycrypt_setup, NULL }
struct testcase_t relaycrypt_tests[] = {
TEST(outbound),
TEST(inbound),
END_OF_TESTCASES
};