Merge remote-tracking branch 'public/bug9841_025'

This commit is contained in:
Nick Mathewson 2014-04-08 12:06:03 -04:00
commit fffc59b0e9
6 changed files with 275 additions and 39 deletions

7
changes/bug9841 Normal file
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@ -0,0 +1,7 @@
o Minor features (performance):
- Faster server-side lookups of rendezvous and introduction point
circuits by using hashtables instead of linear searches over all
the circuits. These functions previously accounted between 3 and
7% of CPU usage on some busy relays.

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@ -32,6 +32,7 @@
#include "rephist.h"
#include "routerlist.h"
#include "routerset.h"
#include "ht.h"
/********* START VARIABLES **********/
@ -45,6 +46,9 @@ static smartlist_t *circuits_pending_chans = NULL;
static void circuit_free_cpath_node(crypt_path_t *victim);
static void cpath_ref_decref(crypt_path_reference_t *cpath_ref);
//static void circuit_set_rend_token(or_circuit_t *circ, int is_rend_circ,
// const uint8_t *token);
static void circuit_clear_rend_token(or_circuit_t *circ);
/********* END VARIABLES ************/
@ -756,6 +760,8 @@ circuit_free(circuit_t *circ)
crypto_cipher_free(ocirc->n_crypto);
crypto_digest_free(ocirc->n_digest);
circuit_clear_rend_token(ocirc);
if (ocirc->rend_splice) {
or_circuit_t *other = ocirc->rend_splice;
tor_assert(other->base_.magic == OR_CIRCUIT_MAGIC);
@ -1229,43 +1235,167 @@ circuit_get_next_by_pk_and_purpose(origin_circuit_t *start,
return NULL;
}
/** Return the first OR circuit in the global list whose purpose is
* <b>purpose</b>, and whose rend_token is the <b>len</b>-byte
* <b>token</b>. */
/** Map from rendezvous cookie to or_circuit_t */
static digestmap_t *rend_cookie_map = NULL;
/** Map from introduction point digest to or_circuit_t */
static digestmap_t *intro_digest_map = NULL;
/** Return the OR circuit whose purpose is <b>purpose</b>, and whose
* rend_token is the REND_TOKEN_LEN-byte <b>token</b>. If <b>is_rend_circ</b>,
* look for rendezvous point circuits; otherwise look for introduction point
* circuits. */
static or_circuit_t *
circuit_get_by_rend_token_and_purpose(uint8_t purpose, const char *token,
size_t len)
circuit_get_by_rend_token_and_purpose(uint8_t purpose, int is_rend_circ,
const char *token)
{
circuit_t *circ;
TOR_LIST_FOREACH(circ, &global_circuitlist, head) {
if (! circ->marked_for_close &&
circ->purpose == purpose &&
tor_memeq(TO_OR_CIRCUIT(circ)->rend_token, token, len))
return TO_OR_CIRCUIT(circ);
or_circuit_t *circ;
digestmap_t *map = is_rend_circ ? rend_cookie_map : intro_digest_map;
if (!map)
return NULL;
circ = digestmap_get(map, token);
if (!circ ||
circ->base_.purpose != purpose ||
circ->base_.marked_for_close)
return NULL;
if (!circ->rendinfo ||
! bool_eq(circ->rendinfo->is_rend_circ, is_rend_circ) ||
tor_memneq(circ->rendinfo->rend_token, token, REND_TOKEN_LEN)) {
char *t = tor_strdup(hex_str(token, REND_TOKEN_LEN));
log_warn(LD_BUG, "Wanted a circuit with %s:%d, but lookup returned %s:%d",
safe_str(t), is_rend_circ,
safe_str(hex_str(circ->rendinfo->rend_token, REND_TOKEN_LEN)),
(int)circ->rendinfo->is_rend_circ);
tor_free(t);
return NULL;
}
return NULL;
return circ;
}
/** Clear the rendezvous cookie or introduction point key digest that's
* configured on <b>circ</b>, if any, and remove it from any such maps. */
static void
circuit_clear_rend_token(or_circuit_t *circ)
{
or_circuit_t *found_circ;
digestmap_t *map;
if (!circ || !circ->rendinfo)
return;
map = circ->rendinfo->is_rend_circ ? rend_cookie_map : intro_digest_map;
if (!map) {
log_warn(LD_BUG, "Tried to clear rend token on circuit, but found no map");
return;
}
found_circ = digestmap_get(map, circ->rendinfo->rend_token);
if (found_circ == circ) {
/* Great, this is the right one. */
digestmap_remove(map, circ->rendinfo->rend_token);
} else if (found_circ) {
log_warn(LD_BUG, "Tried to clear rend token on circuit, but "
"it was already replaced in the map.");
} else {
log_warn(LD_BUG, "Tried to clear rend token on circuit, but "
"it not in the map at all.");
}
tor_free(circ->rendinfo); /* Sets it to NULL too */
}
/** Set the rendezvous cookie (if is_rend_circ), or the introduction point
* digest (if ! is_rend_circ) of <b>circ</b> to the REND_TOKEN_LEN-byte value
* in <b>token</b>, and add it to the appropriate map. If it previously had a
* token, clear it. If another circuit previously had the same
* cookie/intro-digest, mark that circuit and remove it from the map. */
static void
circuit_set_rend_token(or_circuit_t *circ, int is_rend_circ,
const uint8_t *token)
{
digestmap_t **map_p, *map;
or_circuit_t *found_circ;
/* Find the right map, creating it as needed */
map_p = is_rend_circ ? &rend_cookie_map : &intro_digest_map;
if (!*map_p)
*map_p = digestmap_new();
map = *map_p;
/* If this circuit already has a token, we need to remove that. */
if (circ->rendinfo)
circuit_clear_rend_token(circ);
if (token == NULL) {
/* We were only trying to remove this token, not set a new one. */
return;
}
found_circ = digestmap_get(map, (const char *)token);
if (found_circ) {
tor_assert(found_circ != circ);
circuit_clear_rend_token(found_circ);
if (! found_circ->base_.marked_for_close) {
circuit_mark_for_close(TO_CIRCUIT(found_circ), END_CIRC_REASON_FINISHED);
if (is_rend_circ) {
log_fn(LOG_PROTOCOL_WARN, LD_REND,
"Duplicate rendezvous cookie (%s...) used on two circuits",
hex_str((const char*)token, 4)); /* only log first 4 chars */
}
}
}
/* Now set up the rendinfo */
circ->rendinfo = tor_malloc(sizeof(*circ->rendinfo));
memcpy(circ->rendinfo->rend_token, token, REND_TOKEN_LEN);
circ->rendinfo->is_rend_circ = is_rend_circ ? 1 : 0;
digestmap_set(map, (const char *)token, circ);
}
/** Return the circuit waiting for a rendezvous with the provided cookie.
* Return NULL if no such circuit is found.
*/
or_circuit_t *
circuit_get_rendezvous(const char *cookie)
circuit_get_rendezvous(const uint8_t *cookie)
{
return circuit_get_by_rend_token_and_purpose(
CIRCUIT_PURPOSE_REND_POINT_WAITING,
cookie, REND_COOKIE_LEN);
1, (const char*)cookie);
}
/** Return the circuit waiting for intro cells of the given digest.
* Return NULL if no such circuit is found.
*/
or_circuit_t *
circuit_get_intro_point(const char *digest)
circuit_get_intro_point(const uint8_t *digest)
{
return circuit_get_by_rend_token_and_purpose(
CIRCUIT_PURPOSE_INTRO_POINT, digest,
DIGEST_LEN);
CIRCUIT_PURPOSE_INTRO_POINT, 0,
(const char *)digest);
}
/** Set the rendezvous cookie of <b>circ</b> to <b>cookie</b>. If another
* circuit previously had that cookie, mark it. */
void
circuit_set_rendezvous_cookie(or_circuit_t *circ, const uint8_t *cookie)
{
circuit_set_rend_token(circ, 1, cookie);
}
/** Set the intro point key digest of <b>circ</b> to <b>cookie</b>. If another
* circuit previously had that intro point digest, mark it. */
void
circuit_set_intro_point_digest(or_circuit_t *circ, const uint8_t *digest)
{
circuit_set_rend_token(circ, 0, digest);
}
/** Return a circuit that is open, is CIRCUIT_PURPOSE_C_GENERAL,

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@ -46,8 +46,10 @@ origin_circuit_t *circuit_get_ready_rend_circ_by_rend_data(
const rend_data_t *rend_data);
origin_circuit_t *circuit_get_next_by_pk_and_purpose(origin_circuit_t *start,
const char *digest, uint8_t purpose);
or_circuit_t *circuit_get_rendezvous(const char *cookie);
or_circuit_t *circuit_get_intro_point(const char *digest);
or_circuit_t *circuit_get_rendezvous(const uint8_t *cookie);
or_circuit_t *circuit_get_intro_point(const uint8_t *digest);
void circuit_set_rendezvous_cookie(or_circuit_t *circ, const uint8_t *cookie);
void circuit_set_intro_point_digest(or_circuit_t *circ, const uint8_t *digest);
origin_circuit_t *circuit_find_to_cannibalize(uint8_t purpose,
extend_info_t *info, int flags);
void circuit_mark_all_unused_circs(void);

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@ -3174,20 +3174,8 @@ typedef struct or_circuit_t {
* is not marked for close. */
struct or_circuit_t *rend_splice;
#if REND_COOKIE_LEN >= DIGEST_LEN
#define REND_TOKEN_LEN REND_COOKIE_LEN
#else
#define REND_TOKEN_LEN DIGEST_LEN
#endif
struct or_circuit_rendinfo_s *rendinfo;
/** A hash of location-hidden service's PK if purpose is INTRO_POINT, or a
* rendezvous cookie if purpose is REND_POINT_WAITING. Filled with zeroes
* otherwise.
* ???? move to a subtype or adjunct structure? Wastes 20 bytes. -NM
*/
char rend_token[REND_TOKEN_LEN];
/* ???? move to a subtype or adjunct structure? Wastes 20 bytes -NM */
/** Stores KH for the handshake. */
char rend_circ_nonce[DIGEST_LEN];/* KH in tor-spec.txt */
@ -3214,6 +3202,25 @@ typedef struct or_circuit_t {
uint32_t max_middle_cells;
} or_circuit_t;
typedef struct or_circuit_rendinfo_s {
#if REND_COOKIE_LEN != DIGEST_LEN
#error "The REND_TOKEN_LEN macro assumes REND_COOKIE_LEN == DIGEST_LEN"
#endif
#define REND_TOKEN_LEN DIGEST_LEN
/** A hash of location-hidden service's PK if purpose is INTRO_POINT, or a
* rendezvous cookie if purpose is REND_POINT_WAITING. Filled with zeroes
* otherwise.
*/
char rend_token[REND_TOKEN_LEN];
/** True if this is a rendezvous point circuit; false if this is an
* introduction point. */
unsigned is_rend_circ;
} or_circuit_rendinfo_t;
/** Convert a circuit subtype to a circuit_t. */
#define TO_CIRCUIT(x) (&((x)->base_))

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@ -94,7 +94,7 @@ rend_mid_establish_intro(or_circuit_t *circ, const uint8_t *request,
/* Close any other intro circuits with the same pk. */
c = NULL;
while ((c = circuit_get_intro_point(pk_digest))) {
while ((c = circuit_get_intro_point((const uint8_t *)pk_digest))) {
log_info(LD_REND, "Replacing old circuit for service %s",
safe_str(serviceid));
circuit_mark_for_close(TO_CIRCUIT(c), END_CIRC_REASON_FINISHED);
@ -111,7 +111,7 @@ rend_mid_establish_intro(or_circuit_t *circ, const uint8_t *request,
/* Now, set up this circuit. */
circuit_change_purpose(TO_CIRCUIT(circ), CIRCUIT_PURPOSE_INTRO_POINT);
memcpy(circ->rend_token, pk_digest, DIGEST_LEN);
circuit_set_intro_point_digest(circ, (uint8_t *)pk_digest);
log_info(LD_REND,
"Established introduction point on circuit %u for service %s",
@ -165,7 +165,7 @@ rend_mid_introduce(or_circuit_t *circ, const uint8_t *request,
(char*)request, REND_SERVICE_ID_LEN);
/* The first 20 bytes are all we look at: they have a hash of Bob's PK. */
intro_circ = circuit_get_intro_point((char*)request);
intro_circ = circuit_get_intro_point((const uint8_t*)request);
if (!intro_circ) {
log_info(LD_REND,
"No intro circ found for INTRODUCE1 cell (%s) from circuit %u; "
@ -236,7 +236,7 @@ rend_mid_establish_rendezvous(or_circuit_t *circ, const uint8_t *request,
goto err;
}
if (circuit_get_rendezvous((char*)request)) {
if (circuit_get_rendezvous(request)) {
log_warn(LD_PROTOCOL,
"Duplicate rendezvous cookie in ESTABLISH_RENDEZVOUS.");
goto err;
@ -252,7 +252,7 @@ rend_mid_establish_rendezvous(or_circuit_t *circ, const uint8_t *request,
}
circuit_change_purpose(TO_CIRCUIT(circ), CIRCUIT_PURPOSE_REND_POINT_WAITING);
memcpy(circ->rend_token, request, REND_COOKIE_LEN);
circuit_set_rendezvous_cookie(circ, request);
base16_encode(hexid,9,(char*)request,4);
@ -300,7 +300,7 @@ rend_mid_rendezvous(or_circuit_t *circ, const uint8_t *request,
"Got request for rendezvous from circuit %u to cookie %s.",
(unsigned)circ->p_circ_id, hexid);
rend_circ = circuit_get_rendezvous((char*)request);
rend_circ = circuit_get_rendezvous(request);
if (!rend_circ) {
log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
"Rejecting RENDEZVOUS1 cell with unrecognized rendezvous cookie %s.",
@ -328,7 +328,7 @@ rend_mid_rendezvous(or_circuit_t *circ, const uint8_t *request,
circuit_change_purpose(TO_CIRCUIT(circ), CIRCUIT_PURPOSE_REND_ESTABLISHED);
circuit_change_purpose(TO_CIRCUIT(rend_circ),
CIRCUIT_PURPOSE_REND_ESTABLISHED);
memset(circ->rend_token, 0, REND_COOKIE_LEN);
circuit_set_rendezvous_cookie(circ, NULL);
rend_circ->rend_splice = circ;
circ->rend_splice = rend_circ;

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@ -161,8 +161,98 @@ test_clist_maps(void *arg)
UNMOCK(circuitmux_detach_circuit);
}
static void
test_rend_token_maps(void *arg)
{
or_circuit_t *c1, *c2, *c3, *c4;
const uint8_t tok1[REND_TOKEN_LEN] = "The cat can't tell y";
const uint8_t tok2[REND_TOKEN_LEN] = "ou its name, and it ";
const uint8_t tok3[REND_TOKEN_LEN] = "doesn't really care.";
/* -- Adapted from a quote by Fredrik Lundh. */
(void)arg;
(void)tok1; //xxxx
c1 = or_circuit_new(0, NULL);
c2 = or_circuit_new(0, NULL);
c3 = or_circuit_new(0, NULL);
c4 = or_circuit_new(0, NULL);
tt_int_op(strlen((char*)tok1), ==, REND_TOKEN_LEN);
/* No maps; nothing there. */
tt_ptr_op(NULL, ==, circuit_get_rendezvous(tok1));
tt_ptr_op(NULL, ==, circuit_get_intro_point(tok1));
circuit_set_rendezvous_cookie(c1, tok1);
circuit_set_intro_point_digest(c2, tok2);
tt_ptr_op(NULL, ==, circuit_get_rendezvous(tok3));
tt_ptr_op(NULL, ==, circuit_get_intro_point(tok3));
tt_ptr_op(NULL, ==, circuit_get_rendezvous(tok2));
tt_ptr_op(NULL, ==, circuit_get_intro_point(tok1));
/* Without purpose set, we don't get the circuits */
tt_ptr_op(NULL, ==, circuit_get_rendezvous(tok1));
tt_ptr_op(NULL, ==, circuit_get_intro_point(tok2));
c1->base_.purpose = CIRCUIT_PURPOSE_REND_POINT_WAITING;
c2->base_.purpose = CIRCUIT_PURPOSE_INTRO_POINT;
/* Okay, make sure they show up now. */
tt_ptr_op(c1, ==, circuit_get_rendezvous(tok1));
tt_ptr_op(c2, ==, circuit_get_intro_point(tok2));
/* Two items at the same place with the same token. */
c3->base_.purpose = CIRCUIT_PURPOSE_REND_POINT_WAITING;
circuit_set_rendezvous_cookie(c3, tok2);
tt_ptr_op(c2, ==, circuit_get_intro_point(tok2));
tt_ptr_op(c3, ==, circuit_get_rendezvous(tok2));
/* Marking a circuit makes it not get returned any more */
circuit_mark_for_close(TO_CIRCUIT(c1), END_CIRC_REASON_FINISHED);
tt_ptr_op(NULL, ==, circuit_get_rendezvous(tok1));
circuit_free(TO_CIRCUIT(c1));
c1 = NULL;
/* Freeing a circuit makes it not get returned any more. */
circuit_free(TO_CIRCUIT(c2));
c2 = NULL;
tt_ptr_op(NULL, ==, circuit_get_intro_point(tok2));
/* c3 -- are you still there? */
tt_ptr_op(c3, ==, circuit_get_rendezvous(tok2));
/* Change its cookie. This never happens in Tor per se, but hey. */
c3->base_.purpose = CIRCUIT_PURPOSE_INTRO_POINT;
circuit_set_intro_point_digest(c3, tok3);
tt_ptr_op(NULL, ==, circuit_get_rendezvous(tok2));
tt_ptr_op(c3, ==, circuit_get_intro_point(tok3));
/* Now replace c3 with c4. */
c4->base_.purpose = CIRCUIT_PURPOSE_INTRO_POINT;
circuit_set_intro_point_digest(c4, tok3);
tt_ptr_op(c4, ==, circuit_get_intro_point(tok3));
tt_ptr_op(c3->rendinfo, ==, NULL);
tt_ptr_op(c4->rendinfo, !=, NULL);
test_mem_op(c4->rendinfo, ==, tok3, REND_TOKEN_LEN);
/* Now clear c4's cookie. */
circuit_set_intro_point_digest(c4, NULL);
tt_ptr_op(c4->rendinfo, ==, NULL);
tt_ptr_op(NULL, ==, circuit_get_intro_point(tok3));
done:
circuit_free(TO_CIRCUIT(c1));
circuit_free(TO_CIRCUIT(c2));
circuit_free(TO_CIRCUIT(c3));
circuit_free(TO_CIRCUIT(c4));
}
struct testcase_t circuitlist_tests[] = {
{ "maps", test_clist_maps, TT_FORK, NULL, NULL },
{ "rend_token_maps", test_rend_token_maps, TT_FORK, NULL, NULL },
END_OF_TESTCASES
};