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-rw-r--r--src/ipcpd/unicast/dht.c2775
1 files changed, 0 insertions, 2775 deletions
diff --git a/src/ipcpd/unicast/dht.c b/src/ipcpd/unicast/dht.c
deleted file mode 100644
index f7cb89f2..00000000
--- a/src/ipcpd/unicast/dht.c
+++ /dev/null
@@ -1,2775 +0,0 @@
-/*
- * Ouroboros - Copyright (C) 2016 - 2021
- *
- * Distributed Hash Table based on Kademlia
- *
- * Dimitri Staessens <dimitri@ouroboros.rocks>
- * Sander Vrijders <sander@ouroboros.rocks>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public License
- * version 2.1 as published by the Free Software Foundation.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., http://www.fsf.org/about/contact/.
- */
-
-#if defined(__linux__) || defined(__CYGWIN__)
-#define _DEFAULT_SOURCE
-#else
-#define _POSIX_C_SOURCE 200112L
-#endif
-
-#include "config.h"
-
-#define DHT "dht"
-#define OUROBOROS_PREFIX DHT
-
-#include <ouroboros/hash.h>
-#include <ouroboros/ipcp-dev.h>
-#include <ouroboros/bitmap.h>
-#include <ouroboros/errno.h>
-#include <ouroboros/logs.h>
-#include <ouroboros/list.h>
-#include <ouroboros/notifier.h>
-#include <ouroboros/random.h>
-#include <ouroboros/time_utils.h>
-#include <ouroboros/tpm.h>
-#include <ouroboros/utils.h>
-#include <ouroboros/pthread.h>
-
-#include "common/connmgr.h"
-#include "dht.h"
-#include "dt.h"
-#include "ipcp.h"
-
-#include <stdlib.h>
-#include <string.h>
-#include <assert.h>
-#include <inttypes.h>
-#include <limits.h>
-
-#include "kademlia.pb-c.h"
-typedef KadMsg kad_msg_t;
-typedef KadContactMsg kad_contact_msg_t;
-
-#ifndef CLOCK_REALTIME_COARSE
-#define CLOCK_REALTIME_COARSE CLOCK_REALTIME
-#endif
-
-#define DHT_MAX_REQS 2048 /* KAD recommends rnd(), bmp can be changed. */
-#define KAD_ALPHA 3 /* Parallel factor, proven optimal value. */
-#define KAD_K 8 /* Replication factor, MDHT value. */
-#define KAD_T_REPL 900 /* Replication time, tied to k. MDHT value. */
-#define KAD_T_REFR 900 /* Refresh time stale bucket, MDHT value. */
-#define KAD_T_JOIN 8 /* Response time to wait for a join. */
-#define KAD_T_RESP 5 /* Response time to wait for a response. */
-#define KAD_R_PING 2 /* Ping retries before declaring peer dead. */
-#define KAD_QUEER 15 /* Time to declare peer questionable. */
-#define KAD_BETA 8 /* Bucket split factor, must be 1, 2, 4 or 8. */
-#define KAD_RESP_RETR 6 /* Number of retries on sending a response. */
-#define KAD_JOIN_RETR 8 /* Number of retries sending a join. */
-#define KAD_JOIN_INTV 1 /* Time (seconds) between join retries. */
-#define HANDLE_TIMEO 1000 /* Timeout for dht_handle_packet tpm check (ms) */
-#define DHT_RETR_ADDR 1 /* Number of addresses to return on retrieve */
-
-enum dht_state {
- DHT_INIT = 0,
- DHT_SHUTDOWN,
- DHT_JOINING,
- DHT_RUNNING,
-};
-
-enum kad_code {
- KAD_JOIN = 0,
- KAD_FIND_NODE,
- KAD_FIND_VALUE,
- /* Messages without a response below. */
- KAD_STORE,
- KAD_RESPONSE
-};
-
-enum kad_req_state {
- REQ_NULL = 0,
- REQ_INIT,
- REQ_PENDING,
- REQ_RESPONSE,
- REQ_DONE,
- REQ_DESTROY
-};
-
-enum lookup_state {
- LU_NULL = 0,
- LU_INIT,
- LU_PENDING,
- LU_UPDATE,
- LU_COMPLETE,
- LU_DESTROY
-};
-
-struct kad_req {
- struct list_head next;
-
- uint32_t cookie;
- enum kad_code code;
- uint8_t * key;
- uint64_t addr;
-
- enum kad_req_state state;
- pthread_cond_t cond;
- pthread_mutex_t lock;
-
- time_t t_exp;
-};
-
-struct cookie_el {
- struct list_head next;
-
- uint32_t cookie;
-};
-
-struct lookup {
- struct list_head next;
-
- struct list_head cookies;
-
- uint8_t * key;
-
- struct list_head contacts;
- size_t n_contacts;
-
- uint64_t * addrs;
- size_t n_addrs;
-
- enum lookup_state state;
- pthread_cond_t cond;
- pthread_mutex_t lock;
-};
-
-struct val {
- struct list_head next;
-
- uint64_t addr;
-
- time_t t_exp;
- time_t t_rep;
-};
-
-struct ref_entry {
- struct list_head next;
-
- uint8_t * key;
-
- time_t t_rep;
-};
-
-struct dht_entry {
- struct list_head next;
-
- uint8_t * key;
- size_t n_vals;
- struct list_head vals;
-};
-
-struct contact {
- struct list_head next;
-
- uint8_t * id;
- uint64_t addr;
-
- size_t fails;
- time_t t_seen;
-};
-
-struct bucket {
- struct list_head contacts;
- size_t n_contacts;
-
- struct list_head alts;
- size_t n_alts;
-
- time_t t_refr;
-
- size_t depth;
- uint8_t mask;
-
- struct bucket * parent;
- struct bucket * children[1L << KAD_BETA];
-};
-
-struct cmd {
- struct list_head next;
-
- struct shm_du_buff * sdb;
-};
-
-struct {
- size_t alpha;
- size_t b;
- size_t k;
-
- time_t t_expire;
- time_t t_refresh;
- time_t t_replic;
- time_t t_repub;
-
- uint8_t * id;
- uint64_t addr;
-
- struct bucket * buckets;
-
- struct list_head entries;
-
- struct list_head refs;
-
- struct list_head lookups;
-
- struct list_head requests;
- struct bmp * cookies;
-
- enum dht_state state;
- struct list_head cmds;
- pthread_cond_t cond;
- pthread_mutex_t mtx;
-
- pthread_rwlock_t lock;
-
- uint64_t eid;
-
- struct tpm * tpm;
-
- pthread_t worker;
-} dht;
-
-struct join_info {
- uint64_t addr;
-};
-
-struct packet_info {
- struct shm_du_buff * sdb;
-};
-
-static uint8_t * dht_dup_key(const uint8_t * key,
- size_t len)
-{
- uint8_t * dup;
-
- dup = malloc(sizeof(*dup) * len);
- if (dup == NULL)
- return NULL;
-
- memcpy(dup, key, len);
-
- return dup;
-}
-
-static enum dht_state dht_get_state(void)
-{
- enum dht_state state;
-
- pthread_mutex_lock(&dht.mtx);
-
- state = dht.state;
-
- pthread_mutex_unlock(&dht.mtx);
-
- return state;
-}
-
-static int dht_set_state(enum dht_state state)
-{
- pthread_mutex_lock(&dht.mtx);
-
- if (state == DHT_JOINING && dht.state != DHT_INIT) {
- pthread_mutex_unlock(&dht.mtx);
- return -1;
- }
-
- dht.state = state;
-
- pthread_cond_broadcast(&dht.cond);
-
- pthread_mutex_unlock(&dht.mtx);
-
- return 0;
-}
-
-int dht_wait_running()
-{
- int ret = 0;
-
- pthread_mutex_lock(&dht.mtx);
-
- pthread_cleanup_push(__cleanup_mutex_unlock, &dht.mtx);
-
- while (dht.state == DHT_JOINING)
- pthread_cond_wait(&dht.cond, &dht.mtx);
-
- if (dht.state != DHT_RUNNING)
- ret = -1;
-
- pthread_cleanup_pop(true);
-
- return ret;
-}
-
-static uint8_t * create_id(size_t len)
-{
- uint8_t * id;
-
- id = malloc(len);
- if (id == NULL)
- return NULL;
-
- if (random_buffer(id, len) < 0) {
- free(id);
- return NULL;
- }
-
- return id;
-}
-
-static void kad_req_create(kad_msg_t * msg,
- uint64_t addr)
-{
- struct kad_req * req;
- pthread_condattr_t cattr;
- struct timespec t;
- size_t b;
-
- req = malloc(sizeof(*req));
- if (req == NULL)
- return;
-
- list_head_init(&req->next);
-
- clock_gettime(CLOCK_REALTIME_COARSE, &t);
-
- req->t_exp = t.tv_sec + KAD_T_RESP;
- req->addr = addr;
- req->state = REQ_INIT;
- req->cookie = msg->cookie;
- req->code = msg->code;
- req->key = NULL;
-
- pthread_rwlock_rdlock(&dht.lock);
- b = dht.b;
- pthread_rwlock_unlock(&dht.lock);
-
- if (msg->has_key) {
- req->key = dht_dup_key(msg->key.data, b);
- if (req->key == NULL) {
- free(req);
- return;
- }
- }
-
- if (pthread_mutex_init(&req->lock, NULL)) {
- free(req->key);
- free(req);
- return;
- }
-
- pthread_condattr_init(&cattr);
-#ifndef __APPLE__
- pthread_condattr_setclock(&cattr, PTHREAD_COND_CLOCK);
-#endif
-
- if (pthread_cond_init(&req->cond, &cattr)) {
- pthread_condattr_destroy(&cattr);
- pthread_mutex_destroy(&req->lock);
- free(req->key);
- free(req);
- return;
- }
-
- pthread_condattr_destroy(&cattr);
-
- pthread_rwlock_wrlock(&dht.lock);
-
- list_add(&req->next, &dht.requests);
-
- pthread_rwlock_unlock(&dht.lock);
-}
-
-static void cancel_req_destroy(void * o)
-{
- struct kad_req * req = (struct kad_req *) o;
-
- pthread_mutex_unlock(&req->lock);
-
- pthread_cond_destroy(&req->cond);
- pthread_mutex_destroy(&req->lock);
-
- if (req->key != NULL)
- free(req->key);
-
- free(req);
-}
-
-static void kad_req_destroy(struct kad_req * req)
-{
- assert(req);
-
- pthread_mutex_lock(&req->lock);
-
- switch (req->state) {
- case REQ_DESTROY:
- pthread_mutex_unlock(&req->lock);
- return;
- case REQ_PENDING:
- req->state = REQ_DESTROY;
- pthread_cond_signal(&req->cond);
- break;
- case REQ_INIT:
- case REQ_DONE:
- req->state = REQ_NULL;
- break;
- case REQ_RESPONSE:
- case REQ_NULL:
- default:
- break;
- }
-
- pthread_cleanup_push(cancel_req_destroy, req);
-
- while (req->state != REQ_NULL && req->state != REQ_DONE)
- pthread_cond_wait(&req->cond, &req->lock);
-
- pthread_cleanup_pop(true);
-}
-
-static int kad_req_wait(struct kad_req * req,
- time_t t)
-{
- struct timespec timeo = {t, 0};
- struct timespec abs;
- int ret = 0;
-
- assert(req);
-
- clock_gettime(PTHREAD_COND_CLOCK, &abs);
-
- ts_add(&abs, &timeo, &abs);
-
- pthread_mutex_lock(&req->lock);
-
- req->state = REQ_PENDING;
-
- pthread_cleanup_push(__cleanup_mutex_unlock, &req->lock);
-
- while (req->state == REQ_PENDING && ret != -ETIMEDOUT)
- ret = -pthread_cond_timedwait(&req->cond, &req->lock, &abs);
-
- switch(req->state) {
- case REQ_DESTROY:
- ret = -1;
- req->state = REQ_NULL;
- pthread_cond_signal(&req->cond);
- break;
- case REQ_PENDING: /* ETIMEDOUT */
- case REQ_RESPONSE:
- req->state = REQ_DONE;
- pthread_cond_broadcast(&req->cond);
- break;
- default:
- break;
- }
-
- pthread_cleanup_pop(true);
-
- return ret;
-}
-
-static void kad_req_respond(struct kad_req * req)
-{
- pthread_mutex_lock(&req->lock);
-
- req->state = REQ_RESPONSE;
- pthread_cond_signal(&req->cond);
-
- pthread_mutex_unlock(&req->lock);
-}
-
-static struct contact * contact_create(const uint8_t * id,
- size_t len,
- uint64_t addr)
-{
- struct contact * c;
- struct timespec t;
-
- c = malloc(sizeof(*c));
- if (c == NULL)
- return NULL;
-
- list_head_init(&c->next);
-
- clock_gettime(CLOCK_REALTIME_COARSE, &t);
-
- c->addr = addr;
- c->fails = 0;
- c->t_seen = t.tv_sec;
- c->id = dht_dup_key(id, len);
- if (c->id == NULL) {
- free(c);
- return NULL;
- }
-
- return c;
-}
-
-static void contact_destroy(struct contact * c)
-{
- if (c != NULL)
- free(c->id);
-
- free(c);
-}
-
-static struct bucket * iter_bucket(struct bucket * b,
- const uint8_t * id)
-{
- uint8_t byte;
- uint8_t mask;
-
- assert(b);
-
- if (b->children[0] == NULL)
- return b;
-
- byte = id[(b->depth * KAD_BETA) / CHAR_BIT];
-
- mask = ((1L << KAD_BETA) - 1) & 0xFF;
-
- byte >>= (CHAR_BIT - KAD_BETA) -
- (((b->depth) * KAD_BETA) & (CHAR_BIT - 1));
-
- return iter_bucket(b->children[(byte & mask)], id);
-}
-
-static struct bucket * dht_get_bucket(const uint8_t * id)
-{
- assert(dht.buckets);
-
- return iter_bucket(dht.buckets, id);
-}
-
-/*
- * If someone builds a network where the n (n > k) closest nodes all
- * have IDs starting with the same 64 bits: by all means, change this.
- */
-static uint64_t dist(const uint8_t * src,
- const uint8_t * dst)
-{
- return betoh64(*((uint64_t *) src) ^ *((uint64_t *) dst));
-}
-
-static size_t list_add_sorted(struct list_head * l,
- struct contact * c,
- const uint8_t * key)
-{
- struct list_head * p;
-
- assert(l);
- assert(c);
- assert(key);
- assert(c->id);
-
- list_for_each(p, l) {
- struct contact * e = list_entry(p, struct contact, next);
- if (dist(c->id, key) > dist(e->id, key))
- break;
- }
-
- list_add_tail(&c->next, p);
-
- return 1;
-}
-
-static size_t dht_contact_list(struct list_head * l,
- const uint8_t * key)
-{
- struct list_head * p;
- struct bucket * b;
- size_t len = 0;
- size_t i;
- struct timespec t;
-
- assert(l);
- assert(key);
- assert(list_is_empty(l));
-
- clock_gettime(CLOCK_REALTIME_COARSE, &t);
-
- b = dht_get_bucket(key);
- if (b == NULL)
- return 0;
-
- b->t_refr = t.tv_sec + KAD_T_REFR;
-
- if (b->n_contacts == dht.k || b->parent == NULL) {
- list_for_each(p, &b->contacts) {
- struct contact * c;
- c = list_entry(p, struct contact, next);
- c = contact_create(c->id, dht.b, c->addr);
- if (list_add_sorted(l, c, key) == 1)
- if (++len == dht.k)
- break;
- }
- } else {
- struct bucket * d = b->parent;
- for (i = 0; i < (1L << KAD_BETA) && len < dht.k; ++i) {
- list_for_each(p, &d->children[i]->contacts) {
- struct contact * c;
- c = list_entry(p, struct contact, next);
- c = contact_create(c->id, dht.b, c->addr);
- if (c == NULL)
- continue;
- if (list_add_sorted(l, c, key) == 1)
- if (++len == dht.k)
- break;
- }
- }
- }
-
- assert(len == dht.k || b->parent == NULL);
-
- return len;
-}
-
-static struct lookup * lookup_create(const uint8_t * id)
-{
- struct lookup * lu;
- pthread_condattr_t cattr;
-
- assert(id);
-
- lu = malloc(sizeof(*lu));
- if (lu == NULL)
- goto fail_malloc;
-
- list_head_init(&lu->contacts);
- list_head_init(&lu->cookies);
-
- lu->state = LU_INIT;
- lu->addrs = NULL;
- lu->n_addrs = 0;
- lu->key = dht_dup_key(id, dht.b);
- if (lu->key == NULL)
- goto fail_id;
-
- if (pthread_mutex_init(&lu->lock, NULL))
- goto fail_mutex;
-
- pthread_condattr_init(&cattr);
-#ifndef __APPLE__
- pthread_condattr_setclock(&cattr, PTHREAD_COND_CLOCK);
-#endif
-
- if (pthread_cond_init(&lu->cond, &cattr))
- goto fail_cond;
-
- pthread_condattr_destroy(&cattr);
-
- pthread_rwlock_wrlock(&dht.lock);
-
- list_add(&lu->next, &dht.lookups);
-
- lu->n_contacts = dht_contact_list(&lu->contacts, id);
-
- pthread_rwlock_unlock(&dht.lock);
-
- return lu;
-
- fail_cond:
- pthread_condattr_destroy(&cattr);
- pthread_mutex_destroy(&lu->lock);
- fail_mutex:
- free(lu->key);
- fail_id:
- free(lu);
- fail_malloc:
- return NULL;
-}
-
-static void cancel_lookup_destroy(void * o)
-{
- struct lookup * lu;
- struct list_head * p;
- struct list_head * h;
-
- lu = (struct lookup *) o;
-
- if (lu->key != NULL)
- free(lu->key);
- if (lu->addrs != NULL)
- free(lu->addrs);
-
- list_for_each_safe(p, h, &lu->contacts) {
- struct contact * c = list_entry(p, struct contact, next);
- list_del(&c->next);
- contact_destroy(c);
- }
-
- list_for_each_safe(p, h, &lu->cookies) {
- struct cookie_el * c = list_entry(p, struct cookie_el, next);
- list_del(&c->next);
- free(c);
- }
-
- pthread_mutex_unlock(&lu->lock);
-
- pthread_mutex_destroy(&lu->lock);
-
- free(lu);
-}
-
-static void lookup_destroy(struct lookup * lu)
-{
- assert(lu);
-
- pthread_mutex_lock(&lu->lock);
-
- switch (lu->state) {
- case LU_DESTROY:
- pthread_mutex_unlock(&lu->lock);
- return;
- case LU_PENDING:
- lu->state = LU_DESTROY;
- pthread_cond_broadcast(&lu->cond);
- break;
- case LU_INIT:
- case LU_UPDATE:
- case LU_COMPLETE:
- lu->state = LU_NULL;
- break;
- case LU_NULL:
- default:
- break;
- }
-
- pthread_cleanup_push(cancel_lookup_destroy, lu);
-
- while (lu->state != LU_NULL)
- pthread_cond_wait(&lu->cond, &lu->lock);
-
- pthread_cleanup_pop(true);
-}
-
-static void lookup_update(struct lookup * lu,
- kad_msg_t * msg)
-{
- struct list_head * p = NULL;
- struct list_head * h;
- struct contact * c = NULL;
- size_t n;
- size_t pos = 0;
- bool mod = false;
-
- assert(lu);
- assert(msg);
-
- if (dht_get_state() != DHT_RUNNING)
- return;
-
- pthread_mutex_lock(&lu->lock);
-
- list_for_each_safe(p, h, &lu->cookies) {
- struct cookie_el * e = list_entry(p, struct cookie_el, next);
- if (e->cookie == msg->cookie) {
- list_del(&e->next);
- free(e);
- break;
- }
- }
-
- if (lu->state == LU_COMPLETE) {
- pthread_mutex_unlock(&lu->lock);
- return;
- }
-
- if (msg->n_addrs > 0) {
- if (lu->addrs == NULL) {
- lu->addrs = malloc(sizeof(*lu->addrs) * msg->n_addrs);
- for (n = 0; n < msg->n_addrs; ++n)
- lu->addrs[n] = msg->addrs[n];
- lu->n_addrs = msg->n_addrs;
- }
-
- lu->state = LU_COMPLETE;
- pthread_cond_broadcast(&lu->cond);
- pthread_mutex_unlock(&lu->lock);
- return;
- }
-
- pthread_cleanup_push(__cleanup_mutex_unlock, &lu->lock);
-
- while (lu->state == LU_INIT) {
- pthread_rwlock_unlock(&dht.lock);
- pthread_cond_wait(&lu->cond, &lu->lock);
- pthread_rwlock_rdlock(&dht.lock);
- }
-
- pthread_cleanup_pop(false);
-
- for (n = 0; n < msg->n_contacts; ++n) {
- c = contact_create(msg->contacts[n]->id.data,
- dht.b, msg->contacts[n]->addr);
- if (c == NULL)
- continue;
-
- pos = 0;
-
- list_for_each(p, &lu->contacts) {
- struct contact * e;
- e = list_entry(p, struct contact, next);
- if (!memcmp(e->id, c->id, dht.b)) {
- contact_destroy(c);
- c = NULL;
- break;
- }
-
- if (dist(c->id, lu->key) > dist(e->id, lu->key))
- break;
-
- pos++;
- }
-
- if (c == NULL)
- continue;
-
- if (lu->n_contacts < dht.k) {
- list_add_tail(&c->next, p);
- ++lu->n_contacts;
- mod = true;
- } else if (pos == dht.k) {
- contact_destroy(c);
- } else {
- struct contact * d;
- list_add_tail(&c->next, p);
- d = list_last_entry(&lu->contacts,
- struct contact, next);
- list_del(&d->next);
- assert(lu->contacts.prv != &d->next);
- contact_destroy(d);
- mod = true;
- }
- }
-
- if (list_is_empty(&lu->cookies) && !mod)
- lu->state = LU_COMPLETE;
- else
- lu->state = LU_UPDATE;
-
- pthread_cond_broadcast(&lu->cond);
- pthread_mutex_unlock(&lu->lock);
- return;
-}
-
-static ssize_t lookup_get_addrs(struct lookup * lu,
- uint64_t * addrs)
-{
- ssize_t n;
-
- assert(lu);
-
- pthread_mutex_lock(&lu->lock);
-
- for (n = 0; (size_t) n < lu->n_addrs; ++n)
- addrs[n] = lu->addrs[n];
-
- assert((size_t) n == lu->n_addrs);
-
- pthread_mutex_unlock(&lu->lock);
-
- return n;
-}
-
-static ssize_t lookup_contact_addrs(struct lookup * lu,
- uint64_t * addrs)
-{
- struct list_head * p;
- ssize_t n = 0;
-
- assert(lu);
- assert(addrs);
-
- pthread_mutex_lock(&lu->lock);
-
- list_for_each(p, &lu->contacts) {
- struct contact * c = list_entry(p, struct contact, next);
- addrs[n] = c->addr;
- n++;
- }
-
- pthread_mutex_unlock(&lu->lock);
-
- return n;
-}
-
-static void lookup_new_addrs(struct lookup * lu,
- uint64_t * addrs)
-{
- struct list_head * p;
- size_t n = 0;
-
- assert(lu);
- assert(addrs);
-
- pthread_mutex_lock(&lu->lock);
-
- /* Uses fails to check if the contact has been contacted. */
- list_for_each(p, &lu->contacts) {
- struct contact * c = list_entry(p, struct contact, next);
- if (c->fails == 0) {
- c->fails = 1;
- addrs[n] = c->addr;
- n++;
- }
-
- if (n == KAD_ALPHA)
- break;
- }
-
- assert(n <= KAD_ALPHA);
-
- addrs[n] = 0;
-
- pthread_mutex_unlock(&lu->lock);
-}
-
-static void lookup_set_state(struct lookup * lu,
- enum lookup_state state)
-{
- pthread_mutex_lock(&lu->lock);
-
- lu->state = state;
- pthread_cond_broadcast(&lu->cond);
-
- pthread_mutex_unlock(&lu->lock);
-}
-
-static void cancel_lookup_wait(void * o)
-{
- struct lookup * lu = (struct lookup *) o;
- lu->state = LU_NULL;
- pthread_mutex_unlock(&lu->lock);
- lookup_destroy(lu);
-}
-
-static enum lookup_state lookup_wait(struct lookup * lu)
-{
- struct timespec timeo = {KAD_T_RESP, 0};
- struct timespec abs;
- enum lookup_state state;
- int ret = 0;
-
- clock_gettime(PTHREAD_COND_CLOCK, &abs);
-
- ts_add(&abs, &timeo, &abs);
-
- pthread_mutex_lock(&lu->lock);
-
- if (lu->state == LU_INIT || lu->state == LU_UPDATE)
- lu->state = LU_PENDING;
-
- pthread_cleanup_push(cancel_lookup_wait, lu);
-
- while (lu->state == LU_PENDING && ret != -ETIMEDOUT)
- ret = -pthread_cond_timedwait(&lu->cond, &lu->lock, &abs);
-
- pthread_cleanup_pop(false);
-
- if (ret == -ETIMEDOUT)
- lu->state = LU_COMPLETE;
-
- state = lu->state;
-
- pthread_mutex_unlock(&lu->lock);
-
- return state;
-}
-
-static struct kad_req * dht_find_request(kad_msg_t * msg)
-{
- struct list_head * p;
- assert(msg);
-
- list_for_each(p, &dht.requests) {
- struct kad_req * r = list_entry(p, struct kad_req, next);
- if (r->cookie == msg->cookie)
- return r;
- }
-
- return NULL;
-}
-
-static struct lookup * dht_find_lookup(uint32_t cookie)
-{
- struct list_head * p;
- struct list_head * p2;
- struct list_head * h2;
-
- assert(cookie > 0);
-
- list_for_each(p, &dht.lookups) {
- struct lookup * l = list_entry(p, struct lookup, next);
- pthread_mutex_lock(&l->lock);
- list_for_each_safe(p2, h2, &l->cookies) {
- struct cookie_el * e;
- e = list_entry(p2, struct cookie_el, next);
- if (e->cookie == cookie) {
- list_del(&e->next);
- free(e);
- pthread_mutex_unlock(&l->lock);
- return l;
- }
- }
- pthread_mutex_unlock(&l->lock);
- }
-
- return NULL;
-}
-
-static struct val * val_create(uint64_t addr,
- time_t exp)
-{
- struct val * v;
- struct timespec t;
-
- v = malloc(sizeof(*v));
- if (v == NULL)
- return NULL;
-
- list_head_init(&v->next);
- v->addr = addr;
-
- clock_gettime(CLOCK_REALTIME_COARSE, &t);
-
- v->t_exp = t.tv_sec + exp;
- v->t_rep = t.tv_sec + KAD_T_REPL;
-
- return v;
-}
-
-static void val_destroy(struct val * v)
-{
- assert(v);
-
- free(v);
-}
-
-static struct ref_entry * ref_entry_create(const uint8_t * key)
-{
- struct ref_entry * e;
- struct timespec t;
-
- assert(key);
-
- e = malloc(sizeof(*e));
- if (e == NULL)
- return NULL;
-
- e->key = dht_dup_key(key, dht.b);
- if (e->key == NULL) {
- free(e);
- return NULL;
- }
-
- clock_gettime(CLOCK_REALTIME_COARSE, &t);
-
- e->t_rep = t.tv_sec + dht.t_repub;
-
- return e;
-}
-
-static void ref_entry_destroy(struct ref_entry * e)
-{
- free(e->key);
- free(e);
-}
-
-static struct dht_entry * dht_entry_create(const uint8_t * key)
-{
- struct dht_entry * e;
-
- assert(key);
-
- e = malloc(sizeof(*e));
- if (e == NULL)
- return NULL;
-
- list_head_init(&e->next);
- list_head_init(&e->vals);
-
- e->n_vals = 0;
-
- e->key = dht_dup_key(key, dht.b);
- if (e->key == NULL) {
- free(e);
- return NULL;
- }
-
- return e;
-}
-
-static void dht_entry_destroy(struct dht_entry * e)
-{
- struct list_head * p;
- struct list_head * h;
-
- assert(e);
-
- list_for_each_safe(p, h, &e->vals) {
- struct val * v = list_entry(p, struct val, next);
- list_del(&v->next);
- val_destroy(v);
- }
-
- free(e->key);
-
- free(e);
-}
-
-static int dht_entry_add_addr(struct dht_entry * e,
- uint64_t addr,
- time_t exp)
-{
- struct list_head * p;
- struct val * val;
- struct timespec t;
-
- clock_gettime(CLOCK_REALTIME_COARSE, &t);
-
- list_for_each(p, &e->vals) {
- struct val * v = list_entry(p, struct val, next);
- if (v->addr == addr) {
- if (v->t_exp < t.tv_sec + exp) {
- v->t_exp = t.tv_sec + exp;
- v->t_rep = t.tv_sec + KAD_T_REPL;
- }
-
- return 0;
- }
- }
-
- val = val_create(addr, exp);
- if (val == NULL)
- return -ENOMEM;
-
- list_add(&val->next, &e->vals);
- ++e->n_vals;
-
- return 0;
-}
-
-
-static void dht_entry_del_addr(struct dht_entry * e,
- uint64_t addr)
-{
- struct list_head * p;
- struct list_head * h;
-
- assert(e);
-
- list_for_each_safe(p, h, &e->vals) {
- struct val * v = list_entry(p, struct val, next);
- if (v->addr == addr) {
- list_del(&v->next);
- val_destroy(v);
- --e->n_vals;
- }
- }
-
- if (e->n_vals == 0) {
- list_del(&e->next);
- dht_entry_destroy(e);
- }
-}
-
-static uint64_t dht_entry_get_addr(struct dht_entry * e)
-{
- struct list_head * p;
-
- assert(e);
- assert(!list_is_empty(&e->vals));
-
- list_for_each(p, &e->vals) {
- struct val * v = list_entry(p, struct val, next);
- if (v->addr != dht.addr)
- return v->addr;
- }
-
- return 0;
-}
-
-/* Forward declaration. */
-static struct lookup * kad_lookup(const uint8_t * key,
- enum kad_code code);
-
-
-/* Build a refresh list. */
-static void bucket_refresh(struct bucket * b,
- time_t t,
- struct list_head * r)
-{
- size_t i;
-
- if (*b->children != NULL)
- for (i = 0; i < (1L << KAD_BETA); ++i)
- bucket_refresh(b->children[i], t, r);
-
- if (b->n_contacts == 0)
- return;
-
- if (t > b->t_refr) {
- struct contact * c;
- struct contact * d;
- c = list_first_entry(&b->contacts, struct contact, next);
- d = contact_create(c->id, dht.b, c->addr);
- if (c != NULL)
- list_add(&d->next, r);
- return;
- }
-}
-
-
-static struct bucket * bucket_create(void)
-{
- struct bucket * b;
- struct timespec t;
- size_t i;
-
- b = malloc(sizeof(*b));
- if (b == NULL)
- return NULL;
-
- list_head_init(&b->contacts);
- b->n_contacts = 0;
-
- list_head_init(&b->alts);
- b->n_alts = 0;
-
- clock_gettime(CLOCK_REALTIME_COARSE, &t);
- b->t_refr = t.tv_sec + KAD_T_REFR;
-
- for (i = 0; i < (1L << KAD_BETA); ++i)
- b->children[i] = NULL;
-
- b->parent = NULL;
- b->depth = 0;
-
- return b;
-}
-
-static void bucket_destroy(struct bucket * b)
-{
- struct list_head * p;
- struct list_head * h;
- size_t i;
-
- assert(b);
-
- for (i = 0; i < (1L << KAD_BETA); ++i)
- if (b->children[i] != NULL)
- bucket_destroy(b->children[i]);
-
- list_for_each_safe(p, h, &b->contacts) {
- struct contact * c = list_entry(p, struct contact, next);
- list_del(&c->next);
- contact_destroy(c);
- --b->n_contacts;
- }
-
- list_for_each_safe(p, h, &b->alts) {
- struct contact * c = list_entry(p, struct contact, next);
- list_del(&c->next);
- contact_destroy(c);
- --b->n_contacts;
- }
-
- free(b);
-}
-
-static bool bucket_has_id(struct bucket * b,
- const uint8_t * id)
-{
- uint8_t mask;
- uint8_t byte;
-
- if (b->depth == 0)
- return true;
-
- byte = id[(b->depth * KAD_BETA) / CHAR_BIT];
-
- mask = ((1L << KAD_BETA) - 1) & 0xFF;
-
- byte >>= (CHAR_BIT - KAD_BETA) -
- (((b->depth - 1) * KAD_BETA) & (CHAR_BIT - 1));
-
- return ((byte & mask) == b->mask);
-}
-
-static int split_bucket(struct bucket * b)
-{
- struct list_head * p;
- struct list_head * h;
- uint8_t mask = 0;
- size_t i;
- size_t c;
-
- assert(b);
- assert(b->n_alts == 0);
- assert(b->n_contacts);
- assert(b->children[0] == NULL);
-
- c = b->n_contacts;
-
- for (i = 0; i < (1L << KAD_BETA); ++i) {
- b->children[i] = bucket_create();
- if (b->children[i] == NULL) {
- size_t j;
- for (j = 0; j < i; ++j)
- bucket_destroy(b->children[j]);
- return -1;
- }
-
- b->children[i]->depth = b->depth + 1;
- b->children[i]->mask = mask;
- b->children[i]->parent = b;
-
- list_for_each_safe(p, h, &b->contacts) {
- struct contact * c;
- c = list_entry(p, struct contact, next);
- if (bucket_has_id(b->children[i], c->id)) {
- list_del(&c->next);
- --b->n_contacts;
- list_add(&c->next, &b->children[i]->contacts);
- ++b->children[i]->n_contacts;
- }
- }
-
- mask++;
- }
-
- for (i = 0; i < (1L << KAD_BETA); ++i)
- if (b->children[i]->n_contacts == c)
- split_bucket(b->children[i]);
-
- return 0;
-}
-
-/* Locked externally to mandate update as (final) part of join transaction. */
-static int dht_update_bucket(const uint8_t * id,
- uint64_t addr)
-{
- struct list_head * p;
- struct list_head * h;
- struct bucket * b;
- struct contact * c;
-
- b = dht_get_bucket(id);
- if (b == NULL)
- return -1;
-
- c = contact_create(id, dht.b, addr);
- if (c == NULL)
- return -1;
-
- list_for_each_safe(p, h, &b->contacts) {
- struct contact * d = list_entry(p, struct contact, next);
- if (d->addr == addr) {
- list_del(&d->next);
- contact_destroy(d);
- --b->n_contacts;
- }
- }
-
- if (b->n_contacts == dht.k) {
- if (bucket_has_id(b, dht.id)) {
- list_add_tail(&c->next, &b->contacts);
- ++b->n_contacts;
- if (split_bucket(b)) {
- list_del(&c->next);
- contact_destroy(c);
- --b->n_contacts;
- }
- } else if (b->n_alts == dht.k) {
- struct contact * d;
- d = list_first_entry(&b->alts, struct contact, next);
- list_del(&d->next);
- contact_destroy(d);
- list_add_tail(&c->next, &b->alts);
- } else {
- list_add_tail(&c->next, &b->alts);
- ++b->n_alts;
- }
- } else {
- list_add_tail(&c->next, &b->contacts);
- ++b->n_contacts;
- }
-
- return 0;
-}
-
-static int send_msg(kad_msg_t * msg,
- uint64_t addr)
-{
-#ifndef __DHT_TEST__
- struct shm_du_buff * sdb;
- size_t len;
-#endif
- int retr = 0;
-
- if (msg->code == KAD_RESPONSE)
- retr = KAD_RESP_RETR;
-
- pthread_rwlock_wrlock(&dht.lock);
-
- if (dht.id != NULL) {
- msg->has_s_id = true;
- msg->s_id.data = dht.id;
- msg->s_id.len = dht.b;
- }
-
- msg->s_addr = dht.addr;
-
- if (msg->code < KAD_STORE) {
- msg->cookie = bmp_allocate(dht.cookies);
- if (!bmp_is_id_valid(dht.cookies, msg->cookie)) {
- pthread_rwlock_unlock(&dht.lock);
- goto fail_bmp_alloc;
- }
- }
-
- pthread_rwlock_unlock(&dht.lock);
-
-#ifndef __DHT_TEST__
- len = kad_msg__get_packed_size(msg);
- if (len == 0)
- goto fail_msg;
-
- while (true) {
- if (ipcp_sdb_reserve(&sdb, len))
- goto fail_msg;
-
- kad_msg__pack(msg, shm_du_buff_head(sdb));
-
- if (dt_write_packet(addr, QOS_CUBE_BE, dht.eid, sdb) == 0)
- break;
-
- ipcp_sdb_release(sdb);
-
- sleep(1);
-
- if (--retr < 0)
- goto fail_msg;
- }
-
-#else
- (void) addr;
- (void) retr;
-#endif /* __DHT_TEST__ */
-
- if (msg->code < KAD_STORE && dht_get_state() != DHT_SHUTDOWN)
- kad_req_create(msg, addr);
-
- return msg->cookie;
-#ifndef __DHT_TEST__
- fail_msg:
- pthread_rwlock_wrlock(&dht.lock);
- bmp_release(dht.cookies, msg->cookie);
- pthread_rwlock_unlock(&dht.lock);
-#endif /* !__DHT_TEST__ */
- fail_bmp_alloc:
- return -1;
-}
-
-static struct dht_entry * dht_find_entry(const uint8_t * key)
-{
- struct list_head * p;
-
- list_for_each(p, &dht.entries) {
- struct dht_entry * e = list_entry(p, struct dht_entry, next);
- if (!memcmp(key, e->key, dht.b))
- return e;
- }
-
- return NULL;
-}
-
-static int kad_add(const kad_contact_msg_t * contacts,
- ssize_t n,
- time_t exp)
-{
- struct dht_entry * e;
-
- pthread_rwlock_wrlock(&dht.lock);
-
- while (n-- > 0) {
- if (contacts[n].id.len != dht.b)
- log_warn("Bad key length in contact data.");
-
- e = dht_find_entry(contacts[n].id.data);
- if (e != NULL) {
- if (dht_entry_add_addr(e, contacts[n].addr, exp))
- goto fail;
- } else {
- e = dht_entry_create(contacts[n].id.data);
- if (e == NULL)
- goto fail;
-
- if (dht_entry_add_addr(e, contacts[n].addr, exp)) {
- dht_entry_destroy(e);
- goto fail;
- }
-
- list_add(&e->next, &dht.entries);
- }
- }
-
- pthread_rwlock_unlock(&dht.lock);
- return 0;
-
- fail:
- pthread_rwlock_unlock(&dht.lock);
- return -ENOMEM;
-}
-
-static int wait_resp(kad_msg_t * msg,
- time_t timeo)
-{
- struct kad_req * req;
-
- assert(msg);
-
- pthread_rwlock_rdlock(&dht.lock);
-
- req = dht_find_request(msg);
- if (req == NULL) {
- pthread_rwlock_unlock(&dht.lock);
- return -EPERM;
- }
-
- pthread_rwlock_unlock(&dht.lock);
-
- return kad_req_wait(req, timeo);
-}
-
-static int kad_store(const uint8_t * key,
- uint64_t addr,
- uint64_t r_addr,
- time_t ttl)
-{
- kad_msg_t msg = KAD_MSG__INIT;
- kad_contact_msg_t cmsg = KAD_CONTACT_MSG__INIT;
- kad_contact_msg_t * cmsgp[1];
-
- cmsg.id.data = (uint8_t *) key;
- cmsg.addr = addr;
-
- pthread_rwlock_rdlock(&dht.lock);
-
- cmsg.id.len = dht.b;
-
- pthread_rwlock_unlock(&dht.lock);
-
- cmsgp[0] = &cmsg;
-
- msg.code = KAD_STORE;
- msg.has_t_expire = true;
- msg.t_expire = ttl;
- msg.n_contacts = 1;
- msg.contacts = cmsgp;
-
- if (send_msg(&msg, r_addr) < 0)
- return -1;
-
- return 0;
-}
-
-static ssize_t kad_find(struct lookup * lu,
- const uint64_t * addrs,
- enum kad_code code)
-{
- kad_msg_t msg = KAD_MSG__INIT;
- ssize_t sent = 0;
-
- assert(lu->key);
-
- msg.code = code;
-
- msg.has_key = true;
- msg.key.data = (uint8_t *) lu->key;
- msg.key.len = dht.b;
-
- while (*addrs != 0) {
- struct cookie_el * c;
- int ret;
-
- if (*addrs == dht.addr) {
- ++addrs;
- continue;
- }
-
- ret = send_msg(&msg, *addrs);
- if (ret < 0)
- break;
-
- c = malloc(sizeof(*c));
- if (c == NULL)
- break;
-
- c->cookie = (uint32_t) ret;
-
- pthread_mutex_lock(&lu->lock);
-
- list_add_tail(&c->next, &lu->cookies);
-
- pthread_mutex_unlock(&lu->lock);
-
- ++sent;
- ++addrs;
- }
-
- return sent;
-}
-
-static void lookup_detach(struct lookup * lu)
-{
- pthread_rwlock_wrlock(&dht.lock);
-
- list_del(&lu->next);
-
- pthread_rwlock_unlock(&dht.lock);
-}
-
-static struct lookup * kad_lookup( const uint8_t * id,
- enum kad_code code)
-{
- uint64_t addrs[KAD_ALPHA + 1];
- enum lookup_state state;
- struct lookup * lu;
-
- lu = lookup_create(id);
- if (lu == NULL)
- return NULL;
-
- lookup_new_addrs(lu, addrs);
-
- if (addrs[0] == 0) {
- lookup_detach(lu);
- lookup_destroy(lu);
- return NULL;
- }
-
- if (kad_find(lu, addrs, code) == 0) {
- lookup_detach(lu);
- return lu;
- }
-
- while ((state = lookup_wait(lu)) != LU_COMPLETE) {
- switch (state) {
- case LU_UPDATE:
- lookup_new_addrs(lu, addrs);
- if (addrs[0] == 0)
- break;
-
- kad_find(lu, addrs, code);
- break;
- case LU_DESTROY:
- lookup_detach(lu);
- lookup_set_state(lu, LU_NULL);
- return NULL;
- default:
- break;
- }
- }
-
- assert(state == LU_COMPLETE);
-
- lookup_detach(lu);
-
- return lu;
-}
-
-static void kad_publish(const uint8_t * key,
- uint64_t addr,
- time_t exp)
-{
- struct lookup * lu;
- uint64_t * addrs;
- ssize_t n;
- size_t k;
- time_t t_expire;
-
-
- assert(key);
-
- pthread_rwlock_rdlock(&dht.lock);
-
- k = dht.k;
- t_expire = dht.t_expire;
-
- pthread_rwlock_unlock(&dht.lock);
-
- addrs = malloc(k * sizeof(*addrs));
- if (addrs == NULL)
- return;
-
- lu = kad_lookup(key, KAD_FIND_NODE);
- if (lu == NULL) {
- free(addrs);
- return;
- }
-
- n = lookup_contact_addrs(lu, addrs);
-
- while (n-- > 0) {
- if (addrs[n] == dht.addr) {
- kad_contact_msg_t msg = KAD_CONTACT_MSG__INIT;
- msg.id.data = (uint8_t *) key;
- msg.id.len = dht.b;
- msg.addr = addr;
- kad_add(&msg, 1, exp);
- } else {
- if (kad_store(key, addr, addrs[n], t_expire))
- log_warn("Failed to send store message.");
- }
- }
-
- lookup_destroy(lu);
-
- free(addrs);
-}
-
-static int kad_join(uint64_t addr)
-{
- kad_msg_t msg = KAD_MSG__INIT;
-
- msg.code = KAD_JOIN;
-
- msg.has_alpha = true;
- msg.has_b = true;
- msg.has_k = true;
- msg.has_t_refresh = true;
- msg.has_t_replicate = true;
- msg.alpha = KAD_ALPHA;
- msg.k = KAD_K;
- msg.t_refresh = KAD_T_REFR;
- msg.t_replicate = KAD_T_REPL;
-
- pthread_rwlock_rdlock(&dht.lock);
-
- msg.b = dht.b;
-
- pthread_rwlock_unlock(&dht.lock);
-
- if (send_msg(&msg, addr) < 0)
- return -1;
-
- if (wait_resp(&msg, KAD_T_JOIN) < 0)
- return -1;
-
- dht.id = create_id(dht.b);
- if (dht.id == NULL)
- return -1;
-
- pthread_rwlock_wrlock(&dht.lock);
-
- dht_update_bucket(dht.id, dht.addr);
-
- pthread_rwlock_unlock(&dht.lock);
-
- return 0;
-}
-
-static void dht_dead_peer(uint8_t * key,
- uint64_t addr)
-{
- struct list_head * p;
- struct list_head * h;
- struct bucket * b;
-
- b = dht_get_bucket(key);
-
- list_for_each_safe(p, h, &b->contacts) {
- struct contact * c = list_entry(p, struct contact, next);
- if (b->n_contacts + b->n_alts <= dht.k) {
- ++c->fails;
- return;
- }
-
- if (c->addr == addr) {
- list_del(&c->next);
- contact_destroy(c);
- --b->n_contacts;
- break;
- }
- }
-
- while (b->n_contacts < dht.k && b->n_alts > 0) {
- struct contact * c;
- c = list_first_entry(&b->alts, struct contact, next);
- list_del(&c->next);
- --b->n_alts;
- list_add(&c->next, &b->contacts);
- ++b->n_contacts;
- }
-}
-
-static int dht_del(const uint8_t * key,
- uint64_t addr)
-{
- struct dht_entry * e;
-
- pthread_rwlock_wrlock(&dht.lock);
-
- e = dht_find_entry(key);
- if (e == NULL) {
- pthread_rwlock_unlock(&dht.lock);
- return -EPERM;
- }
-
- dht_entry_del_addr(e, addr);
-
- pthread_rwlock_unlock(&dht.lock);
-
- return 0;
-}
-
-static buffer_t dht_retrieve(const uint8_t * key)
-{
- struct dht_entry * e;
- struct list_head * p;
- buffer_t buf;
- uint64_t * pos;
- size_t addrs = 0;
-
- pthread_rwlock_rdlock(&dht.lock);
-
- e = dht_find_entry(key);
- if (e == NULL)
- goto fail;
-
- buf.len = MIN(DHT_RETR_ADDR, e->n_vals);
- if (buf.len == 0)
- goto fail;
-
- pos = malloc(sizeof(dht.addr) * buf.len);
- if (pos == NULL)
- goto fail;
-
- buf.data = (uint8_t *) pos;
-
- list_for_each(p, &e->vals) {
- struct val * v = list_entry(p, struct val, next);
- *pos++ = v->addr;
- if (++addrs >= buf.len)
- break;
- }
-
- pthread_rwlock_unlock(&dht.lock);
-
- return buf;
-
- fail:
- pthread_rwlock_unlock(&dht.lock);
- buf.len = 0;
-
- return buf;
-}
-
-static ssize_t dht_get_contacts(const uint8_t * key,
- kad_contact_msg_t *** msgs)
-{
- struct list_head l;
- struct list_head * p;
- struct list_head * h;
- size_t len;
- size_t i = 0;
-
- list_head_init(&l);
-
- pthread_rwlock_wrlock(&dht.lock);
-
- len = dht_contact_list(&l, key);
- if (len == 0) {
- pthread_rwlock_unlock(&dht.lock);
- *msgs = NULL;
- return 0;
- }
-
- *msgs = malloc(len * sizeof(**msgs));
- if (*msgs == NULL) {
- pthread_rwlock_unlock(&dht.lock);
- return 0;
- }
-
- list_for_each_safe(p, h, &l) {
- struct contact * c = list_entry(p, struct contact, next);
- (*msgs)[i] = malloc(sizeof(***msgs));
- if ((*msgs)[i] == NULL) {
- pthread_rwlock_unlock(&dht.lock);
- while (i > 0)
- free(*msgs[--i]);
- free(*msgs);
- *msgs = NULL;
- return 0;
- }
-
- kad_contact_msg__init((*msgs)[i]);
-
- (*msgs)[i]->id.data = c->id;
- (*msgs)[i]->id.len = dht.b;
- (*msgs)[i++]->addr = c->addr;
- list_del(&c->next);
- free(c);
- }
-
- pthread_rwlock_unlock(&dht.lock);
-
- return i;
-}
-
-static time_t gcd(time_t a,
- time_t b)
-{
- if (a == 0)
- return b;
-
- return gcd(b % a, a);
-}
-
-static void * work(void * o)
-{
- struct timespec now;
- struct list_head * p;
- struct list_head * h;
- struct list_head reflist;
- time_t intv;
- struct lookup * lu;
-
- (void) o;
-
- pthread_rwlock_rdlock(&dht.lock);
-
- intv = gcd(dht.t_expire, dht.t_repub);
- intv = gcd(intv, gcd(KAD_T_REPL, KAD_T_REFR)) / 2;
-
- pthread_rwlock_unlock(&dht.lock);
-
- list_head_init(&reflist);
-
- while (true) {
- clock_gettime(CLOCK_REALTIME_COARSE, &now);
-
- pthread_rwlock_wrlock(&dht.lock);
-
- /* Republish registered hashes. */
- list_for_each(p, &dht.refs) {
- struct ref_entry * e;
- uint8_t * key;
- uint64_t addr;
- time_t t_expire;
- e = list_entry(p, struct ref_entry, next);
- if (now.tv_sec > e->t_rep) {
- key = dht_dup_key(e->key, dht.b);
- if (key == NULL)
- continue;
- addr = dht.addr;
- t_expire = dht.t_expire;
- e->t_rep = now.tv_sec + dht.t_repub;
-
- pthread_rwlock_unlock(&dht.lock);
- kad_publish(key, addr, t_expire);
- pthread_rwlock_wrlock(&dht.lock);
- free(key);
- }
- }
-
- /* Remove stale entries and republish if necessary. */
- list_for_each_safe(p, h, &dht.entries) {
- struct list_head * p1;
- struct list_head * h1;
- struct dht_entry * e;
- uint8_t * key;
- time_t t_expire;
- e = list_entry (p, struct dht_entry, next);
- list_for_each_safe(p1, h1, &e->vals) {
- struct val * v;
- uint64_t addr;
- v = list_entry(p1, struct val, next);
- if (now.tv_sec > v->t_exp) {
- list_del(&v->next);
- val_destroy(v);
- continue;
- }
-
- if (now.tv_sec > v->t_rep) {
- key = dht_dup_key(e->key, dht.b);
- addr = v->addr;
- t_expire = dht.t_expire = now.tv_sec;
- v->t_rep = now.tv_sec + dht.t_replic;
- pthread_rwlock_unlock(&dht.lock);
- kad_publish(key, addr, t_expire);
- pthread_rwlock_wrlock(&dht.lock);
- free(key);
- }
- }
- }
-
- /* Check the requests list for unresponsive nodes. */
- list_for_each_safe(p, h, &dht.requests) {
- struct kad_req * r;
- r = list_entry(p, struct kad_req, next);
- if (now.tv_sec > r->t_exp) {
- list_del(&r->next);
- bmp_release(dht.cookies, r->cookie);
- dht_dead_peer(r->key, r->addr);
- kad_req_destroy(r);
- }
- }
-
- /* Refresh unaccessed buckets. */
- bucket_refresh(dht.buckets, now.tv_sec, &reflist);
-
- pthread_rwlock_unlock(&dht.lock);
-
- list_for_each_safe(p, h, &reflist) {
- struct contact * c;
- c = list_entry(p, struct contact, next);
- lu = kad_lookup(c->id, KAD_FIND_NODE);
- if (lu != NULL)
- lookup_destroy(lu);
- list_del(&c->next);
- contact_destroy(c);
- }
-
- sleep(intv);
- }
-
- return (void *) 0;
-}
-
-static int kad_handle_join_resp(struct kad_req * req,
- kad_msg_t * msg)
-{
- assert(req);
- assert(msg);
-
- /* We might send version numbers later to warn of updates if needed. */
- if (!(msg->has_alpha && msg->has_b && msg->has_k && msg->has_t_expire &&
- msg->has_t_refresh && msg->has_t_replicate)) {
- log_warn("Join refused by remote.");
- return -1;
- }
-
- if (msg->b < sizeof(uint64_t)) {
- log_err("Hash sizes less than 8 bytes unsupported.");
- return -1;
- }
-
- pthread_rwlock_wrlock(&dht.lock);
-
- dht.buckets = bucket_create();
- if (dht.buckets == NULL) {
- pthread_rwlock_unlock(&dht.lock);
- return -1;
- }
-
- /* Likely corrupt packet. The member will refuse, we might here too. */
- if (msg->alpha != KAD_ALPHA || msg->k != KAD_K)
- log_warn("Different kademlia parameters detected.");
-
- if (msg->t_replicate != KAD_T_REPL)
- log_warn("Different kademlia replication time detected.");
-
- if (msg->t_refresh != KAD_T_REFR)
- log_warn("Different kademlia refresh time detected.");
-
- dht.k = msg->k;
- dht.b = msg->b;
- dht.t_expire = msg->t_expire;
- dht.t_repub = MAX(1, dht.t_expire - 10);
-
- if (pthread_create(&dht.worker, NULL, work, NULL)) {
- bucket_destroy(dht.buckets);
- pthread_rwlock_unlock(&dht.lock);
- return -1;
- }
-
- kad_req_respond(req);
-
- dht_update_bucket(msg->s_id.data, msg->s_addr);
-
- pthread_rwlock_unlock(&dht.lock);
-
- log_dbg("Enrollment of DHT completed.");
-
- return 0;
-}
-
-static int kad_handle_find_resp(struct kad_req * req,
- kad_msg_t * msg)
-{
- struct lookup * lu;
-
- assert(req);
- assert(msg);
-
- pthread_rwlock_rdlock(&dht.lock);
-
- lu = dht_find_lookup(req->cookie);
- if (lu == NULL) {
- pthread_rwlock_unlock(&dht.lock);
- return -1;
- }
-
- lookup_update(lu, msg);
-
- pthread_rwlock_unlock(&dht.lock);
-
- return 0;
-}
-
-static void kad_handle_response(kad_msg_t * msg)
-{
- struct kad_req * req;
-
- assert(msg);
-
- pthread_rwlock_wrlock(&dht.lock);
-
- req = dht_find_request(msg);
- if (req == NULL) {
- pthread_rwlock_unlock(&dht.lock);
- return;
- }
-
- bmp_release(dht.cookies, req->cookie);
- list_del(&req->next);
-
- pthread_rwlock_unlock(&dht.lock);
-
- switch(req->code) {
- case KAD_JOIN:
- if (kad_handle_join_resp(req, msg))
- log_err("Enrollment of DHT failed.");
- break;
- case KAD_FIND_VALUE:
- case KAD_FIND_NODE:
- if (dht_get_state() != DHT_RUNNING)
- break;
- kad_handle_find_resp(req, msg);
- break;
- default:
- break;
- }
-
- kad_req_destroy(req);
-}
-
-int dht_bootstrap()
-{
- pthread_rwlock_wrlock(&dht.lock);
-
-#ifndef __DHT_TEST__
- dht.b = hash_len(ipcpi.dir_hash_algo);
-#else
- dht.b = DHT_TEST_KEY_LEN;
-#endif
- dht.t_expire = 86400; /* 1 day */
- dht.t_repub = dht.t_expire - 10;
- dht.k = KAD_K;
-
- dht.id = create_id(dht.b);
- if (dht.id == NULL)
- goto fail_id;
-
- dht.buckets = bucket_create();
- if (dht.buckets == NULL)
- goto fail_buckets;
-
- dht.buckets->depth = 0;
- dht.buckets->mask = 0;
-
- if (pthread_create(&dht.worker, NULL, work, NULL))
- goto fail_pthread_create;
-
- dht.state = DHT_RUNNING;
-
- dht_update_bucket(dht.id, dht.addr);
-
- pthread_rwlock_unlock(&dht.lock);
-
- return 0;
-
- fail_pthread_create:
- bucket_destroy(dht.buckets);
- dht.buckets = NULL;
- fail_buckets:
- free(dht.id);
- dht.id = NULL;
- fail_id:
- pthread_rwlock_unlock(&dht.lock);
- return -1;
-}
-
-static struct ref_entry * ref_entry_get(const uint8_t * key)
-{
- struct list_head * p;
-
- list_for_each(p, &dht.refs) {
- struct ref_entry * r = list_entry(p, struct ref_entry, next);
- if (!memcmp(key, r->key, dht. b) )
- return r;
- }
-
- return NULL;
-}
-
-int dht_reg(const uint8_t * key)
-{
- struct ref_entry * e;
- uint64_t addr;
- time_t t_expire;
-
- assert(key);
- assert(dht.addr != 0);
-
- if (dht_wait_running())
- return -1;
-
- pthread_rwlock_wrlock(&dht.lock);
-
- if (ref_entry_get(key) != NULL) {
- log_dbg("Name already registered.");
- pthread_rwlock_unlock(&dht.lock);
- return 0;
- }
-
- e = ref_entry_create(key);
- if (e == NULL) {
- pthread_rwlock_unlock(&dht.lock);
- return -ENOMEM;
- }
-
- list_add(&e->next, &dht.refs);
-
- t_expire = dht.t_expire;
- addr = dht.addr;
-
- pthread_rwlock_unlock(&dht.lock);
-
- kad_publish(key, addr, t_expire);
-
- return 0;
-}
-
-int dht_unreg(const uint8_t * key)
-{
- struct list_head * p;
- struct list_head * h;
-
- assert(key);
-
- if (dht_get_state() != DHT_RUNNING)
- return -1;
-
- pthread_rwlock_wrlock(&dht.lock);
-
- list_for_each_safe(p, h, &dht.refs) {
- struct ref_entry * r = list_entry(p, struct ref_entry, next);
- if (!memcmp(key, r->key, dht. b) ) {
- list_del(&r->next);
- ref_entry_destroy(r);
- }
- }
-
- dht_del(key, dht.addr);
-
- pthread_rwlock_unlock(&dht.lock);
-
- return 0;
-}
-
-uint64_t dht_query(const uint8_t * key)
-{
- struct dht_entry * e;
- struct lookup * lu;
- uint64_t addrs[KAD_K];
- size_t n;
-
- addrs[0] = 0;
-
- if (dht_wait_running())
- return 0;
-
- pthread_rwlock_rdlock(&dht.lock);
-
- e = dht_find_entry(key);
- if (e != NULL)
- addrs[0] = dht_entry_get_addr(e);
-
- pthread_rwlock_unlock(&dht.lock);
-
- if (addrs[0] != 0)
- return addrs[0];
-
- lu = kad_lookup(key, KAD_FIND_VALUE);
- if (lu == NULL)
- return 0;
-
- n = lookup_get_addrs(lu, addrs);
- if (n == 0) {
- lookup_destroy(lu);
- return 0;
- }
-
- lookup_destroy(lu);
-
- /* Current behaviour is anycast and return the first peer address. */
- if (addrs[0] != dht.addr)
- return addrs[0];
-
- if (n > 1)
- return addrs[1];
-
- return 0;
-}
-
-static void * dht_handle_packet(void * o)
-{
- (void) o;
-
- while (true) {
- kad_msg_t * msg;
- kad_contact_msg_t ** cmsgs;
- kad_msg_t resp_msg = KAD_MSG__INIT;
- uint64_t addr;
- buffer_t buf;
- size_t i;
- size_t b;
- size_t t_expire;
- struct cmd * cmd;
-
- pthread_mutex_lock(&dht.mtx);
-
- pthread_cleanup_push(__cleanup_mutex_unlock, &dht.mtx);
-
- while (list_is_empty(&dht.cmds))
- pthread_cond_wait(&dht.cond, &dht.mtx);
-
- cmd = list_last_entry(&dht.cmds, struct cmd, next);
- list_del(&cmd->next);
-
- pthread_cleanup_pop(true);
-
- i = shm_du_buff_tail(cmd->sdb) - shm_du_buff_head(cmd->sdb);
-
- msg = kad_msg__unpack(NULL, i, shm_du_buff_head(cmd->sdb));
-#ifndef __DHT_TEST__
- ipcp_sdb_release(cmd->sdb);
-#endif
- free(cmd);
-
- if (msg == NULL) {
- log_err("Failed to unpack message.");
- continue;
- }
-
- if (msg->code != KAD_RESPONSE && dht_wait_running()) {
- kad_msg__free_unpacked(msg, NULL);
- log_dbg("Got a request message when not running.");
- continue;
- }
-
- pthread_rwlock_rdlock(&dht.lock);
-
- b = dht.b;
- t_expire = dht.t_expire;
-
- pthread_rwlock_unlock(&dht.lock);
-
- if (msg->has_key && msg->key.len != b) {
- kad_msg__free_unpacked(msg, NULL);
- log_warn("Bad key in message.");
- continue;
- }
-
- if (msg->has_s_id && !msg->has_b && msg->s_id.len != b) {
- kad_msg__free_unpacked(msg, NULL);
- log_warn("Bad source ID in message of type %d.",
- msg->code);
- continue;
- }
-
- tpm_dec(dht.tpm);
-
- addr = msg->s_addr;
-
- resp_msg.code = KAD_RESPONSE;
- resp_msg.cookie = msg->cookie;
-
- switch(msg->code) {
- case KAD_JOIN:
- /* Refuse enrollee on check fails. */
- if (msg->alpha != KAD_ALPHA || msg->k != KAD_K) {
- log_warn("Parameter mismatch. "
- "DHT enrolment refused.");
- break;
- }
-
- if (msg->t_replicate != KAD_T_REPL) {
- log_warn("Replication time mismatch. "
- "DHT enrolment refused.");
-
- break;
- }
-
- if (msg->t_refresh != KAD_T_REFR) {
- log_warn("Refresh time mismatch. "
- "DHT enrolment refused.");
- break;
- }
-
- resp_msg.has_alpha = true;
- resp_msg.has_b = true;
- resp_msg.has_k = true;
- resp_msg.has_t_expire = true;
- resp_msg.has_t_refresh = true;
- resp_msg.has_t_replicate = true;
- resp_msg.alpha = KAD_ALPHA;
- resp_msg.b = b;
- resp_msg.k = KAD_K;
- resp_msg.t_expire = t_expire;
- resp_msg.t_refresh = KAD_T_REFR;
- resp_msg.t_replicate = KAD_T_REPL;
- break;
- case KAD_FIND_VALUE:
- buf = dht_retrieve(msg->key.data);
- if (buf.len != 0) {
- resp_msg.n_addrs = buf.len;
- resp_msg.addrs = (uint64_t *) buf.data;
- break;
- }
- /* FALLTHRU */
- case KAD_FIND_NODE:
- /* Return k closest contacts. */
- resp_msg.n_contacts =
- dht_get_contacts(msg->key.data, &cmsgs);
- resp_msg.contacts = cmsgs;
- break;
- case KAD_STORE:
- if (msg->n_contacts < 1) {
- log_warn("No contacts in store message.");
- break;
- }
-
- if (!msg->has_t_expire) {
- log_warn("No expiry time in store message.");
- break;
- }
-
- kad_add(*msg->contacts, msg->n_contacts,
- msg->t_expire);
- break;
- case KAD_RESPONSE:
- kad_handle_response(msg);
- break;
- default:
- assert(false);
- break;
- }
-
- if (msg->code != KAD_JOIN) {
- pthread_rwlock_wrlock(&dht.lock);
- if (dht_get_state() == DHT_JOINING &&
- dht.buckets == NULL) {
- pthread_rwlock_unlock(&dht.lock);
- goto finish;
- }
-
- if (dht_update_bucket(msg->s_id.data, addr))
- log_warn("Failed to update bucket.");
- pthread_rwlock_unlock(&dht.lock);
- }
-
- if (msg->code < KAD_STORE && send_msg(&resp_msg, addr) < 0)
- log_warn("Failed to send response.");
-
- finish:
- kad_msg__free_unpacked(msg, NULL);
-
- if (resp_msg.n_addrs > 0)
- free(resp_msg.addrs);
-
- if (resp_msg.n_contacts == 0) {
- tpm_inc(dht.tpm);
- continue;
- }
-
- for (i = 0; i < resp_msg.n_contacts; ++i)
- kad_contact_msg__free_unpacked(resp_msg.contacts[i],
- NULL);
- free(resp_msg.contacts);
-
- tpm_inc(dht.tpm);
- }
-
- return (void *) 0;
-}
-
-static void dht_post_packet(void * o,
- struct shm_du_buff * sdb)
-{
- struct cmd * cmd;
-
- (void) o;
-
- assert(o == &dht);
-
- if (dht_get_state() == DHT_SHUTDOWN) {
-#ifndef __DHT_TEST__
- ipcp_sdb_release(sdb);
-#endif
- return;
- }
-
- cmd = malloc(sizeof(*cmd));
- if (cmd == NULL) {
- log_err("Command failed. Out of memory.");
- return;
- }
-
- cmd->sdb = sdb;
-
- pthread_mutex_lock(&dht.mtx);
-
- list_add(&cmd->next, &dht.cmds);
-
- pthread_cond_signal(&dht.cond);
-
- pthread_mutex_unlock(&dht.mtx);
-}
-
-void dht_fini()
-{
- struct list_head * p;
- struct list_head * h;
-
-#ifndef __DHT_TEST__
- tpm_stop(dht.tpm);
-
- tpm_destroy(dht.tpm);
-#endif
- if (dht_get_state() == DHT_RUNNING) {
- dht_set_state(DHT_SHUTDOWN);
- pthread_cancel(dht.worker);
- pthread_join(dht.worker, NULL);
- }
-
- pthread_rwlock_wrlock(&dht.lock);
-
- list_for_each_safe(p, h, &dht.cmds) {
- struct cmd * c = list_entry(p, struct cmd, next);
- list_del(&c->next);
-#ifndef __DHT_TEST__
- ipcp_sdb_release(c->sdb);
-#endif
- free(c);
- }
-
- list_for_each_safe(p, h, &dht.entries) {
- struct dht_entry * e = list_entry(p, struct dht_entry, next);
- list_del(&e->next);
- dht_entry_destroy(e);
- }
-
- list_for_each_safe(p, h, &dht.requests) {
- struct kad_req * r = list_entry(p, struct kad_req, next);
- list_del(&r->next);
- kad_req_destroy(r);
- }
-
- list_for_each_safe(p, h, &dht.refs) {
- struct ref_entry * e = list_entry(p, struct ref_entry, next);
- list_del(&e->next);
- ref_entry_destroy(e);
- }
-
- list_for_each_safe(p, h, &dht.lookups) {
- struct lookup * l = list_entry(p, struct lookup, next);
- list_del(&l->next);
- lookup_destroy(l);
- }
-
- pthread_rwlock_unlock(&dht.lock);
-
- if (dht.buckets != NULL)
- bucket_destroy(dht.buckets);
-
- bmp_destroy(dht.cookies);
-
- pthread_mutex_destroy(&dht.mtx);
-
- pthread_rwlock_destroy(&dht.lock);
-
- free(dht.id);
-}
-
-static void * join_thr(void * o)
-{
- struct join_info * info = (struct join_info *) o;
- struct lookup * lu;
- size_t retr = 0;
-
- assert(info);
-
- while (kad_join(info->addr)) {
- if (dht_get_state() == DHT_SHUTDOWN) {
- log_dbg("DHT enrollment aborted.");
- goto finish;
- }
-
- if (retr++ == KAD_JOIN_RETR) {
- dht_set_state(DHT_INIT);
- log_warn("DHT enrollment attempt failed.");
- goto finish;
- }
-
- sleep(KAD_JOIN_INTV);
- }
-
- dht_set_state(DHT_RUNNING);
-
- lu = kad_lookup(dht.id, KAD_FIND_NODE);
- if (lu != NULL)
- lookup_destroy(lu);
-
- finish:
- free(info);
-
- return (void *) 0;
-}
-
-static void handle_event(void * self,
- int event,
- const void * o)
-{
- (void) self;
-
- if (event == NOTIFY_DT_CONN_ADD) {
- pthread_t thr;
- struct join_info * inf;
- struct conn * c = (struct conn *) o;
- struct timespec slack = {0, DHT_ENROLL_SLACK * MILLION};
-
- /* Give the pff some time to update for the new link. */
- nanosleep(&slack, NULL);
-
- switch(dht_get_state()) {
- case DHT_INIT:
- inf = malloc(sizeof(*inf));
- if (inf == NULL)
- break;
-
- inf->addr = c->conn_info.addr;
-
- if (dht_set_state(DHT_JOINING) == 0 ||
- dht_wait_running()) {
- if (pthread_create(&thr, NULL, join_thr, inf)) {
- dht_set_state(DHT_INIT);
- free(inf);
- return;
- }
- pthread_detach(thr);
- } else {
- free(inf);
- }
- break;
- case DHT_RUNNING:
- /*
- * FIXME: this lookup for effiency reasons
- * causes a SEGV when stressed with rapid
- * enrollments.
- * lu = kad_lookup(dht, dht.id, KAD_FIND_NODE);
- * if (lu != NULL)
- * lookup_destroy(lu);
- */
- break;
- default:
- break;
- }
- }
-}
-
-int dht_init()
-{
- dht.buckets = NULL;
-
- list_head_init(&dht.entries);
- list_head_init(&dht.requests);
- list_head_init(&dht.refs);
- list_head_init(&dht.lookups);
- list_head_init(&dht.cmds);
-
- if (pthread_rwlock_init(&dht.lock, NULL))
- goto fail_rwlock;
-
- if (pthread_mutex_init(&dht.mtx, NULL))
- goto fail_mutex;
-
- if (pthread_cond_init(&dht.cond, NULL))
- goto fail_cond;
-
- dht.cookies = bmp_create(DHT_MAX_REQS, 1);
- if (dht.cookies == NULL)
- goto fail_bmp;
-
- dht.b = 0;
- dht.id = NULL;
-#ifndef __DHT_TEST__
- dht.addr = ipcpi.dt_addr;
- dht.tpm = tpm_create(2, 1, dht_handle_packet, NULL);
- if (dht.tpm == NULL)
- goto fail_tpm_create;
-
- if (tpm_start(dht.tpm))
- goto fail_tpm_start;
-
- dht.eid = dt_reg_comp(&dht, &dht_post_packet, DHT);
- if ((int) dht.eid < 0)
- goto fail_tpm_start;
-
- notifier_reg(handle_event, NULL);
-#else
- (void) handle_event;
- (void) dht_handle_packet;
- (void) dht_post_packet;
-#endif
- dht.state = DHT_INIT;
-
- return 0;
-#ifndef __DHT_TEST__
- fail_tpm_start:
- tpm_destroy(dht.tpm);
- fail_tpm_create:
- bmp_destroy(dht.cookies);
-#endif
- fail_bmp:
- pthread_cond_destroy(&dht.cond);
- fail_cond:
- pthread_mutex_destroy(&dht.mtx);
- fail_mutex:
- pthread_rwlock_destroy(&dht.lock);
- fail_rwlock:
- return -1;
-}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-01 21:36:26 +0000