/*
* unbound.c - unbound validating resolver public API implementation
*
* Copyright (c) 2007, NLnet Labs. All rights reserved.
*
* This software is open source.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of the NLNET LABS nor the names of its contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/**
* \file
*
* This file contains functions to resolve DNS queries and
* validate the answers. Synchronously and asynchronously.
*
*/
/* include the public api first, it should be able to stand alone */
#include "libunbound/unbound.h"
#include "libunbound/unbound-event.h"
#include "config.h"
#include <ctype.h>
#include "libunbound/context.h"
#include "libunbound/libworker.h"
#include "util/locks.h"
#include "util/config_file.h"
#include "util/alloc.h"
#include "util/module.h"
#include "util/regional.h"
#include "util/log.h"
#include "util/random.h"
#include "util/net_help.h"
#include "util/tube.h"
#include "util/ub_event.h"
#include "services/modstack.h"
#include "services/localzone.h"
#include "services/cache/infra.h"
#include "services/cache/rrset.h"
#include "services/authzone.h"
#include "sldns/sbuffer.h"
#ifdef HAVE_PTHREAD
#include <signal.h>
#endif
#ifdef HAVE_SYS_WAIT_H
#include <sys/wait.h>
#endif
#ifdef HAVE_TIME_H
#include <time.h>
#endif
#if defined(UB_ON_WINDOWS) && defined (HAVE_WINDOWS_H)
#include <windows.h>
#include <iphlpapi.h>
#endif /* UB_ON_WINDOWS */
/** store that the logfile has a debug override */
int ctx_logfile_overridden = 0;
/** create context functionality, but no pipes */
static struct ub_ctx* ub_ctx_create_nopipe(void)
{
struct ub_ctx* ctx;
unsigned int seed;
#ifdef USE_WINSOCK
int r;
WSADATA wsa_data;
#endif
checklock_start();
if(!ctx_logfile_overridden)
log_init(NULL, 0, NULL); /* logs to stderr */
log_ident_set("libunbound");
#ifdef USE_WINSOCK
if((r = WSAStartup(MAKEWORD(2,2), &wsa_data)) != 0) {
log_err("could not init winsock. WSAStartup: %s",
wsa_strerror(r));
return NULL;
}
#endif
verbosity = 0; /* errors only */
checklock_start();
ctx = (struct ub_ctx*)calloc(1, sizeof(*ctx));
if(!ctx) {
errno = ENOMEM;
return NULL;
}
alloc_init(&ctx->superalloc, NULL, 0);
seed = (unsigned int)time(NULL) ^ (unsigned int)getpid();
if(!(ctx->seed_rnd = ub_initstate(seed, NULL))) {
explicit_bzero(&seed, sizeof(seed));
ub_randfree(ctx->seed_rnd);
free(ctx);
errno = ENOMEM;
return NULL;
}
explicit_bzero(&seed, sizeof(seed));
lock_basic_init(&ctx->qqpipe_lock);
lock_basic_init(&ctx->rrpipe_lock);
lock_basic_init(&ctx->cfglock);
ctx->env = (struct module_env*)calloc(1, sizeof(*ctx->env));
if(!ctx->env) {
ub_randfree(ctx->seed_rnd);
free(ctx);
errno = ENOMEM;
return NULL;
}
ctx->env->cfg = config_create_forlib();
if(!ctx->env->cfg) {
free(ctx->env);
ub_randfree(ctx->seed_rnd);
free(ctx);
errno = ENOMEM;
return NULL;
}
/* init edns_known_options */
if(!edns_known_options_init(ctx->env)) {
config_delete(ctx->env->cfg);
free(ctx->env);
ub_randfree(ctx->seed_rnd);
free(ctx);
errno = ENOMEM;
return NULL;
}
ctx->env->auth_zones = auth_zones_create();
if(!ctx->env->auth_zones) {
edns_known_options_delete(ctx->env);
config_delete(ctx->env->cfg);
free(ctx->env);
ub_randfree(ctx->seed_rnd);
free(ctx);
errno = ENOMEM;
return NULL;
}
ctx->env->alloc = &ctx->superalloc;
ctx->env->worker = NULL;
ctx->env->need_to_validate = 0;
modstack_init(&ctx->mods);
rbtree_init(&ctx->queries, &context_query_cmp);
return ctx;
}
struct ub_ctx*
ub_ctx_create(void)
{
struct ub_ctx* ctx = ub_ctx_create_nopipe();
if(!ctx)
return NULL;
if((ctx->qq_pipe = tube_create()) == NULL) {
int e = errno;
ub_randfree(ctx->seed_rnd);
config_delete(ctx->env->cfg);
modstack_desetup(&ctx->mods, ctx->env);
edns_known_options_delete(ctx->env);
free(ctx->env);
free(ctx);
errno = e;
return NULL;
}
if((ctx->rr_pipe = tube_create()) == NULL) {
int e = errno;
tube_delete(ctx->qq_pipe);
ub_randfree(ctx->seed_rnd);
config_delete(ctx->env->cfg);
modstack_desetup(&ctx->mods, ctx->env);
edns_known_options_delete(ctx->env);
free(ctx->env);
free(ctx);
errno = e;
return NULL;
}
return ctx;
}
struct ub_ctx*
ub_ctx_create_ub_event(struct ub_event_base* ueb)
{
struct ub_ctx* ctx = ub_ctx_create_nopipe();
if(!ctx)
return NULL;
/* no pipes, but we have the locks to make sure everything works */
ctx->created_bg = 0;
ctx->dothread = 1; /* the processing is in the same process,
makes ub_cancel and ub_ctx_delete do the right thing */
ctx->event_base = ueb;
return ctx;
}
struct ub_ctx*
ub_ctx_create_event(struct event_base* eb)
{
struct ub_ctx* ctx = ub_ctx_create_nopipe();
if(!ctx)
return NULL;
/* no pipes, but we have the locks to make sure everything works */
ctx->created_bg = 0;
ctx->dothread = 1; /* the processing is in the same process,
makes ub_cancel and ub_ctx_delete do the right thing */
ctx->event_base = ub_libevent_event_base(eb);
if (!ctx->event_base) {
ub_ctx_delete(ctx);
return NULL;
}
return ctx;
}
/** delete q */
static void
delq(rbnode_type* n, void* ATTR_UNUSED(arg))
{
struct ctx_query* q = (struct ctx_query*)n;
context_query_delete(q);
}
/** stop the bg thread */
static void ub_stop_bg(struct ub_ctx* ctx)
{
/* stop the bg thread */
lock_basic_lock(&ctx->cfglock);
if(ctx->created_bg) {
uint8_t* msg;
uint32_t len;
uint32_t cmd = UB_LIBCMD_QUIT;
lock_basic_unlock(&ctx->cfglock);
lock_basic_lock(&ctx->qqpipe_lock);
(void)tube_write_msg(ctx->qq_pipe, (uint8_t*)&cmd,
(uint32_t)sizeof(cmd), 0);
lock_basic_unlock(&ctx->qqpipe_lock);
lock_basic_lock(&ctx->rrpipe_lock);
while(tube_read_msg(ctx->rr_pipe, &msg, &len, 0)) {
/* discard all results except a quit confirm */
if(context_serial_getcmd(msg, len) == UB_LIBCMD_QUIT) {
free(msg);
break;
}
free(msg);
}
lock_basic_unlock(&ctx->rrpipe_lock);
/* if bg worker is a thread, wait for it to exit, so that all
* resources are really gone. */
lock_basic_lock(&ctx->cfglock);
if(ctx->dothread) {
lock_basic_unlock(&ctx->cfglock);
ub_thread_join(ctx->bg_tid);
} else {
lock_basic_unlock(&ctx->cfglock);
#ifndef UB_ON_WINDOWS
if(waitpid(ctx->bg_pid, NULL, 0) == -1) {
if(verbosity > 2)
log_err("waitpid: %s", strerror(errno));
}
#endif
}
}
else {
lock_basic_unlock(&ctx->cfglock);
}
}
void
ub_ctx_delete(struct ub_ctx* ctx)
{
struct alloc_cache* a, *na;
int do_stop = 1;
if(!ctx) return;
/* see if bg thread is created and if threads have been killed */
/* no locks, because those may be held by terminated threads */
/* for processes the read pipe is closed and we see that on read */
#ifdef HAVE_PTHREAD
if(ctx->created_bg && ctx->dothread) {
if(pthread_kill(ctx->bg_tid, 0) == ESRCH) {
/* thread has been killed */
do_stop = 0;
}
}
#endif /* HAVE_PTHREAD */
if(do_stop)
ub_stop_bg(ctx);
libworker_delete_event(ctx->event_worker);
modstack_desetup(&ctx->mods, ctx->env);
a = ctx->alloc_list;
while(a) {
na = a->super;
a->super = &ctx->superalloc;
alloc_clear(a);
free(a);
a = na;
}
local_zones_delete(ctx->local_zones);
lock_basic_destroy(&ctx->qqpipe_lock);
lock_basic_destroy(&ctx->rrpipe_lock);
lock_basic_destroy(&ctx->cfglock);
tube_delete(ctx->qq_pipe);
tube_delete(ctx->rr_pipe);
if(ctx->env) {
slabhash_delete(ctx->env->msg_cache);
rrset_cache_delete(ctx->env->rrset_cache);
infra_delete(ctx->env->infra_cache);
config_delete(ctx->env->cfg);
edns_known_options_delete(ctx->env);
auth_zones_delete(ctx->env->auth_zones);
free(ctx->env);
}
ub_randfree(ctx->seed_rnd);
alloc_clear(&ctx->superalloc);
traverse_postorder(&ctx->queries, delq, NULL);
if(ctx_logfile_overridden) {
log_file(NULL);
ctx_logfile_overridden = 0;
}
free(ctx);
#ifdef USE_WINSOCK
WSACleanup();
#endif
}
int
ub_ctx_set_option(struct ub_ctx* ctx, const char* opt, const char* val)
{
lock_basic_lock(&ctx->cfglock);
if(ctx->finalized) {
lock_basic_unlock(&ctx->cfglock);
return UB_AFTERFINAL;
}
if(!config_set_option(ctx->env->cfg, opt, val)) {
lock_basic_unlock(&ctx->cfglock);
return UB_SYNTAX;
}
lock_basic_unlock(&ctx->cfglock);
return UB_NOERROR;
}
int
ub_ctx_get_option(struct ub_ctx* ctx, const char* opt, char** str)
{
int r;
lock_basic_lock(&ctx->cfglock);
r = config_get_option_collate(ctx->env->cfg, opt, str);
lock_basic_unlock(&ctx->cfglock);
if(r == 0) r = UB_NOERROR;
else if(r == 1) r = UB_SYNTAX;
else if(r == 2) r = UB_NOMEM;
return r;
}
int
ub_ctx_config(struct ub_ctx* ctx, const char* fname)
{
lock_basic_lock(&ctx->cfglock);
if(ctx->finalized) {
lock_basic_unlock(&ctx->cfglock);
return UB_AFTERFINAL;
}
if(!config_read(ctx->env->cfg, fname, NULL)) {
lock_basic_unlock(&ctx->cfglock);
return UB_SYNTAX;
}
lock_basic_unlock(&ctx->cfglock);
return UB_NOERROR;
}
int
ub_ctx_add_ta(struct ub_ctx* ctx, const char* ta)
{
char* dup = strdup(ta);
if(!dup) return UB_NOMEM;
lock_basic_lock(&ctx->cfglock);
if(ctx->finalized) {
lock_basic_unlock(&ctx->cfglock);
free(dup);
return UB_AFTERFINAL;
}
if(!cfg_strlist_insert(&ctx->env->cfg->trust_anchor_list, dup)) {
lock_basic_unlock(&ctx->cfglock);
return UB_NOMEM;
}
lock_basic_unlock(&ctx->cfglock);
return UB_NOERROR;
}
int
ub_ctx_add_ta_file(struct ub_ctx* ctx, const char* fname)
{
char* dup = strdup(fname);
if(!dup) return UB_NOMEM;
lock_basic_lock(&ctx->cfglock);
if(ctx->finalized) {
lock_basic_unlock(&ctx->cfglock);
free(dup);
return UB_AFTERFINAL;
}
if(!cfg_strlist_insert(&ctx->env->cfg->trust_anchor_file_list, dup)) {
lock_basic_unlock(&ctx->cfglock);
return UB_NOMEM;
}
lock_basic_unlock(&ctx->cfglock);
return UB_NOERROR;
}
int ub_ctx_add_ta_autr(struct ub_ctx* ctx, const char* fname)
{
char* dup = strdup(fname);
if(!dup) return UB_NOMEM;
lock_basic_lock(&ctx->cfglock);
if(ctx->finalized) {
lock_basic_unlock(&ctx->cfglock);
free(dup);
return UB_AFTERFINAL;
}
if(!cfg_strlist_insert(&ctx->env->cfg->auto_trust_anchor_file_list,
dup)) {
lock_basic_unlock(&ctx->cfglock);
return UB_NOMEM;
}
lock_basic_unlock(&ctx->cfglock);
return UB_NOERROR;
}
int
ub_ctx_trustedkeys(struct ub_ctx* ctx, const char* fname)
{
char* dup = strdup(fname);
if(!dup) return UB_NOMEM;
lock_basic_lock(&ctx->cfglock);
if(ctx->finalized) {
lock_basic_unlock(&ctx->cfglock);
free(dup);
return UB_AFTERFINAL;
}
if(!cfg_strlist_insert(&ctx->env->cfg->trusted_keys_file_list, dup)) {
lock_basic_unlock(&ctx->cfglock);
return UB_NOMEM;
}
lock_basic_unlock(&ctx->cfglock);
return UB_NOERROR;
}
int
ub_ctx_debuglevel(struct ub_ctx* ctx, int d)
{
lock_basic_lock(&ctx->cfglock);
verbosity = d;
ctx->env->cfg->verbosity = d;
lock_basic_unlock(&ctx->cfglock);
return UB_NOERROR;
}
int ub_ctx_debugout(struct ub_ctx* ctx, void* out)
{
lock_basic_lock(&ctx->cfglock);
log_file((FILE*)out);
ctx_logfile_overridden = 1;
ctx->logfile_override = 1;
ctx->log_out = out;
lock_basic_unlock(&ctx->cfglock);
return UB_NOERROR;
}
int
ub_ctx_async(struct ub_ctx* ctx, int dothread)
{
#ifdef THREADS_DISABLED
if(dothread) /* cannot do threading */
return UB_NOERROR;
#endif
lock_basic_lock(&ctx->cfglock);
if(ctx->finalized) {
lock_basic_unlock(&ctx->cfglock);
return UB_AFTERFINAL;
}
ctx->dothread = dothread;
lock_basic_unlock(&ctx->cfglock);
return UB_NOERROR;
}
int
ub_poll(struct ub_ctx* ctx)
{
/* no need to hold lock while testing for readability. */
return tube_poll(ctx->rr_pipe);
}
int
ub_fd(struct ub_ctx* ctx)
{
return tube_read_fd(ctx->rr_pipe);
}
/** process answer from bg worker */
static int
process_answer_detail(struct ub_ctx* ctx, uint8_t* msg, uint32_t len,
ub_callback_type* cb, void** cbarg, int* err,
struct ub_result** res)
{
struct ctx_query* q;
if(context_serial_getcmd(msg, len) != UB_LIBCMD_ANSWER) {
log_err("error: bad data from bg worker %d",
(int)context_serial_getcmd(msg, len));
return 0;
}
lock_basic_lock(&ctx->cfglock);
q = context_deserialize_answer(ctx, msg, len, err);
if(!q) {
lock_basic_unlock(&ctx->cfglock);
/* probably simply the lookup that failed, i.e.
* response returned before cancel was sent out, so noerror */
return 1;
}
log_assert(q->async);
/* grab cb while locked */
if(q->cancelled) {
*cb = NULL;
*cbarg = NULL;
} else {
*cb = q->cb;
*cbarg = q->cb_arg;
}
if(*err) {
*res = NULL;
ub_resolve_free(q->res);
} else {
/* parse the message, extract rcode, fill result */
sldns_buffer* buf = sldns_buffer_new(q->msg_len);
struct regional* region = regional_create();
*res = q->res;
(*res)->rcode = LDNS_RCODE_SERVFAIL;
if(region && buf) {
sldns_buffer_clear(buf);
sldns_buffer_write(buf, q->msg, q->msg_len);
sldns_buffer_flip(buf);
libworker_enter_result(*res, buf, region,
q->msg_security);
}
(*res)->answer_packet = q->msg;
(*res)->answer_len = (int)q->msg_len;
q->msg = NULL;
sldns_buffer_free(buf);
regional_destroy(region);
}
q->res = NULL;
/* delete the q from list */
(void)rbtree_delete(&ctx->queries, q->node.key);
ctx->num_async--;
context_query_delete(q);
lock_basic_unlock(&ctx->cfglock);
if(*cb) return 2;
ub_resolve_free(*res);
return 1;
}
/** process answer from bg worker */
static int
process_answer(struct ub_ctx* ctx, uint8_t* msg, uint32_t len)
{
int err;
ub_callback_type cb;
void* cbarg;
struct ub_result* res;
int r;
r = process_answer_detail(ctx, msg, len, &cb, &cbarg, &err, &res);
/* no locks held while calling callback, so that library is
* re-entrant. */
if(r == 2)
(*cb)(cbarg, err, res);
return r;
}
int
ub_process(struct ub_ctx* ctx)
{
int r;
uint8_t* msg;
uint32_t len;
while(1) {
msg = NULL;
lock_basic_lock(&ctx->rrpipe_lock);
r = tube_read_msg(ctx->rr_pipe, &msg, &len, 1);
lock_basic_unlock(&ctx->rrpipe_lock);
if(r == 0)
return UB_PIPE;
else if(r == -1)
break;
if(!process_answer(ctx, msg, len)) {
free(msg);
return UB_PIPE;
}
free(msg);
}
return UB_NOERROR;
}
int
ub_wait(struct ub_ctx* ctx)
{
int err;
ub_callback_type cb;
void* cbarg;
struct ub_result* res;
int r;
uint8_t* msg;
uint32_t len;
/* this is basically the same loop as _process(), but with changes.
* holds the rrpipe lock and waits with tube_wait */
while(1) {
lock_basic_lock(&ctx->rrpipe_lock);
lock_basic_lock(&ctx->cfglock);
if(ctx->num_async == 0) {
lock_basic_unlock(&ctx->cfglock);
lock_basic_unlock(&ctx->rrpipe_lock);
break;
}
lock_basic_unlock(&ctx->cfglock);
/* keep rrpipe locked, while
* o waiting for pipe readable
* o parsing message
* o possibly decrementing num_async
* do callback without lock
*/
r = tube_wait(ctx->rr_pipe);
if(r) {
r = tube_read_msg(ctx->rr_pipe, &msg, &len, 1);
if(r == 0) {
lock_basic_unlock(&ctx->rrpipe_lock);
return UB_PIPE;
}
if(r == -1) {
lock_basic_unlock(&ctx->rrpipe_lock);
continue;
}
r = process_answer_detail(ctx, msg, len,
&cb, &cbarg, &err, &res);
lock_basic_unlock(&ctx->rrpipe_lock);
free(msg);
if(r == 0)
return UB_PIPE;
if(r == 2)
(*cb)(cbarg, err, res);
} else {
lock_basic_unlock(&ctx->rrpipe_lock);
}
}
return UB_NOERROR;
}
int
ub_resolve(struct ub_ctx* ctx, const char* name, int rrtype,
int rrclass, struct ub_result** result)
{
struct ctx_query* q;
int r;
*result = NULL;
lock_basic_lock(&ctx->cfglock);
if(!ctx->finalized) {
r = context_finalize(ctx);
if(r) {
lock_basic_unlock(&ctx->cfglock);
return r;
}
}
/* create new ctx_query and attempt to add to the list */
lock_basic_unlock(&ctx->cfglock);
q = context_new(ctx, name, rrtype, rrclass, NULL, NULL, NULL);
if(!q)
return UB_NOMEM;
/* become a resolver thread for a bit */
r = libworker_fg(ctx, q);
if(r) {
lock_basic_lock(&ctx->cfglock);
(void)rbtree_delete(&ctx->queries, q->node.key);
context_query_delete(q);
lock_basic_unlock(&ctx->cfglock);
return r;
}
q->res->answer_packet = q->msg;
q->res->answer_len = (int)q->msg_len;
q->msg = NULL;
*result = q->res;
q->res = NULL;
lock_basic_lock(&ctx->cfglock);
(void)rbtree_delete(&ctx->queries, q->node.key);
context_query_delete(q);
lock_basic_unlock(&ctx->cfglock);
return UB_NOERROR;
}
int
ub_resolve_event(struct ub_ctx* ctx, const char* name, int rrtype,
int rrclass, void* mydata, ub_event_callback_type callback,
int* async_id)
{
struct ctx_query* q;
int r;
if(async_id)
*async_id = 0;
lock_basic_lock(&ctx->cfglock);
if(!ctx->finalized) {
r = context_finalize(ctx);
if(r) {
lock_basic_unlock(&ctx->cfglock);
return r;
}
}
lock_basic_unlock(&ctx->cfglock);
if(!ctx->event_worker) {
ctx->event_worker = libworker_create_event(ctx,
ctx->event_base);
if(!ctx->event_worker) {
return UB_INITFAIL;
}
}
/* set time in case answer comes from cache */
ub_comm_base_now(ctx->event_worker->base);
/* create new ctx_query and attempt to add to the list */
q = context_new(ctx, name, rrtype, rrclass, NULL, callback, mydata);
if(!q)
return UB_NOMEM;
/* attach to mesh */
if((r=libworker_attach_mesh(ctx, q, async_id)) != 0)
return r;
return UB_NOERROR;
}
int
ub_resolve_async(struct ub_ctx* ctx, const char* name, int rrtype,
int rrclass, void* mydata, ub_callback_type callback, int* async_id)
{
struct ctx_query* q;
uint8_t* msg = NULL;
uint32_t len = 0;
if(async_id)
*async_id = 0;
lock_basic_lock(&ctx->cfglock);
if(!ctx->finalized) {
int r = context_finalize(ctx);
if(r) {
lock_basic_unlock(&ctx->cfglock);
return r;
}
}
if(!ctx->created_bg) {
int r;
ctx->created_bg = 1;
lock_basic_unlock(&ctx->cfglock);
r = libworker_bg(ctx);
if(r) {
lock_basic_lock(&ctx->cfglock);
ctx->created_bg = 0;
lock_basic_unlock(&ctx->cfglock);
return r;
}
} else {
lock_basic_unlock(&ctx->cfglock);
}
/* create new ctx_query and attempt to add to the list */
q = context_new(ctx, name, rrtype, rrclass, callback, NULL, mydata);
if(!q)
return UB_NOMEM;
/* write over pipe to background worker */
lock_basic_lock(&ctx->cfglock);
msg = context_serialize_new_query(q, &len);
if(!msg) {
(void)rbtree_delete(&ctx->queries, q->node.key);
ctx->num_async--;
context_query_delete(q);
lock_basic_unlock(&ctx->cfglock);
return UB_NOMEM;
}
if(async_id)
*async_id = q->querynum;
lock_basic_unlock(&ctx->cfglock);
lock_basic_lock(&ctx->qqpipe_lock);
if(!tube_write_msg(ctx->qq_pipe, msg, len, 0)) {
lock_basic_unlock(&ctx->qqpipe_lock);
free(msg);
return UB_PIPE;
}
lock_basic_unlock(&ctx->qqpipe_lock);
free(msg);
return UB_NOERROR;
}
int
ub_cancel(struct ub_ctx* ctx, int async_id)
{
struct ctx_query* q;
uint8_t* msg = NULL;
uint32_t len = 0;
lock_basic_lock(&ctx->cfglock);
q = (struct ctx_query*)rbtree_search(&ctx->queries, &async_id);
if(!q || !q->async) {
/* it is not there, so nothing to do */
lock_basic_unlock(&ctx->cfglock);
return UB_NOID;
}
log_assert(q->async);
q->cancelled = 1;
/* delete it */
if(!ctx->dothread) { /* if forked */
(void)rbtree_delete(&ctx->queries, q->node.key);
ctx->num_async--;
msg = context_serialize_cancel(q, &len);
context_query_delete(q);
lock_basic_unlock(&ctx->cfglock);
if(!msg) {
return UB_NOMEM;
}
/* send cancel to background worker */
lock_basic_lock(&ctx->qqpipe_lock);
if(!tube_write_msg(ctx->qq_pipe, msg, len, 0)) {
lock_basic_unlock(&ctx->qqpipe_lock);
free(msg);
return UB_PIPE;
}
lock_basic_unlock(&ctx->qqpipe_lock);
free(msg);
} else {
lock_basic_unlock(&ctx->cfglock);
}
return UB_NOERROR;
}
void
ub_resolve_free(struct ub_result* result)
{
char** p;
if(!result) return;
free(result->qname);
if(result->canonname != result->qname)
free(result->canonname);
if(result->data)
for(p = result->data; *p; p++)
free(*p);
free(result->data);
free(result->len);
free(result->answer_packet);
free(result->why_bogus);
free(result);
}
const char*
ub_strerror(int err)
{
switch(err) {
case UB_NOERROR: return "no error";
case UB_SOCKET: return "socket io error";
case UB_NOMEM: return "out of memory";
case UB_SYNTAX: return "syntax error";
case UB_SERVFAIL: return "server failure";
case UB_FORKFAIL: return "could not fork";
case UB_INITFAIL: return "initialization failure";
case UB_AFTERFINAL: return "setting change after finalize";
case UB_PIPE: return "error in pipe communication with async";
case UB_READFILE: return "error reading file";
case UB_NOID: return "error async_id does not exist";
default: return "unknown error";
}
}
int
ub_ctx_set_fwd(struct ub_ctx* ctx, const char* addr)
{
struct sockaddr_storage storage;
socklen_t stlen;
struct config_stub* s;
char* dupl;
lock_basic_lock(&ctx->cfglock);
if(ctx->finalized) {
lock_basic_unlock(&ctx->cfglock);
errno=EINVAL;
return UB_AFTERFINAL;
}
if(!addr) {
/* disable fwd mode - the root stub should be first. */
if(ctx->env->cfg->forwards &&
strcmp(ctx->env->cfg->forwards->name, ".") == 0) {
s = ctx->env->cfg->forwards;
ctx->env->cfg->forwards = s->next;
s->next = NULL;
config_delstubs(s);
}
lock_basic_unlock(&ctx->cfglock);
return UB_NOERROR;
}
lock_basic_unlock(&ctx->cfglock);
/* check syntax for addr */
if(!extstrtoaddr(addr, &storage, &stlen)) {
errno=EINVAL;
return UB_SYNTAX;
}
/* it parses, add root stub in front of list */
lock_basic_lock(&ctx->cfglock);
if(!ctx->env->cfg->forwards ||
strcmp(ctx->env->cfg->forwards->name, ".") != 0) {
s = calloc(1, sizeof(*s));
if(!s) {
lock_basic_unlock(&ctx->cfglock);
errno=ENOMEM;
return UB_NOMEM;
}
s->name = strdup(".");
if(!s->name) {
free(s);
lock_basic_unlock(&ctx->cfglock);
errno=ENOMEM;
return UB_NOMEM;
}
s->next = ctx->env->cfg->forwards;
ctx->env->cfg->forwards = s;
} else {
log_assert(ctx->env->cfg->forwards);
s = ctx->env->cfg->forwards;
}
dupl = strdup(addr);
if(!dupl) {
lock_basic_unlock(&ctx->cfglock);
errno=ENOMEM;
return UB_NOMEM;
}
if(!cfg_strlist_insert(&s->addrs, dupl)) {
lock_basic_unlock(&ctx->cfglock);
errno=ENOMEM;
return UB_NOMEM;
}
lock_basic_unlock(&ctx->cfglock);
return UB_NOERROR;
}
int ub_ctx_set_tls(struct ub_ctx* ctx, int tls)
{
lock_basic_lock(&ctx->cfglock);
if(ctx->finalized) {
lock_basic_unlock(&ctx->cfglock);
errno=EINVAL;
return UB_AFTERFINAL;
}
ctx->env->cfg->ssl_upstream = tls;
lock_basic_unlock(&ctx->cfglock);
return UB_NOERROR;
}
int ub_ctx_set_stub(struct ub_ctx* ctx, const char* zone, const char* addr,
int isprime)
{
char* a;
struct config_stub **prev, *elem;
/* check syntax for zone name */
if(zone) {
uint8_t* nm;
int nmlabs;
size_t nmlen;
if(!parse_dname(zone, &nm, &nmlen, &nmlabs)) {
errno=EINVAL;
return UB_SYNTAX;
}
free(nm);
} else {
zone = ".";
}
/* check syntax for addr (if not NULL) */
if(addr) {
struct sockaddr_storage storage;
socklen_t stlen;
if(!extstrtoaddr(addr, &storage, &stlen)) {
errno=EINVAL;
return UB_SYNTAX;
}
}
lock_basic_lock(&ctx->cfglock);
if(ctx->finalized) {
lock_basic_unlock(&ctx->cfglock);
errno=EINVAL;
return UB_AFTERFINAL;
}
/* arguments all right, now find or add the stub */
prev = &ctx->env->cfg->stubs;
elem = cfg_stub_find(&prev, zone);
if(!elem && !addr) {
/* not found and we want to delete, nothing to do */
lock_basic_unlock(&ctx->cfglock);
return UB_NOERROR;
} else if(elem && !addr) {
/* found, and we want to delete */
*prev = elem->next;
config_delstub(elem);
lock_basic_unlock(&ctx->cfglock);
return UB_NOERROR;
} else if(!elem) {
/* not found, create the stub entry */
elem=(struct config_stub*)calloc(1, sizeof(struct config_stub));
if(elem) elem->name = strdup(zone);
if(!elem || !elem->name) {
free(elem);
lock_basic_unlock(&ctx->cfglock);
errno = ENOMEM;
return UB_NOMEM;
}
elem->next = ctx->env->cfg->stubs;
ctx->env->cfg->stubs = elem;
}
/* add the address to the list and set settings */
elem->isprime = isprime;
a = strdup(addr);
if(!a) {
lock_basic_unlock(&ctx->cfglock);
errno = ENOMEM;
return UB_NOMEM;
}
if(!cfg_strlist_insert(&elem->addrs, a)) {
lock_basic_unlock(&ctx->cfglock);
errno = ENOMEM;
return UB_NOMEM;
}
lock_basic_unlock(&ctx->cfglock);
return UB_NOERROR;
}
int
ub_ctx_resolvconf(struct ub_ctx* ctx, const char* fname)
{
FILE* in;
int numserv = 0;
char buf[1024];
char* parse, *addr;
int r;
if(fname == NULL) {
#if !defined(UB_ON_WINDOWS) || !defined(HAVE_WINDOWS_H)
fname = "/etc/resolv.conf";
#else
FIXED_INFO *info;
ULONG buflen = sizeof(*info);
IP_ADDR_STRING *ptr;
info = (FIXED_INFO *) malloc(sizeof (FIXED_INFO));
if (info == NULL)
return UB_READFILE;
if (GetNetworkParams(info, &buflen) == ERROR_BUFFER_OVERFLOW) {
free(info);
info = (FIXED_INFO *) malloc(buflen);
if (info == NULL)
return UB_READFILE;
}
if (GetNetworkParams(info, &buflen) == NO_ERROR) {
int retval=0;
ptr = &(info->DnsServerList);
while (ptr) {
numserv++;
if((retval=ub_ctx_set_fwd(ctx,
ptr->IpAddress.String))!=0) {
free(info);
return retval;
}
ptr = ptr->Next;
}
free(info);
if (numserv==0)
return UB_READFILE;
return UB_NOERROR;
}
free(info);
return UB_READFILE;
#endif /* WINDOWS */
}
in = fopen(fname, "r");
if(!in) {
/* error in errno! perror(fname) */
return UB_READFILE;
}
while(fgets(buf, (int)sizeof(buf), in)) {
buf[sizeof(buf)-1] = 0;
parse=buf;
while(*parse == ' ' || *parse == '\t')
parse++;
if(strncmp(parse, "nameserver", 10) == 0) {
numserv++;
parse += 10; /* skip 'nameserver' */
/* skip whitespace */
while(*parse == ' ' || *parse == '\t')
parse++;
addr = parse;
/* skip [0-9a-fA-F.:]*, i.e. IP4 and IP6 address */
while(isxdigit((unsigned char)*parse) || *parse=='.' || *parse==':')
parse++;
/* terminate after the address, remove newline */
*parse = 0;
if((r = ub_ctx_set_fwd(ctx, addr)) != UB_NOERROR) {
fclose(in);
return r;
}
}
}
fclose(in);
if(numserv == 0) {
/* from resolv.conf(5) if none given, use localhost */
return ub_ctx_set_fwd(ctx, "127.0.0.1");
}
return UB_NOERROR;
}
int
ub_ctx_hosts(struct ub_ctx* ctx, const char* fname)
{
FILE* in;
char buf[1024], ldata[2048];
char* parse, *addr, *name, *ins;
lock_basic_lock(&ctx->cfglock);
if(ctx->finalized) {
lock_basic_unlock(&ctx->cfglock);
errno=EINVAL;
return UB_AFTERFINAL;
}
lock_basic_unlock(&ctx->cfglock);
if(fname == NULL) {
#if defined(UB_ON_WINDOWS) && defined(HAVE_WINDOWS_H)
/*
* If this is Windows NT/XP/2K it's in
* %WINDIR%\system32\drivers\etc\hosts.
* If this is Windows 95/98/Me it's in %WINDIR%\hosts.
*/
name = getenv("WINDIR");
if (name != NULL) {
int retval=0;
snprintf(buf, sizeof(buf), "%s%s", name,
"\\system32\\drivers\\etc\\hosts");
if((retval=ub_ctx_hosts(ctx, buf)) !=0 ) {
snprintf(buf, sizeof(buf), "%s%s", name,
"\\hosts");
retval=ub_ctx_hosts(ctx, buf);
}
return retval;
}
return UB_READFILE;
#else
fname = "/etc/hosts";
#endif /* WIN32 */
}
in = fopen(fname, "r");
if(!in) {
/* error in errno! perror(fname) */
return UB_READFILE;
}
while(fgets(buf, (int)sizeof(buf), in)) {
buf[sizeof(buf)-1] = 0;
parse=buf;
while(*parse == ' ' || *parse == '\t')
parse++;
if(*parse == '#')
continue; /* skip comment */
/* format: <addr> spaces <name> spaces <name> ... */
addr = parse;
/* skip addr */
while(isxdigit((unsigned char)*parse) || *parse == '.' || *parse == ':')
parse++;
if(*parse == '\r')
parse++;
if(*parse == '\n' || *parse == 0)
continue;
if(*parse == '%')
continue; /* ignore macOSX fe80::1%lo0 localhost */
if(*parse != ' ' && *parse != '\t') {
/* must have whitespace after address */
fclose(in);
errno=EINVAL;
return UB_SYNTAX;
}
*parse++ = 0; /* end delimiter for addr ... */
/* go to names and add them */
while(*parse) {
while(*parse == ' ' || *parse == '\t' || *parse=='\n'
|| *parse=='\r')
parse++;
if(*parse == 0 || *parse == '#')
break;
/* skip name, allows (too) many printable characters */
name = parse;
while('!' <= *parse && *parse <= '~')
parse++;
if(*parse)
*parse++ = 0; /* end delimiter for name */
snprintf(ldata, sizeof(ldata), "%s %s %s",
name, str_is_ip6(addr)?"AAAA":"A", addr);
ins = strdup(ldata);
if(!ins) {
/* out of memory */
fclose(in);
errno=ENOMEM;
return UB_NOMEM;
}
lock_basic_lock(&ctx->cfglock);
if(!cfg_strlist_insert(&ctx->env->cfg->local_data,
ins)) {
lock_basic_unlock(&ctx->cfglock);
fclose(in);
errno=ENOMEM;
return UB_NOMEM;
}
lock_basic_unlock(&ctx->cfglock);
}
}
fclose(in);
return UB_NOERROR;
}
/** finalize the context, if not already finalized */
static int ub_ctx_finalize(struct ub_ctx* ctx)
{
int res = 0;
lock_basic_lock(&ctx->cfglock);
if (!ctx->finalized) {
res = context_finalize(ctx);
}
lock_basic_unlock(&ctx->cfglock);
return res;
}
/* Print local zones and RR data */
int ub_ctx_print_local_zones(struct ub_ctx* ctx)
{
int res = ub_ctx_finalize(ctx);
if (res) return res;
local_zones_print(ctx->local_zones);
return UB_NOERROR;
}
/* Add a new zone */
int ub_ctx_zone_add(struct ub_ctx* ctx, const char *zone_name,
const char *zone_type)
{
enum localzone_type t;
struct local_zone* z;
uint8_t* nm;
int nmlabs;
size_t nmlen;
int res = ub_ctx_finalize(ctx);
if (res) return res;
if(!local_zone_str2type(zone_type, &t)) {
return UB_SYNTAX;
}
if(!parse_dname(zone_name, &nm, &nmlen, &nmlabs)) {
return UB_SYNTAX;
}
lock_rw_wrlock(&ctx->local_zones->lock);
if((z=local_zones_find(ctx->local_zones, nm, nmlen, nmlabs,
LDNS_RR_CLASS_IN))) {
/* already present in tree */
lock_rw_wrlock(&z->lock);
z->type = t; /* update type anyway */
lock_rw_unlock(&z->lock);
lock_rw_unlock(&ctx->local_zones->lock);
free(nm);
return UB_NOERROR;
}
if(!local_zones_add_zone(ctx->local_zones, nm, nmlen, nmlabs,
LDNS_RR_CLASS_IN, t)) {
lock_rw_unlock(&ctx->local_zones->lock);
return UB_NOMEM;
}
lock_rw_unlock(&ctx->local_zones->lock);
return UB_NOERROR;
}
/* Remove zone */
int ub_ctx_zone_remove(struct ub_ctx* ctx, const char *zone_name)
{
struct local_zone* z;
uint8_t* nm;
int nmlabs;
size_t nmlen;
int res = ub_ctx_finalize(ctx);
if (res) return res;
if(!parse_dname(zone_name, &nm, &nmlen, &nmlabs)) {
return UB_SYNTAX;
}
lock_rw_wrlock(&ctx->local_zones->lock);
if((z=local_zones_find(ctx->local_zones, nm, nmlen, nmlabs,
LDNS_RR_CLASS_IN))) {
/* present in tree */
local_zones_del_zone(ctx->local_zones, z);
}
lock_rw_unlock(&ctx->local_zones->lock);
free(nm);
return UB_NOERROR;
}
/* Add new RR data */
int ub_ctx_data_add(struct ub_ctx* ctx, const char *data)
{
int res = ub_ctx_finalize(ctx);
if (res) return res;
res = local_zones_add_RR(ctx->local_zones, data);
return (!res) ? UB_NOMEM : UB_NOERROR;
}
/* Remove RR data */
int ub_ctx_data_remove(struct ub_ctx* ctx, const char *data)
{
uint8_t* nm;
int nmlabs;
size_t nmlen;
int res = ub_ctx_finalize(ctx);
if (res) return res;
if(!parse_dname(data, &nm, &nmlen, &nmlabs))
return UB_SYNTAX;
local_zones_del_data(ctx->local_zones, nm, nmlen, nmlabs,
LDNS_RR_CLASS_IN);
free(nm);
return UB_NOERROR;
}
const char* ub_version(void)
{
return PACKAGE_VERSION;
}
int
ub_ctx_set_event(struct ub_ctx* ctx, struct event_base* base) {
struct ub_event_base* new_base;
if (!ctx || !ctx->event_base || !base) {
return UB_INITFAIL;
}
if (ub_libevent_get_event_base(ctx->event_base) == base) {
/* already set */
return UB_NOERROR;
}
lock_basic_lock(&ctx->cfglock);
/* destroy the current worker - safe to pass in NULL */
libworker_delete_event(ctx->event_worker);
ctx->event_worker = NULL;
new_base = ub_libevent_event_base(base);
if (new_base)
ctx->event_base = new_base;
ctx->created_bg = 0;
ctx->dothread = 1;
lock_basic_unlock(&ctx->cfglock);
return new_base ? UB_NOERROR : UB_INITFAIL;
}