/* Destroy resolver thread synchronization data */
static
void destroy_thread_sync_data(struct thread_sync_data * tsd)
{
if(tsd->mtx) {
Curl_mutex_destroy(tsd->mtx);
free(tsd->mtx);
}
if(tsd->hostname)
free(tsd->hostname);
if(tsd->res)
Curl_freeaddrinfo(tsd->res);
memset(tsd,0,sizeof(*tsd));
}
/*
* destroy_async_data() cleans up async resolver data.
*/
static void destroy_async_data(struct Curl_async *async)
{
free(async->hostname);
if(async->os_specific) {
struct ResolverResults *res = (struct ResolverResults *)async->os_specific;
if(res) {
if(res->temp_ai) {
Curl_freeaddrinfo(res->temp_ai);
res->temp_ai = NULL;
}
free(res);
}
async->os_specific = NULL;
}
async->hostname = NULL;
}
/*
* Curl_resolv_unlock() unlocks the given cached DNS entry. When this has been
* made, the struct may be destroyed due to pruning. It is important that only
* one unlock is made for each Curl_resolv() call.
*/
void Curl_resolv_unlock(struct SessionHandle *data, struct Curl_dns_entry *dns)
{
DEBUGASSERT(dns && (dns->inuse>0));
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
dns->inuse--;
/* only free if nobody is using AND it is not in hostcache (timestamp ==
0) */
if (dns->inuse == 0 && dns->timestamp == 0) {
Curl_freeaddrinfo(dns->addr);
free(dns);
}
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
}
/*
* Curl_addrinfo_callback() gets called by ares, gethostbyname_thread()
* or getaddrinfo_thread() when we got the name resolved (or not!).
*
* If the status argument is CURL_ASYNC_SUCCESS, this function takes
* ownership of the Curl_addrinfo passed, storing the resolved data
* in the DNS cache.
*
* The storage operation locks and unlocks the DNS cache.
*/
CURLcode Curl_addrinfo_callback(struct connectdata *conn,
int status,
struct Curl_addrinfo *ai)
{
struct Curl_dns_entry *dns = NULL;
CURLcode result = CURLE_OK;
conn->async.status = status;
if(CURL_ASYNC_SUCCESS == status) {
if(ai) {
struct SessionHandle *data = conn->data;
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
dns = Curl_cache_addr(data, ai,
conn->async.hostname,
conn->async.port);
if(!dns) {
/* failed to store, cleanup and return error */
Curl_freeaddrinfo(ai);
result = CURLE_OUT_OF_MEMORY;
}
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
}
else {
result = CURLE_OUT_OF_MEMORY;
}
}
conn->async.dns = dns;
/* Set async.done TRUE last in this function since it may be used multi-
threaded and once this is TRUE the other thread may read fields from the
async struct */
conn->async.done = TRUE;
/* IPv4: The input hostent struct will be freed by ares when we return from
this function */
return result;
}
/* Resolve a name and return a pointer in the 'entry' argument if one
is available.
Return codes:
-1 = error, no pointer
0 = OK, pointer provided
1 = waiting for response, no pointer
*/
int Curl_resolv(struct connectdata *conn,
char *hostname,
int port,
struct Curl_dns_entry **entry)
{
char *entry_id = NULL;
struct Curl_dns_entry *dns = NULL;
size_t entry_len;
int wait;
struct SessionHandle *data = conn->data;
CURLcode result;
/* default to failure */
int rc = -1;
*entry = NULL;
#ifdef HAVE_SIGSETJMP
/* this allows us to time-out from the name resolver, as the timeout
will generate a signal and we will siglongjmp() from that here */
if(!data->set.no_signal && sigsetjmp(curl_jmpenv, 1)) {
/* this is coming from a siglongjmp() */
failf(data, "name lookup timed out");
return -1;
}
#endif
/* Create an entry id, based upon the hostname and port */
entry_id = create_hostcache_id(hostname, port, &entry_len);
/* If we can't create the entry id, fail */
if (!entry_id)
return -1;
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
/* See if its already in our dns cache */
dns = Curl_hash_pick(data->hostcache, entry_id, entry_len+1);
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
/* free the allocated entry_id again */
free(entry_id);
if (!dns) {
/* The entry was not in the cache. Resolve it to IP address */
/* If my_getaddrinfo() returns NULL, 'wait' might be set to a non-zero
value indicating that we need to wait for the response to the resolve
call */
Curl_addrinfo *addr = my_getaddrinfo(conn, hostname, port, &wait);
if (!addr) {
if(wait) {
/* the response to our resolve call will come asynchronously at
a later time, good or bad */
/* First, check that we haven't received the info by now */
result = Curl_is_resolved(conn, &dns);
if(result) /* error detected */
return -1;
if(dns)
rc = 0; /* pointer provided */
else
rc = 1; /* no info yet */
}
}
else {
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
/* we got a response, store it in the cache */
dns = cache_resolv_response(data, addr, hostname, port);
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
if(!dns)
/* returned failure, bail out nicely */
Curl_freeaddrinfo(addr);
else
rc = 0;
}
}
else {
dns->inuse++; /* we use it! */
rc = 0;
}
*entry = dns;
return rc;
}
CURLcode Curl_doh_is_resolved(struct connectdata *conn,
struct Curl_dns_entry **dnsp)
{
struct Curl_easy *data = conn->data;
*dnsp = NULL; /* defaults to no response */
if(!data->req.doh.probe[0].easy && !data->req.doh.probe[1].easy) {
failf(data, "Could not DOH-resolve: %s", conn->async.hostname);
return conn->bits.proxy?CURLE_COULDNT_RESOLVE_PROXY:
CURLE_COULDNT_RESOLVE_HOST;
}
else if(!data->req.doh.pending) {
DOHcode rc;
DOHcode rc2;
struct dohentry de;
struct Curl_dns_entry *dns;
struct Curl_addrinfo *ai;
/* remove DOH handles from multi handle and close them */
curl_multi_remove_handle(data->multi, data->req.doh.probe[0].easy);
Curl_close(data->req.doh.probe[0].easy);
curl_multi_remove_handle(data->multi, data->req.doh.probe[1].easy);
Curl_close(data->req.doh.probe[1].easy);
/* parse the responses, create the struct and return it! */
init_dohentry(&de);
rc = doh_decode(data->req.doh.probe[0].serverdoh.memory,
data->req.doh.probe[0].serverdoh.size,
data->req.doh.probe[0].dnstype,
&de);
free(data->req.doh.probe[0].serverdoh.memory);
if(rc) {
infof(data, "DOH: %s type %s for %s\n", doh_strerror(rc),
type2name(data->req.doh.probe[0].dnstype),
data->req.doh.host);
}
rc2 = doh_decode(data->req.doh.probe[1].serverdoh.memory,
data->req.doh.probe[1].serverdoh.size,
data->req.doh.probe[1].dnstype,
&de);
free(data->req.doh.probe[1].serverdoh.memory);
if(rc2) {
infof(data, "DOH: %s type %s for %s\n", doh_strerror(rc2),
type2name(data->req.doh.probe[1].dnstype),
data->req.doh.host);
}
if(!rc || !rc2) {
infof(data, "DOH Host name: %s\n", data->req.doh.host);
showdoh(data, &de);
ai = doh2ai(&de, data->req.doh.host, data->req.doh.port);
if(!ai) {
de_cleanup(&de);
return CURLE_OUT_OF_MEMORY;
}
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
/* we got a response, store it in the cache */
dns = Curl_cache_addr(data, ai, data->req.doh.host, data->req.doh.port);
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
de_cleanup(&de);
if(!dns)
/* returned failure, bail out nicely */
Curl_freeaddrinfo(ai);
else {
conn->async.dns = dns;
*dnsp = dns;
return CURLE_OK;
}
}
de_cleanup(&de);
return CURLE_COULDNT_RESOLVE_HOST;
}
return CURLE_OK;
}
static Curl_addrinfo *
doh2ai(const struct dohentry *de, const char *hostname, int port)
{
Curl_addrinfo *ai;
Curl_addrinfo *prevai = NULL;
Curl_addrinfo *firstai = NULL;
struct sockaddr_in *addr;
#ifdef ENABLE_IPV6
struct sockaddr_in6 *addr6;
#endif
CURLcode result = CURLE_OK;
int i;
if(!de)
/* no input == no output! */
return NULL;
for(i = 0; i < de->numaddr; i++) {
size_t ss_size;
CURL_SA_FAMILY_T addrtype;
if(de->addr[i].type == DNS_TYPE_AAAA) {
#ifndef ENABLE_IPV6
/* we can't handle IPv6 addresses */
continue;
#else
ss_size = sizeof(struct sockaddr_in6);
addrtype = AF_INET6;
#endif
}
else {
ss_size = sizeof(struct sockaddr_in);
addrtype = AF_INET;
}
ai = calloc(1, sizeof(Curl_addrinfo));
if(!ai) {
result = CURLE_OUT_OF_MEMORY;
break;
}
ai->ai_canonname = strdup(hostname);
if(!ai->ai_canonname) {
result = CURLE_OUT_OF_MEMORY;
free(ai);
break;
}
ai->ai_addr = calloc(1, ss_size);
if(!ai->ai_addr) {
result = CURLE_OUT_OF_MEMORY;
free(ai->ai_canonname);
free(ai);
break;
}
if(!firstai)
/* store the pointer we want to return from this function */
firstai = ai;
if(prevai)
/* make the previous entry point to this */
prevai->ai_next = ai;
ai->ai_family = addrtype;
/* we return all names as STREAM, so when using this address for TFTP
the type must be ignored and conn->socktype be used instead! */
ai->ai_socktype = SOCK_STREAM;
ai->ai_addrlen = (curl_socklen_t)ss_size;
/* leave the rest of the struct filled with zero */
switch(ai->ai_family) {
case AF_INET:
addr = (void *)ai->ai_addr; /* storage area for this info */
DEBUGASSERT(sizeof(struct in_addr) == sizeof(de->addr[i].ip.v4));
memcpy(&addr->sin_addr, &de->addr[i].ip.v4, sizeof(struct in_addr));
addr->sin_family = (CURL_SA_FAMILY_T)addrtype;
addr->sin_port = htons((unsigned short)port);
break;
#ifdef ENABLE_IPV6
case AF_INET6:
addr6 = (void *)ai->ai_addr; /* storage area for this info */
DEBUGASSERT(sizeof(struct in6_addr) == sizeof(de->addr[i].ip.v6));
memcpy(&addr6->sin6_addr, &de->addr[i].ip.v6, sizeof(struct in6_addr));
addr6->sin6_family = (CURL_SA_FAMILY_T)addrtype;
addr6->sin6_port = htons((unsigned short)port);
break;
#endif
}
prevai = ai;
}
if(result) {
Curl_freeaddrinfo(firstai);
firstai = NULL;
}
return firstai;
}
int Curl_resolv(struct connectdata *conn,
const char *hostname,
int port,
struct Curl_dns_entry **entry)
{
char *entry_id = NULL;
struct Curl_dns_entry *dns = NULL;
size_t entry_len;
struct SessionHandle *data = conn->data;
CURLcode result;
int rc = CURLRESOLV_ERROR; /* default to failure */
*entry = NULL;
/* Create an entry id, based upon the hostname and port */
entry_id = create_hostcache_id(hostname, port);
/* If we can't create the entry id, fail */
if(!entry_id)
return rc;
entry_len = strlen(entry_id);
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
/* See if its already in our dns cache */
dns = Curl_hash_pick(data->dns.hostcache, entry_id, entry_len+1);
/* free the allocated entry_id again */
free(entry_id);
/* See whether the returned entry is stale. Done before we release lock */
if( remove_entry_if_stale(data, dns) )
dns = NULL; /* the memory deallocation is being handled by the hash */
if(dns) {
dns->inuse++; /* we use it! */
rc = CURLRESOLV_RESOLVED;
}
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
if(!dns) {
/* The entry was not in the cache. Resolve it to IP address */
Curl_addrinfo *addr;
int respwait;
/* Check what IP specifics the app has requested and if we can provide it.
* If not, bail out. */
if(!Curl_ipvalid(conn))
return CURLRESOLV_ERROR;
/* If Curl_getaddrinfo() returns NULL, 'respwait' might be set to a
non-zero value indicating that we need to wait for the response to the
resolve call */
addr = Curl_getaddrinfo(conn,
#ifdef DEBUGBUILD
(data->set.str[STRING_DEVICE]
&& !strcmp(data->set.str[STRING_DEVICE],
"LocalHost"))?"localhost":
#endif
hostname, port, &respwait);
if(!addr) {
if(respwait) {
/* the response to our resolve call will come asynchronously at
a later time, good or bad */
/* First, check that we haven't received the info by now */
result = Curl_is_resolved(conn, &dns);
if(result) /* error detected */
return CURLRESOLV_ERROR;
if(dns)
rc = CURLRESOLV_RESOLVED; /* pointer provided */
else
rc = CURLRESOLV_PENDING; /* no info yet */
}
}
else {
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
/* we got a response, store it in the cache */
dns = Curl_cache_addr(data, addr, hostname, port);
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
if(!dns)
/* returned failure, bail out nicely */
Curl_freeaddrinfo(addr);
else
rc = CURLRESOLV_RESOLVED;
}
}
*entry = dns;
return rc;
}
CURLcode Curl_loadhostpairs(struct SessionHandle *data)
{
struct curl_slist *hostp;
char hostname[256];
char address[256];
int port;
for(hostp = data->change.resolve; hostp; hostp = hostp->next) {
if(!hostp->data)
continue;
if(hostp->data[0] == '-') {
char *entry_id;
size_t entry_len;
if(2 != sscanf(hostp->data + 1, "%255[^:]:%d", hostname, &port)) {
infof(data, "Couldn't parse CURLOPT_RESOLVE removal entry '%s'!\n",
hostp->data);
continue;
}
/* Create an entry id, based upon the hostname and port */
entry_id = create_hostcache_id(hostname, port);
/* If we can't create the entry id, fail */
if(!entry_id) {
return CURLE_OUT_OF_MEMORY;
}
entry_len = strlen(entry_id);
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
/* delete entry, ignore if it didn't exist */
Curl_hash_delete(data->dns.hostcache, entry_id, entry_len+1);
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
/* free the allocated entry_id again */
free(entry_id);
}
else {
struct Curl_dns_entry *dns;
Curl_addrinfo *addr;
char *entry_id;
size_t entry_len;
if(3 != sscanf(hostp->data, "%255[^:]:%d:%255s", hostname, &port,
address)) {
infof(data, "Couldn't parse CURLOPT_RESOLVE entry '%s'!\n",
hostp->data);
continue;
}
addr = Curl_str2addr(address, port);
if(!addr) {
infof(data, "Address in '%s' found illegal!\n", hostp->data);
continue;
}
/* Create an entry id, based upon the hostname and port */
entry_id = create_hostcache_id(hostname, port);
/* If we can't create the entry id, fail */
if(!entry_id) {
Curl_freeaddrinfo(addr);
return CURLE_OUT_OF_MEMORY;
}
entry_len = strlen(entry_id);
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
/* See if its already in our dns cache */
dns = Curl_hash_pick(data->dns.hostcache, entry_id, entry_len+1);
/* free the allocated entry_id again */
free(entry_id);
if(!dns) {
/* if not in the cache already, put this host in the cache */
dns = Curl_cache_addr(data, addr, hostname, port);
if(dns) {
dns->timestamp = 0; /* mark as added by CURLOPT_RESOLVE */
/* release the returned reference; the cache itself will keep the
* entry alive: */
dns->inuse--;
}
}
else
/* this is a duplicate, free it again */
Curl_freeaddrinfo(addr);
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
if(!dns) {
Curl_freeaddrinfo(addr);
return CURLE_OUT_OF_MEMORY;
}
infof(data, "Added %s:%d:%s to DNS cache\n",
hostname, port, address);
}
}
data->change.resolve = NULL; /* dealt with now */
return CURLE_OK;
}
int Curl_resolv(struct connectdata *conn,
const char *hostname,
int port,
struct Curl_dns_entry **entry)
{
struct Curl_dns_entry *dns = NULL;
struct SessionHandle *data = conn->data;
CURLcode result;
int rc = CURLRESOLV_ERROR; /* default to failure */
*entry = NULL;
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
dns = fetch_addr(conn, hostname, port);
if(dns) {
infof(data, "Hostname %s was found in DNS cache\n", hostname);
dns->inuse++; /* we use it! */
rc = CURLRESOLV_RESOLVED;
}
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
if(!dns) {
/* The entry was not in the cache. Resolve it to IP address */
Curl_addrinfo *addr;
int respwait;
/* Check what IP specifics the app has requested and if we can provide it.
* If not, bail out. */
if(!Curl_ipvalid(conn))
return CURLRESOLV_ERROR;
/* If Curl_getaddrinfo() returns NULL, 'respwait' might be set to a
non-zero value indicating that we need to wait for the response to the
resolve call */
addr = Curl_getaddrinfo(conn,
#ifdef DEBUGBUILD
(data->set.str[STRING_DEVICE]
&& !strcmp(data->set.str[STRING_DEVICE],
"LocalHost"))?"localhost":
#endif
hostname, port, &respwait);
if(!addr) {
if(respwait) {
/* the response to our resolve call will come asynchronously at
a later time, good or bad */
/* First, check that we haven't received the info by now */
result = Curl_resolver_is_resolved(conn, &dns);
if(result) /* error detected */
return CURLRESOLV_ERROR;
if(dns)
rc = CURLRESOLV_RESOLVED; /* pointer provided */
else
rc = CURLRESOLV_PENDING; /* no info yet */
}
}
else {
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
/* we got a response, store it in the cache */
dns = Curl_cache_addr(data, addr, hostname, port);
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
if(!dns)
/* returned failure, bail out nicely */
Curl_freeaddrinfo(addr);
else
rc = CURLRESOLV_RESOLVED;
}
}
*entry = dns;
return rc;
}
CURLcode Curl_loadhostpairs(struct SessionHandle *data)
{
struct curl_slist *hostp;
char hostname[256];
char address[256];
int port;
for(hostp = data->change.resolve; hostp; hostp = hostp->next ) {
if(!hostp->data)
continue;
if(hostp->data[0] == '-') {
/* TODO: mark an entry for removal */
}
else if(3 == sscanf(hostp->data, "%255[^:]:%d:%255s", hostname, &port,
address)) {
struct Curl_dns_entry *dns;
Curl_addrinfo *addr;
char *entry_id;
size_t entry_len;
addr = Curl_str2addr(address, port);
if(!addr) {
infof(data, "Resolve %s found illegal!\n", hostp->data);
continue;
}
/* Create an entry id, based upon the hostname and port */
entry_id = create_hostcache_id(hostname, port);
/* If we can't create the entry id, fail */
if(!entry_id) {
Curl_freeaddrinfo(addr);
return CURLE_OUT_OF_MEMORY;
}
entry_len = strlen(entry_id);
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
/* See if its already in our dns cache */
dns = Curl_hash_pick(data->dns.hostcache, entry_id, entry_len+1);
/* free the allocated entry_id again */
free(entry_id);
if(!dns)
/* if not in the cache already, put this host in the cache */
dns = Curl_cache_addr(data, addr, hostname, port);
else
/* this is a duplicate, free it again */
Curl_freeaddrinfo(addr);
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
if(!dns) {
Curl_freeaddrinfo(addr);
return CURLE_OUT_OF_MEMORY;
}
infof(data, "Added %s:%d:%s to DNS cache\n",
hostname, port, address);
}
}
data->change.resolve = NULL; /* dealt with now */
return CURLE_OK;
}
Curl_addrinfo *
Curl_he2ai(const struct hostent *he, int port)
{
Curl_addrinfo *ai;
Curl_addrinfo *prevai = NULL;
Curl_addrinfo *firstai = NULL;
struct sockaddr_in *addr;
#ifdef ENABLE_IPV6
struct sockaddr_in6 *addr6;
#endif
CURLcode result = CURLE_OK;
int i;
char *curr;
if(!he)
/* no input == no output! */
return NULL;
DEBUGASSERT((he->h_name != NULL) && (he->h_addr_list != NULL));
for(i=0; (curr = he->h_addr_list[i]) != NULL; i++) {
size_t ss_size;
#ifdef ENABLE_IPV6
if(he->h_addrtype == AF_INET6)
ss_size = sizeof (struct sockaddr_in6);
else
#endif
ss_size = sizeof (struct sockaddr_in);
if((ai = calloc(1, sizeof(Curl_addrinfo))) == NULL) {
result = CURLE_OUT_OF_MEMORY;
break;
}
if((ai->ai_canonname = strdup(he->h_name)) == NULL) {
result = CURLE_OUT_OF_MEMORY;
free(ai);
break;
}
if((ai->ai_addr = calloc(1, ss_size)) == NULL) {
result = CURLE_OUT_OF_MEMORY;
free(ai->ai_canonname);
free(ai);
break;
}
if(!firstai)
/* store the pointer we want to return from this function */
firstai = ai;
if(prevai)
/* make the previous entry point to this */
prevai->ai_next = ai;
ai->ai_family = he->h_addrtype;
/* we return all names as STREAM, so when using this address for TFTP
the type must be ignored and conn->socktype be used instead! */
ai->ai_socktype = SOCK_STREAM;
ai->ai_addrlen = (curl_socklen_t)ss_size;
/* leave the rest of the struct filled with zero */
switch (ai->ai_family) {
case AF_INET:
addr = (void *)ai->ai_addr; /* storage area for this info */
memcpy(&addr->sin_addr, curr, sizeof(struct in_addr));
addr->sin_family = (unsigned short)(he->h_addrtype);
addr->sin_port = htons((unsigned short)port);
break;
#ifdef ENABLE_IPV6
case AF_INET6:
addr6 = (void *)ai->ai_addr; /* storage area for this info */
memcpy(&addr6->sin6_addr, curr, sizeof(struct in6_addr));
addr6->sin6_family = (unsigned short)(he->h_addrtype);
addr6->sin6_port = htons((unsigned short)port);
break;
#endif
}
prevai = ai;
}
if(result != CURLE_OK) {
Curl_freeaddrinfo(firstai);
firstai = NULL;
}
return firstai;
}
int
Curl_getaddrinfo_ex(const char *nodename,
const char *servname,
const struct addrinfo *hints,
Curl_addrinfo **result)
{
const struct addrinfo *ai;
struct addrinfo *aihead;
Curl_addrinfo *cafirst = NULL;
Curl_addrinfo *calast = NULL;
Curl_addrinfo *ca;
size_t ss_size;
int error;
*result = NULL; /* assume failure */
error = getaddrinfo(nodename, servname, hints, &aihead);
if(error)
return error;
/* traverse the addrinfo list */
for(ai = aihead; ai != NULL; ai = ai->ai_next) {
/* ignore elements with unsupported address family, */
/* settle family-specific sockaddr structure size. */
if(ai->ai_family == AF_INET)
ss_size = sizeof(struct sockaddr_in);
#ifdef ENABLE_IPV6
else if(ai->ai_family == AF_INET6)
ss_size = sizeof(struct sockaddr_in6);
#endif
else
continue;
/* ignore elements without required address info */
if((ai->ai_addr == NULL) || !(ai->ai_addrlen > 0))
continue;
/* ignore elements with bogus address size */
if((size_t)ai->ai_addrlen < ss_size)
continue;
if((ca = malloc(sizeof(Curl_addrinfo))) == NULL) {
error = EAI_MEMORY;
break;
}
/* copy each structure member individually, member ordering, */
/* size, or padding might be different for each platform. */
ca->ai_flags = ai->ai_flags;
ca->ai_family = ai->ai_family;
ca->ai_socktype = ai->ai_socktype;
ca->ai_protocol = ai->ai_protocol;
ca->ai_addrlen = (curl_socklen_t)ss_size;
ca->ai_addr = NULL;
ca->ai_canonname = NULL;
ca->ai_next = NULL;
if((ca->ai_addr = malloc(ss_size)) == NULL) {
error = EAI_MEMORY;
free(ca);
break;
}
memcpy(ca->ai_addr, ai->ai_addr, ss_size);
if(ai->ai_canonname != NULL) {
if((ca->ai_canonname = strdup(ai->ai_canonname)) == NULL) {
error = EAI_MEMORY;
free(ca->ai_addr);
free(ca);
break;
}
}
/* if the return list is empty, this becomes the first element */
if(!cafirst)
cafirst = ca;
/* add this element last in the return list */
if(calast)
calast->ai_next = ca;
calast = ca;
}
/* destroy the addrinfo list */
if(aihead)
freeaddrinfo(aihead);
/* if we failed, also destroy the Curl_addrinfo list */
if(error) {
Curl_freeaddrinfo(cafirst);
cafirst = NULL;
}
else if(!cafirst) {
#ifdef EAI_NONAME
/* rfc3493 conformant */
error = EAI_NONAME;
#else
/* rfc3493 obsoleted */
error = EAI_NODATA;
#endif
#ifdef USE_WINSOCK
SET_SOCKERRNO(error);
#endif
}
*result = cafirst;
/* This is not a CURLcode */
return error;
}
int Curl_resolv(struct connectdata *conn,
const char *hostname,
int port,
struct Curl_dns_entry **entry)
{
char *entry_id = NULL;
struct Curl_dns_entry *dns = NULL;
size_t entry_len;
int wait;
struct SessionHandle *data = conn->data;
CURLcode result;
int rc;
*entry = NULL;
#ifdef HAVE_SIGSETJMP
/* this allows us to time-out from the name resolver, as the timeout
will generate a signal and we will siglongjmp() from that here */
if(!data->set.no_signal) {
if (sigsetjmp(curl_jmpenv, 1)) {
/* this is coming from a siglongjmp() */
failf(data, "name lookup timed out");
return CURLRESOLV_ERROR;
}
}
#endif
/* Create an entry id, based upon the hostname and port */
entry_id = create_hostcache_id(hostname, port);
/* If we can't create the entry id, fail */
if (!entry_id)
return CURLRESOLV_ERROR;
entry_len = strlen(entry_id);
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
/* See if its already in our dns cache */
dns = Curl_hash_pick(data->dns.hostcache, entry_id, entry_len+1);
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
/* free the allocated entry_id again */
free(entry_id);
/* See whether the returned entry is stale. Deliberately done after the
locked block */
if ( remove_entry_if_stale(data,dns) )
dns = NULL; /* the memory deallocation is being handled by the hash */
rc = CURLRESOLV_ERROR; /* default to failure */
if (!dns) {
/* The entry was not in the cache. Resolve it to IP address */
Curl_addrinfo *addr;
/* Check what IP specifics the app has requested and if we can provide it.
* If not, bail out. */
if(!Curl_ipvalid(data))
return CURLRESOLV_ERROR;
/* If Curl_getaddrinfo() returns NULL, 'wait' might be set to a non-zero
value indicating that we need to wait for the response to the resolve
call */
addr = Curl_getaddrinfo(conn, hostname, port, &wait);
if (!addr) {
if(wait) {
/* the response to our resolve call will come asynchronously at
a later time, good or bad */
/* First, check that we haven't received the info by now */
result = Curl_is_resolved(conn, &dns);
if(result) /* error detected */
return CURLRESOLV_ERROR;
if(dns)
rc = CURLRESOLV_RESOLVED; /* pointer provided */
else
rc = CURLRESOLV_PENDING; /* no info yet */
}
}
else {
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
/* we got a response, store it in the cache */
dns = Curl_cache_addr(data, addr, hostname, port);
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
if(!dns)
/* returned failure, bail out nicely */
Curl_freeaddrinfo(addr);
else
rc = CURLRESOLV_RESOLVED;
}
}
else {
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
dns->inuse++; /* we use it! */
if(data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
rc = CURLRESOLV_RESOLVED;
}
*entry = dns;
return rc;
}
