summaryrefslogtreecommitdiff
path: root/lib/asyn-ares.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/asyn-ares.c')
-rw-r--r--lib/asyn-ares.c639
1 files changed, 639 insertions, 0 deletions
diff --git a/lib/asyn-ares.c b/lib/asyn-ares.c
new file mode 100644
index 000000000..44d00bdb0
--- /dev/null
+++ b/lib/asyn-ares.c
@@ -0,0 +1,639 @@
+/***************************************************************************
+ * _ _ ____ _
+ * Project ___| | | | _ \| |
+ * / __| | | | |_) | |
+ * | (__| |_| | _ <| |___
+ * \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2012, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at http://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+
+#include "setup.h"
+
+#ifdef HAVE_LIMITS_H
+#include <limits.h>
+#endif
+#ifdef HAVE_NETINET_IN_H
+#include <netinet/in.h>
+#endif
+#ifdef HAVE_NETDB_H
+#include <netdb.h>
+#endif
+#ifdef HAVE_ARPA_INET_H
+#include <arpa/inet.h>
+#endif
+#ifdef __VMS
+#include <in.h>
+#include <inet.h>
+#endif
+
+#ifdef HAVE_PROCESS_H
+#include <process.h>
+#endif
+
+#if (defined(NETWARE) && defined(__NOVELL_LIBC__))
+#undef in_addr_t
+#define in_addr_t unsigned long
+#endif
+
+/***********************************************************************
+ * Only for ares-enabled builds
+ * And only for functions that fulfill the asynch resolver backend API
+ * as defined in asyn.h, nothing else belongs in this file!
+ **********************************************************************/
+
+#ifdef CURLRES_ARES
+
+#include "urldata.h"
+#include "sendf.h"
+#include "hostip.h"
+#include "hash.h"
+#include "share.h"
+#include "strerror.h"
+#include "url.h"
+#include "multiif.h"
+#include "inet_pton.h"
+#include "connect.h"
+#include "select.h"
+#include "progress.h"
+
+#define _MPRINTF_REPLACE /* use our functions only */
+#include <curl/mprintf.h>
+
+# if defined(CURL_STATICLIB) && !defined(CARES_STATICLIB) && \
+ (defined(WIN32) || defined(_WIN32) || defined(__SYMBIAN32__))
+# define CARES_STATICLIB
+# endif
+# include <ares.h>
+# include <ares_version.h> /* really old c-ares didn't include this by
+ itself */
+
+#if ARES_VERSION >= 0x010500
+/* c-ares 1.5.0 or later, the callback proto is modified */
+#define HAVE_CARES_CALLBACK_TIMEOUTS 1
+#endif
+
+#include "curl_memory.h"
+/* The last #include file should be: */
+#include "memdebug.h"
+
+struct ResolverResults {
+ int num_pending; /* number of ares_gethostbyname() requests */
+ Curl_addrinfo *temp_ai; /* intermediary result while fetching c-ares parts */
+ int last_status;
+};
+
+/*
+ * Curl_resolver_global_init() - the generic low-level asynchronous name
+ * resolve API. Called from curl_global_init() to initialize global resolver
+ * environment. Initializes ares library.
+ */
+int Curl_resolver_global_init(void)
+{
+#ifdef CARES_HAVE_ARES_LIBRARY_INIT
+ if(ares_library_init(ARES_LIB_INIT_ALL)) {
+ return CURLE_FAILED_INIT;
+ }
+#endif
+ return CURLE_OK;
+}
+
+/*
+ * Curl_resolver_global_cleanup()
+ *
+ * Called from curl_global_cleanup() to destroy global resolver environment.
+ * Deinitializes ares library.
+ */
+void Curl_resolver_global_cleanup(void)
+{
+#ifdef CARES_HAVE_ARES_LIBRARY_CLEANUP
+ ares_library_cleanup();
+#endif
+}
+
+/*
+ * Curl_resolver_init()
+ *
+ * Called from curl_easy_init() -> Curl_open() to initialize resolver
+ * URL-state specific environment ('resolver' member of the UrlState
+ * structure). Fills the passed pointer by the initialized ares_channel.
+ */
+CURLcode Curl_resolver_init(void **resolver)
+{
+ int status = ares_init((ares_channel*)resolver);
+ if(status != ARES_SUCCESS) {
+ if(status == ARES_ENOMEM)
+ return CURLE_OUT_OF_MEMORY;
+ else
+ return CURLE_FAILED_INIT;
+ }
+ return CURLE_OK;
+ /* make sure that all other returns from this function should destroy the
+ ares channel before returning error! */
+}
+
+/*
+ * Curl_resolver_cleanup()
+ *
+ * Called from curl_easy_cleanup() -> Curl_close() to cleanup resolver
+ * URL-state specific environment ('resolver' member of the UrlState
+ * structure). Destroys the ares channel.
+ */
+void Curl_resolver_cleanup(void *resolver)
+{
+ ares_destroy((ares_channel)resolver);
+}
+
+/*
+ * Curl_resolver_duphandle()
+ *
+ * Called from curl_easy_duphandle() to duplicate resolver URL-state specific
+ * environment ('resolver' member of the UrlState structure). Duplicates the
+ * 'from' ares channel and passes the resulting channel to the 'to' pointer.
+ */
+int Curl_resolver_duphandle(void **to, void *from)
+{
+ /* Clone the ares channel for the new handle */
+ if(ARES_SUCCESS != ares_dup((ares_channel*)to,(ares_channel)from))
+ return CURLE_FAILED_INIT;
+ return CURLE_OK;
+}
+
+static void destroy_async_data (struct Curl_async *async);
+
+/*
+ * Cancel all possibly still on-going resolves for this connection.
+ */
+void Curl_resolver_cancel(struct connectdata *conn)
+{
+ if(conn && conn->data && conn->data->state.resolver)
+ ares_cancel((ares_channel)conn->data->state.resolver);
+ destroy_async_data(&conn->async);
+}
+
+/*
+ * destroy_async_data() cleans up async resolver data.
+ */
+static void destroy_async_data (struct Curl_async *async)
+{
+ if(async->hostname)
+ 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_resolver_fdset() is called when someone from the outside world (using
+ * curl_multi_fdset()) wants to get our fd_set setup and we're talking with
+ * ares. The caller must make sure that this function is only called when we
+ * have a working ares channel.
+ *
+ * Returns: CURLE_OK always!
+ */
+
+int Curl_resolver_getsock(struct connectdata *conn,
+ curl_socket_t *socks,
+ int numsocks)
+
+{
+ struct timeval maxtime;
+ struct timeval timebuf;
+ struct timeval *timeout;
+ long milli;
+ int max = ares_getsock((ares_channel)conn->data->state.resolver,
+ (ares_socket_t *)socks, numsocks);
+
+ maxtime.tv_sec = CURL_TIMEOUT_RESOLVE;
+ maxtime.tv_usec = 0;
+
+ timeout = ares_timeout((ares_channel)conn->data->state.resolver, &maxtime,
+ &timebuf);
+ milli = (timeout->tv_sec * 1000) + (timeout->tv_usec/1000);
+ if(milli == 0)
+ milli += 10;
+ Curl_expire(conn->data, milli);
+
+ return max;
+}
+
+/*
+ * waitperform()
+ *
+ * 1) Ask ares what sockets it currently plays with, then
+ * 2) wait for the timeout period to check for action on ares' sockets.
+ * 3) tell ares to act on all the sockets marked as "with action"
+ *
+ * return number of sockets it worked on
+ */
+
+static int waitperform(struct connectdata *conn, int timeout_ms)
+{
+ struct SessionHandle *data = conn->data;
+ int nfds;
+ int bitmask;
+ ares_socket_t socks[ARES_GETSOCK_MAXNUM];
+ struct pollfd pfd[ARES_GETSOCK_MAXNUM];
+ int i;
+ int num = 0;
+
+ bitmask = ares_getsock((ares_channel)data->state.resolver, socks,
+ ARES_GETSOCK_MAXNUM);
+
+ for(i=0; i < ARES_GETSOCK_MAXNUM; i++) {
+ pfd[i].events = 0;
+ pfd[i].revents = 0;
+ if(ARES_GETSOCK_READABLE(bitmask, i)) {
+ pfd[i].fd = socks[i];
+ pfd[i].events |= POLLRDNORM|POLLIN;
+ }
+ if(ARES_GETSOCK_WRITABLE(bitmask, i)) {
+ pfd[i].fd = socks[i];
+ pfd[i].events |= POLLWRNORM|POLLOUT;
+ }
+ if(pfd[i].events != 0)
+ num++;
+ else
+ break;
+ }
+
+ if(num)
+ nfds = Curl_poll(pfd, num, timeout_ms);
+ else
+ nfds = 0;
+
+ if(!nfds)
+ /* Call ares_process() unconditonally here, even if we simply timed out
+ above, as otherwise the ares name resolve won't timeout! */
+ ares_process_fd((ares_channel)data->state.resolver, ARES_SOCKET_BAD,
+ ARES_SOCKET_BAD);
+ else {
+ /* move through the descriptors and ask for processing on them */
+ for(i=0; i < num; i++)
+ ares_process_fd((ares_channel)data->state.resolver,
+ pfd[i].revents & (POLLRDNORM|POLLIN)?
+ pfd[i].fd:ARES_SOCKET_BAD,
+ pfd[i].revents & (POLLWRNORM|POLLOUT)?
+ pfd[i].fd:ARES_SOCKET_BAD);
+ }
+ return nfds;
+}
+
+/*
+ * Curl_resolver_is_resolved() is called repeatedly to check if a previous
+ * name resolve request has completed. It should also make sure to time-out if
+ * the operation seems to take too long.
+ *
+ * Returns normal CURLcode errors.
+ */
+CURLcode Curl_resolver_is_resolved(struct connectdata *conn,
+ struct Curl_dns_entry **dns)
+{
+ struct SessionHandle *data = conn->data;
+ struct ResolverResults *res = (struct ResolverResults *)
+ conn->async.os_specific;
+
+ *dns = NULL;
+
+ waitperform(conn, 0);
+
+ if(res && !res->num_pending) {
+ (void)Curl_addrinfo_callback(conn, res->last_status, res->temp_ai);
+ /* temp_ai ownership is moved to the connection, so we need not free-up
+ them */
+ res->temp_ai = NULL;
+ destroy_async_data(&conn->async);
+ if(!conn->async.dns) {
+ failf(data, "Could not resolve %s: %s (%s)",
+ conn->bits.proxy?"proxy":"host",
+ conn->host.dispname,
+ ares_strerror(conn->async.status));
+ return conn->bits.proxy?CURLE_COULDNT_RESOLVE_PROXY:
+ CURLE_COULDNT_RESOLVE_HOST;
+ }
+ *dns = conn->async.dns;
+ }
+
+ return CURLE_OK;
+}
+
+/*
+ * Curl_resolver_wait_resolv()
+ *
+ * waits for a resolve to finish. This function should be avoided since using
+ * this risk getting the multi interface to "hang".
+ *
+ * If 'entry' is non-NULL, make it point to the resolved dns entry
+ *
+ * Returns CURLE_COULDNT_RESOLVE_HOST if the host was not resolved, and
+ * CURLE_OPERATION_TIMEDOUT if a time-out occurred.
+ */
+CURLcode Curl_resolver_wait_resolv(struct connectdata *conn,
+ struct Curl_dns_entry **entry)
+{
+ CURLcode rc=CURLE_OK;
+ struct SessionHandle *data = conn->data;
+ long timeout;
+ struct timeval now = Curl_tvnow();
+ struct Curl_dns_entry *temp_entry;
+
+ timeout = Curl_timeleft(data, &now, TRUE);
+ if(!timeout)
+ timeout = CURL_TIMEOUT_RESOLVE * 1000; /* default name resolve timeout */
+
+ /* Wait for the name resolve query to complete. */
+ for(;;) {
+ struct timeval *tvp, tv, store;
+ long timediff;
+ int itimeout;
+ int timeout_ms;
+
+ itimeout = (timeout > (long)INT_MAX) ? INT_MAX : (int)timeout;
+
+ store.tv_sec = itimeout/1000;
+ store.tv_usec = (itimeout%1000)*1000;
+
+ tvp = ares_timeout((ares_channel)data->state.resolver, &store, &tv);
+
+ /* use the timeout period ares returned to us above if less than one
+ second is left, otherwise just use 1000ms to make sure the progress
+ callback gets called frequent enough */
+ if(!tvp->tv_sec)
+ timeout_ms = (int)(tvp->tv_usec/1000);
+ else
+ timeout_ms = 1000;
+
+ waitperform(conn, timeout_ms);
+ Curl_resolver_is_resolved(conn,&temp_entry);
+
+ if(conn->async.done)
+ break;
+
+ if(Curl_pgrsUpdate(conn)) {
+ rc = CURLE_ABORTED_BY_CALLBACK;
+ timeout = -1; /* trigger the cancel below */
+ }
+ else {
+ struct timeval now2 = Curl_tvnow();
+ timediff = Curl_tvdiff(now2, now); /* spent time */
+ timeout -= timediff?timediff:1; /* always deduct at least 1 */
+ now = now2; /* for next loop */
+ }
+ if(timeout < 0) {
+ /* our timeout, so we cancel the ares operation */
+ ares_cancel((ares_channel)data->state.resolver);
+ break;
+ }
+ }
+
+ /* Operation complete, if the lookup was successful we now have the entry
+ in the cache. */
+
+ if(entry)
+ *entry = conn->async.dns;
+
+ if(!conn->async.dns) {
+ /* a name was not resolved */
+ if((timeout < 0) || (conn->async.status == ARES_ETIMEOUT)) {
+ if(conn->bits.proxy) {
+ failf(data, "Resolving proxy timed out: %s", conn->proxy.dispname);
+ rc = CURLE_COULDNT_RESOLVE_PROXY;
+ }
+ else {
+ failf(data, "Resolving host timed out: %s", conn->host.dispname);
+ rc = CURLE_COULDNT_RESOLVE_HOST;
+ }
+ }
+ else if(conn->async.done) {
+ if(conn->bits.proxy) {
+ failf(data, "Could not resolve proxy: %s (%s)", conn->proxy.dispname,
+ ares_strerror(conn->async.status));
+ rc = CURLE_COULDNT_RESOLVE_PROXY;
+ }
+ else {
+ failf(data, "Could not resolve host: %s (%s)", conn->host.dispname,
+ ares_strerror(conn->async.status));
+ rc = CURLE_COULDNT_RESOLVE_HOST;
+ }
+ }
+ else
+ rc = CURLE_OPERATION_TIMEDOUT;
+
+ /* close the connection, since we can't return failure here without
+ cleaning up this connection properly */
+ conn->bits.close = TRUE;
+ }
+
+ return rc;
+}
+
+/* Connects results to the list */
+static void compound_results(struct ResolverResults *res,
+ Curl_addrinfo *ai)
+{
+ Curl_addrinfo *ai_tail;
+ if(!ai)
+ return;
+ ai_tail = ai;
+
+ while(ai_tail->ai_next)
+ ai_tail = ai_tail->ai_next;
+
+ /* Add the new results to the list of old results. */
+ ai_tail->ai_next = res->temp_ai;
+ res->temp_ai = ai;
+}
+
+/*
+ * ares_query_completed_cb() is the callback that ares will call when
+ * the host query initiated by ares_gethostbyname() from Curl_getaddrinfo(),
+ * when using ares, is completed either successfully or with failure.
+ */
+static void query_completed_cb(void *arg, /* (struct connectdata *) */
+ int status,
+#ifdef HAVE_CARES_CALLBACK_TIMEOUTS
+ int timeouts,
+#endif
+ struct hostent *hostent)
+{
+ struct connectdata *conn = (struct connectdata *)arg;
+ struct ResolverResults *res;
+
+#ifdef HAVE_CARES_CALLBACK_TIMEOUTS
+ (void)timeouts; /* ignored */
+#endif
+
+ if(ARES_EDESTRUCTION == status)
+ /* when this ares handle is getting destroyed, the 'arg' pointer may not
+ be valid so only defer it when we know the 'status' says its fine! */
+ return;
+
+ res = (struct ResolverResults *)conn->async.os_specific;
+ res->num_pending--;
+
+ if(CURL_ASYNC_SUCCESS == status) {
+ Curl_addrinfo *ai = Curl_he2ai(hostent, conn->async.port);
+ if(ai) {
+ compound_results(res, ai);
+ }
+ }
+ /* A successful result overwrites any previous error */
+ if(res->last_status != ARES_SUCCESS)
+ res->last_status = status;
+}
+
+/*
+ * Curl_resolver_getaddrinfo() - when using ares
+ *
+ * Returns name information about the given hostname and port number. If
+ * successful, the 'hostent' is returned and the forth argument will point to
+ * memory we need to free after use. That memory *MUST* be freed with
+ * Curl_freeaddrinfo(), nothing else.
+ */
+Curl_addrinfo *Curl_resolver_getaddrinfo(struct connectdata *conn,
+ const char *hostname,
+ int port,
+ int *waitp)
+{
+ char *bufp;
+ struct SessionHandle *data = conn->data;
+ struct in_addr in;
+ int family = PF_INET;
+#ifdef ENABLE_IPV6 /* CURLRES_IPV6 */
+ struct in6_addr in6;
+#endif /* CURLRES_IPV6 */
+
+ *waitp = 0; /* default to synchronous response */
+
+ /* First check if this is an IPv4 address string */
+ if(Curl_inet_pton(AF_INET, hostname, &in) > 0) {
+ /* This is a dotted IP address 123.123.123.123-style */
+ return Curl_ip2addr(AF_INET, &in, hostname, port);
+ }
+
+#ifdef ENABLE_IPV6 /* CURLRES_IPV6 */
+ /* Otherwise, check if this is an IPv6 address string */
+ if(Curl_inet_pton (AF_INET6, hostname, &in6) > 0)
+ /* This must be an IPv6 address literal. */
+ return Curl_ip2addr(AF_INET6, &in6, hostname, port);
+
+ switch(conn->ip_version) {
+ default:
+#if ARES_VERSION >= 0x010601
+ family = PF_UNSPEC; /* supported by c-ares since 1.6.1, so for older
+ c-ares versions this just falls through and defaults
+ to PF_INET */
+ break;
+#endif
+ case CURL_IPRESOLVE_V4:
+ family = PF_INET;
+ break;
+ case CURL_IPRESOLVE_V6:
+ family = PF_INET6;
+ break;
+ }
+#endif /* CURLRES_IPV6 */
+
+ bufp = strdup(hostname);
+ if(bufp) {
+ struct ResolverResults *res = NULL;
+ Curl_safefree(conn->async.hostname);
+ conn->async.hostname = bufp;
+ conn->async.port = port;
+ conn->async.done = FALSE; /* not done */
+ conn->async.status = 0; /* clear */
+ conn->async.dns = NULL; /* clear */
+ res = calloc(sizeof(struct ResolverResults),1);
+ if(!res) {
+ Curl_safefree(conn->async.hostname);
+ conn->async.hostname = NULL;
+ return NULL;
+ }
+ conn->async.os_specific = res;
+
+ /* initial status - failed */
+ res->last_status = ARES_ENOTFOUND;
+#ifdef ENABLE_IPV6 /* CURLRES_IPV6 */
+ if(family == PF_UNSPEC) {
+ if(Curl_ipv6works()) {
+ res->num_pending = 2;
+
+ /* areschannel is already setup in the Curl_open() function */
+ ares_gethostbyname((ares_channel)data->state.resolver, hostname,
+ PF_INET, query_completed_cb, conn);
+ ares_gethostbyname((ares_channel)data->state.resolver, hostname,
+ PF_INET6, query_completed_cb, conn);
+ }
+ else {
+ res->num_pending = 1;
+
+ /* areschannel is already setup in the Curl_open() function */
+ ares_gethostbyname((ares_channel)data->state.resolver, hostname,
+ PF_INET, query_completed_cb, conn);
+ }
+ }
+ else
+#endif /* CURLRES_IPV6 */
+ {
+ res->num_pending = 1;
+
+ /* areschannel is already setup in the Curl_open() function */
+ ares_gethostbyname((ares_channel)data->state.resolver, hostname, family,
+ query_completed_cb, conn);
+ }
+
+ *waitp = 1; /* expect asynchronous response */
+ }
+ return NULL; /* no struct yet */
+}
+
+CURLcode Curl_set_dns_servers(struct SessionHandle *data,
+ char *servers)
+{
+ CURLcode result = CURLE_NOT_BUILT_IN;
+#if (ARES_VERSION >= 0x010704)
+ int ares_result = ares_set_servers_csv(data->state.resolver, servers);
+ switch(ares_result) {
+ case ARES_SUCCESS:
+ result = CURLE_OK;
+ break;
+ case ARES_ENOMEM:
+ result = CURLE_OUT_OF_MEMORY;
+ break;
+ case ARES_ENOTINITIALIZED:
+ case ARES_ENODATA:
+ case ARES_EBADSTR:
+ default:
+ result = CURLE_BAD_FUNCTION_ARGUMENT;
+ break;
+ }
+#else /* too old c-ares version! */
+ (void)data;
+ (void)servers;
+#endif
+ return result;
+}
+#endif /* CURLRES_ARES */