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authorArne Schwabe <arne@rfc2549.org>2012-08-07 12:03:57 +0200
committerDavid Sommerseth <davids@redhat.com>2012-09-02 21:18:43 +0200
commitf2d6f3bc06db4f9e0815fc25e35e393f794c193a (patch)
tree3ba404041bb2c68bc2d9225deff0ec8949bd2df2
parent3630a7a50099874d55bf8e212ad4a97d6e70966f (diff)
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Merge getaddr_multi and getaddr6 into one function
the getaddr6 and getaddr_mutli functions are duplicates of each other. Since we always require getaddrinfo to be present both function are merge into one openvpn_getaddrinfo. This functions also returns a standard struct addrinfo* so our resolve interface is closer to the standard unix interface. The getaddr function is a wrapper which provides backward compatibility for IPv4 addresses. Ipv6 calls and calls to getaddr_multi are replaced with the new interface. Signed-off-by: Arne Schwabe <arne@rfc2549.org> Acked-by: Gert Doering <gert@greenie.muc.de> Message-Id: 1344333837-22076-1-git-send-email-arne@rfc2549.org URL: http://article.gmane.org/gmane.network.openvpn.devel/6959 Signed-off-by: David Sommerseth <davids@redhat.com> [DS: Applied proper indenting on the changes wherever needed]
-rw-r--r--src/openvpn/route.c45
-rw-r--r--src/openvpn/socket.c495
-rw-r--r--src/openvpn/socket.h17
3 files changed, 166 insertions, 391 deletions
diff --git a/src/openvpn/route.c b/src/openvpn/route.c
index d967d4f..8c3d0dc 100644
--- a/src/openvpn/route.c
+++ b/src/openvpn/route.c
@@ -268,12 +268,14 @@ is_special_addr (const char *addr_str)
static bool
init_route (struct route *r,
- struct resolve_list *network_list,
+ struct addrinfo **network_list,
const struct route_option *ro,
const struct route_list *rl)
{
const in_addr_t default_netmask = IPV4_NETMASK_HOST;
bool status;
+ int ret;
+ struct in_addr special;
CLEAR (*r);
r->option = ro;
@@ -284,19 +286,22 @@ init_route (struct route *r,
{
goto fail;
}
-
- if (!get_special_addr (rl, ro->network, &r->network, &status))
+
+
+ /* get_special_addr replaces specialaddr with a special ip addr
+ like gw. getaddrinfo is called to convert a a addrinfo struct */
+
+ if(get_special_addr (rl, ro->network, &special.s_addr, &status))
{
- r->network = getaddr_multi (
- GETADDR_RESOLVE
- | GETADDR_HOST_ORDER
- | GETADDR_WARN_ON_SIGNAL,
- ro->network,
- 0,
- &status,
- NULL,
- network_list);
+ special.s_addr = htonl(special.s_addr);
+ ret = openvpn_getaddrinfo(0, inet_ntoa(special), 0, NULL,
+ AF_INET, network_list);
}
+ else
+ ret = openvpn_getaddrinfo(GETADDR_RESOLVE | GETADDR_WARN_ON_SIGNAL,
+ ro->network, 0, NULL, AF_INET, network_list);
+
+ status = (ret == 0);
if (!status)
goto fail;
@@ -642,11 +647,8 @@ init_route_list (struct route_list *rl,
bool warned = false;
for (i = 0; i < opt->n; ++i)
{
- struct resolve_list netlist;
+ struct addrinfo* netlist;
struct route r;
- int k;
-
- CLEAR(netlist); /* init_route() will not always init this */
if (!init_route (&r,
&netlist,
@@ -655,16 +657,12 @@ init_route_list (struct route_list *rl,
ret = false;
else
{
- if (!netlist.len)
- {
- netlist.data[0] = r.network;
- netlist.len = 1;
- }
- for (k = 0; k < netlist.len; ++k)
+ struct addrinfo* curele;
+ for (curele = netlist; curele; curele = curele->ai_next)
{
if (j < rl->capacity)
{
- r.network = netlist.data[k];
+ r.network = ntohl(((struct sockaddr_in*)(curele)->ai_addr)->sin_addr.s_addr);
rl->routes[j++] = r;
}
else
@@ -676,6 +674,7 @@ init_route_list (struct route_list *rl,
}
}
}
+ freeaddrinfo(netlist);
}
}
rl->n = j;
diff --git a/src/openvpn/socket.c b/src/openvpn/socket.c
index a34e78c..505cf3b 100644
--- a/src/openvpn/socket.c
+++ b/src/openvpn/socket.c
@@ -93,220 +93,53 @@ h_errno_msg(int h_errno_err)
*/
in_addr_t
getaddr (unsigned int flags,
- const char *hostname,
- int resolve_retry_seconds,
- bool *succeeded,
- volatile int *signal_received)
+ const char *hostname,
+ int resolve_retry_seconds,
+ bool *succeeded,
+ volatile int *signal_received)
{
- return getaddr_multi (flags, hostname, resolve_retry_seconds, succeeded, signal_received, NULL);
-}
-
-in_addr_t
-getaddr_multi (unsigned int flags,
- const char *hostname,
- int resolve_retry_seconds,
- bool *succeeded,
- volatile int *signal_received,
- struct resolve_list *reslist)
-{
- struct in_addr ia;
+ struct addrinfo *ai;
int status;
- int sigrec = 0;
- int msglevel = (flags & GETADDR_FATAL) ? M_FATAL : D_RESOLVE_ERRORS;
- struct gc_arena gc = gc_new ();
-
- if (reslist)
- reslist->len = 0;
-
- if (flags & GETADDR_RANDOMIZE)
- hostname = hostname_randomize(hostname, &gc);
-
- if (flags & GETADDR_MSG_VIRT_OUT)
- msglevel |= M_MSG_VIRT_OUT;
-
- CLEAR (ia);
- if (succeeded)
- *succeeded = false;
-
- if ((flags & (GETADDR_FATAL_ON_SIGNAL|GETADDR_WARN_ON_SIGNAL))
- && !signal_received)
- signal_received = &sigrec;
-
- status = openvpn_inet_aton (hostname, &ia); /* parse ascii IP address */
-
- if (status != OIA_IP) /* parse as IP address failed? */
- {
- const int fail_wait_interval = 5; /* seconds */
- int resolve_retries = (flags & GETADDR_TRY_ONCE) ? 1 : (resolve_retry_seconds / fail_wait_interval);
- struct hostent *h;
- const char *fmt;
- int level = 0;
-
- CLEAR (ia);
-
- fmt = "RESOLVE: Cannot resolve host address: %s: %s";
- if ((flags & GETADDR_MENTION_RESOLVE_RETRY)
- && !resolve_retry_seconds)
- fmt = "RESOLVE: Cannot resolve host address: %s: %s (I would have retried this name query if you had specified the --resolv-retry option.)";
-
- if (!(flags & GETADDR_RESOLVE) || status == OIA_ERROR)
- {
- msg (msglevel, "RESOLVE: Cannot parse IP address: %s", hostname);
- goto done;
- }
-
-#ifdef ENABLE_MANAGEMENT
- if (flags & GETADDR_UPDATE_MANAGEMENT_STATE)
- {
- if (management)
- management_set_state (management,
- OPENVPN_STATE_RESOLVE,
- NULL,
- (in_addr_t)0,
- (in_addr_t)0);
- }
-#endif
-
- /*
- * Resolve hostname
- */
- while (true)
- {
- /* try hostname lookup */
-#if defined(HAVE_RES_INIT)
- res_init ();
-#endif
- h = gethostbyname (hostname);
-
- if (signal_received)
- {
- get_signal (signal_received);
- if (*signal_received) /* were we interrupted by a signal? */
- {
- h = NULL;
- if (*signal_received == SIGUSR1) /* ignore SIGUSR1 */
- {
- msg (level, "RESOLVE: Ignored SIGUSR1 signal received during DNS resolution attempt");
- *signal_received = 0;
- }
- else
- goto done;
- }
- }
-
- /* success? */
- if (h)
- break;
-
- /* resolve lookup failed, should we
- continue or fail? */
-
- level = msglevel;
- if (resolve_retries > 0)
- level = D_RESOLVE_ERRORS;
-
- msg (level,
- fmt,
- hostname,
- h_errno_msg (h_errno));
-
- if (--resolve_retries <= 0)
- goto done;
-
- openvpn_sleep (fail_wait_interval);
- }
-
- if (h->h_addrtype != AF_INET || h->h_length != 4)
- {
- msg (msglevel, "RESOLVE: Sorry, but we only accept IPv4 DNS names: %s", hostname);
- goto done;
- }
-
- ia.s_addr = *(in_addr_t *) (h->h_addr_list[0]);
-
- if (ia.s_addr)
- {
- if (h->h_addr_list[1]) /* more than one address returned */
- {
- int n = 0;
-
- /* count address list */
- while (h->h_addr_list[n])
- ++n;
- ASSERT (n >= 2);
-
- msg (D_RESOLVE_ERRORS, "RESOLVE: NOTE: %s resolves to %d addresses",
- hostname,
- n);
-
- /* choose address randomly, for basic load-balancing capability */
- /*ia.s_addr = *(in_addr_t *) (h->h_addr_list[get_random () % n]);*/
-
- /* choose first address */
- ia.s_addr = *(in_addr_t *) (h->h_addr_list[0]);
-
- if (reslist)
- {
- int i;
- for (i = 0; i < n && i < SIZE(reslist->data); ++i)
- {
- in_addr_t a = *(in_addr_t *) (h->h_addr_list[i]);
- if (flags & GETADDR_HOST_ORDER)
- a = ntohl(a);
- reslist->data[i] = a;
- }
- reslist->len = i;
- }
- }
- }
-
- /* hostname resolve succeeded */
- if (succeeded)
- *succeeded = true;
- }
- else
- {
- /* IP address parse succeeded */
- if (succeeded)
- *succeeded = true;
- }
-
- done:
- if (signal_received && *signal_received)
- {
- int level = 0;
- if (flags & GETADDR_FATAL_ON_SIGNAL)
- level = M_FATAL;
- else if (flags & GETADDR_WARN_ON_SIGNAL)
- level = M_WARN;
- msg (level, "RESOLVE: signal received during DNS resolution attempt");
- }
-
- gc_free (&gc);
- return (flags & GETADDR_HOST_ORDER) ? ntohl (ia.s_addr) : ia.s_addr;
+ status = openvpn_getaddrinfo(flags, hostname, resolve_retry_seconds,
+ signal_received, AF_INET, &ai);
+ if(status==0) {
+ struct in_addr ia;
+ if(succeeded)
+ *succeeded=true;
+ ia = ((struct sockaddr_in*)ai->ai_addr)->sin_addr;
+ freeaddrinfo(ai);
+ return (flags & GETADDR_HOST_ORDER) ? ntohl (ia.s_addr) : ia.s_addr;
+ } else {
+ if(succeeded)
+ *succeeded =false;
+ return 0;
+ }
}
+
/*
- * Translate IPv6 addr or hostname into struct addrinfo
- * If resolve error, try again for
- * resolve_retry_seconds seconds.
+ * Translate IPv4/IPv6 addr or hostname into struct addrinfo
+ * If resolve error, try again for resolve_retry_seconds seconds.
*/
-bool
-getaddr6 (unsigned int flags,
- const char *hostname,
- int resolve_retry_seconds,
- volatile int *signal_received,
- int *gai_err,
- struct sockaddr_in6 *in6)
-{
- bool success;
- struct addrinfo hints, *ai;
+int
+openvpn_getaddrinfo (unsigned int flags,
+ const char *hostname,
+ int resolve_retry_seconds,
+ volatile int *signal_received,
+ int ai_family,
+ struct addrinfo **res)
+{
+ struct addrinfo hints;
int status;
int sigrec = 0;
int msglevel = (flags & GETADDR_FATAL) ? M_FATAL : D_RESOLVE_ERRORS;
struct gc_arena gc = gc_new ();
- ASSERT(in6);
+ ASSERT(res);
+
+#if defined(HAVE_RES_INIT)
+ res_init ();
+#endif
if (!hostname)
hostname = "::";
@@ -317,151 +150,111 @@ getaddr6 (unsigned int flags,
if (flags & GETADDR_MSG_VIRT_OUT)
msglevel |= M_MSG_VIRT_OUT;
- CLEAR (ai);
- success = false;
-
if ((flags & (GETADDR_FATAL_ON_SIGNAL|GETADDR_WARN_ON_SIGNAL))
&& !signal_received)
signal_received = &sigrec;
/* try numeric ipv6 addr first */
CLEAR(hints);
- hints.ai_family = AF_INET6;
+ hints.ai_family = ai_family;
hints.ai_flags = AI_NUMERICHOST;
- if ((status = getaddrinfo(hostname, NULL, &hints, &ai))==0)
- {
- *in6 = *((struct sockaddr_in6 *)(ai->ai_addr));
- freeaddrinfo(ai);
- ai = NULL;
- }
- if (gai_err)
- *gai_err = status;
+ hints.ai_socktype = dnsflags_to_socktype(flags);
+ status = getaddrinfo(hostname, NULL, &hints, res);
- if (status != 0) /* parse as IPv6 address failed? */
+ if (status != 0) /* parse as numeric address failed? */
{
const int fail_wait_interval = 5; /* seconds */
int resolve_retries = (flags & GETADDR_TRY_ONCE) ? 1 : (resolve_retry_seconds / fail_wait_interval);
const char *fmt;
int level = 0;
- int err;
-
- ai = NULL;
fmt = "RESOLVE: Cannot resolve host address: %s: %s";
if ((flags & GETADDR_MENTION_RESOLVE_RETRY)
- && !resolve_retry_seconds)
- fmt = "RESOLVE: Cannot resolve host address: %s: %s (I would have retried this name query if you had specified the --resolv-retry option.)";
+ && !resolve_retry_seconds)
+ fmt = "RESOLVE: Cannot resolve host address: %s: %s (I would have retried this name query if you had specified the --resolv-retry option.)";
if (!(flags & GETADDR_RESOLVE) || status == EAI_FAIL)
- {
- msg (msglevel, "RESOLVE: Cannot parse IPv6 address: %s", hostname);
- goto done;
- }
+ {
+ msg (msglevel, "RESOLVE: Cannot parse IP address: %s", hostname);
+ goto done;
+ }
#ifdef ENABLE_MANAGEMENT
if (flags & GETADDR_UPDATE_MANAGEMENT_STATE)
- {
- if (management)
- management_set_state (management,
- OPENVPN_STATE_RESOLVE,
- NULL,
- (in_addr_t)0,
- (in_addr_t)0);
- }
+ {
+ if (management)
+ management_set_state (management,
+ OPENVPN_STATE_RESOLVE,
+ NULL,
+ (in_addr_t)0,
+ (in_addr_t)0);
+ }
#endif
/*
* Resolve hostname
*/
while (true)
- {
- /* try hostname lookup */
+ {
+ /* try hostname lookup */
hints.ai_flags = 0;
- hints.ai_socktype = dnsflags_to_socktype(flags);
- dmsg (D_SOCKET_DEBUG, "GETADDR6 flags=0x%04x ai_family=%d ai_socktype=%d",
- flags, hints.ai_family, hints.ai_socktype);
- err = getaddrinfo(hostname, NULL, &hints, &ai);
-
- if (gai_err)
- *gai_err = err;
+ dmsg (D_SOCKET_DEBUG, "GETADDRINFO flags=0x%04x ai_family=%d ai_socktype=%d",
+ flags, hints.ai_family, hints.ai_socktype);
+ status = getaddrinfo(hostname, NULL, &hints, res);
- if (signal_received)
- {
- get_signal (signal_received);
- if (*signal_received) /* were we interrupted by a signal? */
- {
- if (0 == err) {
- ASSERT(ai);
- freeaddrinfo(ai);
- ai = NULL;
+ if (signal_received)
+ {
+ get_signal (signal_received);
+ if (*signal_received) /* were we interrupted by a signal? */
+ {
+ if (0 == status) {
+ ASSERT(res);
+ freeaddrinfo(*res);
+ res = NULL;
}
- if (*signal_received == SIGUSR1) /* ignore SIGUSR1 */
- {
- msg (level, "RESOLVE: Ignored SIGUSR1 signal received during DNS resolution attempt");
- *signal_received = 0;
- }
- else
- goto done;
- }
- }
-
- /* success? */
- if (0 == err)
- break;
-
- /* resolve lookup failed, should we
- continue or fail? */
-
- level = msglevel;
- if (resolve_retries > 0)
- level = D_RESOLVE_ERRORS;
-
- msg (level,
- fmt,
- hostname,
- gai_strerror(err));
-
- if (--resolve_retries <= 0)
- goto done;
-
- openvpn_sleep (fail_wait_interval);
- }
+ if (*signal_received == SIGUSR1) /* ignore SIGUSR1 */
+ {
+ msg (level, "RESOLVE: Ignored SIGUSR1 signal received during DNS resolution attempt");
+ *signal_received = 0;
+ }
+ else
+ goto done;
+ }
+ }
- ASSERT(ai);
+ /* success? */
+ if (0 == status)
+ break;
- if (!ai->ai_next)
- *in6 = *((struct sockaddr_in6*)(ai->ai_addr));
- else
- /* more than one address returned */
- {
- struct addrinfo *ai_cursor;
- int n = 0;
- /* count address list */
- for (ai_cursor = ai; ai_cursor; ai_cursor = ai_cursor->ai_next) n++;
- ASSERT (n >= 2);
+ /* resolve lookup failed, should we
+ continue or fail? */
+ level = msglevel;
+ if (resolve_retries > 0)
+ level = D_RESOLVE_ERRORS;
- msg (D_RESOLVE_ERRORS, "RESOLVE: NOTE: %s resolves to %d ipv6 addresses, choosing one by random",
+ msg (level,
+ fmt,
hostname,
- n);
+ gai_strerror(status));
+
+ if (--resolve_retries <= 0)
+ goto done;
- /* choose address randomly, for basic load-balancing capability */
- n--;
- n %= get_random();
- for (ai_cursor = ai; n; ai_cursor = ai_cursor->ai_next) n--;
- *in6 = *((struct sockaddr_in6*)(ai_cursor->ai_addr));
+ openvpn_sleep (fail_wait_interval);
}
- freeaddrinfo(ai);
- ai = NULL;
+ ASSERT(res);
/* hostname resolve succeeded */
- success = true;
+
+ /* Do not chose an IP Addresse by random or change the order *
+ * of IP addresses, doing so will break RFC 3484 address selection *
+ */
}
else
{
/* IP address parse succeeded */
- success = true;
}
done:
@@ -469,14 +262,14 @@ getaddr6 (unsigned int flags,
{
int level = 0;
if (flags & GETADDR_FATAL_ON_SIGNAL)
- level = M_FATAL;
+ level = M_FATAL;
else if (flags & GETADDR_WARN_ON_SIGNAL)
- level = M_WARN;
+ level = M_WARN;
msg (level, "RESOLVE: signal received during DNS resolution attempt");
}
gc_free (&gc);
- return success;
+ return status;
}
/*
@@ -652,18 +445,16 @@ update_remote (const char* host,
case AF_INET6:
if (host && addr)
{
- struct sockaddr_in6 sin6;
- int success;
- CLEAR(sin6);
- success = getaddr6 (
- sf2gaf(GETADDR_RESOLVE|GETADDR_UPDATE_MANAGEMENT_STATE, sockflags),
- host,
- 1,
- NULL,
- NULL,
- &sin6);
- if ( success )
+ int status;
+ struct addrinfo* ai;
+
+ status = openvpn_getaddrinfo(sf2gaf(GETADDR_RESOLVE|GETADDR_UPDATE_MANAGEMENT_STATE, sockflags), host, 1, NULL, AF_INET6, &ai);
+
+ if ( status ==0 )
{
+ struct sockaddr_in6 sin6;
+ CLEAR(sin6);
+ sin6 = *((struct sockaddr_in6*)ai->ai_addr);
if (!IN6_ARE_ADDR_EQUAL(&sin6.sin6_addr, &addr->addr.in6.sin6_addr))
{
int port = addr->addr.in6.sin6_port;
@@ -671,6 +462,7 @@ update_remote (const char* host,
addr->addr.in6 = sin6;
addr->addr.in6.sin6_port = port;
}
+ freeaddrinfo(ai);
}
}
break;
@@ -1355,25 +1147,27 @@ resolve_bind_local (struct link_socket *sock)
break;
case AF_INET6:
{
- int success;
+ int status;
int err;
CLEAR(sock->info.lsa->local.addr.in6);
if (sock->local_host)
{
- success = getaddr6(GETADDR_RESOLVE | GETADDR_WARN_ON_SIGNAL | GETADDR_FATAL,
- sock->local_host,
- 0,
- NULL,
- &err,
- &sock->info.lsa->local.addr.in6);
+ struct addrinfo *ai;
+
+ status = openvpn_getaddrinfo(GETADDR_RESOLVE | GETADDR_WARN_ON_SIGNAL | GETADDR_FATAL,
+ sock->local_host, 0, NULL, AF_INET6, &ai);
+ if(status ==0) {
+ sock->info.lsa->local.addr.in6 = *((struct sockaddr_in6*)(ai->ai_addr));
+ freeaddrinfo(ai);
+ }
}
else
{
sock->info.lsa->local.addr.in6.sin6_family = AF_INET6;
sock->info.lsa->local.addr.in6.sin6_addr = in6addr_any;
- success = true;
+ status = 0;
}
- if (!success)
+ if (!status == 0)
{
msg (M_FATAL, "getaddr6() failed for local \"%s\": %s",
sock->local_host,
@@ -1430,7 +1224,7 @@ resolve_remote (struct link_socket *sock,
{
unsigned int flags = sf2gaf(GETADDR_RESOLVE|GETADDR_UPDATE_MANAGEMENT_STATE, sock->sockflags);
int retry = 0;
- bool status = false;
+ int status = -1;
if (sock->connection_profiles_defined && sock->resolve_retry_seconds == RESOLV_RETRY_INFINITE)
{
@@ -1467,40 +1261,27 @@ resolve_remote (struct link_socket *sock,
ASSERT (0);
}
- switch(af)
- {
- case AF_INET:
- sock->info.lsa->remote.addr.in4.sin_addr.s_addr = getaddr (
- flags,
- sock->remote_host,
- retry,
- &status,
- signal_received);
- break;
- case AF_INET6:
- status = getaddr6 (
- flags,
- sock->remote_host,
- retry,
- signal_received,
- NULL,
- &sock->info.lsa->remote.addr.in6);
- break;
- }
-
- dmsg (D_SOCKET_DEBUG, "RESOLVE_REMOTE flags=0x%04x phase=%d rrs=%d sig=%d status=%d",
- flags,
- phase,
- retry,
- signal_received ? *signal_received : -1,
- status);
-
+ struct addrinfo* ai;
+ /* Temporary fix, this need to be changed for dual stack */
+ status = openvpn_getaddrinfo(flags, sock->remote_host, retry,
+ signal_received, af, &ai);
+ if(status == 0) {
+ sock->info.lsa->remote.addr.in6 = *((struct sockaddr_in6*)(ai->ai_addr));
+ freeaddrinfo(ai);
+
+ dmsg (D_SOCKET_DEBUG, "RESOLVE_REMOTE flags=0x%04x phase=%d rrs=%d sig=%d status=%d",
+ flags,
+ phase,
+ retry,
+ signal_received ? *signal_received : -1,
+ status);
+ }
if (signal_received)
{
if (*signal_received)
goto done;
}
- if (!status)
+ if (status!=0)
{
if (signal_received)
*signal_received = SIGUSR1;
diff --git a/src/openvpn/socket.h b/src/openvpn/socket.h
index 43f72dc..44f1098 100644
--- a/src/openvpn/socket.h
+++ b/src/openvpn/socket.h
@@ -467,11 +467,6 @@ bool unix_socket_get_peer_uid_gid (const socket_descriptor_t sd, int *uid, int *
* DNS resolution
*/
-struct resolve_list {
- int len;
- in_addr_t data[16];
-};
-
#define GETADDR_RESOLVE (1<<0)
#define GETADDR_FATAL (1<<1)
#define GETADDR_HOST_ORDER (1<<2)
@@ -494,12 +489,12 @@ in_addr_t getaddr (unsigned int flags,
bool *succeeded,
volatile int *signal_received);
-in_addr_t getaddr_multi (unsigned int flags,
- const char *hostname,
- int resolve_retry_seconds,
- bool *succeeded,
- volatile int *signal_received,
- struct resolve_list *reslist);
+int openvpn_getaddrinfo (unsigned int flags,
+ const char *hostname,
+ int resolve_retry_seconds,
+ volatile int *signal_received,
+ int ai_family,
+ struct addrinfo **res);
/*
* Transport protocol naming and other details.