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putty/mac/mtcpnet.c

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/*
* Copyright (c) 2003 Ben Harris
* All rights reserved.
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following
* conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
/*
* mtcpnet.c - MacTCP interface
*/
#include <MacTypes.h>
#include <Devices.h>
#include <Endian.h>
#include <Folders.h>
#include <MacTCP.h>
#include <MixedMode.h>
#include <Resources.h>
#include <assert.h>
#define DEFINE_PLUG_METHOD_MACROS
#include "putty.h"
#include "network.h"
#include "mac.h"
/*
* The following structures are documented as being in
* <AddressXlation.h>, but that isn't shipped with Universal
* Interfaces, and it's easier to define them here than to require
* people to download yet another SDK.
*/
static OSErr OpenResolver(char *);
static OSErr CloseResolver(void);
enum {
OPENRESOLVER = 1,
CLOSERESOLVER,
STRTOADDR,
ADDRTOSTR,
ENUMCACHE,
ADDRTONAME,
HXINFO,
MXINFO
};
#define NUM_ALT_ADDRS 4
typedef struct hostInfo {
int rtnCode;
char cname[255];
unsigned long addr[NUM_ALT_ADDRS];
};
typedef CALLBACK_API(void, ResultProcPtr)(struct hostInfo *, char *);
typedef STACK_UPP_TYPE(ResultProcPtr) ResultUPP;
enum { uppResultProcInfo = kPascalStackBased
| STACK_ROUTINE_PARAMETER(1, SIZE_CODE(sizeof(struct hostInfo*)))
| STACK_ROUTINE_PARAMETER(2, SIZE_CODE(sizeof(char *)))
};
#define NewResultUPP(userRoutine) \
(ResultUPP)NewRoutineDescriptor((ProcPtr)(userRoutine), \
uppResultProcInfo, \
GetCurrentArchitecture())
#define DisposeResultUPP(userUPP) DisposeRoutineDescriptor(userUPP)
static OSErr StrToAddr(char *, struct hostInfo *, ResultUPP *, char *);
typedef CALLBACK_API_C(OSErr, OpenResolverProcPtr)(UInt32, char *);
typedef STACK_UPP_TYPE(OpenResolverProcPtr) OpenResolverUPP;
enum { uppOpenResolverProcInfo = kCStackBased
| RESULT_SIZE(SIZE_CODE(sizeof(OSErr)))
| STACK_ROUTINE_PARAMETER(1, SIZE_CODE(sizeof(UInt32)))
| STACK_ROUTINE_PARAMETER(2, SIZE_CODE(sizeof(char*)))
};
#define InvokeOpenResolverUPP(selector, fileName, userUPP) \
CALL_TWO_PARAMETER_UPP((userUPP), uppOpenResolverProcInfo, \
(selector), (fileName))
typedef CALLBACK_API_C(OSErr, CloseResolverProcPtr)(UInt32);
typedef STACK_UPP_TYPE(CloseResolverProcPtr) CloseResolverUPP;
enum { uppCloseResolverProcInfo = kCStackBased
| RESULT_SIZE(SIZE_CODE(sizeof(OSErr)))
| STACK_ROUTINE_PARAMETER(1, SIZE_CODE(sizeof(UInt32)))
};
#define InvokeCloseResolverUPP(selector, userUPP) \
CALL_ONE_PARAMETER_UPP((userUPP), uppCloseResolverProcInfo, (selector))
typedef CALLBACK_API_C(OSErr, StrToAddrProcPtr)(UInt32, char *,
struct hostInfo *, ResultUPP,
char *);
typedef STACK_UPP_TYPE(StrToAddrProcPtr) StrToAddrUPP;
enum { uppStrToAddrProcInfo = kCStackBased
| RESULT_SIZE(SIZE_CODE(sizeof(OSErr)))
| STACK_ROUTINE_PARAMETER(1, SIZE_CODE(sizeof(UInt32)))
| STACK_ROUTINE_PARAMETER(2, SIZE_CODE(sizeof(char *)))
| STACK_ROUTINE_PARAMETER(3, SIZE_CODE(sizeof(struct hostInfo *)))
| STACK_ROUTINE_PARAMETER(4, SIZE_CODE(sizeof(ResultUPP)))
| STACK_ROUTINE_PARAMETER(5, SIZE_CODE(sizeof(char *)))
};
#define InvokeStrToAddrUPP(selector, hostName, hostInfoPtr, ResultProc, \
userDataPtr, userUPP) \
CALL_FIVE_PARAMETER_UPP((userUPP), uppStrToAddrProcInfo, (selector),\
(hostName), (hostInfoPtr), (ResultProc), \
(userDataPtr))
#define StrToAddr(hostName, hostInfoPtr, ResultProc, userDataPtr) \
InvokeStrToAddrUPP(STRTOADDR, hostName, hostInfoPtr, ResultProc, \
userDataPtr, (StrToAddrUPP)*mactcp.dnr_handle)
typedef CALLBACK_API_C(OSErr, AddrToStrProcPtr)(UInt32, unsigned long, char *);
typedef STACK_UPP_TYPE(AddrToStrProcPtr) AddrToStrUPP;
enum { uppAddrToStrProcInfo = kCStackBased
| RESULT_SIZE(SIZE_CODE(sizeof(OSErr)))
| STACK_ROUTINE_PARAMETER(1, SIZE_CODE(sizeof(unsigned long)))
| STACK_ROUTINE_PARAMETER(2, SIZE_CODE(sizeof(char *)))
};
#define InvokeAddrToStrUPP(selector, addr, addrStr, userUPP) \
CALL_THREE_PARAMETER_UPP((userUPP), uppAddrToStrProcInfo, (selector),\
(addr), (addrStr))
#define AddrToStr(addr, addrStr) \
InvokeAddrToStrUPP(ADDRTOSTR, addr, addrStr, \
(AddrToStrUPP)*mactcp.dnr_handle)
/* End of AddressXlation.h bits */
struct Socket_tag {
struct socket_function_table *fn;
/* the above variable absolutely *must* be the first in this structure */
StreamPtr s;
OSErr err;
Plug plug;
void *private_ptr;
bufchain output_data;
int connected;
int writable;
int frozen; /* this causes readability notifications to be ignored */
int frozen_readable; /* this means we missed at least one readability
* notification while we were frozen */
int localhost_only; /* for listening sockets */
char oobdata[1];
int sending_oob;
int oobpending; /* is there OOB data available to read? */
int oobinline;
int pending_error; /* in case send() returns error */
int listener;
struct Socket_tag *next;
struct Socket_tag **prev;
};
/*
* We used to typedef struct Socket_tag *Socket.
*
* Since we have made the networking abstraction slightly more
* abstract, Socket no longer means a tcp socket (it could mean
* an ssl socket). So now we must use Actual_Socket when we know
* we are talking about a tcp socket.
*/
typedef struct Socket_tag *Actual_Socket;
struct SockAddr_tag {
int resolved;
struct hostInfo hostinfo;
char hostname[512];
};
/* Global variables */
static struct {
Handle dnr_handle;
int initialised;
short refnum;
Actual_Socket socklist;
} mactcp;
static pascal void mactcp_lookupdone(struct hostInfo *hi, char *cookie);
static Plug mactcp_plug(Socket, Plug);
static void mactcp_flush(Socket);
static void mactcp_close(Socket);
static int mactcp_write(Socket, char *, int);
static int mactcp_write_oob(Socket, char *, int);
static void mactcp_set_private_ptr(Socket, void *);
static void *mactcp_get_private_ptr(Socket);
static char *mactcp_socket_error(Socket);
static void mactcp_set_frozen(Socket, int);
static void mactcp_recv(Actual_Socket s, size_t len);
/*
* Initialise MacTCP.
* This should be called once before any TCP connection is opened.
*/
OSErr mactcp_init(void)
{
OSErr err;
/*
* IM:Devices describes a convoluted way of finding a spare unit
* number to open a driver on before calling OpenDriver. Happily,
* the MacTCP INIT ensures that .IPP is already open (and hence
* has a valid unit number already) so we don't need to go through
* all that. (MacTCP Programmer's Guide p6)
*/
err = OpenDriver("\p.IPP", &mactcp.refnum);
if (err != noErr) return err;
err = OpenResolver(NULL);
if (err != noErr) return err;
mactcp.initialised = TRUE;
return noErr;
}
void mactcp_shutdown(void)
{
CloseResolver();
mactcp.initialised = FALSE;
}
static ResultUPP mactcp_lookupdone_upp;
SockAddr sk_namelookup(char *host, char **canonicalname)
{
SockAddr ret = smalloc(sizeof(struct SockAddr_tag));
OSErr err;
volatile int done = FALSE;
char *realhost;
fprintf(stderr, "Resolving %s...\n", host);
/* Clear the structure. */
memset(ret, 0, sizeof(struct SockAddr_tag));
if (mactcp_lookupdone_upp == NULL)
mactcp_lookupdone_upp = NewResultUPP(&mactcp_lookupdone);
err = StrToAddr(host, &ret->hostinfo, mactcp_lookupdone_upp,
(char *)&done);
/*
* PuTTY expects DNS lookups to be synchronous (see bug
* "async-dns"), so we pretend they are.
*/
if (err == cacheFault)
while (!done)
continue;
ret->resolved = TRUE;
if (ret->hostinfo.rtnCode == noErr)
realhost = ret->hostinfo.cname;
else
realhost = "";
*canonicalname = smalloc(1+strlen(realhost));
strcpy(*canonicalname, realhost);
fprintf(stderr, "canonical name = %s\n", realhost);
return ret;
}
static pascal void mactcp_lookupdone(struct hostInfo *hi, char *cookie)
{
volatile int *donep = (int *)cookie;
*donep = TRUE;
}
SockAddr sk_nonamelookup(char *host)
{
SockAddr ret = smalloc(sizeof(struct SockAddr_tag));
ret->resolved = FALSE;
ret->hostinfo.rtnCode = noErr;
ret->hostname[0] = '\0';
strncat(ret->hostname, host, lenof(ret->hostname) - 1);
return ret;
}
void sk_getaddr(SockAddr addr, char *buf, int buflen)
{
char mybuf[16];
OSErr err;
if (addr->resolved) {
/* XXX only return first address */
err = AddrToStr(addr->hostinfo.addr[0], mybuf);
buf[0] = '\0';
if (err != noErr)
strncat(buf, mybuf, buflen - 1);
} else {
buf[0] = '\0';
strncat(buf, addr->hostname, buflen - 1);
}
}
/* I think "local" here really means "loopback" */
int sk_hostname_is_local(char *name)
{
return !strcmp(name, "localhost");
}
int sk_address_is_local(SockAddr addr)
{
int i;
if (addr->resolved)
for (i = 0; i < NUM_ALT_ADDRS; i++)
if (addr->hostinfo.addr[i] & 0xff000000 == 0x7f000000)
return TRUE;
return FALSE;
}
int sk_addrtype(SockAddr addr)
{
if (addr->resolved)
return ADDRTYPE_IPV4;
return ADDRTYPE_NAME;
}
void sk_addrcopy(SockAddr addr, char *buf)
{
/* XXX only return first address */
memcpy(buf, &addr->hostinfo.addr[0], 4);
}
void sk_addr_free(SockAddr addr)
{
sfree(addr);
}
static Plug mactcp_plug(Socket sock, Plug p)
{
Actual_Socket s = (Actual_Socket) sock;
Plug ret = s->plug;
if (p)
s->plug = p;
return ret;
}
static void mactcp_flush(Socket s)
{
fatalbox("sk_tcp_flush");
}
Socket sk_new(SockAddr addr, int port, int privport, int oobinline,
int nodelay, Plug plug)
{
static struct socket_function_table fn_table = {
mactcp_plug,
mactcp_close,
mactcp_write,
mactcp_write_oob,
mactcp_flush,
mactcp_set_private_ptr,
mactcp_get_private_ptr,
mactcp_set_frozen,
mactcp_socket_error
};
TCPiopb pb;
UDPiopb upb;
Actual_Socket ret;
ip_addr dstaddr;
size_t buflen;
fprintf(stderr, "Opening socket, port = %d\n", port);
/*
* Create Socket structure.
*/
ret = smalloc(sizeof(struct Socket_tag));
ret->s = 0;
ret->fn = &fn_table;
ret->err = noErr;
ret->plug = plug;
bufchain_init(&ret->output_data);
ret->connected = 0; /* to start with */
ret->writable = 0; /* to start with */
ret->sending_oob = 0;
ret->frozen = 0;
ret->frozen_readable = 0;
ret->localhost_only = 0; /* unused, but best init anyway */
ret->pending_error = 0;
ret->oobinline = oobinline;
ret->oobpending = FALSE;
ret->listener = 0;
dstaddr = addr->hostinfo.addr[0]; /* XXX should try all of them */
/*
* Create a TCP stream.
*
* MacTCP requires us to provide it with some buffer memory. Page
* 31 of the Programmer's Guide says it should be a minimum of
* 4*MTU+1024. Page 36 says a minimum of 4096 bytes. Assume
* they're both correct.
*/
assert(addr->resolved);
upb.ioCRefNum = mactcp.refnum;
upb.csCode = UDPMaxMTUSize;
upb.csParam.mtu.remoteHost = dstaddr;
upb.csParam.mtu.userDataPtr = NULL;
ret->err = PBControlSync((ParmBlkPtr)&upb);
fprintf(stderr, "getting mtu, err = %d\n", ret->err);
if (ret->err != noErr) return (Socket)ret;
fprintf(stderr, "Got MTU = %d\n", upb.csParam.mtu.mtuSize);
buflen = upb.csParam.mtu.mtuSize * 4 + 1024;
if (buflen < 4096) buflen = 4096;
pb.ioCRefNum = mactcp.refnum;
pb.csCode = TCPCreate;
pb.csParam.create.rcvBuff = smalloc(buflen);
pb.csParam.create.rcvBuffLen = buflen;
pb.csParam.create.notifyProc = NULL;
pb.csParam.create.userDataPtr = (Ptr)ret;
ret->err = PBControlSync((ParmBlkPtr)&pb);
if (ret->err != noErr) return (Socket)ret;
ret->s = pb.tcpStream;
fprintf(stderr, "stream opened\n");
/*
* Open the connection.
*/
pb.ioCRefNum = mactcp.refnum;
pb.csCode = TCPActiveOpen;
pb.tcpStream = ret->s;
pb.csParam.open.validityFlags = 0;
pb.csParam.open.remoteHost = dstaddr;
pb.csParam.open.remotePort = port;
pb.csParam.open.localPort = privport ? 1023 : 0;
pb.csParam.open.dontFrag = FALSE;
pb.csParam.open.timeToLive = 0;
pb.csParam.open.security = 0;
pb.csParam.open.optionCnt = 0;
pb.csParam.open.userDataPtr = (Ptr)ret;
while (1) {
ret->err = PBControlSync((ParmBlkPtr)&pb);
if (!privport || ret->err != duplicateSocket)
break;
pb.csParam.open.localPort--;
if (pb.csParam.open.localPort == 0)
break;
}
if (ret->err != noErr) return (Socket)ret;
ret->connected = TRUE;
ret->writable = TRUE;
/* Add this to the list of all sockets */
ret->next = mactcp.socklist;
ret->prev = &mactcp.socklist;
mactcp.socklist = ret;
fprintf(stderr, "Socket connected\n");
return (Socket)ret;
}
static void mactcp_close(Socket sock)
{
Actual_Socket s = (Actual_Socket)sock;
TCPiopb pb;
/*
* TCPClose is equivalent to shutdown(fd, SHUT_WR), and hence
* leaves the Rx side open, while TCPAbort seems rather vicious,
* throwing away Tx data that haven't been ACKed yet. We do both
* in succession.
*/
pb.ioCRefNum = mactcp.refnum;
pb.csCode = TCPClose;
pb.tcpStream = s->s;
pb.csParam.close.validityFlags = 0;
pb.csParam.close.userDataPtr = (Ptr)s;
s->err = PBControlSync((ParmBlkPtr)&pb);
/* Not much we can do about an error anyway. */
pb.ioCRefNum = mactcp.refnum;
pb.csCode = TCPAbort;
pb.tcpStream = s->s;
pb.csParam.abort.userDataPtr = (Ptr)s;
s->err = PBControlSync((ParmBlkPtr)&pb);
/* Even less we can do about an error here. */
pb.ioCRefNum = mactcp.refnum;
pb.csCode = TCPRelease;
pb.tcpStream = s->s;
pb.csParam.create.userDataPtr = (Ptr)s;
s->err = PBControlSync((ParmBlkPtr)&pb);
if (s->err == noErr)
sfree(pb.csParam.create.rcvBuff);
/* Unhitch from list of sockets */
*s->prev = s->next;
if (s->next != NULL)
s->next->prev = s->prev;
sfree(s);
}
static int mactcp_write(Socket sock, char *buf, int len)
{
Actual_Socket s = (Actual_Socket) sock;
wdsEntry wds[2];
TCPiopb pb;
wds[0].length = len;
wds[0].ptr = buf;
wds[1].length = 0;
pb.ioCRefNum = mactcp.refnum;
pb.csCode = TCPSend;
pb.tcpStream = s->s;
pb.csParam.send.validityFlags = 0;
pb.csParam.send.pushFlag = TRUE; /* XXX we want it to return. */
pb.csParam.send.urgentFlag = 0;
pb.csParam.send.wdsPtr = (Ptr)wds;
pb.csParam.send.userDataPtr = (Ptr)s;
s->err = PBControlSync((ParmBlkPtr)&pb);
return 0;
}
static int mactcp_write_oob(Socket sock, char *buf, int len)
{
fatalbox("mactcp_write_oob");
}
/*
* Called from our event loop if there's work to do.
*/
void mactcp_poll(void)
{
Actual_Socket s;
TCPiopb pb;
for (s = mactcp.socklist; s != NULL; s = s->next) {
/* XXX above can't handle sockets being deleted. */
pb.ioCRefNum = mactcp.refnum;
pb.csCode = TCPStatus;
pb.tcpStream = s->s;
pb.csParam.status.userDataPtr = (Ptr)s;
s->err = PBControlSync((ParmBlkPtr)&pb);
if (s->err != noErr)
continue;
if (pb.csParam.status.amtUnreadData > 0)
mactcp_recv(s, pb.csParam.status.amtUnreadData);
/* Should check connectionState in case remote has closed */
}
}
static void mactcp_recv(Actual_Socket s, size_t len)
{
rdsEntry rds[2];
TCPiopb pb;
if (s->frozen) return;
while (len > 0) {
pb.ioCRefNum = mactcp.refnum;
pb.csCode = TCPNoCopyRcv;
pb.tcpStream = s->s;
pb.csParam.receive.commandTimeoutValue = 0;
pb.csParam.receive.rdsPtr = (Ptr)rds;
pb.csParam.receive.rdsLength = lenof(rds) - 1;
pb.csParam.receive.userDataPtr = (Ptr)s;
s->err = PBControlSync((ParmBlkPtr)&pb);
if (s->err != noErr)
return;
plug_receive(s->plug, 0, rds[0].ptr, rds[0].length);
len -= rds[0].length;
pb.csCode = TCPRcvBfrReturn;
s->err = PBControlSync((ParmBlkPtr)&pb);
if (s->err != noErr)
return;
}
}
/*
* Each socket abstraction contains a `void *' private field in
* which the client can keep state.
*/
static void mactcp_set_private_ptr(Socket sock, void *ptr)
{
Actual_Socket s = (Actual_Socket) sock;
s->private_ptr = ptr;
}
static void *mactcp_get_private_ptr(Socket sock)
{
Actual_Socket s = (Actual_Socket) sock;
return s->private_ptr;
}
/*
* Special error values are returned from sk_namelookup and sk_new
* if there's a problem. These functions extract an error message,
* or return NULL if there's no problem.
*/
char *sk_addr_error(SockAddr addr)
{
static char buf[64];
switch (addr->hostinfo.rtnCode) {
case noErr:
return NULL;
case nameSyntaxErr:
return "Name syntax error";
case noNameServer:
return "No name server found";
case authNameErr:
return "Domain name does not exist";
case noAnsErr:
return "No answer from domain name server";
case dnrErr:
return "Domain name server returned an error";
case outOfMemory:
return "Out of memory";
default:
sprintf(buf, "Unknown DNR error %d", addr->hostinfo.rtnCode);
return buf;
}
}
static char *mactcp_socket_error(Socket sock)
{
static char buf[64];
Actual_Socket s = (Actual_Socket) sock;
switch (s->err) {
case noErr:
return NULL;
case insufficientResources:
return "Insufficient resources to open TCP stream";
case duplicateSocket:
return "Duplicate socket";
case openFailed:
return "Connection failed while opening";
default:
sprintf(buf, "Unknown MacTCP error %d", s->err);
return buf;
}
}
static void mactcp_set_frozen(Socket sock, int is_frozen)
{
Actual_Socket s = (Actual_Socket) sock;
if (s->frozen == is_frozen)
return;
s->frozen = is_frozen;
}
/*
* Bits below here would usually be in dnr.c, shipped with the MacTCP
* SDK, but its convenient not to require that, and since we assume
* System 7 we can actually simplify things a lot.
*/
static OSErr OpenResolver(char *hosts_file)
{
short vrefnum;
long dirid;
HParamBlockRec pb;
Str255 filename;
OSErr err;
int fd;
Handle dnr_handle;
if (mactcp.dnr_handle != NULL)
return noErr;
err = FindFolder(kOnSystemDisk, kControlPanelFolderType, FALSE, &vrefnum,
&dirid);
if (err != noErr) return err;
/*
* Might be better to use PBCatSearch here, but it's not always
* available.
*/
pb.fileParam.ioCompletion = NULL;
pb.fileParam.ioNamePtr = filename;
pb.fileParam.ioVRefNum = vrefnum;
pb.fileParam.ioFDirIndex = 1;
pb.fileParam.ioDirID = dirid;
fd = -1;
while (PBHGetFInfoSync(&pb) == noErr) {
if (pb.fileParam.ioFlFndrInfo.fdType == 'cdev' &&
pb.fileParam.ioFlFndrInfo.fdCreator == 'ztcp') {
fd = HOpenResFile(vrefnum, dirid, filename, fsRdPerm);
if (fd == -1) continue;
dnr_handle = Get1IndResource('dnrp', 1);
if (dnr_handle != NULL)
break;
CloseResFile(fd);
fd = -1;
}
pb.fileParam.ioDirID = dirid;
pb.fileParam.ioFDirIndex++;
}
if (fd == -1)
return fnfErr;
DetachResource(dnr_handle);
CloseResFile(fd);
MoveHHi(dnr_handle);
HLock(dnr_handle);
err = InvokeOpenResolverUPP(OPENRESOLVER, hosts_file,
(OpenResolverUPP)*dnr_handle);
if (err != noErr) {
HUnlock(dnr_handle);
DisposeHandle(dnr_handle);
return err;
}
mactcp.dnr_handle = dnr_handle;
return noErr;
}
OSErr CloseResolver(void)
{
Handle dnr_handle = mactcp.dnr_handle;
OSErr err;
if (mactcp.dnr_handle == NULL)
return notOpenErr;
err = InvokeCloseResolverUPP(CLOSERESOLVER,
(CloseResolverUPP)*mactcp.dnr_handle);
if (err != noErr)
return err;
mactcp.dnr_handle = NULL;
HUnlock(dnr_handle);
DisposeHandle(dnr_handle);
return noErr;
}
/*
* Local Variables:
* c-file-style: "simon"
* End:
*/
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