use strict;
use XML::Simple;

my $xml = <<EOX;
<FinInstnCdtTrf>
<GrpHdr>
<MsgId>0000003714</MsgId>
<CreDtTm>2013-03-04T16:01:57</CreDtTm>
<NbOfTxs>1</NbOfTxs>
<TtlIntrBkSttlmAmt Ccy="INR">234.00</TtlIntrBkSttlmAmt>
<IntrBkSttlmDt>2013-02-05</IntrBkSttlmDt>
<SttlmInf>
<SttlmMtd>CLRG</SttlmMtd>
</SttlmInf>
<InstgAgt>
<FinInstnId>
<ClrSysMmbId>
<MmbId>HOMEMEMEBER</MmbId>
</ClrSysMmbId>
</FinInstnId>
</InstgAgt>
<InstdAgt>
<FinInstnId>
<ClrSysMmbId>
<MmbId>FOREIGNMEMBER</MmbId>
</ClrSysMmbId>
</FinInstnId>
</InstdAgt>
</GrpHdr>
</FinInstnCdtTrf>
EOX

sub parsetree {
    my $ref = shift;
    my $txt = shift;
    foreach my $key ( keys %{$ref} ) {
	if( ref( $$ref{$key} ) =~ /HASH/ ) {
	    parsetree( $$ref{$key}, $txt."::".$key );
	} else {
	    print $txt."::".$key."::".$$ref{$key}."\n";
	}
    }
}
parsetree(XMLin($xml));