zeek/src/FileAnalyzer.cc
2011-11-01 14:44:38 -05:00

86 lines
1.7 KiB
C++

#include <algorithm>
#include "FileAnalyzer.h"
#include "Reporter.h"
#ifdef HAVE_LIBMAGIC
magic_t File_Analyzer::magic = 0;
magic_t File_Analyzer::magic_mime = 0;
#endif
File_Analyzer::File_Analyzer(Connection* conn)
: TCP_ApplicationAnalyzer(AnalyzerTag::File, conn)
{
buffer_len = 0;
#ifdef HAVE_LIBMAGIC
if ( ! magic )
{
InitMagic(&magic, MAGIC_NONE);
InitMagic(&magic_mime, MAGIC_MIME);
}
#endif
}
void File_Analyzer::DeliverStream(int len, const u_char* data, bool orig)
{
TCP_ApplicationAnalyzer::DeliverStream(len, data, orig);
int n = min(len, BUFFER_SIZE - buffer_len);
if ( n )
{
strncpy(buffer + buffer_len, (const char*) data, n);
buffer_len += n;
if ( buffer_len == BUFFER_SIZE )
Identify();
}
return;
}
void File_Analyzer::Done()
{
TCP_ApplicationAnalyzer::Done();
if ( buffer_len && buffer_len != BUFFER_SIZE )
Identify();
}
void File_Analyzer::Identify()
{
const char* descr = 0;
const char* mime = 0;
#ifdef HAVE_LIBMAGIC
if ( magic )
descr = magic_buffer(magic, buffer, buffer_len);
if ( magic_mime )
mime = magic_buffer(magic_mime, buffer, buffer_len);
#endif
val_list* vl = new val_list;
vl->append(BuildConnVal());
vl->append(new StringVal(buffer_len, buffer));
vl->append(new StringVal(descr ? descr : "<unknown>"));
vl->append(new StringVal(mime ? mime : "<unknown>"));
ConnectionEvent(file_transferred, vl);
}
#ifdef HAVE_LIBMAGIC
void File_Analyzer::InitMagic(magic_t* magic, int flags)
{
*magic = magic_open(flags);
if ( ! *magic )
reporter->Error("%s", fmt("can't init libmagic: %s", magic_error(*magic)));
else if ( magic_load(*magic, 0) < 0 )
{
reporter->Error("%s", fmt("can't load magic file: %s", magic_error(*magic)));
magic_close(*magic);
*magic = 0;
}
}
#endif