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Comparing Convert-BER-XS/XS.pm (file contents):
Revision 1.35 by root, Sat Apr 20 21:51:40 2019 UTC vs.
Revision 1.53 by root, Tue Apr 23 20:16:40 2019 UTC

… …
8 8
9 my $ber = ber_decode $buf, $Convert::BER::XS::SNMP_PROFILE 9 my $ber = ber_decode $buf, $Convert::BER::XS::SNMP_PROFILE
10 or die "unable to decode SNMP message"; 10 or die "unable to decode SNMP message";
11 11
12 # The above results in a data structure consisting of 12 # The above results in a data structure consisting of
13 # (class, tag, flags, data) 13 # (class, tag, flags, data)
14 # tuples. Below is such a message, SNMPv1 trap 14 # tuples. Below is such a message, SNMPv1 trap
15 # with a Cisco mac change notification. 15 # with a Cisco mac change notification.
16 # Did you know that Cisco is in the news almost 16 # Did you know that Cisco is in the news almost
17 # every week because of some backdoor password 17 # every week because of some backdoor password
18 # or other extremely stupid security bug? 18 # or other extremely stupid security bug?
… …
36 [ ASN_UNIVERSAL, ASN_OCTET_STRING, 0, "...data..." # the value 36 [ ASN_UNIVERSAL, ASN_OCTET_STRING, 0, "...data..." # the value
37 ] 37 ]
38 ] 38 ]
39 ], 39 ],
40 ... 40 ...
41 # let's dump it, for debugging
42
43 ber_dump $ber, $Convert::BER::XS::SNMP_PROFILE;
41 44
42 # let's decode it a bit with some helper functions 45 # let's decode it a bit with some helper functions
43 46
44 my $msg = ber_is_seq $ber 47 my $msg = ber_is_seq $ber
45 or die "SNMP message does not start with a sequence"; 48 or die "SNMP message does not start with a sequence";
… …
105 BER_CLASS BER_TAG BER_FLAGS BER_DATA 108 BER_CLASS BER_TAG BER_FLAGS BER_DATA
106 109
107=item C<:const_asn> 110=item C<:const_asn>
108 111
109ASN class values (these are C<0>, C<1>, C<2> and C<3>, respectively - 112ASN class values (these are C<0>, C<1>, C<2> and C<3>, respectively -
110exactly thw two topmost bits from the identifier octet shifted 6 bits to 113exactly the two topmost bits from the identifier octet shifted 6 bits to
111the right): 114the right):
112 115
113 ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE 116 ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE
114 117
115ASN tag values (some of which are aliases, such as C<ASN_OID>). Their 118ASN tag values (some of which are aliases, such as C<ASN_OID>). Their
116numerical value corresponds exactly to the numbers used in BER/X.690. 119numerical value corresponds exactly to the numbers used in BER/X.690.
117 120
118 ASN_BOOLEAN ASN_INTEGER ASN_BIT_STRING ASN_OCTET_STRING ASN_NULL ASN_OBJECT_IDENTIFIER 121 ASN_BOOLEAN ASN_INTEGER ASN_BIT_STRING ASN_OCTET_STRING ASN_NULL ASN_OID
119 ASN_OBJECT_DESCRIPTOR ASN_OID ASN_EXTERNAL ASN_REAL ASN_SEQUENCE ASN_ENUMERATED 122 ASN_OBJECT_IDENTIFIER ASN_OBJECT_DESCRIPTOR ASN_EXTERNAL ASN_REAL ASN_SEQUENCE ASN_ENUMERATED
120 ASN_EMBEDDED_PDV ASN_UTF8_STRING ASN_RELATIVE_OID ASN_SET ASN_NUMERIC_STRING 123 ASN_EMBEDDED_PDV ASN_UTF8_STRING ASN_RELATIVE_OID ASN_SET ASN_NUMERIC_STRING
121 ASN_PRINTABLE_STRING ASN_TELETEX_STRING ASN_T61_STRING ASN_VIDEOTEX_STRING ASN_IA5_STRING 124 ASN_PRINTABLE_STRING ASN_TELETEX_STRING ASN_T61_STRING ASN_VIDEOTEX_STRING ASN_IA5_STRING
122 ASN_ASCII_STRING ASN_UTC_TIME ASN_GENERALIZED_TIME ASN_GRAPHIC_STRING ASN_VISIBLE_STRING 125 ASN_ASCII_STRING ASN_UTC_TIME ASN_GENERALIZED_TIME ASN_GRAPHIC_STRING ASN_VISIBLE_STRING
123 ASN_ISO646_STRING ASN_GENERAL_STRING ASN_UNIVERSAL_STRING ASN_CHARACTER_STRING ASN_BMP_STRING 126 ASN_ISO646_STRING ASN_GENERAL_STRING ASN_UNIVERSAL_STRING ASN_CHARACTER_STRING ASN_BMP_STRING
124 127
… …
143 146
144C<ber_decode> and the match helper functions: 147C<ber_decode> and the match helper functions:
145 148
146 ber_decode ber-decode_prefix 149 ber_decode ber-decode_prefix
147 ber_is ber_is_seq ber_is_int ber_is_oid 150 ber_is ber_is_seq ber_is_int ber_is_oid
151 ber_dump
148 152
149=item C<:encode> 153=item C<:encode>
150 154
151C<ber_encode> and the construction helper functions: 155C<ber_encode> and the construction helper functions:
152 156
… …
292Also, since BER is self-delimited, this can be used to decode multiple BER 296Also, since BER is self-delimited, this can be used to decode multiple BER
293values joined together. 297values joined together.
294 298
295=item $bindata = ber_encode $tuple[, $profile] 299=item $bindata = ber_encode $tuple[, $profile]
296 300
297Encodes the BER tuple into a BER/DER data structure. AS with 301Encodes the BER tuple into a BER/DER data structure. As with
298Cyber_decode>, an optional profile can be given. 302Cyber_decode>, an optional profile can be given.
299 303
300The encoded data should be both BER and DER ("shortest form") compliant 304The encoded data should be both BER and DER ("shortest form") compliant
301unless the input says otherwise (e.g. it uses constructed strings). 305unless the input says otherwise (e.g. it uses constructed strings).
302 306
… …
408use Exporter qw(import); 412use Exporter qw(import);
409 413
410our $VERSION; 414our $VERSION;
411 415
412BEGIN { 416BEGIN {
413 $VERSION = '1.0'; 417 $VERSION = 1.11;
414 XSLoader::load __PACKAGE__, $VERSION; 418 XSLoader::load __PACKAGE__, $VERSION;
415} 419}
416 420
417our %EXPORT_TAGS = ( 421our %EXPORT_TAGS = (
418 const_index => [qw( 422 const_index => [qw(
419 BER_CLASS BER_TAG BER_FLAGS BER_DATA 423 BER_CLASS BER_TAG BER_FLAGS BER_DATA
420 )], 424 )],
425 const_asn_class => [qw(
426 ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE
427 )],
421 const_asn => [qw( 428 const_asn_tag => [qw(
422 ASN_BOOLEAN ASN_INTEGER ASN_BIT_STRING ASN_OCTET_STRING ASN_NULL ASN_OBJECT_IDENTIFIER 429 ASN_BOOLEAN ASN_INTEGER ASN_BIT_STRING ASN_OCTET_STRING ASN_NULL ASN_OID ASN_OBJECT_IDENTIFIER
423 ASN_OBJECT_DESCRIPTOR ASN_OID ASN_EXTERNAL ASN_REAL ASN_SEQUENCE ASN_ENUMERATED 430 ASN_OBJECT_DESCRIPTOR ASN_EXTERNAL ASN_REAL ASN_SEQUENCE ASN_ENUMERATED
424 ASN_EMBEDDED_PDV ASN_UTF8_STRING ASN_RELATIVE_OID ASN_SET ASN_NUMERIC_STRING 431 ASN_EMBEDDED_PDV ASN_UTF8_STRING ASN_RELATIVE_OID ASN_SET ASN_NUMERIC_STRING
425 ASN_PRINTABLE_STRING ASN_TELETEX_STRING ASN_T61_STRING ASN_VIDEOTEX_STRING ASN_IA5_STRING 432 ASN_PRINTABLE_STRING ASN_TELETEX_STRING ASN_T61_STRING ASN_VIDEOTEX_STRING ASN_IA5_STRING
426 ASN_ASCII_STRING ASN_UTC_TIME ASN_GENERALIZED_TIME ASN_GRAPHIC_STRING ASN_VISIBLE_STRING 433 ASN_ASCII_STRING ASN_UTC_TIME ASN_GENERALIZED_TIME ASN_GRAPHIC_STRING ASN_VISIBLE_STRING
427 ASN_ISO646_STRING ASN_GENERAL_STRING ASN_UNIVERSAL_STRING ASN_CHARACTER_STRING ASN_BMP_STRING 434 ASN_ISO646_STRING ASN_GENERAL_STRING ASN_UNIVERSAL_STRING ASN_CHARACTER_STRING ASN_BMP_STRING
428
429 ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE
430 )], 435 )],
431 const_ber_type => [qw( 436 const_ber_type => [qw(
432 BER_TYPE_BYTES BER_TYPE_UTF8 BER_TYPE_UCS2 BER_TYPE_UCS4 BER_TYPE_INT 437 BER_TYPE_BYTES BER_TYPE_UTF8 BER_TYPE_UCS2 BER_TYPE_UCS4 BER_TYPE_INT
433 BER_TYPE_OID BER_TYPE_RELOID BER_TYPE_NULL BER_TYPE_BOOL BER_TYPE_REAL 438 BER_TYPE_OID BER_TYPE_RELOID BER_TYPE_NULL BER_TYPE_BOOL BER_TYPE_REAL
434 BER_TYPE_IPADDRESS BER_TYPE_CROAK 439 BER_TYPE_IPADDRESS BER_TYPE_CROAK
… …
438 SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64 443 SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64
439 )], 444 )],
440 decode => [qw( 445 decode => [qw(
441 ber_decode ber_decode_prefix 446 ber_decode ber_decode_prefix
442 ber_is ber_is_seq ber_is_int ber_is_oid 447 ber_is ber_is_seq ber_is_int ber_is_oid
448 ber_dump
443 )], 449 )],
444 encode => [qw( 450 encode => [qw(
445 ber_encode 451 ber_encode
446 ber_int 452 ber_int
447 )], 453 )],
448); 454);
449 455
450our @EXPORT_OK = map @$_, values %EXPORT_TAGS; 456our @EXPORT_OK = map @$_, values %EXPORT_TAGS;
451 457
452$EXPORT_TAGS{all} = \@EXPORT_OK; 458$EXPORT_TAGS{all} = \@EXPORT_OK;
459$EXPORT_TAGS{const_asn} = [map @{ $EXPORT_TAGS{$_} }, qw(const_asn_class const_asn_tag)];
453$EXPORT_TAGS{const} = [map @{ $EXPORT_TAGS{$_} }, qw(const_index const_asn)]; 460$EXPORT_TAGS{const} = [map @{ $EXPORT_TAGS{$_} }, qw(const_index const_asn)];
461
462our $DEFAULT_PROFILE = new Convert::BER::XS::Profile;
463
464$DEFAULT_PROFILE->_set_default;
465
466# additional SNMP application types
467our $SNMP_PROFILE = new Convert::BER::XS::Profile;
468
469$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_IPADDRESS , BER_TYPE_IPADDRESS);
470$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER32 , BER_TYPE_INT);
471$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT);
472$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT);
473$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_IPADDRESS);
474
475=head2 DEBUGGING
476
477To aid debugging, you cna call the C<ber_dump> function to print a "nice"
478representation to STDOUT.
479
480=over
481
482=item ber_dump $tuple[, $profile[, $prefix]]
483
484In addition to specifying the BER C<$tuple> to dump, you can also specify
485a C<$profile> and a C<$prefix> string that is printed in front of each line.
486
487If C<$profile> is C<$Convert::BER::XS::SNMP_PROFILE>, then C<ber_dump>
488will try to improve its output for SNMP data.
489
490The output usually contains three columns, the "human readable" tag, the
491BER type used to decode it, and the data value.
492
493This function is somewhat slow and uses a number of heuristics and tricks,
494so it really is only suitable for debug prints.
495
496Example output:
497
498 SEQUENCE
499 | OCTET_STRING bytes 800063784300454045045400000001
500 | OCTET_STRING bytes
501 | CONTEXT (7) CONSTRUCTED
502 | | INTEGER int 1058588941
503 | | INTEGER int 0
504 | | INTEGER int 0
505 | | SEQUENCE
506 | | | SEQUENCE
507 | | | | OID oid 1.3.6.1.2.1.1.3.0
508 | | | | TIMETICKS int 638085796
509
510=back
511
512=cut
513
514# reverse enum, very slow and ugly hack
515sub _re {
516 my ($export_tag, $value) = @_;
517
518 for my $symbol (@{ $EXPORT_TAGS{$export_tag} }) {
519 $value == eval $symbol
520 and return $symbol;
521 }
522
523 "($value)"
524}
525
526$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT);
527
528sub _ber_dump {
529 my ($ber, $profile, $indent) = @_;
530
531 if (my $seq = ber_is_seq $ber) {
532 printf "%sSEQUENCE\n", $indent;
533 &_ber_dump ($_, $profile, "$indent| ")
534 for @$seq;
535 } else {
536 my $asn = $ber->[BER_CLASS] == ASN_UNIVERSAL;
537
538 my $class = _re const_asn_class => $ber->[BER_CLASS];
539 my $tag = $asn ? _re const_asn_tag => $ber->[BER_TAG] : $ber->[BER_TAG];
540 my $type = _re const_ber_type => $profile->get ($ber->[BER_CLASS], $ber->[BER_TAG]);
541 my $data = $ber->[BER_DATA];
542
543 if ($profile == $SNMP_PROFILE and $ber->[BER_CLASS] == ASN_APPLICATION) {
544 $tag = _re const_snmp => $ber->[BER_TAG];
545 } elsif (!$asn) {
546 $tag = "$class ($tag)";
547 }
548
549 $class =~ s/^ASN_//;
550 $tag =~ s/^(ASN_|SNMP_)//;
551 $type =~ s/^BER_TYPE_//;
552
553 if ($ber->[BER_FLAGS]) {
554 printf "$indent%-16.16s\n", $tag;
555 &_ber_dump ($_, $profile, "$indent| ")
556 for @$data;
557 } else {
558 if ($data =~ y/\x20-\x7e//c / (length $data || 1) > 0.2 or $data =~ /\x00./s) {
559 # assume binary
560 $data = unpack "H*", $data;
561 } else {
562 $data =~ s/[^\x20-\x7e]/./g;
563 $data = "\"$data\"" if $tag =~ /string/i || !length $data;
564 }
565
566 substr $data, 40, 1e9, "..." if 40 < length $data;
567
568 printf "$indent%-16.16s %-6.6s %s\n", $tag, lc $type, $data;
569 }
570 }
571}
572
573sub ber_dump($;$$) {
574 _ber_dump $_[0], $_[1] || $DEFAULT_PROFILE, $_[2];
575}
454 576
455=head1 PROFILES 577=head1 PROFILES
456 578
457While any BER data can be correctly encoded and decoded out of the box, it 579While any BER data can be correctly encoded and decoded out of the box, it
458can be inconvenient to have to manually decode some values into a "better" 580can be inconvenient to have to manually decode some values into a "better"
… …
519 641
520Returns the BER type mapped to the given C<$class>/C<$tag> combination. 642Returns the BER type mapped to the given C<$class>/C<$tag> combination.
521 643
522=back 644=back
523 645
524=head2 BER TYPES 646=head2 BER Types
525 647
526This lists the predefined BER types - you can map any C<CLASS>/C<TAG> 648This lists the predefined BER types. BER types are formatters used
527combination to any C<BER_TYPE_*>. 649internally to format and encode BER values. You can assign any C<BER_TYPE>
650to any C<CLASS>/C<TAG> combination tgo change how that tag is decoded or
651encoded.
528 652
529=over 653=over
530 654
531=item C<BER_TYPE_BYTES> 655=item C<BER_TYPE_BYTES>
532 656
… …
612 $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT); 736 $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT);
613 $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT); 737 $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT);
614 $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_IPADDRESS); 738 $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_IPADDRESS);
615 $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT); 739 $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT);
616 740
617=cut
618
619our $DEFAULT_PROFILE = new Convert::BER::XS::Profile;
620
621$DEFAULT_PROFILE->_set_default;
622
623# additional SNMP application types
624our $SNMP_PROFILE = new Convert::BER::XS::Profile;
625
626$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_IPADDRESS , BER_TYPE_IPADDRESS);
627$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER32 , BER_TYPE_INT);
628$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT);
629$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT);
630$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_IPADDRESS);
631$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT);
632
6331;
634
635=head2 LIMITATIONS/NOTES 741=head2 LIMITATIONS/NOTES
636 742
637This module can only en-/decode 64 bit signed and unsigned integers, and 743This module can only en-/decode 64 bit signed and unsigned integers, and
638only when your perl supports those. 744only when your perl supports those. So no UUID OIDs for now (unless you
745map the C<OBJECT IDENTIFIER> tag to something other than C<BER_TYPE_OID>).
639 746
640This module does not generally care about ranges, i.e. it will happily 747This module does not generally care about ranges, i.e. it will happily
641de-/encode 64 bit integers into an C<ASN_INTEGER> value, or a negative 748de-/encode 64 bit integers into an C<ASN_INTEGER> value, or a negative
642number into an C<SNMP_COUNTER64>. 749number into an C<SNMP_COUNTER64>.
643 750
644OBJECT IDENTIFIEERs cannot have unlimited length, although the limit is 751OBJECT IDENTIFIEERs cannot have unlimited length, although the limit is
645much larger than e.g. the one imposed by SNMP or other protocols,a nd is 752much larger than e.g. the one imposed by SNMP or other protocols, and is
646about 4kB. 753about 4kB.
647 754
648Indefinite length encoding is not supported. 755Indefinite length encoding is not supported.
649 756
650Constructed strings are decoded just fine, but there should be a way to 757Constructed strings are decoded just fine, but there should be a way to
651join them for convenience. 758join them for convenience.
652 759
653REAL values are not supported and will currently croak. 760REAL values are not supported and will currently croak.
654 761
655The encoder and decoder tend to accept more formats than should be 762The encoder and decoder tend to accept more formats than should be
656strictly supported. 763strictly supported - security sensitive applications are strongly advised
764to review the code first.
657 765
658This module has undergone little to no testing so far. 766This module has undergone little to no testing so far.
659 767
660=head2 ITHREADS SUPPORT 768=head2 ITHREADS SUPPORT
661 769
… …
667 Marc Lehmann <schmorp@schmorp.de> 775 Marc Lehmann <schmorp@schmorp.de>
668 http://software.schmorp.de/pkg/Convert-BER-XS 776 http://software.schmorp.de/pkg/Convert-BER-XS
669 777
670=cut 778=cut
671 779
7801;
781

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