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Comparing Convert-BER-XS/XS.pm (file contents):
Revision 1.25 by root, Sat Apr 20 15:23:26 2019 UTC vs.
Revision 1.58 by root, Sat Apr 27 14:54:40 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, # constructed, 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";
100 103
101=item C<:const_index> 104=item C<:const_index>
102 105
103The BER tuple array index constants: 106The BER tuple array index constants:
104 107
105 BER_CLASS BER_TAG BER_CONSTRUCTED 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
134 137
135Constants only relevant to SNMP. These are the tag values used by SNMP in 138Constants only relevant to SNMP. These are the tag values used by SNMP in
136the C<ASN_APPLICATION> namespace and have the exact numerical value as in 139the C<ASN_APPLICATION> namespace and have the exact numerical value as in
137BER/RFC 2578. 140BER/RFC 2578.
138 141
139 SNMP_IPADDRESS SNMP_COUNTER32 SNMP_UNSIGNED32 SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64 142 SNMP_IPADDRESS SNMP_COUNTER32 SNMP_UNSIGNED32 SNMP_GAUGE32
143 SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64
140 144
141=item C<:decode> 145=item C<:decode>
142 146
143C<ber_decode> and the match helper functions: 147C<ber_decode> and the match helper functions:
144 148
149 ber_decode ber-decode_prefix
145 ber_decode 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
146 152
147=item C<:encode> 153=item C<:encode>
148 154
149C<ber_encode> and the construction helper functions: 155C<ber_encode> and the construction helper functions:
150 156
151 ber_encode ber_int 157 ber_encode
158 ber_int
152 159
153=back 160=back
154 161
155=head2 ASN.1/BER/DER/... BASICS 162=head2 ASN.1/BER/DER/... BASICS
156 163
157ASN.1 is a strange language that can be used to describe protocols and 164ASN.1 is a strange language that can be used to describe protocols and
158data structures. It supports various mappings to JSON, XML, but most 165data structures. It supports various mappings to JSON, XML, but most
159importantly, to a various binary encodings such as BER, that is the topic 166importantly, to a various binary encodings such as BER, that is the topic
160of this module, and is used in SNMP or LDAP for example. 167of this module, and is used in SNMP, LDAP or X.509 for example.
161 168
162While ASN.1 defines a schema that is useful to interpret encoded data, 169While ASN.1 defines a schema that is useful to interpret encoded data,
163the BER encoding is actually somewhat self-describing: you might not know 170the BER encoding is actually somewhat self-describing: you might not know
164whether something is a string or a number or a sequence or something else, 171whether something is a string or a number or a sequence or something else,
165but you can nevertheless decode the overall structure, even if you end up 172but you can nevertheless decode the overall structure, even if you end up
182=head2 DECODED BER REPRESENTATION 189=head2 DECODED BER REPRESENTATION
183 190
184This module represents every BER value as a 4-element tuple (actually an 191This module represents every BER value as a 4-element tuple (actually an
185array-reference): 192array-reference):
186 193
187 [CLASS, TAG, CONSTRUCTED, DATA] 194 [CLASS, TAG, FLAGS, DATA]
188 195
189For example: 196For example:
190 197
191 [ASN_UNIVERSAL, ASN_INTEGER, 0, 177] # the integer 177 198 [ASN_UNIVERSAL, ASN_INTEGER, 0, 177] # the integer 177
192 [ASN_UNIVERSAL, ASN_OCTET_STRING, 0, "john"] # the string "john" 199 [ASN_UNIVERSAL, ASN_OCTET_STRING, 0, "john"] # the string "john"
193 [ASN_UNIVERSAL, ASN_OID, 0, "1.3.6.133"] # some OID 200 [ASN_UNIVERSAL, ASN_OID, 0, "1.3.6.133"] # some OID
194 [ASN_UNIVERSAL, ASN_SEQUENCE, 1, [ [ASN_UNIVERSAL... # a sequence 201 [ASN_UNIVERSAL, ASN_SEQUENCE, 1, [ [ASN_UNIVERSAL... # a sequence
195 202
196To avoid non-descriptive hardcoded array index numbers, this module 203To avoid non-descriptive hardcoded array index numbers, this module
197defines symbolic constants to access these members: C<BER_CLASS>, 204defines symbolic constants to access these members: C<BER_CLASS>,
198C<BER_TAG>, C<BER_CONSTRUCTED> and C<BER_DATA>. 205C<BER_TAG>, C<BER_FLAGS> and C<BER_DATA>.
199 206
200Also, the first three members are integers with a little caveat: for 207Also, the first three members are integers with a little caveat: for
201performance reasons, these are readonly and shared, so you must not modify 208performance reasons, these are readonly and shared, so you must not modify
202them (increment, assign to them etc.) in any way. You may modify the 209them (increment, assign to them etc.) in any way. You may modify the
203I<DATA> member, and you may re-assign the array itself, e.g.: 210I<DATA> member, and you may re-assign the array itself, e.g.:
204 211
205 $ber = ber_decode $binbuf; 212 $ber = ber_decode $binbuf;
206 213
207 # the following is NOT legal: 214 # the following is NOT legal:
208 $ber->[BER_CLASS] = ASN_PRIVATE; # ERROR, CLASS/TAG/CONSTRUCTED are READ ONLY(!) 215 $ber->[BER_CLASS] = ASN_PRIVATE; # ERROR, CLASS/TAG/FLAGS are READ ONLY(!)
209 216
210 # but all of the following are fine: 217 # but all of the following are fine:
211 $ber->[BER_DATA] = "string"; 218 $ber->[BER_DATA] = "string";
212 $ber->[BER_DATA] = [ASN_UNIVERSAL, ASN_INTEGER, 0, 123]; 219 $ber->[BER_DATA] = [ASN_UNIVERSAL, ASN_INTEGER, 0, 123];
213 @$ber = (ASN_APPLICATION, SNMP_TIMETICKS, 0, 1000); 220 @$ber = (ASN_APPLICATION, SNMP_TIMETICKS, 0, 1000);
231 238
232The most common tags in SNMP's C<ASN_APPLICATION> namespace are 239The most common tags in SNMP's C<ASN_APPLICATION> namespace are
233C<SNMP_COUNTER32>, C<SNMP_UNSIGNED32>, C<SNMP_TIMETICKS> and 240C<SNMP_COUNTER32>, C<SNMP_UNSIGNED32>, C<SNMP_TIMETICKS> and
234C<SNMP_COUNTER64>. 241C<SNMP_COUNTER64>.
235 242
236The I<CONSTRUCTED> flag is really just a boolean - if it is false, 243The I<FLAGS> value is really just a boolean at this time (but might
237the value is "primitive" and contains no subvalues, kind of like a 244get extended) - if it is C<0>, the value is "primitive" and contains
238non-reference perl scalar. If it is true, then the value is "constructed" 245no subvalues, kind of like a non-reference perl scalar. If it is C<1>,
239which just means it contains a list of subvalues which this module will 246then the value is "constructed" which just means it contains a list of
240en-/decode as BER tuples themselves. 247subvalues which this module will en-/decode as BER tuples themselves.
241 248
242The I<DATA> value is either a reference to an array of further tuples (if 249The I<DATA> value is either a reference to an array of further tuples
243the value is I<CONSTRUCTED>), some decoded representation of the value, 250(if the value is I<FLAGS>), some decoded representation of the value, if
244if this module knows how to decode it (e.g. for the integer types above) 251this module knows how to decode it (e.g. for the integer types above) or
245or a binary string with the raw octets if this module doesn't know how to 252a binary string with the raw octets if this module doesn't know how to
246interpret the namespace/tag. 253interpret the namespace/tag.
247 254
248Thus, you can always decode a BER data structure and at worst you get a 255Thus, you can always decode a BER data structure and at worst you get a
249string in place of some nice decoded value. 256string in place of some nice decoded value.
250 257
252 259
253=head2 DECODING AND ENCODING 260=head2 DECODING AND ENCODING
254 261
255=over 262=over
256 263
257=item $tuple = ber_decoded $bindata[, $profile] 264=item $tuple = ber_decode $bindata[, $profile]
258 265
259Decodes binary BER data in C<$bindata> and returns the resulting BER 266Decodes binary BER data in C<$bindata> and returns the resulting BER
260tuple. Croaks on any decoding error, so the returned C<$tuple> is always 267tuple. Croaks on any decoding error, so the returned C<$tuple> is always
261valid. 268valid.
262 269
275 282
276Example: as above, but use the provided SNMP profile. 283Example: as above, but use the provided SNMP profile.
277 284
278 $tuple = ber_encode $data, $Convert::BER::XS::SNMP_PROFILE; 285 $tuple = ber_encode $data, $Convert::BER::XS::SNMP_PROFILE;
279 286
287=item ($tuple, $bytes) = ber_decode_prefix $bindata[, $profile]
288
289Works like C<ber_decode>, except it doesn't croak when there is data after
290the BER data, but instead returns the decoded value and the number of
291bytes it decoded.
292
293This is useful when you have BER data at the start of a buffer and other
294data after, and you need to find the length.
295
296Also, since BER is self-delimited, this can be used to decode multiple BER
297values joined together.
298
280=item $bindata = ber_encode $tuple[, $profile] 299=item $bindata = ber_encode $tuple[, $profile]
281 300
282Encodes the BER tuple into a BER/DER data structure. AS with 301Encodes the BER tuple into a BER/DER data structure. As with
283Cyber_decode>, an optional profile can be given. 302Cyber_decode>, an optional profile can be given.
303
304The encoded data should be both BER and DER ("shortest form") compliant
305unless the input says otherwise (e.g. it uses constructed strings).
284 306
285=back 307=back
286 308
287=head2 HELPER FUNCTIONS 309=head2 HELPER FUNCTIONS
288 310
300a ease-of-use exception, they usually also accept C<undef> instead of a 322a ease-of-use exception, they usually also accept C<undef> instead of a
301tuple reference, in which case they silently fail to match. 323tuple reference, in which case they silently fail to match.
302 324
303=over 325=over
304 326
305=item $bool = ber_is $tuple, $class, $tag, $constructed, $data 327=item $bool = ber_is $tuple, $class, $tag, $flags, $data
306 328
307This takes a BER C<$tuple> and matches its elements against the provided 329This takes a BER C<$tuple> and matches its elements against the provided
308values, all of which are optional - values that are either missing or 330values, all of which are optional - values that are either missing or
309C<undef> will be ignored, the others will be matched exactly (e.g. as if 331C<undef> will be ignored, the others will be matched exactly (e.g. as if
310you used C<==> or C<eq> (for C<$data>)). 332you used C<==> or C<eq> (for C<$data>)).
387use common::sense; 409use common::sense;
388 410
389use XSLoader (); 411use XSLoader ();
390use Exporter qw(import); 412use Exporter qw(import);
391 413
414use Carp ();
415
392our $VERSION; 416our $VERSION;
393 417
394BEGIN { 418BEGIN {
395 $VERSION = 0.8; 419 $VERSION = 1.2;
396 XSLoader::load __PACKAGE__, $VERSION; 420 XSLoader::load __PACKAGE__, $VERSION;
397} 421}
398 422
399our %EXPORT_TAGS = ( 423our %EXPORT_TAGS = (
400 const_index => [qw( 424 const_index => [qw(
401 BER_CLASS BER_TAG BER_CONSTRUCTED BER_DATA 425 BER_CLASS BER_TAG BER_FLAGS BER_DATA
402 )], 426 )],
427 const_asn_class => [qw(
428 ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE
429 )],
403 const_asn => [qw( 430 const_asn_tag => [qw(
404 ASN_BOOLEAN ASN_INTEGER ASN_BIT_STRING ASN_OCTET_STRING ASN_NULL ASN_OBJECT_IDENTIFIER 431 ASN_BOOLEAN ASN_INTEGER ASN_BIT_STRING ASN_OCTET_STRING ASN_NULL ASN_OID ASN_OBJECT_IDENTIFIER
405 ASN_OBJECT_DESCRIPTOR ASN_OID ASN_EXTERNAL ASN_REAL ASN_SEQUENCE ASN_ENUMERATED 432 ASN_OBJECT_DESCRIPTOR ASN_EXTERNAL ASN_REAL ASN_SEQUENCE ASN_ENUMERATED
406 ASN_EMBEDDED_PDV ASN_UTF8_STRING ASN_RELATIVE_OID ASN_SET ASN_NUMERIC_STRING 433 ASN_EMBEDDED_PDV ASN_UTF8_STRING ASN_RELATIVE_OID ASN_SET ASN_NUMERIC_STRING
407 ASN_PRINTABLE_STRING ASN_TELETEX_STRING ASN_T61_STRING ASN_VIDEOTEX_STRING ASN_IA5_STRING 434 ASN_PRINTABLE_STRING ASN_TELETEX_STRING ASN_T61_STRING ASN_VIDEOTEX_STRING ASN_IA5_STRING
408 ASN_ASCII_STRING ASN_UTC_TIME ASN_GENERALIZED_TIME ASN_GRAPHIC_STRING ASN_VISIBLE_STRING 435 ASN_ASCII_STRING ASN_UTC_TIME ASN_GENERALIZED_TIME ASN_GRAPHIC_STRING ASN_VISIBLE_STRING
409 ASN_ISO646_STRING ASN_GENERAL_STRING ASN_UNIVERSAL_STRING ASN_CHARACTER_STRING ASN_BMP_STRING 436 ASN_ISO646_STRING ASN_GENERAL_STRING ASN_UNIVERSAL_STRING ASN_CHARACTER_STRING ASN_BMP_STRING
410
411 ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE
412 )], 437 )],
413 const_ber_type => [qw( 438 const_ber_type => [qw(
414 BER_TYPE_BYTES BER_TYPE_UTF8 BER_TYPE_UCS2 BER_TYPE_UCS4 BER_TYPE_INT 439 BER_TYPE_BYTES BER_TYPE_UTF8 BER_TYPE_UCS2 BER_TYPE_UCS4 BER_TYPE_INT
415 BER_TYPE_OID BER_TYPE_RELOID BER_TYPE_NULL BER_TYPE_BOOL BER_TYPE_REAL 440 BER_TYPE_OID BER_TYPE_RELOID BER_TYPE_NULL BER_TYPE_BOOL BER_TYPE_REAL
416 BER_TYPE_IPADDRESS BER_TYPE_CROAK 441 BER_TYPE_IPADDRESS BER_TYPE_CROAK
417 )], 442 )],
418 const_snmp => [qw( 443 const_snmp => [qw(
419 SNMP_IPADDRESS SNMP_COUNTER32 SNMP_UNSIGNED32 SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64 444 SNMP_IPADDRESS SNMP_COUNTER32 SNMP_GAUGE32 SNMP_UNSIGNED32
445 SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64
420 )], 446 )],
421 decode => [qw( 447 decode => [qw(
422 ber_decode 448 ber_decode ber_decode_prefix
423 ber_is ber_is_seq ber_is_int ber_is_oid 449 ber_is ber_is_seq ber_is_int ber_is_oid
450 ber_dump
424 )], 451 )],
425 encode => [qw( 452 encode => [qw(
426 ber_encode 453 ber_encode
427 ber_int 454 ber_int
428 )], 455 )],
429); 456);
430 457
431our @EXPORT_OK = map @$_, values %EXPORT_TAGS; 458our @EXPORT_OK = map @$_, values %EXPORT_TAGS;
432 459
433$EXPORT_TAGS{all} = \@EXPORT_OK; 460$EXPORT_TAGS{all} = \@EXPORT_OK;
461$EXPORT_TAGS{const_asn} = [map @{ $EXPORT_TAGS{$_} }, qw(const_asn_class const_asn_tag)];
434$EXPORT_TAGS{const} = [map @{ $EXPORT_TAGS{$_} }, qw(const_index const_asn)]; 462$EXPORT_TAGS{const} = [map @{ $EXPORT_TAGS{$_} }, qw(const_index const_asn)];
435use Data::Dump; ddx \%EXPORT_TAGS; 463
464our $DEFAULT_PROFILE = new Convert::BER::XS::Profile;
465
466$DEFAULT_PROFILE->_set_default;
467
468# additional SNMP application types
469our $SNMP_PROFILE = new Convert::BER::XS::Profile;
470
471$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_IPADDRESS , BER_TYPE_IPADDRESS);
472$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER32 , BER_TYPE_INT);
473$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT);
474$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT);
475
476# decodes REAL values according to ECMA-63
477# this is pretty strict, except it doesn't catch -0.
478# I don't have access to ISO 6093 (or BS 6727, or ANSI X.3-42)), so this is all guesswork.
479sub _decode_real_decimal {
480 my ($format, $val) = @_;
481
482 $val =~ y/,/./; # probably not in ISO-6093
483
484 if ($format == 1) {
485 $val =~ /^ \ * [+-]? [0-9]+ \z/x
486 or Carp::croak "BER_TYPE_REAL NR1 value not in NR1 format ($val) (X.690 8.5.8)";
487 } elsif ($format == 2) {
488 $val =~ /^ \ * [+-]? (?: [0-9]+\.[0-9]* | [0-9]*\.[0-9]+ ) \z/x
489 or Carp::croak "BER_TYPE_REAL NR2 value not in NR2 format ($val) (X.690 8.5.8)";
490 } elsif ($format == 3) {
491 $val =~ /^ \ * [+-] (?: [0-9]+\.[0-9]* | [0-9]*\.[0-9]+ ) [eE] [+-]? [0-9]+ \z/x
492 or Carp::croak "BER_TYPE_REAL NR3 value not in NR3 format ($val) (X.690 8.5.8)";
493 } else {
494 Carp::croak "BER_TYPE_REAL illegal decimal numerical representation format $format";
495 }
496
497 $val
498}
499
500# this is a mess, but perl's support for floating point formatting is nearly nonexistant
501sub _encode_real_decimal {
502 my ($val, $nvdig) = @_;
503
504 $val = sprintf "%.*G", $nvdig + 1, $val;
505
506 if ($val =~ /E/) {
507 $val =~ s/E(?=[^+-])/E+/;
508 $val =~ s/E/.E/ if $val !~ /\./;
509 $val =~ s/^/+/ unless $val =~ /^-/;
510
511 return "\x03$val" # NR3
512 }
513
514 $val =~ /\./
515 ? "\x02$val" # NR2
516 : "\x01$val" # NR1
517}
518
519=head2 DEBUGGING
520
521To aid debugging, you can call the C<ber_dump> function to print a "nice"
522representation to STDOUT.
523
524=over
525
526=item ber_dump $tuple[, $profile[, $prefix]]
527
528In addition to specifying the BER C<$tuple> to dump, you can also specify
529a C<$profile> and a C<$prefix> string that is printed in front of each line.
530
531If C<$profile> is C<$Convert::BER::XS::SNMP_PROFILE>, then C<ber_dump>
532will try to improve its output for SNMP data.
533
534The output usually contains three columns, the "human readable" tag, the
535BER type used to decode it, and the data value.
536
537This function is somewhat slow and uses a number of heuristics and tricks,
538so it really is only suitable for debug prints.
539
540Example output:
541
542 SEQUENCE
543 | OCTET_STRING bytes 800063784300454045045400000001
544 | OCTET_STRING bytes
545 | CONTEXT (7) CONSTRUCTED
546 | | INTEGER int 1058588941
547 | | INTEGER int 0
548 | | INTEGER int 0
549 | | SEQUENCE
550 | | | SEQUENCE
551 | | | | OID oid 1.3.6.1.2.1.1.3.0
552 | | | | TIMETICKS int 638085796
553
554=back
555
556=cut
557
558# reverse enum, very slow and ugly hack
559sub _re {
560 my ($export_tag, $value) = @_;
561
562 for my $symbol (@{ $EXPORT_TAGS{$export_tag} }) {
563 $value == eval $symbol
564 and return $symbol;
565 }
566
567 "($value)"
568}
569
570$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT);
571
572sub _ber_dump {
573 my ($ber, $profile, $indent) = @_;
574
575 if (my $seq = ber_is_seq $ber) {
576 printf "%sSEQUENCE\n", $indent;
577 &_ber_dump ($_, $profile, "$indent| ")
578 for @$seq;
579 } else {
580 my $asn = $ber->[BER_CLASS] == ASN_UNIVERSAL;
581
582 my $class = _re const_asn_class => $ber->[BER_CLASS];
583 my $tag = $asn ? _re const_asn_tag => $ber->[BER_TAG] : $ber->[BER_TAG];
584 my $type = _re const_ber_type => $profile->get ($ber->[BER_CLASS], $ber->[BER_TAG]);
585 my $data = $ber->[BER_DATA];
586
587 if ($profile == $SNMP_PROFILE and $ber->[BER_CLASS] == ASN_APPLICATION) {
588 $tag = _re const_snmp => $ber->[BER_TAG];
589 } elsif (!$asn) {
590 $tag = "$class ($tag)";
591 }
592
593 $class =~ s/^ASN_//;
594 $tag =~ s/^(ASN_|SNMP_)//;
595 $type =~ s/^BER_TYPE_//;
596
597 if ($ber->[BER_FLAGS]) {
598 printf "$indent%-16.16s\n", $tag;
599 &_ber_dump ($_, $profile, "$indent| ")
600 for @$data;
601 } else {
602 if ($data =~ y/\x20-\x7e//c / (length $data || 1) > 0.2 or $data =~ /\x00./s) {
603 # assume binary
604 $data = unpack "H*", $data;
605 } else {
606 $data =~ s/[^\x20-\x7e]/./g;
607 $data = "\"$data\"" if $tag =~ /string/i || !length $data;
608 }
609
610 substr $data, 40, 1e9, "..." if 40 < length $data;
611
612 printf "$indent%-16.16s %-6.6s %s\n", $tag, lc $type, $data;
613 }
614 }
615}
616
617sub ber_dump($;$$) {
618 _ber_dump $_[0], $_[1] || $DEFAULT_PROFILE, $_[2];
619}
436 620
437=head1 PROFILES 621=head1 PROFILES
438 622
439While any BER data can be correctly encoded and decoded out of the box, it 623While any BER data can be correctly encoded and decoded out of the box, it
440can be inconvenient to have to manually decode some values into a "better" 624can be inconvenient to have to manually decode some values into a "better"
501 685
502Returns the BER type mapped to the given C<$class>/C<$tag> combination. 686Returns the BER type mapped to the given C<$class>/C<$tag> combination.
503 687
504=back 688=back
505 689
506=head2 BER TYPES 690=head2 BER Types
507 691
508This lists the predefined BER types - you can map any C<CLASS>/C<TAG> 692This lists the predefined BER types. BER types are formatters used
509combination to any C<BER_TYPE_*>. 693internally to format and encode BER values. You can assign any C<BER_TYPE>
694to any C<CLASS>/C<TAG> combination tgo change how that tag is decoded or
695encoded.
510 696
511=over 697=over
512 698
513=item C<BER_TYPE_BYTES> 699=item C<BER_TYPE_BYTES>
514 700
580C<BER_TYPE_BYTES>. When you don't want that but instead prefer a hard 766C<BER_TYPE_BYTES>. When you don't want that but instead prefer a hard
581error for some types, then C<BER_TYPE_CROAK> is for you. 767error for some types, then C<BER_TYPE_CROAK> is for you.
582 768
583=back 769=back
584 770
585=cut 771=head2 Example Profile
586 772
587our $DEFAULT_PROFILE = new Convert::BER::XS::Profile; 773The following creates a profile suitable for SNMP - it's exactly identical
774to the C<$Convert::BER::XS::SNMP_PROFILE> profile.
775
588our $SNMP_PROFILE = new Convert::BER::XS::Profile; 776 our $SNMP_PROFILE = new Convert::BER::XS::Profile;
589 777
590# additional SNMP application types
591$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_IPADDRESS , BER_TYPE_IPADDRESS); 778 $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_IPADDRESS , BER_TYPE_IPADDRESS);
592$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER32 , BER_TYPE_INT); 779 $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER32 , BER_TYPE_INT);
593$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT); 780 $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT);
594$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT); 781 $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT);
595$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_IPADDRESS); 782 $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_BYTES);
596$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT); 783 $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT);
597
598$DEFAULT_PROFILE->_set_default;
599
6001;
601 784
602=head2 LIMITATIONS/NOTES 785=head2 LIMITATIONS/NOTES
603 786
604This module can only en-/decode 64 bit signed and unsigned integers, and 787This module can only en-/decode 64 bit signed and unsigned
605only when your perl supports those. 788integers/tags/lengths, and only when your perl supports those. So no UUID
789OIDs for now (unless you map the C<OBJECT IDENTIFIER> tag to something
790other than C<BER_TYPE_OID>).
606 791
607This module does not generally care about ranges, i.e. it will happily 792This module does not generally care about ranges, i.e. it will happily
608de-/encode 64 bit integers into an C<ASN_INTEGER> value, or a negative 793de-/encode 64 bit integers into an C<SNMP_UNSIGNED32> value, or a negative
609number into an C<SNMP_COUNTER64>. 794number into an C<SNMP_COUNTER64>.
610 795
611OBJECT IDENTIFIEERs cannot have unlimited length, although the limit is 796OBJECT IDENTIFIEERs cannot have unlimited length, although the limit is
612much larger than e.g. the one imposed by SNMP or other protocols,a nd is 797much larger than e.g. the one imposed by SNMP or other protocols, and is
613about 4kB. 798about 4kB.
614 799
615REAL values are not supported and will currently croak. 800Constructed strings are decoded just fine, but there should be a way to
801join them for convenience.
616 802
617This module has undergone little to no testing so far. 803REAL values will always be encoded in decimal form and ssometimes is
804forced into a perl "NV" type, potentially losing precision.
618 805
619=head2 ITHREADS SUPPORT 806=head2 ITHREADS SUPPORT
620 807
621This module is unlikely to work when the (officially discouraged) ithreads 808This module is unlikely to work in any other than the loading thread when
622are in use. 809the (officially discouraged) ithreads are in use.
623 810
624=head1 AUTHOR 811=head1 AUTHOR
625 812
626 Marc Lehmann <schmorp@schmorp.de> 813 Marc Lehmann <schmorp@schmorp.de>
627 http://software.schmorp.de/pkg/Convert-BER-XS 814 http://software.schmorp.de/pkg/Convert-BER-XS
628 815
629=cut 816=cut
630 817
8181;
819

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