… | |
… | |
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 | |
103 | The BER tuple array index constants: |
106 | The 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 | |
109 | ASN class values (these are C<0>, C<1>, C<2> and C<3>, respectively - |
112 | ASN class values (these are C<0>, C<1>, C<2> and C<3>, respectively - |
110 | exactly thw two topmost bits from the identifier octet shifted 6 bits to |
113 | exactly thw two topmost bits from the identifier octet shifted 6 bits to |
… | |
… | |
113 | ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE |
116 | ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE |
114 | |
117 | |
115 | ASN tag values (some of which are aliases, such as C<ASN_OID>). Their |
118 | ASN tag values (some of which are aliases, such as C<ASN_OID>). Their |
116 | numerical value corresponds exactly to the numbers used in BER/X.690. |
119 | numerical 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 | |
135 | Constants only relevant to SNMP. These are the tag values used by SNMP in |
138 | Constants only relevant to SNMP. These are the tag values used by SNMP in |
136 | the C<ASN_APPLICATION> namespace and have the exact numerical value as in |
139 | the C<ASN_APPLICATION> namespace and have the exact numerical value as in |
137 | BER/RFC 2578. |
140 | BER/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 | |
143 | C<ber_decode> and the match helper functions: |
147 | C<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 | |
149 | C<ber_encode> and the construction helper functions: |
155 | C<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 | |
… | |
… | |
182 | =head2 DECODED BER REPRESENTATION |
189 | =head2 DECODED BER REPRESENTATION |
183 | |
190 | |
184 | This module represents every BER value as a 4-element tuple (actually an |
191 | This module represents every BER value as a 4-element tuple (actually an |
185 | array-reference): |
192 | array-reference): |
186 | |
193 | |
187 | [CLASS, TAG, CONSTRUCTED, DATA] |
194 | [CLASS, TAG, FLAGS, DATA] |
188 | |
195 | |
189 | For example: |
196 | For 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 | |
196 | To avoid non-descriptive hardcoded array index numbers, this module |
203 | To avoid non-descriptive hardcoded array index numbers, this module |
197 | defines symbolic constants to access these members: C<BER_CLASS>, |
204 | defines symbolic constants to access these members: C<BER_CLASS>, |
198 | C<BER_TAG>, C<BER_CONSTRUCTED> and C<BER_DATA>. |
205 | C<BER_TAG>, C<BER_FLAGS> and C<BER_DATA>. |
199 | |
206 | |
200 | Also, the first three members are integers with a little caveat: for |
207 | Also, the first three members are integers with a little caveat: for |
201 | performance reasons, these are readonly and shared, so you must not modify |
208 | performance reasons, these are readonly and shared, so you must not modify |
202 | them (increment, assign to them etc.) in any way. You may modify the |
209 | them (increment, assign to them etc.) in any way. You may modify the |
203 | I<DATA> member, and you may re-assign the array itself, e.g.: |
210 | I<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 | |
232 | The most common tags in SNMP's C<ASN_APPLICATION> namespace are |
239 | The most common tags in SNMP's C<ASN_APPLICATION> namespace are |
233 | C<SNMP_COUNTER32>, C<SNMP_UNSIGNED32>, C<SNMP_TIMETICKS> and |
240 | C<SNMP_COUNTER32>, C<SNMP_UNSIGNED32>, C<SNMP_TIMETICKS> and |
234 | C<SNMP_COUNTER64>. |
241 | C<SNMP_COUNTER64>. |
235 | |
242 | |
236 | The I<CONSTRUCTED> flag is really just a boolean - if it is false, |
243 | The I<FLAGS> value is really just a boolean at this time (but might |
237 | the value is "primitive" and contains no subvalues, kind of like a |
244 | get extended) - if it is C<0>, the value is "primitive" and contains |
238 | non-reference perl scalar. If it is true, then the value is "constructed" |
245 | no subvalues, kind of like a non-reference perl scalar. If it is C<1>, |
239 | which just means it contains a list of subvalues which this module will |
246 | then the value is "constructed" which just means it contains a list of |
240 | en-/decode as BER tuples themselves. |
247 | subvalues which this module will en-/decode as BER tuples themselves. |
241 | |
248 | |
242 | The I<DATA> value is either a reference to an array of further tuples (if |
249 | The I<DATA> value is either a reference to an array of further tuples |
243 | the value is I<CONSTRUCTED>), some decoded representation of the value, |
250 | (if the value is I<FLAGS>), some decoded representation of the value, if |
244 | if this module knows how to decode it (e.g. for the integer types above) |
251 | this module knows how to decode it (e.g. for the integer types above) or |
245 | or a binary string with the raw octets if this module doesn't know how to |
252 | a binary string with the raw octets if this module doesn't know how to |
246 | interpret the namespace/tag. |
253 | interpret the namespace/tag. |
247 | |
254 | |
248 | Thus, you can always decode a BER data structure and at worst you get a |
255 | Thus, you can always decode a BER data structure and at worst you get a |
249 | string in place of some nice decoded value. |
256 | string 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[, $profile] |
258 | |
265 | |
259 | Decodes binary BER data in C<$bindata> and returns the resulting BER |
266 | Decodes binary BER data in C<$bindata> and returns the resulting BER |
260 | tuple. Croaks on any decoding error, so the returned C<$tuple> is always |
267 | tuple. Croaks on any decoding error, so the returned C<$tuple> is always |
261 | valid. |
268 | valid. |
262 | |
269 | |
… | |
… | |
275 | |
282 | |
276 | Example: as above, but use the provided SNMP profile. |
283 | Example: 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 | |
|
|
289 | Works like C<ber_decode>, except it doesn't croak when there is data after |
|
|
290 | the BER data, but instead returns the decoded value and the number of |
|
|
291 | bytes it decoded. |
|
|
292 | |
|
|
293 | This is useful when you have BER data at the start of a buffer and other |
|
|
294 | data after, and you need to find the length. |
|
|
295 | |
|
|
296 | Also, since BER is self-delimited, this can be used to decode multiple BER |
|
|
297 | values joined together. |
|
|
298 | |
280 | =item $bindata = ber_encode $tuple[, $profile] |
299 | =item $bindata = ber_encode $tuple[, $profile] |
281 | |
300 | |
282 | Encodes the BER tuple into a BER/DER data structure. AS with |
301 | Encodes the BER tuple into a BER/DER data structure. AS with |
283 | Cyber_decode>, an optional profile can be given. |
302 | Cyber_decode>, an optional profile can be given. |
|
|
303 | |
|
|
304 | The encoded data should be both BER and DER ("shortest form") compliant |
|
|
305 | unless 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 | |
… | |
… | |
300 | a ease-of-use exception, they usually also accept C<undef> instead of a |
322 | a ease-of-use exception, they usually also accept C<undef> instead of a |
301 | tuple reference, in which case they silently fail to match. |
323 | tuple 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, $data |
306 | |
328 | |
307 | This takes a BER C<$tuple> and matches its elements against the provided |
329 | This takes a BER C<$tuple> and matches its elements against the provided |
308 | values, all of which are optional - values that are either missing or |
330 | values, all of which are optional - values that are either missing or |
309 | C<undef> will be ignored, the others will be matched exactly (e.g. as if |
331 | C<undef> will be ignored, the others will be matched exactly (e.g. as if |
310 | you used C<==> or C<eq> (for C<$data>)). |
332 | you used C<==> or C<eq> (for C<$data>)). |
… | |
… | |
390 | use Exporter qw(import); |
412 | use Exporter qw(import); |
391 | |
413 | |
392 | our $VERSION; |
414 | our $VERSION; |
393 | |
415 | |
394 | BEGIN { |
416 | BEGIN { |
395 | $VERSION = 0.8; |
417 | $VERSION = '1.0'; |
396 | XSLoader::load __PACKAGE__, $VERSION; |
418 | XSLoader::load __PACKAGE__, $VERSION; |
397 | } |
419 | } |
398 | |
420 | |
399 | our %EXPORT_TAGS = ( |
421 | our %EXPORT_TAGS = ( |
400 | const_index => [qw( |
422 | const_index => [qw( |
401 | BER_CLASS BER_TAG BER_CONSTRUCTED BER_DATA |
423 | BER_CLASS BER_TAG BER_FLAGS BER_DATA |
402 | )], |
424 | )], |
|
|
425 | const_asn_class => [qw( |
|
|
426 | ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE |
|
|
427 | )], |
403 | const_asn => [qw( |
428 | const_asn_tag => [qw( |
404 | 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 |
405 | 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 |
406 | 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 |
407 | 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 |
408 | 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 |
409 | 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 |
410 | |
|
|
411 | ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE |
|
|
412 | )], |
435 | )], |
413 | const_ber_type => [qw( |
436 | const_ber_type => [qw( |
414 | 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 |
415 | 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 |
416 | BER_TYPE_IPADDRESS BER_TYPE_CROAK |
439 | BER_TYPE_IPADDRESS BER_TYPE_CROAK |
417 | )], |
440 | )], |
418 | const_snmp => [qw( |
441 | const_snmp => [qw( |
419 | SNMP_IPADDRESS SNMP_COUNTER32 SNMP_UNSIGNED32 SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64 |
442 | SNMP_IPADDRESS SNMP_COUNTER32 SNMP_GAUGE32 SNMP_UNSIGNED32 |
|
|
443 | SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64 |
420 | )], |
444 | )], |
421 | decode => [qw( |
445 | decode => [qw( |
422 | ber_decode |
446 | ber_decode ber_decode_prefix |
423 | 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 |
424 | )], |
449 | )], |
425 | encode => [qw( |
450 | encode => [qw( |
426 | ber_encode |
451 | ber_encode |
427 | ber_int |
452 | ber_int |
428 | )], |
453 | )], |
429 | ); |
454 | ); |
430 | |
455 | |
431 | our @EXPORT_OK = map @$_, values %EXPORT_TAGS; |
456 | our @EXPORT_OK = map @$_, values %EXPORT_TAGS; |
432 | |
457 | |
433 | $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)]; |
434 | $EXPORT_TAGS{const} = [map @{ $EXPORT_TAGS{$_} }, qw(const_index const_asn)]; |
460 | $EXPORT_TAGS{const} = [map @{ $EXPORT_TAGS{$_} }, qw(const_index const_asn)]; |
|
|
461 | |
|
|
462 | our $DEFAULT_PROFILE = new Convert::BER::XS::Profile; |
|
|
463 | |
|
|
464 | $DEFAULT_PROFILE->_set_default; |
|
|
465 | |
|
|
466 | # additional SNMP application types |
|
|
467 | our $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 | |
|
|
477 | To aid debugging, you cna call the C<ber_dump> function to print a "nice" |
|
|
478 | representation to STDOUT. |
|
|
479 | |
|
|
480 | =over |
|
|
481 | |
|
|
482 | =item ber_dump $tuple[, $profile[, $prefix]] |
|
|
483 | |
|
|
484 | In addition to specifying the BER C<$tuple> to dump, youc an also specify |
|
|
485 | a C<$profile> and a C<$prefix> string that is printed in front of each line. |
|
|
486 | |
|
|
487 | If C<$profile> is C<$Convert::BER::XS::SNMP_PROFILE>, then C<ber_dump> |
|
|
488 | will try to improve its output for SNMP data. |
|
|
489 | |
|
|
490 | The output usually contains three columns, the "human readable" tag, the |
|
|
491 | BER type used to decode it, and the data value. |
|
|
492 | |
|
|
493 | This function is somewhat slow and uses a number of heuristics and tricks, |
|
|
494 | so it really is only suitable for debug prints. |
|
|
495 | |
|
|
496 | Example output: |
|
|
497 | |
|
|
498 | SEQUENCE |
|
|
499 | | OCTET_STRING bytes 800063784300454045045400000001 |
|
|
500 | | OCTET_STRING bytes |
|
|
501 | | CONTEXT (7) bytes 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 | =cut |
|
|
511 | |
|
|
512 | # reverse enum, very slow and ugly hack |
|
|
513 | sub _re { |
|
|
514 | my ($export_tag, $value) = @_; |
|
|
515 | |
|
|
516 | for my $symbol (@{ $EXPORT_TAGS{$export_tag} }) { |
|
|
517 | $value == eval $symbol |
|
|
518 | and return $symbol; |
|
|
519 | } |
|
|
520 | |
|
|
521 | "($value)" |
|
|
522 | } |
|
|
523 | |
|
|
524 | $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT); |
|
|
525 | |
|
|
526 | sub _ber_dump { |
|
|
527 | my ($ber, $profile, $indent) = @_; |
|
|
528 | |
|
|
529 | if (my $seq = ber_is_seq $ber) { |
|
|
530 | printf "%sSEQUENCE\n", $indent; |
|
|
531 | &_ber_dump ($_, $profile, "$indent| ") |
|
|
532 | for @$seq; |
|
|
533 | } else { |
|
|
534 | my $asn = $ber->[BER_CLASS] == ASN_UNIVERSAL; |
|
|
535 | |
|
|
536 | my $class = _re const_asn_class => $ber->[BER_CLASS]; |
|
|
537 | my $tag = $asn ? _re const_asn_tag => $ber->[BER_TAG] : $ber->[BER_TAG]; |
|
|
538 | my $type = _re const_ber_type => $profile->get ($ber->[BER_CLASS], $ber->[BER_TAG]); |
|
|
539 | my $data = $ber->[BER_DATA]; |
|
|
540 | |
|
|
541 | if ($profile == $SNMP_PROFILE and $ber->[BER_CLASS] == ASN_APPLICATION) { |
|
|
542 | $tag = _re const_snmp => $ber->[BER_TAG]; |
|
|
543 | } elsif (!$asn) { |
|
|
544 | $tag = "$class ($tag)"; |
|
|
545 | } |
|
|
546 | |
|
|
547 | $class =~ s/^ASN_//; |
|
|
548 | $tag =~ s/^(ASN_|SNMP_)//; |
|
|
549 | $type =~ s/^BER_TYPE_//; |
|
|
550 | |
|
|
551 | if ($ber->[BER_FLAGS]) { |
|
|
552 | printf "$indent%-16.16s %-6.6s CONSTRUCTED\n", $tag, lc $type; |
|
|
553 | &_ber_dump ($_, $profile, "$indent| ") |
|
|
554 | for @$data; |
|
|
555 | } else { |
|
|
556 | if ($data =~ y/\x20-\x7e//c / (length $data || 1) > 0.2 or $data =~ /\x00./s) { |
|
|
557 | # assume binary |
|
|
558 | $data = unpack "H*", $data; |
|
|
559 | substr $data, 40, 1e9, "..." if 40 < length $data; |
|
|
560 | } else { |
|
|
561 | $data =~ s/[^\x20-\x7e]/./g; |
|
|
562 | $data = "\"$data\"" if $type =~ /string/i; |
|
|
563 | substr $data, 40, 1e9, "..." if 40 < length $data; |
|
|
564 | } |
|
|
565 | |
|
|
566 | printf "$indent%-16.16s %-6.6s %s\n", $tag, lc $type, $data; |
|
|
567 | } |
|
|
568 | } |
|
|
569 | } |
|
|
570 | |
|
|
571 | sub ber_dump($;$$) { |
|
|
572 | _ber_dump $_[0], $_[1] || $DEFAULT_PROFILE, $_[2]; |
|
|
573 | } |
435 | |
574 | |
436 | =head1 PROFILES |
575 | =head1 PROFILES |
437 | |
576 | |
438 | While any BER data can be correctly encoded and decoded out of the box, it |
577 | While any BER data can be correctly encoded and decoded out of the box, it |
439 | can be inconvenient to have to manually decode some values into a "better" |
578 | can be inconvenient to have to manually decode some values into a "better" |
… | |
… | |
579 | C<BER_TYPE_BYTES>. When you don't want that but instead prefer a hard |
718 | C<BER_TYPE_BYTES>. When you don't want that but instead prefer a hard |
580 | error for some types, then C<BER_TYPE_CROAK> is for you. |
719 | error for some types, then C<BER_TYPE_CROAK> is for you. |
581 | |
720 | |
582 | =back |
721 | =back |
583 | |
722 | |
584 | =cut |
723 | =head2 Example Profile |
585 | |
724 | |
586 | our $DEFAULT_PROFILE = new Convert::BER::XS::Profile; |
725 | The following creates a profile suitable for SNMP - it's exactly identical |
|
|
726 | to the C<$Convert::BER::XS::SNMP_PROFILE> profile. |
|
|
727 | |
587 | our $SNMP_PROFILE = new Convert::BER::XS::Profile; |
728 | our $SNMP_PROFILE = new Convert::BER::XS::Profile; |
588 | |
729 | |
589 | # additional SNMP application types |
|
|
590 | $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_IPADDRESS , BER_TYPE_IPADDRESS); |
730 | $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_IPADDRESS , BER_TYPE_IPADDRESS); |
591 | $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER32 , BER_TYPE_INT); |
731 | $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER32 , BER_TYPE_INT); |
592 | $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT); |
732 | $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT); |
593 | $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT); |
733 | $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT); |
594 | $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_IPADDRESS); |
734 | $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_IPADDRESS); |
595 | $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT); |
735 | $SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT); |
596 | |
|
|
597 | $DEFAULT_PROFILE->_set_default; |
|
|
598 | |
|
|
599 | 1; |
|
|
600 | |
736 | |
601 | =head2 LIMITATIONS/NOTES |
737 | =head2 LIMITATIONS/NOTES |
602 | |
738 | |
603 | This module can only en-/decode 64 bit signed and unsigned integers, and |
739 | This module can only en-/decode 64 bit signed and unsigned integers, and |
604 | only when your perl supports those. |
740 | only when your perl supports those. |
… | |
… | |
609 | |
745 | |
610 | OBJECT IDENTIFIEERs cannot have unlimited length, although the limit is |
746 | OBJECT IDENTIFIEERs cannot have unlimited length, although the limit is |
611 | much larger than e.g. the one imposed by SNMP or other protocols,a nd is |
747 | much larger than e.g. the one imposed by SNMP or other protocols,a nd is |
612 | about 4kB. |
748 | about 4kB. |
613 | |
749 | |
|
|
750 | Indefinite length encoding is not supported. |
|
|
751 | |
|
|
752 | Constructed strings are decoded just fine, but there should be a way to |
|
|
753 | join them for convenience. |
|
|
754 | |
614 | REAL values are not supported and will currently croak. |
755 | REAL values are not supported and will currently croak. |
|
|
756 | |
|
|
757 | The encoder and decoder tend to accept more formats than should be |
|
|
758 | strictly supported. |
615 | |
759 | |
616 | This module has undergone little to no testing so far. |
760 | This module has undergone little to no testing so far. |
617 | |
761 | |
618 | =head2 ITHREADS SUPPORT |
762 | =head2 ITHREADS SUPPORT |
619 | |
763 | |
… | |
… | |
625 | Marc Lehmann <schmorp@schmorp.de> |
769 | Marc Lehmann <schmorp@schmorp.de> |
626 | http://software.schmorp.de/pkg/Convert-BER-XS |
770 | http://software.schmorp.de/pkg/Convert-BER-XS |
627 | |
771 | |
628 | =cut |
772 | =cut |
629 | |
773 | |
|
|
774 | 1; |
|
|
775 | |