[ViewVC] Diff of: cvs/Convert-BER-XS/XS.pm

Comparing Convert-BER-XS/XS.pm (file contents):
Revision 1.3 by root, Fri Apr 19 16:49:02 2019 UTC vs.
Revision 1.24 by root, Sat Apr 20 14:59:26 2019 UTC

…		…
1	=head1 NAME	1	=head1 NAME
2		2
3	Convert::BER::XS - I<very> low level BER decoding	3	Convert::BER::XS - I<very> low level BER en-/decoding
4		4
5	=head1 SYNOPSIS	5	=head1 SYNOPSIS
6		6
7	use Convert::BER::XS ':all';	7	use Convert::BER::XS ':all';
8		8
9	my $ber = ber_decode $buf	9	my $ber = ber_decode $buf, $Convert::BER::XS::SNMP_PROFILE
10	or die "unable to decode SNMP v1/v2c Message";	10	or die "unable to decode SNMP message";
11		11
12	# the above results in a data structure consisting of (class, tag,	12	# The above results in a data structure consisting of
		13	# (class, tag, # constructed, data)
13	# constructed, data) tuples. here is such a message, SNMPv1 trap	14	# tuples. Below is such a message, SNMPv1 trap
14	# with a cisoc mac change notification	15	# with a Cisco mac change notification.
		16	# Did you know that Cisco is in the news almost
		17	# every week because of some backdoor password
		18	# or other extremely stupid security bug?
15		19
16	[ ASN_UNIVERSAL, ASN_SEQUENCE, 1,	20	[ ASN_UNIVERSAL, ASN_SEQUENCE, 1,
17	[	21	[
18	[ ASN_UNIVERSAL, ASN_INTEGER32, 0, 0 ], # snmp version 1	22	[ ASN_UNIVERSAL, ASN_INTEGER32, 0, 0 ], # snmp version 1
19	[ ASN_UNIVERSAL, 4, 0, "public" ], # community	23	[ ASN_UNIVERSAL, 4, 0, "public" ], # community
20	[ ASN_CONTEXT, 4, 1, # CHOICE, constructed	24	[ ASN_CONTEXT, 4, 1, # CHOICE, constructed - trap PDU
21	[	25	[
22	[ ASN_UNIVERSAL, ASN_OBJECT_IDENTIFIER, 0, "1.3.6.1.4.1.9.9.215.2" ], # enterprise oid	26	[ ASN_UNIVERSAL, ASN_OBJECT_IDENTIFIER, 0, "1.3.6.1.4.1.9.9.215.2" ], # enterprise oid
23	[ ASN_APPLICATION, 0, 0, "\x0a\x00\x00\x01" ], # SNMP IpAddress, 10.0.0.1	27	[ ASN_APPLICATION, SNMP_IPADDRESS, 0, "10.0.0.1" ], # SNMP IpAddress
24	[ ASN_UNIVERSAL, ASN_INTEGER32, 0, 6 ], # generic trap	28	[ ASN_UNIVERSAL, ASN_INTEGER32, 0, 6 ], # generic trap
25	[ ASN_UNIVERSAL, ASN_INTEGER32, 0, 1 ], # specific trap	29	[ ASN_UNIVERSAL, ASN_INTEGER32, 0, 1 ], # specific trap
26	[ ASN_APPLICATION, ASN_TIMETICKS, 0, 1817903850 ], # SNMP TimeTicks	30	[ ASN_APPLICATION, SNMP_TIMETICKS, 0, 1817903850 ], # SNMP TimeTicks
27	[ ASN_UNIVERSAL, ASN_SEQUENCE, 1, # the varbindlist	31	[ ASN_UNIVERSAL, ASN_SEQUENCE, 1, # the varbindlist
28	[	32	[
29	[ ASN_UNIVERSAL, ASN_SEQUENCE, 1, # a single varbind, "key value" pair	33	[ ASN_UNIVERSAL, ASN_SEQUENCE, 1, # a single varbind, "key value" pair
30	[	34	[
31	[ ASN_UNIVERSAL, ASN_OBJECT_IDENTIFIER, 0, "1.3.6.1.4.1.9.9.215.1.1.8.1.2.1" ], # the oid	35	[ ASN_UNIVERSAL, ASN_OBJECT_IDENTIFIER, 0, "1.3.6.1.4.1.9.9.215.1.1.8.1.2.1" ],
32	[ ASN_UNIVERSAL, ASN_OCTET_STRING, 0, "...data..." # the value	36	[ ASN_UNIVERSAL, ASN_OCTET_STRING, 0, "...data..." # the value
33	]	37	]
34	]	38	]
35	],	39	],
36	...	40	...
56	and (ber_is_i32 $trap->[2], 6)	60	and (ber_is_i32 $trap->[2], 6)
57	and (ber_is_i32 $trap->[3], 1) # mac changed msg	61	and (ber_is_i32 $trap->[3], 1) # mac changed msg
58	) {	62	) {
59	... and so on	63	... and so on
60		64
		65	# finally, let's encode it again and hope it results in the same bit pattern
		66
		67	my $buf = ber_encode $ber, $Convert::BER::XS::SNMP_PROFILE;
		68
61	=head1 DESCRIPTION	69	=head1 DESCRIPTION
62		70
		71	WARNING: Before release 1.0, the API is not considered stable in any way.
		72
63	This module implements a I<very> low level BER/DER decoder, and in the	73	This module implements a I<very> low level BER/DER en-/decoder.
64	future, probably also an encoder (tell me if you want an encoder, this
65	might speed up the process of getting one).
66		74
67	If is tuned for low memory and high speed, while still maintaining some	75	It is tuned for low memory and high speed, while still maintaining some
68	level of user-friendlyness.	76	level of user-friendlyness.
69		77
70	Currently, not much is documented, as this is an initial release to	78	=head2 EXPORT TAGS AND CONSTANTS
71	reserve CPAN namespace, stay tuned for a few days.	79
		80	By default this module doesn't export any symbols, but if you don't want
		81	to break your keyboard, editor or eyesight with extremely long names, I
		82	recommend importing the C<:all> tag. Still, you can selectively import
		83	things.
		84
		85	=over
		86
		87	=item C<:all>
		88
		89	All of the below. Really. Recommended for at least first steps, or if you
		90	don't care about a few kilobytes of wasted memory (and namespace).
		91
		92	=item C<:const>
		93
		94	All of the strictly ASN.1-related constants defined by this module, the
		95	same as C<:const_asn :const_index>. Notably, this does not contain
		96	C<:const_ber_type> and C<:const_snmp>.
		97
		98	A good set to get everything you need to decode and match BER data would be
		99	C<:decode :const>.
		100
		101	=item C<:const_index>
		102
		103	The BER tuple array index constants:
		104
		105	BER_CLASS BER_TAG BER_CONSTRUCTED BER_DATA
		106
		107	=item C<:const_asn>
		108
		109	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
		111	the right):
		112
		113	ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE
		114
		115	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.
		117
		118	ASN_BOOLEAN ASN_INTEGER32 ASN_BIT_STRING ASN_OCTET_STRING ASN_NULL ASN_OBJECT_IDENTIFIER
		119	ASN_OBJECT_DESCRIPTOR ASN_OID ASN_EXTERNAL ASN_REAL ASN_SEQUENCE ASN_ENUMERATED
		120	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
		122	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
		124
		125	=item C<:const_ber_type>
		126
		127	The BER type constants, explained in the PROFILES section.
		128
		129	BER_TYPE_BYTES BER_TYPE_UTF8 BER_TYPE_UCS2 BER_TYPE_UCS4 BER_TYPE_INT
		130	BER_TYPE_OID BER_TYPE_RELOID BER_TYPE_NULL BER_TYPE_BOOL BER_TYPE_REAL
		131	BER_TYPE_IPADDRESS BER_TYPE_CROAK
		132
		133	=item C<:const_snmp>
		134
		135	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
		137	BER/RFC 2578.
		138
		139	SNMP_IPADDRESS SNMP_COUNTER32 SNMP_UNSIGNED32 SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64
		140
		141	=item C<:decode>
		142
		143	C<ber_decode> and the match helper functions:
		144
		145	ber_decode ber_is ber_is_seq ber_is_i32 ber_is_oid
		146
		147	=item C<:encode>
		148
		149	C<ber_encode> and the construction helper functions:
		150
		151	ber_encode ber_i32
		152
		153	=back
		154
		155	=head2 ASN.1/BER/DER/... BASICS
		156
		157	ASN.1 is a strange language that can be used to describe protocols and
		158	data structures. It supports various mappings to JSON, XML, but most
		159	importantly, to a various binary encodings such as BER, that is the topic
		160	of this module, and is used in SNMP or LDAP for example.
		161
		162	While ASN.1 defines a schema that is useful to interpret encoded data,
		163	the BER encoding is actually somewhat self-describing: you might not know
		164	whether something is a string or a number or a sequence or something else,
		165	but you can nevertheless decode the overall structure, even if you end up
		166	with just a binary blob for the actual value.
		167
		168	This works because BER values are tagged with a type and a namespace,
		169	and also have a flag that says whether a value consists of subvalues (is
		170	"constructed") or not (is "primitive").
		171
		172	Tags are simple integers, and ASN.1 defines a somewhat weird assortment of
		173	those - for example, you have 32 bit signed integers and 16(!) different
		174	string types, but there is no Unsigned32 type for example. Different
		175	applications work around this in different ways, for example, SNMP defines
		176	application-specific Gauge32, Counter32 and Unsigned32, which are mapped
		177	to two different tags: you can distinguish between Counter32 and the
		178	others, but not between Gause32 and Unsigned32, without the ASN.1 schema.
		179
		180	Ugh.
		181
		182	=head2 DECODED BER REPRESENTATION
		183
		184	This module represents every BER value as a 4-element tuple (actually an
		185	array-reference):
		186
		187	[CLASS, TAG, CONSTRUCTED, DATA]
		188
		189	For example:
		190
		191	[ASN_UNIVERSAL, ASN_INTEGER32, 0, 177] # the integer 177
		192	[ASN_UNIVERSAL, ASN_OCTET_STRING, 0, "john"] # the string "john"
		193	[ASN_UNIVERSAL, ASN_OID, 0, "1.3.6.133"] # some OID
		194	[ASN_UNIVERSAL, ASN_SEQUENCE, 1, [ [ASN_UNIVERSAL... # a sequence
		195
		196	To avoid non-descriptive hardcoded array index numbers, this module
		197	defines symbolic constants to access these members: C<BER_CLASS>,
		198	C<BER_TAG>, C<BER_CONSTRUCTED> and C<BER_DATA>.
		199
		200	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
		202	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.:
		204
		205	$ber = ber_decode $binbuf;
		206
		207	# the following is NOT legal:
		208	$ber->[BER_CLASS] = ASN_PRIVATE; # ERROR, CLASS/TAG/CONSTRUCTED are READ ONLY(!)
		209
		210	# but all of the following are fine:
		211	$ber->[BER_DATA] = "string";
		212	$ber->[BER_DATA] = [ASN_UNIVERSAL, ASN_INTEGER32, 0, 123];
		213	@$ber = (ASN_APPLICATION, SNMP_TIMETICKS, 0, 1000);
		214
		215	I<CLASS> is something like a namespace for I<TAG>s - there is the
		216	C<ASN_UNIVERSAL> namespace which defines tags common to all ASN.1
		217	implementations, the C<ASN_APPLICATION> namespace which defines tags for
		218	specific applications (for example, the SNMP C<Unsigned32> type is in this
		219	namespace), a special-purpose context namespace (C<ASN_CONTEXT>, used e.g.
		220	for C<CHOICE>) and a private namespace (C<ASN_PRIVATE>).
		221
		222	The meaning of the I<TAG> depends on the namespace, and defines a
		223	(partial) interpretation of the data value. For example, SNMP defines
		224	extra tags in the C<ASN_APPLICATION> namespace, and to take full advantage
		225	of these, you need to tell this module how to handle those via profiles.
		226
		227	The most common tags in the C<ASN_UNIVERSAL> namespace are
		228	C<ASN_INTEGER32>, C<ASN_BIT_STRING>, C<ASN_NULL>, C<ASN_OCTET_STRING>,
		229	C<ASN_OBJECT_IDENTIFIER>, C<ASN_SEQUENCE>, C<ASN_SET> and
		230	C<ASN_IA5_STRING>.
		231
		232	The most common tags in SNMP's C<ASN_APPLICATION> namespace are
		233	C<SNMP_COUNTER32>, C<SNMP_UNSIGNED32>, C<SNMP_TIMETICKS> and
		234	C<SNMP_COUNTER64>.
		235
		236	The I<CONSTRUCTED> flag is really just a boolean - if it is false,
		237	the value is "primitive" and contains no subvalues, kind of like a
		238	non-reference perl scalar. If it is true, then the value is "constructed"
		239	which just means it contains a list of subvalues which this module will
		240	en-/decode as BER tuples themselves.
		241
		242	The I<DATA> value is either a reference to an array of further tuples (if
		243	the value is I<CONSTRUCTED>), some decoded representation of the value,
		244	if this module knows how to decode it (e.g. for the integer types above)
		245	or a binary string with the raw octets if this module doesn't know how to
		246	interpret the namespace/tag.
		247
		248	Thus, you can always decode a BER data structure and at worst you get a
		249	string in place of some nice decoded value.
		250
		251	See the SYNOPSIS for an example of such an encoded tuple representation.
		252
		253	=head2 DECODING AND ENCODING
		254
		255	=over
		256
		257	=item $tuple = ber_decoded $bindata[, $profile]
		258
		259	Decodes binary BER data in C<$bindata> and returns the resulting BER
		260	tuple. Croaks on any decoding error, so the returned C<$tuple> is always
		261	valid.
		262
		263	How tags are interpreted is defined by the second argument, which must
		264	be a C<Convert::BER::XS::Profile> object. If it is missing, the default
		265	profile will be used (C<$Convert::BER::XS::DEFAULT_PROFILE>).
		266
		267	In addition to rolling your own, this module provides a
		268	C<$Convert::BER::XS::SNMP_PROFILE> that knows about the additional SNMP
		269	types.
		270
		271	=item $bindata = ber_encode $tuple[, $profile]
		272
		273	Encodes the BER tuple into a BER/DER data structure. AS with
		274	Cyber_decode>, an optional profile can be given.
		275
		276	=back
		277
		278	=head2 HELPER FUNCTIONS
		279
		280	Working with a 4-tuple for every value can be annoying. Or, rather, I<is>
		281	annoying. To reduce this a bit, this module defines a number of helper
		282	functions, both to match BER tuples and to construct BER tuples:
		283
		284	=head3 MATCH HELPERS
		285
		286	These functions accept a BER tuple as first argument and either partially
		287	or fully match it. They often come in two forms, one which exactly matches
		288	a value, and one which only matches the type and returns the value.
		289
		290	They do check whether valid tuples are passed in and croak otherwise. As
		291	a ease-of-use exception, they usually also accept C<undef> instead of a
		292	tuple reference, in which case they silently fail to match.
		293
		294	=over
		295
		296	=item $bool = ber_is $tuple, $class, $tag, $constructed, $data
		297
		298	This takes a BER C<$tuple> and matches its elements against the provided
		299	values, all of which are optional - values that are either missing or
		300	C<undef> will be ignored, the others will be matched exactly (e.g. as if
		301	you used C<==> or C<eq> (for C<$data>)).
		302
		303	Some examples:
		304
		305	ber_is $tuple, ASN_UNIVERSAL, ASN_SEQUENCE, 1
		306	orf die "tuple is not an ASN SEQUENCE";
		307
		308	ber_is $tuple, ASN_UNIVERSAL, ASN_NULL
		309	or die "tuple is not an ASN NULL value";
		310
		311	ber_is $tuple, ASN_UNIVERSAL, ASN_INTEGER32, 0, 50
		312	or die "BER integer must be 50";
		313
		314	=item $seq = ber_is_seq $tuple
		315
		316	Returns the sequence members (the array of subvalues) if the C<$tuple> is
		317	an ASN SEQUENCE, i.e. the C<BER_DATA> member. If the C<$tuple> is not a
		318	sequence it returns C<undef>. For example, SNMP version 1/2c/3 packets all
		319	consist of an outer SEQUENCE value:
		320
		321	my $ber = ber_decode $snmp_data;
		322
		323	my $snmp = ber_is_seq $ber
		324	or die "SNMP packet invalid: does not start with SEQUENCE";
		325
		326	# now we know $snmp is a sequence, so decode the SNMP version
		327
		328	my $version = ber_is_i32 $snmp->[0]
		329	or die "SNMP packet invalid: does not start with version number";
		330
		331	=item $bool = ber_is_i32 $tuple, $i32
		332
		333	Returns a true value if the C<$tuple> represents an ASN INTEGER32 with
		334	the value C<$i32>.
		335
		336	=item $i32 = ber_is_i32 $tuple
		337
		338	Returns true (and extracts the integer value) if the C<$tuple> is an ASN
		339	INTEGER32. For C<0>, this function returns a special value that is 0 but
		340	true.
		341
		342	=item $bool = ber_is_oid $tuple, $oid_string
		343
		344	Returns true if the C<$tuple> represents an ASN_OBJECT_IDENTIFIER
		345	that exactly matches C<$oid_string>. Example:
		346
		347	ber_is_oid $tuple, "1.3.6.1.4"
		348	or die "oid must be 1.3.6.1.4";
		349
		350	=item $oid = ber_is_oid $tuple
		351
		352	Returns true (and extracts the OID string) if the C<$tuple> is an ASN
		353	OBJECT IDENTIFIER. Otherwise, it returns C<undef>.
		354
		355	=back
		356
		357	=head3 CONSTRUCTION HELPERS
		358
		359	=over
		360
		361	=item $tuple = ber_i32 $value
		362
		363	Constructs a new C<ASN_INTEGER32> tuple.
		364
		365	=back
72		366
73	=head2 RELATIONSHIP TO L<Convert::BER> and L<Convert::ASN1>	367	=head2 RELATIONSHIP TO L<Convert::BER> and L<Convert::ASN1>
74		368
75	This module is I<not> the XS version of L<Convert::BER>, but a different	369	This module is I<not> the XS version of L<Convert::BER>, but a different
76	take at doing the same thing. I imagine this module would be a good base	370	take at doing the same thing. I imagine this module would be a good base
77	for speeding up either fo these, or write a similar module, or write your	371	for speeding up either of these, or write a similar module, or write your
78	own LDAP or SNMP module for example.	372	own LDAP or SNMP module for example.
79		373
80	=cut	374	=cut
81		375
82	package Convert::BER::XS;	376	package Convert::BER::XS;
…		…
84	use common::sense;	378	use common::sense;
85		379
86	use XSLoader ();	380	use XSLoader ();
87	use Exporter qw(import);	381	use Exporter qw(import);
88		382
		383	our $VERSION;
		384
		385	BEGIN {
89	our $VERSION = '0.0';	386	$VERSION = 0.8;
90
91	XSLoader::load __PACKAGE__, $VERSION;	387	XSLoader::load __PACKAGE__, $VERSION;
		388	}
92		389
93	our %EXPORT_TAGS = (	390	our %EXPORT_TAGS = (
94	all => [qw(	391	const_index => [qw(
		392	BER_CLASS BER_TAG BER_CONSTRUCTED BER_DATA
		393	)],
		394	const_asn => [qw(
		395	ASN_BOOLEAN ASN_INTEGER32 ASN_BIT_STRING ASN_OCTET_STRING ASN_NULL ASN_OBJECT_IDENTIFIER
		396	ASN_OBJECT_DESCRIPTOR ASN_OID ASN_EXTERNAL ASN_REAL ASN_SEQUENCE ASN_ENUMERATED
		397	ASN_EMBEDDED_PDV ASN_UTF8_STRING ASN_RELATIVE_OID ASN_SET ASN_NUMERIC_STRING
		398	ASN_PRINTABLE_STRING ASN_TELETEX_STRING ASN_T61_STRING ASN_VIDEOTEX_STRING ASN_IA5_STRING
		399	ASN_ASCII_STRING ASN_UTC_TIME ASN_GENERALIZED_TIME ASN_GRAPHIC_STRING ASN_VISIBLE_STRING
		400	ASN_ISO646_STRING ASN_GENERAL_STRING ASN_UNIVERSAL_STRING ASN_CHARACTER_STRING ASN_BMP_STRING
		401
		402	ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE
		403	)],
		404	const_ber_type => [qw(
		405	BER_TYPE_BYTES BER_TYPE_UTF8 BER_TYPE_UCS2 BER_TYPE_UCS4 BER_TYPE_INT
		406	BER_TYPE_OID BER_TYPE_RELOID BER_TYPE_NULL BER_TYPE_BOOL BER_TYPE_REAL
		407	BER_TYPE_IPADDRESS BER_TYPE_CROAK
		408	)],
		409	const_snmp => [qw(
		410	SNMP_IPADDRESS SNMP_COUNTER32 SNMP_UNSIGNED32 SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64
		411	)],
		412	decode => [qw(
95	ber_decode	413	ber_decode
96	ber_is ber_is_seq ber_is_i32 ber_is_oid	414	ber_is ber_is_seq ber_is_i32 ber_is_oid
97	BER_CLASS BER_TAG BER_CONSTRUCTED BER_DATA	415	)],
98	ASN_BOOLEAN ASN_INTEGER32 ASN_BIT_STRING ASN_OCTET_STRING ASN_NULL ASN_OBJECT_IDENTIFIER ASN_TAG_BER ASN_TAG_MASK	416	encode => [qw(
99	ASN_CONSTRUCTED ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE ASN_CLASS_MASK ASN_CLASS_SHIFT	417	ber_encode
100	ASN_SEQUENCE ASN_IPADDRESS ASN_COUNTER32 ASN_UNSIGNED32 ASN_TIMETICKS ASN_OPAQUE ASN_COUNTER64	418	ber_i32
101	)],	419	)],
102	);	420	);
103		421
104	our @EXPORT_OK = map @$_, values %EXPORT_TAGS;	422	our @EXPORT_OK = map @$_, values %EXPORT_TAGS;
105		423
		424	$EXPORT_TAGS{all} = \@EXPORT_OK;
		425	$EXPORT_TAGS{const} = [map @{ $EXPORT_TAGS{$_} }, qw(const_index const_asn)];
		426	use Data::Dump; ddx \%EXPORT_TAGS;
		427
		428	=head1 PROFILES
		429
		430	While any BER data can be correctly encoded and decoded out of the box, it
		431	can be inconvenient to have to manually decode some values into a "better"
		432	format: for instance, SNMP TimeTicks values are decoded into the raw octet
		433	strings of their BER representation, which is quite hard to decode. With
		434	profiles, you can change which class/tag combinations map to which decoder
		435	function inside C<ber_decode> (and of course also which encoder functions
		436	are used in C<ber_encode>).
		437
		438	This works by mapping specific class/tag combinations to an internal "ber
		439	type".
		440
		441	The default profile supports the standard ASN.1 types, but no
		442	application-specific ones. This means that class/tag combinations not in
		443	the base set of ASN.1 are decoded into their raw octet strings.
		444
		445	C<Convert::BER::XS> defines two profile variables you can use out of the box:
		446
		447	=over
		448
		449	=item C<$Convert::BER::XS::DEFAULT_PROFILE>
		450
		451	This is the default profile, i.e. the profile that is used when no
		452	profile is specified for de-/encoding.
		453
		454	You can modify it, but remember that this modifies the defaults for all
		455	callers that rely on the default profile.
		456
		457	=item C<$Convert::BER::XS::SNMP_PROFILE>
		458
		459	A profile with mappings for SNMP-specific application tags added. This is
		460	useful when de-/encoding SNMP data.
		461
		462	Example:
		463
		464	$ber = ber_decode $data, $Convert::BER::XS::SNMP_PROFILE;
		465
		466	=back
		467
		468	=head2 The Convert::BER::XS::Profile class
		469
		470	=over
		471
		472	=item $profile = new Convert::BER::XS::Profile
		473
		474	Create a new profile. The profile will be identical to the default
		475	profile.
		476
		477	=item $profile->set ($class, $tag, $type)
		478
		479	Sets the mapping for the given C<$class>/C<$tag> combination to C<$type>,
		480	which must be one of the C<BER_TYPE_*> constants.
		481
		482	Note that currently, the mapping is stored in a flat array, so large
		483	values of C<$tag> will consume large amounts of memory.
		484
		485	Example:
		486
		487	$profile = new Convert::BER::XS::Profile;
		488	$profile->set (ASN_APPLICATION, SNMP_COUNTER32, BER_TYPE_INT);
		489	$ber = ber_decode $data, $profile;
		490
		491	=item $type = $profile->get ($class, $tag)
		492
		493	Returns the BER type mapped to the given C<$class>/C<$tag> combination.
		494
		495	=back
		496
		497	=head2 BER TYPES
		498
		499	This lists the predefined BER types - you can map any C<CLASS>/C<TAG>
		500	combination to any C<BER_TYPE_*>.
		501
		502	=over
		503
		504	=item C<BER_TYPE_BYTES>
		505
		506	The raw octets of the value. This is the default type for unknown tags and
		507	de-/encodes the value as if it were an octet string, i.e. by copying the
		508	raw bytes.
		509
		510	=item C<BER_TYPE_UTF8>
		511
		512	Like C<BER_TYPE_BYTES>, but decodes the value as if it were a UTF-8 string
		513	(without validation!) and encodes a perl unicode string into a UTF-8 BER
		514	string.
		515
		516	=item C<BER_TYPE_UCS2>
		517
		518	Similar to C<BER_TYPE_UTF8>, but treats the BER value as UCS-2 encoded
		519	string.
		520
		521	=item C<BER_TYPE_UCS4>
		522
		523	Similar to C<BER_TYPE_UTF8>, but treats the BER value as UCS-4 encoded
		524	string.
		525
		526	=item C<BER_TYPE_INT>
		527
		528	Encodes and decodes a BER integer value to a perl integer scalar. This
		529	should correctly handle 64 bit signed and unsigned values.
		530
		531	=item C<BER_TYPE_OID>
		532
		533	Encodes and decodes an OBJECT IDENTIFIER into dotted form without leading
		534	dot, e.g. C<1.3.6.1.213>.
		535
		536	=item C<BER_TYPE_RELOID>
		537
		538	Same as C<BER_TYPE_OID> but uses relative object identifier
		539	encoding: ASN.1 has this hack of encoding the first two OID components
		540	into a single integer in a weird attempt to save an insignificant amount
		541	of space in an otherwise wasteful encoding, and relative OIDs are
		542	basically OIDs without this hack. The practical difference is that the
		543	second component of an OID can only have the values 1..40, while relative
		544	OIDs do not have this restriction.
		545
		546	=item C<BER_TYPE_NULL>
		547
		548	Decodes an C<ASN_NULL> value into C<undef>, and always encodes a
		549	C<ASN_NULL> type, regardless of the perl value.
		550
		551	=item C<BER_TYPE_BOOL>
		552
		553	Decodes an C<ASN_BOOLEAN> value into C<0> or C<1>, and encodes a perl
		554	boolean value into an C<ASN_BOOLEAN>.
		555
		556	=item C<BER_TYPE_REAL>
		557
		558	Decodes/encodes a BER real value. NOT IMPLEMENTED.
		559
		560	=item C<BER_TYPE_IPADDRESS>
		561
		562	Decodes/encodes a four byte string into an IPv4 dotted-quad address string
		563	in Perl. Given the obsolete nature of this type, this is a low-effort
		564	implementation that simply uses C<sprintf> and C<sscanf>-style conversion,
		565	so it won't handle all string forms supported by C<inet_aton> for example.
		566
		567	=item C<BER_TYPE_CROAK>
		568
		569	Always croaks when encountered during encoding or decoding - the
		570	default behaviour when encountering an unknown type is to treat it as
		571	C<BER_TYPE_BYTES>. When you don't want that but instead prefer a hard
		572	error for some types, then C<BER_TYPE_CROAK> is for you.
		573
		574	=back
		575
		576	=cut
		577
		578	our $DEFAULT_PROFILE = new Convert::BER::XS::Profile;
		579	our $SNMP_PROFILE = new Convert::BER::XS::Profile;
		580
		581	# additional SNMP application types
		582	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_IPADDRESS , BER_TYPE_IPADDRESS);
		583	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER32 , BER_TYPE_INT);
		584	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT);
		585	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT);
		586	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_IPADDRESS);
		587	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT);
		588
		589	$DEFAULT_PROFILE->_set_default;
		590
106	1;	591	1;
		592
		593	=head2 LIMITATIONS/NOTES
		594
		595	This module can only en-/decode 64 bit signed and unsigned integers, and
		596	only when your perl supports those.
		597
		598	This module does not generally care about ranges, i.e. it will happily
		599	de-/encode 64 bit integers into an C<ASN_INTEGER32> value, or a negative
		600	number into an C<SNMP_COUNTER64>.
		601
		602	OBJECT IDENTIFIEERs cannot have unlimited length, although the limit is
		603	much larger than e.g. the one imposed by SNMP or other protocols,a nd is
		604	about 4kB.
		605
		606	REAL values are not supported and will currently croak.
		607
		608	This module has undergone little to no testing so far.
		609
		610	=head2 ITHREADS SUPPORT
		611
		612	This module is unlikely to work when the (officially discouraged) ithreads
		613	are in use.
107		614
108	=head1 AUTHOR	615	=head1 AUTHOR
109		616
110	Marc Lehmann <schmorp@schmorp.de>	617	Marc Lehmann <schmorp@schmorp.de>
111	http://software.schmorp.de/pkg/Convert-BER-XS	618	http://software.schmorp.de/pkg/Convert-BER-XS

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Comparing Convert-BER-XS/XS.pm (file contents): Revision 1.3 by root, Fri Apr 19 16:49:02 2019 UTC vs. Revision 1.24 by root, Sat Apr 20 14:59:26 2019 UTC

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Comparing Convert-BER-XS/XS.pm (file contents):
Revision 1.3 by root, Fri Apr 19 16:49:02 2019 UTC vs.
Revision 1.24 by root, Sat Apr 20 14:59:26 2019 UTC