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

Comparing Convert-BER-XS/XS.pm (file contents):
Revision 1.14 by root, Sat Apr 20 01:31:07 2019 UTC vs.
Revision 1.33 by root, Sat Apr 20 17:23:21 2019 UTC

…		…
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 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?
19		19
20	[ ASN_UNIVERSAL, ASN_SEQUENCE, 1,	20	[ ASN_UNIVERSAL, ASN_SEQUENCE, 1,
21	[	21	[
22	[ ASN_UNIVERSAL, ASN_INTEGER32, 0, 0 ], # snmp version 1	22	[ ASN_UNIVERSAL, ASN_INTEGER, 0, 0 ], # snmp version 1
23	[ ASN_UNIVERSAL, 4, 0, "public" ], # community	23	[ ASN_UNIVERSAL, 4, 0, "public" ], # community
24	[ ASN_CONTEXT, 4, 1, # CHOICE, constructed - trap PDU	24	[ ASN_CONTEXT, 4, 1, # CHOICE, constructed - trap PDU
25	[	25	[
26	[ 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
27	[ 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
28	[ ASN_UNIVERSAL, ASN_INTEGER32, 0, 6 ], # generic trap	28	[ ASN_UNIVERSAL, ASN_INTEGER, 0, 6 ], # generic trap
29	[ ASN_UNIVERSAL, ASN_INTEGER32, 0, 1 ], # specific trap	29	[ ASN_UNIVERSAL, ASN_INTEGER, 0, 1 ], # specific trap
30	[ ASN_APPLICATION, ASN_TIMETICKS, 0, 1817903850 ], # SNMP TimeTicks	30	[ ASN_APPLICATION, SNMP_TIMETICKS, 0, 1817903850 ], # SNMP TimeTicks
31	[ ASN_UNIVERSAL, ASN_SEQUENCE, 1, # the varbindlist	31	[ ASN_UNIVERSAL, ASN_SEQUENCE, 1, # the varbindlist
32	[	32	[
33	[ ASN_UNIVERSAL, ASN_SEQUENCE, 1, # a single varbind, "key value" pair	33	[ ASN_UNIVERSAL, ASN_SEQUENCE, 1, # a single varbind, "key value" pair
34	[	34	[
35	[ ASN_UNIVERSAL, ASN_OBJECT_IDENTIFIER, 0, "1.3.6.1.4.1.9.9.215.1.1.8.1.2.1" ],	35	[ ASN_UNIVERSAL, ASN_OBJECT_IDENTIFIER, 0, "1.3.6.1.4.1.9.9.215.1.1.8.1.2.1" ],
…		…
42	# let's decode it a bit with some helper functions	42	# let's decode it a bit with some helper functions
43		43
44	my $msg = ber_is_seq $ber	44	my $msg = ber_is_seq $ber
45	or die "SNMP message does not start with a sequence";	45	or die "SNMP message does not start with a sequence";
46		46
47	ber_is $msg->[0], ASN_UNIVERSAL, ASN_INTEGER32, 0	47	ber_is $msg->[0], ASN_UNIVERSAL, ASN_INTEGER, 0
48	or die "SNMP message does not start with snmp version\n";	48	or die "SNMP message does not start with snmp version\n";
49		49
50	# message is SNMP v1 or v2c?	50	# message is SNMP v1 or v2c?
51	if ($msg->[0][BER_DATA] == 0 \|\| $msg->[0][BER_DATA] == 1) {	51	if ($msg->[0][BER_DATA] == 0 \|\| $msg->[0][BER_DATA] == 1) {
52		52
…		…
55	my $trap = $msg->[2][BER_DATA];	55	my $trap = $msg->[2][BER_DATA];
56		56
57	# check whether trap is a cisco mac notification mac changed message	57	# check whether trap is a cisco mac notification mac changed message
58	if (	58	if (
59	(ber_is_oid $trap->[0], "1.3.6.1.4.1.9.9.215.2") # cmnInterfaceObjects	59	(ber_is_oid $trap->[0], "1.3.6.1.4.1.9.9.215.2") # cmnInterfaceObjects
60	and (ber_is_i32 $trap->[2], 6)	60	and (ber_is_int $trap->[2], 6)
61	and (ber_is_i32 $trap->[3], 1) # mac changed msg	61	and (ber_is_int $trap->[3], 1) # mac changed msg
62	) {	62	) {
63	... and so on	63	... and so on
64		64
65	# finally, let's encode it again and hope it results in the same bit pattern	65	# finally, let's encode it again and hope it results in the same bit pattern
66		66
67	my $buf = ber_encode $ber;	67	my $buf = ber_encode $ber, $Convert::BER::XS::SNMP_PROFILE;
68		68
69	=head1 DESCRIPTION	69	=head1 DESCRIPTION
70		70
71	WARNING: Before release 1.0, the API is not considered stable in any way.	71	WARNING: Before release 1.0, the API is not considered stable in any way.
72		72
73	This module implements a I<very> low level BER/DER en-/decoder.	73	This module implements a I<very> low level BER/DER en-/decoder.
74		74
75	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
76	level of user-friendlyness.	76	level of user-friendlyness.
77		77
78	Currently, not much is documented, as this is an initial release to	78	=head2 EXPORT TAGS AND CONSTANTS
79	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_FLAGS 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_INTEGER 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_GAUGE32
		140	SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64
		141
		142	=item C<:decode>
		143
		144	C<ber_decode> and the match helper functions:
		145
		146	ber_decode ber_is ber_is_seq ber_is_int ber_is_oid
		147
		148	=item C<:encode>
		149
		150	C<ber_encode> and the construction helper functions:
		151
		152	ber_encode ber_int
		153
		154	=back
80		155
81	=head2 ASN.1/BER/DER/... BASICS	156	=head2 ASN.1/BER/DER/... BASICS
82		157
83	ASN.1 is a strange language that can be sed to describe protocols and	158	ASN.1 is a strange language that can be used to describe protocols and
84	data structures. It supports various mappings to JSON, XML, but most	159	data structures. It supports various mappings to JSON, XML, but most
85	importantly, to a various binary encodings such as BER, that is the topic	160	importantly, to a various binary encodings such as BER, that is the topic
86	of this module, and is used in SNMP or LDAP for example.	161	of this module, and is used in SNMP, LDAP or X.509 for example.
87		162
88	While ASN.1 defines a schema that is useful to interpret encoded data,	163	While ASN.1 defines a schema that is useful to interpret encoded data,
89	the BER encoding is actually somewhat self-describing: you might not know	164	the BER encoding is actually somewhat self-describing: you might not know
90	whether something is a string or a number or a sequence or something else,	165	whether something is a string or a number or a sequence or something else,
91	but you can nevertheless decode the overall structure, even if you end up	166	but you can nevertheless decode the overall structure, even if you end up
92	with just a binary blob for the actual value.	167	with just a binary blob for the actual value.
93		168
94	This works because BER values are tagged with a type and a namespace,	169	This works because BER values are tagged with a type and a namespace,
95	and also have a flag that says whther a value consists of subvalues (is	170	and also have a flag that says whether a value consists of subvalues (is
96	"constructed") or not (is "primitive").	171	"constructed") or not (is "primitive").
97		172
98	Tags are simple integers, and ASN.1 defines a somewhat weird assortment of	173	Tags are simple integers, and ASN.1 defines a somewhat weird assortment
99	those - for example, you have 32 bit signed integers and 16(!) different	174	of those - for example, you have one integers and 16(!) different
100	string types, but there is no unsigned32 type for example. Different	175	string types, but there is no Unsigned32 type for example. Different
101	applications work around this in different ways, for example, SNMP defines	176	applications work around this in different ways, for example, SNMP defines
102	application-specific Gauge32, Counter32 and Unsigned32, which are mapped	177	application-specific Gauge32, Counter32 and Unsigned32, which are mapped
103	to two different tags: you can distinguish between Counter32 and the	178	to two different tags: you can distinguish between Counter32 and the
104	others, but not between Gause32 and Unsigned32, without the ASN.1 schema.	179	others, but not between Gause32 and Unsigned32, without the ASN.1 schema.
105		180
…		…
108	=head2 DECODED BER REPRESENTATION	183	=head2 DECODED BER REPRESENTATION
109		184
110	This module represents every BER value as a 4-element tuple (actually an	185	This module represents every BER value as a 4-element tuple (actually an
111	array-reference):	186	array-reference):
112		187
113	[CLASS, TAG, CONSTRUCTED, DATA]	188	[CLASS, TAG, FLAGS, DATA]
		189
		190	For example:
		191
		192	[ASN_UNIVERSAL, ASN_INTEGER, 0, 177] # the integer 177
		193	[ASN_UNIVERSAL, ASN_OCTET_STRING, 0, "john"] # the string "john"
		194	[ASN_UNIVERSAL, ASN_OID, 0, "1.3.6.133"] # some OID
		195	[ASN_UNIVERSAL, ASN_SEQUENCE, 1, [ [ASN_UNIVERSAL... # a sequence
114		196
115	To avoid non-descriptive hardcoded array index numbers, this module	197	To avoid non-descriptive hardcoded array index numbers, this module
116	defines symbolic constants to access these members: C<BER_CLASS>,	198	defines symbolic constants to access these members: C<BER_CLASS>,
117	C<BER_TAG>, C<BER_CONSTRUCTED> and C<BER_DATA>.	199	C<BER_TAG>, C<BER_FLAGS> and C<BER_DATA>.
118		200
119	Also, the first three members are integers with a little caveat: for	201	Also, the first three members are integers with a little caveat: for
120	performance reasons, these are readonly and shared, so you must not modify	202	performance reasons, these are readonly and shared, so you must not modify
121	them (increment, assign to them etc.) in any way. You may modify the	203	them (increment, assign to them etc.) in any way. You may modify the
122	I<DATA> member, and you may re-assign the array itself, e.g.:	204	I<DATA> member, and you may re-assign the array itself, e.g.:
123		205
124	$ber = ber_decode $binbuf;	206	$ber = ber_decode $binbuf;
125		207
126	# the following is NOT legal:	208	# the following is NOT legal:
127	$ber->[BER_CLASS] = ASN_PRIVATE; # ERROR, CLASS/TAG/CONSTRUCTED are READ ONLY(!)	209	$ber->[BER_CLASS] = ASN_PRIVATE; # ERROR, CLASS/TAG/FLAGS are READ ONLY(!)
128		210
129	# but all of the following are fine:	211	# but all of the following are fine:
130	$ber->[BER_DATA] = "string";	212	$ber->[BER_DATA] = "string";
131	$ber->[BER_DATA] = [ASN_UNIVERSAL, ASN_INTEGER32, 0, 123];	213	$ber->[BER_DATA] = [ASN_UNIVERSAL, ASN_INTEGER, 0, 123];
132	@$ber = (ASN_APPLICATION, SNMP_TIMETICKS, 0, 1000);	214	@$ber = (ASN_APPLICATION, SNMP_TIMETICKS, 0, 1000);
133		215
134	I<CLASS> is something like a namespace for I<TAG>s - there is the	216	I<CLASS> is something like a namespace for I<TAG>s - there is the
135	C<ASN_UNIVERSAL> namespace which defines tags common to all ASN.1	217	C<ASN_UNIVERSAL> namespace which defines tags common to all ASN.1
136	implementations, the C<ASN_APPLICATION> namespace which defines tags for	218	implementations, the C<ASN_APPLICATION> namespace which defines tags for
137	specific applications (for example, the SNMP C<Unsigned32> type is in this	219	specific applications (for example, the SNMP C<Unsigned32> type is in this
138	namespace), a special-purpose context namespace (C<ASN_CONTEXT>, used e.g.	220	namespace), a special-purpose context namespace (C<ASN_CONTEXT>, used e.g.
139	for C<CHOICE>) and a private namespace (C<ASN_PRIVATE>).	221	for C<CHOICE>) and a private namespace (C<ASN_PRIVATE>).
140		222
141	The meaning of the I<TAG> depends on the namespace, and defines a	223	The meaning of the I<TAG> depends on the namespace, and defines a
142	(partial) interpretation of the data value. For example, right now, SNMP	224	(partial) interpretation of the data value. For example, SNMP defines
143	application namespace knowledge ix hardcoded into this module, so it	225	extra tags in the C<ASN_APPLICATION> namespace, and to take full advantage
144	knows that SNMP C<Unsigned32> values need to be decoded into actual perl	226	of these, you need to tell this module how to handle those via profiles.
145	integers.
146		227
147	The most common tags in the C<ASN_UNIVERSAL> namespace are	228	The most common tags in the C<ASN_UNIVERSAL> namespace are
148	C<ASN_INTEGER32>, C<ASN_BIT_STRING>, C<ASN_NULL>, C<ASN_OCTET_STRING>,	229	C<ASN_INTEGER>, C<ASN_BIT_STRING>, C<ASN_NULL>, C<ASN_OCTET_STRING>,
149	C<ASN_OBJECT_IDENTIFIER>, C<ASN_SEQUENCE>, C<ASN_SET> and	230	C<ASN_OBJECT_IDENTIFIER>, C<ASN_SEQUENCE>, C<ASN_SET> and
150	C<ASN_IA5_STRING>.	231	C<ASN_IA5_STRING>.
151		232
152	The most common tags in SNMP's C<ASN_APPLICATION> namespace	233	The most common tags in SNMP's C<ASN_APPLICATION> namespace are
153	are C<SNMP_IPADDRESS>, C<SNMP_COUNTER32>, C<SNMP_UNSIGNED32>,	234	C<SNMP_COUNTER32>, C<SNMP_UNSIGNED32>, C<SNMP_TIMETICKS> and
154	C<SNMP_TIMETICKS>, C<SNMP_OPAQUE> and C<SNMP_COUNTER64>.	235	C<SNMP_COUNTER64>.
155		236
156	The I<CONSTRUCTED> flag is really just a boolean - if it is false, the	237	The I<FLAGS> value is really just a boolean at this time (but might
157	the value is "primitive" and contains no subvalues, kind of like a	238	get extended) - if it is C<0>, the value is "primitive" and contains
158	non-reference perl scalar. IF it is true, then the value is "constructed"	239	no subvalues, kind of like a non-reference perl scalar. If it is C<1>,
159	which just means it contains a list of subvalues which this module will	240	then the value is "constructed" which just means it contains a list of
160	en-/decode as BER tuples themselves.	241	subvalues which this module will en-/decode as BER tuples themselves.
161		242
162	The I<DATA> value is either a reference to an array of further tuples (if	243	The I<DATA> value is either a reference to an array of further tuples
163	the value is I<CONSTRUCTED>), some decoded representation of the value,	244	(if the value is I<FLAGS>), some decoded representation of the value, if
164	if this module knows how to decode it (e.g. for the integer types above)	245	this module knows how to decode it (e.g. for the integer types above) or
165	or a binary string with the raw octets if this module doesn't know how to	246	a binary string with the raw octets if this module doesn't know how to
166	interpret the namespace/tag.	247	interpret the namespace/tag.
167		248
168	Thus, you can always decode a BER data structure and at worst you get a	249	Thus, you can always decode a BER data structure and at worst you get a
169	string in place of some nice decoded value.	250	string in place of some nice decoded value.
170		251
…		…
172		253
173	=head2 DECODING AND ENCODING	254	=head2 DECODING AND ENCODING
174		255
175	=over	256	=over
176		257
177	=item $tuple = ber_decoded $bindata	258	=item $tuple = ber_decoded $bindata[, $profile]
178		259
179	Decodes binary BER data in C<$bindata> and returns the resulting BER	260	Decodes binary BER data in C<$bindata> and returns the resulting BER
180	tuple. Croaks on any decoding error, so the returned C<$tuple> is always	261	tuple. Croaks on any decoding error, so the returned C<$tuple> is always
181	valid.	262	valid.
182		263
		264	How tags are interpreted is defined by the second argument, which must
		265	be a C<Convert::BER::XS::Profile> object. If it is missing, the default
		266	profile will be used (C<$Convert::BER::XS::DEFAULT_PROFILE>).
		267
		268	In addition to rolling your own, this module provides a
		269	C<$Convert::BER::XS::SNMP_PROFILE> that knows about the additional SNMP
		270	types.
		271
		272	Example: decode a BER blob using the default profile - SNMP values will be
		273	decided as raw strings.
		274
		275	$tuple = ber_decode $data;
		276
		277	Example: as above, but use the provided SNMP profile.
		278
		279	$tuple = ber_encode $data, $Convert::BER::XS::SNMP_PROFILE;
		280
183	=item $bindata = ber_encode $tuple	281	=item $bindata = ber_encode $tuple[, $profile]
184		282
185	Encodes the BER tuple into a BER/DER data structure.	283	Encodes the BER tuple into a BER/DER data structure. AS with
		284	Cyber_decode>, an optional profile can be given.
		285
		286	The encoded data should be both BER and DER ("shortest form") compliant
		287	unless the input says otherwise (e.g. it uses constructed strings).
186		288
187	=back	289	=back
188		290
189	=head2 HELPER FUNCTIONS	291	=head2 HELPER FUNCTIONS
190		292
191	Working with a 4-tuple for every value can be annoying. Or, rather, I<is>	293	Working with a 4-tuple for every value can be annoying. Or, rather, I<is>
192	annoying. To reduce this a bit, this module defines a number of helper	294	annoying. To reduce this a bit, this module defines a number of helper
193	functions, both to match BER tuples and to conmstruct BER tuples:	295	functions, both to match BER tuples and to construct BER tuples:
194		296
195	=head3 MATCH HELPERS	297	=head3 MATCH HELPERS
196		298
197	Thse functions accept a BER tuple as first argument and either paertially	299	These functions accept a BER tuple as first argument and either partially
198	or fully match it. They often come in two forms, one which exactly matches	300	or fully match it. They often come in two forms, one which exactly matches
199	a value, and one which only matches the type and returns the value.	301	a value, and one which only matches the type and returns the value.
200		302
201	They do check whether valid tuples are passed in and croak otherwise. As	303	They do check whether valid tuples are passed in and croak otherwise. As
202	a ease-of-use exception, they usually also accept C<undef> instead of a	304	a ease-of-use exception, they usually also accept C<undef> instead of a
203	tuple reference. in which case they silently fail to match.	305	tuple reference, in which case they silently fail to match.
204		306
205	=over	307	=over
206		308
207	=item $bool = ber_is $tuple, $class, $tag, $constructed, $data	309	=item $bool = ber_is $tuple, $class, $tag, $flags, $data
208		310
209	This takes a BER C<$tuple> and matches its elements agains the privded	311	This takes a BER C<$tuple> and matches its elements against the provided
210	values, all of which are optional - values that are either missing or	312	values, all of which are optional - values that are either missing or
211	C<undef> will be ignored, the others will be matched exactly (e.g. as if	313	C<undef> will be ignored, the others will be matched exactly (e.g. as if
212	you used C<==> or C<eq> (for C<$data>)).	314	you used C<==> or C<eq> (for C<$data>)).
213		315
214	Some examples:	316	Some examples:
…		…
217	orf die "tuple is not an ASN SEQUENCE";	319	orf die "tuple is not an ASN SEQUENCE";
218		320
219	ber_is $tuple, ASN_UNIVERSAL, ASN_NULL	321	ber_is $tuple, ASN_UNIVERSAL, ASN_NULL
220	or die "tuple is not an ASN NULL value";	322	or die "tuple is not an ASN NULL value";
221		323
222	ber_is $tuple, ASN_UNIVERSAL, ASN_INTEGER32, 0, 50	324	ber_is $tuple, ASN_UNIVERSAL, ASN_INTEGER, 0, 50
223	or die "BER integer must be 50";	325	or die "BER integer must be 50";
224		326
225	=item $seq = ber_is_seq $tuple	327	=item $seq = ber_is_seq $tuple
226		328
227	Returns the sequence members (the array of subvalues) if the C<$tuple> is	329	Returns the sequence members (the array of subvalues) if the C<$tuple> is
…		…
234	my $snmp = ber_is_seq $ber	336	my $snmp = ber_is_seq $ber
235	or die "SNMP packet invalid: does not start with SEQUENCE";	337	or die "SNMP packet invalid: does not start with SEQUENCE";
236		338
237	# now we know $snmp is a sequence, so decode the SNMP version	339	# now we know $snmp is a sequence, so decode the SNMP version
238		340
239	my $version = ber_is_i32 $snmp->[0]	341	my $version = ber_is_int $snmp->[0]
240	or die "SNMP packet invalid: does not start with version number";	342	or die "SNMP packet invalid: does not start with version number";
241		343
242	=item $bool = ber_is_i32 $tuple, $i32	344	=item $bool = ber_is_int $tuple, $int
243		345
244	Returns a true value if the C<$tuple> represents an ASN INTEGER32 with	346	Returns a true value if the C<$tuple> represents an ASN INTEGER with
245	the value C<$i32>.	347	the value C<$int>.
246		348
247	=item $i32 = ber_is_i32 $tuple	349	=item $int = ber_is_int $tuple
248		350
249	Returns true (and extracts the integer value) if the C<$tuple> is an ASN	351	Returns true (and extracts the integer value) if the C<$tuple> is an
250	INTEGER32. For C<0>, this function returns a special value that is 0 but	352	C<ASN_INTEGER>. For C<0>, this function returns a special value that is 0
251	true.	353	but true.
252		354
253	=item $bool = ber_is_oid $tuple, $oid_string	355	=item $bool = ber_is_oid $tuple, $oid_string
254		356
255	Returns true if the C<$tuple> represents an ASN_OBJECT_IDENTIFIER	357	Returns true if the C<$tuple> represents an ASN_OBJECT_IDENTIFIER
256	that exactly matches C<$oid_string>. Example:	358	that exactly matches C<$oid_string>. Example:
…		…
267		369
268	=head3 CONSTRUCTION HELPERS	370	=head3 CONSTRUCTION HELPERS
269		371
270	=over	372	=over
271		373
272	=item $tuple = ber_i32 $value	374	=item $tuple = ber_int $value
273		375
274	Constructs a new C<ASN_INTEGER32> tuple.	376	Constructs a new C<ASN_INTEGER> tuple.
275		377
276	=back	378	=back
277		379
278	=head2 RELATIONSHIP TO L<Convert::BER> and L<Convert::ASN1>	380	=head2 RELATIONSHIP TO L<Convert::BER> and L<Convert::ASN1>
279		381
…		…
292	use Exporter qw(import);	394	use Exporter qw(import);
293		395
294	our $VERSION;	396	our $VERSION;
295		397
296	BEGIN {	398	BEGIN {
297	$VERSION = 0.7;	399	$VERSION = 0.9;
298	XSLoader::load __PACKAGE__, $VERSION;	400	XSLoader::load __PACKAGE__, $VERSION;
299	}	401	}
300		402
301	our %EXPORT_TAGS = (	403	our %EXPORT_TAGS = (
		404	const_index => [qw(
		405	BER_CLASS BER_TAG BER_FLAGS BER_DATA
		406	)],
302	const => [qw(	407	const_asn => [qw(
303	BER_CLASS BER_TAG BER_CONSTRUCTED BER_DATA
304
305	ASN_BOOLEAN ASN_INTEGER32 ASN_BIT_STRING ASN_OCTET_STRING ASN_NULL ASN_OBJECT_IDENTIFIER	408	ASN_BOOLEAN ASN_INTEGER ASN_BIT_STRING ASN_OCTET_STRING ASN_NULL ASN_OBJECT_IDENTIFIER
306	ASN_OBJECT_DESCRIPTOR ASN_OID ASN_EXTERNAL ASN_REAL ASN_SEQUENCE ASN_ENUMERATED	409	ASN_OBJECT_DESCRIPTOR ASN_OID ASN_EXTERNAL ASN_REAL ASN_SEQUENCE ASN_ENUMERATED
307	ASN_EMBEDDED_PDV ASN_UTF8_STRING ASN_RELATIVE_OID ASN_SET ASN_NUMERIC_STRING	410	ASN_EMBEDDED_PDV ASN_UTF8_STRING ASN_RELATIVE_OID ASN_SET ASN_NUMERIC_STRING
308	ASN_PRINTABLE_STRING ASN_TELETEX_STRING ASN_T61_STRING ASN_VIDEOTEX_STRING ASN_IA5_STRING	411	ASN_PRINTABLE_STRING ASN_TELETEX_STRING ASN_T61_STRING ASN_VIDEOTEX_STRING ASN_IA5_STRING
309	ASN_ASCII_STRING ASN_UTC_TIME ASN_GENERALIZED_TIME ASN_GRAPHIC_STRING ASN_VISIBLE_STRING	412	ASN_ASCII_STRING ASN_UTC_TIME ASN_GENERALIZED_TIME ASN_GRAPHIC_STRING ASN_VISIBLE_STRING
310	ASN_ISO646_STRING ASN_GENERAL_STRING ASN_UNIVERSAL_STRING ASN_CHARACTER_STRING ASN_BMP_STRING	413	ASN_ISO646_STRING ASN_GENERAL_STRING ASN_UNIVERSAL_STRING ASN_CHARACTER_STRING ASN_BMP_STRING
311		414
312	ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE	415	ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE
313		416	)],
		417	const_ber_type => [qw(
314	BER_TYPE_BYTES BER_TYPE_UTF8 BER_TYPE_UCS2 BER_TYPE_UCS4 BER_TYPE_INT	418	BER_TYPE_BYTES BER_TYPE_UTF8 BER_TYPE_UCS2 BER_TYPE_UCS4 BER_TYPE_INT
315	BER_TYPE_OID BER_TYPE_RELOID BER_TYPE_NULL BER_TYPE_BOOL BER_TYPE_REAL	419	BER_TYPE_OID BER_TYPE_RELOID BER_TYPE_NULL BER_TYPE_BOOL BER_TYPE_REAL
316	BER_TYPE_IPADDRESS BER_TYPE_CROAK	420	BER_TYPE_IPADDRESS BER_TYPE_CROAK
317	)],	421	)],
318	const_snmp => [qw(	422	const_snmp => [qw(
319	SNMP_IPADDRESS SNMP_COUNTER32 SNMP_UNSIGNED32 SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64	423	SNMP_IPADDRESS SNMP_COUNTER32 SNMP_GAUGE32 SNMP_UNSIGNED32
		424	SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64
		425	)],
		426	decode => [qw(
		427	ber_decode
		428	ber_is ber_is_seq ber_is_int ber_is_oid
320	)],	429	)],
321	encode => [qw(	430	encode => [qw(
322	ber_decode
323	ber_is ber_is_seq ber_is_i32 ber_is_oid
324	)],
325	decode => [qw(
326	ber_encode	431	ber_encode
327	ber_i32	432	ber_int
328	)],	433	)],
329	);	434	);
330		435
331	our @EXPORT_OK = map @$_, values %EXPORT_TAGS;	436	our @EXPORT_OK = map @$_, values %EXPORT_TAGS;
332		437
333	$EXPORT_TAGS{all} = \@EXPORT_OK;	438	$EXPORT_TAGS{all} = \@EXPORT_OK;
		439	$EXPORT_TAGS{const} = [map @{ $EXPORT_TAGS{$_} }, qw(const_index const_asn)];
334		440
335	=head1 PROFILES	441	=head1 PROFILES
336		442
337	While any BER data can be correctly encoded and decoded out of the box, it	443	While any BER data can be correctly encoded and decoded out of the box, it
338	can be inconvenient to have to manually decode some values into a "better"	444	can be inconvenient to have to manually decode some values into a "better"
…		…
347		453
348	The default profile supports the standard ASN.1 types, but no	454	The default profile supports the standard ASN.1 types, but no
349	application-specific ones. This means that class/tag combinations not in	455	application-specific ones. This means that class/tag combinations not in
350	the base set of ASN.1 are decoded into their raw octet strings.	456	the base set of ASN.1 are decoded into their raw octet strings.
351		457
352	C<Convert::BER::XS> defines two profile variables you cna use out of the box:	458	C<Convert::BER::XS> defines two profile variables you can use out of the box:
353		459
354	=over	460	=over
355		461
356	=item C<$Convert::BER::XS::DEFAULT_PROFILE>	462	=item C<$Convert::BER::XS::DEFAULT_PROFILE>
357		463
358	This is the default profile, i.e. the profile that is used when no	464	This is the default profile, i.e. the profile that is used when no
359	profile is specified for de-/encoding.	465	profile is specified for de-/encoding.
360		466
361	You cna modify it, but remember that this modifies the defaults for all	467	You can modify it, but remember that this modifies the defaults for all
362	callers that rely on the defauit profile.	468	callers that rely on the default profile.
363		469
364	=item C<$Convert::BER::XS::SNMP_PROFILE>	470	=item C<$Convert::BER::XS::SNMP_PROFILE>
365		471
366	A profile with mappings for SNMP-specific application tags added. This is	472	A profile with mappings for SNMP-specific application tags added. This is
367	useful when de-/encoding SNMP data.	473	useful when de-/encoding SNMP data.
368		474
369	Example:	475	Example:
		476
370	$ber = ber_decode $data, $Convert::BER::XS::SNMP_PROFILE;	477	$ber = ber_decode $data, $Convert::BER::XS::SNMP_PROFILE;
371		478
372	=back	479	=back
373		480
374	=head2 The Convert::BER::XS::Profile class	481	=head2 The Convert::BER::XS::Profile class
…		…
387		494
388	Note that currently, the mapping is stored in a flat array, so large	495	Note that currently, the mapping is stored in a flat array, so large
389	values of C<$tag> will consume large amounts of memory.	496	values of C<$tag> will consume large amounts of memory.
390		497
391	Example:	498	Example:
		499
392	$profile = new Convert::BER::XS::Profile;	500	$profile = new Convert::BER::XS::Profile;
393	$profile->set (ASN_APPLICATION, SNMP_COUNTER32, BER_TYPE_INT);	501	$profile->set (ASN_APPLICATION, SNMP_COUNTER32, BER_TYPE_INT);
394	$ber = ber_decode $data, $profile;	502	$ber = ber_decode $data, $profile;
395		503
396	=item $type = $profile->get ($class, $tag)	504	=item $type = $profile->get ($class, $tag)
…		…
438	Encodes and decodes an OBJECT IDENTIFIER into dotted form without leading	546	Encodes and decodes an OBJECT IDENTIFIER into dotted form without leading
439	dot, e.g. C<1.3.6.1.213>.	547	dot, e.g. C<1.3.6.1.213>.
440		548
441	=item C<BER_TYPE_RELOID>	549	=item C<BER_TYPE_RELOID>
442		550
443	Same as C<BER_TYPE_OID> but uses relative OID encoding: ASN.1 has this	551	Same as C<BER_TYPE_OID> but uses relative object identifier
444	hack of encoding the first two OID components into a single integer in a	552	encoding: ASN.1 has this hack of encoding the first two OID components
445	weird attempt to save an insignificant amount of space in an otherwise	553	into a single integer in a weird attempt to save an insignificant amount
446	wasteful encoding, and relative OIDs are basically OIDs without this	554	of space in an otherwise wasteful encoding, and relative OIDs are
447	hack. The practical difference is that the second component of an OID	555	basically OIDs without this hack. The practical difference is that the
448	can only have the values 1..40, while relative OIDs do not have this	556	second component of an OID can only have the values 1..40, while relative
449	restriction.	557	OIDs do not have this restriction.
450		558
451	=item C<BER_TYPE_NULL>	559	=item C<BER_TYPE_NULL>
452		560
453	Decodes an C<ASN_NULL> value into C<undef>, and always encodes a	561	Decodes an C<ASN_NULL> value into C<undef>, and always encodes a
454	C<ASN_NULL> type, regardless of the perl value.	562	C<ASN_NULL> type, regardless of the perl value.
…		…
462		570
463	Decodes/encodes a BER real value. NOT IMPLEMENTED.	571	Decodes/encodes a BER real value. NOT IMPLEMENTED.
464		572
465	=item C<BER_TYPE_IPADDRESS>	573	=item C<BER_TYPE_IPADDRESS>
466		574
467	Decodes/encodes a four byte string into an IOv4 dotted-quad address string	575	Decodes/encodes a four byte string into an IPv4 dotted-quad address string
468	in perl. Given ther obsolete nature of this type, this is a low-effort	576	in Perl. Given the obsolete nature of this type, this is a low-effort
469	implementation that simply uses C<sprintf> and C<sscanf>-style conversion,	577	implementation that simply uses C<sprintf> and C<sscanf>-style conversion,
470	so it won't handle all string forms supported by C<inet_aton>.	578	so it won't handle all string forms supported by C<inet_aton> for example.
471		579
472	=item C<BER_TYPE_CROAK>	580	=item C<BER_TYPE_CROAK>
473		581
474	Always croaks when encountered during encoding or decoding - the	582	Always croaks when encountered during encoding or decoding - the
475	default behaviour when encountering an unknown type is to treat it as	583	default behaviour when encountering an unknown type is to treat it as
476	C<BER_TYPE_BYTES>. When you don't want that but instead prefer a hard	584	C<BER_TYPE_BYTES>. When you don't want that but instead prefer a hard
477	error for some types, then CyBER_TYPE_CROAK> is for you.	585	error for some types, then C<BER_TYPE_CROAK> is for you.
478		586
479	=back	587	=back
480		588
		589	=head2 Example Profile
		590
		591	The following creates a profile suitable for SNMP - it's exactly identical
		592	to the C<$Convert::BER::XS::SNMP_PROFILE> profile.
		593
		594	our $SNMP_PROFILE = new Convert::BER::XS::Profile;
		595
		596	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_IPADDRESS , BER_TYPE_IPADDRESS);
		597	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER32 , BER_TYPE_INT);
		598	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT);
		599	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT);
		600	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_IPADDRESS);
		601	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT);
		602
481	=cut	603	=cut
482		604
483	our $DEFAULT_PROFILE = new Convert::BER::XS::Profile;	605	our $DEFAULT_PROFILE = new Convert::BER::XS::Profile;
		606
		607	$DEFAULT_PROFILE->_set_default;
		608
		609	# additional SNMP application types
484	our $SNMP_PROFILE = new Convert::BER::XS::Profile;	610	our $SNMP_PROFILE = new Convert::BER::XS::Profile;
485		611
486	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_IPADDRESS , BER_TYPE_IPADDRESS);	612	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_IPADDRESS , BER_TYPE_IPADDRESS);
487	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER32 , BER_TYPE_INT);	613	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER32 , BER_TYPE_INT);
488	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT);	614	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT);
489	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT);	615	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT);
490	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_IPADDRESS);	616	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_IPADDRESS);
491	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT);	617	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT);
492		618
493	$DEFAULT_PROFILE->_set_default;
494
495	1;	619	1;
496		620
497	=head2 LIMITATIONS	621	=head2 LIMITATIONS/NOTES
498		622
499	This module can only en-/decode 64 bit signed and unsigned integers, and	623	This module can only en-/decode 64 bit signed and unsigned integers, and
500	only when your perl supports those.	624	only when your perl supports those.
501		625
		626	This module does not generally care about ranges, i.e. it will happily
		627	de-/encode 64 bit integers into an C<ASN_INTEGER> value, or a negative
		628	number into an C<SNMP_COUNTER64>.
		629
502	OBJECT IDENTIFIEERS cannot have unlimited length, although the limit is	630	OBJECT IDENTIFIEERs cannot have unlimited length, although the limit is
503	much larger than e.g. the one imposed by SNMP or other protocols.	631	much larger than e.g. the one imposed by SNMP or other protocols,a nd is
		632	about 4kB.
504		633
		634	Indefinite length encoding is not supported.
		635
		636	Constructed strings are decoded just fine, but there should be a way to
		637	join them for convenience.
		638
505	REAL values are not supported and will croak.	639	REAL values are not supported and will currently croak.
		640
		641	The encoder and decoder tend to accept more formats than should be
		642	strictly supported.
506		643
507	This module has undergone little to no testing so far.	644	This module has undergone little to no testing so far.
		645
		646	=head2 ITHREADS SUPPORT
		647
		648	This module is unlikely to work when the (officially discouraged) ithreads
		649	are in use.
508		650
509	=head1 AUTHOR	651	=head1 AUTHOR
510		652
511	Marc Lehmann <schmorp@schmorp.de>	653	Marc Lehmann <schmorp@schmorp.de>
512	http://software.schmorp.de/pkg/Convert-BER-XS	654	http://software.schmorp.de/pkg/Convert-BER-XS

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Comparing Convert-BER-XS/XS.pm (file contents): Revision 1.14 by root, Sat Apr 20 01:31:07 2019 UTC vs. Revision 1.33 by root, Sat Apr 20 17:23:21 2019 UTC

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Comparing Convert-BER-XS/XS.pm (file contents):
Revision 1.14 by root, Sat Apr 20 01:31:07 2019 UTC vs.
Revision 1.33 by root, Sat Apr 20 17:23:21 2019 UTC