[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 1.35 by root, Sat Apr 20 21:51:40 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-decode_prefix
		147	ber_is ber_is_seq ber_is_int ber_is_oid
		148
		149	=item C<:encode>
		150
		151	C<ber_encode> and the construction helper functions:
		152
		153	ber_encode
		154	ber_int
		155
		156	=back
80		157
81	=head2 ASN.1/BER/DER/... BASICS	158	=head2 ASN.1/BER/DER/... BASICS
82		159
83	ASN.1 is a strange language that can be sed to describe protocols and	160	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	161	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	162	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.	163	of this module, and is used in SNMP, LDAP or X.509 for example.
87		164
88	While ASN.1 defines a schema that is useful to interpret encoded data,	165	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	166	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,	167	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	168	but you can nevertheless decode the overall structure, even if you end up
92	with just a binary blob for the actual value.	169	with just a binary blob for the actual value.
93		170
94	This works because BER values are tagged with a type and a namespace,	171	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	172	and also have a flag that says whether a value consists of subvalues (is
96	"constructed") or not (is "primitive").	173	"constructed") or not (is "primitive").
97		174
98	Tags are simple integers, and ASN.1 defines a somewhat weird assortment of	175	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	176	of those - for example, you have one integers and 16(!) different
100	string types, but there is no unsigned32 type for example. Different	177	string types, but there is no Unsigned32 type for example. Different
101	applications work around this in different ways, for example, SNMP defines	178	applications work around this in different ways, for example, SNMP defines
102	application-specific Gauge32, Counter32 and Unsigned32, which are mapped	179	application-specific Gauge32, Counter32 and Unsigned32, which are mapped
103	to two different tags: you can distinguish between Counter32 and the	180	to two different tags: you can distinguish between Counter32 and the
104	others, but not between Gause32 and Unsigned32, without the ASN.1 schema.	181	others, but not between Gause32 and Unsigned32, without the ASN.1 schema.
105		182
…		…
108	=head2 DECODED BER REPRESENTATION	185	=head2 DECODED BER REPRESENTATION
109		186
110	This module represents every BER value as a 4-element tuple (actually an	187	This module represents every BER value as a 4-element tuple (actually an
111	array-reference):	188	array-reference):
112		189
113	[CLASS, TAG, CONSTRUCTED, DATA]	190	[CLASS, TAG, FLAGS, DATA]
		191
		192	For example:
		193
		194	[ASN_UNIVERSAL, ASN_INTEGER, 0, 177] # the integer 177
		195	[ASN_UNIVERSAL, ASN_OCTET_STRING, 0, "john"] # the string "john"
		196	[ASN_UNIVERSAL, ASN_OID, 0, "1.3.6.133"] # some OID
		197	[ASN_UNIVERSAL, ASN_SEQUENCE, 1, [ [ASN_UNIVERSAL... # a sequence
114		198
115	To avoid non-descriptive hardcoded array index numbers, this module	199	To avoid non-descriptive hardcoded array index numbers, this module
116	defines symbolic constants to access these members: C<BER_CLASS>,	200	defines symbolic constants to access these members: C<BER_CLASS>,
117	C<BER_TAG>, C<BER_CONSTRUCTED> and C<BER_DATA>.	201	C<BER_TAG>, C<BER_FLAGS> and C<BER_DATA>.
118		202
119	Also, the first three members are integers with a little caveat: for	203	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	204	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	205	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.:	206	I<DATA> member, and you may re-assign the array itself, e.g.:
123		207
124	$ber = ber_decode $binbuf;	208	$ber = ber_decode $binbuf;
125		209
126	# the following is NOT legal:	210	# the following is NOT legal:
127	$ber->[BER_CLASS] = ASN_PRIVATE; # ERROR, CLASS/TAG/CONSTRUCTED are READ ONLY(!)	211	$ber->[BER_CLASS] = ASN_PRIVATE; # ERROR, CLASS/TAG/FLAGS are READ ONLY(!)
128		212
129	# but all of the following are fine:	213	# but all of the following are fine:
130	$ber->[BER_DATA] = "string";	214	$ber->[BER_DATA] = "string";
131	$ber->[BER_DATA] = [ASN_UNIVERSAL, ASN_INTEGER32, 0, 123];	215	$ber->[BER_DATA] = [ASN_UNIVERSAL, ASN_INTEGER, 0, 123];
132	@$ber = (ASN_APPLICATION, SNMP_TIMETICKS, 0, 1000);	216	@$ber = (ASN_APPLICATION, SNMP_TIMETICKS, 0, 1000);
133		217
134	I<CLASS> is something like a namespace for I<TAG>s - there is the	218	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	219	C<ASN_UNIVERSAL> namespace which defines tags common to all ASN.1
136	implementations, the C<ASN_APPLICATION> namespace which defines tags for	220	implementations, the C<ASN_APPLICATION> namespace which defines tags for
137	specific applications (for example, the SNMP C<Unsigned32> type is in this	221	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.	222	namespace), a special-purpose context namespace (C<ASN_CONTEXT>, used e.g.
139	for C<CHOICE>) and a private namespace (C<ASN_PRIVATE>).	223	for C<CHOICE>) and a private namespace (C<ASN_PRIVATE>).
140		224
141	The meaning of the I<TAG> depends on the namespace, and defines a	225	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	226	(partial) interpretation of the data value. For example, SNMP defines
143	application namespace knowledge ix hardcoded into this module, so it	227	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	228	of these, you need to tell this module how to handle those via profiles.
145	integers.
146		229
147	The most common tags in the C<ASN_UNIVERSAL> namespace are	230	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>,	231	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	232	C<ASN_OBJECT_IDENTIFIER>, C<ASN_SEQUENCE>, C<ASN_SET> and
150	C<ASN_IA5_STRING>.	233	C<ASN_IA5_STRING>.
151		234
152	The most common tags in SNMP's C<ASN_APPLICATION> namespace	235	The most common tags in SNMP's C<ASN_APPLICATION> namespace are
153	are C<SNMP_IPADDRESS>, C<SNMP_COUNTER32>, C<SNMP_UNSIGNED32>,	236	C<SNMP_COUNTER32>, C<SNMP_UNSIGNED32>, C<SNMP_TIMETICKS> and
154	C<SNMP_TIMETICKS>, C<SNMP_OPAQUE> and C<SNMP_COUNTER64>.	237	C<SNMP_COUNTER64>.
155		238
156	The I<CONSTRUCTED> flag is really just a boolean - if it is false, the	239	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	240	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"	241	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	242	then the value is "constructed" which just means it contains a list of
160	en-/decode as BER tuples themselves.	243	subvalues which this module will en-/decode as BER tuples themselves.
161		244
162	The I<DATA> value is either a reference to an array of further tuples (if	245	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,	246	(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)	247	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	248	a binary string with the raw octets if this module doesn't know how to
166	interpret the namespace/tag.	249	interpret the namespace/tag.
167		250
168	Thus, you can always decode a BER data structure and at worst you get a	251	Thus, you can always decode a BER data structure and at worst you get a
169	string in place of some nice decoded value.	252	string in place of some nice decoded value.
170		253
…		…
172		255
173	=head2 DECODING AND ENCODING	256	=head2 DECODING AND ENCODING
174		257
175	=over	258	=over
176		259
177	=item $tuple = ber_decoded $bindata	260	=item $tuple = ber_decode $bindata[, $profile]
178		261
179	Decodes binary BER data in C<$bindata> and returns the resulting BER	262	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	263	tuple. Croaks on any decoding error, so the returned C<$tuple> is always
181	valid.	264	valid.
182		265
		266	How tags are interpreted is defined by the second argument, which must
		267	be a C<Convert::BER::XS::Profile> object. If it is missing, the default
		268	profile will be used (C<$Convert::BER::XS::DEFAULT_PROFILE>).
		269
		270	In addition to rolling your own, this module provides a
		271	C<$Convert::BER::XS::SNMP_PROFILE> that knows about the additional SNMP
		272	types.
		273
		274	Example: decode a BER blob using the default profile - SNMP values will be
		275	decided as raw strings.
		276
		277	$tuple = ber_decode $data;
		278
		279	Example: as above, but use the provided SNMP profile.
		280
		281	$tuple = ber_encode $data, $Convert::BER::XS::SNMP_PROFILE;
		282
		283	=item ($tuple, $bytes) = ber_decode_prefix $bindata[, $profile]
		284
		285	Works like C<ber_decode>, except it doesn't croak when there is data after
		286	the BER data, but instead returns the decoded value and the number of
		287	bytes it decoded.
		288
		289	This is useful when you have BER data at the start of a buffer and other
		290	data after, and you need to find the length.
		291
		292	Also, since BER is self-delimited, this can be used to decode multiple BER
		293	values joined together.
		294
183	=item $bindata = ber_encode $tuple	295	=item $bindata = ber_encode $tuple[, $profile]
184		296
185	Encodes the BER tuple into a BER/DER data structure.	297	Encodes the BER tuple into a BER/DER data structure. AS with
		298	Cyber_decode>, an optional profile can be given.
		299
		300	The encoded data should be both BER and DER ("shortest form") compliant
		301	unless the input says otherwise (e.g. it uses constructed strings).
186		302
187	=back	303	=back
188		304
189	=head2 HELPER FUNCTIONS	305	=head2 HELPER FUNCTIONS
190		306
191	Working with a 4-tuple for every value can be annoying. Or, rather, I<is>	307	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	308	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:	309	functions, both to match BER tuples and to construct BER tuples:
194		310
195	=head3 MATCH HELPERS	311	=head3 MATCH HELPERS
196		312
197	Thse functions accept a BER tuple as first argument and either paertially	313	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	314	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.	315	a value, and one which only matches the type and returns the value.
200		316
201	They do check whether valid tuples are passed in and croak otherwise. As	317	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	318	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.	319	tuple reference, in which case they silently fail to match.
204		320
205	=over	321	=over
206		322
207	=item $bool = ber_is $tuple, $class, $tag, $constructed, $data	323	=item $bool = ber_is $tuple, $class, $tag, $flags, $data
208		324
209	This takes a BER C<$tuple> and matches its elements agains the privded	325	This takes a BER C<$tuple> and matches its elements against the provided
210	values, all of which are optional - values that are either missing or	326	values, all of which are optional - values that are either missing or
211	C<undef> will be ignored, the others will be matched exactly (e.g. as if	327	C<undef> will be ignored, the others will be matched exactly (e.g. as if
212	you used C<==> or C<eq> (for C<$data>)).	328	you used C<==> or C<eq> (for C<$data>)).
213		329
214	Some examples:	330	Some examples:
…		…
217	orf die "tuple is not an ASN SEQUENCE";	333	orf die "tuple is not an ASN SEQUENCE";
218		334
219	ber_is $tuple, ASN_UNIVERSAL, ASN_NULL	335	ber_is $tuple, ASN_UNIVERSAL, ASN_NULL
220	or die "tuple is not an ASN NULL value";	336	or die "tuple is not an ASN NULL value";
221		337
222	ber_is $tuple, ASN_UNIVERSAL, ASN_INTEGER32, 0, 50	338	ber_is $tuple, ASN_UNIVERSAL, ASN_INTEGER, 0, 50
223	or die "BER integer must be 50";	339	or die "BER integer must be 50";
224		340
225	=item $seq = ber_is_seq $tuple	341	=item $seq = ber_is_seq $tuple
226		342
227	Returns the sequence members (the array of subvalues) if the C<$tuple> is	343	Returns the sequence members (the array of subvalues) if the C<$tuple> is
…		…
234	my $snmp = ber_is_seq $ber	350	my $snmp = ber_is_seq $ber
235	or die "SNMP packet invalid: does not start with SEQUENCE";	351	or die "SNMP packet invalid: does not start with SEQUENCE";
236		352
237	# now we know $snmp is a sequence, so decode the SNMP version	353	# now we know $snmp is a sequence, so decode the SNMP version
238		354
239	my $version = ber_is_i32 $snmp->[0]	355	my $version = ber_is_int $snmp->[0]
240	or die "SNMP packet invalid: does not start with version number";	356	or die "SNMP packet invalid: does not start with version number";
241		357
242	=item $bool = ber_is_i32 $tuple, $i32	358	=item $bool = ber_is_int $tuple, $int
243		359
244	Returns a true value if the C<$tuple> represents an ASN INTEGER32 with	360	Returns a true value if the C<$tuple> represents an ASN INTEGER with
245	the value C<$i32>.	361	the value C<$int>.
246		362
247	=item $i32 = ber_is_i32 $tuple	363	=item $int = ber_is_int $tuple
248		364
249	Returns true (and extracts the integer value) if the C<$tuple> is an ASN	365	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	366	C<ASN_INTEGER>. For C<0>, this function returns a special value that is 0
251	true.	367	but true.
252		368
253	=item $bool = ber_is_oid $tuple, $oid_string	369	=item $bool = ber_is_oid $tuple, $oid_string
254		370
255	Returns true if the C<$tuple> represents an ASN_OBJECT_IDENTIFIER	371	Returns true if the C<$tuple> represents an ASN_OBJECT_IDENTIFIER
256	that exactly matches C<$oid_string>. Example:	372	that exactly matches C<$oid_string>. Example:
…		…
267		383
268	=head3 CONSTRUCTION HELPERS	384	=head3 CONSTRUCTION HELPERS
269		385
270	=over	386	=over
271		387
272	=item $tuple = ber_i32 $value	388	=item $tuple = ber_int $value
273		389
274	Constructs a new C<ASN_INTEGER32> tuple.	390	Constructs a new C<ASN_INTEGER> tuple.
275		391
276	=back	392	=back
277		393
278	=head2 RELATIONSHIP TO L<Convert::BER> and L<Convert::ASN1>	394	=head2 RELATIONSHIP TO L<Convert::BER> and L<Convert::ASN1>
279		395
…		…
292	use Exporter qw(import);	408	use Exporter qw(import);
293		409
294	our $VERSION;	410	our $VERSION;
295		411
296	BEGIN {	412	BEGIN {
297	$VERSION = 0.7;	413	$VERSION = '1.0';
298	XSLoader::load __PACKAGE__, $VERSION;	414	XSLoader::load __PACKAGE__, $VERSION;
299	}	415	}
300		416
301	our %EXPORT_TAGS = (	417	our %EXPORT_TAGS = (
		418	const_index => [qw(
		419	BER_CLASS BER_TAG BER_FLAGS BER_DATA
		420	)],
302	const => [qw(	421	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	422	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	423	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	424	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	425	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	426	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	427	ASN_ISO646_STRING ASN_GENERAL_STRING ASN_UNIVERSAL_STRING ASN_CHARACTER_STRING ASN_BMP_STRING
311		428
312	ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE	429	ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE
313		430	)],
		431	const_ber_type => [qw(
314	BER_TYPE_BYTES BER_TYPE_UTF8 BER_TYPE_UCS2 BER_TYPE_UCS4 BER_TYPE_INT	432	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	433	BER_TYPE_OID BER_TYPE_RELOID BER_TYPE_NULL BER_TYPE_BOOL BER_TYPE_REAL
316	BER_TYPE_IPADDRESS BER_TYPE_CROAK	434	BER_TYPE_IPADDRESS BER_TYPE_CROAK
317	)],	435	)],
318	const_snmp => [qw(	436	const_snmp => [qw(
319	SNMP_IPADDRESS SNMP_COUNTER32 SNMP_UNSIGNED32 SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64	437	SNMP_IPADDRESS SNMP_COUNTER32 SNMP_GAUGE32 SNMP_UNSIGNED32
		438	SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64
		439	)],
		440	decode => [qw(
		441	ber_decode ber_decode_prefix
		442	ber_is ber_is_seq ber_is_int ber_is_oid
320	)],	443	)],
321	encode => [qw(	444	encode => [qw(
322	ber_decode
323	ber_is ber_is_seq ber_is_i32 ber_is_oid
324	)],
325	decode => [qw(
326	ber_encode	445	ber_encode
327	ber_i32	446	ber_int
328	)],	447	)],
329	);	448	);
330		449
331	our @EXPORT_OK = map @$_, values %EXPORT_TAGS;	450	our @EXPORT_OK = map @$_, values %EXPORT_TAGS;
332		451
333	$EXPORT_TAGS{all} = \@EXPORT_OK;	452	$EXPORT_TAGS{all} = \@EXPORT_OK;
		453	$EXPORT_TAGS{const} = [map @{ $EXPORT_TAGS{$_} }, qw(const_index const_asn)];
334		454
335	=head1 PROFILES	455	=head1 PROFILES
336		456
337	While any BER data can be correctly encoded and decoded out of the box, it	457	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"	458	can be inconvenient to have to manually decode some values into a "better"
…		…
347		467
348	The default profile supports the standard ASN.1 types, but no	468	The default profile supports the standard ASN.1 types, but no
349	application-specific ones. This means that class/tag combinations not in	469	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.	470	the base set of ASN.1 are decoded into their raw octet strings.
351		471
352	C<Convert::BER::XS> defines two profile variables you cna use out of the box:	472	C<Convert::BER::XS> defines two profile variables you can use out of the box:
353		473
354	=over	474	=over
355		475
356	=item C<$Convert::BER::XS::DEFAULT_PROFILE>	476	=item C<$Convert::BER::XS::DEFAULT_PROFILE>
357		477
358	This is the default profile, i.e. the profile that is used when no	478	This is the default profile, i.e. the profile that is used when no
359	profile is specified for de-/encoding.	479	profile is specified for de-/encoding.
360		480
361	You cna modify it, but remember that this modifies the defaults for all	481	You can modify it, but remember that this modifies the defaults for all
362	callers that rely on the defauit profile.	482	callers that rely on the default profile.
363		483
364	=item C<$Convert::BER::XS::SNMP_PROFILE>	484	=item C<$Convert::BER::XS::SNMP_PROFILE>
365		485
366	A profile with mappings for SNMP-specific application tags added. This is	486	A profile with mappings for SNMP-specific application tags added. This is
367	useful when de-/encoding SNMP data.	487	useful when de-/encoding SNMP data.
368		488
369	Example:	489	Example:
		490
370	$ber = ber_decode $data, $Convert::BER::XS::SNMP_PROFILE;	491	$ber = ber_decode $data, $Convert::BER::XS::SNMP_PROFILE;
371		492
372	=back	493	=back
373		494
374	=head2 The Convert::BER::XS::Profile class	495	=head2 The Convert::BER::XS::Profile class
…		…
387		508
388	Note that currently, the mapping is stored in a flat array, so large	509	Note that currently, the mapping is stored in a flat array, so large
389	values of C<$tag> will consume large amounts of memory.	510	values of C<$tag> will consume large amounts of memory.
390		511
391	Example:	512	Example:
		513
392	$profile = new Convert::BER::XS::Profile;	514	$profile = new Convert::BER::XS::Profile;
393	$profile->set (ASN_APPLICATION, SNMP_COUNTER32, BER_TYPE_INT);	515	$profile->set (ASN_APPLICATION, SNMP_COUNTER32, BER_TYPE_INT);
394	$ber = ber_decode $data, $profile;	516	$ber = ber_decode $data, $profile;
395		517
396	=item $type = $profile->get ($class, $tag)	518	=item $type = $profile->get ($class, $tag)
…		…
438	Encodes and decodes an OBJECT IDENTIFIER into dotted form without leading	560	Encodes and decodes an OBJECT IDENTIFIER into dotted form without leading
439	dot, e.g. C<1.3.6.1.213>.	561	dot, e.g. C<1.3.6.1.213>.
440		562
441	=item C<BER_TYPE_RELOID>	563	=item C<BER_TYPE_RELOID>
442		564
443	Same as C<BER_TYPE_OID> but uses relative OID encoding: ASN.1 has this	565	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	566	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	567	into a single integer in a weird attempt to save an insignificant amount
446	wasteful encoding, and relative OIDs are basically OIDs without this	568	of space in an otherwise wasteful encoding, and relative OIDs are
447	hack. The practical difference is that the second component of an OID	569	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	570	second component of an OID can only have the values 1..40, while relative
449	restriction.	571	OIDs do not have this restriction.
450		572
451	=item C<BER_TYPE_NULL>	573	=item C<BER_TYPE_NULL>
452		574
453	Decodes an C<ASN_NULL> value into C<undef>, and always encodes a	575	Decodes an C<ASN_NULL> value into C<undef>, and always encodes a
454	C<ASN_NULL> type, regardless of the perl value.	576	C<ASN_NULL> type, regardless of the perl value.
…		…
462		584
463	Decodes/encodes a BER real value. NOT IMPLEMENTED.	585	Decodes/encodes a BER real value. NOT IMPLEMENTED.
464		586
465	=item C<BER_TYPE_IPADDRESS>	587	=item C<BER_TYPE_IPADDRESS>
466		588
467	Decodes/encodes a four byte string into an IOv4 dotted-quad address string	589	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	590	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,	591	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>.	592	so it won't handle all string forms supported by C<inet_aton> for example.
471		593
472	=item C<BER_TYPE_CROAK>	594	=item C<BER_TYPE_CROAK>
473		595
474	Always croaks when encountered during encoding or decoding - the	596	Always croaks when encountered during encoding or decoding - the
475	default behaviour when encountering an unknown type is to treat it as	597	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	598	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.	599	error for some types, then C<BER_TYPE_CROAK> is for you.
478		600
479	=back	601	=back
480		602
		603	=head2 Example Profile
		604
		605	The following creates a profile suitable for SNMP - it's exactly identical
		606	to the C<$Convert::BER::XS::SNMP_PROFILE> profile.
		607
		608	our $SNMP_PROFILE = new Convert::BER::XS::Profile;
		609
		610	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_IPADDRESS , BER_TYPE_IPADDRESS);
		611	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER32 , BER_TYPE_INT);
		612	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT);
		613	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT);
		614	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_IPADDRESS);
		615	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT);
		616
481	=cut	617	=cut
482		618
483	our $DEFAULT_PROFILE = new Convert::BER::XS::Profile;	619	our $DEFAULT_PROFILE = new Convert::BER::XS::Profile;
		620
		621	$DEFAULT_PROFILE->_set_default;
		622
		623	# additional SNMP application types
484	our $SNMP_PROFILE = new Convert::BER::XS::Profile;	624	our $SNMP_PROFILE = new Convert::BER::XS::Profile;
485		625
486	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_IPADDRESS , BER_TYPE_IPADDRESS);	626	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_IPADDRESS , BER_TYPE_IPADDRESS);
487	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER32 , BER_TYPE_INT);	627	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER32 , BER_TYPE_INT);
488	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT);	628	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT);
489	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT);	629	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT);
490	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_IPADDRESS);	630	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_IPADDRESS);
491	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT);	631	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT);
492		632
493	$DEFAULT_PROFILE->_set_default;
494
495	1;	633	1;
496		634
497	=head2 LIMITATIONS	635	=head2 LIMITATIONS/NOTES
498		636
499	This module can only en-/decode 64 bit signed and unsigned integers, and	637	This module can only en-/decode 64 bit signed and unsigned integers, and
500	only when your perl supports those.	638	only when your perl supports those.
501		639
		640	This module does not generally care about ranges, i.e. it will happily
		641	de-/encode 64 bit integers into an C<ASN_INTEGER> value, or a negative
		642	number into an C<SNMP_COUNTER64>.
		643
502	OBJECT IDENTIFIEERS cannot have unlimited length, although the limit is	644	OBJECT IDENTIFIEERs cannot have unlimited length, although the limit is
503	much larger than e.g. the one imposed by SNMP or other protocols.	645	much larger than e.g. the one imposed by SNMP or other protocols,a nd is
		646	about 4kB.
504		647
		648	Indefinite length encoding is not supported.
		649
		650	Constructed strings are decoded just fine, but there should be a way to
		651	join them for convenience.
		652
505	REAL values are not supported and will croak.	653	REAL values are not supported and will currently croak.
		654
		655	The encoder and decoder tend to accept more formats than should be
		656	strictly supported.
506		657
507	This module has undergone little to no testing so far.	658	This module has undergone little to no testing so far.
		659
		660	=head2 ITHREADS SUPPORT
		661
		662	This module is unlikely to work when the (officially discouraged) ithreads
		663	are in use.
508		664
509	=head1 AUTHOR	665	=head1 AUTHOR
510		666
511	Marc Lehmann <schmorp@schmorp.de>	667	Marc Lehmann <schmorp@schmorp.de>
512	http://software.schmorp.de/pkg/Convert-BER-XS	668	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 1.35 by root, Sat Apr 20 21:51:40 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 1.35 by root, Sat Apr 20 21:51:40 2019 UTC