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

Comparing Convert-BER-XS/XS.pm (file contents):
Revision 1.19 by root, Sat Apr 20 14:45:03 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	=head2 EXPORT TAGS AND CONSTANTS	78	=head2 EXPORT TAGS AND CONSTANTS
79		79
80	By default this module doesn't export any symbols, but if you don't want	80	By default this module doesn't export any symbols, but if you don't want
81	to break your keyboard, editor or eyesigh with extreemly long names, I	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	82	recommend importing the C<:all> tag. Still, you can selectively import
83	things:	83	things.
84		84
85	=over	85	=over
86		86
87	=item :all	87	=item C<:all>
88		88
89	All of the below. Really. Rcommended for at least first steps, or if you	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).	90	don't care about a few kilobytes of wasted memory (and namespace).
91		91
92	=item :const	92	=item C<:const>
93		93
94	All of the stricly ASN.1-related constants defined by this module, the	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	95	same as C<:const_asn :const_index>. Notably, this does not contain
96	C<:const_ber_type> and C<:const_snmp>.	96	C<:const_ber_type> and C<:const_snmp>.
97		97
98	A good set to get everything you need to decode and match BER data would be	98	A good set to get everything you need to decode and match BER data would be
99	C<:decode :const>.	99	C<:decode :const>.
100		100
101	=item C<:const_index>>	101	=item C<:const_index>
102		102
103	The BER tuple array index constants:	103	The BER tuple array index constants:
104		104
105	BER_CLASS BER_TAG BER_CONSTRUCTED BER_DATA	105	BER_CLASS BER_TAG BER_FLAGS BER_DATA
106		106
107	=item C<:const_asn>	107	=item C<:const_asn>
108		108
109	ASN class values (these are C<0>, C<1>, C<2> and C<3>, reespectively -	109	ASN class values (these are C<0>, C<1>, C<2> and C<3>, respectively -
110	exactly thw two topmost bits from the identifdier octet shifted 6 bits to	110	exactly thw two topmost bits from the identifier octet shifted 6 bits to
111	the right):	111	the right):
112		112
113	ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE	113	ASN_UNIVERSAL ASN_APPLICATION ASN_CONTEXT ASN_PRIVATE
114		114
115	ASN tag values (some of which are aliases, such as C<ASN_OID>). Their	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.	116	numerical value corresponds exactly to the numbers used in BER/X.690.
117		117
118	ASN_BOOLEAN ASN_INTEGER32 ASN_BIT_STRING ASN_OCTET_STRING ASN_NULL ASN_OBJECT_IDENTIFIER	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	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	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	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	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	123	ASN_ISO646_STRING ASN_GENERAL_STRING ASN_UNIVERSAL_STRING ASN_CHARACTER_STRING ASN_BMP_STRING
…		…
134		134
135	Constants only relevant to SNMP. These are the tag values used by SNMP in	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	136	the C<ASN_APPLICATION> namespace and have the exact numerical value as in
137	BER/RFC 2578.	137	BER/RFC 2578.
138		138
139	SNMP_IPADDRESS SNMP_COUNTER32 SNMP_UNSIGNED32 SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64	139	SNMP_IPADDRESS SNMP_COUNTER32 SNMP_UNSIGNED32 SNMP_GAUGE32
		140	SNMP_TIMETICKS SNMP_OPAQUE SNMP_COUNTER64
140		141
141	=item C<:decode>	142	=item C<:decode>
142		143
143	C<ber_decode> and the match helper functions:	144	C<ber_decode> and the match helper functions:
144		145
		146	ber_decode ber-decode_prefix
145	ber_decode ber_is ber_is_seq ber_is_i32 ber_is_oid	147	ber_is ber_is_seq ber_is_int ber_is_oid
146		148
147	=item C<:encode>	149	=item C<:encode>
148		150
149	C<ber_encode> and the construction helper functions:	151	C<ber_encode> and the construction helper functions:
150		152
151	ber_encode ber_i32	153	ber_encode
		154	ber_int
152		155
153	=back	156	=back
154		157
155	=head2 ASN.1/BER/DER/... BASICS	158	=head2 ASN.1/BER/DER/... BASICS
156		159
157	ASN.1 is a strange language that can be used to describe protocols and	160	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	161	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	162	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.	163	of this module, and is used in SNMP, LDAP or X.509 for example.
161		164
162	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,
163	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
164	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,
165	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
…		…
167		170
168	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,
169	and also have a flag that says whether a value consists of subvalues (is	172	and also have a flag that says whether a value consists of subvalues (is
170	"constructed") or not (is "primitive").	173	"constructed") or not (is "primitive").
171		174
172	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
173	those - for example, you have 32 bit signed integers and 16(!) different	176	of those - for example, you have one integers and 16(!) different
174	string types, but there is no unsigned32 type for example. Different	177	string types, but there is no Unsigned32 type for example. Different
175	applications work around this in different ways, for example, SNMP defines	178	applications work around this in different ways, for example, SNMP defines
176	application-specific Gauge32, Counter32 and Unsigned32, which are mapped	179	application-specific Gauge32, Counter32 and Unsigned32, which are mapped
177	to two different tags: you can distinguish between Counter32 and the	180	to two different tags: you can distinguish between Counter32 and the
178	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.
179		182
…		…
182	=head2 DECODED BER REPRESENTATION	185	=head2 DECODED BER REPRESENTATION
183		186
184	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
185	array-reference):	188	array-reference):
186		189
187	[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
188		198
189	To avoid non-descriptive hardcoded array index numbers, this module	199	To avoid non-descriptive hardcoded array index numbers, this module
190	defines symbolic constants to access these members: C<BER_CLASS>,	200	defines symbolic constants to access these members: C<BER_CLASS>,
191	C<BER_TAG>, C<BER_CONSTRUCTED> and C<BER_DATA>.	201	C<BER_TAG>, C<BER_FLAGS> and C<BER_DATA>.
192		202
193	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
194	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
195	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
196	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.:
197		207
198	$ber = ber_decode $binbuf;	208	$ber = ber_decode $binbuf;
199		209
200	# the following is NOT legal:	210	# the following is NOT legal:
201	$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(!)
202		212
203	# but all of the following are fine:	213	# but all of the following are fine:
204	$ber->[BER_DATA] = "string";	214	$ber->[BER_DATA] = "string";
205	$ber->[BER_DATA] = [ASN_UNIVERSAL, ASN_INTEGER32, 0, 123];	215	$ber->[BER_DATA] = [ASN_UNIVERSAL, ASN_INTEGER, 0, 123];
206	@$ber = (ASN_APPLICATION, SNMP_TIMETICKS, 0, 1000);	216	@$ber = (ASN_APPLICATION, SNMP_TIMETICKS, 0, 1000);
207		217
208	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
209	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
210	implementations, the C<ASN_APPLICATION> namespace which defines tags for	220	implementations, the C<ASN_APPLICATION> namespace which defines tags for
211	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
212	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.
213	for C<CHOICE>) and a private namespace (C<ASN_PRIVATE>).	223	for C<CHOICE>) and a private namespace (C<ASN_PRIVATE>).
214		224
215	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
216	(partial) interpretation of the data value. For example, right now, SNMP	226	(partial) interpretation of the data value. For example, SNMP defines
217	application namespace knowledge ix hardcoded into this module, so it	227	extra tags in the C<ASN_APPLICATION> namespace, and to take full advantage
218	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.
219	integers.
220		229
221	The most common tags in the C<ASN_UNIVERSAL> namespace are	230	The most common tags in the C<ASN_UNIVERSAL> namespace are
222	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>,
223	C<ASN_OBJECT_IDENTIFIER>, C<ASN_SEQUENCE>, C<ASN_SET> and	232	C<ASN_OBJECT_IDENTIFIER>, C<ASN_SEQUENCE>, C<ASN_SET> and
224	C<ASN_IA5_STRING>.	233	C<ASN_IA5_STRING>.
225		234
226	The most common tags in SNMP's C<ASN_APPLICATION> namespace	235	The most common tags in SNMP's C<ASN_APPLICATION> namespace are
227	are C<SNMP_IPADDRESS>, C<SNMP_COUNTER32>, C<SNMP_UNSIGNED32>,	236	C<SNMP_COUNTER32>, C<SNMP_UNSIGNED32>, C<SNMP_TIMETICKS> and
228	C<SNMP_TIMETICKS>, C<SNMP_OPAQUE> and C<SNMP_COUNTER64>.	237	C<SNMP_COUNTER64>.
229		238
230	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
231	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
232	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>,
233	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
234	en-/decode as BER tuples themselves.	243	subvalues which this module will en-/decode as BER tuples themselves.
235		244
236	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
237	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
238	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
239	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
240	interpret the namespace/tag.	249	interpret the namespace/tag.
241		250
242	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
243	string in place of some nice decoded value.	252	string in place of some nice decoded value.
244		253
…		…
246		255
247	=head2 DECODING AND ENCODING	256	=head2 DECODING AND ENCODING
248		257
249	=over	258	=over
250		259
251	=item $tuple = ber_decoded $bindata	260	=item $tuple = ber_decode $bindata[, $profile]
252		261
253	Decodes binary BER data in C<$bindata> and returns the resulting BER	262	Decodes binary BER data in C<$bindata> and returns the resulting BER
254	tuple. Croaks on any decoding error, so the returned C<$tuple> is always	263	tuple. Croaks on any decoding error, so the returned C<$tuple> is always
255	valid.	264	valid.
256		265
		266	How tags are interpreted is defined by the second argument, which must
		267	be a C<Convert::BER::XS::Profile> object. If it is missing, the default
		268	profile will be used (C<$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
257	=item $bindata = ber_encode $tuple	295	=item $bindata = ber_encode $tuple[, $profile]
258		296
259	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).
260		302
261	=back	303	=back
262		304
263	=head2 HELPER FUNCTIONS	305	=head2 HELPER FUNCTIONS
264		306
265	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>
266	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
267	functions, both to match BER tuples and to conmstruct BER tuples:	309	functions, both to match BER tuples and to construct BER tuples:
268		310
269	=head3 MATCH HELPERS	311	=head3 MATCH HELPERS
270		312
271	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
272	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
273	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.
274		316
275	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
276	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
277	tuple reference. in which case they silently fail to match.	319	tuple reference, in which case they silently fail to match.
278		320
279	=over	321	=over
280		322
281	=item $bool = ber_is $tuple, $class, $tag, $constructed, $data	323	=item $bool = ber_is $tuple, $class, $tag, $flags, $data
282		324
283	This takes a BER C<$tuple> and matches its elements agains the privded	325	This takes a BER C<$tuple> and matches its elements against the provided
284	values, all of which are optional - values that are either missing or	326	values, all of which are optional - values that are either missing or
285	C<undef> will be ignored, the others will be matched exactly (e.g. as if	327	C<undef> will be ignored, the others will be matched exactly (e.g. as if
286	you used C<==> or C<eq> (for C<$data>)).	328	you used C<==> or C<eq> (for C<$data>)).
287		329
288	Some examples:	330	Some examples:
…		…
291	orf die "tuple is not an ASN SEQUENCE";	333	orf die "tuple is not an ASN SEQUENCE";
292		334
293	ber_is $tuple, ASN_UNIVERSAL, ASN_NULL	335	ber_is $tuple, ASN_UNIVERSAL, ASN_NULL
294	or die "tuple is not an ASN NULL value";	336	or die "tuple is not an ASN NULL value";
295		337
296	ber_is $tuple, ASN_UNIVERSAL, ASN_INTEGER32, 0, 50	338	ber_is $tuple, ASN_UNIVERSAL, ASN_INTEGER, 0, 50
297	or die "BER integer must be 50";	339	or die "BER integer must be 50";
298		340
299	=item $seq = ber_is_seq $tuple	341	=item $seq = ber_is_seq $tuple
300		342
301	Returns the sequence members (the array of subvalues) if the C<$tuple> is	343	Returns the sequence members (the array of subvalues) if the C<$tuple> is
…		…
308	my $snmp = ber_is_seq $ber	350	my $snmp = ber_is_seq $ber
309	or die "SNMP packet invalid: does not start with SEQUENCE";	351	or die "SNMP packet invalid: does not start with SEQUENCE";
310		352
311	# 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
312		354
313	my $version = ber_is_i32 $snmp->[0]	355	my $version = ber_is_int $snmp->[0]
314	or die "SNMP packet invalid: does not start with version number";	356	or die "SNMP packet invalid: does not start with version number";
315		357
316	=item $bool = ber_is_i32 $tuple, $i32	358	=item $bool = ber_is_int $tuple, $int
317		359
318	Returns a true value if the C<$tuple> represents an ASN INTEGER32 with	360	Returns a true value if the C<$tuple> represents an ASN INTEGER with
319	the value C<$i32>.	361	the value C<$int>.
320		362
321	=item $i32 = ber_is_i32 $tuple	363	=item $int = ber_is_int $tuple
322		364
323	Returns true (and extracts the integer value) if the C<$tuple> is an ASN	365	Returns true (and extracts the integer value) if the C<$tuple> is an
324	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
325	true.	367	but true.
326		368
327	=item $bool = ber_is_oid $tuple, $oid_string	369	=item $bool = ber_is_oid $tuple, $oid_string
328		370
329	Returns true if the C<$tuple> represents an ASN_OBJECT_IDENTIFIER	371	Returns true if the C<$tuple> represents an ASN_OBJECT_IDENTIFIER
330	that exactly matches C<$oid_string>. Example:	372	that exactly matches C<$oid_string>. Example:
…		…
341		383
342	=head3 CONSTRUCTION HELPERS	384	=head3 CONSTRUCTION HELPERS
343		385
344	=over	386	=over
345		387
346	=item $tuple = ber_i32 $value	388	=item $tuple = ber_int $value
347		389
348	Constructs a new C<ASN_INTEGER32> tuple.	390	Constructs a new C<ASN_INTEGER> tuple.
349		391
350	=back	392	=back
351		393
352	=head2 RELATIONSHIP TO L<Convert::BER> and L<Convert::ASN1>	394	=head2 RELATIONSHIP TO L<Convert::BER> and L<Convert::ASN1>
353		395
…		…
366	use Exporter qw(import);	408	use Exporter qw(import);
367		409
368	our $VERSION;	410	our $VERSION;
369		411
370	BEGIN {	412	BEGIN {
371	$VERSION = 0.8;	413	$VERSION = '1.0';
372	XSLoader::load __PACKAGE__, $VERSION;	414	XSLoader::load __PACKAGE__, $VERSION;
373	}	415	}
374		416
375	our %EXPORT_TAGS = (	417	our %EXPORT_TAGS = (
376	const_index => [qw(	418	const_index => [qw(
377	BER_CLASS BER_TAG BER_CONSTRUCTED BER_DATA	419	BER_CLASS BER_TAG BER_FLAGS BER_DATA
378	)],	420	)],
379	const_asn => [qw(	421	const_asn => [qw(
380	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
381	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
382	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
383	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
384	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
385	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
…		…
390	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
391	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
392	BER_TYPE_IPADDRESS BER_TYPE_CROAK	434	BER_TYPE_IPADDRESS BER_TYPE_CROAK
393	)],	435	)],
394	const_snmp => [qw(	436	const_snmp => [qw(
395	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
396	)],	439	)],
397	decode => [qw(	440	decode => [qw(
398	ber_decode	441	ber_decode ber_decode_prefix
399	ber_is ber_is_seq ber_is_i32 ber_is_oid	442	ber_is ber_is_seq ber_is_int ber_is_oid
400	)],	443	)],
401	encode => [qw(	444	encode => [qw(
402	ber_encode	445	ber_encode
403	ber_i32	446	ber_int
404	)],	447	)],
405	);	448	);
406		449
407	our @EXPORT_OK = map @$_, values %EXPORT_TAGS;	450	our @EXPORT_OK = map @$_, values %EXPORT_TAGS;
408		451
409	$EXPORT_TAGS{all} = \@EXPORT_OK;	452	$EXPORT_TAGS{all} = \@EXPORT_OK;
410	$EXPORT_TAGS{const} = [map @{ $EXPORT_TAGS{$_} }, qw(const_index const_asn)];	453	$EXPORT_TAGS{const} = [map @{ $EXPORT_TAGS{$_} }, qw(const_index const_asn)];
411	use Data::Dump; ddx \%EXPORT_TAGS;
412		454
413	=head1 PROFILES	455	=head1 PROFILES
414		456
415	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
416	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"
…		…
556	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
557	error for some types, then C<BER_TYPE_CROAK> is for you.	599	error for some types, then C<BER_TYPE_CROAK> is for you.
558		600
559	=back	601	=back
560		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
561	=cut	617	=cut
562		618
563	our $DEFAULT_PROFILE = new Convert::BER::XS::Profile;	619	our $DEFAULT_PROFILE = new Convert::BER::XS::Profile;
564	our $SNMP_PROFILE = new Convert::BER::XS::Profile;	620
		621	$DEFAULT_PROFILE->_set_default;
565		622
566	# additional SNMP application types	623	# additional SNMP application types
		624	our $SNMP_PROFILE = new Convert::BER::XS::Profile;
		625
567	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_IPADDRESS , BER_TYPE_IPADDRESS);	626	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_IPADDRESS , BER_TYPE_IPADDRESS);
568	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER32 , BER_TYPE_INT);	627	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER32 , BER_TYPE_INT);
569	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT);	628	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_UNSIGNED32, BER_TYPE_INT);
570	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT);	629	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_TIMETICKS , BER_TYPE_INT);
571	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_IPADDRESS);	630	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_OPAQUE , BER_TYPE_IPADDRESS);
572	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT);	631	$SNMP_PROFILE->set (ASN_APPLICATION, SNMP_COUNTER64 , BER_TYPE_INT);
573		632
574	$DEFAULT_PROFILE->_set_default;
575
576	1;	633	1;
577		634
578	=head2 LIMITATIONS/NOTES	635	=head2 LIMITATIONS/NOTES
579		636
580	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
581	only when your perl supports those.	638	only when your perl supports those.
582		639
583	This module does not generally care about ranges, i.e. it will happily	640	This module does not generally care about ranges, i.e. it will happily
584	de-/encode 64 bit integers into an C<ASN_INTEGER32> value, or a negative	641	de-/encode 64 bit integers into an C<ASN_INTEGER> value, or a negative
585	number into an C<SNMP_COUNTER64>.	642	number into an C<SNMP_COUNTER64>.
586		643
587	OBJECT IDENTIFIEERs cannot have unlimited length, although the limit is	644	OBJECT IDENTIFIEERs cannot have unlimited length, although the limit is
588	much larger than e.g. the one imposed by SNMP or other protocols,a nd is	645	much larger than e.g. the one imposed by SNMP or other protocols,a nd is
589	about 4kB.	646	about 4kB.
590		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
591	REAL values are not supported and will currently 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.
592		657
593	This module has undergone little to no testing so far.	658	This module has undergone little to no testing so far.
594		659
595	=head2 ITHREADS SUPPORT	660	=head2 ITHREADS SUPPORT
596		661

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Comparing Convert-BER-XS/XS.pm (file contents): Revision 1.19 by root, Sat Apr 20 14:45:03 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 1.19 by root, Sat Apr 20 14:45:03 2019 UTC vs.
Revision 1.35 by root, Sat Apr 20 21:51:40 2019 UTC