1 #!/usr/bin/perl -w
2 # SPDX-License-Identifier: GPL-2.0-or-later
3 #
4 # Build a static ASN.1 Object Identified (OID)
5 #
6 # Copyright (C) 2012 Red Hat, Inc. All Rights
7 # Written by David Howells (dhowells@redhat.co
8 #
9
10 use strict;
11 use Cwd qw(abs_path);
12
13 my @names = ();
14 my @oids = ();
15
16 if ($#ARGV != 1) {
17 print STDERR "Format: ", $0, " <in-h-file>
18 exit(2);
19 }
20
21 my $abs_srctree = abs_path($ENV{'srctree'});
22
23 #
24 # Open the file to read from
25 #
26 open IN_FILE, "<$ARGV[0]" || die;
27 while (<IN_FILE>) {
28 chomp;
29 if (m!\s+OID_([a-zA-z][a-zA-Z0-9_]+),\s+/[
30 push @names, $1;
31 push @oids, $2;
32 }
33 }
34 close IN_FILE || die;
35
36 #
37 # Open the files to write into
38 #
39 open C_FILE, ">$ARGV[1]" or die;
40 print C_FILE "/*\n";
41 my $scriptname = $0;
42 $scriptname =~ s#^\Q$abs_srctree/\E##;
43 print C_FILE " * Automatically generated by ",
44 print C_FILE " */\n";
45
46 #
47 # Split the data up into separate lists and al
48 # encoded data arrays.
49 #
50 my @indices = ();
51 my @lengths = ();
52 my $total_length = 0;
53
54 for (my $i = 0; $i <= $#names; $i++) {
55 my $name = $names[$i];
56 my $oid = $oids[$i];
57
58 my @components = split(/[.]/, $oid);
59
60 # Determine the encoded length of this OID
61 my $size = $#components;
62 for (my $loop = 2; $loop <= $#components;
63 my $c = $components[$loop];
64
65 # We will base128 encode the number
66 my $tmp = ($c == 0) ? 0 : int(log($c)/
67 $tmp = int($tmp / 7);
68 $size += $tmp;
69 }
70 push @lengths, $size;
71 push @indices, $total_length;
72 $total_length += $size;
73 }
74
75 #
76 # Emit the look-up-by-OID index table
77 #
78 print C_FILE "\n";
79 if ($total_length <= 255) {
80 print C_FILE "static const unsigned char o
81 } else {
82 print C_FILE "static const unsigned short
83 }
84 for (my $i = 0; $i <= $#names; $i++) {
85 print C_FILE "\t[OID_", $names[$i], "] = "
86 }
87 print C_FILE "\t[OID__NR] = ", $total_length,
88 print C_FILE "};\n";
89
90 #
91 # Encode the OIDs
92 #
93 my @encoded_oids = ();
94
95 for (my $i = 0; $i <= $#names; $i++) {
96 my @octets = ();
97
98 my @components = split(/[.]/, $oids[$i]);
99
100 push @octets, $components[0] * 40 + $compo
101
102 for (my $loop = 2; $loop <= $#components;
103 my $c = $components[$loop];
104
105 # Base128 encode the number
106 my $tmp = ($c == 0) ? 0 : int(log($c)/
107 $tmp = int($tmp / 7);
108
109 for (; $tmp > 0; $tmp--) {
110 push @octets, (($c >> $tmp * 7) &
111 }
112 push @octets, $c & 0x7f;
113 }
114
115 push @encoded_oids, \@octets;
116 }
117
118 #
119 # Create a hash value for each OID
120 #
121 my @hash_values = ();
122 for (my $i = 0; $i <= $#names; $i++) {
123 my @octets = @{$encoded_oids[$i]};
124
125 my $hash = $#octets;
126 foreach (@octets) {
127 $hash += $_ * 33;
128 }
129
130 $hash = ($hash >> 24) ^ ($hash >> 16) ^ ($
131
132 push @hash_values, $hash & 0xff;
133 }
134
135 #
136 # Emit the OID data
137 #
138 print C_FILE "\n";
139 print C_FILE "static const unsigned char oid_d
140 for (my $i = 0; $i <= $#names; $i++) {
141 my @octets = @{$encoded_oids[$i]};
142 print C_FILE "\t";
143 print C_FILE $_, ", " foreach (@octets);
144 print C_FILE "\t// ", $names[$i];
145 print C_FILE "\n";
146 }
147 print C_FILE "};\n";
148
149 #
150 # Build the search index table (ordered by len
151 #
152 my @index_table = ( 0 .. $#names );
153
154 @index_table = sort {
155 my @octets_a = @{$encoded_oids[$a]};
156 my @octets_b = @{$encoded_oids[$b]};
157
158 return $hash_values[$a] <=> $hash_values[$
159 if ($hash_values[$a] != $hash_values[$
160 return $#octets_a <=> $#octets_b
161 if ($#octets_a != $#octets_b);
162 for (my $i = $#octets_a; $i >= 0; $i--) {
163 return $octets_a[$i] <=> $octets_b[$i]
164 if ($octets_a[$i] != $octets_b[$i]
165 }
166 return 0;
167
168 } @index_table;
169
170 #
171 # Emit the search index and hash value table
172 #
173 print C_FILE "\n";
174 print C_FILE "static const struct {\n";
175 print C_FILE "\tunsigned char hash;\n";
176 if ($#names <= 255) {
177 print C_FILE "\tenum OID oid : 8;\n";
178 } else {
179 print C_FILE "\tenum OID oid : 16;\n";
180 }
181 print C_FILE "} oid_search_table[OID__NR] = {\
182 for (my $i = 0; $i <= $#names; $i++) {
183 my @octets = @{$encoded_oids[$index_table[
184 printf(C_FILE "\t[%3u] = { %3u, OID_%-35s
185 $i,
186 $hash_values[$index_table[$i]],
187 $names[$index_table[$i]]);
188 printf C_FILE "%02x", $_ foreach (@octets)
189 print C_FILE "\n";
190 }
191 print C_FILE "};\n";
192
193 #
194 # Emit the OID debugging name table
195 #
196 #print C_FILE "\n";
197 #print C_FILE "const char *const oid_name_tabl
198 #
199 #for (my $i = 0; $i <= $#names; $i++) {
200 # print C_FILE "\t\"", $names[$i], "\",\n"
201 #}
202 #print C_FILE "\t\"Unknown-OID\"\n";
203 #print C_FILE "};\n";
204
205 #
206 # Polish off
207 #
208 close C_FILE or die;
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