parseRFC.js at github-56 · lapo.it/asn1js

lapo.it / asn1js
JavaScript generic ASN.1 parser (mirror)
asn1js / parseRFC.js
at github-56 16 kB view raw
  1#! /usr/bin/env node
  2'use strict';
  3
  4const
  5    fs = require('fs'),
  6    patches = { // to fix some known RFCs' ASN.1 syntax errors
  7        0: [
  8            [ /\n\n[A-Z].*\n\f\n[A-Z].*\n\n/g, '' ], // page change
  9        ],
 10        2459: [ // currently unsupported
 11            [ 'videotex (8) } (0..ub-integer-options)', 'videotex (8) }' ],
 12            [ /OBJECT IDENTIFIER \( id-qt-cps \| id-qt-unotice \)/g, 'OBJECT IDENTIFIER' ],
 13            [ /SIGNED \{ (SEQUENCE \{[^}]+\})\s*\}/g, 'SEQUENCE { toBeSigned $1, algorithm AlgorithmIdentifier, signature BIT STRING }' ],
 14            [ /EXTENSION\.&[^,]+/g, 'OBJECT IDENTIFIER'],
 15        ],
 16        3161: [ // actual syntax errors
 17            [ /--.*}/g, '}' ],
 18            [ /^( +)--.*\n(?:\1 .*\n)+/mg, '' ],
 19            [ /addInfoNotAvailable \(17\)/g, '$&,' ],
 20        ],
 21        5280: [ // currently unsupported
 22            [ 'videotex     (8) } (0..ub-integer-options)', 'videotex     (8) }' ],
 23            [ /OBJECT IDENTIFIER \( id-qt-cps \| id-qt-unotice \)/g, 'OBJECT IDENTIFIER' ],
 24        ],
 25    };
 26
 27let asn1;
 28let currentMod;
 29
 30function Parser(enc, pos) {
 31    this.enc = enc;
 32    this.pos = pos;
 33    this.start = pos;
 34}
 35Parser.prototype.getChar = function (pos) {
 36    if (pos === undefined)
 37        pos = this.pos++;
 38    if (pos >= this.enc.length)
 39        throw 'Requesting byte offset ' + pos + ' on a stream of length ' + this.enc.length;
 40    return this.enc.charAt(pos);
 41};
 42Parser.prototype.exception = function (s, pos) {
 43    if (pos == undefined) pos = this.pos;
 44    let from = Math.max(pos - 30, this.start);
 45    let to   = Math.min(pos + 30, this.enc.length);
 46    let ctx  = '';
 47    let arrow = '';
 48    let i = from;
 49    for (; i < pos; ++i) {
 50        ctx += this.getChar(i);
 51        arrow += ' ';
 52    }
 53    ctx += this.getChar(i++);
 54    arrow += '^';
 55    for (; i < to; ++i)
 56        ctx += this.getChar(i);
 57    throw new Error('[position ' + pos + '] ' + s + '\n' + ctx.replace(/\s/g, ' ') + '\n' + arrow);
 58};
 59Parser.prototype.peek = function () {
 60    return (typeof this.enc == "string") ? this.enc.charCodeAt(this.pos) : this.enc[this.pos];
 61};
 62Parser.prototype.peekChar = function () {
 63    return (typeof this.enc == "string") ? this.enc.charAt(this.pos) : String.fromCharCode(this.enc[this.pos]);
 64};
 65Parser.prototype.isWhitespace = function () {
 66    let c = this.peekChar();
 67    return c == ' ' || c == '\n';
 68};
 69Parser.prototype.isDigit = function () {
 70    let c = this.peekChar();
 71    return c >= '0' && c <= '9';
 72};
 73// const reWhitespace = /(?:\s|--(?:[}-]?[^\n}-])*(?:\n|--))*/y;
 74const reWhitespace = /(?:\s|--(?:-?[^\n-])*(?:\n|--))*/my;
 75Parser.prototype.skipWhitespace = function () {
 76    reWhitespace.lastIndex = this.pos;
 77    let s = reWhitespace.exec(this.enc);
 78    if (s)
 79        this.pos = reWhitespace.lastIndex;
 80};
 81// DefStream.prototype.eat = function (str) {
 82//     for (let i = 0; i < str.length; ++i) {
 83//         let c = this.getChar();
 84//         if (c != str.charAt(i))
 85//             throw new Error("Found '" + c + "', was expecting '" + str.charAt(i) + "'");
 86//     }
 87// };
 88Parser.prototype.getRegEx = function (type, re) {
 89    this.skipWhitespace();
 90    re.lastIndex = this.pos;
 91    let s = re.exec(this.enc); //TODO: does not work with typed arrays
 92    if (!s)
 93        this.exception("Found '" + this.peekChar() + "', was expecting a " + type);
 94    s = s[0];
 95    // console.log('[debug] getRexEx@' + this.pos + ' = ' + s);
 96    this.pos = re.lastIndex;
 97    this.skipWhitespace();
 98    return s;
 99};
100const reIdentifier = /[a-zA-Z](?:[-]?[a-zA-Z0-9])*/y;
101Parser.prototype.parseIdentifier = function () {
102    let id = this.getRegEx('identifier', reIdentifier);
103    // console.log('[debug] parseIdentifier = ' + id);
104    return id;
105};
106const reNumber = /0|[1-9][0-9]*/y;
107Parser.prototype.parseNumber = function () {
108    let id = this.getRegEx('number', reNumber);
109    // console.log('[debug] parseNumber = ' + id);
110    return id;
111};
112const reToken = /[(){},[\];]|::=|OPTIONAL|DEFAULT|NULL|TRUE|FALSE|\.\.|OF|SIZE|MIN|MAX|DEFINED BY|DEFINITIONS|TAGS|BEGIN|EXPORTS|IMPORTS|FROM|END/y;
113Parser.prototype.parseToken = function () {
114    let tok = this.getRegEx('token', reToken);
115    return tok;
116};
117Parser.prototype.tryToken = function (expect) {
118    let p = this.pos;
119    let t;
120    try { t = this.parseToken(); } catch (e) { /*ignore*/ }
121    // console.log('[debug] tryToken(' + expect + ') = ' + t);
122    if (t == expect)
123        return true;
124    else {
125        this.pos = p;
126        return false;
127    }
128};
129Parser.prototype.expectToken = function (expect) {
130    let p = this.pos;
131    let t;
132    try { t = this.parseToken(); }
133    catch (e) { console.log('[debug] expectToken', e); }
134    // console.log('[debug] expectToken(' + expect + ') = ' + t);
135    if (t != expect) {
136        this.pos = p;
137        this.exception("Found '" + t + "', was expecting '" + expect + "'");
138    }
139};
140Parser.prototype.parseNumberOrValue = function () {
141    if (this.isDigit())
142        return +this.parseNumber();
143    return this.parseIdentifier();
144};
145Parser.prototype.parseRange = function () {
146    let min = this.tryToken('MIN') ? 'MIN' : this.parseNumberOrValue();
147    if (this.tryToken('..')) {
148        let max = this.tryToken('MAX') ? 'MAX' : this.parseNumberOrValue();
149        return [min, max];
150    }
151    return min;
152};
153const reType = /ANY|BOOLEAN|INTEGER|(?:BIT|OCTET)\s+STRING|OBJECT\s+IDENTIFIER|SEQUENCE|SET|CHOICE|ENUMERATED|(?:Generalized|UTC)Time|(?:BMP|General|Graphic|IA5|ISO64|Numeric|Printable|Teletex|T61|Universal|UTF8|Videotex|Visible)String/y;
154Parser.prototype.parseBuiltinType = function () {
155    let x = {
156        name: this.getRegEx('type', reType),
157        type: 'builtin',
158    };
159    // console.log('[debug] parseType = ' + x.name);
160    try {
161        switch (x.name) {
162        case 'ANY':
163            if (this.tryToken('DEFINED BY'))
164                x.definedBy = this.parseIdentifier();
165            break;
166        case 'BOOLEAN':
167        case 'OCTET STRING':
168        case 'OBJECT IDENTIFIER':
169            break;
170        case 'CHOICE':
171            x.content = this.parseElementTypeList();
172            break;
173        case 'SEQUENCE':
174        case 'SET':
175            if (this.peekChar() == '{') {
176                x.content = this.parseElementTypeList();
177            } else {
178                x.typeOf = 1;
179                if (this.tryToken('SIZE')) {
180                    this.expectToken('(');
181                    x.size = this.parseRange();
182                    this.expectToken(')');
183                }
184                this.expectToken('OF');
185                x.content = [this.parseType()];
186            }
187            break;
188        case 'INTEGER':
189            if (this.tryToken('(')) {
190                x.range = this.parseRange();
191                this.expectToken(')');
192            }
193            // falls through
194        case 'ENUMERATED':
195        case 'BIT STRING':
196            if (this.tryToken('{')) {
197                x.content = {};
198                do {
199                    let id = this.parseIdentifier();
200                    this.expectToken('(');
201                    let val = this.parseNumber(); //TODO: signed
202                    this.expectToken(')');
203                    x.content[id] = +val;
204                } while (this.tryToken(','));
205                this.expectToken('}');
206            }
207            break;
208        case 'BMPString':
209        case 'GeneralString':
210        case 'GraphicString':
211        case 'IA5String':
212        case 'ISO646String':
213        case 'NumericString':
214        case 'PrintableString':
215        case 'TeletexString':
216        case 'T61String':
217        case 'UniversalString':
218        case 'UTF8String':
219        case 'VideotexString':
220        case 'VisibleString':
221            if (this.tryToken('(')) {
222                if (this.tryToken('SIZE')) {
223                    this.expectToken('(');
224                    x.size = this.parseRange();
225                    this.expectToken(')');
226                }
227                this.expectToken(')');
228            }
229            break;
230        default:
231            x.content = 'TODO:unknown';
232        }
233    } catch (e) {
234        console.log('[debug] parseBuiltinType content', e);
235        x.content = 'TODO:exception';
236    }
237    return x;
238};
239const reTagClass = /UNIVERSAL|APPLICATION|PRIVATE|/y;
240const reTagType = /IMPLICIT|EXPLICIT|/y;
241Parser.prototype.parseTaggedType = function () {
242    this.expectToken('[');
243    let tagClass = this.getRegEx('class', reTagClass) || 'CONTEXT'; //TODO: use module defaults
244    let t = this.parseNumber();
245    this.expectToken(']');
246    let plicit = this.getRegEx('explicit/implicit', reTagType);
247    if (plicit == '') plicit = currentMod.tagDefault;
248    let x = this.parseType();
249    return {
250        name: '[' + t + ']',
251        type: 'tag',
252        "class": tagClass,
253        explicit: (plicit == 'EXPLICIT'),
254        content: [{ name: '', type: x }],
255    };
256};
257Parser.prototype.parseType = function () {
258    if (this.peekChar() == '[')
259        return this.parseTaggedType();
260    let p = this.pos;
261    try {
262        return this.parseBuiltinType();
263    } catch (e) {
264        // console.log('[debug] parseAssignment failed on parseType', e);
265        this.pos = p;
266        let x = {
267            name: this.parseIdentifier(),
268            type: 'defined',
269        };
270        // let from = searchImportedType(x.name);
271        // if (from)
272        //     x.module = from;
273        return x;
274        //TODO "restricted string type"
275    }
276};
277Parser.prototype.parseValueBoolean = function () {
278    let p = this.pos;
279    let t = this.parseToken();
280    if (t == 'TRUE')
281        return true;
282    if (t == 'FALSE')
283        return false;
284    this.pos = p;
285    this.exception("Found '" + t + "', was expecting a boolean");
286};
287function searchImportedValue(id) {
288    for (let imp of Object.values(currentMod.imports))
289        for (let name of imp.types)
290            if (name == id) {
291                if (!(imp.oid in asn1))
292                    throw new Error('Cannot find module: ' + imp.oid + ' ' + id);
293                if (id in asn1[imp.oid].values)
294                    return asn1[imp.oid].values[id];
295                throw new Error('Cannot find imported value: ' + imp.oid + ' ' + id);
296            }
297    throw new Error('Cannot find imported value in any module: ' + id);
298}
299Parser.prototype.parseValueOID = function () {
300    this.expectToken('{');
301    let v = '';
302    while (!this.tryToken('}')) {
303        let p = this.pos;
304        let val;
305        if (this.isDigit())
306            val = this.parseNumber();
307        else {
308            this.pos = p;
309            let id = this.parseIdentifier();
310            if (this.tryToken('(')) {
311                val = this.parseNumber();
312                this.expectToken(')');
313            } else {
314                if (id in currentMod.values) // defined in local module
315                    val = currentMod.values[id].value;
316                else
317                    val = searchImportedValue(id);
318            }
319        }
320        if (v.length) v += '.';
321        v += val;
322    }
323    return v;
324};
325Parser.prototype.parseValue = function () {
326    let c = this.peekChar();
327    if (c == '{')
328        return this.parseValueOID();
329    if (c >= '0' && c <= '9')
330        return +this.parseNumber();
331    if (c == '-')
332        return -this.parseNumber();
333    let p = this.pos;
334    try {
335        switch (this.parseToken()) {
336        case 'TRUE':
337            return true;
338        case 'FALSE':
339            return false;
340        case 'NULL':
341            return null;
342        }
343    } catch (e) {
344        this.pos = p;
345    }
346    p = this.pos;
347    try {
348        return this.parseIdentifier();
349    } catch (e) {
350        this.pos = p;
351    }
352    this.exception('Unknown value type.');
353};
354/*DefStream.prototype.parseValue = function (type) {
355    console.log('[debug] parseValue type:', type);
356    if (type.type == 'defined') {
357        if (!(type.name in types))
358            this.exception("Missing type: " + type.name);
359        type = types[type.name];
360    }
361    switch (type.name) {
362        case 'BOOLEAN':
363            return this.parseValueBoolean();
364        case 'OBJECT IDENTIFIER':
365            return this.parseValueOID();
366        default:
367            console.log('[debug] parseValue unknown:', type);
368            return 'TODO:value';
369    }
370};*/
371Parser.prototype.parseElementType = function () {
372    let x = Object.assign({ id: this.parseIdentifier() }, this.parseType());
373    // console.log('[debug] parseElementType 1:', x);
374    if (this.tryToken('OPTIONAL'))
375        x.optional = true;
376    if (this.tryToken('DEFAULT'))
377        x.default = this.parseValue(x.type);
378        // console.log('[debug] parseElementType 2:', x);
379    return x;
380};
381Parser.prototype.parseElementTypeList = function () {
382    let v = [];
383    this.expectToken('{');
384    do {
385        v.push(this.parseElementType());
386    } while (this.tryToken(','));
387    this.expectToken('}');
388    return v;
389};
390Parser.prototype.parseAssignment = function () {
391    let name = this.parseIdentifier();
392    if (this.tryToken('::=')) { // type assignment
393        // console.log('type name', name);
394        let type = this.parseType();
395        currentMod.types[name] = { name, type };
396        return currentMod.types[name];
397    } else { // value assignment
398        // console.log('value name', name);
399        let type = this.parseType();
400        // console.log('[debug] parseAssignment type:', type);
401        this.expectToken('::=');
402        let value = this.parseValue(type);
403        currentMod.values[name] = { name, type, value };
404        return currentMod.values[name];
405    }
406};
407Parser.prototype.parseModuleIdentifier = function () {
408    return {
409        name: this.parseIdentifier(),
410        oid: this.parseValueOID(),
411    };
412};
413Parser.prototype.parseSymbolsImported = function () {
414    let imports = {};
415    do {
416        let l = [];
417        do {
418            l.push(this.parseIdentifier());
419        } while (this.tryToken(','));
420        this.expectToken('FROM');
421        let mod = this.parseModuleIdentifier();
422        mod.types = l;
423        imports[mod.oid] = mod;
424    } while (this.peekChar() != ';');
425    return imports;
426};
427const reTagDefault = /(AUTOMATIC|IMPLICIT|EXPLICIT) TAGS|/y;
428Parser.prototype.parseModuleDefinition = function (file) {
429    let mod = this.parseModuleIdentifier();
430    currentMod = mod; // for deeply nested parsers
431    mod.source = file;
432    this.expectToken('DEFINITIONS');
433    mod.tagDefault = this.getRegEx('tag default', reTagDefault).split(' ')[0];
434    this.expectToken('::=');
435    this.expectToken('BEGIN');
436    //TODO this.tryToken('EXPORTS')
437    if (this.tryToken('IMPORTS')) {
438        mod.imports = this.parseSymbolsImported();
439        this.expectToken(';');
440    }
441    mod.values = {};
442    mod.types = {};
443    while (!this.tryToken('END'))
444        this.parseAssignment();
445    return mod;
446};
447
448let s = fs.readFileSync(process.argv[2], 'utf8');
449let num = /^Request for Comments: ([0-9]+)/m.exec(s)[1];
450console.log('RFC:', num);
451for (let p of patches[0])
452    s = s.replace(p[0], p[1]);
453if (num in patches)
454    for (let p of patches[num])
455        s = s.replace(p[0], p[1]);
456// fs.writeFileSync('rfc3161_patched.txt', s, 'utf8');
457// console.log(s);
458asn1 = JSON.parse(fs.readFileSync(process.argv[3], 'utf8'));
459const reModuleDefinition = /\s[A-Z](?:[-]?[a-zA-Z0-9])*\s*\{[^}]+\}\s*DEFINITIONS/gm;
460let m;
461while ((m = reModuleDefinition.exec(s))) {
462    new Parser(s, m.index).parseModuleDefinition(process.argv[2]);
463    console.log('Module:', currentMod.name);
464    // fs.writeFileSync('rfc' + num + '.json', JSON.stringify(currentMod, null, 2) + '\n', 'utf8');
465    asn1[currentMod.oid] = currentMod;
466}
467/*asn1 = Object.keys(asn1).sort().reduce(
468    (obj, key) => { 
469        obj[key] = asn1[key];
470        return obj;
471    }, 
472    {}
473);*/
474fs.writeFileSync(process.argv[3], JSON.stringify(asn1, null, 2) + '\n', 'utf8');
475// console.log('Module:', mod);
476/*while ((idx = s.indexOf('::=', idx + 1)) >= 0) {
477    let line = s.lastIndexOf('\n', idx) + 1;
478    // console.log('[line] ' + s.slice(line, line+30));
479    try {
480        let a = new DefStream(s, line).parseAssignment();
481        // console.log('[assignment]', util.inspect(a, {showHidden: false, depth: null, colors: true}));
482    } catch (e) {
483        console.log('Error:', e);
484    }
485}*/
486console.log('Done.');