diff --git a/asn1-parser.js b/asn1-parser.js index 53d4318..294273e 100644 --- a/asn1-parser.js +++ b/asn1-parser.js @@ -16,84 +16,93 @@ var PEM = exports.PEM; ASN1.ELOOP = "uASN1.js Error: iterated over 15+ elements (probably a malformed file)"; ASN1.EDEEP = "uASN1.js Error: element nested 20+ layers deep (probably a malformed file)"; // Container Types are Sequence 0x30, Container Array? (0xA0, 0xA1) -// Value Types are Integer 0x02, Null 0x05, Object ID 0x06, String 0x0C, Value Array? (0x82) +// Value Types are Boolean 0x01, Integer 0x02, Null 0x05, Object ID 0x06, String 0x0C, 0x16, 0x13, 0x1e Value Array? (0x82) // Bit String (0x03) and Octet String (0x04) may be values or containers // Sometimes Bit String is used as a container (RSA Pub Spki) ASN1.CTYPES = [ 0x30, 0x31, 0xa0, 0xa1 ]; -ASN1.VTYPES = [ 0x02, 0x05, 0x06, 0x0c, 0x82 ]; -ASN1.parse = function parseAsn1(buf, depth, ws) { - if (!ws) { ws = ''; } - if (!depth) { depth = 0; } - if (depth >= 20) { throw new Error(ASN1.EDEEP); } +ASN1.VTYPES = [ 0x01, 0x02, 0x05, 0x06, 0x0c, 0x82 ]; +ASN1.parse = function parseAsn1Helper(buf) { + //var ws = ' '; + function parseAsn1(buf, depth) { + if (depth.length >= 20) { throw new Error(ASN1.EDEEP); } - var index = 2; // we know, at minimum, data starts after type (0) and lengthSize (1) - var asn1 = { type: buf[0], lengthSize: 0, length: buf[1] }; - var child; - var iters = 0; - var adjust = 0; - var adjustedLen; + var index = 2; // we know, at minimum, data starts after type (0) and lengthSize (1) + var asn1 = { type: buf[0], lengthSize: 0, length: buf[1] }; + var child; + var iters = 0; + var adjust = 0; + var adjustedLen; - // Determine how many bytes the length uses, and what it is - if (0x80 & asn1.length) { - asn1.lengthSize = 0x7f & asn1.length; - // I think that buf->hex->int solves the problem of Endianness... not sure - asn1.length = parseInt(Enc.bufToHex(buf.slice(index, index + asn1.lengthSize)), 16); - index += asn1.lengthSize; - } - - // High-order bit Integers have a leading 0x00 to signify that they are positive. - // Bit Streams use the first byte to signify padding, which x.509 doesn't use. - if (0x00 === buf[index] && (0x02 === asn1.type || 0x03 === asn1.type)) { - // However, 0x00 on its own is a valid number - if (asn1.length > 1) { - index += 1; - adjust = -1; + // Determine how many bytes the length uses, and what it is + if (0x80 & asn1.length) { + asn1.lengthSize = 0x7f & asn1.length; + // I think that buf->hex->int solves the problem of Endianness... not sure + asn1.length = parseInt(Enc.bufToHex(buf.slice(index, index + asn1.lengthSize)), 16); + index += asn1.lengthSize; } - } - adjustedLen = asn1.length + adjust; - //console.warn(ws + '0x' + Enc.numToHex(asn1.type), index, 'len:', asn1.length, asn1); - - function parseChildren(eager) { - asn1.children = []; - //console.warn('1 len:', (2 + asn1.lengthSize + asn1.length), 'idx:', index, 'clen:', 0); - while (iters < 15 && index < (2 + asn1.length + asn1.lengthSize)) { - iters += 1; - child = ASN1.parse(buf.slice(index, index + adjustedLen), (depth || 0) + 1, ws + ' '); - // The numbers don't match up exactly and I don't remember why... - // probably something with adjustedLen or some such, but the tests pass - index += (2 + child.lengthSize + child.length); - //console.warn('2 len:', (2 + asn1.lengthSize + asn1.length), 'idx:', index, 'clen:', (2 + child.lengthSize + child.length)); - if (index > (2 + asn1.lengthSize + asn1.length)) { - if (!eager) { console.error(JSON.stringify(asn1, ASN1._replacer, 2)); } - throw new Error("Parse error: child value length (" + child.length - + ") is greater than remaining parent length (" + (asn1.length - index) - + " = " + asn1.length + " - " + index + ")"); + // High-order bit Integers have a leading 0x00 to signify that they are positive. + // Bit Streams use the first byte to signify padding, which x.509 doesn't use. + if (0x00 === buf[index] && (0x02 === asn1.type || 0x03 === asn1.type)) { + // However, 0x00 on its own is a valid number + if (asn1.length > 1) { + index += 1; + adjust = -1; } - asn1.children.push(child); - //console.warn(ws + '0x' + Enc.numToHex(asn1.type), index, 'len:', asn1.length, asn1); } - if (index !== (2 + asn1.lengthSize + asn1.length)) { - //console.warn('index:', index, 'length:', (2 + asn1.lengthSize + asn1.length)); - throw new Error("premature end-of-file"); - } - if (iters >= 15) { throw new Error(ASN1.ELOOP); } + adjustedLen = asn1.length + adjust; - delete asn1.value; - return asn1; + //console.warn(depth.join(ws) + '0x' + Enc.numToHex(asn1.type), index, 'len:', asn1.length, asn1); + + function parseChildren(eager) { + asn1.children = []; + //console.warn('1 len:', (2 + asn1.lengthSize + asn1.length), 'idx:', index, 'clen:', 0); + while (iters < 15 && index < (2 + asn1.length + asn1.lengthSize)) { + iters += 1; + depth.length += 1; + child = parseAsn1(buf.slice(index, index + adjustedLen), depth); + // The numbers don't match up exactly and I don't remember why... + // probably something with adjustedLen or some such, but the tests pass + index += (2 + child.lengthSize + child.length); + //console.warn('2 len:', (2 + asn1.lengthSize + asn1.length), 'idx:', index, 'clen:', (2 + child.lengthSize + child.length)); + if (index > (2 + asn1.lengthSize + asn1.length)) { + if (!eager) { console.error(JSON.stringify(asn1, ASN1._replacer, 2)); } + throw new Error("Parse error: child value length (" + child.length + + ") is greater than remaining parent length (" + (asn1.length - index) + + " = " + asn1.length + " - " + index + ")"); + } + asn1.children.push(child); + //console.warn(depth.join(ws) + '0x' + Enc.numToHex(asn1.type), index, 'len:', asn1.length, asn1); + } + if (index !== (2 + asn1.lengthSize + asn1.length)) { + //console.warn('index:', index, 'length:', (2 + asn1.lengthSize + asn1.length)); + throw new Error("premature end-of-file"); + } + if (iters >= 15) { throw new Error(ASN1.ELOOP); } + + delete asn1.value; + return asn1; + } + + // Recurse into types that are _always_ containers + if (-1 !== ASN1.CTYPES.indexOf(asn1.type)) { return parseChildren(); } + + // Return types that are _always_ values + asn1.value = buf.slice(index, index + adjustedLen); + if (-1 !== ASN1.VTYPES.indexOf(asn1.type)) { return asn1; } + + // For ambigious / unknown types, recurse and return on failure + // (and return child array size to zero) + try { return parseChildren(true); } + catch(e) { asn1.children.length = 0; return asn1; } } - // Recurse into types that are _always_ containers - if (-1 !== ASN1.CTYPES.indexOf(asn1.type)) { return parseChildren(); } - - // Return types that are _always_ values - asn1.value = buf.slice(index, index + adjustedLen); - if (-1 !== ASN1.VTYPES.indexOf(asn1.type)) { return asn1; } - - // For ambigious / unknown types, recurse and return on failure - // (and return child array size to zero) - try { return parseChildren(true); } - catch(e) { asn1.children.length = 0; return asn1; } + var asn1 = parseAsn1(buf, []); + var len = buf.byteLength || buf.length; + if (len !== 2 + asn1.lengthSize + asn1.length) { + throw new Error("Length of buffer does not match length of ASN.1 sequence."); + } + return asn1; }; ASN1._replacer = function (k, v) { if ('type' === k) { return '0x' + Enc.numToHex(v); } diff --git a/index.html b/index.html index 7e4fb3a..e476f1f 100644 --- a/index.html +++ b/index.html @@ -30,11 +30,18 @@ rMjgyCokrnjDft6Y/YnA4A50yZe7CnFsqeDcpnPbubP6cpYiVcnevNIYyg== function convert() { console.log('keyup'); - var pem = PEM.parseBlock(document.querySelector('.js-input').value); - var hex = Enc.bufToHex(pem.der); - document.querySelector('.js-hex').innerText = hex - .match(/.{2}/g).join(' ').match(/.{1,24}/g).join(' ').match(/.{1,50}/g).join('\n'); - var json = ASN1.parse(pem.der); + var json; + + try { + var pem = PEM.parseBlock(document.querySelector('.js-input').value); + var hex = Enc.bufToHex(pem.der); + document.querySelector('.js-hex').innerText = hex + .match(/.{2}/g).join(' ').match(/.{1,24}/g).join(' ').match(/.{1,50}/g).join('\n'); + json = ASN1.parse(pem.der); + } catch(e) { + json = { error: { message: e.message } }; + } + document.querySelector('.js-json').innerText = JSON.stringify(json, ASN1._replacer, 2); } diff --git a/package.json b/package.json index 9d3a9e4..0fbcaa8 100644 --- a/package.json +++ b/package.json @@ -1,6 +1,6 @@ { "name": "asn1-parser", - "version": "1.1.1", + "version": "1.1.2", "description": "An ASN.1 parser in less than 100 lines of Vanilla JavaScript, part of the Bluecrypt suite.", "homepage": "https://git.coolaj86.com/coolaj86/asn1-parser.js", "main": "asn1-parser.js",