wildduck/imap-core/lib/handler/imap-parser.js
2017-03-05 23:45:50 +02:00

636 lines
26 KiB
JavaScript

/* eslint new-cap: 0 */
'use strict';
let imapFormalSyntax = require('./imap-formal-syntax');
class TokenParser {
constructor(parent, startPos, str, options) {
this.str = (str || '').toString();
this.options = options || {};
this.parent = parent;
this.tree = this.currentNode = this.createNode();
this.pos = startPos || 0;
this.currentNode.type = 'TREE';
this.state = 'NORMAL';
this.processString();
}
getAttributes() {
let attributes = [],
branch = attributes;
let walk = function (node) {
let curBranch = branch;
let elm;
let partial;
if (!node.closed && node.type === 'SEQUENCE' && node.value === '*') {
node.closed = true;
node.type = 'ATOM';
}
// If the node was never closed, throw it
if (!node.closed) {
throw new Error('Unexpected end of input at position ' + (this.pos + this.str.length - 1));
}
let type = (node.type || '').toString().toUpperCase();
switch (type) {
case 'LITERAL':
case 'STRING':
case 'SEQUENCE':
elm = {
type: node.type.toUpperCase(),
value: node.value
};
branch.push(elm);
break;
case 'ATOM':
if (node.value.toUpperCase() === 'NIL') {
branch.push(null);
break;
}
elm = {
type: node.type.toUpperCase(),
value: node.value
};
branch.push(elm);
break;
case 'SECTION':
branch = branch[branch.length - 1].section = [];
break;
case 'LIST':
elm = [];
branch.push(elm);
branch = elm;
break;
case 'PARTIAL':
partial = node.value.split('.').map(Number);
branch[branch.length - 1].partial = partial;
break;
}
node.childNodes.forEach(childNode => walk(childNode));
branch = curBranch;
}.bind(this);
walk(this.tree);
return attributes;
}
createNode(parentNode, startPos) {
let node = {
childNodes: [],
type: false,
value: '',
closed: true
};
if (parentNode) {
node.parentNode = parentNode;
}
if (typeof startPos === 'number') {
node.startPos = startPos;
}
if (parentNode) {
parentNode.childNodes.push(node);
}
return node;
}
processString() {
let chr, i, len,
checkSP = function () {
// jump to the next non whitespace pos
while (this.str.charAt(i + 1) === ' ') {
i++;
}
}.bind(this);
for (i = 0, len = this.str.length; i < len; i++) {
chr = this.str.charAt(i);
switch (this.state) {
case 'NORMAL':
switch (chr) {
// DQUOTE starts a new string
case '"':
this.currentNode = this.createNode(this.currentNode, this.pos + i);
this.currentNode.type = 'string';
this.state = 'STRING';
this.currentNode.closed = false;
break;
// ( starts a new list
case '(':
this.currentNode = this.createNode(this.currentNode, this.pos + i);
this.currentNode.type = 'LIST';
this.currentNode.closed = false;
break;
// ) closes a list
case ')':
if (this.currentNode.type !== 'LIST') {
throw new Error('Unexpected list terminator ) at position ' + (this.pos + i));
}
this.currentNode.closed = true;
this.currentNode.endPos = this.pos + i;
this.currentNode = this.currentNode.parentNode;
checkSP();
break;
// ] closes section group
case ']':
if (this.currentNode.type !== 'SECTION') {
throw new Error('Unexpected section terminator ] at position ' + (this.pos + i));
}
this.currentNode.closed = true;
this.currentNode.endPos = this.pos + i;
this.currentNode = this.currentNode.parentNode;
checkSP();
break;
// < starts a new partial
case '<':
if (this.str.charAt(i - 1) !== ']') {
this.currentNode = this.createNode(this.currentNode, this.pos + i);
this.currentNode.type = 'ATOM';
this.currentNode.value = chr;
this.state = 'ATOM';
} else {
this.currentNode = this.createNode(this.currentNode, this.pos + i);
this.currentNode.type = 'PARTIAL';
this.state = 'PARTIAL';
this.currentNode.closed = false;
}
break;
// { starts a new literal
case '{':
this.currentNode = this.createNode(this.currentNode, this.pos + i);
this.currentNode.type = 'LITERAL';
this.state = 'LITERAL';
this.currentNode.closed = false;
break;
// ( starts a new sequence
case '*':
this.currentNode = this.createNode(this.currentNode, this.pos + i);
this.currentNode.type = 'SEQUENCE';
this.currentNode.value = chr;
this.currentNode.closed = false;
this.state = 'SEQUENCE';
break;
// normally a space should never occur
case ' ':
// just ignore
break;
// [ starts section
case '[':
// If it is the *first* element after response command, then process as a response argument list
if (['OK', 'NO', 'BAD', 'BYE', 'PREAUTH'].indexOf(this.parent.command.toUpperCase()) >= 0 && this.currentNode === this.tree) {
this.currentNode.endPos = this.pos + i;
this.currentNode = this.createNode(this.currentNode, this.pos + i);
this.currentNode.type = 'ATOM';
this.currentNode = this.createNode(this.currentNode, this.pos + i);
this.currentNode.type = 'SECTION';
this.currentNode.closed = false;
this.state = 'NORMAL';
// RFC2221 defines a response code REFERRAL whose payload is an
// RFC2192/RFC5092 imapurl that we will try to parse as an ATOM but
// fail quite badly at parsing. Since the imapurl is such a unique
// (and crazy) term, we just specialize that case here.
if (this.str.substr(i + 1, 9).toUpperCase() === 'REFERRAL ') {
// create the REFERRAL atom
this.currentNode = this.createNode(this.currentNode, this.pos + i + 1);
this.currentNode.type = 'ATOM';
this.currentNode.endPos = this.pos + i + 8;
this.currentNode.value = 'REFERRAL';
this.currentNode = this.currentNode.parentNode;
// eat all the way through the ] to be the IMAPURL token.
this.currentNode = this.createNode(this.currentNode, this.pos + i + 10);
// just call this an ATOM, even though IMAPURL might be more correct
this.currentNode.type = 'ATOM';
// jump i to the ']'
i = this.str.indexOf(']', i + 10);
this.currentNode.endPos = this.pos + i - 1;
this.currentNode.value = this.str.substring(this.currentNode.startPos - this.pos,
this.currentNode.endPos - this.pos + 1);
this.currentNode = this.currentNode.parentNode;
// close out the SECTION
this.currentNode.closed = true;
this.currentNode = this.currentNode.parentNode;
checkSP();
}
break;
}
/* falls through */
default:
// Any ATOM supported char starts a new Atom sequence, otherwise throw an error
// Allow \ as the first char for atom to support system flags
// Allow % to support LIST '' %
if (imapFormalSyntax['ATOM-CHAR']().indexOf(chr) < 0 && chr !== '\\' && chr !== '%') {
throw new Error('Unexpected char at position ' + (this.pos + i));
}
this.currentNode = this.createNode(this.currentNode, this.pos + i);
this.currentNode.type = 'ATOM';
this.currentNode.value = chr;
this.state = 'ATOM';
break;
}
break;
case 'ATOM':
// space finishes an atom
if (chr === ' ') {
this.currentNode.endPos = this.pos + i - 1;
this.currentNode = this.currentNode.parentNode;
this.state = 'NORMAL';
break;
}
//
if (
this.currentNode.parentNode &&
(
(chr === ')' && this.currentNode.parentNode.type === 'LIST') ||
(chr === ']' && this.currentNode.parentNode.type === 'SECTION')
)
) {
this.currentNode.endPos = this.pos + i - 1;
this.currentNode = this.currentNode.parentNode;
this.currentNode.closed = true;
this.currentNode.endPos = this.pos + i;
this.currentNode = this.currentNode.parentNode;
this.state = 'NORMAL';
checkSP();
break;
}
if ((chr === ',' || chr === ':') && this.currentNode.value.match(/^\d+$/)) {
this.currentNode.type = 'SEQUENCE';
this.currentNode.closed = true;
this.state = 'SEQUENCE';
}
// [ starts a section group for this element
if (chr === '[') {
// allowed only for selected elements
if (['BODY', 'BODY.PEEK'].indexOf(this.currentNode.value.toUpperCase()) < 0) {
throw new Error('Unexpected section start char [ at position ' + this.pos);
}
this.currentNode.endPos = this.pos + i;
this.currentNode = this.createNode(this.currentNode.parentNode, this.pos + i);
this.currentNode.type = 'SECTION';
this.currentNode.closed = false;
this.state = 'NORMAL';
break;
}
if (chr === '<') {
throw new Error('Unexpected start of partial at position ' + this.pos);
}
// if the char is not ATOM compatible, throw. Allow \* as an exception
if (imapFormalSyntax['ATOM-CHAR']().indexOf(chr) < 0 && chr !== ']' && !(chr === '*' && this.currentNode.value === '\\')) {
throw new Error('Unexpected char at position ' + (this.pos + i));
} else if (this.currentNode.value === '\\*') {
throw new Error('Unexpected char at position ' + (this.pos + i));
}
this.currentNode.value += chr;
break;
case 'STRING':
// DQUOTE ends the string sequence
if (chr === '"') {
this.currentNode.endPos = this.pos + i;
this.currentNode.closed = true;
this.currentNode = this.currentNode.parentNode;
this.state = 'NORMAL';
checkSP();
break;
}
// \ Escapes the following char
if (chr === '\\') {
i++;
if (i >= len) {
throw new Error('Unexpected end of input at position ' + (this.pos + i));
}
chr = this.str.charAt(i);
}
/* // skip this check, otherwise the parser might explode on binary input
if (imapFormalSyntax['TEXT-CHAR']().indexOf(chr) < 0) {
throw new Error('Unexpected char at position ' + (this.pos + i));
}
*/
this.currentNode.value += chr;
break;
case 'PARTIAL':
if (chr === '>') {
if (this.currentNode.value.substr(-1) === '.') {
throw new Error('Unexpected end of partial at position ' + this.pos);
}
this.currentNode.endPos = this.pos + i;
this.currentNode.closed = true;
this.currentNode = this.currentNode.parentNode;
this.state = 'NORMAL';
checkSP();
break;
}
if (chr === '.' && (!this.currentNode.value.length || this.currentNode.value.match(/\./))) {
throw new Error('Unexpected partial separator . at position ' + this.pos);
}
if (imapFormalSyntax.DIGIT().indexOf(chr) < 0 && chr !== '.') {
throw new Error('Unexpected char at position ' + (this.pos + i));
}
if (this.currentNode.value.match(/^0$|\.0$/) && chr !== '.') {
throw new Error('Invalid partial at position ' + (this.pos + i));
}
this.currentNode.value += chr;
break;
case 'LITERAL':
if (this.currentNode.started) {
//if(imapFormalSyntax['CHAR8']().indexOf(chr) < 0){
if (chr === '\u0000') {
throw new Error('Unexpected \\x00 at position ' + (this.pos + i));
}
this.currentNode.value += chr;
if (this.currentNode.value.length >= this.currentNode.literalLength) {
this.currentNode.endPos = this.pos + i;
this.currentNode.closed = true;
this.currentNode = this.currentNode.parentNode;
this.state = 'NORMAL';
checkSP();
}
break;
}
if (chr === '+' && this.options.literalPlus) {
this.currentNode.literalPlus = true;
break;
}
if (chr === '}') {
if (!('literalLength' in this.currentNode)) {
throw new Error('Unexpected literal prefix end char } at position ' + (this.pos + i));
}
if (this.str.charAt(i + 1) === '\n') {
i++;
} else if (this.str.charAt(i + 1) === '\r' && this.str.charAt(i + 2) === '\n') {
i += 2;
} else {
throw new Error('Unexpected char at position ' + (this.pos + i));
}
this.currentNode.literalLength = Number(this.currentNode.literalLength);
this.currentNode.started = true;
if (!this.currentNode.literalLength) {
// special case where literal content length is 0
// close the node right away, do not wait for additional input
this.currentNode.endPos = this.pos + i;
this.currentNode.closed = true;
this.currentNode = this.currentNode.parentNode;
this.state = 'NORMAL';
checkSP();
}
break;
}
if (imapFormalSyntax.DIGIT().indexOf(chr) < 0) {
throw new Error('Unexpected char at position ' + (this.pos + i));
}
if (this.currentNode.literalLength === '0') {
throw new Error('Invalid literal at position ' + (this.pos + i));
}
this.currentNode.literalLength = (this.currentNode.literalLength || '') + chr;
break;
case 'SEQUENCE':
// space finishes the sequence set
if (chr === ' ') {
if (!this.currentNode.value.substr(-1).match(/\d/) && this.currentNode.value.substr(-1) !== '*') {
throw new Error('Unexpected whitespace at position ' + (this.pos + i));
}
if (this.currentNode.value.substr(-1) === '*' && this.currentNode.value.substr(-2, 1) !== ':') {
throw new Error('Unexpected whitespace at position ' + (this.pos + i));
}
this.currentNode.closed = true;
this.currentNode.endPos = this.pos + i - 1;
this.currentNode = this.currentNode.parentNode;
this.state = 'NORMAL';
break;
} else if (this.currentNode.parentNode &&
chr === ']' &&
this.currentNode.parentNode.type === 'SECTION') {
this.currentNode.endPos = this.pos + i - 1;
this.currentNode = this.currentNode.parentNode;
this.currentNode.closed = true;
this.currentNode.endPos = this.pos + i;
this.currentNode = this.currentNode.parentNode;
this.state = 'NORMAL';
checkSP();
break;
}
if (chr === ':') {
if (!this.currentNode.value.substr(-1).match(/\d/) && this.currentNode.value.substr(-1) !== '*') {
throw new Error('Unexpected range separator : at position ' + (this.pos + i));
}
} else if (chr === '*') {
if ([',', ':'].indexOf(this.currentNode.value.substr(-1)) < 0) {
throw new Error('Unexpected range wildcard at position ' + (this.pos + i));
}
} else if (chr === ',') {
if (!this.currentNode.value.substr(-1).match(/\d/) && this.currentNode.value.substr(-1) !== '*') {
throw new Error('Unexpected sequence separator , at position ' + (this.pos + i));
}
if (this.currentNode.value.substr(-1) === '*' && this.currentNode.value.substr(-2, 1) !== ':') {
throw new Error('Unexpected sequence separator , at position ' + (this.pos + i));
}
} else if (!chr.match(/\d/)) {
throw new Error('Unexpected char at position ' + (this.pos + i));
}
if (chr.match(/\d/) && this.currentNode.value.substr(-1) === '*') {
throw new Error('Unexpected number at position ' + (this.pos + i));
}
this.currentNode.value += chr;
break;
}
}
}
}
class ParserInstance {
constructor(input, options) {
this.input = (input || '').toString();
this.options = options || {};
this.remainder = this.input;
this.pos = 0;
}
getTag() {
if (!this.tag) {
this.tag = this.getElement(imapFormalSyntax.tag() + '*+', true);
}
return this.tag;
}
getCommand() {
let responseCode;
if (!this.command) {
this.command = this.getElement(imapFormalSyntax.command());
}
switch ((this.command || '').toString().toUpperCase()) {
case 'OK':
case 'NO':
case 'BAD':
case 'PREAUTH':
case 'BYE':
responseCode = this.remainder.match(/^ \[(?:[^\]]*\])+/);
if (responseCode) {
this.humanReadable = this.remainder.substr(responseCode[0].length).trim();
this.remainder = responseCode[0];
} else {
this.humanReadable = this.remainder.trim();
this.remainder = '';
}
break;
}
return this.command;
}
getElement(syntax) {
let match, element, errPos;
if (this.remainder.match(/^\s/)) {
throw new Error('Unexpected whitespace at position ' + this.pos);
}
if ((match = this.remainder.match(/^[^\s]+(?=\s|$)/))) {
element = match[0];
if ((errPos = imapFormalSyntax.verify(element, syntax)) >= 0) {
throw new Error('Unexpected char at position ' + (this.pos + errPos));
}
} else {
throw new Error('Unexpected end of input at position ' + this.pos);
}
this.pos += match[0].length;
this.remainder = this.remainder.substr(match[0].length);
return element;
}
getSpace() {
if (!this.remainder.length) {
throw new Error('Unexpected end of input at position ' + this.pos);
}
if (imapFormalSyntax.verify(this.remainder.charAt(0), imapFormalSyntax.SP()) >= 0) {
throw new Error('Unexpected char at position ' + this.pos);
}
this.pos++;
this.remainder = this.remainder.substr(1);
}
getAttributes() {
if (!this.remainder.length) {
throw new Error('Unexpected end of input at position ' + this.pos);
}
if (this.remainder.match(/^\s/)) {
throw new Error('Unexpected whitespace at position ' + this.pos);
}
return new TokenParser(this, this.pos, this.remainder, this.options).getAttributes();
}
}
module.exports = function (command, options) {
let parser, response = {};
options = options || {};
parser = new ParserInstance(command, options);
response.tag = parser.getTag();
parser.getSpace();
response.command = parser.getCommand();
if (['UID', 'AUTHENTICATE'].indexOf((response.command || '').toUpperCase()) >= 0) {
parser.getSpace();
response.command += ' ' + parser.getElement(imapFormalSyntax.command());
}
if (parser.remainder.trim().length) {
parser.getSpace();
response.attributes = parser.getAttributes();
}
if (parser.humanReadable) {
response.attributes = (response.attributes || []).concat({
type: 'TEXT',
value: parser.humanReadable
});
}
return response;
};