// Copyright 2012 Joyent, Inc. All rights reserved.
|
|
|
|
var assert = require('assert-plus');
|
|
var crypto = require('crypto');
|
|
var http = require('http');
|
|
var util = require('util');
|
|
var sshpk = require('sshpk');
|
|
var jsprim = require('jsprim');
|
|
var utils = require('./utils');
|
|
|
|
var sprintf = require('util').format;
|
|
|
|
var HASH_ALGOS = utils.HASH_ALGOS;
|
|
var PK_ALGOS = utils.PK_ALGOS;
|
|
var InvalidAlgorithmError = utils.InvalidAlgorithmError;
|
|
var HttpSignatureError = utils.HttpSignatureError;
|
|
var validateAlgorithm = utils.validateAlgorithm;
|
|
|
|
///--- Globals
|
|
|
|
var AUTHZ_FMT =
|
|
'Signature keyId="%s",algorithm="%s",headers="%s",signature="%s"';
|
|
|
|
///--- Specific Errors
|
|
|
|
function MissingHeaderError(message) {
|
|
HttpSignatureError.call(this, message, MissingHeaderError);
|
|
}
|
|
util.inherits(MissingHeaderError, HttpSignatureError);
|
|
|
|
function StrictParsingError(message) {
|
|
HttpSignatureError.call(this, message, StrictParsingError);
|
|
}
|
|
util.inherits(StrictParsingError, HttpSignatureError);
|
|
|
|
/* See createSigner() */
|
|
function RequestSigner(options) {
|
|
assert.object(options, 'options');
|
|
|
|
var alg = [];
|
|
if (options.algorithm !== undefined) {
|
|
assert.string(options.algorithm, 'options.algorithm');
|
|
alg = validateAlgorithm(options.algorithm);
|
|
}
|
|
this.rs_alg = alg;
|
|
|
|
/*
|
|
* RequestSigners come in two varieties: ones with an rs_signFunc, and ones
|
|
* with an rs_signer.
|
|
*
|
|
* rs_signFunc-based RequestSigners have to build up their entire signing
|
|
* string within the rs_lines array and give it to rs_signFunc as a single
|
|
* concat'd blob. rs_signer-based RequestSigners can add a line at a time to
|
|
* their signing state by using rs_signer.update(), thus only needing to
|
|
* buffer the hash function state and one line at a time.
|
|
*/
|
|
if (options.sign !== undefined) {
|
|
assert.func(options.sign, 'options.sign');
|
|
this.rs_signFunc = options.sign;
|
|
|
|
} else if (alg[0] === 'hmac' && options.key !== undefined) {
|
|
assert.string(options.keyId, 'options.keyId');
|
|
this.rs_keyId = options.keyId;
|
|
|
|
if (typeof (options.key) !== 'string' && !Buffer.isBuffer(options.key))
|
|
throw (new TypeError('options.key for HMAC must be a string or Buffer'));
|
|
|
|
/*
|
|
* Make an rs_signer for HMACs, not a rs_signFunc -- HMACs digest their
|
|
* data in chunks rather than requiring it all to be given in one go
|
|
* at the end, so they are more similar to signers than signFuncs.
|
|
*/
|
|
this.rs_signer = crypto.createHmac(alg[1].toUpperCase(), options.key);
|
|
this.rs_signer.sign = function () {
|
|
var digest = this.digest('base64');
|
|
return ({
|
|
hashAlgorithm: alg[1],
|
|
toString: function () { return (digest); }
|
|
});
|
|
};
|
|
|
|
} else if (options.key !== undefined) {
|
|
var key = options.key;
|
|
if (typeof (key) === 'string' || Buffer.isBuffer(key))
|
|
key = sshpk.parsePrivateKey(key);
|
|
|
|
assert.ok(sshpk.PrivateKey.isPrivateKey(key, [1, 2]),
|
|
'options.key must be a sshpk.PrivateKey');
|
|
this.rs_key = key;
|
|
|
|
assert.string(options.keyId, 'options.keyId');
|
|
this.rs_keyId = options.keyId;
|
|
|
|
if (!PK_ALGOS[key.type]) {
|
|
throw (new InvalidAlgorithmError(key.type.toUpperCase() + ' type ' +
|
|
'keys are not supported'));
|
|
}
|
|
|
|
if (alg[0] !== undefined && key.type !== alg[0]) {
|
|
throw (new InvalidAlgorithmError('options.key must be a ' +
|
|
alg[0].toUpperCase() + ' key, was given a ' +
|
|
key.type.toUpperCase() + ' key instead'));
|
|
}
|
|
|
|
this.rs_signer = key.createSign(alg[1]);
|
|
|
|
} else {
|
|
throw (new TypeError('options.sign (func) or options.key is required'));
|
|
}
|
|
|
|
this.rs_headers = [];
|
|
this.rs_lines = [];
|
|
}
|
|
|
|
/**
|
|
* Adds a header to be signed, with its value, into this signer.
|
|
*
|
|
* @param {String} header
|
|
* @param {String} value
|
|
* @return {String} value written
|
|
*/
|
|
RequestSigner.prototype.writeHeader = function (header, value) {
|
|
assert.string(header, 'header');
|
|
header = header.toLowerCase();
|
|
assert.string(value, 'value');
|
|
|
|
this.rs_headers.push(header);
|
|
|
|
if (this.rs_signFunc) {
|
|
this.rs_lines.push(header + ': ' + value);
|
|
|
|
} else {
|
|
var line = header + ': ' + value;
|
|
if (this.rs_headers.length > 0)
|
|
line = '\n' + line;
|
|
this.rs_signer.update(line);
|
|
}
|
|
|
|
return (value);
|
|
};
|
|
|
|
/**
|
|
* Adds a default Date header, returning its value.
|
|
*
|
|
* @return {String}
|
|
*/
|
|
RequestSigner.prototype.writeDateHeader = function () {
|
|
return (this.writeHeader('date', jsprim.rfc1123(new Date())));
|
|
};
|
|
|
|
/**
|
|
* Adds the request target line to be signed.
|
|
*
|
|
* @param {String} method, HTTP method (e.g. 'get', 'post', 'put')
|
|
* @param {String} path
|
|
*/
|
|
RequestSigner.prototype.writeTarget = function (method, path) {
|
|
assert.string(method, 'method');
|
|
assert.string(path, 'path');
|
|
method = method.toLowerCase();
|
|
this.writeHeader('(request-target)', method + ' ' + path);
|
|
};
|
|
|
|
/**
|
|
* Calculate the value for the Authorization header on this request
|
|
* asynchronously.
|
|
*
|
|
* @param {Func} callback (err, authz)
|
|
*/
|
|
RequestSigner.prototype.sign = function (cb) {
|
|
assert.func(cb, 'callback');
|
|
|
|
if (this.rs_headers.length < 1)
|
|
throw (new Error('At least one header must be signed'));
|
|
|
|
var alg, authz;
|
|
if (this.rs_signFunc) {
|
|
var data = this.rs_lines.join('\n');
|
|
var self = this;
|
|
this.rs_signFunc(data, function (err, sig) {
|
|
if (err) {
|
|
cb(err);
|
|
return;
|
|
}
|
|
try {
|
|
assert.object(sig, 'signature');
|
|
assert.string(sig.keyId, 'signature.keyId');
|
|
assert.string(sig.algorithm, 'signature.algorithm');
|
|
assert.string(sig.signature, 'signature.signature');
|
|
alg = validateAlgorithm(sig.algorithm);
|
|
|
|
authz = sprintf(AUTHZ_FMT,
|
|
sig.keyId,
|
|
sig.algorithm,
|
|
self.rs_headers.join(' '),
|
|
sig.signature);
|
|
} catch (e) {
|
|
cb(e);
|
|
return;
|
|
}
|
|
cb(null, authz);
|
|
});
|
|
|
|
} else {
|
|
try {
|
|
var sigObj = this.rs_signer.sign();
|
|
} catch (e) {
|
|
cb(e);
|
|
return;
|
|
}
|
|
alg = (this.rs_alg[0] || this.rs_key.type) + '-' + sigObj.hashAlgorithm;
|
|
var signature = sigObj.toString();
|
|
authz = sprintf(AUTHZ_FMT,
|
|
this.rs_keyId,
|
|
alg,
|
|
this.rs_headers.join(' '),
|
|
signature);
|
|
cb(null, authz);
|
|
}
|
|
};
|
|
|
|
///--- Exported API
|
|
|
|
module.exports = {
|
|
/**
|
|
* Identifies whether a given object is a request signer or not.
|
|
*
|
|
* @param {Object} object, the object to identify
|
|
* @returns {Boolean}
|
|
*/
|
|
isSigner: function (obj) {
|
|
if (typeof (obj) === 'object' && obj instanceof RequestSigner)
|
|
return (true);
|
|
return (false);
|
|
},
|
|
|
|
/**
|
|
* Creates a request signer, used to asynchronously build a signature
|
|
* for a request (does not have to be an http.ClientRequest).
|
|
*
|
|
* @param {Object} options, either:
|
|
* - {String} keyId
|
|
* - {String|Buffer} key
|
|
* - {String} algorithm (optional, required for HMAC)
|
|
* or:
|
|
* - {Func} sign (data, cb)
|
|
* @return {RequestSigner}
|
|
*/
|
|
createSigner: function createSigner(options) {
|
|
return (new RequestSigner(options));
|
|
},
|
|
|
|
/**
|
|
* Adds an 'Authorization' header to an http.ClientRequest object.
|
|
*
|
|
* Note that this API will add a Date header if it's not already set. Any
|
|
* other headers in the options.headers array MUST be present, or this
|
|
* will throw.
|
|
*
|
|
* You shouldn't need to check the return type; it's just there if you want
|
|
* to be pedantic.
|
|
*
|
|
* The optional flag indicates whether parsing should use strict enforcement
|
|
* of the version draft-cavage-http-signatures-04 of the spec or beyond.
|
|
* The default is to be loose and support
|
|
* older versions for compatibility.
|
|
*
|
|
* @param {Object} request an instance of http.ClientRequest.
|
|
* @param {Object} options signing parameters object:
|
|
* - {String} keyId required.
|
|
* - {String} key required (either a PEM or HMAC key).
|
|
* - {Array} headers optional; defaults to ['date'].
|
|
* - {String} algorithm optional (unless key is HMAC);
|
|
* default is the same as the sshpk default
|
|
* signing algorithm for the type of key given
|
|
* - {String} httpVersion optional; defaults to '1.1'.
|
|
* - {Boolean} strict optional; defaults to 'false'.
|
|
* @return {Boolean} true if Authorization (and optionally Date) were added.
|
|
* @throws {TypeError} on bad parameter types (input).
|
|
* @throws {InvalidAlgorithmError} if algorithm was bad or incompatible with
|
|
* the given key.
|
|
* @throws {sshpk.KeyParseError} if key was bad.
|
|
* @throws {MissingHeaderError} if a header to be signed was specified but
|
|
* was not present.
|
|
*/
|
|
signRequest: function signRequest(request, options) {
|
|
assert.object(request, 'request');
|
|
assert.object(options, 'options');
|
|
assert.optionalString(options.algorithm, 'options.algorithm');
|
|
assert.string(options.keyId, 'options.keyId');
|
|
assert.optionalArrayOfString(options.headers, 'options.headers');
|
|
assert.optionalString(options.httpVersion, 'options.httpVersion');
|
|
|
|
if (!request.getHeader('Date'))
|
|
request.setHeader('Date', jsprim.rfc1123(new Date()));
|
|
if (!options.headers)
|
|
options.headers = ['date'];
|
|
if (!options.httpVersion)
|
|
options.httpVersion = '1.1';
|
|
|
|
var alg = [];
|
|
if (options.algorithm) {
|
|
options.algorithm = options.algorithm.toLowerCase();
|
|
alg = validateAlgorithm(options.algorithm);
|
|
}
|
|
|
|
var i;
|
|
var stringToSign = '';
|
|
for (i = 0; i < options.headers.length; i++) {
|
|
if (typeof (options.headers[i]) !== 'string')
|
|
throw new TypeError('options.headers must be an array of Strings');
|
|
|
|
var h = options.headers[i].toLowerCase();
|
|
|
|
if (h === 'request-line') {
|
|
if (!options.strict) {
|
|
/**
|
|
* We allow headers from the older spec drafts if strict parsing isn't
|
|
* specified in options.
|
|
*/
|
|
stringToSign +=
|
|
request.method + ' ' + request.path + ' HTTP/' +
|
|
options.httpVersion;
|
|
} else {
|
|
/* Strict parsing doesn't allow older draft headers. */
|
|
throw (new StrictParsingError('request-line is not a valid header ' +
|
|
'with strict parsing enabled.'));
|
|
}
|
|
} else if (h === '(request-target)') {
|
|
stringToSign +=
|
|
'(request-target): ' + request.method.toLowerCase() + ' ' +
|
|
request.path;
|
|
} else {
|
|
var value = request.getHeader(h);
|
|
if (value === undefined || value === '') {
|
|
throw new MissingHeaderError(h + ' was not in the request');
|
|
}
|
|
stringToSign += h + ': ' + value;
|
|
}
|
|
|
|
if ((i + 1) < options.headers.length)
|
|
stringToSign += '\n';
|
|
}
|
|
|
|
/* This is just for unit tests. */
|
|
if (request.hasOwnProperty('_stringToSign')) {
|
|
request._stringToSign = stringToSign;
|
|
}
|
|
|
|
var signature;
|
|
if (alg[0] === 'hmac') {
|
|
if (typeof (options.key) !== 'string' && !Buffer.isBuffer(options.key))
|
|
throw (new TypeError('options.key must be a string or Buffer'));
|
|
|
|
var hmac = crypto.createHmac(alg[1].toUpperCase(), options.key);
|
|
hmac.update(stringToSign);
|
|
signature = hmac.digest('base64');
|
|
|
|
} else {
|
|
var key = options.key;
|
|
if (typeof (key) === 'string' || Buffer.isBuffer(key))
|
|
key = sshpk.parsePrivateKey(options.key);
|
|
|
|
assert.ok(sshpk.PrivateKey.isPrivateKey(key, [1, 2]),
|
|
'options.key must be a sshpk.PrivateKey');
|
|
|
|
if (!PK_ALGOS[key.type]) {
|
|
throw (new InvalidAlgorithmError(key.type.toUpperCase() + ' type ' +
|
|
'keys are not supported'));
|
|
}
|
|
|
|
if (alg[0] !== undefined && key.type !== alg[0]) {
|
|
throw (new InvalidAlgorithmError('options.key must be a ' +
|
|
alg[0].toUpperCase() + ' key, was given a ' +
|
|
key.type.toUpperCase() + ' key instead'));
|
|
}
|
|
|
|
var signer = key.createSign(alg[1]);
|
|
signer.update(stringToSign);
|
|
var sigObj = signer.sign();
|
|
if (!HASH_ALGOS[sigObj.hashAlgorithm]) {
|
|
throw (new InvalidAlgorithmError(sigObj.hashAlgorithm.toUpperCase() +
|
|
' is not a supported hash algorithm'));
|
|
}
|
|
options.algorithm = key.type + '-' + sigObj.hashAlgorithm;
|
|
signature = sigObj.toString();
|
|
assert.notStrictEqual(signature, '', 'empty signature produced');
|
|
}
|
|
|
|
var authzHeaderName = options.authorizationHeaderName || 'Authorization';
|
|
|
|
request.setHeader(authzHeaderName, sprintf(AUTHZ_FMT,
|
|
options.keyId,
|
|
options.algorithm,
|
|
options.headers.join(' '),
|
|
signature));
|
|
|
|
return true;
|
|
}
|
|
|
|
};
|