serialport-v5
Version:
fork with electron support of Node.js package to access serial ports. Linux, OSX and Windows. Welcome your robotic JavaScript overlords. Better yet, program them!
333 lines (267 loc) • 10.8 kB
JavaScript
var aws4 = exports,
url = require('url'),
querystring = require('querystring'),
crypto = require('crypto'),
lru = require('./lru'),
credentialsCache = lru(1000)
// http://docs.amazonwebservices.com/general/latest/gr/signature-version-4.html
function hmac(key, string, encoding) {
return crypto.createHmac('sha256', key).update(string, 'utf8').digest(encoding)
}
function hash(string, encoding) {
return crypto.createHash('sha256').update(string, 'utf8').digest(encoding)
}
// This function assumes the string has already been percent encoded
function encodeRfc3986(urlEncodedString) {
return urlEncodedString.replace(/[!'()*]/g, function(c) {
return '%' + c.charCodeAt(0).toString(16).toUpperCase()
})
}
// request: { path | body, [host], [method], [headers], [service], [region] }
// credentials: { accessKeyId, secretAccessKey, [sessionToken] }
function RequestSigner(request, credentials) {
if (typeof request === 'string') request = url.parse(request)
var headers = request.headers = (request.headers || {}),
hostParts = this.matchHost(request.hostname || request.host || headers.Host || headers.host)
this.request = request
this.credentials = credentials || this.defaultCredentials()
this.service = request.service || hostParts[0] || ''
this.region = request.region || hostParts[1] || 'us-east-1'
// SES uses a different domain from the service name
if (this.service === 'email') this.service = 'ses'
if (!request.method && request.body)
request.method = 'POST'
if (!headers.Host && !headers.host) {
headers.Host = request.hostname || request.host || this.createHost()
// If a port is specified explicitly, use it as is
if (request.port)
headers.Host += ':' + request.port
}
if (!request.hostname && !request.host)
request.hostname = headers.Host || headers.host
this.isCodeCommitGit = this.service === 'codecommit' && request.method === 'GIT'
}
RequestSigner.prototype.matchHost = function(host) {
var match = (host || '').match(/([^\.]+)\.(?:([^\.]*)\.)?amazonaws\.com$/)
var hostParts = (match || []).slice(1, 3)
// ES's hostParts are sometimes the other way round, if the value that is expected
// to be region equals ‘es’ switch them back
// e.g. search-cluster-name-aaaa00aaaa0aaa0aaaaaaa0aaa.us-east-1.es.amazonaws.com
if (hostParts[1] === 'es')
hostParts = hostParts.reverse()
return hostParts
}
// http://docs.aws.amazon.com/general/latest/gr/rande.html
RequestSigner.prototype.isSingleRegion = function() {
// Special case for S3 and SimpleDB in us-east-1
if (['s3', 'sdb'].indexOf(this.service) >= 0 && this.region === 'us-east-1') return true
return ['cloudfront', 'ls', 'route53', 'iam', 'importexport', 'sts']
.indexOf(this.service) >= 0
}
RequestSigner.prototype.createHost = function() {
var region = this.isSingleRegion() ? '' :
(this.service === 's3' && this.region !== 'us-east-1' ? '-' : '.') + this.region,
service = this.service === 'ses' ? 'email' : this.service
return service + region + '.amazonaws.com'
}
RequestSigner.prototype.prepareRequest = function() {
this.parsePath()
var request = this.request, headers = request.headers, query
if (request.signQuery) {
this.parsedPath.query = query = this.parsedPath.query || {}
if (this.credentials.sessionToken)
query['X-Amz-Security-Token'] = this.credentials.sessionToken
if (this.service === 's3' && !query['X-Amz-Expires'])
query['X-Amz-Expires'] = 86400
if (query['X-Amz-Date'])
this.datetime = query['X-Amz-Date']
else
query['X-Amz-Date'] = this.getDateTime()
query['X-Amz-Algorithm'] = 'AWS4-HMAC-SHA256'
query['X-Amz-Credential'] = this.credentials.accessKeyId + '/' + this.credentialString()
query['X-Amz-SignedHeaders'] = this.signedHeaders()
} else {
if (!request.doNotModifyHeaders && !this.isCodeCommitGit) {
if (request.body && !headers['Content-Type'] && !headers['content-type'])
headers['Content-Type'] = 'application/x-www-form-urlencoded; charset=utf-8'
if (request.body && !headers['Content-Length'] && !headers['content-length'])
headers['Content-Length'] = Buffer.byteLength(request.body)
if (this.credentials.sessionToken && !headers['X-Amz-Security-Token'] && !headers['x-amz-security-token'])
headers['X-Amz-Security-Token'] = this.credentials.sessionToken
if (this.service === 's3' && !headers['X-Amz-Content-Sha256'] && !headers['x-amz-content-sha256'])
headers['X-Amz-Content-Sha256'] = hash(this.request.body || '', 'hex')
if (headers['X-Amz-Date'] || headers['x-amz-date'])
this.datetime = headers['X-Amz-Date'] || headers['x-amz-date']
else
headers['X-Amz-Date'] = this.getDateTime()
}
delete headers.Authorization
delete headers.authorization
}
}
RequestSigner.prototype.sign = function() {
if (!this.parsedPath) this.prepareRequest()
if (this.request.signQuery) {
this.parsedPath.query['X-Amz-Signature'] = this.signature()
} else {
this.request.headers.Authorization = this.authHeader()
}
this.request.path = this.formatPath()
return this.request
}
RequestSigner.prototype.getDateTime = function() {
if (!this.datetime) {
var headers = this.request.headers,
date = new Date(headers.Date || headers.date || new Date)
this.datetime = date.toISOString().replace(/[:\-]|\.\d{3}/g, '')
// Remove the trailing 'Z' on the timestamp string for CodeCommit git access
if (this.isCodeCommitGit) this.datetime = this.datetime.slice(0, -1)
}
return this.datetime
}
RequestSigner.prototype.getDate = function() {
return this.getDateTime().substr(0, 8)
}
RequestSigner.prototype.authHeader = function() {
return [
'AWS4-HMAC-SHA256 Credential=' + this.credentials.accessKeyId + '/' + this.credentialString(),
'SignedHeaders=' + this.signedHeaders(),
'Signature=' + this.signature(),
].join(', ')
}
RequestSigner.prototype.signature = function() {
var date = this.getDate(),
cacheKey = [this.credentials.secretAccessKey, date, this.region, this.service].join(),
kDate, kRegion, kService, kCredentials = credentialsCache.get(cacheKey)
if (!kCredentials) {
kDate = hmac('AWS4' + this.credentials.secretAccessKey, date)
kRegion = hmac(kDate, this.region)
kService = hmac(kRegion, this.service)
kCredentials = hmac(kService, 'aws4_request')
credentialsCache.set(cacheKey, kCredentials)
}
return hmac(kCredentials, this.stringToSign(), 'hex')
}
RequestSigner.prototype.stringToSign = function() {
return [
'AWS4-HMAC-SHA256',
this.getDateTime(),
this.credentialString(),
hash(this.canonicalString(), 'hex'),
].join('\n')
}
RequestSigner.prototype.canonicalString = function() {
if (!this.parsedPath) this.prepareRequest()
var pathStr = this.parsedPath.path,
query = this.parsedPath.query,
headers = this.request.headers,
queryStr = '',
normalizePath = this.service !== 's3',
decodePath = this.service === 's3' || this.request.doNotEncodePath,
decodeSlashesInPath = this.service === 's3',
firstValOnly = this.service === 's3',
bodyHash
if (this.service === 's3' && this.request.signQuery) {
bodyHash = 'UNSIGNED-PAYLOAD'
} else if (this.isCodeCommitGit) {
bodyHash = ''
} else {
bodyHash = headers['X-Amz-Content-Sha256'] || headers['x-amz-content-sha256'] ||
hash(this.request.body || '', 'hex')
}
if (query) {
queryStr = encodeRfc3986(querystring.stringify(Object.keys(query).sort().reduce(function(obj, key) {
if (!key) return obj
obj[key] = !Array.isArray(query[key]) ? query[key] :
(firstValOnly ? query[key][0] : query[key].slice().sort())
return obj
}, {})))
}
if (pathStr !== '/') {
if (normalizePath) pathStr = pathStr.replace(/\/{2,}/g, '/')
pathStr = pathStr.split('/').reduce(function(path, piece) {
if (normalizePath && piece === '..') {
path.pop()
} else if (!normalizePath || piece !== '.') {
if (decodePath) piece = querystring.unescape(piece)
path.push(encodeRfc3986(querystring.escape(piece)))
}
return path
}, []).join('/')
if (pathStr[0] !== '/') pathStr = '/' + pathStr
if (decodeSlashesInPath) pathStr = pathStr.replace(/%2F/g, '/')
}
return [
this.request.method || 'GET',
pathStr,
queryStr,
this.canonicalHeaders() + '\n',
this.signedHeaders(),
bodyHash,
].join('\n')
}
RequestSigner.prototype.canonicalHeaders = function() {
var headers = this.request.headers
function trimAll(header) {
return header.toString().trim().replace(/\s+/g, ' ')
}
return Object.keys(headers)
.sort(function(a, b) { return a.toLowerCase() < b.toLowerCase() ? -1 : 1 })
.map(function(key) { return key.toLowerCase() + ':' + trimAll(headers[key]) })
.join('\n')
}
RequestSigner.prototype.signedHeaders = function() {
return Object.keys(this.request.headers)
.map(function(key) { return key.toLowerCase() })
.sort()
.join(';')
}
RequestSigner.prototype.credentialString = function() {
return [
this.getDate(),
this.region,
this.service,
'aws4_request',
].join('/')
}
RequestSigner.prototype.defaultCredentials = function() {
var env = process.env
return {
accessKeyId: env.AWS_ACCESS_KEY_ID || env.AWS_ACCESS_KEY,
secretAccessKey: env.AWS_SECRET_ACCESS_KEY || env.AWS_SECRET_KEY,
sessionToken: env.AWS_SESSION_TOKEN,
}
}
RequestSigner.prototype.parsePath = function() {
var path = this.request.path || '/',
queryIx = path.indexOf('?'),
query = null
if (queryIx >= 0) {
query = querystring.parse(path.slice(queryIx + 1))
path = path.slice(0, queryIx)
}
// S3 doesn't always encode characters > 127 correctly and
// all services don't encode characters > 255 correctly
// So if there are non-reserved chars (and it's not already all % encoded), just encode them all
if (/[^0-9A-Za-z!'()*\-._~%/]/.test(path)) {
path = path.split('/').map(function(piece) {
return querystring.escape(querystring.unescape(piece))
}).join('/')
}
this.parsedPath = {
path: path,
query: query,
}
}
RequestSigner.prototype.formatPath = function() {
var path = this.parsedPath.path,
query = this.parsedPath.query
if (!query) return path
// Services don't support empty query string keys
if (query[''] != null) delete query['']
return path + '?' + encodeRfc3986(querystring.stringify(query))
}
aws4.RequestSigner = RequestSigner
aws4.sign = function(request, credentials) {
return new RequestSigner(request, credentials).sign()
}