plugeth/vendor/github.com/Azure/azure-storage-go/authorization.go
Péter Szilágyi c76ad94492 .travis, build: autodelete old unstable archives (#13867)
This commit adds a build step to travis to auto-delete unstable archives older than
14 days (our regular release schedule) from Azure via ci.go purge.

The commit also pulls in the latest Azure storage code, also switching over from
the old import path (github.com/Azure/azure-sdk-for-go) to the new split one
(github.com/Azure/azure-storage-go).
2017-04-06 12:53:33 +02:00

224 lines
5.9 KiB
Go

// Package storage provides clients for Microsoft Azure Storage Services.
package storage
import (
"bytes"
"fmt"
"net/url"
"sort"
"strings"
)
// See: https://docs.microsoft.com/rest/api/storageservices/fileservices/authentication-for-the-azure-storage-services
type authentication string
const (
sharedKey authentication = "sharedKey"
sharedKeyForTable authentication = "sharedKeyTable"
sharedKeyLite authentication = "sharedKeyLite"
sharedKeyLiteForTable authentication = "sharedKeyLiteTable"
// headers
headerAuthorization = "Authorization"
headerContentLength = "Content-Length"
headerDate = "Date"
headerXmsDate = "x-ms-date"
headerXmsVersion = "x-ms-version"
headerContentEncoding = "Content-Encoding"
headerContentLanguage = "Content-Language"
headerContentType = "Content-Type"
headerContentMD5 = "Content-MD5"
headerIfModifiedSince = "If-Modified-Since"
headerIfMatch = "If-Match"
headerIfNoneMatch = "If-None-Match"
headerIfUnmodifiedSince = "If-Unmodified-Since"
headerRange = "Range"
)
func (c *Client) addAuthorizationHeader(verb, url string, headers map[string]string, auth authentication) (map[string]string, error) {
authHeader, err := c.getSharedKey(verb, url, headers, auth)
if err != nil {
return nil, err
}
headers[headerAuthorization] = authHeader
return headers, nil
}
func (c *Client) getSharedKey(verb, url string, headers map[string]string, auth authentication) (string, error) {
canRes, err := c.buildCanonicalizedResource(url, auth)
if err != nil {
return "", err
}
canString, err := buildCanonicalizedString(verb, headers, canRes, auth)
if err != nil {
return "", err
}
return c.createAuthorizationHeader(canString, auth), nil
}
func (c *Client) buildCanonicalizedResource(uri string, auth authentication) (string, error) {
errMsg := "buildCanonicalizedResource error: %s"
u, err := url.Parse(uri)
if err != nil {
return "", fmt.Errorf(errMsg, err.Error())
}
cr := bytes.NewBufferString("/")
cr.WriteString(c.getCanonicalizedAccountName())
if len(u.Path) > 0 {
// Any portion of the CanonicalizedResource string that is derived from
// the resource's URI should be encoded exactly as it is in the URI.
// -- https://msdn.microsoft.com/en-gb/library/azure/dd179428.aspx
cr.WriteString(u.EscapedPath())
}
params, err := url.ParseQuery(u.RawQuery)
if err != nil {
return "", fmt.Errorf(errMsg, err.Error())
}
// See https://github.com/Azure/azure-storage-net/blob/master/Lib/Common/Core/Util/AuthenticationUtility.cs#L277
if auth == sharedKey {
if len(params) > 0 {
cr.WriteString("\n")
keys := []string{}
for key := range params {
keys = append(keys, key)
}
sort.Strings(keys)
completeParams := []string{}
for _, key := range keys {
if len(params[key]) > 1 {
sort.Strings(params[key])
}
completeParams = append(completeParams, fmt.Sprintf("%s:%s", key, strings.Join(params[key], ",")))
}
cr.WriteString(strings.Join(completeParams, "\n"))
}
} else {
// search for "comp" parameter, if exists then add it to canonicalizedresource
if v, ok := params["comp"]; ok {
cr.WriteString("?comp=" + v[0])
}
}
return string(cr.Bytes()), nil
}
func (c *Client) getCanonicalizedAccountName() string {
// since we may be trying to access a secondary storage account, we need to
// remove the -secondary part of the storage name
return strings.TrimSuffix(c.accountName, "-secondary")
}
func buildCanonicalizedString(verb string, headers map[string]string, canonicalizedResource string, auth authentication) (string, error) {
contentLength := headers[headerContentLength]
if contentLength == "0" {
contentLength = ""
}
date := headers[headerDate]
if v, ok := headers[headerXmsDate]; ok {
if auth == sharedKey || auth == sharedKeyLite {
date = ""
} else {
date = v
}
}
var canString string
switch auth {
case sharedKey:
canString = strings.Join([]string{
verb,
headers[headerContentEncoding],
headers[headerContentLanguage],
contentLength,
headers[headerContentMD5],
headers[headerContentType],
date,
headers[headerIfModifiedSince],
headers[headerIfMatch],
headers[headerIfNoneMatch],
headers[headerIfUnmodifiedSince],
headers[headerRange],
buildCanonicalizedHeader(headers),
canonicalizedResource,
}, "\n")
case sharedKeyForTable:
canString = strings.Join([]string{
verb,
headers[headerContentMD5],
headers[headerContentType],
date,
canonicalizedResource,
}, "\n")
case sharedKeyLite:
canString = strings.Join([]string{
verb,
headers[headerContentMD5],
headers[headerContentType],
date,
buildCanonicalizedHeader(headers),
canonicalizedResource,
}, "\n")
case sharedKeyLiteForTable:
canString = strings.Join([]string{
date,
canonicalizedResource,
}, "\n")
default:
return "", fmt.Errorf("%s authentication is not supported yet", auth)
}
return canString, nil
}
func buildCanonicalizedHeader(headers map[string]string) string {
cm := make(map[string]string)
for k, v := range headers {
headerName := strings.TrimSpace(strings.ToLower(k))
if strings.HasPrefix(headerName, "x-ms-") {
cm[headerName] = v
}
}
if len(cm) == 0 {
return ""
}
keys := []string{}
for key := range cm {
keys = append(keys, key)
}
sort.Strings(keys)
ch := bytes.NewBufferString("")
for _, key := range keys {
ch.WriteString(key)
ch.WriteRune(':')
ch.WriteString(cm[key])
ch.WriteRune('\n')
}
return strings.TrimSuffix(string(ch.Bytes()), "\n")
}
func (c *Client) createAuthorizationHeader(canonicalizedString string, auth authentication) string {
signature := c.computeHmac256(canonicalizedString)
var key string
switch auth {
case sharedKey, sharedKeyForTable:
key = "SharedKey"
case sharedKeyLite, sharedKeyLiteForTable:
key = "SharedKeyLite"
}
return fmt.Sprintf("%s %s:%s", key, c.getCanonicalizedAccountName(), signature)
}