vendor: github.com/abbot/go-http-auth for #1802

vendor/github.com/abbot/go-http-auth/misc.go

@@ -0,0 +1,141 @@
+package auth
+
+import (
+	"bytes"
+	"crypto/md5"
+	"crypto/rand"
+	"encoding/base64"
+	"fmt"
+	"net/http"
+	"strings"
+)
+
+// RandomKey returns a random 16-byte base64 alphabet string
+func RandomKey() string {
+	k := make([]byte, 12)
+	for bytes := 0; bytes < len(k); {
+		n, err := rand.Read(k[bytes:])
+		if err != nil {
+			panic("rand.Read() failed")
+		}
+		bytes += n
+	}
+	return base64.StdEncoding.EncodeToString(k)
+}
+
+// H function for MD5 algorithm (returns a lower-case hex MD5 digest)
+func H(data string) string {
+	digest := md5.New()
+	digest.Write([]byte(data))
+	return fmt.Sprintf("%x", digest.Sum(nil))
+}
+
+// ParseList parses a comma-separated list of values as described by
+// RFC 2068 and returns list elements.
+//
+// Lifted from https://code.google.com/p/gorilla/source/browse/http/parser/parser.go
+// which was ported from urllib2.parse_http_list, from the Python
+// standard library.
+func ParseList(value string) []string {
+	var list []string
+	var escape, quote bool
+	b := new(bytes.Buffer)
+	for _, r := range value {
+		switch {
+		case escape:
+			b.WriteRune(r)
+			escape = false
+		case quote:
+			if r == '\\' {
+				escape = true
+			} else {
+				if r == '"' {
+					quote = false
+				}
+				b.WriteRune(r)
+			}
+		case r == ',':
+			list = append(list, strings.TrimSpace(b.String()))
+			b.Reset()
+		case r == '"':
+			quote = true
+			b.WriteRune(r)
+		default:
+			b.WriteRune(r)
+		}
+	}
+	// Append last part.
+	if s := b.String(); s != "" {
+		list = append(list, strings.TrimSpace(s))
+	}
+	return list
+}
+
+// ParsePairs extracts key/value pairs from a comma-separated list of
+// values as described by RFC 2068 and returns a map[key]value. The
+// resulting values are unquoted. If a list element doesn't contain a
+// "=", the key is the element itself and the value is an empty
+// string.
+//
+// Lifted from https://code.google.com/p/gorilla/source/browse/http/parser/parser.go
+func ParsePairs(value string) map[string]string {
+	m := make(map[string]string)
+	for _, pair := range ParseList(strings.TrimSpace(value)) {
+		if i := strings.Index(pair, "="); i < 0 {
+			m[pair] = ""
+		} else {
+			v := pair[i+1:]
+			if v[0] == '"' && v[len(v)-1] == '"' {
+				// Unquote it.
+				v = v[1 : len(v)-1]
+			}
+			m[pair[:i]] = v
+		}
+	}
+	return m
+}
+
+// Headers contains header and error codes used by authenticator.
+type Headers struct {
+	Authenticate      string // WWW-Authenticate
+	Authorization     string // Authorization
+	AuthInfo          string // Authentication-Info
+	UnauthCode        int    // 401
+	UnauthContentType string // text/plain
+	UnauthResponse    string // Unauthorized.
+}
+
+// V returns NormalHeaders when h is nil, or h otherwise. Allows to
+// use uninitialized *Headers values in structs.
+func (h *Headers) V() *Headers {
+	if h == nil {
+		return NormalHeaders
+	}
+	return h
+}
+
+var (
+	// NormalHeaders are the regular Headers used by an HTTP Server for
+	// request authentication.
+	NormalHeaders = &Headers{
+		Authenticate:      "WWW-Authenticate",
+		Authorization:     "Authorization",
+		AuthInfo:          "Authentication-Info",
+		UnauthCode:        http.StatusUnauthorized,
+		UnauthContentType: "text/plain",
+		UnauthResponse:    fmt.Sprintf("%d %s\n", http.StatusUnauthorized, http.StatusText(http.StatusUnauthorized)),
+	}
+
+	// ProxyHeaders are Headers used by an HTTP Proxy server for proxy
+	// access authentication.
+	ProxyHeaders = &Headers{
+		Authenticate:      "Proxy-Authenticate",
+		Authorization:     "Proxy-Authorization",
+		AuthInfo:          "Proxy-Authentication-Info",
+		UnauthCode:        http.StatusProxyAuthRequired,
+		UnauthContentType: "text/plain",
+		UnauthResponse:    fmt.Sprintf("%d %s\n", http.StatusProxyAuthRequired, http.StatusText(http.StatusProxyAuthRequired)),
+	}
+)
+
+const contentType = "Content-Type"