Vendor main dependencies.

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

@@ -0,0 +1,178 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
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+      and distribution as defined by Sections 1 through 9 of this document.
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+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
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+
+   END OF TERMS AND CONDITIONS
+

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

@@ -0,0 +1,109 @@
+// Package auth is an implementation of HTTP Basic and HTTP Digest authentication.
+package auth
+
+import (
+	"net/http"
+
+	"golang.org/x/net/context"
+)
+
+/*
+ Request handlers must take AuthenticatedRequest instead of http.Request
+*/
+type AuthenticatedRequest struct {
+	http.Request
+	/*
+	 Authenticated user name. Current API implies that Username is
+	 never empty, which means that authentication is always done
+	 before calling the request handler.
+	*/
+	Username string
+}
+
+/*
+ AuthenticatedHandlerFunc is like http.HandlerFunc, but takes
+ AuthenticatedRequest instead of http.Request
+*/
+type AuthenticatedHandlerFunc func(http.ResponseWriter, *AuthenticatedRequest)
+
+/*
+ Authenticator wraps an AuthenticatedHandlerFunc with
+ authentication-checking code.
+
+ Typical Authenticator usage is something like:
+
+   authenticator := SomeAuthenticator(...)
+   http.HandleFunc("/", authenticator(my_handler))
+
+ Authenticator wrapper checks the user authentication and calls the
+ wrapped function only after authentication has succeeded. Otherwise,
+ it returns a handler which initiates the authentication procedure.
+*/
+type Authenticator func(AuthenticatedHandlerFunc) http.HandlerFunc
+
+// Info contains authentication information for the request.
+type Info struct {
+	// Authenticated is set to true when request was authenticated
+	// successfully, i.e. username and password passed in request did
+	// pass the check.
+	Authenticated bool
+
+	// Username contains a user name passed in the request when
+	// Authenticated is true. It's value is undefined if Authenticated
+	// is false.
+	Username string
+
+	// ResponseHeaders contains extra headers that must be set by server
+	// when sending back HTTP response.
+	ResponseHeaders http.Header
+}
+
+// UpdateHeaders updates headers with this Info's ResponseHeaders. It is
+// safe to call this function on nil Info.
+func (i *Info) UpdateHeaders(headers http.Header) {
+	if i == nil {
+		return
+	}
+	for k, values := range i.ResponseHeaders {
+		for _, v := range values {
+			headers.Add(k, v)
+		}
+	}
+}
+
+type key int // used for context keys
+
+var infoKey key = 0
+
+type AuthenticatorInterface interface {
+	// NewContext returns a new context carrying authentication
+	// information extracted from the request.
+	NewContext(ctx context.Context, r *http.Request) context.Context
+
+	// Wrap returns an http.HandlerFunc which wraps
+	// AuthenticatedHandlerFunc with this authenticator's
+	// authentication checks.
+	Wrap(AuthenticatedHandlerFunc) http.HandlerFunc
+}
+
+// FromContext returns authentication information from the context or
+// nil if no such information present.
+func FromContext(ctx context.Context) *Info {
+	info, ok := ctx.Value(infoKey).(*Info)
+	if !ok {
+		return nil
+	}
+	return info
+}
+
+// AuthUsernameHeader is the header set by JustCheck functions. It
+// contains an authenticated username (if authentication was
+// successful).
+const AuthUsernameHeader = "X-Authenticated-Username"
+
+func JustCheck(auth AuthenticatorInterface, wrapped http.HandlerFunc) http.HandlerFunc {
+	return auth.Wrap(func(w http.ResponseWriter, ar *AuthenticatedRequest) {
+		ar.Header.Set(AuthUsernameHeader, ar.Username)
+		wrapped(w, &ar.Request)
+	})
+}

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

@@ -0,0 +1,163 @@
+package auth
+
+import (
+	"bytes"
+	"crypto/sha1"
+	"crypto/subtle"
+	"encoding/base64"
+	"errors"
+	"net/http"
+	"strings"
+
+	"golang.org/x/crypto/bcrypt"
+	"golang.org/x/net/context"
+)
+
+type compareFunc func(hashedPassword, password []byte) error
+
+var (
+	errMismatchedHashAndPassword = errors.New("mismatched hash and password")
+
+	compareFuncs = []struct {
+		prefix  string
+		compare compareFunc
+	}{
+		{"", compareMD5HashAndPassword}, // default compareFunc
+		{"{SHA}", compareShaHashAndPassword},
+		// Bcrypt is complicated. According to crypt(3) from
+		// crypt_blowfish version 1.3 (fetched from
+		// http://www.openwall.com/crypt/crypt_blowfish-1.3.tar.gz), there
+		// are three different has prefixes: "$2a$", used by versions up
+		// to 1.0.4, and "$2x$" and "$2y$", used in all later
+		// versions. "$2a$" has a known bug, "$2x$" was added as a
+		// migration path for systems with "$2a$" prefix and still has a
+		// bug, and only "$2y$" should be used by modern systems. The bug
+		// has something to do with handling of 8-bit characters. Since
+		// both "$2a$" and "$2x$" are deprecated, we are handling them the
+		// same way as "$2y$", which will yield correct results for 7-bit
+		// character passwords, but is wrong for 8-bit character
+		// passwords. You have to upgrade to "$2y$" if you want sant 8-bit
+		// character password support with bcrypt. To add to the mess,
+		// OpenBSD 5.5. introduced "$2b$" prefix, which behaves exactly
+		// like "$2y$" according to the same source.
+		{"$2a$", bcrypt.CompareHashAndPassword},
+		{"$2b$", bcrypt.CompareHashAndPassword},
+		{"$2x$", bcrypt.CompareHashAndPassword},
+		{"$2y$", bcrypt.CompareHashAndPassword},
+	}
+)
+
+type BasicAuth struct {
+	Realm   string
+	Secrets SecretProvider
+	// Headers used by authenticator. Set to ProxyHeaders to use with
+	// proxy server. When nil, NormalHeaders are used.
+	Headers *Headers
+}
+
+// check that BasicAuth implements AuthenticatorInterface
+var _ = (AuthenticatorInterface)((*BasicAuth)(nil))
+
+/*
+ Checks the username/password combination from the request. Returns
+ either an empty string (authentication failed) or the name of the
+ authenticated user.
+
+ Supports MD5 and SHA1 password entries
+*/
+func (a *BasicAuth) CheckAuth(r *http.Request) string {
+	s := strings.SplitN(r.Header.Get(a.Headers.V().Authorization), " ", 2)
+	if len(s) != 2 || s[0] != "Basic" {
+		return ""
+	}
+
+	b, err := base64.StdEncoding.DecodeString(s[1])
+	if err != nil {
+		return ""
+	}
+	pair := strings.SplitN(string(b), ":", 2)
+	if len(pair) != 2 {
+		return ""
+	}
+	user, password := pair[0], pair[1]
+	secret := a.Secrets(user, a.Realm)
+	if secret == "" {
+		return ""
+	}
+	compare := compareFuncs[0].compare
+	for _, cmp := range compareFuncs[1:] {
+		if strings.HasPrefix(secret, cmp.prefix) {
+			compare = cmp.compare
+			break
+		}
+	}
+	if compare([]byte(secret), []byte(password)) != nil {
+		return ""
+	}
+	return pair[0]
+}
+
+func compareShaHashAndPassword(hashedPassword, password []byte) error {
+	d := sha1.New()
+	d.Write(password)
+	if subtle.ConstantTimeCompare(hashedPassword[5:], []byte(base64.StdEncoding.EncodeToString(d.Sum(nil)))) != 1 {
+		return errMismatchedHashAndPassword
+	}
+	return nil
+}
+
+func compareMD5HashAndPassword(hashedPassword, password []byte) error {
+	parts := bytes.SplitN(hashedPassword, []byte("$"), 4)
+	if len(parts) != 4 {
+		return errMismatchedHashAndPassword
+	}
+	magic := []byte("$" + string(parts[1]) + "$")
+	salt := parts[2]
+	if subtle.ConstantTimeCompare(hashedPassword, MD5Crypt(password, salt, magic)) != 1 {
+		return errMismatchedHashAndPassword
+	}
+	return nil
+}
+
+/*
+ http.Handler for BasicAuth which initiates the authentication process
+ (or requires reauthentication).
+*/
+func (a *BasicAuth) RequireAuth(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set(contentType, a.Headers.V().UnauthContentType)
+	w.Header().Set(a.Headers.V().Authenticate, `Basic realm="`+a.Realm+`"`)
+	w.WriteHeader(a.Headers.V().UnauthCode)
+	w.Write([]byte(a.Headers.V().UnauthResponse))
+}
+
+/*
+ BasicAuthenticator returns a function, which wraps an
+ AuthenticatedHandlerFunc converting it to http.HandlerFunc. This
+ wrapper function checks the authentication and either sends back
+ required authentication headers, or calls the wrapped function with
+ authenticated username in the AuthenticatedRequest.
+*/
+func (a *BasicAuth) Wrap(wrapped AuthenticatedHandlerFunc) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if username := a.CheckAuth(r); username == "" {
+			a.RequireAuth(w, r)
+		} else {
+			ar := &AuthenticatedRequest{Request: *r, Username: username}
+			wrapped(w, ar)
+		}
+	}
+}
+
+// NewContext returns a context carrying authentication information for the request.
+func (a *BasicAuth) NewContext(ctx context.Context, r *http.Request) context.Context {
+	info := &Info{Username: a.CheckAuth(r), ResponseHeaders: make(http.Header)}
+	info.Authenticated = (info.Username != "")
+	if !info.Authenticated {
+		info.ResponseHeaders.Set(a.Headers.V().Authenticate, `Basic realm="`+a.Realm+`"`)
+	}
+	return context.WithValue(ctx, infoKey, info)
+}
+
+func NewBasicAuthenticator(realm string, secrets SecretProvider) *BasicAuth {
+	return &BasicAuth{Realm: realm, Secrets: secrets}
+}

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

@@ -0,0 +1,274 @@
+package auth
+
+import (
+	"crypto/subtle"
+	"fmt"
+	"net/http"
+	"net/url"
+	"sort"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"golang.org/x/net/context"
+)
+
+type digest_client struct {
+	nc        uint64
+	last_seen int64
+}
+
+type DigestAuth struct {
+	Realm            string
+	Opaque           string
+	Secrets          SecretProvider
+	PlainTextSecrets bool
+	IgnoreNonceCount bool
+	// Headers used by authenticator. Set to ProxyHeaders to use with
+	// proxy server. When nil, NormalHeaders are used.
+	Headers *Headers
+
+	/*
+	   Approximate size of Client's Cache. When actual number of
+	   tracked client nonces exceeds
+	   ClientCacheSize+ClientCacheTolerance, ClientCacheTolerance*2
+	   older entries are purged.
+	*/
+	ClientCacheSize      int
+	ClientCacheTolerance int
+
+	clients map[string]*digest_client
+	mutex   sync.Mutex
+}
+
+// check that DigestAuth implements AuthenticatorInterface
+var _ = (AuthenticatorInterface)((*DigestAuth)(nil))
+
+type digest_cache_entry struct {
+	nonce     string
+	last_seen int64
+}
+
+type digest_cache []digest_cache_entry
+
+func (c digest_cache) Less(i, j int) bool {
+	return c[i].last_seen < c[j].last_seen
+}
+
+func (c digest_cache) Len() int {
+	return len(c)
+}
+
+func (c digest_cache) Swap(i, j int) {
+	c[i], c[j] = c[j], c[i]
+}
+
+/*
+ Remove count oldest entries from DigestAuth.clients
+*/
+func (a *DigestAuth) Purge(count int) {
+	entries := make([]digest_cache_entry, 0, len(a.clients))
+	for nonce, client := range a.clients {
+		entries = append(entries, digest_cache_entry{nonce, client.last_seen})
+	}
+	cache := digest_cache(entries)
+	sort.Sort(cache)
+	for _, client := range cache[:count] {
+		delete(a.clients, client.nonce)
+	}
+}
+
+/*
+ http.Handler for DigestAuth which initiates the authentication process
+ (or requires reauthentication).
+*/
+func (a *DigestAuth) RequireAuth(w http.ResponseWriter, r *http.Request) {
+	if len(a.clients) > a.ClientCacheSize+a.ClientCacheTolerance {
+		a.Purge(a.ClientCacheTolerance * 2)
+	}
+	nonce := RandomKey()
+	a.clients[nonce] = &digest_client{nc: 0, last_seen: time.Now().UnixNano()}
+	w.Header().Set(contentType, a.Headers.V().UnauthContentType)
+	w.Header().Set(a.Headers.V().Authenticate,
+		fmt.Sprintf(`Digest realm="%s", nonce="%s", opaque="%s", algorithm="MD5", qop="auth"`,
+			a.Realm, nonce, a.Opaque))
+	w.WriteHeader(a.Headers.V().UnauthCode)
+	w.Write([]byte(a.Headers.V().UnauthResponse))
+}
+
+/*
+ Parse Authorization header from the http.Request. Returns a map of
+ auth parameters or nil if the header is not a valid parsable Digest
+ auth header.
+*/
+func DigestAuthParams(authorization string) map[string]string {
+	s := strings.SplitN(authorization, " ", 2)
+	if len(s) != 2 || s[0] != "Digest" {
+		return nil
+	}
+
+	return ParsePairs(s[1])
+}
+
+/*
+ Check if request contains valid authentication data. Returns a pair
+ of username, authinfo where username is the name of the authenticated
+ user or an empty string and authinfo is the contents for the optional
+ Authentication-Info response header.
+*/
+func (da *DigestAuth) CheckAuth(r *http.Request) (username string, authinfo *string) {
+	da.mutex.Lock()
+	defer da.mutex.Unlock()
+	username = ""
+	authinfo = nil
+	auth := DigestAuthParams(r.Header.Get(da.Headers.V().Authorization))
+	if auth == nil {
+		return "", nil
+	}
+	// RFC2617 Section 3.2.1 specifies that unset value of algorithm in
+	// WWW-Authenticate Response header should be treated as
+	// "MD5". According to section 3.2.2 the "algorithm" value in
+	// subsequent Request Authorization header must be set to whatever
+	// was supplied in the WWW-Authenticate Response header. This
+	// implementation always returns an algorithm in WWW-Authenticate
+	// header, however there seems to be broken clients in the wild
+	// which do not set the algorithm. Assume the unset algorithm in
+	// Authorization header to be equal to MD5.
+	if _, ok := auth["algorithm"]; !ok {
+		auth["algorithm"] = "MD5"
+	}
+	if da.Opaque != auth["opaque"] || auth["algorithm"] != "MD5" || auth["qop"] != "auth" {
+		return "", nil
+	}
+
+	// Check if the requested URI matches auth header
+	if r.RequestURI != auth["uri"] {
+		// We allow auth["uri"] to be a full path prefix of request-uri
+		// for some reason lost in history, which is probably wrong, but
+		// used to be like that for quite some time
+		// (https://tools.ietf.org/html/rfc2617#section-3.2.2 explicitly
+		// says that auth["uri"] is the request-uri).
+		//
+		// TODO: make an option to allow only strict checking.
+		switch u, err := url.Parse(auth["uri"]); {
+		case err != nil:
+			return "", nil
+		case r.URL == nil:
+			return "", nil
+		case len(u.Path) > len(r.URL.Path):
+			return "", nil
+		case !strings.HasPrefix(r.URL.Path, u.Path):
+			return "", nil
+		}
+	}
+
+	HA1 := da.Secrets(auth["username"], da.Realm)
+	if da.PlainTextSecrets {
+		HA1 = H(auth["username"] + ":" + da.Realm + ":" + HA1)
+	}
+	HA2 := H(r.Method + ":" + auth["uri"])
+	KD := H(strings.Join([]string{HA1, auth["nonce"], auth["nc"], auth["cnonce"], auth["qop"], HA2}, ":"))
+
+	if subtle.ConstantTimeCompare([]byte(KD), []byte(auth["response"])) != 1 {
+		return "", nil
+	}
+
+	// At this point crypto checks are completed and validated.
+	// Now check if the session is valid.
+
+	nc, err := strconv.ParseUint(auth["nc"], 16, 64)
+	if err != nil {
+		return "", nil
+	}
+
+	if client, ok := da.clients[auth["nonce"]]; !ok {
+		return "", nil
+	} else {
+		if client.nc != 0 && client.nc >= nc && !da.IgnoreNonceCount {
+			return "", nil
+		}
+		client.nc = nc
+		client.last_seen = time.Now().UnixNano()
+	}
+
+	resp_HA2 := H(":" + auth["uri"])
+	rspauth := H(strings.Join([]string{HA1, auth["nonce"], auth["nc"], auth["cnonce"], auth["qop"], resp_HA2}, ":"))
+
+	info := fmt.Sprintf(`qop="auth", rspauth="%s", cnonce="%s", nc="%s"`, rspauth, auth["cnonce"], auth["nc"])
+	return auth["username"], &info
+}
+
+/*
+ Default values for ClientCacheSize and ClientCacheTolerance for DigestAuth
+*/
+const DefaultClientCacheSize = 1000
+const DefaultClientCacheTolerance = 100
+
+/*
+ Wrap returns an Authenticator which uses HTTP Digest
+ authentication. Arguments:
+
+ realm: The authentication realm.
+
+ secrets: SecretProvider which must return HA1 digests for the same
+ realm as above.
+*/
+func (a *DigestAuth) Wrap(wrapped AuthenticatedHandlerFunc) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if username, authinfo := a.CheckAuth(r); username == "" {
+			a.RequireAuth(w, r)
+		} else {
+			ar := &AuthenticatedRequest{Request: *r, Username: username}
+			if authinfo != nil {
+				w.Header().Set(a.Headers.V().AuthInfo, *authinfo)
+			}
+			wrapped(w, ar)
+		}
+	}
+}
+
+/*
+ JustCheck returns function which converts an http.HandlerFunc into a
+ http.HandlerFunc which requires authentication. Username is passed as
+ an extra X-Authenticated-Username header.
+*/
+func (a *DigestAuth) JustCheck(wrapped http.HandlerFunc) http.HandlerFunc {
+	return a.Wrap(func(w http.ResponseWriter, ar *AuthenticatedRequest) {
+		ar.Header.Set(AuthUsernameHeader, ar.Username)
+		wrapped(w, &ar.Request)
+	})
+}
+
+// NewContext returns a context carrying authentication information for the request.
+func (a *DigestAuth) NewContext(ctx context.Context, r *http.Request) context.Context {
+	username, authinfo := a.CheckAuth(r)
+	info := &Info{Username: username, ResponseHeaders: make(http.Header)}
+	if username != "" {
+		info.Authenticated = true
+		info.ResponseHeaders.Set(a.Headers.V().AuthInfo, *authinfo)
+	} else {
+		// return back digest WWW-Authenticate header
+		if len(a.clients) > a.ClientCacheSize+a.ClientCacheTolerance {
+			a.Purge(a.ClientCacheTolerance * 2)
+		}
+		nonce := RandomKey()
+		a.clients[nonce] = &digest_client{nc: 0, last_seen: time.Now().UnixNano()}
+		info.ResponseHeaders.Set(a.Headers.V().Authenticate,
+			fmt.Sprintf(`Digest realm="%s", nonce="%s", opaque="%s", algorithm="MD5", qop="auth"`,
+				a.Realm, nonce, a.Opaque))
+	}
+	return context.WithValue(ctx, infoKey, info)
+}
+
+func NewDigestAuthenticator(realm string, secrets SecretProvider) *DigestAuth {
+	da := &DigestAuth{
+		Opaque:               RandomKey(),
+		Realm:                realm,
+		Secrets:              secrets,
+		PlainTextSecrets:     false,
+		ClientCacheSize:      DefaultClientCacheSize,
+		ClientCacheTolerance: DefaultClientCacheTolerance,
+		clients:              map[string]*digest_client{}}
+	return da
+}

vendor/github.com/abbot/go-http-auth/md5crypt.go

@@ -0,0 +1,92 @@
+package auth
+
+import "crypto/md5"
+import "strings"
+
+const itoa64 = "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
+
+var md5_crypt_swaps = [16]int{12, 6, 0, 13, 7, 1, 14, 8, 2, 15, 9, 3, 5, 10, 4, 11}
+
+type MD5Entry struct {
+	Magic, Salt, Hash []byte
+}
+
+func NewMD5Entry(e string) *MD5Entry {
+	parts := strings.SplitN(e, "$", 4)
+	if len(parts) != 4 {
+		return nil
+	}
+	return &MD5Entry{
+		Magic: []byte("$" + parts[1] + "$"),
+		Salt:  []byte(parts[2]),
+		Hash:  []byte(parts[3]),
+	}
+}
+
+/*
+ MD5 password crypt implementation
+*/
+func MD5Crypt(password, salt, magic []byte) []byte {
+	d := md5.New()
+
+	d.Write(password)
+	d.Write(magic)
+	d.Write(salt)
+
+	d2 := md5.New()
+	d2.Write(password)
+	d2.Write(salt)
+	d2.Write(password)
+
+	for i, mixin := 0, d2.Sum(nil); i < len(password); i++ {
+		d.Write([]byte{mixin[i%16]})
+	}
+
+	for i := len(password); i != 0; i >>= 1 {
+		if i&1 == 0 {
+			d.Write([]byte{password[0]})
+		} else {
+			d.Write([]byte{0})
+		}
+	}
+
+	final := d.Sum(nil)
+
+	for i := 0; i < 1000; i++ {
+		d2 := md5.New()
+		if i&1 == 0 {
+			d2.Write(final)
+		} else {
+			d2.Write(password)
+		}
+
+		if i%3 != 0 {
+			d2.Write(salt)
+		}
+
+		if i%7 != 0 {
+			d2.Write(password)
+		}
+
+		if i&1 == 0 {
+			d2.Write(password)
+		} else {
+			d2.Write(final)
+		}
+		final = d2.Sum(nil)
+	}
+
+	result := make([]byte, 0, 22)
+	v := uint(0)
+	bits := uint(0)
+	for _, i := range md5_crypt_swaps {
+		v |= (uint(final[i]) << bits)
+		for bits = bits + 8; bits > 6; bits -= 6 {
+			result = append(result, itoa64[v&0x3f])
+			v >>= 6
+		}
+	}
+	result = append(result, itoa64[v&0x3f])
+
+	return append(append(append(magic, salt...), '$'), result...)
+}

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"

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

@@ -0,0 +1,138 @@
+package auth
+
+import "encoding/csv"
+import "os"
+
+/* 
+ SecretProvider is used by authenticators. Takes user name and realm
+ as an argument, returns secret required for authentication (HA1 for
+ digest authentication, properly encrypted password for basic).
+ 
+ Returning an empty string means failing the authentication.
+*/
+type SecretProvider func(user, realm string) string
+
+/*
+ Common functions for file auto-reloading
+*/
+type File struct {
+	Path string
+	Info os.FileInfo
+	/* must be set in inherited types during initialization */
+	Reload func()
+}
+
+func (f *File) ReloadIfNeeded() {
+	info, err := os.Stat(f.Path)
+	if err != nil {
+		panic(err)
+	}
+	if f.Info == nil || f.Info.ModTime() != info.ModTime() {
+		f.Info = info
+		f.Reload()
+	}
+}
+
+/*
+ Structure used for htdigest file authentication. Users map realms to
+ maps of users to their HA1 digests.
+*/
+type HtdigestFile struct {
+	File
+	Users map[string]map[string]string
+}
+
+func reload_htdigest(hf *HtdigestFile) {
+	r, err := os.Open(hf.Path)
+	if err != nil {
+		panic(err)
+	}
+	csv_reader := csv.NewReader(r)
+	csv_reader.Comma = ':'
+	csv_reader.Comment = '#'
+	csv_reader.TrimLeadingSpace = true
+
+	records, err := csv_reader.ReadAll()
+	if err != nil {
+		panic(err)
+	}
+
+	hf.Users = make(map[string]map[string]string)
+	for _, record := range records {
+		_, exists := hf.Users[record[1]]
+		if !exists {
+			hf.Users[record[1]] = make(map[string]string)
+		}
+		hf.Users[record[1]][record[0]] = record[2]
+	}
+}
+
+/*
+ SecretProvider implementation based on htdigest-formated files. Will
+ reload htdigest file on changes. Will panic on syntax errors in
+ htdigest files.
+*/
+func HtdigestFileProvider(filename string) SecretProvider {
+	hf := &HtdigestFile{File: File{Path: filename}}
+	hf.Reload = func() { reload_htdigest(hf) }
+	return func(user, realm string) string {
+		hf.ReloadIfNeeded()
+		_, exists := hf.Users[realm]
+		if !exists {
+			return ""
+		}
+		digest, exists := hf.Users[realm][user]
+		if !exists {
+			return ""
+		}
+		return digest
+	}
+}
+
+/*
+ Structure used for htdigest file authentication. Users map users to
+ their salted encrypted password
+*/
+type HtpasswdFile struct {
+	File
+	Users map[string]string
+}
+
+func reload_htpasswd(h *HtpasswdFile) {
+	r, err := os.Open(h.Path)
+	if err != nil {
+		panic(err)
+	}
+	csv_reader := csv.NewReader(r)
+	csv_reader.Comma = ':'
+	csv_reader.Comment = '#'
+	csv_reader.TrimLeadingSpace = true
+
+	records, err := csv_reader.ReadAll()
+	if err != nil {
+		panic(err)
+	}
+
+	h.Users = make(map[string]string)
+	for _, record := range records {
+		h.Users[record[0]] = record[1]
+	}
+}
+
+/*
+ SecretProvider implementation based on htpasswd-formated files. Will
+ reload htpasswd file on changes. Will panic on syntax errors in
+ htpasswd files. Realm argument of the SecretProvider is ignored.
+*/
+func HtpasswdFileProvider(filename string) SecretProvider {
+	h := &HtpasswdFile{File: File{Path: filename}}
+	h.Reload = func() { reload_htpasswd(h) }
+	return func(user, realm string) string {
+		h.ReloadIfNeeded()
+		password, exists := h.Users[user]
+		if !exists {
+			return ""
+		}
+		return password
+	}
+}