Merge branch '18696-rnaseq-training' refs #18696
[arvados.git] / services / arv-git-httpd / auth_handler.go
index 6313d50d685e7a17c4854cbb5c62305c905bcb72..13706ae3e83732281e17eb1d397853a3fbb8a548 100644 (file)
+// Copyright (C) The Arvados Authors. All rights reserved.
+//
+// SPDX-License-Identifier: AGPL-3.0
+
 package main
 
 import (
+       "errors"
        "log"
        "net/http"
-       "net/http/cgi"
        "os"
+       "regexp"
        "strings"
        "sync"
        "time"
 
-       "git.curoverse.com/arvados.git/sdk/go/arvadosclient"
+       "git.arvados.org/arvados.git/sdk/go/arvados"
+       "git.arvados.org/arvados.git/sdk/go/arvadosclient"
+       "git.arvados.org/arvados.git/sdk/go/auth"
+       "git.arvados.org/arvados.git/sdk/go/httpserver"
 )
 
-func newArvadosClient() interface{} {
-       arv, err := arvadosclient.MakeArvadosClient()
-       if err != nil {
-               log.Println("MakeArvadosClient:", err)
-               return nil
-       }
-       return &arv
+type authHandler struct {
+       handler    http.Handler
+       clientPool *arvadosclient.ClientPool
+       cluster    *arvados.Cluster
+       setupOnce  sync.Once
 }
 
-var connectionPool = &sync.Pool{New: newArvadosClient}
-
-type spyingResponseWriter struct {
-       http.ResponseWriter
-       wroteStatus *int
-}
+func (h *authHandler) setup() {
+       client, err := arvados.NewClientFromConfig(h.cluster)
+       if err != nil {
+               log.Fatal(err)
+       }
 
-func (w spyingResponseWriter) WriteHeader(s int) {
-       *w.wroteStatus = s
-       w.ResponseWriter.WriteHeader(s)
-}
+       ac, err := arvadosclient.New(client)
+       if err != nil {
+               log.Fatalf("Error setting up arvados client prototype %v", err)
+       }
 
-type authHandler struct {
-       handler *cgi.Handler
+       h.clientPool = &arvadosclient.ClientPool{Prototype: ac}
 }
 
 func (h *authHandler) ServeHTTP(wOrig http.ResponseWriter, r *http.Request) {
+       h.setupOnce.Do(h.setup)
+
        var statusCode int
        var statusText string
-       var username, password string
+       var apiToken string
        var repoName string
-       var wroteStatus int
+       var validAPIToken bool
+
+       w := httpserver.WrapResponseWriter(wOrig)
+
+       if r.Method == "OPTIONS" {
+               method := r.Header.Get("Access-Control-Request-Method")
+               if method != "GET" && method != "POST" {
+                       w.WriteHeader(http.StatusMethodNotAllowed)
+                       return
+               }
+               w.Header().Set("Access-Control-Allow-Headers", "Authorization, Content-Type")
+               w.Header().Set("Access-Control-Allow-Methods", "GET, POST")
+               w.Header().Set("Access-Control-Allow-Origin", "*")
+               w.Header().Set("Access-Control-Max-Age", "86400")
+               w.WriteHeader(http.StatusOK)
+               return
+       }
 
-       w := spyingResponseWriter{wOrig, &wroteStatus}
+       if r.Header.Get("Origin") != "" {
+               // Allow simple cross-origin requests without user
+               // credentials ("user credentials" as defined by CORS,
+               // i.e., cookies, HTTP authentication, and client-side
+               // SSL certificates. See
+               // http://www.w3.org/TR/cors/#user-credentials).
+               w.Header().Set("Access-Control-Allow-Origin", "*")
+       }
 
        defer func() {
-               if wroteStatus == 0 {
-                       // Nobody has called WriteHeader yet: that must be our job.
+               if w.WroteStatus() == 0 {
+                       // Nobody has called WriteHeader yet: that
+                       // must be our job.
                        w.WriteHeader(statusCode)
-                       w.Write([]byte(statusText))
+                       if statusCode >= 400 {
+                               w.Write([]byte(statusText))
+                       }
                }
-               log.Println(quoteStrings(r.RemoteAddr, username, password, wroteStatus, statusText, repoName, r.Method, r.URL.Path)...)
+
+               // If the given password is a valid token, log the first 10 characters of the token.
+               // Otherwise: log the string <invalid> if a password is given, else an empty string.
+               passwordToLog := ""
+               if !validAPIToken {
+                       if len(apiToken) > 0 {
+                               passwordToLog = "<invalid>"
+                       }
+               } else {
+                       passwordToLog = apiToken[0:10]
+               }
+
+               httpserver.Log(r.RemoteAddr, passwordToLog, w.WroteStatus(), statusText, repoName, r.Method, r.URL.Path)
        }()
 
-       // HTTP request username is logged, but unused. Password is an
-       // Arvados API token.
-       username, password, ok := BasicAuth(r)
-       if !ok || username == "" || password == "" {
+       creds := auth.CredentialsFromRequest(r)
+       if len(creds.Tokens) == 0 {
                statusCode, statusText = http.StatusUnauthorized, "no credentials provided"
                w.Header().Add("WWW-Authenticate", "Basic realm=\"git\"")
                return
        }
+       apiToken = creds.Tokens[0]
 
        // Access to paths "/foo/bar.git/*" and "/foo/bar/.git/*" are
        // protected by the permissions on the repository named
        // "foo/bar".
        pathParts := strings.SplitN(r.URL.Path[1:], ".git/", 2)
        if len(pathParts) != 2 {
-               statusCode, statusText = http.StatusBadRequest, "bad request"
+               statusCode, statusText = http.StatusNotFound, "not found"
                return
        }
        repoName = pathParts[0]
        repoName = strings.TrimRight(repoName, "/")
 
-       arv, ok := connectionPool.Get().(*arvadosclient.ArvadosClient)
-       if !ok || arv == nil {
-               statusCode, statusText = http.StatusInternalServerError, "connection pool failed"
+       arv := h.clientPool.Get()
+       if arv == nil {
+               statusCode, statusText = http.StatusInternalServerError, "connection pool failed: "+h.clientPool.Err().Error()
                return
        }
-       defer connectionPool.Put(arv)
+       defer h.clientPool.Put(arv)
 
        // Ask API server whether the repository is readable using
        // this token (by trying to read it!)
-       arv.ApiToken = password
-       reposFound := arvadosclient.Dict{}
-       if err := arv.List("repositories", arvadosclient.Dict{
-               "filters": [][]string{{"name", "=", repoName}},
-       }, &reposFound); err != nil {
+       arv.ApiToken = apiToken
+       repoUUID, err := h.lookupRepo(arv, repoName)
+       if err != nil {
                statusCode, statusText = http.StatusInternalServerError, err.Error()
                return
        }
-       if avail, ok := reposFound["items_available"].(float64); !ok {
-               statusCode, statusText = http.StatusInternalServerError, "bad list response from API"
-               return
-       } else if avail < 1 {
+       validAPIToken = true
+       if repoUUID == "" {
                statusCode, statusText = http.StatusNotFound, "not found"
                return
-       } else if avail > 1 {
-               statusCode, statusText = http.StatusInternalServerError, "name collision"
-               return
        }
 
-       repoUUID := reposFound["items"].([]interface{})[0].(map[string]interface{})["uuid"].(string)
-
        isWrite := strings.HasSuffix(r.URL.Path, "/git-receive-pack")
        if !isWrite {
                statusText = "read"
@@ -135,7 +169,7 @@ func (h *authHandler) ServeHTTP(wOrig http.ResponseWriter, r *http.Request) {
                "/" + repoName + "/.git",
        }
        for _, dir := range tryDirs {
-               if fileInfo, err := os.Stat(theConfig.Root + dir); err != nil {
+               if fileInfo, err := os.Stat(h.cluster.Git.Repositories + dir); err != nil {
                        if !os.IsNotExist(err) {
                                statusCode, statusText = http.StatusInternalServerError, err.Error()
                                return
@@ -147,7 +181,7 @@ func (h *authHandler) ServeHTTP(wOrig http.ResponseWriter, r *http.Request) {
        }
        if rewrittenPath == "" {
                log.Println("WARNING:", repoUUID,
-                       "git directory not found in", theConfig.Root, tryDirs)
+                       "git directory not found in", h.cluster.Git.Repositories, tryDirs)
                // We say "content not found" to disambiguate from the
                // earlier "API says that repo does not exist" error.
                statusCode, statusText = http.StatusNotFound, "content not found"
@@ -155,20 +189,30 @@ func (h *authHandler) ServeHTTP(wOrig http.ResponseWriter, r *http.Request) {
        }
        r.URL.Path = rewrittenPath
 
-       handlerCopy := *h.handler
-       handlerCopy.Env = append(handlerCopy.Env, "REMOTE_USER="+r.RemoteAddr) // Should be username
-       handlerCopy.ServeHTTP(&w, r)
+       h.handler.ServeHTTP(w, r)
 }
 
-var escaper = strings.NewReplacer("\"", "\\\"", "\\", "\\\\", "\n", "\\n")
+var uuidRegexp = regexp.MustCompile(`^[0-9a-z]{5}-s0uqq-[0-9a-z]{15}$`)
 
-// Transform strings so they are safer to write in logs (e.g.,
-// 'foo"bar' becomes '"foo\"bar"'). Non-string args are left alone.
-func quoteStrings(args ...interface{}) []interface{} {
-       for i, arg := range args {
-               if s, ok := arg.(string); ok {
-                       args[i] = "\"" + escaper.Replace(s) + "\""
-               }
+func (h *authHandler) lookupRepo(arv *arvadosclient.ArvadosClient, repoName string) (string, error) {
+       reposFound := arvadosclient.Dict{}
+       var column string
+       if uuidRegexp.MatchString(repoName) {
+               column = "uuid"
+       } else {
+               column = "name"
+       }
+       err := arv.List("repositories", arvadosclient.Dict{
+               "filters": [][]string{{column, "=", repoName}},
+       }, &reposFound)
+       if err != nil {
+               return "", err
+       } else if avail, ok := reposFound["items_available"].(float64); !ok {
+               return "", errors.New("bad list response from API")
+       } else if avail < 1 {
+               return "", nil
+       } else if avail > 1 {
+               return "", errors.New("name collision")
        }
-       return args
+       return reposFound["items"].([]interface{})[0].(map[string]interface{})["uuid"].(string), nil
 }