util/fipstools/acvp/acvptool/acvp.go - boringssl - Git at Google

 // Copyright (c) 2019, Google Inc.
 //
 // Permission to use, copy, modify, and/or distribute this software for any
 // purpose with or without fee is hereby granted, provided that the above
 // copyright notice and this permission notice appear in all copies.
 //
 // THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 // WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 // MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
 // SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 // WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
 // OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
 // CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

 package main

 import (
 	"bufio"
 	"bytes"
 	"crypto"
 	"crypto/hmac"
 	"crypto/sha256"
 	"crypto/x509"
 	"encoding/base64"
 	"encoding/binary"
 	"encoding/json"
 	"encoding/pem"
 	"errors"
 	"flag"
 	"fmt"
 	"io/ioutil"
 	"log"
 	"net/http"
 	neturl "net/url"
 	"os"
 	"path/filepath"
 	"strings"
 	"time"

 	"boringssl.googlesource.com/boringssl/util/fipstools/acvp/acvptool/acvp"
 	"boringssl.googlesource.com/boringssl/util/fipstools/acvp/acvptool/subprocess"
 )

 var (
 	dumpRegcap     = flag.Bool("regcap", false, "Print module capabilities JSON to stdout")
 	configFilename = flag.String("config", "config.json", "Location of the configuration JSON file")
 	jsonInputFile  = flag.String("json", "", "Location of a vector-set input file")
 	runFlag        = flag.String("run", "", "Name of primitive to run tests for")
 	fetchFlag      = flag.String("fetch", "", "Name of primitive to fetch vectors for")
 	wrapperPath    = flag.String("wrapper", "../../../../build/util/fipstools/acvp/modulewrapper/modulewrapper", "Path to the wrapper binary")
 )

 type Config struct {
 	CertPEMFile        string
 	PrivateKeyFile     string
 	PrivateKeyDERFile  string
 	TOTPSecret         string
 	ACVPServer         string
 	SessionTokensCache string
 	LogFile            string
 }

 func isCommentLine(line []byte) bool {
 	var foundCommentStart bool
 	for _, b := range line {
 		if !foundCommentStart {
 			if b == ' ' || b == '\t' {
 				continue
 			}
 			if b != '/' {
 				return false
 			}
 			foundCommentStart = true
 		} else {
 			return b == '/'
 		}
 	}
 	return false
 }

 func jsonFromFile(out interface{}, filename string) error {
 	in, err := os.Open(filename)
 	if err != nil {
 		return err
 	}
 	defer in.Close()

 	scanner := bufio.NewScanner(in)
 	var commentsRemoved bytes.Buffer
 	for scanner.Scan() {
 		if isCommentLine(scanner.Bytes()) {
 			continue
 		}
 		commentsRemoved.Write(scanner.Bytes())
 		commentsRemoved.WriteString("\n")
 	}
 	if err := scanner.Err(); err != nil {
 		return err
 	}

 	decoder := json.NewDecoder(&commentsRemoved)
 	decoder.DisallowUnknownFields()
 	if err := decoder.Decode(out); err != nil {
 		return err
 	}
 	if decoder.More() {
 		return errors.New("trailing garbage found")
 	}
 	return nil
 }

 // TOTP implements the time-based one-time password algorithm with the suggested
 // granularity of 30 seconds. See https://tools.ietf.org/html/rfc6238 and then
 // https://tools.ietf.org/html/rfc4226#section-5.3
 func TOTP(secret []byte) string {
 	const timeStep = 30
 	now := uint64(time.Now().Unix()) / 30
 	var nowBuf [8]byte
 	binary.BigEndian.PutUint64(nowBuf[:], now)
 	mac := hmac.New(sha256.New, secret)
 	mac.Write(nowBuf[:])
 	digest := mac.Sum(nil)
 	value := binary.BigEndian.Uint32(digest[digest[31]&15:])
 	value &= 0x7fffffff
 	value %= 100000000
 	return fmt.Sprintf("%08d", value)
 }

 type Middle interface {
 	Close()
 	Config() ([]byte, error)
 	Process(algorithm string, vectorSet []byte) (interface{}, error)
 }

 func loadCachedSessionTokens(server *acvp.Server, cachePath string) error {
 	cacheDir, err := os.Open(cachePath)
 	if err != nil {
 		if os.IsNotExist(err) {
 			if err := os.Mkdir(cachePath, 0700); err != nil {
 				return fmt.Errorf("Failed to create session token cache directory %q: %s", cachePath, err)
 			}
 			return nil
 		}
 		return fmt.Errorf("Failed to open session token cache directory %q: %s", cachePath, err)
 	}
 	defer cacheDir.Close()
 	names, err := cacheDir.Readdirnames(0)
 	if err != nil {
 		return fmt.Errorf("Failed to list session token cache directory %q: %s", cachePath, err)
 	}

 	loaded := 0
 	for _, name := range names {
 		if !strings.HasSuffix(name, ".token") {
 			continue
 		}
 		path := filepath.Join(cachePath, name)
 		contents, err := ioutil.ReadFile(path)
 		if err != nil {
 			return fmt.Errorf("Failed to read session token cache entry %q: %s", path, err)
 		}
 		urlPath, err := neturl.PathUnescape(name[:len(name)-6])
 		if err != nil {
 			return fmt.Errorf("Failed to unescape token filename %q: %s", name, err)
 		}
 		server.PrefixTokens[urlPath] = string(contents)
 		loaded++
 	}

 	log.Printf("Loaded %d cached tokens", loaded)
 	return nil
 }

 func trimLeadingSlash(s string) string {
 	if strings.HasPrefix(s, "/") {
 		return s[1:]
 	}
 	return s
 }

 // processFile reads a file containing vector sets, at least in the format
 // preferred by our lab, and writes the results to stdout.
 func processFile(filename string, supportedAlgos []map[string]interface{}, middle Middle) error {
 	jsonBytes, err := ioutil.ReadFile(filename)
 	if err != nil {
 		return err
 	}

 	var elements []json.RawMessage
 	if err := json.Unmarshal(jsonBytes, &elements); err != nil {
 		return err
 	}

 	// There must be at least a header and one vector set in the file.
 	if len(elements) < 2 {
 		return fmt.Errorf("only %d elements in JSON array", len(elements))
 	}
 	header := elements[0]

 	// Build a map of which algorithms our Middle supports.
 	algos := make(map[string]struct{})
 	for _, supportedAlgo := range supportedAlgos {
 		algoInterface, ok := supportedAlgo["algorithm"]
 		if !ok {
 			continue
 		}
 		algo, ok := algoInterface.(string)
 		if !ok {
 			continue
 		}
 		algos[algo] = struct{}{}
 	}

 	var result bytes.Buffer
 	result.WriteString("[")
 	headerBytes, err := json.MarshalIndent(header, "", "    ")
 	if err != nil {
 		return err
 	}
 	result.Write(headerBytes)

 	for i, element := range elements[1:] {
 		var commonFields struct {
 			Algo string `json:"algorithm"`
 			ID   uint64 `json:"vsId"`
 		}
 		if err := json.Unmarshal(element, &commonFields); err != nil {
 			return fmt.Errorf("failed to extract common fields from vector set #%d", i+1)
 		}

 		algo := commonFields.Algo
 		if _, ok := algos[algo]; !ok {
 			return fmt.Errorf("vector set #%d contains unsupported algorithm %q", i+1, algo)
 		}

 		replyGroups, err := middle.Process(algo, element)
 		if err != nil {
 			return fmt.Errorf("while processing vector set #%d: %s", i+1, err)
 		}

 		group := map[string]interface{}{
 			"vsId":       commonFields.ID,
 			"testGroups": replyGroups,
 		}
 		replyBytes, err := json.MarshalIndent(group, "", "    ")
 		if err != nil {
 			return err
 		}

 		result.WriteString(",")
 		result.Write(replyBytes)
 	}

 	result.WriteString("]\n")
 	os.Stdout.Write(result.Bytes())

 	return nil
 }

 func main() {
 	flag.Parse()

 	var config Config
 	if err := jsonFromFile(&config, *configFilename); err != nil {
 		log.Fatalf("Failed to load config file: %s", err)
 	}

 	if len(config.TOTPSecret) == 0 {
 		log.Fatal("Config file missing TOTPSecret")
 	}
 	totpSecret, err := base64.StdEncoding.DecodeString(config.TOTPSecret)
 	if err != nil {
 		log.Fatalf("Failed to base64-decode TOTP secret from config file: %s. (Note that the secret _itself_ should be in the config, not the name of a file that contains it.)", err)
 	}

 	if len(config.CertPEMFile) == 0 {
 		log.Fatal("Config file missing CertPEMFile")
 	}
 	certPEM, err := ioutil.ReadFile(config.CertPEMFile)
 	if err != nil {
 		log.Fatalf("failed to read certificate from %q: %s", config.CertPEMFile, err)
 	}
 	block, _ := pem.Decode(certPEM)
 	certDER := block.Bytes

 	if len(config.PrivateKeyDERFile) == 0 && len(config.PrivateKeyFile) == 0 {
 		log.Fatal("Config file missing PrivateKeyDERFile and PrivateKeyFile")
 	}
 	if len(config.PrivateKeyDERFile) != 0 && len(config.PrivateKeyFile) != 0 {
 		log.Fatal("Config file has both PrivateKeyDERFile and PrivateKeyFile. Can only have one.")
 	}
 	privateKeyFile := config.PrivateKeyDERFile
 	if len(config.PrivateKeyFile) > 0 {
 		privateKeyFile = config.PrivateKeyFile
 	}

 	keyBytes, err := ioutil.ReadFile(privateKeyFile)
 	if err != nil {
 		log.Fatalf("failed to read private key from %q: %s", privateKeyFile, err)
 	}

 	var keyDER []byte
 	pemBlock, _ := pem.Decode(keyBytes)
 	if pemBlock != nil {
 		keyDER = pemBlock.Bytes
 	} else {
 		keyDER = keyBytes
 	}

 	var certKey crypto.PrivateKey
 	if certKey, err = x509.ParsePKCS1PrivateKey(keyDER); err != nil {
 		if certKey, err = x509.ParsePKCS8PrivateKey(keyDER); err != nil {
 			log.Fatalf("failed to parse private key from %q: %s", privateKeyFile, err)
 		}
 	}

 	var middle Middle
 	middle, err = subprocess.New(*wrapperPath)
 	if err != nil {
 		log.Fatalf("failed to initialise middle: %s", err)
 	}
 	defer middle.Close()

 	configBytes, err := middle.Config()
 	if err != nil {
 		log.Fatalf("failed to get config from middle: %s", err)
 	}

 	var supportedAlgos []map[string]interface{}
 	if err := json.Unmarshal(configBytes, &supportedAlgos); err != nil {
 		log.Fatalf("failed to parse configuration from Middle: %s", err)
 	}

 	if *dumpRegcap {
 		regcap := []map[string]interface{}{
 			map[string]interface{}{"acvVersion": "1.0"},
 			map[string]interface{}{"algorithms": supportedAlgos},
 		}
 		regcapBytes, err := json.MarshalIndent(regcap, "", "    ")
 		if err != nil {
 			log.Fatalf("failed to marshal regcap: %s", err)
 		}
 		os.Stdout.Write(regcapBytes)
 		os.Stdout.WriteString("\n")
 		os.Exit(0)
 	}

 	if len(*jsonInputFile) > 0 {
 		if err := processFile(*jsonInputFile, supportedAlgos, middle); err != nil {
 			log.Fatalf("failed to process input file: %s", err)
 		}
 		os.Exit(0)
 	}

 	var requestedAlgosFlag string
 	if len(*runFlag) > 0 && len(*fetchFlag) > 0 {
 		log.Fatalf("cannot specify both -run and -fetch")
 	}
 	if len(*runFlag) > 0 {
 		requestedAlgosFlag = *runFlag
 	} else {
 		requestedAlgosFlag = *fetchFlag
 	}

 	runAlgos := make(map[string]bool)
 	if len(requestedAlgosFlag) > 0 {
 		for _, substr := range strings.Split(requestedAlgosFlag, ",") {
 			runAlgos[substr] = false
 		}
 	}

 	var algorithms []map[string]interface{}
 	for _, supportedAlgo := range supportedAlgos {
 		algoInterface, ok := supportedAlgo["algorithm"]
 		if !ok {
 			continue
 		}

 		algo, ok := algoInterface.(string)
 		if !ok {
 			continue
 		}

 		if _, ok := runAlgos[algo]; ok {
 			algorithms = append(algorithms, supportedAlgo)
 			runAlgos[algo] = true
 		}
 	}

 	for algo, recognised := range runAlgos {
 		if !recognised {
 			log.Fatalf("requested algorithm %q was not recognised", algo)
 		}
 	}

 	if len(config.ACVPServer) == 0 {
 		config.ACVPServer = "https://demo.acvts.nist.gov/"
 	}
 	server := acvp.NewServer(config.ACVPServer, config.LogFile, [][]byte{certDER}, certKey, func() string {
 		return TOTP(totpSecret[:])
 	})

 	var sessionTokensCacheDir string
 	if len(config.SessionTokensCache) > 0 {
 		sessionTokensCacheDir = config.SessionTokensCache
 		if strings.HasPrefix(sessionTokensCacheDir, "~/") {
 			home := os.Getenv("HOME")
 			if len(home) == 0 {
 				log.Fatal("~ used in config file but $HOME not set")
 			}
 			sessionTokensCacheDir = filepath.Join(home, sessionTokensCacheDir[2:])
 		}

 		if err := loadCachedSessionTokens(server, sessionTokensCacheDir); err != nil {
 			log.Fatal(err)
 		}
 	}

 	if err := server.Login(); err != nil {
 		log.Fatalf("failed to login: %s", err)
 	}

 	if len(requestedAlgosFlag) == 0 {
 		if interactiveModeSupported {
 			runInteractive(server, config)
 		} else {
 			log.Fatalf("no arguments given but interactive mode not supported")
 		}
 		return
 	}

 	requestBytes, err := json.Marshal(acvp.TestSession{
 		IsSample:    true,
 		Publishable: false,
 		Algorithms:  algorithms,
 	})
 	if err != nil {
 		log.Fatalf("Failed to serialise JSON: %s", err)
 	}

 	var result acvp.TestSession
 	if err := server.Post(&result, "acvp/v1/testSessions", requestBytes); err != nil {
 		log.Fatalf("Request to create test session failed: %s", err)
 	}

 	url := trimLeadingSlash(result.URL)
 	log.Printf("Created test session %q", url)
 	if token := result.AccessToken; len(token) > 0 {
 		server.PrefixTokens[url] = token
 		if len(sessionTokensCacheDir) > 0 {
 			ioutil.WriteFile(filepath.Join(sessionTokensCacheDir, neturl.PathEscape(url))+".token", []byte(token), 0600)
 		}
 	}

 	log.Printf("Have vector sets %v", result.VectorSetURLs)

 	if len(*fetchFlag) > 0 {
 		os.Stdout.WriteString("[\n")
 		json.NewEncoder(os.Stdout).Encode(map[string]interface{}{
 			"url":           url,
 			"vectorSetUrls": result.VectorSetURLs,
 			"time":          time.Now().Format(time.RFC3339),
 		})
 	}

 	for _, setURL := range result.VectorSetURLs {
 		firstTime := true
 		for {
 			if firstTime {
 				log.Printf("Fetching test vectors %q", setURL)
 				firstTime = false
 			}

 			vectorsBytes, err := server.GetBytes(trimLeadingSlash(setURL))
 			if err != nil {
 				log.Fatalf("Failed to fetch vector set %q: %s", setURL, err)
 			}

 			var vectors acvp.Vectors
 			if err := json.Unmarshal(vectorsBytes, &vectors); err != nil {
 				log.Fatalf("Failed to parse vector set from %q: %s", setURL, err)
 			}

 			if retry := vectors.Retry; retry > 0 {
 				log.Printf("Server requested %d seconds delay", retry)
 				if retry > 10 {
 					retry = 10
 				}
 				time.Sleep(time.Duration(retry) * time.Second)
 				continue
 			}

 			if len(*fetchFlag) > 0 {
 				os.Stdout.WriteString(",\n")
 				os.Stdout.Write(vectorsBytes)
 				break
 			}

 			replyGroups, err := middle.Process(vectors.Algo, vectorsBytes)
 			if err != nil {
 				log.Printf("Failed: %s", err)
 				log.Printf("Deleting test set")
 				server.Delete(url)
 				os.Exit(1)
 			}

 			headerBytes, err := json.Marshal(acvp.Vectors{
 				ID:   vectors.ID,
 				Algo: vectors.Algo,
 			})
 			if err != nil {
 				log.Printf("Failed to marshal result: %s", err)
 				log.Printf("Deleting test set")
 				server.Delete(url)
 				os.Exit(1)
 			}

 			var resultBuf bytes.Buffer
 			resultBuf.Write(headerBytes[:len(headerBytes)-1])
 			resultBuf.WriteString(`,"testGroups":`)
 			replyBytes, err := json.Marshal(replyGroups)
 			if err != nil {
 				log.Printf("Failed to marshal result: %s", err)
 				log.Printf("Deleting test set")
 				server.Delete(url)
 				os.Exit(1)
 			}
 			resultBuf.Write(replyBytes)
 			resultBuf.WriteString("}")

 			resultData := resultBuf.Bytes()
 			resultSize := uint64(len(resultData)) + 32 /* for framing overhead */
 			if server.SizeLimit > 0 && resultSize >= server.SizeLimit {
 				// The NIST ACVP server no longer requires the large-upload process,
 				// suggesting that it may no longer be needed.
 				log.Printf("Result is %d bytes, too much given server limit of %d bytes. Using large-upload process.", resultSize, server.SizeLimit)
 				largeRequestBytes, err := json.Marshal(acvp.LargeUploadRequest{
 					Size: resultSize,
 					URL:  setURL,
 				})
 				if err != nil {
 					log.Printf("Failed to marshal large-upload request: %s", err)
 					log.Printf("Deleting test set")
 					server.Delete(url)
 					os.Exit(1)
 				}

 				var largeResponse acvp.LargeUploadResponse
 				if err := server.Post(&largeResponse, "/large", largeRequestBytes); err != nil {
 					log.Fatalf("Failed to request large-upload endpoint: %s", err)
 				}

 				log.Printf("Directed to large-upload endpoint at %q", largeResponse.URL)
 				client := &http.Client{}
 				req, err := http.NewRequest("POST", largeResponse.URL, bytes.NewBuffer(resultData))
 				if err != nil {
 					log.Fatalf("Failed to create POST request: %s", err)
 				}
 				token := largeResponse.AccessToken
 				if len(token) == 0 {
 					token = server.AccessToken
 				}
 				req.Header.Add("Authorization", "Bearer "+token)
 				req.Header.Add("Content-Type", "application/json")
 				resp, err := client.Do(req)
 				if err != nil {
 					log.Fatalf("Failed writing large upload: %s", err)
 				}
 				resp.Body.Close()
 				if resp.StatusCode != 200 {
 					log.Fatalf("Large upload resulted in status code %d", resp.StatusCode)
 				}
 			} else {
 				log.Printf("Result size %d bytes", resultSize)
 				if err := server.Post(nil, trimLeadingSlash(setURL)+"/results", resultData); err != nil {
 					log.Fatalf("Failed to upload results: %s\n", err)
 				}
 			}

 			break
 		}
 	}

 	if len(*fetchFlag) > 0 {
 		os.Stdout.WriteString("]\n")
 		os.Exit(0)
 	}

 FetchResults:
 	for {
 		var results acvp.SessionResults
 		if err := server.Get(&results, trimLeadingSlash(url)+"/results"); err != nil {
 			log.Fatalf("Failed to fetch session results: %s", err)
 		}

 		if results.Passed {
 			log.Print("Test passed")
 			break
 		}

 		for _, result := range results.Results {
 			if result.Status == "incomplete" {
 				log.Print("Server hasn't finished processing results. Waiting 10 seconds.")
 				time.Sleep(10 * time.Second)
 				continue FetchResults
 			}
 		}

 		log.Fatalf("Server did not accept results: %#v", results)
 	}
 }
	// Copyright (c) 2019, Google Inc.
	//
	// Permission to use, copy, modify, and/or distribute this software for any
	// purpose with or without fee is hereby granted, provided that the above
	// copyright notice and this permission notice appear in all copies.
	//
	// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
	// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
	// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
	// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
	// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
	// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
	// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

	package main

	import (
	"bufio"
	"bytes"
	"crypto"
	"crypto/hmac"
	"crypto/sha256"
	"crypto/x509"
	"encoding/base64"
	"encoding/binary"
	"encoding/json"
	"encoding/pem"
	"errors"
	"flag"
	"fmt"
	"io/ioutil"
	"log"
	"net/http"
	neturl "net/url"
	"os"
	"path/filepath"
	"strings"
	"time"

	"boringssl.googlesource.com/boringssl/util/fipstools/acvp/acvptool/acvp"
	"boringssl.googlesource.com/boringssl/util/fipstools/acvp/acvptool/subprocess"
	)

	var (
	dumpRegcap = flag.Bool("regcap", false, "Print module capabilities JSON to stdout")
	configFilename = flag.String("config", "config.json", "Location of the configuration JSON file")
	jsonInputFile = flag.String("json", "", "Location of a vector-set input file")
	runFlag = flag.String("run", "", "Name of primitive to run tests for")
	fetchFlag = flag.String("fetch", "", "Name of primitive to fetch vectors for")
	wrapperPath = flag.String("wrapper", "../../../../build/util/fipstools/acvp/modulewrapper/modulewrapper", "Path to the wrapper binary")
	)

	type Config struct {
	CertPEMFile string
	PrivateKeyFile string
	PrivateKeyDERFile string
	TOTPSecret string
	ACVPServer string
	SessionTokensCache string
	LogFile string
	}

	func isCommentLine(line []byte) bool {
	var foundCommentStart bool
	for _, b := range line {
	if !foundCommentStart {
	if b == ' ' \|\| b == '\t' {
	continue
	}
	if b != '/' {
	return false
	}
	foundCommentStart = true
	} else {
	return b == '/'
	}
	}
	return false
	}

	func jsonFromFile(out interface{}, filename string) error {
	in, err := os.Open(filename)
	if err != nil {
	return err
	}
	defer in.Close()

	scanner := bufio.NewScanner(in)
	var commentsRemoved bytes.Buffer
	for scanner.Scan() {
	if isCommentLine(scanner.Bytes()) {
	continue
	}
	commentsRemoved.Write(scanner.Bytes())
	commentsRemoved.WriteString("\n")
	}
	if err := scanner.Err(); err != nil {
	return err
	}

	decoder := json.NewDecoder(&commentsRemoved)
	decoder.DisallowUnknownFields()
	if err := decoder.Decode(out); err != nil {
	return err
	}
	if decoder.More() {
	return errors.New("trailing garbage found")
	}
	return nil
	}

	// TOTP implements the time-based one-time password algorithm with the suggested
	// granularity of 30 seconds. See https://tools.ietf.org/html/rfc6238 and then
	// https://tools.ietf.org/html/rfc4226#section-5.3
	func TOTP(secret []byte) string {
	const timeStep = 30
	now := uint64(time.Now().Unix()) / 30
	var nowBuf [8]byte
	binary.BigEndian.PutUint64(nowBuf[:], now)
	mac := hmac.New(sha256.New, secret)
	mac.Write(nowBuf[:])
	digest := mac.Sum(nil)
	value := binary.BigEndian.Uint32(digest[digest[31]&15:])
	value &= 0x7fffffff
	value %= 100000000
	return fmt.Sprintf("%08d", value)
	}

	type Middle interface {
	Close()
	Config() ([]byte, error)
	Process(algorithm string, vectorSet []byte) (interface{}, error)
	}

	func loadCachedSessionTokens(server *acvp.Server, cachePath string) error {
	cacheDir, err := os.Open(cachePath)
	if err != nil {
	if os.IsNotExist(err) {
	if err := os.Mkdir(cachePath, 0700); err != nil {
	return fmt.Errorf("Failed to create session token cache directory %q: %s", cachePath, err)
	}
	return nil
	}
	return fmt.Errorf("Failed to open session token cache directory %q: %s", cachePath, err)
	}
	defer cacheDir.Close()
	names, err := cacheDir.Readdirnames(0)
	if err != nil {
	return fmt.Errorf("Failed to list session token cache directory %q: %s", cachePath, err)
	}

	loaded := 0
	for _, name := range names {
	if !strings.HasSuffix(name, ".token") {
	continue
	}
	path := filepath.Join(cachePath, name)
	contents, err := ioutil.ReadFile(path)
	if err != nil {
	return fmt.Errorf("Failed to read session token cache entry %q: %s", path, err)
	}
	urlPath, err := neturl.PathUnescape(name[:len(name)-6])
	if err != nil {
	return fmt.Errorf("Failed to unescape token filename %q: %s", name, err)
	}
	server.PrefixTokens[urlPath] = string(contents)
	loaded++
	}

	log.Printf("Loaded %d cached tokens", loaded)
	return nil
	}

	func trimLeadingSlash(s string) string {
	if strings.HasPrefix(s, "/") {
	return s[1:]
	}
	return s
	}

	// processFile reads a file containing vector sets, at least in the format
	// preferred by our lab, and writes the results to stdout.
	func processFile(filename string, supportedAlgos []map[string]interface{}, middle Middle) error {
	jsonBytes, err := ioutil.ReadFile(filename)
	if err != nil {
	return err
	}

	var elements []json.RawMessage
	if err := json.Unmarshal(jsonBytes, &elements); err != nil {
	return err
	}

	// There must be at least a header and one vector set in the file.
	if len(elements) < 2 {
	return fmt.Errorf("only %d elements in JSON array", len(elements))
	}
	header := elements[0]

	// Build a map of which algorithms our Middle supports.
	algos := make(map[string]struct{})
	for _, supportedAlgo := range supportedAlgos {
	algoInterface, ok := supportedAlgo["algorithm"]
	if !ok {
	continue
	}
	algo, ok := algoInterface.(string)
	if !ok {
	continue
	}
	algos[algo] = struct{}{}
	}

	var result bytes.Buffer
	result.WriteString("[")
	headerBytes, err := json.MarshalIndent(header, "", " ")
	if err != nil {
	return err
	}
	result.Write(headerBytes)

	for i, element := range elements[1:] {
	var commonFields struct {
	Algo string `json:"algorithm"`
	ID uint64 `json:"vsId"`
	}
	if err := json.Unmarshal(element, &commonFields); err != nil {
	return fmt.Errorf("failed to extract common fields from vector set #%d", i+1)
	}

	algo := commonFields.Algo
	if _, ok := algos[algo]; !ok {
	return fmt.Errorf("vector set #%d contains unsupported algorithm %q", i+1, algo)
	}

	replyGroups, err := middle.Process(algo, element)
	if err != nil {
	return fmt.Errorf("while processing vector set #%d: %s", i+1, err)
	}

	group := map[string]interface{}{
	"vsId": commonFields.ID,
	"testGroups": replyGroups,
	}
	replyBytes, err := json.MarshalIndent(group, "", " ")
	if err != nil {
	return err
	}

	result.WriteString(",")
	result.Write(replyBytes)
	}

	result.WriteString("]\n")
	os.Stdout.Write(result.Bytes())

	return nil
	}

	func main() {
	flag.Parse()

	var config Config
	if err := jsonFromFile(&config, *configFilename); err != nil {
	log.Fatalf("Failed to load config file: %s", err)
	}

	if len(config.TOTPSecret) == 0 {
	log.Fatal("Config file missing TOTPSecret")
	}
	totpSecret, err := base64.StdEncoding.DecodeString(config.TOTPSecret)
	if err != nil {
	log.Fatalf("Failed to base64-decode TOTP secret from config file: %s. (Note that the secret _itself_ should be in the config, not the name of a file that contains it.)", err)
	}

	if len(config.CertPEMFile) == 0 {
	log.Fatal("Config file missing CertPEMFile")
	}
	certPEM, err := ioutil.ReadFile(config.CertPEMFile)
	if err != nil {
	log.Fatalf("failed to read certificate from %q: %s", config.CertPEMFile, err)
	}
	block, _ := pem.Decode(certPEM)
	certDER := block.Bytes

	if len(config.PrivateKeyDERFile) == 0 && len(config.PrivateKeyFile) == 0 {
	log.Fatal("Config file missing PrivateKeyDERFile and PrivateKeyFile")
	}
	if len(config.PrivateKeyDERFile) != 0 && len(config.PrivateKeyFile) != 0 {
	log.Fatal("Config file has both PrivateKeyDERFile and PrivateKeyFile. Can only have one.")
	}
	privateKeyFile := config.PrivateKeyDERFile
	if len(config.PrivateKeyFile) > 0 {
	privateKeyFile = config.PrivateKeyFile
	}

	keyBytes, err := ioutil.ReadFile(privateKeyFile)
	if err != nil {
	log.Fatalf("failed to read private key from %q: %s", privateKeyFile, err)
	}

	var keyDER []byte
	pemBlock, _ := pem.Decode(keyBytes)
	if pemBlock != nil {
	keyDER = pemBlock.Bytes
	} else {
	keyDER = keyBytes
	}

	var certKey crypto.PrivateKey
	if certKey, err = x509.ParsePKCS1PrivateKey(keyDER); err != nil {
	if certKey, err = x509.ParsePKCS8PrivateKey(keyDER); err != nil {
	log.Fatalf("failed to parse private key from %q: %s", privateKeyFile, err)
	}
	}

	var middle Middle
	middle, err = subprocess.New(*wrapperPath)
	if err != nil {
	log.Fatalf("failed to initialise middle: %s", err)
	}
	defer middle.Close()

	configBytes, err := middle.Config()
	if err != nil {
	log.Fatalf("failed to get config from middle: %s", err)
	}

	var supportedAlgos []map[string]interface{}
	if err := json.Unmarshal(configBytes, &supportedAlgos); err != nil {
	log.Fatalf("failed to parse configuration from Middle: %s", err)
	}

	if *dumpRegcap {
	regcap := []map[string]interface{}{
	map[string]interface{}{"acvVersion": "1.0"},
	map[string]interface{}{"algorithms": supportedAlgos},
	}
	regcapBytes, err := json.MarshalIndent(regcap, "", " ")
	if err != nil {
	log.Fatalf("failed to marshal regcap: %s", err)
	}
	os.Stdout.Write(regcapBytes)
	os.Stdout.WriteString("\n")
	os.Exit(0)
	}

	if len(*jsonInputFile) > 0 {
	if err := processFile(*jsonInputFile, supportedAlgos, middle); err != nil {
	log.Fatalf("failed to process input file: %s", err)
	}
	os.Exit(0)
	}

	var requestedAlgosFlag string
	if len(runFlag) > 0 && len(fetchFlag) > 0 {
	log.Fatalf("cannot specify both -run and -fetch")
	}
	if len(*runFlag) > 0 {
	requestedAlgosFlag = *runFlag
	} else {
	requestedAlgosFlag = *fetchFlag
	}

	runAlgos := make(map[string]bool)
	if len(requestedAlgosFlag) > 0 {
	for _, substr := range strings.Split(requestedAlgosFlag, ",") {
	runAlgos[substr] = false
	}
	}

	var algorithms []map[string]interface{}
	for _, supportedAlgo := range supportedAlgos {
	algoInterface, ok := supportedAlgo["algorithm"]
	if !ok {
	continue
	}

	algo, ok := algoInterface.(string)
	if !ok {
	continue
	}

	if _, ok := runAlgos[algo]; ok {
	algorithms = append(algorithms, supportedAlgo)
	runAlgos[algo] = true
	}
	}

	for algo, recognised := range runAlgos {
	if !recognised {
	log.Fatalf("requested algorithm %q was not recognised", algo)
	}
	}

	if len(config.ACVPServer) == 0 {
	config.ACVPServer = "https://demo.acvts.nist.gov/"
	}
	server := acvp.NewServer(config.ACVPServer, config.LogFile, [][]byte{certDER}, certKey, func() string {
	return TOTP(totpSecret[:])
	})

	var sessionTokensCacheDir string
	if len(config.SessionTokensCache) > 0 {
	sessionTokensCacheDir = config.SessionTokensCache
	if strings.HasPrefix(sessionTokensCacheDir, "~/") {
	home := os.Getenv("HOME")
	if len(home) == 0 {
	log.Fatal("~ used in config file but $HOME not set")
	}
	sessionTokensCacheDir = filepath.Join(home, sessionTokensCacheDir[2:])
	}

	if err := loadCachedSessionTokens(server, sessionTokensCacheDir); err != nil {
	log.Fatal(err)
	}
	}

	if err := server.Login(); err != nil {
	log.Fatalf("failed to login: %s", err)
	}

	if len(requestedAlgosFlag) == 0 {
	if interactiveModeSupported {
	runInteractive(server, config)
	} else {
	log.Fatalf("no arguments given but interactive mode not supported")
	}
	return
	}

	requestBytes, err := json.Marshal(acvp.TestSession{
	IsSample: true,
	Publishable: false,
	Algorithms: algorithms,
	})
	if err != nil {
	log.Fatalf("Failed to serialise JSON: %s", err)
	}

	var result acvp.TestSession
	if err := server.Post(&result, "acvp/v1/testSessions", requestBytes); err != nil {
	log.Fatalf("Request to create test session failed: %s", err)
	}

	url := trimLeadingSlash(result.URL)
	log.Printf("Created test session %q", url)
	if token := result.AccessToken; len(token) > 0 {
	server.PrefixTokens[url] = token
	if len(sessionTokensCacheDir) > 0 {
	ioutil.WriteFile(filepath.Join(sessionTokensCacheDir, neturl.PathEscape(url))+".token", []byte(token), 0600)
	}
	}

	log.Printf("Have vector sets %v", result.VectorSetURLs)

	if len(*fetchFlag) > 0 {
	os.Stdout.WriteString("[\n")
	json.NewEncoder(os.Stdout).Encode(map[string]interface{}{
	"url": url,
	"vectorSetUrls": result.VectorSetURLs,
	"time": time.Now().Format(time.RFC3339),
	})
	}

	for _, setURL := range result.VectorSetURLs {
	firstTime := true
	for {
	if firstTime {
	log.Printf("Fetching test vectors %q", setURL)
	firstTime = false
	}

	vectorsBytes, err := server.GetBytes(trimLeadingSlash(setURL))
	if err != nil {
	log.Fatalf("Failed to fetch vector set %q: %s", setURL, err)
	}

	var vectors acvp.Vectors
	if err := json.Unmarshal(vectorsBytes, &vectors); err != nil {
	log.Fatalf("Failed to parse vector set from %q: %s", setURL, err)
	}

	if retry := vectors.Retry; retry > 0 {
	log.Printf("Server requested %d seconds delay", retry)
	if retry > 10 {
	retry = 10
	}
	time.Sleep(time.Duration(retry) * time.Second)
	continue
	}

	if len(*fetchFlag) > 0 {
	os.Stdout.WriteString(",\n")
	os.Stdout.Write(vectorsBytes)
	break
	}

	replyGroups, err := middle.Process(vectors.Algo, vectorsBytes)
	if err != nil {
	log.Printf("Failed: %s", err)
	log.Printf("Deleting test set")
	server.Delete(url)
	os.Exit(1)
	}

	headerBytes, err := json.Marshal(acvp.Vectors{
	ID: vectors.ID,
	Algo: vectors.Algo,
	})
	if err != nil {
	log.Printf("Failed to marshal result: %s", err)
	log.Printf("Deleting test set")
	server.Delete(url)
	os.Exit(1)
	}

	var resultBuf bytes.Buffer
	resultBuf.Write(headerBytes[:len(headerBytes)-1])
	resultBuf.WriteString(`,"testGroups":`)
	replyBytes, err := json.Marshal(replyGroups)
	if err != nil {
	log.Printf("Failed to marshal result: %s", err)
	log.Printf("Deleting test set")
	server.Delete(url)
	os.Exit(1)
	}
	resultBuf.Write(replyBytes)
	resultBuf.WriteString("}")

	resultData := resultBuf.Bytes()
	resultSize := uint64(len(resultData)) + 32 /* for framing overhead */
	if server.SizeLimit > 0 && resultSize >= server.SizeLimit {
	// The NIST ACVP server no longer requires the large-upload process,
	// suggesting that it may no longer be needed.
	log.Printf("Result is %d bytes, too much given server limit of %d bytes. Using large-upload process.", resultSize, server.SizeLimit)
	largeRequestBytes, err := json.Marshal(acvp.LargeUploadRequest{
	Size: resultSize,
	URL: setURL,
	})
	if err != nil {
	log.Printf("Failed to marshal large-upload request: %s", err)
	log.Printf("Deleting test set")
	server.Delete(url)
	os.Exit(1)
	}

	var largeResponse acvp.LargeUploadResponse
	if err := server.Post(&largeResponse, "/large", largeRequestBytes); err != nil {
	log.Fatalf("Failed to request large-upload endpoint: %s", err)
	}

	log.Printf("Directed to large-upload endpoint at %q", largeResponse.URL)
	client := &http.Client{}
	req, err := http.NewRequest("POST", largeResponse.URL, bytes.NewBuffer(resultData))
	if err != nil {
	log.Fatalf("Failed to create POST request: %s", err)
	}
	token := largeResponse.AccessToken
	if len(token) == 0 {
	token = server.AccessToken
	}
	req.Header.Add("Authorization", "Bearer "+token)
	req.Header.Add("Content-Type", "application/json")
	resp, err := client.Do(req)
	if err != nil {
	log.Fatalf("Failed writing large upload: %s", err)
	}
	resp.Body.Close()
	if resp.StatusCode != 200 {
	log.Fatalf("Large upload resulted in status code %d", resp.StatusCode)
	}
	} else {
	log.Printf("Result size %d bytes", resultSize)
	if err := server.Post(nil, trimLeadingSlash(setURL)+"/results", resultData); err != nil {
	log.Fatalf("Failed to upload results: %s\n", err)
	}
	}

	break
	}
	}

	if len(*fetchFlag) > 0 {
	os.Stdout.WriteString("]\n")
	os.Exit(0)
	}

	FetchResults:
	for {
	var results acvp.SessionResults
	if err := server.Get(&results, trimLeadingSlash(url)+"/results"); err != nil {
	log.Fatalf("Failed to fetch session results: %s", err)
	}

	if results.Passed {
	log.Print("Test passed")
	break
	}

	for _, result := range results.Results {
	if result.Status == "incomplete" {
	log.Print("Server hasn't finished processing results. Waiting 10 seconds.")
	time.Sleep(10 * time.Second)
	continue FetchResults
	}
	}

	log.Fatalf("Server did not accept results: %#v", results)
	}
	}