The Tor Browser: netwerk/protocol/http/nsHttpDigestAuth.cpp@deefc01c0e14 (annotated)

netwerk/protocol/http/nsHttpDigestAuth.cpp@deefc01c0e14 (annotated)

netwerk/protocol/http/nsHttpDigestAuth.cpp

Thu, 15 Jan 2015 21:03:48 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 15 Jan 2015 21:03:48 +0100
branch: TOR_BUG_9701
changeset 11: deefc01c0e14
permissions: -rw-r--r--

Integrate friendly tips from Tor colleagues to make (or not) 4.5 alpha 3;
This includes removal of overloaded (but unused) methods, and addition of
a overlooked call to DataStruct::SetData(nsISupports, uint32_t, bool.)

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 // HttpLog.h should generally be included first
 #include "HttpLog.h"
 #include "nsHttp.h"
 #include "nsHttpDigestAuth.h"
 #include "nsIHttpAuthenticableChannel.h"
 #include "nsISupportsPrimitives.h"
 #include "nsIURI.h"
 #include "nsString.h"
 #include "nsEscape.h"
 #include "nsNetCID.h"
 #include "prprf.h"
 #include "nsCRT.h"
 #include "nsICryptoHash.h"
 namespace mozilla {
 namespace net {
 //-----------------------------------------------------------------------------
 // nsHttpDigestAuth <public>
 //-----------------------------------------------------------------------------
 nsHttpDigestAuth::nsHttpDigestAuth()
 {}
 nsHttpDigestAuth::~nsHttpDigestAuth()
 {}
 //-----------------------------------------------------------------------------
 // nsHttpDigestAuth::nsISupports
 //-----------------------------------------------------------------------------
 NS_IMPL_ISUPPORTS(nsHttpDigestAuth, nsIHttpAuthenticator)
 //-----------------------------------------------------------------------------
 // nsHttpDigestAuth <protected>
 //-----------------------------------------------------------------------------
 nsresult
 nsHttpDigestAuth::MD5Hash(const char *buf, uint32_t len)
 {
   nsresult rv;
   // Cache a reference to the nsICryptoHash instance since we'll be calling
   // this function frequently.
   if (!mVerifier) {
     mVerifier = do_CreateInstance(NS_CRYPTO_HASH_CONTRACTID, &rv);
     if (NS_FAILED(rv)) {
       LOG(("nsHttpDigestAuth: no crypto hash!\n"));
       return rv;
     }
   }
   rv = mVerifier->Init(nsICryptoHash::MD5);
   if (NS_FAILED(rv)) return rv;
   rv = mVerifier->Update((unsigned char*)buf, len);
   if (NS_FAILED(rv)) return rv;
   nsAutoCString hashString;
   rv = mVerifier->Finish(false, hashString);
   if (NS_FAILED(rv)) return rv;
   NS_ENSURE_STATE(hashString.Length() == sizeof(mHashBuf));
   memcpy(mHashBuf, hashString.get(), hashString.Length());
   return rv;
 }
 nsresult
 nsHttpDigestAuth::GetMethodAndPath(nsIHttpAuthenticableChannel *authChannel,
                                    bool                         isProxyAuth,
                                    nsCString                   &httpMethod,
                                    nsCString                   &path)
 {
   nsresult rv, rv2;
   nsCOMPtr<nsIURI> uri;
   rv = authChannel->GetURI(getter_AddRefs(uri));
   if (NS_SUCCEEDED(rv)) {
     bool proxyMethodIsConnect;
     rv = authChannel->GetProxyMethodIsConnect(&proxyMethodIsConnect);
     if (NS_SUCCEEDED(rv)) {
       if (proxyMethodIsConnect && isProxyAuth) {
         httpMethod.AssignLiteral("CONNECT");
         //
         // generate hostname:port string. (unfortunately uri->GetHostPort
         // leaves out the port if it matches the default value, so we can't
         // just call it.)
         //
         int32_t port;
         rv = uri->GetAsciiHost(path);
         rv2 = uri->GetPort(&port);
         if (NS_SUCCEEDED(rv) && NS_SUCCEEDED(rv2)) {
           path.Append(':');
           path.AppendInt(port < 0 ? NS_HTTPS_DEFAULT_PORT : port);
         }
       }
       else {
         rv = authChannel->GetRequestMethod(httpMethod);
         rv2 = uri->GetPath(path);
         if (NS_SUCCEEDED(rv) && NS_SUCCEEDED(rv2)) {
           //
           // strip any fragment identifier from the URL path.
           //
           int32_t ref = path.RFindChar('#');
           if (ref != kNotFound)
             path.Truncate(ref);
           //
           // make sure we escape any UTF-8 characters in the URI path.  the
           // digest auth uri attribute needs to match the request-URI.
           //
           // XXX we should really ask the HTTP channel for this string
           // instead of regenerating it here.
           //
           nsAutoCString buf;
           path = NS_EscapeURL(path, esc_OnlyNonASCII, buf);
         }
       }
     }
   }
   return rv;
 }
 //-----------------------------------------------------------------------------
 // nsHttpDigestAuth::nsIHttpAuthenticator
 //-----------------------------------------------------------------------------
 NS_IMETHODIMP
 nsHttpDigestAuth::ChallengeReceived(nsIHttpAuthenticableChannel *authChannel,
                                     const char *challenge,
                                     bool isProxyAuth,
                                     nsISupports **sessionState,
                                     nsISupports **continuationState,
                                     bool *result)
 {
   nsAutoCString realm, domain, nonce, opaque;
   bool stale;
   uint16_t algorithm, qop;
   nsresult rv = ParseChallenge(challenge, realm, domain, nonce, opaque,
                                &stale, &algorithm, &qop);
   if (NS_FAILED(rv)) return rv;
   // if the challenge has the "stale" flag set, then the user identity is not
   // necessarily invalid.  by returning FALSE here we can suppress username
   // and password prompting that usually accompanies a 401/407 challenge.
   *result = !stale;
   // clear any existing nonce_count since we have a new challenge.
   NS_IF_RELEASE(*sessionState);
   return NS_OK;
 }
 NS_IMETHODIMP
 nsHttpDigestAuth::GenerateCredentials(nsIHttpAuthenticableChannel *authChannel,
                                       const char *challenge,
                                       bool isProxyAuth,
                                       const char16_t *userdomain,
                                       const char16_t *username,
                                       const char16_t *password,
                                       nsISupports **sessionState,
                                       nsISupports **continuationState,
                                       uint32_t *aFlags,
                                       char **creds)
 {
   LOG(("nsHttpDigestAuth::GenerateCredentials [challenge=%s]\n", challenge));
   NS_ENSURE_ARG_POINTER(creds);
   *aFlags = 0;
   bool isDigestAuth = !PL_strncasecmp(challenge, "digest ", 7);
   NS_ENSURE_TRUE(isDigestAuth, NS_ERROR_UNEXPECTED);
   // IIS implementation requires extra quotes
   bool requireExtraQuotes = false;
   {
     nsAutoCString serverVal;
     authChannel->GetServerResponseHeader(serverVal);
     if (!serverVal.IsEmpty()) {
       requireExtraQuotes = !PL_strncasecmp(serverVal.get(), "Microsoft-IIS", 13);
     }
   }
   nsresult rv;
   nsAutoCString httpMethod;
   nsAutoCString path;
   rv = GetMethodAndPath(authChannel, isProxyAuth, httpMethod, path);
   if (NS_FAILED(rv)) return rv;
   nsAutoCString realm, domain, nonce, opaque;
   bool stale;
   uint16_t algorithm, qop;
   rv = ParseChallenge(challenge, realm, domain, nonce, opaque,
                       &stale, &algorithm, &qop);
   if (NS_FAILED(rv)) {
     LOG(("nsHttpDigestAuth::GenerateCredentials [ParseChallenge failed rv=%x]\n", rv));
     return rv;
   }
   char ha1_digest[EXPANDED_DIGEST_LENGTH+1];
   char ha2_digest[EXPANDED_DIGEST_LENGTH+1];
   char response_digest[EXPANDED_DIGEST_LENGTH+1];
   char upload_data_digest[EXPANDED_DIGEST_LENGTH+1];
   if (qop & QOP_AUTH_INT) {
     // we do not support auth-int "quality of protection" currently
     qop &= ~QOP_AUTH_INT;
     NS_WARNING("no support for Digest authentication with data integrity quality of protection");
     /* TODO: to support auth-int, we need to get an MD5 digest of
      * TODO: the data uploaded with this request.
      * TODO: however, i am not sure how to read in the file in without
      * TODO: disturbing the channel''s use of it. do i need to copy it
      * TODO: somehow?
      */
 #if 0
     if (http_channel != nullptr)
     {
       nsIInputStream * upload;
       nsCOMPtr<nsIUploadChannel> uc = do_QueryInterface(http_channel);
       NS_ENSURE_TRUE(uc, NS_ERROR_UNEXPECTED);
       uc->GetUploadStream(&upload);
       if (upload) {
         char * upload_buffer;
         int upload_buffer_length = 0;
         //TODO: read input stream into buffer
         const char * digest = (const char*)
         nsNetwerkMD5Digest(upload_buffer, upload_buffer_length);
         ExpandToHex(digest, upload_data_digest);
         NS_RELEASE(upload);
       }
     }
 #endif
   }
   if (!(algorithm & ALGO_MD5 || algorithm & ALGO_MD5_SESS)) {
     // they asked only for algorithms that we do not support
     NS_WARNING("unsupported algorithm requested by Digest authentication");
     return NS_ERROR_NOT_IMPLEMENTED;
   }
   //
   // the following are for increasing security.  see RFC 2617 for more
   // information.
   //
   // nonce_count allows the server to keep track of auth challenges (to help
   // prevent spoofing). we increase this count every time.
   //
   char nonce_count[NONCE_COUNT_LENGTH+1] = "00000001"; // in hex
   if (*sessionState) {
     nsCOMPtr<nsISupportsPRUint32> v(do_QueryInterface(*sessionState));
     if (v) {
       uint32_t nc;
       v->GetData(&nc);
       PR_snprintf(nonce_count, sizeof(nonce_count), "%08x", ++nc);
       v->SetData(nc);
     }
   }
   else {
     nsCOMPtr<nsISupportsPRUint32> v(
             do_CreateInstance(NS_SUPPORTS_PRUINT32_CONTRACTID));
     if (v) {
       v->SetData(1);
       NS_ADDREF(*sessionState = v);
     }
   }
   LOG(("   nonce_count=%s\n", nonce_count));
   //
   // this lets the client verify the server response (via a server
   // returned Authentication-Info header). also used for session info.
   //
   nsAutoCString cnonce;
   static const char hexChar[] = "0123456789abcdef";
   for (int i=0; i<16; ++i) {
     cnonce.Append(hexChar[(int)(15.0 * rand()/(RAND_MAX + 1.0))]);
   }
   LOG(("   cnonce=%s\n", cnonce.get()));
   //
   // calculate credentials
   //
   NS_ConvertUTF16toUTF8 cUser(username), cPass(password);
   rv = CalculateHA1(cUser, cPass, realm, algorithm, nonce, cnonce, ha1_digest);
   if (NS_FAILED(rv)) return rv;
   rv = CalculateHA2(httpMethod, path, qop, upload_data_digest, ha2_digest);
   if (NS_FAILED(rv)) return rv;
   rv = CalculateResponse(ha1_digest, ha2_digest, nonce, qop, nonce_count,
                          cnonce, response_digest);
   if (NS_FAILED(rv)) return rv;
   //
   // Values that need to match the quoted-string production from RFC 2616:
   //
   //    username
   //    realm
   //    nonce
   //    opaque
   //    cnonce
   //
   nsAutoCString authString;
   authString.AssignLiteral("Digest username=");
   rv = AppendQuotedString(cUser, authString);
   NS_ENSURE_SUCCESS(rv, rv);
   authString.AppendLiteral(", realm=");
   rv = AppendQuotedString(realm, authString);
   NS_ENSURE_SUCCESS(rv, rv);
   authString.AppendLiteral(", nonce=");
   rv = AppendQuotedString(nonce, authString);
   NS_ENSURE_SUCCESS(rv, rv);
   authString.AppendLiteral(", uri=\"");
   authString += path;
   if (algorithm & ALGO_SPECIFIED) {
     authString.AppendLiteral("\", algorithm=");
     if (algorithm & ALGO_MD5_SESS)
       authString.AppendLiteral("MD5-sess");
     else
       authString.AppendLiteral("MD5");
   } else {
     authString += '\"';
   }
   authString.AppendLiteral(", response=\"");
   authString += response_digest;
   authString += '\"';
   if (!opaque.IsEmpty()) {
     authString.AppendLiteral(", opaque=");
     rv = AppendQuotedString(opaque, authString);
     NS_ENSURE_SUCCESS(rv, rv);
   }
   if (qop) {
     authString.AppendLiteral(", qop=");
     if (requireExtraQuotes)
       authString += '\"';
     authString.AppendLiteral("auth");
     if (qop & QOP_AUTH_INT)
       authString.AppendLiteral("-int");
     if (requireExtraQuotes)
       authString += '\"';
     authString.AppendLiteral(", nc=");
     authString += nonce_count;
     authString.AppendLiteral(", cnonce=");
     rv = AppendQuotedString(cnonce, authString);
     NS_ENSURE_SUCCESS(rv, rv);
   }
   *creds = ToNewCString(authString);
   return NS_OK;
 }
 NS_IMETHODIMP
 nsHttpDigestAuth::GetAuthFlags(uint32_t *flags)
 {
   *flags = REQUEST_BASED | REUSABLE_CHALLENGE | IDENTITY_ENCRYPTED;
   //
   // NOTE: digest auth credentials must be uniquely computed for each request,
   //       so we do not set the REUSABLE_CREDENTIALS flag.
   //
   return NS_OK;
 }
 nsresult
 nsHttpDigestAuth::CalculateResponse(const char * ha1_digest,
                                     const char * ha2_digest,
                                     const nsAFlatCString & nonce,
                                     uint16_t qop,
                                     const char * nonce_count,
                                     const nsAFlatCString & cnonce,
                                     char * result)
 {
   uint32_t len = 2*EXPANDED_DIGEST_LENGTH + nonce.Length() + 2;
   if (qop & QOP_AUTH || qop & QOP_AUTH_INT) {
     len += cnonce.Length() + NONCE_COUNT_LENGTH + 3;
     if (qop & QOP_AUTH_INT)
       len += 8; // length of "auth-int"
     else
       len += 4; // length of "auth"
   }
   nsAutoCString contents;
   contents.SetCapacity(len);
   contents.Assign(ha1_digest, EXPANDED_DIGEST_LENGTH);
   contents.Append(':');
   contents.Append(nonce);
   contents.Append(':');
   if (qop & QOP_AUTH || qop & QOP_AUTH_INT) {
     contents.Append(nonce_count, NONCE_COUNT_LENGTH);
     contents.Append(':');
     contents.Append(cnonce);
     contents.Append(':');
     if (qop & QOP_AUTH_INT)
       contents.AppendLiteral("auth-int:");
     else
       contents.AppendLiteral("auth:");
   }
   contents.Append(ha2_digest, EXPANDED_DIGEST_LENGTH);
   nsresult rv = MD5Hash(contents.get(), contents.Length());
   if (NS_SUCCEEDED(rv))
     rv = ExpandToHex(mHashBuf, result);
   return rv;
 }
 nsresult
 nsHttpDigestAuth::ExpandToHex(const char * digest, char * result)
 {
   int16_t index, value;
   for (index = 0; index < DIGEST_LENGTH; index++) {
     value = (digest[index] >> 4) & 0xf;
     if (value < 10)
       result[index*2] = value + '0';
     else
       result[index*2] = value - 10 + 'a';
     value = digest[index] & 0xf;
     if (value < 10)
       result[(index*2)+1] = value + '0';
     else
       result[(index*2)+1] = value - 10 + 'a';
   }
   result[EXPANDED_DIGEST_LENGTH] = 0;
   return NS_OK;
 }
 nsresult
 nsHttpDigestAuth::CalculateHA1(const nsAFlatCString & username,
                                const nsAFlatCString & password,
                                const nsAFlatCString & realm,
                                uint16_t algorithm,
                                const nsAFlatCString & nonce,
                                const nsAFlatCString & cnonce,
                                char * result)
 {
   int16_t len = username.Length() + password.Length() + realm.Length() + 2;
   if (algorithm & ALGO_MD5_SESS) {
     int16_t exlen = EXPANDED_DIGEST_LENGTH + nonce.Length() + cnonce.Length() + 2;
     if (exlen > len)
         len = exlen;
   }
   nsAutoCString contents;
   contents.SetCapacity(len + 1);
   contents.Assign(username);
   contents.Append(':');
   contents.Append(realm);
   contents.Append(':');
   contents.Append(password);
   nsresult rv;
   rv = MD5Hash(contents.get(), contents.Length());
   if (NS_FAILED(rv))
     return rv;
   if (algorithm & ALGO_MD5_SESS) {
     char part1[EXPANDED_DIGEST_LENGTH+1];
     ExpandToHex(mHashBuf, part1);
     contents.Assign(part1, EXPANDED_DIGEST_LENGTH);
     contents.Append(':');
     contents.Append(nonce);
     contents.Append(':');
     contents.Append(cnonce);
     rv = MD5Hash(contents.get(), contents.Length());
     if (NS_FAILED(rv))
       return rv;
   }
   return ExpandToHex(mHashBuf, result);
 }
 nsresult
 nsHttpDigestAuth::CalculateHA2(const nsAFlatCString & method,
                                const nsAFlatCString & path,
                                uint16_t qop,
                                const char * bodyDigest,
                                char * result)
 {
   uint16_t methodLen = method.Length();
   uint32_t pathLen = path.Length();
   uint32_t len = methodLen + pathLen + 1;
   if (qop & QOP_AUTH_INT) {
     len += EXPANDED_DIGEST_LENGTH + 1;
   }
   nsAutoCString contents;
   contents.SetCapacity(len);
   contents.Assign(method);
   contents.Append(':');
   contents.Append(path);
   if (qop & QOP_AUTH_INT) {
     contents.Append(':');
     contents.Append(bodyDigest, EXPANDED_DIGEST_LENGTH);
   }
   nsresult rv = MD5Hash(contents.get(), contents.Length());
   if (NS_SUCCEEDED(rv))
     rv = ExpandToHex(mHashBuf, result);
   return rv;
 }
 nsresult
 nsHttpDigestAuth::ParseChallenge(const char * challenge,
                                  nsACString & realm,
                                  nsACString & domain,
                                  nsACString & nonce,
                                  nsACString & opaque,
                                  bool * stale,
                                  uint16_t * algorithm,
                                  uint16_t * qop)
 {
   // put an absurd, but maximum, length cap on the challenge so
   // that calculations are 32 bit safe
   if (strlen(challenge) > 16000000) {
     return NS_ERROR_INVALID_ARG;
   }
   const char *p = challenge + 7; // first 7 characters are "Digest "
   *stale = false;
   *algorithm = ALGO_MD5; // default is MD5
   *qop = 0;
   for (;;) {
     while (*p && (*p == ',' || nsCRT::IsAsciiSpace(*p)))
       ++p;
     if (!*p)
       break;
     // name
     int32_t nameStart = (p - challenge);
     while (*p && !nsCRT::IsAsciiSpace(*p) && *p != '=')
       ++p;
     if (!*p)
       return NS_ERROR_INVALID_ARG;
     int32_t nameLength = (p - challenge) - nameStart;
     while (*p && (nsCRT::IsAsciiSpace(*p) || *p == '='))
       ++p;
     if (!*p)
       return NS_ERROR_INVALID_ARG;
     bool quoted = false;
     if (*p == '"') {
       ++p;
       quoted = true;
     }
     // value
     int32_t valueStart = (p - challenge);
     int32_t valueLength = 0;
     if (quoted) {
       while (*p && *p != '"')
         ++p;
       if (*p != '"')
         return NS_ERROR_INVALID_ARG;
       valueLength = (p - challenge) - valueStart;
       ++p;
     } else {
       while (*p && !nsCRT::IsAsciiSpace(*p) && *p != ',')
         ++p;
       valueLength = (p - challenge) - valueStart;
     }
     // extract information
     if (nameLength == 5 &&
         nsCRT::strncasecmp(challenge+nameStart, "realm", 5) == 0)
     {
       realm.Assign(challenge+valueStart, valueLength);
     }
     else if (nameLength == 6 &&
         nsCRT::strncasecmp(challenge+nameStart, "domain", 6) == 0)
     {
       domain.Assign(challenge+valueStart, valueLength);
     }
     else if (nameLength == 5 &&
         nsCRT::strncasecmp(challenge+nameStart, "nonce", 5) == 0)
     {
       nonce.Assign(challenge+valueStart, valueLength);
     }
     else if (nameLength == 6 &&
         nsCRT::strncasecmp(challenge+nameStart, "opaque", 6) == 0)
     {
       opaque.Assign(challenge+valueStart, valueLength);
     }
     else if (nameLength == 5 &&
         nsCRT::strncasecmp(challenge+nameStart, "stale", 5) == 0)
     {
       if (nsCRT::strncasecmp(challenge+valueStart, "true", 4) == 0)
         *stale = true;
       else
         *stale = false;
     }
     else if (nameLength == 9 &&
         nsCRT::strncasecmp(challenge+nameStart, "algorithm", 9) == 0)
     {
       // we want to clear the default, so we use = not |= here
       *algorithm = ALGO_SPECIFIED;
       if (valueLength == 3 &&
           nsCRT::strncasecmp(challenge+valueStart, "MD5", 3) == 0)
         *algorithm |= ALGO_MD5;
       else if (valueLength == 8 &&
           nsCRT::strncasecmp(challenge+valueStart, "MD5-sess", 8) == 0)
         *algorithm |= ALGO_MD5_SESS;
     }
     else if (nameLength == 3 &&
         nsCRT::strncasecmp(challenge+nameStart, "qop", 3) == 0)
     {
       int32_t ipos = valueStart;
       while (ipos < valueStart+valueLength) {
         while (ipos < valueStart+valueLength &&
                (nsCRT::IsAsciiSpace(challenge[ipos]) ||
                 challenge[ipos] == ','))
           ipos++;
         int32_t algostart = ipos;
         while (ipos < valueStart+valueLength &&
                !nsCRT::IsAsciiSpace(challenge[ipos]) &&
                challenge[ipos] != ',')
           ipos++;
         if ((ipos - algostart) == 4 &&
             nsCRT::strncasecmp(challenge+algostart, "auth", 4) == 0)
           *qop |= QOP_AUTH;
         else if ((ipos - algostart) == 8 &&
             nsCRT::strncasecmp(challenge+algostart, "auth-int", 8) == 0)
           *qop |= QOP_AUTH_INT;
       }
     }
   }
   return NS_OK;
 }
 nsresult
 nsHttpDigestAuth::AppendQuotedString(const nsACString & value,
                                      nsACString & aHeaderLine)
 {
   nsAutoCString quoted;
   nsACString::const_iterator s, e;
   value.BeginReading(s);
   value.EndReading(e);
   //
   // Encode string according to RFC 2616 quoted-string production
   //
   quoted.Append('"');
   for ( ; s != e; ++s) {
     //
     // CTL = <any US-ASCII control character (octets 0 - 31) and DEL (127)>
     //
     if (*s <= 31 || *s == 127) {
       return NS_ERROR_FAILURE;
     }
     // Escape two syntactically significant characters
     if (*s == '"' || *s == '\\') {
       quoted.Append('\\');
     }
     quoted.Append(*s);
   }
   // FIXME: bug 41489
   // We should RFC2047-encode non-Latin-1 values according to spec
   quoted.Append('"');
   aHeaderLine.Append(quoted);
   return NS_OK;
 }
 } // namespace mozilla::net
 } // namespace mozilla
 // vim: ts=2 sw=2

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netwerk/protocol/http/nsHttpDigestAuth.cpp@deefc01c0e14 (annotated)

netwerk/protocol/http/nsHttpDigestAuth.cpp