michael@0: /* vim:set ts=4 sw=4 et cindent: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "nsAuth.h"
michael@0: #include "nsAuthSambaNTLM.h"
michael@0: #include "prenv.h"
michael@0: #include "plbase64.h"
michael@0: #include "prerror.h"
michael@0: #include "mozilla/Telemetry.h"
michael@0: 
michael@0: #include <stdlib.h>
michael@0: 
michael@0: nsAuthSambaNTLM::nsAuthSambaNTLM()
michael@0:     : mInitialMessage(nullptr), mChildPID(nullptr), mFromChildFD(nullptr),
michael@0:       mToChildFD(nullptr)
michael@0: {
michael@0: }
michael@0: 
michael@0: nsAuthSambaNTLM::~nsAuthSambaNTLM()
michael@0: {
michael@0:     // ntlm_auth reads from stdin regularly so closing our file handles
michael@0:     // should cause it to exit.
michael@0:     Shutdown();
michael@0:     free(mInitialMessage);
michael@0: }
michael@0: 
michael@0: void
michael@0: nsAuthSambaNTLM::Shutdown()
michael@0: {
michael@0:     if (mFromChildFD) {
michael@0:         PR_Close(mFromChildFD);
michael@0:         mFromChildFD = nullptr;
michael@0:     }
michael@0:     if (mToChildFD) {
michael@0:         PR_Close(mToChildFD);
michael@0:         mToChildFD = nullptr;
michael@0:     }
michael@0:     if (mChildPID) {
michael@0:         int32_t exitCode;
michael@0:         PR_WaitProcess(mChildPID, &exitCode);
michael@0:         mChildPID = nullptr;
michael@0:     }
michael@0: }
michael@0: 
michael@0: NS_IMPL_ISUPPORTS(nsAuthSambaNTLM, nsIAuthModule)
michael@0: 
michael@0: static bool
michael@0: SpawnIOChild(char* const* aArgs, PRProcess** aPID,
michael@0:              PRFileDesc** aFromChildFD, PRFileDesc** aToChildFD)
michael@0: {
michael@0:     PRFileDesc* toChildPipeRead;
michael@0:     PRFileDesc* toChildPipeWrite;
michael@0:     if (PR_CreatePipe(&toChildPipeRead, &toChildPipeWrite) != PR_SUCCESS)
michael@0:         return false;
michael@0:     PR_SetFDInheritable(toChildPipeRead, true);
michael@0:     PR_SetFDInheritable(toChildPipeWrite, false);
michael@0: 
michael@0:     PRFileDesc* fromChildPipeRead;
michael@0:     PRFileDesc* fromChildPipeWrite;
michael@0:     if (PR_CreatePipe(&fromChildPipeRead, &fromChildPipeWrite) != PR_SUCCESS) {
michael@0:         PR_Close(toChildPipeRead);
michael@0:         PR_Close(toChildPipeWrite);
michael@0:         return false;
michael@0:     }
michael@0:     PR_SetFDInheritable(fromChildPipeRead, false);
michael@0:     PR_SetFDInheritable(fromChildPipeWrite, true);
michael@0: 
michael@0:     PRProcessAttr* attr = PR_NewProcessAttr();
michael@0:     if (!attr) {
michael@0:         PR_Close(fromChildPipeRead);
michael@0:         PR_Close(fromChildPipeWrite);
michael@0:         PR_Close(toChildPipeRead);
michael@0:         PR_Close(toChildPipeWrite);
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     PR_ProcessAttrSetStdioRedirect(attr, PR_StandardInput, toChildPipeRead);
michael@0:     PR_ProcessAttrSetStdioRedirect(attr, PR_StandardOutput, fromChildPipeWrite);   
michael@0: 
michael@0:     PRProcess* process = PR_CreateProcess(aArgs[0], aArgs, nullptr, attr);
michael@0:     PR_DestroyProcessAttr(attr);
michael@0:     PR_Close(fromChildPipeWrite);
michael@0:     PR_Close(toChildPipeRead);
michael@0:     if (!process) {
michael@0:         LOG(("ntlm_auth exec failure [%d]", PR_GetError()));
michael@0:         PR_Close(fromChildPipeRead);
michael@0:         PR_Close(toChildPipeWrite);
michael@0:         return false;        
michael@0:     }
michael@0: 
michael@0:     *aPID = process;
michael@0:     *aFromChildFD = fromChildPipeRead;
michael@0:     *aToChildFD = toChildPipeWrite;
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: static bool WriteString(PRFileDesc* aFD, const nsACString& aString)
michael@0: {
michael@0:     int32_t length = aString.Length();
michael@0:     const char* s = aString.BeginReading();
michael@0:     LOG(("Writing to ntlm_auth: %s", s));
michael@0: 
michael@0:     while (length > 0) {
michael@0:         int result = PR_Write(aFD, s, length);
michael@0:         if (result <= 0)
michael@0:             return false;
michael@0:         s += result;
michael@0:         length -= result;
michael@0:     }
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: static bool ReadLine(PRFileDesc* aFD, nsACString& aString)
michael@0: {
michael@0:     // ntlm_auth is defined to only send one line in response to each of our
michael@0:     // input lines. So this simple unbuffered strategy works as long as we
michael@0:     // read the response immediately after sending one request.
michael@0:     aString.Truncate();
michael@0:     for (;;) {
michael@0:         char buf[1024];
michael@0:         int result = PR_Read(aFD, buf, sizeof(buf));
michael@0:         if (result <= 0)
michael@0:             return false;
michael@0:         aString.Append(buf, result);
michael@0:         if (buf[result - 1] == '\n') {
michael@0:             LOG(("Read from ntlm_auth: %s", nsPromiseFlatCString(aString).get()));
michael@0:             return true;
michael@0:         }
michael@0:     }
michael@0: }
michael@0: 
michael@0: /**
michael@0:  * Returns a heap-allocated array of PRUint8s, and stores the length in aLen.
michael@0:  * Returns nullptr if there's an error of any kind.
michael@0:  */
michael@0: static uint8_t* ExtractMessage(const nsACString& aLine, uint32_t* aLen)
michael@0: {
michael@0:     // ntlm_auth sends blobs to us as base64-encoded strings after the "xx "
michael@0:     // preamble on the response line.
michael@0:     int32_t length = aLine.Length();
michael@0:     // The caller should verify there is a valid "xx " prefix and the line
michael@0:     // is terminated with a \n
michael@0:     NS_ASSERTION(length >= 4, "Line too short...");
michael@0:     const char* line = aLine.BeginReading();
michael@0:     const char* s = line + 3;
michael@0:     length -= 4; // lose first 3 chars plus trailing \n
michael@0:     NS_ASSERTION(s[length] == '\n', "aLine not newline-terminated");
michael@0:     
michael@0:     if (length & 3) {
michael@0:         // The base64 encoded block must be multiple of 4. If not, something
michael@0:         // screwed up.
michael@0:         NS_WARNING("Base64 encoded block should be a multiple of 4 chars");
michael@0:         return nullptr;
michael@0:     } 
michael@0: 
michael@0:     // Calculate the exact length. I wonder why there isn't a function for this
michael@0:     // in plbase64.
michael@0:     int32_t numEquals;
michael@0:     for (numEquals = 0; numEquals < length; ++numEquals) {
michael@0:         if (s[length - 1 - numEquals] != '=')
michael@0:             break;
michael@0:     }
michael@0:     *aLen = (length/4)*3 - numEquals;
michael@0:     return reinterpret_cast<uint8_t*>(PL_Base64Decode(s, length, nullptr));
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: nsAuthSambaNTLM::SpawnNTLMAuthHelper()
michael@0: {
michael@0:     const char* username = PR_GetEnv("USER");
michael@0:     if (!username)
michael@0:         return NS_ERROR_FAILURE;
michael@0: 
michael@0:     const char* const args[] = {
michael@0:         "ntlm_auth",
michael@0:         "--helper-protocol", "ntlmssp-client-1",
michael@0:         "--use-cached-creds",
michael@0:         "--username", username,
michael@0:         nullptr
michael@0:     };
michael@0: 
michael@0:     bool isOK = SpawnIOChild(const_cast<char* const*>(args), &mChildPID, &mFromChildFD, &mToChildFD);
michael@0:     if (!isOK)  
michael@0:         return NS_ERROR_FAILURE;
michael@0: 
michael@0:     if (!WriteString(mToChildFD, NS_LITERAL_CSTRING("YR\n")))
michael@0:         return NS_ERROR_FAILURE;
michael@0:     nsCString line;
michael@0:     if (!ReadLine(mFromChildFD, line))
michael@0:         return NS_ERROR_FAILURE;
michael@0:     if (!StringBeginsWith(line, NS_LITERAL_CSTRING("YR "))) {
michael@0:         // Something went wrong. Perhaps no credentials are accessible.
michael@0:         return NS_ERROR_FAILURE;
michael@0:     }
michael@0: 
michael@0:     // It gave us an initial client-to-server request packet. Save that
michael@0:     // because we'll need it later.
michael@0:     mInitialMessage = ExtractMessage(line, &mInitialMessageLen);
michael@0:     if (!mInitialMessage)
michael@0:         return NS_ERROR_FAILURE;
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsAuthSambaNTLM::Init(const char *serviceName,
michael@0:                       uint32_t    serviceFlags,
michael@0:                       const char16_t *domain,
michael@0:                       const char16_t *username,
michael@0:                       const char16_t *password)
michael@0: {
michael@0:     NS_ASSERTION(!username && !domain && !password, "unexpected credentials");
michael@0: 
michael@0:     static bool sTelemetrySent = false;
michael@0:     if (!sTelemetrySent) {
michael@0:         mozilla::Telemetry::Accumulate(
michael@0:             mozilla::Telemetry::NTLM_MODULE_USED_2,
michael@0:             serviceFlags & nsIAuthModule::REQ_PROXY_AUTH
michael@0:                 ? NTLM_MODULE_SAMBA_AUTH_PROXY
michael@0:                 : NTLM_MODULE_SAMBA_AUTH_DIRECT);
michael@0:         sTelemetrySent = true;
michael@0:     }
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsAuthSambaNTLM::GetNextToken(const void *inToken,
michael@0:                               uint32_t    inTokenLen,
michael@0:                               void      **outToken,
michael@0:                               uint32_t   *outTokenLen)
michael@0: {
michael@0:     if (!inToken) {
michael@0:         /* someone wants our initial message */
michael@0:         *outToken = nsMemory::Clone(mInitialMessage, mInitialMessageLen);
michael@0:         if (!*outToken)
michael@0:             return NS_ERROR_OUT_OF_MEMORY;
michael@0:         *outTokenLen = mInitialMessageLen;
michael@0:         return NS_OK;
michael@0:     }
michael@0: 
michael@0:     /* inToken must be a type 2 message. Get ntlm_auth to generate our response */
michael@0:     char* encoded = PL_Base64Encode(static_cast<const char*>(inToken), inTokenLen, nullptr);
michael@0:     if (!encoded)
michael@0:         return NS_ERROR_OUT_OF_MEMORY;
michael@0: 
michael@0:     nsCString request;
michael@0:     request.AssignLiteral("TT ");
michael@0:     request.Append(encoded);
michael@0:     free(encoded);
michael@0:     request.Append('\n');
michael@0: 
michael@0:     if (!WriteString(mToChildFD, request))
michael@0:         return NS_ERROR_FAILURE;
michael@0:     nsCString line;
michael@0:     if (!ReadLine(mFromChildFD, line))
michael@0:         return NS_ERROR_FAILURE;
michael@0:     if (!StringBeginsWith(line, NS_LITERAL_CSTRING("KK "))) {
michael@0:         // Something went wrong. Perhaps no credentials are accessible.
michael@0:         return NS_ERROR_FAILURE;
michael@0:     }
michael@0:     uint8_t* buf = ExtractMessage(line, outTokenLen);
michael@0:     if (!buf)
michael@0:         return NS_ERROR_FAILURE;
michael@0:     // *outToken has to be freed by nsMemory::Free, which may not be free() 
michael@0:     *outToken = nsMemory::Clone(buf, *outTokenLen);
michael@0:     if (!*outToken) {
michael@0:         free(buf);
michael@0:         return NS_ERROR_OUT_OF_MEMORY;
michael@0:     }
michael@0:     
michael@0:     // We're done. Close our file descriptors now and reap the helper
michael@0:     // process.
michael@0:     Shutdown();
michael@0:     return NS_SUCCESS_AUTH_FINISHED;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsAuthSambaNTLM::Unwrap(const void *inToken,
michael@0:                         uint32_t    inTokenLen,
michael@0:                         void      **outToken,
michael@0:                         uint32_t   *outTokenLen)
michael@0: {
michael@0:     return NS_ERROR_NOT_IMPLEMENTED;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsAuthSambaNTLM::Wrap(const void *inToken,
michael@0:                       uint32_t    inTokenLen,
michael@0:                       bool        confidential,
michael@0:                       void      **outToken,
michael@0:                       uint32_t   *outTokenLen)
michael@0: {
michael@0:     return NS_ERROR_NOT_IMPLEMENTED;
michael@0: }