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 /* -*- 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/. */

 #include "nsXPIDLString.h"

 #include "nsCOMPtr.h"

 #include "nsISupports.h"

 #include "nsIInterfaceRequestor.h"

 #include "nsCRT.h"

 #include "nsICMSSecureMessage.h"

 #include "nsCMSSecureMessage.h"

 #include "nsNSSCertificate.h"

 #include "nsNSSHelper.h"

 #include "nsNSSShutDown.h"

 #include <string.h>

 #include "plbase64.h"

 #include "cert.h"

 #include "cms.h"

 #include "nsIServiceManager.h"

 #include "nsIPrefService.h"

 #include "nsIPrefBranch.h"

 #include "prlog.h"

 #ifdef PR_LOGGING

 extern PRLogModuleInfo* gPIPNSSLog;

 #endif

 // Standard ISupports implementation

 // NOTE: Should these be the thread-safe versions?

 /*****

  * nsCMSSecureMessage

  *****/

 // Standard ISupports implementation

 NS_IMPL_ISUPPORTS(nsCMSSecureMessage, nsICMSSecureMessage)

 // nsCMSSecureMessage constructor

 nsCMSSecureMessage::nsCMSSecureMessage()

 {

   // initialize superclass

 }

 // nsCMSMessage destructor

 nsCMSSecureMessage::~nsCMSSecureMessage()

 {

 }

 /* string getCertByPrefID (in string certID); */

 NS_IMETHODIMP nsCMSSecureMessage::

 GetCertByPrefID(const char *certID, char **_retval)

 {

   nsNSSShutDownPreventionLock locker;

   PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::GetCertByPrefID\n"));

   nsresult rv = NS_OK;

   CERTCertificate *cert = 0;

   nsXPIDLCString nickname;

   nsCOMPtr<nsIInterfaceRequestor> ctx = new PipUIContext();

   *_retval = 0;

   nsCOMPtr<nsIPrefBranch> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID, &rv);

   if (NS_FAILED(rv)) {

     goto done;

   }

   rv = prefs->GetCharPref(certID,

                           getter_Copies(nickname));

   if (NS_FAILED(rv)) goto done;

   /* Find a good cert in the user's database */

   cert = CERT_FindUserCertByUsage(CERT_GetDefaultCertDB(), const_cast<char*>(nickname.get()), 

            certUsageEmailRecipient, true, ctx);

   if (!cert) { 

     /* Success, but no value */

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::GetCertByPrefID - can't find user cert\n"));

     goto done;

   } 

   /* Convert the DER to a BASE64 String */

   encode(cert->derCert.data, cert->derCert.len, _retval);

 done:

   if (cert) CERT_DestroyCertificate(cert);

   return rv;

 }

 // nsCMSSecureMessage::DecodeCert

 nsresult nsCMSSecureMessage::

 DecodeCert(const char *value, nsIX509Cert ** _retval)

 {

   nsNSSShutDownPreventionLock locker;

   PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::DecodeCert\n"));

   nsresult rv = NS_OK;

   int32_t length;

   unsigned char *data = 0;

   *_retval = 0;

   if (!value) { return NS_ERROR_FAILURE; }

   rv = decode(value, &data, &length);

   if (NS_FAILED(rv)) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::DecodeCert - can't decode cert\n"));

     return rv;

   }

   nsCOMPtr<nsIX509Cert> cert =  nsNSSCertificate::ConstructFromDER((char *)data, length);

   if (cert) {

     *_retval = cert;

     NS_ADDREF(*_retval);

   }

   else {

     rv = NS_ERROR_FAILURE;

   }

   free((char*)data);

   return rv;

 }

 // nsCMSSecureMessage::SendMessage

 nsresult nsCMSSecureMessage::

 SendMessage(const char *msg, const char *base64Cert, char ** _retval)

 {

   nsNSSShutDownPreventionLock locker;

   PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::SendMessage\n"));

   nsresult rv = NS_OK;

   CERTCertificate *cert = 0;

   NSSCMSMessage *cmsMsg = 0;

   unsigned char *certDER = 0;

   int32_t derLen;

   NSSCMSEnvelopedData *env;

   NSSCMSContentInfo *cinfo;

   NSSCMSRecipientInfo *rcpt;

   SECItem output;

   PLArenaPool *arena = PORT_NewArena(1024);

   SECStatus s;

   nsCOMPtr<nsIInterfaceRequestor> ctx = new PipUIContext();

   /* Step 0. Create a CMS Message */

   cmsMsg = NSS_CMSMessage_Create(nullptr);

   if (!cmsMsg) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::SendMessage - can't create NSSCMSMessage\n"));

     rv = NS_ERROR_FAILURE;

     goto done;

   }

   /* Step 1.  Import the certificate into NSS */

   rv = decode(base64Cert, &certDER, &derLen);

   if (NS_FAILED(rv)) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::SendMessage - can't decode / import cert into NSS\n"));

     goto done;

   }

   cert = CERT_DecodeCertFromPackage((char *)certDER, derLen);

   if (!cert) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::SendMessage - can't decode cert from package\n"));

     rv = NS_ERROR_FAILURE;

     goto done;

   }

   /* Step 2.  Get a signature cert */

   /* Step 3. Build inner (signature) content */

   /* Step 4. Build outer (enveloped) content */

   env = NSS_CMSEnvelopedData_Create(cmsMsg, SEC_OID_DES_EDE3_CBC, 0);

   if (!env) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::SendMessage - can't create envelope data\n"));

     rv = NS_ERROR_FAILURE;

     goto done;

   }

   cinfo = NSS_CMSEnvelopedData_GetContentInfo(env);

   s = NSS_CMSContentInfo_SetContent_Data(cmsMsg, cinfo, 0, false);

   if (s != SECSuccess) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::SendMessage - can't set content data\n"));

     rv = NS_ERROR_FAILURE;

     goto done;

   }

   rcpt = NSS_CMSRecipientInfo_Create(cmsMsg, cert);

   if (!rcpt) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::SendMessage - can't create recipient info\n"));

     rv = NS_ERROR_FAILURE;

     goto done;

   }

   s = NSS_CMSEnvelopedData_AddRecipient(env, rcpt);

   if (s != SECSuccess) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::SendMessage - can't add recipient\n"));

     rv = NS_ERROR_FAILURE;

     goto done;

   }

   /* Step 5. Add content to message */

   cinfo = NSS_CMSMessage_GetContentInfo(cmsMsg);

   s = NSS_CMSContentInfo_SetContent_EnvelopedData(cmsMsg, cinfo, env);

   if (s != SECSuccess) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::SendMessage - can't set content enveloped data\n"));

     rv = NS_ERROR_FAILURE;

     goto done;

   }

   /* Step 6. Encode */

   NSSCMSEncoderContext *ecx;

   output.data = 0; output.len = 0;

   ecx = NSS_CMSEncoder_Start(cmsMsg, 0, 0, &output, arena,

             0, ctx, 0, 0, 0, 0);

   if (!ecx) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::SendMessage - can't start cms encoder\n"));

     rv = NS_ERROR_FAILURE;

     goto done;

   }

   s = NSS_CMSEncoder_Update(ecx, msg, strlen(msg));

   if (s != SECSuccess) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::SendMessage - can't update encoder\n"));

     rv = NS_ERROR_FAILURE;

     goto done;

   }

   s = NSS_CMSEncoder_Finish(ecx);

   if (s != SECSuccess) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::SendMessage - can't finish encoder\n"));

     rv = NS_ERROR_FAILURE;

     goto done;

   }

   /* Step 7. Base64 encode and return the result */

   rv = encode(output.data, output.len, _retval);

 done:

   if (certDER) free((char *)certDER);

   if (cert) CERT_DestroyCertificate(cert);

   if (cmsMsg) NSS_CMSMessage_Destroy(cmsMsg);

   if (arena) PORT_FreeArena(arena, false);  /* false? */

   return rv;

 }

 /*

  * nsCMSSecureMessage::ReceiveMessage

  */

 nsresult nsCMSSecureMessage::

 ReceiveMessage(const char *msg, char **_retval)

 {

   nsNSSShutDownPreventionLock locker;

   PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::ReceiveMessage\n"));

   nsresult rv = NS_OK;

   NSSCMSDecoderContext *dcx;

   unsigned char *der = 0;

   int32_t derLen;

   NSSCMSMessage *cmsMsg = 0;

   SECItem *content;

   nsCOMPtr<nsIInterfaceRequestor> ctx = new PipUIContext();

   /* Step 1. Decode the base64 wrapper */

   rv = decode(msg, &der, &derLen);

   if (NS_FAILED(rv)) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::ReceiveMessage - can't base64 decode\n"));

     goto done;

   }

   dcx = NSS_CMSDecoder_Start(0, 0, 0, /* pw */ 0, ctx, /* key */ 0, 0);

   if (!dcx) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::ReceiveMessage - can't start decoder\n"));

     rv = NS_ERROR_FAILURE;

     goto done;

   }

   (void)NSS_CMSDecoder_Update(dcx, (char *)der, derLen);

   cmsMsg = NSS_CMSDecoder_Finish(dcx);

   if (!cmsMsg) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::ReceiveMessage - can't finish decoder\n"));

     rv = NS_ERROR_FAILURE;

     /* Memory leak on dcx?? */

     goto done;

   }

   content = NSS_CMSMessage_GetContent(cmsMsg);

   if (!content) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::ReceiveMessage - can't get content\n"));

     rv = NS_ERROR_FAILURE;

     goto done;

   }

   /* Copy the data */

   *_retval = (char*)malloc(content->len+1);

   memcpy(*_retval, content->data, content->len);

   (*_retval)[content->len] = 0;

 done:

   if (der) free(der);

   if (cmsMsg) NSS_CMSMessage_Destroy(cmsMsg);

   return rv;

 }

 nsresult nsCMSSecureMessage::

 encode(const unsigned char *data, int32_t dataLen, char **_retval)

 {

   nsresult rv = NS_OK;

   *_retval = PL_Base64Encode((const char *)data, dataLen, nullptr);

   if (!*_retval) { rv = NS_ERROR_OUT_OF_MEMORY; goto loser; }

 loser:

   return rv;

 }

 nsresult nsCMSSecureMessage::

 decode(const char *data, unsigned char **result, int32_t * _retval)

 {

   PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::decode\n"));

   nsresult rv = NS_OK;

   uint32_t len = strlen(data);

   int adjust = 0;

   /* Compute length adjustment */

   if (data[len-1] == '=') {

     adjust++;

     if (data[len-2] == '=') adjust++;

   }

   *result = (unsigned char *)PL_Base64Decode(data, len, nullptr);

   if (!*result) {

     PR_LOG(gPIPNSSLog, PR_LOG_DEBUG, ("nsCMSSecureMessage::decode - error decoding base64\n"));

     rv = NS_ERROR_ILLEGAL_VALUE;

     goto loser;

   }

   *_retval = (len*3)/4 - adjust;

 loser:

   return rv;

 }