1 files changed, 112 insertions, 7 deletions

diff --git a/linden/indra/llmessage/llxfermanager.cpp b/linden/indra/llmessage/llxfermanager.cpp
index f40612c..8173b7c 100644
--- a/linden/indra/llmessage/llxfermanager.cpp
+++ b/linden/indra/llmessage/llxfermanager.cpp
@@ -713,6 +713,78 @@ void LLXferManager::sendConfirmPacket (LLMessageSystem *mesgsys, U64 id, S32 pac
 
 ///////////////////////////////////////////////////////////
 
+static bool find_and_remove(std::multiset<std::string>& files,
+                const std::string& filename)
+{
+        std::multiset<std::string>::iterator ptr;
+        if ( (ptr = files.find(filename)) != files.end())
+        {
+                //erase(filename) erases *all* entries with that key
+                files.erase(ptr);
+                return true;
+        }
+        return false;
+}
+
+void LLXferManager::expectFileForRequest(const std::string& filename)
+{
+        mExpectedRequests.insert(filename);
+}
+
+bool LLXferManager::validateFileForRequest(const std::string& filename)
+{
+        return find_and_remove(mExpectedRequests, filename);
+}
+
+void LLXferManager::expectFileForTransfer(const std::string& filename)
+{
+        mExpectedTransfers.insert(filename);
+}
+
+bool LLXferManager::validateFileForTransfer(const std::string& filename)
+{
+        return find_and_remove(mExpectedTransfers, filename);
+}
+
+static bool remove_prefix(std::string& filename, const std::string& prefix)
+{
+        if (std::equal(prefix.begin(), prefix.end(), filename.begin()))
+        {
+                filename = filename.substr(prefix.length());
+                return true;
+        }
+        return false;
+}
+
+static bool verify_cache_filename(const std::string& filename)
+{
+        //NOTE: This routine is only used to check file names that our own
+        // code places in the cache directory.  As such, it can be limited
+        // to this very restrictive file name pattern.  It does not need to
+        // handle other characters.
+
+        size_t len = filename.size();
+        //const boost::regex expr("[a-zA-Z0-9][-_.a-zA-Z0-9]<0,49>");
+        if (len < 1 || len > 50)
+        {
+                return false;
+        }
+        for(unsigned i=0; i<len; ++i)
+        {
+                char c = filename[i];
+                bool ok = isalnum(c);
+                if (!ok && i > 0)
+                {
+                        ok = '_'==c || '-'==c || '.'==c;
+                }
+                if (!ok)
+                {
+                        return false;
+                }
+        }
+        return true;
+}
+
 void LLXferManager::processFileRequest (LLMessageSystem *mesgsys, void ** /*user_data*/)
 {
                 
@@ -734,16 +806,11 @@ void LLXferManager::processFileRequest (LLMessageSystem *mesgsys, void ** /*user
 
         mesgsys->getStringFast(_PREHASH_XferID, _PREHASH_Filename, local_filename);
         
-        U8 local_path_u8;
-        mesgsys->getU8("XferID", "FilePath", local_path_u8);
-        if( local_path_u8 < (U8)LL_PATH_LAST )
         {
+                U8 local_path_u8;
+                mesgsys->getU8("XferID", "FilePath", local_path_u8);
                 local_path = (ELLPath)local_path_u8;
         }
-        else
-        {
-                llwarns << "Invalid file path in LLXferManager::processFileRequest() " << (U32)local_path_u8 << llendl;
-        }
 
         mesgsys->getUUIDFast(_PREHASH_XferID, _PREHASH_VFileID, uuid);
         mesgsys->getS16Fast(_PREHASH_XferID, _PREHASH_VFileType, type_s16);
@@ -782,6 +849,43 @@ void LLXferManager::processFileRequest (LLMessageSystem *mesgsys, void ** /*user
         }
         else if (!local_filename.empty())
         {
+                // See DEV-21775 for detailed security issues
+
+                if (local_path == LL_PATH_NONE)
+                {
+                        // this handles legacy simulators that are passing objects
+                        // by giving a filename that explicitly names the cache directory
+                        static const std::string legacy_cache_prefix = "data/";
+                        if (remove_prefix(local_filename, legacy_cache_prefix))
+                        {
+                                local_path = LL_PATH_CACHE;
+                        }
+                }
+
+                switch (local_path)
+                {
+                        case LL_PATH_NONE:
+                                if(!validateFileForTransfer(local_filename))
+                                {
+                                        llwarns << "SECURITY: Unapproved filename '" << local_filename << llendl;
+                                        return;
+                                }
+                                break;
+
+                        case LL_PATH_CACHE:
+                                if(!verify_cache_filename(local_filename))
+                                {
+                                        llwarns << "SECURITY: Illegal cache filename '" << local_filename << llendl;
+                                        return;
+                                }
+                                break;
+
+                        default:
+                                llwarns << "SECURITY: Restricted file dir enum: " << (U32)local_path << llendl;
+                                return;
+                }
+
+
                 std::string expanded_filename = gDirUtilp->getExpandedFilename( local_path, local_filename );
                 llinfos << "starting file transfer: " <<  expanded_filename << " to " << mesgsys->getSender() << llendl;
 
@@ -861,6 +965,7 @@ void LLXferManager::processFileRequest (LLMessageSystem *mesgsys, void ** /*user
         }
 }
 
+
 ///////////////////////////////////////////////////////////
 
 void LLXferManager::processConfirmation (LLMessageSystem *mesgsys, void ** /*user_data*/)