diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 1e45146e1..19d21193c 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -105,7 +105,7 @@ jobs:
     container: ${{ matrix.container }}
     strategy:
       matrix:
-        container: ['ubuntu:20.04', 'ubuntu:22.04', 'ubuntu:23.04', 'ubuntu:23.10']
+        container: ['ubuntu:20.04', 'ubuntu:22.04', 'ubuntu:23.10']
     env:
       DEBIAN_FRONTEND: noninteractive
       DEBFULLNAME: github-actions
diff --git a/examples/DigiDocCSharp/DigiDocCSharp.csproj b/examples/DigiDocCSharp/DigiDocCSharp.csproj
index 9ed490dbe..39be3b098 100644
--- a/examples/DigiDocCSharp/DigiDocCSharp.csproj
+++ b/examples/DigiDocCSharp/DigiDocCSharp.csproj
@@ -2,7 +2,7 @@
 <Project ToolsVersion="4.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <PropertyGroup>
     <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
-    <Platform Condition=" '$(Platform)' == '' ">x86</Platform>
+    <Platform Condition=" '$(Platform)' == '' ">x64</Platform>
     <ProductVersion>8.0.30703</ProductVersion>
     <SchemaVersion>2.0</SchemaVersion>
     <ProjectGuid>{DDEE2029-EA2A-49D2-80CB-F0E2E396B005}</ProjectGuid>
@@ -10,12 +10,11 @@
     <AppDesignerFolder>Properties</AppDesignerFolder>
     <RootNamespace>DigiDocCSharp</RootNamespace>
     <AssemblyName>DigiDocCSharp</AssemblyName>
-    <TargetFrameworkVersion>v4.0</TargetFrameworkVersion>
-    <TargetFrameworkProfile>Client</TargetFrameworkProfile>
+    <TargetFrameworkVersion>v4.7.2</TargetFrameworkVersion>
     <FileAlignment>512</FileAlignment>
   </PropertyGroup>
-  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|x86' ">
-    <PlatformTarget>x86</PlatformTarget>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|x64' ">
+    <PlatformTarget>x64</PlatformTarget>
     <DebugSymbols>true</DebugSymbols>
     <DebugType>full</DebugType>
     <Optimize>false</Optimize>
@@ -25,8 +24,8 @@
     <WarningLevel>4</WarningLevel>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
   </PropertyGroup>
-  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|x86' ">
-    <PlatformTarget>x86</PlatformTarget>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|x64' ">
+    <PlatformTarget>x64</PlatformTarget>
     <DebugType>pdbonly</DebugType>
     <Optimize>true</Optimize>
     <OutputPath>bin\Release\</OutputPath>
diff --git a/examples/DigiDocCSharp/DigiDocCSharp.sln b/examples/DigiDocCSharp/DigiDocCSharp.sln
index 7cdf7b5e2..c599b3085 100644
--- a/examples/DigiDocCSharp/DigiDocCSharp.sln
+++ b/examples/DigiDocCSharp/DigiDocCSharp.sln
@@ -5,14 +5,14 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "DigiDocCSharp", "DigiDocCSh
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
-		Debug|x86 = Debug|x86
-		Release|x86 = Release|x86
+		Debug|x64 = Debug|x64
+		Release|x64 = Release|x64
 	EndGlobalSection
 	GlobalSection(ProjectConfigurationPlatforms) = postSolution
-		{DDEE2029-EA2A-49D2-80CB-F0E2E396B005}.Debug|x86.ActiveCfg = Debug|x86
-		{DDEE2029-EA2A-49D2-80CB-F0E2E396B005}.Debug|x86.Build.0 = Debug|x86
-		{DDEE2029-EA2A-49D2-80CB-F0E2E396B005}.Release|x86.ActiveCfg = Release|x86
-		{DDEE2029-EA2A-49D2-80CB-F0E2E396B005}.Release|x86.Build.0 = Release|x86
+		{DDEE2029-EA2A-49D2-80CB-F0E2E396B005}.Debug|x64.ActiveCfg = Debug|x64
+		{DDEE2029-EA2A-49D2-80CB-F0E2E396B005}.Debug|x64.Build.0 = Debug|x64
+		{DDEE2029-EA2A-49D2-80CB-F0E2E396B005}.Release|x64.ActiveCfg = Release|x64
+		{DDEE2029-EA2A-49D2-80CB-F0E2E396B005}.Release|x64.Build.0 = Release|x64
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
diff --git a/examples/DigiDocCSharp/Program.cs b/examples/DigiDocCSharp/Program.cs
index 731d69af5..4e0dab4b9 100644
--- a/examples/DigiDocCSharp/Program.cs
+++ b/examples/DigiDocCSharp/Program.cs
@@ -184,7 +184,8 @@ private static void Verify(string file)
             try
             {
                 Console.WriteLine("Opening file: " + file);
-                Container b = Container.open(file);
+                var cb = new ContainerOpen();
+                Container b = Container.open(file, cb);
 
                 Console.WriteLine("Files:");
                 foreach (DataFile d in b.dataFiles())
@@ -226,4 +227,9 @@ private static void Version()
                 " libdigidocpp " + digidoc.digidoc.version());
         }
     }
+
+    class ContainerOpen : ContainerOpenCB 
+    {
+        override public bool validateOnline() { return true; }
+    }
 }
diff --git a/examples/java/README.md b/examples/java/README.md
index 0aeebec8f..62857a779 100644
--- a/examples/java/README.md
+++ b/examples/java/README.md
@@ -6,4 +6,4 @@
 
 ## Run
 
-    java -Djava.library.path=/Library/libdigidocpp/lib -jar build/libs/libdigidoc.jar
\ No newline at end of file
+    java -Djava.library.path=/some/path/lib -jar build/libs/libdigidoc.jar
\ No newline at end of file
diff --git a/examples/java/gradle/wrapper/gradle-wrapper.jar b/examples/java/gradle/wrapper/gradle-wrapper.jar
index ccebba771..7f93135c4 100644
Binary files a/examples/java/gradle/wrapper/gradle-wrapper.jar and b/examples/java/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/examples/java/gradle/wrapper/gradle-wrapper.properties b/examples/java/gradle/wrapper/gradle-wrapper.properties
index c30b486a8..3fa8f862f 100644
--- a/examples/java/gradle/wrapper/gradle-wrapper.properties
+++ b/examples/java/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,7 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.3-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.4-bin.zip
 networkTimeout=10000
+validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
diff --git a/examples/java/gradlew b/examples/java/gradlew
index 79a61d421..0adc8e1a5 100755
--- a/examples/java/gradlew
+++ b/examples/java/gradlew
@@ -83,10 +83,8 @@ done
 # This is normally unused
 # shellcheck disable=SC2034
 APP_BASE_NAME=${0##*/}
-APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
-
-# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
-DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+# Discard cd standard output in case $CDPATH is set (https://github.com/gradle/gradle/issues/25036)
+APP_HOME=$( cd "${APP_HOME:-./}" > /dev/null && pwd -P ) || exit
 
 # Use the maximum available, or set MAX_FD != -1 to use that value.
 MAX_FD=maximum
@@ -133,10 +131,13 @@ location of your Java installation."
     fi
 else
     JAVACMD=java
-    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+    if ! command -v java >/dev/null 2>&1
+    then
+        die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
 
 Please set the JAVA_HOME variable in your environment to match the
 location of your Java installation."
+    fi
 fi
 
 # Increase the maximum file descriptors if we can.
@@ -197,6 +198,10 @@ if "$cygwin" || "$msys" ; then
     done
 fi
 
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
 # Collect all arguments for the java command;
 #   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
 #     shell script including quotes and variable substitutions, so put them in
diff --git a/examples/java/src/main/java/ee/ria/libdigidocpp/libdigidocpp.java b/examples/java/src/main/java/ee/ria/libdigidocpp/libdigidocpp.java
index 5fdabd498..5ff995e76 100644
--- a/examples/java/src/main/java/ee/ria/libdigidocpp/libdigidocpp.java
+++ b/examples/java/src/main/java/ee/ria/libdigidocpp/libdigidocpp.java
@@ -133,7 +133,8 @@ static void verify(String file) {
         try
         {
             System.out.println("Opening file: " + file);
-            Container b = Container.open(file);
+            ContainerOpen cb = new ContainerOpen();
+            Container b = Container.open(file, cb);
             assert b != null;
 
             System.out.println("Files:");
@@ -200,4 +201,10 @@ static byte[] fromHex(String s) {
         }
         return data;
     }
+
+    static private class ContainerOpen extends ContainerOpenCB
+    {
+        @Override
+        public boolean validateOnline() { return true; }
+    }
 }
diff --git a/examples/python/main.py b/examples/python/main.py
index 05e4249bb..68e687eaf 100644
--- a/examples/python/main.py
+++ b/examples/python/main.py
@@ -2,6 +2,13 @@
 import sys
 import os
 
+class ContainerOpenCB(digidoc.ContainerOpenCB):
+
+    def __init__(self):
+        digidoc.ContainerOpenCB.__init__(self)
+
+    def validateOnline(self):
+        return True
 
 class Program:
     digidoc.initialize()
@@ -78,7 +85,8 @@ def sign(self, args):
 
     def verify(self, file):
         print("Opening file: " + file)
-        doc = digidoc.Container.open(file)
+        cb = ContainerOpenCB()
+        doc = digidoc.Container.open(file, cb)
 
         print("Files:")
         for d in doc.dataFiles():
diff --git a/libdigidocpp.dox b/libdigidocpp.dox
index 9375cb6d5..031ec80f1 100644
--- a/libdigidocpp.dox
+++ b/libdigidocpp.dox
@@ -1380,6 +1380,8 @@ Signature Validation Policy
 Default POLv2
 
 http://open-eid.github.io/SiVa/siva/appendix/validation_policy/</td></tr>
+<tr><td>\-\-offline	</td><td>Optional</td><td>
+open container offline (eg. Don't send to SiVa)</td></tr>
 <tr><td>\-\-warnings=
 
 (ignore, warning, error)	</td><td>Optional</td><td>
diff --git a/libdigidocpp.i b/libdigidocpp.i
index f265c3322..f64ba3ee0 100644
--- a/libdigidocpp.i
+++ b/libdigidocpp.i
@@ -19,7 +19,7 @@
 
 // digidocpp.i - SWIG interface for libdigidocpp library
 
-%module digidoc
+%module(directors="1") digidoc
 
 %begin %{
 #ifdef _MSC_VER
@@ -231,6 +231,8 @@ extern "C"
 %newobject digidoc::Container::open;
 %newobject digidoc::Container::create;
 
+%feature("director") digidoc::ContainerOpenCB;
+
 %typemap(javacode) digidoc::Conf %{
   public Conf transfer() {
     swigCMemOwn = false;
@@ -318,16 +320,21 @@ namespace std {
     }
 }
 %extend digidoc::Container {
+    static digidoc::Container* open(const std::string &path, digidoc::ContainerOpenCB *cb)
+    {
+        return digidoc::Container::openPtr(path, cb).release();
+    }
+
     digidoc::Signature* prepareWebSignature(const std::vector<unsigned char> &cert, const std::string &profile = {},
                                    const std::vector<std::string> &roles = {},
                                    const std::string &city = {}, const std::string &state = {},
                                    const std::string &postalCode = {}, const std::string &country = {})
     {
-        class : public digidoc::Signer
+        class final: public digidoc::Signer
         {
         public:
-            digidoc::X509Cert cert() const override { return _cert; }
-            std::vector<unsigned char> sign(const std::string &, const std::vector<unsigned char> &) const override
+            digidoc::X509Cert cert() const final { return _cert; }
+            std::vector<unsigned char> sign(const std::string &, const std::vector<unsigned char> &) const final
             {
                 THROW("Not implemented");
             }
diff --git a/src/ASiC_S.cpp b/src/ASiC_S.cpp
index f7c7e6fec..15e0d2151 100644
--- a/src/ASiC_S.cpp
+++ b/src/ASiC_S.cpp
@@ -102,7 +102,7 @@ void ASiC_S::addAdESSignature(istream & /*signature*/)
     THROW("Not implemented.");
 }
 
-unique_ptr<Container> ASiC_S::openInternal(const string &path)
+unique_ptr<Container> ASiC_S::openInternal(const string &path, ContainerOpenCB * /*cb*/)
 {
     if (!isContainerSimpleFormat(path))
         return {};
diff --git a/src/ASiC_S.h b/src/ASiC_S.h
index 95c9483ef..3af245268 100644
--- a/src/ASiC_S.h
+++ b/src/ASiC_S.h
@@ -41,7 +41,7 @@ namespace digidoc
         Signature* sign(Signer* signer) override;
 
         static std::unique_ptr<Container> createInternal(const std::string &path);
-        static std::unique_ptr<Container> openInternal(const std::string &path);
+        static std::unique_ptr<Container> openInternal(const std::string &path, ContainerOpenCB *cb);
 
     private:
         ASiC_S();
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index c55e19fb4..0d257c71a 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -271,13 +271,11 @@ if(SWIG_FOUND)
         target_include_directories(digidoc_java PRIVATE ${JAVA_INCLUDE_PATH} $<$<BOOL:${JAVA_INCLUDE_PATH2}>:${JAVA_INCLUDE_PATH2}>)
         target_compile_definitions(digidoc_java PRIVATE TARGET_NAME="$<TARGET_NAME:digidoc_java>")
         target_link_libraries(digidoc_java digidocpp digidocpp_util digidocpp_ver)
-        set_property(TARGET digidoc_java PROPERTY SWIG_COMPILE_DEFINITIONS $<$<PLATFORM_ID:Windows>:SWIGWIN>)
-        if(APPLE)
-            set_target_properties(digidoc_java PROPERTIES MACOSX_RPATH YES INSTALL_RPATH /Library/Frameworks)
-            install(TARGETS digidoc_java DESTINATION /Library/Java/Extensions)
-        else()
-            install(TARGETS digidoc_java DESTINATION ${CMAKE_INSTALL_LIBDIR})
-        endif()
+        set_target_properties(digidoc_java PROPERTIES
+            INSTALL_RPATH $<$<PLATFORM_ID:Darwin>:/Library/Frameworks>
+            SWIG_COMPILE_DEFINITIONS $<$<PLATFORM_ID:Windows>:SWIGWIN>
+        )
+        install(TARGETS digidoc_java DESTINATION $<IF:$<PLATFORM_ID:Darwin>,/Library/Java/Extensions,${CMAKE_INSTALL_LIBDIR}>)
         install(DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/java/ DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/ee/ria/libdigidocpp FILES_MATCHING PATTERN "*.java")
         if(WIN32)
             install(FILES $<TARGET_PDB_FILE:digidoc_java> DESTINATION ${CMAKE_INSTALL_BINDIR} OPTIONAL)
@@ -289,7 +287,6 @@ if(SWIG_FOUND)
         swig_add_library(digidoc_python LANGUAGE python SOURCES ../libdigidocpp.i)
         target_compile_definitions(digidoc_python PRIVATE TARGET_NAME="$<TARGET_NAME:digidoc_python>")
         target_link_libraries(digidoc_python digidocpp digidocpp_util digidocpp_ver Python3::Module)
-        set_property(TARGET digidoc_python PROPERTY SWIG_COMPILE_DEFINITIONS $<$<PLATFORM_ID:Windows>:SWIGWIN>)
         #configure_file(setup.py.cmake setup.py)
         #install(CODE "execute_process(COMMAND python3 ${CMAKE_CURRENT_BINARY_DIR}/setup.py install)")
         if(NOT Python3_SITELIB)
@@ -303,6 +300,10 @@ if(SWIG_FOUND)
         else()
             set_target_properties(digidoc_python PROPERTIES SUFFIX .so)
         endif()
+        set_target_properties(digidoc_python PROPERTIES
+            INSTALL_RPATH $<$<PLATFORM_ID:Darwin>:/Library/Frameworks>
+            SWIG_COMPILE_DEFINITIONS $<$<PLATFORM_ID:Windows>:SWIGWIN>
+        )
         install(TARGETS digidoc_python DESTINATION ${Python3_SITELIB})
         install(FILES ${CMAKE_CURRENT_BINARY_DIR}/digidoc.py DESTINATION ${Python3_SITELIB})
     endif()
diff --git a/src/Container.cpp b/src/Container.cpp
index d8bca3069..8592a5d35 100644
--- a/src/Container.cpp
+++ b/src/Container.cpp
@@ -68,7 +68,8 @@ namespace digidoc
 static string m_appName = "libdigidocpp";
 static string m_userAgent = "libdigidocpp";
 static vector<decltype(&Container::createPtr)> m_createList {};
-static vector<decltype(&Container::openPtr)> m_openList {};
+using OpenCB = std::unique_ptr<Container> (*)(const std::string &path, ContainerOpenCB *cb);
+static vector<OpenCB> m_openList {};
 }
 
 /**
@@ -96,14 +97,7 @@ string digidoc::userAgent() { return m_userAgent; }
  * Returns libdigidocpp library version
  */
 string digidoc::version() {
-    string ver = FILE_VER_STR;
-#if defined(DYNAMIC_LIBDIGIDOC) || defined(LINKED_LIBDIGIDOC)
-    ver += "_ddoc";
-#endif
-#ifdef PDF_SUPPORT
-    ver += "_siva";
-#endif
-    return ver;
+    return FILE_VER_STR;
 }
 
 /**
@@ -348,10 +342,22 @@ Container* Container::open(const string &path)
  * @throws Exception
  */
 unique_ptr<Container> Container::openPtr(const string &path)
+{
+    return openPtr(path, {});
+}
+
+/**
+ * Opens container from a file
+ *
+ * @param path
+ * @param cb Callback called when needed
+ * @throws Exception
+ */
+unique_ptr<Container> Container::openPtr(const string &path, ContainerOpenCB *cb)
 {
     for(auto open: m_openList)
     {
-        if(unique_ptr<Container> container = open(path))
+        if(unique_ptr<Container> container = open(path, cb))
             return container;
     }
     return ASiC_E::openInternal(path);
@@ -417,7 +423,7 @@ unique_ptr<Container> Container::openPtr(const string &path)
  *
  * It must contain static members:
  * * static Container* createInternal(const std::string &path);
- * * static Container* openInternal(const std::string &path);
+ * * static Container* openInternal(const std::string &path, digidoc::ContainerOpenCB *cb);
  *
  * @see Container::create, Container::open
  */
diff --git a/src/Container.h b/src/Container.h
index c2f9ac6d7..92655e978 100644
--- a/src/Container.h
+++ b/src/Container.h
@@ -40,6 +40,11 @@ DIGIDOCPP_EXPORT void terminate();
 DIGIDOCPP_EXPORT std::string userAgent();
 DIGIDOCPP_EXPORT std::string version();
 
+struct ContainerOpenCB {
+    virtual ~ContainerOpenCB() = default;
+    virtual bool validateOnline() const { return true; }
+};
+
 class DIGIDOCPP_EXPORT Container
 {
 public:
@@ -66,6 +71,7 @@ class DIGIDOCPP_EXPORT Container
     static std::unique_ptr<Container> createPtr(const std::string &path);
     DIGIDOCPP_DEPRECATED static Container* open(const std::string &path);
     static std::unique_ptr<Container> openPtr(const std::string &path);
+    static std::unique_ptr<Container> openPtr(const std::string &path, digidoc::ContainerOpenCB *cb);
     template<class T>
     static void addContainerImplementation();
 
diff --git a/src/SiVaContainer.cpp b/src/SiVaContainer.cpp
index 180612146..efafa5494 100644
--- a/src/SiVaContainer.cpp
+++ b/src/SiVaContainer.cpp
@@ -144,15 +144,14 @@ void SignatureSiVa::validate(const string &policy) const
 }
 
 
-SiVaContainer::SiVaContainer(const string &path, bool useHashCode)
+SiVaContainer::SiVaContainer(const string &path, ContainerOpenCB *cb, bool useHashCode)
     : d(make_unique<Private>())
 {
-    string ext = File::fileExtension(path);
-    DEBUG("SiVaContainer::SiVaContainer(%s, %s, %d)", path.c_str(), ext.c_str(), useHashCode);
+    DEBUG("SiVaContainer::SiVaContainer(%s, %d)", path.c_str(), useHashCode);
     unique_ptr<istream> ifs = make_unique<ifstream>(File::encodeName(d->path = path), ifstream::binary);
     auto fileName = File::fileName(path);
+    auto ext = File::fileExtension(path);
     istream *is = ifs.get();
-    static const array asic {"asice", "sce", "asics", "scs"};
     if(ext == "ddoc")
     {
         d->mediaType = "application/x-ddoc";
@@ -165,8 +164,10 @@ SiVaContainer::SiVaContainer(const string &path, bool useHashCode)
         d->mediaType = "application/pdf";
         d->dataFiles.push_back(new DataFilePrivate(std::move(ifs), fileName, "application/pdf"));
     }
-    else if(find(asic.cbegin(), asic.cend(), ext) != asic.cend())
+    else if(static const array asic {"asice", "sce", "asics", "scs"};
+        find(asic.cbegin(), asic.cend(), ext) != asic.cend())
     {
+        static const string_view metaInf = "META-INF/";
         ZipSerialize z(path, false);
         vector<string> list = z.list();
         if(list.empty() || list.front() != "mimetype")
@@ -174,13 +175,16 @@ SiVaContainer::SiVaContainer(const string &path, bool useHashCode)
         if(d->mediaType = ASiContainer::readMimetype(z);
             d->mediaType != ASiContainer::MIMETYPE_ASIC_E && d->mediaType != ASiContainer::MIMETYPE_ASIC_S)
             THROW("Unknown file");
-        if(none_of(list.cbegin(), list.cend(), [](const string &file) { return file.find("p7s") != string::npos; }))
+        if(static const string_view suffix = "META-INF/";
+            none_of(list.cbegin(), list.cend(), [](const string &file) {
+                auto index = file.size() - suffix.size();
+                return file.size() > suffix.size() && file.rfind(metaInf, 0) == 0 && file.find(suffix, index) == index;
+            }))
             THROW("Unknown file");
 
-        static const string metaInf = "META-INF/";
         for(const string &file: list)
         {
-            if(file == "mimetype" || file.substr(0, metaInf.size()) == metaInf)
+            if(file == "mimetype" || file.rfind(metaInf, 0) == 0)
                 continue;
             const auto directory = File::directory(file);
             if(directory.empty() || directory == "/" || directory == "./")
@@ -194,6 +198,9 @@ SiVaContainer::SiVaContainer(const string &path, bool useHashCode)
     else
         THROW("Unknown file");
 
+    if(cb && !cb->validateOnline())
+        THROW("Online validation disabled");
+
     array<XMLByte, 4800> buf{};
     string b64;
     is->clear();
@@ -220,6 +227,7 @@ SiVaContainer::SiVaContainer(const string &path, bool useHashCode)
     Connect::Result r = Connect(CONF(verifyServiceUri), "POST", 0, CONF(verifyServiceCerts)).exec({
         {"Content-Type", "application/json;charset=UTF-8"}
     }, (const unsigned char*)req.c_str(), req.size());
+    req.clear();
 
     if(!r.isOK() && !r.isStatusCode("400"))
         THROW("Failed to send request to SiVa");
@@ -287,7 +295,7 @@ SiVaContainer::SiVaContainer(const string &path, bool useHashCode)
         for(const json &error: signature.value<json>("errors", {}))
         {
             string message = error["content"];
-            if(message.find("Bad digest for DataFile") == 0 && useHashCode)
+            if(message.find("Bad digest for DataFile", 0) != string::npos && useHashCode)
                 THROW("%s", message.c_str());
             s->_exceptions.emplace_back(EXCEPTION_PARAMS("%s", message.c_str()));
         }
@@ -298,7 +306,7 @@ SiVaContainer::SiVaContainer(const string &path, bool useHashCode)
             if(message == "X509IssuerName has none or invalid namespace: null" ||
                 message == "X509SerialNumber has none or invalid namespace: null")
                 ex.setCode(Exception::IssuerNameSpaceWarning);
-            else if(message.find("Bad digest for DataFile") == 0)
+            else if(message.find("Bad digest for DataFile") != string::npos)
                 ex.setCode(Exception::DataFileNameSpaceWarning);
             else if(message == "Old and unsupported format: SK-XML version: 1.0")
                 continue;
@@ -344,15 +352,15 @@ vector<DataFile *> SiVaContainer::dataFiles() const
     return d->dataFiles;
 }
 
-unique_ptr<Container> SiVaContainer::openInternal(const string &path)
+unique_ptr<Container> SiVaContainer::openInternal(const string &path, ContainerOpenCB *cb)
 {
     try {
-        return unique_ptr<Container>(new SiVaContainer(path, true));
+        return unique_ptr<Container>(new SiVaContainer(path, cb, true));
     } catch(const Exception &e) {
-        if(e.msg().find("Bad digest for DataFile") == 0)
-            return unique_ptr<Container>(new SiVaContainer(path, false));
+        if(e.msg().find("Bad digest for DataFile") != string::npos)
+            return unique_ptr<Container>(new SiVaContainer(path, cb, false));
         if(e.msg() == "Unknown file")
-           return {};
+            return {};
         throw;
     }
 }
diff --git a/src/SiVaContainer.h b/src/SiVaContainer.h
index ce93edff7..9624771ff 100644
--- a/src/SiVaContainer.h
+++ b/src/SiVaContainer.h
@@ -99,13 +99,13 @@ class SiVaContainer final: public Container
     Signature* sign(Signer* signer) final;
 
     static std::unique_ptr<Container> createInternal(const std::string &path);
-    static std::unique_ptr<Container> openInternal(const std::string &path);
+    static std::unique_ptr<Container> openInternal(const std::string &path, ContainerOpenCB *cb);
 
 private:
-	SiVaContainer(const std::string &path, bool useHashCode);
+    SiVaContainer(const std::string &path, ContainerOpenCB *cb, bool useHashCode);
     DISABLE_COPY(SiVaContainer);
 
-	std::unique_ptr<std::istream> parseDDoc(bool useHashCode);
+    std::unique_ptr<std::istream> parseDDoc(bool useHashCode);
 
     class Private;
     std::unique_ptr<Private> d;
diff --git a/src/digidoc-tool.1.cmake b/src/digidoc-tool.1.cmake
index 79c2b5844..857a9e18d 100644
--- a/src/digidoc-tool.1.cmake
+++ b/src/digidoc-tool.1.cmake
@@ -27,6 +27,7 @@ Command open:
                              http://open-eid.github.io/SiVa/siva/appendix/validation_policy/
     --extractAll[=path]    - extracts documents without validating signatures (to path when provided)
     --validateOnExtract    - validates container before extracting files
+    --offline              - open container offline (eg. Don't send to SiVa)
 
 Command add:
   Example: digidoc-tool add --file=file1.txt container-file.asice
diff --git a/src/digidoc-tool.cpp b/src/digidoc-tool.cpp
index 70e496f49..dd67d56b4 100644
--- a/src/digidoc-tool.cpp
+++ b/src/digidoc-tool.cpp
@@ -326,6 +326,7 @@ static int printUsage(const char *executable)
     << "                               http://open-eid.github.io/SiVa/siva/appendix/validation_policy/" << endl
     << "      --extractAll[=path]    - extracts documents without validating signatures (to path when provided)" << endl
     << "      --validateOnExtract    - validates container before extracting files" << endl << endl
+    << "      --offline              - open container offline (eg. Don't send to SiVa)" << endl << endl
     << "  Command add:" << endl
     << "    Example: " << executable << " add --file=file1.txt container-file.asice" << endl
     << "    Available options:" << endl
@@ -539,6 +540,11 @@ static int open(int argc, char* argv[])
     fs::path extractPath;
     bool validateOnExtract = false;
     int returnCode = EXIT_SUCCESS;
+    struct OpenCB final: public ContainerOpenCB
+    {
+        bool online = true;
+        bool validateOnline() const final { return online; }
+    } cb;
 
     // Parse command line arguments.
     for(int i = 2; i < argc; i++)
@@ -566,6 +572,8 @@ static int open(int argc, char* argv[])
             validateOnExtract = true;
         else if(arg.find("--policy=") == 0)
             policy = arg.substr(9);
+        else if(arg.find("--offline") == 0)
+            cb.online = false;
         else
             path = arg;
     }
@@ -575,7 +583,7 @@ static int open(int argc, char* argv[])
 
     unique_ptr<Container> doc;
     try {
-        doc = Container::openPtr(path);
+        doc = Container::openPtr(path, &cb);
     } catch(const Exception &e) {
         cout << "Failed to parse container" << endl;
         cout << "  Exception:" << endl << e;