warn if clearsigned file has ignored content parts

Clearsigned files like InRelease, .dsc, .changes and co can potentially
include unsigned or additional messages blocks ignored by gpg in
verification, but a potential source of trouble in our own parsing
attempts – and an unneeded risk as the usecases for the clearsigned
files we deal with do not reasonably include unsigned parts (like emails
or some such).

This commit changes the silent ignoring to warnings for now to get an
impression on how widespread unintended unsigned parts are, but
eventually we want to turn these into hard errors.

5 files changed, 377 insertions, 4 deletions

diff --git a/apt-pkg/contrib/gpgv.cc b/apt-pkg/contrib/gpgv.cc
index b6c4b6e08..0878a7ffb 100644
--- a/apt-pkg/contrib/gpgv.cc
+++ b/apt-pkg/contrib/gpgv.cc
@@ -145,7 +145,6 @@ void ExecGPGV(std::string const &File, std::string const &FileGPG,
    }
 
    enum  { DETACHED, CLEARSIGNED } releaseSignature = (FileGPG != File) ? DETACHED : CLEARSIGNED;
-   std::vector<std::string> dataHeader;
    char * sig = NULL;
    char * data = NULL;
    char * conf = nullptr;
@@ -204,7 +203,7 @@ void ExecGPGV(std::string const &File, std::string const &FileGPG,
       message.OpenDescriptor(dataFd, FileFd::WriteOnly, true);
 
       if (signature.Failed() == true || message.Failed() == true ||
-	    SplitClearSignedFile(File, &message, &dataHeader, &signature) == false)
+	    SplitClearSignedFile(File, &message, nullptr, &signature) == false)
       {
 	 apt_error(std::cerr, statusfd, fd, "Splitting up %s into data and signature failed", File.c_str());
 	 local_exit(112);
@@ -313,6 +312,8 @@ bool SplitClearSignedFile(std::string const &InFile, FileFd * const ContentFile,
    bool skip_until_empty_line = false;
    bool found_signature = false;
    bool first_line = true;
+   bool signed_message_not_on_first_line = false;
+   bool found_garbage = false;
 
    char *buf = NULL;
    size_t buf_size = 0;
@@ -327,6 +328,8 @@ bool SplitClearSignedFile(std::string const &InFile, FileFd * const ContentFile,
 	    found_message_start = true;
 	    skip_until_empty_line = true;
 	 }
+	 else
+	    signed_message_not_on_first_line = found_garbage = true;
       }
       else if (skip_until_empty_line == true)
       {
@@ -364,6 +367,8 @@ bool SplitClearSignedFile(std::string const &InFile, FileFd * const ContentFile,
 	    if (ContentFile != NULL)
 	       ContentFile->Write(dashfree, strlen(dashfree));
 	 }
+	 else
+	    found_garbage = true;
       }
       else if (found_signature == true)
       {
@@ -376,6 +381,8 @@ bool SplitClearSignedFile(std::string const &InFile, FileFd * const ContentFile,
 	    found_signature = false; // look for other signatures
       }
       // all the rest is whitespace, unsigned garbage or additional message blocks we ignore
+      else
+	 found_garbage = true;
    }
    fclose(in);
    if (buf != NULL)
@@ -387,6 +394,14 @@ bool SplitClearSignedFile(std::string const &InFile, FileFd * const ContentFile,
    if (ContentFile != nullptr)
       ContentFile->Flush();
 
+   if (found_message_start)
+   {
+      if (signed_message_not_on_first_line)
+	 _error->Warning("Clearsigned file '%s' does not start with a signed message block.", InFile.c_str());
+      else if (found_garbage)
+	 _error->Warning("Clearsigned file '%s' contains unsigned lines.", InFile.c_str());
+   }
+
    // An error occured during reading - propagate it up
    bool const hasErrored = _error->PendingError();
    _error->MergeWithStack();
diff --git a/test/integration/test-cve-2013-1051-InRelease-parsing b/test/integration/test-cve-2013-1051-InRelease-parsing
index 3cc012e35..6238057c3 100755
--- a/test/integration/test-cve-2013-1051-InRelease-parsing
+++ b/test/integration/test-cve-2013-1051-InRelease-parsing
@@ -45,8 +45,10 @@ touch -d '+1hour' aptarchive/dists/stable/InRelease
 # part of the InRelease
 listcurrentlistsdirectory | sed '/_InRelease/ d' > listsdir.lst
 msgtest 'apt-get update should ignore unsigned data in the' 'InRelease'
-testsuccessequal "Get:1 http://localhost:${APTHTTPPORT} stable InRelease [$(stat -c%s aptarchive/dists/stable/InRelease) B]
-Reading package lists..." --nomsg aptget update
+testwarningequal "Get:1 http://localhost:${APTHTTPPORT} stable InRelease [$(stat -c%s aptarchive/dists/stable/InRelease) B]
+Reading package lists...
+W: Clearsigned file '${TMPWORKINGDIRECTORY}/rootdir/var/lib/apt/lists/partial/localhost:${APTHTTPPORT}_dists_stable_InRelease' contains unsigned lines.
+W: Clearsigned file '${TMPWORKINGDIRECTORY}/rootdir/var/lib/apt/lists/localhost:${APTHTTPPORT}_dists_stable_InRelease' contains unsigned lines." --nomsg aptget update
 testfileequal './listsdir.lst' "$(listcurrentlistsdirectory | sed '/_InRelease/ d')"
 
 # ensure there is no package
diff --git a/test/libapt/getlanguages_test.cc b/test/libapt/getlanguages_test.cc
index c50ff6ff8..29ff0c9ae 100644
--- a/test/libapt/getlanguages_test.cc
+++ b/test/libapt/getlanguages_test.cc
@@ -2,6 +2,7 @@
 
 #include <apt-pkg/aptconfiguration.h>
 #include <apt-pkg/configuration.h>
+#include <apt-pkg/error.h>
 #include <apt-pkg/fileutl.h>
 
 #include <algorithm>
@@ -214,6 +215,7 @@ TEST(LanguagesTest,TranslationFiles)
    EXPECT_EQ(1, vec.size());
    EXPECT_EQ("none", vec[0]);
 
+   _error->PushToStack();
    _config->Set("Acquire::Languages", "");
    //FIXME: Remove support for this deprecated setting
    _config->Set("APT::Acquire::Translation", "ast_DE");
@@ -228,6 +230,11 @@ TEST(LanguagesTest,TranslationFiles)
    EXPECT_EQ(1, vec.size());
    EXPECT_EQ("en", vec[0]);
 
+   // discard the deprecation warning for APT::Acquire::Translation
+   if (_error->PendingError())
+      _error->MergeWithStack();
+   else
+      _error->RevertToStack();
 
    EXPECT_EQ(0, system(std::string("rm -rf ").append(tempdir).c_str()));
    _config->Clear();
diff --git a/test/libapt/getlistoffilesindir_test.cc b/test/libapt/getlistoffilesindir_test.cc
index 2369c911a..8c5e56b1d 100644
--- a/test/libapt/getlistoffilesindir_test.cc
+++ b/test/libapt/getlistoffilesindir_test.cc
@@ -1,6 +1,7 @@
 #include <config.h>
 
 #include <apt-pkg/fileutl.h>
+#include <apt-pkg/error.h>
 
 #include <string>
 #include <vector>
@@ -49,6 +50,7 @@ TEST(FileUtlTest,GetListOfFilesInDir)
    createLink(tempdir, "non-existing-file", "brokenlink.list");
 
    // Files with no extension
+   _error->PushToStack();
    std::vector<std::string> files = GetListOfFilesInDir(tempdir, "", true);
    ASSERT_EQ(2, files.size());
    EXPECT_EQ(P("01yet-anothernormalfile"), files[0]);
@@ -103,5 +105,10 @@ TEST(FileUtlTest,GetListOfFilesInDir)
    EXPECT_EQ(P("disabledfile.disabled"), files[3]);
    EXPECT_EQ(P("disabledfile.list.disabled"), files[4]);
 
+   // discard the unknown file extension messages
+   if (_error->PendingError())
+      _error->MergeWithStack();
+   else
+      _error->RevertToStack();
    removeDirectory(tempdir);
 }
diff --git a/test/libapt/openmaybeclearsignedfile_test.cc b/test/libapt/openmaybeclearsignedfile_test.cc
new file mode 100644
index 000000000..40735812d
--- /dev/null
+++ b/test/libapt/openmaybeclearsignedfile_test.cc
@@ -0,0 +1,342 @@
+#include <config.h>
+
+#include <apt-pkg/error.h>
+#include <apt-pkg/fileutl.h>
+#include <apt-pkg/gpgv.h>
+
+#include <string>
+
+#include <gtest/gtest.h>
+
+#include "file-helpers.h"
+
+/* The test files are created with the 'Joe Sixpack' and 'Marvin Paranoid'
+   test key included in the integration testing framework */
+
+TEST(OpenMaybeClearSignedFileTest,SimpleSignedFile)
+{
+   std::string tempfile;
+   FileFd fd;
+   // Using c++11 raw-strings would be nifty, but travis doesn't support it…
+   createTemporaryFile("simplesignedfile", fd, &tempfile, "-----BEGIN PGP SIGNED MESSAGE-----\n"
+"Hash: SHA512\n"
+"\n"
+"Test\n"
+"-----BEGIN PGP SIGNATURE-----\n"
+"\n"
+"iQFEBAEBCgAuFiEENKjp0Y2zIPNn6OqgWpDRQdusja4FAlhT7+kQHGpvZUBleGFt\n"
+"cGxlLm9yZwAKCRBakNFB26yNrjvEB/9/e3jA1l0fvPafx9LEXcH8CLpUFQK7ra9l\n"
+"3M4YAH4JKQlTG1be7ixruBRlCTh3YiSs66fKMeJeUYoxA2HPhvbGFEjQFAxunEYg\n"
+"X/LBKv1mQWa+Q34P5GBjK8kQdLCN+yJAiUErmWNQG3GPninrxsC9tY5jcWvHeP1k\n"
+"V7N3MLnNqzXaCJM24mnKidC5IDadUdQ8qC8c3rjUexQ8vBz0eucH56jbqV5oOcvx\n"
+"pjlW965dCPIf3OI8q6J7bIOjyY+u/PTcVlqPq3TUz/ti6RkVbKpLH0D4ll3lUTns\n"
+"JQt/+gJCPxHUJphy8sccBKhW29CLELJIIafvU30E1nWn9szh2Xjq\n"
+"=TB1F\n"
+"-----END PGP SIGNATURE-----\n");
+
+   EXPECT_TRUE(OpenMaybeClearSignedFile(tempfile, fd));
+   if (tempfile.empty() == false)
+      unlink(tempfile.c_str());
+   EXPECT_TRUE(fd.IsOpen());
+   char buffer[100];
+   EXPECT_TRUE(fd.ReadLine(buffer, sizeof(buffer)));
+   EXPECT_STREQ(buffer, "Test");
+   EXPECT_TRUE(fd.Eof());
+}
+
+TEST(OpenMaybeClearSignedFileTest,WhitespaceSignedFile)
+{
+   std::string tempfile;
+   FileFd fd;
+   // no raw-string here to protect the whitespace from cleanup
+   createTemporaryFile("simplesignedfile", fd, &tempfile, "-----BEGIN PGP SIGNED MESSAGE----- \t    \n"
+"Hash:    SHA512     \n"
+"	   \n"
+"Test	\n"
+"-----BEGIN PGP SIGNATURE----- \n"
+"   \n"
+"iQFEBAEBCgAuFiEENKjp0Y2zIPNn6OqgWpDRQdusja4FAlhT7+kQHGpvZUBleGFt \n"
+"cGxlLm9yZwAKCRBakNFB26yNrjvEB/9/e3jA1l0fvPafx9LEXcH8CLpUFQK7ra9l	\n"
+"3M4YAH4JKQlTG1be7ixruBRlCTh3YiSs66fKMeJeUYoxA2HPhvbGFEjQFAxunEYg \n"
+"X/LBKv1mQWa+Q34P5GBjK8kQdLCN+yJAiUErmWNQG3GPninrxsC9tY5jcWvHeP1k \n"
+"V7N3MLnNqzXaCJM24mnKidC5IDadUdQ8qC8c3rjUexQ8vBz0eucH56jbqV5oOcvx \n"
+"pjlW965dCPIf3OI8q6J7bIOjyY+u/PTcVlqPq3TUz/ti6RkVbKpLH0D4ll3lUTns	\n"
+"JQt/+gJCPxHUJphy8sccBKhW29CLELJIIafvU30E1nWn9szh2Xjq			\n"
+"=TB1F	\n"
+"-----END PGP SIGNATURE-----");
+
+   EXPECT_TRUE(OpenMaybeClearSignedFile(tempfile, fd));
+   if (tempfile.empty() == false)
+      unlink(tempfile.c_str());
+   EXPECT_TRUE(fd.IsOpen());
+   char buffer[100];
+   EXPECT_TRUE(fd.ReadLine(buffer, sizeof(buffer)));
+   EXPECT_STREQ(buffer, "Test");
+   EXPECT_TRUE(fd.Eof());
+}
+
+TEST(OpenMaybeClearSignedFileTest,SignedFileWithContentHeaders)
+{
+   std::string tempfile;
+   FileFd fd;
+   createTemporaryFile("headerssignedfile", fd, &tempfile, "-----BEGIN PGP SIGNED MESSAGE-----\n"
+"Version: 0.8.15~exp1\n"
+"Hash: SHA512\n"
+"Comment: I love you!\n"
+"X-Expires: never\n"
+"Multilines: no\n"
+" yes\n"
+" maybe\n"
+"\n"
+"Test\n"
+"-----BEGIN PGP SIGNATURE-----\n"
+"\n"
+"iQFEBAEBCgAuFiEENKjp0Y2zIPNn6OqgWpDRQdusja4FAlhT7+kQHGpvZUBleGFt\n"
+"cGxlLm9yZwAKCRBakNFB26yNrjvEB/9/e3jA1l0fvPafx9LEXcH8CLpUFQK7ra9l\n"
+"3M4YAH4JKQlTG1be7ixruBRlCTh3YiSs66fKMeJeUYoxA2HPhvbGFEjQFAxunEYg\n"
+"X/LBKv1mQWa+Q34P5GBjK8kQdLCN+yJAiUErmWNQG3GPninrxsC9tY5jcWvHeP1k\n"
+"V7N3MLnNqzXaCJM24mnKidC5IDadUdQ8qC8c3rjUexQ8vBz0eucH56jbqV5oOcvx\n"
+"pjlW965dCPIf3OI8q6J7bIOjyY+u/PTcVlqPq3TUz/ti6RkVbKpLH0D4ll3lUTns\n"
+"JQt/+gJCPxHUJphy8sccBKhW29CLELJIIafvU30E1nWn9szh2Xjq\n"
+"=TB1F\n"
+"-----END PGP SIGNATURE-----\n");
+
+   EXPECT_TRUE(OpenMaybeClearSignedFile(tempfile, fd));
+   if (tempfile.empty() == false)
+      unlink(tempfile.c_str());
+   EXPECT_TRUE(fd.IsOpen());
+   char buffer[100];
+   EXPECT_TRUE(fd.ReadLine(buffer, sizeof(buffer)));
+   EXPECT_STREQ(buffer, "Test");
+   EXPECT_TRUE(fd.Eof());
+}
+
+// That isn't how multiple signatures are done
+TEST(OpenMaybeClearSignedFileTest,SignedFileWithTwoSignatures)
+{
+   std::string tempfile;
+   FileFd fd;
+   createTemporaryFile("doublesignedfile", fd, &tempfile, "-----BEGIN PGP SIGNED MESSAGE-----\n"
+"Hash: SHA512\n"
+"\n"
+"Test\n"
+"-----BEGIN PGP SIGNATURE-----\n"
+"\n"
+"iQFEBAEBCgAuFiEENKjp0Y2zIPNn6OqgWpDRQdusja4FAlhT7+kQHGpvZUBleGFt\n"
+"cGxlLm9yZwAKCRBakNFB26yNrjvEB/9/e3jA1l0fvPafx9LEXcH8CLpUFQK7ra9l\n"
+"3M4YAH4JKQlTG1be7ixruBRlCTh3YiSs66fKMeJeUYoxA2HPhvbGFEjQFAxunEYg\n"
+"X/LBKv1mQWa+Q34P5GBjK8kQdLCN+yJAiUErmWNQG3GPninrxsC9tY5jcWvHeP1k\n"
+"V7N3MLnNqzXaCJM24mnKidC5IDadUdQ8qC8c3rjUexQ8vBz0eucH56jbqV5oOcvx\n"
+"pjlW965dCPIf3OI8q6J7bIOjyY+u/PTcVlqPq3TUz/ti6RkVbKpLH0D4ll3lUTns\n"
+"JQt/+gJCPxHUJphy8sccBKhW29CLELJIIafvU30E1nWn9szh2Xjq\n"
+"=TB1F\n"
+"-----END PGP SIGNATURE-----\n"
+"-----BEGIN PGP SIGNATURE-----\n"
+"\n"
+"iQFHBAEBCgAxFiEE3mauypFRr6GHfsMd6FJdR1KBROIFAlhT/yYTHG1hcnZpbkBl\n"
+"eGFtcGxlLm9yZwAKCRDoUl1HUoFE4qq3B/459MSk3xCW30wc5+ul5ZxTSg6eLYPJ\n"
+"tfVNYi90/ZxRrYQAN+EWozEIZcxoMYp8Ans3++irkjPbHs4NsesmFKt2W5meFl4V\n"
+"oUzYrOh5y5GlDeF7ok5g9atQe8BojjBics+g1IBYcnaMU+ywONmlixa03IPGfxV5\n"
+"oTx02Xvlns20i6HRc0WFtft5q1hXo4EIlVc9O0u902SVEEkeuHF3+bCcXrNLPBJA\n"
+"+8dxmH5+i89f/kVqURrdHdEuA1tsTNyb2C+lvRONh21H8QRRTU/iUQSzV6vZvof5\n"
+"ASc9hsAZRG0xHuRU0F94V/XrkWw8QYAobJ/yxvs4L0EuA4optbSqawDB\n"
+"=CP8j\n"
+"-----END PGP SIGNATURE-----\n");
+
+   EXPECT_TRUE(OpenMaybeClearSignedFile(tempfile, fd));
+   if (tempfile.empty() == false)
+      unlink(tempfile.c_str());
+   EXPECT_TRUE(fd.IsOpen());
+   char buffer[100];
+   EXPECT_TRUE(fd.ReadLine(buffer, sizeof(buffer)));
+   EXPECT_STREQ(buffer, "Test");
+   EXPECT_TRUE(fd.Eof());
+}
+
+TEST(OpenMaybeClearSignedFileTest,TwoSimpleSignedFile)
+{
+   std::string tempfile;
+   FileFd fd;
+   // read only the first message
+   createTemporaryFile("twosimplesignedfile", fd, &tempfile, "-----BEGIN PGP SIGNED MESSAGE-----\n"
+"Hash: SHA512\n"
+"\n"
+"Test\n"
+"-----BEGIN PGP SIGNATURE-----\n"
+"\n"
+"iQFEBAEBCgAuFiEENKjp0Y2zIPNn6OqgWpDRQdusja4FAlhT7+kQHGpvZUBleGFt\n"
+"cGxlLm9yZwAKCRBakNFB26yNrjvEB/9/e3jA1l0fvPafx9LEXcH8CLpUFQK7ra9l\n"
+"3M4YAH4JKQlTG1be7ixruBRlCTh3YiSs66fKMeJeUYoxA2HPhvbGFEjQFAxunEYg\n"
+"X/LBKv1mQWa+Q34P5GBjK8kQdLCN+yJAiUErmWNQG3GPninrxsC9tY5jcWvHeP1k\n"
+"V7N3MLnNqzXaCJM24mnKidC5IDadUdQ8qC8c3rjUexQ8vBz0eucH56jbqV5oOcvx\n"
+"pjlW965dCPIf3OI8q6J7bIOjyY+u/PTcVlqPq3TUz/ti6RkVbKpLH0D4ll3lUTns\n"
+"JQt/+gJCPxHUJphy8sccBKhW29CLELJIIafvU30E1nWn9szh2Xjq\n"
+"=TB1F\n"
+"-----END PGP SIGNATURE-----\n"
+"-----BEGIN PGP SIGNED MESSAGE-----\n"
+"Hash: SHA512\n"
+"\n"
+"Test\n"
+"-----BEGIN PGP SIGNATURE-----\n"
+"\n"
+"iQFEBAEBCgAuFiEENKjp0Y2zIPNn6OqgWpDRQdusja4FAlhT7+kQHGpvZUBleGFt\n"
+"cGxlLm9yZwAKCRBakNFB26yNrjvEB/9/e3jA1l0fvPafx9LEXcH8CLpUFQK7ra9l\n"
+"3M4YAH4JKQlTG1be7ixruBRlCTh3YiSs66fKMeJeUYoxA2HPhvbGFEjQFAxunEYg\n"
+"X/LBKv1mQWa+Q34P5GBjK8kQdLCN+yJAiUErmWNQG3GPninrxsC9tY5jcWvHeP1k\n"
+"V7N3MLnNqzXaCJM24mnKidC5IDadUdQ8qC8c3rjUexQ8vBz0eucH56jbqV5oOcvx\n"
+"pjlW965dCPIf3OI8q6J7bIOjyY+u/PTcVlqPq3TUz/ti6RkVbKpLH0D4ll3lUTns\n"
+"JQt/+gJCPxHUJphy8sccBKhW29CLELJIIafvU30E1nWn9szh2Xjq\n"
+"=TB1F\n"
+"-----END PGP SIGNATURE-----");
+
+   EXPECT_TRUE(_error->empty());
+   EXPECT_TRUE(OpenMaybeClearSignedFile(tempfile, fd));
+   if (tempfile.empty() == false)
+      unlink(tempfile.c_str());
+   EXPECT_FALSE(_error->empty());
+   EXPECT_TRUE(fd.IsOpen());
+   char buffer[100];
+   EXPECT_TRUE(fd.ReadLine(buffer, sizeof(buffer)));
+   EXPECT_STREQ(buffer, "Test");
+   EXPECT_TRUE(fd.Eof());
+   ASSERT_FALSE(_error->empty());
+
+   std::string msg;
+   _error->PopMessage(msg);
+   EXPECT_EQ("Clearsigned file '" + tempfile + "' contains unsigned lines.", msg);
+}
+
+TEST(OpenMaybeClearSignedFileTest,UnsignedFile)
+{
+   std::string tempfile;
+   FileFd fd;
+   createTemporaryFile("unsignedfile", fd, &tempfile, "Test");
+
+   EXPECT_TRUE(OpenMaybeClearSignedFile(tempfile, fd));
+   if (tempfile.empty() == false)
+      unlink(tempfile.c_str());
+   EXPECT_TRUE(fd.IsOpen());
+   char buffer[100];
+   EXPECT_TRUE(fd.ReadLine(buffer, sizeof(buffer)));
+   EXPECT_STREQ(buffer, "Test");
+   EXPECT_TRUE(fd.Eof());
+}
+
+TEST(OpenMaybeClearSignedFileTest,GarbageTop)
+{
+   std::string tempfile;
+   FileFd fd;
+   createTemporaryFile("garbagetop", fd, &tempfile, "Garbage\n"
+"-----BEGIN PGP SIGNED MESSAGE-----\n"
+"Hash: SHA512\n"
+"\n"
+"Test\n"
+"-----BEGIN PGP SIGNATURE-----\n"
+"\n"
+"iQFEBAEBCgAuFiEENKjp0Y2zIPNn6OqgWpDRQdusja4FAlhT7+kQHGpvZUBleGFt\n"
+"cGxlLm9yZwAKCRBakNFB26yNrjvEB/9/e3jA1l0fvPafx9LEXcH8CLpUFQK7ra9l\n"
+"3M4YAH4JKQlTG1be7ixruBRlCTh3YiSs66fKMeJeUYoxA2HPhvbGFEjQFAxunEYg\n"
+"X/LBKv1mQWa+Q34P5GBjK8kQdLCN+yJAiUErmWNQG3GPninrxsC9tY5jcWvHeP1k\n"
+"V7N3MLnNqzXaCJM24mnKidC5IDadUdQ8qC8c3rjUexQ8vBz0eucH56jbqV5oOcvx\n"
+"pjlW965dCPIf3OI8q6J7bIOjyY+u/PTcVlqPq3TUz/ti6RkVbKpLH0D4ll3lUTns\n"
+"JQt/+gJCPxHUJphy8sccBKhW29CLELJIIafvU30E1nWn9szh2Xjq\n"
+"=TB1F\n"
+"-----END PGP SIGNATURE-----\n");
+
+   EXPECT_TRUE(_error->empty());
+   EXPECT_TRUE(OpenMaybeClearSignedFile(tempfile, fd));
+   if (tempfile.empty() == false)
+      unlink(tempfile.c_str());
+   EXPECT_TRUE(fd.IsOpen());
+   char buffer[100];
+   EXPECT_TRUE(fd.ReadLine(buffer, sizeof(buffer)));
+   EXPECT_STREQ(buffer, "Test");
+   EXPECT_TRUE(fd.Eof());
+   ASSERT_FALSE(_error->empty());
+   ASSERT_FALSE(_error->PendingError());
+
+   std::string msg;
+   _error->PopMessage(msg);
+   EXPECT_EQ("Clearsigned file '" + tempfile + "' does not start with a signed message block.", msg);
+}
+
+TEST(OpenMaybeClearSignedFileTest,GarbageBottom)
+{
+   std::string tempfile;
+   FileFd fd;
+   createTemporaryFile("garbagebottom", fd, &tempfile, "-----BEGIN PGP SIGNED MESSAGE-----\n"
+"Hash: SHA512\n"
+"\n"
+"Test\n"
+"-----BEGIN PGP SIGNATURE-----\n"
+"\n"
+"iQFEBAEBCgAuFiEENKjp0Y2zIPNn6OqgWpDRQdusja4FAlhT7+kQHGpvZUBleGFt\n"
+"cGxlLm9yZwAKCRBakNFB26yNrjvEB/9/e3jA1l0fvPafx9LEXcH8CLpUFQK7ra9l\n"
+"3M4YAH4JKQlTG1be7ixruBRlCTh3YiSs66fKMeJeUYoxA2HPhvbGFEjQFAxunEYg\n"
+"X/LBKv1mQWa+Q34P5GBjK8kQdLCN+yJAiUErmWNQG3GPninrxsC9tY5jcWvHeP1k\n"
+"V7N3MLnNqzXaCJM24mnKidC5IDadUdQ8qC8c3rjUexQ8vBz0eucH56jbqV5oOcvx\n"
+"pjlW965dCPIf3OI8q6J7bIOjyY+u/PTcVlqPq3TUz/ti6RkVbKpLH0D4ll3lUTns\n"
+"JQt/+gJCPxHUJphy8sccBKhW29CLELJIIafvU30E1nWn9szh2Xjq\n"
+"=TB1F\n"
+"-----END PGP SIGNATURE-----\n"
+"Garbage");
+
+   EXPECT_TRUE(_error->empty());
+   EXPECT_TRUE(OpenMaybeClearSignedFile(tempfile, fd));
+   if (tempfile.empty() == false)
+      unlink(tempfile.c_str());
+   EXPECT_TRUE(fd.IsOpen());
+   char buffer[100];
+   EXPECT_TRUE(fd.ReadLine(buffer, sizeof(buffer)));
+   EXPECT_STREQ(buffer, "Test");
+   EXPECT_TRUE(fd.Eof());
+   ASSERT_FALSE(_error->empty());
+   ASSERT_FALSE(_error->PendingError());
+
+   std::string msg;
+   _error->PopMessage(msg);
+   EXPECT_EQ("Clearsigned file '" + tempfile + "' contains unsigned lines.", msg);
+}
+
+TEST(OpenMaybeClearSignedFileTest,BogusNoSig)
+{
+   std::string tempfile;
+   FileFd fd;
+   createTemporaryFile("bogusnosig", fd, &tempfile, "-----BEGIN PGP SIGNED MESSAGE-----\n"
+"Hash: SHA512\n"
+"\n"
+"Test");
+
+   EXPECT_TRUE(_error->empty());
+   EXPECT_FALSE(OpenMaybeClearSignedFile(tempfile, fd));
+   if (tempfile.empty() == false)
+      unlink(tempfile.c_str());
+   EXPECT_FALSE(_error->empty());
+   EXPECT_FALSE(fd.IsOpen());
+
+   std::string msg;
+   _error->PopMessage(msg);
+   EXPECT_EQ("Splitting of file " + tempfile + " failed as it doesn't contain all expected parts 0 1 0", msg);
+}
+
+TEST(OpenMaybeClearSignedFileTest,BogusSigStart)
+{
+   std::string tempfile;
+   FileFd fd;
+   createTemporaryFile("bogusnosig", fd, &tempfile, "-----BEGIN PGP SIGNED MESSAGE-----\n"
+"Hash: SHA512\n"
+"\n"
+"Test\n"
+"-----BEGIN PGP SIGNATURE-----");
+
+   EXPECT_TRUE(_error->empty());
+   EXPECT_FALSE(OpenMaybeClearSignedFile(tempfile, fd));
+   if (tempfile.empty() == false)
+      unlink(tempfile.c_str());
+   EXPECT_FALSE(_error->empty());
+   EXPECT_FALSE(fd.IsOpen());
+
+   std::string msg;
+   _error->PopMessage(msg);
+   EXPECT_EQ("Signature in file " + tempfile + " wasn't closed", msg);
+}