trigger NODATA error for invalid InRelease files

With the selfgrown splitting we got the problem of not recovering
from networks which just reply with invalid data like those sending
us login pages to authenticate with the network (e.g. hotels) back.

The good thing about the InRelease file is that we know that it must
be clearsigned (a Release file might or might not have a detached sig)
so if we get a file but are unable to split it something is seriously
wrong, so there is not much point in trying further.

The Acquire system already looks out for a NODATA error from gpgv,
so this adds a new error message sent to the acquire system in case
the splitting we do now ourselves failed including this magic word.

Closes: #712486

3 files changed, 93 insertions, 0 deletions

diff --git a/test/integration/framework b/test/integration/framework
index 3f11ac23b..3a02cfb76 100644
--- a/test/integration/framework
+++ b/test/integration/framework
@@ -118,6 +118,9 @@ gdb() {
 	echo "gdb: run »$*«"
 	APT_CONFIG=aptconfig.conf LD_LIBRARY_PATH=${BUILDDIRECTORY} $(which gdb) ${BUILDDIRECTORY}/$1
 }
+http() {
+	LD_LIBRARY_PATH=${BUILDDIRECTORY} ${BUILDDIRECTORY}/methods/http
+}
 
 exitwithstatus() {
         # error if we about to overflow, but ...
diff --git a/test/integration/test-ubuntu-bug-346386-apt-get-update-paywall b/test/integration/test-ubuntu-bug-346386-apt-get-update-paywall
new file mode 100755
index 000000000..1576c396c
--- /dev/null
+++ b/test/integration/test-ubuntu-bug-346386-apt-get-update-paywall
@@ -0,0 +1,64 @@
+#!/bin/sh
+set -e
+
+TESTDIR=$(readlink -f $(dirname $0))
+. $TESTDIR/framework
+
+setupenvironment
+configarchitecture 'native'
+
+insertpackage 'unstable' 'unrelated' 'all' '1.0' 'stable'
+insertsource 'unstable' 'unrelated' 'all' '1.0' 'stable'
+
+echo 'ni ni ni' > aptarchive/knights
+
+setupaptarchive
+changetowebserver -o 'aptwebserver::overwrite::.*::filename=/knights'
+
+msgtest 'Acquire test file from the webserver to check' 'overwrite'
+echo '601 Configuration
+Config-Item: Acquire::http::DependOnSTDIN=0
+
+600 Acquire URI
+URI: http://localhost:8080/holygrail
+Filename: knights-talking
+' | http >/dev/null 2>&1 && msgpass || msgfail
+testfileequal knights-talking 'ni ni ni'
+
+ensure_n_canary_strings_in_dir() {
+	local DIR="$1"
+	local CANARY_STRING="$2"
+	local EXPECTED_N="$3"
+
+	msgtest "Testing in $DIR for $EXPECTED_N canary" "$CANARY_STRING"
+	local N=$(grep "$CANARY_STRING" $DIR/* 2>/dev/null |wc -l )
+	test "$N" = "$EXPECTED_N" && msgpass || msgfail "Expected $EXPECTED_N canaries, got $N"
+}
+
+LISTS='rootdir/var/lib/apt/lists'
+rm -rf rootdir/var/lib/apt/lists
+msgtest 'Got expected NODATA failure in' 'apt-get update'
+aptget update -qq 2>&1 | grep -q 'E: GPG error.*NODATA' && msgpass || msgfail
+
+ensure_n_canary_strings_in_dir $LISTS 'ni ni ni' 0
+testequal 'partial' ls $LISTS
+
+# and again with pre-existing files with "valid data" which should remain
+for f in Release Release.gpg main_binary-amd64_Packages main_source_Sources; do
+    echo 'peng neee-wom' > $LISTS/localhost:8080_dists_stable_${f}
+done
+
+msgtest 'Got expected NODATA failure in' 'apt-get update'
+aptget update -qq 2>&1 | grep -q 'E: GPG error.*NODATA' && msgpass || msgfail
+
+ensure_n_canary_strings_in_dir $LISTS 'peng neee-wom' 4
+ensure_n_canary_strings_in_dir $LISTS 'ni ni ni' 0
+
+# and now with a pre-existing InRelease file
+echo 'peng neee-wom' > $LISTS/localhost:8080_dists_stable_InRelease
+rm -f $LISTS/localhost:8080_dists_stable_Release $LISTS/localhost:8080_dists_stable_Release.gpg
+msgtest 'excpected failure of' 'apt-get update'
+aptget update -qq 2>&1 | grep -q 'E: GPG error.*NODATA' && msgpass || msgfail
+
+ensure_n_canary_strings_in_dir $LISTS 'peng neee-wom' 3
+ensure_n_canary_strings_in_dir $LISTS 'ni ni ni' 0
diff --git a/test/interactive-helper/aptwebserver.cc b/test/interactive-helper/aptwebserver.cc
index de235fa05..05b875673 100644
--- a/test/interactive-helper/aptwebserver.cc
+++ b/test/interactive-helper/aptwebserver.cc
@@ -435,6 +435,32 @@ int main(int const argc, const char * argv[])
 	       }
 	    }
 
+	    ::Configuration::Item const *Overwrite = _config->Tree("aptwebserver::overwrite");
+	    if (Overwrite != NULL)
+	    {
+	       for (::Configuration::Item *I = Overwrite->Child; I != NULL; I = I->Next)
+	       {
+		  regex_t *pattern = new regex_t;
+		  int const res = regcomp(pattern, I->Tag.c_str(), REG_EXTENDED | REG_ICASE | REG_NOSUB);
+		  if (res != 0)
+		  {
+		     char error[300];
+		     regerror(res, pattern, error, sizeof(error));
+		     sendError(client, 500, *m, sendContent, error);
+		     continue;
+		  }
+		  if (regexec(pattern, filename.c_str(), 0, 0, 0) == 0)
+		  {
+		      filename = _config->Find("aptwebserver::overwrite::" + I->Tag + "::filename", filename);
+		      if (filename[0] == '/')
+			 filename.erase(0,1);
+		      regfree(pattern);
+		      break;
+		  }
+		  regfree(pattern);
+	       }
+	    }
+
 	    // deal with the request
 	    if (RealFileExists(filename) == true)
 	    {