support multiple fingerprints in signed-by

A keyring file can include multiple keys, so its only fair for
transitions and such to support multiple fingerprints as well.

apt-pkg/deb/debmetaindex.cc

@@ -627,19 +627,26 @@ bool debReleaseIndex::SetSignedBy(std::string const &pSignedBy)
    if (SignedBy.empty() == true && pSignedBy.empty() == false)
    {
       if (pSignedBy[0] == '/') // no check for existence as we could be chrooting later or such things
-	 ; // absolute path to a keyring file
+	 SignedBy = pSignedBy; // absolute path to a keyring file
       else
       {
 	 // we could go all fancy and allow short/long/string matches as gpgv/apt-key does,
 	 // but fingerprints are harder to fake than the others and this option is set once,
 	 // not interactively all the time so easy to type is not really a concern.
-	 std::string finger = pSignedBy;
-	 finger.erase(std::remove(finger.begin(), finger.end(), ' '), finger.end());
-	 std::transform(finger.begin(), finger.end(), finger.begin(), ::toupper);
-	 if (finger.length() != 40 || finger.find_first_not_of("0123456789ABCDEF") != std::string::npos)
-	    return _error->Error(_("Invalid value set for option %s regarding source %s %s (%s)"), "Signed-By", URI.c_str(), Dist.c_str(), "not a fingerprint");
+	 auto fingers = VectorizeString(pSignedBy, ',');
+	 std::transform(fingers.begin(), fingers.end(), fingers.begin(), [&](std::string finger) {
+	    std::transform(finger.begin(), finger.end(), finger.begin(), ::toupper);
+	    if (finger.length() != 40 || finger.find_first_not_of("0123456789ABCDEF") != std::string::npos)
+	    {
+	       _error->Error(_("Invalid value set for option %s regarding source %s %s (%s)"), "Signed-By", URI.c_str(), Dist.c_str(), "not a fingerprint");
+	       return std::string();
+	    }
+	    return finger;
+	 });
+	 std::stringstream os;
+	 std::copy(fingers.begin(), fingers.end(), std::ostream_iterator<std::string>(os, ","));
+	 SignedBy = os.str();
       }
-      SignedBy = pSignedBy;
    }
    else if (SignedBy != pSignedBy)
       return _error->Error(_("Conflicting values set for option %s regarding source %s %s"), "Signed-By", URI.c_str(), Dist.c_str());

doc/sources.list.5.xml

@@ -284,13 +284,13 @@ deb-src [ option1=value1 option2=value2 ] uri suite [component1] [component2] [.
 	  <listitem><para><option>Signed-By</option> (<option>signed-by</option>)
 		is either an absolute path to a keyring file (has to be
 		accessible and readable for the <literal>_apt</literal> user,
-		so ensure everyone has read-permissions on the file) or a
-		fingerprint of a key either in the
-		<filename>trusted.gpg</filename> keyring or in one of the
+		so ensure everyone has read-permissions on the file) or one or
+		more fingerprints of keys either in the
+		<filename>trusted.gpg</filename> keyring or in the
 		keyrings in the <filename>trusted.gpg.d/</filename> directory
 		(see <command>apt-key fingerprint</command>). If the option is
-		set, only the key(s) in this keyring or only the key with this
-		fingerprint is used for the &apt-secure; verification of this
+		set, only the key(s) in this keyring or only the keys with these
+		fingerprints are used for the &apt-secure; verification of this
 		repository. Otherwise all keys in the trusted keyrings are
 		considered valid signers for this repository.
 	  </para></listitem>

methods/gpgv.cc

@@ -249,25 +249,29 @@ string GPGVMethod::VerifyGetSigners(const char *file, const char *outfile,
    {
       if (Debug == true)
 	 std::clog << "GoodSigs needs to be limited to keyid " << key << std::endl;
-      std::vector<std::string>::iterator const foundItr = std::find(ValidSigners.begin(), ValidSigners.end(), key);
-      bool const found = (foundItr != ValidSigners.end());
-      std::copy(GoodSigners.begin(), GoodSigners.end(), std::back_insert_iterator<std::vector<std::string> >(NoPubKeySigners));
-      if (found)
+      bool foundGood = false;
+      for (auto const &k: VectorizeString(key, ','))
       {
+	 if (std::find(ValidSigners.begin(), ValidSigners.end(), k) == ValidSigners.end())
+	    continue;
 	 // we look for GOODSIG here as well as an expired sig is a valid sig as well (but not a good one)
-	 std::string const goodlongkeyid = "GOODSIG " + key.substr(24, 16);
-	 bool const foundGood = std::find(GoodSigners.begin(), GoodSigners.end(), goodlongkeyid) != GoodSigners.end();
+	 std::string const goodlongkeyid = "GOODSIG " + k.substr(24, 16);
+	 foundGood = std::find(GoodSigners.begin(), GoodSigners.end(), goodlongkeyid) != GoodSigners.end();
 	 if (Debug == true)
-	    std::clog << "Key " << key << " is valid sig, is " << goodlongkeyid << " also a good one? " << (foundGood ? "yes" : "no") << std::endl;
+	    std::clog << "Key " << k << " is valid sig, is " << goodlongkeyid << " also a good one? " << (foundGood ? "yes" : "no") << std::endl;
+	 if (foundGood == false)
+	    continue;
+	 std::copy(GoodSigners.begin(), GoodSigners.end(), std::back_insert_iterator<std::vector<std::string> >(NoPubKeySigners));
 	 GoodSigners.clear();
-	 if (foundGood)
-	 {
-	    GoodSigners.push_back(goodlongkeyid);
-	    NoPubKeySigners.erase(std::remove(NoPubKeySigners.begin(), NoPubKeySigners.end(), goodlongkeyid), NoPubKeySigners.end());
-	 }
+	 GoodSigners.push_back(goodlongkeyid);
+	 NoPubKeySigners.erase(std::remove(NoPubKeySigners.begin(), NoPubKeySigners.end(), goodlongkeyid), NoPubKeySigners.end());
+	 break;
       }
-      else
+      if (foundGood == false)
+      {
+	 std::copy(GoodSigners.begin(), GoodSigners.end(), std::back_insert_iterator<std::vector<std::string> >(NoPubKeySigners));
 	 GoodSigners.clear();
+      }
    }
 
    int status;

test/integration/test-releasefile-verification

@@ -33,6 +33,7 @@ prepare() {
 }
 
 installaptold() {
+	rm -rf rootdir/var/cache/apt/archives
 	testsuccessequal "Reading package lists...
 Building dependency tree...
 Suggested packages:
@@ -249,30 +250,57 @@ runtest() {
 	signreleasefiles 'Joe Sixpack'
 	find aptarchive/ -name "$DELETEFILE" -delete
 	updatewithwarnings '^W: .* NO_PUBKEY'
-
 	sed -i "s#^\(deb\(-src\)\?\) \[signed-by=$MARVIN\] #\1 #" rootdir/etc/apt/sources.list.d/*
+
 	local MARVIN="$(aptkey --keyring $MARVIN finger | grep 'Key fingerprint' | cut -d'=' -f 2 | tr -d ' ')"
+	msgmsg 'Cold archive signed by bad keyid' 'Joe Sixpack'
+	rm -rf rootdir/var/lib/apt/lists
+	signreleasefiles 'Joe Sixpack'
+	find aptarchive/ -name "$DELETEFILE" -delete
+	sed -i "s#^\(deb\(-src\)\?\) #\1 [signed-by=$MARVIN] #" rootdir/etc/apt/sources.list.d/*
+	updatewithwarnings '^W: .* be verified because the public key is not available: .*'
 
 	msgmsg 'Cold archive signed by good keyid' 'Marvin Paranoid'
-	prepare "${PKGFILE}"
 	rm -rf rootdir/var/lib/apt/lists
 	signreleasefiles 'Marvin Paranoid'
 	find aptarchive/ -name "$DELETEFILE" -delete
-	sed -i "s#^\(deb\(-src\)\?\) #\1 [signed-by=$MARVIN] #" rootdir/etc/apt/sources.list.d/*
 	cp keys/marvinparanoid.pub rootdir/etc/apt/trusted.gpg.d/marvinparanoid.gpg
 	successfulaptgetupdate
 	testsuccessequal "$(cat "${PKGFILE}")
 " aptcache show apt
 	installaptold
-	rm -f rootdir/etc/apt/trusted.gpg.d/marvinparanoid.gpg
 
-	msgmsg 'Cold archive signed by bad keyid' 'Joe Sixpack'
+	msgmsg 'Cold archive signed by good keyid' 'Marvin Paranoid,Joe Sixpack'
+	rm -rf rootdir/var/lib/apt/lists
+	signreleasefiles 'Marvin Paranoid,Joe Sixpack'
+	find aptarchive/ -name "$DELETEFILE" -delete
+	successfulaptgetupdate 'NoPubKey: GOODSIG'
+	testsuccessequal "$(cat "${PKGFILE}")
+" aptcache show apt
+	installaptold
+
+	local SIXPACK="$(aptkey --keyring keys/joesixpack.pub finger | grep 'Key fingerprint' | cut -d'=' -f 2 | tr -d ' ')"
+	msgmsg 'Cold archive signed by good keyids' 'Joe Sixpack'
 	rm -rf rootdir/var/lib/apt/lists
 	signreleasefiles 'Joe Sixpack'
 	find aptarchive/ -name "$DELETEFILE" -delete
-	updatewithwarnings '^W: .* be verified because the public key is not available: .*'
+	sed -i "s#^\(deb\(-src\)\?\) \[signed-by=$MARVIN\] #\1 [signed-by=${SIXPACK},${MARVIN}] #" rootdir/etc/apt/sources.list.d/*
+	successfulaptgetupdate
+	testsuccessequal "$(cat "${PKGFILE}")
+" aptcache show apt
+	installaptold
+
+	local SIXPACK="$(aptkey --keyring keys/joesixpack.pub finger | grep 'Key fingerprint' | cut -d'=' -f 2 | tr -d ' ')"
+	msgmsg 'Cold archive signed by good keyids' 'Joe Sixpack'
+	rm -rf rootdir/var/lib/apt/lists
+	sed -i "s#^\(deb\(-src\)\?\) \[signed-by=${SIXPACK},${MARVIN}\] #\1 [signed-by=${MARVIN},${SIXPACK}] #" rootdir/etc/apt/sources.list.d/*
+	successfulaptgetupdate
+	testsuccessequal "$(cat "${PKGFILE}")
+" aptcache show apt
+	installaptold
+	rm -f rootdir/etc/apt/trusted.gpg.d/marvinparanoid.gpg
+	sed -i "s#^\(deb\(-src\)\?\) \[signed-by=${MARVIN},${SIXPACK}\] #\1 #" rootdir/etc/apt/sources.list.d/*
 
-	sed -i "s#^\(deb\(-src\)\?\) \[signed-by=$MARVIN\] #\1 #" rootdir/etc/apt/sources.list.d/*
 }
 
 runtest2() {