use unusable-for-security hashes for integrity checks

We want to declare some hashes as not enough for security, so that a
user will need --allow-unauthenticated or similar to get data secured
only by those hashes, but we can still us these hashes for integrity
checks if we got them.

2 files changed, 7 insertions, 0 deletions

diff --git a/apt-pkg/acquire-worker.cc b/apt-pkg/acquire-worker.cc
index 176772dde..889768030 100644
--- a/apt-pkg/acquire-worker.cc
+++ b/apt-pkg/acquire-worker.cc
@@ -407,7 +407,13 @@ bool pkgAcquire::Worker::RunMessages()
 	       else if (Owner->HashesRequired() == true)
 		  consideredOkay = false;
 	       else
+	       {
 		  consideredOkay = true;
+		  // even if the hashes aren't usable to declare something secure
+		  // we can at least use them to declare it an integrity failure
+		  if (ExpectedHashes.empty() == false && ReceivedHashes != ExpectedHashes && _config->Find("Acquire::ForceHash").empty())
+		     consideredOkay = false;
+	       }
 
 	       if (consideredOkay == true)
 		  consideredOkay = Owner->VerifyDone(Message, Config);
diff --git a/apt-pkg/contrib/hashes.cc b/apt-pkg/contrib/hashes.cc
index 41a0037cd..5c0023dc7 100644
--- a/apt-pkg/contrib/hashes.cc
+++ b/apt-pkg/contrib/hashes.cc
@@ -136,6 +136,7 @@ APT_PURE bool HashString::usable() const				/*{{{*/
       (Type != "MD5Sum")
    );
 }
+									/*}}}*/
 std::string HashString::toStr() const					/*{{{*/
 {
    return Type + ":" + Hash;