apl-cornell / chiselflow Goto Github PK

Add a sub project which can be used to supply some demonstrations.
Also add a README.md for running these and explaining how IFC is enforced.

Currently you have to label the outer "Flipped" itself rather than its contents (which may be an Input), it would be nicer for Flipped objects to pick up a label from the innermost non-flipped object by default.

Currently the Chisel test suite does not pass at all for mismatched syntax and other reasons. Only code with appropriate labels actually passes the chisel compilation phase.

We need to update the test suite and add unit tests for examples that actually use the IFC label features extensively.

Issue description:
We use Decoupled object to create handshake interface. For example, val test = Decoupled(UInt(128.W)) produces a 128-bit output with valid/ready interface. In secure chisel extension, the API is apply(gen: T, rdyl: Label = UnknownLabel, vall: Label = UnknownLabel) to specify labels. In the API, only ready and valid signals are explicitly labeled, and the bits should be implicitly labeled with data type gen. But the compiler does not work as expected, the bits is not labeled in the generated firrtl.

Example code:

class Test extends Module { 
   val io = IO(new Bundle {
       val msg_o = Decoupled(UInt(128.W, bot), bot, bot)
   })
}

Error message: [declaration io, with bad field bits in internal record msg_o : {ready : {L, H}, valid : {L, H}, bits : {, }}] does not have a declared label.

Opinion:
File secure-chisel3/src/main/scala/chisel3/util/Decoupled.scala defines the interface:

  val ready = Input(Bool(), rdyl)
  val valid = Output(Bool(), vall)
  val bits = Output(gen.chiselCloneType)

In the definition, bits inherits the data type from gen, but I think chiselCloneType method does not inherits the label information. Possible solution is val bits = Output(gen.chiselCloneType, gen.lbl_)?

At least in 1 instance, the generated firrtl has the wrong declaration for a label.
In the attached case, the InsnLookup module has the wrong label on its output. It should be taken from the other output wires (out_conf and out_int).

Instead, in the generated firrtl it uses the instantiation of InsnLookup (named icache) for the confidentiality.
debug.zip