Must define cfi_panic_handler and CFI_STATE_ORG in C code

Frankly, I don't know how the code was compiling before, but I suppose
Rust must have either accidentally left the symbols in the `.a` file?

Also we need to pass non-nil ICCM and DCCM pointers in Go code to Rust,
as Rust now will panic if nil slices are constructed, even if they have
length 0.

hw-model/c-binding/Cargo.toml

@@ -6,6 +6,7 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
+caliptra-cfi-lib.workspace = true
 caliptra-emu-bus.workspace = true
 caliptra-emu-types.workspace = true
 caliptra-hw-model.workspace = true
@@ -19,4 +20,4 @@ itrng = ["caliptra-hw-model/itrng"]
 verilator = ["caliptra-hw-model/verilator"]
 
 [build-dependencies]
-cbindgen.workspace = true
+cbindgen.workspace = true

hw-model/c-binding/src/caliptra_model.rs

@@ -1,13 +1,25 @@
 // Licensed under the Apache-2.0 license
 
 use caliptra_api::soc_mgr::SocManager;
+use caliptra_cfi_lib::CfiState;
 use caliptra_emu_bus::Bus;
 use caliptra_hw_model::{DefaultHwModel, HwModel, InitParams, SecurityState};
 use std::ffi::*;
 use std::slice;
 
 use caliptra_emu_types::RvSize;
 
+// These are needed if CFI is enabled.
+#[no_mangle]
+pub extern "C" fn cfi_panic_handler(code: u32) -> ! {
+    std::process::exit(code as i32);
+}
+
+#[allow(unused)]
+#[no_mangle]
+static mut CFI_STATE_ORG: [u8; std::mem::size_of::<CfiState>()] =
+    [0; std::mem::size_of::<CfiState>()];
+
 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
 pub struct caliptra_model {

test/dpe_verification/transport.go

@@ -43,7 +43,6 @@ static int set_fuses()
     }
     return status;
 }
-
 */
 import "C"
 
@@ -111,6 +110,16 @@ func getHWModel() *C.struct_caliptra_model {
 	params.rom.data = (*C.uchar)(cRom)
 	params.rom.len = C.uintptr_t(len(rom))
 
+	// use a dummy value for iccm and dccm because they have to be non-nil
+	iccm := C.CBytes([]byte{0})
+	defer C.free(iccm)
+	params.iccm.data = (*C.uchar)(iccm)
+	params.iccm.len = C.uintptr_t(0)
+	dccm := C.CBytes([]byte{0})
+	defer C.free(dccm)
+	params.dccm.data = (*C.uchar)(dccm)
+	params.dccm.len = C.uintptr_t(0)
+
 	status := C.caliptra_model_init_default(params, &CaliptraCModel)
 	if status != 0 {
 		panic("Failed to initialize caliptra model")