macaw-riscv: Add riscvPLTStubInfo

Now that we can load RISC-V relocations in `macaw` (building on top of the work
in GaloisInc/elf-edit#45), this patch adds PLT stub heuristics for RISC-V
binaries. I have added some test cases in `macaw-riscv-symbolic` which
demonstrate that the basic idea works.

Note that due to #416, these test cases will print warnings when loaded into
`macaw`. These warnings are ultimately harmless, however, as the same
relocations are loaded at the same addresses multiple times, which causes no
change in behavior.

Fixes #414.

Author: RyanGlScott

macaw-riscv-symbolic/tests/Main.hs

@@ -32,7 +32,6 @@ import qualified Test.Tasty.Runners as TTR
 import qualified Data.Macaw.Architecture.Info as MAI
 import qualified Data.Macaw.CFG as MC
 import qualified Data.Macaw.Discovery as M
-import qualified Data.Macaw.Memory.ElfLoader.PLTStubs as MMELP
 import qualified Data.Macaw.Symbolic as MS
 import qualified Data.Macaw.Symbolic.Testing as MST
 import qualified Data.Macaw.RISCV as MR
@@ -133,8 +132,8 @@ symExTestSized :: forall rv w arch
                   , 16 <= w
                   , MC.ArchConstraints arch
                   , arch ~ MR.RISCV rv
+                  , Elf.ElfWidthConstraints w
                   , KnownNat w
-                  , Show (Elf.ElfWordType w)
                   , MS.ArchInfo arch
                   )
                => MST.SimulationResult
@@ -147,12 +146,7 @@ symExTestSized :: forall rv w arch
                -> MAI.ArchitectureInfo arch
                -> TTH.Assertion
 symExTestSized expected mmPreset exePath saveSMT saveMacaw step ehi archInfo = do
-   binfo <- MST.runDiscovery ehi exePath MST.toAddrSymMap archInfo
-                             -- Test cases involving shared libraries are not
-                             -- yet supported on the RISC-V backend. At a
-                             -- minimum, this is blocked on
-                             -- https://github.com/GaloisInc/elf-edit/issues/36.
-                             (MMELP.noPLTStubInfo "RISC-V")
+   binfo <- MST.runDiscovery ehi exePath MST.toAddrSymMap archInfo MR.riscvPLTStubInfo
    let funInfos = Map.elems (MST.binaryDiscState (MST.mainBinaryInfo binfo) ^. M.funInfo)
    let testEntryPoints = mapMaybe hasTestPrefix funInfos
    F.forM_ testEntryPoints $ \(name, Some dfi) -> do

macaw-riscv-symbolic/tests/pass/Makefile

@@ -2,6 +2,7 @@
 CC64=riscv64-linux-musl-gcc
 CC32=riscv32-linux-musl-gcc
 CFLAGS=-nostdlib -no-pie -static -fno-stack-protector
+SO_CFLAGS=-nostdlib -fno-stack-protector -fcf-protection=none
 
 unopt32 = $(patsubst %.c,%.unopt32.exe,$(wildcard *.c))
 unopt64 = $(patsubst %.c,%.unopt64.exe,$(wildcard *.c))
@@ -21,3 +22,33 @@ all: $(unopt32) $(opt32) $(unopt64) $(opt64)
 
 %.opt64.exe : %.c
 	$(CC64) $(CFLAGS) -O2 $< -o $@
+
+so/libfib.unopt32.so: so/fib.c so/libgetone.unopt32.so
+	$(CC32) $(SO_CFLAGS) -O0 -Lso/ -Iso/ -shared $< -lgetone.unopt32 -o $@
+so/libfib.opt32.so: so/fib.c so/libgetone.opt32.so
+	$(CC32) $(SO_CFLAGS) -O2 -Lso/ -Iso/ -shared $< -lgetone.opt32 -o $@
+
+so/libgetone.unopt32.so : so/getone.c
+	$(CC32) $(SO_CFLAGS) -O0 -Iso/ -shared $< -o $@
+so/libgetone.opt32.so : so/getone.c
+	$(CC32) $(SO_CFLAGS) -O2 -Iso/ -shared $< -o $@
+
+so/so.unopt32.exe : so/so.c so/libfib.unopt32.so
+	$(CC32) $(SO_CFLAGS) -O0 -Lso/ -Iso/ $< -lfib.unopt32 -lgetone.unopt32 -o $@
+so/so.opt32.exe : so/so.c so/libfib.opt32.so
+	$(CC32) $(SO_CFLAGS) -O2 -Lso/ -Iso/ $< -lfib.opt32 -lgetone.opt32 -o $@
+
+so/libfib.unopt64.so: so/fib.c so/libgetone.unopt64.so
+	$(CC64) $(SO_CFLAGS) -O0 -Lso/ -Iso/ -shared $< -lgetone.unopt64 -o $@
+so/libfib.opt64.so: so/fib.c so/libgetone.opt64.so
+	$(CC64) $(SO_CFLAGS) -O2 -Lso/ -Iso/ -shared $< -lgetone.opt64 -o $@
+
+so/libgetone.unopt64.so : so/getone.c
+	$(CC64) $(SO_CFLAGS) -O0 -Iso/ -shared $< -o $@
+so/libgetone.opt64.so : so/getone.c
+	$(CC64) $(SO_CFLAGS) -O2 -Iso/ -shared $< -o $@
+
+so/so.unopt64.exe : so/so.c so/libfib.unopt64.so
+	$(CC64) $(SO_CFLAGS) -O0 -Lso/ -Iso/ $< -lfib.unopt64 -lgetone.unopt64 -o $@
+so/so.opt64.exe : so/so.c so/libfib.opt64.so
+	$(CC64) $(SO_CFLAGS) -O2 -Lso/ -Iso/ $< -lfib.opt64 -lgetone.opt64 -o $@

macaw-riscv-symbolic/tests/pass/so/fib.c

@@ -0,0 +1,8 @@
+#include "fib.h"
+#include "getone.h"
+
+int fib(int n) {
+  if (n <= 0) return 0;
+  if (n == 1) return getone();
+  return fib(n - 1) + fib(n - 2);
+}

macaw-riscv-symbolic/tests/pass/so/fib.h

@@ -0,0 +1 @@
+int fib(int x);

macaw-riscv-symbolic/tests/pass/so/getone.c

@@ -0,0 +1,5 @@
+#include "getone.h"
+
+int getone(void) {
+  return 1;
+}

macaw-riscv-symbolic/tests/pass/so/getone.h

@@ -0,0 +1 @@
+int getone(void);

macaw-riscv-symbolic/tests/pass/so/libfib.opt32.so

@@ -0,0 +1,9 @@
+#include "fib.h"
+
+int __attribute__((noinline)) test_fib(void) {
+  return fib(6) == 8;
+}
+
+void _start(void) {
+  test_fib();
+}

macaw-riscv-symbolic/tests/pass/so/libfib.opt64.so

@@ -25,6 +25,7 @@ library
                        bv-sized,
                        bytestring,
                        containers,
+                       elf-edit,
                        grift,
                        lens,
                        macaw-base,

macaw-riscv-symbolic/tests/pass/so/libfib.unopt32.so

@@ -12,6 +12,7 @@ module Data.Macaw.RISCV (
   module Data.Macaw.RISCV.RISCVReg,
   -- * Macaw configurations
   riscv_info,
+  riscvPLTStubInfo,
   -- * Type-level tags
   G.RV(..),
   G.RVRepr(..),
@@ -25,10 +26,12 @@ module Data.Macaw.RISCV (
 
 import GHC.Stack (HasCallStack)
 
+import qualified Data.ElfEdit as EE
 import qualified Data.Macaw.CFG as MC
 import qualified Data.Macaw.CFG.DemandSet as MD
 import           Data.Macaw.Discovery ( defaultClassifier )
 import qualified Data.Macaw.Architecture.Info as MI
+import qualified Data.Macaw.Memory.ElfLoader.PLTStubs as MMEP
 import Data.Parameterized ( type(<=) )
 import qualified GRIFT.Types as G
 
@@ -79,3 +82,11 @@ riscv_info rvRepr =
         , MI.postArchTermStmtAbsState = \_ _ _ _ _ -> error $ "postArchTermStmtAbsState unimplemented in riscv_info"
         , MI.archClassifier = defaultClassifier
         }
+
+-- | PLT stub information for ARM32 relocation types.
+riscvPLTStubInfo :: MMEP.PLTStubInfo (EE.RISCV_RelocationType w)
+riscvPLTStubInfo = MMEP.PLTStubInfo
+  { MMEP.pltFunSize     = 32
+  , MMEP.pltStubSize    = 16
+  , MMEP.pltGotStubSize = error "Unexpected .plt.got section in RISC-V binary"
+  }