unicorn running without a working oracle

minigeth/oracle/embedded_mips.go

@@ -11,6 +11,7 @@ import (
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/crypto"
 )
 
 var preimages = make(map[common.Hash][]byte)
@@ -78,11 +79,11 @@ func Preimage(hash common.Hash) []byte {
 		size := (int(rawSize[0]) << 24) | (int(rawSize[1]) << 16) | (int(rawSize[2]) << 8) | int(rawSize[3])
 		ret := common.CopyBytes(byteAt(0x31000004, size))
 
-		// this is 20% of the exec instructions
-		/*realhash := crypto.Keccak256Hash(ret)
+		// this is 20% of the exec instructions, this speedup is always an option
+		realhash := crypto.Keccak256Hash(ret)
 		if realhash != hash {
 			panic("preimage has wrong hash")
-		}*/
+		}
 
 		preimages[hash] = ret
 		return ret

mipsevm/unicorn.go

@@ -4,6 +4,8 @@ import (
 	"fmt"
 	"io/ioutil"
 	"log"
+	"os"
+	"time"
 
 	uc "github.com/unicorn-engine/unicorn/bindings/go/unicorn"
 )
@@ -15,6 +17,11 @@ func check(err error) {
 }
 
 var steps int = 0
+var heap_start uint64 = 0
+
+func RegRead(u *uc.Unicorn, reg int) {
+
+}
 
 func RunUnicorn(fn string) {
 	mu, err := uc.NewUnicorn(uc.ARCH_MIPS, uc.MODE_32|uc.MODE_BIG_ENDIAN)
@@ -22,15 +29,40 @@ func RunUnicorn(fn string) {
 
 	mu.HookAdd(uc.HOOK_INTR, func(mu uc.Unicorn, intno uint32) {
 		if intno != 17 {
-			log.Fatal("invalid interrupt ", intno)
+			log.Fatal("invalid interrupt ", intno, " at step ", steps)
 		}
 		syscall_no, _ := mu.RegRead(uc.MIPS_REG_V0)
-		fmt.Println("syscall", syscall_no)
+		v0 := uint64(0)
+		if syscall_no == 4004 {
+			buf, _ := mu.RegRead(uc.MIPS_REG_A1)
+			count, _ := mu.RegRead(uc.MIPS_REG_A2)
+			bytes, _ := mu.MemRead(buf, count)
+			os.Stderr.Write(bytes)
+		} else if syscall_no == 4090 {
+			a0, _ := mu.RegRead(uc.MIPS_REG_A0)
+			sz, _ := mu.RegRead(uc.MIPS_REG_A1)
+			if a0 == 0 {
+				v0 = 0x20000000 + heap_start
+				heap_start += sz
+			} else {
+				v0 = a0
+			}
+		} else if syscall_no == 4045 {
+			v0 = 0x40000000
+		} else if syscall_no == 4120 {
+			v0 = 1
+		} else {
+			fmt.Println("syscall", syscall_no)
+		}
+		mu.RegWrite(uc.MIPS_REG_V0, v0)
+		mu.RegWrite(uc.MIPS_REG_A3, 0)
 	}, 1, 0)
 
+	ministart := time.Now()
 	mu.HookAdd(uc.HOOK_CODE, func(mu uc.Unicorn, addr uint64, size uint32) {
-		if steps%10000 == 0 {
-			fmt.Printf("%6d Code: 0x%x, 0x%x\n", steps, addr, size)
+		if steps%100000 == 0 {
+			steps_per_sec := float64(steps) * 1e9 / float64(time.Now().Sub(ministart).Nanoseconds())
+			fmt.Printf("%6d Code: 0x%x, 0x%x steps per s %f\n", steps, addr, size, steps_per_sec)
 		}
 		steps += 1
 	}, 1, 0)