initial commit

1 files changed, 114 insertions, 0 deletions

diff --git a/prog/encodingc.go b/prog/encodingc.go
new file mode 100644
index 000000000..c84acc918
--- /dev/null
+++ b/prog/encodingc.go
@@ -0,0 +1,114 @@
+// Copyright 2015 syzkaller project authors. All rights reserved.
+// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
+
+package prog
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"unsafe"
+
+	"github.com/google/syzkaller/sys"
+)
+
+func (p *Prog) WriteCSource() []byte {
+	exec := p.SerializeForExec()
+	buf := new(bytes.Buffer)
+	writeCSource(buf, exec)
+	return buf.Bytes()
+}
+
+func writeCSource(w io.Writer, exec []byte) {
+	fmt.Fprintf(w, `// autogenerated by syzkaller (http://github.com/google/syzkaller)
+#include <syscall.h>
+#include <string.h>
+#include <stdint.h>
+
+int main()
+{
+`)
+	read := func() uintptr {
+		if len(exec) < 8 {
+			panic("exec program overflow")
+		}
+		v := *(*uint64)(unsafe.Pointer(&exec[0]))
+		exec = exec[8:]
+		return uintptr(v)
+	}
+	resultRef := func() string {
+		arg := read()
+		res := fmt.Sprintf("r%v", arg)
+		if opDiv := read(); opDiv != 0 {
+			res = fmt.Sprintf("%v/%v", res, opDiv)
+		}
+		if opAdd := read(); opAdd != 0 {
+			res = fmt.Sprintf("%v+%v", res, opAdd)
+		}
+		return res
+	}
+	lastCall := 0
+	for n := 0; ; n++ {
+		switch instr := read(); instr {
+		case instrEOF:
+			fmt.Fprintf(w, "\treturn 0;\n}\n")
+			return
+		case instrCopyin:
+			addr := read()
+			typ := read()
+			size := read()
+			switch typ {
+			case execArgConst:
+				arg := read()
+				fmt.Fprintf(w, "\t*(uint%v_t*)0x%x = 0x%x;\n", size*8, addr, arg)
+			case execArgResult:
+				fmt.Fprintf(w, "\t*(uint%v_t*)0x%x = %v;\n", size*8, addr, resultRef())
+			case execArgData:
+				data := exec[:size]
+				exec = exec[(size+7)/8*8:]
+				var esc []byte
+				for _, v := range data {
+					hex := func(v byte) byte {
+						if v < 10 {
+							return '0' + v
+						}
+						return 'a' + v - 10
+					}
+					esc = append(esc, '\\', 'x', hex(v>>4), hex(v<<4>>4))
+				}
+				fmt.Fprintf(w, "\tmemcpy((void*)0x%x, \"%s\", %v);\n", addr, esc, size)
+			default:
+				panic("bad argument type")
+			}
+		case instrCopyout:
+			addr := read()
+			size := read()
+			fmt.Fprintf(w, "\tlong r%v = -1;\n", n)
+			fmt.Fprintf(w, "\tif (r%v != -1)\n", lastCall)
+			fmt.Fprintf(w, "\t\tr%v = *(uint%v_t*)0x%x;\n", n, size*8, addr)
+		default:
+			// Normal syscall.
+			meta := sys.Calls[instr]
+			fmt.Fprintf(w, "\tlong r%v = syscall(SYS_%v", n, meta.CallName)
+			nargs := read()
+			for i := uintptr(0); i < nargs; i++ {
+				typ := read()
+				size := read()
+				_ = size
+				switch typ {
+				case execArgConst:
+					fmt.Fprintf(w, ", 0x%xul", read())
+				case execArgResult:
+					fmt.Fprintf(w, ", %v", resultRef())
+				default:
+					panic("unknown arg type")
+				}
+			}
+			for i := nargs; i < 6; i++ {
+				fmt.Fprintf(w, ", 0")
+			}
+			fmt.Fprintf(w, ");\n")
+			lastCall = n
+		}
+	}
+}