overhaul syscall description generation process

This splits generation process into two phases:
1. Extract values of constants from linux kernel sources.
2. Generate Go code.

Constant values are checked in.
The advantage is that the second phase is now completely independent
from linux source files, kernel version, presence of headers for
particular drivers, etc. This allows to change what Go code we generate
any time without access to all kernel headers (which in future won't be
limited to only upstream headers).

Constant extraction process does require proper kernel sources,
but this can be done only once by the person who added the driver
and has access to the required sources. Then the constant values
are checked in for others to use.
Consant extraction process is per-file/per-arch. That is,
if I am adding a driver that is not present upstream and that
works only on a single arch, I will check in constants only for
that driver and for that arch.

1 files changed, 11 insertions, 11 deletions

diff --git a/prog/analysis.go b/prog/analysis.go
index 100c2febe..9f5222b17 100644
--- a/prog/analysis.go
+++ b/prog/analysis.go
@@ -75,7 +75,7 @@ func (s *state) analyze(c *Call) {
 		if length.AddrPage == 0 && length.AddrOffset == 0 {
 			break
 		}
-		if flags, fd := c.Args[4], c.Args[3]; flags.Val&MAP_ANONYMOUS == 0 && fd.Kind == ArgConst && fd.Val == sys.InvalidFD {
+		if flags, fd := c.Args[4], c.Args[3]; flags.Val&sys.MAP_ANONYMOUS == 0 && fd.Kind == ArgConst && fd.Val == sys.InvalidFD {
 			break
 		}
 		s.addressable(c.Args[0], length, true)
@@ -237,15 +237,15 @@ func sanitizeCall(c *Call) {
 		if flags.Kind != ArgConst {
 			panic("mmap flag arg is not const")
 		}
-		flags.Val |= MAP_FIXED
+		flags.Val |= sys.MAP_FIXED
 	case "mremap":
 		// Add MREMAP_FIXED flag, otherwise it produces non-deterministic results.
 		flags := c.Args[3]
 		if flags.Kind != ArgConst {
 			panic("mremap flag arg is not const")
 		}
-		if flags.Val&MREMAP_MAYMOVE != 0 {
-			flags.Val |= MREMAP_FIXED
+		if flags.Val&sys.MREMAP_MAYMOVE != 0 {
+			flags.Val |= sys.MREMAP_FIXED
 		}
 	case "mknod":
 		mode := c.Args[1]
@@ -254,27 +254,27 @@ func sanitizeCall(c *Call) {
 		}
 		// Char and block devices read/write io ports, kernel memory and do other nasty things.
 		// TODO: not required if executor drops privileges.
-		if mode.Val != S_IFREG && mode.Val != S_IFIFO && mode.Val != S_IFSOCK {
-			mode.Val = S_IFIFO
+		if mode.Val != sys.S_IFREG && mode.Val != sys.S_IFIFO && mode.Val != sys.S_IFSOCK {
+			mode.Val = sys.S_IFIFO
 		}
 	case "syslog":
 		cmd := c.Args[0]
 		// These disable console output, but we need it.
-		if cmd.Val == SYSLOG_ACTION_CONSOLE_OFF || cmd.Val == SYSLOG_ACTION_CONSOLE_ON {
-			cmd.Val = SYSLOG_ACTION_SIZE_UNREAD
+		if cmd.Val == sys.SYSLOG_ACTION_CONSOLE_OFF || cmd.Val == sys.SYSLOG_ACTION_CONSOLE_ON {
+			cmd.Val = sys.SYSLOG_ACTION_SIZE_UNREAD
 		}
 	case "ioctl":
 		cmd := c.Args[1]
 		// Freeze kills machine. Though, it is an interesting functions,
 		// so we need to test it somehow.
 		// TODO: not required if executor drops privileges.
-		if uint32(cmd.Val) == uint32(FIFREEZE) {
-			cmd.Val = FITHAW
+		if uint32(cmd.Val) == sys.FIFREEZE {
+			cmd.Val = sys.FITHAW
 		}
 	case "ptrace":
 		// PTRACE_TRACEME leads to unkillable processes, see:
 		// https://groups.google.com/forum/#!topic/syzkaller/uGzwvhlCXAw
-		if c.Args[0].Val == PTRACE_TRACEME {
+		if c.Args[0].Val == sys.PTRACE_TRACEME {
 			c.Args[0].Val = ^uintptr(0)
 		}
 	case "exit", "exit_group":