executor: add network packet injection for NetBSD

* Initial Commit

* working build of network packet fuzzing

* Add missed csource file

* pkg/csource: fix build

* executor/common_bsd.h: Add comment stating reason for ifconfig create

2 files changed, 36 insertions, 1 deletions

diff --git a/sys/netbsd/gen/amd64.go b/sys/netbsd/gen/amd64.go
index a1d0e49cc..8697d5f7e 100644
--- a/sys/netbsd/gen/amd64.go
+++ b/sys/netbsd/gen/amd64.go
@@ -26,6 +26,7 @@ var resources_amd64 = []*ResourceDesc{
 	{Name: "sock_in", Type: &IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", TypeSize: 4}}}, Kind: []string{"fd", "sock", "sock_in"}, Values: []uint64{18446744073709551615, 18446744073709551516}},
 	{Name: "sock_in6", Type: &IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", TypeSize: 4}}}, Kind: []string{"fd", "sock", "sock_in6"}, Values: []uint64{18446744073709551615, 18446744073709551516}},
 	{Name: "sock_unix", Type: &IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", TypeSize: 4}}}, Kind: []string{"fd", "sock", "sock_unix"}, Values: []uint64{18446744073709551615, 18446744073709551516}},
+	{Name: "tcp_seq_num", Type: &IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", TypeSize: 4}}}, Kind: []string{"tcp_seq_num"}, Values: []uint64{1094861636}},
 	{Name: "uid", Type: &IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", TypeSize: 4}}}, Kind: []string{"uid"}, Values: []uint64{0, 18446744073709551615}},
 }
 
@@ -344,6 +345,10 @@ var structDescs_amd64 = []*KeyedStruct{
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "pad1", TypeSize: 4, ArgDir: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "pad2", TypeSize: 4, ArgDir: 1}}},
 	}}},
+	{Key: StructKey{Name: "tcp_resources", Dir: 1}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "tcp_resources", TypeSize: 8, ArgDir: 1}, Fields: []Type{
+		&ResourceType{TypeCommon: TypeCommon{TypeName: "tcp_seq_num", FldName: "seq", TypeSize: 4, ArgDir: 1}},
+		&ResourceType{TypeCommon: TypeCommon{TypeName: "tcp_seq_num", FldName: "ack", TypeSize: 4, ArgDir: 1}},
+	}}},
 	{Key: StructKey{Name: "timespec"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "timespec", TypeSize: 16}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "intptr", FldName: "sec", TypeSize: 8}}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "intptr", FldName: "nsec", TypeSize: 8}}},
@@ -1347,9 +1352,23 @@ var syscalls_amd64 = []*Syscall{
 		&PtrType{TypeCommon: TypeCommon{TypeName: "ptr", FldName: "new", TypeSize: 8}, Type: &BufferType{TypeCommon: TypeCommon{TypeName: "filename", IsVarlen: true}, Kind: 3}},
 	}},
 	{NR: 36, Name: "sync", CallName: "sync"},
+	{Name: "syz_emit_ethernet", CallName: "syz_emit_ethernet", Args: []Type{
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "len", TypeSize: 8}}, Path: []string{"packet"}},
+		&PtrType{TypeCommon: TypeCommon{TypeName: "ptr", FldName: "packet", TypeSize: 8}, Type: &BufferType{TypeCommon: TypeCommon{TypeName: "array", IsVarlen: true}}},
+	}},
 	{Name: "syz_execute_func", CallName: "syz_execute_func", Args: []Type{
 		&PtrType{TypeCommon: TypeCommon{TypeName: "ptr", FldName: "text", TypeSize: 8}, Type: &BufferType{TypeCommon: TypeCommon{TypeName: "text", IsVarlen: true}, Kind: 4}},
 	}},
+	{Name: "syz_extract_tcp_res", CallName: "syz_extract_tcp_res", Args: []Type{
+		&PtrType{TypeCommon: TypeCommon{TypeName: "ptr", FldName: "res", TypeSize: 8}, Type: &StructType{Key: StructKey{Name: "tcp_resources", Dir: 1}}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "seq_inc", TypeSize: 4}}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "ack_inc", TypeSize: 4}}},
+	}},
+	{Name: "syz_extract_tcp_res$synack", CallName: "syz_extract_tcp_res", Args: []Type{
+		&PtrType{TypeCommon: TypeCommon{TypeName: "ptr", FldName: "res", TypeSize: 8}, Type: &StructType{Key: StructKey{Name: "tcp_resources", Dir: 1}}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "seq_inc", TypeSize: 8}}, Val: 1},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "const", FldName: "ack_inc", TypeSize: 8}}},
+	}},
 	{NR: 200, Name: "truncate", CallName: "truncate", Args: []Type{
 		&PtrType{TypeCommon: TypeCommon{TypeName: "ptr", FldName: "file", TypeSize: 8}, Type: &BufferType{TypeCommon: TypeCommon{TypeName: "filename", IsVarlen: true}, Kind: 3}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "intptr", FldName: "len", TypeSize: 8}}},
@@ -1791,4 +1810,4 @@ var consts_amd64 = []ConstValue{
 	{Name: "_UC_STACK", Value: 2},
 }
 
-const revision_amd64 = "71ea2d6047354a28057976d7ea40a5f24673a27c"
+const revision_amd64 = "65d5b75dae9655ed21ef93383407c6108cf4de62"
diff --git a/sys/netbsd/vnet.txt b/sys/netbsd/vnet.txt
new file mode 100644
index 000000000..0e9dbc53f
--- /dev/null
+++ b/sys/netbsd/vnet.txt
@@ -0,0 +1,16 @@
+# Copyright 2018 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.
+
+syz_emit_ethernet(len len[packet], packet ptr[in, array[int8]])
+
+resource tcp_seq_num[int32]: 0x41424344
+
+tcp_resources {
+	seq	tcp_seq_num
+	ack	tcp_seq_num
+}
+
+# These pseudo syscalls read a packet from tap device and extract tcp sequence and acknowledgement numbers from it.
+# They also adds the inc arguments to the returned values, this way sequence numbers get incremented.
+syz_extract_tcp_res(res ptr[out, tcp_resources], seq_inc int32, ack_inc int32)
+syz_extract_tcp_res$synack(res ptr[out, tcp_resources], seq_inc const[1], ack_inc const[0])