add local support for introspection service

Signed-off-by: Kathryn Baldauf <kabaldau@microsoft.com>

vendor/github.com/cilium/ebpf/asm/load_store.go

@@ -0,0 +1,189 @@
+package asm
+
+//go:generate stringer -output load_store_string.go -type=Mode,Size
+
+// Mode for load and store operations
+//
+//    msb      lsb
+//    +---+--+---+
+//    |MDE|sz|cls|
+//    +---+--+---+
+type Mode uint8
+
+const modeMask OpCode = 0xe0
+
+const (
+	// InvalidMode is returned by getters when invoked
+	// on non load / store OpCodes
+	InvalidMode Mode = 0xff
+	// ImmMode - immediate value
+	ImmMode Mode = 0x00
+	// AbsMode - immediate value + offset
+	AbsMode Mode = 0x20
+	// IndMode - indirect (imm+src)
+	IndMode Mode = 0x40
+	// MemMode - load from memory
+	MemMode Mode = 0x60
+	// XAddMode - add atomically across processors.
+	XAddMode Mode = 0xc0
+)
+
+// Size of load and store operations
+//
+//    msb      lsb
+//    +---+--+---+
+//    |mde|SZ|cls|
+//    +---+--+---+
+type Size uint8
+
+const sizeMask OpCode = 0x18
+
+const (
+	// InvalidSize is returned by getters when invoked
+	// on non load / store OpCodes
+	InvalidSize Size = 0xff
+	// DWord - double word; 64 bits
+	DWord Size = 0x18
+	// Word - word; 32 bits
+	Word Size = 0x00
+	// Half - half-word; 16 bits
+	Half Size = 0x08
+	// Byte - byte; 8 bits
+	Byte Size = 0x10
+)
+
+// Sizeof returns the size in bytes.
+func (s Size) Sizeof() int {
+	switch s {
+	case DWord:
+		return 8
+	case Word:
+		return 4
+	case Half:
+		return 2
+	case Byte:
+		return 1
+	default:
+		return -1
+	}
+}
+
+// LoadMemOp returns the OpCode to load a value of given size from memory.
+func LoadMemOp(size Size) OpCode {
+	return OpCode(LdXClass).SetMode(MemMode).SetSize(size)
+}
+
+// LoadMem emits `dst = *(size *)(src + offset)`.
+func LoadMem(dst, src Register, offset int16, size Size) Instruction {
+	return Instruction{
+		OpCode: LoadMemOp(size),
+		Dst:    dst,
+		Src:    src,
+		Offset: offset,
+	}
+}
+
+// LoadImmOp returns the OpCode to load an immediate of given size.
+//
+// As of kernel 4.20, only DWord size is accepted.
+func LoadImmOp(size Size) OpCode {
+	return OpCode(LdClass).SetMode(ImmMode).SetSize(size)
+}
+
+// LoadImm emits `dst = (size)value`.
+//
+// As of kernel 4.20, only DWord size is accepted.
+func LoadImm(dst Register, value int64, size Size) Instruction {
+	return Instruction{
+		OpCode:   LoadImmOp(size),
+		Dst:      dst,
+		Constant: value,
+	}
+}
+
+// LoadMapPtr stores a pointer to a map in dst.
+func LoadMapPtr(dst Register, fd int) Instruction {
+	if fd < 0 {
+		return Instruction{OpCode: InvalidOpCode}
+	}
+
+	return Instruction{
+		OpCode:   LoadImmOp(DWord),
+		Dst:      dst,
+		Src:      R1,
+		Constant: int64(fd),
+	}
+}
+
+// LoadIndOp returns the OpCode for loading a value of given size from an sk_buff.
+func LoadIndOp(size Size) OpCode {
+	return OpCode(LdClass).SetMode(IndMode).SetSize(size)
+}
+
+// LoadInd emits `dst = ntoh(*(size *)(((sk_buff *)R6)->data + src + offset))`.
+func LoadInd(dst, src Register, offset int32, size Size) Instruction {
+	return Instruction{
+		OpCode:   LoadIndOp(size),
+		Dst:      dst,
+		Src:      src,
+		Constant: int64(offset),
+	}
+}
+
+// LoadAbsOp returns the OpCode for loading a value of given size from an sk_buff.
+func LoadAbsOp(size Size) OpCode {
+	return OpCode(LdClass).SetMode(AbsMode).SetSize(size)
+}
+
+// LoadAbs emits `r0 = ntoh(*(size *)(((sk_buff *)R6)->data + offset))`.
+func LoadAbs(offset int32, size Size) Instruction {
+	return Instruction{
+		OpCode:   LoadAbsOp(size),
+		Dst:      R0,
+		Constant: int64(offset),
+	}
+}
+
+// StoreMemOp returns the OpCode for storing a register of given size in memory.
+func StoreMemOp(size Size) OpCode {
+	return OpCode(StXClass).SetMode(MemMode).SetSize(size)
+}
+
+// StoreMem emits `*(size *)(dst + offset) = src`
+func StoreMem(dst Register, offset int16, src Register, size Size) Instruction {
+	return Instruction{
+		OpCode: StoreMemOp(size),
+		Dst:    dst,
+		Src:    src,
+		Offset: offset,
+	}
+}
+
+// StoreImmOp returns the OpCode for storing an immediate of given size in memory.
+func StoreImmOp(size Size) OpCode {
+	return OpCode(StClass).SetMode(MemMode).SetSize(size)
+}
+
+// StoreImm emits `*(size *)(dst + offset) = value`.
+func StoreImm(dst Register, offset int16, value int64, size Size) Instruction {
+	return Instruction{
+		OpCode:   StoreImmOp(size),
+		Dst:      dst,
+		Offset:   offset,
+		Constant: value,
+	}
+}
+
+// StoreXAddOp returns the OpCode to atomically add a register to a value in memory.
+func StoreXAddOp(size Size) OpCode {
+	return OpCode(StXClass).SetMode(XAddMode).SetSize(size)
+}
+
+// StoreXAdd atomically adds src to *dst.
+func StoreXAdd(dst, src Register, size Size) Instruction {
+	return Instruction{
+		OpCode: StoreXAddOp(size),
+		Dst:    dst,
+		Src:    src,
+	}
+}