diff options
Diffstat (limited to 'vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf')
18 files changed, 3859 insertions, 0 deletions
diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/asm.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/asm.go new file mode 100644 index 000000000..15e21b181 --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/asm.go @@ -0,0 +1,41 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package bpf + +import "fmt" + +// Assemble converts insts into raw instructions suitable for loading +// into a BPF virtual machine. +// +// Currently, no optimization is attempted, the assembled program flow +// is exactly as provided. +func Assemble(insts []Instruction) ([]RawInstruction, error) { + ret := make([]RawInstruction, len(insts)) + var err error + for i, inst := range insts { + ret[i], err = inst.Assemble() + if err != nil { + return nil, fmt.Errorf("assembling instruction %d: %s", i+1, err) + } + } + return ret, nil +} + +// Disassemble attempts to parse raw back into +// Instructions. Unrecognized RawInstructions are assumed to be an +// extension not implemented by this package, and are passed through +// unchanged to the output. The allDecoded value reports whether insts +// contains no RawInstructions. +func Disassemble(raw []RawInstruction) (insts []Instruction, allDecoded bool) { + insts = make([]Instruction, len(raw)) + allDecoded = true + for i, r := range raw { + insts[i] = r.Disassemble() + if _, ok := insts[i].(RawInstruction); ok { + allDecoded = false + } + } + return insts, allDecoded +} diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/constants.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/constants.go new file mode 100644 index 000000000..b89ca3523 --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/constants.go @@ -0,0 +1,218 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package bpf + +// A Register is a register of the BPF virtual machine. +type Register uint16 + +const ( + // RegA is the accumulator register. RegA is always the + // destination register of ALU operations. + RegA Register = iota + // RegX is the indirection register, used by LoadIndirect + // operations. + RegX +) + +// An ALUOp is an arithmetic or logic operation. +type ALUOp uint16 + +// ALU binary operation types. +const ( + ALUOpAdd ALUOp = iota << 4 + ALUOpSub + ALUOpMul + ALUOpDiv + ALUOpOr + ALUOpAnd + ALUOpShiftLeft + ALUOpShiftRight + aluOpNeg // Not exported because it's the only unary ALU operation, and gets its own instruction type. + ALUOpMod + ALUOpXor +) + +// A JumpTest is a comparison operator used in conditional jumps. +type JumpTest uint16 + +// Supported operators for conditional jumps. +const ( + // K == A + JumpEqual JumpTest = iota + // K != A + JumpNotEqual + // K > A + JumpGreaterThan + // K < A + JumpLessThan + // K >= A + JumpGreaterOrEqual + // K <= A + JumpLessOrEqual + // K & A != 0 + JumpBitsSet + // K & A == 0 + JumpBitsNotSet +) + +// An Extension is a function call provided by the kernel that +// performs advanced operations that are expensive or impossible +// within the BPF virtual machine. +// +// Extensions are only implemented by the Linux kernel. +// +// TODO: should we prune this list? Some of these extensions seem +// either broken or near-impossible to use correctly, whereas other +// (len, random, ifindex) are quite useful. +type Extension int + +// Extension functions available in the Linux kernel. +const ( + // extOffset is the negative maximum number of instructions used + // to load instructions by overloading the K argument. + extOffset = -0x1000 + // ExtLen returns the length of the packet. + ExtLen Extension = 1 + // ExtProto returns the packet's L3 protocol type. + ExtProto Extension = 0 + // ExtType returns the packet's type (skb->pkt_type in the kernel) + // + // TODO: better documentation. How nice an API do we want to + // provide for these esoteric extensions? + ExtType Extension = 4 + // ExtPayloadOffset returns the offset of the packet payload, or + // the first protocol header that the kernel does not know how to + // parse. + ExtPayloadOffset Extension = 52 + // ExtInterfaceIndex returns the index of the interface on which + // the packet was received. + ExtInterfaceIndex Extension = 8 + // ExtNetlinkAttr returns the netlink attribute of type X at + // offset A. + ExtNetlinkAttr Extension = 12 + // ExtNetlinkAttrNested returns the nested netlink attribute of + // type X at offset A. + ExtNetlinkAttrNested Extension = 16 + // ExtMark returns the packet's mark value. + ExtMark Extension = 20 + // ExtQueue returns the packet's assigned hardware queue. + ExtQueue Extension = 24 + // ExtLinkLayerType returns the packet's hardware address type + // (e.g. Ethernet, Infiniband). + ExtLinkLayerType Extension = 28 + // ExtRXHash returns the packets receive hash. + // + // TODO: figure out what this rxhash actually is. + ExtRXHash Extension = 32 + // ExtCPUID returns the ID of the CPU processing the current + // packet. + ExtCPUID Extension = 36 + // ExtVLANTag returns the packet's VLAN tag. + ExtVLANTag Extension = 44 + // ExtVLANTagPresent returns non-zero if the packet has a VLAN + // tag. + // + // TODO: I think this might be a lie: it reads bit 0x1000 of the + // VLAN header, which changed meaning in recent revisions of the + // spec - this extension may now return meaningless information. + ExtVLANTagPresent Extension = 48 + // ExtVLANProto returns 0x8100 if the frame has a VLAN header, + // 0x88a8 if the frame has a "Q-in-Q" double VLAN header, or some + // other value if no VLAN information is present. + ExtVLANProto Extension = 60 + // ExtRand returns a uniformly random uint32. + ExtRand Extension = 56 +) + +// The following gives names to various bit patterns used in opcode construction. + +const ( + opMaskCls uint16 = 0x7 + // opClsLoad masks + opMaskLoadDest = 0x01 + opMaskLoadWidth = 0x18 + opMaskLoadMode = 0xe0 + // opClsALU + opMaskOperandSrc = 0x08 + opMaskOperator = 0xf0 + // opClsJump + opMaskJumpConst = 0x0f + opMaskJumpCond = 0xf0 +) + +const ( + // +---------------+-----------------+---+---+---+ + // | AddrMode (3b) | LoadWidth (2b) | 0 | 0 | 0 | + // +---------------+-----------------+---+---+---+ + opClsLoadA uint16 = iota + // +---------------+-----------------+---+---+---+ + // | AddrMode (3b) | LoadWidth (2b) | 0 | 0 | 1 | + // +---------------+-----------------+---+---+---+ + opClsLoadX + // +---+---+---+---+---+---+---+---+ + // | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | + // +---+---+---+---+---+---+---+---+ + opClsStoreA + // +---+---+---+---+---+---+---+---+ + // | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | + // +---+---+---+---+---+---+---+---+ + opClsStoreX + // +---------------+-----------------+---+---+---+ + // | Operator (4b) | OperandSrc (1b) | 1 | 0 | 0 | + // +---------------+-----------------+---+---+---+ + opClsALU + // +-----------------------------+---+---+---+---+ + // | TestOperator (4b) | 0 | 1 | 0 | 1 | + // +-----------------------------+---+---+---+---+ + opClsJump + // +---+-------------------------+---+---+---+---+ + // | 0 | 0 | 0 | RetSrc (1b) | 0 | 1 | 1 | 0 | + // +---+-------------------------+---+---+---+---+ + opClsReturn + // +---+-------------------------+---+---+---+---+ + // | 0 | 0 | 0 | TXAorTAX (1b) | 0 | 1 | 1 | 1 | + // +---+-------------------------+---+---+---+---+ + opClsMisc +) + +const ( + opAddrModeImmediate uint16 = iota << 5 + opAddrModeAbsolute + opAddrModeIndirect + opAddrModeScratch + opAddrModePacketLen // actually an extension, not an addressing mode. + opAddrModeMemShift +) + +const ( + opLoadWidth4 uint16 = iota << 3 + opLoadWidth2 + opLoadWidth1 +) + +// Operator defined by ALUOp* + +const ( + opALUSrcConstant uint16 = iota << 3 + opALUSrcX +) + +const ( + opJumpAlways = iota << 4 + opJumpEqual + opJumpGT + opJumpGE + opJumpSet +) + +const ( + opRetSrcConstant uint16 = iota << 4 + opRetSrcA +) + +const ( + opMiscTAX = 0x00 + opMiscTXA = 0x80 +) diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/doc.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/doc.go new file mode 100644 index 000000000..ae62feb53 --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/doc.go @@ -0,0 +1,82 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +/* + +Package bpf implements marshaling and unmarshaling of programs for the +Berkeley Packet Filter virtual machine, and provides a Go implementation +of the virtual machine. + +BPF's main use is to specify a packet filter for network taps, so that +the kernel doesn't have to expensively copy every packet it sees to +userspace. However, it's been repurposed to other areas where running +user code in-kernel is needed. For example, Linux's seccomp uses BPF +to apply security policies to system calls. For simplicity, this +documentation refers only to packets, but other uses of BPF have their +own data payloads. + +BPF programs run in a restricted virtual machine. It has almost no +access to kernel functions, and while conditional branches are +allowed, they can only jump forwards, to guarantee that there are no +infinite loops. + +The virtual machine + +The BPF VM is an accumulator machine. Its main register, called +register A, is an implicit source and destination in all arithmetic +and logic operations. The machine also has 16 scratch registers for +temporary storage, and an indirection register (register X) for +indirect memory access. All registers are 32 bits wide. + +Each run of a BPF program is given one packet, which is placed in the +VM's read-only "main memory". LoadAbsolute and LoadIndirect +instructions can fetch up to 32 bits at a time into register A for +examination. + +The goal of a BPF program is to produce and return a verdict (uint32), +which tells the kernel what to do with the packet. In the context of +packet filtering, the returned value is the number of bytes of the +packet to forward to userspace, or 0 to ignore the packet. Other +contexts like seccomp define their own return values. + +In order to simplify programs, attempts to read past the end of the +packet terminate the program execution with a verdict of 0 (ignore +packet). This means that the vast majority of BPF programs don't need +to do any explicit bounds checking. + +In addition to the bytes of the packet, some BPF programs have access +to extensions, which are essentially calls to kernel utility +functions. Currently, the only extensions supported by this package +are the Linux packet filter extensions. + +Examples + +This packet filter selects all ARP packets. + + bpf.Assemble([]bpf.Instruction{ + // Load "EtherType" field from the ethernet header. + bpf.LoadAbsolute{Off: 12, Size: 2}, + // Skip over the next instruction if EtherType is not ARP. + bpf.JumpIf{Cond: bpf.JumpNotEqual, Val: 0x0806, SkipTrue: 1}, + // Verdict is "send up to 4k of the packet to userspace." + bpf.RetConstant{Val: 4096}, + // Verdict is "ignore packet." + bpf.RetConstant{Val: 0}, + }) + +This packet filter captures a random 1% sample of traffic. + + bpf.Assemble([]bpf.Instruction{ + // Get a 32-bit random number from the Linux kernel. + bpf.LoadExtension{Num: bpf.ExtRand}, + // 1% dice roll? + bpf.JumpIf{Cond: bpf.JumpLessThan, Val: 2^32/100, SkipFalse: 1}, + // Capture. + bpf.RetConstant{Val: 4096}, + // Ignore. + bpf.RetConstant{Val: 0}, + }) + +*/ +package bpf // import "golang.org/x/net/bpf" diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/instructions.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/instructions.go new file mode 100644 index 000000000..3b4fd0891 --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/instructions.go @@ -0,0 +1,704 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package bpf + +import "fmt" + +// An Instruction is one instruction executed by the BPF virtual +// machine. +type Instruction interface { + // Assemble assembles the Instruction into a RawInstruction. + Assemble() (RawInstruction, error) +} + +// A RawInstruction is a raw BPF virtual machine instruction. +type RawInstruction struct { + // Operation to execute. + Op uint16 + // For conditional jump instructions, the number of instructions + // to skip if the condition is true/false. + Jt uint8 + Jf uint8 + // Constant parameter. The meaning depends on the Op. + K uint32 +} + +// Assemble implements the Instruction Assemble method. +func (ri RawInstruction) Assemble() (RawInstruction, error) { return ri, nil } + +// Disassemble parses ri into an Instruction and returns it. If ri is +// not recognized by this package, ri itself is returned. +func (ri RawInstruction) Disassemble() Instruction { + switch ri.Op & opMaskCls { + case opClsLoadA, opClsLoadX: + reg := Register(ri.Op & opMaskLoadDest) + sz := 0 + switch ri.Op & opMaskLoadWidth { + case opLoadWidth4: + sz = 4 + case opLoadWidth2: + sz = 2 + case opLoadWidth1: + sz = 1 + default: + return ri + } + switch ri.Op & opMaskLoadMode { + case opAddrModeImmediate: + if sz != 4 { + return ri + } + return LoadConstant{Dst: reg, Val: ri.K} + case opAddrModeScratch: + if sz != 4 || ri.K > 15 { + return ri + } + return LoadScratch{Dst: reg, N: int(ri.K)} + case opAddrModeAbsolute: + if ri.K > extOffset+0xffffffff { + return LoadExtension{Num: Extension(-extOffset + ri.K)} + } + return LoadAbsolute{Size: sz, Off: ri.K} + case opAddrModeIndirect: + return LoadIndirect{Size: sz, Off: ri.K} + case opAddrModePacketLen: + if sz != 4 { + return ri + } + return LoadExtension{Num: ExtLen} + case opAddrModeMemShift: + return LoadMemShift{Off: ri.K} + default: + return ri + } + + case opClsStoreA: + if ri.Op != opClsStoreA || ri.K > 15 { + return ri + } + return StoreScratch{Src: RegA, N: int(ri.K)} + + case opClsStoreX: + if ri.Op != opClsStoreX || ri.K > 15 { + return ri + } + return StoreScratch{Src: RegX, N: int(ri.K)} + + case opClsALU: + switch op := ALUOp(ri.Op & opMaskOperator); op { + case ALUOpAdd, ALUOpSub, ALUOpMul, ALUOpDiv, ALUOpOr, ALUOpAnd, ALUOpShiftLeft, ALUOpShiftRight, ALUOpMod, ALUOpXor: + if ri.Op&opMaskOperandSrc != 0 { + return ALUOpX{Op: op} + } + return ALUOpConstant{Op: op, Val: ri.K} + case aluOpNeg: + return NegateA{} + default: + return ri + } + + case opClsJump: + if ri.Op&opMaskJumpConst != opClsJump { + return ri + } + switch ri.Op & opMaskJumpCond { + case opJumpAlways: + return Jump{Skip: ri.K} + case opJumpEqual: + if ri.Jt == 0 { + return JumpIf{ + Cond: JumpNotEqual, + Val: ri.K, + SkipTrue: ri.Jf, + SkipFalse: 0, + } + } + return JumpIf{ + Cond: JumpEqual, + Val: ri.K, + SkipTrue: ri.Jt, + SkipFalse: ri.Jf, + } + case opJumpGT: + if ri.Jt == 0 { + return JumpIf{ + Cond: JumpLessOrEqual, + Val: ri.K, + SkipTrue: ri.Jf, + SkipFalse: 0, + } + } + return JumpIf{ + Cond: JumpGreaterThan, + Val: ri.K, + SkipTrue: ri.Jt, + SkipFalse: ri.Jf, + } + case opJumpGE: + if ri.Jt == 0 { + return JumpIf{ + Cond: JumpLessThan, + Val: ri.K, + SkipTrue: ri.Jf, + SkipFalse: 0, + } + } + return JumpIf{ + Cond: JumpGreaterOrEqual, + Val: ri.K, + SkipTrue: ri.Jt, + SkipFalse: ri.Jf, + } + case opJumpSet: + return JumpIf{ + Cond: JumpBitsSet, + Val: ri.K, + SkipTrue: ri.Jt, + SkipFalse: ri.Jf, + } + default: + return ri + } + + case opClsReturn: + switch ri.Op { + case opClsReturn | opRetSrcA: + return RetA{} + case opClsReturn | opRetSrcConstant: + return RetConstant{Val: ri.K} + default: + return ri + } + + case opClsMisc: + switch ri.Op { + case opClsMisc | opMiscTAX: + return TAX{} + case opClsMisc | opMiscTXA: + return TXA{} + default: + return ri + } + + default: + panic("unreachable") // switch is exhaustive on the bit pattern + } +} + +// LoadConstant loads Val into register Dst. +type LoadConstant struct { + Dst Register + Val uint32 +} + +// Assemble implements the Instruction Assemble method. +func (a LoadConstant) Assemble() (RawInstruction, error) { + return assembleLoad(a.Dst, 4, opAddrModeImmediate, a.Val) +} + +// String returns the the instruction in assembler notation. +func (a LoadConstant) String() string { + switch a.Dst { + case RegA: + return fmt.Sprintf("ld #%d", a.Val) + case RegX: + return fmt.Sprintf("ldx #%d", a.Val) + default: + return fmt.Sprintf("unknown instruction: %#v", a) + } +} + +// LoadScratch loads scratch[N] into register Dst. +type LoadScratch struct { + Dst Register + N int // 0-15 +} + +// Assemble implements the Instruction Assemble method. +func (a LoadScratch) Assemble() (RawInstruction, error) { + if a.N < 0 || a.N > 15 { + return RawInstruction{}, fmt.Errorf("invalid scratch slot %d", a.N) + } + return assembleLoad(a.Dst, 4, opAddrModeScratch, uint32(a.N)) +} + +// String returns the the instruction in assembler notation. +func (a LoadScratch) String() string { + switch a.Dst { + case RegA: + return fmt.Sprintf("ld M[%d]", a.N) + case RegX: + return fmt.Sprintf("ldx M[%d]", a.N) + default: + return fmt.Sprintf("unknown instruction: %#v", a) + } +} + +// LoadAbsolute loads packet[Off:Off+Size] as an integer value into +// register A. +type LoadAbsolute struct { + Off uint32 + Size int // 1, 2 or 4 +} + +// Assemble implements the Instruction Assemble method. +func (a LoadAbsolute) Assemble() (RawInstruction, error) { + return assembleLoad(RegA, a.Size, opAddrModeAbsolute, a.Off) +} + +// String returns the the instruction in assembler notation. +func (a LoadAbsolute) String() string { + switch a.Size { + case 1: // byte + return fmt.Sprintf("ldb [%d]", a.Off) + case 2: // half word + return fmt.Sprintf("ldh [%d]", a.Off) + case 4: // word + if a.Off > extOffset+0xffffffff { + return LoadExtension{Num: Extension(a.Off + 0x1000)}.String() + } + return fmt.Sprintf("ld [%d]", a.Off) + default: + return fmt.Sprintf("unknown instruction: %#v", a) + } +} + +// LoadIndirect loads packet[X+Off:X+Off+Size] as an integer value +// into register A. +type LoadIndirect struct { + Off uint32 + Size int // 1, 2 or 4 +} + +// Assemble implements the Instruction Assemble method. +func (a LoadIndirect) Assemble() (RawInstruction, error) { + return assembleLoad(RegA, a.Size, opAddrModeIndirect, a.Off) +} + +// String returns the the instruction in assembler notation. +func (a LoadIndirect) String() string { + switch a.Size { + case 1: // byte + return fmt.Sprintf("ldb [x + %d]", a.Off) + case 2: // half word + return fmt.Sprintf("ldh [x + %d]", a.Off) + case 4: // word + return fmt.Sprintf("ld [x + %d]", a.Off) + default: + return fmt.Sprintf("unknown instruction: %#v", a) + } +} + +// LoadMemShift multiplies the first 4 bits of the byte at packet[Off] +// by 4 and stores the result in register X. +// +// This instruction is mainly useful to load into X the length of an +// IPv4 packet header in a single instruction, rather than have to do +// the arithmetic on the header's first byte by hand. +type LoadMemShift struct { + Off uint32 +} + +// Assemble implements the Instruction Assemble method. +func (a LoadMemShift) Assemble() (RawInstruction, error) { + return assembleLoad(RegX, 1, opAddrModeMemShift, a.Off) +} + +// String returns the the instruction in assembler notation. +func (a LoadMemShift) String() string { + return fmt.Sprintf("ldx 4*([%d]&0xf)", a.Off) +} + +// LoadExtension invokes a linux-specific extension and stores the +// result in register A. +type LoadExtension struct { + Num Extension +} + +// Assemble implements the Instruction Assemble method. +func (a LoadExtension) Assemble() (RawInstruction, error) { + if a.Num == ExtLen { + return assembleLoad(RegA, 4, opAddrModePacketLen, 0) + } + return assembleLoad(RegA, 4, opAddrModeAbsolute, uint32(extOffset+a.Num)) +} + +// String returns the the instruction in assembler notation. +func (a LoadExtension) String() string { + switch a.Num { + case ExtLen: + return "ld #len" + case ExtProto: + return "ld #proto" + case ExtType: + return "ld #type" + case ExtPayloadOffset: + return "ld #poff" + case ExtInterfaceIndex: + return "ld #ifidx" + case ExtNetlinkAttr: + return "ld #nla" + case ExtNetlinkAttrNested: + return "ld #nlan" + case ExtMark: + return "ld #mark" + case ExtQueue: + return "ld #queue" + case ExtLinkLayerType: + return "ld #hatype" + case ExtRXHash: + return "ld #rxhash" + case ExtCPUID: + return "ld #cpu" + case ExtVLANTag: + return "ld #vlan_tci" + case ExtVLANTagPresent: + return "ld #vlan_avail" + case ExtVLANProto: + return "ld #vlan_tpid" + case ExtRand: + return "ld #rand" + default: + return fmt.Sprintf("unknown instruction: %#v", a) + } +} + +// StoreScratch stores register Src into scratch[N]. +type StoreScratch struct { + Src Register + N int // 0-15 +} + +// Assemble implements the Instruction Assemble method. +func (a StoreScratch) Assemble() (RawInstruction, error) { + if a.N < 0 || a.N > 15 { + return RawInstruction{}, fmt.Errorf("invalid scratch slot %d", a.N) + } + var op uint16 + switch a.Src { + case RegA: + op = opClsStoreA + case RegX: + op = opClsStoreX + default: + return RawInstruction{}, fmt.Errorf("invalid source register %v", a.Src) + } + + return RawInstruction{ + Op: op, + K: uint32(a.N), + }, nil +} + +// String returns the the instruction in assembler notation. +func (a StoreScratch) String() string { + switch a.Src { + case RegA: + return fmt.Sprintf("st M[%d]", a.N) + case RegX: + return fmt.Sprintf("stx M[%d]", a.N) + default: + return fmt.Sprintf("unknown instruction: %#v", a) + } +} + +// ALUOpConstant executes A = A <Op> Val. +type ALUOpConstant struct { + Op ALUOp + Val uint32 +} + +// Assemble implements the Instruction Assemble method. +func (a ALUOpConstant) Assemble() (RawInstruction, error) { + return RawInstruction{ + Op: opClsALU | opALUSrcConstant | uint16(a.Op), + K: a.Val, + }, nil +} + +// String returns the the instruction in assembler notation. +func (a ALUOpConstant) String() string { + switch a.Op { + case ALUOpAdd: + return fmt.Sprintf("add #%d", a.Val) + case ALUOpSub: + return fmt.Sprintf("sub #%d", a.Val) + case ALUOpMul: + return fmt.Sprintf("mul #%d", a.Val) + case ALUOpDiv: + return fmt.Sprintf("div #%d", a.Val) + case ALUOpMod: + return fmt.Sprintf("mod #%d", a.Val) + case ALUOpAnd: + return fmt.Sprintf("and #%d", a.Val) + case ALUOpOr: + return fmt.Sprintf("or #%d", a.Val) + case ALUOpXor: + return fmt.Sprintf("xor #%d", a.Val) + case ALUOpShiftLeft: + return fmt.Sprintf("lsh #%d", a.Val) + case ALUOpShiftRight: + return fmt.Sprintf("rsh #%d", a.Val) + default: + return fmt.Sprintf("unknown instruction: %#v", a) + } +} + +// ALUOpX executes A = A <Op> X +type ALUOpX struct { + Op ALUOp +} + +// Assemble implements the Instruction Assemble method. +func (a ALUOpX) Assemble() (RawInstruction, error) { + return RawInstruction{ + Op: opClsALU | opALUSrcX | uint16(a.Op), + }, nil +} + +// String returns the the instruction in assembler notation. +func (a ALUOpX) String() string { + switch a.Op { + case ALUOpAdd: + return "add x" + case ALUOpSub: + return "sub x" + case ALUOpMul: + return "mul x" + case ALUOpDiv: + return "div x" + case ALUOpMod: + return "mod x" + case ALUOpAnd: + return "and x" + case ALUOpOr: + return "or x" + case ALUOpXor: + return "xor x" + case ALUOpShiftLeft: + return "lsh x" + case ALUOpShiftRight: + return "rsh x" + default: + return fmt.Sprintf("unknown instruction: %#v", a) + } +} + +// NegateA executes A = -A. +type NegateA struct{} + +// Assemble implements the Instruction Assemble method. +func (a NegateA) Assemble() (RawInstruction, error) { + return RawInstruction{ + Op: opClsALU | uint16(aluOpNeg), + }, nil +} + +// String returns the the instruction in assembler notation. +func (a NegateA) String() string { + return fmt.Sprintf("neg") +} + +// Jump skips the following Skip instructions in the program. +type Jump struct { + Skip uint32 +} + +// Assemble implements the Instruction Assemble method. +func (a Jump) Assemble() (RawInstruction, error) { + return RawInstruction{ + Op: opClsJump | opJumpAlways, + K: a.Skip, + }, nil +} + +// String returns the the instruction in assembler notation. +func (a Jump) String() string { + return fmt.Sprintf("ja %d", a.Skip) +} + +// JumpIf skips the following Skip instructions in the program if A +// <Cond> Val is true. +type JumpIf struct { + Cond JumpTest + Val uint32 + SkipTrue uint8 + SkipFalse uint8 +} + +// Assemble implements the Instruction Assemble method. +func (a JumpIf) Assemble() (RawInstruction, error) { + var ( + cond uint16 + flip bool + ) + switch a.Cond { + case JumpEqual: + cond = opJumpEqual + case JumpNotEqual: + cond, flip = opJumpEqual, true + case JumpGreaterThan: + cond = opJumpGT + case JumpLessThan: + cond, flip = opJumpGE, true + case JumpGreaterOrEqual: + cond = opJumpGE + case JumpLessOrEqual: + cond, flip = opJumpGT, true + case JumpBitsSet: + cond = opJumpSet + case JumpBitsNotSet: + cond, flip = opJumpSet, true + default: + return RawInstruction{}, fmt.Errorf("unknown JumpTest %v", a.Cond) + } + jt, jf := a.SkipTrue, a.SkipFalse + if flip { + jt, jf = jf, jt + } + return RawInstruction{ + Op: opClsJump | cond, + Jt: jt, + Jf: jf, + K: a.Val, + }, nil +} + +// String returns the the instruction in assembler notation. +func (a JumpIf) String() string { + switch a.Cond { + // K == A + case JumpEqual: + return conditionalJump(a, "jeq", "jneq") + // K != A + case JumpNotEqual: + return fmt.Sprintf("jneq #%d,%d", a.Val, a.SkipTrue) + // K > A + case JumpGreaterThan: + return conditionalJump(a, "jgt", "jle") + // K < A + case JumpLessThan: + return fmt.Sprintf("jlt #%d,%d", a.Val, a.SkipTrue) + // K >= A + case JumpGreaterOrEqual: + return conditionalJump(a, "jge", "jlt") + // K <= A + case JumpLessOrEqual: + return fmt.Sprintf("jle #%d,%d", a.Val, a.SkipTrue) + // K & A != 0 + case JumpBitsSet: + if a.SkipFalse > 0 { + return fmt.Sprintf("jset #%d,%d,%d", a.Val, a.SkipTrue, a.SkipFalse) + } + return fmt.Sprintf("jset #%d,%d", a.Val, a.SkipTrue) + // K & A == 0, there is no assembler instruction for JumpBitNotSet, use JumpBitSet and invert skips + case JumpBitsNotSet: + return JumpIf{Cond: JumpBitsSet, SkipTrue: a.SkipFalse, SkipFalse: a.SkipTrue, Val: a.Val}.String() + default: + return fmt.Sprintf("unknown instruction: %#v", a) + } +} + +func conditionalJump(inst JumpIf, positiveJump, negativeJump string) string { + if inst.SkipTrue > 0 { + if inst.SkipFalse > 0 { + return fmt.Sprintf("%s #%d,%d,%d", positiveJump, inst.Val, inst.SkipTrue, inst.SkipFalse) + } + return fmt.Sprintf("%s #%d,%d", positiveJump, inst.Val, inst.SkipTrue) + } + return fmt.Sprintf("%s #%d,%d", negativeJump, inst.Val, inst.SkipFalse) +} + +// RetA exits the BPF program, returning the value of register A. +type RetA struct{} + +// Assemble implements the Instruction Assemble method. +func (a RetA) Assemble() (RawInstruction, error) { + return RawInstruction{ + Op: opClsReturn | opRetSrcA, + }, nil +} + +// String returns the the instruction in assembler notation. +func (a RetA) String() string { + return fmt.Sprintf("ret a") +} + +// RetConstant exits the BPF program, returning a constant value. +type RetConstant struct { + Val uint32 +} + +// Assemble implements the Instruction Assemble method. +func (a RetConstant) Assemble() (RawInstruction, error) { + return RawInstruction{ + Op: opClsReturn | opRetSrcConstant, + K: a.Val, + }, nil +} + +// String returns the the instruction in assembler notation. +func (a RetConstant) String() string { + return fmt.Sprintf("ret #%d", a.Val) +} + +// TXA copies the value of register X to register A. +type TXA struct{} + +// Assemble implements the Instruction Assemble method. +func (a TXA) Assemble() (RawInstruction, error) { + return RawInstruction{ + Op: opClsMisc | opMiscTXA, + }, nil +} + +// String returns the the instruction in assembler notation. +func (a TXA) String() string { + return fmt.Sprintf("txa") +} + +// TAX copies the value of register A to register X. +type TAX struct{} + +// Assemble implements the Instruction Assemble method. +func (a TAX) Assemble() (RawInstruction, error) { + return RawInstruction{ + Op: opClsMisc | opMiscTAX, + }, nil +} + +// String returns the the instruction in assembler notation. +func (a TAX) String() string { + return fmt.Sprintf("tax") +} + +func assembleLoad(dst Register, loadSize int, mode uint16, k uint32) (RawInstruction, error) { + var ( + cls uint16 + sz uint16 + ) + switch dst { + case RegA: + cls = opClsLoadA + case RegX: + cls = opClsLoadX + default: + return RawInstruction{}, fmt.Errorf("invalid target register %v", dst) + } + switch loadSize { + case 1: + sz = opLoadWidth1 + case 2: + sz = opLoadWidth2 + case 4: + sz = opLoadWidth4 + default: + return RawInstruction{}, fmt.Errorf("invalid load byte length %d", sz) + } + return RawInstruction{ + Op: cls | sz | mode, + K: k, + }, nil +} diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/instructions_test.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/instructions_test.go new file mode 100644 index 000000000..dde474aba --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/instructions_test.go @@ -0,0 +1,525 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package bpf + +import ( + "fmt" + "io/ioutil" + "reflect" + "strconv" + "strings" + "testing" +) + +// This is a direct translation of the program in +// testdata/all_instructions.txt. +var allInstructions = []Instruction{ + LoadConstant{Dst: RegA, Val: 42}, + LoadConstant{Dst: RegX, Val: 42}, + + LoadScratch{Dst: RegA, N: 3}, + LoadScratch{Dst: RegX, N: 3}, + + LoadAbsolute{Off: 42, Size: 1}, + LoadAbsolute{Off: 42, Size: 2}, + LoadAbsolute{Off: 42, Size: 4}, + + LoadIndirect{Off: 42, Size: 1}, + LoadIndirect{Off: 42, Size: 2}, + LoadIndirect{Off: 42, Size: 4}, + + LoadMemShift{Off: 42}, + + LoadExtension{Num: ExtLen}, + LoadExtension{Num: ExtProto}, + LoadExtension{Num: ExtType}, + LoadExtension{Num: ExtRand}, + + StoreScratch{Src: RegA, N: 3}, + StoreScratch{Src: RegX, N: 3}, + + ALUOpConstant{Op: ALUOpAdd, Val: 42}, + ALUOpConstant{Op: ALUOpSub, Val: 42}, + ALUOpConstant{Op: ALUOpMul, Val: 42}, + ALUOpConstant{Op: ALUOpDiv, Val: 42}, + ALUOpConstant{Op: ALUOpOr, Val: 42}, + ALUOpConstant{Op: ALUOpAnd, Val: 42}, + ALUOpConstant{Op: ALUOpShiftLeft, Val: 42}, + ALUOpConstant{Op: ALUOpShiftRight, Val: 42}, + ALUOpConstant{Op: ALUOpMod, Val: 42}, + ALUOpConstant{Op: ALUOpXor, Val: 42}, + + ALUOpX{Op: ALUOpAdd}, + ALUOpX{Op: ALUOpSub}, + ALUOpX{Op: ALUOpMul}, + ALUOpX{Op: ALUOpDiv}, + ALUOpX{Op: ALUOpOr}, + ALUOpX{Op: ALUOpAnd}, + ALUOpX{Op: ALUOpShiftLeft}, + ALUOpX{Op: ALUOpShiftRight}, + ALUOpX{Op: ALUOpMod}, + ALUOpX{Op: ALUOpXor}, + + NegateA{}, + + Jump{Skip: 10}, + JumpIf{Cond: JumpEqual, Val: 42, SkipTrue: 8, SkipFalse: 9}, + JumpIf{Cond: JumpNotEqual, Val: 42, SkipTrue: 8}, + JumpIf{Cond: JumpLessThan, Val: 42, SkipTrue: 7}, + JumpIf{Cond: JumpLessOrEqual, Val: 42, SkipTrue: 6}, + JumpIf{Cond: JumpGreaterThan, Val: 42, SkipTrue: 4, SkipFalse: 5}, + JumpIf{Cond: JumpGreaterOrEqual, Val: 42, SkipTrue: 3, SkipFalse: 4}, + JumpIf{Cond: JumpBitsSet, Val: 42, SkipTrue: 2, SkipFalse: 3}, + + TAX{}, + TXA{}, + + RetA{}, + RetConstant{Val: 42}, +} +var allInstructionsExpected = "testdata/all_instructions.bpf" + +// Check that we produce the same output as the canonical bpf_asm +// linux kernel tool. +func TestInterop(t *testing.T) { + out, err := Assemble(allInstructions) + if err != nil { + t.Fatalf("assembly of allInstructions program failed: %s", err) + } + t.Logf("Assembled program is %d instructions long", len(out)) + + bs, err := ioutil.ReadFile(allInstructionsExpected) + if err != nil { + t.Fatalf("reading %s: %s", allInstructionsExpected, err) + } + // First statement is the number of statements, last statement is + // empty. We just ignore both and rely on slice length. + stmts := strings.Split(string(bs), ",") + if len(stmts)-2 != len(out) { + t.Fatalf("test program lengths don't match: %s has %d, Go implementation has %d", allInstructionsExpected, len(stmts)-2, len(allInstructions)) + } + + for i, stmt := range stmts[1 : len(stmts)-2] { + nums := strings.Split(stmt, " ") + if len(nums) != 4 { + t.Fatalf("malformed instruction %d in %s: %s", i+1, allInstructionsExpected, stmt) + } + + actual := out[i] + + op, err := strconv.ParseUint(nums[0], 10, 16) + if err != nil { + t.Fatalf("malformed opcode %s in instruction %d of %s", nums[0], i+1, allInstructionsExpected) + } + if actual.Op != uint16(op) { + t.Errorf("opcode mismatch on instruction %d (%#v): got 0x%02x, want 0x%02x", i+1, allInstructions[i], actual.Op, op) + } + + jt, err := strconv.ParseUint(nums[1], 10, 8) + if err != nil { + t.Fatalf("malformed jt offset %s in instruction %d of %s", nums[1], i+1, allInstructionsExpected) + } + if actual.Jt != uint8(jt) { + t.Errorf("jt mismatch on instruction %d (%#v): got %d, want %d", i+1, allInstructions[i], actual.Jt, jt) + } + + jf, err := strconv.ParseUint(nums[2], 10, 8) + if err != nil { + t.Fatalf("malformed jf offset %s in instruction %d of %s", nums[2], i+1, allInstructionsExpected) + } + if actual.Jf != uint8(jf) { + t.Errorf("jf mismatch on instruction %d (%#v): got %d, want %d", i+1, allInstructions[i], actual.Jf, jf) + } + + k, err := strconv.ParseUint(nums[3], 10, 32) + if err != nil { + t.Fatalf("malformed constant %s in instruction %d of %s", nums[3], i+1, allInstructionsExpected) + } + if actual.K != uint32(k) { + t.Errorf("constant mismatch on instruction %d (%#v): got %d, want %d", i+1, allInstructions[i], actual.K, k) + } + } +} + +// Check that assembly and disassembly match each other. +func TestAsmDisasm(t *testing.T) { + prog1, err := Assemble(allInstructions) + if err != nil { + t.Fatalf("assembly of allInstructions program failed: %s", err) + } + t.Logf("Assembled program is %d instructions long", len(prog1)) + + got, allDecoded := Disassemble(prog1) + if !allDecoded { + t.Errorf("Disassemble(Assemble(allInstructions)) produced unrecognized instructions:") + for i, inst := range got { + if r, ok := inst.(RawInstruction); ok { + t.Logf(" insn %d, %#v --> %#v", i+1, allInstructions[i], r) + } + } + } + + if len(allInstructions) != len(got) { + t.Fatalf("disassembly changed program size: %d insns before, %d insns after", len(allInstructions), len(got)) + } + if !reflect.DeepEqual(allInstructions, got) { + t.Errorf("program mutated by disassembly:") + for i := range got { + if !reflect.DeepEqual(allInstructions[i], got[i]) { + t.Logf(" insn %d, s: %#v, p1: %#v, got: %#v", i+1, allInstructions[i], prog1[i], got[i]) + } + } + } +} + +type InvalidInstruction struct{} + +func (a InvalidInstruction) Assemble() (RawInstruction, error) { + return RawInstruction{}, fmt.Errorf("Invalid Instruction") +} + +func (a InvalidInstruction) String() string { + return fmt.Sprintf("unknown instruction: %#v", a) +} + +func TestString(t *testing.T) { + testCases := []struct { + instruction Instruction + assembler string + }{ + { + instruction: LoadConstant{Dst: RegA, Val: 42}, + assembler: "ld #42", + }, + { + instruction: LoadConstant{Dst: RegX, Val: 42}, + assembler: "ldx #42", + }, + { + instruction: LoadConstant{Dst: 0xffff, Val: 42}, + assembler: "unknown instruction: bpf.LoadConstant{Dst:0xffff, Val:0x2a}", + }, + { + instruction: LoadScratch{Dst: RegA, N: 3}, + assembler: "ld M[3]", + }, + { + instruction: LoadScratch{Dst: RegX, N: 3}, + assembler: "ldx M[3]", + }, + { + instruction: LoadScratch{Dst: 0xffff, N: 3}, + assembler: "unknown instruction: bpf.LoadScratch{Dst:0xffff, N:3}", + }, + { + instruction: LoadAbsolute{Off: 42, Size: 1}, + assembler: "ldb [42]", + }, + { + instruction: LoadAbsolute{Off: 42, Size: 2}, + assembler: "ldh [42]", + }, + { + instruction: LoadAbsolute{Off: 42, Size: 4}, + assembler: "ld [42]", + }, + { + instruction: LoadAbsolute{Off: 42, Size: -1}, + assembler: "unknown instruction: bpf.LoadAbsolute{Off:0x2a, Size:-1}", + }, + { + instruction: LoadIndirect{Off: 42, Size: 1}, + assembler: "ldb [x + 42]", + }, + { + instruction: LoadIndirect{Off: 42, Size: 2}, + assembler: "ldh [x + 42]", + }, + { + instruction: LoadIndirect{Off: 42, Size: 4}, + assembler: "ld [x + 42]", + }, + { + instruction: LoadIndirect{Off: 42, Size: -1}, + assembler: "unknown instruction: bpf.LoadIndirect{Off:0x2a, Size:-1}", + }, + { + instruction: LoadMemShift{Off: 42}, + assembler: "ldx 4*([42]&0xf)", + }, + { + instruction: LoadExtension{Num: ExtLen}, + assembler: "ld #len", + }, + { + instruction: LoadExtension{Num: ExtProto}, + assembler: "ld #proto", + }, + { + instruction: LoadExtension{Num: ExtType}, + assembler: "ld #type", + }, + { + instruction: LoadExtension{Num: ExtPayloadOffset}, + assembler: "ld #poff", + }, + { + instruction: LoadExtension{Num: ExtInterfaceIndex}, + assembler: "ld #ifidx", + }, + { + instruction: LoadExtension{Num: ExtNetlinkAttr}, + assembler: "ld #nla", + }, + { + instruction: LoadExtension{Num: ExtNetlinkAttrNested}, + assembler: "ld #nlan", + }, + { + instruction: LoadExtension{Num: ExtMark}, + assembler: "ld #mark", + }, + { + instruction: LoadExtension{Num: ExtQueue}, + assembler: "ld #queue", + }, + { + instruction: LoadExtension{Num: ExtLinkLayerType}, + assembler: "ld #hatype", + }, + { + instruction: LoadExtension{Num: ExtRXHash}, + assembler: "ld #rxhash", + }, + { + instruction: LoadExtension{Num: ExtCPUID}, + assembler: "ld #cpu", + }, + { + instruction: LoadExtension{Num: ExtVLANTag}, + assembler: "ld #vlan_tci", + }, + { + instruction: LoadExtension{Num: ExtVLANTagPresent}, + assembler: "ld #vlan_avail", + }, + { + instruction: LoadExtension{Num: ExtVLANProto}, + assembler: "ld #vlan_tpid", + }, + { + instruction: LoadExtension{Num: ExtRand}, + assembler: "ld #rand", + }, + { + instruction: LoadAbsolute{Off: 0xfffff038, Size: 4}, + assembler: "ld #rand", + }, + { + instruction: LoadExtension{Num: 0xfff}, + assembler: "unknown instruction: bpf.LoadExtension{Num:4095}", + }, + { + instruction: StoreScratch{Src: RegA, N: 3}, + assembler: "st M[3]", + }, + { + instruction: StoreScratch{Src: RegX, N: 3}, + assembler: "stx M[3]", + }, + { + instruction: StoreScratch{Src: 0xffff, N: 3}, + assembler: "unknown instruction: bpf.StoreScratch{Src:0xffff, N:3}", + }, + { + instruction: ALUOpConstant{Op: ALUOpAdd, Val: 42}, + assembler: "add #42", + }, + { + instruction: ALUOpConstant{Op: ALUOpSub, Val: 42}, + assembler: "sub #42", + }, + { + instruction: ALUOpConstant{Op: ALUOpMul, Val: 42}, + assembler: "mul #42", + }, + { + instruction: ALUOpConstant{Op: ALUOpDiv, Val: 42}, + assembler: "div #42", + }, + { + instruction: ALUOpConstant{Op: ALUOpOr, Val: 42}, + assembler: "or #42", + }, + { + instruction: ALUOpConstant{Op: ALUOpAnd, Val: 42}, + assembler: "and #42", + }, + { + instruction: ALUOpConstant{Op: ALUOpShiftLeft, Val: 42}, + assembler: "lsh #42", + }, + { + instruction: ALUOpConstant{Op: ALUOpShiftRight, Val: 42}, + assembler: "rsh #42", + }, + { + instruction: ALUOpConstant{Op: ALUOpMod, Val: 42}, + assembler: "mod #42", + }, + { + instruction: ALUOpConstant{Op: ALUOpXor, Val: 42}, + assembler: "xor #42", + }, + { + instruction: ALUOpConstant{Op: 0xffff, Val: 42}, + assembler: "unknown instruction: bpf.ALUOpConstant{Op:0xffff, Val:0x2a}", + }, + { + instruction: ALUOpX{Op: ALUOpAdd}, + assembler: "add x", + }, + { + instruction: ALUOpX{Op: ALUOpSub}, + assembler: "sub x", + }, + { + instruction: ALUOpX{Op: ALUOpMul}, + assembler: "mul x", + }, + { + instruction: ALUOpX{Op: ALUOpDiv}, + assembler: "div x", + }, + { + instruction: ALUOpX{Op: ALUOpOr}, + assembler: "or x", + }, + { + instruction: ALUOpX{Op: ALUOpAnd}, + assembler: "and x", + }, + { + instruction: ALUOpX{Op: ALUOpShiftLeft}, + assembler: "lsh x", + }, + { + instruction: ALUOpX{Op: ALUOpShiftRight}, + assembler: "rsh x", + }, + { + instruction: ALUOpX{Op: ALUOpMod}, + assembler: "mod x", + }, + { + instruction: ALUOpX{Op: ALUOpXor}, + assembler: "xor x", + }, + { + instruction: ALUOpX{Op: 0xffff}, + assembler: "unknown instruction: bpf.ALUOpX{Op:0xffff}", + }, + { + instruction: NegateA{}, + assembler: "neg", + }, + { + instruction: Jump{Skip: 10}, + assembler: "ja 10", + }, + { + instruction: JumpIf{Cond: JumpEqual, Val: 42, SkipTrue: 8, SkipFalse: 9}, + assembler: "jeq #42,8,9", + }, + { + instruction: JumpIf{Cond: JumpEqual, Val: 42, SkipTrue: 8}, + assembler: "jeq #42,8", + }, + { + instruction: JumpIf{Cond: JumpEqual, Val: 42, SkipFalse: 8}, + assembler: "jneq #42,8", + }, + { + instruction: JumpIf{Cond: JumpNotEqual, Val: 42, SkipTrue: 8}, + assembler: "jneq #42,8", + }, + { + instruction: JumpIf{Cond: JumpLessThan, Val: 42, SkipTrue: 7}, + assembler: "jlt #42,7", + }, + { + instruction: JumpIf{Cond: JumpLessOrEqual, Val: 42, SkipTrue: 6}, + assembler: "jle #42,6", + }, + { + instruction: JumpIf{Cond: JumpGreaterThan, Val: 42, SkipTrue: 4, SkipFalse: 5}, + assembler: "jgt #42,4,5", + }, + { + instruction: JumpIf{Cond: JumpGreaterThan, Val: 42, SkipTrue: 4}, + assembler: "jgt #42,4", + }, + { + instruction: JumpIf{Cond: JumpGreaterOrEqual, Val: 42, SkipTrue: 3, SkipFalse: 4}, + assembler: "jge #42,3,4", + }, + { + instruction: JumpIf{Cond: JumpGreaterOrEqual, Val: 42, SkipTrue: 3}, + assembler: "jge #42,3", + }, + { + instruction: JumpIf{Cond: JumpBitsSet, Val: 42, SkipTrue: 2, SkipFalse: 3}, + assembler: "jset #42,2,3", + }, + { + instruction: JumpIf{Cond: JumpBitsSet, Val: 42, SkipTrue: 2}, + assembler: "jset #42,2", + }, + { + instruction: JumpIf{Cond: JumpBitsNotSet, Val: 42, SkipTrue: 2, SkipFalse: 3}, + assembler: "jset #42,3,2", + }, + { + instruction: JumpIf{Cond: JumpBitsNotSet, Val: 42, SkipTrue: 2}, + assembler: "jset #42,0,2", + }, + { + instruction: JumpIf{Cond: 0xffff, Val: 42, SkipTrue: 1, SkipFalse: 2}, + assembler: "unknown instruction: bpf.JumpIf{Cond:0xffff, Val:0x2a, SkipTrue:0x1, SkipFalse:0x2}", + }, + { + instruction: TAX{}, + assembler: "tax", + }, + { + instruction: TXA{}, + assembler: "txa", + }, + { + instruction: RetA{}, + assembler: "ret a", + }, + { + instruction: RetConstant{Val: 42}, + assembler: "ret #42", + }, + // Invalid instruction + { + instruction: InvalidInstruction{}, + assembler: "unknown instruction: bpf.InvalidInstruction{}", + }, + } + + for _, testCase := range testCases { + if input, ok := testCase.instruction.(fmt.Stringer); ok { + got := input.String() + if got != testCase.assembler { + t.Errorf("String did not return expected assembler notation, expected: %s, got: %s", testCase.assembler, got) + } + } else { + t.Errorf("Instruction %#v is not a fmt.Stringer", testCase.instruction) + } + } +} diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/setter.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/setter.go new file mode 100644 index 000000000..43e35f0ac --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/setter.go @@ -0,0 +1,10 @@ +// Copyright 2017 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package bpf + +// A Setter is a type which can attach a compiled BPF filter to itself. +type Setter interface { + SetBPF(filter []RawInstruction) error +} diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/testdata/all_instructions.bpf b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/testdata/all_instructions.bpf new file mode 100644 index 000000000..f87144064 --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/testdata/all_instructions.bpf @@ -0,0 +1 @@ +50,0 0 0 42,1 0 0 42,96 0 0 3,97 0 0 3,48 0 0 42,40 0 0 42,32 0 0 42,80 0 0 42,72 0 0 42,64 0 0 42,177 0 0 42,128 0 0 0,32 0 0 4294963200,32 0 0 4294963204,32 0 0 4294963256,2 0 0 3,3 0 0 3,4 0 0 42,20 0 0 42,36 0 0 42,52 0 0 42,68 0 0 42,84 0 0 42,100 0 0 42,116 0 0 42,148 0 0 42,164 0 0 42,12 0 0 0,28 0 0 0,44 0 0 0,60 0 0 0,76 0 0 0,92 0 0 0,108 0 0 0,124 0 0 0,156 0 0 0,172 0 0 0,132 0 0 0,5 0 0 10,21 8 9 42,21 0 8 42,53 0 7 42,37 0 6 42,37 4 5 42,53 3 4 42,69 2 3 42,7 0 0 0,135 0 0 0,22 0 0 0,6 0 0 0, diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/testdata/all_instructions.txt b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/testdata/all_instructions.txt new file mode 100644 index 000000000..304550155 --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/testdata/all_instructions.txt @@ -0,0 +1,79 @@ +# This filter is compiled to all_instructions.bpf by the `bpf_asm` +# tool, which can be found in the linux kernel source tree under +# tools/net. + +# Load immediate +ld #42 +ldx #42 + +# Load scratch +ld M[3] +ldx M[3] + +# Load absolute +ldb [42] +ldh [42] +ld [42] + +# Load indirect +ldb [x + 42] +ldh [x + 42] +ld [x + 42] + +# Load IPv4 header length +ldx 4*([42]&0xf) + +# Run extension function +ld #len +ld #proto +ld #type +ld #rand + +# Store scratch +st M[3] +stx M[3] + +# A <op> constant +add #42 +sub #42 +mul #42 +div #42 +or #42 +and #42 +lsh #42 +rsh #42 +mod #42 +xor #42 + +# A <op> X +add x +sub x +mul x +div x +or x +and x +lsh x +rsh x +mod x +xor x + +# !A +neg + +# Jumps +ja end +jeq #42,prev,end +jne #42,end +jlt #42,end +jle #42,end +jgt #42,prev,end +jge #42,prev,end +jset #42,prev,end + +# Register transfers +tax +txa + +# Returns +prev: ret a +end: ret #42 diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm.go new file mode 100644 index 000000000..4c656f1e1 --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm.go @@ -0,0 +1,140 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package bpf + +import ( + "errors" + "fmt" +) + +// A VM is an emulated BPF virtual machine. +type VM struct { + filter []Instruction +} + +// NewVM returns a new VM using the input BPF program. +func NewVM(filter []Instruction) (*VM, error) { + if len(filter) == 0 { + return nil, errors.New("one or more Instructions must be specified") + } + + for i, ins := range filter { + check := len(filter) - (i + 1) + switch ins := ins.(type) { + // Check for out-of-bounds jumps in instructions + case Jump: + if check <= int(ins.Skip) { + return nil, fmt.Errorf("cannot jump %d instructions; jumping past program bounds", ins.Skip) + } + case JumpIf: + if check <= int(ins.SkipTrue) { + return nil, fmt.Errorf("cannot jump %d instructions in true case; jumping past program bounds", ins.SkipTrue) + } + if check <= int(ins.SkipFalse) { + return nil, fmt.Errorf("cannot jump %d instructions in false case; jumping past program bounds", ins.SkipFalse) + } + // Check for division or modulus by zero + case ALUOpConstant: + if ins.Val != 0 { + break + } + + switch ins.Op { + case ALUOpDiv, ALUOpMod: + return nil, errors.New("cannot divide by zero using ALUOpConstant") + } + // Check for unknown extensions + case LoadExtension: + switch ins.Num { + case ExtLen: + default: + return nil, fmt.Errorf("extension %d not implemented", ins.Num) + } + } + } + + // Make sure last instruction is a return instruction + switch filter[len(filter)-1].(type) { + case RetA, RetConstant: + default: + return nil, errors.New("BPF program must end with RetA or RetConstant") + } + + // Though our VM works using disassembled instructions, we + // attempt to assemble the input filter anyway to ensure it is compatible + // with an operating system VM. + _, err := Assemble(filter) + + return &VM{ + filter: filter, + }, err +} + +// Run runs the VM's BPF program against the input bytes. +// Run returns the number of bytes accepted by the BPF program, and any errors +// which occurred while processing the program. +func (v *VM) Run(in []byte) (int, error) { + var ( + // Registers of the virtual machine + regA uint32 + regX uint32 + regScratch [16]uint32 + + // OK is true if the program should continue processing the next + // instruction, or false if not, causing the loop to break + ok = true + ) + + // TODO(mdlayher): implement: + // - NegateA: + // - would require a change from uint32 registers to int32 + // registers + + // TODO(mdlayher): add interop tests that check signedness of ALU + // operations against kernel implementation, and make sure Go + // implementation matches behavior + + for i := 0; i < len(v.filter) && ok; i++ { + ins := v.filter[i] + + switch ins := ins.(type) { + case ALUOpConstant: + regA = aluOpConstant(ins, regA) + case ALUOpX: + regA, ok = aluOpX(ins, regA, regX) + case Jump: + i += int(ins.Skip) + case JumpIf: + jump := jumpIf(ins, regA) + i += jump + case LoadAbsolute: + regA, ok = loadAbsolute(ins, in) + case LoadConstant: + regA, regX = loadConstant(ins, regA, regX) + case LoadExtension: + regA = loadExtension(ins, in) + case LoadIndirect: + regA, ok = loadIndirect(ins, in, regX) + case LoadMemShift: + regX, ok = loadMemShift(ins, in) + case LoadScratch: + regA, regX = loadScratch(ins, regScratch, regA, regX) + case RetA: + return int(regA), nil + case RetConstant: + return int(ins.Val), nil + case StoreScratch: + regScratch = storeScratch(ins, regScratch, regA, regX) + case TAX: + regX = regA + case TXA: + regA = regX + default: + return 0, fmt.Errorf("unknown Instruction at index %d: %T", i, ins) + } + } + + return 0, nil +} diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_aluop_test.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_aluop_test.go new file mode 100644 index 000000000..16678244a --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_aluop_test.go @@ -0,0 +1,512 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package bpf_test + +import ( + "testing" + + "golang.org/x/net/bpf" +) + +func TestVMALUOpAdd(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + bpf.ALUOpConstant{ + Op: bpf.ALUOpAdd, + Val: 3, + }, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 8, 2, 3, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 3, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMALUOpSub(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + bpf.TAX{}, + bpf.ALUOpX{ + Op: bpf.ALUOpSub, + }, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 1, 2, 3, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 0, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMALUOpMul(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + bpf.ALUOpConstant{ + Op: bpf.ALUOpMul, + Val: 2, + }, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 6, 2, 3, 4, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 4, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMALUOpDiv(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + bpf.ALUOpConstant{ + Op: bpf.ALUOpDiv, + Val: 2, + }, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 20, 2, 3, 4, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 2, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMALUOpDivByZeroALUOpConstant(t *testing.T) { + _, _, err := testVM(t, []bpf.Instruction{ + bpf.ALUOpConstant{ + Op: bpf.ALUOpDiv, + Val: 0, + }, + bpf.RetA{}, + }) + if errStr(err) != "cannot divide by zero using ALUOpConstant" { + t.Fatalf("unexpected error: %v", err) + } +} + +func TestVMALUOpDivByZeroALUOpX(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + // Load byte 0 into X + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + bpf.TAX{}, + // Load byte 1 into A + bpf.LoadAbsolute{ + Off: 9, + Size: 1, + }, + // Attempt to perform 1/0 + bpf.ALUOpX{ + Op: bpf.ALUOpDiv, + }, + // Return 4 bytes if program does not terminate + bpf.LoadConstant{ + Val: 12, + }, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0, 1, 3, 4, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 0, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMALUOpOr(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 2, + }, + bpf.ALUOpConstant{ + Op: bpf.ALUOpOr, + Val: 0x01, + }, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0x00, 0x10, 0x03, 0x04, + 0x05, 0x06, 0x07, 0x08, + 0x09, 0xff, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 9, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMALUOpAnd(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 2, + }, + bpf.ALUOpConstant{ + Op: bpf.ALUOpAnd, + Val: 0x0019, + }, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0xaa, 0x09, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 1, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMALUOpShiftLeft(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + bpf.ALUOpConstant{ + Op: bpf.ALUOpShiftLeft, + Val: 0x01, + }, + bpf.JumpIf{ + Cond: bpf.JumpEqual, + Val: 0x02, + SkipTrue: 1, + }, + bpf.RetConstant{ + Val: 0, + }, + bpf.RetConstant{ + Val: 9, + }, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0x01, 0xaa, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 1, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMALUOpShiftRight(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + bpf.ALUOpConstant{ + Op: bpf.ALUOpShiftRight, + Val: 0x01, + }, + bpf.JumpIf{ + Cond: bpf.JumpEqual, + Val: 0x04, + SkipTrue: 1, + }, + bpf.RetConstant{ + Val: 0, + }, + bpf.RetConstant{ + Val: 9, + }, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0x08, 0xff, 0xff, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 1, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMALUOpMod(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + bpf.ALUOpConstant{ + Op: bpf.ALUOpMod, + Val: 20, + }, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 30, 0, 0, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 2, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMALUOpModByZeroALUOpConstant(t *testing.T) { + _, _, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + bpf.ALUOpConstant{ + Op: bpf.ALUOpMod, + Val: 0, + }, + bpf.RetA{}, + }) + if errStr(err) != "cannot divide by zero using ALUOpConstant" { + t.Fatalf("unexpected error: %v", err) + } +} + +func TestVMALUOpModByZeroALUOpX(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + // Load byte 0 into X + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + bpf.TAX{}, + // Load byte 1 into A + bpf.LoadAbsolute{ + Off: 9, + Size: 1, + }, + // Attempt to perform 1%0 + bpf.ALUOpX{ + Op: bpf.ALUOpMod, + }, + // Return 4 bytes if program does not terminate + bpf.LoadConstant{ + Val: 12, + }, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0, 1, 3, 4, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 0, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMALUOpXor(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + bpf.ALUOpConstant{ + Op: bpf.ALUOpXor, + Val: 0x0a, + }, + bpf.JumpIf{ + Cond: bpf.JumpEqual, + Val: 0x01, + SkipTrue: 1, + }, + bpf.RetConstant{ + Val: 0, + }, + bpf.RetConstant{ + Val: 9, + }, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0x0b, 0x00, 0x00, 0x00, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 1, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMALUOpUnknown(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + bpf.ALUOpConstant{ + Op: bpf.ALUOpAdd, + Val: 1, + }, + // Verify that an unknown operation is a no-op + bpf.ALUOpConstant{ + Op: 100, + }, + bpf.JumpIf{ + Cond: bpf.JumpEqual, + Val: 0x02, + SkipTrue: 1, + }, + bpf.RetConstant{ + Val: 0, + }, + bpf.RetConstant{ + Val: 9, + }, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 1, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 1, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_bpf_test.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_bpf_test.go new file mode 100644 index 000000000..77fa8fe4a --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_bpf_test.go @@ -0,0 +1,192 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package bpf_test + +import ( + "net" + "runtime" + "testing" + "time" + + "golang.org/x/net/bpf" + "golang.org/x/net/ipv4" +) + +// A virtualMachine is a BPF virtual machine which can process an +// input packet against a BPF program and render a verdict. +type virtualMachine interface { + Run(in []byte) (int, error) +} + +// canUseOSVM indicates if the OS BPF VM is available on this platform. +func canUseOSVM() bool { + // OS BPF VM can only be used on platforms where x/net/ipv4 supports + // attaching a BPF program to a socket. + switch runtime.GOOS { + case "linux": + return true + } + + return false +} + +// All BPF tests against both the Go VM and OS VM are assumed to +// be used with a UDP socket. As a result, the entire contents +// of a UDP datagram is sent through the BPF program, but only +// the body after the UDP header will ever be returned in output. + +// testVM sets up a Go BPF VM, and if available, a native OS BPF VM +// for integration testing. +func testVM(t *testing.T, filter []bpf.Instruction) (virtualMachine, func(), error) { + goVM, err := bpf.NewVM(filter) + if err != nil { + // Some tests expect an error, so this error must be returned + // instead of fatally exiting the test + return nil, nil, err + } + + mvm := &multiVirtualMachine{ + goVM: goVM, + + t: t, + } + + // If available, add the OS VM for tests which verify that both the Go + // VM and OS VM have exactly the same output for the same input program + // and packet. + done := func() {} + if canUseOSVM() { + osVM, osVMDone := testOSVM(t, filter) + done = func() { osVMDone() } + mvm.osVM = osVM + } + + return mvm, done, nil +} + +// udpHeaderLen is the length of a UDP header. +const udpHeaderLen = 8 + +// A multiVirtualMachine is a virtualMachine which can call out to both the Go VM +// and the native OS VM, if the OS VM is available. +type multiVirtualMachine struct { + goVM virtualMachine + osVM virtualMachine + + t *testing.T +} + +func (mvm *multiVirtualMachine) Run(in []byte) (int, error) { + if len(in) < udpHeaderLen { + mvm.t.Fatalf("input must be at least length of UDP header (%d), got: %d", + udpHeaderLen, len(in)) + } + + // All tests have a UDP header as part of input, because the OS VM + // packets always will. For the Go VM, this output is trimmed before + // being sent back to tests. + goOut, goErr := mvm.goVM.Run(in) + if goOut >= udpHeaderLen { + goOut -= udpHeaderLen + } + + // If Go output is larger than the size of the packet, packet filtering + // interop tests must trim the output bytes to the length of the packet. + // The BPF VM should not do this on its own, as other uses of it do + // not trim the output byte count. + trim := len(in) - udpHeaderLen + if goOut > trim { + goOut = trim + } + + // When the OS VM is not available, process using the Go VM alone + if mvm.osVM == nil { + return goOut, goErr + } + + // The OS VM will apply its own UDP header, so remove the pseudo header + // that the Go VM needs. + osOut, err := mvm.osVM.Run(in[udpHeaderLen:]) + if err != nil { + mvm.t.Fatalf("error while running OS VM: %v", err) + } + + // Verify both VMs return same number of bytes + var mismatch bool + if goOut != osOut { + mismatch = true + mvm.t.Logf("output byte count does not match:\n- go: %v\n- os: %v", goOut, osOut) + } + + if mismatch { + mvm.t.Fatal("Go BPF and OS BPF packet outputs do not match") + } + + return goOut, goErr +} + +// An osVirtualMachine is a virtualMachine which uses the OS's BPF VM for +// processing BPF programs. +type osVirtualMachine struct { + l net.PacketConn + s net.Conn +} + +// testOSVM creates a virtualMachine which uses the OS's BPF VM by injecting +// packets into a UDP listener with a BPF program attached to it. +func testOSVM(t *testing.T, filter []bpf.Instruction) (virtualMachine, func()) { + l, err := net.ListenPacket("udp4", "127.0.0.1:0") + if err != nil { + t.Fatalf("failed to open OS VM UDP listener: %v", err) + } + + prog, err := bpf.Assemble(filter) + if err != nil { + t.Fatalf("failed to compile BPF program: %v", err) + } + + p := ipv4.NewPacketConn(l) + if err = p.SetBPF(prog); err != nil { + t.Fatalf("failed to attach BPF program to listener: %v", err) + } + + s, err := net.Dial("udp4", l.LocalAddr().String()) + if err != nil { + t.Fatalf("failed to dial connection to listener: %v", err) + } + + done := func() { + _ = s.Close() + _ = l.Close() + } + + return &osVirtualMachine{ + l: l, + s: s, + }, done +} + +// Run sends the input bytes into the OS's BPF VM and returns its verdict. +func (vm *osVirtualMachine) Run(in []byte) (int, error) { + go func() { + _, _ = vm.s.Write(in) + }() + + vm.l.SetDeadline(time.Now().Add(50 * time.Millisecond)) + + var b [512]byte + n, _, err := vm.l.ReadFrom(b[:]) + if err != nil { + // A timeout indicates that BPF filtered out the packet, and thus, + // no input should be returned. + if nerr, ok := err.(net.Error); ok && nerr.Timeout() { + return n, nil + } + + return n, err + } + + return n, nil +} diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_extension_test.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_extension_test.go new file mode 100644 index 000000000..7a48c82f3 --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_extension_test.go @@ -0,0 +1,49 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package bpf_test + +import ( + "testing" + + "golang.org/x/net/bpf" +) + +func TestVMLoadExtensionNotImplemented(t *testing.T) { + _, _, err := testVM(t, []bpf.Instruction{ + bpf.LoadExtension{ + Num: 100, + }, + bpf.RetA{}, + }) + if errStr(err) != "extension 100 not implemented" { + t.Fatalf("unexpected error: %v", err) + } +} + +func TestVMLoadExtensionExtLen(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadExtension{ + Num: bpf.ExtLen, + }, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0, 1, 2, 3, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 4, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_instructions.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_instructions.go new file mode 100644 index 000000000..516f9462b --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_instructions.go @@ -0,0 +1,174 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package bpf + +import ( + "encoding/binary" + "fmt" +) + +func aluOpConstant(ins ALUOpConstant, regA uint32) uint32 { + return aluOpCommon(ins.Op, regA, ins.Val) +} + +func aluOpX(ins ALUOpX, regA uint32, regX uint32) (uint32, bool) { + // Guard against division or modulus by zero by terminating + // the program, as the OS BPF VM does + if regX == 0 { + switch ins.Op { + case ALUOpDiv, ALUOpMod: + return 0, false + } + } + + return aluOpCommon(ins.Op, regA, regX), true +} + +func aluOpCommon(op ALUOp, regA uint32, value uint32) uint32 { + switch op { + case ALUOpAdd: + return regA + value + case ALUOpSub: + return regA - value + case ALUOpMul: + return regA * value + case ALUOpDiv: + // Division by zero not permitted by NewVM and aluOpX checks + return regA / value + case ALUOpOr: + return regA | value + case ALUOpAnd: + return regA & value + case ALUOpShiftLeft: + return regA << value + case ALUOpShiftRight: + return regA >> value + case ALUOpMod: + // Modulus by zero not permitted by NewVM and aluOpX checks + return regA % value + case ALUOpXor: + return regA ^ value + default: + return regA + } +} + +func jumpIf(ins JumpIf, value uint32) int { + var ok bool + inV := uint32(ins.Val) + + switch ins.Cond { + case JumpEqual: + ok = value == inV + case JumpNotEqual: + ok = value != inV + case JumpGreaterThan: + ok = value > inV + case JumpLessThan: + ok = value < inV + case JumpGreaterOrEqual: + ok = value >= inV + case JumpLessOrEqual: + ok = value <= inV + case JumpBitsSet: + ok = (value & inV) != 0 + case JumpBitsNotSet: + ok = (value & inV) == 0 + } + + if ok { + return int(ins.SkipTrue) + } + + return int(ins.SkipFalse) +} + +func loadAbsolute(ins LoadAbsolute, in []byte) (uint32, bool) { + offset := int(ins.Off) + size := int(ins.Size) + + return loadCommon(in, offset, size) +} + +func loadConstant(ins LoadConstant, regA uint32, regX uint32) (uint32, uint32) { + switch ins.Dst { + case RegA: + regA = ins.Val + case RegX: + regX = ins.Val + } + + return regA, regX +} + +func loadExtension(ins LoadExtension, in []byte) uint32 { + switch ins.Num { + case ExtLen: + return uint32(len(in)) + default: + panic(fmt.Sprintf("unimplemented extension: %d", ins.Num)) + } +} + +func loadIndirect(ins LoadIndirect, in []byte, regX uint32) (uint32, bool) { + offset := int(ins.Off) + int(regX) + size := int(ins.Size) + + return loadCommon(in, offset, size) +} + +func loadMemShift(ins LoadMemShift, in []byte) (uint32, bool) { + offset := int(ins.Off) + + if !inBounds(len(in), offset, 0) { + return 0, false + } + + // Mask off high 4 bits and multiply low 4 bits by 4 + return uint32(in[offset]&0x0f) * 4, true +} + +func inBounds(inLen int, offset int, size int) bool { + return offset+size <= inLen +} + +func loadCommon(in []byte, offset int, size int) (uint32, bool) { + if !inBounds(len(in), offset, size) { + return 0, false + } + + switch size { + case 1: + return uint32(in[offset]), true + case 2: + return uint32(binary.BigEndian.Uint16(in[offset : offset+size])), true + case 4: + return uint32(binary.BigEndian.Uint32(in[offset : offset+size])), true + default: + panic(fmt.Sprintf("invalid load size: %d", size)) + } +} + +func loadScratch(ins LoadScratch, regScratch [16]uint32, regA uint32, regX uint32) (uint32, uint32) { + switch ins.Dst { + case RegA: + regA = regScratch[ins.N] + case RegX: + regX = regScratch[ins.N] + } + + return regA, regX +} + +func storeScratch(ins StoreScratch, regScratch [16]uint32, regA uint32, regX uint32) [16]uint32 { + switch ins.Src { + case RegA: + regScratch[ins.N] = regA + case RegX: + regScratch[ins.N] = regX + } + + return regScratch +} diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_jump_test.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_jump_test.go new file mode 100644 index 000000000..e0a3a988b --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_jump_test.go @@ -0,0 +1,380 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package bpf_test + +import ( + "testing" + + "golang.org/x/net/bpf" +) + +func TestVMJumpOne(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + bpf.Jump{ + Skip: 1, + }, + bpf.RetConstant{ + Val: 0, + }, + bpf.RetConstant{ + Val: 9, + }, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 1, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 1, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMJumpOutOfProgram(t *testing.T) { + _, _, err := testVM(t, []bpf.Instruction{ + bpf.Jump{ + Skip: 1, + }, + bpf.RetA{}, + }) + if errStr(err) != "cannot jump 1 instructions; jumping past program bounds" { + t.Fatalf("unexpected error: %v", err) + } +} + +func TestVMJumpIfTrueOutOfProgram(t *testing.T) { + _, _, err := testVM(t, []bpf.Instruction{ + bpf.JumpIf{ + Cond: bpf.JumpEqual, + SkipTrue: 2, + }, + bpf.RetA{}, + }) + if errStr(err) != "cannot jump 2 instructions in true case; jumping past program bounds" { + t.Fatalf("unexpected error: %v", err) + } +} + +func TestVMJumpIfFalseOutOfProgram(t *testing.T) { + _, _, err := testVM(t, []bpf.Instruction{ + bpf.JumpIf{ + Cond: bpf.JumpEqual, + SkipFalse: 3, + }, + bpf.RetA{}, + }) + if errStr(err) != "cannot jump 3 instructions in false case; jumping past program bounds" { + t.Fatalf("unexpected error: %v", err) + } +} + +func TestVMJumpIfEqual(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + bpf.JumpIf{ + Cond: bpf.JumpEqual, + Val: 1, + SkipTrue: 1, + }, + bpf.RetConstant{ + Val: 0, + }, + bpf.RetConstant{ + Val: 9, + }, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 1, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 1, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMJumpIfNotEqual(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + bpf.JumpIf{ + Cond: bpf.JumpNotEqual, + Val: 1, + SkipFalse: 1, + }, + bpf.RetConstant{ + Val: 0, + }, + bpf.RetConstant{ + Val: 9, + }, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 1, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 1, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMJumpIfGreaterThan(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 4, + }, + bpf.JumpIf{ + Cond: bpf.JumpGreaterThan, + Val: 0x00010202, + SkipTrue: 1, + }, + bpf.RetConstant{ + Val: 0, + }, + bpf.RetConstant{ + Val: 12, + }, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0, 1, 2, 3, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 4, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMJumpIfLessThan(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 4, + }, + bpf.JumpIf{ + Cond: bpf.JumpLessThan, + Val: 0xff010203, + SkipTrue: 1, + }, + bpf.RetConstant{ + Val: 0, + }, + bpf.RetConstant{ + Val: 12, + }, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0, 1, 2, 3, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 4, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMJumpIfGreaterOrEqual(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 4, + }, + bpf.JumpIf{ + Cond: bpf.JumpGreaterOrEqual, + Val: 0x00010203, + SkipTrue: 1, + }, + bpf.RetConstant{ + Val: 0, + }, + bpf.RetConstant{ + Val: 12, + }, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0, 1, 2, 3, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 4, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMJumpIfLessOrEqual(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 4, + }, + bpf.JumpIf{ + Cond: bpf.JumpLessOrEqual, + Val: 0xff010203, + SkipTrue: 1, + }, + bpf.RetConstant{ + Val: 0, + }, + bpf.RetConstant{ + Val: 12, + }, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0, 1, 2, 3, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 4, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMJumpIfBitsSet(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 2, + }, + bpf.JumpIf{ + Cond: bpf.JumpBitsSet, + Val: 0x1122, + SkipTrue: 1, + }, + bpf.RetConstant{ + Val: 0, + }, + bpf.RetConstant{ + Val: 10, + }, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0x01, 0x02, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 2, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMJumpIfBitsNotSet(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 2, + }, + bpf.JumpIf{ + Cond: bpf.JumpBitsNotSet, + Val: 0x1221, + SkipTrue: 1, + }, + bpf.RetConstant{ + Val: 0, + }, + bpf.RetConstant{ + Val: 10, + }, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0x01, 0x02, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 2, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_load_test.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_load_test.go new file mode 100644 index 000000000..04578b66b --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_load_test.go @@ -0,0 +1,246 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package bpf_test + +import ( + "net" + "testing" + + "golang.org/x/net/bpf" + "golang.org/x/net/ipv4" +) + +func TestVMLoadAbsoluteOffsetOutOfBounds(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 100, + Size: 2, + }, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0, 1, 2, 3, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 0, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMLoadAbsoluteOffsetPlusSizeOutOfBounds(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 2, + }, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 0, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMLoadAbsoluteBadInstructionSize(t *testing.T) { + _, _, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Size: 5, + }, + bpf.RetA{}, + }) + if errStr(err) != "assembling instruction 1: invalid load byte length 0" { + t.Fatalf("unexpected error: %v", err) + } +} + +func TestVMLoadConstantOK(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadConstant{ + Dst: bpf.RegX, + Val: 9, + }, + bpf.TXA{}, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 1, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMLoadIndirectOutOfBounds(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadIndirect{ + Off: 100, + Size: 1, + }, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 0, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMLoadMemShiftOutOfBounds(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadMemShift{ + Off: 100, + }, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 0, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +const ( + dhcp4Port = 53 +) + +func TestVMLoadMemShiftLoadIndirectNoResult(t *testing.T) { + vm, in, done := testDHCPv4(t) + defer done() + + // Append mostly empty UDP header with incorrect DHCPv4 port + in = append(in, []byte{ + 0, 0, + 0, dhcp4Port + 1, + 0, 0, + 0, 0, + }...) + + out, err := vm.Run(in) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 0, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMLoadMemShiftLoadIndirectOK(t *testing.T) { + vm, in, done := testDHCPv4(t) + defer done() + + // Append mostly empty UDP header with correct DHCPv4 port + in = append(in, []byte{ + 0, 0, + 0, dhcp4Port, + 0, 0, + 0, 0, + }...) + + out, err := vm.Run(in) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := len(in)-8, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func testDHCPv4(t *testing.T) (virtualMachine, []byte, func()) { + // DHCPv4 test data courtesy of David Anderson: + // https://github.com/google/netboot/blob/master/dhcp4/conn_linux.go#L59-L70 + vm, done, err := testVM(t, []bpf.Instruction{ + // Load IPv4 packet length + bpf.LoadMemShift{Off: 8}, + // Get UDP dport + bpf.LoadIndirect{Off: 8 + 2, Size: 2}, + // Correct dport? + bpf.JumpIf{Cond: bpf.JumpEqual, Val: dhcp4Port, SkipFalse: 1}, + // Accept + bpf.RetConstant{Val: 1500}, + // Ignore + bpf.RetConstant{Val: 0}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + + // Minimal requirements to make a valid IPv4 header + h := &ipv4.Header{ + Len: ipv4.HeaderLen, + Src: net.IPv4(192, 168, 1, 1), + Dst: net.IPv4(192, 168, 1, 2), + } + hb, err := h.Marshal() + if err != nil { + t.Fatalf("failed to marshal IPv4 header: %v", err) + } + + hb = append([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + }, hb...) + + return vm, hb, done +} diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_ret_test.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_ret_test.go new file mode 100644 index 000000000..2d86eae3e --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_ret_test.go @@ -0,0 +1,115 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package bpf_test + +import ( + "testing" + + "golang.org/x/net/bpf" +) + +func TestVMRetA(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 9, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 1, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMRetALargerThanInput(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadAbsolute{ + Off: 8, + Size: 2, + }, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0, 255, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 2, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMRetConstant(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.RetConstant{ + Val: 9, + }, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0, 1, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 1, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMRetConstantLargerThanInput(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.RetConstant{ + Val: 16, + }, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0, 1, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 2, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_scratch_test.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_scratch_test.go new file mode 100644 index 000000000..e600e3c28 --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_scratch_test.go @@ -0,0 +1,247 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package bpf_test + +import ( + "testing" + + "golang.org/x/net/bpf" +) + +func TestVMStoreScratchInvalidScratchRegisterTooSmall(t *testing.T) { + _, _, err := testVM(t, []bpf.Instruction{ + bpf.StoreScratch{ + Src: bpf.RegA, + N: -1, + }, + bpf.RetA{}, + }) + if errStr(err) != "assembling instruction 1: invalid scratch slot -1" { + t.Fatalf("unexpected error: %v", err) + } +} + +func TestVMStoreScratchInvalidScratchRegisterTooLarge(t *testing.T) { + _, _, err := testVM(t, []bpf.Instruction{ + bpf.StoreScratch{ + Src: bpf.RegA, + N: 16, + }, + bpf.RetA{}, + }) + if errStr(err) != "assembling instruction 1: invalid scratch slot 16" { + t.Fatalf("unexpected error: %v", err) + } +} + +func TestVMStoreScratchUnknownSourceRegister(t *testing.T) { + _, _, err := testVM(t, []bpf.Instruction{ + bpf.StoreScratch{ + Src: 100, + N: 0, + }, + bpf.RetA{}, + }) + if errStr(err) != "assembling instruction 1: invalid source register 100" { + t.Fatalf("unexpected error: %v", err) + } +} + +func TestVMLoadScratchInvalidScratchRegisterTooSmall(t *testing.T) { + _, _, err := testVM(t, []bpf.Instruction{ + bpf.LoadScratch{ + Dst: bpf.RegX, + N: -1, + }, + bpf.RetA{}, + }) + if errStr(err) != "assembling instruction 1: invalid scratch slot -1" { + t.Fatalf("unexpected error: %v", err) + } +} + +func TestVMLoadScratchInvalidScratchRegisterTooLarge(t *testing.T) { + _, _, err := testVM(t, []bpf.Instruction{ + bpf.LoadScratch{ + Dst: bpf.RegX, + N: 16, + }, + bpf.RetA{}, + }) + if errStr(err) != "assembling instruction 1: invalid scratch slot 16" { + t.Fatalf("unexpected error: %v", err) + } +} + +func TestVMLoadScratchUnknownDestinationRegister(t *testing.T) { + _, _, err := testVM(t, []bpf.Instruction{ + bpf.LoadScratch{ + Dst: 100, + N: 0, + }, + bpf.RetA{}, + }) + if errStr(err) != "assembling instruction 1: invalid target register 100" { + t.Fatalf("unexpected error: %v", err) + } +} + +func TestVMStoreScratchLoadScratchOneValue(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + // Load byte 255 + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + // Copy to X and store in scratch[0] + bpf.TAX{}, + bpf.StoreScratch{ + Src: bpf.RegX, + N: 0, + }, + // Load byte 1 + bpf.LoadAbsolute{ + Off: 9, + Size: 1, + }, + // Overwrite 1 with 255 from scratch[0] + bpf.LoadScratch{ + Dst: bpf.RegA, + N: 0, + }, + // Return 255 + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 255, 1, 2, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 3, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} + +func TestVMStoreScratchLoadScratchMultipleValues(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + // Load byte 10 + bpf.LoadAbsolute{ + Off: 8, + Size: 1, + }, + // Store in scratch[0] + bpf.StoreScratch{ + Src: bpf.RegA, + N: 0, + }, + // Load byte 20 + bpf.LoadAbsolute{ + Off: 9, + Size: 1, + }, + // Store in scratch[1] + bpf.StoreScratch{ + Src: bpf.RegA, + N: 1, + }, + // Load byte 30 + bpf.LoadAbsolute{ + Off: 10, + Size: 1, + }, + // Store in scratch[2] + bpf.StoreScratch{ + Src: bpf.RegA, + N: 2, + }, + // Load byte 1 + bpf.LoadAbsolute{ + Off: 11, + Size: 1, + }, + // Store in scratch[3] + bpf.StoreScratch{ + Src: bpf.RegA, + N: 3, + }, + // Load in byte 10 to X + bpf.LoadScratch{ + Dst: bpf.RegX, + N: 0, + }, + // Copy X -> A + bpf.TXA{}, + // Verify value is 10 + bpf.JumpIf{ + Cond: bpf.JumpEqual, + Val: 10, + SkipTrue: 1, + }, + // Fail test if incorrect + bpf.RetConstant{ + Val: 0, + }, + // Load in byte 20 to A + bpf.LoadScratch{ + Dst: bpf.RegA, + N: 1, + }, + // Verify value is 20 + bpf.JumpIf{ + Cond: bpf.JumpEqual, + Val: 20, + SkipTrue: 1, + }, + // Fail test if incorrect + bpf.RetConstant{ + Val: 0, + }, + // Load in byte 30 to A + bpf.LoadScratch{ + Dst: bpf.RegA, + N: 2, + }, + // Verify value is 30 + bpf.JumpIf{ + Cond: bpf.JumpEqual, + Val: 30, + SkipTrue: 1, + }, + // Fail test if incorrect + bpf.RetConstant{ + Val: 0, + }, + // Return first two bytes on success + bpf.RetConstant{ + Val: 10, + }, + }) + if err != nil { + t.Fatalf("failed to load BPF program: %v", err) + } + defer done() + + out, err := vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 10, 20, 30, 1, + }) + if err != nil { + t.Fatalf("unexpected error while running program: %v", err) + } + if want, got := 2, out; want != got { + t.Fatalf("unexpected number of output bytes:\n- want: %d\n- got: %d", + want, got) + } +} diff --git a/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_test.go b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_test.go new file mode 100644 index 000000000..6bd4dd5c3 --- /dev/null +++ b/vendor/github.com/miekg/dns/vendor/golang.org/x/net/bpf/vm_test.go @@ -0,0 +1,144 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package bpf_test + +import ( + "fmt" + "testing" + + "golang.org/x/net/bpf" +) + +var _ bpf.Instruction = unknown{} + +type unknown struct{} + +func (unknown) Assemble() (bpf.RawInstruction, error) { + return bpf.RawInstruction{}, nil +} + +func TestVMUnknownInstruction(t *testing.T) { + vm, done, err := testVM(t, []bpf.Instruction{ + bpf.LoadConstant{ + Dst: bpf.RegA, + Val: 100, + }, + // Should terminate the program with an error immediately + unknown{}, + bpf.RetA{}, + }) + if err != nil { + t.Fatalf("unexpected error: %v", err) + } + defer done() + + _, err = vm.Run([]byte{ + 0xff, 0xff, 0xff, 0xff, + 0xff, 0xff, 0xff, 0xff, + 0x00, 0x00, + }) + if errStr(err) != "unknown Instruction at index 1: bpf_test.unknown" { + t.Fatalf("unexpected error while running program: %v", err) + } +} + +func TestVMNoReturnInstruction(t *testing.T) { + _, _, err := testVM(t, []bpf.Instruction{ + bpf.LoadConstant{ + Dst: bpf.RegA, + Val: 1, + }, + }) + if errStr(err) != "BPF program must end with RetA or RetConstant" { + t.Fatalf("unexpected error: %v", err) + } +} + +func TestVMNoInputInstructions(t *testing.T) { + _, _, err := testVM(t, []bpf.Instruction{}) + if errStr(err) != "one or more Instructions must be specified" { + t.Fatalf("unexpected error: %v", err) + } +} + +// ExampleNewVM demonstrates usage of a VM, using an Ethernet frame +// as input and checking its EtherType to determine if it should be accepted. +func ExampleNewVM() { + // Offset | Length | Comment + // ------------------------- + // 00 | 06 | Ethernet destination MAC address + // 06 | 06 | Ethernet source MAC address + // 12 | 02 | Ethernet EtherType + const ( + etOff = 12 + etLen = 2 + + etARP = 0x0806 + ) + + // Set up a VM to filter traffic based on if its EtherType + // matches the ARP EtherType. + vm, err := bpf.NewVM([]bpf.Instruction{ + // Load EtherType value from Ethernet header + bpf.LoadAbsolute{ + Off: etOff, + Size: etLen, + }, + // If EtherType is equal to the ARP EtherType, jump to allow + // packet to be accepted + bpf.JumpIf{ + Cond: bpf.JumpEqual, + Val: etARP, + SkipTrue: 1, + }, + // EtherType does not match the ARP EtherType + bpf.RetConstant{ + Val: 0, + }, + // EtherType matches the ARP EtherType, accept up to 1500 + // bytes of packet + bpf.RetConstant{ + Val: 1500, + }, + }) + if err != nil { + panic(fmt.Sprintf("failed to load BPF program: %v", err)) + } + + // Create an Ethernet frame with the ARP EtherType for testing + frame := []byte{ + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, + 0x00, 0x11, 0x22, 0x33, 0x44, 0x55, + 0x08, 0x06, + // Payload omitted for brevity + } + + // Run our VM's BPF program using the Ethernet frame as input + out, err := vm.Run(frame) + if err != nil { + panic(fmt.Sprintf("failed to accept Ethernet frame: %v", err)) + } + + // BPF VM can return a byte count greater than the number of input + // bytes, so trim the output to match the input byte length + if out > len(frame) { + out = len(frame) + } + + fmt.Printf("out: %d bytes", out) + + // Output: + // out: 14 bytes +} + +// errStr returns the string representation of an error, or +// "<nil>" if it is nil. +func errStr(err error) string { + if err == nil { + return "<nil>" + } + + return err.Error() +} |