BPF Instruction Set Specification, v1.0 Microsoft
Redmond 98052 USA WA dave.thaler.ietf@gmail.com
This document specifies version 1.0 of the BPF instruction set.
For brevity and consistency, this document refers to families of types using a shorthand syntax and refers to several expository, mnemonic functions when describing the semantics of instructions. The range of valid values for those types and the semantics of those functions are defined in the following subsections.
This document refers to integer types with the notation SN to specify a type's signedness (S) and bit width (N), respectively. Meaning of signedness notation.
S Meaning
u unsigned
s signed
Meaning of bit-width notation.
N Bit width
8 8 bits
16 16 bits
32 32 bits
64 64 bits
128 128 bits
For example, u32 is a type whose valid values are all the 32-bit unsigned numbers and s16 is a types whose valid values are all the 16-bit signed numbers.
  • htobe16: Takes an unsigned 16-bit number in host-endian format and returns the equivalent number as an unsigned 16-bit number in big-endian format.
  • htobe32: Takes an unsigned 32-bit number in host-endian format and returns the equivalent number as an unsigned 32-bit number in big-endian format.
  • htobe64: Takes an unsigned 64-bit number in host-endian format and returns the equivalent number as an unsigned 64-bit number in big-endian format.
  • htole16: Takes an unsigned 16-bit number in host-endian format and returns the equivalent number as an unsigned 16-bit number in little-endian format.
  • htole32: Takes an unsigned 32-bit number in host-endian format and returns the equivalent number as an unsigned 32-bit number in little-endian format.
  • htole64: Takes an unsigned 64-bit number in host-endian format and returns the equivalent number as an unsigned 64-bit number in little-endian format.
  • bswap16: Takes an unsigned 16-bit number in either big- or little-endian format and returns the equivalent number with the same bit width but opposite endianness.
  • bswap32: Takes an unsigned 32-bit number in either big- or little-endian format and returns the equivalent number with the same bit width but opposite endianness.
  • bswap64: Takes an unsigned 64-bit number in either big- or little-endian format and returns the equivalent number with the same bit width but opposite endianness.
Sign Extend
To sign extend an X -bit number, A, to a Y -bit number, B , means to
  1. Copy all X bits from A to the lower X bits of B.
  2. Set the value of the remaining Y - X bits of B to the value of the most-significant bit of A.
BPF has two instruction encodings:
  • the basic instruction encoding, which uses 64 bits to encode an instruction
  • the wide instruction encoding, which appends a second 64-bit immediate (i.e., constant) value after the basic instruction for a total of 128 bits.
The fields conforming an encoded basic instruction are stored in the following order: opcode:8 src_reg:4 dst_reg:4 offset:16 imm:32 // In little-endian BPF. opcode:8 dst_reg:4 src_reg:4 offset:16 imm:32 // In big-endian BPF.
imm
signed integer immediate value
offset
signed integer offset used with pointer arithmetic
src_reg
the source register number (0-10), except where otherwise specified (64-bit immediate instructions reuse this field for other purposes)
dst_reg
destination register number (0-10)
opcode
operation to perform
Note that the contents of multi-byte fields ('imm' and 'offset') are stored using big-endian byte ordering in big-endian BPF and little-endian byte ordering in little-endian BPF. For example: opcode offset imm assembly src_reg dst_reg 07 0 1 00 00 44 33 22 11 r1 += 0x11223344 // little dst_reg src_reg 07 1 0 00 00 11 22 33 44 r1 += 0x11223344 // big Note that most instructions do not use all of the fields. Unused fields shall be cleared to zero. As discussed below in 64-bit immediate instructions, a 64-bit immediate instruction uses a 64-bit immediate value that is constructed as follows. The 64 bits following the basic instruction contain a pseudo instruction using the same format but with opcode, dst_reg, src_reg, and offset all set to zero, and imm containing the high 32 bits of the immediate value. This is depicted in the following figure: basic_instruction .-----------------------------. | | code:8 regs:8 offset:16 imm:32 unused:32 imm:32 | | '--------------' pseudo instruction Thus the 64-bit immediate value is constructed as follows:
imm64 = (next_imm << 32) | imm
where 'next_imm' refers to the imm value of the pseudo instruction following the basic instruction. The unused bytes in the pseudo instruction are reserved and shall be cleared to zero.
The three LSB bits of the 'opcode' field store the instruction class:
class value description reference
BPF_LD 0x00 non-standard load operations Load and store instructions
BPF_LDX 0x01 load into register operations Load and store instructions
BPF_ST 0x02 store from immediate operations Load and store instructions
BPF_STX 0x03 store from register operations Load and store instructions
BPF_ALU 0x04 32-bit arithmetic operations Arithmetic and jump instructions
BPF_JMP 0x05 64-bit jump operations Arithmetic and jump instructions
BPF_JMP32 0x06 32-bit jump operations Arithmetic and jump instructions
BPF_ALU64 0x07 64-bit arithmetic operations Arithmetic and jump instructions
For arithmetic and jump instructions (BPF_ALU, BPF_ALU64, BPF_JMP and BPF_JMP32), the 8-bit 'opcode' field is divided into three parts:
4 bits (MSB) 1 bit 3 bits (LSB)
code source instruction class
code
the operation code, whose meaning varies by instruction class
source
the source operand location, which unless otherwise specified is one of:
source value description
BPF_K 0x00 use 32-bit 'imm' value as source operand
BPF_X 0x08 use 'src_reg' register value as source operand
instruction class
the instruction class (see Instruction classes)
BPF_ALU uses 32-bit wide operands while BPF_ALU64 uses 64-bit wide operands for otherwise identical operations. The 'code' field encodes the operation as below, where 'src' and 'dst' refer to the values of the source and destination registers, respectively.
code value offset description
BPF_ADD 0x00 0 dst += src
BPF_SUB 0x10 0 dst -= src
BPF_MUL 0x20 0 dst *= src
BPF_DIV 0x30 0 dst = (src != 0) ? (dst / src) : 0
BPF_SDIV 0x30 1 dst = (src != 0) ? (dst s/ src) : 0
BPF_OR 0x40 0 dst |= src
BPF_AND 0x50 0 dst &= src
BPF_LSH 0x60 0 dst <<= (src & mask)
BPF_RSH 0x70 0 dst >>= (src & mask)
BPF_NEG 0x80 0 dst = -dst
BPF_MOD 0x90 0 dst = (src != 0) ? (dst % src) : dst
BPF_SMOD 0x90 1 dst = (src != 0) ? (dst s% src) : dst
BPF_XOR 0xa0 0 dst ^= src
BPF_MOV 0xb0 0 dst = src
BPF_MOVSX 0xb0 8/16/32 dst = (s8,s16,s32)src
BPF_ARSH 0xc0 0 sign extending dst >>= (src & mask)
BPF_END 0xd0 0 byte swap operations (see Byte swap instructions below)
Underflow and overflow are allowed during arithmetic operations, meaning the 64-bit or 32-bit value will wrap. If BPF program execution would result in division by zero, the destination register is instead set to zero. If execution would result in modulo by zero, for BPF_ALU64 the value of the destination register is unchanged whereas for BPF_ALU the upper 32 bits of the destination register are zeroed. BPF_ADD | BPF_X | BPF_ALU means: dst = (u32) ((u32) dst + (u32) src) where '(u32)' indicates that the upper 32 bits are zeroed. BPF_ADD | BPF_X | BPF_ALU64 means: dst = dst + src BPF_XOR | BPF_K | BPF_ALU means: dst = (u32) dst ^ (u32) imm32 BPF_XOR | BPF_K | BPF_ALU64 means: dst = dst ^ imm32 Note that most instructions have instruction offset of 0. Only three instructions (BPF_SDIV, BPF_SMOD, BPF_MOVSX) have a non-zero offset. The division and modulo operations support both unsigned and signed flavors. For unsigned operations (BPF_DIV and BPF_MOD), for BPF_ALU, 'imm' is interpreted as a 32-bit unsigned value. For BPF_ALU64, 'imm' is first sign extended from 32 to 64 bits, and then interpreted as a 64-bit unsigned value. For signed operations (BPF_SDIV and BPF_SMOD), for BPF_ALU, 'imm' is interpreted as a 32-bit signed value. For BPF_ALU64, 'imm' is first sign extended from 32 to 64 bits, and then interpreted as a 64-bit signed value. Note that there are varying definitions of the signed modulo operation when the dividend or divisor are negative, where implementations often vary by language such that Python, Ruby, etc. differ from C, Go, Java, etc. This specification requires that signed modulo use truncated division (where -13 % 3 == -1) as implemented in C, Go, etc.:
a % n = a - n * trunc(a / n)
The BPF_MOVSX instruction does a move operation with sign extension. BPF_ALU | BPF_MOVSX sign extends 8-bit and 16-bit operands into 32 bit operands, and zeroes the remaining upper 32 bits. BPF_ALU64 | BPF_MOVSX sign extends 8-bit, 16-bit, and 32-bit operands into 64 bit operands. Shift operations use a mask of 0x3F (63) for 64-bit operations and 0x1F (31) for 32-bit operations.
The byte swap instructions use instruction classes of BPF_ALU and BPF_ALU64 and a 4-bit 'code' field of BPF_END. The byte swap instructions operate on the destination register only and do not use a separate source register or immediate value. For BPF_ALU, the 1-bit source operand field in the opcode is used to select what byte order the operation converts from or to. For BPF_ALU64, the 1-bit source operand field in the opcode is reserved and must be set to 0.
class source value description
BPF_ALU BPF_TO_LE 0x00 convert between host byte order and little endian
BPF_ALU BPF_TO_BE 0x08 convert between host byte order and big endian
BPF_ALU64 Reserved 0x00 do byte swap unconditionally
The 'imm' field encodes the width of the swap operations. The following widths are supported: 16, 32 and 64. Examples: BPF_ALU | BPF_TO_LE | BPF_END with imm = 16/32/64 means: dst = htole16(dst) dst = htole32(dst) dst = htole64(dst) BPF_ALU | BPF_TO_BE | BPF_END with imm = 16/32/64 means: dst = htobe16(dst) dst = htobe32(dst) dst = htobe64(dst) BPF_ALU64 | BPF_TO_LE | BPF_END with imm = 16/32/64 means: dst = bswap16(dst) dst = bswap32(dst) dst = bswap64(dst)
BPF_JMP32 uses 32-bit wide operands while BPF_JMP uses 64-bit wide operands for otherwise identical operations. The 'code' field encodes the operation as below:
code value src description notes
BPF_JA 0x0 0x0 PC += offset BPF_JMP class
BPF_JA 0x0 0x0 PC += imm BPF_JMP32 class
BPF_JEQ 0x1 any PC += offset if dst == src
BPF_JGT 0x2 any PC += offset if dst > src unsigned
BPF_JGE 0x3 any PC += offset if dst >= src unsigned
BPF_JSET 0x4 any PC += offset if dst & src
BPF_JNE 0x5 any PC += offset if dst != src
BPF_JSGT 0x6 any PC += offset if dst > src signed
BPF_JSGE 0x7 any PC += offset if dst >= src signed
BPF_CALL 0x8 0x0 call helper function by address see Helper functions
BPF_CALL 0x8 0x1 call PC += imm see Program-local functions
BPF_CALL 0x8 0x2 call helper function by BTF ID see Helper functions
BPF_EXIT 0x9 0x0 return BPF_JMP only
BPF_JLT 0xa any PC += offset if dst < src unsigned
BPF_JLE 0xb any PC += offset if dst <= src unsigned
BPF_JSLT 0xc any PC += offset if dst < src signed
BPF_JSLE 0xd any PC += offset if dst <= src signed
The BPF program needs to store the return value into register R0 before doing a BPF_EXIT. Example: BPF_JSGE | BPF_X | BPF_JMP32 (0x7e) means: if (s32)dst s>= (s32)src goto +offset where 's>=' indicates a signed '>=' comparison. BPF_JA | BPF_K | BPF_JMP32 (0x06) means: gotol +imm where 'imm' means the branch offset comes from insn 'imm' field. Note that there are two flavors of BPF_JA instructions. The BPF_JMP class permits a 16-bit jump offset specified by the 'offset' field, whereas the BPF_JMP32 class permits a 32-bit jump offset specified by the 'imm' field. A > 16-bit conditional jump may be converted to a < 16-bit conditional jump plus a 32-bit unconditional jump.
Helper functions are a concept whereby BPF programs can call into a set of function calls exposed by the underlying platform. Historically, each helper function was identified by an address encoded in the imm field. The available helper functions may differ for each program type, but address values are unique across all program types. Platforms that support the BPF Type Format (BTF) support identifying a helper function by a BTF ID encoded in the imm field, where the BTF ID identifies the helper name and type.
Program-local functions are functions exposed by the same BPF program as the caller, and are referenced by offset from the call instruction, similar to BPF_JA. The offset is encoded in the imm field of the call instruction. A BPF_EXIT within the program-local function will return to the caller.
For load and store instructions (BPF_LD, BPF_LDX, BPF_ST, and BPF_STX), the 8-bit 'opcode' field is divided as:
3 bits (MSB) 2 bits 3 bits (LSB)
mode size instruction class
The mode modifier is one of:
mode modifier value description reference
BPF_IMM 0x00 64-bit immediate instructions 64-bit immediate instructions
BPF_ABS 0x20 legacy BPF packet access (absolute) Legacy BPF Packet access instructions
BPF_IND 0x40 legacy BPF packet access (indirect) Legacy BPF Packet access instructions
BPF_MEM 0x60 regular load and store operations Regular load and store operations
BPF_MEMSX 0x80 sign-extension load operations Sign-extension load operations
BPF_ATOMIC 0xc0 atomic operations Atomic operations
The size modifier is one of:
size modifier value description
BPF_W 0x00 word (4 bytes)
BPF_H 0x08 half word (2 bytes)
BPF_B 0x10 byte
BPF_DW 0x18 double word (8 bytes)
The BPF_MEM mode modifier is used to encode regular load and store instructions that transfer data between a register and memory. BPF_MEM | <size> | BPF_STX means: *(size *) (dst + offset) = src BPF_MEM | <size> | BPF_ST means: *(size *) (dst + offset) = imm32 BPF_MEM | <size> | BPF_LDX means: dst = *(unsigned size *) (src + offset) Where size is one of: BPF_B, BPF_H, BPF_W, or BPF_DW and 'unsigned size' is one of u8, u16, u32 or u64.
The BPF_MEMSX mode modifier is used to encode sign-extension load instructions that transfer data between a register and memory. BPF_MEMSX | <size> | BPF_LDX means: dst = *(signed size *) (src + offset) Where size is one of: BPF_B, BPF_H or BPF_W, and 'signed size' is one of s8, s16 or s32.
Atomic operations are operations that operate on memory and can not be interrupted or corrupted by other access to the same memory region by other BPF programs or means outside of this specification. All atomic operations supported by BPF are encoded as store operations that use the BPF_ATOMIC mode modifier as follows:
  • BPF_ATOMIC | BPF_W | BPF_STX for 32-bit operations
  • BPF_ATOMIC | BPF_DW | BPF_STX for 64-bit operations
  • 8-bit and 16-bit wide atomic operations are not supported.
The 'imm' field is used to encode the actual atomic operation. Simple atomic operation use a subset of the values defined to encode arithmetic operations in the 'imm' field to encode the atomic operation:
imm value description
BPF_ADD 0x00 atomic add
BPF_OR 0x40 atomic or
BPF_AND 0x50 atomic and
BPF_XOR 0xa0 atomic xor
BPF_ATOMIC | BPF_W | BPF_STX with 'imm' = BPF_ADD means: *(u32 *)(dst + offset) += src BPF_ATOMIC | BPF_DW | BPF_STX with 'imm' = BPF ADD means: *(u64 *)(dst + offset) += src In addition to the simple atomic operations, there also is a modifier and two complex atomic operations:
imm value description
BPF_FETCH 0x01 modifier: return old value
BPF_XCHG 0xe0 | BPF_FETCH atomic exchange
BPF_CMPXCHG 0xf0 | BPF_FETCH atomic compare and exchange
The BPF_FETCH modifier is optional for simple atomic operations, and always set for the complex atomic operations. If the BPF_FETCH flag is set, then the operation also overwrites src with the value that was in memory before it was modified. The BPF_XCHG operation atomically exchanges src with the value addressed by dst + offset. The BPF_CMPXCHG operation atomically compares the value addressed by dst + offset with R0. If they match, the value addressed by dst + offset is replaced with src. In either case, the value that was at dst + offset before the operation is zero-extended and loaded back to R0.
Instructions with the BPF_IMM 'mode' modifier use the wide instruction encoding defined in Instruction encoding, and use the 'src' field of the basic instruction to hold an opcode subtype. The following table defines a set of BPF_IMM | BPF_DW | BPF_LD instructions with opcode subtypes in the 'src' field, using new terms such as "map" defined further below:
opcode construction opcode src pseudocode imm type dst type
BPF_IMM | BPF_DW | BPF_LD 0x18 0x0 dst = imm64 integer integer
BPF_IMM | BPF_DW | BPF_LD 0x18 0x1 dst = map_by_fd(imm) map fd map
BPF_IMM | BPF_DW | BPF_LD 0x18 0x2 dst = map_val(map_by_fd(imm)) + next_imm map fd data pointer
BPF_IMM | BPF_DW | BPF_LD 0x18 0x3 dst = var_addr(imm) variable id data pointer
BPF_IMM | BPF_DW | BPF_LD 0x18 0x4 dst = code_addr(imm) integer code pointer
BPF_IMM | BPF_DW | BPF_LD 0x18 0x5 dst = map_by_idx(imm) map index map
BPF_IMM | BPF_DW | BPF_LD 0x18 0x6 dst = map_val(map_by_idx(imm)) + next_imm map index data pointer
where
  • map_by_fd(imm) means to convert a 32-bit file descriptor into an address of a map (see Maps)
  • map_by_idx(imm) means to convert a 32-bit index into an address of a map
  • map_val(map) gets the address of the first value in a given map
  • var_addr(imm) gets the address of a platform variable (see Platform Variables) with a given id
  • code_addr(imm) gets the address of the instruction at a specified relative offset in number of (64-bit) instructions
  • the 'imm type' can be used by disassemblers for display
  • the 'dst type' can be used for verification and JIT compilation purposes
Maps are shared memory regions accessible by BPF programs on some platforms. A map can have various semantics as defined in a separate document, and may or may not have a single contiguous memory region, but the 'map_val(map)' is currently only defined for maps that do have a single contiguous memory region. Each map can have a file descriptor (fd) if supported by the platform, where 'map_by_fd(imm)' means to get the map with the specified file descriptor. Each BPF program can also be defined to use a set of maps associated with the program at load time, and 'map_by_idx(imm)' means to get the map with the given index in the set associated with the BPF program containing the instruction.
Platform variables are memory regions, identified by integer ids, exposed by the runtime and accessible by BPF programs on some platforms. The 'var_addr(imm)' operation means to get the address of the memory region identified by the given id.
BPF previously introduced special instructions for access to packet data that were carried over from classic BPF. However, these instructions are deprecated and should no longer be used.
This document proposes a new IANA registry for BPF instructions, as follows:
  • Name of the registry: BPF Instruction Set
  • Name of the registry group: same as registry name
  • Required information for registrations: The values to appear in the entry fields.
  • Syntax of registry entries: Each entry has the following fields:
    • opcode: a 1-byte value in hex format indicating the value of the opcode field
    • src: either a value indicating the value of the src field, or "any"
    • imm: either a value indicating the value of the imm field, or "any"
    • offset: either a value indicating the value of the offset field, or "any"
    • description: description of what the instruction does, typically in pseudocode
    • reference: a reference to the defining specification
    • status: Permanent, Provisional, or Historical
  • Registration policy (see RFC 8126 section 4 for details):
    • Permanent: Standards action or IESG Review
    • Provisional: Specification required
    • Historical: Specification required
  • Initial registrations: See the Appendix. Instructions other than those listed as deprecated are Permanent. Any listed as deprecated are Historical.
This draft was generated from instruction-set.rst in the Linux kernel repository, to which a number of other individuals have authored contributions over time, including Akhil Raj, Alexei Starovoitov, Brendan Jackman, Christoph Hellwig, Daniel Borkmann, Ilya Leoshkevich, Jiong Wang, Jose E. Marchesi, Kosuke Fujimoto, Shahab Vahedi, Tiezhu Yang, Will Hawkins, and Zheng Yejian, with review and suggestions by many others including Alan Jowett, Andrii Nakryiko, David Vernet, Jim Harris, Quentin Monnet, Song Liu, Shung-Hsi Yu, Stanislav Fomichev, and Yonghong Song.
Initial values for the BPF Instruction registry are given below. The descriptions in this table are informative. In case of any discrepancy, the reference is authoritative.
opcode src imm offset description reference
0x00 0x0 any 0 (additional immediate value) 64-bit immediate instructions
0x04 0x0 any 0 dst = (u32)((u32)dst + (u32)imm) Arithmetic instructions
0x05 0x0 0x00 any goto +offset Jump instructions
0x06 0x0 any 0 goto +imm Jump instructions
0x07 0x0 any 0 dst += imm Arithmetic instructions
0x0c any 0x00 0 dst = (u32)((u32)dst + (u32)src) Arithmetic instructions
0x0f any 0x00 0 dst += src Arithmetic instructions
0x14 0x0 any 0 dst = (u32)((u32)dst - (u32)imm) Arithmetic instructions
0x15 0x0 any any if dst == imm goto +offset Jump instructions
0x16 0x0 any any if (u32)dst == imm goto +offset Jump instructions
0x17 0x0 any 0 dst -= imm Arithmetic instructions
0x18 0x0 any 0 dst = imm64 64-bit immediate instructions
0x18 0x1 any 0 dst = map_by_fd(imm) 64-bit immediate instructions
0x18 0x2 any 0 dst = mva(map_by_fd(imm)) + next_imm 64-bit immediate instructions
0x18 0x3 any 0 dst = variable_addr(imm) 64-bit immediate instructions
0x18 0x4 any 0 dst = code_addr(imm) 64-bit immediate instructions
0x18 0x5 any 0 dst = map_by_idx(imm) 64-bit immediate instructions
0x18 0x6 any 0 dst = mva(map_by_idx(imm)) + next_imm 64-bit immediate instructions
0x1c any 0x00 0 dst = (u32)((u32)dst - (u32)src) Arithmetic instructions
0x1d any 0x00 any if dst == src goto +offset Jump instructions
0x1e any 0x00 any if (u32)dst == (u32)src goto +offset Jump instructions
0x1f any 0x00 0 dst -= src Arithmetic instructions
0x20 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x21 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x22 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x23 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x24 0x0 any 0 dst = (u32)(dst * imm) Arithmetic instructions
0x25 0x0 any any if dst > imm goto +offset Jump instructions
0x26 0x0 any any if (u32)dst > imm goto +offset Jump instructions
0x27 0x0 any 0 dst *= imm Arithmetic instructions
0x28 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x29 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x2a any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x2b any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x2c any 0x00 0 dst = (u32)(dst * src) Arithmetic instructions
0x2d any 0x00 any if dst > src goto +offset Jump instructions
0x2e any 0x00 any if (u32)dst > (u32)src goto +offset Jump instructions
0x2f any 0x00 0 dst *= src Arithmetic instructions
0x30 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x31 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x32 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x33 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x34 0x0 any 0 dst = (u32)((imm != 0) ? ((u32)dst / (u32)imm) : 0) Arithmetic instructions
0x34 0x0 any 1 dst = (u32)((imm != 0) ? ((s32)dst s/ imm) : 0) Arithmetic instructions
0x35 0x0 any any if dst >= imm goto +offset Jump instructions
0x36 0x0 any any if (u32)dst >= imm goto +offset Jump instructions
0x37 0x0 any 0 dst = (imm != 0) ? (dst / (u32)imm) : 0 Arithmetic instructions
0x37 0x0 any 1 dst = (imm != 0) ? (dst s/ imm) : 0 Arithmetic instructions
0x38 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x39 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x3a any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x3b any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x3c any any 0 dst = (u32)((src != 0) ? ((u32)dst / (u32)src) : 0) Arithmetic instructions
0x3c any any 1 dst = (u32)((src != 0) ? ((s32)dst s/(s32)src) : 0) Arithmetic instructions
0x3d any 0x00 any if dst >= src goto +offset Jump instructions
0x3e any 0x00 any if (u32)dst >= (u32)src goto +offset Jump instructions
0x3f any 0x00 0 dst = (src != 0) ? (dst / src) : 0 Arithmetic instructions
0x3f any 0x00 1 dst = (src != 0) ? (dst s/ src) : 0 Arithmetic instructions
0x40 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x41 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x42 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x43 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x44 0x0 any 0 dst = (u32)(dst | imm) Arithmetic instructions
0x45 0x0 any any if dst & imm goto +offset Jump instructions
0x46 0x0 any any if (u32)dst & imm goto +offset Jump instructions
0x47 0x0 any 0 dst |= imm Arithmetic instructions
0x48 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x49 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x4a any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x4b any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x4c any 0x00 0 dst = (u32)(dst | src) Arithmetic instructions
0x4d any 0x00 any if dst & src goto +offset Jump instructions
0x4e any 0x00 any if (u32)dst & (u32)src goto +offset Jump instructions
0x4f any 0x00 0 dst |= src Arithmetic instructions
0x50 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x51 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x52 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x53 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x54 0x0 any 0 dst = (u32)(dst & imm) Arithmetic instructions
0x55 0x0 any any if dst != imm goto +offset Jump instructions
0x56 0x0 any any if (u32)dst != imm goto +offset Jump instructions
0x57 0x0 any 0 dst &= imm Arithmetic instructions
0x58 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x59 any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x5a any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x5b any any any (deprecated, implementation-specific) Legacy BPF Packet access instructions
0x5c any 0x00 0 dst = (u32)(dst & src) Arithmetic instructions
0x5d any 0x00 any if dst != src goto +offset Jump instructions
0x5e any 0x00 any if (u32)dst != (u32)src goto +offset Jump instructions
0x5f any 0x00 0 dst &= src Arithmetic instructions
0x61 any 0x00 any dst = *(u32 *)(src + offset) Load and store instructions
0x62 0x0 any any *(u32 *)(dst + offset) = imm Load and store instructions
0x63 any 0x00 any *(u32 *)(dst + offset) = src Load and store instructions
0x64 0x0 any 0 dst = (u32)(dst << imm) Arithmetic instructions
0x65 0x0 any any if dst s> imm goto +offset Jump instructions
0x66 0x0 any any if (s32)dst s> (s32)imm goto +offset Jump instructions
0x67 0x0 any 0 dst <<= imm Arithmetic instructions
0x69 any 0x00 any dst = *(u16 *)(src + offset) Load and store instructions
0x6a 0x0 any any *(u16 *)(dst + offset) = imm Load and store instructions
0x6b any 0x00 any *(u16 *)(dst + offset) = src Load and store instructions
0x6c any 0x00 0 dst = (u32)(dst << src) Arithmetic instructions
0x6d any 0x00 any if dst s> src goto +offset Jump instructions
0x6e any 0x00 any if (s32)dst s> (s32)src goto +offset Jump instructions
0x6f any 0x00 0 dst <<= src Arithmetic instructions
0x71 any 0x00 any dst = *(u8 *)(src + offset) Load and store instructions
0x72 0x0 any any *(u8 *)(dst + offset) = imm Load and store instructions
0x73 any 0x00 any *(u8 *)(dst + offset) = src Load and store instructions
0x74 0x0 any 0 dst = (u32)(dst >> imm) Arithmetic instructions
0x75 0x0 any any if dst s>= imm goto +offset Jump instructions
0x76 0x0 any any if (s32)dst s>= (s32)imm goto +offset Jump instructions
0x77 0x0 any 0 dst >>= imm Arithmetic instructions
0x79 any 0x00 any dst = *(u64 *)(src + offset) Load and store instructions
0x7a 0x0 any any *(u64 *)(dst + offset) = imm Load and store instructions
0x7b any 0x00 any *(u64 *)(dst + offset) = src Load and store instructions
0x7c any 0x00 0 dst = (u32)(dst >> src) Arithmetic instructions
0x7d any 0x00 any if dst s>= src goto +offset Jump instructions
0x7e any 0x00 any if (s32)dst s>= (s32)src goto +offset Jump instructions
0x7f any 0x00 0 dst >>= src Arithmetic instructions
0x84 0x0 0x00 0 dst = (u32)-dst Arithmetic instructions
0x85 0x0 any 0 call helper function by address Helper functions
0x85 0x1 any 0 call PC += imm Program-local functions
0x85 0x2 any 0 call helper function by BTF ID Helper functions
0x87 0x0 0x00 0 dst = -dst Arithmetic instructions
0x94 0x0 any 0 dst = (u32)((imm != 0)?((u32)dst % (u32)imm) : dst) Arithmetic instructions
0x94 0x0 any 1 dst = (u32)((imm != 0) ? ((s32)dst s% imm) : dst) Arithmetic instructions
0x95 0x0 0x00 0 return Jump instructions
0x97 0x0 any 0 dst = (imm != 0) ? (dst % (u32)imm) : dst Arithmetic instructions
0x97 0x0 any 1 dst = (imm != 0) ? (dst s% imm) : dst Arithmetic instructions
0x9c any 0x00 0 dst = (u32)((src != 0)?((u32)dst % (u32)src) : dst) Arithmetic instructions
0x9c any 0x00 1 dst = (u32)((src != 0)?((s32)dst s% (s32)src) :dst) Arithmetic instructions
0x9f any 0x00 0 dst = (src != 0) ? (dst % src) : dst Arithmetic instructions
0x9f any 0x00 1 dst = (src != 0) ? (dst s% src) : dst Arithmetic instructions
0xa4 0x0 any 0 dst = (u32)(dst ^ imm) Arithmetic instructions
0xa5 0x0 any any if dst < imm goto +offset Jump instructions
0xa6 0x0 any any if (u32)dst < imm goto +offset Jump instructions
0xa7 0x0 any 0 dst ^= imm Arithmetic instructions
0xac any 0x00 0 dst = (u32)(dst ^ src) Arithmetic instructions
0xad any 0x00 any if dst < src goto +offset Jump instructions
0xae any 0x00 any if (u32)dst < (u32)src goto +offset Jump instructions
0xaf any 0x00 0 dst ^= src Arithmetic instructions
0xb4 0x0 any 0 dst = (u32) imm Arithmetic instructions
0xb4 0x0 any 8 dst = (u32) (s32) (s8) imm Arithmetic instructions
0xb4 0x0 any 16 dst = (u32) (s32) (s16) imm Arithmetic instructions
0xb5 0x0 any any if dst <= imm goto +offset Jump instructions
0xb6 0x0 any any if (u32)dst <= imm goto +offset Jump instructions
0xb7 0x0 any 0 dst = imm Arithmetic instructions
0xb7 0x0 any 8 dst = (s64) (s8) imm Arithmetic instructions
0xb7 0x0 any 16 dst = (s64) (s16) imm Arithmetic instructions
0xb7 0x0 any 32 dst = (s64) (s32) imm Arithmetic instructions
0xbc any 0x00 0 dst = (u32) src Arithmetic instructions
0xbc any 0x00 8 dst = (u32) (s32) (s8) src Arithmetic instructions
0xbc any 0x00 16 dst = (u32) (s32) (s16) src Arithmetic instructions
0xbd any 0x00 any if dst <= src goto +offset Jump instructions
0xbe any 0x00 any if (u32)dst <= (u32)src goto +offset Jump instructions
0xbf any 0x00 0 dst = src Arithmetic instructions
0xbf any 0x00 8 dst = (s64) (s8) src Arithmetic instructions
0xbf any 0x00 16 dst = (s64) (s16) src Arithmetic instructions
0xbf any 0x00 32 dst = (s64) (s32) src Arithmetic instructions
0xc3 any 0x00 any lock *(u32 *)(dst + offset) += src Atomic operations
0xc3 any 0x01 any lock: *(u32 *)(dst + offset) += src src = *(u32 *)(dst + offset) Atomic operations
0xc3 any 0x40 any *(u32 *)(dst + offset) |= src Atomic operations
0xc3 any 0x41 any lock: *(u32 *)(dst + offset) |= src src = *(u32 *)(dst + offset) Atomic operations
0xc3 any 0x50 any *(u32 *)(dst + offset) &= src Atomic operations
0xc3 any 0x51 any lock: *(u32 *)(dst + offset) &= src src = *(u32 *)(dst + offset) Atomic operations
0xc3 any 0xa0 any *(u32 *)(dst + offset) ^= src Atomic operations
0xc3 any 0xa1 any lock: *(u32 *)(dst + offset) ^= src src = *(u32 *)(dst + offset) Atomic operations
0xc3 any 0xe1 any lock: temp = *(u32 *)(dst + offset) *(u32 *)(dst + offset) = src src = temp Atomic operations
0xc3 any 0xf1 any lock: temp = *(u32 *)(dst + offset) if *(u32)(dst + offset) == R0 *(u32)(dst + offset) = src R0 = temp Atomic operations
0xc4 0x0 any 0 dst = (u32)(dst s>> imm) Arithmetic instructions
0xc5 0x0 any any if dst s< imm goto +offset Jump instructions
0xc6 0x0 any any if (s32)dst s< (s32)imm goto +offset Jump instructions
0xc7 0x0 any 0 dst s>>= imm Arithmetic instructions
0xcc any 0x00 0 dst = (u32)(dst s>> src) Arithmetic instructions
0xcd any 0x00 any if dst s< src goto +offset Jump instructions
0xce any 0x00 any if (s32)dst s< (s32)src goto +offset Jump instructions
0xcf any 0x00 0 dst s>>= src Arithmetic instructions
0xd4 0x0 0x10 0 dst = htole16(dst) Byte swap instructions
0xd4 0x0 0x20 0 dst = htole32(dst) Byte swap instructions
0xd4 0x0 0x40 0 dst = htole64(dst) Byte swap instructions
0xd5 0x0 any any if dst s<= imm goto +offset Jump instructions
0xd6 0x0 any any if (s32)dst s<= (s32)imm goto +offset Jump instructions
0xd7 0x0 0x10 0 dst = bswap16(dst) Byte swap instructions
0xd7 0x0 0x20 0 dst = bswap32(dst) Byte swap instructions
0xd7 0x0 0x40 0 dst = bswap64(dst) Byte swap instructions
0xdb any 0x00 any lock *(u64 *)(dst + offset) += src Atomic operations
0xdb any 0x01 any lock: *(u64 *)(dst + offset) += src src = *(u64 *)(dst + offset) Atomic operations
0xdb any 0x40 any *(u64 *)(dst + offset) |= src Atomic operations
0xdb any 0x41 any lock: *(u64 *)(dst + offset) |= src src = *(u64 *)(dst + offset) Atomic operations
0xdb any 0x50 any *(u64 *)(dst + offset) &= src Atomic operations
0xdb any 0x51 any lock: *(u64 *)(dst + offset) &= src src = *(u64 *)(dst + offset) Atomic operations
0xdb any 0xa0 any *(u64 *)(dst + offset) ^= src Atomic operations
0xdb any 0xa1 any lock: *(u64 *)(dst + offset) ^= src src = *(u64 *)(dst + offset) Atomic operations
0xdb any 0xe1 any lock: temp = *(u64 *)(dst + offset) *(u64 *)(dst + offset) = src src = temp Atomic operations
0xdb any 0xf1 any lock: temp = *(u64 *)(dst + offset) if *(u64)(dst + offset) == R0 *(u64)(dst + offset) = src R0 = temp Atomic operations
0xdc 0x0 0x10 0 dst = htobe16(dst) Byte swap instructions
0xdc 0x0 0x20 0 dst = htobe32(dst) Byte swap instructions
0xdc 0x0 0x40 0 dst = htobe64(dst) Byte swap instructions
0xdd any 0x00 any if dst s<= src goto +offset Jump instructions
0xde any 0x00 any if (s32)dst s<= (s32)src goto +offset Jump instructions
Normative References Guidelines for Writing an IANA Considerations Section in RFCs