eBPF Instruction Set Specification, v1.0
draft-thaler-bpf-isa-00
The information below is for an old version of the document.
| Document | Type |
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|
|---|---|---|---|
| Author | Dave Thaler | ||
| Last updated | 2023-03-13 | ||
| Replaced by | draft-ietf-bpf-isa, draft-ietf-bpf-isa | ||
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draft-thaler-bpf-isa-00
Network Working Group D. Thaler, Ed.
Internet-Draft Microsoft
Intended status: Standards Track 13 March 2023
Expires: 14 September 2023
eBPF Instruction Set Specification, v1.0
draft-thaler-bpf-isa-00
Abstract
This document specifies version 1.0 of the eBPF instruction set.
The eBPF instruction set consists of eleven 64 bit registers, a
program counter, and an implementation-specific amount (e.g., 512
bytes) of stack space.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
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and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 14 September 2023.
Copyright Notice
Copyright (c) 2023 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
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Table of Contents
1. Documentation conventions . . . . . . . . . . . . . . . . . . 2
2. Registers and calling convention . . . . . . . . . . . . . . 2
3. Instruction encoding . . . . . . . . . . . . . . . . . . . . 3
3.1. Instruction classes . . . . . . . . . . . . . . . . . . . 4
4. Arithmetic and jump instructions . . . . . . . . . . . . . . 5
4.1. Arithmetic instructions . . . . . . . . . . . . . . . . . 6
4.1.1. Byte swap instructions . . . . . . . . . . . . . . . 8
4.2. Jump instructions . . . . . . . . . . . . . . . . . . . . 9
4.2.1. Platform-agnostic helper functions . . . . . . . . . 11
4.2.2. Platform-specific helper functions . . . . . . . . . 11
4.2.3. BPF-local functions . . . . . . . . . . . . . . . . . 11
5. Load and store instructions . . . . . . . . . . . . . . . . . 11
5.1. Regular load and store operations . . . . . . . . . . . . 13
5.2. Atomic operations . . . . . . . . . . . . . . . . . . . . 13
5.3. 64-bit immediate instructions . . . . . . . . . . . . . . 15
5.3.1. Map objects . . . . . . . . . . . . . . . . . . . . . 17
5.3.2. Variables . . . . . . . . . . . . . . . . . . . . . . 17
5.4. Legacy BPF Packet access instructions . . . . . . . . . . 17
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 17
7. Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 30
1. Documentation conventions
For brevity, this document uses the type notion "u64", "u32", etc.
to mean an unsigned integer whose width is the specified number of
bits, and "s32", etc. to mean a signed integer of the specified
number of bits.
2. Registers and calling convention
eBPF has 10 general purpose registers and a read-only frame pointer
register, all of which are 64-bits wide.
The eBPF calling convention is defined as:
* R0: return value from function calls, and exit value for eBPF
programs
* R1 - R5: arguments for function calls
* R6 - R9: callee saved registers that function calls will preserve
* R10: read-only frame pointer to access stack
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Registers R0 - R5 are caller-saved registers, meaning the BPF program
needs to either spill them to the BPF stack or move them to callee
saved registers if these arguments are to be reused across multiple
function calls. Spilling means that the value in the register is
moved to the BPF stack. The reverse operation of moving the variable
from the BPF stack to the register is called filling. The reason for
spilling/filling is due to the limited number of registers.
Upon entering execution of an eBPF program, registers R1 - R5
initially can contain the input arguments for the program (similar to
the argc/argv pair for a typical C program). The actual number of
registers used, and their meaning, is defined by the program type;
for example, a networking program might have an argument that
includes network packet data and/or metadata.
3. Instruction encoding
An eBPF program is a sequence of instructions.
eBPF 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 (Section 5.3) reuse this
field for other purposes)
*dst_reg* destination register number (0-10)
*opcode* operation to perform
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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 must be set to zero.
As discussed below in 64-bit immediate instructions (Section 5.3), 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.
3.1. Instruction classes
The encoding of the 'opcode' field varies and can be determined from
the three least significant bits (LSB) of the 'opcode' field which
holds the "instruction class", as follows:
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+===========+=======+====================+==========================+
| class | value | description | reference |
+===========+=======+====================+==========================+
| BPF_LD | 0x00 | non-standard | Load and store |
| | | load operations | instructions (Section 5) |
+-----------+-------+--------------------+--------------------------+
| BPF_LDX | 0x01 | load into | Load and store |
| | | register | instructions (Section 5) |
| | | operations | |
+-----------+-------+--------------------+--------------------------+
| BPF_ST | 0x02 | store from | Load and store |
| | | immediate | instructions (Section 5) |
| | | operations | |
+-----------+-------+--------------------+--------------------------+
| BPF_STX | 0x03 | store from | Load and store |
| | | register | instructions (Section 5) |
| | | operations | |
+-----------+-------+--------------------+--------------------------+
| BPF_ALU | 0x04 | 32-bit | Arithmetic and jump |
| | | arithmetic | instructions (Section 4) |
| | | operations | |
+-----------+-------+--------------------+--------------------------+
| BPF_JMP | 0x05 | 64-bit jump | Arithmetic and jump |
| | | operations | instructions (Section 4) |
+-----------+-------+--------------------+--------------------------+
| BPF_JMP32 | 0x06 | 32-bit jump | Arithmetic and jump |
| | | operations | instructions (Section 4) |
+-----------+-------+--------------------+--------------------------+
| BPF_ALU64 | 0x07 | 64-bit | Arithmetic and jump |
| | | arithmetic | instructions (Section 4) |
| | | operations | |
+-----------+-------+--------------------+--------------------------+
Table 1
4. 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 |
+--------------+--------+-------------------+
Table 2
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*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 |
+--------+-------+------------------------------------------------+
Table 3
*instruction class* the instruction class (see Instruction classes
(Section 3.1))
4.1. Arithmetic instructions
Instruction class BPF_ALU uses 32-bit wide operands (zeroing the
upper 32 bits of the destination register) 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.
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+==========+=======+======================================+
| code | value | description |
+==========+=======+======================================+
| BPF_ADD | 0x00 | dst += src |
+----------+-------+--------------------------------------+
| BPF_SUB | 0x10 | dst -= src |
+----------+-------+--------------------------------------+
| BPF_MUL | 0x20 | dst *= src |
+----------+-------+--------------------------------------+
| BPF_DIV | 0x30 | dst = (src != 0) ? (dst / src) : 0 |
+----------+-------+--------------------------------------+
| BPF_OR | 0x40 | dst |= src |
+----------+-------+--------------------------------------+
| BPF_AND | 0x50 | dst &= src |
+----------+-------+--------------------------------------+
| BPF_LSH | 0x60 | dst <<= src |
+----------+-------+--------------------------------------+
| BPF_RSH | 0x70 | dst >>= src |
+----------+-------+--------------------------------------+
| BPF_NEG | 0x80 | dst = ~src |
+----------+-------+--------------------------------------+
| BPF_MOD | 0x90 | dst = (src != 0) ? (dst % src) : dst |
+----------+-------+--------------------------------------+
| BPF_XOR | 0xa0 | dst ^= src |
+----------+-------+--------------------------------------+
| BPF_MOV | 0xb0 | dst = src |
+----------+-------+--------------------------------------+
| BPF_ARSH | 0xc0 | sign extending shift right |
+----------+-------+--------------------------------------+
| BPF_END | 0xd0 | byte swap operations (see Byte swap |
| | | instructions (Section 4.1.1) below) |
+----------+-------+--------------------------------------+
Table 4
Underflow and overflow are allowed during arithmetic operations,
meaning the 64-bit or 32-bit value will wrap. If eBPF 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.
Examples:
BPF_ADD | BPF_X | BPF_ALU (0x0c) means:
dst = (u32) ((u32) dst + (u32) src)
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where '(u32)' indicates that the upper 32 bits are zeroed.
BPF_ADD | BPF_X | BPF_ALU64 (0x0f) means:
dst = dst + src
BPF_XOR | BPF_K | BPF_ALU (0xa4) means:
dst = (u32) dst ^ (u32) imm32
BPF_XOR | BPF_K | BPF_ALU64 (0xa7) means:
dst = dst ^ imm32
Also note that the division and modulo operations are unsigned.
Thus, for BPF_ALU, 'imm' is first interpreted as an unsigned 32-bit
value, whereas for BPF_ALU64, 'imm' is first sign extended to 64 bits
and the result interpreted as an unsigned 64-bit value. There are no
instructions for signed division or modulo.
4.1.1. Byte swap instructions
The byte swap instructions use an instruction class of BPF_ALU 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.
Byte swap instructions use the 1-bit 'source' field in the 'opcode'
field as follows. Instead of indicating the source operator, it is
instead used to select what byte order the operation converts from or
to:
+===========+=======+===========================+
| source | value | description |
+===========+=======+===========================+
| BPF_TO_LE | 0x00 | convert between host byte |
| | | order and little endian |
+-----------+-------+---------------------------+
| BPF_TO_BE | 0x08 | convert between host byte |
| | | order and big endian |
+-----------+-------+---------------------------+
Table 5
The 'imm' field encodes the width of the swap operations. The
following widths are supported: 16, 32 and 64. The following table
summarizes the resulting possibilities:
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+=====================+========+=====+==========+==============+
| opcode construction | opcode | imm | mnemonic | pseudocode |
+=====================+========+=====+==========+==============+
| BPF_END | | 0xd4 | 16 | le16 dst | dst = |
| BPF_TO_LE | BPF_ALU | | | | htole16(dst) |
+---------------------+--------+-----+----------+--------------+
| BPF_END | | 0xd4 | 32 | le32 dst | dst = |
| BPF_TO_LE | BPF_ALU | | | | htole32(dst) |
+---------------------+--------+-----+----------+--------------+
| BPF_END | | 0xd4 | 64 | le64 dst | dst = |
| BPF_TO_LE | BPF_ALU | | | | htole64(dst) |
+---------------------+--------+-----+----------+--------------+
| BPF_END | | 0xdc | 16 | be16 dst | dst = |
| BPF_TO_BE | BPF_ALU | | | | htobe16(dst) |
+---------------------+--------+-----+----------+--------------+
| BPF_END | | 0xdc | 32 | be32 dst | dst = |
| BPF_TO_BE | BPF_ALU | | | | htobe32(dst) |
+---------------------+--------+-----+----------+--------------+
| BPF_END | | 0xdc | 64 | be64 dst | dst = |
| BPF_TO_BE | BPF_ALU | | | | htobe64(dst) |
+---------------------+--------+-----+----------+--------------+
Table 6
where
* mnenomic indicates a short form that might be displayed by some
tools such as disassemblers
* 'htoleNN()' indicates converting a NN-bit value from host byte
order to little-endian byte order
* 'htobeNN()' indicates converting a NN-bit value from host byte
order to big-endian byte order
4.2. Jump instructions
Instruction class BPF_JMP32 uses 32-bit wide operands while BPF_JMP
uses 64-bit wide operands for otherwise identical operations.
The 4-bit 'code' field encodes the operation as below, where PC is
the program counter:
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+==========+=======+=====+===================+===================+
| code | value | src | description | notes |
+==========+=======+=====+===================+===================+
| BPF_JA | 0x0 | 0x0 | PC += offset | BPF_JMP only |
+----------+-------+-----+-------------------+-------------------+
| BPF_JEQ | 0x1 | any | PC += offset if | |
| | | | dst == src | |
+----------+-------+-----+-------------------+-------------------+
| BPF_JGT | 0x2 | any | PC += offset if | unsigned |
| | | | dst > src | |
+----------+-------+-----+-------------------+-------------------+
| BPF_JGE | 0x3 | any | PC += offset if | unsigned |
| | | | dst >= src | |
+----------+-------+-----+-------------------+-------------------+
| 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 | signed |
| | | | dst > src | |
+----------+-------+-----+-------------------+-------------------+
| BPF_JSGE | 0x7 | any | PC += offset if | signed |
| | | | dst >= src | |
+----------+-------+-----+-------------------+-------------------+
| BPF_CALL | 0x8 | 0x0 | call platform- | see |
| | | | agnostic helper | Platform-agnostic |
| | | | function imm | helper functions |
| | | | | (Section 4.2.1) |
+----------+-------+-----+-------------------+-------------------+
| BPF_CALL | 0x8 | 0x1 | call PC += offset | see BPF-local |
| | | | | functions |
| | | | | (Section 4.2.3) |
+----------+-------+-----+-------------------+-------------------+
| BPF_CALL | 0x8 | 0x2 | call platform- | see |
| | | | specific helper | Platform-specific |
| | | | function imm | helper functions |
| | | | | (Section 4.2.2) |
+----------+-------+-----+-------------------+-------------------+
| BPF_EXIT | 0x9 | 0x0 | return | BPF_JMP only |
+----------+-------+-----+-------------------+-------------------+
| BPF_JLT | 0xa | any | PC += offset if | unsigned |
| | | | dst < src | |
+----------+-------+-----+-------------------+-------------------+
| BPF_JLE | 0xb | any | PC += offset if | unsigned |
| | | | dst <= src | |
+----------+-------+-----+-------------------+-------------------+
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| BPF_JSLT | 0xc | any | PC += offset if | signed |
| | | | dst < src | |
+----------+-------+-----+-------------------+-------------------+
| BPF_JSLE | 0xd | any | PC += offset if | signed |
| | | | dst <= src | |
+----------+-------+-----+-------------------+-------------------+
Table 7
Example:
BPF_JSGE | BPF_X | BPF_JMP32 (0x7e) means:
if (s32)dst s>= (s32)src goto +offset
where 's>=' indicates a signed '>=' comparison.
4.2.1. Platform-agnostic helper functions
Platform-agnostic helper functions are a concept whereby BPF programs
can call into a set of function calls exposed by the runtime. Each
helper function is identified by an integer used in a BPF_CALL
instruction. The available platform-agnostic helper functions may
differ for each program type, but integer values are unique across
all program types.
4.2.2. Platform-specific helper functions
Platform-specific helper functions are helper functions that are
unique to a particular platform. They use a separate integer
numbering space from platform-agnostic helper functions, but
otherwise the same considerations apply. Platforms are not required
to implement any platform-specific functions.
4.2.3. BPF-local functions
BPF-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. A BPF_EXIT within the BPF-local function will
return to the caller.
5. Load and store instructions
For load and store instructions (BPF_LD, BPF_LDX, BPF_ST, and
BPF_STX), the 8-bit 'opcode' field is divided as:
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+==============+========+===================+
| 3 bits (MSB) | 2 bits | 3 bits (LSB) |
+==============+========+===================+
| mode | size | instruction class |
+--------------+--------+-------------------+
Table 8
mode one of:
+============+=======+==================+=====================+
| mode | value | description | reference |
| modifier | | | |
+============+=======+==================+=====================+
| BPF_IMM | 0x00 | 64-bit immediate | 64-bit immediate |
| | | instructions | instructions |
| | | | (Section 5.3) |
+------------+-------+------------------+---------------------+
| BPF_ABS | 0x20 | legacy BPF | Legacy BPF Packet |
| | | packet access | access instructions |
| | | (absolute) | (Section 5.4) |
+------------+-------+------------------+---------------------+
| BPF_IND | 0x40 | legacy BPF | Legacy BPF Packet |
| | | packet access | access instructions |
| | | (indirect) | (Section 5.4) |
+------------+-------+------------------+---------------------+
| BPF_MEM | 0x60 | regular load and | Regular load and |
| | | store operations | store operations |
| | | | (Section 5.1) |
+------------+-------+------------------+---------------------+
| BPF_ATOMIC | 0xc0 | atomic | Atomic operations |
| | | operations | (Section 5.2) |
+------------+-------+------------------+---------------------+
Table 9
size one of:
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+===============+=======+=======================+
| 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) |
+---------------+-------+-----------------------+
Table 10
instruction class the instruction class (see Instruction classes
(Section 3.1))
5.1. Regular load and store operations
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 = *(size *) (src + offset)
where size is one of: BPF_B, BPF_H, BPF_W, or BPF_DW.
5.2. Atomic operations
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 eBPF programs or means outside of this specification.
All atomic operations supported by eBPF are encoded as store
operations that use the BPF_ATOMIC mode modifier as follows:
* BPF_ATOMIC | BPF_W | BPF_STX (0xc3) for 32-bit operations
* BPF_ATOMIC | BPF_DW | BPF_STX (0xdb) for 64-bit operations
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Note that 8-bit (BPF_B) and 16-bit (BPF_H) wide atomic operations are
not supported, nor is BPF_ATOMIC | <size> | BPF_ST.
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 |
+---------+-------+-------------+
Table 11
BPF_ATOMIC | BPF_W | BPF_STX (0xc3) with 'imm' = BPF_ADD means:
*(u32 *)(dst + offset) += src
BPF_ATOMIC | BPF_DW | BPF_STX (0xdb) with 'imm' = BPF ADD means:
*(u64 *)(dst + offset) += src
In addition to the simple atomic operations above, 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 |
+-------------+------------------+-----------------------------+
Table 12
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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.
5.3. 64-bit immediate instructions
Instructions with the BPF_IMM 'mode' modifier use the wide
instruction encoding defined in Instruction encoding (Section 3), and
use the 'src' field of the basic instruction to hold an opcode
subtype.
The following instructions are defined, and use additional concepts
defined below:
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+==============+======+===+======================+========+=======+
| opcode |opcode|src| pseudocode |imm type|dst |
| construction | | | | |type |
+==============+======+===+======================+========+=======+
| BPF_IMM | |0x18 |0x0| dst = imm64 |integer |integer|
| BPF_DW | | | | | | |
| BPF_LD | | | | | |
+--------------+------+---+----------------------+--------+-------+
| BPF_IMM | |0x18 |0x1| dst = map_by_fd(imm) |map fd |map |
| BPF_DW | | | | | | |
| BPF_LD | | | | | |
+--------------+------+---+----------------------+--------+-------+
| BPF_IMM | |0x18 |0x2| dst = |map fd |data |
| BPF_DW | | | | mva(map_by_fd(imm)) | |pointer|
| BPF_LD | | | + next_imm | | |
+--------------+------+---+----------------------+--------+-------+
| BPF_IMM | |0x18 |0x3| dst = |variable|data |
| BPF_DW | | | | variable_addr(imm) |id |pointer|
| BPF_LD | | | | | |
+--------------+------+---+----------------------+--------+-------+
| BPF_IMM | |0x18 |0x4| dst = code_addr(imm) |integer |code |
| BPF_DW | | | | | |pointer|
| BPF_LD | | | | | |
+--------------+------+---+----------------------+--------+-------+
| BPF_IMM | |0x18 |0x5| dst = |map |map |
| BPF_DW | | | | map_by_idx(imm) |index | |
| BPF_LD | | | | | |
+--------------+------+---+----------------------+--------+-------+
| BPF_IMM | |0x18 |0x6| dst = |map |data |
| BPF_DW | | | | mva(map_by_idx(imm)) |index |pointer|
| BPF_LD | | | + next_imm | | |
+--------------+------+---+----------------------+--------+-------+
Table 13
where
* map_by_fd(fd) means to convert a 32-bit POSIX file descriptor into
an address of a map object (see Map objects (Section 5.3.1))
* map_by_index(index) means to convert a 32-bit index into an
address of a map object
* mva(map) gets the address of the first value in a given map object
* variable_addr(id) gets the address of a variable (see Variables
(Section 5.3.2)) with a given id
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* code_addr(offset) gets the address of the instruction at a
specified relative offset in units of 64-bit blocks
* the 'imm type' can be used by disassemblers for display
* the 'dst type' can be used for verification and JIT compilation
purposes
5.3.1. Map objects
Maps are shared memory regions accessible by eBPF programs on some
platforms, where we use the term "map object" to refer to an object
containing the data and metadata (e.g., size) about the memory
region. 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 'mva(map)' is currently only defined for maps that do have a
single contiguous memory region. Support for maps is optional.
Each map object can have a POSIX file descriptor (fd) if supported by
the platform, where 'map_by_fd(fd)' means to get the map with the
specified file descriptor. Each eBPF program can also be defined to
use a set of maps associated with the program at load time, and
'map_by_index(index)' means to get the map with the given index in
the set associated with the eBPF program containing the instruction.
5.3.2. Variables
Variables are memory regions, identified by integer ids, accessible
by eBPF programs on some platforms. The 'variable_addr(id)'
operation means to get the address of the memory region identified by
the given id. Support for such variables is optional.
5.4. Legacy BPF Packet access instructions
eBPF 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.
6. Acknowledgements
This draft was generated from instruction-set.rst in the Linux kernel
repository, to which a number of other individuals have contributed
over time, including Akhil Raj, Christoph Hellwig, Jose E. Marchesi,
Kosuke Fujimoto, Shahab Vahedi, Tiezhu Yang, and Zheng Yejian, with
review and suggestions by many others including Alan Jowett, Alexei
Starovoitov, Andrii Nakryiko, Daniel Borkmann, David Vernet, Jim
Harris, Quentin Monnet, Song Liu, Shung-Hsi Yu, Stanislav Fomichev,
and Yonghong Song.
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7. Appendix
For reference, the following table lists opcodes in order by value.
+========+===+======+==========================+===================+
| opcode |src| imm |description | reference |
+========+===+======+==========================+===================+
| 0x00 |0x0| any |(additional immediate | 64-bit immediate |
| | | |value) | instructions |
| | | | | (Section 5.3) |
+--------+---+------+--------------------------+-------------------+
| 0x04 |0x0| any |dst = (u32)((u32)dst + | Arithmetic |
| | | |(u32)imm) | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x05 |0x0| 0x00 |goto +offset | Jump instructions |
| | | | | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x07 |0x0| any |dst += imm | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x0c |any| 0x00 |dst = (u32)((u32)dst + | Arithmetic |
| | | |(u32)src) | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x0f |any| 0x00 |dst += src | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x14 |0x0| any |dst = (u32)((u32)dst - | Arithmetic |
| | | |(u32)imm) | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x15 |0x0| any |if dst == imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x16 |0x0| any |if (u32)dst == imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x17 |0x0| any |dst -= imm | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x18 |0x0| any |dst = imm64 | 64-bit immediate |
| | | | | instructions |
| | | | | (Section 5.3) |
+--------+---+------+--------------------------+-------------------+
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| 0x18 |0x1| any |dst = map_by_fd(imm) | 64-bit immediate |
| | | | | instructions |
| | | | | (Section 5.3) |
+--------+---+------+--------------------------+-------------------+
| 0x18 |0x2| any |dst = | 64-bit immediate |
| | | |mva(map_by_fd(imm)) + | instructions |
| | | |next_imm | (Section 5.3) |
+--------+---+------+--------------------------+-------------------+
| 0x18 |0x3| any |dst = variable_addr(imm) | 64-bit immediate |
| | | | | instructions |
| | | | | (Section 5.3) |
+--------+---+------+--------------------------+-------------------+
| 0x18 |0x4| any |dst = code_addr(imm) | 64-bit immediate |
| | | | | instructions |
| | | | | (Section 5.3) |
+--------+---+------+--------------------------+-------------------+
| 0x18 |0x5| any |dst = map_by_idx(imm) | 64-bit immediate |
| | | | | instructions |
| | | | | (Section 5.3) |
+--------+---+------+--------------------------+-------------------+
| 0x18 |0x6| any |dst = | 64-bit immediate |
| | | |mva(map_by_idx(imm)) + | instructions |
| | | |next_imm | (Section 5.3) |
+--------+---+------+--------------------------+-------------------+
| 0x1c |any| 0x00 |dst = (u32)((u32)dst - | Arithmetic |
| | | |(u32)src) | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x1d |any| 0x00 |if dst == src goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x1e |any| 0x00 |if (u32)dst == (u32)src | Jump instructions |
| | | |goto +offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x1f |any| 0x00 |dst -= src | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x20 |any| any |(deprecated, | Legacy BPF Packet |
| | | |implementation-specific) | access |
| | | | | instructions |
| | | | | (Section 5.4) |
+--------+---+------+--------------------------+-------------------+
| 0x24 |0x0| any |dst = (u32)(dst * imm) | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x25 |0x0| any |if dst > imm goto | Jump instructions |
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| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x26 |0x0| any |if (u32)dst > imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x27 |0x0| any |dst *= imm | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x28 |any| any |(deprecated, | Legacy BPF Packet |
| | | |implementation-specific) | access |
| | | | | instructions |
| | | | | (Section 5.4) |
+--------+---+------+--------------------------+-------------------+
| 0x2c |any| 0x00 |dst = (u32)(dst * src) | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x2d |any| 0x00 |if dst > src goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x2e |any| 0x00 |if (u32)dst > (u32)src | Jump instructions |
| | | |goto +offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x2f |any| 0x00 |dst *= src | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x30 |any| any |(deprecated, | Legacy BPF Packet |
| | | |implementation-specific) | access |
| | | | | instructions |
| | | | | (Section 5.4) |
+--------+---+------+--------------------------+-------------------+
| 0x34 |0x0| any |dst = (u32)((imm != 0) ? | Arithmetic |
| | | |(dst / imm) : 0) | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x35 |0x0| any |if dst >= imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x36 |0x0| any |if (u32)dst >= imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x37 |0x0| any |dst = (imm != 0) ? (dst | Arithmetic |
| | | |/ imm) : 0 | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x38 |any| any |(deprecated, | Legacy BPF Packet |
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| | | |implementation-specific) | access |
| | | | | instructions |
| | | | | (Section 5.4) |
+--------+---+------+--------------------------+-------------------+
| 0x3c |any| 0x00 |dst = (u32)((imm != 0) ? | Arithmetic |
| | | |(dst / src) : 0) | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x3d |any| 0x00 |if dst >= src goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x3e |any| 0x00 |if (u32)dst >= (u32)src | Jump instructions |
| | | |goto +offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x3f |any| 0x00 |dst = (src !+ 0) ? (dst | Arithmetic |
| | | |/ src) : 0 | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x40 |any| any |(deprecated, | Legacy BPF Packet |
| | | |implementation-specific) | access |
| | | | | instructions |
| | | | | (Section 5.4) |
+--------+---+------+--------------------------+-------------------+
| 0x44 |0x0| any |dst = (u32)(dst | imm) | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x45 |0x0| any |if dst & imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x46 |0x0| any |if (u32)dst & imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x47 |0x0| any |dst |= imm | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x48 |any| any |(deprecated, | Legacy BPF Packet |
| | | |implementation-specific) | access |
| | | | | instructions |
| | | | | (Section 5.4) |
+--------+---+------+--------------------------+-------------------+
| 0x4c |any| 0x00 |dst = (u32)(dst | src) | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x4d |any| 0x00 |if dst & src goto | Jump instructions |
| | | |+offset | (Section 4.2) |
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+--------+---+------+--------------------------+-------------------+
| 0x4e |any| 0x00 |if (u32)dst & (u32)src | Jump instructions |
| | | |goto +offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x4f |any| 0x00 |dst |= src | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x50 |any| any |(deprecated, | Legacy BPF Packet |
| | | |implementation-specific) | access |
| | | | | instructions |
| | | | | (Section 5.4) |
+--------+---+------+--------------------------+-------------------+
| 0x54 |0x0| any |dst = (u32)(dst & imm) | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x55 |0x0| any |if dst != imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x56 |0x0| any |if (u32)dst != imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x57 |0x0| any |dst &= imm | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x58 |any| any |(deprecated, | Legacy BPF Packet |
| | | |implementation-specific) | access |
| | | | | instructions |
| | | | | (Section 5.4) |
+--------+---+------+--------------------------+-------------------+
| 0x5c |any| 0x00 |dst = (u32)(dst & src) | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x5d |any| 0x00 |if dst != src goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x5e |any| 0x00 |if (u32)dst != (u32)src | Jump instructions |
| | | |goto +offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x5f |any| 0x00 |dst &= src | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x61 |any| 0x00 |dst = *(u32 *)(src + | Load and store |
| | | |offset) | instructions |
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| | | | | (Section 5) |
+--------+---+------+--------------------------+-------------------+
| 0x62 |0x0| any |*(u32 *)(dst + offset) = | Load and store |
| | | |imm | instructions |
| | | | | (Section 5) |
+--------+---+------+--------------------------+-------------------+
| 0x63 |any| 0x00 |*(u32 *)(dst + offset) = | Load and store |
| | | |src | instructions |
| | | | | (Section 5) |
+--------+---+------+--------------------------+-------------------+
| 0x64 |0x0| any |dst = (u32)(dst << imm) | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x65 |0x0| any |if dst s> imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x66 |0x0| any |if (s32)dst s> (s32)imm | Jump instructions |
| | | |goto +offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x67 |0x0| any |dst <<= imm | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x69 |any| 0x00 |dst = *(u16 *)(src + | Load and store |
| | | |offset) | instructions |
| | | | | (Section 5) |
+--------+---+------+--------------------------+-------------------+
| 0x6a |0x0| any |*(u16 *)(dst + offset) = | Load and store |
| | | |imm | instructions |
| | | | | (Section 5) |
+--------+---+------+--------------------------+-------------------+
| 0x6b |any| 0x00 |*(u16 *)(dst + offset) = | Load and store |
| | | |src | instructions |
| | | | | (Section 5) |
+--------+---+------+--------------------------+-------------------+
| 0x6c |any| 0x00 |dst = (u32)(dst << src) | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x6d |any| 0x00 |if dst s> src goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x6e |any| 0x00 |if (s32)dst s> (s32)src | Jump instructions |
| | | |goto +offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x6f |any| 0x00 |dst <<= src | Arithmetic |
| | | | | instructions |
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| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x71 |any| 0x00 |dst = *(u8 *)(src + | Load and store |
| | | |offset) | instructions |
| | | | | (Section 5) |
+--------+---+------+--------------------------+-------------------+
| 0x72 |0x0| any |*(u8 *)(dst + offset) = | Load and store |
| | | |imm | instructions |
| | | | | (Section 5) |
+--------+---+------+--------------------------+-------------------+
| 0x73 |any| 0x00 |*(u8 *)(dst + offset) = | Load and store |
| | | |src | instructions |
| | | | | (Section 5) |
+--------+---+------+--------------------------+-------------------+
| 0x74 |0x0| any |dst = (u32)(dst >> imm) | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x75 |0x0| any |if dst s>= imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x76 |0x0| any |if (s32)dst s>= (s32)imm | Jump instructions |
| | | |goto +offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x77 |0x0| any |dst >>= imm | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x79 |any| 0x00 |dst = *(u64 *)(src + | Load and store |
| | | |offset) | instructions |
| | | | | (Section 5) |
+--------+---+------+--------------------------+-------------------+
| 0x7a |0x0| any |*(u64 *)(dst + offset) = | Load and store |
| | | |imm | instructions |
| | | | | (Section 5) |
+--------+---+------+--------------------------+-------------------+
| 0x7b |any| 0x00 |*(u64 *)(dst + offset) = | Load and store |
| | | |src | instructions |
| | | | | (Section 5) |
+--------+---+------+--------------------------+-------------------+
| 0x7c |any| 0x00 |dst = (u32)(dst >> src) | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x7d |any| 0x00 |if dst s>= src goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x7e |any| 0x00 |if (s32)dst s>= (s32)src | Jump instructions |
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| | | |goto +offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x7f |any| 0x00 |dst >>= src | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x84 |0x0| 0x00 |dst = (u32)-dst | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x85 |0x0| any |call platform-agnostic | Platform-agnostic |
| | | |helper function imm | helper functions |
| | | | | (Section 4.2.1) |
+--------+---+------+--------------------------+-------------------+
| 0x85 |0x1| any |call PC += offset | BPF-local |
| | | | | functions |
| | | | | (Section 4.2.3) |
+--------+---+------+--------------------------+-------------------+
| 0x85 |0x2| any |call platform-specific | Platform-specific |
| | | |helper function imm | helper functions |
| | | | | (Section 4.2.2) |
+--------+---+------+--------------------------+-------------------+
| 0x87 |0x0| 0x00 |dst = -dst | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x94 |0x0| any |dst = (u32)((imm != 0) ? | Arithmetic |
| | | |(dst % imm) : dst) | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x95 |0x0| 0x00 |return | Jump instructions |
| | | | | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0x97 |0x0| any |dst = (imm != 0) ? (dst | Arithmetic |
| | | |% imm) : dst | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x9c |any| 0x00 |dst = (u32)((src != 0) ? | Arithmetic |
| | | |(dst % src) : dst) | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0x9f |any| 0x00 |dst = (src != 0) ? (dst | Arithmetic |
| | | |% src) : dst | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0xa4 |0x0| any |dst = (u32)(dst ^ imm) | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
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+--------+---+------+--------------------------+-------------------+
| 0xa5 |0x0| any |if dst < imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0xa6 |0x0| any |if (u32)dst < imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0xa7 |0x0| any |dst ^= imm | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0xac |any| 0x00 |dst = (u32)(dst ^ src) | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0xad |any| 0x00 |if dst < src goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0xae |any| 0x00 |if (u32)dst < (u32)src | Jump instructions |
| | | |goto +offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0xaf |any| 0x00 |dst ^= src | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0xb4 |0x0| any |dst = (u32) imm | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0xb5 |0x0| any |if dst <= imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0xa6 |0x0| any |if (u32)dst <= imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0xb7 |0x0| any |dst = imm | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0xbc |any| 0x00 |dst = (u32) src | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0xbd |any| 0x00 |if dst <= src goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0xbe |any| 0x00 |if (u32)dst <= (u32)src | Jump instructions |
| | | |goto +offset | (Section 4.2) |
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Internet-Draft eBPF ISA March 2023
+--------+---+------+--------------------------+-------------------+
| 0xbf |any| 0x00 |dst = src | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0xc3 |any| 0x00 |lock *(u32 *)(dst + | Atomic operations |
| | | |offset) += src | (Section 5.2) |
+--------+---+------+--------------------------+-------------------+
| 0xc3 |any| 0x01 |lock: | Atomic operations |
| | | | | (Section 5.2) |
| | | | *(u32 *)(dst + offset) += src| |
| | | | src = *(u32 *)(dst + offset)| |
+--------+---+------+--------------------------+-------------------+
| 0xc3 |any| 0x40 |*(u32 *)(dst + | Atomic operations |
| | | |offset) |= src | (Section 5.2) |
+--------+---+------+--------------------------+-------------------+
| 0xc3 |any| 0x41 |lock: | Atomic operations |
| | | | | (Section 5.2) |
| | | | *(u32 *)(dst + offset) |= src| |
| | | | src = *(u32 *)(dst + offset)| |
+--------+---+------+--------------------------+-------------------+
| 0xc3 |any| 0x50 |*(u32 *)(dst + offset) | Atomic operations |
| | | |&= src | (Section 5.2) |
+--------+---+------+--------------------------+-------------------+
| 0xc3 |any| 0x51 |lock: | Atomic operations |
| | | | | (Section 5.2) |
| | | | *(u32 *)(dst + offset) &= src| |
| | | | src = *(u32 *)(dst + offset)| |
+--------+---+------+--------------------------+-------------------+
| 0xc3 |any| 0xa0 |*(u32 *)(dst + offset) | Atomic operations |
| | | |^= src | (Section 5.2) |
+--------+---+------+--------------------------+-------------------+
| 0xc3 |any| 0xa1 |lock: | Atomic operations |
| | | | | (Section 5.2) |
| | | | *(u32 *)(dst + offset) ^= src| |
| | | | src = *(u32 *)(dst + offset)| |
+--------+---+------+--------------------------+-------------------+
| 0xc3 |any| 0xe1 |lock: | Atomic operations |
| | | | | (Section 5.2) |
| | | | temp = *(u32 *)(dst + offset)| |
| | | | *(u32 *)(dst + offset) = src| |
| | | | src = temp | |
+--------+---+------+--------------------------+-------------------+
| 0xc3 |any| 0xf1 |lock: | Atomic operations |
| | | | | (Section 5.2) |
| | | | temp = *(u32 *)(dst + offset)| |
| | | | if *(u32)(dst + offset) == R0| |
| | | | *(u32)(dst + offset) = src| |
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| | | | R0 = temp | |
+--------+---+------+--------------------------+-------------------+
| 0xc4 |0x0| any |dst = (u32)(dst s>> imm) | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0xc5 |0x0| any |if dst s< imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0xc6 |0x0| any |if (s32)dst s< (s32)imm | Jump instructions |
| | | |goto +offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0xc7 |0x0| any |dst s>>= imm | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0xcc |any| 0x00 |dst = (u32)(dst s>> src) | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0xcd |any| 0x00 |if dst s< src goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0xce |any| 0x00 |if (s32)dst s< (s32)src | Jump instructions |
| | | |goto +offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0xcf |any| 0x00 |dst s>>= src | Arithmetic |
| | | | | instructions |
| | | | | (Section 4.1) |
+--------+---+------+--------------------------+-------------------+
| 0xd4 |0x0| 0x10 |dst = htole16(dst) | Byte swap |
| | | | | instructions |
| | | | | (Section 4.1.1) |
+--------+---+------+--------------------------+-------------------+
| 0xd4 |0x0| 0x20 |dst = htole32(dst) | Byte swap |
| | | | | instructions |
| | | | | (Section 4.1.1) |
+--------+---+------+--------------------------+-------------------+
| 0xd4 |0x0| 0x40 |dst = htole64(dst) | Byte swap |
| | | | | instructions |
| | | | | (Section 4.1.1) |
+--------+---+------+--------------------------+-------------------+
| 0xd5 |0x0| any |if dst s<= imm goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0xd6 |0x0| any |if (s32)dst s<= (s32)imm | Jump instructions |
| | | |goto +offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
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Internet-Draft eBPF ISA March 2023
| 0xdb |any| 0x00 |lock *(u64 *)(dst + | Atomic operations |
| | | |offset) += src | (Section 5.2) |
+--------+---+------+--------------------------+-------------------+
| 0xdb |any| 0x01 |lock: | Atomic operations |
| | | | | (Section 5.2) |
| | | | *(u64 *)(dst + offset) += src| |
| | | | src = *(u64 *)(dst + offset)| |
+--------+---+------+--------------------------+-------------------+
| 0xdb |any| 0x40 |*(u64 *)(dst + | Atomic operations |
| | | |offset) |= src | (Section 5.2) |
+--------+---+------+--------------------------+-------------------+
| 0xdb |any| 0x41 |lock: | Atomic operations |
| | | | | (Section 5.2) |
| | | | *(u64 *)(dst + offset) |= src| |
| | | | lock src = *(u64 *)(dst + offset)| |
+--------+---+------+--------------------------+-------------------+
| 0xdb |any| 0x50 |*(u64 *)(dst + offset) | Atomic operations |
| | | |&= src | (Section 5.2) |
+--------+---+------+--------------------------+-------------------+
| 0xdb |any| 0x51 |lock: | Atomic operations |
| | | | | (Section 5.2) |
| | | | *(u64 *)(dst + offset) &= src| |
| | | | src = *(u64 *)(dst + offset)| |
+--------+---+------+--------------------------+-------------------+
| 0xdb |any| 0xa0 |*(u64 *)(dst + offset) | Atomic operations |
| | | |^= src | (Section 5.2) |
+--------+---+------+--------------------------+-------------------+
| 0xdb |any| 0xa1 |lock: | Atomic operations |
| | | | | (Section 5.2) |
| | | | *(u64 *)(dst + offset) ^= src| |
| | | | src = *(u64 *)(dst + offset)| |
+--------+---+------+--------------------------+-------------------+
| 0xdb |any| 0xe1 |lock: | Atomic operations |
| | | | | (Section 5.2) |
| | | | temp = *(u64 *)(dst + offset)| |
| | | | *(u64 *)(dst + offset) = src| |
| | | | src = temp | |
+--------+---+------+--------------------------+-------------------+
| 0xdb |any| 0xf1 |lock: | Atomic operations |
| | | | | (Section 5.2) |
| | | | temp = *(u64 *)(dst + offset)| |
| | | | if *(u64)(dst + offset) == R0| |
| | | | *(u64)(dst + offset) = src| |
| | | | R0 = temp | |
+--------+---+------+--------------------------+-------------------+
| 0xdc |0x0| 0x10 |dst = htobe16(dst) | Byte swap |
| | | | | instructions |
| | | | | (Section 4.1.1) |
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Internet-Draft eBPF ISA March 2023
+--------+---+------+--------------------------+-------------------+
| 0xdc |0x0| 0x20 |dst = htobe32(dst) | Byte swap |
| | | | | instructions |
| | | | | (Section 4.1.1) |
+--------+---+------+--------------------------+-------------------+
| 0xdc |0x0| 0x40 |dst = htobe64(dst) | Byte swap |
| | | | | instructions |
| | | | | (Section 4.1.1) |
+--------+---+------+--------------------------+-------------------+
| 0xdd |any| 0x00 |if dst s<= src goto | Jump instructions |
| | | |+offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
| 0xde |any| 0x00 |if (s32)dst s<= (s32)src | Jump instructions |
| | | |goto +offset | (Section 4.2) |
+--------+---+------+--------------------------+-------------------+
Table 14
Author's Address
Dave Thaler (editor)
Microsoft
Redmond, WA 98052
United States of America
Email: dthaler@microsoft.com
Thaler Expires 14 September 2023 [Page 30]