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* Generate dictionary of all possible eBPF instructions Signed-off-by: Alan Jowett <[email protected]> * Update verifier Signed-off-by: Alan Jowett <[email protected]> --------- Signed-off-by: Alan Jowett <[email protected]> Co-authored-by: Alan Jowett <[email protected]>
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Submodule ebpf-verifier
updated
3 files
| +27 −1 | src/assertions.cpp | |
| +2 −0 | src/test/ebpf_yaml.cpp | |
| +540 −0 | test-data/jump.yaml |
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| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,147 @@ | ||
| # Copyright (c) uBPF contributors | ||
| # SPDX-License-Identifier: MIT | ||
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| # Generate a dictionary file of all legal BPF instructions, with immediate values and offsets set to zero. | ||
| # Each instruction is written to the output stream in the form of a quoted 8-byte sequence of hex, with each byte prefixed wit\x with no spaces. | ||
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| import struct | ||
| import disassembler | ||
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| Inst = struct.Struct("BBHI") | ||
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| CLASSES = { | ||
| 0: "ld", | ||
| 1: "ldx", | ||
| 2: "st", | ||
| 3: "stx", | ||
| 4: "alu", | ||
| 5: "jmp", | ||
| 6: "jmp32", | ||
| 7: "alu64", | ||
| } | ||
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| ALU_OPCODES = { | ||
| 0: 'add', | ||
| 1: 'sub', | ||
| 2: 'mul', | ||
| 3: 'div', | ||
| 4: 'or', | ||
| 5: 'and', | ||
| 6: 'lsh', | ||
| 7: 'rsh', | ||
| 8: 'neg', | ||
| 9: 'mod', | ||
| 10: 'xor', | ||
| 11: 'mov', | ||
| 12: 'arsh', | ||
| 13: '(endian)', | ||
| } | ||
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| JMP_OPCODES = { | ||
| 0: 'ja', | ||
| 1: 'jeq', | ||
| 2: 'jgt', | ||
| 3: 'jge', | ||
| 4: 'jset', | ||
| 5: 'jne', | ||
| 6: 'jsgt', | ||
| 7: 'jsge', | ||
| 8: 'call', | ||
| 9: 'exit', | ||
| 10: 'jlt', | ||
| 11: 'jle', | ||
| 12: 'jslt', | ||
| 13: 'jsle', | ||
| } | ||
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| MODES = { | ||
| 0: 'imm', | ||
| 1: 'abs', | ||
| 2: 'ind', | ||
| 3: 'mem', | ||
| 6: 'xadd', | ||
| } | ||
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| SIZES = { | ||
| 0: 'w', | ||
| 1: 'h', | ||
| 2: 'b', | ||
| 3: 'dw', | ||
| } | ||
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| # All opcodes have the similar format of: | ||
| # 0-2: class identifier | ||
| # 3-7: class specific opcode | ||
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| # For LD and store instructions: | ||
| # 3-4: size | ||
| # 5-7: mode | ||
| BPF_CLASS_LD = 0 | ||
| BPF_CLASS_LDX = 1 | ||
| BPF_CLASS_ST = 2 | ||
| BPF_CLASS_STX = 3 | ||
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| # For ALU and jump instructions: | ||
| # 3: Source (register or immediate) | ||
| # 4-7: ALU opcode | ||
| BPF_CLASS_ALU32 = 4 | ||
| BPF_CLASS_JMP = 5 | ||
| BPF_CLASS_JMP32 = 6 | ||
| BPF_CLASS_ALU = 7 | ||
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| BPF_ALU_NEG = 8 | ||
| BPF_ALU_END = 13 | ||
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| # Pack an instruction into a byte array | ||
| # The instruction is packed as follows: | ||
| # Byte: 0: opcode | ||
| # Byte: 1: source register and destination register | ||
| # Short: 2: offset | ||
| # Int: 4: immediate value | ||
| def gen_inst(source_register : int, dest_register : int, opcode : int, offset : int, immediate : int) -> bytes: | ||
| return Inst.pack(opcode, source_register << 4 | dest_register, offset, immediate) | ||
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| # Generate a load or store opcode | ||
| def gen_ld_st_opcode(op_class : int, size : int, mode : int) -> int: | ||
| return op_class << 3 | size << 1 | mode | ||
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| # Generate an ALU or JMPM opcode | ||
| def gen_alu_or_jump_opcode(op_class : int, source : int, opcode : int) -> int: | ||
| return op_class << 3 | source << 2 | opcode | ||
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| def encode_and_print_instruction(inst : bytes): | ||
| # Check for special case of BPF_LDDDW instruction which is two instructions | ||
| if inst[0] & 7 == 0: | ||
| inst = inst + b"\x00\x00\x00\x00\x00\x00\x00\x00" | ||
| mnemonic = disassembler.disassemble_one(inst, 0) | ||
| if "Warnings" in mnemonic[0]: | ||
| return | ||
| # If the mnemonic tuple contains more than one element, skip it | ||
| print(mnemonic[0], "=", end="") | ||
| print("\"", end="") | ||
| for byte in inst: | ||
| print("\\x{:02x}".format(byte), end="") | ||
| print("\"") | ||
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| # Generate all possible instructions | ||
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| # Load and store instructions | ||
| for op_class in range(4): | ||
| for size in range(4): | ||
| for mode in range(8): | ||
| opcode = gen_ld_st_opcode(op_class, size, mode) | ||
| for source_register in range(11): | ||
| for dest_register in range(11): | ||
| inst = gen_inst(source_register, dest_register, opcode, 0, 0) | ||
| encode_and_print_instruction(inst) | ||
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| # ALU and JMP instructions (range 4-7) | ||
| for op_class in range(4, 8): | ||
| for source in range(2): | ||
| for alu_op in range(14): | ||
| opcode = gen_alu_or_jump_opcode(op_class, source, alu_op) | ||
| for source_register in range(11): | ||
| for dest_register in range(11): | ||
| inst = gen_inst(source_register, dest_register, opcode, 0, 0) | ||
| encode_and_print_instruction(inst) | ||
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