RZ-ASM(1)

🌸 NAME 🌸

okay so, bestie, this is rz-asm — the rizin assembler and disassembler tool, and yes, this is the manual page for RZ_ASM(1). 💅

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✨ SYNOPSIS ✨

the whole vibe in one line, no cap:

rz-asm [-ABCdDeIEhjLpqrvxw] [-a arch] [-b bits] [-m plugin] [-c CPU]
       [-O file] [-o addr] [-@ addr] [-f file] [-F in:out] [-i len]
       [-k kernel] [-s syntax] [-l len]

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💖 DESCRIPTION 💖

okay so this command is part of the Rizin project. 🫶

This tool uses RzAsm to assemble and disassemble files or hexpair strings. It supports a large list of architectures which can be listed using the -L flag. ✨

🚩 flags, flags, flags 🚩

• -a arch — Set architecture to assemble/disassemble (see -L)
• -A — Show analysis information from given hexpairs
• -b bits — Set CPU register size (8, 16, 32, 64) (RZ_ASM_BITS)
• -B — Binary input/output (-l is mandatory for binary input)
• -c CPU — Select specific CPU (depends on the arch)
• -C — Output in C format
• -d, -D — Disassemble from hexpair bytes (-D show hexpairs)
• -e — Use big endian instead of little endian
• -I — Display lifted RzIL code (same input as in -d, IL is also validated)
• -E — Display ESIL expression (same input as in -d)
• -f file — Read data from file
• -F in:out — Specify input and/or output filters (att2intel, x86.pseudo, ...)
• -h, -hh — Show usage help message, hh for long
• -i len — Ignore N bytes of the input buffer
• -j — Output in JSON format
• -k kernel — Select operating system (linux, windows, darwin, ..)
• -l len — Input/Output length
• -L — List asm plugins: (a=asm, d=disasm, A=analyze, e=ESIL)
• -m plugin — List supported CPUs for the chosen plugin
• -o, -@ addr — Set start address for code (default 0)
• -O file — Output file name (rz-asm -Bf a.asm -O a)
• -p — Run SPP over input for assembly
• -q — Quiet mode
• -r — Output in rizin commands
• -s syntax — Select syntax (intel, att)
• -v — Show version information
• -x — Use hex dwords instead of hex pairs when assembling
• -w — Describe opcode

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🎀 Directives 🎀

these are the little dot-directives, and they are lowkey iconic:

• .intel_syntax — Use Intel syntax rather than AT&T
• .att_syntax — Use AT&T syntax rather than Intel
• .align number — Set the code or data alignment
• .arch name — Set the code architecture
• .arm — Set the ARM mode (as opposed to Thumb) for ARM architecture
• .ascii string — Define the ASCII string
• .asciz string — Define the zero-ending ASCII string
• .bits number — Define the code bitness
• .big_endian — Set the BE (big endian) byte order
• .cpu name — Set the CPU for the chosen architecture
• .data — Mark the start of the data section
• .endian 1|0 — Set the endianness (the byte order) — 1 is BE, 0 is LE
• .equ name value — Define the constant
• .fill repeat,size,value — Fill the data with the repeating value pattern
• .hex data — Define the data in hexadecimal format
• .incbin filename — Include binary file
• .int16 number — Define 16-bit integer
• .int32 number — Define 32-bit integer
• .int64 number — Define 64-bit integer
• .kernel name — Set the kernel for syscalls
• .little_endian — Set the LE (little endian) byte order
• .org value — Set the value of the PC (Program Counter) register
• .os name — Set the operating system for syscalls
• .short number — Define 16-bit integer
• .string string — Define the ASCII string
• .text — Mark the start of the text section
• .thumb — Set the Thumb mode (as opposed to ARM) for ARM architecture

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🦋 ENVIRONMENT 🦋

the env var squad, bestie:

• RZ_ARCH: e asm.arch - architecture to assemble/disassemble (same as rz-asm -a)
• RZ_ASM_ARCH: architecture to assemble/disassemble (same as rz-asm -a)
• RZ_ASM_BITS: cpu register size (8, 16, 32, 64) (same as rz-asm -b)
• RZ_BITS: e asm.bits - cpu register size (8, 16, 32, 64) (same as rz-asm -b)
• RZ_DEBUG: if defined, show error messages and crash signal0
• RZ_NOPLUGINS: do not load shared plugins (speedup loading)0

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🔥 EXAMPLES 🔥

Assemble opcode:

rz-asm -a x86 -b 32 'mov eax, 33'

Disassemble opcode:

rz-asm -d 90

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🌈 SEE ALSO 🌈

the whole squad: rizin(1), rz-find(1), rz-hash(1), rz-bin(1), rz-diff(1), rz-gg(1), rz-run(1), rz-ax(1)

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👑 AUTHORS 👑

• pancake <pancake@nopcode.org>
• byteninjaa0

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💖 that's the whole page, bestie — RZ_ASM(1), dated Jan 22, 2024, signing off. 🎀✨