Allow to specify options for certain instances only

[wizche]

Implements #39

• Parsing of config file
• Generating command based on the partial flags
• Add a cleanup stage after command is generated in order to merge same env variable (e.g. AFL_PRELOAD)
• Document TOML format

Example TOML:

[target]
# Target binary to fuzz
path = "/bin/ls"

# Target binary arguments, including @@ if needed
args = []

[afl_cfg]
# Amount of processes to spin up
runners = 2

# Custom path to 'afl-fuzz' binary
afl_binary = "/tmp/afl-fuzz"

# Seed corpus directory
seed_dir = "/tmp/in/"

# Solution/Crash output directory
solution_dir = "/tmp/out"

# Token dictionary to use
#dictionary = "/path/to/dictionary"

# Custom AFL flags
afl_flags = "-Q"

# Use afl-fuzz defaults
use_afl_defaults = false

[[afl_cfg.flags_partial]]
probability = 0.5
AFL_USE_QASAN=1

[[afl_cfg.flags_partial]]
probability = 0.2
AFL_PRELOAD = "/path/to/libcompcov.so"
AFL_COMPCOV_LEVEL = 1

[[afl_cfg.flags_partial]]
count = 4
-x = "/tmp/dictionary1"

[[afl_cfg.flags_partial]]
count = 3
-x = "/tmp/dictionary2"

[[afl_cfg.flags_partial]]
probability = 0.4
-G = 1234

[session]
# Spin up a custom tmux session with the fuzzers
dry_run = false

# Custom tmux session name
name = "fuzz"

# Runner backend to use: [tmux, screen]
runner = "tmux"

[misc]
# Enable TUI mode

[0xricksanchez]

@wizche I rewrote most if not all the core-logic of the code to hopefully increase maintainability and having easier access for adding new features.
That said, the bad news is that adding your feature requires a significant rebase now