BIN Loading and Memory Map

Implemented raw .bin loading:

• opens files in binary mode
• maps bytes at --base
• stores the image as one source chunk
• handles empty files
• rejects address overflow
• reports file errors with diagnostics

Extended BlFirmwareImage with owned analysis data:

• reconstructed regions
• gaps
• overlaps

Implemented bl_memmap_reconstruct:

• sorts source chunks by address
• merges adjacent chunks
• merges overlapping chunks while preserving first-seen bytes
• records sparse gaps
• records overlaps as identical or conflicting

CLI output now includes:

• input metadata
• source chunks with -v
• memory regions
• gaps
• overlaps

Added tests:

• test_bin_loader.c
• test_memmap.c

Covered base-address mapping, overflow rejection, adjacent merge, sparse gaps, identical overlaps, and conflicting overlaps.

Entropy and Cortex-M Analysis

Implemented Shannon entropy without requiring -lm, keeping the Makefile dependency-free.

Entropy is now reported:

• per reconstructed region
• per fixed-size chunk in verbose mode
• as an ASCII heatmap with --heatmap

--entropy-chunk controls the chunk size.

Implemented Cortex-M vector table detection:

• checks common aliases like 0x00000000 and 0x08000000
• reads initial SP and reset handler as little-endian words
• validates SRAM stack range
• validates stack alignment
• validates Thumb reset bit
• checks whether reset target lands in loaded firmware
• reports confidence score: none, low, medium, high

Added STM32-like fixture:

• tests/fixtures/stm32_vector.ihex

Added tests:

• test_entropy.c
• test_vector_table.c

Covered known entropy values, heatmap symbols, high-confidence vector detection, missing-vector behavior, and an end-to-end STM32-like HEX sample.

Verification

Native GCC build passed with:

-std=c11 -Wall -Wextra -Wpedantic

Tests passed:

test_bin_loader: ok
test_entropy: ok
test_hex_parser: ok
test_memmap: ok
test_smoke: ok
test_vector_table: ok

Docker POSIX path passed:

make clean
make test
make

Current State

The MVP analysis path is now feature-complete for:

• Intel HEX parsing
• raw BIN loading
• memory layout reconstruction
• gap and overlap reporting
• per-region entropy
• chunk entropy
• ASCII heatmap
• Cortex-M vector table detection

Remaining stretch work includes JSON output, richer heuristics, section guessing, and comparison mode.