challenge release

.gitignore

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+/build
+/build
+*/build
+/out
+/pack
+.cache

CMakeLists.txt

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+cmake_minimum_required(VERSION 3.20)
+project(rp2sm_chall LANGUAGES CXX)
+
+# GLOBAL COMPILE SETTINGS
+# TODO: should be moved into a utility library somewhere probably
+include(CheckPIESupported)
+check_pie_supported()
+
+include(CheckCXXCompilerFlag)
+
+set(CMAKE_POSITION_INDEPENDENT_CODE ON)
+check_cxx_compiler_flag(-fstack-protector-strong has_stack_protector_strong)
+if(has_stack_protector_strong)
+	add_compile_options(-fstack-protector-strong)
+else()
+	check_cxx_compiler_flag(-fstack-protector has_stack_protector)
+	if(has_stack_protector)
+		add_compile_options(-fstack-protector)
+	else()
+		message(WARNING "Stack protector could not be enabled")
+	endif()
+endif()
+# TODO: use tests
+add_link_options(LINKER:--sort-common,--as-needed,-z,relro,-z,now)
+
+# MAIN CODE
+
+add_subdirectory(rp2sm)
+
+add_executable(chall
+	chall/main.cpp
+)
+target_link_libraries(chall rp2sm)
+
+# packing
+set(CPACK_PACKAGE_FILE_NAME "${CMAKE_PROJECT_NAME}")
+include(CPack)
+install(TARGETS chall rp2sm)
+set_target_properties(chall PROPERTIES INSTALL_RPATH "\${ORIGIN}/../lib")

CMakePresets.json

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+{
+  "version": 2,
+  "cmakeMinimumRequired": {
+    "major": 3,
+    "minor": 20,
+    "patch": 0
+  },
+  "configurePresets": [
+    {
+      "name": "default",
+      "generator": "Ninja Multi-Config",
+      "binaryDir": "build",
+      "cacheVariables": {
+        "CMAKE_EXPORT_COMPILE_COMMANDS": "ON",
+        "CMAKE_CXX_FLAGS_RELWITHDEBINFO": "-O3 -g -DNDEBUG",
+        "CMAKE_CXX_FLAGS_DEBUG": "-Og -g",
+        "CMAKE_BUILD_RPATH_USE_ORIGIN": "ON",
+        "CPACK_GENERATOR": "TGZ"
+      },
+      "environment": {
+        "CC": "clang",
+        "CXX": "clang++"
+      }
+    },
+    {
+      "name": "docker",
+      "inherits": "default",
+      "generator": "Unix Makefiles",
+      "cacheVariables": {
+        "CMAKE_BUILD_TYPE": "Release"
+      }
+    }
+  ]
+}

Makefile

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+DOCKER ?= docker
+DOCKER-BUILD ?= $(DOCKER) buildx build
+GIT ?= git
+TAR ?= tar # must be GNU tar
+TARFLAGS := --numeric-owner --owner=0 --group=0 --sort=name --mtime=1970-01-01T00:00Z --no-xattr $(TARFLAGS)
+
+dist_files = $(shell $(GIT) ls-files deploy) $(shell find out -type f) run.Dockerfile
+source_files = $(dist_files) flag1.txt flag2.txt solve/loader.py solve/stg1.rp2b solve/stg2.rp2b
+tar_transform = --transform 's|^|rp2sm/|;s|\brun\.Dockerfile\b|Dockerfile|'
+
+.PHONY: default
+default: help
+
+.PHONY: all
+all: pack/source.tar pack/dist.tar out
+	@true
+
+.PHONY: out
+out:
+	$(DOCKER-BUILD) . -f build.Dockerfile --target extractor -o type=local,dest=out
+
+out/%: out
+	@# dummy dependency resolution target
+	@true
+
+pack/source.tar: $(source_files)
+	@mkdir -p pack
+	$(TAR) $(TARFLAGS) $(tar_transform) -cf $@ $^
+
+pack/dist.tar: $(dist_files)
+	@mkdir -p pack
+	$(TAR) $(TARFLAGS) $(tar_transform) -cf $@ $^
+
+.PHONY: help
+help:
+	@echo "Available targets:"
+	@echo ""
+	@echo "    out:              compile binaries (in out/)"
+	@echo "    pack/source.tar:  create \"source\" tarball (for challenge builds)"
+	@echo "    pack/dist.tar:    create player-facing tarball"
+	@echo "    all:              all of the above"

README.md

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+# rp2sm
+
+A rev/pwn challenge for [redpwnCTF 2021](https://github.com/redpwn/redpwnctf-2021-challenges).
+
+Some rough notes I made for myself are in [notes.md](notes.md). The assembler
+I wrote is in [assembler/assembler.hs](assembler/assembler.hs), and is used for
+assembling the solutions in [solve/](solve/). Reproducible builds of challenge
+artifacts are done with Docker; `make out` will build the binaries, and
+`make pack/dist.tar` creates the tarball of files distrbuted to competitors.
+
+[Author writeup](https://ethanwu.dev/blog/2021/07/14/redpwn-ctf-2021-rp2sm/)

assembler/.gitignore

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+*.hi
+*.o
+assembler