Add solutionHEADmaster

4 files changed, 43 insertions, 0 deletions

diff --git a/chall/Dockerfile b/chall/Dockerfile
new file mode 100644
index 0000000..9606414
--- /dev/null
+++ b/chall/Dockerfile
@@ -0,0 +1,25 @@
+FROM ubuntu:jammy
+
+RUN apt-get update && apt-get -y install openssh-server file procps
+
+WORKDIR /app
+
+RUN groupadd -r ctf && useradd -m -r -g ctf ctf
+RUN echo "ctf:ctf" | chpasswd
+
+RUN echo 'ForceCommand "/app/checker.sh"' >> /etc/ssh/sshd_config
+RUN echo 'Port 2022' >> /etc/ssh/sshd_config
+RUN mkdir /var/run/sshd
+
+COPY flag.txt /
+COPY checker.sh /app/
+
+RUN chmod 444 /flag.txt
+RUN chmod 555 /app/checker.sh
+
+CMD while true; do \
+        # kill long running processes for ssh
+        ps -eo comm,pid,etimes | awk '/^checker.sh/ {if ($3 > 10) { print $2 }}' | xargs --no-run-if-empty kill -9; \
+        sleep 5s; \
+    done & \
+    /sbin/sshd -D
diff --git a/chall/checker.sh b/chall/checker.sh
new file mode 100644
index 0000000..45f7942
--- /dev/null
+++ b/chall/checker.sh
@@ -0,0 +1,9 @@
+#!/bin/bash
+
+read -p "Input a file path: " filepath
+file $filepath 2>/dev/null | grep -q "ASCII text" 2>/dev/null
+
+# TODO: print the result the above command.
+#   $? == 0 -> It's a text file.
+#   $? != 0 -> It's not a text file.
+exit 0
diff --git a/chall/docker-compose.yml b/chall/docker-compose.yml
new file mode 100644
index 0000000..c13f708
--- /dev/null
+++ b/chall/docker-compose.yml
@@ -0,0 +1,8 @@
+version: "3"
+
+services:
+  challenge:
+    build: .
+    restart: always
+    ports:
+      - 2022:2022
diff --git a/chall/flag.txt b/chall/flag.txt
new file mode 100644
index 0000000..8671e48
--- /dev/null
+++ b/chall/flag.txt
@@ -0,0 +1 @@
+SECCON{dummy}