-
Notifications
You must be signed in to change notification settings - Fork 0
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
- Loading branch information
Showing
5 changed files
with
118 additions
and
0 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,48 @@ | ||
FROM ubuntu:20.04 AS builder | ||
|
||
RUN apt-get update && apt-get install -y gcc make | ||
|
||
WORKDIR /build | ||
|
||
COPY src/* ./ | ||
|
||
RUN make | ||
|
||
FROM ghcr.io/svuctf/base-v2/xinetd:latest | ||
|
||
# Copy initialization script and xinetd configuration | ||
COPY --chmod=500 init.sh /init.sh | ||
COPY xinetd.conf /etc/xinetd.conf | ||
|
||
# Set up the CTF environment | ||
RUN chmod -R 750 /home/ctf && \ | ||
mkdir -p /home/ctf/lib64 && \ | ||
mkdir -p /home/ctf/dev && \ | ||
mkdir -p /home/ctf/bin && \ | ||
mkdir -p /home/ctf/lib/x86_64-linux-gnu && \ | ||
mkdir -p /home/ctf/lib32 | ||
|
||
# Copy necessary libraries from builder stage | ||
COPY --from=builder /lib/x86_64-linux-gnu/libc.so.6 /home/ctf/lib/x86_64-linux-gnu/ | ||
COPY --from=builder /lib/x86_64-linux-gnu/ld-linux-x86-64.so.2 /home/ctf/lib64/ | ||
|
||
# Copy the challenge binary | ||
COPY --from=builder --chmod=500 /build/rop /home/ctf/rop | ||
|
||
# Set up device nodes | ||
RUN mknod /home/ctf/dev/null c 1 3 && \ | ||
mknod /home/ctf/dev/zero c 1 5 && \ | ||
mknod /home/ctf/dev/random c 1 8 && \ | ||
mknod /home/ctf/dev/urandom c 1 9 && \ | ||
chmod 666 /home/ctf/dev/* | ||
|
||
# Copy necessary binaries abd binaries | ||
RUN cp /lib/ld-musl-x86_64.so.1 /home/ctf/lib/ && \ | ||
cp /bin/sh /home/ctf/bin && \ | ||
cp /bin/ls /home/ctf/bin && \ | ||
cp /bin/cat /home/ctf/bin && \ | ||
cp /bin/base64 /home/ctf/bin | ||
|
||
RUN chown -R ctf:ctf /home/ctf | ||
|
||
CMD ["xinetd", "-dontfork"] |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,7 @@ | ||
#!/bin/sh | ||
|
||
echo $GZCTF_FLAG > /home/ctf/flag | ||
chown -R ctf:ctf /home/ctf/flag | ||
unset GZCTF_FLAG | ||
|
||
/usr/sbin/chroot /home/ctf/ /rop |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,12 @@ | ||
CC = gcc | ||
CFLAGS = -Wall -Wextra -Wpedantic -no-pie -m64 | ||
|
||
TARGET = rop | ||
|
||
all: $(TARGET) | ||
|
||
$(TARGET): $(TARGET).c | ||
$(CC) $(CFLAGS) -o $@ $< | ||
|
||
clean: | ||
rm -f $(TARGET) |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,34 @@ | ||
#include <stdio.h> | ||
#include <stdlib.h> | ||
#include <unistd.h> | ||
|
||
char secret[] = "/bin/sh"; | ||
|
||
void init() { | ||
setvbuf(stdin, NULL, _IONBF, 0); | ||
setvbuf(stdout, NULL, _IONBF, 0); | ||
setvbuf(stderr, NULL, _IONBF, 0); | ||
} | ||
|
||
void banner() { | ||
printf(" ___ _ _ __ __ ___ ____ ____ \n"); | ||
printf("/ __)( \\/ )( )( )/ __)(_ _)( ___)\n"); | ||
printf("\\__ \\ \\ / )(__)(( (__ )( )__) \n"); | ||
printf("(___/ \\/ (______)\\___) (__) (__) \n"); | ||
printf("\n"); | ||
printf("Welcome to the SVUCTF HELLOWORLD 2024!\n"); | ||
printf("\n"); | ||
} | ||
|
||
void vuln() { | ||
char buf[64]; | ||
system("echo \"Hello CTFer, what's your name?\""); | ||
read(0, &buf, 256); | ||
} | ||
|
||
int main() { | ||
init(); | ||
banner(); | ||
vuln(); | ||
return 0; | ||
} |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,17 @@ | ||
service ctf | ||
{ | ||
disable = no | ||
id = xinetd | ||
socket_type = stream | ||
protocol = tcp | ||
wait = no | ||
user = root | ||
type = UNLISTED | ||
port = 70 | ||
bind = 0.0.0.0 | ||
server = /init.sh | ||
# safety options | ||
per_source = 10 # the maximum instances of this service per source IP address | ||
rlimit_cpu = 20 # the maximum number of CPU seconds that the service may use | ||
rlimit_as = 100M # the Address Space resource limit for the service | ||
} |