Program/docker image that performs bad activities.

C++ program that performs bad activities related to the current falco
ruleset. There are configurable actions for almost all of the current
ruleset, via the --action argument.

By default runs in a loop forever. Can be overridden via --once.

Also add a Dockerfile that compiles event_generator.cpp within an alpine
linux image and copies it to /usr/local/bin. This image has been pushed
to docker hub as "sysdig/falco-event-generator:latest".

Add a Makefile that runs the right docker build command.
This commit is contained in:
Mark Stemm 2016-08-11 16:37:07 -07:00
parent 2aa8a5c114
commit 6e1f23b9a5
4 changed files with 416 additions and 0 deletions

6
.gitignore vendored
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@ -11,3 +11,9 @@ test/results*.json.*
userspace/falco/lua/re.lua
userspace/falco/lua/lpeg.so
docker/event-generator/event-generator
docker/event-generator/mysqld
docker/event-generator/httpd
docker/event-generator/sha1sum
docker/event-generator/vipw

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@ -0,0 +1,6 @@
FROM alpine:latest
RUN apk add --no-cache bash g++
COPY ./event_generator.cpp /usr/local/bin
RUN mkdir -p /var/lib/rpm
RUN g++ --std=c++0x /usr/local/bin/event_generator.cpp -o /usr/local/bin/event_generator
CMD ["/usr/local/bin/event_generator"]

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@ -0,0 +1,2 @@
image:
docker build -t sysdig/falco-event-generator:latest .

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@ -0,0 +1,402 @@
#include <cstdio>
#include <utility>
#include <map>
#include <set>
#include <string>
#include <cstring>
#include <cstdlib>
#include <unistd.h>
#include <getopt.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <pwd.h>
#include <sys/socket.h>
#include <arpa/inet.h>
using namespace std;
void usage(char *program)
{
printf("Usage %s [options]\n\n", program);
printf("Options:\n");
printf(" -h/--help: show this help\n");
printf(" -a/--action: actions to perform. Can be one of the following:\n");
printf(" write_binary_dir Write to files below /bin\n");
printf(" write_etc Write to files below /etc\n");
printf(" read_sensitive_file Read a sensitive file\n");
printf(" read_sensitive_file_after_startup As a trusted program, wait a while,\n");
printf(" then read a sensitive file\n");
printf(" write_rpm_database Write to files below /var/lib/rpm\n");
printf(" spawn_shell Run a shell (bash)\n");
printf(" db_program_spawn_process As a database program, try to spawn\n");
printf(" another program\n");
printf(" modify_binary_dirs Modify a file below /bin\n");
printf(" mkdir_binary_dirs Create a directory below /bin\n");
printf(" change_thread_namespace Change namespace\n");
printf(" system_user_interactive Change to a system user and try to\n");
printf(" run an interactive command\n");
printf(" network_activity Open network connections\n");
printf(" (used by system_procs_network_activity below)\n");
printf(" system_procs_network_activity Open network connections as a program\n");
printf(" that should not perform network actions\n");
printf(" non_sudo_setuid Setuid as a non-root user\n");
printf(" create_files_below_dev Create files below /dev\n");
printf(" exec_ls execve() the program ls\n");
printf(" (used by user_mgmt_binaries below)\n");
printf(" user_mgmt_binaries Become the program \"vipw\", which triggers\n");
printf(" rules related to user management programs\n");
printf(" all All of the above\n");
printf(" -i/--interval: Number of seconds between actions\n");
printf(" -o/--once: Perform actions once and exit\n");
}
void open_file(const char *filename, const char *flags)
{
FILE *f = fopen(filename, flags);
if(f)
{
fclose(f);
}
else
{
fprintf(stderr, "Could not open %s for writing: %s\n", filename, strerror(errno));
}
}
void touch(const char *filename)
{
open_file(filename, "w");
}
void read(const char *filename)
{
open_file(filename, "r");
}
uid_t become_user(const char *user)
{
struct passwd *pw;
pw = getpwnam(user);
if(pw == NULL)
{
fprintf(stderr, "Could not find user information for \"%s\" user: %s\n", user, strerror(errno));
exit(1);
}
int rc = setuid(pw->pw_uid);
if(rc != 0)
{
fprintf(stderr, "Could not change user to \"%s\" (uid %u): %s\n", user, pw->pw_uid, strerror(errno));
exit(1);
}
}
void spawn(const char *cmd, char **argv, char **env)
{
pid_t child;
// Fork a process, that way proc.duration is reset
if ((child = fork()) == 0)
{
execve(cmd, argv, env);
fprintf(stderr, "Could not exec to spawn %s: %s\n", cmd, strerror(errno));
}
else
{
int status;
waitpid(child, &status, 0);
}
}
void respawn(const char *cmd, const char *action, const char *interval)
{
char *argv[] = {(char *) cmd,
(char *) "--action", (char *) action,
(char *) "--interval", (char *) interval,
(char *) "--once", NULL};
char *env[] = {NULL};
spawn(cmd, argv, env);
}
void write_binary_dir() {
printf("Writing to /bin/created-by-event-generator-sh...\n");
touch("/bin/created-by-event-generator-sh");
}
void write_etc() {
printf("Writing to /etc/created-by-event-generator-sh...\n");
touch("/etc/created-by-event-generator-sh");
}
void read_sensitive_file() {
printf("Reading /etc/shadow...\n");
read("/etc/shadow");
}
void read_sensitive_file_after_startup() {
printf("Becoming the program \"httpd\", sleeping 6 seconds and reading /etc/shadow...\n");
respawn("./httpd", "read_sensitive_file", "6");
}
void write_rpm_database() {
printf("Writing to /var/lib/rpm/created-by-event-generator-sh...\n");
touch("/var/lib/rpm/created-by-event-generator-sh");
}
void spawn_shell() {
printf("Spawning a shell using system()...\n");
int rc;
if ((rc = system("ls > /dev/null")) != 0)
{
fprintf(stderr, "Could not run ls > /dev/null in a shell: %s\n", strerror(errno));
}
}
void db_program_spawn_process() {
printf("Becoming the program \"mysql\" and then spawning a shell\n");
respawn("./mysqld", "spawn_shell", "0");
}
void modify_binary_dirs() {
printf("Moving /bin/true to /bin/true.event-generator-sh and back...\n");
if (rename("/bin/true", "/bin/true.event-generator-sh") != 0)
{
fprintf(stderr, "Could not rename \"/bin/true\" to \"/bin/true.event-generator-sh\": %s\n", strerror(errno));
}
else
{
if (rename("/bin/true.event-generator-sh", "/bin/true") != 0)
{
fprintf(stderr, "Could not rename \"/bin/true.event-generator-sh\" to \"/bin/true\": %s\n", strerror(errno));
}
}
}
void mkdir_binary_dirs() {
printf("Creating directory /bin/directory-created-by-event-generator-sh...\n");
if (mkdir("/bin/directory-created-by-event-generator-sh", 0644) != 0)
{
fprintf(stderr, "Could not create directory \"/bin/directory-created-by-event-generator-sh\": %s\n", strerror(errno));
}
}
void change_thread_namespace() {
printf("Calling setns() to change namespaces...\n");
// It doesn't matter that the arguments to setns are
// bogus. It's the attempt to call it that will trigger the
// rule.
setns(0, 0);
}
void system_user_interactive() {
pid_t child;
// Fork a child and do everything in the child.
if ((child = fork()) == 0)
{
become_user("daemon");
char *argv[] = {(char *)"/bin/login", NULL};
char *env[] = {NULL};
spawn("/bin/login", argv, env);
exit(0);
}
else
{
int status;
waitpid(child, &status, 0);
}
}
void network_activity() {
printf("Opening a listening socket on port 8192...\n");
int rc;
int sock = socket(PF_INET, SOCK_DGRAM, 0);
struct sockaddr_in localhost;
localhost.sin_family = AF_INET;
localhost.sin_port = htons(8192);
inet_aton("127.0.0.1", &(localhost.sin_addr));
if((rc = bind(sock, (struct sockaddr *) &localhost, sizeof(localhost))) != 0)
{
fprintf(stderr, "Could not bind listening socket to localhost: %s\n", strerror(errno));
return;
}
listen(sock, 1);
close(sock);
}
void system_procs_network_activity() {
printf("Becoming the program \"sha1sum\" and then performing network activity\n");
respawn("./sha1sum", "network_activity", "0");
}
void non_sudo_setuid() {
pid_t child;
// Fork a child and do everything in the child.
if ((child = fork()) == 0)
{
// First setuid to something non-root. Then try to setuid back to root.
become_user("daemon");
become_user("root");
exit(0);
}
else
{
int status;
waitpid(child, &status, 0);
}
}
void create_files_below_dev() {
printf("Creating /dev/created-by-event-generator-sh...\n");
touch("/dev/created-by-event-generator-sh");
}
void exec_ls()
{
char *argv[] = {(char *)"/bin/ls", NULL};
char *env[] = {NULL};
spawn("/bin/ls", argv, env);
}
void user_mgmt_binaries() {
printf("Becoming the program \"vipw\" and then running the program /bin/ls\n");
printf("NOTE: does not result in a falco notification in containers\n");
respawn("./vipw", "exec_ls", "0");
}
typedef void (*action_t)();
map<string, action_t> defined_actions = {{"write_binary_dir", write_binary_dir},
{"write_etc", write_etc},
{"read_sensitive_file", read_sensitive_file},
{"read_sensitive_file_after_startup", read_sensitive_file_after_startup},
{"write_rpm_database", write_rpm_database},
{"spawn_shell", spawn_shell},
{"db_program_spawn_process", db_program_spawn_process},
{"modify_binary_dirs", modify_binary_dirs},
{"mkdir_binary_dirs", mkdir_binary_dirs},
{"change_thread_namespace", change_thread_namespace},
{"system_user_interactive", system_user_interactive},
{"network_activity", network_activity},
{"system_procs_network_activity", system_procs_network_activity},
{"non_sudo_setuid", non_sudo_setuid},
{"create_files_below_dev", create_files_below_dev},
{"exec_ls", exec_ls},
{"user_mgmt_binaries", user_mgmt_binaries}};
void create_symlinks(const char *program)
{
int rc;
// Some actions depend on this program being re-run as
// different program names like 'mysqld', 'httpd', etc. This
// sets up all the required symlinks.
const char *progs[] = {"./httpd", "./mysqld", "./sha1sum", "./vipw", NULL};
for (unsigned int i=0; progs[i] != NULL; i++)
{
unlink(progs[i]);
if ((rc = symlink(program, progs[i])) != 0)
{
fprintf(stderr, "Could not link \"./event_generator\" to \"%s\": %s\n", progs[i], strerror(errno));
}
}
}
void run_actions(map<string, action_t> &actions, int interval, bool once)
{
while (true)
{
for (auto action : actions)
{
sleep(interval);
printf("***Action %s\n", action.first.c_str());
action.second();
}
if(once)
{
break;
}
}
}
int main(int argc, char **argv)
{
map<string, action_t> actions;
int op;
int long_index = 0;
int interval = 1;
bool once = false;
map<string, action_t>::iterator it;
static struct option long_options[] =
{
{"help", no_argument, 0, 'h' },
{"action", required_argument, 0, 'a' },
{"interval", required_argument, 0, 'i' },
{"once", no_argument, 0, 'o' },
{0, 0}
};
//
// Parse the args
//
while((op = getopt_long(argc, argv,
"ha:i:l:",
long_options, &long_index)) != -1)
{
switch(op)
{
case 'h':
usage(argv[0]);
exit(1);
case 'a':
if((it = defined_actions.find(optarg)) == defined_actions.end())
{
fprintf(stderr, "No action with name \"%s\" known, exiting.\n", optarg);
exit(1);
}
actions.insert(*it);
break;
case 'i':
interval = atoi(optarg);
break;
case 'o':
once = true;
break;
default:
usage(argv[0]);
exit(1);
}
}
if(actions.size() == 0)
{
actions = defined_actions;
}
setvbuf(stdout, NULL, _IONBF, 0);
setvbuf(stderr, NULL, _IONBF, 0);
// Only create symlinks when running as the program event_generator
if (strstr(argv[0], "generator"))
{
create_symlinks(argv[0]);
}
run_actions(actions, interval, once);
}