[PATCH v9 6/6] connector/cn_proc: Selftest for proc connector

Anjali Kulkarni
2023-07-08T02:35:11Z

Run as ./proc_filter -f to run new filter code. Run without "-f" to run
usual proc connector code without the new filtering code.

Signed-off-by: Anjali Kulkarni <anjali.k.kulkarni@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
---
tools/testing/selftests/Makefile | 1 +
tools/testing/selftests/connector/Makefile | 6 +
.../testing/selftests/connector/proc_filter.c | 310 ++++++++++++++++++
3 files changed, 317 insertions(+)
create mode 100644 tools/testing/selftests/connector/Makefile
create mode 100644 tools/testing/selftests/connector/proc_filter.c

diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index 90a62cf75008..7c9673951f9a 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -7,6 +7,7 @@ TARGETS += breakpoints
TARGETS += capabilities
TARGETS += cgroup
TARGETS += clone3
+TARGETS += connector
TARGETS += core
TARGETS += cpufreq
TARGETS += cpu-hotplug
diff --git a/tools/testing/selftests/connector/Makefile b/tools/testing/selftests/connector/Makefile
new file mode 100644
index 000000000000..21c9f3a973a0
--- /dev/null
+++ b/tools/testing/selftests/connector/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+CFLAGS += -Wall
+
+TEST_GEN_PROGS = proc_filter
+
+include ../lib.mk
diff --git a/tools/testing/selftests/connector/proc_filter.c b/tools/testing/selftests/connector/proc_filter.c
new file mode 100644
index 000000000000..4fe8c6763fd8
--- /dev/null
+++ b/tools/testing/selftests/connector/proc_filter.c
@@ -0,0 +1,310 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <sys/types.h>
+#include <sys/epoll.h>
+#include <sys/socket.h>
+#include <linux/netlink.h>
+#include <linux/connector.h>
+#include <linux/cn_proc.h>
+
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <strings.h>
+#include <errno.h>
+#include <signal.h>
+#include <string.h>
+
+#include "../kselftest.h"
+
+#define NL_MESSAGE_SIZE (sizeof(struct nlmsghdr) + sizeof(struct cn_msg) + \
+ sizeof(struct proc_input))
+#define NL_MESSAGE_SIZE_NF (sizeof(struct nlmsghdr) + sizeof(struct cn_msg) + \
+ sizeof(int))
+
+#define MAX_EVENTS 1
+
+volatile static int interrupted;
+static int nl_sock, ret_errno, tcount;
+static struct epoll_event evn;
+
+static int filter;
+
+#ifdef ENABLE_PRINTS
+#define Printf printf
+#else
+#define Printf ksft_print_msg
+#endif
+
+int send_message(void *pinp)
+{
+ char buff[NL_MESSAGE_SIZE];
+ struct nlmsghdr *hdr;
+ struct cn_msg *msg;
+
+ hdr = (struct nlmsghdr *)buff;
+ if (filter)
+ hdr->nlmsg_len = NL_MESSAGE_SIZE;
+ else
+ hdr->nlmsg_len = NL_MESSAGE_SIZE_NF;
+ hdr->nlmsg_type = NLMSG_DONE;
+ hdr->nlmsg_flags = 0;
+ hdr->nlmsg_seq = 0;
+ hdr->nlmsg_pid = getpid();
+
+ msg = (struct cn_msg *)NLMSG_DATA(hdr);
+ msg->id.idx = CN_IDX_PROC;
+ msg->id.val = CN_VAL_PROC;
+ msg->seq = 0;
+ msg->ack = 0;
+ msg->flags = 0;
+
+ if (filter) {
+ msg->len = sizeof(struct proc_input);
+ ((struct proc_input *)msg->data)->mcast_op =
+ ((struct proc_input *)pinp)->mcast_op;
+ ((struct proc_input *)msg->data)->event_type =
+ ((struct proc_input *)pinp)->event_type;
+ } else {
+ msg->len = sizeof(int);
+ *(int *)msg->data = *(enum proc_cn_mcast_op *)pinp;
+ }
+
+ if (send(nl_sock, hdr, hdr->nlmsg_len, 0) == -1) {
+ ret_errno = errno;
+ perror("send failed");
+ return -3;
+ }
+ return 0;
+}
+
+int register_proc_netlink(int *efd, void *input)
+{
+ struct sockaddr_nl sa_nl;
+ int err = 0, epoll_fd;
+
+ nl_sock = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_CONNECTOR);
+
+ if (nl_sock == -1) {
+ ret_errno = errno;
+ perror("socket failed");
+ return -1;
+ }
+
+ bzero(&sa_nl, sizeof(sa_nl));
+ sa_nl.nl_family = AF_NETLINK;
+ sa_nl.nl_groups = CN_IDX_PROC;
+ sa_nl.nl_pid = getpid();
+
+ if (bind(nl_sock, (struct sockaddr *)&sa_nl, sizeof(sa_nl)) == -1) {
+ ret_errno = errno;
+ perror("bind failed");
+ return -2;
+ }
+
+ epoll_fd = epoll_create1(EPOLL_CLOEXEC);
+ if (epoll_fd < 0) {
+ ret_errno = errno;
+ perror("epoll_create1 failed");
+ return -2;
+ }
+
+ err = send_message(input);
+
+ if (err < 0)
+ return err;
+
+ evn.events = EPOLLIN;
+ evn.data.fd = nl_sock;
+ if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, nl_sock, &evn) < 0) {
+ ret_errno = errno;
+ perror("epoll_ctl failed");
+ return -3;
+ }
+ *efd = epoll_fd;
+ return 0;
+}
+
+static void sigint(int sig)
+{
+ interrupted = 1;
+}
+
+int handle_packet(char *buff, int fd, struct proc_event *event)
+{
+ struct nlmsghdr *hdr;
+
+ hdr = (struct nlmsghdr *)buff;
+
+ if (hdr->nlmsg_type == NLMSG_ERROR) {
+ perror("NLMSG_ERROR error\n");
+ return -3;
+ } else if (hdr->nlmsg_type == NLMSG_DONE) {
+ event = (struct proc_event *)
+ ((struct cn_msg *)NLMSG_DATA(hdr))->data;
+ tcount++;
+ switch (event->what) {
+ case PROC_EVENT_EXIT:
+ Printf("Exit process %d (tgid %d) with code %d, signal %d\n",
+ event->event_data.exit.process_pid,
+ event->event_data.exit.process_tgid,
+ event->event_data.exit.exit_code,
+ event->event_data.exit.exit_signal);
+ break;
+ case PROC_EVENT_FORK:
+ Printf("Fork process %d (tgid %d), parent %d (tgid %d)\n",
+ event->event_data.fork.child_pid,
+ event->event_data.fork.child_tgid,
+ event->event_data.fork.parent_pid,
+ event->event_data.fork.parent_tgid);
+ break;
+ case PROC_EVENT_EXEC:
+ Printf("Exec process %d (tgid %d)\n",
+ event->event_data.exec.process_pid,
+ event->event_data.exec.process_tgid);
+ break;
+ case PROC_EVENT_UID:
+ Printf("UID process %d (tgid %d) uid %d euid %d\n",
+ event->event_data.id.process_pid,
+ event->event_data.id.process_tgid,
+ event->event_data.id.r.ruid,
+ event->event_data.id.e.euid);
+ break;
+ case PROC_EVENT_GID:
+ Printf("GID process %d (tgid %d) gid %d egid %d\n",
+ event->event_data.id.process_pid,
+ event->event_data.id.process_tgid,
+ event->event_data.id.r.rgid,
+ event->event_data.id.e.egid);
+ break;
+ case PROC_EVENT_SID:
+ Printf("SID process %d (tgid %d)\n",
+ event->event_data.sid.process_pid,
+ event->event_data.sid.process_tgid);
+ break;
+ case PROC_EVENT_PTRACE:
+ Printf("Ptrace process %d (tgid %d), Tracer %d (tgid %d)\n",
+ event->event_data.ptrace.process_pid,
+ event->event_data.ptrace.process_tgid,
+ event->event_data.ptrace.tracer_pid,
+ event->event_data.ptrace.tracer_tgid);
+ break;
+ case PROC_EVENT_COMM:
+ Printf("Comm process %d (tgid %d) comm %s\n",
+ event->event_data.comm.process_pid,
+ event->event_data.comm.process_tgid,
+ event->event_data.comm.comm);
+ break;
+ case PROC_EVENT_COREDUMP:
+ Printf("Coredump process %d (tgid %d) parent %d, (tgid %d)\n",
+ event->event_data.coredump.process_pid,
+ event->event_data.coredump.process_tgid,
+ event->event_data.coredump.parent_pid,
+ event->event_data.coredump.parent_tgid);
+ break;
+ default:
+ break;
+ }
+ }
+ return 0;
+}
+
+int handle_events(int epoll_fd, struct proc_event *pev)
+{
+ char buff[CONNECTOR_MAX_MSG_SIZE];
+ struct epoll_event ev[MAX_EVENTS];
+ int i, event_count = 0, err = 0;
+
+ event_count = epoll_wait(epoll_fd, ev, MAX_EVENTS, -1);
+ if (event_count < 0) {
+ ret_errno = errno;
+ if (ret_errno != EINTR)
+ perror("epoll_wait failed");
+ return -3;
+ }
+ for (i = 0; i < event_count; i++) {
+ if (!(ev[i].events & EPOLLIN))
+ continue;
+ if (recv(ev[i].data.fd, buff, sizeof(buff), 0) == -1) {
+ ret_errno = errno;
+ perror("recv failed");
+ return -3;
+ }
+ err = handle_packet(buff, ev[i].data.fd, pev);
+ if (err < 0)
+ return err;
+ }
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ int epoll_fd, err;
+ struct proc_event proc_ev;
+ struct proc_input input;
+
+ signal(SIGINT, sigint);
+
+ if (argc > 2) {
+ printf("Expected 0(assume no-filter) or 1 argument(-f)\n");
+ exit(1);
+ }
+
+ if (argc == 2) {
+ if (strcmp(argv[1], "-f") == 0) {
+ filter = 1;
+ } else {
+ printf("Valid option : -f (for filter feature)\n");
+ exit(1);
+ }
+ }
+
+ if (filter) {
+ input.event_type = PROC_EVENT_NONZERO_EXIT;
+ input.mcast_op = PROC_CN_MCAST_LISTEN;
+ err = register_proc_netlink(&epoll_fd, (void*)&input);
+ } else {
+ enum proc_cn_mcast_op op = PROC_CN_MCAST_LISTEN;
+ err = register_proc_netlink(&epoll_fd, (void*)&op);
+ }
+
+ if (err < 0) {
+ if (err == -2)
+ close(nl_sock);
+ if (err == -3) {
+ close(nl_sock);
+ close(epoll_fd);
+ }
+ exit(1);
+ }
+
+ while (!interrupted) {
+ err = handle_events(epoll_fd, &proc_ev);
+ if (err < 0) {
+ if (ret_errno == EINTR)
+ continue;
+ if (err == -2)
+ close(nl_sock);
+ if (err == -3) {
+ close(nl_sock);
+ close(epoll_fd);
+ }
+ exit(1);
+ }
+ }
+
+ if (filter) {
+ input.mcast_op = PROC_CN_MCAST_IGNORE;
+ send_message((void*)&input);
+ } else {
+ enum proc_cn_mcast_op op = PROC_CN_MCAST_IGNORE;
+ send_message((void*)&op);
+ }
+
+ close(epoll_fd);
+ close(nl_sock);
+
+ printf("Done total count: %d\n", tcount);
+ exit(0);
+}
--
2.41.0