[PATCH v1 3/5] connector/cn_proc: Test code for proc connector

From: Anjali Kulkarni
Date: Fri Mar 10 2023 - 17:16:24 EST


Test code for proc connector.

Signed-off-by: Anjali Kulkarni <anjali.k.kulkarni@xxxxxxxxxx>
---
samples/connector/proc_filter.c | 262 ++++++++++++++++++++++++++++++++
1 file changed, 262 insertions(+)
create mode 100644 samples/connector/proc_filter.c

diff --git a/samples/connector/proc_filter.c b/samples/connector/proc_filter.c
new file mode 100644
index 000000000000..25202f5bc126
--- /dev/null
+++ b/samples/connector/proc_filter.c
@@ -0,0 +1,262 @@
+// 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>
+
+#define NL_MESSAGE_SIZE (sizeof(struct nlmsghdr) + sizeof(struct cn_msg) + \
+ sizeof(int))
+
+#define MAX_EVENTS 1
+
+#ifdef ENABLE_PRINTS
+#define Printf printf
+#else
+#define Printf
+#endif
+
+volatile static int interrupted;
+static int nl_sock, ret_errno, tcount;
+static struct epoll_event evn;
+
+int send_message(enum proc_cn_mcast_op mcast_op)
+{
+ char buff[NL_MESSAGE_SIZE];
+ struct nlmsghdr *hdr;
+ struct cn_msg *msg;
+
+ hdr = (struct nlmsghdr *)buff;
+ hdr->nlmsg_len = NL_MESSAGE_SIZE;
+ 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;
+
+ msg->len = sizeof(int);
+ *(int *)msg->data = mcast_op;
+
+ 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, enum proc_cn_mcast_op mcast_op)
+{
+ 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(mcast_op);
+ 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(__attribute__((__always_unused)) 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;
+
+ signal(SIGINT, sigint);
+
+ err = register_proc_netlink(&epoll_fd, PROC_CN_MCAST_LISTEN);
+ 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);
+ }
+ }
+
+ send_message(PROC_CN_MCAST_IGNORE);
+
+ close(epoll_fd);
+ close(nl_sock);
+
+ printf("Done total count: %d\n", tcount);
+ exit(0);
+}
--
2.31.1