Tools: hv: kvp: use misc char device to communicate with kernel (8ddca808) · Commits · e / devices / android_kernel_fairphone_FP3

tools/hv/hv_kvp_daemon.c

+31 −135

Original line number	Original line	Diff line number	Diff line
	@@ -33,7 +33,6 @@
	#include <ctype.h>		#include <ctype.h>
	#include <errno.h>		#include <errno.h>
	#include <arpa/inet.h>		#include <arpa/inet.h>
	#include <linux/connector.h>
	#include <linux/hyperv.h>		#include <linux/hyperv.h>
	#include <linux/netlink.h>		#include <linux/netlink.h>
	#include <ifaddrs.h>		#include <ifaddrs.h>
	@@ -79,7 +78,6 @@ enum {
	DNS		DNS
	};		};

	static struct sockaddr_nl addr;
	static int in_hand_shake = 1;		static int in_hand_shake = 1;

	static char *os_name = "";		static char *os_name = "";
	@@ -1387,34 +1385,6 @@ kvp_get_domain_name(char *buffer, int length)
	freeaddrinfo(info);		freeaddrinfo(info);
	}		}

	static int
	netlink_send(int fd, struct cn_msg *msg)
	{
	struct nlmsghdr nlh = { .nlmsg_type = NLMSG_DONE };
	unsigned int size;
	struct msghdr message;
	struct iovec iov[2];

	size = sizeof(struct cn_msg) + msg->len;

	nlh.nlmsg_pid = getpid();
	nlh.nlmsg_len = NLMSG_LENGTH(size);

	iov[0].iov_base = &nlh;
	iov[0].iov_len = sizeof(nlh);

	iov[1].iov_base = msg;
	iov[1].iov_len = size;

	memset(&message, 0, sizeof(message));
	message.msg_name = &addr;
	message.msg_namelen = sizeof(addr);
	message.msg_iov = iov;
	message.msg_iovlen = 2;

	return sendmsg(fd, &message, 0);
	}

	void print_usage(char *argv[])		void print_usage(char *argv[])
	{		{
	fprintf(stderr, "Usage: %s [options]\n"		fprintf(stderr, "Usage: %s [options]\n"
	@@ -1425,22 +1395,17 @@ void print_usage(char *argv[])

	int main(int argc, char *argv[])		int main(int argc, char *argv[])
	{		{
	int fd, len, nl_group;		int kvp_fd, len;
	int error;		int error;
	struct cn_msg *message;
	struct pollfd pfd;		struct pollfd pfd;
	struct nlmsghdr *incoming_msg;
	struct cn_msg *incoming_cn_msg;
	struct hv_kvp_msg *hv_msg;
	char *p;		char *p;
			struct hv_kvp_msg hv_msg[1];
	char *key_value;		char *key_value;
	char *key_name;		char *key_name;
	int op;		int op;
	int pool;		int pool;
	char *if_name;		char *if_name;
	struct hv_kvp_ipaddr_value *kvp_ip_val;		struct hv_kvp_ipaddr_value *kvp_ip_val;
	char *kvp_recv_buffer;
	size_t kvp_recv_buffer_len;
	int daemonize = 1, long_index = 0, opt;		int daemonize = 1, long_index = 0, opt;

	static struct option long_options[] = {		static struct option long_options[] = {
	@@ -1468,12 +1433,14 @@ int main(int argc, char *argv[])
	openlog("KVP", 0, LOG_USER);		openlog("KVP", 0, LOG_USER);
	syslog(LOG_INFO, "KVP starting; pid is:%d", getpid());		syslog(LOG_INFO, "KVP starting; pid is:%d", getpid());

	kvp_recv_buffer_len = NLMSG_LENGTH(0) + sizeof(struct cn_msg) + sizeof(struct hv_kvp_msg);		kvp_fd = open("/dev/vmbus/hv_kvp", O_RDWR);
	kvp_recv_buffer = calloc(1, kvp_recv_buffer_len);
	if (!kvp_recv_buffer) {		if (kvp_fd < 0) {
	syslog(LOG_ERR, "Failed to allocate netlink buffer");		syslog(LOG_ERR, "open /dev/vmbus/hv_kvp failed; error: %d %s",
			errno, strerror(errno));
	exit(EXIT_FAILURE);		exit(EXIT_FAILURE);
	}		}

	/*		/*
	* Retrieve OS release information.		* Retrieve OS release information.
	*/		*/
	@@ -1489,100 +1456,44 @@ int main(int argc, char *argv[])
	exit(EXIT_FAILURE);		exit(EXIT_FAILURE);
	}		}

	fd = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_CONNECTOR);
	if (fd < 0) {
	syslog(LOG_ERR, "netlink socket creation failed; error: %d %s", errno,
	strerror(errno));
	exit(EXIT_FAILURE);
	}
	addr.nl_family = AF_NETLINK;
	addr.nl_pad = 0;
	addr.nl_pid = 0;
	addr.nl_groups = 0;


	error = bind(fd, (struct sockaddr *)&addr, sizeof(addr));
	if (error < 0) {
	syslog(LOG_ERR, "bind failed; error: %d %s", errno, strerror(errno));
	close(fd);
	exit(EXIT_FAILURE);
	}
	nl_group = CN_KVP_IDX;

	if (setsockopt(fd, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &nl_group, sizeof(nl_group)) < 0) {
	syslog(LOG_ERR, "setsockopt failed; error: %d %s", errno, strerror(errno));
	close(fd);
	exit(EXIT_FAILURE);
	}

	/*		/*
	* Register ourselves with the kernel.		* Register ourselves with the kernel.
	*/		*/
	message = (struct cn_msg *)kvp_recv_buffer;
	message->id.idx = CN_KVP_IDX;
	message->id.val = CN_KVP_VAL;

	hv_msg = (struct hv_kvp_msg *)message->data;
	hv_msg->kvp_hdr.operation = KVP_OP_REGISTER1;		hv_msg->kvp_hdr.operation = KVP_OP_REGISTER1;
	message->ack = 0;		len = write(kvp_fd, hv_msg, sizeof(struct hv_kvp_msg));
	message->len = sizeof(struct hv_kvp_msg);		if (len != sizeof(struct hv_kvp_msg)) {
			syslog(LOG_ERR, "registration to kernel failed; error: %d %s",
	len = netlink_send(fd, message);		errno, strerror(errno));
	if (len < 0) {		close(kvp_fd);
	syslog(LOG_ERR, "netlink_send failed; error: %d %s", errno, strerror(errno));
	close(fd);
	exit(EXIT_FAILURE);		exit(EXIT_FAILURE);
	}		}

	pfd.fd = fd;		pfd.fd = kvp_fd;

	while (1) {		while (1) {
	struct sockaddr addr_p = (struct sockaddr ) &addr;
	socklen_t addr_l = sizeof(addr);
	pfd.events = POLLIN;		pfd.events = POLLIN;
	pfd.revents = 0;		pfd.revents = 0;

	if (poll(&pfd, 1, -1) < 0) {		if (poll(&pfd, 1, -1) < 0) {
	syslog(LOG_ERR, "poll failed; error: %d %s", errno, strerror(errno));		syslog(LOG_ERR, "poll failed; error: %d %s", errno, strerror(errno));
	if (errno == EINVAL) {		if (errno == EINVAL) {
	close(fd);		close(kvp_fd);
	exit(EXIT_FAILURE);		exit(EXIT_FAILURE);
	}		}
	else		else
	continue;		continue;
	}		}

	len = recvfrom(fd, kvp_recv_buffer, kvp_recv_buffer_len, 0,		len = read(kvp_fd, hv_msg, sizeof(struct hv_kvp_msg));
	addr_p, &addr_l);

	if (len < 0) {
	int saved_errno = errno;
	syslog(LOG_ERR, "recvfrom failed; pid:%u error:%d %s",
	addr.nl_pid, errno, strerror(errno));

	if (saved_errno == ENOBUFS) {		if (len != sizeof(struct hv_kvp_msg)) {
	syslog(LOG_ERR, "receive error: ignored");		syslog(LOG_ERR, "read failed; error:%d %s",
	continue;		errno, strerror(errno));
	}

	close(fd);
	return -1;
	}

	if (addr.nl_pid) {		close(kvp_fd);
	syslog(LOG_WARNING, "Received packet from untrusted pid:%u",		return EXIT_FAILURE;
	addr.nl_pid);
	continue;
	}		}

	incoming_msg = (struct nlmsghdr *)kvp_recv_buffer;

	if (incoming_msg->nlmsg_type != NLMSG_DONE)
	continue;

	incoming_cn_msg = (struct cn_msg *)NLMSG_DATA(incoming_msg);
	hv_msg = (struct hv_kvp_msg *)incoming_cn_msg->data;

	/*		/*
	* We will use the KVP header information to pass back		* We will use the KVP header information to pass back
	* the error from this daemon. So, first copy the state		* the error from this daemon. So, first copy the state
	@@ -1702,7 +1613,6 @@ int main(int argc, char *argv[])
	goto kvp_done;		goto kvp_done;
	}		}

	hv_msg = (struct hv_kvp_msg *)incoming_cn_msg->data;
	key_name = (char *)hv_msg->body.kvp_enum_data.data.key;		key_name = (char *)hv_msg->body.kvp_enum_data.data.key;
	key_value = (char *)hv_msg->body.kvp_enum_data.data.value;		key_value = (char *)hv_msg->body.kvp_enum_data.data.value;

	@@ -1753,31 +1663,17 @@ int main(int argc, char *argv[])
	hv_msg->error = HV_S_CONT;		hv_msg->error = HV_S_CONT;
	break;		break;
	}		}
	/*
	* Send the value back to the kernel. The response is
	* already in the receive buffer. Update the cn_msg header to
	* reflect the key value that has been added to the message
	*/
	kvp_done:

	incoming_cn_msg->id.idx = CN_KVP_IDX;		/* Send the value back to the kernel. */
	incoming_cn_msg->id.val = CN_KVP_VAL;		kvp_done:
	incoming_cn_msg->ack = 0;		len = write(kvp_fd, hv_msg, sizeof(struct hv_kvp_msg));
	incoming_cn_msg->len = sizeof(struct hv_kvp_msg);		if (len != sizeof(struct hv_kvp_msg)) {
			syslog(LOG_ERR, "write failed; error: %d %s", errno,
	len = netlink_send(fd, incoming_cn_msg);
	if (len < 0) {
	int saved_errno = errno;
	syslog(LOG_ERR, "net_link send failed; error: %d %s", errno,
	strerror(errno));		strerror(errno));

	if (saved_errno == ENOMEM \|\| saved_errno == ENOBUFS) {
	syslog(LOG_ERR, "send error: ignored");
	continue;
	}

	exit(EXIT_FAILURE);		exit(EXIT_FAILURE);
	}		}
	}		}

			close(kvp_fd);
			exit(0);
	}		}