fix hotplug

1 files changed, 430 insertions, 2 deletions

diff --git a/hotplug.c b/hotplug.c
index 7e681f9..6583de4 100644
--- a/hotplug.c
+++ b/hotplug.c
@@ -1,10 +1,438 @@
+/*
+ * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
+ * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1
+ * as published by the Free Software Foundation
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+
+#include <linux/types.h>
+#include <linux/netlink.h>
+
+#include <libubox/blobmsg_json.h>
+#include <libubox/json_script.h>
+#include <libubox/uloop.h>
+
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <libgen.h>
+
+#include "procd.h"
 #include "hotplug.h"
 
-void rule_handle_command(const char *name, struct blob_attr *data)
+#define HOTPLUG_WAIT	500
+
+struct cmd_queue {
+	struct list_head list;
+
+	struct blob_attr *msg;
+	struct blob_attr *data;
+	void (*handler)(struct blob_attr *msg, struct blob_attr *data);
+};
+
+static LIST_HEAD(cmd_queue);
+static struct uloop_process queue_proc;
+static struct uloop_timeout last_event;
+static struct blob_buf b;
+static char *rule_file;
+static struct blob_buf script;
+
+static char *hotplug_msg_find_var(struct blob_attr *msg, const char *name)
+{
+	struct blob_attr *cur;
+	int rem;
+
+	blobmsg_for_each_attr(cur, msg, rem) {
+		if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
+			continue;
+
+		if (strcmp(blobmsg_name(cur), name) != 0)
+			continue;
+
+		return blobmsg_data(cur);
+	}
+
+	return NULL;
+}
+
+static void handle_makedev(struct blob_attr *msg, struct blob_attr *data)
 {
+	static struct blobmsg_policy mkdev_policy[2] = {
+		{ .type = BLOBMSG_TYPE_STRING },
+		{ .type = BLOBMSG_TYPE_STRING },
+	};
+	struct blob_attr *tb[2];
+	char *minor = hotplug_msg_find_var(msg, "MINOR");
+	char *major = hotplug_msg_find_var(msg, "MAJOR");
+	char *subsystem = hotplug_msg_find_var(msg, "SUBSYSTEM");
+
+	blobmsg_parse_array(mkdev_policy, 2, tb, blobmsg_data(data), blobmsg_data_len(data));
+	if (tb[0] && tb[1] && minor && major && subsystem) {
+		mode_t m = S_IFCHR;
+		if (!strcmp(subsystem, "block"))
+			m = S_IFBLK;
+		mknod(blobmsg_get_string(tb[0]),
+				m | strtoul(blobmsg_data(tb[1]), NULL, 8),
+				makedev(atoi(major), atoi(minor)));
+	}
 }
 
-void rule_error(struct blob_attr *cur, const char *msg)
+static void handle_rm(struct blob_attr *msg, struct blob_attr *data)
 {
+	static struct blobmsg_policy rm_policy = {
+		.type = BLOBMSG_TYPE_STRING,
+	};
+	struct blob_attr *tb;
+
+	blobmsg_parse_array(&rm_policy, 1, &tb, blobmsg_data(data), blobmsg_data_len(data));
+	if (tb)
+		unlink(blobmsg_data(tb));
+}
+
+static void handle_exec(struct blob_attr *msg, struct blob_attr *data)
+{
+	char *argv[8];
+	struct blob_attr *cur;
+	int rem;
+	int i = 0;
+
+	blobmsg_for_each_attr(cur, msg, rem)
+		setenv(blobmsg_name(cur), blobmsg_data(cur), 1);
+
+	blobmsg_for_each_attr(cur, data, rem) {
+		argv[i] = blobmsg_data(cur);
+		i++;
+		if (i == 7)
+			break;
+	}
+
+	if (debug < 2) {
+		close(STDIN_FILENO);
+		close(STDOUT_FILENO);
+		close(STDERR_FILENO);
+	}
+
+	if (i > 0) {
+		argv[i] = NULL;
+		execvp(argv[0], &argv[0]);
+	}
+	exit(-1);
+}
+
+static void handle_firmware(struct blob_attr *msg, struct blob_attr *data)
+{
+	char *dir = blobmsg_get_string(blobmsg_data(data));
+	char *file = hotplug_msg_find_var(msg, "FIRMWARE");
+	char *dev = hotplug_msg_find_var(msg, "DEVPATH");
+	void *fw_data;
+	struct stat s;
+	char *path, loadpath[256], syspath[256];
+	int fw, load, sys, len;
+
+	DEBUG(1, "Firmware request for %s/%s\n", dir, file);
+
+	if (!file || !dir || !dev) {
+		ERROR("Request for unknown firmware %s/%s\n", dir, file);
+		exit(-1);
+	}
+
+	path = malloc(strlen(dir) + strlen(file) + 2);
+	if (!path) {
+		ERROR("Failed to allocate memory\n");
+		exit(-1);
+	}
+	sprintf(path, "%s/%s", dir, file);
+
+	if (stat(path, &s)) {
+		ERROR("Could not find firmware %s\n", path);
+		exit(-1);
+	}
+
+	fw_data = malloc(s.st_size);
+	if (!fw_data) {
+		ERROR("Failed to allocate firmware data memory\n");
+		exit(-1);
+	}
+
+	fw = open(path, O_RDONLY);
+	if (!fw) {
+		ERROR("Failed to open %s\n", path);
+		exit(-1);
+	}
+	if (read(fw, fw_data, s.st_size) != s.st_size) {
+		ERROR("Failed to read firmware data\n");
+		exit(-1);
+	}
+	close(fw);
+
+	snprintf(loadpath, sizeof(loadpath), "/sys/%s/loading", dev);
+	load = open(loadpath, O_WRONLY);
+	if (!load) {
+		ERROR("Failed to open %s\n", loadpath);
+		exit(-1);
+	}
+	write(load, "1", 1);
+	close(load);
+
+	snprintf(syspath, sizeof(syspath), "/sys/%s/data", dev);
+	sys = open(syspath, O_WRONLY);
+	if (!sys) {
+		ERROR("Failed to open %s\n", syspath);
+		exit(-1);
+	}
+
+	len = s.st_size;
+	while (len > 4096) {
+		write(fw, fw_data, 4096);
+		len -= 4096;
+	}
+	if (len)
+		write(fw, fw_data, len);
+	close(fw);
+
+	load = open(loadpath, O_WRONLY);
+	write(load, "0", 1);
+	close(load);
+
+	DEBUG(1, "Done loading %s\n", path);
+
+	exit(-1);
+}
+
+static struct cmd_handler {
+	char *name;
+	int atomic;
+	void (*handler)(struct blob_attr *msg, struct blob_attr *data);
+} handlers[] = {
+	{
+		.name = "makedev",
+		.atomic = 1,
+		.handler = handle_makedev,
+	}, {
+		.name = "rm",
+		.atomic = 1,
+		.handler = handle_rm,
+	}, {
+		.name = "exec",
+		.handler = handle_exec,
+	}, {
+		.name = "load-firmware",
+		.handler = handle_firmware,
+	},
+};
+
+static void queue_next(void)
+{
+	struct cmd_queue *c;
+
+	if (queue_proc.pending || list_empty(&cmd_queue))
+		return;
+
+	c = list_first_entry(&cmd_queue, struct cmd_queue, list);
+
+	queue_proc.pid = fork();
+	if (!queue_proc.pid) {
+		c->handler(c->msg, c->data);
+		exit(0);
+	}
+
+	list_del(&c->list);
+	free(c);
+
+	if (queue_proc.pid <= 0) {
+		queue_next();
+		return;
+	}
+
+	uloop_process_add(&queue_proc);
+
+	DEBUG(2, "Launched hotplug exec instance, pid=%d\n", (int) queue_proc.pid);
 }
 
+static void queue_proc_cb(struct uloop_process *c, int ret)
+{
+	DEBUG(2, "Finished hotplug exec instance, pid=%d\n", (int) c->pid);
+
+	queue_next();
+}
+
+static void queue_add(struct cmd_handler *h, struct blob_attr *msg, struct blob_attr *data)
+{
+	struct cmd_queue *c = NULL;
+	struct blob_attr *_msg, *_data;
+
+	c = calloc_a(sizeof(struct cmd_queue),
+		&_msg, blob_pad_len(msg),
+		&_data, blob_pad_len(data),
+		NULL);
+
+	c->msg = _msg;
+	c->data = _data;
+
+	if (!c)
+		return;
+
+	memcpy(c->msg, msg, blob_pad_len(msg));
+	memcpy(c->data, data, blob_pad_len(data));
+	c->handler = h->handler;
+	list_add_tail(&c->list, &cmd_queue);
+	queue_next();
+}
+
+static const char* rule_handle_var(struct json_script_ctx *ctx, const char *name, struct blob_attr *vars)
+{
+	const char *str, *sep;
+
+	if (!strcmp(name, "DEVICENAME") || !strcmp(name, "DEVNAME")) {
+		str = json_script_find_var(ctx, vars, "DEVPATH");
+		if (!str)
+			return NULL;
+
+		sep = strrchr(str, '/');
+		if (sep)
+			return sep + 1;
+
+		return str;
+	}
+
+	return NULL;
+}
+
+static struct json_script_file *
+rule_handle_file(struct json_script_ctx *ctx, const char *name)
+{
+	json_object *obj;
+
+	obj = json_object_from_file((char*)name);
+	if (is_error(obj))
+		return NULL;
+
+	blob_buf_init(&script, 0);
+	blobmsg_add_json_element(&script, "", obj);
+
+	return json_script_file_from_blobmsg(name, blob_data(script.head), blob_len(script.head));
+}
+
+static void rule_handle_command(struct json_script_ctx *ctx, const char *name,
+				struct blob_attr *data, struct blob_attr *vars)
+{
+	struct blob_attr *cur;
+	int rem, i;
+
+	if (debug > 1) {
+		DEBUG(2, "Command: %s", name);
+		blobmsg_for_each_attr(cur, data, rem)
+			DEBUG(2, " %s", (char *) blobmsg_data(cur));
+		DEBUG(2, "\n");
+
+		DEBUG(2, "Message:");
+		blobmsg_for_each_attr(cur, vars, rem)
+			DEBUG(2, " %s=%s", blobmsg_name(cur), (char *) blobmsg_data(cur));
+		DEBUG(2, "\n");
+	}
+
+	for (i = 0; i < ARRAY_SIZE(handlers); i++)
+		if (!strcmp(handlers[i].name, name)) {
+			if (handlers[i].atomic)
+				handlers[i].handler(vars, data);
+			else
+				queue_add(&handlers[i], vars, data);
+			break;
+		}
+
+	if (last_event.cb)
+		uloop_timeout_set(&last_event, HOTPLUG_WAIT);
+}
+
+static void rule_handle_error(struct json_script_ctx *ctx, const char *msg,
+				struct blob_attr *context)
+{
+	char *s;
+
+	s = blobmsg_format_json(context, false);
+	ERROR("ERROR: %s in block: %s\n", msg, s);
+	free(s);
+}
+
+static struct json_script_ctx jctx = {
+	.handle_var = rule_handle_var,
+	.handle_error = rule_handle_error,
+	.handle_command = rule_handle_command,
+	.handle_file = rule_handle_file,
+};
+
+static void hotplug_handler(struct uloop_fd *u, unsigned int ev)
+{
+	int i = 0;
+	static char buf[4096];
+	int len = recv(u->fd, buf, sizeof(buf), MSG_DONTWAIT);
+	void *index;
+	if (len < 1)
+		return;
+
+	blob_buf_init(&b, 0);
+	index = blobmsg_open_table(&b, NULL);
+	while (i < len) {
+		int l = strlen(buf + i) + 1;
+		char *e = strstr(&buf[i], "=");
+
+		if (e) {
+			*e = '\0';
+			blobmsg_add_string(&b, &buf[i], &e[1]);
+		}
+		i += l;
+	}
+	blobmsg_close_table(&b, index);
+	DEBUG(3, "%s\n", blobmsg_format_json(b.head, true));
+	json_script_run(&jctx, rule_file, blob_data(b.head));
+}
+
+static struct uloop_fd hotplug_fd = {
+	.cb = hotplug_handler,
+};
+
+void hotplug_last_event(uloop_timeout_handler handler)
+{
+	last_event.cb = handler;
+	if (handler)
+		uloop_timeout_set(&last_event, HOTPLUG_WAIT);
+	else
+		uloop_timeout_cancel(&last_event);
+}
+
+void hotplug(char *rules)
+{
+	struct sockaddr_nl nls;
+
+	rule_file = strdup(rules);
+	memset(&nls,0,sizeof(struct sockaddr_nl));
+	nls.nl_family = AF_NETLINK;
+	nls.nl_pid = getpid();
+	nls.nl_groups = -1;
+
+	if ((hotplug_fd.fd = socket(PF_NETLINK, SOCK_DGRAM | SOCK_CLOEXEC, NETLINK_KOBJECT_UEVENT)) == -1) {
+		ERROR("Failed to open hotplug socket\n");
+		perror("socket");
+		exit(1);
+	}
+	if (bind(hotplug_fd.fd, (void *)&nls, sizeof(struct sockaddr_nl))) {
+		ERROR("Failed to bind hotplug socket\n");
+		perror("socket");
+		exit(1);
+	}
+
+	json_script_init(&jctx);
+	queue_proc.cb = queue_proc_cb;
+	uloop_fd_add(&hotplug_fd, ULOOP_READ);
+}