[deliverable/linux.git] / arch / um / drivers / mconsole_user.c

/*
 * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org)
 * Copyright (C) 2001 - 2003 Jeff Dike (jdike@addtoit.com)
 * Licensed under the GPL
 */

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <signal.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <sys/un.h>
#include <unistd.h>
#include "user.h"
#include "mconsole.h"
#include "umid.h"

static struct mconsole_command commands[] = {
	/* With uts namespaces, uts information becomes process-specific, so
	 * we need a process context.  If we try handling this in interrupt
	 * context, we may hit an exiting process without a valid uts
	 * namespace.
	 */
	{ "version", mconsole_version, MCONSOLE_PROC },
	{ "halt", mconsole_halt, MCONSOLE_PROC },
	{ "reboot", mconsole_reboot, MCONSOLE_PROC },
	{ "config", mconsole_config, MCONSOLE_PROC },
	{ "remove", mconsole_remove, MCONSOLE_PROC },
	{ "sysrq", mconsole_sysrq, MCONSOLE_INTR },
	{ "help", mconsole_help, MCONSOLE_INTR },
	{ "cad", mconsole_cad, MCONSOLE_INTR },
	{ "stop", mconsole_stop, MCONSOLE_PROC },
	{ "go", mconsole_go, MCONSOLE_INTR },
	{ "log", mconsole_log, MCONSOLE_INTR },
	{ "proc", mconsole_proc, MCONSOLE_PROC },
        { "stack", mconsole_stack, MCONSOLE_INTR },
};

/* Initialized in mconsole_init, which is an initcall */
char mconsole_socket_name[256];

int mconsole_reply_v0(struct mc_request *req, char *reply)
{
        struct iovec iov;
        struct msghdr msg;

        iov.iov_base = reply;
        iov.iov_len = strlen(reply);

        msg.msg_name = &(req->origin);
        msg.msg_namelen = req->originlen;
        msg.msg_iov = &iov;
        msg.msg_iovlen = 1;
        msg.msg_control = NULL;
        msg.msg_controllen = 0;
        msg.msg_flags = 0;

        return sendmsg(req->originating_fd, &msg, 0);
}

static struct mconsole_command *mconsole_parse(struct mc_request *req)
{
	struct mconsole_command *cmd;
	int i;

	for(i=0;i<sizeof(commands)/sizeof(commands[0]);i++){
		cmd = &commands[i];
		if(!strncmp(req->request.data, cmd->command, 
			    strlen(cmd->command))){
			return(cmd);
		}
	}
	return(NULL);
}

#define MIN(a,b) ((a)<(b) ? (a):(b))

#define STRINGX(x) #x
#define STRING(x) STRINGX(x)

int mconsole_get_request(int fd, struct mc_request *req)
{
	int len;

	req->originlen = sizeof(req->origin);
	req->len = recvfrom(fd, &req->request, sizeof(req->request), 0,
			    (struct sockaddr *) req->origin, &req->originlen);
	if (req->len < 0)
		return 0;

	req->originating_fd = fd;

	if(req->request.magic != MCONSOLE_MAGIC){
		/* Unversioned request */
		len = MIN(sizeof(req->request.data) - 1, 
			  strlen((char *) &req->request));
		memmove(req->request.data, &req->request, len);
		req->request.data[len] = '\0';

		req->request.magic = MCONSOLE_MAGIC;
		req->request.version = 0;
		req->request.len = len;

		mconsole_reply_v0(req, "ERR Version 0 mconsole clients are "
				  "not supported by this driver");
		return(0);
	}

	if(req->request.len >= MCONSOLE_MAX_DATA){
		mconsole_reply(req, "Request too large", 1, 0);
		return(0);
	}
	if(req->request.version != MCONSOLE_VERSION){
		mconsole_reply(req, "This driver only supports version " 
                               STRING(MCONSOLE_VERSION) " clients", 1, 0);
	}
	
	req->request.data[req->request.len] = '\0';
	req->cmd = mconsole_parse(req);
	if(req->cmd == NULL){
		mconsole_reply(req, "Unknown command", 1, 0);
		return(0);
	}

	return(1);
}

int mconsole_reply_len(struct mc_request *req, const char *str, int total,
		       int err, int more)
{
	struct mconsole_reply reply;
	int len, n;

	do {
		reply.err = err;

		/* err can only be true on the first packet */
		err = 0;

		len = MIN(total, MCONSOLE_MAX_DATA - 1);

		if(len == total) reply.more = more;
		else reply.more = 1;

		memcpy(reply.data, str, len);
		reply.data[len] = '\0';
		total -= len;
		str += len;
		reply.len = len + 1;

		len = sizeof(reply) + reply.len - sizeof(reply.data);

		n = sendto(req->originating_fd, &reply, len, 0,
			   (struct sockaddr *) req->origin, req->originlen);

		if(n < 0) return(-errno);
	} while(total > 0);
	return(0);
}

int mconsole_reply(struct mc_request *req, const char *str, int err, int more)
{
	return mconsole_reply_len(req, str, strlen(str), err, more);
}


int mconsole_unlink_socket(void)
{
	unlink(mconsole_socket_name);
	return 0;
}

static int notify_sock = -1;

int mconsole_notify(char *sock_name, int type, const void *data, int len)
{
	struct sockaddr_un target;
	struct mconsole_notify packet;
	int n, err = 0;

	lock_notify();
	if(notify_sock < 0){
		notify_sock = socket(PF_UNIX, SOCK_DGRAM, 0);
		if(notify_sock < 0){
			err = -errno;
			printk("mconsole_notify - socket failed, errno = %d\n",
			       err);
		}
	}
	unlock_notify();
	
	if(err)
		return(err);

	target.sun_family = AF_UNIX;
	strcpy(target.sun_path, sock_name);

	packet.magic = MCONSOLE_MAGIC;
	packet.version = MCONSOLE_VERSION;
	packet.type = type;
	len = (len > sizeof(packet.data)) ? sizeof(packet.data) : len;
	packet.len = len;
	memcpy(packet.data, data, len);

	err = 0;
	len = sizeof(packet) + packet.len - sizeof(packet.data);
	n = sendto(notify_sock, &packet, len, 0, (struct sockaddr *) &target, 
		   sizeof(target));
	if(n < 0){
		err = -errno;
		printk("mconsole_notify - sendto failed, errno = %d\n", errno);
	}
	return(err);
}

/*
 * Overrides for Emacs so that we follow Linus's tabbing style.
 * Emacs will notice this stuff at the end of the file and automatically
 * adjust the settings for this buffer only.  This must remain at the end
 * of the file.
 * ---------------------------------------------------------------------------
 * Local variables:
 * c-file-style: "linux"
 * End:
 */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org)
	3	* Copyright (C) 2001 - 2003 Jeff Dike (jdike@addtoit.com)
	4	* Licensed under the GPL
	5	*/
	6
	7	#include <stdio.h>
	8	#include <stdlib.h>
	9	#include <errno.h>
	10	#include <signal.h>
	11	#include <sys/socket.h>
	12	#include <sys/types.h>
	13	#include <sys/uio.h>
	14	#include <sys/un.h>
	15	#include <unistd.h>
	16	#include "user.h"
	17	#include "mconsole.h"
	18	#include "umid.h"
	19
	20	static struct mconsole_command commands[] = {
2d77f6fc JD	21	/* With uts namespaces, uts information becomes process-specific, so
	22	* we need a process context. If we try handling this in interrupt
	23	* context, we may hit an exiting process without a valid uts
	24	* namespace.
	25	*/
	26	{ "version", mconsole_version, MCONSOLE_PROC },
1da177e4 LT	27	{ "halt", mconsole_halt, MCONSOLE_PROC },
	28	{ "reboot", mconsole_reboot, MCONSOLE_PROC },
	29	{ "config", mconsole_config, MCONSOLE_PROC },
	30	{ "remove", mconsole_remove, MCONSOLE_PROC },
bd948057	31	{ "sysrq", mconsole_sysrq, MCONSOLE_INTR },
1da177e4 LT	32	{ "help", mconsole_help, MCONSOLE_INTR },
	33	{ "cad", mconsole_cad, MCONSOLE_INTR },
	34	{ "stop", mconsole_stop, MCONSOLE_PROC },
	35	{ "go", mconsole_go, MCONSOLE_INTR },
	36	{ "log", mconsole_log, MCONSOLE_INTR },
	37	{ "proc", mconsole_proc, MCONSOLE_PROC },
3eddddcf	38	{ "stack", mconsole_stack, MCONSOLE_INTR },
1da177e4 LT	39	};
	40
	41	/* Initialized in mconsole_init, which is an initcall */
	42	char mconsole_socket_name[256];
	43
	44	int mconsole_reply_v0(struct mc_request req, char reply)
	45	{
	46	struct iovec iov;
	47	struct msghdr msg;
	48
	49	iov.iov_base = reply;
	50	iov.iov_len = strlen(reply);
	51
	52	msg.msg_name = &(req->origin);
	53	msg.msg_namelen = req->originlen;
	54	msg.msg_iov = &iov;
	55	msg.msg_iovlen = 1;
	56	msg.msg_control = NULL;
	57	msg.msg_controllen = 0;
	58	msg.msg_flags = 0;
	59
	60	return sendmsg(req->originating_fd, &msg, 0);
	61	}
	62
	63	static struct mconsole_command mconsole_parse(struct mc_request req)
	64	{
	65	struct mconsole_command *cmd;
	66	int i;
	67
	68	for(i=0;i<sizeof(commands)/sizeof(commands[0]);i++){
	69	cmd = &commands[i];
	70	if(!strncmp(req->request.data, cmd->command,
	71	strlen(cmd->command))){
	72	return(cmd);
	73	}
	74	}
	75	return(NULL);
	76	}
	77
	78	#define MIN(a,b) ((a)<(b) ? (a):(b))
	79
	80	#define STRINGX(x) #x
	81	#define STRING(x) STRINGX(x)
	82
	83	int mconsole_get_request(int fd, struct mc_request *req)
	84	{
	85	int len;
	86
	87	req->originlen = sizeof(req->origin);
	88	req->len = recvfrom(fd, &req->request, sizeof(req->request), 0,
	89	(struct sockaddr *) req->origin, &req->originlen);
	90	if (req->len < 0)
	91	return 0;
	92
	93	req->originating_fd = fd;
	94
	95	if(req->request.magic != MCONSOLE_MAGIC){
	96	/* Unversioned request */
	97	len = MIN(sizeof(req->request.data) - 1,
	98	strlen((char *) &req->request));
	99	memmove(req->request.data, &req->request, len);
	100	req->request.data[len] = '\0';
	101
	102	req->request.magic = MCONSOLE_MAGIC;
103	req->request.version = 0;
104	req->request.len = len;
105
106	mconsole_reply_v0(req, "ERR Version 0 mconsole clients are "
107	"not supported by this driver");
108	return(0);
109	}
110
111	if(req->request.len >= MCONSOLE_MAX_DATA){
112	mconsole_reply(req, "Request too large", 1, 0);
113	return(0);
114	}
115	if(req->request.version != MCONSOLE_VERSION){
116	mconsole_reply(req, "This driver only supports version "
117	STRING(MCONSOLE_VERSION) " clients", 1, 0);
118	}
119
120	req->request.data[req->request.len] = '\0';
121	req->cmd = mconsole_parse(req);
122	if(req->cmd == NULL){
123	mconsole_reply(req, "Unknown command", 1, 0);
124	return(0);
125	}
126
127	return(1);
128	}
129
7b033e1f JD	130	int mconsole_reply_len(struct mc_request req, const char str, int total,
7b033e1f JD	131	int err, int more)
1da177e4 LT	132	{
1da177e4 LT	133	struct mconsole_reply reply;
7b033e1f	134	int len, n;
1da177e4	135
1da177e4 LT	136	do {
	137	reply.err = err;
	138
	139	/* err can only be true on the first packet */
	140	err = 0;
	141
	142	len = MIN(total, MCONSOLE_MAX_DATA - 1);
	143
	144	if(len == total) reply.more = more;
	145	else reply.more = 1;
	146
	147	memcpy(reply.data, str, len);
	148	reply.data[len] = '\0';
	149	total -= len;
	150	str += len;
	151	reply.len = len + 1;
	152
	153	len = sizeof(reply) + reply.len - sizeof(reply.data);
	154
	155	n = sendto(req->originating_fd, &reply, len, 0,
	156	(struct sockaddr *) req->origin, req->originlen);
	157
	158	if(n < 0) return(-errno);
	159	} while(total > 0);
	160	return(0);
	161	}
	162
7b033e1f JD	163	int mconsole_reply(struct mc_request req, const char str, int err, int more)
	164	{
	165	return mconsole_reply_len(req, str, strlen(str), err, more);
	166	}
	167
	168
1da177e4 LT	169	int mconsole_unlink_socket(void)
	170	{
	171	unlink(mconsole_socket_name);
	172	return 0;
	173	}
	174
	175	static int notify_sock = -1;
	176
	177	int mconsole_notify(char sock_name, int type, const void data, int len)
	178	{
	179	struct sockaddr_un target;
	180	struct mconsole_notify packet;
	181	int n, err = 0;
	182
	183	lock_notify();
	184	if(notify_sock < 0){
	185	notify_sock = socket(PF_UNIX, SOCK_DGRAM, 0);
	186	if(notify_sock < 0){
1da177e4	187	err = -errno;
b4fd310e JD	188	printk("mconsole_notify - socket failed, errno = %d\n",
b4fd310e JD	189	err);
1da177e4 LT	190	}
	191	}
	192	unlock_notify();
	193
	194	if(err)
	195	return(err);
	196
	197	target.sun_family = AF_UNIX;
	198	strcpy(target.sun_path, sock_name);
	199
	200	packet.magic = MCONSOLE_MAGIC;
	201	packet.version = MCONSOLE_VERSION;
	202	packet.type = type;
	203	len = (len > sizeof(packet.data)) ? sizeof(packet.data) : len;
	204	packet.len = len;
	205	memcpy(packet.data, data, len);
	206
	207	err = 0;
	208	len = sizeof(packet) + packet.len - sizeof(packet.data);
	209	n = sendto(notify_sock, &packet, len, 0, (struct sockaddr *) &target,
	210	sizeof(target));
	211	if(n < 0){
1da177e4	212	err = -errno;
b4fd310e	213	printk("mconsole_notify - sendto failed, errno = %d\n", errno);
1da177e4 LT	214	}
	215	return(err);
	216	}
	217
	218	/*
	219	* Overrides for Emacs so that we follow Linus's tabbing style.
	220	* Emacs will notice this stuff at the end of the file and automatically
	221	* adjust the settings for this buffer only. This must remain at the end
	222	* of the file.
	223	* ---------------------------------------------------------------------------
	224	* Local variables:
	225	* c-file-style: "linux"
	226	* End:
	227	*/