[qemu.git] / nbd.c

/*
 *  Copyright (C) 2005  Anthony Liguori <[email protected]>
 *
 *  Network Block Device
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; under version 2 of the License.
 *
 *  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.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA  02110-1301 USA
 */

#include "nbd.h"

#include <errno.h>
#include <string.h>
#ifndef _WIN32
#include <sys/ioctl.h>
#endif
#ifdef __sun__
#include <sys/ioccom.h>
#endif
#include <ctype.h>
#include <inttypes.h>

#include "qemu_socket.h"

//#define DEBUG_NBD

#ifdef DEBUG_NBD
#define TRACE(msg, ...) do { \
    LOG(msg, ## __VA_ARGS__); \
} while(0)
#else
#define TRACE(msg, ...) \
    do { } while (0)
#endif

#define LOG(msg, ...) do { \
    fprintf(stderr, "%s:%s():L%d: " msg "\n", \
            __FILE__, __FUNCTION__, __LINE__, ## __VA_ARGS__); \
} while(0)

/* This is all part of the "official" NBD API */

#define NBD_REQUEST_MAGIC       0x25609513
#define NBD_REPLY_MAGIC         0x67446698

#define NBD_SET_SOCK            _IO(0xab, 0)
#define NBD_SET_BLKSIZE         _IO(0xab, 1)
#define NBD_SET_SIZE            _IO(0xab, 2)
#define NBD_DO_IT               _IO(0xab, 3)
#define NBD_CLEAR_SOCK          _IO(0xab, 4)
#define NBD_CLEAR_QUE           _IO(0xab, 5)
#define NBD_PRINT_DEBUG	        _IO(0xab, 6)
#define NBD_SET_SIZE_BLOCKS	_IO(0xab, 7)
#define NBD_DISCONNECT          _IO(0xab, 8)

/* That's all folks */

#define read_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, true)
#define write_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, false)

size_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read)
{
    size_t offset = 0;

    while (offset < size) {
        ssize_t len;

        if (do_read) {
            len = recv(fd, buffer + offset, size - offset, 0);
        } else {
            len = send(fd, buffer + offset, size - offset, 0);
        }

        if (len == -1)
            errno = socket_error();

        /* recoverable error */
        if (len == -1 && (errno == EAGAIN || errno == EINTR)) {
            continue;
        }

        /* eof */
        if (len == 0) {
            break;
        }

        /* unrecoverable error */
        if (len == -1) {
            return 0;
        }

        offset += len;
    }

    return offset;
}

int tcp_socket_outgoing(const char *address, uint16_t port)
{
    int s;
    struct in_addr in;
    struct sockaddr_in addr;

    s = socket(PF_INET, SOCK_STREAM, 0);
    if (s == -1) {
        return -1;
    }

    if (inet_aton(address, &in) == 0) {
        struct hostent *ent;

        ent = gethostbyname(address);
        if (ent == NULL) {
            goto error;
        }

        memcpy(&in, ent->h_addr, sizeof(in));
    }

    addr.sin_family = AF_INET;
    addr.sin_port = htons(port);
    memcpy(&addr.sin_addr.s_addr, &in, sizeof(in));

    if (connect(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
        goto error;
    }

    return s;
error:
    closesocket(s);
    return -1;
}

int tcp_socket_incoming(const char *address, uint16_t port)
{
    int s;
    struct in_addr in;
    struct sockaddr_in addr;
    int opt;

    s = socket(PF_INET, SOCK_STREAM, 0);
    if (s == -1) {
        return -1;
    }

    if (inet_aton(address, &in) == 0) {
        struct hostent *ent;

        ent = gethostbyname(address);
        if (ent == NULL) {
            goto error;
        }

        memcpy(&in, ent->h_addr, sizeof(in));
    }

    addr.sin_family = AF_INET;
    addr.sin_port = htons(port);
    memcpy(&addr.sin_addr.s_addr, &in, sizeof(in));

    opt = 1;
    if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
                   (const void *) &opt, sizeof(opt)) == -1) {
        goto error;
    }

    if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
        goto error;
    }

    if (listen(s, 128) == -1) {
        goto error;
    }

    return s;
error:
    closesocket(s);
    return -1;
}

#ifndef _WIN32
int unix_socket_incoming(const char *path)
{
    int s;
    struct sockaddr_un addr;

    s = socket(PF_UNIX, SOCK_STREAM, 0);
    if (s == -1) {
        return -1;
    }

    memset(&addr, 0, sizeof(addr));
    addr.sun_family = AF_UNIX;
    pstrcpy(addr.sun_path, sizeof(addr.sun_path), path);

    if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
        goto error;
    }

    if (listen(s, 128) == -1) {
        goto error;
    }

    return s;
error:
    closesocket(s);
    return -1;
}

int unix_socket_outgoing(const char *path)
{
    int s;
    struct sockaddr_un addr;

    s = socket(PF_UNIX, SOCK_STREAM, 0);
    if (s == -1) {
        return -1;
    }

    memset(&addr, 0, sizeof(addr));
    addr.sun_family = AF_UNIX;
    pstrcpy(addr.sun_path, sizeof(addr.sun_path), path);

    if (connect(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
        goto error;
    }

    return s;
error:
    closesocket(s);
    return -1;
}
#else
int unix_socket_incoming(const char *path)
{
    errno = ENOTSUP;
    return -1;
}

int unix_socket_outgoing(const char *path)
{
    errno = ENOTSUP;
    return -1;
}
#endif


/* Basic flow

   Server         Client

   Negotiate
                  Request
   Response
                  Request
   Response
                  ...
   ...
                  Request (type == 2)
*/

int nbd_negotiate(int csock, off_t size)
{
	char buf[8 + 8 + 8 + 128];

	/* Negotiate
	   [ 0 ..   7]   passwd   ("NBDMAGIC")
	   [ 8 ..  15]   magic    (0x00420281861253)
	   [16 ..  23]   size
	   [24 .. 151]   reserved (0)
	 */

	TRACE("Beginning negotiation.");
	memcpy(buf, "NBDMAGIC", 8);
	cpu_to_be64w((uint64_t*)(buf + 8), 0x00420281861253LL);
	cpu_to_be64w((uint64_t*)(buf + 16), size);
	memset(buf + 24, 0, 128);

	if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
		LOG("write failed");
		errno = EINVAL;
		return -1;
	}

	TRACE("Negotation succeeded.");

	return 0;
}

int nbd_receive_negotiate(int csock, off_t *size, size_t *blocksize)
{
	char buf[8 + 8 + 8 + 128];
	uint64_t magic;

	TRACE("Receiving negotation.");

	if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
		LOG("read failed");
		errno = EINVAL;
		return -1;
	}

	magic = be64_to_cpup((uint64_t*)(buf + 8));
	*size = be64_to_cpup((uint64_t*)(buf + 16));
	*blocksize = 1024;

	TRACE("Magic is %c%c%c%c%c%c%c%c",
	      qemu_isprint(buf[0]) ? buf[0] : '.',
	      qemu_isprint(buf[1]) ? buf[1] : '.',
	      qemu_isprint(buf[2]) ? buf[2] : '.',
	      qemu_isprint(buf[3]) ? buf[3] : '.',
	      qemu_isprint(buf[4]) ? buf[4] : '.',
	      qemu_isprint(buf[5]) ? buf[5] : '.',
	      qemu_isprint(buf[6]) ? buf[6] : '.',
	      qemu_isprint(buf[7]) ? buf[7] : '.');
	TRACE("Magic is 0x%" PRIx64, magic);
	TRACE("Size is %" PRIu64, *size);

	if (memcmp(buf, "NBDMAGIC", 8) != 0) {
		LOG("Invalid magic received");
		errno = EINVAL;
		return -1;
	}

	TRACE("Checking magic");

	if (magic != 0x00420281861253LL) {
		LOG("Bad magic received");
		errno = EINVAL;
		return -1;
	}
        return 0;
}

#ifndef _WIN32
int nbd_init(int fd, int csock, off_t size, size_t blocksize)
{
	TRACE("Setting block size to %lu", (unsigned long)blocksize);

	if (ioctl(fd, NBD_SET_BLKSIZE, blocksize) == -1) {
		int serrno = errno;
		LOG("Failed setting NBD block size");
		errno = serrno;
		return -1;
	}

	TRACE("Setting size to %llu block(s)",
	      (unsigned long long)(size / blocksize));

	if (ioctl(fd, NBD_SET_SIZE_BLOCKS, size / blocksize) == -1) {
		int serrno = errno;
		LOG("Failed setting size (in blocks)");
		errno = serrno;
		return -1;
	}

	TRACE("Clearing NBD socket");

	if (ioctl(fd, NBD_CLEAR_SOCK) == -1) {
		int serrno = errno;
		LOG("Failed clearing NBD socket");
		errno = serrno;
		return -1;
	}

	TRACE("Setting NBD socket");

	if (ioctl(fd, NBD_SET_SOCK, csock) == -1) {
		int serrno = errno;
		LOG("Failed to set NBD socket");
		errno = serrno;
		return -1;
	}

	TRACE("Negotiation ended");

	return 0;
}

int nbd_disconnect(int fd)
{
	ioctl(fd, NBD_CLEAR_QUE);
	ioctl(fd, NBD_DISCONNECT);
	ioctl(fd, NBD_CLEAR_SOCK);
	return 0;
}

int nbd_client(int fd, int csock)
{
	int ret;
	int serrno;

	TRACE("Doing NBD loop");

	ret = ioctl(fd, NBD_DO_IT);
	serrno = errno;

	TRACE("NBD loop returned %d: %s", ret, strerror(serrno));

	TRACE("Clearing NBD queue");
	ioctl(fd, NBD_CLEAR_QUE);

	TRACE("Clearing NBD socket");
	ioctl(fd, NBD_CLEAR_SOCK);

	errno = serrno;
	return ret;
}
#else
int nbd_init(int fd, int csock, off_t size, size_t blocksize)
{
    errno = ENOTSUP;
    return -1;
}

int nbd_disconnect(int fd)
{
    errno = ENOTSUP;
    return -1;
}

int nbd_client(int fd, int csock)
{
    errno = ENOTSUP;
    return -1;
}
#endif

int nbd_send_request(int csock, struct nbd_request *request)
{
	uint8_t buf[4 + 4 + 8 + 8 + 4];

	cpu_to_be32w((uint32_t*)buf, NBD_REQUEST_MAGIC);
	cpu_to_be32w((uint32_t*)(buf + 4), request->type);
	cpu_to_be64w((uint64_t*)(buf + 8), request->handle);
	cpu_to_be64w((uint64_t*)(buf + 16), request->from);
	cpu_to_be32w((uint32_t*)(buf + 24), request->len);

	TRACE("Sending request to client");

	if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
		LOG("writing to socket failed");
		errno = EINVAL;
		return -1;
	}
	return 0;
}


static int nbd_receive_request(int csock, struct nbd_request *request)
{
	uint8_t buf[4 + 4 + 8 + 8 + 4];
	uint32_t magic;

	if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
		LOG("read failed");
		errno = EINVAL;
		return -1;
	}

	/* Request
	   [ 0 ..  3]   magic   (NBD_REQUEST_MAGIC)
	   [ 4 ..  7]   type    (0 == READ, 1 == WRITE)
	   [ 8 .. 15]   handle
	   [16 .. 23]   from
	   [24 .. 27]   len
	 */

	magic = be32_to_cpup((uint32_t*)buf);
	request->type  = be32_to_cpup((uint32_t*)(buf + 4));
	request->handle = be64_to_cpup((uint64_t*)(buf + 8));
	request->from  = be64_to_cpup((uint64_t*)(buf + 16));
	request->len   = be32_to_cpup((uint32_t*)(buf + 24));

	TRACE("Got request: "
	      "{ magic = 0x%x, .type = %d, from = %" PRIu64" , len = %u }",
	      magic, request->type, request->from, request->len);

	if (magic != NBD_REQUEST_MAGIC) {
		LOG("invalid magic (got 0x%x)", magic);
		errno = EINVAL;
		return -1;
	}
	return 0;
}

int nbd_receive_reply(int csock, struct nbd_reply *reply)
{
	uint8_t buf[4 + 4 + 8];
	uint32_t magic;

	memset(buf, 0xAA, sizeof(buf));

	if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
		LOG("read failed");
		errno = EINVAL;
		return -1;
	}

	/* Reply
	   [ 0 ..  3]    magic   (NBD_REPLY_MAGIC)
	   [ 4 ..  7]    error   (0 == no error)
	   [ 7 .. 15]    handle
	 */

	magic = be32_to_cpup((uint32_t*)buf);
	reply->error  = be32_to_cpup((uint32_t*)(buf + 4));
	reply->handle = be64_to_cpup((uint64_t*)(buf + 8));

	TRACE("Got reply: "
	      "{ magic = 0x%x, .error = %d, handle = %" PRIu64" }",
	      magic, reply->error, reply->handle);

	if (magic != NBD_REPLY_MAGIC) {
		LOG("invalid magic (got 0x%x)", magic);
		errno = EINVAL;
		return -1;
	}
	return 0;
}

static int nbd_send_reply(int csock, struct nbd_reply *reply)
{
	uint8_t buf[4 + 4 + 8];

	/* Reply
	   [ 0 ..  3]    magic   (NBD_REPLY_MAGIC)
	   [ 4 ..  7]    error   (0 == no error)
	   [ 7 .. 15]    handle
	 */
	cpu_to_be32w((uint32_t*)buf, NBD_REPLY_MAGIC);
	cpu_to_be32w((uint32_t*)(buf + 4), reply->error);
	cpu_to_be64w((uint64_t*)(buf + 8), reply->handle);

	TRACE("Sending response to client");

	if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
		LOG("writing to socket failed");
		errno = EINVAL;
		return -1;
	}
	return 0;
}

int nbd_trip(BlockDriverState *bs, int csock, off_t size, uint64_t dev_offset,
             off_t *offset, bool readonly, uint8_t *data, int data_size)
{
	struct nbd_request request;
	struct nbd_reply reply;

	TRACE("Reading request.");

	if (nbd_receive_request(csock, &request) == -1)
		return -1;

	if (request.len > data_size) {
		LOG("len (%u) is larger than max len (%u)",
		    request.len, data_size);
		errno = EINVAL;
		return -1;
	}

	if ((request.from + request.len) < request.from) {
		LOG("integer overflow detected! "
		    "you're probably being attacked");
		errno = EINVAL;
		return -1;
	}

	if ((request.from + request.len) > size) {
	        LOG("From: %" PRIu64 ", Len: %u, Size: %" PRIu64
		    ", Offset: %" PRIu64 "\n",
                    request.from, request.len, (uint64_t)size, dev_offset);
		LOG("requested operation past EOF--bad client?");
		errno = EINVAL;
		return -1;
	}

	TRACE("Decoding type");

	reply.handle = request.handle;
	reply.error = 0;

	switch (request.type) {
	case NBD_CMD_READ:
		TRACE("Request type is READ");

		if (bdrv_read(bs, (request.from + dev_offset) / 512, data,
			      request.len / 512) == -1) {
			LOG("reading from file failed");
			errno = EINVAL;
			return -1;
		}
		*offset += request.len;

		TRACE("Read %u byte(s)", request.len);

		if (nbd_send_reply(csock, &reply) == -1)
			return -1;

		TRACE("Sending data to client");

		if (write_sync(csock, data, request.len) != request.len) {
			LOG("writing to socket failed");
			errno = EINVAL;
			return -1;
		}
		break;
	case NBD_CMD_WRITE:
		TRACE("Request type is WRITE");

		TRACE("Reading %u byte(s)", request.len);

		if (read_sync(csock, data, request.len) != request.len) {
			LOG("reading from socket failed");
			errno = EINVAL;
			return -1;
		}

		if (readonly) {
			TRACE("Server is read-only, return error");
			reply.error = 1;
		} else {
			TRACE("Writing to device");

			if (bdrv_write(bs, (request.from + dev_offset) / 512,
				       data, request.len / 512) == -1) {
				LOG("writing to file failed");
				errno = EINVAL;
				return -1;
			}

			*offset += request.len;
		}

		if (nbd_send_reply(csock, &reply) == -1)
			return -1;
		break;
	case NBD_CMD_DISC:
		TRACE("Request type is DISCONNECT");
		errno = 0;
		return 1;
	default:
		LOG("invalid request type (%u) received", request.type);
		errno = EINVAL;
		return -1;
	}

	TRACE("Request/Reply complete");

	return 0;
}
Commit	Line	Data
75818250	1	/*
7a5ca864 FB	2	* Copyright (C) 2005 Anthony Liguori <[email protected]>
	3	*
	4	* Network Block Device
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; under version 2 of the License.
	9	*
	10	* This program is distributed in the hope that it will be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	* GNU General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
	16	* along with this program; if not, write to the Free Software
fad6cb1a	17	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA
75818250	18	*/
7a5ca864 FB	19
	20	#include "nbd.h"
	21
	22	#include <errno.h>
	23	#include <string.h>
03ff3ca3	24	#ifndef _WIN32
7a5ca864	25	#include <sys/ioctl.h>
03ff3ca3	26	#endif
7e00eb9b AL	27	#ifdef __sun__
	28	#include <sys/ioccom.h>
	29	#endif
7a5ca864 FB	30	#include <ctype.h>
7a5ca864 FB	31	#include <inttypes.h>
75818250	32
03ff3ca3 AL	33	#include "qemu_socket.h"
	34
	35	//#define DEBUG_NBD
	36
	37	#ifdef DEBUG_NBD
75818250	38	#define TRACE(msg, ...) do { \
03ff3ca3	39	LOG(msg, ## __VA_ARGS__); \
75818250	40	} while(0)
03ff3ca3 AL	41	#else
	42	#define TRACE(msg, ...) \
	43	do { } while (0)
	44	#endif
7a5ca864 FB	45
	46	#define LOG(msg, ...) do { \
	47	fprintf(stderr, "%s:%s():L%d: " msg "\n", \
	48	__FILE__, __FUNCTION__, __LINE__, ## __VA_ARGS__); \
	49	} while(0)
	50
7a5ca864 FB	51	/* This is all part of the "official" NBD API */
	52
	53	#define NBD_REQUEST_MAGIC 0x25609513
	54	#define NBD_REPLY_MAGIC 0x67446698
	55
	56	#define NBD_SET_SOCK _IO(0xab, 0)
	57	#define NBD_SET_BLKSIZE _IO(0xab, 1)
	58	#define NBD_SET_SIZE _IO(0xab, 2)
	59	#define NBD_DO_IT _IO(0xab, 3)
	60	#define NBD_CLEAR_SOCK _IO(0xab, 4)
	61	#define NBD_CLEAR_QUE _IO(0xab, 5)
	62	#define NBD_PRINT_DEBUG _IO(0xab, 6)
	63	#define NBD_SET_SIZE_BLOCKS _IO(0xab, 7)
	64	#define NBD_DISCONNECT _IO(0xab, 8)
	65
	66	/* That's all folks */
	67
75818250 TS	68	#define read_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, true)
75818250 TS	69	#define write_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, false)
7a5ca864	70
75818250	71	size_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read)
7a5ca864 FB	72	{
	73	size_t offset = 0;
	74
	75	while (offset < size) {
	76	ssize_t len;
	77
	78	if (do_read) {
03ff3ca3	79	len = recv(fd, buffer + offset, size - offset, 0);
7a5ca864	80	} else {
03ff3ca3	81	len = send(fd, buffer + offset, size - offset, 0);
7a5ca864 FB	82	}
7a5ca864 FB	83
03ff3ca3 AL	84	if (len == -1)
	85	errno = socket_error();
	86
7a5ca864	87	/* recoverable error */
75818250	88	if (len == -1 && (errno == EAGAIN \|\| errno == EINTR)) {
7a5ca864 FB	89	continue;
	90	}
	91
	92	/* eof */
	93	if (len == 0) {
	94	break;
	95	}
	96
	97	/* unrecoverable error */
	98	if (len == -1) {
	99	return 0;
	100	}
	101
	102	offset += len;
	103	}
	104
	105	return offset;
	106	}
	107
75818250	108	int tcp_socket_outgoing(const char *address, uint16_t port)
7a5ca864 FB	109	{
	110	int s;
	111	struct in_addr in;
	112	struct sockaddr_in addr;
7a5ca864 FB	113
	114	s = socket(PF_INET, SOCK_STREAM, 0);
	115	if (s == -1) {
	116	return -1;
	117	}
	118
	119	if (inet_aton(address, &in) == 0) {
	120	struct hostent *ent;
	121
	122	ent = gethostbyname(address);
	123	if (ent == NULL) {
	124	goto error;
	125	}
	126
	127	memcpy(&in, ent->h_addr, sizeof(in));
	128	}
	129
	130	addr.sin_family = AF_INET;
	131	addr.sin_port = htons(port);
	132	memcpy(&addr.sin_addr.s_addr, &in, sizeof(in));
	133
	134	if (connect(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
	135	goto error;
	136	}
	137
	138	return s;
	139	error:
03ff3ca3	140	closesocket(s);
7a5ca864 FB	141	return -1;
	142	}
	143
	144	int tcp_socket_incoming(const char *address, uint16_t port)
	145	{
	146	int s;
	147	struct in_addr in;
	148	struct sockaddr_in addr;
7a5ca864 FB	149	int opt;
	150
	151	s = socket(PF_INET, SOCK_STREAM, 0);
	152	if (s == -1) {
	153	return -1;
	154	}
	155
	156	if (inet_aton(address, &in) == 0) {
	157	struct hostent *ent;
	158
	159	ent = gethostbyname(address);
	160	if (ent == NULL) {
	161	goto error;
	162	}
	163
	164	memcpy(&in, ent->h_addr, sizeof(in));
	165	}
	166
	167	addr.sin_family = AF_INET;
	168	addr.sin_port = htons(port);
	169	memcpy(&addr.sin_addr.s_addr, &in, sizeof(in));
	170
	171	opt = 1;
0a656f5f	172	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
0a656f5f	173	(const void *) &opt, sizeof(opt)) == -1) {
7a5ca864 FB	174	goto error;
	175	}
	176
	177	if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
	178	goto error;
	179	}
	180
	181	if (listen(s, 128) == -1) {
	182	goto error;
	183	}
	184
	185	return s;
	186	error:
03ff3ca3	187	closesocket(s);
7a5ca864 FB	188	return -1;
	189	}
	190
03ff3ca3	191	#ifndef _WIN32
cd831bd7 TS	192	int unix_socket_incoming(const char *path)
	193	{
	194	int s;
	195	struct sockaddr_un addr;
cd831bd7 TS	196
	197	s = socket(PF_UNIX, SOCK_STREAM, 0);
	198	if (s == -1) {
	199	return -1;
	200	}
	201
	202	memset(&addr, 0, sizeof(addr));
	203	addr.sun_family = AF_UNIX;
	204	pstrcpy(addr.sun_path, sizeof(addr.sun_path), path);
	205
	206	if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
	207	goto error;
	208	}
	209
	210	if (listen(s, 128) == -1) {
	211	goto error;
	212	}
	213
	214	return s;
	215	error:
03ff3ca3	216	closesocket(s);
cd831bd7 TS	217	return -1;
	218	}
	219
	220	int unix_socket_outgoing(const char *path)
	221	{
	222	int s;
	223	struct sockaddr_un addr;
cd831bd7 TS	224
	225	s = socket(PF_UNIX, SOCK_STREAM, 0);
	226	if (s == -1) {
	227	return -1;
	228	}
	229
	230	memset(&addr, 0, sizeof(addr));
	231	addr.sun_family = AF_UNIX;
	232	pstrcpy(addr.sun_path, sizeof(addr.sun_path), path);
	233
	234	if (connect(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
	235	goto error;
	236	}
	237
	238	return s;
	239	error:
03ff3ca3 AL	240	closesocket(s);
	241	return -1;
	242	}
	243	#else
	244	int unix_socket_incoming(const char *path)
	245	{
	246	errno = ENOTSUP;
cd831bd7 TS	247	return -1;
	248	}
	249
03ff3ca3 AL	250	int unix_socket_outgoing(const char *path)
	251	{
	252	errno = ENOTSUP;
	253	return -1;
	254	}
	255	#endif
	256
cd831bd7	257
7a5ca864 FB	258	/* Basic flow
	259
	260	Server Client
	261
	262	Negotiate
	263	Request
	264	Response
	265	Request
	266	Response
	267	...
	268	...
	269	Request (type == 2)
	270	*/
	271
27982661	272	int nbd_negotiate(int csock, off_t size)
7a5ca864 FB	273	{
	274	char buf[8 + 8 + 8 + 128];
	275
	276	/* Negotiate
	277	[ 0 .. 7] passwd ("NBDMAGIC")
	278	[ 8 .. 15] magic (0x00420281861253)
	279	[16 .. 23] size
	280	[24 .. 151] reserved (0)
	281	*/
	282
	283	TRACE("Beginning negotiation.");
	284	memcpy(buf, "NBDMAGIC", 8);
	285	cpu_to_be64w((uint64_t*)(buf + 8), 0x00420281861253LL);
	286	cpu_to_be64w((uint64_t*)(buf + 16), size);
	287	memset(buf + 24, 0, 128);
	288
	289	if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
	290	LOG("write failed");
	291	errno = EINVAL;
	292	return -1;
	293	}
	294
	295	TRACE("Negotation succeeded.");
	296
	297	return 0;
	298	}
	299
cd831bd7	300	int nbd_receive_negotiate(int csock, off_t size, size_t blocksize)
7a5ca864 FB	301	{
	302	char buf[8 + 8 + 8 + 128];
	303	uint64_t magic;
7a5ca864 FB	304
	305	TRACE("Receiving negotation.");
	306
	307	if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
	308	LOG("read failed");
	309	errno = EINVAL;
	310	return -1;
	311	}
	312
	313	magic = be64_to_cpup((uint64_t*)(buf + 8));
cd831bd7 TS	314	size = be64_to_cpup((uint64_t)(buf + 16));
cd831bd7 TS	315	*blocksize = 1024;
7a5ca864 FB	316
7a5ca864 FB	317	TRACE("Magic is %c%c%c%c%c%c%c%c",
47398b9c BS	318	qemu_isprint(buf[0]) ? buf[0] : '.',
	319	qemu_isprint(buf[1]) ? buf[1] : '.',
	320	qemu_isprint(buf[2]) ? buf[2] : '.',
	321	qemu_isprint(buf[3]) ? buf[3] : '.',
	322	qemu_isprint(buf[4]) ? buf[4] : '.',
	323	qemu_isprint(buf[5]) ? buf[5] : '.',
	324	qemu_isprint(buf[6]) ? buf[6] : '.',
	325	qemu_isprint(buf[7]) ? buf[7] : '.');
7a5ca864	326	TRACE("Magic is 0x%" PRIx64, magic);
cd831bd7	327	TRACE("Size is %" PRIu64, *size);
7a5ca864 FB	328
	329	if (memcmp(buf, "NBDMAGIC", 8) != 0) {
	330	LOG("Invalid magic received");
	331	errno = EINVAL;
	332	return -1;
	333	}
	334
	335	TRACE("Checking magic");
	336
	337	if (magic != 0x00420281861253LL) {
	338	LOG("Bad magic received");
	339	errno = EINVAL;
	340	return -1;
	341	}
cd831bd7 TS	342	return 0;
cd831bd7 TS	343	}
7a5ca864	344
03ff3ca3	345	#ifndef _WIN32
cd831bd7 TS	346	int nbd_init(int fd, int csock, off_t size, size_t blocksize)
cd831bd7 TS	347	{
7a5ca864 FB	348	TRACE("Setting block size to %lu", (unsigned long)blocksize);
	349
	350	if (ioctl(fd, NBD_SET_BLKSIZE, blocksize) == -1) {
	351	int serrno = errno;
	352	LOG("Failed setting NBD block size");
	353	errno = serrno;
	354	return -1;
	355	}
	356
	357	TRACE("Setting size to %llu block(s)",
	358	(unsigned long long)(size / blocksize));
	359
	360	if (ioctl(fd, NBD_SET_SIZE_BLOCKS, size / blocksize) == -1) {
	361	int serrno = errno;
	362	LOG("Failed setting size (in blocks)");
	363	errno = serrno;
	364	return -1;
	365	}
	366
	367	TRACE("Clearing NBD socket");
	368
	369	if (ioctl(fd, NBD_CLEAR_SOCK) == -1) {
	370	int serrno = errno;
	371	LOG("Failed clearing NBD socket");
	372	errno = serrno;
	373	return -1;
	374	}
	375
	376	TRACE("Setting NBD socket");
	377
	378	if (ioctl(fd, NBD_SET_SOCK, csock) == -1) {
	379	int serrno = errno;
	380	LOG("Failed to set NBD socket");
	381	errno = serrno;
	382	return -1;
	383	}
	384
	385	TRACE("Negotiation ended");
	386
	387	return 0;
	388	}
	389
	390	int nbd_disconnect(int fd)
	391	{
	392	ioctl(fd, NBD_CLEAR_QUE);
	393	ioctl(fd, NBD_DISCONNECT);
	394	ioctl(fd, NBD_CLEAR_SOCK);
	395	return 0;
	396	}
	397
	398	int nbd_client(int fd, int csock)
	399	{
	400	int ret;
	401	int serrno;
	402
	403	TRACE("Doing NBD loop");
	404
	405	ret = ioctl(fd, NBD_DO_IT);
	406	serrno = errno;
	407
	408	TRACE("NBD loop returned %d: %s", ret, strerror(serrno));
	409
	410	TRACE("Clearing NBD queue");
	411	ioctl(fd, NBD_CLEAR_QUE);
412
413	TRACE("Clearing NBD socket");
414	ioctl(fd, NBD_CLEAR_SOCK);
415
416	errno = serrno;
417	return ret;
418	}
03ff3ca3 AL	419	#else
	420	int nbd_init(int fd, int csock, off_t size, size_t blocksize)
	421	{
	422	errno = ENOTSUP;
	423	return -1;
	424	}
	425
	426	int nbd_disconnect(int fd)
	427	{
	428	errno = ENOTSUP;
	429	return -1;
	430	}
	431
	432	int nbd_client(int fd, int csock)
	433	{
	434	errno = ENOTSUP;
	435	return -1;
	436	}
	437	#endif
7a5ca864	438
75818250	439	int nbd_send_request(int csock, struct nbd_request *request)
7a5ca864	440	{
7a5ca864	441	uint8_t buf[4 + 4 + 8 + 8 + 4];
7a5ca864	442
75818250 TS	443	cpu_to_be32w((uint32_t*)buf, NBD_REQUEST_MAGIC);
	444	cpu_to_be32w((uint32_t*)(buf + 4), request->type);
	445	cpu_to_be64w((uint64_t*)(buf + 8), request->handle);
	446	cpu_to_be64w((uint64_t*)(buf + 16), request->from);
	447	cpu_to_be32w((uint32_t*)(buf + 24), request->len);
	448
	449	TRACE("Sending request to client");
	450
	451	if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
	452	LOG("writing to socket failed");
	453	errno = EINVAL;
	454	return -1;
	455	}
	456	return 0;
	457	}
	458
	459
	460	static int nbd_receive_request(int csock, struct nbd_request *request)
	461	{
	462	uint8_t buf[4 + 4 + 8 + 8 + 4];
	463	uint32_t magic;
7a5ca864 FB	464
	465	if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
	466	LOG("read failed");
	467	errno = EINVAL;
	468	return -1;
	469	}
	470
	471	/* Request
75818250 TS	472	[ 0 .. 3] magic (NBD_REQUEST_MAGIC)
	473	[ 4 .. 7] type (0 == READ, 1 == WRITE)
	474	[ 8 .. 15] handle
	475	[16 .. 23] from
	476	[24 .. 27] len
7a5ca864 FB	477	*/
	478
	479	magic = be32_to_cpup((uint32_t*)buf);
75818250 TS	480	request->type = be32_to_cpup((uint32_t*)(buf + 4));
	481	request->handle = be64_to_cpup((uint64_t*)(buf + 8));
	482	request->from = be64_to_cpup((uint64_t*)(buf + 16));
	483	request->len = be32_to_cpup((uint32_t*)(buf + 24));
7a5ca864 FB	484
	485	TRACE("Got request: "
	486	"{ magic = 0x%x, .type = %d, from = %" PRIu64" , len = %u }",
75818250	487	magic, request->type, request->from, request->len);
7a5ca864 FB	488
	489	if (magic != NBD_REQUEST_MAGIC) {
	490	LOG("invalid magic (got 0x%x)", magic);
	491	errno = EINVAL;
	492	return -1;
	493	}
d94888e3	494	return 0;
75818250 TS	495	}
	496
	497	int nbd_receive_reply(int csock, struct nbd_reply *reply)
	498	{
	499	uint8_t buf[4 + 4 + 8];
	500	uint32_t magic;
	501
	502	memset(buf, 0xAA, sizeof(buf));
	503
	504	if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
	505	LOG("read failed");
	506	errno = EINVAL;
	507	return -1;
	508	}
	509
	510	/* Reply
	511	[ 0 .. 3] magic (NBD_REPLY_MAGIC)
	512	[ 4 .. 7] error (0 == no error)
	513	[ 7 .. 15] handle
	514	*/
	515
	516	magic = be32_to_cpup((uint32_t*)buf);
	517	reply->error = be32_to_cpup((uint32_t*)(buf + 4));
	518	reply->handle = be64_to_cpup((uint64_t*)(buf + 8));
	519
	520	TRACE("Got reply: "
	521	"{ magic = 0x%x, .error = %d, handle = %" PRIu64" }",
	522	magic, reply->error, reply->handle);
	523
	524	if (magic != NBD_REPLY_MAGIC) {
	525	LOG("invalid magic (got 0x%x)", magic);
	526	errno = EINVAL;
	527	return -1;
	528	}
	529	return 0;
	530	}
	531
	532	static int nbd_send_reply(int csock, struct nbd_reply *reply)
	533	{
	534	uint8_t buf[4 + 4 + 8];
	535
	536	/* Reply
	537	[ 0 .. 3] magic (NBD_REPLY_MAGIC)
	538	[ 4 .. 7] error (0 == no error)
	539	[ 7 .. 15] handle
	540	*/
	541	cpu_to_be32w((uint32_t*)buf, NBD_REPLY_MAGIC);
	542	cpu_to_be32w((uint32_t*)(buf + 4), reply->error);
	543	cpu_to_be64w((uint64_t*)(buf + 8), reply->handle);
	544
	545	TRACE("Sending response to client");
	546
	547	if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
	548	LOG("writing to socket failed");
	549	errno = EINVAL;
	550	return -1;
	551	}
	552	return 0;
	553	}
7a5ca864	554
75818250 TS	555	int nbd_trip(BlockDriverState *bs, int csock, off_t size, uint64_t dev_offset,
	556	off_t offset, bool readonly, uint8_t data, int data_size)
	557	{
	558	struct nbd_request request;
	559	struct nbd_reply reply;
	560
	561	TRACE("Reading request.");
	562
	563	if (nbd_receive_request(csock, &request) == -1)
	564	return -1;
	565
	566	if (request.len > data_size) {
2f726488	567	LOG("len (%u) is larger than max len (%u)",
75818250	568	request.len, data_size);
7a5ca864 FB	569	errno = EINVAL;
	570	return -1;
	571	}
	572
75818250	573	if ((request.from + request.len) < request.from) {
7a5ca864 FB	574	LOG("integer overflow detected! "
	575	"you're probably being attacked");
	576	errno = EINVAL;
	577	return -1;
	578	}
	579
75818250	580	if ((request.from + request.len) > size) {
7a5ca864 FB	581	LOG("From: %" PRIu64 ", Len: %u, Size: %" PRIu64
7a5ca864 FB	582	", Offset: %" PRIu64 "\n",
b9e82a59	583	request.from, request.len, (uint64_t)size, dev_offset);
7a5ca864 FB	584	LOG("requested operation past EOF--bad client?");
	585	errno = EINVAL;
	586	return -1;
	587	}
	588
7a5ca864 FB	589	TRACE("Decoding type");
7a5ca864 FB	590
75818250 TS	591	reply.handle = request.handle;
	592	reply.error = 0;
	593
	594	switch (request.type) {
	595	case NBD_CMD_READ:
7a5ca864 FB	596	TRACE("Request type is READ");
7a5ca864 FB	597
75818250 TS	598	if (bdrv_read(bs, (request.from + dev_offset) / 512, data,
75818250 TS	599	request.len / 512) == -1) {
7a5ca864 FB	600	LOG("reading from file failed");
	601	errno = EINVAL;
	602	return -1;
	603	}
75818250	604	*offset += request.len;
7a5ca864	605
75818250	606	TRACE("Read %u byte(s)", request.len);
7a5ca864	607
75818250	608	if (nbd_send_reply(csock, &reply) == -1)
7a5ca864	609	return -1;
7a5ca864 FB	610
	611	TRACE("Sending data to client");
	612
75818250	613	if (write_sync(csock, data, request.len) != request.len) {
7a5ca864 FB	614	LOG("writing to socket failed");
	615	errno = EINVAL;
	616	return -1;
	617	}
	618	break;
75818250	619	case NBD_CMD_WRITE:
7a5ca864 FB	620	TRACE("Request type is WRITE");
7a5ca864 FB	621
75818250	622	TRACE("Reading %u byte(s)", request.len);
7a5ca864	623
75818250	624	if (read_sync(csock, data, request.len) != request.len) {
7a5ca864 FB	625	LOG("reading from socket failed");
	626	errno = EINVAL;
	627	return -1;
	628	}
	629
	630	if (readonly) {
	631	TRACE("Server is read-only, return error");
75818250	632	reply.error = 1;
7a5ca864 FB	633	} else {
	634	TRACE("Writing to device");
	635
75818250 TS	636	if (bdrv_write(bs, (request.from + dev_offset) / 512,
75818250 TS	637	data, request.len / 512) == -1) {
7a5ca864 FB	638	LOG("writing to file failed");
	639	errno = EINVAL;
	640	return -1;
	641	}
	642
75818250	643	*offset += request.len;
7a5ca864 FB	644	}
7a5ca864 FB	645
75818250	646	if (nbd_send_reply(csock, &reply) == -1)
7a5ca864	647	return -1;
7a5ca864	648	break;
75818250	649	case NBD_CMD_DISC:
7a5ca864 FB	650	TRACE("Request type is DISCONNECT");
	651	errno = 0;
	652	return 1;
	653	default:
75818250	654	LOG("invalid request type (%u) received", request.type);
7a5ca864 FB	655	errno = EINVAL;
	656	return -1;
	657	}
	658
	659	TRACE("Request/Reply complete");
	660
	661	return 0;
	662	}