[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, see <http://www.gnu.org/licenses/>.
 */

#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)

#define NBD_OPT_EXPORT_NAME	(1 << 0)

/* 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, const char *name, uint32_t *flags,
                          off_t *size, size_t *blocksize)
{
	char buf[256];
	uint64_t magic, s;
	uint16_t tmp;

	TRACE("Receiving negotation.");

	if (read_sync(csock, buf, 8) != 8) {
		LOG("read failed");
		errno = EINVAL;
		return -1;
	}

	buf[8] = '\0';
	if (strlen(buf) == 0) {
		LOG("server connection closed");
		errno = EINVAL;
		return -1;
	}

	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] : '.');

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

	if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) {
		LOG("read failed");
		errno = EINVAL;
		return -1;
	}
	magic = be64_to_cpu(magic);
	TRACE("Magic is 0x%" PRIx64, magic);

	if (name) {
		uint32_t reserved = 0;
		uint32_t opt;
		uint32_t namesize;

		TRACE("Checking magic (opts_magic)");
		if (magic != 0x49484156454F5054LL) {
			LOG("Bad magic received");
			errno = EINVAL;
			return -1;
		}
		if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) {
			LOG("flags read failed");
			errno = EINVAL;
			return -1;
		}
		*flags = be16_to_cpu(tmp) << 16;
		/* reserved for future use */
		if (write_sync(csock, &reserved, sizeof(reserved)) !=
		    sizeof(reserved)) {
			LOG("write failed (reserved)");
			errno = EINVAL;
			return -1;
		}
		/* write the export name */
		magic = cpu_to_be64(magic);
		if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) {
			LOG("write failed (magic)");
			errno = EINVAL;
			return -1;
		}
		opt = cpu_to_be32(NBD_OPT_EXPORT_NAME);
		if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) {
			LOG("write failed (opt)");
			errno = EINVAL;
			return -1;
		}
		namesize = cpu_to_be32(strlen(name));
		if (write_sync(csock, &namesize, sizeof(namesize)) !=
		    sizeof(namesize)) {
			LOG("write failed (namesize)");
			errno = EINVAL;
			return -1;
		}
		if (write_sync(csock, (char*)name, strlen(name)) != strlen(name)) {
			LOG("write failed (name)");
			errno = EINVAL;
			return -1;
		}
	} else {
		TRACE("Checking magic (cli_magic)");

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

	if (read_sync(csock, &s, sizeof(s)) != sizeof(s)) {
		LOG("read failed");
		errno = EINVAL;
		return -1;
	}
	*size = be64_to_cpu(s);
	*blocksize = 1024;
	TRACE("Size is %" PRIu64, *size);

	if (!name) {
		if (read_sync(csock, flags, sizeof(*flags)) != sizeof(*flags)) {
			LOG("read failed (flags)");
			errno = EINVAL;
			return -1;
		}
		*flags = be32_to_cpup(flags);
	} else {
		if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) {
			LOG("read failed (tmp)");
			errno = EINVAL;
			return -1;
		}
		*flags |= be32_to_cpu(tmp);
	}
	if (read_sync(csock, &buf, 124) != 124) {
		LOG("read failed (buf)");
		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 %zd block(s)", (size_t)(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 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)
{
    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
8167ee88	16	* along with this program; if not, see <http://www.gnu.org/licenses/>.
75818250	17	*/
7a5ca864 FB	18
	19	#include "nbd.h"
	20
	21	#include <errno.h>
	22	#include <string.h>
03ff3ca3	23	#ifndef _WIN32
7a5ca864	24	#include <sys/ioctl.h>
03ff3ca3	25	#endif
7e00eb9b AL	26	#ifdef __sun__
	27	#include <sys/ioccom.h>
	28	#endif
7a5ca864 FB	29	#include <ctype.h>
7a5ca864 FB	30	#include <inttypes.h>
75818250	31
03ff3ca3 AL	32	#include "qemu_socket.h"
	33
	34	//#define DEBUG_NBD
	35
	36	#ifdef DEBUG_NBD
75818250	37	#define TRACE(msg, ...) do { \
03ff3ca3	38	LOG(msg, ## __VA_ARGS__); \
75818250	39	} while(0)
03ff3ca3 AL	40	#else
	41	#define TRACE(msg, ...) \
	42	do { } while (0)
	43	#endif
7a5ca864 FB	44
	45	#define LOG(msg, ...) do { \
	46	fprintf(stderr, "%s:%s():L%d: " msg "\n", \
	47	__FILE__, __FUNCTION__, __LINE__, ## __VA_ARGS__); \
	48	} while(0)
	49
7a5ca864 FB	50	/* This is all part of the "official" NBD API */
	51
	52	#define NBD_REQUEST_MAGIC 0x25609513
	53	#define NBD_REPLY_MAGIC 0x67446698
	54
	55	#define NBD_SET_SOCK _IO(0xab, 0)
	56	#define NBD_SET_BLKSIZE _IO(0xab, 1)
	57	#define NBD_SET_SIZE _IO(0xab, 2)
	58	#define NBD_DO_IT _IO(0xab, 3)
	59	#define NBD_CLEAR_SOCK _IO(0xab, 4)
	60	#define NBD_CLEAR_QUE _IO(0xab, 5)
	61	#define NBD_PRINT_DEBUG _IO(0xab, 6)
	62	#define NBD_SET_SIZE_BLOCKS _IO(0xab, 7)
	63	#define NBD_DISCONNECT _IO(0xab, 8)
	64
1d45f8b5 LV	65	#define NBD_OPT_EXPORT_NAME (1 << 0)
1d45f8b5 LV	66
7a5ca864 FB	67	/* That's all folks */
7a5ca864 FB	68
75818250 TS	69	#define read_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, true)
75818250 TS	70	#define write_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, false)
7a5ca864	71
75818250	72	size_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read)
7a5ca864 FB	73	{
	74	size_t offset = 0;
	75
	76	while (offset < size) {
	77	ssize_t len;
	78
	79	if (do_read) {
03ff3ca3	80	len = recv(fd, buffer + offset, size - offset, 0);
7a5ca864	81	} else {
03ff3ca3	82	len = send(fd, buffer + offset, size - offset, 0);
7a5ca864 FB	83	}
7a5ca864 FB	84
03ff3ca3 AL	85	if (len == -1)
	86	errno = socket_error();
	87
7a5ca864	88	/* recoverable error */
75818250	89	if (len == -1 && (errno == EAGAIN \|\| errno == EINTR)) {
7a5ca864 FB	90	continue;
	91	}
	92
	93	/* eof */
	94	if (len == 0) {
	95	break;
	96	}
	97
	98	/* unrecoverable error */
	99	if (len == -1) {
	100	return 0;
	101	}
	102
	103	offset += len;
	104	}
	105
	106	return offset;
	107	}
	108
75818250	109	int tcp_socket_outgoing(const char *address, uint16_t port)
7a5ca864 FB	110	{
	111	int s;
	112	struct in_addr in;
	113	struct sockaddr_in addr;
7a5ca864 FB	114
	115	s = socket(PF_INET, SOCK_STREAM, 0);
	116	if (s == -1) {
	117	return -1;
	118	}
	119
	120	if (inet_aton(address, &in) == 0) {
	121	struct hostent *ent;
	122
	123	ent = gethostbyname(address);
	124	if (ent == NULL) {
	125	goto error;
	126	}
	127
	128	memcpy(&in, ent->h_addr, sizeof(in));
	129	}
	130
	131	addr.sin_family = AF_INET;
	132	addr.sin_port = htons(port);
	133	memcpy(&addr.sin_addr.s_addr, &in, sizeof(in));
	134
	135	if (connect(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
	136	goto error;
	137	}
	138
	139	return s;
	140	error:
03ff3ca3	141	closesocket(s);
7a5ca864 FB	142	return -1;
	143	}
	144
	145	int tcp_socket_incoming(const char *address, uint16_t port)
	146	{
	147	int s;
	148	struct in_addr in;
	149	struct sockaddr_in addr;
7a5ca864 FB	150	int opt;
	151
	152	s = socket(PF_INET, SOCK_STREAM, 0);
	153	if (s == -1) {
	154	return -1;
	155	}
	156
	157	if (inet_aton(address, &in) == 0) {
	158	struct hostent *ent;
	159
	160	ent = gethostbyname(address);
	161	if (ent == NULL) {
	162	goto error;
	163	}
	164
	165	memcpy(&in, ent->h_addr, sizeof(in));
	166	}
	167
	168	addr.sin_family = AF_INET;
	169	addr.sin_port = htons(port);
	170	memcpy(&addr.sin_addr.s_addr, &in, sizeof(in));
	171
	172	opt = 1;
0a656f5f	173	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
0a656f5f	174	(const void *) &opt, sizeof(opt)) == -1) {
7a5ca864 FB	175	goto error;
	176	}
	177
	178	if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
	179	goto error;
	180	}
	181
	182	if (listen(s, 128) == -1) {
	183	goto error;
	184	}
	185
	186	return s;
	187	error:
03ff3ca3	188	closesocket(s);
7a5ca864 FB	189	return -1;
	190	}
	191
03ff3ca3	192	#ifndef _WIN32
cd831bd7 TS	193	int unix_socket_incoming(const char *path)
	194	{
	195	int s;
	196	struct sockaddr_un addr;
cd831bd7 TS	197
	198	s = socket(PF_UNIX, SOCK_STREAM, 0);
	199	if (s == -1) {
	200	return -1;
	201	}
	202
	203	memset(&addr, 0, sizeof(addr));
	204	addr.sun_family = AF_UNIX;
	205	pstrcpy(addr.sun_path, sizeof(addr.sun_path), path);
	206
	207	if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
	208	goto error;
	209	}
	210
	211	if (listen(s, 128) == -1) {
	212	goto error;
	213	}
	214
	215	return s;
	216	error:
03ff3ca3	217	closesocket(s);
cd831bd7 TS	218	return -1;
	219	}
	220
	221	int unix_socket_outgoing(const char *path)
	222	{
	223	int s;
	224	struct sockaddr_un addr;
cd831bd7 TS	225
	226	s = socket(PF_UNIX, SOCK_STREAM, 0);
	227	if (s == -1) {
	228	return -1;
	229	}
	230
	231	memset(&addr, 0, sizeof(addr));
	232	addr.sun_family = AF_UNIX;
	233	pstrcpy(addr.sun_path, sizeof(addr.sun_path), path);
	234
	235	if (connect(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
	236	goto error;
	237	}
	238
	239	return s;
	240	error:
03ff3ca3 AL	241	closesocket(s);
	242	return -1;
	243	}
	244	#else
	245	int unix_socket_incoming(const char *path)
	246	{
	247	errno = ENOTSUP;
cd831bd7 TS	248	return -1;
	249	}
	250
03ff3ca3 AL	251	int unix_socket_outgoing(const char *path)
	252	{
	253	errno = ENOTSUP;
	254	return -1;
	255	}
	256	#endif
	257
cd831bd7	258
7a5ca864 FB	259	/* Basic flow
	260
	261	Server Client
	262
	263	Negotiate
	264	Request
	265	Response
	266	Request
	267	Response
	268	...
	269	...
	270	Request (type == 2)
	271	*/
	272
27982661	273	int nbd_negotiate(int csock, off_t size)
7a5ca864 FB	274	{
	275	char buf[8 + 8 + 8 + 128];
	276
	277	/* Negotiate
	278	[ 0 .. 7] passwd ("NBDMAGIC")
	279	[ 8 .. 15] magic (0x00420281861253)
	280	[16 .. 23] size
	281	[24 .. 151] reserved (0)
	282	*/
	283
	284	TRACE("Beginning negotiation.");
	285	memcpy(buf, "NBDMAGIC", 8);
	286	cpu_to_be64w((uint64_t*)(buf + 8), 0x00420281861253LL);
	287	cpu_to_be64w((uint64_t*)(buf + 16), size);
	288	memset(buf + 24, 0, 128);
	289
	290	if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
	291	LOG("write failed");
	292	errno = EINVAL;
	293	return -1;
	294	}
	295
	296	TRACE("Negotation succeeded.");
	297
	298	return 0;
	299	}
	300
1d45f8b5 LV	301	int nbd_receive_negotiate(int csock, const char name, uint32_t flags,
1d45f8b5 LV	302	off_t size, size_t blocksize)
7a5ca864	303	{
1d45f8b5 LV	304	char buf[256];
	305	uint64_t magic, s;
	306	uint16_t tmp;
7a5ca864 FB	307
	308	TRACE("Receiving negotation.");
	309
1d45f8b5	310	if (read_sync(csock, buf, 8) != 8) {
7a5ca864 FB	311	LOG("read failed");
	312	errno = EINVAL;
	313	return -1;
	314	}
	315
1d45f8b5 LV	316	buf[8] = '\0';
	317	if (strlen(buf) == 0) {
	318	LOG("server connection closed");
	319	errno = EINVAL;
	320	return -1;
	321	}
7a5ca864 FB	322
7a5ca864 FB	323	TRACE("Magic is %c%c%c%c%c%c%c%c",
47398b9c BS	324	qemu_isprint(buf[0]) ? buf[0] : '.',
	325	qemu_isprint(buf[1]) ? buf[1] : '.',
	326	qemu_isprint(buf[2]) ? buf[2] : '.',
	327	qemu_isprint(buf[3]) ? buf[3] : '.',
	328	qemu_isprint(buf[4]) ? buf[4] : '.',
	329	qemu_isprint(buf[5]) ? buf[5] : '.',
	330	qemu_isprint(buf[6]) ? buf[6] : '.',
	331	qemu_isprint(buf[7]) ? buf[7] : '.');
7a5ca864 FB	332
	333	if (memcmp(buf, "NBDMAGIC", 8) != 0) {
	334	LOG("Invalid magic received");
	335	errno = EINVAL;
	336	return -1;
	337	}
	338
1d45f8b5 LV	339	if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) {
	340	LOG("read failed");
	341	errno = EINVAL;
	342	return -1;
	343	}
	344	magic = be64_to_cpu(magic);
	345	TRACE("Magic is 0x%" PRIx64, magic);
	346
	347	if (name) {
	348	uint32_t reserved = 0;
	349	uint32_t opt;
	350	uint32_t namesize;
	351
	352	TRACE("Checking magic (opts_magic)");
	353	if (magic != 0x49484156454F5054LL) {
	354	LOG("Bad magic received");
	355	errno = EINVAL;
	356	return -1;
	357	}
	358	if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) {
	359	LOG("flags read failed");
	360	errno = EINVAL;
	361	return -1;
	362	}
	363	*flags = be16_to_cpu(tmp) << 16;
	364	/* reserved for future use */
	365	if (write_sync(csock, &reserved, sizeof(reserved)) !=
	366	sizeof(reserved)) {
	367	LOG("write failed (reserved)");
	368	errno = EINVAL;
	369	return -1;
	370	}
	371	/* write the export name */
	372	magic = cpu_to_be64(magic);
	373	if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) {
	374	LOG("write failed (magic)");
	375	errno = EINVAL;
	376	return -1;
	377	}
	378	opt = cpu_to_be32(NBD_OPT_EXPORT_NAME);
	379	if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) {
	380	LOG("write failed (opt)");
	381	errno = EINVAL;
	382	return -1;
	383	}
	384	namesize = cpu_to_be32(strlen(name));
	385	if (write_sync(csock, &namesize, sizeof(namesize)) !=
	386	sizeof(namesize)) {
	387	LOG("write failed (namesize)");
	388	errno = EINVAL;
	389	return -1;
	390	}
	391	if (write_sync(csock, (char*)name, strlen(name)) != strlen(name)) {
	392	LOG("write failed (name)");
	393	errno = EINVAL;
	394	return -1;
	395	}
	396	} else {
	397	TRACE("Checking magic (cli_magic)");
	398
	399	if (magic != 0x00420281861253LL) {
	400	LOG("Bad magic received");
	401	errno = EINVAL;
	402	return -1;
403	}
404	}
7a5ca864	405
1d45f8b5 LV	406	if (read_sync(csock, &s, sizeof(s)) != sizeof(s)) {
	407	LOG("read failed");
	408	errno = EINVAL;
	409	return -1;
	410	}
	411	*size = be64_to_cpu(s);
	412	*blocksize = 1024;
	413	TRACE("Size is %" PRIu64, *size);
	414
	415	if (!name) {
	416	if (read_sync(csock, flags, sizeof(flags)) != sizeof(flags)) {
	417	LOG("read failed (flags)");
	418	errno = EINVAL;
	419	return -1;
	420	}
	421	*flags = be32_to_cpup(flags);
	422	} else {
	423	if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) {
	424	LOG("read failed (tmp)");
	425	errno = EINVAL;
	426	return -1;
	427	}
	428	*flags \|= be32_to_cpu(tmp);
	429	}
	430	if (read_sync(csock, &buf, 124) != 124) {
	431	LOG("read failed (buf)");
7a5ca864 FB	432	errno = EINVAL;
	433	return -1;
	434	}
cd831bd7 TS	435	return 0;
cd831bd7 TS	436	}
7a5ca864	437
03ff3ca3	438	#ifndef _WIN32
cd831bd7 TS	439	int nbd_init(int fd, int csock, off_t size, size_t blocksize)
cd831bd7 TS	440	{
7a5ca864 FB	441	TRACE("Setting block size to %lu", (unsigned long)blocksize);
	442
	443	if (ioctl(fd, NBD_SET_BLKSIZE, blocksize) == -1) {
	444	int serrno = errno;
	445	LOG("Failed setting NBD block size");
	446	errno = serrno;
	447	return -1;
	448	}
	449
0bfcd599	450	TRACE("Setting size to %zd block(s)", (size_t)(size / blocksize));
7a5ca864 FB	451
	452	if (ioctl(fd, NBD_SET_SIZE_BLOCKS, size / blocksize) == -1) {
	453	int serrno = errno;
	454	LOG("Failed setting size (in blocks)");
	455	errno = serrno;
	456	return -1;
	457	}
	458
	459	TRACE("Clearing NBD socket");
	460
	461	if (ioctl(fd, NBD_CLEAR_SOCK) == -1) {
	462	int serrno = errno;
	463	LOG("Failed clearing NBD socket");
	464	errno = serrno;
	465	return -1;
	466	}
	467
	468	TRACE("Setting NBD socket");
	469
	470	if (ioctl(fd, NBD_SET_SOCK, csock) == -1) {
	471	int serrno = errno;
	472	LOG("Failed to set NBD socket");
	473	errno = serrno;
	474	return -1;
	475	}
	476
	477	TRACE("Negotiation ended");
	478
	479	return 0;
	480	}
	481
	482	int nbd_disconnect(int fd)
	483	{
	484	ioctl(fd, NBD_CLEAR_QUE);
	485	ioctl(fd, NBD_DISCONNECT);
	486	ioctl(fd, NBD_CLEAR_SOCK);
	487	return 0;
	488	}
	489
0a4eb864	490	int nbd_client(int fd)
7a5ca864 FB	491	{
	492	int ret;
	493	int serrno;
	494
	495	TRACE("Doing NBD loop");
	496
	497	ret = ioctl(fd, NBD_DO_IT);
	498	serrno = errno;
	499
	500	TRACE("NBD loop returned %d: %s", ret, strerror(serrno));
	501
	502	TRACE("Clearing NBD queue");
	503	ioctl(fd, NBD_CLEAR_QUE);
	504
	505	TRACE("Clearing NBD socket");
	506	ioctl(fd, NBD_CLEAR_SOCK);
	507
	508	errno = serrno;
	509	return ret;
	510	}
03ff3ca3 AL	511	#else
	512	int nbd_init(int fd, int csock, off_t size, size_t blocksize)
	513	{
	514	errno = ENOTSUP;
	515	return -1;
	516	}
	517
	518	int nbd_disconnect(int fd)
	519	{
	520	errno = ENOTSUP;
	521	return -1;
	522	}
	523
0a4eb864	524	int nbd_client(int fd)
03ff3ca3 AL	525	{
	526	errno = ENOTSUP;
	527	return -1;
	528	}
	529	#endif
7a5ca864	530
75818250	531	int nbd_send_request(int csock, struct nbd_request *request)
7a5ca864	532	{
7a5ca864	533	uint8_t buf[4 + 4 + 8 + 8 + 4];
7a5ca864	534
75818250 TS	535	cpu_to_be32w((uint32_t*)buf, NBD_REQUEST_MAGIC);
	536	cpu_to_be32w((uint32_t*)(buf + 4), request->type);
	537	cpu_to_be64w((uint64_t*)(buf + 8), request->handle);
	538	cpu_to_be64w((uint64_t*)(buf + 16), request->from);
	539	cpu_to_be32w((uint32_t*)(buf + 24), request->len);
	540
	541	TRACE("Sending request to client");
	542
	543	if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
	544	LOG("writing to socket failed");
	545	errno = EINVAL;
	546	return -1;
	547	}
	548	return 0;
	549	}
	550
	551
	552	static int nbd_receive_request(int csock, struct nbd_request *request)
	553	{
	554	uint8_t buf[4 + 4 + 8 + 8 + 4];
	555	uint32_t magic;
7a5ca864 FB	556
	557	if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
	558	LOG("read failed");
	559	errno = EINVAL;
	560	return -1;
	561	}
	562
	563	/* Request
75818250 TS	564	[ 0 .. 3] magic (NBD_REQUEST_MAGIC)
	565	[ 4 .. 7] type (0 == READ, 1 == WRITE)
	566	[ 8 .. 15] handle
	567	[16 .. 23] from
	568	[24 .. 27] len
7a5ca864 FB	569	*/
	570
	571	magic = be32_to_cpup((uint32_t*)buf);
75818250 TS	572	request->type = be32_to_cpup((uint32_t*)(buf + 4));
	573	request->handle = be64_to_cpup((uint64_t*)(buf + 8));
	574	request->from = be64_to_cpup((uint64_t*)(buf + 16));
	575	request->len = be32_to_cpup((uint32_t*)(buf + 24));
7a5ca864 FB	576
	577	TRACE("Got request: "
	578	"{ magic = 0x%x, .type = %d, from = %" PRIu64" , len = %u }",
75818250	579	magic, request->type, request->from, request->len);
7a5ca864 FB	580
	581	if (magic != NBD_REQUEST_MAGIC) {
	582	LOG("invalid magic (got 0x%x)", magic);
	583	errno = EINVAL;
	584	return -1;
	585	}
d94888e3	586	return 0;
75818250 TS	587	}
	588
	589	int nbd_receive_reply(int csock, struct nbd_reply *reply)
	590	{
	591	uint8_t buf[4 + 4 + 8];
	592	uint32_t magic;
	593
	594	memset(buf, 0xAA, sizeof(buf));
	595
	596	if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
	597	LOG("read failed");
	598	errno = EINVAL;
	599	return -1;
	600	}
	601
	602	/* Reply
	603	[ 0 .. 3] magic (NBD_REPLY_MAGIC)
	604	[ 4 .. 7] error (0 == no error)
	605	[ 7 .. 15] handle
	606	*/
	607
	608	magic = be32_to_cpup((uint32_t*)buf);
	609	reply->error = be32_to_cpup((uint32_t*)(buf + 4));
	610	reply->handle = be64_to_cpup((uint64_t*)(buf + 8));
	611
	612	TRACE("Got reply: "
	613	"{ magic = 0x%x, .error = %d, handle = %" PRIu64" }",
	614	magic, reply->error, reply->handle);
	615
	616	if (magic != NBD_REPLY_MAGIC) {
	617	LOG("invalid magic (got 0x%x)", magic);
	618	errno = EINVAL;
	619	return -1;
	620	}
	621	return 0;
	622	}
	623
	624	static int nbd_send_reply(int csock, struct nbd_reply *reply)
	625	{
	626	uint8_t buf[4 + 4 + 8];
	627
	628	/* Reply
	629	[ 0 .. 3] magic (NBD_REPLY_MAGIC)
	630	[ 4 .. 7] error (0 == no error)
	631	[ 7 .. 15] handle
	632	*/
	633	cpu_to_be32w((uint32_t*)buf, NBD_REPLY_MAGIC);
	634	cpu_to_be32w((uint32_t*)(buf + 4), reply->error);
	635	cpu_to_be64w((uint64_t*)(buf + 8), reply->handle);
	636
	637	TRACE("Sending response to client");
	638
	639	if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
	640	LOG("writing to socket failed");
	641	errno = EINVAL;
	642	return -1;
	643	}
	644	return 0;
	645	}
7a5ca864	646
75818250 TS	647	int nbd_trip(BlockDriverState *bs, int csock, off_t size, uint64_t dev_offset,
	648	off_t offset, bool readonly, uint8_t data, int data_size)
	649	{
	650	struct nbd_request request;
	651	struct nbd_reply reply;
	652
	653	TRACE("Reading request.");
	654
	655	if (nbd_receive_request(csock, &request) == -1)
	656	return -1;
	657
	658	if (request.len > data_size) {
2f726488	659	LOG("len (%u) is larger than max len (%u)",
75818250	660	request.len, data_size);
7a5ca864 FB	661	errno = EINVAL;
	662	return -1;
	663	}
	664
75818250	665	if ((request.from + request.len) < request.from) {
7a5ca864 FB	666	LOG("integer overflow detected! "
	667	"you're probably being attacked");
	668	errno = EINVAL;
	669	return -1;
	670	}
	671
75818250	672	if ((request.from + request.len) > size) {
7a5ca864 FB	673	LOG("From: %" PRIu64 ", Len: %u, Size: %" PRIu64
7a5ca864 FB	674	", Offset: %" PRIu64 "\n",
b9e82a59	675	request.from, request.len, (uint64_t)size, dev_offset);
7a5ca864 FB	676	LOG("requested operation past EOF--bad client?");
	677	errno = EINVAL;
	678	return -1;
	679	}
	680
7a5ca864 FB	681	TRACE("Decoding type");
7a5ca864 FB	682
75818250 TS	683	reply.handle = request.handle;
	684	reply.error = 0;
	685
	686	switch (request.type) {
	687	case NBD_CMD_READ:
7a5ca864 FB	688	TRACE("Request type is READ");
7a5ca864 FB	689
75818250 TS	690	if (bdrv_read(bs, (request.from + dev_offset) / 512, data,
75818250 TS	691	request.len / 512) == -1) {
7a5ca864 FB	692	LOG("reading from file failed");
	693	errno = EINVAL;
	694	return -1;
	695	}
75818250	696	*offset += request.len;
7a5ca864	697
75818250	698	TRACE("Read %u byte(s)", request.len);
7a5ca864	699
75818250	700	if (nbd_send_reply(csock, &reply) == -1)
7a5ca864	701	return -1;
7a5ca864 FB	702
	703	TRACE("Sending data to client");
	704
75818250	705	if (write_sync(csock, data, request.len) != request.len) {
7a5ca864 FB	706	LOG("writing to socket failed");
	707	errno = EINVAL;
	708	return -1;
	709	}
	710	break;
75818250	711	case NBD_CMD_WRITE:
7a5ca864 FB	712	TRACE("Request type is WRITE");
7a5ca864 FB	713
75818250	714	TRACE("Reading %u byte(s)", request.len);
7a5ca864	715
75818250	716	if (read_sync(csock, data, request.len) != request.len) {
7a5ca864 FB	717	LOG("reading from socket failed");
	718	errno = EINVAL;
	719	return -1;
	720	}
	721
	722	if (readonly) {
	723	TRACE("Server is read-only, return error");
75818250	724	reply.error = 1;
7a5ca864 FB	725	} else {
	726	TRACE("Writing to device");
	727
75818250 TS	728	if (bdrv_write(bs, (request.from + dev_offset) / 512,
75818250 TS	729	data, request.len / 512) == -1) {
7a5ca864 FB	730	LOG("writing to file failed");
	731	errno = EINVAL;
	732	return -1;
	733	}
	734
75818250	735	*offset += request.len;
7a5ca864 FB	736	}
7a5ca864 FB	737
75818250	738	if (nbd_send_reply(csock, &reply) == -1)
7a5ca864	739	return -1;
7a5ca864	740	break;
75818250	741	case NBD_CMD_DISC:
7a5ca864 FB	742	TRACE("Request type is DISCONNECT");
	743	errno = 0;
	744	return 1;
	745	default:
75818250	746	LOG("invalid request type (%u) received", request.type);
7a5ca864 FB	747	errno = EINVAL;
	748	return -1;
	749	}
	750
	751	TRACE("Request/Reply complete");
	752
	753	return 0;
	754	}