[qemu.git] / nbd.c

/*
 *  Copyright (C) 2005  Anthony Liguori <anthony@codemonkey.ws>
 *
 *  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
#if defined(__sun__) || defined(__HAIKU__)
#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_REPLY_SIZE		(4 + 4 + 8)
#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[NBD_REPLY_SIZE];
	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 + NBD_REPLY_SIZE > data_size) {
		LOG("len (%u) is larger than max len (%u)",
		    request.len + NBD_REPLY_SIZE, 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 + NBD_REPLY_SIZE,
			      request.len / 512) == -1) {
			LOG("reading from file failed");
			errno = EINVAL;
			return -1;
		}
		*offset += request.len;

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

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

		cpu_to_be32w((uint32_t*)data, NBD_REPLY_MAGIC);
		cpu_to_be32w((uint32_t*)(data + 4), reply.error);
		cpu_to_be64w((uint64_t*)(data + 8), reply.handle);

		TRACE("Sending data to client");

		if (write_sync(csock, data,
			       request.len + NBD_REPLY_SIZE) !=
			       request.len + NBD_REPLY_SIZE) {
			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 <anthony@codemonkey.ws>
	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
5dc2eec9	26	#if defined(__sun__) \|\| defined(__HAIKU__)
7e00eb9b AL	27	#include <sys/ioccom.h>
7e00eb9b AL	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 */
7a5ca864 FB	51
5fe16888	52	#define NBD_REPLY_SIZE (4 + 4 + 8)
7a5ca864 FB	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
1d45f8b5 LV	66	#define NBD_OPT_EXPORT_NAME (1 << 0)
1d45f8b5 LV	67
7a5ca864 FB	68	/* That's all folks */
7a5ca864 FB	69
75818250 TS	70	#define read_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, true)
75818250 TS	71	#define write_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, false)
7a5ca864	72
75818250	73	size_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read)
7a5ca864 FB	74	{
	75	size_t offset = 0;
	76
	77	while (offset < size) {
	78	ssize_t len;
	79
	80	if (do_read) {
03ff3ca3	81	len = recv(fd, buffer + offset, size - offset, 0);
7a5ca864	82	} else {
03ff3ca3	83	len = send(fd, buffer + offset, size - offset, 0);
7a5ca864 FB	84	}
7a5ca864 FB	85
03ff3ca3 AL	86	if (len == -1)
	87	errno = socket_error();
	88
7a5ca864	89	/* recoverable error */
75818250	90	if (len == -1 && (errno == EAGAIN \|\| errno == EINTR)) {
7a5ca864 FB	91	continue;
	92	}
	93
	94	/* eof */
	95	if (len == 0) {
	96	break;
	97	}
	98
	99	/* unrecoverable error */
	100	if (len == -1) {
	101	return 0;
	102	}
	103
	104	offset += len;
	105	}
	106
	107	return offset;
	108	}
	109
75818250	110	int tcp_socket_outgoing(const char *address, uint16_t port)
7a5ca864 FB	111	{
	112	int s;
	113	struct in_addr in;
	114	struct sockaddr_in addr;
7a5ca864 FB	115
	116	s = socket(PF_INET, SOCK_STREAM, 0);
	117	if (s == -1) {
	118	return -1;
	119	}
	120
	121	if (inet_aton(address, &in) == 0) {
	122	struct hostent *ent;
	123
	124	ent = gethostbyname(address);
	125	if (ent == NULL) {
	126	goto error;
	127	}
	128
	129	memcpy(&in, ent->h_addr, sizeof(in));
	130	}
	131
	132	addr.sin_family = AF_INET;
	133	addr.sin_port = htons(port);
	134	memcpy(&addr.sin_addr.s_addr, &in, sizeof(in));
	135
	136	if (connect(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
	137	goto error;
	138	}
	139
	140	return s;
	141	error:
03ff3ca3	142	closesocket(s);
7a5ca864 FB	143	return -1;
	144	}
	145
	146	int tcp_socket_incoming(const char *address, uint16_t port)
	147	{
	148	int s;
	149	struct in_addr in;
	150	struct sockaddr_in addr;
7a5ca864 FB	151	int opt;
	152
	153	s = socket(PF_INET, SOCK_STREAM, 0);
	154	if (s == -1) {
	155	return -1;
	156	}
	157
	158	if (inet_aton(address, &in) == 0) {
	159	struct hostent *ent;
	160
	161	ent = gethostbyname(address);
	162	if (ent == NULL) {
	163	goto error;
	164	}
	165
	166	memcpy(&in, ent->h_addr, sizeof(in));
	167	}
	168
	169	addr.sin_family = AF_INET;
	170	addr.sin_port = htons(port);
	171	memcpy(&addr.sin_addr.s_addr, &in, sizeof(in));
	172
	173	opt = 1;
0a656f5f	174	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
0a656f5f	175	(const void *) &opt, sizeof(opt)) == -1) {
7a5ca864 FB	176	goto error;
	177	}
	178
	179	if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
	180	goto error;
	181	}
	182
	183	if (listen(s, 128) == -1) {
	184	goto error;
	185	}
	186
	187	return s;
	188	error:
03ff3ca3	189	closesocket(s);
7a5ca864 FB	190	return -1;
	191	}
	192
03ff3ca3	193	#ifndef _WIN32
cd831bd7 TS	194	int unix_socket_incoming(const char *path)
	195	{
	196	int s;
	197	struct sockaddr_un addr;
cd831bd7 TS	198
	199	s = socket(PF_UNIX, SOCK_STREAM, 0);
	200	if (s == -1) {
	201	return -1;
	202	}
	203
	204	memset(&addr, 0, sizeof(addr));
	205	addr.sun_family = AF_UNIX;
	206	pstrcpy(addr.sun_path, sizeof(addr.sun_path), path);
	207
	208	if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
	209	goto error;
	210	}
	211
	212	if (listen(s, 128) == -1) {
	213	goto error;
	214	}
	215
	216	return s;
	217	error:
03ff3ca3	218	closesocket(s);
cd831bd7 TS	219	return -1;
	220	}
	221
	222	int unix_socket_outgoing(const char *path)
	223	{
	224	int s;
	225	struct sockaddr_un addr;
cd831bd7 TS	226
	227	s = socket(PF_UNIX, SOCK_STREAM, 0);
	228	if (s == -1) {
	229	return -1;
	230	}
	231
	232	memset(&addr, 0, sizeof(addr));
	233	addr.sun_family = AF_UNIX;
	234	pstrcpy(addr.sun_path, sizeof(addr.sun_path), path);
	235
	236	if (connect(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
	237	goto error;
	238	}
	239
	240	return s;
	241	error:
03ff3ca3 AL	242	closesocket(s);
	243	return -1;
	244	}
	245	#else
	246	int unix_socket_incoming(const char *path)
	247	{
	248	errno = ENOTSUP;
cd831bd7 TS	249	return -1;
	250	}
	251
03ff3ca3 AL	252	int unix_socket_outgoing(const char *path)
	253	{
	254	errno = ENOTSUP;
	255	return -1;
	256	}
	257	#endif
	258
cd831bd7	259
7a5ca864 FB	260	/* Basic flow
	261
	262	Server Client
	263
	264	Negotiate
	265	Request
	266	Response
	267	Request
	268	Response
	269	...
	270	...
	271	Request (type == 2)
	272	*/
	273
27982661	274	int nbd_negotiate(int csock, off_t size)
7a5ca864 FB	275	{
	276	char buf[8 + 8 + 8 + 128];
	277
	278	/* Negotiate
	279	[ 0 .. 7] passwd ("NBDMAGIC")
	280	[ 8 .. 15] magic (0x00420281861253)
	281	[16 .. 23] size
	282	[24 .. 151] reserved (0)
	283	*/
	284
	285	TRACE("Beginning negotiation.");
	286	memcpy(buf, "NBDMAGIC", 8);
	287	cpu_to_be64w((uint64_t*)(buf + 8), 0x00420281861253LL);
	288	cpu_to_be64w((uint64_t*)(buf + 16), size);
	289	memset(buf + 24, 0, 128);
	290
	291	if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
	292	LOG("write failed");
	293	errno = EINVAL;
	294	return -1;
	295	}
	296
	297	TRACE("Negotation succeeded.");
	298
	299	return 0;
	300	}
	301
1d45f8b5 LV	302	int nbd_receive_negotiate(int csock, const char name, uint32_t flags,
1d45f8b5 LV	303	off_t size, size_t blocksize)
7a5ca864	304	{
1d45f8b5 LV	305	char buf[256];
	306	uint64_t magic, s;
	307	uint16_t tmp;
7a5ca864 FB	308
	309	TRACE("Receiving negotation.");
	310
1d45f8b5	311	if (read_sync(csock, buf, 8) != 8) {
7a5ca864 FB	312	LOG("read failed");
	313	errno = EINVAL;
	314	return -1;
	315	}
	316
1d45f8b5 LV	317	buf[8] = '\0';
	318	if (strlen(buf) == 0) {
	319	LOG("server connection closed");
	320	errno = EINVAL;
	321	return -1;
	322	}
7a5ca864 FB	323
7a5ca864 FB	324	TRACE("Magic is %c%c%c%c%c%c%c%c",
47398b9c BS	325	qemu_isprint(buf[0]) ? buf[0] : '.',
	326	qemu_isprint(buf[1]) ? buf[1] : '.',
	327	qemu_isprint(buf[2]) ? buf[2] : '.',
	328	qemu_isprint(buf[3]) ? buf[3] : '.',
	329	qemu_isprint(buf[4]) ? buf[4] : '.',
	330	qemu_isprint(buf[5]) ? buf[5] : '.',
	331	qemu_isprint(buf[6]) ? buf[6] : '.',
	332	qemu_isprint(buf[7]) ? buf[7] : '.');
7a5ca864 FB	333
	334	if (memcmp(buf, "NBDMAGIC", 8) != 0) {
	335	LOG("Invalid magic received");
	336	errno = EINVAL;
	337	return -1;
	338	}
	339
1d45f8b5 LV	340	if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) {
	341	LOG("read failed");
	342	errno = EINVAL;
	343	return -1;
	344	}
	345	magic = be64_to_cpu(magic);
	346	TRACE("Magic is 0x%" PRIx64, magic);
	347
	348	if (name) {
	349	uint32_t reserved = 0;
	350	uint32_t opt;
	351	uint32_t namesize;
	352
	353	TRACE("Checking magic (opts_magic)");
	354	if (magic != 0x49484156454F5054LL) {
	355	LOG("Bad magic received");
	356	errno = EINVAL;
	357	return -1;
	358	}
	359	if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) {
	360	LOG("flags read failed");
	361	errno = EINVAL;
	362	return -1;
	363	}
	364	*flags = be16_to_cpu(tmp) << 16;
	365	/* reserved for future use */
	366	if (write_sync(csock, &reserved, sizeof(reserved)) !=
	367	sizeof(reserved)) {
	368	LOG("write failed (reserved)");
	369	errno = EINVAL;
	370	return -1;
	371	}
	372	/* write the export name */
	373	magic = cpu_to_be64(magic);
	374	if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) {
	375	LOG("write failed (magic)");
	376	errno = EINVAL;
	377	return -1;
	378	}
	379	opt = cpu_to_be32(NBD_OPT_EXPORT_NAME);
	380	if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) {
	381	LOG("write failed (opt)");
	382	errno = EINVAL;
	383	return -1;
	384	}
	385	namesize = cpu_to_be32(strlen(name));
	386	if (write_sync(csock, &namesize, sizeof(namesize)) !=
	387	sizeof(namesize)) {
	388	LOG("write failed (namesize)");
	389	errno = EINVAL;
	390	return -1;
	391	}
	392	if (write_sync(csock, (char*)name, strlen(name)) != strlen(name)) {
	393	LOG("write failed (name)");
	394	errno = EINVAL;
	395	return -1;
	396	}
	397	} else {
	398	TRACE("Checking magic (cli_magic)");
	399
	400	if (magic != 0x00420281861253LL) {
	401	LOG("Bad magic received");
	402	errno = EINVAL;
	403	return -1;
404	}
405	}
7a5ca864	406
1d45f8b5 LV	407	if (read_sync(csock, &s, sizeof(s)) != sizeof(s)) {
	408	LOG("read failed");
	409	errno = EINVAL;
	410	return -1;
	411	}
	412	*size = be64_to_cpu(s);
	413	*blocksize = 1024;
	414	TRACE("Size is %" PRIu64, *size);
	415
	416	if (!name) {
	417	if (read_sync(csock, flags, sizeof(flags)) != sizeof(flags)) {
	418	LOG("read failed (flags)");
	419	errno = EINVAL;
	420	return -1;
	421	}
	422	*flags = be32_to_cpup(flags);
	423	} else {
	424	if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) {
	425	LOG("read failed (tmp)");
	426	errno = EINVAL;
	427	return -1;
	428	}
	429	*flags \|= be32_to_cpu(tmp);
	430	}
	431	if (read_sync(csock, &buf, 124) != 124) {
	432	LOG("read failed (buf)");
7a5ca864 FB	433	errno = EINVAL;
	434	return -1;
	435	}
cd831bd7 TS	436	return 0;
cd831bd7 TS	437	}
7a5ca864	438
03ff3ca3	439	#ifndef _WIN32
cd831bd7 TS	440	int nbd_init(int fd, int csock, off_t size, size_t blocksize)
cd831bd7 TS	441	{
7a5ca864 FB	442	TRACE("Setting block size to %lu", (unsigned long)blocksize);
	443
	444	if (ioctl(fd, NBD_SET_BLKSIZE, blocksize) == -1) {
	445	int serrno = errno;
	446	LOG("Failed setting NBD block size");
	447	errno = serrno;
	448	return -1;
	449	}
	450
0bfcd599	451	TRACE("Setting size to %zd block(s)", (size_t)(size / blocksize));
7a5ca864 FB	452
	453	if (ioctl(fd, NBD_SET_SIZE_BLOCKS, size / blocksize) == -1) {
	454	int serrno = errno;
	455	LOG("Failed setting size (in blocks)");
	456	errno = serrno;
	457	return -1;
	458	}
	459
	460	TRACE("Clearing NBD socket");
	461
	462	if (ioctl(fd, NBD_CLEAR_SOCK) == -1) {
	463	int serrno = errno;
	464	LOG("Failed clearing NBD socket");
	465	errno = serrno;
	466	return -1;
	467	}
	468
	469	TRACE("Setting NBD socket");
	470
	471	if (ioctl(fd, NBD_SET_SOCK, csock) == -1) {
	472	int serrno = errno;
	473	LOG("Failed to set NBD socket");
	474	errno = serrno;
	475	return -1;
	476	}
	477
	478	TRACE("Negotiation ended");
	479
	480	return 0;
	481	}
	482
	483	int nbd_disconnect(int fd)
	484	{
	485	ioctl(fd, NBD_CLEAR_QUE);
	486	ioctl(fd, NBD_DISCONNECT);
	487	ioctl(fd, NBD_CLEAR_SOCK);
	488	return 0;
	489	}
	490
0a4eb864	491	int nbd_client(int fd)
7a5ca864 FB	492	{
	493	int ret;
	494	int serrno;
	495
	496	TRACE("Doing NBD loop");
	497
	498	ret = ioctl(fd, NBD_DO_IT);
	499	serrno = errno;
	500
	501	TRACE("NBD loop returned %d: %s", ret, strerror(serrno));
	502
	503	TRACE("Clearing NBD queue");
	504	ioctl(fd, NBD_CLEAR_QUE);
	505
	506	TRACE("Clearing NBD socket");
	507	ioctl(fd, NBD_CLEAR_SOCK);
	508
	509	errno = serrno;
	510	return ret;
	511	}
03ff3ca3 AL	512	#else
	513	int nbd_init(int fd, int csock, off_t size, size_t blocksize)
	514	{
	515	errno = ENOTSUP;
	516	return -1;
	517	}
	518
	519	int nbd_disconnect(int fd)
	520	{
	521	errno = ENOTSUP;
	522	return -1;
	523	}
	524
0a4eb864	525	int nbd_client(int fd)
03ff3ca3 AL	526	{
	527	errno = ENOTSUP;
	528	return -1;
	529	}
	530	#endif
7a5ca864	531
75818250	532	int nbd_send_request(int csock, struct nbd_request *request)
7a5ca864	533	{
7a5ca864	534	uint8_t buf[4 + 4 + 8 + 8 + 4];
7a5ca864	535
75818250 TS	536	cpu_to_be32w((uint32_t*)buf, NBD_REQUEST_MAGIC);
	537	cpu_to_be32w((uint32_t*)(buf + 4), request->type);
	538	cpu_to_be64w((uint64_t*)(buf + 8), request->handle);
	539	cpu_to_be64w((uint64_t*)(buf + 16), request->from);
	540	cpu_to_be32w((uint32_t*)(buf + 24), request->len);
	541
	542	TRACE("Sending request to client");
	543
	544	if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
	545	LOG("writing to socket failed");
	546	errno = EINVAL;
	547	return -1;
	548	}
	549	return 0;
	550	}
	551
	552
	553	static int nbd_receive_request(int csock, struct nbd_request *request)
	554	{
	555	uint8_t buf[4 + 4 + 8 + 8 + 4];
	556	uint32_t magic;
7a5ca864 FB	557
	558	if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
	559	LOG("read failed");
	560	errno = EINVAL;
	561	return -1;
	562	}
	563
	564	/* Request
75818250 TS	565	[ 0 .. 3] magic (NBD_REQUEST_MAGIC)
	566	[ 4 .. 7] type (0 == READ, 1 == WRITE)
	567	[ 8 .. 15] handle
	568	[16 .. 23] from
	569	[24 .. 27] len
7a5ca864 FB	570	*/
	571
	572	magic = be32_to_cpup((uint32_t*)buf);
75818250 TS	573	request->type = be32_to_cpup((uint32_t*)(buf + 4));
	574	request->handle = be64_to_cpup((uint64_t*)(buf + 8));
	575	request->from = be64_to_cpup((uint64_t*)(buf + 16));
	576	request->len = be32_to_cpup((uint32_t*)(buf + 24));
7a5ca864 FB	577
	578	TRACE("Got request: "
	579	"{ magic = 0x%x, .type = %d, from = %" PRIu64" , len = %u }",
75818250	580	magic, request->type, request->from, request->len);
7a5ca864 FB	581
	582	if (magic != NBD_REQUEST_MAGIC) {
	583	LOG("invalid magic (got 0x%x)", magic);
	584	errno = EINVAL;
	585	return -1;
	586	}
d94888e3	587	return 0;
75818250 TS	588	}
	589
	590	int nbd_receive_reply(int csock, struct nbd_reply *reply)
	591	{
5fe16888	592	uint8_t buf[NBD_REPLY_SIZE];
75818250 TS	593	uint32_t magic;
	594
	595	memset(buf, 0xAA, sizeof(buf));
	596
	597	if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
	598	LOG("read failed");
	599	errno = EINVAL;
	600	return -1;
	601	}
	602
	603	/* Reply
	604	[ 0 .. 3] magic (NBD_REPLY_MAGIC)
	605	[ 4 .. 7] error (0 == no error)
	606	[ 7 .. 15] handle
	607	*/
	608
	609	magic = be32_to_cpup((uint32_t*)buf);
	610	reply->error = be32_to_cpup((uint32_t*)(buf + 4));
	611	reply->handle = be64_to_cpup((uint64_t*)(buf + 8));
	612
	613	TRACE("Got reply: "
	614	"{ magic = 0x%x, .error = %d, handle = %" PRIu64" }",
	615	magic, reply->error, reply->handle);
	616
	617	if (magic != NBD_REPLY_MAGIC) {
	618	LOG("invalid magic (got 0x%x)", magic);
	619	errno = EINVAL;
	620	return -1;
	621	}
	622	return 0;
	623	}
	624
	625	static int nbd_send_reply(int csock, struct nbd_reply *reply)
	626	{
	627	uint8_t buf[4 + 4 + 8];
	628
	629	/* Reply
	630	[ 0 .. 3] magic (NBD_REPLY_MAGIC)
	631	[ 4 .. 7] error (0 == no error)
	632	[ 7 .. 15] handle
	633	*/
	634	cpu_to_be32w((uint32_t*)buf, NBD_REPLY_MAGIC);
	635	cpu_to_be32w((uint32_t*)(buf + 4), reply->error);
	636	cpu_to_be64w((uint64_t*)(buf + 8), reply->handle);
	637
	638	TRACE("Sending response to client");
	639
	640	if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) {
	641	LOG("writing to socket failed");
	642	errno = EINVAL;
	643	return -1;
	644	}
	645	return 0;
	646	}
7a5ca864	647
75818250 TS	648	int nbd_trip(BlockDriverState *bs, int csock, off_t size, uint64_t dev_offset,
	649	off_t offset, bool readonly, uint8_t data, int data_size)
	650	{
	651	struct nbd_request request;
	652	struct nbd_reply reply;
	653
	654	TRACE("Reading request.");
	655
	656	if (nbd_receive_request(csock, &request) == -1)
	657	return -1;
	658
5fe16888	659	if (request.len + NBD_REPLY_SIZE > data_size) {
2f726488	660	LOG("len (%u) is larger than max len (%u)",
5fe16888	661	request.len + NBD_REPLY_SIZE, data_size);
7a5ca864 FB	662	errno = EINVAL;
	663	return -1;
	664	}
	665
75818250	666	if ((request.from + request.len) < request.from) {
7a5ca864 FB	667	LOG("integer overflow detected! "
	668	"you're probably being attacked");
	669	errno = EINVAL;
	670	return -1;
	671	}
	672
75818250	673	if ((request.from + request.len) > size) {
7a5ca864 FB	674	LOG("From: %" PRIu64 ", Len: %u, Size: %" PRIu64
7a5ca864 FB	675	", Offset: %" PRIu64 "\n",
b9e82a59	676	request.from, request.len, (uint64_t)size, dev_offset);
7a5ca864 FB	677	LOG("requested operation past EOF--bad client?");
	678	errno = EINVAL;
	679	return -1;
	680	}
	681
7a5ca864 FB	682	TRACE("Decoding type");
7a5ca864 FB	683
75818250 TS	684	reply.handle = request.handle;
	685	reply.error = 0;
	686
	687	switch (request.type) {
	688	case NBD_CMD_READ:
7a5ca864 FB	689	TRACE("Request type is READ");
7a5ca864 FB	690
5fe16888 LV	691	if (bdrv_read(bs, (request.from + dev_offset) / 512,
5fe16888 LV	692	data + NBD_REPLY_SIZE,
75818250	693	request.len / 512) == -1) {
7a5ca864 FB	694	LOG("reading from file failed");
	695	errno = EINVAL;
	696	return -1;
	697	}
75818250	698	*offset += request.len;
7a5ca864	699
75818250	700	TRACE("Read %u byte(s)", request.len);
7a5ca864	701
5fe16888 LV	702	/* Reply
	703	[ 0 .. 3] magic (NBD_REPLY_MAGIC)
	704	[ 4 .. 7] error (0 == no error)
	705	[ 7 .. 15] handle
	706	*/
	707
	708	cpu_to_be32w((uint32_t*)data, NBD_REPLY_MAGIC);
	709	cpu_to_be32w((uint32_t*)(data + 4), reply.error);
	710	cpu_to_be64w((uint64_t*)(data + 8), reply.handle);
7a5ca864 FB	711
	712	TRACE("Sending data to client");
	713
5fe16888 LV	714	if (write_sync(csock, data,
	715	request.len + NBD_REPLY_SIZE) !=
	716	request.len + NBD_REPLY_SIZE) {
7a5ca864 FB	717	LOG("writing to socket failed");
	718	errno = EINVAL;
	719	return -1;
	720	}
	721	break;
75818250	722	case NBD_CMD_WRITE:
7a5ca864 FB	723	TRACE("Request type is WRITE");
7a5ca864 FB	724
75818250	725	TRACE("Reading %u byte(s)", request.len);
7a5ca864	726
75818250	727	if (read_sync(csock, data, request.len) != request.len) {
7a5ca864 FB	728	LOG("reading from socket failed");
	729	errno = EINVAL;
	730	return -1;
	731	}
	732
	733	if (readonly) {
	734	TRACE("Server is read-only, return error");
75818250	735	reply.error = 1;
7a5ca864 FB	736	} else {
	737	TRACE("Writing to device");
	738
75818250 TS	739	if (bdrv_write(bs, (request.from + dev_offset) / 512,
75818250 TS	740	data, request.len / 512) == -1) {
7a5ca864 FB	741	LOG("writing to file failed");
	742	errno = EINVAL;
	743	return -1;
	744	}
	745
75818250	746	*offset += request.len;
7a5ca864 FB	747	}
7a5ca864 FB	748
75818250	749	if (nbd_send_reply(csock, &reply) == -1)
7a5ca864	750	return -1;
7a5ca864	751	break;
75818250	752	case NBD_CMD_DISC:
7a5ca864 FB	753	TRACE("Request type is DISCONNECT");
	754	errno = 0;
	755	return 1;
	756	default:
75818250	757	LOG("invalid request type (%u) received", request.type);
7a5ca864 FB	758	errno = EINVAL;
	759	return -1;
	760	}
	761
	762	TRACE("Request/Reply complete");
	763
	764	return 0;
	765	}