diff options
Diffstat (limited to 'qemu-nbd.c')
| -rw-r--r-- | qemu-nbd.c | 275 |
1 files changed, 275 insertions, 0 deletions
diff --git a/qemu-nbd.c b/qemu-nbd.c new file mode 100644 index 0000000000..3fb3d0c70d --- /dev/null +++ b/qemu-nbd.c @@ -0,0 +1,275 @@ +/*\ + * 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, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <qemu-common.h> +#include "block_int.h" +#include "nbd.h" + +#include <malloc.h> +#include <stdarg.h> +#include <stdio.h> +#include <getopt.h> +#include <err.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <netinet/tcp.h> +#include <arpa/inet.h> + +int verbose; + +static void usage(const char *name) +{ + printf( +"Usage: %s [OPTIONS] FILE\n" +"QEMU Disk Network Block Device Server\n" +"\n" +" -p, --port=PORT port to listen on (default `1024')\n" +" -o, --offset=OFFSET offset into the image\n" +" -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" +" -r, --read-only export read-only\n" +" -P, --partition=NUM only expose partition NUM\n" +" -v, --verbose display extra debugging information\n" +" -h, --help display this help and exit\n" +" -V, --version output version information and exit\n" +"\n" +"Report bugs to <anthony@codemonkey.ws>\n" + , name); +} + +static void version(const char *name) +{ + printf( +"qemu-nbd version 0.0.1\n" +"Written by Anthony Liguori.\n" +"\n" +"Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>.\n" +"This is free software; see the source for copying conditions. There is NO\n" +"warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" + ); +} + +struct partition_record +{ + uint8_t bootable; + uint8_t start_head; + uint32_t start_cylinder; + uint8_t start_sector; + uint8_t system; + uint8_t end_head; + uint8_t end_cylinder; + uint8_t end_sector; + uint32_t start_sector_abs; + uint32_t nb_sectors_abs; +}; + +static void read_partition(uint8_t *p, struct partition_record *r) +{ + r->bootable = p[0]; + r->start_head = p[1]; + r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300); + r->start_sector = p[2] & 0x3f; + r->system = p[4]; + r->end_head = p[5]; + r->end_cylinder = p[7] | ((p[6] << 2) & 0x300); + r->end_sector = p[6] & 0x3f; + r->start_sector_abs = p[8] | p[9] << 8 | p[10] << 16 | p[11] << 24; + r->nb_sectors_abs = p[12] | p[13] << 8 | p[14] << 16 | p[15] << 24; +} + +static int find_partition(BlockDriverState *bs, int partition, + off_t *offset, off_t *size) +{ + struct partition_record mbr[4]; + uint8_t data[512]; + int i; + int ext_partnum = 4; + + if (bdrv_read(bs, 0, data, 1)) + errx(EINVAL, "error while reading"); + + if (data[510] != 0x55 || data[511] != 0xaa) { + errno = -EINVAL; + return -1; + } + + for (i = 0; i < 4; i++) { + read_partition(&data[446 + 16 * i], &mbr[i]); + + if (!mbr[i].nb_sectors_abs) + continue; + + if (mbr[i].system == 0xF || mbr[i].system == 0x5) { + struct partition_record ext[4]; + uint8_t data1[512]; + int j; + + if (bdrv_read(bs, mbr[i].start_sector_abs, data1, 1)) + errx(EINVAL, "error while reading"); + + for (j = 0; j < 4; j++) { + read_partition(&data1[446 + 16 * j], &ext[j]); + if (!ext[j].nb_sectors_abs) + continue; + + if ((ext_partnum + j + 1) == partition) { + *offset = (uint64_t)ext[j].start_sector_abs << 9; + *size = (uint64_t)ext[j].nb_sectors_abs << 9; + return 0; + } + } + ext_partnum += 4; + } else if ((i + 1) == partition) { + *offset = (uint64_t)mbr[i].start_sector_abs << 9; + *size = (uint64_t)mbr[i].nb_sectors_abs << 9; + return 0; + } + } + + errno = -ENOENT; + return -1; +} + +int main(int argc, char **argv) +{ + BlockDriverState *bs; + off_t dev_offset = 0; + off_t offset = 0; + bool readonly = false; + const char *bindto = "0.0.0.0"; + int port = 1024; + int sock, csock; + struct sockaddr_in addr; + socklen_t addr_len = sizeof(addr); + off_t fd_size; + const char *sopt = "hVbo:p:rsP:v"; + struct option lopt[] = { + { "help", 0, 0, 'h' }, + { "version", 0, 0, 'V' }, + { "bind", 1, 0, 'b' }, + { "port", 1, 0, 'p' }, + { "offset", 1, 0, 'o' }, + { "read-only", 0, 0, 'r' }, + { "partition", 1, 0, 'P' }, + { "snapshot", 0, 0, 's' }, + { "verbose", 0, 0, 'v' }, + }; + int ch; + int opt_ind = 0; + int li; + char *end; + bool snapshot = false; + int partition = -1; + + while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { + switch (ch) { + case 's': + snapshot = true; + break; + case 'b': + bindto = optarg; + break; + case 'p': + li = strtol(optarg, &end, 0); + if (*end) { + errx(EINVAL, "Invalid port `%s'", optarg); + } + if (li < 1 || li > 65535) { + errx(EINVAL, "Port out of range `%s'", optarg); + } + port = (uint16_t)li; + break; + case 'o': + dev_offset = strtoll (optarg, &end, 0); + if (*end) { + errx(EINVAL, "Invalid offset `%s'", optarg); + } + if (dev_offset < 0) { + errx(EINVAL, "Offset must be positive `%s'", optarg); + } + break; + case 'r': + readonly = true; + break; + case 'P': + partition = strtol(optarg, &end, 0); + if (*end) + errx(EINVAL, "Invalid partition `%s'", optarg); + if (partition < 1 || partition > 8) + errx(EINVAL, "Invalid partition %d", partition); + break; + case 'v': + verbose = 1; + break; + case 'V': + version(argv[0]); + exit(0); + break; + case 'h': + usage(argv[0]); + exit(0); + break; + case '?': + errx(EINVAL, "Try `%s --help' for more information.", + argv[0]); + } + } + + if ((argc - optind) != 1) { + errx(EINVAL, "Invalid number of argument.\n" + "Try `%s --help' for more information.", + argv[0]); + } + + bdrv_init(); + + bs = bdrv_new("hda"); + if (bs == NULL) + return 1; + + if (bdrv_open(bs, argv[optind], snapshot) == -1) + return 1; + + fd_size = bs->total_sectors * 512; + + if (partition != -1 && + find_partition(bs, partition, &dev_offset, &fd_size)) + errx(errno, "Could not find partition %d", partition); + + sock = tcp_socket_incoming(bindto, port); + if (sock == -1) + return 1; + + csock = accept(sock, + (struct sockaddr *)&addr, + &addr_len); + if (csock == -1) + return 1; + + /* new fd_size is calculated by find_partition */ + if (nbd_negotiate(bs, csock, fd_size) == -1) + return 1; + + while (nbd_trip(bs, csock, fd_size, dev_offset, &offset, readonly) == 0); + + close(csock); + close(sock); + bdrv_close(bs); + + return 0; +} |