riscv
/
qemu
mirror of https://gitea.goldendeliverer.com/riscv/qemu.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
Browse Source

nbd: Handle fixed new-style clients. 

When this flag is set, the server tells the client that it can send another
option if the server received a request with an option that it doesn't
understand instead of directly closing the connection.

Also add link to the most up-to-date documentation.

Signed-off-by: Hani Benhabiles <kroosec@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
pull/12/head
Hani Benhabiles 12 years ago
committed by Paolo Bonzini
parent
27e5eae457
commit
f5076b5a75
2 changed files with 111 additions and 49 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 9
      include/block/nbd.h
  2. 151
      nbd.c

9
include/block/nbd.h
View File

@ -45,6 +45,15 @@ struct nbd_reply {
#define NBD_FLAG_ROTATIONAL (1 << 4) /* Use elevator algorithm - rotational media */
#define NBD_FLAG_SEND_TRIM (1 << 5) /* Send TRIM (discard) */
/* New-style global flags. */
#define NBD_FLAG_FIXED_NEWSTYLE (1 << 0) /* Fixed newstyle protocol. */
/* New-style client flags. */
#define NBD_FLAG_C_FIXED_NEWSTYLE (1 << 0) /* Fixed newstyle protocol. */
/* Reply types. */
#define NBD_REP_ERR_UNSUP ((1 << 31) | 1) /* Unknown option. */
#define NBD_CMD_MASK_COMMAND 0x0000ffff
#define NBD_CMD_FLAG_FUA (1 << 16)

151
nbd.c
View File

@ -56,7 +56,11 @@
__FILE__, __FUNCTION__, __LINE__, ## __VA_ARGS__); \
} while(0)
/* This is all part of the "official" NBD API */
/* This is all part of the "official" NBD API.
*
* The most up-to-date documentation is available at:
* https://github.com/yoe/nbd/blob/master/doc/proto.txt
*/
#define NBD_REQUEST_SIZE (4 + 4 + 8 + 8 + 4)
#define NBD_REPLY_SIZE (4 + 4 + 8)
@ -64,6 +68,7 @@
#define NBD_REPLY_MAGIC 0x67446698
#define NBD_OPTS_MAGIC 0x49484156454F5054LL
#define NBD_CLIENT_MAGIC 0x0000420281861253LL
#define NBD_REP_MAGIC 0x3e889045565a9LL
#define NBD_SET_SOCK _IO(0xab, 0)
#define NBD_SET_BLKSIZE _IO(0xab, 1)
@ -77,7 +82,8 @@
#define NBD_SET_TIMEOUT _IO(0xab, 9)
#define NBD_SET_FLAGS _IO(0xab, 10)
#define NBD_OPT_EXPORT_NAME (1 << 0)
#define NBD_OPT_EXPORT_NAME (1)
#define NBD_OPT_ABORT (2)
/* Definitions for opaque data types */
@ -215,59 +221,43 @@ static ssize_t write_sync(int fd, void *buffer, size_t size)
*/
static int nbd_receive_options(NBDClient *client)
static int nbd_send_rep(int csock, uint32_t type, uint32_t opt)
{
int csock = client->sock;
char name[256];
uint32_t tmp, length;
uint64_t magic;
int rc;
/* Client sends:
[ 0 .. 3] reserved (0)
[ 4 .. 11] NBD_OPTS_MAGIC
[12 .. 15] NBD_OPT_EXPORT_NAME
[16 .. 19] length
[20 .. xx] export name (length bytes)
*/
uint32_t len;
rc = -EINVAL;
if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) {
LOG("read failed");
goto fail;
magic = cpu_to_be64(NBD_REP_MAGIC);
if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) {
LOG("write failed (rep magic)");
return -EINVAL;
}
TRACE("Checking reserved");
if (tmp != 0) {
LOG("Bad reserved received");
goto fail;
opt = cpu_to_be32(opt);
if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) {
LOG("write failed (rep opt)");
return -EINVAL;
}
if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) {
LOG("read failed");
goto fail;
type = cpu_to_be32(type);
if (write_sync(csock, &type, sizeof(type)) != sizeof(type)) {
LOG("write failed (rep type)");
return -EINVAL;
}
TRACE("Checking reserved");
if (magic != be64_to_cpu(NBD_OPTS_MAGIC)) {
LOG("Bad magic received");
goto fail;
len = cpu_to_be32(0);
if (write_sync(csock, &len, sizeof(len)) != sizeof(len)) {
LOG("write failed (rep data length)");
return -EINVAL;
}
return 0;
}
if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) {
LOG("read failed");
goto fail;
}
TRACE("Checking option");
if (tmp != be32_to_cpu(NBD_OPT_EXPORT_NAME)) {
LOG("Bad option received");
goto fail;
}
static int nbd_handle_export_name(NBDClient *client, uint32_t length)
{
int rc = -EINVAL, csock = client->sock;
char name[256];
if (read_sync(csock, &length, sizeof(length)) != sizeof(length)) {
LOG("read failed");
goto fail;
}
/* Client sends:
[20 .. xx] export name (length bytes)
*/
TRACE("Checking length");
length = be32_to_cpu(length);
if (length > 255) {
LOG("Bad length received");
goto fail;
@ -286,13 +276,75 @@ static int nbd_receive_options(NBDClient *client)
QTAILQ_INSERT_TAIL(&client->exp->clients, client, next);
nbd_export_get(client->exp);
TRACE("Option negotiation succeeded.");
rc = 0;
fail:
return rc;
}
static int nbd_receive_options(NBDClient *client)
{
while (1) {
int csock = client->sock;
uint32_t tmp, length;
uint64_t magic;
/* Client sends:
[ 0 .. 3] client flags
[ 4 .. 11] NBD_OPTS_MAGIC
[12 .. 15] NBD option
[16 .. 19] length
... Rest of request
*/
if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) {
LOG("read failed");
return -EINVAL;
}
TRACE("Checking client flags");
tmp = be32_to_cpu(tmp);
if (tmp != 0 && tmp != NBD_FLAG_C_FIXED_NEWSTYLE) {
LOG("Bad client flags received");
return -EINVAL;
}
if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) {
LOG("read failed");
return -EINVAL;
}
TRACE("Checking opts magic");
if (magic != be64_to_cpu(NBD_OPTS_MAGIC)) {
LOG("Bad magic received");
return -EINVAL;
}
if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) {
LOG("read failed");
return -EINVAL;
}
if (read_sync(csock, &length, sizeof(length)) != sizeof(length)) {
LOG("read failed");
return -EINVAL;
}
length = be32_to_cpu(length);
TRACE("Checking option");
switch (be32_to_cpu(tmp)) {
case NBD_OPT_ABORT:
return -EINVAL;
case NBD_OPT_EXPORT_NAME:
return nbd_handle_export_name(client, length);
default:
tmp = be32_to_cpu(tmp);
LOG("Unsupported option 0x%x", tmp);
nbd_send_rep(client->sock, NBD_REP_ERR_UNSUP, tmp);
return -EINVAL;
}
}
}
static int nbd_send_negotiate(NBDClient *client)
{
int csock = client->sock;
@ -333,6 +385,7 @@ static int nbd_send_negotiate(NBDClient *client)
cpu_to_be16w((uint16_t*)(buf + 26), client->exp->nbdflags | myflags);
} else {
cpu_to_be64w((uint64_t*)(buf + 8), NBD_OPTS_MAGIC);
cpu_to_be16w((uint16_t *)(buf + 16), NBD_FLAG_FIXED_NEWSTYLE);
}
if (client->exp) {
@ -346,7 +399,7 @@ static int nbd_send_negotiate(NBDClient *client)
goto fail;
}
rc = nbd_receive_options(client);
if (rc < 0) {
if (rc != 0) {
LOG("option negotiation failed");
goto fail;
}
@ -1174,7 +1227,7 @@ NBDClient *nbd_client_new(NBDExport *exp, int csock,
client->refcount = 1;
client->exp = exp;
client->sock = csock;
if (nbd_send_negotiate(client) < 0) {
if (nbd_send_negotiate(client)) {
g_free(client);
return NULL;
}

Write Preview
Loading…
Cancel
Save