aboutsummaryrefslogtreecommitdiff
path: root/nbd
diff options
context:
space:
mode:
Diffstat (limited to 'nbd')
-rw-r--r--nbd/client.c283
-rw-r--r--nbd/common.c92
-rw-r--r--nbd/nbd-internal.h13
-rw-r--r--nbd/server.c304
-rw-r--r--nbd/trace-events25
5 files changed, 612 insertions, 105 deletions
diff --git a/nbd/client.c b/nbd/client.c
index 9c52b9b885..c3ee9f36b1 100644
--- a/nbd/client.c
+++ b/nbd/client.c
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2016 Red Hat, Inc.
+ * Copyright (C) 2016-2017 Red Hat, Inc.
* Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
*
* Network Block Device Client Side
@@ -104,7 +104,7 @@ static int nbd_send_option_request(QIOChannel *ioc, uint32_t opt,
if (len == -1) {
req.length = len = strlen(data);
}
- trace_nbd_send_option_request(opt, len);
+ trace_nbd_send_option_request(opt, nbd_opt_lookup(opt), len);
stq_be_p(&req.magic, NBD_OPTS_MAGIC);
stl_be_p(&req.option, opt);
@@ -154,7 +154,9 @@ static int nbd_receive_option_reply(QIOChannel *ioc, uint32_t opt,
be32_to_cpus(&reply->type);
be32_to_cpus(&reply->length);
- trace_nbd_receive_option_reply(reply->option, reply->type, reply->length);
+ trace_nbd_receive_option_reply(reply->option, nbd_opt_lookup(reply->option),
+ reply->type, nbd_rep_lookup(reply->type),
+ reply->length);
if (reply->magic != NBD_REP_MAGIC) {
error_setg(errp, "Unexpected option reply magic");
@@ -188,12 +190,16 @@ static int nbd_handle_reply_err(QIOChannel *ioc, nbd_opt_reply *reply,
if (reply->length) {
if (reply->length > NBD_MAX_BUFFER_SIZE) {
- error_setg(errp, "server's error message is too long");
+ error_setg(errp, "server error 0x%" PRIx32
+ " (%s) message is too long",
+ reply->type, nbd_rep_lookup(reply->type));
goto cleanup;
}
msg = g_malloc(reply->length + 1);
if (nbd_read(ioc, msg, reply->length, errp) < 0) {
- error_prepend(errp, "failed to read option error message");
+ error_prepend(errp, "failed to read option error 0x%" PRIx32
+ " (%s) message",
+ reply->type, nbd_rep_lookup(reply->type));
goto cleanup;
}
msg[reply->length] = '\0';
@@ -201,38 +207,48 @@ static int nbd_handle_reply_err(QIOChannel *ioc, nbd_opt_reply *reply,
switch (reply->type) {
case NBD_REP_ERR_UNSUP:
- trace_nbd_reply_err_unsup(reply->option);
+ trace_nbd_reply_err_unsup(reply->option, nbd_opt_lookup(reply->option));
result = 0;
goto cleanup;
case NBD_REP_ERR_POLICY:
- error_setg(errp, "Denied by server for option %" PRIx32,
- reply->option);
+ error_setg(errp, "Denied by server for option %" PRIx32 " (%s)",
+ reply->option, nbd_opt_lookup(reply->option));
break;
case NBD_REP_ERR_INVALID:
- error_setg(errp, "Invalid data length for option %" PRIx32,
- reply->option);
+ error_setg(errp, "Invalid data length for option %" PRIx32 " (%s)",
+ reply->option, nbd_opt_lookup(reply->option));
break;
case NBD_REP_ERR_PLATFORM:
- error_setg(errp, "Server lacks support for option %" PRIx32,
- reply->option);
+ error_setg(errp, "Server lacks support for option %" PRIx32 " (%s)",
+ reply->option, nbd_opt_lookup(reply->option));
break;
case NBD_REP_ERR_TLS_REQD:
- error_setg(errp, "TLS negotiation required before option %" PRIx32,
- reply->option);
+ error_setg(errp, "TLS negotiation required before option %" PRIx32
+ " (%s)", reply->option, nbd_opt_lookup(reply->option));
+ break;
+
+ case NBD_REP_ERR_UNKNOWN:
+ error_setg(errp, "Requested export not available for option %" PRIx32
+ " (%s)", reply->option, nbd_opt_lookup(reply->option));
break;
case NBD_REP_ERR_SHUTDOWN:
- error_setg(errp, "Server shutting down before option %" PRIx32,
- reply->option);
+ error_setg(errp, "Server shutting down before option %" PRIx32 " (%s)",
+ reply->option, nbd_opt_lookup(reply->option));
+ break;
+
+ case NBD_REP_ERR_BLOCK_SIZE_REQD:
+ error_setg(errp, "Server requires INFO_BLOCK_SIZE for option %" PRIx32
+ " (%s)", reply->option, nbd_opt_lookup(reply->option));
break;
default:
- error_setg(errp, "Unknown error code when asking for option %" PRIx32,
- reply->option);
+ error_setg(errp, "Unknown error code when asking for option %" PRIx32
+ " (%s)", reply->option, nbd_opt_lookup(reply->option));
break;
}
@@ -334,6 +350,165 @@ static int nbd_receive_list(QIOChannel *ioc, const char *want, bool *match,
}
+/* Returns -1 if NBD_OPT_GO proves the export @wantname cannot be
+ * used, 0 if NBD_OPT_GO is unsupported (fall back to NBD_OPT_LIST and
+ * NBD_OPT_EXPORT_NAME in that case), and > 0 if the export is good to
+ * go (with @info populated). */
+static int nbd_opt_go(QIOChannel *ioc, const char *wantname,
+ NBDExportInfo *info, Error **errp)
+{
+ nbd_opt_reply reply;
+ uint32_t len = strlen(wantname);
+ uint16_t type;
+ int error;
+ char *buf;
+
+ /* The protocol requires that the server send NBD_INFO_EXPORT with
+ * a non-zero flags (at least NBD_FLAG_HAS_FLAGS must be set); so
+ * flags still 0 is a witness of a broken server. */
+ info->flags = 0;
+
+ trace_nbd_opt_go_start(wantname);
+ buf = g_malloc(4 + len + 2 + 2 * info->request_sizes + 1);
+ stl_be_p(buf, len);
+ memcpy(buf + 4, wantname, len);
+ /* At most one request, everything else up to server */
+ stw_be_p(buf + 4 + len, info->request_sizes);
+ if (info->request_sizes) {
+ stw_be_p(buf + 4 + len + 2, NBD_INFO_BLOCK_SIZE);
+ }
+ if (nbd_send_option_request(ioc, NBD_OPT_GO,
+ 4 + len + 2 + 2 * info->request_sizes, buf,
+ errp) < 0) {
+ return -1;
+ }
+
+ while (1) {
+ if (nbd_receive_option_reply(ioc, NBD_OPT_GO, &reply, errp) < 0) {
+ return -1;
+ }
+ error = nbd_handle_reply_err(ioc, &reply, errp);
+ if (error <= 0) {
+ return error;
+ }
+ len = reply.length;
+
+ if (reply.type == NBD_REP_ACK) {
+ /* Server is done sending info and moved into transmission
+ phase, but make sure it sent flags */
+ if (len) {
+ error_setg(errp, "server sent invalid NBD_REP_ACK");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ if (!info->flags) {
+ error_setg(errp, "broken server omitted NBD_INFO_EXPORT");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ trace_nbd_opt_go_success();
+ return 1;
+ }
+ if (reply.type != NBD_REP_INFO) {
+ error_setg(errp, "unexpected reply type %" PRIx32
+ " (%s), expected %x",
+ reply.type, nbd_rep_lookup(reply.type), NBD_REP_INFO);
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ if (len < sizeof(type)) {
+ error_setg(errp, "NBD_REP_INFO length %" PRIu32 " is too short",
+ len);
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ if (nbd_read(ioc, &type, sizeof(type), errp) < 0) {
+ error_prepend(errp, "failed to read info type");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ len -= sizeof(type);
+ be16_to_cpus(&type);
+ switch (type) {
+ case NBD_INFO_EXPORT:
+ if (len != sizeof(info->size) + sizeof(info->flags)) {
+ error_setg(errp, "remaining export info len %" PRIu32
+ " is unexpected size", len);
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ if (nbd_read(ioc, &info->size, sizeof(info->size), errp) < 0) {
+ error_prepend(errp, "failed to read info size");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ be64_to_cpus(&info->size);
+ if (nbd_read(ioc, &info->flags, sizeof(info->flags), errp) < 0) {
+ error_prepend(errp, "failed to read info flags");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ be16_to_cpus(&info->flags);
+ trace_nbd_receive_negotiate_size_flags(info->size, info->flags);
+ break;
+
+ case NBD_INFO_BLOCK_SIZE:
+ if (len != sizeof(info->min_block) * 3) {
+ error_setg(errp, "remaining export info len %" PRIu32
+ " is unexpected size", len);
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ if (nbd_read(ioc, &info->min_block, sizeof(info->min_block),
+ errp) < 0) {
+ error_prepend(errp, "failed to read info minimum block size");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ be32_to_cpus(&info->min_block);
+ if (!is_power_of_2(info->min_block)) {
+ error_setg(errp, "server minimum block size %" PRId32
+ "is not a power of two", info->min_block);
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ if (nbd_read(ioc, &info->opt_block, sizeof(info->opt_block),
+ errp) < 0) {
+ error_prepend(errp, "failed to read info preferred block size");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ be32_to_cpus(&info->opt_block);
+ if (!is_power_of_2(info->opt_block) ||
+ info->opt_block < info->min_block) {
+ error_setg(errp, "server preferred block size %" PRId32
+ "is not valid", info->opt_block);
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ if (nbd_read(ioc, &info->max_block, sizeof(info->max_block),
+ errp) < 0) {
+ error_prepend(errp, "failed to read info maximum block size");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ be32_to_cpus(&info->max_block);
+ trace_nbd_opt_go_info_block_size(info->min_block, info->opt_block,
+ info->max_block);
+ break;
+
+ default:
+ trace_nbd_opt_go_info_unknown(type, nbd_info_lookup(type));
+ if (nbd_drop(ioc, len, errp) < 0) {
+ error_prepend(errp, "Failed to read info payload");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
+ break;
+ }
+ }
+}
+
/* Return -1 on failure, 0 if wantname is an available export. */
static int nbd_receive_query_exports(QIOChannel *ioc,
const char *wantname,
@@ -425,13 +600,13 @@ static QIOChannel *nbd_receive_starttls(QIOChannel *ioc,
}
-int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint16_t *flags,
+int nbd_receive_negotiate(QIOChannel *ioc, const char *name,
QCryptoTLSCreds *tlscreds, const char *hostname,
- QIOChannel **outioc,
- off_t *size, Error **errp)
+ QIOChannel **outioc, NBDExportInfo *info,
+ Error **errp)
{
char buf[256];
- uint64_t magic, s;
+ uint64_t magic;
int rc;
bool zeroes = true;
@@ -515,11 +690,25 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint16_t *flags,
name = "";
}
if (fixedNewStyle) {
+ int result;
+
+ /* Try NBD_OPT_GO first - if it works, we are done (it
+ * also gives us a good message if the server requires
+ * TLS). If it is not available, fall back to
+ * NBD_OPT_LIST for nicer error messages about a missing
+ * export, then use NBD_OPT_EXPORT_NAME. */
+ result = nbd_opt_go(ioc, name, info, errp);
+ if (result < 0) {
+ goto fail;
+ }
+ if (result > 0) {
+ return 0;
+ }
/* Check our desired export is present in the
* server export list. Since NBD_OPT_EXPORT_NAME
* cannot return an error message, running this
- * query gives us good error reporting if the
- * server required TLS
+ * query gives us better error reporting if the
+ * export name is not available.
*/
if (nbd_receive_query_exports(ioc, name, errp) < 0) {
goto fail;
@@ -532,17 +721,17 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint16_t *flags,
}
/* Read the response */
- if (nbd_read(ioc, &s, sizeof(s), errp) < 0) {
+ if (nbd_read(ioc, &info->size, sizeof(info->size), errp) < 0) {
error_prepend(errp, "Failed to read export length");
goto fail;
}
- *size = be64_to_cpu(s);
+ be64_to_cpus(&info->size);
- if (nbd_read(ioc, flags, sizeof(*flags), errp) < 0) {
+ if (nbd_read(ioc, &info->flags, sizeof(info->flags), errp) < 0) {
error_prepend(errp, "Failed to read export flags");
goto fail;
}
- be16_to_cpus(flags);
+ be16_to_cpus(&info->flags);
} else if (magic == NBD_CLIENT_MAGIC) {
uint32_t oldflags;
@@ -555,11 +744,11 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint16_t *flags,
goto fail;
}
- if (nbd_read(ioc, &s, sizeof(s), errp) < 0) {
+ if (nbd_read(ioc, &info->size, sizeof(info->size), errp) < 0) {
error_prepend(errp, "Failed to read export length");
goto fail;
}
- *size = be64_to_cpu(s);
+ be64_to_cpus(&info->size);
if (nbd_read(ioc, &oldflags, sizeof(oldflags), errp) < 0) {
error_prepend(errp, "Failed to read export flags");
@@ -570,13 +759,13 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint16_t *flags,
error_setg(errp, "Unexpected export flags %0x" PRIx32, oldflags);
goto fail;
}
- *flags = oldflags;
+ info->flags = oldflags;
} else {
error_setg(errp, "Bad magic received");
goto fail;
}
- trace_nbd_receive_negotiate_size_flags(*size, *flags);
+ trace_nbd_receive_negotiate_size_flags(info->size, info->flags);
if (zeroes && nbd_drop(ioc, 124, errp) < 0) {
error_prepend(errp, "Failed to read reserved block");
goto fail;
@@ -588,13 +777,19 @@ fail:
}
#ifdef __linux__
-int nbd_init(int fd, QIOChannelSocket *sioc, uint16_t flags, off_t size,
+int nbd_init(int fd, QIOChannelSocket *sioc, NBDExportInfo *info,
Error **errp)
{
- unsigned long sectors = size / BDRV_SECTOR_SIZE;
- if (size / BDRV_SECTOR_SIZE != sectors) {
- error_setg(errp, "Export size %lld too large for 32-bit kernel",
- (long long) size);
+ unsigned long sector_size = MAX(BDRV_SECTOR_SIZE, info->min_block);
+ unsigned long sectors = info->size / sector_size;
+
+ /* FIXME: Once the kernel module is patched to honor block sizes,
+ * and to advertise that fact to user space, we should update the
+ * hand-off to the kernel to use any block sizes we learned. */
+ assert(!info->request_sizes);
+ if (info->size / sector_size != sectors) {
+ error_setg(errp, "Export size %" PRIu64 " too large for 32-bit kernel",
+ info->size);
return -E2BIG;
}
@@ -606,17 +801,17 @@ int nbd_init(int fd, QIOChannelSocket *sioc, uint16_t flags, off_t size,
return -serrno;
}
- trace_nbd_init_set_block_size(BDRV_SECTOR_SIZE);
+ trace_nbd_init_set_block_size(sector_size);
- if (ioctl(fd, NBD_SET_BLKSIZE, (unsigned long)BDRV_SECTOR_SIZE) < 0) {
+ if (ioctl(fd, NBD_SET_BLKSIZE, sector_size) < 0) {
int serrno = errno;
error_setg(errp, "Failed setting NBD block size");
return -serrno;
}
trace_nbd_init_set_size(sectors);
- if (size % BDRV_SECTOR_SIZE) {
- trace_nbd_init_trailing_bytes(size % BDRV_SECTOR_SIZE);
+ if (info->size % sector_size) {
+ trace_nbd_init_trailing_bytes(info->size % sector_size);
}
if (ioctl(fd, NBD_SET_SIZE_BLOCKS, sectors) < 0) {
@@ -625,9 +820,9 @@ int nbd_init(int fd, QIOChannelSocket *sioc, uint16_t flags, off_t size,
return -serrno;
}
- if (ioctl(fd, NBD_SET_FLAGS, (unsigned long) flags) < 0) {
+ if (ioctl(fd, NBD_SET_FLAGS, (unsigned long) info->flags) < 0) {
if (errno == ENOTTY) {
- int read_only = (flags & NBD_FLAG_READ_ONLY) != 0;
+ int read_only = (info->flags & NBD_FLAG_READ_ONLY) != 0;
trace_nbd_init_set_readonly();
if (ioctl(fd, BLKROSET, (unsigned long) &read_only) < 0) {
@@ -685,7 +880,7 @@ int nbd_disconnect(int fd)
}
#else
-int nbd_init(int fd, QIOChannelSocket *ioc, uint16_t flags, off_t size,
+int nbd_init(int fd, QIOChannelSocket *ioc, NBDExportInfo *info,
Error **errp)
{
error_setg(errp, "nbd_init is only supported on Linux");
diff --git a/nbd/common.c b/nbd/common.c
index 4dab41e2c0..a2f28f2eec 100644
--- a/nbd/common.c
+++ b/nbd/common.c
@@ -101,3 +101,95 @@ void nbd_tls_handshake(QIOTask *task,
data->complete = true;
g_main_loop_quit(data->loop);
}
+
+
+const char *nbd_opt_lookup(uint32_t opt)
+{
+ switch (opt) {
+ case NBD_OPT_EXPORT_NAME:
+ return "export name";
+ case NBD_OPT_ABORT:
+ return "abort";
+ case NBD_OPT_LIST:
+ return "list";
+ case NBD_OPT_STARTTLS:
+ return "starttls";
+ case NBD_OPT_INFO:
+ return "info";
+ case NBD_OPT_GO:
+ return "go";
+ case NBD_OPT_STRUCTURED_REPLY:
+ return "structured reply";
+ default:
+ return "<unknown>";
+ }
+}
+
+
+const char *nbd_rep_lookup(uint32_t rep)
+{
+ switch (rep) {
+ case NBD_REP_ACK:
+ return "ack";
+ case NBD_REP_SERVER:
+ return "server";
+ case NBD_REP_INFO:
+ return "info";
+ case NBD_REP_ERR_UNSUP:
+ return "unsupported";
+ case NBD_REP_ERR_POLICY:
+ return "denied by policy";
+ case NBD_REP_ERR_INVALID:
+ return "invalid";
+ case NBD_REP_ERR_PLATFORM:
+ return "platform lacks support";
+ case NBD_REP_ERR_TLS_REQD:
+ return "TLS required";
+ case NBD_REP_ERR_UNKNOWN:
+ return "export unknown";
+ case NBD_REP_ERR_SHUTDOWN:
+ return "server shutting down";
+ case NBD_REP_ERR_BLOCK_SIZE_REQD:
+ return "block size required";
+ default:
+ return "<unknown>";
+ }
+}
+
+
+const char *nbd_info_lookup(uint16_t info)
+{
+ switch (info) {
+ case NBD_INFO_EXPORT:
+ return "export";
+ case NBD_INFO_NAME:
+ return "name";
+ case NBD_INFO_DESCRIPTION:
+ return "description";
+ case NBD_INFO_BLOCK_SIZE:
+ return "block size";
+ default:
+ return "<unknown>";
+ }
+}
+
+
+const char *nbd_cmd_lookup(uint16_t cmd)
+{
+ switch (cmd) {
+ case NBD_CMD_READ:
+ return "read";
+ case NBD_CMD_WRITE:
+ return "write";
+ case NBD_CMD_DISC:
+ return "discard";
+ case NBD_CMD_FLUSH:
+ return "flush";
+ case NBD_CMD_TRIM:
+ return "trim";
+ case NBD_CMD_WRITE_ZEROES:
+ return "write zeroes";
+ default:
+ return "<unknown>";
+ }
+}
diff --git a/nbd/nbd-internal.h b/nbd/nbd-internal.h
index cf6ecbf358..4065bc68ac 100644
--- a/nbd/nbd-internal.h
+++ b/nbd/nbd-internal.h
@@ -37,8 +37,11 @@
* https://github.com/yoe/nbd/blob/master/doc/proto.md
*/
+/* Size of all NBD_OPT_*, without payload */
#define NBD_REQUEST_SIZE (4 + 2 + 2 + 8 + 8 + 4)
+/* Size of all NBD_REP_* sent in answer to most NBD_OPT_*, without payload */
#define NBD_REPLY_SIZE (4 + 4 + 8)
+
#define NBD_REQUEST_MAGIC 0x25609513
#define NBD_REPLY_MAGIC 0x67446698
#define NBD_OPTS_MAGIC 0x49484156454F5054LL
@@ -57,12 +60,6 @@
#define NBD_SET_TIMEOUT _IO(0xab, 9)
#define NBD_SET_FLAGS _IO(0xab, 10)
-#define NBD_OPT_EXPORT_NAME (1)
-#define NBD_OPT_ABORT (2)
-#define NBD_OPT_LIST (3)
-#define NBD_OPT_PEEK_EXPORT (4)
-#define NBD_OPT_STARTTLS (5)
-
/* NBD errors are based on errno numbers, so there is a 1:1 mapping,
* but only a limited set of errno values is specified in the protocol.
* Everything else is squashed to EINVAL.
@@ -133,6 +130,10 @@ struct NBDTLSHandshakeData {
void nbd_tls_handshake(QIOTask *task,
void *opaque);
+const char *nbd_opt_lookup(uint32_t opt);
+const char *nbd_rep_lookup(uint32_t rep);
+const char *nbd_info_lookup(uint16_t info);
+const char *nbd_cmd_lookup(uint16_t info);
int nbd_drop(QIOChannel *ioc, size_t size, Error **errp);
diff --git a/nbd/server.c b/nbd/server.c
index 9b0c588146..49ed57455c 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2016 Red Hat, Inc.
+ * Copyright (C) 2016-2017 Red Hat, Inc.
* Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
*
* Network Block Device Server Side
@@ -84,7 +84,6 @@ struct NBDClient {
int refcount;
void (*close_fn)(NBDClient *client, bool negotiated);
- bool no_zeroes;
NBDExport *exp;
QCryptoTLSCreds *tlscreds;
char *tlsaclname;
@@ -139,8 +138,10 @@ static int nbd_negotiate_send_rep_len(QIOChannel *ioc, uint32_t type,
{
uint64_t magic;
- trace_nbd_negotiate_send_rep_len(opt, type, len);
+ trace_nbd_negotiate_send_rep_len(opt, nbd_opt_lookup(opt),
+ type, nbd_rep_lookup(type), len);
+ assert(len < NBD_MAX_BUFFER_SIZE);
magic = cpu_to_be64(NBD_REP_MAGIC);
if (nbd_write(ioc, &magic, sizeof(magic), errp) < 0) {
error_prepend(errp, "write failed (rep magic): ");
@@ -275,10 +276,16 @@ static int nbd_negotiate_handle_list(NBDClient *client, uint32_t length,
return nbd_negotiate_send_rep(client->ioc, NBD_REP_ACK, NBD_OPT_LIST, errp);
}
+/* Send a reply to NBD_OPT_EXPORT_NAME.
+ * Return -errno on error, 0 on success. */
static int nbd_negotiate_handle_export_name(NBDClient *client, uint32_t length,
+ uint16_t myflags, bool no_zeroes,
Error **errp)
{
char name[NBD_MAX_NAME_SIZE + 1];
+ char buf[8 + 4 + 124] = "";
+ size_t len;
+ int ret;
/* Client sends:
[20 .. xx] export name (length bytes)
@@ -302,12 +309,219 @@ static int nbd_negotiate_handle_export_name(NBDClient *client, uint32_t length,
return -EINVAL;
}
+ trace_nbd_negotiate_new_style_size_flags(client->exp->size,
+ client->exp->nbdflags | myflags);
+ stq_be_p(buf, client->exp->size);
+ stw_be_p(buf + 8, client->exp->nbdflags | myflags);
+ len = no_zeroes ? 10 : sizeof(buf);
+ ret = nbd_write(client->ioc, buf, len, errp);
+ if (ret < 0) {
+ error_prepend(errp, "write failed: ");
+ return ret;
+ }
+
QTAILQ_INSERT_TAIL(&client->exp->clients, client, next);
nbd_export_get(client->exp);
return 0;
}
+/* Send a single NBD_REP_INFO, with a buffer @buf of @length bytes.
+ * The buffer does NOT include the info type prefix.
+ * Return -errno on error, 0 if ready to send more. */
+static int nbd_negotiate_send_info(NBDClient *client, uint32_t opt,
+ uint16_t info, uint32_t length, void *buf,
+ Error **errp)
+{
+ int rc;
+
+ trace_nbd_negotiate_send_info(info, nbd_info_lookup(info), length);
+ rc = nbd_negotiate_send_rep_len(client->ioc, NBD_REP_INFO, opt,
+ sizeof(info) + length, errp);
+ if (rc < 0) {
+ return rc;
+ }
+ cpu_to_be16s(&info);
+ if (nbd_write(client->ioc, &info, sizeof(info), errp) < 0) {
+ return -EIO;
+ }
+ if (nbd_write(client->ioc, buf, length, errp) < 0) {
+ return -EIO;
+ }
+ return 0;
+}
+
+/* Handle NBD_OPT_INFO and NBD_OPT_GO.
+ * Return -errno on error, 0 if ready for next option, and 1 to move
+ * into transmission phase. */
+static int nbd_negotiate_handle_info(NBDClient *client, uint32_t length,
+ uint32_t opt, uint16_t myflags,
+ Error **errp)
+{
+ int rc;
+ char name[NBD_MAX_NAME_SIZE + 1];
+ NBDExport *exp;
+ uint16_t requests;
+ uint16_t request;
+ uint32_t namelen;
+ bool sendname = false;
+ bool blocksize = false;
+ uint32_t sizes[3];
+ char buf[sizeof(uint64_t) + sizeof(uint16_t)];
+ const char *msg;
+
+ /* Client sends:
+ 4 bytes: L, name length (can be 0)
+ L bytes: export name
+ 2 bytes: N, number of requests (can be 0)
+ N * 2 bytes: N requests
+ */
+ if (length < sizeof(namelen) + sizeof(requests)) {
+ msg = "overall request too short";
+ goto invalid;
+ }
+ if (nbd_read(client->ioc, &namelen, sizeof(namelen), errp) < 0) {
+ return -EIO;
+ }
+ be32_to_cpus(&namelen);
+ length -= sizeof(namelen);
+ if (namelen > length - sizeof(requests) || (length - namelen) % 2) {
+ msg = "name length is incorrect";
+ goto invalid;
+ }
+ if (nbd_read(client->ioc, name, namelen, errp) < 0) {
+ return -EIO;
+ }
+ name[namelen] = '\0';
+ length -= namelen;
+ trace_nbd_negotiate_handle_export_name_request(name);
+
+ if (nbd_read(client->ioc, &requests, sizeof(requests), errp) < 0) {
+ return -EIO;
+ }
+ be16_to_cpus(&requests);
+ length -= sizeof(requests);
+ trace_nbd_negotiate_handle_info_requests(requests);
+ if (requests != length / sizeof(request)) {
+ msg = "incorrect number of requests for overall length";
+ goto invalid;
+ }
+ while (requests--) {
+ if (nbd_read(client->ioc, &request, sizeof(request), errp) < 0) {
+ return -EIO;
+ }
+ be16_to_cpus(&request);
+ length -= sizeof(request);
+ trace_nbd_negotiate_handle_info_request(request,
+ nbd_info_lookup(request));
+ /* We care about NBD_INFO_NAME and NBD_INFO_BLOCK_SIZE;
+ * everything else is either a request we don't know or
+ * something we send regardless of request */
+ switch (request) {
+ case NBD_INFO_NAME:
+ sendname = true;
+ break;
+ case NBD_INFO_BLOCK_SIZE:
+ blocksize = true;
+ break;
+ }
+ }
+
+ exp = nbd_export_find(name);
+ if (!exp) {
+ return nbd_negotiate_send_rep_err(client->ioc, NBD_REP_ERR_UNKNOWN,
+ opt, errp, "export '%s' not present",
+ name);
+ }
+
+ /* Don't bother sending NBD_INFO_NAME unless client requested it */
+ if (sendname) {
+ rc = nbd_negotiate_send_info(client, opt, NBD_INFO_NAME, length, name,
+ errp);
+ if (rc < 0) {
+ return rc;
+ }
+ }
+
+ /* Send NBD_INFO_DESCRIPTION only if available, regardless of
+ * client request */
+ if (exp->description) {
+ size_t len = strlen(exp->description);
+
+ rc = nbd_negotiate_send_info(client, opt, NBD_INFO_DESCRIPTION,
+ len, exp->description, errp);
+ if (rc < 0) {
+ return rc;
+ }
+ }
+
+ /* Send NBD_INFO_BLOCK_SIZE always, but tweak the minimum size
+ * according to whether the client requested it, and according to
+ * whether this is OPT_INFO or OPT_GO. */
+ /* minimum - 1 for back-compat, or 512 if client is new enough.
+ * TODO: consult blk_bs(blk)->bl.request_alignment? */
+ sizes[0] = (opt == NBD_OPT_INFO || blocksize) ? BDRV_SECTOR_SIZE : 1;
+ /* preferred - Hard-code to 4096 for now.
+ * TODO: is blk_bs(blk)->bl.opt_transfer appropriate? */
+ sizes[1] = 4096;
+ /* maximum - At most 32M, but smaller as appropriate. */
+ sizes[2] = MIN(blk_get_max_transfer(exp->blk), NBD_MAX_BUFFER_SIZE);
+ trace_nbd_negotiate_handle_info_block_size(sizes[0], sizes[1], sizes[2]);
+ cpu_to_be32s(&sizes[0]);
+ cpu_to_be32s(&sizes[1]);
+ cpu_to_be32s(&sizes[2]);
+ rc = nbd_negotiate_send_info(client, opt, NBD_INFO_BLOCK_SIZE,
+ sizeof(sizes), sizes, errp);
+ if (rc < 0) {
+ return rc;
+ }
+
+ /* Send NBD_INFO_EXPORT always */
+ trace_nbd_negotiate_new_style_size_flags(exp->size,
+ exp->nbdflags | myflags);
+ stq_be_p(buf, exp->size);
+ stw_be_p(buf + 8, exp->nbdflags | myflags);
+ rc = nbd_negotiate_send_info(client, opt, NBD_INFO_EXPORT,
+ sizeof(buf), buf, errp);
+ if (rc < 0) {
+ return rc;
+ }
+
+ /* If the client is just asking for NBD_OPT_INFO, but forgot to
+ * request block sizes, return an error.
+ * TODO: consult blk_bs(blk)->request_align, and only error if it
+ * is not 1? */
+ if (opt == NBD_OPT_INFO && !blocksize) {
+ return nbd_negotiate_send_rep_err(client->ioc,
+ NBD_REP_ERR_BLOCK_SIZE_REQD, opt,
+ errp,
+ "request NBD_INFO_BLOCK_SIZE to "
+ "use this export");
+ }
+
+ /* Final reply */
+ rc = nbd_negotiate_send_rep(client->ioc, NBD_REP_ACK, opt, errp);
+ if (rc < 0) {
+ return rc;
+ }
+
+ if (opt == NBD_OPT_GO) {
+ client->exp = exp;
+ QTAILQ_INSERT_TAIL(&client->exp->clients, client, next);
+ nbd_export_get(client->exp);
+ rc = 1;
+ }
+ return rc;
+
+ invalid:
+ if (nbd_drop(client->ioc, length, errp) < 0) {
+ return -EIO;
+ }
+ return nbd_negotiate_send_rep_err(client->ioc, NBD_REP_ERR_INVALID, opt,
+ errp, "%s", msg);
+}
+
+
/* Handle NBD_OPT_STARTTLS. Return NULL to drop connection, or else the
* new channel for all further (now-encrypted) communication. */
static QIOChannel *nbd_negotiate_handle_starttls(NBDClient *client,
@@ -365,22 +579,25 @@ static QIOChannel *nbd_negotiate_handle_starttls(NBDClient *client,
}
/* nbd_negotiate_options
- * Process all NBD_OPT_* client option commands.
+ * Process all NBD_OPT_* client option commands, during fixed newstyle
+ * negotiation.
* Return:
* -errno on error, errp is set
* 0 on successful negotiation, errp is not set
* 1 if client sent NBD_OPT_ABORT, i.e. on valid disconnect,
* errp is not set
*/
-static int nbd_negotiate_options(NBDClient *client, Error **errp)
+static int nbd_negotiate_options(NBDClient *client, uint16_t myflags,
+ Error **errp)
{
uint32_t flags;
bool fixedNewstyle = false;
- Error *local_err = NULL;
+ bool no_zeroes = false;
/* Client sends:
[ 0 .. 3] client flags
+ Then we loop until NBD_OPT_EXPORT_NAME or NBD_OPT_GO:
[ 0 .. 7] NBD_OPTS_MAGIC
[ 8 .. 11] NBD option
[12 .. 15] Data length
@@ -396,21 +613,19 @@ static int nbd_negotiate_options(NBDClient *client, Error **errp)
error_prepend(errp, "read failed: ");
return -EIO;
}
- trace_nbd_negotiate_options_flags();
be32_to_cpus(&flags);
+ trace_nbd_negotiate_options_flags(flags);
if (flags & NBD_FLAG_C_FIXED_NEWSTYLE) {
- trace_nbd_negotiate_options_newstyle();
fixedNewstyle = true;
flags &= ~NBD_FLAG_C_FIXED_NEWSTYLE;
}
if (flags & NBD_FLAG_C_NO_ZEROES) {
- trace_nbd_negotiate_options_no_zeroes();
- client->no_zeroes = true;
+ no_zeroes = true;
flags &= ~NBD_FLAG_C_NO_ZEROES;
}
if (flags != 0) {
error_setg(errp, "Unknown client flags 0x%" PRIx32 " received", flags);
- return -EIO;
+ return -EINVAL;
}
while (1) {
@@ -442,7 +657,8 @@ static int nbd_negotiate_options(NBDClient *client, Error **errp)
}
length = be32_to_cpu(length);
- trace_nbd_negotiate_options_check_option(option);
+ trace_nbd_negotiate_options_check_option(option,
+ nbd_opt_lookup(option));
if (client->tlscreds &&
client->ioc == (QIOChannel *)client->sioc) {
QIOChannel *tioc;
@@ -479,7 +695,9 @@ static int nbd_negotiate_options(NBDClient *client, Error **errp)
if (ret < 0) {
return ret;
}
- /* Let the client keep trying, unless they asked to quit */
+ /* Let the client keep trying, unless they asked to
+ * quit. In this mode, we've already sent an error, so
+ * we can't ack the abort. */
if (option == NBD_OPT_ABORT) {
return 1;
}
@@ -498,19 +716,26 @@ static int nbd_negotiate_options(NBDClient *client, Error **errp)
/* NBD spec says we must try to reply before
* disconnecting, but that we must also tolerate
* guests that don't wait for our reply. */
- nbd_negotiate_send_rep(client->ioc, NBD_REP_ACK, option,
- &local_err);
-
- if (local_err != NULL) {
- const char *error = error_get_pretty(local_err);
- trace_nbd_opt_abort_reply_failed(error);
- error_free(local_err);
- }
-
+ nbd_negotiate_send_rep(client->ioc, NBD_REP_ACK, option, NULL);
return 1;
case NBD_OPT_EXPORT_NAME:
- return nbd_negotiate_handle_export_name(client, length, errp);
+ return nbd_negotiate_handle_export_name(client, length,
+ myflags, no_zeroes,
+ errp);
+
+ case NBD_OPT_INFO:
+ case NBD_OPT_GO:
+ ret = nbd_negotiate_handle_info(client, length, option,
+ myflags, errp);
+ if (ret == 1) {
+ assert(option == NBD_OPT_GO);
+ return 0;
+ }
+ if (ret) {
+ return ret;
+ }
+ break;
case NBD_OPT_STARTTLS:
if (nbd_drop(client->ioc, length, errp) < 0) {
@@ -539,8 +764,8 @@ static int nbd_negotiate_options(NBDClient *client, Error **errp)
NBD_REP_ERR_UNSUP,
option, errp,
"Unsupported option 0x%"
- PRIx32,
- option);
+ PRIx32 " (%s)", option,
+ nbd_opt_lookup(option));
if (ret < 0) {
return ret;
}
@@ -553,10 +778,13 @@ static int nbd_negotiate_options(NBDClient *client, Error **errp)
*/
switch (option) {
case NBD_OPT_EXPORT_NAME:
- return nbd_negotiate_handle_export_name(client, length, errp);
+ return nbd_negotiate_handle_export_name(client, length,
+ myflags, no_zeroes,
+ errp);
default:
- error_setg(errp, "Unsupported option 0x%" PRIx32, option);
+ error_setg(errp, "Unsupported option 0x%" PRIx32 " (%s)",
+ option, nbd_opt_lookup(option));
return -EINVAL;
}
}
@@ -578,7 +806,6 @@ static coroutine_fn int nbd_negotiate(NBDClient *client, Error **errp)
NBD_FLAG_SEND_FLUSH | NBD_FLAG_SEND_FUA |
NBD_FLAG_SEND_WRITE_ZEROES);
bool oldStyle;
- size_t len;
/* Old style negotiation header without options
[ 0 .. 7] passwd ("NBDMAGIC")
@@ -592,10 +819,7 @@ static coroutine_fn int nbd_negotiate(NBDClient *client, Error **errp)
[ 0 .. 7] passwd ("NBDMAGIC")
[ 8 .. 15] magic (NBD_OPTS_MAGIC)
[16 .. 17] server flags (0)
- ....options sent....
- [18 .. 25] size
- [26 .. 27] export flags
- [28 .. 151] reserved (0, omit if no_zeroes)
+ ....options sent, ending in NBD_OPT_EXPORT_NAME or NBD_OPT_GO....
*/
qio_channel_set_blocking(client->ioc, false, NULL);
@@ -624,24 +848,13 @@ static coroutine_fn int nbd_negotiate(NBDClient *client, Error **errp)
error_prepend(errp, "write failed: ");
return -EINVAL;
}
- ret = nbd_negotiate_options(client, errp);
+ ret = nbd_negotiate_options(client, myflags, errp);
if (ret != 0) {
if (ret < 0) {
error_prepend(errp, "option negotiation failed: ");
}
return ret;
}
-
- trace_nbd_negotiate_new_style_size_flags(
- client->exp->size, client->exp->nbdflags | myflags);
- stq_be_p(buf + 18, client->exp->size);
- stw_be_p(buf + 26, client->exp->nbdflags | myflags);
- len = client->no_zeroes ? 10 : sizeof(buf) - 18;
- ret = nbd_write(client->ioc, buf + 18, len, errp);
- if (ret < 0) {
- error_prepend(errp, "write failed: ");
- return ret;
- }
}
trace_nbd_negotiate_success();
@@ -1040,7 +1253,8 @@ static int nbd_co_receive_request(NBDRequestData *req, NBDRequest *request,
return -EIO;
}
- trace_nbd_co_receive_request_decode_type(request->handle, request->type);
+ trace_nbd_co_receive_request_decode_type(request->handle, request->type,
+ nbd_cmd_lookup(request->type));
if (request->type != NBD_CMD_WRITE) {
/* No payload, we are ready to read the next request. */
diff --git a/nbd/trace-events b/nbd/trace-events
index 4b233b8510..f5024d85a1 100644
--- a/nbd/trace-events
+++ b/nbd/trace-events
@@ -1,8 +1,12 @@
# nbd/client.c
nbd_unknown_error(int err) "Squashing unexpected error %d to EINVAL"
-nbd_send_option_request(uint32_t opt, uint32_t len) "Sending option request %" PRIu32", len %" PRIu32
-nbd_receive_option_reply(uint32_t option, uint32_t type, uint32_t length) "Received option reply %" PRIx32", type %" PRIx32", len %" PRIu32
-nbd_reply_err_unsup(uint32_t option) "server doesn't understand request %" PRIx32 ", attempting fallback"
+nbd_send_option_request(uint32_t opt, const char *name, uint32_t len) "Sending option request %" PRIu32" (%s), len %" PRIu32
+nbd_receive_option_reply(uint32_t option, const char *optname, uint32_t type, const char *typename, uint32_t length) "Received option reply %" PRIx32" (%s), type %" PRIx32" (%s), len %" PRIu32
+nbd_reply_err_unsup(uint32_t option, const char *name) "server doesn't understand request %" PRIx32 " (%s), attempting fallback"
+nbd_opt_go_start(const char *name) "Attempting NBD_OPT_GO for export '%s'"
+nbd_opt_go_success(void) "Export is good to go"
+nbd_opt_go_info_unknown(int info, const char *name) "Ignoring unknown info %d (%s)"
+nbd_opt_go_info_block_size(uint32_t minimum, uint32_t preferred, uint32_t maximum) "Block sizes are 0x%" PRIx32 ", 0x%" PRIx32 ", 0x%" PRIx32
nbd_receive_query_exports_start(const char *wantname) "Querying export list for '%s'"
nbd_receive_query_exports_success(const char *wantname) "Found desired export name '%s'"
nbd_receive_starttls_request(void) "Requesting TLS from server"
@@ -28,19 +32,20 @@ nbd_send_request(uint64_t from, uint32_t len, uint64_t handle, uint16_t flags, u
nbd_receive_reply(uint32_t magic, int32_t error, uint64_t handle) "Got reply: { magic = 0x%" PRIx32 ", .error = % " PRId32 ", handle = %" PRIu64" }"
# nbd/server.c
-nbd_negotiate_send_rep_len(uint32_t opt, uint32_t type, uint32_t len) "Reply opt=%" PRIx32 " type=%" PRIx32 " len=%" PRIu32
+nbd_negotiate_send_rep_len(uint32_t opt, const char *optname, uint32_t type, const char *typename, uint32_t len) "Reply opt=%" PRIx32 " (%s), type=%" PRIx32 " (%s), len=%" PRIu32
nbd_negotiate_send_rep_err(const char *msg) "sending error message \"%s\""
nbd_negotiate_send_rep_list(const char *name, const char *desc) "Advertising export name '%s' description '%s'"
nbd_negotiate_handle_export_name(void) "Checking length"
nbd_negotiate_handle_export_name_request(const char *name) "Client requested export '%s'"
+nbd_negotiate_send_info(int info, const char *name, uint32_t length) "Sending NBD_REP_INFO type %d (%s) with remaining length %" PRIu32
+nbd_negotiate_handle_info_requests(int requests) "Client requested %d items of info"
+nbd_negotiate_handle_info_request(int request, const char *name) "Client requested info %d (%s)"
+nbd_negotiate_handle_info_block_size(uint32_t minimum, uint32_t preferred, uint32_t maximum) "advertising minimum 0x%" PRIx32 ", preferred 0x%" PRIx32 ", maximum 0x%" PRIx32
nbd_negotiate_handle_starttls(void) "Setting up TLS"
nbd_negotiate_handle_starttls_handshake(void) "Starting TLS handshake"
-nbd_negotiate_options_flags(void) "Checking client flags"
-nbd_negotiate_options_newstyle(void) "Client supports fixed newstyle handshake"
-nbd_negotiate_options_no_zeroes(void) "Client supports no zeroes at handshake end"
+nbd_negotiate_options_flags(uint32_t flags) "Received client flags 0x%" PRIx32
nbd_negotiate_options_check_magic(uint64_t magic) "Checking opts magic 0x%" PRIx64
-nbd_negotiate_options_check_option(uint32_t option) "Checking option 0x%" PRIx32
-nbd_opt_abort_reply_failed(const char *error) "Reply to NBD_OPT_ABORT request failed: %s"
+nbd_negotiate_options_check_option(uint32_t option, const char *name) "Checking option 0x%" PRIx32 " (%s)"
nbd_negotiate_begin(void) "Beginning negotiation"
nbd_negotiate_old_style(uint64_t size, unsigned flags) "advertising size %" PRIu64 " and flags %x"
nbd_negotiate_new_style_size_flags(uint64_t size, unsigned flags) "advertising size %" PRIu64 " and flags %x"
@@ -50,7 +55,7 @@ nbd_send_reply(int32_t error, uint64_t handle) "Sending response to client: { .e
nbd_blk_aio_attached(const char *name, void *ctx) "Export %s: Attaching clients to AIO context %p\n"
nbd_blk_aio_detach(const char *name, void *ctx) "Export %s: Detaching clients from AIO context %p\n"
nbd_co_send_reply(uint64_t handle, uint32_t error, int len) "Send reply: handle = %" PRIu64 ", error = %" PRIu32 ", len = %d"
-nbd_co_receive_request_decode_type(uint64_t handle, uint16_t type) "Decoding type: handle = %" PRIu64 ", type = %" PRIu16
+nbd_co_receive_request_decode_type(uint64_t handle, uint16_t type, const char *name) "Decoding type: handle = %" PRIu64 ", type = %" PRIu16 " (%s)"
nbd_co_receive_request_payload_received(uint64_t handle, uint32_t len) "Payload received: handle = %" PRIu64 ", len = %" PRIu32
nbd_co_receive_request_cmd_write(uint32_t len) "Reading %" PRIu32 " byte(s)"
nbd_trip(void) "Reading request"
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-30 13:30:20 +0000