diff options
Diffstat (limited to 'nbd')
| -rw-r--r-- | nbd/client.c | 104 | ||||
| -rw-r--r-- | nbd/trace-events | 3 |
2 files changed, 71 insertions, 36 deletions
diff --git a/nbd/client.c b/nbd/client.c index cecb0f0437..a2f253062a 100644 --- a/nbd/client.c +++ b/nbd/client.c @@ -1346,22 +1346,29 @@ int nbd_disconnect(int fd) int nbd_send_request(QIOChannel *ioc, NBDRequest *request) { - uint8_t buf[NBD_REQUEST_SIZE]; + uint8_t buf[NBD_EXTENDED_REQUEST_SIZE]; + size_t len; - assert(request->mode <= NBD_MODE_STRUCTURED); /* TODO handle extended */ - assert(request->len <= UINT32_MAX); trace_nbd_send_request(request->from, request->len, request->cookie, request->flags, request->type, nbd_cmd_lookup(request->type)); - stl_be_p(buf, NBD_REQUEST_MAGIC); stw_be_p(buf + 4, request->flags); stw_be_p(buf + 6, request->type); stq_be_p(buf + 8, request->cookie); stq_be_p(buf + 16, request->from); - stl_be_p(buf + 24, request->len); + if (request->mode >= NBD_MODE_EXTENDED) { + stl_be_p(buf, NBD_EXTENDED_REQUEST_MAGIC); + stq_be_p(buf + 24, request->len); + len = NBD_EXTENDED_REQUEST_SIZE; + } else { + assert(request->len <= UINT32_MAX); + stl_be_p(buf, NBD_REQUEST_MAGIC); + stl_be_p(buf + 24, request->len); + len = NBD_REQUEST_SIZE; + } - return nbd_write(ioc, buf, sizeof(buf), NULL); + return nbd_write(ioc, buf, len, NULL); } /* nbd_receive_simple_reply @@ -1388,30 +1395,36 @@ static int nbd_receive_simple_reply(QIOChannel *ioc, NBDSimpleReply *reply, return 0; } -/* nbd_receive_structured_reply_chunk +/* nbd_receive_reply_chunk_header * Read structured reply chunk except magic field (which should be already - * read). + * read). Normalize into the compact form. * Payload is not read. */ -static int nbd_receive_structured_reply_chunk(QIOChannel *ioc, - NBDStructuredReplyChunk *chunk, - Error **errp) +static int nbd_receive_reply_chunk_header(QIOChannel *ioc, NBDReply *chunk, + Error **errp) { int ret; + size_t len; + uint64_t payload_len; - assert(chunk->magic == NBD_STRUCTURED_REPLY_MAGIC); + if (chunk->magic == NBD_STRUCTURED_REPLY_MAGIC) { + len = sizeof(chunk->structured); + } else { + assert(chunk->magic == NBD_EXTENDED_REPLY_MAGIC); + len = sizeof(chunk->extended); + } ret = nbd_read(ioc, (uint8_t *)chunk + sizeof(chunk->magic), - sizeof(*chunk) - sizeof(chunk->magic), "structured chunk", + len - sizeof(chunk->magic), "structured chunk", errp); if (ret < 0) { return ret; } - chunk->flags = be16_to_cpu(chunk->flags); - chunk->type = be16_to_cpu(chunk->type); - chunk->cookie = be64_to_cpu(chunk->cookie); - chunk->length = be32_to_cpu(chunk->length); + /* flags, type, and cookie occupy same space between forms */ + chunk->structured.flags = be16_to_cpu(chunk->structured.flags); + chunk->structured.type = be16_to_cpu(chunk->structured.type); + chunk->structured.cookie = be64_to_cpu(chunk->structured.cookie); /* * Because we use BLOCK_STATUS with REQ_ONE, and cap READ requests @@ -1419,11 +1432,20 @@ static int nbd_receive_structured_reply_chunk(QIOChannel *ioc, * this. Even if we stopped using REQ_ONE, sane servers will cap * the number of extents they return for block status. */ - if (chunk->length > NBD_MAX_BUFFER_SIZE + sizeof(NBDStructuredReadData)) { + if (chunk->magic == NBD_STRUCTURED_REPLY_MAGIC) { + payload_len = be32_to_cpu(chunk->structured.length); + } else { + /* For now, we are ignoring the extended header offset. */ + payload_len = be64_to_cpu(chunk->extended.length); + chunk->magic = NBD_STRUCTURED_REPLY_MAGIC; + } + if (payload_len > NBD_MAX_BUFFER_SIZE + sizeof(NBDStructuredReadData)) { error_setg(errp, "server chunk %" PRIu32 " (%s) payload is too long", - chunk->type, nbd_rep_lookup(chunk->type)); + chunk->structured.type, + nbd_rep_lookup(chunk->structured.type)); return -EINVAL; } + chunk->structured.length = payload_len; return 0; } @@ -1470,19 +1492,21 @@ nbd_read_eof(BlockDriverState *bs, QIOChannel *ioc, void *buffer, size_t size, /* nbd_receive_reply * - * Decreases bs->in_flight while waiting for a new reply. This yield is where - * we wait indefinitely and the coroutine must be able to be safely reentered - * for nbd_client_attach_aio_context(). + * Wait for a new reply. If this yields, the coroutine must be able to be + * safely reentered for nbd_client_attach_aio_context(). @mode determines + * which reply magic we are expecting, although this normalizes the result + * so that the caller only has to work with compact headers. * * Returns 1 on success - * 0 on eof, when no data was read (errp is not set) - * negative errno on failure (errp is set) + * 0 on eof, when no data was read + * negative errno on failure */ int coroutine_fn nbd_receive_reply(BlockDriverState *bs, QIOChannel *ioc, - NBDReply *reply, Error **errp) + NBDReply *reply, NBDMode mode, Error **errp) { int ret; const char *type; + uint32_t expected; ret = nbd_read_eof(bs, ioc, &reply->magic, sizeof(reply->magic), errp); if (ret <= 0) { @@ -1491,34 +1515,44 @@ int coroutine_fn nbd_receive_reply(BlockDriverState *bs, QIOChannel *ioc, reply->magic = be32_to_cpu(reply->magic); + /* Diagnose but accept wrong-width header */ switch (reply->magic) { case NBD_SIMPLE_REPLY_MAGIC: + if (mode >= NBD_MODE_EXTENDED) { + trace_nbd_receive_wrong_header(reply->magic, + nbd_mode_lookup(mode)); + } ret = nbd_receive_simple_reply(ioc, &reply->simple, errp); if (ret < 0) { - break; + return ret; } trace_nbd_receive_simple_reply(reply->simple.error, nbd_err_lookup(reply->simple.error), reply->cookie); break; case NBD_STRUCTURED_REPLY_MAGIC: - ret = nbd_receive_structured_reply_chunk(ioc, &reply->structured, errp); + case NBD_EXTENDED_REPLY_MAGIC: + expected = mode >= NBD_MODE_EXTENDED ? NBD_EXTENDED_REPLY_MAGIC + : NBD_STRUCTURED_REPLY_MAGIC; + if (reply->magic != expected) { + trace_nbd_receive_wrong_header(reply->magic, + nbd_mode_lookup(mode)); + } + ret = nbd_receive_reply_chunk_header(ioc, reply, errp); if (ret < 0) { - break; + return ret; } type = nbd_reply_type_lookup(reply->structured.type); - trace_nbd_receive_structured_reply_chunk(reply->structured.flags, - reply->structured.type, type, - reply->structured.cookie, - reply->structured.length); + trace_nbd_receive_reply_chunk_header(reply->structured.flags, + reply->structured.type, type, + reply->structured.cookie, + reply->structured.length); break; default: + trace_nbd_receive_wrong_header(reply->magic, nbd_mode_lookup(mode)); error_setg(errp, "invalid magic (got 0x%" PRIx32 ")", reply->magic); return -EINVAL; } - if (ret < 0) { - return ret; - } return 1; } diff --git a/nbd/trace-events b/nbd/trace-events index c1a3227613..cb5d719ed6 100644 --- a/nbd/trace-events +++ b/nbd/trace-events @@ -33,7 +33,8 @@ nbd_client_clear_queue(void) "Clearing NBD queue" nbd_client_clear_socket(void) "Clearing NBD socket" nbd_send_request(uint64_t from, uint64_t len, uint64_t cookie, uint16_t flags, uint16_t type, const char *name) "Sending request to server: { .from = %" PRIu64", .len = %" PRIu64 ", .cookie = %" PRIu64 ", .flags = 0x%" PRIx16 ", .type = %" PRIu16 " (%s) }" nbd_receive_simple_reply(int32_t error, const char *errname, uint64_t cookie) "Got simple reply: { .error = %" PRId32 " (%s), cookie = %" PRIu64" }" -nbd_receive_structured_reply_chunk(uint16_t flags, uint16_t type, const char *name, uint64_t cookie, uint32_t length) "Got structured reply chunk: { flags = 0x%" PRIx16 ", type = %d (%s), cookie = %" PRIu64 ", length = %" PRIu32 " }" +nbd_receive_reply_chunk_header(uint16_t flags, uint16_t type, const char *name, uint64_t cookie, uint32_t length) "Got reply chunk header: { flags = 0x%" PRIx16 ", type = %" PRIu16 " (%s), cookie = %" PRIu64 ", length = %" PRIu32 " }" +nbd_receive_wrong_header(uint32_t magic, const char *mode) "Server sent unexpected magic 0x%" PRIx32 " for negotiated mode %s" # common.c nbd_unknown_error(int err) "Squashing unexpected error %d to EINVAL" |