diff options
| -rw-r--r-- | nbd/client.c | 63 | ||||
| -rw-r--r-- | nbd/nbd-internal.h | 34 | ||||
| -rw-r--r-- | nbd/server.c | 84 |
3 files changed, 88 insertions, 93 deletions
diff --git a/nbd/client.c b/nbd/client.c index a58fb02cb4..6b74a628f1 100644 --- a/nbd/client.c +++ b/nbd/client.c @@ -86,9 +86,9 @@ static QTAILQ_HEAD(, NBDExport) exports = QTAILQ_HEAD_INITIALIZER(exports); */ -/* Discard length bytes from channel. Return -errno on failure, or - * the amount of bytes consumed. */ -static ssize_t drop_sync(QIOChannel *ioc, size_t size) +/* Discard length bytes from channel. Return -errno on failure and 0 on + * success*/ +static int drop_sync(QIOChannel *ioc, size_t size) { ssize_t ret = 0; char small[1024]; @@ -96,14 +96,13 @@ static ssize_t drop_sync(QIOChannel *ioc, size_t size) buffer = sizeof(small) >= size ? small : g_malloc(MIN(65536, size)); while (size > 0) { - ssize_t count = read_sync(ioc, buffer, MIN(65536, size)); + ssize_t count = MIN(65536, size); + ret = read_sync(ioc, buffer, MIN(65536, size)); - if (count <= 0) { + if (ret < 0) { goto cleanup; } - assert(count <= size); size -= count; - ret += count; } cleanup: @@ -136,12 +135,12 @@ static int nbd_send_option_request(QIOChannel *ioc, uint32_t opt, stl_be_p(&req.option, opt); stl_be_p(&req.length, len); - if (write_sync(ioc, &req, sizeof(req)) != sizeof(req)) { + if (write_sync(ioc, &req, sizeof(req)) < 0) { error_setg(errp, "Failed to send option request header"); return -1; } - if (len && write_sync(ioc, (char *) data, len) != len) { + if (len && write_sync(ioc, (char *) data, len) < 0) { error_setg(errp, "Failed to send option request data"); return -1; } @@ -170,7 +169,7 @@ static int nbd_receive_option_reply(QIOChannel *ioc, uint32_t opt, nbd_opt_reply *reply, Error **errp) { QEMU_BUILD_BUG_ON(sizeof(*reply) != 20); - if (read_sync(ioc, reply, sizeof(*reply)) != sizeof(*reply)) { + if (read_sync(ioc, reply, sizeof(*reply)) < 0) { error_setg(errp, "failed to read option reply"); nbd_send_opt_abort(ioc); return -1; @@ -219,7 +218,7 @@ static int nbd_handle_reply_err(QIOChannel *ioc, nbd_opt_reply *reply, goto cleanup; } msg = g_malloc(reply->length + 1); - if (read_sync(ioc, msg, reply->length) != reply->length) { + if (read_sync(ioc, msg, reply->length) < 0) { error_setg(errp, "failed to read option error message"); goto cleanup; } @@ -321,7 +320,7 @@ static int nbd_receive_list(QIOChannel *ioc, const char *want, bool *match, nbd_send_opt_abort(ioc); return -1; } - if (read_sync(ioc, &namelen, sizeof(namelen)) != sizeof(namelen)) { + if (read_sync(ioc, &namelen, sizeof(namelen)) < 0) { error_setg(errp, "failed to read option name length"); nbd_send_opt_abort(ioc); return -1; @@ -334,7 +333,7 @@ static int nbd_receive_list(QIOChannel *ioc, const char *want, bool *match, return -1; } if (namelen != strlen(want)) { - if (drop_sync(ioc, len) != len) { + if (drop_sync(ioc, len) < 0) { error_setg(errp, "failed to skip export name with wrong length"); nbd_send_opt_abort(ioc); return -1; @@ -343,14 +342,14 @@ static int nbd_receive_list(QIOChannel *ioc, const char *want, bool *match, } assert(namelen < sizeof(name)); - if (read_sync(ioc, name, namelen) != namelen) { + if (read_sync(ioc, name, namelen) < 0) { error_setg(errp, "failed to read export name"); nbd_send_opt_abort(ioc); return -1; } name[namelen] = '\0'; len -= namelen; - if (drop_sync(ioc, len) != len) { + if (drop_sync(ioc, len) < 0) { error_setg(errp, "failed to read export description"); nbd_send_opt_abort(ioc); return -1; @@ -477,7 +476,7 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint16_t *flags, goto fail; } - if (read_sync(ioc, buf, 8) != 8) { + if (read_sync(ioc, buf, 8) < 0) { error_setg(errp, "Failed to read data"); goto fail; } @@ -503,7 +502,7 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint16_t *flags, goto fail; } - if (read_sync(ioc, &magic, sizeof(magic)) != sizeof(magic)) { + if (read_sync(ioc, &magic, sizeof(magic)) < 0) { error_setg(errp, "Failed to read magic"); goto fail; } @@ -515,8 +514,7 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint16_t *flags, uint16_t globalflags; bool fixedNewStyle = false; - if (read_sync(ioc, &globalflags, sizeof(globalflags)) != - sizeof(globalflags)) { + if (read_sync(ioc, &globalflags, sizeof(globalflags)) < 0) { error_setg(errp, "Failed to read server flags"); goto fail; } @@ -534,8 +532,7 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint16_t *flags, } /* client requested flags */ clientflags = cpu_to_be32(clientflags); - if (write_sync(ioc, &clientflags, sizeof(clientflags)) != - sizeof(clientflags)) { + if (write_sync(ioc, &clientflags, sizeof(clientflags)) < 0) { error_setg(errp, "Failed to send clientflags field"); goto fail; } @@ -573,13 +570,13 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint16_t *flags, } /* Read the response */ - if (read_sync(ioc, &s, sizeof(s)) != sizeof(s)) { + if (read_sync(ioc, &s, sizeof(s)) < 0) { error_setg(errp, "Failed to read export length"); goto fail; } *size = be64_to_cpu(s); - if (read_sync(ioc, flags, sizeof(*flags)) != sizeof(*flags)) { + if (read_sync(ioc, flags, sizeof(*flags)) < 0) { error_setg(errp, "Failed to read export flags"); goto fail; } @@ -596,14 +593,14 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint16_t *flags, goto fail; } - if (read_sync(ioc, &s, sizeof(s)) != sizeof(s)) { + if (read_sync(ioc, &s, sizeof(s)) < 0) { error_setg(errp, "Failed to read export length"); goto fail; } *size = be64_to_cpu(s); TRACE("Size is %" PRIu64, *size); - if (read_sync(ioc, &oldflags, sizeof(oldflags)) != sizeof(oldflags)) { + if (read_sync(ioc, &oldflags, sizeof(oldflags)) < 0) { error_setg(errp, "Failed to read export flags"); goto fail; } @@ -619,7 +616,7 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint16_t *flags, } TRACE("Size is %" PRIu64 ", export flags %" PRIx16, *size, *flags); - if (zeroes && drop_sync(ioc, 124) != 124) { + if (zeroes && drop_sync(ioc, 124) < 0) { error_setg(errp, "Failed to read reserved block"); goto fail; } @@ -744,7 +741,6 @@ int nbd_disconnect(int fd) ssize_t nbd_send_request(QIOChannel *ioc, NBDRequest *request) { uint8_t buf[NBD_REQUEST_SIZE]; - ssize_t ret; TRACE("Sending request to server: " "{ .from = %" PRIu64", .len = %" PRIu32 ", .handle = %" PRIu64 @@ -759,16 +755,7 @@ ssize_t nbd_send_request(QIOChannel *ioc, NBDRequest *request) stq_be_p(buf + 16, request->from); stl_be_p(buf + 24, request->len); - ret = write_sync(ioc, buf, sizeof(buf)); - if (ret < 0) { - return ret; - } - - if (ret != sizeof(buf)) { - LOG("writing to socket failed"); - return -EINVAL; - } - return 0; + return write_sync(ioc, buf, sizeof(buf)); } ssize_t nbd_receive_reply(QIOChannel *ioc, NBDReply *reply) @@ -777,7 +764,7 @@ ssize_t nbd_receive_reply(QIOChannel *ioc, NBDReply *reply) uint32_t magic; ssize_t ret; - ret = read_sync(ioc, buf, sizeof(buf)); + ret = read_sync_eof(ioc, buf, sizeof(buf)); if (ret <= 0) { return ret; } diff --git a/nbd/nbd-internal.h b/nbd/nbd-internal.h index f43d990a05..e6bbc7c4b4 100644 --- a/nbd/nbd-internal.h +++ b/nbd/nbd-internal.h @@ -94,7 +94,13 @@ #define NBD_ENOSPC 28 #define NBD_ESHUTDOWN 108 -static inline ssize_t read_sync(QIOChannel *ioc, void *buffer, size_t size) +/* read_sync_eof + * Tries to read @size bytes from @ioc. Returns number of bytes actually read. + * May return a value >= 0 and < size only on EOF, i.e. when iteratively called + * qio_channel_readv() returns 0. So, there are no needs to call read_sync_eof + * iteratively. + */ +static inline ssize_t read_sync_eof(QIOChannel *ioc, void *buffer, size_t size) { struct iovec iov = { .iov_base = buffer, .iov_len = size }; /* Sockets are kept in blocking mode in the negotiation phase. After @@ -105,12 +111,32 @@ static inline ssize_t read_sync(QIOChannel *ioc, void *buffer, size_t size) return nbd_wr_syncv(ioc, &iov, 1, size, true); } -static inline ssize_t write_sync(QIOChannel *ioc, const void *buffer, - size_t size) +/* read_sync + * Reads @size bytes from @ioc. Returns 0 on success. + */ +static inline int read_sync(QIOChannel *ioc, void *buffer, size_t size) +{ + ssize_t ret = read_sync_eof(ioc, buffer, size); + + if (ret >= 0 && ret != size) { + ret = -EINVAL; + } + + return ret < 0 ? ret : 0; +} + +/* write_sync + * Writes @size bytes to @ioc. Returns 0 on success. + */ +static inline int write_sync(QIOChannel *ioc, const void *buffer, size_t size) { struct iovec iov = { .iov_base = (void *) buffer, .iov_len = size }; - return nbd_wr_syncv(ioc, &iov, 1, size, false); + ssize_t ret = nbd_wr_syncv(ioc, &iov, 1, size, false); + + assert(ret < 0 || ret == size); + + return ret < 0 ? ret : 0; } struct NBDTLSHandshakeData { diff --git a/nbd/server.c b/nbd/server.c index 924a1fe2db..1e1096c762 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -112,7 +112,7 @@ static gboolean nbd_negotiate_continue(QIOChannel *ioc, return TRUE; } -static ssize_t nbd_negotiate_read(QIOChannel *ioc, void *buffer, size_t size) +static int nbd_negotiate_read(QIOChannel *ioc, void *buffer, size_t size) { ssize_t ret; guint watch; @@ -130,8 +130,7 @@ static ssize_t nbd_negotiate_read(QIOChannel *ioc, void *buffer, size_t size) } -static ssize_t nbd_negotiate_write(QIOChannel *ioc, const void *buffer, - size_t size) +static int nbd_negotiate_write(QIOChannel *ioc, const void *buffer, size_t size) { ssize_t ret; guint watch; @@ -148,24 +147,24 @@ static ssize_t nbd_negotiate_write(QIOChannel *ioc, const void *buffer, return ret; } -static ssize_t nbd_negotiate_drop_sync(QIOChannel *ioc, size_t size) +static int nbd_negotiate_drop_sync(QIOChannel *ioc, size_t size) { - ssize_t ret, dropped = size; + ssize_t ret; uint8_t *buffer = g_malloc(MIN(65536, size)); while (size > 0) { - ret = nbd_negotiate_read(ioc, buffer, MIN(65536, size)); + size_t count = MIN(65536, size); + ret = nbd_negotiate_read(ioc, buffer, count); if (ret < 0) { g_free(buffer); return ret; } - assert(ret <= size); - size -= ret; + size -= count; } g_free(buffer); - return dropped; + return 0; } /* Basic flow for negotiation @@ -206,22 +205,22 @@ static int nbd_negotiate_send_rep_len(QIOChannel *ioc, uint32_t type, type, opt, len); magic = cpu_to_be64(NBD_REP_MAGIC); - if (nbd_negotiate_write(ioc, &magic, sizeof(magic)) != sizeof(magic)) { + if (nbd_negotiate_write(ioc, &magic, sizeof(magic)) < 0) { LOG("write failed (rep magic)"); return -EINVAL; } opt = cpu_to_be32(opt); - if (nbd_negotiate_write(ioc, &opt, sizeof(opt)) != sizeof(opt)) { + if (nbd_negotiate_write(ioc, &opt, sizeof(opt)) < 0) { LOG("write failed (rep opt)"); return -EINVAL; } type = cpu_to_be32(type); - if (nbd_negotiate_write(ioc, &type, sizeof(type)) != sizeof(type)) { + if (nbd_negotiate_write(ioc, &type, sizeof(type)) < 0) { LOG("write failed (rep type)"); return -EINVAL; } len = cpu_to_be32(len); - if (nbd_negotiate_write(ioc, &len, sizeof(len)) != sizeof(len)) { + if (nbd_negotiate_write(ioc, &len, sizeof(len)) < 0) { LOG("write failed (rep data length)"); return -EINVAL; } @@ -256,7 +255,7 @@ nbd_negotiate_send_rep_err(QIOChannel *ioc, uint32_t type, if (ret < 0) { goto out; } - if (nbd_negotiate_write(ioc, msg, len) != len) { + if (nbd_negotiate_write(ioc, msg, len) < 0) { LOG("write failed (error message)"); ret = -EIO; } else { @@ -287,15 +286,15 @@ static int nbd_negotiate_send_rep_list(QIOChannel *ioc, NBDExport *exp) } len = cpu_to_be32(name_len); - if (nbd_negotiate_write(ioc, &len, sizeof(len)) != sizeof(len)) { + if (nbd_negotiate_write(ioc, &len, sizeof(len)) < 0) { LOG("write failed (name length)"); return -EINVAL; } - if (nbd_negotiate_write(ioc, name, name_len) != name_len) { + if (nbd_negotiate_write(ioc, name, name_len) < 0) { LOG("write failed (name buffer)"); return -EINVAL; } - if (nbd_negotiate_write(ioc, desc, desc_len) != desc_len) { + if (nbd_negotiate_write(ioc, desc, desc_len) < 0) { LOG("write failed (description buffer)"); return -EINVAL; } @@ -309,7 +308,7 @@ static int nbd_negotiate_handle_list(NBDClient *client, uint32_t length) NBDExport *exp; if (length) { - if (nbd_negotiate_drop_sync(client->ioc, length) != length) { + if (nbd_negotiate_drop_sync(client->ioc, length) < 0) { return -EIO; } return nbd_negotiate_send_rep_err(client->ioc, @@ -340,7 +339,7 @@ static int nbd_negotiate_handle_export_name(NBDClient *client, uint32_t length) LOG("Bad length received"); goto fail; } - if (nbd_negotiate_read(client->ioc, name, length) != length) { + if (nbd_negotiate_read(client->ioc, name, length) < 0) { LOG("read failed"); goto fail; } @@ -373,7 +372,7 @@ static QIOChannel *nbd_negotiate_handle_starttls(NBDClient *client, TRACE("Setting up TLS"); ioc = client->ioc; if (length) { - if (nbd_negotiate_drop_sync(ioc, length) != length) { + if (nbd_negotiate_drop_sync(ioc, length) < 0) { return NULL; } nbd_negotiate_send_rep_err(ioc, NBD_REP_ERR_INVALID, NBD_OPT_STARTTLS, @@ -437,8 +436,7 @@ static int nbd_negotiate_options(NBDClient *client) ... Rest of request */ - if (nbd_negotiate_read(client->ioc, &flags, sizeof(flags)) != - sizeof(flags)) { + if (nbd_negotiate_read(client->ioc, &flags, sizeof(flags)) < 0) { LOG("read failed"); return -EIO; } @@ -464,8 +462,7 @@ static int nbd_negotiate_options(NBDClient *client) uint32_t clientflags, length; uint64_t magic; - if (nbd_negotiate_read(client->ioc, &magic, sizeof(magic)) != - sizeof(magic)) { + if (nbd_negotiate_read(client->ioc, &magic, sizeof(magic)) < 0) { LOG("read failed"); return -EINVAL; } @@ -476,14 +473,14 @@ static int nbd_negotiate_options(NBDClient *client) } if (nbd_negotiate_read(client->ioc, &clientflags, - sizeof(clientflags)) != sizeof(clientflags)) { + sizeof(clientflags)) < 0) + { LOG("read failed"); return -EINVAL; } clientflags = be32_to_cpu(clientflags); - if (nbd_negotiate_read(client->ioc, &length, sizeof(length)) != - sizeof(length)) { + if (nbd_negotiate_read(client->ioc, &length, sizeof(length)) < 0) { LOG("read failed"); return -EINVAL; } @@ -513,7 +510,7 @@ static int nbd_negotiate_options(NBDClient *client) return -EINVAL; default: - if (nbd_negotiate_drop_sync(client->ioc, length) != length) { + if (nbd_negotiate_drop_sync(client->ioc, length) < 0) { return -EIO; } ret = nbd_negotiate_send_rep_err(client->ioc, @@ -551,7 +548,7 @@ static int nbd_negotiate_options(NBDClient *client) return nbd_negotiate_handle_export_name(client, length); case NBD_OPT_STARTTLS: - if (nbd_negotiate_drop_sync(client->ioc, length) != length) { + if (nbd_negotiate_drop_sync(client->ioc, length) < 0) { return -EIO; } if (client->tlscreds) { @@ -570,7 +567,7 @@ static int nbd_negotiate_options(NBDClient *client) } break; default: - if (nbd_negotiate_drop_sync(client->ioc, length) != length) { + if (nbd_negotiate_drop_sync(client->ioc, length) < 0) { return -EIO; } ret = nbd_negotiate_send_rep_err(client->ioc, @@ -659,12 +656,12 @@ static coroutine_fn int nbd_negotiate(NBDClientNewData *data) TRACE("TLS cannot be enabled with oldstyle protocol"); goto fail; } - if (nbd_negotiate_write(client->ioc, buf, sizeof(buf)) != sizeof(buf)) { + if (nbd_negotiate_write(client->ioc, buf, sizeof(buf)) < 0) { LOG("write failed"); goto fail; } } else { - if (nbd_negotiate_write(client->ioc, buf, 18) != 18) { + if (nbd_negotiate_write(client->ioc, buf, 18) < 0) { LOG("write failed"); goto fail; } @@ -679,7 +676,7 @@ static coroutine_fn int nbd_negotiate(NBDClientNewData *data) 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; - if (nbd_negotiate_write(client->ioc, buf + 18, len) != len) { + if (nbd_negotiate_write(client->ioc, buf + 18, len) < 0) { LOG("write failed"); goto fail; } @@ -702,11 +699,6 @@ static ssize_t nbd_receive_request(QIOChannel *ioc, NBDRequest *request) return ret; } - if (ret != sizeof(buf)) { - LOG("read failed"); - return -EINVAL; - } - /* Request [ 0 .. 3] magic (NBD_REQUEST_MAGIC) [ 4 .. 5] flags (NBD_CMD_FLAG_FUA, ...) @@ -737,7 +729,6 @@ static ssize_t nbd_receive_request(QIOChannel *ioc, NBDRequest *request) static ssize_t nbd_send_reply(QIOChannel *ioc, NBDReply *reply) { uint8_t buf[NBD_REPLY_SIZE]; - ssize_t ret; reply->error = system_errno_to_nbd_errno(reply->error); @@ -754,16 +745,7 @@ static ssize_t nbd_send_reply(QIOChannel *ioc, NBDReply *reply) stl_be_p(buf + 4, reply->error); stq_be_p(buf + 8, reply->handle); - ret = write_sync(ioc, buf, sizeof(buf)); - if (ret < 0) { - return ret; - } - - if (ret != sizeof(buf)) { - LOG("writing to socket failed"); - return -EINVAL; - } - return 0; + return write_sync(ioc, buf, sizeof(buf)); } #define MAX_NBD_REQUESTS 16 @@ -1067,7 +1049,7 @@ static ssize_t nbd_co_send_reply(NBDRequestData *req, NBDReply *reply, rc = nbd_send_reply(client->ioc, reply); if (rc >= 0) { ret = write_sync(client->ioc, req->data, len); - if (ret != len) { + if (ret < 0) { rc = -EIO; } } @@ -1141,7 +1123,7 @@ static ssize_t nbd_co_receive_request(NBDRequestData *req, if (request->type == NBD_CMD_WRITE) { TRACE("Reading %" PRIu32 " byte(s)", request->len); - if (read_sync(client->ioc, req->data, request->len) != request->len) { + if (read_sync(client->ioc, req->data, request->len) < 0) { LOG("reading from socket failed"); rc = -EIO; goto out; |