diff options
Diffstat (limited to 'nbd.c')
| -rw-r--r-- | nbd.c | 835 |
1 files changed, 418 insertions, 417 deletions
@@ -49,7 +49,7 @@ /* This is all part of the "official" NBD API */ -#define NBD_REPLY_SIZE (4 + 4 + 8) +#define NBD_REPLY_SIZE (4 + 4 + 8) #define NBD_REQUEST_MAGIC 0x25609513 #define NBD_REPLY_MAGIC 0x67446698 @@ -59,11 +59,11 @@ #define NBD_DO_IT _IO(0xab, 3) #define NBD_CLEAR_SOCK _IO(0xab, 4) #define NBD_CLEAR_QUE _IO(0xab, 5) -#define NBD_PRINT_DEBUG _IO(0xab, 6) -#define NBD_SET_SIZE_BLOCKS _IO(0xab, 7) +#define NBD_PRINT_DEBUG _IO(0xab, 6) +#define NBD_SET_SIZE_BLOCKS _IO(0xab, 7) #define NBD_DISCONNECT _IO(0xab, 8) -#define NBD_OPT_EXPORT_NAME (1 << 0) +#define NBD_OPT_EXPORT_NAME (1 << 0) /* That's all folks */ @@ -273,241 +273,241 @@ int unix_socket_outgoing(const char *path) int nbd_negotiate(int csock, off_t size) { - char buf[8 + 8 + 8 + 128]; - - /* Negotiate - [ 0 .. 7] passwd ("NBDMAGIC") - [ 8 .. 15] magic (0x00420281861253) - [16 .. 23] size - [24 .. 151] reserved (0) - */ - - TRACE("Beginning negotiation."); - memcpy(buf, "NBDMAGIC", 8); - cpu_to_be64w((uint64_t*)(buf + 8), 0x00420281861253LL); - cpu_to_be64w((uint64_t*)(buf + 16), size); - memset(buf + 24, 0, 128); - - if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { - LOG("write failed"); - errno = EINVAL; - return -1; - } - - TRACE("Negotation succeeded."); - - return 0; + char buf[8 + 8 + 8 + 128]; + + /* Negotiate + [ 0 .. 7] passwd ("NBDMAGIC") + [ 8 .. 15] magic (0x00420281861253) + [16 .. 23] size + [24 .. 151] reserved (0) + */ + + TRACE("Beginning negotiation."); + memcpy(buf, "NBDMAGIC", 8); + cpu_to_be64w((uint64_t*)(buf + 8), 0x00420281861253LL); + cpu_to_be64w((uint64_t*)(buf + 16), size); + memset(buf + 24, 0, 128); + + if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { + LOG("write failed"); + errno = EINVAL; + return -1; + } + + TRACE("Negotation succeeded."); + + return 0; } int nbd_receive_negotiate(int csock, const char *name, uint32_t *flags, off_t *size, size_t *blocksize) { - char buf[256]; - uint64_t magic, s; - uint16_t tmp; - - TRACE("Receiving negotation."); - - if (read_sync(csock, buf, 8) != 8) { - LOG("read failed"); - errno = EINVAL; - return -1; - } - - buf[8] = '\0'; - if (strlen(buf) == 0) { - LOG("server connection closed"); - errno = EINVAL; - return -1; - } - - TRACE("Magic is %c%c%c%c%c%c%c%c", - qemu_isprint(buf[0]) ? buf[0] : '.', - qemu_isprint(buf[1]) ? buf[1] : '.', - qemu_isprint(buf[2]) ? buf[2] : '.', - qemu_isprint(buf[3]) ? buf[3] : '.', - qemu_isprint(buf[4]) ? buf[4] : '.', - qemu_isprint(buf[5]) ? buf[5] : '.', - qemu_isprint(buf[6]) ? buf[6] : '.', - qemu_isprint(buf[7]) ? buf[7] : '.'); - - if (memcmp(buf, "NBDMAGIC", 8) != 0) { - LOG("Invalid magic received"); - errno = EINVAL; - return -1; - } - - if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { - LOG("read failed"); - errno = EINVAL; - return -1; - } - magic = be64_to_cpu(magic); - TRACE("Magic is 0x%" PRIx64, magic); - - if (name) { - uint32_t reserved = 0; - uint32_t opt; - uint32_t namesize; - - TRACE("Checking magic (opts_magic)"); - if (magic != 0x49484156454F5054LL) { - LOG("Bad magic received"); - errno = EINVAL; - return -1; - } - if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { - LOG("flags read failed"); - errno = EINVAL; - return -1; - } - *flags = be16_to_cpu(tmp) << 16; - /* reserved for future use */ - if (write_sync(csock, &reserved, sizeof(reserved)) != - sizeof(reserved)) { - LOG("write failed (reserved)"); - errno = EINVAL; - return -1; - } - /* write the export name */ - magic = cpu_to_be64(magic); - if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { - LOG("write failed (magic)"); - errno = EINVAL; - return -1; - } - opt = cpu_to_be32(NBD_OPT_EXPORT_NAME); - if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) { - LOG("write failed (opt)"); - errno = EINVAL; - return -1; - } - namesize = cpu_to_be32(strlen(name)); - if (write_sync(csock, &namesize, sizeof(namesize)) != - sizeof(namesize)) { - LOG("write failed (namesize)"); - errno = EINVAL; - return -1; - } - if (write_sync(csock, (char*)name, strlen(name)) != strlen(name)) { - LOG("write failed (name)"); - errno = EINVAL; - return -1; - } - } else { - TRACE("Checking magic (cli_magic)"); - - if (magic != 0x00420281861253LL) { - LOG("Bad magic received"); - errno = EINVAL; - return -1; - } - } - - if (read_sync(csock, &s, sizeof(s)) != sizeof(s)) { - LOG("read failed"); - errno = EINVAL; - return -1; - } - *size = be64_to_cpu(s); - *blocksize = 1024; - TRACE("Size is %" PRIu64, *size); - - if (!name) { - if (read_sync(csock, flags, sizeof(*flags)) != sizeof(*flags)) { - LOG("read failed (flags)"); - errno = EINVAL; - return -1; - } - *flags = be32_to_cpup(flags); - } else { - if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { - LOG("read failed (tmp)"); - errno = EINVAL; - return -1; - } - *flags |= be32_to_cpu(tmp); - } - if (read_sync(csock, &buf, 124) != 124) { - LOG("read failed (buf)"); - errno = EINVAL; - return -1; - } + char buf[256]; + uint64_t magic, s; + uint16_t tmp; + + TRACE("Receiving negotation."); + + if (read_sync(csock, buf, 8) != 8) { + LOG("read failed"); + errno = EINVAL; + return -1; + } + + buf[8] = '\0'; + if (strlen(buf) == 0) { + LOG("server connection closed"); + errno = EINVAL; + return -1; + } + + TRACE("Magic is %c%c%c%c%c%c%c%c", + qemu_isprint(buf[0]) ? buf[0] : '.', + qemu_isprint(buf[1]) ? buf[1] : '.', + qemu_isprint(buf[2]) ? buf[2] : '.', + qemu_isprint(buf[3]) ? buf[3] : '.', + qemu_isprint(buf[4]) ? buf[4] : '.', + qemu_isprint(buf[5]) ? buf[5] : '.', + qemu_isprint(buf[6]) ? buf[6] : '.', + qemu_isprint(buf[7]) ? buf[7] : '.'); + + if (memcmp(buf, "NBDMAGIC", 8) != 0) { + LOG("Invalid magic received"); + errno = EINVAL; + return -1; + } + + if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { + LOG("read failed"); + errno = EINVAL; + return -1; + } + magic = be64_to_cpu(magic); + TRACE("Magic is 0x%" PRIx64, magic); + + if (name) { + uint32_t reserved = 0; + uint32_t opt; + uint32_t namesize; + + TRACE("Checking magic (opts_magic)"); + if (magic != 0x49484156454F5054LL) { + LOG("Bad magic received"); + errno = EINVAL; + return -1; + } + if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { + LOG("flags read failed"); + errno = EINVAL; + return -1; + } + *flags = be16_to_cpu(tmp) << 16; + /* reserved for future use */ + if (write_sync(csock, &reserved, sizeof(reserved)) != + sizeof(reserved)) { + LOG("write failed (reserved)"); + errno = EINVAL; + return -1; + } + /* write the export name */ + magic = cpu_to_be64(magic); + if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { + LOG("write failed (magic)"); + errno = EINVAL; + return -1; + } + opt = cpu_to_be32(NBD_OPT_EXPORT_NAME); + if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) { + LOG("write failed (opt)"); + errno = EINVAL; + return -1; + } + namesize = cpu_to_be32(strlen(name)); + if (write_sync(csock, &namesize, sizeof(namesize)) != + sizeof(namesize)) { + LOG("write failed (namesize)"); + errno = EINVAL; + return -1; + } + if (write_sync(csock, (char*)name, strlen(name)) != strlen(name)) { + LOG("write failed (name)"); + errno = EINVAL; + return -1; + } + } else { + TRACE("Checking magic (cli_magic)"); + + if (magic != 0x00420281861253LL) { + LOG("Bad magic received"); + errno = EINVAL; + return -1; + } + } + + if (read_sync(csock, &s, sizeof(s)) != sizeof(s)) { + LOG("read failed"); + errno = EINVAL; + return -1; + } + *size = be64_to_cpu(s); + *blocksize = 1024; + TRACE("Size is %" PRIu64, *size); + + if (!name) { + if (read_sync(csock, flags, sizeof(*flags)) != sizeof(*flags)) { + LOG("read failed (flags)"); + errno = EINVAL; + return -1; + } + *flags = be32_to_cpup(flags); + } else { + if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { + LOG("read failed (tmp)"); + errno = EINVAL; + return -1; + } + *flags |= be32_to_cpu(tmp); + } + if (read_sync(csock, &buf, 124) != 124) { + LOG("read failed (buf)"); + errno = EINVAL; + return -1; + } return 0; } #ifndef _WIN32 int nbd_init(int fd, int csock, off_t size, size_t blocksize) { - TRACE("Setting block size to %lu", (unsigned long)blocksize); + TRACE("Setting block size to %lu", (unsigned long)blocksize); - if (ioctl(fd, NBD_SET_BLKSIZE, blocksize) == -1) { - int serrno = errno; - LOG("Failed setting NBD block size"); - errno = serrno; - return -1; - } + if (ioctl(fd, NBD_SET_BLKSIZE, blocksize) == -1) { + int serrno = errno; + LOG("Failed setting NBD block size"); + errno = serrno; + return -1; + } TRACE("Setting size to %zd block(s)", (size_t)(size / blocksize)); - if (ioctl(fd, NBD_SET_SIZE_BLOCKS, size / blocksize) == -1) { - int serrno = errno; - LOG("Failed setting size (in blocks)"); - errno = serrno; - return -1; - } + if (ioctl(fd, NBD_SET_SIZE_BLOCKS, size / blocksize) == -1) { + int serrno = errno; + LOG("Failed setting size (in blocks)"); + errno = serrno; + return -1; + } - TRACE("Clearing NBD socket"); + TRACE("Clearing NBD socket"); - if (ioctl(fd, NBD_CLEAR_SOCK) == -1) { - int serrno = errno; - LOG("Failed clearing NBD socket"); - errno = serrno; - return -1; - } + if (ioctl(fd, NBD_CLEAR_SOCK) == -1) { + int serrno = errno; + LOG("Failed clearing NBD socket"); + errno = serrno; + return -1; + } - TRACE("Setting NBD socket"); + TRACE("Setting NBD socket"); - if (ioctl(fd, NBD_SET_SOCK, csock) == -1) { - int serrno = errno; - LOG("Failed to set NBD socket"); - errno = serrno; - return -1; - } + if (ioctl(fd, NBD_SET_SOCK, csock) == -1) { + int serrno = errno; + LOG("Failed to set NBD socket"); + errno = serrno; + return -1; + } - TRACE("Negotiation ended"); + TRACE("Negotiation ended"); - return 0; + return 0; } int nbd_disconnect(int fd) { - ioctl(fd, NBD_CLEAR_QUE); - ioctl(fd, NBD_DISCONNECT); - ioctl(fd, NBD_CLEAR_SOCK); - return 0; + ioctl(fd, NBD_CLEAR_QUE); + ioctl(fd, NBD_DISCONNECT); + ioctl(fd, NBD_CLEAR_SOCK); + return 0; } int nbd_client(int fd) { - int ret; - int serrno; + int ret; + int serrno; - TRACE("Doing NBD loop"); + TRACE("Doing NBD loop"); - ret = ioctl(fd, NBD_DO_IT); - serrno = errno; + ret = ioctl(fd, NBD_DO_IT); + serrno = errno; - TRACE("NBD loop returned %d: %s", ret, strerror(serrno)); + TRACE("NBD loop returned %d: %s", ret, strerror(serrno)); - TRACE("Clearing NBD queue"); - ioctl(fd, NBD_CLEAR_QUE); + TRACE("Clearing NBD queue"); + ioctl(fd, NBD_CLEAR_QUE); - TRACE("Clearing NBD socket"); - ioctl(fd, NBD_CLEAR_SOCK); + TRACE("Clearing NBD socket"); + ioctl(fd, NBD_CLEAR_SOCK); - errno = serrno; - return ret; + errno = serrno; + return ret; } #else int nbd_init(int fd, int csock, off_t size, size_t blocksize) @@ -531,235 +531,236 @@ int nbd_client(int fd) int nbd_send_request(int csock, struct nbd_request *request) { - uint8_t buf[4 + 4 + 8 + 8 + 4]; - - cpu_to_be32w((uint32_t*)buf, NBD_REQUEST_MAGIC); - cpu_to_be32w((uint32_t*)(buf + 4), request->type); - cpu_to_be64w((uint64_t*)(buf + 8), request->handle); - cpu_to_be64w((uint64_t*)(buf + 16), request->from); - cpu_to_be32w((uint32_t*)(buf + 24), request->len); - - TRACE("Sending request to client"); - - if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { - LOG("writing to socket failed"); - errno = EINVAL; - return -1; - } - return 0; -} + uint8_t buf[4 + 4 + 8 + 8 + 4]; + + cpu_to_be32w((uint32_t*)buf, NBD_REQUEST_MAGIC); + cpu_to_be32w((uint32_t*)(buf + 4), request->type); + cpu_to_be64w((uint64_t*)(buf + 8), request->handle); + cpu_to_be64w((uint64_t*)(buf + 16), request->from); + cpu_to_be32w((uint32_t*)(buf + 24), request->len); + TRACE("Sending request to client: " + "{ .from = %" PRIu64", .len = %u, .handle = %" PRIu64", .type=%i}", + request->from, request->len, request->handle, request->type); + + if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { + LOG("writing to socket failed"); + errno = EINVAL; + return -1; + } + return 0; +} static int nbd_receive_request(int csock, struct nbd_request *request) { - uint8_t buf[4 + 4 + 8 + 8 + 4]; - uint32_t magic; - - if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { - LOG("read failed"); - errno = EINVAL; - return -1; - } - - /* Request - [ 0 .. 3] magic (NBD_REQUEST_MAGIC) - [ 4 .. 7] type (0 == READ, 1 == WRITE) - [ 8 .. 15] handle - [16 .. 23] from - [24 .. 27] len - */ - - magic = be32_to_cpup((uint32_t*)buf); - request->type = be32_to_cpup((uint32_t*)(buf + 4)); - request->handle = be64_to_cpup((uint64_t*)(buf + 8)); - request->from = be64_to_cpup((uint64_t*)(buf + 16)); - request->len = be32_to_cpup((uint32_t*)(buf + 24)); - - TRACE("Got request: " - "{ magic = 0x%x, .type = %d, from = %" PRIu64" , len = %u }", - magic, request->type, request->from, request->len); - - if (magic != NBD_REQUEST_MAGIC) { - LOG("invalid magic (got 0x%x)", magic); - errno = EINVAL; - return -1; - } - return 0; + uint8_t buf[4 + 4 + 8 + 8 + 4]; + uint32_t magic; + + if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { + LOG("read failed"); + errno = EINVAL; + return -1; + } + + /* Request + [ 0 .. 3] magic (NBD_REQUEST_MAGIC) + [ 4 .. 7] type (0 == READ, 1 == WRITE) + [ 8 .. 15] handle + [16 .. 23] from + [24 .. 27] len + */ + + magic = be32_to_cpup((uint32_t*)buf); + request->type = be32_to_cpup((uint32_t*)(buf + 4)); + request->handle = be64_to_cpup((uint64_t*)(buf + 8)); + request->from = be64_to_cpup((uint64_t*)(buf + 16)); + request->len = be32_to_cpup((uint32_t*)(buf + 24)); + + TRACE("Got request: " + "{ magic = 0x%x, .type = %d, from = %" PRIu64" , len = %u }", + magic, request->type, request->from, request->len); + + if (magic != NBD_REQUEST_MAGIC) { + LOG("invalid magic (got 0x%x)", magic); + errno = EINVAL; + return -1; + } + return 0; } int nbd_receive_reply(int csock, struct nbd_reply *reply) { - uint8_t buf[NBD_REPLY_SIZE]; - uint32_t magic; - - memset(buf, 0xAA, sizeof(buf)); - - if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { - LOG("read failed"); - errno = EINVAL; - return -1; - } - - /* Reply - [ 0 .. 3] magic (NBD_REPLY_MAGIC) - [ 4 .. 7] error (0 == no error) - [ 7 .. 15] handle - */ - - magic = be32_to_cpup((uint32_t*)buf); - reply->error = be32_to_cpup((uint32_t*)(buf + 4)); - reply->handle = be64_to_cpup((uint64_t*)(buf + 8)); - - TRACE("Got reply: " - "{ magic = 0x%x, .error = %d, handle = %" PRIu64" }", - magic, reply->error, reply->handle); - - if (magic != NBD_REPLY_MAGIC) { - LOG("invalid magic (got 0x%x)", magic); - errno = EINVAL; - return -1; - } - return 0; + uint8_t buf[NBD_REPLY_SIZE]; + uint32_t magic; + + memset(buf, 0xAA, sizeof(buf)); + + if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { + LOG("read failed"); + errno = EINVAL; + return -1; + } + + /* Reply + [ 0 .. 3] magic (NBD_REPLY_MAGIC) + [ 4 .. 7] error (0 == no error) + [ 7 .. 15] handle + */ + + magic = be32_to_cpup((uint32_t*)buf); + reply->error = be32_to_cpup((uint32_t*)(buf + 4)); + reply->handle = be64_to_cpup((uint64_t*)(buf + 8)); + + TRACE("Got reply: " + "{ magic = 0x%x, .error = %d, handle = %" PRIu64" }", + magic, reply->error, reply->handle); + + if (magic != NBD_REPLY_MAGIC) { + LOG("invalid magic (got 0x%x)", magic); + errno = EINVAL; + return -1; + } + return 0; } static int nbd_send_reply(int csock, struct nbd_reply *reply) { - uint8_t buf[4 + 4 + 8]; - - /* Reply - [ 0 .. 3] magic (NBD_REPLY_MAGIC) - [ 4 .. 7] error (0 == no error) - [ 7 .. 15] handle - */ - cpu_to_be32w((uint32_t*)buf, NBD_REPLY_MAGIC); - cpu_to_be32w((uint32_t*)(buf + 4), reply->error); - cpu_to_be64w((uint64_t*)(buf + 8), reply->handle); - - TRACE("Sending response to client"); - - if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { - LOG("writing to socket failed"); - errno = EINVAL; - return -1; - } - return 0; + uint8_t buf[4 + 4 + 8]; + + /* Reply + [ 0 .. 3] magic (NBD_REPLY_MAGIC) + [ 4 .. 7] error (0 == no error) + [ 7 .. 15] handle + */ + cpu_to_be32w((uint32_t*)buf, NBD_REPLY_MAGIC); + cpu_to_be32w((uint32_t*)(buf + 4), reply->error); + cpu_to_be64w((uint64_t*)(buf + 8), reply->handle); + + TRACE("Sending response to client"); + + if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { + LOG("writing to socket failed"); + errno = EINVAL; + return -1; + } + return 0; } int nbd_trip(BlockDriverState *bs, int csock, off_t size, uint64_t dev_offset, off_t *offset, bool readonly, uint8_t *data, int data_size) { - struct nbd_request request; - struct nbd_reply reply; - - TRACE("Reading request."); - - if (nbd_receive_request(csock, &request) == -1) - return -1; - - if (request.len + NBD_REPLY_SIZE > data_size) { - LOG("len (%u) is larger than max len (%u)", - request.len + NBD_REPLY_SIZE, data_size); - errno = EINVAL; - return -1; - } - - if ((request.from + request.len) < request.from) { - LOG("integer overflow detected! " - "you're probably being attacked"); - errno = EINVAL; - return -1; - } - - if ((request.from + request.len) > size) { - LOG("From: %" PRIu64 ", Len: %u, Size: %" PRIu64 - ", Offset: %" PRIu64 "\n", + struct nbd_request request; + struct nbd_reply reply; + + TRACE("Reading request."); + + if (nbd_receive_request(csock, &request) == -1) + return -1; + + if (request.len + NBD_REPLY_SIZE > data_size) { + LOG("len (%u) is larger than max len (%u)", + request.len + NBD_REPLY_SIZE, data_size); + errno = EINVAL; + return -1; + } + + if ((request.from + request.len) < request.from) { + LOG("integer overflow detected! " + "you're probably being attacked"); + errno = EINVAL; + return -1; + } + + if ((request.from + request.len) > size) { + LOG("From: %" PRIu64 ", Len: %u, Size: %" PRIu64 + ", Offset: %" PRIu64 "\n", request.from, request.len, (uint64_t)size, dev_offset); - LOG("requested operation past EOF--bad client?"); - errno = EINVAL; - return -1; - } - - TRACE("Decoding type"); - - reply.handle = request.handle; - reply.error = 0; - - switch (request.type) { - case NBD_CMD_READ: - TRACE("Request type is READ"); - - if (bdrv_read(bs, (request.from + dev_offset) / 512, - data + NBD_REPLY_SIZE, - request.len / 512) == -1) { - LOG("reading from file failed"); - errno = EINVAL; - return -1; - } - *offset += request.len; - - TRACE("Read %u byte(s)", request.len); - - /* Reply - [ 0 .. 3] magic (NBD_REPLY_MAGIC) - [ 4 .. 7] error (0 == no error) - [ 7 .. 15] handle - */ - - cpu_to_be32w((uint32_t*)data, NBD_REPLY_MAGIC); - cpu_to_be32w((uint32_t*)(data + 4), reply.error); - cpu_to_be64w((uint64_t*)(data + 8), reply.handle); - - TRACE("Sending data to client"); - - if (write_sync(csock, data, - request.len + NBD_REPLY_SIZE) != - request.len + NBD_REPLY_SIZE) { - LOG("writing to socket failed"); - errno = EINVAL; - return -1; - } - break; - case NBD_CMD_WRITE: - TRACE("Request type is WRITE"); - - TRACE("Reading %u byte(s)", request.len); - - if (read_sync(csock, data, request.len) != request.len) { - LOG("reading from socket failed"); - errno = EINVAL; - return -1; - } - - if (readonly) { - TRACE("Server is read-only, return error"); - reply.error = 1; - } else { - TRACE("Writing to device"); - - if (bdrv_write(bs, (request.from + dev_offset) / 512, - data, request.len / 512) == -1) { - LOG("writing to file failed"); - errno = EINVAL; - return -1; - } - - *offset += request.len; - } - - if (nbd_send_reply(csock, &reply) == -1) - return -1; - break; - case NBD_CMD_DISC: - TRACE("Request type is DISCONNECT"); - errno = 0; - return 1; - default: - LOG("invalid request type (%u) received", request.type); - errno = EINVAL; - return -1; - } - - TRACE("Request/Reply complete"); - - return 0; + LOG("requested operation past EOF--bad client?"); + errno = EINVAL; + return -1; + } + + TRACE("Decoding type"); + + reply.handle = request.handle; + reply.error = 0; + + switch (request.type) { + case NBD_CMD_READ: + TRACE("Request type is READ"); + + if (bdrv_read(bs, (request.from + dev_offset) / 512, + data + NBD_REPLY_SIZE, + request.len / 512) == -1) { + LOG("reading from file failed"); + errno = EINVAL; + return -1; + } + *offset += request.len; + + TRACE("Read %u byte(s)", request.len); + + /* Reply + [ 0 .. 3] magic (NBD_REPLY_MAGIC) + [ 4 .. 7] error (0 == no error) + [ 7 .. 15] handle + */ + + cpu_to_be32w((uint32_t*)data, NBD_REPLY_MAGIC); + cpu_to_be32w((uint32_t*)(data + 4), reply.error); + cpu_to_be64w((uint64_t*)(data + 8), reply.handle); + + TRACE("Sending data to client"); + + if (write_sync(csock, data, + request.len + NBD_REPLY_SIZE) != + request.len + NBD_REPLY_SIZE) { + LOG("writing to socket failed"); + errno = EINVAL; + return -1; + } + break; + case NBD_CMD_WRITE: + TRACE("Request type is WRITE"); + + TRACE("Reading %u byte(s)", request.len); + + if (read_sync(csock, data, request.len) != request.len) { + LOG("reading from socket failed"); + errno = EINVAL; + return -1; + } + + if (readonly) { + TRACE("Server is read-only, return error"); + reply.error = 1; + } else { + TRACE("Writing to device"); + + if (bdrv_write(bs, (request.from + dev_offset) / 512, + data, request.len / 512) == -1) { + LOG("writing to file failed"); + errno = EINVAL; + return -1; + } + + *offset += request.len; + } + + if (nbd_send_reply(csock, &reply) == -1) + return -1; + break; + case NBD_CMD_DISC: + TRACE("Request type is DISCONNECT"); + errno = 0; + return 1; + default: + LOG("invalid request type (%u) received", request.type); + errno = EINVAL; + return -1; + } + + TRACE("Request/Reply complete"); + + return 0; } |