/**************************************************************************** * fs/nfs/nfs_util.c * * Copyright (C) 2012-2013 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #include #include #include "rpc.h" #include "nfs.h" #include "nfs_proto.h" #include "nfs_mount.h" #include "nfs_node.h" #include "xdr_subs.h" /**************************************************************************** * Private Functions ****************************************************************************/ static inline int nfs_pathsegment(FAR const char **path, FAR char *buffer, FAR char *terminator) { FAR const char *src = *path; FAR char *dest = buffer; int nbytes = 0; char ch; /* Loop until the name is successfully parsed or an error occurs */ for (; ; ) { /* Get the next byte from the path */ ch = *src++; /* Check if this the last byte in this segment name */ if (ch == '\0' || ch == '/') { /* This logic just suppors "//" sequences in the path name */ if (ch == '\0' || nbytes > 0) { /* NULL terminate the parsed path segment */ *dest = '\0'; /* Return next path and the terminating character */ *terminator = ch; *path = src; return OK; } /* Just skip over any leading '/' characters */ } else if (nbytes >= NAME_MAX) { fdbg("File name segment is too long: %d\n", *path); return EFBIG; } else { /* Save next character in the accumulated name */ *dest++ = ch; nbytes++; } } } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: nfs_semtake ****************************************************************************/ void nfs_semtake(struct nfsmount *nmp) { /* Take the semaphore (perhaps waiting) */ while (sem_wait(&nmp->nm_sem) != 0) { /* The only case that an error should occur here is if * the wait was awakened by a signal. */ ASSERT(*get_errno_ptr() == EINTR); } } /**************************************************************************** * Name: nfs_semgive ****************************************************************************/ void nfs_semgive(struct nfsmount *nmp) { sem_post(&nmp->nm_sem); } /**************************************************************************** * Name: nfs_checkmount * * Desciption: Check if the mountpoint is still valid. * * The caller should hold the mountpoint semaphore * ****************************************************************************/ int nfs_checkmount(struct nfsmount *nmp) { struct nfsnode *file; /* If the nm_mounted flag is false, then we have already handled the loss * of the mount. */ DEBUGASSERT(nmp); if (!nmp->nm_mounted) { /* Make sure that this is flagged in every opened file */ for (file = nmp->nm_head; file; file = file->n_next) { file->n_flags &= ~NFSNODE_OPEN; } return -ENODEV; } return 0; } /**************************************************************************** * Name: nfs_request * * Desciption: * Perform the NFS request. On successful receipt, it verifies the NFS level of the * returned values. * * Return Value: * Zero on success; a positive errno value on failure. * ****************************************************************************/ int nfs_request(struct nfsmount *nmp, int procnum, FAR void *request, size_t reqlen, FAR void *response, size_t resplen) { struct rpcclnt *clnt = nmp->nm_rpcclnt; struct nfs_reply_header replyh; int error; tryagain: error = rpcclnt_request(clnt, procnum, NFS_PROG, NFS_VER3, request, reqlen, response, resplen); if (error != 0) { fdbg("ERROR: rpcclnt_request failed: %d\n", error); return error; } memcpy(&replyh, response, sizeof(struct nfs_reply_header)); if (replyh.nfs_status != 0) { if (fxdr_unsigned(uint32_t, replyh.nfs_status) > 32) { error = EOPNOTSUPP; } else { /* NFS_ERRORS are the same as NuttX errno values */ error = fxdr_unsigned(uint32_t, replyh.nfs_status); } return error; } if (replyh.rpc_verfi.authtype != 0) { error = fxdr_unsigned(int, replyh.rpc_verfi.authtype); if (error == EAGAIN) { error = 0; goto tryagain; } fdbg("ERROR: NFS error %d from server\n", error); return error; } fvdbg("NFS_SUCCESS\n"); return OK; } /**************************************************************************** * Name: nfs_lookup * * Desciption: * Given a directory file handle, and the path to file in the directory, * return the file handle of the path and attributes of both the file and * the directory containing the file. * * NOTE: The LOOKUP call differs from other RPC messages in that the * call message is variable length, depending upon the size of the path * name. * ****************************************************************************/ int nfs_lookup(struct nfsmount *nmp, FAR const char *filename, FAR struct file_handle *fhandle, FAR struct nfs_fattr *obj_attributes, FAR struct nfs_fattr *dir_attributes) { FAR uint32_t *ptr; uint32_t value; int reqlen; int namelen; int error = 0; DEBUGASSERT(nmp && filename && fhandle); /* Get the length of the string to be sent */ namelen = strlen(filename); if (namelen > NAME_MAX) { fdbg("Length of the string is too big: %d\n", namelen); return E2BIG; } /* Initialize the request */ ptr = (FAR uint32_t *)&nmp->nm_msgbuffer.lookup.lookup; reqlen = 0; /* Copy the variable length, directory file handle */ *ptr++ = txdr_unsigned(fhandle->length); reqlen += sizeof(uint32_t); memcpy(ptr, &fhandle->handle, fhandle->length); reqlen += fhandle->length; ptr += uint32_increment(fhandle->length); /* Copy the variable-length file name */ *ptr++ = txdr_unsigned(namelen); reqlen += sizeof(uint32_t); memcpy(ptr, filename, namelen); reqlen += uint32_alignup(namelen); /* Request LOOKUP from the server */ nfs_statistics(NFSPROC_LOOKUP); error = nfs_request(nmp, NFSPROC_LOOKUP, (FAR void *)&nmp->nm_msgbuffer.lookup, reqlen, (FAR void *)nmp->nm_iobuffer, nmp->nm_buflen); if (error) { fdbg("ERROR: nfs_request failed: %d\n", error); return error; } /* Return the data to the caller's buffers. NOTE: Here we ignore the * the exact layout of the rpc_reply_lookup structure. File handles * may differ in size whereas struct rpc_reply_lookup uses a fixed size. */ ptr = (FAR uint32_t *)&((FAR struct rpc_reply_lookup *)nmp->nm_iobuffer)->lookup; /* Get the length of the file handle */ value = *ptr++; value = fxdr_unsigned(uint32_t, value); if (value > NFSX_V3FHMAX) { fdbg("ERROR: Bad file handle length: %d\n", value); return EIO; } /* Return the file handle */ fhandle->length = value; memcpy(&fhandle->handle, ptr, value); ptr += uint32_increment(value); /* Check if there are object attributes and, if so, copy them to the user * buffer */ value = *ptr++; if (value) { if (obj_attributes) { memcpy(obj_attributes, ptr, sizeof(struct nfs_fattr)); } ptr += uint32_increment(sizeof(struct nfs_fattr)); } /* Check if there are directory attributes and, if so, copy them to the * user buffer */ value = *ptr++; if (value && dir_attributes) { memcpy(dir_attributes, ptr, sizeof(struct nfs_fattr)); } return OK; } /**************************************************************************** * Name: nfs_findnode * * Desciption: * Given a path to something that may or may not be in the file system, * return the handle of the directory entry of the requested object. * * Return Value: * Zero on success; a positive errno value on failure. * ****************************************************************************/ int nfs_findnode(struct nfsmount *nmp, FAR const char *relpath, FAR struct file_handle *fhandle, FAR struct nfs_fattr *obj_attributes, FAR struct nfs_fattr *dir_attributes) { FAR const char *path = relpath; char buffer[NAME_MAX+1]; char terminator; uint32_t tmp; int error; /* Start with the file handle of the root directory. */ fhandle->length = nmp->nm_fhsize; memcpy(&fhandle->handle, &nmp->nm_fh, nmp->nm_fhsize); /* If no path was provided, then the root directory must be exactly what * the caller is looking for. */ if (*path == '\0' || strlen(path) == 0) { /* Return the root directory attributes */ if (obj_attributes) { memcpy(obj_attributes, &nmp->nm_fattr, sizeof(struct nfs_fattr)); } if (dir_attributes) { memcpy(dir_attributes, &nmp->nm_fattr, sizeof(struct nfs_fattr)); } return OK; } /* This is not the root directory. Loop until the directory entry corresponding * to the path is found. */ for (; ; ) { /* Extract the next path segment name. */ error = nfs_pathsegment(&path, buffer, &terminator); if (error != OK) { /* The filename segment contains is too long. */ fdbg("nfs_pathsegment of \"%s\" failed after \"%s\": %d\n", relpath, buffer, error); return error; } /* Look-up this path segment */ error = nfs_lookup(nmp, buffer, fhandle, obj_attributes, dir_attributes); if (error != OK) { fdbg("nfs_lookup of \"%s\" failed at \"%s\": %d\n", relpath, buffer, error); return error; } /* If the terminator character in the path was the end of the string * then we have successfully found the directory entry that describes * the path. */ if (!terminator) { /* Return success meaning that the description the matching * directory entry is in fhandle, obj_attributes, and dir_attributes. */ return OK; } /* No.. then we have found one of the intermediate directories on * the way to the final path target. In this case, make sure * the thing that we found is, indeed, a directory. */ tmp = fxdr_unsigned(uint32_t, obj_attributes->fa_type); if (tmp != NFDIR) { /* Ooops.. we found something else */ fdbg("ERROR: Intermediate segment \"%s\" of \'%s\" is not a directory\n", buffer, path); return ENOTDIR; } } } /**************************************************************************** * Name: nfs_finddir * * Desciption: * Given a path to something that may or may not be in the file system, * return the handle of the entry of the directory containing the requested * object. * * Return Value: * Zero on success; a positive errno value on failure. * ****************************************************************************/ int nfs_finddir(struct nfsmount *nmp, FAR const char *relpath, FAR struct file_handle *fhandle, FAR struct nfs_fattr *attributes, FAR char *filename) { FAR const char *path = relpath; uint32_t tmp; char terminator; int error; /* Verify that a path was provided */ if (*path == '\0' || strlen(path) == 0) { /* Return the root directory attributes */ return ENOENT; } /* Start with the file handle of the root directory. */ fhandle->length = nmp->nm_fhsize; memcpy(&fhandle->handle, &nmp->nm_fh, nmp->nm_fhsize); memcpy(attributes, &nmp->nm_fattr, sizeof(struct nfs_fattr)); /* Loop until the directory entry containing the path is found. */ for (; ; ) { /* Extract the next path segment name. */ error = nfs_pathsegment(&path, filename, &terminator); if (error != OK) { /* The filename segment contains is too long. */ fdbg("nfs_pathsegment of \"%s\" failed after \"%s\": %d\n", relpath, filename, error); return error; } /* If the terminator character in the path was the end of the string * then we have successfully found the directory that contains the name * of interest. */ if (!terminator) { /* Return success meaning that the description of the directory * containing the object is in fhandle and attributes. */ return OK; } /* Look-up the next path segment */ error = nfs_lookup(nmp, filename, fhandle, attributes, NULL); if (error != OK) { fdbg("nfs_lookup of \"%s\" failed at \"%s\": %d\n", relpath, filename, error); return error; } /* Make sure the thing that we found is, indeed, a directory. */ tmp = fxdr_unsigned(uint32_t, attributes->fa_type); if (tmp != NFDIR) { /* Ooops.. we found something else */ fdbg("ERROR: Intermediate segment \"%s\" of \'%s\" is not a directory\n", filename, path); return ENOTDIR; } } } /**************************************************************************** * Name: nfs_attrupdate * * Desciption: * Update file attributes on write or after the file is modified. * * Return Value: * None. * ****************************************************************************/ void nfs_attrupdate(FAR struct nfsnode *np, FAR struct nfs_fattr *attributes) { /* Save a few of the files attribute values in file structur (host order) */ np->n_type = fxdr_unsigned(uint32_t, attributes->fa_type); np->n_size = fxdr_hyper(&attributes->fa_size); fxdr_nfsv3time(&attributes->fa_mtime, &np->n_mtime) np->n_ctime = fxdr_hyper(&attributes->fa_ctime); }