diff options
Diffstat (limited to 'ANDROID_3.4.5/fs/nfs/nfs4namespace.c')
-rw-r--r-- | ANDROID_3.4.5/fs/nfs/nfs4namespace.c | 343 |
1 files changed, 343 insertions, 0 deletions
diff --git a/ANDROID_3.4.5/fs/nfs/nfs4namespace.c b/ANDROID_3.4.5/fs/nfs/nfs4namespace.c new file mode 100644 index 00000000..a7f3dedc --- /dev/null +++ b/ANDROID_3.4.5/fs/nfs/nfs4namespace.c @@ -0,0 +1,343 @@ +/* + * linux/fs/nfs/nfs4namespace.c + * + * Copyright (C) 2005 Trond Myklebust <Trond.Myklebust@netapp.com> + * - Modified by David Howells <dhowells@redhat.com> + * + * NFSv4 namespace + */ + +#include <linux/dcache.h> +#include <linux/mount.h> +#include <linux/namei.h> +#include <linux/nfs_fs.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/sunrpc/clnt.h> +#include <linux/vfs.h> +#include <linux/inet.h> +#include "internal.h" +#include "nfs4_fs.h" +#include "dns_resolve.h" + +#define NFSDBG_FACILITY NFSDBG_VFS + +/* + * Convert the NFSv4 pathname components into a standard posix path. + * + * Note that the resulting string will be placed at the end of the buffer + */ +static inline char *nfs4_pathname_string(const struct nfs4_pathname *pathname, + char *buffer, ssize_t buflen) +{ + char *end = buffer + buflen; + int n; + + *--end = '\0'; + buflen--; + + n = pathname->ncomponents; + while (--n >= 0) { + const struct nfs4_string *component = &pathname->components[n]; + buflen -= component->len + 1; + if (buflen < 0) + goto Elong; + end -= component->len; + memcpy(end, component->data, component->len); + *--end = '/'; + } + return end; +Elong: + return ERR_PTR(-ENAMETOOLONG); +} + +/* + * return the path component of "<server>:<path>" + * nfspath - the "<server>:<path>" string + * end - one past the last char that could contain "<server>:" + * returns NULL on failure + */ +static char *nfs_path_component(const char *nfspath, const char *end) +{ + char *p; + + if (*nfspath == '[') { + /* parse [] escaped IPv6 addrs */ + p = strchr(nfspath, ']'); + if (p != NULL && ++p < end && *p == ':') + return p + 1; + } else { + /* otherwise split on first colon */ + p = strchr(nfspath, ':'); + if (p != NULL && p < end) + return p + 1; + } + return NULL; +} + +/* + * Determine the mount path as a string + */ +static char *nfs4_path(struct dentry *dentry, char *buffer, ssize_t buflen) +{ + char *limit; + char *path = nfs_path(&limit, dentry, buffer, buflen); + if (!IS_ERR(path)) { + char *path_component = nfs_path_component(path, limit); + if (path_component) + return path_component; + } + return path; +} + +/* + * Check that fs_locations::fs_root [RFC3530 6.3] is a prefix for what we + * believe to be the server path to this dentry + */ +static int nfs4_validate_fspath(struct dentry *dentry, + const struct nfs4_fs_locations *locations, + char *page, char *page2) +{ + const char *path, *fs_path; + + path = nfs4_path(dentry, page, PAGE_SIZE); + if (IS_ERR(path)) + return PTR_ERR(path); + + fs_path = nfs4_pathname_string(&locations->fs_path, page2, PAGE_SIZE); + if (IS_ERR(fs_path)) + return PTR_ERR(fs_path); + + if (strncmp(path, fs_path, strlen(fs_path)) != 0) { + dprintk("%s: path %s does not begin with fsroot %s\n", + __func__, path, fs_path); + return -ENOENT; + } + + return 0; +} + +static size_t nfs_parse_server_name(char *string, size_t len, + struct sockaddr *sa, size_t salen, struct nfs_server *server) +{ + struct net *net = rpc_net_ns(server->client); + ssize_t ret; + + ret = rpc_pton(net, string, len, sa, salen); + if (ret == 0) { + ret = nfs_dns_resolve_name(net, string, len, sa, salen); + if (ret < 0) + ret = 0; + } + return ret; +} + +static rpc_authflavor_t nfs4_negotiate_security(struct inode *inode, struct qstr *name) +{ + struct page *page; + struct nfs4_secinfo_flavors *flavors; + rpc_authflavor_t flavor; + int err; + + page = alloc_page(GFP_KERNEL); + if (!page) + return -ENOMEM; + flavors = page_address(page); + + err = nfs4_proc_secinfo(inode, name, flavors); + if (err < 0) { + flavor = err; + goto out; + } + + flavor = nfs_find_best_sec(flavors); + +out: + put_page(page); + return flavor; +} + +/* + * Please call rpc_shutdown_client() when you are done with this client. + */ +struct rpc_clnt *nfs4_create_sec_client(struct rpc_clnt *clnt, struct inode *inode, + struct qstr *name) +{ + struct rpc_clnt *clone; + struct rpc_auth *auth; + rpc_authflavor_t flavor; + + flavor = nfs4_negotiate_security(inode, name); + if (flavor < 0) + return ERR_PTR(flavor); + + clone = rpc_clone_client(clnt); + if (IS_ERR(clone)) + return clone; + + auth = rpcauth_create(flavor, clone); + if (!auth) { + rpc_shutdown_client(clone); + clone = ERR_PTR(-EIO); + } + + return clone; +} + +static struct vfsmount *try_location(struct nfs_clone_mount *mountdata, + char *page, char *page2, + const struct nfs4_fs_location *location) +{ + const size_t addr_bufsize = sizeof(struct sockaddr_storage); + struct vfsmount *mnt = ERR_PTR(-ENOENT); + char *mnt_path; + unsigned int maxbuflen; + unsigned int s; + + mnt_path = nfs4_pathname_string(&location->rootpath, page2, PAGE_SIZE); + if (IS_ERR(mnt_path)) + return ERR_CAST(mnt_path); + mountdata->mnt_path = mnt_path; + maxbuflen = mnt_path - 1 - page2; + + mountdata->addr = kmalloc(addr_bufsize, GFP_KERNEL); + if (mountdata->addr == NULL) + return ERR_PTR(-ENOMEM); + + for (s = 0; s < location->nservers; s++) { + const struct nfs4_string *buf = &location->servers[s]; + + if (buf->len <= 0 || buf->len >= maxbuflen) + continue; + + if (memchr(buf->data, IPV6_SCOPE_DELIMITER, buf->len)) + continue; + + mountdata->addrlen = nfs_parse_server_name(buf->data, buf->len, + mountdata->addr, addr_bufsize, + NFS_SB(mountdata->sb)); + if (mountdata->addrlen == 0) + continue; + + rpc_set_port(mountdata->addr, NFS_PORT); + + memcpy(page2, buf->data, buf->len); + page2[buf->len] = '\0'; + mountdata->hostname = page2; + + snprintf(page, PAGE_SIZE, "%s:%s", + mountdata->hostname, + mountdata->mnt_path); + + mnt = vfs_kern_mount(&nfs4_referral_fs_type, 0, page, mountdata); + if (!IS_ERR(mnt)) + break; + } + kfree(mountdata->addr); + return mnt; +} + +/** + * nfs_follow_referral - set up mountpoint when hitting a referral on moved error + * @dentry - parent directory + * @locations - array of NFSv4 server location information + * + */ +static struct vfsmount *nfs_follow_referral(struct dentry *dentry, + const struct nfs4_fs_locations *locations) +{ + struct vfsmount *mnt = ERR_PTR(-ENOENT); + struct nfs_clone_mount mountdata = { + .sb = dentry->d_sb, + .dentry = dentry, + .authflavor = NFS_SB(dentry->d_sb)->client->cl_auth->au_flavor, + }; + char *page = NULL, *page2 = NULL; + int loc, error; + + if (locations == NULL || locations->nlocations <= 0) + goto out; + + dprintk("%s: referral at %s/%s\n", __func__, + dentry->d_parent->d_name.name, dentry->d_name.name); + + page = (char *) __get_free_page(GFP_USER); + if (!page) + goto out; + + page2 = (char *) __get_free_page(GFP_USER); + if (!page2) + goto out; + + /* Ensure fs path is a prefix of current dentry path */ + error = nfs4_validate_fspath(dentry, locations, page, page2); + if (error < 0) { + mnt = ERR_PTR(error); + goto out; + } + + for (loc = 0; loc < locations->nlocations; loc++) { + const struct nfs4_fs_location *location = &locations->locations[loc]; + + if (location == NULL || location->nservers <= 0 || + location->rootpath.ncomponents == 0) + continue; + + mnt = try_location(&mountdata, page, page2, location); + if (!IS_ERR(mnt)) + break; + } + +out: + free_page((unsigned long) page); + free_page((unsigned long) page2); + dprintk("%s: done\n", __func__); + return mnt; +} + +/* + * nfs_do_refmount - handle crossing a referral on server + * @dentry - dentry of referral + * + */ +struct vfsmount *nfs_do_refmount(struct rpc_clnt *client, struct dentry *dentry) +{ + struct vfsmount *mnt = ERR_PTR(-ENOMEM); + struct dentry *parent; + struct nfs4_fs_locations *fs_locations = NULL; + struct page *page; + int err; + + /* BUG_ON(IS_ROOT(dentry)); */ + dprintk("%s: enter\n", __func__); + + page = alloc_page(GFP_KERNEL); + if (page == NULL) + goto out; + + fs_locations = kmalloc(sizeof(struct nfs4_fs_locations), GFP_KERNEL); + if (fs_locations == NULL) + goto out_free; + + /* Get locations */ + mnt = ERR_PTR(-ENOENT); + + parent = dget_parent(dentry); + dprintk("%s: getting locations for %s/%s\n", + __func__, parent->d_name.name, dentry->d_name.name); + + err = nfs4_proc_fs_locations(client, parent->d_inode, &dentry->d_name, fs_locations, page); + dput(parent); + if (err != 0 || + fs_locations->nlocations <= 0 || + fs_locations->fs_path.ncomponents <= 0) + goto out_free; + + mnt = nfs_follow_referral(dentry, fs_locations); +out_free: + __free_page(page); + kfree(fs_locations); +out: + dprintk("%s: done\n", __func__); + return mnt; +} |