diff options
Diffstat (limited to 'fs/cifs/cifs_dfs_ref.c')
-rw-r--r-- | fs/cifs/cifs_dfs_ref.c | 111 |
1 files changed, 79 insertions, 32 deletions
diff --git a/fs/cifs/cifs_dfs_ref.c b/fs/cifs/cifs_dfs_ref.c index d2c8eef84f3..85c0a74d034 100644 --- a/fs/cifs/cifs_dfs_ref.c +++ b/fs/cifs/cifs_dfs_ref.c @@ -106,7 +106,8 @@ static char *cifs_get_share_name(const char *node_name) /** * compose_mount_options - creates mount options for refferral * @sb_mountdata: parent/root DFS mount options (template) - * @ref_unc: refferral server UNC + * @dentry: point where we are going to mount + * @ref: server's referral * @devname: pointer for saving device name * * creates mount options for submount based on template options sb_mountdata @@ -116,33 +117,39 @@ static char *cifs_get_share_name(const char *node_name) * Caller is responcible for freeing retunrned value if it is not error. */ static char *compose_mount_options(const char *sb_mountdata, - const char *ref_unc, + struct dentry *dentry, + const struct dfs_info3_param *ref, char **devname) { int rc; - char *mountdata; + char *mountdata = NULL; int md_len; char *tkn_e; char *srvIP = NULL; char sep = ','; int off, noff; + char *fullpath; if (sb_mountdata == NULL) return ERR_PTR(-EINVAL); - *devname = cifs_get_share_name(ref_unc); + *devname = cifs_get_share_name(ref->node_name); rc = dns_resolve_server_name_to_ip(*devname, &srvIP); if (rc != 0) { - cERROR(1, ("%s: Failed to resolve server part of %s to IP", - __func__, *devname)); - mountdata = ERR_PTR(rc); - goto compose_mount_options_out; + cERROR(1, ("%s: Failed to resolve server part of %s to IP: %d", + __func__, *devname, rc));; + goto compose_mount_options_err; } - md_len = strlen(sb_mountdata) + strlen(srvIP) + strlen(ref_unc) + 3; + /* md_len = strlen(...) + 12 for 'sep+prefixpath=' + * assuming that we have 'unc=' and 'ip=' in + * the original sb_mountdata + */ + md_len = strlen(sb_mountdata) + strlen(srvIP) + + strlen(ref->node_name) + 12; mountdata = kzalloc(md_len+1, GFP_KERNEL); if (mountdata == NULL) { - mountdata = ERR_PTR(-ENOMEM); - goto compose_mount_options_out; + rc = -ENOMEM; + goto compose_mount_options_err; } /* copy all options except of unc,ip,prefixpath */ @@ -152,53 +159,87 @@ static char *compose_mount_options(const char *sb_mountdata, strncpy(mountdata, sb_mountdata, 5); off += 5; } - while ((tkn_e = strchr(sb_mountdata+off, sep))) { - noff = (tkn_e - (sb_mountdata+off)) + 1; - if (strnicmp(sb_mountdata+off, "unc=", 4) == 0) { + + do { + tkn_e = strchr(sb_mountdata + off, sep); + if (tkn_e == NULL) + noff = strlen(sb_mountdata + off); + else + noff = tkn_e - (sb_mountdata + off) + 1; + + if (strnicmp(sb_mountdata + off, "unc=", 4) == 0) { off += noff; continue; } - if (strnicmp(sb_mountdata+off, "ip=", 3) == 0) { + if (strnicmp(sb_mountdata + off, "ip=", 3) == 0) { off += noff; continue; } - if (strnicmp(sb_mountdata+off, "prefixpath=", 3) == 0) { + if (strnicmp(sb_mountdata + off, "prefixpath=", 11) == 0) { off += noff; continue; } - strncat(mountdata, sb_mountdata+off, noff); + strncat(mountdata, sb_mountdata + off, noff); off += noff; - } - strcat(mountdata, sb_mountdata+off); + } while (tkn_e); + strcat(mountdata, sb_mountdata + off); mountdata[md_len] = '\0'; /* copy new IP and ref share name */ - strcat(mountdata, ",ip="); + if (mountdata[strlen(mountdata) - 1] != sep) + strncat(mountdata, &sep, 1); + strcat(mountdata, "ip="); strcat(mountdata, srvIP); - strcat(mountdata, ",unc="); + strncat(mountdata, &sep, 1); + strcat(mountdata, "unc="); strcat(mountdata, *devname); /* find & copy prefixpath */ - tkn_e = strchr(ref_unc+2, '\\'); - if (tkn_e) { - tkn_e = strchr(tkn_e+1, '\\'); - if (tkn_e) { - strcat(mountdata, ",prefixpath="); - strcat(mountdata, tkn_e+1); - } + tkn_e = strchr(ref->node_name + 2, '\\'); + if (tkn_e == NULL) { + /* invalid unc, missing share name*/ + rc = -EINVAL; + goto compose_mount_options_err; } + /* + * this function gives us a path with a double backslash prefix. We + * require a single backslash for DFS. Temporarily increment fullpath + * to put it in the proper form and decrement before freeing it. + */ + fullpath = build_path_from_dentry(dentry); + if (!fullpath) { + rc = -ENOMEM; + goto compose_mount_options_err; + } + ++fullpath; + tkn_e = strchr(tkn_e + 1, '\\'); + if (tkn_e || (strlen(fullpath) - ref->path_consumed)) { + strncat(mountdata, &sep, 1); + strcat(mountdata, "prefixpath="); + if (tkn_e) + strcat(mountdata, tkn_e + 1); + strcat(mountdata, fullpath + ref->path_consumed); + } + --fullpath; + kfree(fullpath); + /*cFYI(1,("%s: parent mountdata: %s", __func__,sb_mountdata));*/ /*cFYI(1, ("%s: submount mountdata: %s", __func__, mountdata ));*/ compose_mount_options_out: kfree(srvIP); return mountdata; + +compose_mount_options_err: + kfree(mountdata); + mountdata = ERR_PTR(rc); + goto compose_mount_options_out; } static struct vfsmount *cifs_dfs_do_refmount(const struct vfsmount *mnt_parent, - struct dentry *dentry, char *ref_unc) + struct dentry *dentry, const struct dfs_info3_param *ref) { struct cifs_sb_info *cifs_sb; struct vfsmount *mnt; @@ -207,7 +248,7 @@ static struct vfsmount *cifs_dfs_do_refmount(const struct vfsmount *mnt_parent, cifs_sb = CIFS_SB(dentry->d_inode->i_sb); mountdata = compose_mount_options(cifs_sb->mountdata, - ref_unc, &devname); + dentry, ref, &devname); if (IS_ERR(mountdata)) return (struct vfsmount *)mountdata; @@ -286,13 +327,19 @@ cifs_dfs_follow_mountpoint(struct dentry *dentry, struct nameidata *nd) goto out_err; } + /* + * The MSDFS spec states that paths in DFS referral requests and + * responses must be prefixed by a single '\' character instead of + * the double backslashes usually used in the UNC. This function + * gives us the latter, so we must adjust the result. + */ full_path = build_path_from_dentry(dentry); if (full_path == NULL) { rc = -ENOMEM; goto out_err; } - rc = get_dfs_path(xid, ses , full_path, cifs_sb->local_nls, + rc = get_dfs_path(xid, ses , full_path + 1, cifs_sb->local_nls, &num_referrals, &referrals, cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); @@ -310,7 +357,7 @@ cifs_dfs_follow_mountpoint(struct dentry *dentry, struct nameidata *nd) } mnt = cifs_dfs_do_refmount(nd->path.mnt, nd->path.dentry, - referrals[i].node_name); + referrals + i); cFYI(1, ("%s: cifs_dfs_do_refmount:%s , mnt:%p", __func__, referrals[i].node_name, mnt)); |