From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- fs/smb/client/link.c | 650 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 650 insertions(+) create mode 100644 fs/smb/client/link.c (limited to 'fs/smb/client/link.c') diff --git a/fs/smb/client/link.c b/fs/smb/client/link.c new file mode 100644 index 0000000000..c66be4904e --- /dev/null +++ b/fs/smb/client/link.c @@ -0,0 +1,650 @@ +// SPDX-License-Identifier: LGPL-2.1 +/* + * + * Copyright (C) International Business Machines Corp., 2002,2008 + * Author(s): Steve French (sfrench@us.ibm.com) + * + */ +#include +#include +#include +#include +#include "cifsfs.h" +#include "cifspdu.h" +#include "cifsglob.h" +#include "cifsproto.h" +#include "cifs_debug.h" +#include "cifs_fs_sb.h" +#include "cifs_unicode.h" +#include "smb2proto.h" +#include "cifs_ioctl.h" + +/* + * M-F Symlink Functions - Begin + */ + +#define CIFS_MF_SYMLINK_LEN_OFFSET (4+1) +#define CIFS_MF_SYMLINK_MD5_OFFSET (CIFS_MF_SYMLINK_LEN_OFFSET+(4+1)) +#define CIFS_MF_SYMLINK_LINK_OFFSET (CIFS_MF_SYMLINK_MD5_OFFSET+(32+1)) +#define CIFS_MF_SYMLINK_LINK_MAXLEN (1024) +#define CIFS_MF_SYMLINK_FILE_SIZE \ + (CIFS_MF_SYMLINK_LINK_OFFSET + CIFS_MF_SYMLINK_LINK_MAXLEN) + +#define CIFS_MF_SYMLINK_LEN_FORMAT "XSym\n%04u\n" +#define CIFS_MF_SYMLINK_MD5_FORMAT "%16phN\n" +#define CIFS_MF_SYMLINK_MD5_ARGS(md5_hash) md5_hash + +static int +symlink_hash(unsigned int link_len, const char *link_str, u8 *md5_hash) +{ + int rc; + struct shash_desc *md5 = NULL; + + rc = cifs_alloc_hash("md5", &md5); + if (rc) + goto symlink_hash_err; + + rc = crypto_shash_init(md5); + if (rc) { + cifs_dbg(VFS, "%s: Could not init md5 shash\n", __func__); + goto symlink_hash_err; + } + rc = crypto_shash_update(md5, link_str, link_len); + if (rc) { + cifs_dbg(VFS, "%s: Could not update with link_str\n", __func__); + goto symlink_hash_err; + } + rc = crypto_shash_final(md5, md5_hash); + if (rc) + cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__); + +symlink_hash_err: + cifs_free_hash(&md5); + return rc; +} + +static int +parse_mf_symlink(const u8 *buf, unsigned int buf_len, unsigned int *_link_len, + char **_link_str) +{ + int rc; + unsigned int link_len; + const char *md5_str1; + const char *link_str; + u8 md5_hash[16]; + char md5_str2[34]; + + if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE) + return -EINVAL; + + md5_str1 = (const char *)&buf[CIFS_MF_SYMLINK_MD5_OFFSET]; + link_str = (const char *)&buf[CIFS_MF_SYMLINK_LINK_OFFSET]; + + rc = sscanf(buf, CIFS_MF_SYMLINK_LEN_FORMAT, &link_len); + if (rc != 1) + return -EINVAL; + + if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN) + return -EINVAL; + + rc = symlink_hash(link_len, link_str, md5_hash); + if (rc) { + cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc); + return rc; + } + + scnprintf(md5_str2, sizeof(md5_str2), + CIFS_MF_SYMLINK_MD5_FORMAT, + CIFS_MF_SYMLINK_MD5_ARGS(md5_hash)); + + if (strncmp(md5_str1, md5_str2, 17) != 0) + return -EINVAL; + + if (_link_str) { + *_link_str = kstrndup(link_str, link_len, GFP_KERNEL); + if (!*_link_str) + return -ENOMEM; + } + + *_link_len = link_len; + return 0; +} + +static int +format_mf_symlink(u8 *buf, unsigned int buf_len, const char *link_str) +{ + int rc; + unsigned int link_len; + unsigned int ofs; + u8 md5_hash[16]; + + if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE) + return -EINVAL; + + link_len = strlen(link_str); + + if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN) + return -ENAMETOOLONG; + + rc = symlink_hash(link_len, link_str, md5_hash); + if (rc) { + cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc); + return rc; + } + + scnprintf(buf, buf_len, + CIFS_MF_SYMLINK_LEN_FORMAT CIFS_MF_SYMLINK_MD5_FORMAT, + link_len, + CIFS_MF_SYMLINK_MD5_ARGS(md5_hash)); + + ofs = CIFS_MF_SYMLINK_LINK_OFFSET; + memcpy(buf + ofs, link_str, link_len); + + ofs += link_len; + if (ofs < CIFS_MF_SYMLINK_FILE_SIZE) { + buf[ofs] = '\n'; + ofs++; + } + + while (ofs < CIFS_MF_SYMLINK_FILE_SIZE) { + buf[ofs] = ' '; + ofs++; + } + + return 0; +} + +bool +couldbe_mf_symlink(const struct cifs_fattr *fattr) +{ + if (!S_ISREG(fattr->cf_mode)) + /* it's not a symlink */ + return false; + + if (fattr->cf_eof != CIFS_MF_SYMLINK_FILE_SIZE) + /* it's not a symlink */ + return false; + + return true; +} + +static int +create_mf_symlink(const unsigned int xid, struct cifs_tcon *tcon, + struct cifs_sb_info *cifs_sb, const char *fromName, + const char *toName) +{ + int rc; + u8 *buf; + unsigned int bytes_written = 0; + + buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + rc = format_mf_symlink(buf, CIFS_MF_SYMLINK_FILE_SIZE, toName); + if (rc) + goto out; + + if (tcon->ses->server->ops->create_mf_symlink) + rc = tcon->ses->server->ops->create_mf_symlink(xid, tcon, + cifs_sb, fromName, buf, &bytes_written); + else + rc = -EOPNOTSUPP; + + if (rc) + goto out; + + if (bytes_written != CIFS_MF_SYMLINK_FILE_SIZE) + rc = -EIO; +out: + kfree(buf); + return rc; +} + +int +check_mf_symlink(unsigned int xid, struct cifs_tcon *tcon, + struct cifs_sb_info *cifs_sb, struct cifs_fattr *fattr, + const unsigned char *path) +{ + int rc; + u8 *buf = NULL; + unsigned int link_len = 0; + unsigned int bytes_read = 0; + char *symlink = NULL; + + if (!couldbe_mf_symlink(fattr)) + /* it's not a symlink */ + return 0; + + buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + if (tcon->ses->server->ops->query_mf_symlink) + rc = tcon->ses->server->ops->query_mf_symlink(xid, tcon, + cifs_sb, path, buf, &bytes_read); + else + rc = -ENOSYS; + + if (rc) + goto out; + + if (bytes_read == 0) /* not a symlink */ + goto out; + + rc = parse_mf_symlink(buf, bytes_read, &link_len, &symlink); + if (rc == -EINVAL) { + /* it's not a symlink */ + rc = 0; + goto out; + } + + if (rc != 0) + goto out; + + /* it is a symlink */ + fattr->cf_eof = link_len; + fattr->cf_mode &= ~S_IFMT; + fattr->cf_mode |= S_IFLNK | S_IRWXU | S_IRWXG | S_IRWXO; + fattr->cf_dtype = DT_LNK; + fattr->cf_symlink_target = symlink; +out: + kfree(buf); + return rc; +} + +#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY +/* + * SMB 1.0 Protocol specific functions + */ + +int +cifs_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon, + struct cifs_sb_info *cifs_sb, const unsigned char *path, + char *pbuf, unsigned int *pbytes_read) +{ + int rc; + int oplock = 0; + struct cifs_fid fid; + struct cifs_open_parms oparms; + struct cifs_io_parms io_parms = {0}; + int buf_type = CIFS_NO_BUFFER; + FILE_ALL_INFO file_info; + + oparms = (struct cifs_open_parms) { + .tcon = tcon, + .cifs_sb = cifs_sb, + .desired_access = GENERIC_READ, + .create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR), + .disposition = FILE_OPEN, + .path = path, + .fid = &fid, + }; + + rc = CIFS_open(xid, &oparms, &oplock, &file_info); + if (rc) + return rc; + + if (file_info.EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) { + rc = -ENOENT; + /* it's not a symlink */ + goto out; + } + + io_parms.netfid = fid.netfid; + io_parms.pid = current->tgid; + io_parms.tcon = tcon; + io_parms.offset = 0; + io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE; + + rc = CIFSSMBRead(xid, &io_parms, pbytes_read, &pbuf, &buf_type); +out: + CIFSSMBClose(xid, tcon, fid.netfid); + return rc; +} + +int +cifs_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon, + struct cifs_sb_info *cifs_sb, const unsigned char *path, + char *pbuf, unsigned int *pbytes_written) +{ + int rc; + int oplock = 0; + struct cifs_fid fid; + struct cifs_open_parms oparms; + struct cifs_io_parms io_parms = {0}; + + oparms = (struct cifs_open_parms) { + .tcon = tcon, + .cifs_sb = cifs_sb, + .desired_access = GENERIC_WRITE, + .create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR), + .disposition = FILE_CREATE, + .path = path, + .fid = &fid, + }; + + rc = CIFS_open(xid, &oparms, &oplock, NULL); + if (rc) + return rc; + + io_parms.netfid = fid.netfid; + io_parms.pid = current->tgid; + io_parms.tcon = tcon; + io_parms.offset = 0; + io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE; + + rc = CIFSSMBWrite(xid, &io_parms, pbytes_written, pbuf); + CIFSSMBClose(xid, tcon, fid.netfid); + return rc; +} +#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */ + +/* + * SMB 2.1/SMB3 Protocol specific functions + */ +int +smb3_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon, + struct cifs_sb_info *cifs_sb, const unsigned char *path, + char *pbuf, unsigned int *pbytes_read) +{ + int rc; + struct cifs_fid fid; + struct cifs_open_parms oparms; + struct cifs_io_parms io_parms = {0}; + int buf_type = CIFS_NO_BUFFER; + __le16 *utf16_path; + __u8 oplock = SMB2_OPLOCK_LEVEL_NONE; + struct smb2_file_all_info *pfile_info = NULL; + + oparms = (struct cifs_open_parms) { + .tcon = tcon, + .cifs_sb = cifs_sb, + .path = path, + .desired_access = GENERIC_READ, + .create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR), + .disposition = FILE_OPEN, + .fid = &fid, + }; + + utf16_path = cifs_convert_path_to_utf16(path, cifs_sb); + if (utf16_path == NULL) + return -ENOMEM; + + pfile_info = kzalloc(sizeof(struct smb2_file_all_info) + PATH_MAX * 2, + GFP_KERNEL); + + if (pfile_info == NULL) { + kfree(utf16_path); + return -ENOMEM; + } + + rc = SMB2_open(xid, &oparms, utf16_path, &oplock, pfile_info, NULL, + NULL, NULL); + if (rc) + goto qmf_out_open_fail; + + if (pfile_info->EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) { + /* it's not a symlink */ + rc = -ENOENT; /* Is there a better rc to return? */ + goto qmf_out; + } + + io_parms.netfid = fid.netfid; + io_parms.pid = current->tgid; + io_parms.tcon = tcon; + io_parms.offset = 0; + io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE; + io_parms.persistent_fid = fid.persistent_fid; + io_parms.volatile_fid = fid.volatile_fid; + rc = SMB2_read(xid, &io_parms, pbytes_read, &pbuf, &buf_type); +qmf_out: + SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid); +qmf_out_open_fail: + kfree(utf16_path); + kfree(pfile_info); + return rc; +} + +int +smb3_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon, + struct cifs_sb_info *cifs_sb, const unsigned char *path, + char *pbuf, unsigned int *pbytes_written) +{ + int rc; + struct cifs_fid fid; + struct cifs_open_parms oparms; + struct cifs_io_parms io_parms = {0}; + __le16 *utf16_path; + __u8 oplock = SMB2_OPLOCK_LEVEL_NONE; + struct kvec iov[2]; + + cifs_dbg(FYI, "%s: path: %s\n", __func__, path); + + utf16_path = cifs_convert_path_to_utf16(path, cifs_sb); + if (!utf16_path) + return -ENOMEM; + + oparms = (struct cifs_open_parms) { + .tcon = tcon, + .cifs_sb = cifs_sb, + .path = path, + .desired_access = GENERIC_WRITE, + .create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR), + .disposition = FILE_CREATE, + .fid = &fid, + .mode = 0644, + }; + + rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, NULL, + NULL, NULL); + if (rc) { + kfree(utf16_path); + return rc; + } + + io_parms.netfid = fid.netfid; + io_parms.pid = current->tgid; + io_parms.tcon = tcon; + io_parms.offset = 0; + io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE; + io_parms.persistent_fid = fid.persistent_fid; + io_parms.volatile_fid = fid.volatile_fid; + + /* iov[0] is reserved for smb header */ + iov[1].iov_base = pbuf; + iov[1].iov_len = CIFS_MF_SYMLINK_FILE_SIZE; + + rc = SMB2_write(xid, &io_parms, pbytes_written, iov, 1); + + /* Make sure we wrote all of the symlink data */ + if ((rc == 0) && (*pbytes_written != CIFS_MF_SYMLINK_FILE_SIZE)) + rc = -EIO; + + SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid); + + kfree(utf16_path); + return rc; +} + +/* + * M-F Symlink Functions - End + */ + +int +cifs_hardlink(struct dentry *old_file, struct inode *inode, + struct dentry *direntry) +{ + int rc = -EACCES; + unsigned int xid; + const char *from_name, *to_name; + void *page1, *page2; + struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb); + struct tcon_link *tlink; + struct cifs_tcon *tcon; + struct TCP_Server_Info *server; + struct cifsInodeInfo *cifsInode; + + if (unlikely(cifs_forced_shutdown(cifs_sb))) + return -EIO; + + tlink = cifs_sb_tlink(cifs_sb); + if (IS_ERR(tlink)) + return PTR_ERR(tlink); + tcon = tlink_tcon(tlink); + + xid = get_xid(); + page1 = alloc_dentry_path(); + page2 = alloc_dentry_path(); + + from_name = build_path_from_dentry(old_file, page1); + if (IS_ERR(from_name)) { + rc = PTR_ERR(from_name); + goto cifs_hl_exit; + } + to_name = build_path_from_dentry(direntry, page2); + if (IS_ERR(to_name)) { + rc = PTR_ERR(to_name); + goto cifs_hl_exit; + } + +#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY + if (tcon->unix_ext) + rc = CIFSUnixCreateHardLink(xid, tcon, from_name, to_name, + cifs_sb->local_nls, + cifs_remap(cifs_sb)); + else { +#else + { +#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */ + server = tcon->ses->server; + if (!server->ops->create_hardlink) { + rc = -ENOSYS; + goto cifs_hl_exit; + } + rc = server->ops->create_hardlink(xid, tcon, from_name, to_name, + cifs_sb); + if ((rc == -EIO) || (rc == -EINVAL)) + rc = -EOPNOTSUPP; + } + + d_drop(direntry); /* force new lookup from server of target */ + + /* + * if source file is cached (oplocked) revalidate will not go to server + * until the file is closed or oplock broken so update nlinks locally + */ + if (d_really_is_positive(old_file)) { + cifsInode = CIFS_I(d_inode(old_file)); + if (rc == 0) { + spin_lock(&d_inode(old_file)->i_lock); + inc_nlink(d_inode(old_file)); + spin_unlock(&d_inode(old_file)->i_lock); + + /* + * parent dir timestamps will update from srv within a + * second, would it really be worth it to set the parent + * dir cifs inode time to zero to force revalidate + * (faster) for it too? + */ + } + /* + * if not oplocked will force revalidate to get info on source + * file from srv. Note Samba server prior to 4.2 has bug - + * not updating src file ctime on hardlinks but Windows servers + * handle it properly + */ + cifsInode->time = 0; + + /* + * Will update parent dir timestamps from srv within a second. + * Would it really be worth it to set the parent dir (cifs + * inode) time field to zero to force revalidate on parent + * directory faster ie + * + * CIFS_I(inode)->time = 0; + */ + } + +cifs_hl_exit: + free_dentry_path(page1); + free_dentry_path(page2); + free_xid(xid); + cifs_put_tlink(tlink); + return rc; +} + +int +cifs_symlink(struct mnt_idmap *idmap, struct inode *inode, + struct dentry *direntry, const char *symname) +{ + int rc = -EOPNOTSUPP; + unsigned int xid; + struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb); + struct tcon_link *tlink; + struct cifs_tcon *pTcon; + const char *full_path; + void *page; + struct inode *newinode = NULL; + + if (unlikely(cifs_forced_shutdown(cifs_sb))) + return -EIO; + + page = alloc_dentry_path(); + if (!page) + return -ENOMEM; + + xid = get_xid(); + + tlink = cifs_sb_tlink(cifs_sb); + if (IS_ERR(tlink)) { + rc = PTR_ERR(tlink); + goto symlink_exit; + } + pTcon = tlink_tcon(tlink); + + full_path = build_path_from_dentry(direntry, page); + if (IS_ERR(full_path)) { + rc = PTR_ERR(full_path); + goto symlink_exit; + } + + cifs_dbg(FYI, "Full path: %s\n", full_path); + cifs_dbg(FYI, "symname is %s\n", symname); + + /* BB what if DFS and this volume is on different share? BB */ + if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) + rc = create_mf_symlink(xid, pTcon, cifs_sb, full_path, symname); +#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY + else if (pTcon->unix_ext) + rc = CIFSUnixCreateSymLink(xid, pTcon, full_path, symname, + cifs_sb->local_nls, + cifs_remap(cifs_sb)); +#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */ + /* else + rc = CIFSCreateReparseSymLink(xid, pTcon, fromName, toName, + cifs_sb_target->local_nls); */ + + if (rc == 0) { + if (pTcon->posix_extensions) + rc = smb311_posix_get_inode_info(&newinode, full_path, inode->i_sb, xid); + else if (pTcon->unix_ext) + rc = cifs_get_inode_info_unix(&newinode, full_path, + inode->i_sb, xid); + else + rc = cifs_get_inode_info(&newinode, full_path, NULL, + inode->i_sb, xid, NULL); + + if (rc != 0) { + cifs_dbg(FYI, "Create symlink ok, getinodeinfo fail rc = %d\n", + rc); + } else { + d_instantiate(direntry, newinode); + } + } +symlink_exit: + free_dentry_path(page); + cifs_put_tlink(tlink); + free_xid(xid); + return rc; +} -- cgit v1.2.3