diff options
author | Stefan Metzmacher <metze@samba.org> | 2010-07-31 09:14:16 +0200 |
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committer | Steve French <sfrench@us.ibm.com> | 2010-09-29 19:04:30 +0000 |
commit | c69c1b6eaea1b3e1eecf7ad2fba0208ac4a11131 (patch) | |
tree | ad267df56902eaaf89afd9bb2431ce6cff3ea2af | |
parent | 3eb9a8893a76cf1cda3b41c3212eb2cfe83eae0e (diff) |
cifs: implement CIFSParseMFSymlink()
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
-rw-r--r-- | fs/cifs/link.c | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/fs/cifs/link.c b/fs/cifs/link.c index 473ca803365..12eb491d4c5 100644 --- a/fs/cifs/link.c +++ b/fs/cifs/link.c @@ -28,6 +28,68 @@ #include "cifsproto.h" #include "cifs_debug.h" #include "cifs_fs_sb.h" +#include "md5.h" + +#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 \ + "%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n" +#define CIFS_MF_SYMLINK_MD5_ARGS(md5_hash) \ + md5_hash[0], md5_hash[1], md5_hash[2], md5_hash[3], \ + md5_hash[4], md5_hash[5], md5_hash[6], md5_hash[7], \ + md5_hash[8], md5_hash[9], md5_hash[10], md5_hash[11],\ + md5_hash[12], md5_hash[13], md5_hash[14], md5_hash[15] + +static int +CIFSParseMFSymlink(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; + struct MD5Context md5_ctx; + 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; + + cifs_MD5_init(&md5_ctx); + cifs_MD5_update(&md5_ctx, (const u8 *)link_str, link_len); + cifs_MD5_final(md5_hash, &md5_ctx); + + snprintf(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; +} int cifs_hardlink(struct dentry *old_file, struct inode *inode, |