Use new helper in find_domain_name() and find_timestamp() to avoid
duplicating code.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@xxxxxxxxxxxxx>
---
fs/smb/client/cifsencrypt.c | 123 ++++++++++++++++--------------------
fs/smb/client/cifspdu.h | 2 +-
2 files changed, 54 insertions(+), 71 deletions(-)
diff --git a/fs/smb/client/cifsencrypt.c b/fs/smb/client/cifsencrypt.c
index 7a43daacc815..981897ec4dcd 100644
--- a/fs/smb/client/cifsencrypt.c
+++ b/fs/smb/client/cifsencrypt.c
@@ -315,6 +315,39 @@ build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
return 0;
}
+#define AV_TYPE(av) (le16_to_cpu(av->type))
+#define AV_LEN(av) (le16_to_cpu(av->length))
+#define AV_DATA_PTR(av) ((void *)av->data)
+
+#define av_for_each_entry(ses, av) \
+ for (av = NULL; (av = find_next_av(ses, av));)
+
+static struct ntlmssp2_name *find_next_av(struct cifs_ses *ses,
+ struct ntlmssp2_name *av)
+{
+ u16 len;
+ u8 *end;
+
+ end = (u8 *)ses->auth_key.response + ses->auth_key.len;
+ if (!av) {
+ if (unlikely(!ses->auth_key.response || !ses->auth_key.len))
+ return NULL;
+ av = (void *)ses->auth_key.response;
+ } else {
+ av = (void *)((u8 *)av + sizeof(*av) + AV_LEN(av));
+ }
+
+ if ((u8 *)av + sizeof(*av) > end)
+ return NULL;
+
+ len = AV_LEN(av);
+ if (AV_TYPE(av) == NTLMSSP_AV_EOL)
+ return NULL;
+ if (!len || (u8 *)av + sizeof(*av) + len > end)
+ return NULL;
+ return av;
+}
+
/* Server has provided av pairs/target info in the type 2 challenge
* packet and we have plucked it and stored within smb session.
* We parse that blob here to find netbios domain name to be used
@@ -325,49 +358,23 @@ build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
* may not fail against other (those who are not very particular
* about target string i.e. for some, just user name might suffice.
*/
-static int
-find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
+static int find_domain_name(struct cifs_ses *ses)
{
- unsigned int attrsize;
- unsigned int type;
- unsigned int onesize = sizeof(struct ntlmssp2_name);
- unsigned char *blobptr;
- unsigned char *blobend;
- struct ntlmssp2_name *attrptr;
+ const struct nls_table *nlsc = ses->local_nls;
+ struct ntlmssp2_name *av;
+ u16 len;
- if (!ses->auth_key.len || !ses->auth_key.response)
- return 0;
-
- blobptr = ses->auth_key.response;
- blobend = blobptr + ses->auth_key.len;
-
- while (blobptr + onesize < blobend) {
- attrptr = (struct ntlmssp2_name *) blobptr;
- type = le16_to_cpu(attrptr->type);
- if (type == NTLMSSP_AV_EOL)
- break;
- blobptr += 2; /* advance attr type */
- attrsize = le16_to_cpu(attrptr->length);
- blobptr += 2; /* advance attr size */
- if (blobptr + attrsize > blobend)
- break;
- if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
- if (!attrsize || attrsize >= CIFS_MAX_DOMAINNAME_LEN)
- break;
- if (!ses->domainName) {
- ses->domainName =
- kmalloc(attrsize + 1, GFP_KERNEL);
- if (!ses->domainName)
- return -ENOMEM;
- cifs_from_utf16(ses->domainName,
- (__le16 *)blobptr, attrsize, attrsize,
- nls_cp, NO_MAP_UNI_RSVD);
- break;
- }
+ av_for_each_entry(ses, av) {
+ len = AV_LEN(av);
+ if (AV_TYPE(av) == NTLMSSP_AV_NB_DOMAIN_NAME &&
+ len < CIFS_MAX_DOMAINNAME_LEN && !ses->domainName) {
+ ses->domainName = kmalloc(len + 1, GFP_KERNEL);
+ if (!ses->domainName)
+ return -ENOMEM;
+ cifs_from_utf16(ses->domainName, AV_DATA_PTR(av),
+ len, len, nlsc, NO_MAP_UNI_RSVD);
}
- blobptr += attrsize; /* advance attr value */
}
-
return 0;
}
@@ -377,40 +384,16 @@ find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
* as part of ntlmv2 authentication (or local current time as
* default in case of failure)
*/
-static __le64
-find_timestamp(struct cifs_ses *ses)
+static __le64 find_timestamp(struct cifs_ses *ses)
{
- unsigned int attrsize;
- unsigned int type;
- unsigned int onesize = sizeof(struct ntlmssp2_name);
- unsigned char *blobptr;
- unsigned char *blobend;
- struct ntlmssp2_name *attrptr;
+ struct ntlmssp2_name *av;
struct timespec64 ts;
- if (!ses->auth_key.len || !ses->auth_key.response)
- return 0;
-
- blobptr = ses->auth_key.response;
- blobend = blobptr + ses->auth_key.len;
-
- while (blobptr + onesize < blobend) {
- attrptr = (struct ntlmssp2_name *) blobptr;
- type = le16_to_cpu(attrptr->type);
- if (type == NTLMSSP_AV_EOL)
- break;
- blobptr += 2; /* advance attr type */
- attrsize = le16_to_cpu(attrptr->length);
- blobptr += 2; /* advance attr size */
- if (blobptr + attrsize > blobend)
- break;
- if (type == NTLMSSP_AV_TIMESTAMP) {
- if (attrsize == sizeof(u64))
- return *((__le64 *)blobptr);
- }
- blobptr += attrsize; /* advance attr value */
+ av_for_each_entry(ses, av) {
+ if (AV_TYPE(av) == NTLMSSP_AV_TIMESTAMP &&
+ AV_LEN(av) == sizeof(u64))
+ return *((__le64 *)AV_DATA_PTR(av));
}
-
ktime_get_real_ts64(&ts);
return cpu_to_le64(cifs_UnixTimeToNT(ts));
}
@@ -563,7 +546,7 @@ setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED) {
if (!ses->domainName) {
if (ses->domainAuto) {
- rc = find_domain_name(ses, nls_cp);
+ rc = find_domain_name(ses);
if (rc) {
cifs_dbg(VFS, "error %d finding domain name\n",
rc);
diff --git a/fs/smb/client/cifspdu.h b/fs/smb/client/cifspdu.h
index ee78bb6741d6..17202754e6d0 100644
--- a/fs/smb/client/cifspdu.h
+++ b/fs/smb/client/cifspdu.h
@@ -649,7 +649,7 @@ typedef union smb_com_session_setup_andx {
struct ntlmssp2_name {
__le16 type;
__le16 length;
-/* char name[length]; */
+ __u8 data[];
} __attribute__((packed));
struct ntlmv2_resp {
--
2.47.1
