[CIFS] Support for CIFS ACLs (part 1)

Add code to be able to dump CIFS ACL information
when Query Posix ACL with cifsacl mount parm enabled.
Signed-off-by: Shirish Pargoankar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

fs/cifs/cifsacl.h

@@ -22,12 +22,42 @@
 #ifndef _CIFSACL_H
 #define _CIFSACL_H
 
+struct cifs_ntsd {
+	__u16 revision; /* revision level */
+	__u16 type;
+	__u32 osidoffset;
+	__u32 gsidoffset;
+	__u32 sacloffset;
+	__u32 dacloffset;
+} __attribute__((packed));
+
 struct cifs_sid {
 	__u8 revision; /* revision level */
-	__u8 num_subauths;
+	__u8 num_auth;
+	__u8 authority[6];
+	__u32 sub_auth[4];
+	__u32 rid;
+} __attribute__((packed));
+
+struct cifs_acl {
+	__u16 revision; /* revision level */
+	__u16 size;
+	__u32 num_aces;
+} __attribute__((packed));
+
+struct cifs_ntace {
+	__u8 type;
+	__u8 flags;
+	__u16 size;
+	__u32 access_req;
+} __attribute__((packed));
+
+struct cifs_ace {
+	__u8 revision; /* revision level */
+	__u8 num_auth;
 	__u8 authority[6];
 	__u32 sub_auth[4];
-	/* next sub_auth if any ... */
+	__u32 rid;
 } __attribute__((packed));
 
 /* everyone */

fs/cifs/cifsglob.h

@@ -19,6 +19,7 @@
 #include <linux/in.h>
 #include <linux/in6.h>
 #include "cifs_fs_sb.h"
+#include "cifsacl.h"
 /*
  * The sizes of various internal tables and strings
  */
@@ -115,6 +116,17 @@ struct mac_key {
 	} data;
 };
 
+struct cifs_cred {
+	int uid;
+	int gid;
+	int mode;
+	int cecount;
+	struct cifs_sid osid;
+	struct cifs_sid gsid;
+	struct cifs_ntace *ntaces;
+	struct cifs_ace *aces;
+};
+
 /*
  *****************************************************************
  * Except the CIFS PDUs themselves all the

fs/cifs/cifssmb.c

@@ -3048,17 +3048,110 @@ static const struct cifs_sid sid_everyone =
 static const struct cifs_sid sid_user =
 		{1, 2 , {0, 0, 0, 0, 0, 5}, {32, 545, 0, 0}};
 
+static void parse_sid(struct cifs_sid * psid, char * end_of_acl)
+{
+	/* BB need to add parm so we can store the SID BB */
+
+	/* validate that we do not go past end of acl */
+	if (end_of_acl < (char *)psid + sizeof(struct cifs_sid)) {
+		cERROR(1, ("ACL to small to parse SID"));
+		return;
+	}
+#ifdef CONFIG_CIFS_DEBUG2
+	cFYI(1, ("revision %d num_auth %d First subauth 0x%x",
+		psid->revision, psid->num_auth, psid->sub_auth[0]));
+
+	/* BB add length check to make sure that we do not have huge num auths
+	      and therefore go off the end */
+	cFYI(1, ("RID 0x%x", le32_to_cpu(psid->sub_auth[psid->num_auth])));
+#endif
+	return;
+}
+
 /* Convert CIFS ACL to POSIX form */
-static int parse_sec_desc(struct cifs_sid *psec_desc, int acl_len)
+static int parse_sec_desc(struct cifs_ntsd *pntsd, int acl_len)
 {
-	return 0;
+	int i;
+	int num_aces = 0;
+	int acl_size;
+	struct cifs_sid *owner_sid_ptr, *group_sid_ptr;
+	struct cifs_acl *dacl_ptr; /* no need for SACL ptr */
+	struct cifs_ntace **ppntace;
+	struct cifs_ace **ppace;
+	char *acl_base;
+	char *end_of_acl = ((char *)pntsd) + acl_len;
+
+	owner_sid_ptr = (struct cifs_sid *)((char *)pntsd +
+				cpu_to_le32(pntsd->osidoffset));
+	group_sid_ptr = (struct cifs_sid *)((char *)pntsd +
+				cpu_to_le32(pntsd->gsidoffset));
+	dacl_ptr = (struct cifs_acl *)((char *)pntsd +
+				cpu_to_le32(pntsd->dacloffset));
+#ifdef CONFIG_CIFS_DEBUG2
+	cFYI(1,("revision %d type 0x%x ooffset 0x%x goffset 0x%x "
+		"sacloffset 0x%x dacloffset 0x%x", pntsd->revision, pntsd->type,
+		pntsd->osidoffset, pntsd->gsidoffset, pntsd->sacloffset,
+		pntsd->dacloffset));
+#endif
+	parse_sid(owner_sid_ptr, end_of_acl);
+	parse_sid(group_sid_ptr, end_of_acl);
+
+/*	cifscred->uid = owner_sid_ptr->rid;
+	cifscred->gid = group_sid_ptr->rid;
+	memcpy((void *)(&(cifscred->osid)), (void *)owner_sid_ptr,
+			sizeof (struct cifs_sid));
+	memcpy((void *)(&(cifscred->gsid)), (void *)group_sid_ptr,
+			sizeof (struct cifs_sid)); */
+
+	num_aces = cpu_to_le32(dacl_ptr->num_aces);
+	cFYI(1, ("num aces %d", num_aces));
+	if (num_aces  > 0) {
+		ppntace = kmalloc(num_aces * sizeof(struct cifs_ntace *),
+				GFP_KERNEL);
+		ppace = kmalloc(num_aces * sizeof(struct cifs_ace *),
+				GFP_KERNEL);
+
+/*		cifscred->cecount = dacl_ptr->num_aces;
+		cifscred->ntaces = kmalloc(num_aces *
+				sizeof(struct cifs_ntace *), GFP_KERNEL);
+		cifscred->aces = kmalloc(num_aces *
+				sizeof(struct cifs_ace *), GFP_KERNEL);*/
+
+		acl_base = (char *)dacl_ptr;
+		acl_size = sizeof(struct cifs_acl);
+
+		for (i = 0; i < num_aces; ++i) {
+			ppntace[i] = (struct cifs_ntace *)
+						(acl_base + acl_size);
+			ppace[i] = (struct cifs_ace *)
+					((char *)ppntace[i] +
+					sizeof(struct cifs_ntace));
+
+/*			memcpy((void *)(&(cifscred->ntaces[i])),
+				(void *)ntace_ptrptr[i],
+				sizeof(struct cifs_ntace));
+			memcpy((void *)(&(cifscred->aces[i])),
+				(void *)ace_ptrptr[i],
+				sizeof(struct cifs_ace)); */
+
+			acl_base = (char *)ppntace[i];
+			acl_size = cpu_to_le32(ppntace[i]->size);
+#ifdef CONFIG_CIFS_DEBUG2
+			cFYI(1, ("ACE revision:%d", ppace[i]->revision));
+		}
+#endif
+		kfree(ppace);
+		kfree(ppntace);
+	}
+
+	return (0);
 }
 
 /* Get Security Descriptor (by handle) from remote server for a file or dir */
 int
 CIFSSMBGetCIFSACL(const int xid, struct cifsTconInfo *tcon, __u16 fid,
 		/* BB fix up return info */ char *acl_inf, const int buflen,
-		  const int acl_type /* ACCESS/DEFAULT not sure implication */)
+		  const int acl_type)
 {
 	int rc = 0;
 	int buf_type = 0;
@@ -3088,7 +3181,7 @@ CIFSSMBGetCIFSACL(const int xid, struct cifsTconInfo *tcon, __u16 fid,
 	if (rc) {
 		cFYI(1, ("Send error in QuerySecDesc = %d", rc));
 	} else {                /* decode response */
-		struct cifs_sid *psec_desc;
+		struct cifs_ntsd *psec_desc;
 		__le32 * parm;
 		int parm_len;
 		int data_len;

fs/cifs/connect.c

@@ -1742,9 +1742,9 @@ void reset_cifs_unix_caps(int xid, struct cifsTconInfo *tcon,
 			cFYI(1, ("very large write cap"));
 #endif /* CIFS_DEBUG2 */
 		if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
-			if (vol_info == NULL)
+			if (vol_info == NULL) {
 				cFYI(1, ("resetting capabilities failed"));
-			else
+			} else
 				cERROR(1, ("Negotiating Unix capabilities "
 					   "with the server failed.  Consider "
 					   "mounting with the Unix Extensions\n"