LXR linux/fs/ksmbd/smbacl.h

   1/* SPDX-License-Identifier: LGPL-2.1+ */
   2/*
   3 *   Copyright (c) International Business Machines  Corp., 2007
   4 *   Author(s): Steve French (sfrench@us.ibm.com)
   5 *   Modified by Namjae Jeon (linkinjeon@kernel.org)
   6 */
   7
   8#ifndef _SMBACL_H
   9#define _SMBACL_H
  10
  11#include <linux/fs.h>
  12#include <linux/namei.h>
  13#include <linux/posix_acl.h>
  14
  15#include "mgmt/tree_connect.h"
  16
  17#define NUM_AUTHS (6)   /* number of authority fields */
  18#define SID_MAX_SUB_AUTHORITIES (15) /* max number of sub authority fields */
  19
  20/*
  21 * ACE types - see MS-DTYP 2.4.4.1
  22 */
  23enum {
  24        ACCESS_ALLOWED,
  25        ACCESS_DENIED,
  26};
  27
  28/*
  29 * Security ID types
  30 */
  31enum {
  32        SIDOWNER = 1,
  33        SIDGROUP,
  34        SIDCREATOR_OWNER,
  35        SIDCREATOR_GROUP,
  36        SIDUNIX_USER,
  37        SIDUNIX_GROUP,
  38        SIDNFS_USER,
  39        SIDNFS_GROUP,
  40        SIDNFS_MODE,
  41};
  42
  43/* Revision for ACLs */
  44#define SD_REVISION     1
  45
  46/* Control flags for Security Descriptor */
  47#define OWNER_DEFAULTED         0x0001
  48#define GROUP_DEFAULTED         0x0002
  49#define DACL_PRESENT            0x0004
  50#define DACL_DEFAULTED          0x0008
  51#define SACL_PRESENT            0x0010
  52#define SACL_DEFAULTED          0x0020
  53#define DACL_TRUSTED            0x0040
  54#define SERVER_SECURITY         0x0080
  55#define DACL_AUTO_INHERIT_REQ   0x0100
  56#define SACL_AUTO_INHERIT_REQ   0x0200
  57#define DACL_AUTO_INHERITED     0x0400
  58#define SACL_AUTO_INHERITED     0x0800
  59#define DACL_PROTECTED          0x1000
  60#define SACL_PROTECTED          0x2000
  61#define RM_CONTROL_VALID        0x4000
  62#define SELF_RELATIVE           0x8000
  63
  64/* ACE types - see MS-DTYP 2.4.4.1 */
  65#define ACCESS_ALLOWED_ACE_TYPE 0x00
  66#define ACCESS_DENIED_ACE_TYPE  0x01
  67#define SYSTEM_AUDIT_ACE_TYPE   0x02
  68#define SYSTEM_ALARM_ACE_TYPE   0x03
  69#define ACCESS_ALLOWED_COMPOUND_ACE_TYPE 0x04
  70#define ACCESS_ALLOWED_OBJECT_ACE_TYPE  0x05
  71#define ACCESS_DENIED_OBJECT_ACE_TYPE   0x06
  72#define SYSTEM_AUDIT_OBJECT_ACE_TYPE    0x07
  73#define SYSTEM_ALARM_OBJECT_ACE_TYPE    0x08
  74#define ACCESS_ALLOWED_CALLBACK_ACE_TYPE 0x09
  75#define ACCESS_DENIED_CALLBACK_ACE_TYPE 0x0A
  76#define ACCESS_ALLOWED_CALLBACK_OBJECT_ACE_TYPE 0x0B
  77#define ACCESS_DENIED_CALLBACK_OBJECT_ACE_TYPE  0x0C
  78#define SYSTEM_AUDIT_CALLBACK_ACE_TYPE  0x0D
  79#define SYSTEM_ALARM_CALLBACK_ACE_TYPE  0x0E /* Reserved */
  80#define SYSTEM_AUDIT_CALLBACK_OBJECT_ACE_TYPE 0x0F
  81#define SYSTEM_ALARM_CALLBACK_OBJECT_ACE_TYPE 0x10 /* reserved */
  82#define SYSTEM_MANDATORY_LABEL_ACE_TYPE 0x11
  83#define SYSTEM_RESOURCE_ATTRIBUTE_ACE_TYPE 0x12
  84#define SYSTEM_SCOPED_POLICY_ID_ACE_TYPE 0x13
  85
  86/* ACE flags */
  87#define OBJECT_INHERIT_ACE              0x01
  88#define CONTAINER_INHERIT_ACE           0x02
  89#define NO_PROPAGATE_INHERIT_ACE        0x04
  90#define INHERIT_ONLY_ACE                0x08
  91#define INHERITED_ACE                   0x10
  92#define SUCCESSFUL_ACCESS_ACE_FLAG      0x40
  93#define FAILED_ACCESS_ACE_FLAG          0x80
  94
  95/*
  96 * Maximum size of a string representation of a SID:
  97 *
  98 * The fields are unsigned values in decimal. So:
  99 *
 100 * u8:  max 3 bytes in decimal
 101 * u32: max 10 bytes in decimal
 102 *
 103 * "S-" + 3 bytes for version field + 15 for authority field + NULL terminator
 104 *
 105 * For authority field, max is when all 6 values are non-zero and it must be
 106 * represented in hex. So "-0x" + 12 hex digits.
 107 *
 108 * Add 11 bytes for each subauthority field (10 bytes each + 1 for '-')
 109 */
 110#define SID_STRING_BASE_SIZE (2 + 3 + 15 + 1)
 111#define SID_STRING_SUBAUTH_SIZE (11) /* size of a single subauth string */
 112
 113#define DOMAIN_USER_RID_LE      cpu_to_le32(513)
 114
 115struct ksmbd_conn;
 116
 117struct smb_ntsd {
 118        __le16 revision; /* revision level */
 119        __le16 type;
 120        __le32 osidoffset;
 121        __le32 gsidoffset;
 122        __le32 sacloffset;
 123        __le32 dacloffset;
 124} __packed;
 125
 126struct smb_sid {
 127        __u8 revision; /* revision level */
 128        __u8 num_subauth;
 129        __u8 authority[NUM_AUTHS];
 130        __le32 sub_auth[SID_MAX_SUB_AUTHORITIES]; /* sub_auth[num_subauth] */
 131} __packed;
 132
 133/* size of a struct cifs_sid, sans sub_auth array */
 134#define CIFS_SID_BASE_SIZE (1 + 1 + NUM_AUTHS)
 135
 136struct smb_acl {
 137        __le16 revision; /* revision level */
 138        __le16 size;
 139        __le32 num_aces;
 140} __packed;
 141
 142struct smb_ace {
 143        __u8 type;
 144        __u8 flags;
 145        __le16 size;
 146        __le32 access_req;
 147        struct smb_sid sid; /* ie UUID of user or group who gets these perms */
 148} __packed;
 149
 150struct smb_fattr {
 151        kuid_t  cf_uid;
 152        kgid_t  cf_gid;
 153        umode_t cf_mode;
 154        __le32 daccess;
 155        struct posix_acl *cf_acls;
 156        struct posix_acl *cf_dacls;
 157};
 158
 159struct posix_ace_state {
 160        u32 allow;
 161        u32 deny;
 162};
 163
 164struct posix_user_ace_state {
 165        union {
 166                kuid_t uid;
 167                kgid_t gid;
 168        };
 169        struct posix_ace_state perms;
 170};
 171
 172struct posix_ace_state_array {
 173        int n;
 174        struct posix_user_ace_state aces[];
 175};
 176
 177/*
 178 * while processing the nfsv4 ace, this maintains the partial permissions
 179 * calculated so far:
 180 */
 181
 182struct posix_acl_state {
 183        struct posix_ace_state owner;
 184        struct posix_ace_state group;
 185        struct posix_ace_state other;
 186        struct posix_ace_state everyone;
 187        struct posix_ace_state mask; /* deny unused in this case */
 188        struct posix_ace_state_array *users;
 189        struct posix_ace_state_array *groups;
 190};
 191
 192int parse_sec_desc(struct user_namespace *user_ns, struct smb_ntsd *pntsd,
 193                   int acl_len, struct smb_fattr *fattr);
 194int build_sec_desc(struct user_namespace *user_ns, struct smb_ntsd *pntsd,
 195                   struct smb_ntsd *ppntsd, int addition_info,
 196                   __u32 *secdesclen, struct smb_fattr *fattr);
 197int init_acl_state(struct posix_acl_state *state, int cnt);
 198void free_acl_state(struct posix_acl_state *state);
 199void posix_state_to_acl(struct posix_acl_state *state,
 200                        struct posix_acl_entry *pace);
 201int compare_sids(const struct smb_sid *ctsid, const struct smb_sid *cwsid);
 202bool smb_inherit_flags(int flags, bool is_dir);
 203int smb_inherit_dacl(struct ksmbd_conn *conn, struct path *path,
 204                     unsigned int uid, unsigned int gid);
 205int smb_check_perm_dacl(struct ksmbd_conn *conn, struct path *path,
 206                        __le32 *pdaccess, int uid);
 207int set_info_sec(struct ksmbd_conn *conn, struct ksmbd_tree_connect *tcon,
 208                 struct path *path, struct smb_ntsd *pntsd, int ntsd_len,
 209                 bool type_check);
 210void id_to_sid(unsigned int cid, uint sidtype, struct smb_sid *ssid);
 211void ksmbd_init_domain(u32 *sub_auth);
 212
 213static inline uid_t posix_acl_uid_translate(struct user_namespace *mnt_userns,
 214                                            struct posix_acl_entry *pace)
 215{
 216        kuid_t kuid;
 217
 218        /* If this is an idmapped mount, apply the idmapping. */
 219        kuid = kuid_into_mnt(mnt_userns, pace->e_uid);
 220
 221        /* Translate the kuid into a userspace id ksmbd would see. */
 222        return from_kuid(&init_user_ns, kuid);
 223}
 224
 225static inline gid_t posix_acl_gid_translate(struct user_namespace *mnt_userns,
 226                                            struct posix_acl_entry *pace)
 227{
 228        kgid_t kgid;
 229
 230        /* If this is an idmapped mount, apply the idmapping. */
 231        kgid = kgid_into_mnt(mnt_userns, pace->e_gid);
 232
 233        /* Translate the kgid into a userspace id ksmbd would see. */
 234        return from_kgid(&init_user_ns, kgid);
 235}
 236
 237#endif /* _SMBACL_H */
 238