security/integrity/integrity.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (C) 2009-2010 IBM Corporation
   4  *
   5  * Authors:
   6  * Mimi Zohar <zohar@us.ibm.com>
   7  */
   8
   9 #include <linux/types.h>
  10 #include <linux/integrity.h>
  11 #include <crypto/sha.h>
  12 #include <linux/key.h>
  13 #include <linux/audit.h>
  14
  15 /* iint action cache flags */
  16 #define IMA_MEASURE             0x00000001
  17 #define IMA_MEASURED            0x00000002
  18 #define IMA_APPRAISE            0x00000004
  19 #define IMA_APPRAISED           0x00000008
  20 /*#define IMA_COLLECT           0x00000010  do not use this flag */
  21 #define IMA_COLLECTED           0x00000020
  22 #define IMA_AUDIT               0x00000040
  23 #define IMA_AUDITED             0x00000080
  24 #define IMA_HASH                0x00000100
  25 #define IMA_HASHED              0x00000200
  26
  27 /* iint cache flags */
  28 #define IMA_ACTION_FLAGS        0xff000000
  29 #define IMA_DIGSIG_REQUIRED     0x01000000
  30 #define IMA_PERMIT_DIRECTIO     0x02000000
  31 #define IMA_NEW_FILE            0x04000000
  32 #define EVM_IMMUTABLE_DIGSIG    0x08000000
  33 #define IMA_FAIL_UNVERIFIABLE_SIGS      0x10000000
  34
  35 #define IMA_DO_MASK             (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
  36                                  IMA_HASH | IMA_APPRAISE_SUBMASK)
  37 #define IMA_DONE_MASK           (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \
  38                                  IMA_HASHED | IMA_COLLECTED | \
  39                                  IMA_APPRAISED_SUBMASK)
  40
  41 /* iint subaction appraise cache flags */
  42 #define IMA_FILE_APPRAISE       0x00001000
  43 #define IMA_FILE_APPRAISED      0x00002000
  44 #define IMA_MMAP_APPRAISE       0x00004000
  45 #define IMA_MMAP_APPRAISED      0x00008000
  46 #define IMA_BPRM_APPRAISE       0x00010000
  47 #define IMA_BPRM_APPRAISED      0x00020000
  48 #define IMA_READ_APPRAISE       0x00040000
  49 #define IMA_READ_APPRAISED      0x00080000
  50 #define IMA_CREDS_APPRAISE      0x00100000
  51 #define IMA_CREDS_APPRAISED     0x00200000
  52 #define IMA_APPRAISE_SUBMASK    (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \
  53                                  IMA_BPRM_APPRAISE | IMA_READ_APPRAISE | \
  54                                  IMA_CREDS_APPRAISE)
  55 #define IMA_APPRAISED_SUBMASK   (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
  56                                  IMA_BPRM_APPRAISED | IMA_READ_APPRAISED | \
  57                                  IMA_CREDS_APPRAISED)
  58
  59 /* iint cache atomic_flags */
  60 #define IMA_CHANGE_XATTR        0
  61 #define IMA_UPDATE_XATTR        1
  62 #define IMA_CHANGE_ATTR         2
  63 #define IMA_DIGSIG              3
  64 #define IMA_MUST_MEASURE        4
  65
  66 enum evm_ima_xattr_type {
  67         IMA_XATTR_DIGEST = 0x01,
  68         EVM_XATTR_HMAC,
  69         EVM_IMA_XATTR_DIGSIG,
  70         IMA_XATTR_DIGEST_NG,
  71         EVM_XATTR_PORTABLE_DIGSIG,
  72         IMA_XATTR_LAST
  73 };
  74
  75 struct evm_ima_xattr_data {
  76         u8 type;
  77         u8 data[];
  78 } __packed;
  79
  80 /* Only used in the EVM HMAC code. */
  81 struct evm_xattr {
  82         struct evm_ima_xattr_data data;
  83         u8 digest[SHA1_DIGEST_SIZE];
  84 } __packed;
  85
  86 #define IMA_MAX_DIGEST_SIZE     64
  87
  88 struct ima_digest_data {
  89         u8 algo;
  90         u8 length;
  91         union {
  92                 struct {
  93                         u8 unused;
  94                         u8 type;
  95                 } sha1;
  96                 struct {
  97                         u8 type;
  98                         u8 algo;
  99                 } ng;
 100                 u8 data[2];
 101         } xattr;
 102         u8 digest[0];
 103 } __packed;
 104
 105 /*
 106  * signature format v2 - for using with asymmetric keys
 107  */
 108 struct signature_v2_hdr {
 109         uint8_t type;           /* xattr type */
 110         uint8_t version;        /* signature format version */
 111         uint8_t hash_algo;      /* Digest algorithm [enum hash_algo] */
 112         __be32 keyid;           /* IMA key identifier - not X509/PGP specific */
 113         __be16 sig_size;        /* signature size */
 114         uint8_t sig[0];         /* signature payload */
 115 } __packed;
 116
 117 /* integrity data associated with an inode */
 118 struct integrity_iint_cache {
 119         struct rb_node rb_node; /* rooted in integrity_iint_tree */
 120         struct mutex mutex;     /* protects: version, flags, digest */
 121         struct inode *inode;    /* back pointer to inode in question */
 122         u64 version;            /* track inode changes */
 123         unsigned long flags;
 124         unsigned long measured_pcrs;
 125         unsigned long atomic_flags;
 126         enum integrity_status ima_file_status:4;
 127         enum integrity_status ima_mmap_status:4;
 128         enum integrity_status ima_bprm_status:4;
 129         enum integrity_status ima_read_status:4;
 130         enum integrity_status ima_creds_status:4;
 131         enum integrity_status evm_status:4;
 132         struct ima_digest_data *ima_hash;
 133 };
 134
 135 /* rbtree tree calls to lookup, insert, delete
 136  * integrity data associated with an inode.
 137  */
 138 struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
 139
 140 int integrity_kernel_read(struct file *file, loff_t offset,
 141                           void *addr, unsigned long count);
 142
 143 #define INTEGRITY_KEYRING_EVM           0
 144 #define INTEGRITY_KEYRING_IMA           1
 145 #define INTEGRITY_KEYRING_PLATFORM      2
 146 #define INTEGRITY_KEYRING_MAX           3
 147
 148 extern struct dentry *integrity_dir;
 149
 150 #ifdef CONFIG_INTEGRITY_SIGNATURE
 151
 152 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
 153                             const char *digest, int digestlen);
 154
 155 int __init integrity_init_keyring(const unsigned int id);
 156 int __init integrity_load_x509(const unsigned int id, const char *path);
 157 int __init integrity_load_cert(const unsigned int id, const char *source,
 158                                const void *data, size_t len, key_perm_t perm);
 159 #else
 160
 161 static inline int integrity_digsig_verify(const unsigned int id,
 162                                           const char *sig, int siglen,
 163                                           const char *digest, int digestlen)
 164 {
 165         return -EOPNOTSUPP;
 166 }
 167
 168 static inline int integrity_init_keyring(const unsigned int id)
 169 {
 170         return 0;
 171 }
 172
 173 static inline int __init integrity_load_cert(const unsigned int id,
 174                                              const char *source,
 175                                              const void *data, size_t len,
 176                                              key_perm_t perm)
 177 {
 178         return 0;
 179 }
 180 #endif /* CONFIG_INTEGRITY_SIGNATURE */
 181
 182 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
 183 int asymmetric_verify(struct key *keyring, const char *sig,
 184                       int siglen, const char *data, int datalen);
 185 #else
 186 static inline int asymmetric_verify(struct key *keyring, const char *sig,
 187                                     int siglen, const char *data, int datalen)
 188 {
 189         return -EOPNOTSUPP;
 190 }
 191 #endif
 192
 193 #ifdef CONFIG_IMA_LOAD_X509
 194 void __init ima_load_x509(void);
 195 #else
 196 static inline void ima_load_x509(void)
 197 {
 198 }
 199 #endif
 200
 201 #ifdef CONFIG_EVM_LOAD_X509
 202 void __init evm_load_x509(void);
 203 #else
 204 static inline void evm_load_x509(void)
 205 {
 206 }
 207 #endif
 208
 209 #ifdef CONFIG_INTEGRITY_AUDIT
 210 /* declarations */
 211 void integrity_audit_msg(int audit_msgno, struct inode *inode,
 212                          const unsigned char *fname, const char *op,
 213                          const char *cause, int result, int info);
 214
 215 static inline struct audit_buffer *
 216 integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type)
 217 {
 218         return audit_log_start(ctx, gfp_mask, type);
 219 }
 220
 221 #else
 222 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode,
 223                                        const unsigned char *fname,
 224                                        const char *op, const char *cause,
 225                                        int result, int info)
 226 {
 227 }
 228
 229 static inline struct audit_buffer *
 230 integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type)
 231 {
 232         return NULL;
 233 }
 234
 235 #endif
 236
 237 #ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
 238 void __init add_to_platform_keyring(const char *source, const void *data,
 239                                     size_t len);
 240 #else
 241 static inline void __init add_to_platform_keyring(const char *source,
 242                                                   const void *data, size_t len)
 243 {
 244 }
 245 #endif