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 #define IMA_MODSIG_ALLOWED      0x20000000
  35 #define IMA_CHECK_BLACKLIST     0x40000000
  36
  37 #define IMA_DO_MASK             (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
  38                                  IMA_HASH | IMA_APPRAISE_SUBMASK)
  39 #define IMA_DONE_MASK           (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \
  40                                  IMA_HASHED | IMA_COLLECTED | \
  41                                  IMA_APPRAISED_SUBMASK)
  42
  43 /* iint subaction appraise cache flags */
  44 #define IMA_FILE_APPRAISE       0x00001000
  45 #define IMA_FILE_APPRAISED      0x00002000
  46 #define IMA_MMAP_APPRAISE       0x00004000
  47 #define IMA_MMAP_APPRAISED      0x00008000
  48 #define IMA_BPRM_APPRAISE       0x00010000
  49 #define IMA_BPRM_APPRAISED      0x00020000
  50 #define IMA_READ_APPRAISE       0x00040000
  51 #define IMA_READ_APPRAISED      0x00080000
  52 #define IMA_CREDS_APPRAISE      0x00100000
  53 #define IMA_CREDS_APPRAISED     0x00200000
  54 #define IMA_APPRAISE_SUBMASK    (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \
  55                                  IMA_BPRM_APPRAISE | IMA_READ_APPRAISE | \
  56                                  IMA_CREDS_APPRAISE)
  57 #define IMA_APPRAISED_SUBMASK   (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
  58                                  IMA_BPRM_APPRAISED | IMA_READ_APPRAISED | \
  59                                  IMA_CREDS_APPRAISED)
  60
  61 /* iint cache atomic_flags */
  62 #define IMA_CHANGE_XATTR        0
  63 #define IMA_UPDATE_XATTR        1
  64 #define IMA_CHANGE_ATTR         2
  65 #define IMA_DIGSIG              3
  66 #define IMA_MUST_MEASURE        4
  67
  68 enum evm_ima_xattr_type {
  69         IMA_XATTR_DIGEST = 0x01,
  70         EVM_XATTR_HMAC,
  71         EVM_IMA_XATTR_DIGSIG,
  72         IMA_XATTR_DIGEST_NG,
  73         EVM_XATTR_PORTABLE_DIGSIG,
  74         IMA_XATTR_LAST
  75 };
  76
  77 struct evm_ima_xattr_data {
  78         u8 type;
  79         u8 data[];
  80 } __packed;
  81
  82 /* Only used in the EVM HMAC code. */
  83 struct evm_xattr {
  84         struct evm_ima_xattr_data data;
  85         u8 digest[SHA1_DIGEST_SIZE];
  86 } __packed;
  87
  88 #define IMA_MAX_DIGEST_SIZE     64
  89
  90 struct ima_digest_data {
  91         u8 algo;
  92         u8 length;
  93         union {
  94                 struct {
  95                         u8 unused;
  96                         u8 type;
  97                 } sha1;
  98                 struct {
  99                         u8 type;
 100                         u8 algo;
 101                 } ng;
 102                 u8 data[2];
 103         } xattr;
 104         u8 digest[0];
 105 } __packed;
 106
 107 /*
 108  * signature format v2 - for using with asymmetric keys
 109  */
 110 struct signature_v2_hdr {
 111         uint8_t type;           /* xattr type */
 112         uint8_t version;        /* signature format version */
 113         uint8_t hash_algo;      /* Digest algorithm [enum hash_algo] */
 114         __be32 keyid;           /* IMA key identifier - not X509/PGP specific */
 115         __be16 sig_size;        /* signature size */
 116         uint8_t sig[0];         /* signature payload */
 117 } __packed;
 118
 119 /* integrity data associated with an inode */
 120 struct integrity_iint_cache {
 121         struct rb_node rb_node; /* rooted in integrity_iint_tree */
 122         struct mutex mutex;     /* protects: version, flags, digest */
 123         struct inode *inode;    /* back pointer to inode in question */
 124         u64 version;            /* track inode changes */
 125         unsigned long flags;
 126         unsigned long measured_pcrs;
 127         unsigned long atomic_flags;
 128         enum integrity_status ima_file_status:4;
 129         enum integrity_status ima_mmap_status:4;
 130         enum integrity_status ima_bprm_status:4;
 131         enum integrity_status ima_read_status:4;
 132         enum integrity_status ima_creds_status:4;
 133         enum integrity_status evm_status:4;
 134         struct ima_digest_data *ima_hash;
 135 };
 136
 137 /* rbtree tree calls to lookup, insert, delete
 138  * integrity data associated with an inode.
 139  */
 140 struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
 141
 142 int integrity_kernel_read(struct file *file, loff_t offset,
 143                           void *addr, unsigned long count);
 144
 145 #define INTEGRITY_KEYRING_EVM           0
 146 #define INTEGRITY_KEYRING_IMA           1
 147 #define INTEGRITY_KEYRING_PLATFORM      2
 148 #define INTEGRITY_KEYRING_MAX           3
 149
 150 extern struct dentry *integrity_dir;
 151
 152 struct modsig;
 153
 154 #ifdef CONFIG_INTEGRITY_SIGNATURE
 155
 156 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
 157                             const char *digest, int digestlen);
 158 int integrity_modsig_verify(unsigned int id, const struct modsig *modsig);
 159
 160 int __init integrity_init_keyring(const unsigned int id);
 161 int __init integrity_load_x509(const unsigned int id, const char *path);
 162 int __init integrity_load_cert(const unsigned int id, const char *source,
 163                                const void *data, size_t len, key_perm_t perm);
 164 #else
 165
 166 static inline int integrity_digsig_verify(const unsigned int id,
 167                                           const char *sig, int siglen,
 168                                           const char *digest, int digestlen)
 169 {
 170         return -EOPNOTSUPP;
 171 }
 172
 173 static inline int integrity_modsig_verify(unsigned int id,
 174                                           const struct modsig *modsig)
 175 {
 176         return -EOPNOTSUPP;
 177 }
 178
 179 static inline int integrity_init_keyring(const unsigned int id)
 180 {
 181         return 0;
 182 }
 183
 184 static inline int __init integrity_load_cert(const unsigned int id,
 185                                              const char *source,
 186                                              const void *data, size_t len,
 187                                              key_perm_t perm)
 188 {
 189         return 0;
 190 }
 191 #endif /* CONFIG_INTEGRITY_SIGNATURE */
 192
 193 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
 194 int asymmetric_verify(struct key *keyring, const char *sig,
 195                       int siglen, const char *data, int datalen);
 196 #else
 197 static inline int asymmetric_verify(struct key *keyring, const char *sig,
 198                                     int siglen, const char *data, int datalen)
 199 {
 200         return -EOPNOTSUPP;
 201 }
 202 #endif
 203
 204 #ifdef CONFIG_IMA_APPRAISE_MODSIG
 205 int ima_modsig_verify(struct key *keyring, const struct modsig *modsig);
 206 #else
 207 static inline int ima_modsig_verify(struct key *keyring,
 208                                     const struct modsig *modsig)
 209 {
 210         return -EOPNOTSUPP;
 211 }
 212 #endif
 213
 214 #ifdef CONFIG_IMA_LOAD_X509
 215 void __init ima_load_x509(void);
 216 #else
 217 static inline void ima_load_x509(void)
 218 {
 219 }
 220 #endif
 221
 222 #ifdef CONFIG_EVM_LOAD_X509
 223 void __init evm_load_x509(void);
 224 #else
 225 static inline void evm_load_x509(void)
 226 {
 227 }
 228 #endif
 229
 230 #ifdef CONFIG_INTEGRITY_AUDIT
 231 /* declarations */
 232 void integrity_audit_msg(int audit_msgno, struct inode *inode,
 233                          const unsigned char *fname, const char *op,
 234                          const char *cause, int result, int info);
 235
 236 static inline struct audit_buffer *
 237 integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type)
 238 {
 239         return audit_log_start(ctx, gfp_mask, type);
 240 }
 241
 242 #else
 243 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode,
 244                                        const unsigned char *fname,
 245                                        const char *op, const char *cause,
 246                                        int result, int info)
 247 {
 248 }
 249
 250 static inline struct audit_buffer *
 251 integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type)
 252 {
 253         return NULL;
 254 }
 255
 256 #endif
 257
 258 #ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
 259 void __init add_to_platform_keyring(const char *source, const void *data,
 260                                     size_t len);
 261 #else
 262 static inline void __init add_to_platform_keyring(const char *source,
 263                                                   const void *data, size_t len)
 264 {
 265 }
 266 #endif