security/integrity/integrity.h

   1 /*
   2  * Copyright (C) 2009-2010 IBM Corporation
   3  *
   4  * Authors:
   5  * Mimi Zohar <zohar@us.ibm.com>
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License as
   9  * published by the Free Software Foundation, version 2 of the
  10  * License.
  11  *
  12  */
  13
  14 #include <linux/types.h>
  15 #include <linux/integrity.h>
  16 #include <crypto/sha.h>
  17 #include <linux/key.h>
  18
  19 /* iint action cache flags */
  20 #define IMA_MEASURE             0x00000001
  21 #define IMA_MEASURED            0x00000002
  22 #define IMA_APPRAISE            0x00000004
  23 #define IMA_APPRAISED           0x00000008
  24 /*#define IMA_COLLECT           0x00000010  do not use this flag */
  25 #define IMA_COLLECTED           0x00000020
  26 #define IMA_AUDIT               0x00000040
  27 #define IMA_AUDITED             0x00000080
  28 #define IMA_HASH                0x00000100
  29 #define IMA_HASHED              0x00000200
  30
  31 /* iint cache flags */
  32 #define IMA_ACTION_FLAGS        0xff000000
  33 #define IMA_ACTION_RULE_FLAGS   0x06000000
  34 #define IMA_DIGSIG_REQUIRED     0x01000000
  35 #define IMA_PERMIT_DIRECTIO     0x02000000
  36 #define IMA_NEW_FILE            0x04000000
  37 #define EVM_IMMUTABLE_DIGSIG    0x08000000
  38
  39 #define IMA_DO_MASK             (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
  40                                  IMA_HASH | IMA_APPRAISE_SUBMASK)
  41 #define IMA_DONE_MASK           (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \
  42                                  IMA_HASHED | IMA_COLLECTED | \
  43                                  IMA_APPRAISED_SUBMASK)
  44
  45 /* iint subaction appraise cache flags */
  46 #define IMA_FILE_APPRAISE       0x00001000
  47 #define IMA_FILE_APPRAISED      0x00002000
  48 #define IMA_MMAP_APPRAISE       0x00004000
  49 #define IMA_MMAP_APPRAISED      0x00008000
  50 #define IMA_BPRM_APPRAISE       0x00010000
  51 #define IMA_BPRM_APPRAISED      0x00020000
  52 #define IMA_READ_APPRAISE       0x00040000
  53 #define IMA_READ_APPRAISED      0x00080000
  54 #define IMA_APPRAISE_SUBMASK    (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \
  55                                  IMA_BPRM_APPRAISE | IMA_READ_APPRAISE)
  56 #define IMA_APPRAISED_SUBMASK   (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
  57                                  IMA_BPRM_APPRAISED | IMA_READ_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 digest[SHA1_DIGEST_SIZE];
  78 } __packed;
  79
  80 #define IMA_MAX_DIGEST_SIZE     64
  81
  82 struct ima_digest_data {
  83         u8 algo;
  84         u8 length;
  85         union {
  86                 struct {
  87                         u8 unused;
  88                         u8 type;
  89                 } sha1;
  90                 struct {
  91                         u8 type;
  92                         u8 algo;
  93                 } ng;
  94                 u8 data[2];
  95         } xattr;
  96         u8 digest[0];
  97 } __packed;
  98
  99 /*
 100  * signature format v2 - for using with asymmetric keys
 101  */
 102 struct signature_v2_hdr {
 103         uint8_t type;           /* xattr type */
 104         uint8_t version;        /* signature format version */
 105         uint8_t hash_algo;      /* Digest algorithm [enum hash_algo] */
 106         __be32 keyid;           /* IMA key identifier - not X509/PGP specific */
 107         __be16 sig_size;        /* signature size */
 108         uint8_t sig[0];         /* signature payload */
 109 } __packed;
 110
 111 /* integrity data associated with an inode */
 112 struct integrity_iint_cache {
 113         struct rb_node rb_node; /* rooted in integrity_iint_tree */
 114         struct mutex mutex;     /* protects: version, flags, digest */
 115         struct inode *inode;    /* back pointer to inode in question */
 116         u64 version;            /* track inode changes */
 117         unsigned long flags;
 118         unsigned long measured_pcrs;
 119         unsigned long atomic_flags;
 120         enum integrity_status ima_file_status:4;
 121         enum integrity_status ima_mmap_status:4;
 122         enum integrity_status ima_bprm_status:4;
 123         enum integrity_status ima_read_status:4;
 124         enum integrity_status evm_status:4;
 125         struct ima_digest_data *ima_hash;
 126 };
 127
 128 /* rbtree tree calls to lookup, insert, delete
 129  * integrity data associated with an inode.
 130  */
 131 struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
 132
 133 int integrity_kernel_read(struct file *file, loff_t offset,
 134                           void *addr, unsigned long count);
 135
 136 #define INTEGRITY_KEYRING_EVM           0
 137 #define INTEGRITY_KEYRING_IMA           1
 138 #define INTEGRITY_KEYRING_MODULE        2
 139 #define INTEGRITY_KEYRING_MAX           3
 140
 141 #ifdef CONFIG_INTEGRITY_SIGNATURE
 142
 143 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
 144                             const char *digest, int digestlen);
 145
 146 int __init integrity_init_keyring(const unsigned int id);
 147 int __init integrity_load_x509(const unsigned int id, const char *path);
 148 #else
 149
 150 static inline int integrity_digsig_verify(const unsigned int id,
 151                                           const char *sig, int siglen,
 152                                           const char *digest, int digestlen)
 153 {
 154         return -EOPNOTSUPP;
 155 }
 156
 157 static inline int integrity_init_keyring(const unsigned int id)
 158 {
 159         return 0;
 160 }
 161 #endif /* CONFIG_INTEGRITY_SIGNATURE */
 162
 163 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
 164 int asymmetric_verify(struct key *keyring, const char *sig,
 165                       int siglen, const char *data, int datalen);
 166 #else
 167 static inline int asymmetric_verify(struct key *keyring, const char *sig,
 168                                     int siglen, const char *data, int datalen)
 169 {
 170         return -EOPNOTSUPP;
 171 }
 172 #endif
 173
 174 #ifdef CONFIG_IMA_LOAD_X509
 175 void __init ima_load_x509(void);
 176 #else
 177 static inline void ima_load_x509(void)
 178 {
 179 }
 180 #endif
 181
 182 #ifdef CONFIG_EVM_LOAD_X509
 183 void __init evm_load_x509(void);
 184 #else
 185 static inline void evm_load_x509(void)
 186 {
 187 }
 188 #endif
 189
 190 #ifdef CONFIG_INTEGRITY_AUDIT
 191 /* declarations */
 192 void integrity_audit_msg(int audit_msgno, struct inode *inode,
 193                          const unsigned char *fname, const char *op,
 194                          const char *cause, int result, int info);
 195 #else
 196 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode,
 197                                        const unsigned char *fname,
 198                                        const char *op, const char *cause,
 199                                        int result, int info)
 200 {
 201 }
 202 #endif