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
  29 /* iint cache flags */
  30 #define IMA_ACTION_FLAGS        0xff000000
  31 #define IMA_DIGSIG              0x01000000
  32 #define IMA_DIGSIG_REQUIRED     0x02000000
  33
  34 #define IMA_DO_MASK             (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
  35                                  IMA_APPRAISE_SUBMASK)
  36 #define IMA_DONE_MASK           (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \
  37                                  IMA_COLLECTED | IMA_APPRAISED_SUBMASK)
  38
  39 /* iint subaction appraise cache flags */
  40 #define IMA_FILE_APPRAISE       0x00000100
  41 #define IMA_FILE_APPRAISED      0x00000200
  42 #define IMA_MMAP_APPRAISE       0x00000400
  43 #define IMA_MMAP_APPRAISED      0x00000800
  44 #define IMA_BPRM_APPRAISE       0x00001000
  45 #define IMA_BPRM_APPRAISED      0x00002000
  46 #define IMA_MODULE_APPRAISE     0x00004000
  47 #define IMA_MODULE_APPRAISED    0x00008000
  48 #define IMA_APPRAISE_SUBMASK    (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \
  49                                  IMA_BPRM_APPRAISE | IMA_MODULE_APPRAISE)
  50 #define IMA_APPRAISED_SUBMASK   (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
  51                                  IMA_BPRM_APPRAISED | IMA_MODULE_APPRAISED)
  52
  53 enum evm_ima_xattr_type {
  54         IMA_XATTR_DIGEST = 0x01,
  55         EVM_XATTR_HMAC,
  56         EVM_IMA_XATTR_DIGSIG,
  57         IMA_XATTR_DIGEST_NG,
  58 };
  59
  60 struct evm_ima_xattr_data {
  61         u8 type;
  62         u8 digest[SHA1_DIGEST_SIZE];
  63 } __packed;
  64
  65 #define IMA_MAX_DIGEST_SIZE     64
  66
  67 struct ima_digest_data {
  68         u8 algo;
  69         u8 length;
  70         union {
  71                 struct {
  72                         u8 unused;
  73                         u8 type;
  74                 } sha1;
  75                 struct {
  76                         u8 type;
  77                         u8 algo;
  78                 } ng;
  79                 u8 data[2];
  80         } xattr;
  81         u8 digest[0];
  82 } __packed;
  83
  84 /*
  85  * signature format v2 - for using with asymmetric keys
  86  */
  87 struct signature_v2_hdr {
  88         uint8_t type;           /* xattr type */
  89         uint8_t version;        /* signature format version */
  90         uint8_t hash_algo;      /* Digest algorithm [enum pkey_hash_algo] */
  91         uint32_t keyid;         /* IMA key identifier - not X509/PGP specific */
  92         uint16_t sig_size;      /* signature size */
  93         uint8_t sig[0];         /* signature payload */
  94 } __packed;
  95
  96 /* integrity data associated with an inode */
  97 struct integrity_iint_cache {
  98         struct rb_node rb_node; /* rooted in integrity_iint_tree */
  99         struct inode *inode;    /* back pointer to inode in question */
 100         u64 version;            /* track inode changes */
 101         unsigned long flags;
 102         enum integrity_status ima_file_status:4;
 103         enum integrity_status ima_mmap_status:4;
 104         enum integrity_status ima_bprm_status:4;
 105         enum integrity_status ima_module_status:4;
 106         enum integrity_status evm_status:4;
 107         struct ima_digest_data *ima_hash;
 108 };
 109
 110 /* rbtree tree calls to lookup, insert, delete
 111  * integrity data associated with an inode.
 112  */
 113 struct integrity_iint_cache *integrity_iint_insert(struct inode *inode);
 114 struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
 115
 116 #define INTEGRITY_KEYRING_EVM           0
 117 #define INTEGRITY_KEYRING_MODULE        1
 118 #define INTEGRITY_KEYRING_IMA           2
 119 #define INTEGRITY_KEYRING_MAX           3
 120
 121 #ifdef CONFIG_INTEGRITY_SIGNATURE
 122
 123 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
 124                             const char *digest, int digestlen);
 125
 126 #else
 127
 128 static inline int integrity_digsig_verify(const unsigned int id,
 129                                           const char *sig, int siglen,
 130                                           const char *digest, int digestlen)
 131 {
 132         return -EOPNOTSUPP;
 133 }
 134
 135 #endif /* CONFIG_INTEGRITY_SIGNATURE */
 136
 137 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
 138 int asymmetric_verify(struct key *keyring, const char *sig,
 139                       int siglen, const char *data, int datalen);
 140 #else
 141 static inline int asymmetric_verify(struct key *keyring, const char *sig,
 142                                     int siglen, const char *data, int datalen)
 143 {
 144         return -EOPNOTSUPP;
 145 }
 146 #endif
 147
 148 #ifdef CONFIG_INTEGRITY_AUDIT
 149 /* declarations */
 150 void integrity_audit_msg(int audit_msgno, struct inode *inode,
 151                          const unsigned char *fname, const char *op,
 152                          const char *cause, int result, int info);
 153 #else
 154 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode,
 155                                        const unsigned char *fname,
 156                                        const char *op, const char *cause,
 157                                        int result, int info)
 158 {
 159 }
 160 #endif
 161
 162 /* set during initialization */
 163 extern int iint_initialized;