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 #define IMA_PERMIT_DIRECTIO     0x04000000
  34
  35 #define IMA_DO_MASK             (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
  36                                  IMA_APPRAISE_SUBMASK)
  37 #define IMA_DONE_MASK           (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \
  38                                  IMA_COLLECTED | IMA_APPRAISED_SUBMASK)
  39
  40 /* iint subaction appraise cache flags */
  41 #define IMA_FILE_APPRAISE       0x00000100
  42 #define IMA_FILE_APPRAISED      0x00000200
  43 #define IMA_MMAP_APPRAISE       0x00000400
  44 #define IMA_MMAP_APPRAISED      0x00000800
  45 #define IMA_BPRM_APPRAISE       0x00001000
  46 #define IMA_BPRM_APPRAISED      0x00002000
  47 #define IMA_MODULE_APPRAISE     0x00004000
  48 #define IMA_MODULE_APPRAISED    0x00008000
  49 #define IMA_APPRAISE_SUBMASK    (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \
  50                                  IMA_BPRM_APPRAISE | IMA_MODULE_APPRAISE)
  51 #define IMA_APPRAISED_SUBMASK   (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
  52                                  IMA_BPRM_APPRAISED | IMA_MODULE_APPRAISED)
  53
  54 enum evm_ima_xattr_type {
  55         IMA_XATTR_DIGEST = 0x01,
  56         EVM_XATTR_HMAC,
  57         EVM_IMA_XATTR_DIGSIG,
  58         IMA_XATTR_DIGEST_NG,
  59 };
  60
  61 struct evm_ima_xattr_data {
  62         u8 type;
  63         u8 digest[SHA1_DIGEST_SIZE];
  64 } __packed;
  65
  66 #define IMA_MAX_DIGEST_SIZE     64
  67
  68 struct ima_digest_data {
  69         u8 algo;
  70         u8 length;
  71         union {
  72                 struct {
  73                         u8 unused;
  74                         u8 type;
  75                 } sha1;
  76                 struct {
  77                         u8 type;
  78                         u8 algo;
  79                 } ng;
  80                 u8 data[2];
  81         } xattr;
  82         u8 digest[0];
  83 } __packed;
  84
  85 /*
  86  * signature format v2 - for using with asymmetric keys
  87  */
  88 struct signature_v2_hdr {
  89         uint8_t type;           /* xattr type */
  90         uint8_t version;        /* signature format version */
  91         uint8_t hash_algo;      /* Digest algorithm [enum pkey_hash_algo] */
  92         uint32_t keyid;         /* IMA key identifier - not X509/PGP specific */
  93         uint16_t sig_size;      /* signature size */
  94         uint8_t sig[0];         /* signature payload */
  95 } __packed;
  96
  97 /* integrity data associated with an inode */
  98 struct integrity_iint_cache {
  99         struct rb_node rb_node; /* rooted in integrity_iint_tree */
 100         struct inode *inode;    /* back pointer to inode in question */
 101         u64 version;            /* track inode changes */
 102         unsigned long flags;
 103         enum integrity_status ima_file_status:4;
 104         enum integrity_status ima_mmap_status:4;
 105         enum integrity_status ima_bprm_status:4;
 106         enum integrity_status ima_module_status:4;
 107         enum integrity_status evm_status:4;
 108         struct ima_digest_data *ima_hash;
 109 };
 110
 111 /* rbtree tree calls to lookup, insert, delete
 112  * integrity data associated with an inode.
 113  */
 114 struct integrity_iint_cache *integrity_iint_insert(struct inode *inode);
 115 struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
 116
 117 #define INTEGRITY_KEYRING_EVM           0
 118 #define INTEGRITY_KEYRING_MODULE        1
 119 #define INTEGRITY_KEYRING_IMA           2
 120 #define INTEGRITY_KEYRING_MAX           3
 121
 122 #ifdef CONFIG_INTEGRITY_SIGNATURE
 123
 124 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
 125                             const char *digest, int digestlen);
 126
 127 #else
 128
 129 static inline int integrity_digsig_verify(const unsigned int id,
 130                                           const char *sig, int siglen,
 131                                           const char *digest, int digestlen)
 132 {
 133         return -EOPNOTSUPP;
 134 }
 135
 136 #endif /* CONFIG_INTEGRITY_SIGNATURE */
 137
 138 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
 139 int asymmetric_verify(struct key *keyring, const char *sig,
 140                       int siglen, const char *data, int datalen);
 141 #else
 142 static inline int asymmetric_verify(struct key *keyring, const char *sig,
 143                                     int siglen, const char *data, int datalen)
 144 {
 145         return -EOPNOTSUPP;
 146 }
 147 #endif
 148
 149 #ifdef CONFIG_INTEGRITY_AUDIT
 150 /* declarations */
 151 void integrity_audit_msg(int audit_msgno, struct inode *inode,
 152                          const unsigned char *fname, const char *op,
 153                          const char *cause, int result, int info);
 154 #else
 155 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode,
 156                                        const unsigned char *fname,
 157                                        const char *op, const char *cause,
 158                                        int result, int info)
 159 {
 160 }
 161 #endif
 162
 163 /* set during initialization */
 164 extern int iint_initialized;