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_ACTION_RULE_FLAGS   0x06000000
  32 #define IMA_DIGSIG              0x01000000
  33 #define IMA_DIGSIG_REQUIRED     0x02000000
  34 #define IMA_PERMIT_DIRECTIO     0x04000000
  35 #define IMA_NEW_FILE            0x08000000
  36 #define EVM_IMMUTABLE_DIGSIG    0x10000000
  37
  38 #define IMA_DO_MASK             (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
  39                                  IMA_APPRAISE_SUBMASK)
  40 #define IMA_DONE_MASK           (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \
  41                                  IMA_COLLECTED | IMA_APPRAISED_SUBMASK)
  42
  43 /* iint subaction appraise cache flags */
  44 #define IMA_FILE_APPRAISE       0x00000100
  45 #define IMA_FILE_APPRAISED      0x00000200
  46 #define IMA_MMAP_APPRAISE       0x00000400
  47 #define IMA_MMAP_APPRAISED      0x00000800
  48 #define IMA_BPRM_APPRAISE       0x00001000
  49 #define IMA_BPRM_APPRAISED      0x00002000
  50 #define IMA_READ_APPRAISE       0x00004000
  51 #define IMA_READ_APPRAISED      0x00008000
  52 #define IMA_APPRAISE_SUBMASK    (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \
  53                                  IMA_BPRM_APPRAISE | IMA_READ_APPRAISE)
  54 #define IMA_APPRAISED_SUBMASK   (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
  55                                  IMA_BPRM_APPRAISED | IMA_READ_APPRAISED)
  56
  57 enum evm_ima_xattr_type {
  58         IMA_XATTR_DIGEST = 0x01,
  59         EVM_XATTR_HMAC,
  60         EVM_IMA_XATTR_DIGSIG,
  61         IMA_XATTR_DIGEST_NG,
  62         EVM_XATTR_PORTABLE_DIGSIG,
  63         IMA_XATTR_LAST
  64 };
  65
  66 struct evm_ima_xattr_data {
  67         u8 type;
  68         u8 digest[SHA1_DIGEST_SIZE];
  69 } __packed;
  70
  71 #define IMA_MAX_DIGEST_SIZE     64
  72
  73 struct ima_digest_data {
  74         u8 algo;
  75         u8 length;
  76         union {
  77                 struct {
  78                         u8 unused;
  79                         u8 type;
  80                 } sha1;
  81                 struct {
  82                         u8 type;
  83                         u8 algo;
  84                 } ng;
  85                 u8 data[2];
  86         } xattr;
  87         u8 digest[0];
  88 } __packed;
  89
  90 /*
  91  * signature format v2 - for using with asymmetric keys
  92  */
  93 struct signature_v2_hdr {
  94         uint8_t type;           /* xattr type */
  95         uint8_t version;        /* signature format version */
  96         uint8_t hash_algo;      /* Digest algorithm [enum hash_algo] */
  97         __be32 keyid;           /* IMA key identifier - not X509/PGP specific */
  98         __be16 sig_size;        /* signature size */
  99         uint8_t sig[0];         /* signature payload */
 100 } __packed;
 101
 102 /* integrity data associated with an inode */
 103 struct integrity_iint_cache {
 104         struct rb_node rb_node; /* rooted in integrity_iint_tree */
 105         struct inode *inode;    /* back pointer to inode in question */
 106         u64 version;            /* track inode changes */
 107         unsigned long flags;
 108         unsigned long measured_pcrs;
 109         enum integrity_status ima_file_status:4;
 110         enum integrity_status ima_mmap_status:4;
 111         enum integrity_status ima_bprm_status:4;
 112         enum integrity_status ima_read_status:4;
 113         enum integrity_status evm_status:4;
 114         struct ima_digest_data *ima_hash;
 115 };
 116
 117 /* rbtree tree calls to lookup, insert, delete
 118  * integrity data associated with an inode.
 119  */
 120 struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
 121
 122 int integrity_kernel_read(struct file *file, loff_t offset,
 123                           void *addr, unsigned long count);
 124
 125 #define INTEGRITY_KEYRING_EVM           0
 126 #define INTEGRITY_KEYRING_IMA           1
 127 #define INTEGRITY_KEYRING_MODULE        2
 128 #define INTEGRITY_KEYRING_MAX           3
 129
 130 #ifdef CONFIG_INTEGRITY_SIGNATURE
 131
 132 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
 133                             const char *digest, int digestlen);
 134
 135 int __init integrity_init_keyring(const unsigned int id);
 136 int __init integrity_load_x509(const unsigned int id, const char *path);
 137 #else
 138
 139 static inline int integrity_digsig_verify(const unsigned int id,
 140                                           const char *sig, int siglen,
 141                                           const char *digest, int digestlen)
 142 {
 143         return -EOPNOTSUPP;
 144 }
 145
 146 static inline int integrity_init_keyring(const unsigned int id)
 147 {
 148         return 0;
 149 }
 150 #endif /* CONFIG_INTEGRITY_SIGNATURE */
 151
 152 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
 153 int asymmetric_verify(struct key *keyring, const char *sig,
 154                       int siglen, const char *data, int datalen);
 155 #else
 156 static inline int asymmetric_verify(struct key *keyring, const char *sig,
 157                                     int siglen, const char *data, int datalen)
 158 {
 159         return -EOPNOTSUPP;
 160 }
 161 #endif
 162
 163 #ifdef CONFIG_IMA_LOAD_X509
 164 void __init ima_load_x509(void);
 165 #else
 166 static inline void ima_load_x509(void)
 167 {
 168 }
 169 #endif
 170
 171 #ifdef CONFIG_EVM_LOAD_X509
 172 void __init evm_load_x509(void);
 173 #else
 174 static inline void evm_load_x509(void)
 175 {
 176 }
 177 #endif
 178
 179 #ifdef CONFIG_INTEGRITY_AUDIT
 180 /* declarations */
 181 void integrity_audit_msg(int audit_msgno, struct inode *inode,
 182                          const unsigned char *fname, const char *op,
 183                          const char *cause, int result, int info);
 184 #else
 185 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode,
 186                                        const unsigned char *fname,
 187                                        const char *op, const char *cause,
 188                                        int result, int info)
 189 {
 190 }
 191 #endif