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
  37 #define IMA_DO_MASK             (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
  38                                  IMA_APPRAISE_SUBMASK)
  39 #define IMA_DONE_MASK           (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \
  40                                  IMA_COLLECTED | IMA_APPRAISED_SUBMASK)
  41
  42 /* iint subaction appraise cache flags */
  43 #define IMA_FILE_APPRAISE       0x00000100
  44 #define IMA_FILE_APPRAISED      0x00000200
  45 #define IMA_MMAP_APPRAISE       0x00000400
  46 #define IMA_MMAP_APPRAISED      0x00000800
  47 #define IMA_BPRM_APPRAISE       0x00001000
  48 #define IMA_BPRM_APPRAISED      0x00002000
  49 #define IMA_READ_APPRAISE       0x00004000
  50 #define IMA_READ_APPRAISED      0x00008000
  51 #define IMA_APPRAISE_SUBMASK    (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \
  52                                  IMA_BPRM_APPRAISE | IMA_READ_APPRAISE)
  53 #define IMA_APPRAISED_SUBMASK   (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
  54                                  IMA_BPRM_APPRAISED | IMA_READ_APPRAISED)
  55
  56 enum evm_ima_xattr_type {
  57         IMA_XATTR_DIGEST = 0x01,
  58         EVM_XATTR_HMAC,
  59         EVM_IMA_XATTR_DIGSIG,
  60         IMA_XATTR_DIGEST_NG,
  61         IMA_XATTR_LAST
  62 };
  63
  64 struct evm_ima_xattr_data {
  65         u8 type;
  66         u8 digest[SHA1_DIGEST_SIZE];
  67 } __packed;
  68
  69 #define IMA_MAX_DIGEST_SIZE     64
  70
  71 struct ima_digest_data {
  72         u8 algo;
  73         u8 length;
  74         union {
  75                 struct {
  76                         u8 unused;
  77                         u8 type;
  78                 } sha1;
  79                 struct {
  80                         u8 type;
  81                         u8 algo;
  82                 } ng;
  83                 u8 data[2];
  84         } xattr;
  85         u8 digest[0];
  86 } __packed;
  87
  88 /*
  89  * signature format v2 - for using with asymmetric keys
  90  */
  91 struct signature_v2_hdr {
  92         uint8_t type;           /* xattr type */
  93         uint8_t version;        /* signature format version */
  94         uint8_t hash_algo;      /* Digest algorithm [enum hash_algo] */
  95         uint32_t keyid;         /* IMA key identifier - not X509/PGP specific */
  96         uint16_t sig_size;      /* signature size */
  97         uint8_t sig[0];         /* signature payload */
  98 } __packed;
  99
 100 /* integrity data associated with an inode */
 101 struct integrity_iint_cache {
 102         struct rb_node rb_node; /* rooted in integrity_iint_tree */
 103         struct inode *inode;    /* back pointer to inode in question */
 104         u64 version;            /* track inode changes */
 105         unsigned long flags;
 106         enum integrity_status ima_file_status:4;
 107         enum integrity_status ima_mmap_status:4;
 108         enum integrity_status ima_bprm_status:4;
 109         enum integrity_status ima_read_status:4;
 110         enum integrity_status evm_status:4;
 111         struct ima_digest_data *ima_hash;
 112 };
 113
 114 /* rbtree tree calls to lookup, insert, delete
 115  * integrity data associated with an inode.
 116  */
 117 struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
 118
 119 int integrity_kernel_read(struct file *file, loff_t offset,
 120                           char *addr, unsigned long count);
 121 int __init integrity_read_file(const char *path, char **data);
 122
 123 #define INTEGRITY_KEYRING_EVM           0
 124 #define INTEGRITY_KEYRING_IMA           1
 125 #define INTEGRITY_KEYRING_MODULE        2
 126 #define INTEGRITY_KEYRING_MAX           3
 127
 128 #ifdef CONFIG_INTEGRITY_SIGNATURE
 129
 130 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
 131                             const char *digest, int digestlen);
 132
 133 int __init integrity_init_keyring(const unsigned int id);
 134 int __init integrity_load_x509(const unsigned int id, const char *path);
 135 #else
 136
 137 static inline int integrity_digsig_verify(const unsigned int id,
 138                                           const char *sig, int siglen,
 139                                           const char *digest, int digestlen)
 140 {
 141         return -EOPNOTSUPP;
 142 }
 143
 144 static inline int integrity_init_keyring(const unsigned int id)
 145 {
 146         return 0;
 147 }
 148 #endif /* CONFIG_INTEGRITY_SIGNATURE */
 149
 150 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
 151 int asymmetric_verify(struct key *keyring, const char *sig,
 152                       int siglen, const char *data, int datalen);
 153 #else
 154 static inline int asymmetric_verify(struct key *keyring, const char *sig,
 155                                     int siglen, const char *data, int datalen)
 156 {
 157         return -EOPNOTSUPP;
 158 }
 159 #endif
 160
 161 #ifdef CONFIG_IMA_LOAD_X509
 162 void __init ima_load_x509(void);
 163 #else
 164 static inline void ima_load_x509(void)
 165 {
 166 }
 167 #endif
 168
 169 #ifdef CONFIG_EVM_LOAD_X509
 170 void __init evm_load_x509(void);
 171 #else
 172 static inline void evm_load_x509(void)
 173 {
 174 }
 175 #endif
 176
 177 #ifdef CONFIG_INTEGRITY_AUDIT
 178 /* declarations */
 179 void integrity_audit_msg(int audit_msgno, struct inode *inode,
 180                          const unsigned char *fname, const char *op,
 181                          const char *cause, int result, int info);
 182 #else
 183 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode,
 184                                        const unsigned char *fname,
 185                                        const char *op, const char *cause,
 186                                        int result, int info)
 187 {
 188 }
 189 #endif