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 #define IMA_FAIL_UNVERIFIABLE_SIGS 0x10000000 39 40 #define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \ 41 IMA_HASH | IMA_APPRAISE_SUBMASK) 42 #define IMA_DONE_MASK (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \ 43 IMA_HASHED | IMA_COLLECTED | \ 44 IMA_APPRAISED_SUBMASK) 45 46 /* iint subaction appraise cache flags */ 47 #define IMA_FILE_APPRAISE 0x00001000 48 #define IMA_FILE_APPRAISED 0x00002000 49 #define IMA_MMAP_APPRAISE 0x00004000 50 #define IMA_MMAP_APPRAISED 0x00008000 51 #define IMA_BPRM_APPRAISE 0x00010000 52 #define IMA_BPRM_APPRAISED 0x00020000 53 #define IMA_READ_APPRAISE 0x00040000 54 #define IMA_READ_APPRAISED 0x00080000 55 #define IMA_CREDS_APPRAISE 0x00100000 56 #define IMA_CREDS_APPRAISED 0x00200000 57 #define IMA_APPRAISE_SUBMASK (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \ 58 IMA_BPRM_APPRAISE | IMA_READ_APPRAISE | \ 59 IMA_CREDS_APPRAISE) 60 #define IMA_APPRAISED_SUBMASK (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \ 61 IMA_BPRM_APPRAISED | IMA_READ_APPRAISED | \ 62 IMA_CREDS_APPRAISED) 63 64 /* iint cache atomic_flags */ 65 #define IMA_CHANGE_XATTR 0 66 #define IMA_UPDATE_XATTR 1 67 #define IMA_CHANGE_ATTR 2 68 #define IMA_DIGSIG 3 69 #define IMA_MUST_MEASURE 4 70 71 enum evm_ima_xattr_type { 72 IMA_XATTR_DIGEST = 0x01, 73 EVM_XATTR_HMAC, 74 EVM_IMA_XATTR_DIGSIG, 75 IMA_XATTR_DIGEST_NG, 76 EVM_XATTR_PORTABLE_DIGSIG, 77 IMA_XATTR_LAST 78 }; 79 80 struct evm_ima_xattr_data { 81 u8 type; 82 u8 digest[SHA1_DIGEST_SIZE]; 83 } __packed; 84 85 #define IMA_MAX_DIGEST_SIZE 64 86 87 struct ima_digest_data { 88 u8 algo; 89 u8 length; 90 union { 91 struct { 92 u8 unused; 93 u8 type; 94 } sha1; 95 struct { 96 u8 type; 97 u8 algo; 98 } ng; 99 u8 data[2]; 100 } xattr; 101 u8 digest[0]; 102 } __packed; 103 104 /* 105 * signature format v2 - for using with asymmetric keys 106 */ 107 struct signature_v2_hdr { 108 uint8_t type; /* xattr type */ 109 uint8_t version; /* signature format version */ 110 uint8_t hash_algo; /* Digest algorithm [enum hash_algo] */ 111 __be32 keyid; /* IMA key identifier - not X509/PGP specific */ 112 __be16 sig_size; /* signature size */ 113 uint8_t sig[0]; /* signature payload */ 114 } __packed; 115 116 /* integrity data associated with an inode */ 117 struct integrity_iint_cache { 118 struct rb_node rb_node; /* rooted in integrity_iint_tree */ 119 struct mutex mutex; /* protects: version, flags, digest */ 120 struct inode *inode; /* back pointer to inode in question */ 121 u64 version; /* track inode changes */ 122 unsigned long flags; 123 unsigned long measured_pcrs; 124 unsigned long atomic_flags; 125 enum integrity_status ima_file_status:4; 126 enum integrity_status ima_mmap_status:4; 127 enum integrity_status ima_bprm_status:4; 128 enum integrity_status ima_read_status:4; 129 enum integrity_status ima_creds_status:4; 130 enum integrity_status evm_status:4; 131 struct ima_digest_data *ima_hash; 132 }; 133 134 /* rbtree tree calls to lookup, insert, delete 135 * integrity data associated with an inode. 136 */ 137 struct integrity_iint_cache *integrity_iint_find(struct inode *inode); 138 139 int integrity_kernel_read(struct file *file, loff_t offset, 140 void *addr, unsigned long count); 141 142 #define INTEGRITY_KEYRING_EVM 0 143 #define INTEGRITY_KEYRING_IMA 1 144 #define INTEGRITY_KEYRING_MODULE 2 145 #define INTEGRITY_KEYRING_MAX 3 146 147 #ifdef CONFIG_INTEGRITY_SIGNATURE 148 149 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen, 150 const char *digest, int digestlen); 151 152 int __init integrity_init_keyring(const unsigned int id); 153 int __init integrity_load_x509(const unsigned int id, const char *path); 154 #else 155 156 static inline int integrity_digsig_verify(const unsigned int id, 157 const char *sig, int siglen, 158 const char *digest, int digestlen) 159 { 160 return -EOPNOTSUPP; 161 } 162 163 static inline int integrity_init_keyring(const unsigned int id) 164 { 165 return 0; 166 } 167 #endif /* CONFIG_INTEGRITY_SIGNATURE */ 168 169 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS 170 int asymmetric_verify(struct key *keyring, const char *sig, 171 int siglen, const char *data, int datalen); 172 #else 173 static inline int asymmetric_verify(struct key *keyring, const char *sig, 174 int siglen, const char *data, int datalen) 175 { 176 return -EOPNOTSUPP; 177 } 178 #endif 179 180 #ifdef CONFIG_IMA_LOAD_X509 181 void __init ima_load_x509(void); 182 #else 183 static inline void ima_load_x509(void) 184 { 185 } 186 #endif 187 188 #ifdef CONFIG_EVM_LOAD_X509 189 void __init evm_load_x509(void); 190 #else 191 static inline void evm_load_x509(void) 192 { 193 } 194 #endif 195 196 #ifdef CONFIG_INTEGRITY_AUDIT 197 /* declarations */ 198 void integrity_audit_msg(int audit_msgno, struct inode *inode, 199 const unsigned char *fname, const char *op, 200 const char *cause, int result, int info); 201 #else 202 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode, 203 const unsigned char *fname, 204 const char *op, const char *cause, 205 int result, int info) 206 { 207 } 208 #endif 209