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