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_REQUIRED 0x01000000 33 #define IMA_PERMIT_DIRECTIO 0x02000000 34 #define IMA_NEW_FILE 0x04000000 35 #define EVM_IMMUTABLE_DIGSIG 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 /* iint cache atomic_flags */ 57 #define IMA_CHANGE_XATTR 0 58 #define IMA_UPDATE_XATTR 1 59 #define IMA_CHANGE_ATTR 2 60 #define IMA_DIGSIG 3 61 #define IMA_MUST_MEASURE 4 62 63 enum evm_ima_xattr_type { 64 IMA_XATTR_DIGEST = 0x01, 65 EVM_XATTR_HMAC, 66 EVM_IMA_XATTR_DIGSIG, 67 IMA_XATTR_DIGEST_NG, 68 EVM_XATTR_PORTABLE_DIGSIG, 69 IMA_XATTR_LAST 70 }; 71 72 struct evm_ima_xattr_data { 73 u8 type; 74 u8 digest[SHA1_DIGEST_SIZE]; 75 } __packed; 76 77 #define IMA_MAX_DIGEST_SIZE 64 78 79 struct ima_digest_data { 80 u8 algo; 81 u8 length; 82 union { 83 struct { 84 u8 unused; 85 u8 type; 86 } sha1; 87 struct { 88 u8 type; 89 u8 algo; 90 } ng; 91 u8 data[2]; 92 } xattr; 93 u8 digest[0]; 94 } __packed; 95 96 /* 97 * signature format v2 - for using with asymmetric keys 98 */ 99 struct signature_v2_hdr { 100 uint8_t type; /* xattr type */ 101 uint8_t version; /* signature format version */ 102 uint8_t hash_algo; /* Digest algorithm [enum hash_algo] */ 103 __be32 keyid; /* IMA key identifier - not X509/PGP specific */ 104 __be16 sig_size; /* signature size */ 105 uint8_t sig[0]; /* signature payload */ 106 } __packed; 107 108 /* integrity data associated with an inode */ 109 struct integrity_iint_cache { 110 struct rb_node rb_node; /* rooted in integrity_iint_tree */ 111 struct mutex mutex; /* protects: version, flags, digest */ 112 struct inode *inode; /* back pointer to inode in question */ 113 u64 version; /* track inode changes */ 114 unsigned long flags; 115 unsigned long measured_pcrs; 116 unsigned long atomic_flags; 117 enum integrity_status ima_file_status:4; 118 enum integrity_status ima_mmap_status:4; 119 enum integrity_status ima_bprm_status:4; 120 enum integrity_status ima_read_status:4; 121 enum integrity_status evm_status:4; 122 struct ima_digest_data *ima_hash; 123 }; 124 125 /* rbtree tree calls to lookup, insert, delete 126 * integrity data associated with an inode. 127 */ 128 struct integrity_iint_cache *integrity_iint_find(struct inode *inode); 129 130 int integrity_kernel_read(struct file *file, loff_t offset, 131 void *addr, unsigned long count); 132 133 #define INTEGRITY_KEYRING_EVM 0 134 #define INTEGRITY_KEYRING_IMA 1 135 #define INTEGRITY_KEYRING_MODULE 2 136 #define INTEGRITY_KEYRING_MAX 3 137 138 #ifdef CONFIG_INTEGRITY_SIGNATURE 139 140 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen, 141 const char *digest, int digestlen); 142 143 int __init integrity_init_keyring(const unsigned int id); 144 int __init integrity_load_x509(const unsigned int id, const char *path); 145 #else 146 147 static inline int integrity_digsig_verify(const unsigned int id, 148 const char *sig, int siglen, 149 const char *digest, int digestlen) 150 { 151 return -EOPNOTSUPP; 152 } 153 154 static inline int integrity_init_keyring(const unsigned int id) 155 { 156 return 0; 157 } 158 #endif /* CONFIG_INTEGRITY_SIGNATURE */ 159 160 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS 161 int asymmetric_verify(struct key *keyring, const char *sig, 162 int siglen, const char *data, int datalen); 163 #else 164 static inline int asymmetric_verify(struct key *keyring, const char *sig, 165 int siglen, const char *data, int datalen) 166 { 167 return -EOPNOTSUPP; 168 } 169 #endif 170 171 #ifdef CONFIG_IMA_LOAD_X509 172 void __init ima_load_x509(void); 173 #else 174 static inline void ima_load_x509(void) 175 { 176 } 177 #endif 178 179 #ifdef CONFIG_EVM_LOAD_X509 180 void __init evm_load_x509(void); 181 #else 182 static inline void evm_load_x509(void) 183 { 184 } 185 #endif 186 187 #ifdef CONFIG_INTEGRITY_AUDIT 188 /* declarations */ 189 void integrity_audit_msg(int audit_msgno, struct inode *inode, 190 const unsigned char *fname, const char *op, 191 const char *cause, int result, int info); 192 #else 193 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode, 194 const unsigned char *fname, 195 const char *op, const char *cause, 196 int result, int info) 197 { 198 } 199 #endif 200