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_DIGSIG_REQUIRED 0x01000000 34 #define IMA_PERMIT_DIRECTIO 0x02000000 35 #define IMA_NEW_FILE 0x04000000 36 #define EVM_IMMUTABLE_DIGSIG 0x08000000 37 #define IMA_FAIL_UNVERIFIABLE_SIGS 0x10000000 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_CREDS_APPRAISE 0x00100000 55 #define IMA_CREDS_APPRAISED 0x00200000 56 #define IMA_APPRAISE_SUBMASK (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \ 57 IMA_BPRM_APPRAISE | IMA_READ_APPRAISE | \ 58 IMA_CREDS_APPRAISE) 59 #define IMA_APPRAISED_SUBMASK (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \ 60 IMA_BPRM_APPRAISED | IMA_READ_APPRAISED | \ 61 IMA_CREDS_APPRAISED) 62 63 /* iint cache atomic_flags */ 64 #define IMA_CHANGE_XATTR 0 65 #define IMA_UPDATE_XATTR 1 66 #define IMA_CHANGE_ATTR 2 67 #define IMA_DIGSIG 3 68 #define IMA_MUST_MEASURE 4 69 70 enum evm_ima_xattr_type { 71 IMA_XATTR_DIGEST = 0x01, 72 EVM_XATTR_HMAC, 73 EVM_IMA_XATTR_DIGSIG, 74 IMA_XATTR_DIGEST_NG, 75 EVM_XATTR_PORTABLE_DIGSIG, 76 IMA_XATTR_LAST 77 }; 78 79 struct evm_ima_xattr_data { 80 u8 type; 81 u8 digest[SHA1_DIGEST_SIZE]; 82 } __packed; 83 84 #define IMA_MAX_DIGEST_SIZE 64 85 86 struct ima_digest_data { 87 u8 algo; 88 u8 length; 89 union { 90 struct { 91 u8 unused; 92 u8 type; 93 } sha1; 94 struct { 95 u8 type; 96 u8 algo; 97 } ng; 98 u8 data[2]; 99 } xattr; 100 u8 digest[0]; 101 } __packed; 102 103 /* 104 * signature format v2 - for using with asymmetric keys 105 */ 106 struct signature_v2_hdr { 107 uint8_t type; /* xattr type */ 108 uint8_t version; /* signature format version */ 109 uint8_t hash_algo; /* Digest algorithm [enum hash_algo] */ 110 __be32 keyid; /* IMA key identifier - not X509/PGP specific */ 111 __be16 sig_size; /* signature size */ 112 uint8_t sig[0]; /* signature payload */ 113 } __packed; 114 115 /* integrity data associated with an inode */ 116 struct integrity_iint_cache { 117 struct rb_node rb_node; /* rooted in integrity_iint_tree */ 118 struct mutex mutex; /* protects: version, flags, digest */ 119 struct inode *inode; /* back pointer to inode in question */ 120 u64 version; /* track inode changes */ 121 unsigned long flags; 122 unsigned long measured_pcrs; 123 unsigned long atomic_flags; 124 enum integrity_status ima_file_status:4; 125 enum integrity_status ima_mmap_status:4; 126 enum integrity_status ima_bprm_status:4; 127 enum integrity_status ima_read_status:4; 128 enum integrity_status ima_creds_status:4; 129 enum integrity_status evm_status:4; 130 struct ima_digest_data *ima_hash; 131 }; 132 133 /* rbtree tree calls to lookup, insert, delete 134 * integrity data associated with an inode. 135 */ 136 struct integrity_iint_cache *integrity_iint_find(struct inode *inode); 137 138 int integrity_kernel_read(struct file *file, loff_t offset, 139 void *addr, unsigned long count); 140 141 #define INTEGRITY_KEYRING_EVM 0 142 #define INTEGRITY_KEYRING_IMA 1 143 #define INTEGRITY_KEYRING_MODULE 2 144 #define INTEGRITY_KEYRING_MAX 3 145 146 #ifdef CONFIG_INTEGRITY_SIGNATURE 147 148 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen, 149 const char *digest, int digestlen); 150 151 int __init integrity_init_keyring(const unsigned int id); 152 int __init integrity_load_x509(const unsigned int id, const char *path); 153 #else 154 155 static inline int integrity_digsig_verify(const unsigned int id, 156 const char *sig, int siglen, 157 const char *digest, int digestlen) 158 { 159 return -EOPNOTSUPP; 160 } 161 162 static inline int integrity_init_keyring(const unsigned int id) 163 { 164 return 0; 165 } 166 #endif /* CONFIG_INTEGRITY_SIGNATURE */ 167 168 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS 169 int asymmetric_verify(struct key *keyring, const char *sig, 170 int siglen, const char *data, int datalen); 171 #else 172 static inline int asymmetric_verify(struct key *keyring, const char *sig, 173 int siglen, const char *data, int datalen) 174 { 175 return -EOPNOTSUPP; 176 } 177 #endif 178 179 #ifdef CONFIG_IMA_LOAD_X509 180 void __init ima_load_x509(void); 181 #else 182 static inline void ima_load_x509(void) 183 { 184 } 185 #endif 186 187 #ifdef CONFIG_EVM_LOAD_X509 188 void __init evm_load_x509(void); 189 #else 190 static inline void evm_load_x509(void) 191 { 192 } 193 #endif 194 195 #ifdef CONFIG_INTEGRITY_AUDIT 196 /* declarations */ 197 void integrity_audit_msg(int audit_msgno, struct inode *inode, 198 const unsigned char *fname, const char *op, 199 const char *cause, int result, int info); 200 #else 201 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode, 202 const unsigned char *fname, 203 const char *op, const char *cause, 204 int result, int info) 205 { 206 } 207 #endif 208