1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (C) 2009-2010 IBM Corporation 4 * 5 * Authors: 6 * Mimi Zohar <zohar@us.ibm.com> 7 */ 8 9 #ifdef pr_fmt 10 #undef pr_fmt 11 #endif 12 13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 14 15 #include <linux/types.h> 16 #include <linux/integrity.h> 17 #include <crypto/sha1.h> 18 #include <crypto/hash.h> 19 #include <linux/key.h> 20 #include <linux/audit.h> 21 22 /* iint action cache flags */ 23 #define IMA_MEASURE 0x00000001 24 #define IMA_MEASURED 0x00000002 25 #define IMA_APPRAISE 0x00000004 26 #define IMA_APPRAISED 0x00000008 27 /*#define IMA_COLLECT 0x00000010 do not use this flag */ 28 #define IMA_COLLECTED 0x00000020 29 #define IMA_AUDIT 0x00000040 30 #define IMA_AUDITED 0x00000080 31 #define IMA_HASH 0x00000100 32 #define IMA_HASHED 0x00000200 33 34 /* iint policy rule cache flags */ 35 #define IMA_NONACTION_FLAGS 0xff000000 36 #define IMA_DIGSIG_REQUIRED 0x01000000 37 #define IMA_PERMIT_DIRECTIO 0x02000000 38 #define IMA_NEW_FILE 0x04000000 39 #define EVM_IMMUTABLE_DIGSIG 0x08000000 40 #define IMA_FAIL_UNVERIFIABLE_SIGS 0x10000000 41 #define IMA_MODSIG_ALLOWED 0x20000000 42 #define IMA_CHECK_BLACKLIST 0x40000000 43 44 #define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \ 45 IMA_HASH | IMA_APPRAISE_SUBMASK) 46 #define IMA_DONE_MASK (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \ 47 IMA_HASHED | IMA_COLLECTED | \ 48 IMA_APPRAISED_SUBMASK) 49 50 /* iint subaction appraise cache flags */ 51 #define IMA_FILE_APPRAISE 0x00001000 52 #define IMA_FILE_APPRAISED 0x00002000 53 #define IMA_MMAP_APPRAISE 0x00004000 54 #define IMA_MMAP_APPRAISED 0x00008000 55 #define IMA_BPRM_APPRAISE 0x00010000 56 #define IMA_BPRM_APPRAISED 0x00020000 57 #define IMA_READ_APPRAISE 0x00040000 58 #define IMA_READ_APPRAISED 0x00080000 59 #define IMA_CREDS_APPRAISE 0x00100000 60 #define IMA_CREDS_APPRAISED 0x00200000 61 #define IMA_APPRAISE_SUBMASK (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \ 62 IMA_BPRM_APPRAISE | IMA_READ_APPRAISE | \ 63 IMA_CREDS_APPRAISE) 64 #define IMA_APPRAISED_SUBMASK (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \ 65 IMA_BPRM_APPRAISED | IMA_READ_APPRAISED | \ 66 IMA_CREDS_APPRAISED) 67 68 /* iint cache atomic_flags */ 69 #define IMA_CHANGE_XATTR 0 70 #define IMA_UPDATE_XATTR 1 71 #define IMA_CHANGE_ATTR 2 72 #define IMA_DIGSIG 3 73 #define IMA_MUST_MEASURE 4 74 75 enum evm_ima_xattr_type { 76 IMA_XATTR_DIGEST = 0x01, 77 EVM_XATTR_HMAC, 78 EVM_IMA_XATTR_DIGSIG, 79 IMA_XATTR_DIGEST_NG, 80 EVM_XATTR_PORTABLE_DIGSIG, 81 IMA_XATTR_LAST 82 }; 83 84 struct evm_ima_xattr_data { 85 u8 type; 86 u8 data[]; 87 } __packed; 88 89 /* Only used in the EVM HMAC code. */ 90 struct evm_xattr { 91 struct evm_ima_xattr_data data; 92 u8 digest[SHA1_DIGEST_SIZE]; 93 } __packed; 94 95 #define IMA_MAX_DIGEST_SIZE 64 96 97 struct ima_digest_data { 98 u8 algo; 99 u8 length; 100 union { 101 struct { 102 u8 unused; 103 u8 type; 104 } sha1; 105 struct { 106 u8 type; 107 u8 algo; 108 } ng; 109 u8 data[2]; 110 } xattr; 111 u8 digest[]; 112 } __packed; 113 114 /* 115 * Instead of wrapping the ima_digest_data struct inside a local structure 116 * with the maximum hash size, define ima_max_digest_data struct. 117 */ 118 struct ima_max_digest_data { 119 struct ima_digest_data hdr; 120 u8 digest[HASH_MAX_DIGESTSIZE]; 121 } __packed; 122 123 /* 124 * signature format v2 - for using with asymmetric keys 125 */ 126 struct signature_v2_hdr { 127 uint8_t type; /* xattr type */ 128 uint8_t version; /* signature format version */ 129 uint8_t hash_algo; /* Digest algorithm [enum hash_algo] */ 130 __be32 keyid; /* IMA key identifier - not X509/PGP specific */ 131 __be16 sig_size; /* signature size */ 132 uint8_t sig[]; /* signature payload */ 133 } __packed; 134 135 /* integrity data associated with an inode */ 136 struct integrity_iint_cache { 137 struct rb_node rb_node; /* rooted in integrity_iint_tree */ 138 struct mutex mutex; /* protects: version, flags, digest */ 139 struct inode *inode; /* back pointer to inode in question */ 140 u64 version; /* track inode changes */ 141 unsigned long flags; 142 unsigned long measured_pcrs; 143 unsigned long atomic_flags; 144 enum integrity_status ima_file_status:4; 145 enum integrity_status ima_mmap_status:4; 146 enum integrity_status ima_bprm_status:4; 147 enum integrity_status ima_read_status:4; 148 enum integrity_status ima_creds_status:4; 149 enum integrity_status evm_status:4; 150 struct ima_digest_data *ima_hash; 151 }; 152 153 /* rbtree tree calls to lookup, insert, delete 154 * integrity data associated with an inode. 155 */ 156 struct integrity_iint_cache *integrity_iint_find(struct inode *inode); 157 158 int integrity_kernel_read(struct file *file, loff_t offset, 159 void *addr, unsigned long count); 160 161 #define INTEGRITY_KEYRING_EVM 0 162 #define INTEGRITY_KEYRING_IMA 1 163 #define INTEGRITY_KEYRING_PLATFORM 2 164 #define INTEGRITY_KEYRING_MAX 3 165 166 extern struct dentry *integrity_dir; 167 168 struct modsig; 169 170 #ifdef CONFIG_INTEGRITY_SIGNATURE 171 172 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen, 173 const char *digest, int digestlen); 174 int integrity_modsig_verify(unsigned int id, const struct modsig *modsig); 175 176 int __init integrity_init_keyring(const unsigned int id); 177 int __init integrity_load_x509(const unsigned int id, const char *path); 178 int __init integrity_load_cert(const unsigned int id, const char *source, 179 const void *data, size_t len, key_perm_t perm); 180 #else 181 182 static inline int integrity_digsig_verify(const unsigned int id, 183 const char *sig, int siglen, 184 const char *digest, int digestlen) 185 { 186 return -EOPNOTSUPP; 187 } 188 189 static inline int integrity_modsig_verify(unsigned int id, 190 const struct modsig *modsig) 191 { 192 return -EOPNOTSUPP; 193 } 194 195 static inline int integrity_init_keyring(const unsigned int id) 196 { 197 return 0; 198 } 199 200 static inline int __init integrity_load_cert(const unsigned int id, 201 const char *source, 202 const void *data, size_t len, 203 key_perm_t perm) 204 { 205 return 0; 206 } 207 #endif /* CONFIG_INTEGRITY_SIGNATURE */ 208 209 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS 210 int asymmetric_verify(struct key *keyring, const char *sig, 211 int siglen, const char *data, int datalen); 212 #else 213 static inline int asymmetric_verify(struct key *keyring, const char *sig, 214 int siglen, const char *data, int datalen) 215 { 216 return -EOPNOTSUPP; 217 } 218 #endif 219 220 #ifdef CONFIG_IMA_APPRAISE_MODSIG 221 int ima_modsig_verify(struct key *keyring, const struct modsig *modsig); 222 #else 223 static inline int ima_modsig_verify(struct key *keyring, 224 const struct modsig *modsig) 225 { 226 return -EOPNOTSUPP; 227 } 228 #endif 229 230 #ifdef CONFIG_IMA_LOAD_X509 231 void __init ima_load_x509(void); 232 #else 233 static inline void ima_load_x509(void) 234 { 235 } 236 #endif 237 238 #ifdef CONFIG_EVM_LOAD_X509 239 void __init evm_load_x509(void); 240 #else 241 static inline void evm_load_x509(void) 242 { 243 } 244 #endif 245 246 #ifdef CONFIG_INTEGRITY_AUDIT 247 /* declarations */ 248 void integrity_audit_msg(int audit_msgno, struct inode *inode, 249 const unsigned char *fname, const char *op, 250 const char *cause, int result, int info); 251 252 void integrity_audit_message(int audit_msgno, struct inode *inode, 253 const unsigned char *fname, const char *op, 254 const char *cause, int result, int info, 255 int errno); 256 257 static inline struct audit_buffer * 258 integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type) 259 { 260 return audit_log_start(ctx, gfp_mask, type); 261 } 262 263 #else 264 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode, 265 const unsigned char *fname, 266 const char *op, const char *cause, 267 int result, int info) 268 { 269 } 270 271 static inline void integrity_audit_message(int audit_msgno, 272 struct inode *inode, 273 const unsigned char *fname, 274 const char *op, const char *cause, 275 int result, int info, int errno) 276 { 277 } 278 279 static inline struct audit_buffer * 280 integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type) 281 { 282 return NULL; 283 } 284 285 #endif 286 287 #ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING 288 void __init add_to_platform_keyring(const char *source, const void *data, 289 size_t len); 290 #else 291 static inline void __init add_to_platform_keyring(const char *source, 292 const void *data, size_t len) 293 { 294 } 295 #endif 296