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