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 #include <linux/types.h> 10 #include <linux/integrity.h> 11 #include <crypto/sha.h> 12 #include <linux/key.h> 13 #include <linux/audit.h> 14 15 /* iint action cache flags */ 16 #define IMA_MEASURE 0x00000001 17 #define IMA_MEASURED 0x00000002 18 #define IMA_APPRAISE 0x00000004 19 #define IMA_APPRAISED 0x00000008 20 /*#define IMA_COLLECT 0x00000010 do not use this flag */ 21 #define IMA_COLLECTED 0x00000020 22 #define IMA_AUDIT 0x00000040 23 #define IMA_AUDITED 0x00000080 24 #define IMA_HASH 0x00000100 25 #define IMA_HASHED 0x00000200 26 27 /* iint cache flags */ 28 #define IMA_ACTION_FLAGS 0xff000000 29 #define IMA_DIGSIG_REQUIRED 0x01000000 30 #define IMA_PERMIT_DIRECTIO 0x02000000 31 #define IMA_NEW_FILE 0x04000000 32 #define EVM_IMMUTABLE_DIGSIG 0x08000000 33 #define IMA_FAIL_UNVERIFIABLE_SIGS 0x10000000 34 35 #define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \ 36 IMA_HASH | IMA_APPRAISE_SUBMASK) 37 #define IMA_DONE_MASK (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \ 38 IMA_HASHED | IMA_COLLECTED | \ 39 IMA_APPRAISED_SUBMASK) 40 41 /* iint subaction appraise cache flags */ 42 #define IMA_FILE_APPRAISE 0x00001000 43 #define IMA_FILE_APPRAISED 0x00002000 44 #define IMA_MMAP_APPRAISE 0x00004000 45 #define IMA_MMAP_APPRAISED 0x00008000 46 #define IMA_BPRM_APPRAISE 0x00010000 47 #define IMA_BPRM_APPRAISED 0x00020000 48 #define IMA_READ_APPRAISE 0x00040000 49 #define IMA_READ_APPRAISED 0x00080000 50 #define IMA_CREDS_APPRAISE 0x00100000 51 #define IMA_CREDS_APPRAISED 0x00200000 52 #define IMA_APPRAISE_SUBMASK (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \ 53 IMA_BPRM_APPRAISE | IMA_READ_APPRAISE | \ 54 IMA_CREDS_APPRAISE) 55 #define IMA_APPRAISED_SUBMASK (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \ 56 IMA_BPRM_APPRAISED | IMA_READ_APPRAISED | \ 57 IMA_CREDS_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 data[]; 78 } __packed; 79 80 /* Only used in the EVM HMAC code. */ 81 struct evm_xattr { 82 struct evm_ima_xattr_data data; 83 u8 digest[SHA1_DIGEST_SIZE]; 84 } __packed; 85 86 #define IMA_MAX_DIGEST_SIZE 64 87 88 struct ima_digest_data { 89 u8 algo; 90 u8 length; 91 union { 92 struct { 93 u8 unused; 94 u8 type; 95 } sha1; 96 struct { 97 u8 type; 98 u8 algo; 99 } ng; 100 u8 data[2]; 101 } xattr; 102 u8 digest[0]; 103 } __packed; 104 105 /* 106 * signature format v2 - for using with asymmetric keys 107 */ 108 struct signature_v2_hdr { 109 uint8_t type; /* xattr type */ 110 uint8_t version; /* signature format version */ 111 uint8_t hash_algo; /* Digest algorithm [enum hash_algo] */ 112 __be32 keyid; /* IMA key identifier - not X509/PGP specific */ 113 __be16 sig_size; /* signature size */ 114 uint8_t sig[0]; /* signature payload */ 115 } __packed; 116 117 /* integrity data associated with an inode */ 118 struct integrity_iint_cache { 119 struct rb_node rb_node; /* rooted in integrity_iint_tree */ 120 struct mutex mutex; /* protects: version, flags, digest */ 121 struct inode *inode; /* back pointer to inode in question */ 122 u64 version; /* track inode changes */ 123 unsigned long flags; 124 unsigned long measured_pcrs; 125 unsigned long atomic_flags; 126 enum integrity_status ima_file_status:4; 127 enum integrity_status ima_mmap_status:4; 128 enum integrity_status ima_bprm_status:4; 129 enum integrity_status ima_read_status:4; 130 enum integrity_status ima_creds_status:4; 131 enum integrity_status evm_status:4; 132 struct ima_digest_data *ima_hash; 133 }; 134 135 /* rbtree tree calls to lookup, insert, delete 136 * integrity data associated with an inode. 137 */ 138 struct integrity_iint_cache *integrity_iint_find(struct inode *inode); 139 140 int integrity_kernel_read(struct file *file, loff_t offset, 141 void *addr, unsigned long count); 142 143 #define INTEGRITY_KEYRING_EVM 0 144 #define INTEGRITY_KEYRING_IMA 1 145 #define INTEGRITY_KEYRING_PLATFORM 2 146 #define INTEGRITY_KEYRING_MAX 3 147 148 extern struct dentry *integrity_dir; 149 150 #ifdef CONFIG_INTEGRITY_SIGNATURE 151 152 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen, 153 const char *digest, int digestlen); 154 155 int __init integrity_init_keyring(const unsigned int id); 156 int __init integrity_load_x509(const unsigned int id, const char *path); 157 int __init integrity_load_cert(const unsigned int id, const char *source, 158 const void *data, size_t len, key_perm_t perm); 159 #else 160 161 static inline int integrity_digsig_verify(const unsigned int id, 162 const char *sig, int siglen, 163 const char *digest, int digestlen) 164 { 165 return -EOPNOTSUPP; 166 } 167 168 static inline int integrity_init_keyring(const unsigned int id) 169 { 170 return 0; 171 } 172 173 static inline int __init integrity_load_cert(const unsigned int id, 174 const char *source, 175 const void *data, size_t len, 176 key_perm_t perm) 177 { 178 return 0; 179 } 180 #endif /* CONFIG_INTEGRITY_SIGNATURE */ 181 182 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS 183 int asymmetric_verify(struct key *keyring, const char *sig, 184 int siglen, const char *data, int datalen); 185 #else 186 static inline int asymmetric_verify(struct key *keyring, const char *sig, 187 int siglen, const char *data, int datalen) 188 { 189 return -EOPNOTSUPP; 190 } 191 #endif 192 193 #ifdef CONFIG_IMA_LOAD_X509 194 void __init ima_load_x509(void); 195 #else 196 static inline void ima_load_x509(void) 197 { 198 } 199 #endif 200 201 #ifdef CONFIG_EVM_LOAD_X509 202 void __init evm_load_x509(void); 203 #else 204 static inline void evm_load_x509(void) 205 { 206 } 207 #endif 208 209 #ifdef CONFIG_INTEGRITY_AUDIT 210 /* declarations */ 211 void integrity_audit_msg(int audit_msgno, struct inode *inode, 212 const unsigned char *fname, const char *op, 213 const char *cause, int result, int info); 214 215 static inline struct audit_buffer * 216 integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type) 217 { 218 return audit_log_start(ctx, gfp_mask, type); 219 } 220 221 #else 222 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode, 223 const unsigned char *fname, 224 const char *op, const char *cause, 225 int result, int info) 226 { 227 } 228 229 static inline struct audit_buffer * 230 integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type) 231 { 232 return NULL; 233 } 234 235 #endif 236 237 #ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING 238 void __init add_to_platform_keyring(const char *source, const void *data, 239 size_t len); 240 #else 241 static inline void __init add_to_platform_keyring(const char *source, 242 const void *data, size_t len) 243 { 244 } 245 #endif 246