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