1 /* 2 * This file describes the internal interface used by the labeler 3 * for calling the user-supplied memory allocation, validation, 4 * and locking routine. 5 * 6 * Author : Eamon Walsh <ewalsh@epoch.ncsc.mil> 7 */ 8 #ifndef _SELABEL_INTERNAL_H_ 9 #define _SELABEL_INTERNAL_H_ 10 11 #include <stdlib.h> 12 #include <stdarg.h> 13 #include <stdio.h> 14 #include <selinux/selinux.h> 15 #include <selinux/label.h> 16 #include "dso.h" 17 #include "sha1.h" 18 19 #if defined(ANDROID) || defined(__APPLE__) 20 // Android and Mac do not have fgets_unlocked() 21 #define fgets_unlocked(buf, size, fp) fgets(buf, size, fp) 22 #endif 23 24 /* 25 * Installed backends 26 */ 27 int selabel_file_init(struct selabel_handle *rec, 28 const struct selinux_opt *opts, 29 unsigned nopts) hidden; 30 int selabel_media_init(struct selabel_handle *rec, 31 const struct selinux_opt *opts, 32 unsigned nopts) hidden; 33 int selabel_x_init(struct selabel_handle *rec, 34 const struct selinux_opt *opts, 35 unsigned nopts) hidden; 36 int selabel_db_init(struct selabel_handle *rec, 37 const struct selinux_opt *opts, 38 unsigned nopts) hidden; 39 int selabel_property_init(struct selabel_handle *rec, 40 const struct selinux_opt *opts, 41 unsigned nopts) hidden; 42 int selabel_exact_match_init(struct selabel_handle *rec, 43 const struct selinux_opt *opts, 44 unsigned nopts) hidden; 45 46 /* 47 * Labeling internal structures 48 */ 49 50 /* 51 * Calculate an SHA1 hash of all the files used to build the specs. 52 * The hash value is held in rec->digest if SELABEL_OPT_DIGEST set. To 53 * calculate the hash the hashbuf will hold a concatenation of all the files 54 * used. This is released once the value has been calculated. 55 */ 56 #define DIGEST_SPECFILE_SIZE SHA1_HASH_SIZE 57 #define DIGEST_FILES_MAX 8 58 struct selabel_digest { 59 unsigned char *digest; /* SHA1 digest of specfiles */ 60 unsigned char *hashbuf; /* buffer to hold specfiles */ 61 size_t hashbuf_size; /* buffer size */ 62 size_t specfile_cnt; /* how many specfiles processed */ 63 char **specfile_list; /* and their names */ 64 }; 65 66 extern int digest_add_specfile(struct selabel_digest *digest, FILE *fp, 67 char *from_addr, 68 size_t buf_len, 69 const char *path); 70 extern void digest_gen_hash(struct selabel_digest *digest); 71 72 struct selabel_lookup_rec { 73 char * ctx_raw; 74 char * ctx_trans; 75 int validated; 76 unsigned lineno; 77 }; 78 79 struct selabel_handle { 80 /* arguments that were passed to selabel_open */ 81 unsigned int backend; 82 int validating; 83 84 /* labeling operations */ 85 struct selabel_lookup_rec *(*func_lookup) (struct selabel_handle *h, 86 const char *key, int type); 87 void (*func_close) (struct selabel_handle *h); 88 void (*func_stats) (struct selabel_handle *h); 89 bool (*func_partial_match) (struct selabel_handle *h, const char *key); 90 bool (*func_get_digests_all_partial_matches) (struct selabel_handle *h, 91 const char *key, 92 uint8_t **calculated_digest, 93 uint8_t **xattr_digest, 94 size_t *digest_len); 95 bool (*func_hash_all_partial_matches) (struct selabel_handle *h, 96 const char *key, uint8_t *digest); 97 struct selabel_lookup_rec *(*func_lookup_best_match) 98 (struct selabel_handle *h, 99 const char *key, 100 const char **aliases, 101 int type); 102 enum selabel_cmp_result (*func_cmp)(struct selabel_handle *h1, 103 struct selabel_handle *h2); 104 105 /* supports backend-specific state information */ 106 void *data; 107 108 /* 109 * The main spec file(s) used. Note for file contexts the local and/or 110 * homedirs could also have been used to resolve a context. 111 */ 112 size_t spec_files_len; 113 char **spec_files; 114 115 116 /* ptr to SHA1 hash information if SELABEL_OPT_DIGEST set */ 117 struct selabel_digest *digest; 118 }; 119 120 /* 121 * Validation function 122 */ 123 extern int 124 selabel_validate(struct selabel_handle *rec, 125 struct selabel_lookup_rec *contexts) hidden; 126 127 /* 128 * Compatibility support 129 */ 130 extern int myprintf_compat; 131 extern void __attribute__ ((format(printf, 1, 2))) 132 (*myprintf) (const char *fmt, ...) hidden; 133 134 #define COMPAT_LOG(type, fmt...) if (myprintf_compat) \ 135 myprintf(fmt); \ 136 else \ 137 selinux_log(type, fmt); 138 139 extern int 140 compat_validate(struct selabel_handle *rec, 141 struct selabel_lookup_rec *contexts, 142 const char *path, unsigned lineno) hidden; 143 144 /* 145 * The read_spec_entries function may be used to 146 * replace sscanf to read entries from spec files. 147 */ 148 extern int read_spec_entries(char *line_buf, const char **errbuf, int num_args, ...); 149 150 #endif /* _SELABEL_INTERNAL_H_ */ 151