| 1 | /************************************************* |
| 2 | * Exim - an Internet mail transport agent * |
| 3 | *************************************************/ |
| 4 | |
| 5 | /* Copyright (c) University of Cambridge 1995 - 2015 */ |
| 6 | /* See the file NOTICE for conditions of use and distribution. */ |
| 7 | |
| 8 | /* The idea for this code came from Matthew Byng-Maddick, but his original has |
| 9 | been heavily reworked a lot for Exim 4 (and it now uses stat() (more precisely: |
| 10 | lstat()) rather than a directory scan). */ |
| 11 | |
| 12 | |
| 13 | #include "../exim.h" |
| 14 | #include "lf_functions.h" |
| 15 | |
| 16 | |
| 17 | |
| 18 | /************************************************* |
| 19 | * Open entry point * |
| 20 | *************************************************/ |
| 21 | |
| 22 | /* See local README for interface description. We open the directory to test |
| 23 | whether it exists and whether it is searchable. However, we don't need to keep |
| 24 | it open, because the "search" can be done by a call to lstat() rather than |
| 25 | actually scanning through the list of files. */ |
| 26 | |
| 27 | static void * |
| 28 | dsearch_open(uschar *dirname, uschar **errmsg) |
| 29 | { |
| 30 | DIR *dp = opendir(CS dirname); |
| 31 | if (dp == NULL) |
| 32 | { |
| 33 | int save_errno = errno; |
| 34 | *errmsg = string_open_failed(errno, "%s for directory search", dirname); |
| 35 | errno = save_errno; |
| 36 | return NULL; |
| 37 | } |
| 38 | closedir(dp); |
| 39 | return (void *)(-1); |
| 40 | } |
| 41 | |
| 42 | |
| 43 | /************************************************* |
| 44 | * Check entry point * |
| 45 | *************************************************/ |
| 46 | |
| 47 | /* The handle will always be (void *)(-1), but don't try casting it to an |
| 48 | integer as this gives warnings on 64-bit systems. */ |
| 49 | |
| 50 | BOOL |
| 51 | static dsearch_check(void *handle, uschar *filename, int modemask, uid_t *owners, |
| 52 | gid_t *owngroups, uschar **errmsg) |
| 53 | { |
| 54 | handle = handle; |
| 55 | return lf_check_file(-1, filename, S_IFDIR, modemask, owners, owngroups, |
| 56 | "dsearch", errmsg) == 0; |
| 57 | } |
| 58 | |
| 59 | |
| 60 | /************************************************* |
| 61 | * Find entry point * |
| 62 | *************************************************/ |
| 63 | |
| 64 | /* See local README for interface description. We use lstat() instead of |
| 65 | scanning the directory, as it is hopefully faster to let the OS do the scanning |
| 66 | for us. */ |
| 67 | |
| 68 | int |
| 69 | static dsearch_find(void *handle, uschar *dirname, const uschar *keystring, int length, |
| 70 | uschar **result, uschar **errmsg, uint *do_cache) |
| 71 | { |
| 72 | struct stat statbuf; |
| 73 | int save_errno; |
| 74 | uschar filename[PATH_MAX]; |
| 75 | |
| 76 | handle = handle; /* Keep picky compilers happy */ |
| 77 | length = length; |
| 78 | do_cache = do_cache; |
| 79 | |
| 80 | if (Ustrchr(keystring, '/') != 0) |
| 81 | { |
| 82 | *errmsg = string_sprintf("key for dsearch lookup contains a slash: %s", |
| 83 | keystring); |
| 84 | return DEFER; |
| 85 | } |
| 86 | |
| 87 | if (!string_format(filename, sizeof(filename), "%s/%s", dirname, keystring)) |
| 88 | { |
| 89 | *errmsg = US"path name too long"; |
| 90 | return DEFER; |
| 91 | } |
| 92 | |
| 93 | if (Ulstat(filename, &statbuf) >= 0) |
| 94 | { |
| 95 | *result = string_copy(keystring); |
| 96 | return OK; |
| 97 | } |
| 98 | |
| 99 | if (errno == ENOENT) return FAIL; |
| 100 | |
| 101 | save_errno = errno; |
| 102 | *errmsg = string_sprintf("%s: lstat failed", filename); |
| 103 | errno = save_errno; |
| 104 | return DEFER; |
| 105 | } |
| 106 | |
| 107 | |
| 108 | /************************************************* |
| 109 | * Close entry point * |
| 110 | *************************************************/ |
| 111 | |
| 112 | /* See local README for interface description */ |
| 113 | |
| 114 | void |
| 115 | static dsearch_close(void *handle) |
| 116 | { |
| 117 | handle = handle; /* Avoid compiler warning */ |
| 118 | } |
| 119 | |
| 120 | |
| 121 | /************************************************* |
| 122 | * Version reporting entry point * |
| 123 | *************************************************/ |
| 124 | |
| 125 | /* See local README for interface description. */ |
| 126 | |
| 127 | #include "../version.h" |
| 128 | |
| 129 | void |
| 130 | dsearch_version_report(FILE *f) |
| 131 | { |
| 132 | #ifdef DYNLOOKUP |
| 133 | fprintf(f, "Library version: dsearch: Exim version %s\n", EXIM_VERSION_STR); |
| 134 | #endif |
| 135 | } |
| 136 | |
| 137 | |
| 138 | static lookup_info _lookup_info = { |
| 139 | US"dsearch", /* lookup name */ |
| 140 | lookup_absfile, /* uses absolute file name */ |
| 141 | dsearch_open, /* open function */ |
| 142 | dsearch_check, /* check function */ |
| 143 | dsearch_find, /* find function */ |
| 144 | dsearch_close, /* close function */ |
| 145 | NULL, /* no tidy function */ |
| 146 | NULL, /* no quoting function */ |
| 147 | dsearch_version_report /* version reporting */ |
| 148 | }; |
| 149 | |
| 150 | #ifdef DYNLOOKUP |
| 151 | #define dsearch_lookup_module_info _lookup_module_info |
| 152 | #endif |
| 153 | |
| 154 | static lookup_info *_lookup_list[] = { &_lookup_info }; |
| 155 | lookup_module_info dsearch_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 1 }; |
| 156 | |
| 157 | /* End of lookups/dsearch.c */ |