diff options
Diffstat (limited to 'src/lookups/dsearch.c')
| -rw-r--r-- | src/lookups/dsearch.c | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/src/lookups/dsearch.c b/src/lookups/dsearch.c new file mode 100644 index 0000000..a769102 --- /dev/null +++ b/src/lookups/dsearch.c @@ -0,0 +1,190 @@ +/************************************************* +* Exim - an Internet mail transport agent * +*************************************************/ + +/* Copyright (c) The Exim Maintainers 2020 - 2022 */ +/* Copyright (c) University of Cambridge 1995 - 2015 */ +/* See the file NOTICE for conditions of use and distribution. */ + +/* The idea for this code came from Matthew Byng-Maddick, but his original has +been heavily reworked a lot for Exim 4 (and it now uses stat() (more precisely: +lstat()) rather than a directory scan). */ + + +#include "../exim.h" +#include "lf_functions.h" + + + +/************************************************* +* Open entry point * +*************************************************/ + +/* See local README for interface description. We open the directory to test +whether it exists and whether it is searchable. However, we don't need to keep +it open, because the "search" can be done by a call to lstat() rather than +actually scanning through the list of files. */ + +static void * +dsearch_open(const uschar * dirname, uschar ** errmsg) +{ +DIR * dp = exim_opendir(dirname); +if (!dp) + { + *errmsg = string_open_failed("%s for directory search", dirname); + return NULL; + } +closedir(dp); +return (void *)(-1); +} + + +/************************************************* +* Check entry point * +*************************************************/ + +/* The handle will always be (void *)(-1), but don't try casting it to an +integer as this gives warnings on 64-bit systems. */ + +static BOOL +dsearch_check(void * handle, const uschar * filename, int modemask, + uid_t * owners, gid_t * owngroups, uschar ** errmsg) +{ +handle = handle; +if (*filename == '/') + return lf_check_file(-1, filename, S_IFDIR, modemask, owners, owngroups, + "dsearch", errmsg) == 0; +*errmsg = string_sprintf("dirname '%s' for dsearch is not absolute", filename); +return FALSE; +} + + +/************************************************* +* Find entry point * +*************************************************/ + +#define RET_FULL BIT(0) +#define FILTER_TYPE BIT(1) +#define FILTER_ALL BIT(1) +#define FILTER_FILE BIT(2) +#define FILTER_DIR BIT(3) +#define FILTER_SUBDIR BIT(4) + +/* See local README for interface description. We use lstat() instead of +scanning the directory, as it is hopefully faster to let the OS do the scanning +for us. */ + +static int +dsearch_find(void * handle, const uschar * dirname, const uschar * keystring, + int length, uschar ** result, uschar ** errmsg, uint * do_cache, + const uschar * opts) +{ +struct stat statbuf; +int save_errno; +uschar * filename; +unsigned flags = 0; + +if (Ustrchr(keystring, '/') != 0) + { + *errmsg = string_sprintf("key for dsearch lookup contains a slash: %s", + keystring); + return DEFER; + } + +if (opts) + { + int sep = ','; + uschar * ele; + + while ((ele = string_nextinlist(&opts, &sep, NULL, 0))) + if (Ustrcmp(ele, "ret=full") == 0) + flags |= RET_FULL; + else if (Ustrncmp(ele, "filter=", 7) == 0) + { + ele += 7; + if (Ustrcmp(ele, "file") == 0) + flags |= FILTER_TYPE | FILTER_FILE; + else if (Ustrcmp(ele, "dir") == 0) + flags |= FILTER_TYPE | FILTER_DIR; + else if (Ustrcmp(ele, "subdir") == 0) + flags |= FILTER_TYPE | FILTER_SUBDIR; /* like dir but not "." or ".." */ + } + } + +filename = string_sprintf("%s/%s", dirname, keystring); +if ( Ulstat(filename, &statbuf) >= 0 + && ( !(flags & FILTER_TYPE) + || (flags & FILTER_FILE && S_ISREG(statbuf.st_mode)) + || ( flags & (FILTER_DIR | FILTER_SUBDIR) + && S_ISDIR(statbuf.st_mode) + && ( flags & FILTER_DIR + || keystring[0] != '.' + || keystring[1] && keystring[1] != '.' + ) ) ) ) + { + /* Since the filename exists in the filesystem, we can return a + non-tainted result. */ + *result = string_copy_taint(flags & RET_FULL ? filename : keystring, GET_UNTAINTED); + return OK; + } + +if (errno == ENOENT || errno == 0) return FAIL; + +save_errno = errno; +*errmsg = string_sprintf("%s: lstat: %s", filename, strerror(errno)); +errno = save_errno; +return DEFER; +} + + +/************************************************* +* Close entry point * +*************************************************/ + +/* See local README for interface description */ + +void +static dsearch_close(void *handle) +{ +handle = handle; /* Avoid compiler warning */ +} + + +/************************************************* +* Version reporting entry point * +*************************************************/ + +/* See local README for interface description. */ + +#include "../version.h" + +gstring * +dsearch_version_report(gstring * g) +{ +#ifdef DYNLOOKUP +g = string_fmt_append(g, "Library version: dsearch: Exim version %s\n", EXIM_VERSION_STR); +#endif +return g; +} + + +static lookup_info _lookup_info = { + .name = US"dsearch", /* lookup name */ + .type = lookup_absfile, /* uses absolute file name */ + .open = dsearch_open, /* open function */ + .check = dsearch_check, /* check function */ + .find = dsearch_find, /* find function */ + .close = dsearch_close, /* close function */ + .tidy = NULL, /* no tidy function */ + .quote = NULL, /* no quoting function */ + .version_report = dsearch_version_report /* version reporting */ +}; + +#ifdef DYNLOOKUP +#define dsearch_lookup_module_info _lookup_module_info +#endif + +static lookup_info *_lookup_list[] = { &_lookup_info }; +lookup_module_info dsearch_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 1 }; + +/* End of lookups/dsearch.c */ |