projects / exim.git / blame
| Commit | Line | Data |
|---|---|---|
| 0756eb3c PH |
1 | /************************************************* |
| 2 | * Exim - an Internet mail transport agent * | |
| 3 | *************************************************/ | |
| 4 | ||
| 0a49a7a4 | 5 | /* Copyright (c) University of Cambridge 1995 - 2009 */ |
| 0756eb3c PH |
6 | /* See the file NOTICE for conditions of use and distribution. */ |
| 7 | ||
| 8 | ||
| 9 | #include "../exim.h" | |
| 10 | #include "lf_functions.h" | |
| 11 | ||
| 12 | ||
| 13 | ||
| 14 | /************************************************* | |
| 15 | * Check a file's credentials * | |
| 16 | *************************************************/ | |
| 17 | ||
| 18 | /* fstat can normally be expected to work on an open file, but there are some | |
| 19 | NFS states where it may not. | |
| 20 | ||
| 21 | Arguments: | |
| 22 | fd an open file descriptor or -1 | |
| 23 | filename a file name if fd is -1 | |
| 24 | s_type type of file (S_IFREG or S_IFDIR) | |
| 25 | modemask a mask specifying mode bits that must *not* be set | |
| 26 | owners NULL or a list of of allowable uids, count in the first item | |
| 27 | owngroups NULL or a list of allowable gids, count in the first item | |
| 28 | type name of lookup type for putting in error message | |
| 29 | errmsg where to put an error message | |
| 30 | ||
| 31 | Returns: -1 stat() or fstat() failed | |
| 32 | 0 OK | |
| 33 | +1 something didn't match | |
| 34 | ||
| 35 | Side effect: sets errno to ERRNO_BADUGID, ERRNO_NOTREGULAR or ERRNO_BADMODE for | |
| 36 | bad uid/gid, not a regular file, or bad mode; otherwise leaves it | |
| 37 | to what fstat set it to. | |
| 38 | */ | |
| 39 | ||
| 40 | int | |
| 41 | lf_check_file(int fd, uschar *filename, int s_type, int modemask, uid_t *owners, | |
| 1ba28e2b | 42 | gid_t *owngroups, const char *type, uschar **errmsg) |
| 0756eb3c PH |
43 | { |
| 44 | int i; | |
| 45 | struct stat statbuf; | |
| 46 | ||
| 47 | if ((fd >= 0 && fstat(fd, &statbuf) != 0) || | |
| 48 | (fd < 0 && Ustat(filename, &statbuf) != 0)) | |
| 49 | { | |
| 50 | int save_errno = errno; | |
| 51 | *errmsg = string_sprintf("%s: stat failed", filename); | |
| 52 | errno = save_errno; | |
| 53 | return -1; | |
| 54 | } | |
| 55 | ||
| 56 | if ((statbuf.st_mode & S_IFMT) != s_type) | |
| 57 | { | |
| 58 | if (s_type == S_IFREG) | |
| 59 | { | |
| 60 | *errmsg = string_sprintf("%s is not a regular file (%s lookup)", | |
| 61 | filename, type); | |
| 62 | errno = ERRNO_NOTREGULAR; | |
| 63 | } | |
| 64 | else | |
| 65 | { | |
| 66 | *errmsg = string_sprintf("%s is not a directory (%s lookup)", | |
| 67 | filename, type); | |
| 68 | errno = ERRNO_NOTDIRECTORY; | |
| 69 | } | |
| 70 | return +1; | |
| 71 | } | |
| 72 | ||
| 73 | if ((statbuf.st_mode & modemask) != 0) | |
| 74 | { | |
| 75 | *errmsg = string_sprintf("%s (%s lookup): file mode %.4o should not contain " | |
| 76 | "%.4o", filename, type, statbuf.st_mode & 07777, | |
| 77 | statbuf.st_mode & modemask); | |
| 78 | errno = ERRNO_BADMODE; | |
| 79 | return +1; | |
| 80 | } | |
| 81 | ||
| 82 | if (owners != NULL) | |
| 83 | { | |
| 84 | BOOL uid_ok = FALSE; | |
| 85 | for (i = 1; i <= (int)owners[0]; i++) | |
| 86 | if (owners[i] == statbuf.st_uid) { uid_ok = TRUE; break; } | |
| 87 | if (!uid_ok) | |
| 88 | { | |
| 89 | *errmsg = string_sprintf("%s (%s lookup): file has wrong owner", filename, | |
| 90 | type); | |
| 91 | errno = ERRNO_BADUGID; | |
| 92 | return +1; | |
| 93 | } | |
| 94 | } | |
| 95 | ||
| 96 | if (owngroups != NULL) | |
| 97 | { | |
| 98 | BOOL gid_ok = FALSE; | |
| 99 | for (i = 1; i <= (int)owngroups[0]; i++) | |
| 100 | if (owngroups[i] == statbuf.st_gid) { gid_ok = TRUE; break; } | |
| 101 | if (!gid_ok) | |
| 102 | { | |
| 103 | *errmsg = string_sprintf("%s (%s lookup): file has wrong group", filename, | |
| 104 | type); | |
| 105 | errno = ERRNO_BADUGID; | |
| 106 | return +1; | |
| 107 | } | |
| 108 | } | |
| 109 | ||
| 110 | return 0; | |
| 111 | } | |
| 112 | ||
| 113 | /* End of lf_check_file.c */ |