diff options
Diffstat (limited to 'misc.c')
-rw-r--r-- | misc.c | 58 |
1 files changed, 53 insertions, 5 deletions
@@ -55,8 +55,9 @@ | |||
55 | #include <netdb.h> | 55 | #include <netdb.h> |
56 | #ifdef HAVE_PATHS_H | 56 | #ifdef HAVE_PATHS_H |
57 | # include <paths.h> | 57 | # include <paths.h> |
58 | #include <pwd.h> | ||
59 | #endif | 58 | #endif |
59 | #include <pwd.h> | ||
60 | #include <grp.h> | ||
60 | #ifdef SSH_TUN_OPENBSD | 61 | #ifdef SSH_TUN_OPENBSD |
61 | #include <net/if.h> | 62 | #include <net/if.h> |
62 | #endif | 63 | #endif |
@@ -1272,6 +1273,55 @@ percent_dollar_expand(const char *string, ...) | |||
1272 | } | 1273 | } |
1273 | 1274 | ||
1274 | int | 1275 | int |
1276 | secure_permissions(struct stat *st, uid_t uid) | ||
1277 | { | ||
1278 | if (!platform_sys_dir_uid(st->st_uid) && st->st_uid != uid) | ||
1279 | return 0; | ||
1280 | if ((st->st_mode & 002) != 0) | ||
1281 | return 0; | ||
1282 | if ((st->st_mode & 020) != 0) { | ||
1283 | /* If the file is group-writable, the group in question must | ||
1284 | * have exactly one member, namely the file's owner. | ||
1285 | * (Zero-member groups are typically used by setgid | ||
1286 | * binaries, and are unlikely to be suitable.) | ||
1287 | */ | ||
1288 | struct passwd *pw; | ||
1289 | struct group *gr; | ||
1290 | int members = 0; | ||
1291 | |||
1292 | gr = getgrgid(st->st_gid); | ||
1293 | if (!gr) | ||
1294 | return 0; | ||
1295 | |||
1296 | /* Check primary group memberships. */ | ||
1297 | while ((pw = getpwent()) != NULL) { | ||
1298 | if (pw->pw_gid == gr->gr_gid) { | ||
1299 | ++members; | ||
1300 | if (pw->pw_uid != uid) | ||
1301 | return 0; | ||
1302 | } | ||
1303 | } | ||
1304 | endpwent(); | ||
1305 | |||
1306 | pw = getpwuid(st->st_uid); | ||
1307 | if (!pw) | ||
1308 | return 0; | ||
1309 | |||
1310 | /* Check supplementary group memberships. */ | ||
1311 | if (gr->gr_mem[0]) { | ||
1312 | ++members; | ||
1313 | if (strcmp(pw->pw_name, gr->gr_mem[0]) || | ||
1314 | gr->gr_mem[1]) | ||
1315 | return 0; | ||
1316 | } | ||
1317 | |||
1318 | if (!members) | ||
1319 | return 0; | ||
1320 | } | ||
1321 | return 1; | ||
1322 | } | ||
1323 | |||
1324 | int | ||
1275 | tun_open(int tun, int mode, char **ifname) | 1325 | tun_open(int tun, int mode, char **ifname) |
1276 | { | 1326 | { |
1277 | #if defined(CUSTOM_SYS_TUN_OPEN) | 1327 | #if defined(CUSTOM_SYS_TUN_OPEN) |
@@ -2056,8 +2106,7 @@ safe_path(const char *name, struct stat *stp, const char *pw_dir, | |||
2056 | snprintf(err, errlen, "%s is not a regular file", buf); | 2106 | snprintf(err, errlen, "%s is not a regular file", buf); |
2057 | return -1; | 2107 | return -1; |
2058 | } | 2108 | } |
2059 | if ((!platform_sys_dir_uid(stp->st_uid) && stp->st_uid != uid) || | 2109 | if (!secure_permissions(stp, uid)) { |
2060 | (stp->st_mode & 022) != 0) { | ||
2061 | snprintf(err, errlen, "bad ownership or modes for file %s", | 2110 | snprintf(err, errlen, "bad ownership or modes for file %s", |
2062 | buf); | 2111 | buf); |
2063 | return -1; | 2112 | return -1; |
@@ -2072,8 +2121,7 @@ safe_path(const char *name, struct stat *stp, const char *pw_dir, | |||
2072 | strlcpy(buf, cp, sizeof(buf)); | 2121 | strlcpy(buf, cp, sizeof(buf)); |
2073 | 2122 | ||
2074 | if (stat(buf, &st) == -1 || | 2123 | if (stat(buf, &st) == -1 || |
2075 | (!platform_sys_dir_uid(st.st_uid) && st.st_uid != uid) || | 2124 | !secure_permissions(&st, uid)) { |
2076 | (st.st_mode & 022) != 0) { | ||
2077 | snprintf(err, errlen, | 2125 | snprintf(err, errlen, |
2078 | "bad ownership or modes for directory %s", buf); | 2126 | "bad ownership or modes for directory %s", buf); |
2079 | return -1; | 2127 | return -1; |