diff options
Diffstat (limited to 'inet/rcmd.c')
-rw-r--r-- | inet/rcmd.c | 50 |
1 files changed, 31 insertions, 19 deletions
diff --git a/inet/rcmd.c b/inet/rcmd.c index 98b3735d1f..035cb0d87d 100644 --- a/inet/rcmd.c +++ b/inet/rcmd.c @@ -809,31 +809,43 @@ __validuser2_sa(hostf, ra, ralen, luser, ruser, rhost) *p = '\0'; /* <nul> terminate username (+host?) */ /* buf -> host(?) ; user -> username(?) */ + if (*buf == '\0') + break; + if (*user == '\0') + user = luser; + + /* First check the user part. In a naive implementation we + would check the host part first, then the user. However, + if we check the user first and reject the entry we will + have saved doing any host lookups to normalize the comparison + and that likely saves several DNS queries. Therefore we + check the user first. */ + ucheck = __icheckuser (user, ruser); + + /* Either we found the user, or we didn't and this is a + negative host check. We must do the negative host lookup + in order to preserve the semantics of stopping on this line + before processing others. */ + if (ucheck != 0 || *buf == '-') { + + /* Next check host part. */ + hcheck = __checkhost_sa (ra, ralen, buf, rhost); + + /* Negative '-host user(?)' match? */ + if (hcheck < 0) + break; - /* First check host part */ - hcheck = __checkhost_sa (ra, ralen, buf, rhost); - - if (hcheck < 0) - break; - - if (hcheck) { - /* Then check user part */ - if (! (*user)) - user = luser; - - ucheck = __icheckuser (user, ruser); - - /* Positive 'host user' match? */ - if (ucheck > 0) { + /* Positive 'host user' match? */ + if (hcheck > 0 && ucheck > 0) { retval = 0; break; } - /* Negative 'host -user' match? */ - if (ucheck < 0) - break; + /* Negative 'host -user' match? */ + if (hcheck > 0 && ucheck < 0) + break; - /* Neither, go on looking for match */ + /* Neither, go on looking for match. */ } } |