From 4ac04d76dc0fffe48313d6a16b4ca9b44c135818 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Fri, 26 Sep 2008 12:39:13 -0400 Subject: [PATCH] rpc.tatd: refactor check to see if call is from loopback address Refactor common logic to check if SM_FOO request is from loopback address. We'll have to do something about this for IPv6. On IPv6-capable systems, there will be only one AF_INET6 listener. The loopback caller will get either an IPv6 loopback address, or a mapped IPv4 loopback -- either way this will be an AF_INET6 address. Signed-off-by: Chuck Lever Acked-by: Neil Brown Signed-off-by: Steve Dickson --- utils/statd/monitor.c | 82 +++++++++++++++++++------------------------ 1 file changed, 36 insertions(+), 46 deletions(-) diff --git a/utils/statd/monitor.c b/utils/statd/monitor.c index eadc434..5d4aa49 100644 --- a/utils/statd/monitor.c +++ b/utils/statd/monitor.c @@ -29,6 +29,36 @@ notify_list * rtnl = NULL; /* Run-time notify list. */ #define LINELEN (4*(8+1)+SM_PRIV_SIZE*2+1) +#ifdef RESTRICTED_STATD +/* + * Reject requests from non-loopback addresses in order + * to prevent attack described in CERT CA-99.05. + */ +static int +caller_is_localhost(struct svc_req *rqstp) +{ + struct in_addr caller; + + caller = svc_getcaller(rqstp->rq_xprt)->sin_addr; + if (caller.s_addr != htonl(INADDR_LOOPBACK)) { + note(N_WARNING, + "Call to statd from non-local host %s", + inet_ntoa(caller)); + return 0; + } + return 1; +} +#else /* RESTRICTED_STATD */ +/* + * No restrictions for remote callers. + */ +static int +caller_is_localhost(struct svc_req *rqstp) +{ + return 1; +} +#endif /* RESTRICTED_STATD */ + /* * Services SM_MON requests. */ @@ -45,31 +75,19 @@ sm_mon_1_svc(struct mon *argp, struct svc_req *rqstp) notify_list *clnt; struct in_addr my_addr; char *dnsname; -#ifdef RESTRICTED_STATD - struct in_addr caller; -#endif struct hostent *hostinfo = NULL; /* Assume that we'll fail. */ result.res_stat = STAT_FAIL; result.state = -1; /* State is undefined for STAT_FAIL. */ - /* Restrict access to statd. - * In the light of CERT CA-99.05, we tighten access to - * statd. --okir - */ #ifdef RESTRICTED_STATD - /* 1. Reject anyone not calling from 127.0.0.1. + /* 1. Reject any remote callers. * Ignore the my_name specified by the caller, and * use "127.0.0.1" instead. */ - caller = svc_getcaller(rqstp->rq_xprt)->sin_addr; - if (caller.s_addr != htonl(INADDR_LOOPBACK)) { - note(N_WARNING, - "Call to statd from non-local host %s", - inet_ntoa(caller)); + if (!caller_is_localhost(rqstp)) goto failure; - } my_addr.s_addr = htonl(INADDR_LOOPBACK); /* 2. Reject any registrations for non-lockd services. @@ -329,25 +347,12 @@ sm_unmon_1_svc(struct mon_id *argp, struct svc_req *rqstp) *my_name = argp->my_id.my_name; struct my_id *id = &argp->my_id; char *cp; -#ifdef RESTRICTED_STATD - struct in_addr caller; -#endif result.state = MY_STATE; -#ifdef RESTRICTED_STATD - /* 1. Reject anyone not calling from 127.0.0.1. - * Ignore the my_name specified by the caller, and - * use "127.0.0.1" instead. - */ - caller = svc_getcaller(rqstp->rq_xprt)->sin_addr; - if (caller.s_addr != htonl(INADDR_LOOPBACK)) { - note(N_WARNING, - "Call to statd from non-local host %s", - inet_ntoa(caller)); + if (!caller_is_localhost(rqstp)) goto failure; - } -#endif + /* my_name must not have white space */ for (cp=my_name ; *cp ; cp++) if (*cp == ' ' || *cp == '\t' || *cp == '\r' || *cp == '\n') @@ -388,9 +393,7 @@ sm_unmon_1_svc(struct mon_id *argp, struct svc_req *rqstp) clnt = NL_NEXT(clnt); } -#ifdef RESTRICTED_STATD failure: -#endif note(N_WARNING, "Received erroneous SM_UNMON request from %s for %s", my_name, mon_name); return (&result); @@ -404,21 +407,9 @@ sm_unmon_all_1_svc(struct my_id *argp, struct svc_req *rqstp) static sm_stat result; notify_list *clnt; char *my_name = argp->my_name; -#ifdef RESTRICTED_STATD - struct in_addr caller; - /* 1. Reject anyone not calling from 127.0.0.1. - * Ignore the my_name specified by the caller, and - * use "127.0.0.1" instead. - */ - caller = svc_getcaller(rqstp->rq_xprt)->sin_addr; - if (caller.s_addr != htonl(INADDR_LOOPBACK)) { - note(N_WARNING, - "Call to statd from non-local host %s", - inet_ntoa(caller)); + if (!caller_is_localhost(rqstp)) goto failure; - } -#endif result.state = MY_STATE; @@ -457,8 +448,7 @@ sm_unmon_all_1_svc(struct my_id *argp, struct svc_req *rqstp) dprintf(N_DEBUG, "SM_UNMON_ALL request from %s with no " "SM_MON requests from it.", my_name); } -#ifdef RESTRICTED_STATD + failure: -#endif return (&result); } -- 2.39.2