[src/netbsd-1-4]: src/sys/net pull-up revision 1.29

[chopps <chopps%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/eee8788b75b4
branches:  netbsd-1-4
changeset: 468026:eee8788b75b4
user:      chopps <chopps%NetBSD.org@localhost>
date:      Fri Apr 02 22:41:08 1999 +0000

description:
pull-up revision 1.29

diffstat:

 sys/net/rtsock.c |  84 ++++++++++++++++++++++++++++++++++++++++++--------------
 1 files changed, 63 insertions(+), 21 deletions(-)

diffs (179 lines):

diff -r 4bb3111aa112 -r eee8788b75b4 sys/net/rtsock.c
--- a/sys/net/rtsock.c  Fri Apr 02 22:38:48 1999 +0000
+++ b/sys/net/rtsock.c  Fri Apr 02 22:41:08 1999 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: rtsock.c,v 1.28 1998/12/12 17:26:09 christos Exp $     */
+/*     $NetBSD: rtsock.c,v 1.28.2.1 1999/04/02 22:41:08 chopps Exp $   */
 
 /*
  * Copyright (c) 1988, 1991, 1993
@@ -58,12 +58,19 @@
 struct sockproto route_proto = { PF_ROUTE, };
 
 struct walkarg {
-       int     w_op, w_arg, w_given, w_needed, w_tmemsize;
-       caddr_t w_where, w_tmem;
+       int     w_op;
+       int     w_arg;
+       int     w_given;
+       int     w_needed;
+       caddr_t w_where;
+       int     w_tmemsize;
+       int     w_tmemneeded;
+       caddr_t w_tmem;
 };
 
 static struct mbuf *rt_msg1 __P((int, struct rt_addrinfo *));
-static int rt_msg2 __P((int, struct rt_addrinfo *, caddr_t, struct walkarg *));
+static int rt_msg2 __P((int, struct rt_addrinfo *, caddr_t, struct walkarg *,
+    int *));
 static void rt_xaddrs __P((caddr_t, caddr_t, struct rt_addrinfo *));
 static __inline void rt_adjustcount __P((int, int));
 
@@ -277,8 +284,8 @@
                                        ifaaddr = 0;
                            }
                        }
-                       len = rt_msg2(rtm->rtm_type, &info, (caddr_t)0,
-                           (struct walkarg *)0);
+                       (void)rt_msg2(rtm->rtm_type, &info, (caddr_t)0,
+                           (struct walkarg *)0, &len);
                        if (len > rtm->rtm_msglen) {
                                struct rt_msghdr *new_rtm;
                                R_Malloc(new_rtm, struct rt_msghdr *, len);
@@ -288,7 +295,7 @@
                                Free(rtm); rtm = new_rtm;
                        }
                        (void)rt_msg2(rtm->rtm_type, &info, (caddr_t)rtm,
-                           (struct walkarg *)0);
+                           (struct walkarg *)0, 0);
                        rtm->rtm_flags = rt->rt_flags;
                        rtm->rtm_rmx = rt->rt_rmx;
                        rtm->rtm_addrs = info.rti_addrs;
@@ -470,12 +477,26 @@
        return (m);
 }
 
+/*
+ * rt_msg2
+ *
+ *      fills 'cp' or 'w'.w_tmem with the routing socket message and
+ *             returns the length of the message in 'lenp'.
+ *
+ * if walkarg is 0, cp is expected to be 0 or a buffer large enough to hold
+ *     the message
+ * otherwise walkarg's w_needed is updated and if the user buffer is
+ *     specified and w_needed indicates space exists the information is copied
+ *     into the temp space (w_tmem). w_tmem is [re]allocated if necessary,
+ *     if the allocation fails ENOBUFS is returned.
+ */
 static int
-rt_msg2(type, rtinfo, cp, w)
+rt_msg2(type, rtinfo, cp, w, lenp)
        int type;
        register struct rt_addrinfo *rtinfo;
        caddr_t cp;
        struct walkarg *w;
+       int *lenp;
 {
        register int i;
        int len, dlen, second_time = 0;
@@ -529,8 +550,10 @@
                                cp = rw->w_tmem;
                                second_time = 1;
                                goto again;
-                       } else
-                               rw->w_where = 0;
+                       } else {
+                               rw->w_tmemneeded = len;
+                               return (ENOBUFS);
+                       }
                }
        }
        if (cp) {
@@ -540,7 +563,9 @@
                rtm->rtm_type = type;
                rtm->rtm_msglen = len;
        }
-       return (len);
+       if (lenp)
+               *lenp = len;
+       return (0);
 }
 
 /*
@@ -687,8 +712,9 @@
                if (rt->rt_ifp->if_flags & IFF_POINTOPOINT)
                        brdaddr = rt->rt_ifa->ifa_dstaddr;
        }
-       size = rt_msg2(RTM_GET, &info, 0, w);
-       if (w->w_where && w->w_tmem) {
+       if ((error = rt_msg2(RTM_GET, &info, 0, w, &size)))
+               return (error);
+       if (w->w_where && w->w_tmem && w->w_needed <= 0) {
                register struct rt_msghdr *rtm = (struct rt_msghdr *)w->w_tmem;
 
                rtm->rtm_flags = rt->rt_flags;
@@ -721,9 +747,10 @@
                        continue;
                ifa = ifp->if_addrlist.tqh_first;
                ifpaddr = ifa->ifa_addr;
-               len = rt_msg2(RTM_IFINFO, &info, (caddr_t)0, w);
+               if ((error = rt_msg2(RTM_IFINFO, &info, (caddr_t)0, w, &len)))
+                       return (error);
                ifpaddr = 0;
-               if (w->w_where && w->w_tmem) {
+               if (w->w_where && w->w_tmem && w->w_needed <= 0) {
                        register struct if_msghdr *ifm;
 
                        ifm = (struct if_msghdr *)w->w_tmem;
@@ -742,8 +769,9 @@
                        ifaaddr = ifa->ifa_addr;
                        netmask = ifa->ifa_netmask;
                        brdaddr = ifa->ifa_dstaddr;
-                       len = rt_msg2(RTM_NEWADDR, &info, 0, w);
-                       if (w->w_where && w->w_tmem) {
+                       if ((error = rt_msg2(RTM_NEWADDR, &info, 0, w, &len)))
+                               return (error);
+                       if (w->w_where && w->w_tmem && w->w_needed <= 0) {
                                register struct ifa_msghdr *ifam;
 
                                ifam = (struct ifa_msghdr *)w->w_tmem;
@@ -781,12 +809,21 @@
        if (namelen != 3)
                return (EINVAL);
        af = name[0];
-       Bzero(&w, sizeof(w));
-       w.w_where = where;
+       w.w_tmemneeded = 0;
+       w.w_tmemsize = 0;
+       w.w_tmem = NULL;
+again:
+       /* we may return here if a later [re]alloc of the t_mem buffer fails */
+       if (w.w_tmemneeded) {
+               w.w_tmem = (caddr_t) malloc(w.w_tmemneeded, M_RTABLE, M_WAITOK);
+               w.w_tmemsize = w.w_tmemneeded;
+               w.w_tmemneeded = 0;
+       }
+       w.w_op = name[1];
+       w.w_arg = name[2];
        w.w_given = *given;
        w.w_needed = 0 - w.w_given;
-       w.w_op = name[1];
-       w.w_arg = name[2];
+       w.w_where = where;
 
        s = splsoftnet();
        switch (w.w_op) {
@@ -804,6 +841,11 @@
                error = sysctl_iflist(af, &w);
        }
        splx(s);
+
+       /* check to see if we couldn't allocate memory with NOWAIT */
+       if (error == ENOBUFS && w.w_tmem == 0 && w.w_tmemneeded)
+               goto again;
+
        if (w.w_tmem)
                free(w.w_tmem, M_RTABLE);
        w.w_needed += w.w_given;