Improve memory allocation parsing routes and provide a better

diagnostic if the interface for it cannot be found.

diff --git a/if-sun.c b/if-sun.c
index 9a04dcf12be95af5305ae382a893cc59dbf29a6a..152fe284fe7c38ab5d7b139c342fceefd469de89 100644 (file)
--- a/if-sun.c
+++ b/if-sun.c
@@ -265,6 +265,9 @@ if_parsert(struct dhcpcd_ctx *ctx, unsigned int level, unsigned int name,
        if ((s = open("/dev/arp", O_RDWR)) == -1)
                return -1;
 
+       /* Assume we are erroring. */
+       retval = -1;
+
        tor->PRIM_type = T_SVR4_OPTMGMT_REQ;
        tor->OPT_offset = sizeof (struct T_optmgmt_req);
        tor->OPT_length = sizeof (struct opthdr);
@@ -277,15 +280,17 @@ if_parsert(struct dhcpcd_ctx *ctx, unsigned int level, unsigned int name,
 
        ctlbuf.buf = (char *)buf;
        ctlbuf.len = tor->OPT_length + tor->OPT_offset;
-       if (putmsg(s, &ctlbuf, NULL, 0) == 1) {
-               close(s);
-               return -1;
-       }
+       if (putmsg(s, &ctlbuf, NULL, 0) == 1)
+               goto out;
 
        req = (struct opthdr *)&toa[1];
        ctlbuf.maxlen = sizeof(buf);
 
-       retval = -1;
+       /* Create a reasonable buffer to start with */
+       databuf.maxlen = BUFSIZ * 2;
+       if ((databuf.buf = malloc(databuf.maxlen)) == NULL)
+               goto out;
+
        for (;;) {
                flags = 0;
                if ((code = getmsg(s, &ctlbuf, 0, &flags)) == -1)
@@ -295,6 +300,7 @@ if_parsert(struct dhcpcd_ctx *ctx, unsigned int level, unsigned int name,
                    toa->MGMT_flags == T_SUCCESS &&
                    (size_t)ctlbuf.len >= sizeof(struct T_optmgmt_ack))
                {
+                       /* End of messages, so return success! */
                        retval = 0;
                        break;
                }
@@ -311,26 +317,33 @@ if_parsert(struct dhcpcd_ctx *ctx, unsigned int level, unsigned int name,
                        break;
                }
 
-               databuf.maxlen = req->len;
-               if ((databuf.buf = malloc(databuf.maxlen)) == NULL)
-                       break;
+               /* Try to ensure out buffer is big enough
+                * for future messages as well. */
+               if ((size_t)databuf.maxlen < req->len) {
+                       size_t newlen;
 
-               flags = 0;
-               if (getmsg(s, NULL, &databuf, &flags) == -1) {
                        free(databuf.buf);
-                       break;
+                       newlen = roundup(req->len, BUFSIZ);
+                       if ((databuf.buf = malloc(newlen)) == NULL)
+                               break;
+                       databuf.maxlen = newlen;
                }
 
+               flags = 0;
+               if (getmsg(s, NULL, &databuf, &flags) == -1)
+                       break;
+
+               /* We always have to get the data before moving onto
+                * the next item, so don't move this test higher up
+                * to avoid the buffer allocation and getmsg calls. */
                if (req->level == level && req->name == name) {
-                       if (walkrt(ctx, databuf.buf, databuf.len) == -1) {
-                               free(databuf.buf);
+                       if (walkrt(ctx, databuf.buf, req->len) == -1)
                                break;
-                       }
                }
-
-               free(databuf.buf);
        }
 
+       free(databuf.buf);
+out:
        close(s);
        return retval;
 }
@@ -448,8 +461,19 @@ if_walkrt(struct dhcpcd_ctx *ctx, char *data, size_t len)
                rt.iface = if_find(ctx->ifaces, ifname);
                if (rt.iface != NULL)
                        ipv4_handlert(ctx, RTM_ADD, &rt, 1);
-               else
-                       printf ("XX %s\n", ifname);
+               else {
+                       char destbuf[INET6_ADDRSTRLEN];
+                       char gatebuf[INET6_ADDRSTRLEN];
+                       const char *dest, *gate;
+
+                       dest = inet_ntop(AF_INET, &rt.dest,
+                           destbuf, INET6_ADDRSTRLEN);
+                       gate = inet_ntop(AF_INET, &rt.gate,
+                           gatebuf, INET6_ADDRSTRLEN);
+                       logger(ctx, LOG_ERR,
+                           "no iface (%s) for route to %s via %s",
+                           ifname, dest, gate);
+               }
        } while (++re < e);
        return 0;
 }
@@ -540,8 +564,19 @@ if_walkrt6(struct dhcpcd_ctx *ctx, char *data, size_t len)
                rt.iface = if_find(ctx->ifaces, ifname);
                if (rt.iface != NULL)
                        ipv6_handlert(ctx, RTM_ADD, &rt);
-               else
-                       printf ("XX %s\n", ifname);
+               else {
+                       char destbuf[INET6_ADDRSTRLEN];
+                       char gatebuf[INET6_ADDRSTRLEN];
+                       const char *dest, *gate;
+
+                       dest = inet_ntop(AF_INET6, &rt.dest,
+                           destbuf, INET6_ADDRSTRLEN);
+                       gate = inet_ntop(AF_INET6, &rt.gate,
+                           gatebuf, INET6_ADDRSTRLEN);
+                       logger(ctx, LOG_ERR,
+                           "no iface (%s) for route to %s via %s",
+                           ifname, dest, gate);
+               }
        } while (++re < e);
        return 0;
 }