lib: updates to zapi_route

This patch introduces the following changes to the zapi_route structure
and associated code:
* Use a fixed-size array to store the nexthops instead of a pointer. This
  makes the zapi_route() function much easier to use when we have multiple
  nexthops to send. It's also much more efficient to put everything on
  the stack rather than allocating an array in the heap every time we
  need to send a route to zebra;

* Use the new 'zapi_nexthop' structure. This will allow the client daemons
  to send labeled routes without having to allocate memory for the labels
  (the 'nexthop' structure was designed to be memory efficient and doesn't
  have room for MPLS labels, only a pointer). Also, 'zapi_nexthop' is more
  compact and more clean from an API perspective;

* Embed the route prefix inside the zapi_route structure. Since the
  route's prefix is sent along with its nexthops and attributes, it makes
  sense to pack everything inside the same structure.

Signed-off-by: Renato Westphal <renato@opensourcerouting.org>

diff --git a/babeld/kernel.c b/babeld/kernel.c
index 26860f3bae6ede6fa59ab44ad1b4acbe1b424e88..105a7d0518867e4cabd2084b458bc8f6fb15cc34 100644 (file)
--- a/babeld/kernel.c
+++ b/babeld/kernel.c
@@ -144,15 +144,15 @@ kernel_route_v4(int add,
                 const unsigned char *gate, int ifindex, unsigned int metric)
 {
     struct zapi_route api;               /* quagga's communication system */
+    struct zapi_nexthop *api_nh;         /* next router to go - no ECMP */
     struct prefix quagga_prefix;         /* quagga's prefix */
     struct in_addr babel_prefix_addr;    /* babeld's prefix addr */
-    struct nexthop nexthop;              /* next router to go */
-    struct nexthop *nexthop_pointer = &nexthop; /* it's an array! */
+
+    api_nh = &api.nexthops[0];
 
     /* convert to be understandable by quagga */
     /* convert given addresses */
     uchar_to_inaddr(&babel_prefix_addr, pref);
-    uchar_to_inaddr(&nexthop.gate.ipv4, gate);
 
     /* make prefix structure */
     memset (&quagga_prefix, 0, sizeof(quagga_prefix));
@@ -168,6 +168,7 @@ kernel_route_v4(int add,
     api.instance = 0;
     api.safi = SAFI_UNICAST;
     api.vrf_id = VRF_DEFAULT;
+    api.prefix = quagga_prefix;
 
     SET_FLAG(api.message, ZAPI_MESSAGE_NEXTHOP);
     if(metric >= KERNEL_INFINITY) {
@@ -175,13 +176,13 @@ kernel_route_v4(int add,
         api.nexthop_num = 0;
     } else {
         api.nexthop_num = 1;
-        api.nexthop = &nexthop_pointer;
-        nexthop.ifindex = ifindex;
-        if (IPV4_ADDR_SAME (&nexthop.gate.ipv4, &quagga_prefix.u.prefix4) &&
+        api_nh->ifindex = ifindex;
+        uchar_to_inaddr(&api_nh->gate.ipv4, gate);
+        if (IPV4_ADDR_SAME (&api_nh->gate.ipv4, &quagga_prefix.u.prefix4) &&
                 quagga_prefix.prefixlen == 32) {
-            nexthop.type = NEXTHOP_TYPE_IFINDEX;
+            api_nh->type = NEXTHOP_TYPE_IFINDEX;
         } else {
-            nexthop.type = NEXTHOP_TYPE_IPV4_IFINDEX;
+            api_nh->type = NEXTHOP_TYPE_IPV4_IFINDEX;
         }
         SET_FLAG(api.message, ZAPI_MESSAGE_METRIC);
         api.metric = metric;
@@ -191,7 +192,7 @@ kernel_route_v4(int add,
            add ? "adding" : "removing" );
     return zapi_route (add ? ZEBRA_IPV4_ROUTE_ADD :
                        ZEBRA_IPV4_ROUTE_DELETE,
-                       zclient, &quagga_prefix, NULL, &api);
+                       zclient, &api);
 }
 
 static int
@@ -199,15 +200,15 @@ kernel_route_v6(int add, const unsigned char *pref, unsigned short plen,
                 const unsigned char *gate, int ifindex, unsigned int metric)
 {
     struct zapi_route api;              /* quagga's communication system */
+    struct zapi_nexthop *api_nh;        /* next router to go - no ECMP */
     struct prefix quagga_prefix;        /* quagga's prefix */
     struct in6_addr babel_prefix_addr;  /* babeld's prefix addr */
-    struct nexthop nexthop;             /* next router to go */
-    struct nexthop *nexthop_pointer = &nexthop;
+
+    api_nh = &api.nexthops[0];
 
     /* convert to be understandable by quagga */
     /* convert given addresses */
     uchar_to_in6addr(&babel_prefix_addr, pref);
-    uchar_to_in6addr(&nexthop.gate.ipv6, gate);
 
     /* make prefix structure */
     memset (&quagga_prefix, 0, sizeof(quagga_prefix));
@@ -223,6 +224,7 @@ kernel_route_v6(int add, const unsigned char *pref, unsigned short plen,
     api.instance = 0;
     api.safi = SAFI_UNICAST;
     api.vrf_id = VRF_DEFAULT;
+    api.prefix = quagga_prefix;
 
     if(metric >= KERNEL_INFINITY) {
         api.flags = ZEBRA_FLAG_REJECT;
@@ -230,10 +232,10 @@ kernel_route_v6(int add, const unsigned char *pref, unsigned short plen,
     } else {
         SET_FLAG(api.message, ZAPI_MESSAGE_NEXTHOP);
         api.nexthop_num = 1;
-        api.nexthop = &nexthop_pointer;
-        nexthop.ifindex = ifindex;
+        api_nh->ifindex = ifindex;
+        uchar_to_in6addr(&api_nh->gate.ipv6, gate);
         /* difference to IPv4: always leave the linklocal as nexthop */
-        nexthop.type = NEXTHOP_TYPE_IPV6_IFINDEX;
+        api_nh->type = NEXTHOP_TYPE_IPV6_IFINDEX;
         SET_FLAG(api.message, ZAPI_MESSAGE_METRIC);
         api.metric = metric;
     }
@@ -242,7 +244,7 @@ kernel_route_v6(int add, const unsigned char *pref, unsigned short plen,
            add ? "adding" : "removing" );
     return zapi_route (add ? ZEBRA_IPV6_ROUTE_ADD :
                        ZEBRA_IPV6_ROUTE_DELETE,
-                       zclient, &quagga_prefix, NULL, &api);
+                       zclient, &api);
 }
 
 int

diff --git a/lib/zclient.c b/lib/zclient.c
index f8bbdd85c904e2f2b9cc53a91c43dc9e008635f9..53e8569b77ecca615e31cacaf981c056c4e42c56 100644 (file)
--- a/lib/zclient.c
+++ b/lib/zclient.c
@@ -892,16 +892,12 @@ int zapi_ipv6_route(u_char cmd, struct zclient *zclient, struct prefix_ipv6 *p,
        return zclient_send_message(zclient);
 }
 
-int zapi_route(u_char cmd, struct zclient *zclient, struct prefix *p,
-              struct prefix_ipv6 *src_p, struct zapi_route *api)
+int zapi_route(u_char cmd, struct zclient *zclient, struct zapi_route *api)
 {
        int i;
        int psize;
        struct stream *s;
-
-       /* either we have !SRCPFX && src_p == NULL, or SRCPFX && src_p != NULL
-        */
-       assert(!(api->message & ZAPI_MESSAGE_SRCPFX) == !src_p);
+       struct zapi_nexthop *api_nh;
 
        /* Reset stream. */
        s = zclient->obuf;
@@ -917,69 +913,63 @@ int zapi_route(u_char cmd, struct zclient *zclient, struct prefix *p,
        stream_putw(s, api->safi);
 
        /* Put prefix information. */
-       psize = PSIZE(p->prefixlen);
-       stream_putc(s, p->prefixlen);
-       stream_write(s, (u_char *)&p->u.prefix, psize);
+       psize = PSIZE(api->prefix.prefixlen);
+       stream_putc(s, api->prefix.prefixlen);
+       stream_write(s, (u_char *)&api->prefix.u.prefix, psize);
 
        if (CHECK_FLAG(api->message, ZAPI_MESSAGE_SRCPFX)) {
-               psize = PSIZE(src_p->prefixlen);
-               stream_putc(s, src_p->prefixlen);
-               stream_write(s, (u_char *)&src_p->prefix, psize);
+               psize = PSIZE(api->src_prefix.prefixlen);
+               stream_putc(s, api->src_prefix.prefixlen);
+               stream_write(s, (u_char *)&api->src_prefix.prefix, psize);
        }
 
        /* Nexthop, ifindex, distance and metric information. */
        if (CHECK_FLAG(api->message, ZAPI_MESSAGE_NEXTHOP)) {
+               /* limit the number of nexthops if necessary */
+               if (api->nexthop_num > MULTIPATH_NUM) {
+                       char buf[PREFIX2STR_BUFFER];
+
+                       prefix2str(&api->prefix, buf, sizeof(buf));
+                       zlog_warn(
+                               "%s: prefix %s: encoding %u nexthops out of %u",
+                               __func__, buf, MULTIPATH_NUM, api->nexthop_num);
+                       api->nexthop_num = MULTIPATH_NUM;
+               }
+
                stream_putc(s, api->nexthop_num);
 
                for (i = 0; i < api->nexthop_num; i++) {
-                       stream_putc(s, api->nexthop[i]->type);
-                       switch (api->nexthop[i]->type) {
+                       api_nh = &api->nexthops[i];
+
+                       stream_putc(s, api_nh->type);
+                       switch (api_nh->type) {
                        case NEXTHOP_TYPE_BLACKHOLE:
                                break;
                        case NEXTHOP_TYPE_IPV4:
-                               stream_put_in_addr(s,
-                                                  &api->nexthop[i]->gate.ipv4);
-
-                               /* For labeled-unicast, each nexthop is followed
-                                * by label. */
-                               if (CHECK_FLAG(api->message,
-                                              ZAPI_MESSAGE_LABEL))
-                                       stream_putl(
-                                               s,
-                                               api->nexthop[i]
-                                                       ->nh_label->label[0]);
+                               stream_put_in_addr(s, &api_nh->gate.ipv4);
                                break;
                        case NEXTHOP_TYPE_IPV4_IFINDEX:
-                               stream_put_in_addr(s,
-                                                  &api->nexthop[i]->gate.ipv4);
-                               stream_putl(s, api->nexthop[i]->ifindex);
+                               stream_put_in_addr(s, &api_nh->gate.ipv4);
+                               stream_putl(s, api_nh->ifindex);
                                break;
                        case NEXTHOP_TYPE_IFINDEX:
-                               stream_putl(s, api->nexthop[i]->ifindex);
+                               stream_putl(s, api_nh->ifindex);
                                break;
                        case NEXTHOP_TYPE_IPV6:
-                               stream_write(
-                                       s,
-                                       (u_char *)&api->nexthop[i]->gate.ipv6,
-                                       16);
-
-                               /* For labeled-unicast, each nexthop is followed
-                                * by label. */
-                               if (CHECK_FLAG(api->message,
-                                              ZAPI_MESSAGE_LABEL))
-                                       stream_putl(
-                                               s,
-                                               api->nexthop[i]
-                                                       ->nh_label->label[0]);
+                               stream_write(s, (u_char *)&api_nh->gate.ipv6,
+                                            16);
                                break;
                        case NEXTHOP_TYPE_IPV6_IFINDEX:
-                               stream_write(
-                                       s,
-                                       (u_char *)&api->nexthop[i]->gate.ipv6,
-                                       16);
-                               stream_putl(s, api->nexthop[i]->ifindex);
+                               stream_write(s, (u_char *)&api_nh->gate.ipv6,
+                                            16);
+                               stream_putl(s, api_nh->ifindex);
                                break;
                        }
+
+                       /* For labeled-unicast, each nexthop is followed
+                        * by label. */
+                       if (CHECK_FLAG(api->message, ZAPI_MESSAGE_LABEL))
+                               stream_putl(s, api_nh->label);
                }
        }
 

diff --git a/lib/zclient.h b/lib/zclient.h
index ddd9655443a428f5b35d63c56e18d3da101e7979..92aeabb07f732d669c08d133c8924980a40fbe77 100644 (file)
--- a/lib/zclient.h
+++ b/lib/zclient.h
@@ -224,6 +224,13 @@ struct zserv_header {
        uint16_t command;
 };
 
+struct zapi_nexthop {
+       enum nexthop_types_t type;
+       ifindex_t ifindex;
+       union g_addr gate;
+       mpls_label_t label;
+};
+
 struct zapi_route {
        u_char type;
        u_short instance;
@@ -234,8 +241,11 @@ struct zapi_route {
 
        safi_t safi;
 
+       struct prefix prefix;
+       struct prefix_ipv6 src_prefix;
+
        u_char nexthop_num;
-       struct nexthop **nexthop;
+       struct zapi_nexthop nexthops[MULTIPATH_NUM];
 
        u_char distance;
 
@@ -416,7 +426,7 @@ extern int zapi_ipv6_route(u_char cmd, struct zclient *zclient,
 extern int zapi_ipv4_route_ipv6_nexthop(u_char, struct zclient *,
                                        struct prefix_ipv4 *,
                                        struct zapi_ipv6 *);
-extern int zapi_route(u_char cmd, struct zclient *zclient, struct prefix *p,
-                     struct prefix_ipv6 *src_p, struct zapi_route *api);
+extern int zapi_route(u_char cmd, struct zclient *zclient,
+                     struct zapi_route *api);
 
 #endif /* _ZEBRA_ZCLIENT_H */