Adding upstream version 9.1.upstream/9.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 301 insertions, 0 deletions

diff --git a/babeld/resend.c b/babeld/resend.c
new file mode 100644
index 0000000..254faac
--- /dev/null
+++ b/babeld/resend.c
@@ -0,0 +1,301 @@
+// SPDX-License-Identifier: MIT
+/*
+Copyright (c) 2007, 2008 by Juliusz Chroboczek
+*/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <sys/time.h>
+#include <time.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include <zebra.h>
+#include "if.h"
+
+#include "babel_main.h"
+#include "babeld.h"
+#include "util.h"
+#include "neighbour.h"
+#include "resend.h"
+#include "message.h"
+#include "babel_interface.h"
+
+struct timeval resend_time = {0, 0};
+struct resend *to_resend = NULL;
+
+static int
+resend_match(struct resend *resend,
+             int kind, const unsigned char *prefix, unsigned char plen)
+{
+    return (resend->kind == kind &&
+            resend->plen == plen && memcmp(resend->prefix, prefix, 16) == 0);
+}
+
+/* This is called by neigh.c when a neighbour is flushed */
+
+void
+flush_resends(struct neighbour *neigh)
+{
+    /* Nothing for now */
+}
+
+static struct resend *
+find_resend(int kind, const unsigned char *prefix, unsigned char plen,
+             struct resend **previous_return)
+{
+    struct resend *current, *previous;
+
+    previous = NULL;
+    current = to_resend;
+    while(current) {
+        if(resend_match(current, kind, prefix, plen)) {
+            if(previous_return)
+                *previous_return = previous;
+            return current;
+        }
+        previous = current;
+        current = current->next;
+    }
+
+    return NULL;
+}
+
+struct resend *
+find_request(const unsigned char *prefix, unsigned char plen,
+             struct resend **previous_return)
+{
+    return find_resend(RESEND_REQUEST, prefix, plen, previous_return);
+}
+
+int
+record_resend(int kind, const unsigned char *prefix, unsigned char plen,
+              unsigned short seqno, const unsigned char *id,
+              struct interface *ifp, int delay)
+{
+    struct resend *resend;
+    unsigned int ifindex = ifp ? ifp->ifindex : 0;
+
+    if((kind == RESEND_REQUEST &&
+        input_filter(NULL, prefix, plen, NULL, ifindex) >= INFINITY) ||
+       (kind == RESEND_UPDATE &&
+        output_filter(NULL, prefix, plen, ifindex) >= INFINITY))
+        return 0;
+
+    if(delay >= 0xFFFF)
+        delay = 0xFFFF;
+
+    resend = find_resend(kind, prefix, plen, NULL);
+    if(resend) {
+        if(resend->delay && delay)
+            resend->delay = MIN(resend->delay, delay);
+        else if(delay)
+            resend->delay = delay;
+        resend->time = babel_now;
+        resend->max = RESEND_MAX;
+        if(id && memcmp(resend->id, id, 8) == 0 &&
+           seqno_compare(resend->seqno, seqno) > 0) {
+            return 0;
+        }
+        if(id)
+            memcpy(resend->id, id, 8);
+        else
+            memset(resend->id, 0, 8);
+        resend->seqno = seqno;
+        if(resend->ifp != ifp)
+            resend->ifp = NULL;
+    } else {
+        resend = malloc(sizeof(struct resend));
+        if(resend == NULL)
+            return -1;
+        resend->kind = kind;
+        resend->max = RESEND_MAX;
+        resend->delay = delay;
+        memcpy(resend->prefix, prefix, 16);
+        resend->plen = plen;
+        resend->seqno = seqno;
+        if(id)
+            memcpy(resend->id, id, 8);
+        else
+            memset(resend->id, 0, 8);
+        resend->ifp = ifp;
+        resend->time = babel_now;
+        resend->next = to_resend;
+        to_resend = resend;
+    }
+
+    if(resend->delay) {
+        struct timeval timeout;
+        timeval_add_msec(&timeout, &resend->time, resend->delay);
+        timeval_min(&resend_time, &timeout);
+    }
+    return 1;
+}
+
+static int
+resend_expired(struct resend *resend)
+{
+    switch(resend->kind) {
+    case RESEND_REQUEST:
+        return timeval_minus_msec(&babel_now, &resend->time) >= REQUEST_TIMEOUT;
+    default:
+        return resend->max <= 0;
+    }
+}
+
+int
+unsatisfied_request(const unsigned char *prefix, unsigned char plen,
+                    unsigned short seqno, const unsigned char *id)
+{
+    struct resend *request;
+
+    request = find_request(prefix, plen, NULL);
+    if(request == NULL || resend_expired(request))
+        return 0;
+
+    if(memcmp(request->id, id, 8) != 0 ||
+       seqno_compare(request->seqno, seqno) <= 0)
+        return 1;
+
+    return 0;
+}
+
+/* Determine whether a given request should be forwarded. */
+int
+request_redundant(struct interface *ifp,
+                  const unsigned char *prefix, unsigned char plen,
+                  unsigned short seqno, const unsigned char *id)
+{
+    struct resend *request;
+
+    request = find_request(prefix, plen, NULL);
+    if(request == NULL || resend_expired(request))
+        return 0;
+
+    if(memcmp(request->id, id, 8) == 0 &&
+       seqno_compare(request->seqno, seqno) > 0)
+        return 0;
+
+    if(request->ifp != NULL && request->ifp != ifp)
+        return 0;
+
+    if(request->max > 0)
+        /* Will be resent. */
+        return 1;
+
+    if(timeval_minus_msec(&babel_now, &request->time) <
+       (ifp ? MIN(babel_get_if_nfo(ifp)->hello_interval, 1000) : 1000))
+        /* Fairly recent. */
+        return 1;
+
+    return 0;
+}
+
+int
+satisfy_request(const unsigned char *prefix, unsigned char plen,
+                unsigned short seqno, const unsigned char *id,
+                struct interface *ifp)
+{
+    struct resend *request, *previous;
+
+    request = find_request(prefix, plen, &previous);
+    if(request == NULL)
+        return 0;
+
+    if(ifp != NULL && request->ifp != ifp)
+        return 0;
+
+    if(memcmp(request->id, id, 8) != 0 ||
+       seqno_compare(request->seqno, seqno) <= 0) {
+        /* We cannot remove the request, as we may be walking the list right
+           now.  Mark it as expired, so that expire_resend will remove it. */
+        request->max = 0;
+        request->time.tv_sec = 0;
+        recompute_resend_time();
+        return 1;
+    }
+
+    return 0;
+}
+
+void
+expire_resend(void)
+{
+    struct resend *current, *previous;
+    int recompute = 0;
+
+    previous = NULL;
+    current = to_resend;
+    while(current) {
+        if(resend_expired(current)) {
+            if(previous == NULL) {
+                to_resend = current->next;
+                free(current);
+                current = to_resend;
+            } else {
+                previous->next = current->next;
+                free(current);
+                current = previous->next;
+            }
+            recompute = 1;
+        } else {
+            previous = current;
+            current = current->next;
+        }
+    }
+    if(recompute)
+        recompute_resend_time();
+}
+
+void
+recompute_resend_time(void)
+{
+    struct resend *request;
+    struct timeval resend = {0, 0};
+
+    request = to_resend;
+    while(request) {
+        if(!resend_expired(request) && request->delay > 0 && request->max > 0) {
+            struct timeval timeout;
+            timeval_add_msec(&timeout, &request->time, request->delay);
+            timeval_min(&resend, &timeout);
+        }
+        request = request->next;
+    }
+
+    resend_time = resend;
+}
+
+void
+do_resend(void)
+{
+    struct resend *resend;
+
+    resend = to_resend;
+    while(resend) {
+        if(!resend_expired(resend) && resend->delay > 0 && resend->max > 0) {
+            struct timeval timeout;
+            timeval_add_msec(&timeout, &resend->time, resend->delay);
+            if(timeval_compare(&babel_now, &timeout) >= 0) {
+                switch(resend->kind) {
+                case RESEND_REQUEST:
+                    send_multihop_request(resend->ifp,
+                                          resend->prefix, resend->plen,
+                                          resend->seqno, resend->id, 127);
+                    break;
+                case RESEND_UPDATE:
+                    send_update(resend->ifp, 1,
+                                resend->prefix, resend->plen);
+                    break;
+                default: abort();
+                }
+                resend->delay = MIN(0xFFFF, resend->delay * 2);
+                resend->max--;
+            }
+        }
+        resend = resend->next;
+    }
+    recompute_resend_time();
+}