Ejemplo n.º 1
0
int
ccnl_ccnb_forwarder(struct ccnl_relay_s *relay, struct ccnl_face_s *from,
		    unsigned char **data, int *datalen)
{
    int rc= -1, scope=3, aok=3, minsfx=0, maxsfx=CCNL_MAX_NAME_COMP, contlen;
    struct ccnl_buf_s *buf = 0, *nonce=0, *ppkd=0;
    struct ccnl_interest_s *i = 0;
    struct ccnl_content_s *c = 0;
    struct ccnl_prefix_s *p = 0;
    unsigned char *content = 0;
    DEBUGMSG(99, "ccnl/ccnb forwarder (%d bytes left)\n", *datalen);

    buf = ccnl_ccnb_extract(data, datalen, &scope, &aok, &minsfx,
			    &maxsfx, &p, &nonce, &ppkd, &content, &contlen);
    if (!buf) {
	    DEBUGMSG(6, "  parsing error or no prefix\n"); goto Done;
    }
    if (nonce && ccnl_nonce_find_or_append(relay, nonce)) {
	DEBUGMSG(6, "  dropped because of duplicate nonce\n"); goto Skip;
    }
    if (buf->data[0] == 0x01 && buf->data[1] == 0xd2) { // interest
	DEBUGMSG(6, "  interest=<%s>\n", ccnl_prefix_to_path(p));
	ccnl_print_stats(relay, STAT_RCV_I); //log count recv_interest
	if (p->compcnt > 0 && p->comp[0][0] == (unsigned char) 0xc1) goto Skip;
	if (p->compcnt == 4 && !memcmp(p->comp[0], "ccnx", 4)) {
	    rc = ccnl_mgmt(relay, buf, p, from); goto Done;
	}
	// CONFORM: Step 1:
	if ( aok & 0x01 ) { // honor "answer-from-existing-content-store" flag
	    for (c = relay->contents; c; c = c->next) {
		if (c->suite != CCNL_SUITE_CCNB) continue;
		if (!ccnl_i_prefixof_c(p, minsfx, maxsfx, c)) continue;
		if (ppkd && !buf_equal(ppkd, c->details.ccnb.ppkd)) continue;
		// FIXME: should check stale bit in aok here
		DEBUGMSG(7, "  matching content for interest, content %p\n", (void *) c);
		ccnl_print_stats(relay, STAT_SND_C); //log sent_c
		if (from->ifndx >= 0)
		    ccnl_face_enqueue(relay, from, buf_dup(c->pkt));
		else
		    ccnl_app_RX(relay, c);
		goto Skip;
	    }
	}
	// CONFORM: Step 2: check whether interest is already known
	for (i = relay->pit; i; i = i->next) {
	    if (i->suite == CCNL_SUITE_CCNB &&
		!ccnl_prefix_cmp(i->prefix, NULL, p, CMP_EXACT) &&
		i->details.ccnb.minsuffix == minsfx &&
		i->details.ccnb.maxsuffix == maxsfx && 
		((!ppkd && !i->details.ccnb.ppkd) ||
		   buf_equal(ppkd, i->details.ccnb.ppkd)) )
		break;
	}
	if (!i) { // this is a new/unknown I request: create and propagate
	    i = ccnl_interest_new(relay, from, CCNL_SUITE_CCNB,
				  &buf, &p, minsfx, maxsfx);
	    if (ppkd)
		i->details.ccnb.ppkd = ppkd, ppkd = NULL;
	    if (i) { // CONFORM: Step 3 (and 4)
		DEBUGMSG(7, "  created new interest entry %p\n", (void *) i);
		if (scope > 2)
		    ccnl_interest_propagate(relay, i);
	    }
	} else if (scope > 2 && (from->flags & CCNL_FACE_FLAGS_FWDALLI)) {
	    DEBUGMSG(7, "  old interest, nevertheless propagated %p\n", (void *) i);
	    ccnl_interest_propagate(relay, i);
	}
	if (i) { // store the I request, for the incoming face (Step 3)
	    DEBUGMSG(7, "  appending interest entry %p\n", (void *) i);
	    ccnl_interest_append_pending(i, from);
	}
    } else { // content
	DEBUGMSG(6, "  content=<%s>\n", ccnl_prefix_to_path(p));
	ccnl_print_stats(relay, STAT_RCV_C); //log count recv_content
        
#ifdef USE_SIGNATURES
        if (p->compcnt == 2 && !memcmp(p->comp[0], "ccnx", 4)
                && !memcmp(p->comp[1], "crypto", 6) &&
                from == relay->crypto_face) {
	    rc = ccnl_crypto(relay, buf, p, from); goto Done;
	}
#endif /*USE_SIGNATURES*/
        
        // CONFORM: Step 1:
	for (c = relay->contents; c; c = c->next)
	    if (buf_equal(c->pkt, buf)) goto Skip; // content is dup
	c = ccnl_content_new(relay, CCNL_SUITE_CCNB,
			     &buf, &p, &ppkd, content, contlen);
	if (c) { // CONFORM: Step 2 (and 3)
	    if (!ccnl_content_serve_pending(relay, c)) { // unsolicited content
		// CONFORM: "A node MUST NOT forward unsolicited data [...]"
		DEBUGMSG(7, "  removed because no matching interest\n");
		free_content(c);
		goto Skip;
	    }
	    if (relay->max_cache_entries != 0) { // it's set to -1 or a limit
		DEBUGMSG(7, "  adding content to cache\n");
		ccnl_content_add2cache(relay, c);
	    } else {
		DEBUGMSG(7, "  content not added to cache\n");
		free_content(c);
	    }
	}
    }
Skip:
    rc = 0;
Done:
    free_prefix(p);
    free_3ptr_list(buf, nonce, ppkd);
    return rc;
}
Ejemplo n.º 2
0
int ccnl_core_RX_i_or_c(struct ccnl_relay_s *relay, struct ccnl_face_s *from,
                        unsigned char **data, int *datalen)
{
    int rc = -1, scope = 3, aok = 3, minsfx = 0, maxsfx = CCNL_MAX_NAME_COMP,
        contlen;
    struct ccnl_buf_s *buf = 0, *nonce = 0, *ppkd = 0;
    struct ccnl_interest_s *i = 0;
    struct ccnl_content_s *c = 0;
    struct ccnl_prefix_s *p = 0;
    unsigned char *content = 0;
    DEBUGMSG(1, "ccnl_core_RX_i_or_c: (%d bytes left)\n", *datalen);

    buf = ccnl_extract_prefix_nonce_ppkd(data, datalen, &scope, &aok, &minsfx,
                                         &maxsfx, &p, &nonce, &ppkd, &content, &contlen);

    if (!buf) {
        DEBUGMSG(6, "  parsing error or no prefix\n");
        goto Done;
    }

    if (nonce && ccnl_nonce_find_or_append(relay, nonce)) {
        DEBUGMSG(6, "  dropped because of duplicate nonce\n");
        goto Skip;
    }

    if (buf->data[0] == 0x01 && buf->data[1] == 0xd2) { // interest
        DEBUGMSG(1, "ccnl_core_RX_i_or_c: interest=<%s>\n", ccnl_prefix_to_path(p));
        from->stat.received_interest++;

        if (p->compcnt > 0 && p->comp[0][0] == (unsigned char) 0xc1) {
            goto Skip;
        }

        if (p->compcnt == 4 && !memcmp(p->comp[0], "ccnx", 4)) {
            DEBUGMSG(1, "it's a mgnt msg!\n");
            rc = ccnl_mgmt(relay, buf, p, from);
            DEBUGMSG(1, "mgnt processing done!\n");
            goto Done;
        }

        // CONFORM: Step 1:
        if (aok & 0x01) { // honor "answer-from-existing-content-store" flag
            for (c = relay->contents; c; c = c->next) {
                if (!ccnl_i_prefixof_c(p, ppkd, minsfx, maxsfx, c)) {
                    continue;
                }

                // FIXME: should check stale bit in aok here
                DEBUGMSG(7, "  matching content for interest, content %p\n",
                         (void *) c);
                from->stat.send_content[c->served_cnt % CCNL_MAX_CONTENT_SERVED_STAT]++;
                c->served_cnt++;

                if (from->ifndx >= 0) {
                    ccnl_face_enqueue(relay, from, buf_dup(c->pkt));
                }

                goto Skip;
            }
        }

        // CONFORM: Step 2: check whether interest is already known
        for (i = relay->pit; i; i = i->next) {
            if (!ccnl_prefix_cmp(i->prefix, NULL, p, CMP_EXACT)
                && i->minsuffix == minsfx && i->maxsuffix == maxsfx
                && ((!ppkd && !i->ppkd) || buf_equal(ppkd, i->ppkd))) {
                break;
            }
        }

        if (!i) { // this is a new/unknown I request: create and propagate
            i = ccnl_interest_new(relay, from, &buf, &p, minsfx, maxsfx, &ppkd);

            if (i) { // CONFORM: Step 3 (and 4)
                DEBUGMSG(7, "  created new interest entry %p\n", (void *) i);

                if (scope > 2) {
                    ccnl_interest_propagate(relay, i);
                }
            }
        }
        else if (scope > 2 && (from->flags & CCNL_FACE_FLAGS_FWDALLI)) {
            DEBUGMSG(7, "  old interest, nevertheless propagated %p\n",
                     (void *) i);
            ccnl_interest_propagate(relay, i);
        }

        if (i) { // store the I request, for the incoming face (Step 3)
            DEBUGMSG(7, "  appending interest entry %p\n", (void *) i);
            ccnl_interest_append_pending(i, from);
        }
    }
    else {   // content
        DEBUGMSG(6, "  content=<%s>\n", ccnl_prefix_to_path(p));
        from->stat.received_content++;

        // CONFORM: Step 1:
        for (c = relay->contents; c; c = c->next) {
            if (buf_equal(c->pkt, buf)) {
                DEBUGMSG(1, "content is dup: skip\n");
                goto Skip;
            }
        }

        c = ccnl_content_new(relay, &buf, &p, &ppkd, content, contlen);

        if (c) { // CONFORM: Step 2 (and 3)
            if (!ccnl_content_serve_pending(relay, c, from)) { // unsolicited content
                // CONFORM: "A node MUST NOT forward unsolicited data [...]"
                DEBUGMSG(7, "  removed because no matching interest\n");
                free_content(c);
                goto Skip;
            }
#if CCNL_DYNAMIC_FIB
            else {
                /* content has matched an interest, we consider this name as available on this face */
                ccnl_content_learn_name_route(relay, c->name, from, relay->fib_threshold_prefix, 0);
            }
#endif

            if (relay->max_cache_entries != 0) { // it's set to -1 or a limit
                DEBUGMSG(7, "  adding content to cache\n");
                ccnl_content_add2cache(relay, c);
            }
            else {
                DEBUGMSG(7, "  content not added to cache\n");
                free_content(c);
            }
        }
    }

Skip:
    rc = 0;
Done:
    free_prefix(p);
    free_3ptr_list(buf, nonce, ppkd);
    DEBUGMSG(1, "leaving\n");
    return rc;
}