isisd: keep original TLVs when purging in response to confusion

Signed-off-by: Christian Franke <chris@opensourcerouting.org>

diff --git a/isisd/isis_lsp.c b/isisd/isis_lsp.c
index 6bf6e45d9239b6253236ab8f4a3760701bca9dab..e324a303d8ba673d81427cfdead8f6177b501877 100644 (file)
--- a/isisd/isis_lsp.c
+++ b/isisd/isis_lsp.c
@@ -290,12 +290,21 @@ int lsp_compare(char *areatag, struct isis_lsp *lsp, uint32_t seqno,
        return LSP_OLDER;
 }
 
-static void put_lsp_hdr(struct isis_lsp *lsp, size_t *len_pointer)
+static void put_lsp_hdr(struct isis_lsp *lsp, size_t *len_pointer, bool keep)
 {
        uint8_t pdu_type =
                (lsp->level == IS_LEVEL_1) ? L1_LINK_STATE : L2_LINK_STATE;
        struct isis_lsp_hdr *hdr = &lsp->hdr;
        struct stream *stream = lsp->pdu;
+       size_t orig_getp, orig_endp;
+
+       if (keep) {
+               orig_getp = stream_get_getp(lsp->pdu);
+               orig_endp = stream_get_endp(lsp->pdu);
+       }
+
+       stream_set_getp(lsp->pdu, 0);
+       stream_set_endp(lsp->pdu, 0);
 
        fill_fixed_hdr(pdu_type, stream);
 
@@ -307,6 +316,11 @@ static void put_lsp_hdr(struct isis_lsp *lsp, size_t *len_pointer)
        stream_putl(stream, hdr->seqno);
        stream_putw(stream, hdr->checksum);
        stream_putc(stream, hdr->lsp_bits);
+
+       if (keep) {
+               stream_set_endp(lsp->pdu, orig_endp);
+               stream_set_getp(lsp->pdu, orig_getp);
+       }
 }
 
 static void lsp_add_auth(struct isis_lsp *lsp)
@@ -325,8 +339,7 @@ static void lsp_pack_pdu(struct isis_lsp *lsp)
        lsp_add_auth(lsp);
 
        size_t len_pointer;
-       stream_reset(lsp->pdu);
-       put_lsp_hdr(lsp, &len_pointer);
+       put_lsp_hdr(lsp, &len_pointer, false);
        isis_pack_tlvs(lsp->tlvs, lsp->pdu, len_pointer, false, true);
 
        lsp->hdr.pdu_len = stream_get_endp(lsp->pdu);
@@ -457,16 +470,10 @@ void lsp_update(struct isis_lsp *lsp, struct isis_lsp_hdr *hdr,
                lsp->own_lsp = 0;
        }
 
+       lsp_update_data(lsp, hdr, tlvs, stream, area, level);
        if (confusion) {
-               lsp_clear_data(lsp);
-               if (lsp->pdu != NULL)
-                       stream_free(lsp->pdu);
-               lsp->pdu = stream_new(LLC_LEN + area->lsp_mtu);
-               lsp->age_out = ZERO_AGE_LIFETIME;
-               lsp->hdr.rem_lifetime = 0;
-               lsp_pack_pdu(lsp);
-       } else {
-               lsp_update_data(lsp, hdr, tlvs, stream, area, level);
+               lsp->hdr.rem_lifetime = hdr->rem_lifetime = 0;
+               put_lsp_hdr(lsp, NULL, true);
        }
 
        /* insert the lsp back into the database */
@@ -523,7 +530,7 @@ struct isis_lsp *lsp_new(struct isis_area *area, u_char *lsp_id,
        lsp->level = level;
        lsp->age_out = ZERO_AGE_LIFETIME;
        lsp_link_fragment(lsp, lsp0);
-       put_lsp_hdr(lsp, NULL);
+       put_lsp_hdr(lsp, NULL, false);
 
        if (isis->debugs & DEBUG_EVENTS)
                zlog_debug("New LSP with ID %s-%02x-%02x len %d seqnum %08x",