In the big ibuf API refactor I also broke the optparamlen handling
by using one variable for two things.
All the size handling in session_open() can be simplified since
ibuf_size() is cheap to call.
I think the result is cleaner than the code before. It is still somewhat
funky because there are a fair amount of conditions to cover now.
--
:wq Claudio
Index: session.c
===================================================================
RCS file: /cvs/src/usr.sbin/bgpd/session.c,v
retrieving revision 1.452
diff -u -p -r1.452 session.c
--- session.c 27 Oct 2023 09:40:27 -0000 1.452
+++ session.c 27 Oct 2023 11:00:13 -0000
@@ -1471,8 +1471,9 @@ session_open(struct peer *p)
{
struct bgp_msg *buf;
struct ibuf *opb;
- uint16_t len, optparamlen = 0, holdtime;
- uint8_t i, op_type;
+ size_t optparamlen;
+ uint16_t holdtime;
+ uint8_t i;
int errs = 0, extlen = 0;
int mpcapa = 0;
@@ -1556,16 +1557,16 @@ session_open(struct peer *p)
if (optparamlen == 0) {
/* nothing */
} else if (optparamlen + 2 >= 255) {
- /* RFC9072: 2 byte length instead of 1 + 3 byte extra header */
- optparamlen += sizeof(op_type) + 2 + 3;
+ /* RFC9072: use 255 as magic size and request extra header */
optparamlen = 255;
extlen = 1;
} else {
- optparamlen += sizeof(op_type) + 1;
+ /* regular capabilities header */
+ optparamlen += 2;
}
- len = MSGSIZE_OPEN_MIN + optparamlen;
- if (errs || (buf = session_newmsg(OPEN, len)) == NULL) {
+ if (errs || (buf = session_newmsg(OPEN,
+ MSGSIZE_OPEN_MIN + optparamlen)) == NULL) {
ibuf_free(opb);
bgp_fsm(p, EVNT_CON_FATAL);
return;
@@ -1584,20 +1585,19 @@ session_open(struct peer *p)
errs += ibuf_add_n8(buf->buf, optparamlen);
if (extlen) {
- /* write RFC9072 extra header */
+ /* RFC9072 extra header which spans over the capabilities hdr */
errs += ibuf_add_n8(buf->buf, OPT_PARAM_EXT_LEN);
- errs += ibuf_add_n16(buf->buf, optparamlen - 3);
+ errs += ibuf_add_n16(buf->buf, ibuf_size(opb) + 1 + 2);
}
if (optparamlen) {
errs += ibuf_add_n8(buf->buf, OPT_PARAM_CAPABILITIES);
- optparamlen = ibuf_size(opb);
if (extlen) {
/* RFC9072: 2-byte extended length */
- errs += ibuf_add_n16(buf->buf, optparamlen);
+ errs += ibuf_add_n16(buf->buf, ibuf_size(opb));
} else {
- errs += ibuf_add_n8(buf->buf, optparamlen);
+ errs += ibuf_add_n8(buf->buf, ibuf_size(opb));
}
errs += ibuf_add_buf(buf->buf, opb);
}
