MINOR: quic: store the DCID as an offset

Using an offset instead of a pointer into the datagram buffer is less
error-prone as we do not have to manually fixup that pointer when the
datagram is moved somewhere else in memory.

diff --git a/include/haproxy/quic_sock-t.h b/include/haproxy/quic_sock-t.h
index eebafba52aee4fab79bcd472a1b1d47a9eabbd43..7358017572b09c073ba95fb4d0833153a3ab1de4 100644 (file)
--- a/include/haproxy/quic_sock-t.h
+++ b/include/haproxy/quic_sock-t.h
@@ -27,7 +27,7 @@ struct quic_dgram {
        void *owner;
        unsigned char *buf;
        size_t len;
-       unsigned char *dcid;
+       size_t dcid_off;
        size_t dcid_len;
        struct sockaddr_storage saddr;
        struct sockaddr_storage daddr;

diff --git a/src/quic_rx.c b/src/quic_rx.c
index 576ecdcc843ccf3f2be1d2b55a1c53c223a60c97..4f2cb14a9324b5a3053642210d5580becba2b59e 100644 (file)
--- a/src/quic_rx.c
+++ b/src/quic_rx.c
@@ -1977,7 +1977,7 @@ static int quic_rx_pkt_parse(struct quic_conn *qc, struct quic_rx_packet *pkt,
                 */
                if (!(pkt->flags & QUIC_FL_RX_PACKET_DGRAM_FIRST) &&
                    (pkt->dcid.len != dgram->dcid_len ||
-                    memcmp(dgram->dcid, pkt->dcid.data, pkt->dcid.len))) {
+                    memcmp(dgram->buf + dgram->dcid_off, pkt->dcid.data, pkt->dcid.len))) {
                        TRACE_PROTO("Packet dropped", QUIC_EV_CONN_LPKT);
                        goto drop;
                }
@@ -2184,7 +2184,7 @@ static int quic_rx_pkt_parse(struct quic_conn *qc, struct quic_rx_packet *pkt,
                 */
                if (!(pkt->flags & QUIC_FL_RX_PACKET_DGRAM_FIRST) &&
                    (pkt->dcid.len != dgram->dcid_len ||
-                    memcmp(dgram->dcid, pkt->dcid.data, pkt->dcid.len))) {
+                    memcmp(dgram->buf + dgram->dcid_off, pkt->dcid.data, pkt->dcid.len))) {
                        TRACE_PROTO("RX pkt dropped", QUIC_EV_CONN_LPKT);
                        goto drop;
                }

diff --git a/src/quic_sock.c b/src/quic_sock.c
index 72a07f1b7df6381539f918aaaf7a081c1c4bbbce..ea9a8e0e3031e10c98f60cc6927ed60bd02fa3f1 100644 (file)
--- a/src/quic_sock.c
+++ b/src/quic_sock.c
@@ -221,14 +221,16 @@ struct task *quic_lstnr_dghdlr(struct task *t, void *ctx, unsigned int state)
  * <end> being at one byte past the end of this datagram.
  * Returns 1 if succeeded, 0 if not.
  */
-static int quic_get_dgram_dcid(unsigned char *pos, const unsigned char *end,
-                               unsigned char **dcid, size_t *dcid_len)
+static int quic_get_dgram_dcid(unsigned char *start, const unsigned char *end,
+                               size_t *dcid_off, size_t *dcid_len)
 {
+       unsigned char *pos;
        int ret = 0, long_header;
        size_t minlen, skip;
 
        TRACE_ENTER(QUIC_EV_CONN_RXPKT);
 
+       pos = start;
        if (!(*pos & QUIC_PACKET_FIXED_BIT)) {
                TRACE_PROTO("fixed bit not set", QUIC_EV_CONN_RXPKT);
                goto err;
@@ -246,7 +248,7 @@ static int quic_get_dgram_dcid(unsigned char *pos, const unsigned char *end,
        if (*dcid_len > QUIC_CID_MAXLEN || end - pos <= *dcid_len)
                goto err;
 
-       *dcid = pos;
+       *dcid_off = pos - start;
 
        ret = 1;
  leave:
@@ -261,7 +263,7 @@ static int quic_get_dgram_dcid(unsigned char *pos, const unsigned char *end,
 /* Initialize a QUIC datagram. */
 static void quic_dgram_init(struct quic_dgram *dgram,
                             unsigned char *pos, size_t len, void *owner,
-                            unsigned char *dcid, size_t dcid_len,
+                            size_t dcid_off, size_t dcid_len,
                             struct sockaddr_storage *saddr,
                             struct sockaddr_storage *daddr)
 {
@@ -269,7 +271,7 @@ static void quic_dgram_init(struct quic_dgram *dgram,
        dgram->owner = owner;
        dgram->buf = pos;
        dgram->len = len;
-       dgram->dcid = dcid;
+       dgram->dcid_off = dcid_off;
        dgram->dcid_len = dcid_len;
        dgram->saddr = *saddr;
        dgram->daddr = *daddr;
@@ -393,7 +395,7 @@ static ssize_t quic_recv(int fd, void *out, size_t len,
 
 /* Low-level function to write a datagram to the buffer of the handler thread. */
 static int quic_dgram_write(unsigned char *pos, size_t len, void *owner,
-                            unsigned char *dcid, size_t dcid_len,
+                            size_t dcid_off, size_t dcid_len,
                             struct sockaddr_storage *saddr,
                             struct sockaddr_storage *daddr,
                             unsigned int cid_tid)
@@ -412,14 +414,12 @@ static int quic_dgram_write(unsigned char *pos, size_t len, void *owner,
                return 0;
 
        dgram = buf;
-       quic_dgram_init(dgram, pos, len, owner, dcid, dcid_len, saddr, daddr);
+       quic_dgram_init(dgram, pos, len, owner, dcid_off, dcid_len, saddr, daddr);
 
        data = (unsigned char *)(dgram + 1);
        memcpy(data, pos, len);
 
-       dgram->dcid = data + (dgram->dcid - dgram->buf);
        dgram->buf = data;
-
        mpring_write_commit(dst, buf, bring_len);
 
        /* typically quic_lstnr_dghdlr() */
@@ -430,9 +430,8 @@ static int quic_dgram_write(unsigned char *pos, size_t len, void *owner,
 
 int quic_dgram_requeue(struct quic_dgram *dgram, int cid_tid)
 {
-
        return quic_dgram_write(dgram->buf, dgram->len, dgram->owner,
-                               dgram->dcid, dgram->dcid_len,
+                               dgram->dcid_off, dgram->dcid_len,
                                &dgram->saddr, &dgram->daddr, cid_tid);
 }
 
@@ -444,7 +443,7 @@ int quic_dgram_requeue(struct quic_dgram *dgram, int cid_tid)
  * anymore after calling this function.
  */
 static int quic_lstnr_dgram_dispatch(unsigned char *pos, size_t len, struct listener *l,
-                                     unsigned char *dcid, size_t dcid_len,
+                                     size_t dcid_off, size_t dcid_len,
                                      struct sockaddr_storage *saddr,
                                      struct sockaddr_storage *daddr)
 {
@@ -455,10 +454,7 @@ static int quic_lstnr_dgram_dispatch(unsigned char *pos, size_t len, struct list
        if (!len)
                goto err;
 
-       if (!dcid && !quic_get_dgram_dcid(pos, pos + len, &dcid, &dcid_len))
-               goto err;
-
-       if ((cid_tid = quic_get_cid_tid(dcid, dcid_len, saddr, pos, len)) < 0) {
+       if ((cid_tid = quic_get_cid_tid(pos + dcid_off, dcid_len, saddr, pos, len)) < 0) {
                /* Use the current thread if CID not found. If a clients opens
                 * a connection with multiple packets, it is possible that
                 * several threads will deal with datagrams sharing the same
@@ -469,7 +465,7 @@ static int quic_lstnr_dgram_dispatch(unsigned char *pos, size_t len, struct list
                cid_tid = tid;
        }
 
-       if (!quic_dgram_write(pos, len, l, dcid, dcid_len, saddr, daddr, cid_tid))
+       if (!quic_dgram_write(pos, len, l, dcid_off, dcid_len, saddr, daddr, cid_tid))
                goto err;
 
        return 1;
@@ -492,7 +488,7 @@ void quic_lstnr_sock_fd_iocb(int fd)
        struct quic_transport_params *params;
        /* Source address */
        struct sockaddr_storage saddr = {0}, daddr = {0};
-       size_t max_sz;
+       size_t dcid_off, dcid_len, max_sz;
        int max_dgrams;
 
        BUG_ON(!l);
@@ -513,7 +509,8 @@ void quic_lstnr_sock_fd_iocb(int fd)
        if (ret <= 0)
                return;
 
-       quic_lstnr_dgram_dispatch(buf, ret, l, NULL, 0, &saddr, &daddr);
+       if (quic_get_dgram_dcid(buf, buf + ret, &dcid_off, &dcid_len))
+               quic_lstnr_dgram_dispatch(buf, ret, l, dcid_off, dcid_len, &saddr, &daddr);
 
        if (--max_dgrams > 0)
                goto start;
@@ -821,8 +818,8 @@ int qc_rcv_buf(struct quic_conn *qc)
        struct sockaddr_storage saddr = {0}, daddr = {0};
        struct quic_dgram dgram, *new_dgram;
        struct buffer buf = BUF_NULL;
-       unsigned char *dgram_buf, *dcid;
-       size_t dcid_len;
+       unsigned char *dgram_buf;
+       size_t dcid_off, dcid_len;
        ssize_t ret = 0;
        struct listener *l = qc->li;
 
@@ -856,10 +853,10 @@ int qc_rcv_buf(struct quic_conn *qc)
 
                TRACE_DEVEL("read datagram", QUIC_EV_CONN_RCV, qc, new_dgram);
 
-               if (!quic_get_dgram_dcid(dgram_buf, dgram_buf + ret, &dcid, &dcid_len))
+               if (!quic_get_dgram_dcid(dgram_buf, dgram_buf + ret, &dcid_off, &dcid_len))
                        continue;
 
-               if (l && !qc_check_dcid(qc, dcid, dcid_len)) {
+               if (l && !qc_check_dcid(qc, dgram_buf + dcid_off, dcid_len)) {
                        /* Datagram received by error on the connection FD, dispatch it
                         * to its associated quic-conn.
                         *
@@ -867,11 +864,11 @@ int qc_rcv_buf(struct quic_conn *qc)
                         */
                        TRACE_STATE("datagram for other connection on quic-conn socket, requeue it", QUIC_EV_CONN_RCV, qc);
 
-                       quic_lstnr_dgram_dispatch(dgram_buf, ret, l, dcid, dcid_len, &saddr, &daddr);
+                       quic_lstnr_dgram_dispatch(dgram_buf, ret, l, dcid_off, dcid_len, &saddr, &daddr);
                        continue;
                }
 
-               quic_dgram_init(new_dgram, dgram_buf, ret, NULL, dcid, dcid_len, &saddr, &daddr);
+               quic_dgram_init(new_dgram, dgram_buf, ret, NULL, dcid_off, dcid_len, &saddr, &daddr);
                quic_dgram_parse(new_dgram, qc, l ? &l->obj_type :
                                 (qc->conn ? &__objt_server(qc->conn->target)->obj_type : NULL));
        } while (ret > 0);

diff --git a/src/quic_trace.c b/src/quic_trace.c
index 6911893f551ffe01f199235d0bb796ad90531e79..2dd12b805e4032766bcb7d41fd8282d0a42498d7 100644 (file)
--- a/src/quic_trace.c
+++ b/src/quic_trace.c
@@ -629,7 +629,7 @@ static void quic_trace(enum trace_level level, uint64_t mask, const struct trace
                        }
                        /* DCID */
                        for (i = 0; i < dgram->dcid_len; ++i)
-                               chunk_appendf(&trace_buf, "%02x", dgram->dcid[i]);
+                               chunk_appendf(&trace_buf, "%02x", dgram->buf[dgram->dcid_off + i]);
 
                }
        }