UDP: extended datagram context.

Sometimes it is required to process datagram properties at higher level (i.e.
QUIC is interested in source address which may change and IP options).  The
patch adds ngx_udp_dgram_t structure used to pass packet-related information
in c->udp.

3 files changed, 34 insertions, 30 deletions

diff --git a/src/event/ngx_event.h b/src/event/ngx_event.h
index 17e9d58d0..e023af027 100644
--- a/src/event/ngx_event.h
+++ b/src/event/ngx_event.h
@@ -169,11 +169,18 @@ struct ngx_event_aio_s {
 
 #if !(NGX_WIN32)
 
+typedef struct {
+    ngx_buf_t                 *buffer;
+    struct sockaddr           *sockaddr;
+    socklen_t                  socklen;
+} ngx_udp_dgram_t;
+
+
 struct ngx_udp_connection_s {
     ngx_rbtree_node_t          node;
     ngx_connection_t          *connection;
     ngx_str_t                  key;
-    ngx_buf_t                 *buffer;
+    ngx_udp_dgram_t           *dgram;
 };
 
 #endif
diff --git a/src/event/ngx_event_udp.c b/src/event/ngx_event_udp.c
index d6b11d0b6..ca70e3bd6 100644
--- a/src/event/ngx_event_udp.c
+++ b/src/event/ngx_event_udp.c
@@ -29,12 +29,13 @@ ngx_event_recvmsg(ngx_event_t *ev)
     ngx_buf_t          buf;
     ngx_log_t         *log;
     ngx_err_t          err;
-    socklen_t          socklen, local_socklen;
+    socklen_t          local_socklen;
     ngx_event_t       *rev, *wev;
     struct iovec       iov[1];
     struct msghdr      msg;
     ngx_sockaddr_t     sa, lsa;
-    struct sockaddr   *sockaddr, *local_sockaddr;
+    ngx_udp_dgram_t    dgram;
+    struct sockaddr   *local_sockaddr;
     ngx_listening_t   *ls;
     ngx_event_conf_t  *ecf;
     ngx_connection_t  *c, *lc;
@@ -131,21 +132,21 @@ ngx_event_recvmsg(ngx_event_t *ev)
         }
 #endif
 
-        sockaddr = msg.msg_name;
-        socklen = msg.msg_namelen;
+        dgram.sockaddr = msg.msg_name;
+        dgram.socklen = msg.msg_namelen;
 
-        if (socklen > (socklen_t) sizeof(ngx_sockaddr_t)) {
-            socklen = sizeof(ngx_sockaddr_t);
+        if (dgram.socklen > (socklen_t) sizeof(ngx_sockaddr_t)) {
+            dgram.socklen = sizeof(ngx_sockaddr_t);
         }
 
-        if (socklen == 0) {
+        if (dgram.socklen == 0) {
 
             /*
              * on Linux recvmsg() returns zero msg_namelen
              * when receiving packets from unbound AF_UNIX sockets
              */
 
-            socklen = sizeof(struct sockaddr);
+            dgram.socklen = sizeof(struct sockaddr);
             ngx_memzero(&sa, sizeof(struct sockaddr));
             sa.sockaddr.sa_family = ls->sockaddr->sa_family;
         }
@@ -223,15 +224,16 @@ ngx_event_recvmsg(ngx_event_t *ev)
 
 #endif
 
-        key.data = (u_char *) sockaddr;
-        key.len = socklen;
+        key.data = (u_char *) dgram.sockaddr;
+        key.len = dgram.socklen;
 
 #if (NGX_HAVE_UNIX_DOMAIN)
 
-        if (sockaddr->sa_family == AF_UNIX) {
-            struct sockaddr_un *saun = (struct sockaddr_un *) sockaddr;
+        if (dgram.sockaddr->sa_family == AF_UNIX) {
+            struct sockaddr_un *saun = (struct sockaddr_un *) dgram.sockaddr;
 
-            if (socklen <= (socklen_t) offsetof(struct sockaddr_un, sun_path)
+            if (dgram.socklen <= (socklen_t) offsetof(struct sockaddr_un,
+                                                      sun_path)
                 || saun->sun_path[0] == '\0')
             {
                 ngx_log_debug0(NGX_LOG_DEBUG_EVENT, ngx_cycle->log, 0,
@@ -268,13 +270,6 @@ ngx_event_recvmsg(ngx_event_t *ev)
             }
 #endif
 
-#if (NGX_QUIC)
-            if (ls->quic) {
-                c->socklen = socklen;
-                ngx_memcpy(c->sockaddr, sockaddr, socklen);
-            }
-#endif
-
             ngx_memzero(&buf, sizeof(ngx_buf_t));
 
             buf.pos = buffer;
@@ -284,7 +279,9 @@ ngx_event_recvmsg(ngx_event_t *ev)
 
             rev = c->read;
 
-            c->udp->buffer = &buf;
+            dgram.buffer = &buf;
+
+            c->udp->dgram = &dgram;
 
             rev->ready = 1;
             rev->active = 0;
@@ -292,7 +289,7 @@ ngx_event_recvmsg(ngx_event_t *ev)
             rev->handler(rev);
 
             if (c->udp) {
-                c->udp->buffer = NULL;
+                c->udp->dgram = NULL;
             }
 
             rev->ready = 0;
@@ -315,7 +312,7 @@ ngx_event_recvmsg(ngx_event_t *ev)
 
         c->shared = 1;
         c->type = SOCK_DGRAM;
-        c->socklen = socklen;
+        c->socklen = dgram.socklen;
 
 #if (NGX_STAT_STUB)
         (void) ngx_atomic_fetch_add(ngx_stat_active, 1);
@@ -327,7 +324,7 @@ ngx_event_recvmsg(ngx_event_t *ev)
             return;
         }
 
-        len = socklen;
+        len = dgram.socklen;
 
 #if (NGX_QUIC)
         if (ls->quic) {
@@ -341,7 +338,7 @@ ngx_event_recvmsg(ngx_event_t *ev)
             return;
         }
 
-        ngx_memcpy(c->sockaddr, sockaddr, socklen);
+        ngx_memcpy(c->sockaddr, dgram.sockaddr, dgram.socklen);
 
         log = ngx_palloc(c->pool, sizeof(ngx_log_t));
         if (log == NULL) {
@@ -483,17 +480,17 @@ ngx_udp_shared_recv(ngx_connection_t *c, u_char *buf, size_t size)
     ssize_t     n;
     ngx_buf_t  *b;
 
-    if (c->udp == NULL || c->udp->buffer == NULL) {
+    if (c->udp == NULL || c->udp->dgram == NULL) {
         return NGX_AGAIN;
     }
 
-    b = c->udp->buffer;
+    b = c->udp->dgram->buffer;
 
     n = ngx_min(b->last - b->pos, (ssize_t) size);
 
     ngx_memcpy(buf, b->pos, n);
 
-    c->udp->buffer = NULL;
+    c->udp->dgram = NULL;
 
     c->read->ready = 0;
     c->read->active = 1;
diff --git a/src/event/quic/ngx_event_quic.c b/src/event/quic/ngx_event_quic.c
index 22317db25..77f0eeda8 100644
--- a/src/event/quic/ngx_event_quic.c
+++ b/src/event/quic/ngx_event_quic.c
@@ -1920,7 +1920,7 @@ ngx_quic_input_handler(ngx_event_t *rev)
         }
     }
 
-    b = c->udp->buffer;
+    b = c->udp->dgram->buffer;
 
     qc->received += (b->last - b->pos);