Tidy up the receive calls and eliminate the need for found_pkt

[ISC-Bugs #25066]

diff --git a/RELNOTES b/RELNOTES
index 8e3c09637dc5893d82fa828a07c69ce847a34e12..2ce2ea7f33aec153fcca04b249a8108a61f9d68d 100644 (file)
--- a/RELNOTES
+++ b/RELNOTES
@@ -71,6 +71,9 @@ work on other platforms. Please report any problems and suggested fixes to
   from the DNS client code.
   [ISC-Bugs 26287].
 
+- Tidy up the receive calls and eliminate the need for found_pkt
+  [ISC-Bugs #25066]
+ 
                        Changes since 4.2.2
 
 - Fix the code that checks for an existing DDNS transaction to cancel

diff --git a/common/socket.c b/common/socket.c
index a48404b0bdcde1bcda60c6be632ce9ec602d3ea6..fa7712818f815cfd257bd7f3f8f3d3ce662152f6 100644 (file)
--- a/common/socket.c
+++ b/common/socket.c
@@ -765,7 +765,7 @@ ssize_t receive_packet (interface, buf, len, from, hfrom)
        struct sockaddr_in *from;
        struct hardware *hfrom;
 {
-#if !defined(USE_V4_PKTINFO)
+#if !(defined(IP_PKTINFO) && defined(IP_RECVPKTINFO) && defined(USE_V4_PKTINFO))
        SOCKLEN_T flen = sizeof *from;
 #endif
        int result;
@@ -788,7 +788,6 @@ ssize_t receive_packet (interface, buf, len, from, hfrom)
        struct cmsghdr *cmsg;
        struct in_pktinfo *pktinfo;
        unsigned int ifindex;
-       int found_pktinfo;
 
        /*
         * If necessary allocate space for the control message header.
@@ -831,7 +830,7 @@ ssize_t receive_packet (interface, buf, len, from, hfrom)
         * We set up some space for a "control message". We have 
         * previously asked the kernel to give us packet 
         * information (when we initialized the interface), so we
-        * should get the destination address from that.
+        * should get the interface index from that.
         */
        m.msg_control = control_buf;
        m.msg_controllen = control_buf_len;
@@ -842,12 +841,8 @@ ssize_t receive_packet (interface, buf, len, from, hfrom)
                /*
                 * If we did read successfully, then we need to loop
                 * through the control messages we received and 
-                * find the one with our destination address.
-                *
-                * We also keep a flag to see if we found it. If we 
-                * didn't, then we consider this to be an error.
+                * find the one with our inteface index.
                 */
-               found_pktinfo = 0;
                cmsg = CMSG_FIRSTHDR(&m);
                while (cmsg != NULL) {
                        if ((cmsg->cmsg_level == IPPROTO_IP) && 
@@ -861,18 +856,21 @@ ssize_t receive_packet (interface, buf, len, from, hfrom)
                                 * the discover code.
                                 */
                                memcpy(hfrom->hbuf, &ifindex, sizeof(ifindex));
-                               found_pktinfo = 1;
+                               return (result);
                        }
                        cmsg = CMSG_NXTHDR(&m, cmsg);
                }
-               if (!found_pktinfo) {
-                       result = -1;
-                       errno = EIO;
-               }
+
+               /*
+                * We didn't find the necessary control message
+                * flag it as an error
+                */
+               result = -1;
+               errno = EIO;
        }
 #else
-               result = recvfrom (interface -> rfdesc, (char *)buf, len, 0,
-                                  (struct sockaddr *)from, &flen);
+               result = recvfrom(interface -> rfdesc, (char *)buf, len, 0,
+                                 (struct sockaddr *)from, &flen);
 #endif /* IP_PKTINFO ... */
 #ifdef IGNORE_HOSTUNREACH
        } while (result < 0 &&
@@ -880,7 +878,7 @@ ssize_t receive_packet (interface, buf, len, from, hfrom)
                  errno == ECONNREFUSED) &&
                 retry++ < 10);
 #endif
-       return result;
+       return (result);
 }
 
 #endif /* USE_SOCKET_RECEIVE */
@@ -897,7 +895,6 @@ receive_packet6(struct interface_info *interface,
        int result;
        struct cmsghdr *cmsg;
        struct in6_pktinfo *pktinfo;
-       int found_pktinfo;
 
        /*
         * If necessary allocate space for the control message header.
@@ -952,11 +949,7 @@ receive_packet6(struct interface_info *interface,
                 * If we did read successfully, then we need to loop
                 * through the control messages we received and 
                 * find the one with our destination address.
-                *
-                * We also keep a flag to see if we found it. If we 
-                * didn't, then we consider this to be an error.
                 */
-               found_pktinfo = 0;
                cmsg = CMSG_FIRSTHDR(&m);
                while (cmsg != NULL) {
                        if ((cmsg->cmsg_level == IPPROTO_IPV6) && 
@@ -964,17 +957,21 @@ receive_packet6(struct interface_info *interface,
                                pktinfo = (struct in6_pktinfo *)CMSG_DATA(cmsg);
                                *to_addr = pktinfo->ipi6_addr;
                                *if_idx = pktinfo->ipi6_ifindex;
-                               found_pktinfo = 1;
+
+                               return (result);
                        }
                        cmsg = CMSG_NXTHDR(&m, cmsg);
                }
-               if (!found_pktinfo) {
-                       result = -1;
-                       errno = EIO;
-               }
+
+               /*
+                * We didn't find the necessary control message
+                * flag is as an error
+                */
+               result = -1;
+               errno = EIO;
        }
 
-       return result;
+       return (result);
 }
 #endif /* DHCPv6 */