Initialize off_outermostlinkhdr and off_prevlinkhdr at start.

Currently off_outermostlinkhdr is always set to zero rather than
the true offsets. It is currently only used in one place where
the correct offset is zero but this is not semantically correct.
It is instead better to initialize the offsets to the initial
values computed for the link type.

diff --git a/gencode.c b/gencode.c
index 4a00f955c1b17f7c40387b3135db6df69a14fc1f..45eb42d54dda94a651ea3ca7724cf99304aa21f1 100644 (file)
--- a/gencode.c
+++ b/gencode.c
@@ -981,21 +981,21 @@ init_linktype(p)
                off_linkpl.constant_part = 6;
                off_nl = 0;             /* XXX in reality, variable! */
                off_nl_nosnap = 0;      /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_ARCNET_LINUX:
                off_linktype = 4;
                off_linkpl.constant_part = 8;
                off_nl = 0;             /* XXX in reality, variable! */
                off_nl_nosnap = 0;      /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_EN10MB:
                off_linktype = 12;
                off_linkpl.constant_part = 14;  /* Ethernet header length */
                off_nl = 0;             /* Ethernet II */
                off_nl_nosnap = 3;      /* 802.3+802.2 */
-               return;
+               break;
 
        case DLT_SLIP:
                /*
@@ -1006,7 +1006,7 @@ init_linktype(p)
                off_linkpl.constant_part = 16;
                off_nl = 0;
                off_nl_nosnap = 0;      /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_SLIP_BSDOS:
                /* XXX this may be the same as the DLT_PPP_BSDOS case */
@@ -1015,7 +1015,7 @@ init_linktype(p)
                off_linkpl.constant_part = 24;
                off_nl = 0;
                off_nl_nosnap = 0;      /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_NULL:
        case DLT_LOOP:
@@ -1023,14 +1023,14 @@ init_linktype(p)
                off_linkpl.constant_part = 4;
                off_nl = 0;
                off_nl_nosnap = 0;      /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_ENC:
                off_linktype = 0;
                off_linkpl.constant_part = 12;
                off_nl = 0;
                off_nl_nosnap = 0;      /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_PPP:
        case DLT_PPP_PPPD:
@@ -1040,7 +1040,7 @@ init_linktype(p)
                off_linkpl.constant_part = 4;   /* skip HDLC-like framing and protocol field */
                off_nl = 0;
                off_nl_nosnap = 0;      /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_PPP_ETHER:
                /*
@@ -1051,14 +1051,14 @@ init_linktype(p)
                off_linkpl.constant_part = 8;
                off_nl = 0;
                off_nl_nosnap = 0;      /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_PPP_BSDOS:
                off_linktype = 5;
                off_linkpl.constant_part = 24;
                off_nl = 0;
                off_nl_nosnap = 0;      /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_FDDI:
                /*
@@ -1075,7 +1075,7 @@ init_linktype(p)
                off_linkpl.constant_part += pcap_fddipad;
                off_nl = 8;             /* 802.2+SNAP */
                off_nl_nosnap = 3;      /* 802.2 */
-               return;
+               break;
 
        case DLT_IEEE802:
                /*
@@ -1105,7 +1105,7 @@ init_linktype(p)
                off_linkpl.constant_part = 14;  /* Token Ring MAC header length */
                off_nl = 8;             /* 802.2+SNAP */
                off_nl_nosnap = 3;      /* 802.2 */
-               return;
+               break;
 
        case DLT_IEEE802_11:
        case DLT_PRISM_HEADER:
@@ -1133,7 +1133,7 @@ init_linktype(p)
                off_linkpl.is_variable = 1;
                off_nl = 8;             /* 802.2+SNAP */
                off_nl_nosnap = 3;      /* 802.2 */
-               return;
+               break;
 
        case DLT_PPI:
                /*
@@ -1150,7 +1150,7 @@ init_linktype(p)
                off_linkpl.is_variable = 1;
                off_nl = 8;             /* 802.2+SNAP */
                off_nl_nosnap = 3;      /* 802.2 */
-               return;
+               break;
 
        case DLT_ATM_RFC1483:
        case DLT_ATM_CLIP:      /* Linux ATM defines this */
@@ -1169,7 +1169,7 @@ init_linktype(p)
                off_linkpl.constant_part = 0;   /* packet begins with LLC header */
                off_nl = 8;             /* 802.2+SNAP */
                off_nl_nosnap = 3;      /* 802.2 */
-               return;
+               break;
 
        case DLT_SUNATM:
                /*
@@ -1185,7 +1185,7 @@ init_linktype(p)
                off_linkpl.constant_part = off_payload; /* if LLC-encapsulated */
                off_nl = 8;             /* 802.2+SNAP */
                off_nl_nosnap = 3;      /* 802.2 */
-               return;
+               break;
 
        case DLT_RAW:
        case DLT_IPV4:
@@ -1194,14 +1194,14 @@ init_linktype(p)
                off_linkpl.constant_part = 0;
                off_nl = 0;
                off_nl_nosnap = 0;      /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_LINUX_SLL:     /* fake header for Linux cooked socket */
                off_linktype = 14;
                off_linkpl.constant_part = 16;
                off_nl = 0;
                off_nl_nosnap = 0;      /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_LTALK:
                /*
@@ -1213,7 +1213,7 @@ init_linktype(p)
                off_linkpl.constant_part = 0;
                off_nl = 0;
                off_nl_nosnap = 0;      /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_IP_OVER_FC:
                /*
@@ -1230,7 +1230,7 @@ init_linktype(p)
                off_linkpl.constant_part = 16;
                off_nl = 8;             /* 802.2+SNAP */
                off_nl_nosnap = 3;      /* 802.2 */
-               return;
+               break;
 
        case DLT_FRELAY:
                /*
@@ -1241,7 +1241,7 @@ init_linktype(p)
                off_linkpl.constant_part = 0;
                off_nl = 0;
                off_nl_nosnap = 0;      /* no 802.2 LLC */
-               return;
+               break;
 
                 /*
                  * the only BPF-interesting FRF.16 frames are non-control frames;
@@ -1253,21 +1253,21 @@ init_linktype(p)
                off_linkpl.constant_part = 0;
                off_nl = 4;
                off_nl_nosnap = 0;      /* XXX - for now -> no 802.2 LLC */
-               return;
+               break;
 
        case DLT_APPLE_IP_OVER_IEEE1394:
                off_linktype = 16;
                off_linkpl.constant_part = 18;
                off_nl = 0;
                off_nl_nosnap = 0;      /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_SYMANTEC_FIREWALL:
                off_linktype = 6;
                off_linkpl.constant_part = 44;
                off_nl = 0;             /* Ethernet II */
                off_nl_nosnap = 0;      /* XXX - what does it do with 802.3 packets? */
-               return;
+               break;
 
 #ifdef HAVE_NET_PFVAR_H
        case DLT_PFLOG:
@@ -1275,7 +1275,7 @@ init_linktype(p)
                off_linkpl.constant_part = PFLOG_HDRLEN;
                off_nl = 0;
                off_nl_nosnap = 0;      /* no 802.2 LLC */
-               return;
+               break;
 #endif
 
         case DLT_JUNIPER_MFR:
@@ -1288,21 +1288,21 @@ init_linktype(p)
                off_linkpl.constant_part = 4;
                off_nl = 0;
                off_nl_nosnap = -1;     /* no 802.2 LLC */
-                return;
+                break;
 
        case DLT_JUNIPER_ATM1:
                off_linktype = 4;               /* in reality variable between 4-8 */
                off_linkpl.constant_part = 4;   /* in reality variable between 4-8 */
                off_nl = 0;
                off_nl_nosnap = 10;
-               return;
+               break;
 
        case DLT_JUNIPER_ATM2:
                off_linktype = 8;               /* in reality variable between 8-12 */
                off_linkpl.constant_part = 8;   /* in reality variable between 8-12 */
                off_nl = 0;
                off_nl_nosnap = 10;
-               return;
+               break;
 
                /* frames captured on a Juniper PPPoE service PIC
                 * contain raw ethernet frames */
@@ -1312,70 +1312,70 @@ init_linktype(p)
                off_linktype = 16;
                off_nl = 18;            /* Ethernet II */
                off_nl_nosnap = 21;     /* 802.3+802.2 */
-               return;
+               break;
 
        case DLT_JUNIPER_PPPOE_ATM:
                off_linktype = 4;
                off_linkpl.constant_part = 6;
                off_nl = 0;
                off_nl_nosnap = -1;     /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_JUNIPER_GGSN:
                off_linktype = 6;
                off_linkpl.constant_part = 12;
                off_nl = 0;
                off_nl_nosnap = -1;     /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_JUNIPER_ES:
                off_linktype = 6;
                off_linkpl.constant_part = -1;  /* not really a network layer but raw IP addresses */
                off_nl = -1;            /* not really a network layer but raw IP addresses */
                off_nl_nosnap = -1;     /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_JUNIPER_MONITOR:
                off_linktype = 12;
                off_linkpl.constant_part = 12;
                off_nl = 0;             /* raw IP/IP6 header */
                off_nl_nosnap = -1;     /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_BACNET_MS_TP:
                off_linktype = -1;
                off_linkpl.constant_part = -1;
                off_nl = -1;
                off_nl_nosnap = -1;
-               return;
+               break;
 
        case DLT_JUNIPER_SERVICES:
                off_linktype = 12;
                off_linkpl.constant_part = -1;  /* L3 proto location dep. on cookie type */
                off_nl = -1;            /* L3 proto location dep. on cookie type */
                off_nl_nosnap = -1;     /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_JUNIPER_VP:
                off_linktype = 18;
                off_linkpl.constant_part = -1;
                off_nl = -1;
                off_nl_nosnap = -1;
-               return;
+               break;
 
        case DLT_JUNIPER_ST:
                off_linktype = 18;
                off_linkpl.constant_part = -1;
                off_nl = -1;
                off_nl_nosnap = -1;
-               return;
+               break;
 
        case DLT_JUNIPER_ISM:
                off_linktype = 8;
                off_linkpl.constant_part = -1;
                off_nl = -1;
                off_nl_nosnap = -1;
-               return;
+               break;
 
        case DLT_JUNIPER_VS:
        case DLT_JUNIPER_SRX_E2E:
@@ -1385,7 +1385,7 @@ init_linktype(p)
                off_linkpl.constant_part = -1;
                off_nl = -1;
                off_nl_nosnap = -1;
-               return;
+               break;
 
        case DLT_MTP2:
                off_li = 2;
@@ -1398,7 +1398,7 @@ init_linktype(p)
                off_linkpl.constant_part = -1;
                off_nl = -1;
                off_nl_nosnap = -1;
-               return;
+               break;
 
        case DLT_MTP2_WITH_PHDR:
                off_li = 6;
@@ -1411,7 +1411,7 @@ init_linktype(p)
                off_linkpl.constant_part = -1;
                off_nl = -1;
                off_nl_nosnap = -1;
-               return;
+               break;
 
        case DLT_ERF:
                off_li = 22;
@@ -1424,14 +1424,14 @@ init_linktype(p)
                off_linkpl.constant_part = -1;
                off_nl = -1;
                off_nl_nosnap = -1;
-               return;
+               break;
 
        case DLT_PFSYNC:
                off_linktype = -1;
                off_linkpl.constant_part = 4;
                off_nl = 0;
                off_nl_nosnap = 0;
-               return;
+               break;
 
        case DLT_AX25_KISS:
                /*
@@ -1441,14 +1441,14 @@ init_linktype(p)
                off_linkpl.constant_part = -1;
                off_nl = -1;            /* variable, min 16, max 71 steps of 7 */
                off_nl_nosnap = -1;     /* no 802.2 LLC */
-               return;
+               break;
 
        case DLT_IPNET:
                off_linktype = 1;
                off_linkpl.constant_part = 24;  /* ipnet header length */
                off_nl = 0;
                off_nl_nosnap = -1;
-               return;
+               break;
 
        case DLT_NETANALYZER:
                off_linkhdr.constant_part = 4;  /* Ethernet header is past 4-byte pseudo-header */
@@ -1456,7 +1456,7 @@ init_linktype(p)
                off_linkpl.constant_part = off_linkhdr.constant_part + 14;      /* pseudo-header+Ethernet header length */
                off_nl = 0;             /* Ethernet II */
                off_nl_nosnap = 3;      /* 802.3+802.2 */
-               return;
+               break;
 
        case DLT_NETANALYZER_TRANSPARENT:
                off_linkhdr.constant_part = 12; /* MAC header is past 4-byte pseudo-header, preamble, and SFD */
@@ -1464,7 +1464,7 @@ init_linktype(p)
                off_linkpl.constant_part = off_linkhdr.constant_part + 14;      /* pseudo-header+preamble+SFD+Ethernet header length */
                off_nl = 0;             /* Ethernet II */
                off_nl_nosnap = 3;      /* 802.3+802.2 */
-               return;
+               break;
 
        default:
                /*
@@ -1477,12 +1477,13 @@ init_linktype(p)
                        off_linkpl.constant_part = -1;
                        off_nl = -1;
                        off_nl_nosnap = -1;
-                       return;
+               } else {
+                       bpf_error("unknown data link type %d", linktype);
                }
-
+               break;
        }
-       bpf_error("unknown data link type %d", linktype);
-       /* NOTREACHED */
+
+       off_outermostlinkhdr = off_prevlinkhdr = off_linkhdr;
 }
 
 /*