X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/5cea2703185c6af1616dc338c43c6cf67b0bec60..fe225c551810e941ca1fc0d3fecee29cea7f16b9:/netdissect.h

diff --git a/netdissect.h b/netdissect.h
index 70c821d9..360c1eb9 100644
--- a/netdissect.h
+++ b/netdissect.h
@@ -56,36 +56,45 @@ typedef unsigned char nd_uint64_t[8];
 
 typedef signed char nd_int8_t[1];
 
+/*
+ * "unsigned char" so that sign extension isn't done on the
+ * individual bytes while they're being assembled.
+ */
+typedef unsigned char nd_int32_t[4];
+typedef unsigned char nd_int64_t[8];
+
 /*
  * Use this for IPv4 addresses and netmasks.
  *
  * It's defined as an array of octets, so that it's not guaranteed to
  * be aligned on its "natural" boundary (in some packet formats, it
- * *isn't* so aligned), and it's defined as a structure in the hopes
- * that this makes it harder to naively use EXTRACT_BE_U_4() to extract
- * the value - in many cases you just want to use UNALIGNED_MEMCPY() to
- * copy its value, so that it remains in network byte order.
+ * *isn't* so aligned).  We have separate EXTRACT_ calls for them;
+ * sometimes you want the host-byte-order value, other times you want
+ * the network-byte-order value.
+ *
+ * Don't use EXTRACT_BE_U_4() on them, use EXTRACT_IPV4_TO_HOST_ORDER()
+ * if you want them in host byte order and EXTRACT_IPV4_TO_NETWORK_ORDER()
+ * if you want them in network byte order (which you want with system APIs
+ * that expect network-order IPv4 addresses, such as inet_ntop()).
+ *
+ * If, on your little-endian machine (e.g., an "IBM-compatible PC", no matter
+ * what the OS, or an Intel Mac, no matter what the OS), you get the wrong
+ * answer, and you've used EXTRACT_BE_U_4(), do *N*O*T* "fix" this by using
+ * EXTRACT_LE_U_4(), fix it by using EXTRACT_IPV4_TO_NETWORK_ORDER(),
+ * otherwise you're breaking the result on big-endian machines (e.g.,
+ * most PowerPC/Power ISA machines, System/390 and z/Architecture, SPARC,
+ * etc.).
  *
- * (Among other things, we don't want somebody thinking "IPv4 addresses,
- * they're in network byte order, so we want EXTRACT_BE_U_4(), right?"
- * and then handing the result to system APIs that expect network-order
- * IPv4 addresses, such as inet_ntop(), on their little-endian PCs, getting
- * the wrong behavior, and concluding "oh, it must be in *little*-endian
- * order" and "fixing" it to use EXTRACT_LE_U_4().  Yes, people do this;
- * that's why Wireshark has tvb_get_ipv4(), to extract an IPv4 address from
- * a packet data buffer; it was introduced in reaction to somebody who
- * *had* done that.)
+ * Yes, people do this; that's why Wireshark has tvb_get_ipv4(), to extract
+ * an IPv4 address from a packet data buffer; it was introduced in reaction
+ * to somebody who *had* done that.
  */
-typedef struct {
-	unsigned char bytes[4];
-} nd_ipv4;
+typedef unsigned char nd_ipv4[4];
 
 /*
  * Use this for IPv6 addresses and netmasks.
  */
-typedef struct {
-	unsigned char bytes[16];
-} nd_ipv6;
+typedef unsigned char nd_ipv6[16];
 
 /*
  * Use this for MAC addresses.
@@ -283,16 +292,6 @@ struct netdissect_options {
  */
 #define MAXIMUM_SNAPLEN	262144
 
-#define ESRC(ep) ((ep)->ether_shost)
-#define EDST(ep) ((ep)->ether_dhost)
-
-#ifndef NTOHL
-#define NTOHL(x)	(x) = ntohl(x)
-#define NTOHS(x)	(x) = ntohs(x)
-#define HTONL(x)	(x) = htonl(x)
-#define HTONS(x)	(x) = htons(x)
-#endif
-
 /*
  * True if "l" bytes of "var" were captured.
  *
@@ -333,15 +332,22 @@ struct netdissect_options {
 /* True if "var" was captured */
 #define ND_TTEST(var) ND_TTEST2(var, sizeof(var))
 
+/* True if "*(p)" was captured */
+#define ND_TTEST_SIZE(p) ND_TTEST_LEN(p, sizeof(*(p)))
+
 /* Bail if "l" bytes of "var" were not captured */
 #define ND_TCHECK2(var, l) if (!ND_TTEST2(var, l)) goto trunc
 
+/* Bail out if "l" bytes from "p" were not captured */
 #define ND_TCHECK_LEN(p, l) if (!ND_TTEST_LEN(p, l)) goto trunc
 
 /* Bail if "var" was not captured */
 #define ND_TCHECK(var) ND_TCHECK2(var, sizeof(var))
 
-#define ND_PRINT(STUFF) (ndo->ndo_printf)STUFF
+/* Bail out if "*(p)" was not captured */
+#define ND_TCHECK_SIZE(p) ND_TCHECK_LEN(p, sizeof(*(p)))
+
+#define ND_PRINT(...) (ndo->ndo_printf)(ndo, __VA_ARGS__)
 #define ND_DEFAULTPRINT(ap, length) (*ndo->ndo_default_print)(ndo, ap, length)
 
 extern void ts_print(netdissect_options *, const struct timeval *);
@@ -513,7 +519,7 @@ extern void atm_print(netdissect_options *, u_int, u_int, u_int, const u_char *,
 extern void babel_print(netdissect_options *, const u_char *, u_int);
 extern void beep_print(netdissect_options *, const u_char *, u_int);
 extern void bfd_print(netdissect_options *, const u_char *, u_int, u_int);
-extern void bgp_print(netdissect_options *, const u_char *, int);
+extern void bgp_print(netdissect_options *, const u_char *, u_int);
 extern char *bgp_vpn_rd_print (netdissect_options *, const u_char *);
 extern void bootp_print(netdissect_options *, const u_char *, u_int);
 extern void calm_fast_print(netdissect_options *, const u_char *, u_int, const struct lladdr_info *);
@@ -589,10 +595,10 @@ extern void mpls_print(netdissect_options *, const u_char *, u_int);
 extern int mptcp_print(netdissect_options *, const u_char *, u_int, u_char);
 extern void msdp_print(netdissect_options *, const u_char *, u_int);
 extern void msnlb_print(netdissect_options *, const u_char *);
-extern void nbt_tcp_print(netdissect_options *, const u_char *, int);
-extern void nbt_udp137_print(netdissect_options *, const u_char *, int);
-extern void nbt_udp138_print(netdissect_options *, const u_char *, int);
-extern void netbeui_print(netdissect_options *, u_short, const u_char *, int);
+extern void nbt_tcp_print(netdissect_options *, const u_char *, u_int);
+extern void nbt_udp137_print(netdissect_options *, const u_char *, u_int);
+extern void nbt_udp138_print(netdissect_options *, const u_char *, u_int);
+extern void netbeui_print(netdissect_options *, u_short, const u_char *, u_int);
 extern void nfsreply_print(netdissect_options *, const u_char *, u_int, const u_char *);
 extern void nfsreply_noaddr_print(netdissect_options *, const u_char *, u_int, const u_char *);
 extern void nfsreq_noaddr_print(netdissect_options *, const u_char *, u_int, const u_char *);
@@ -605,8 +611,8 @@ extern void olsr_print(netdissect_options *, const u_char *, u_int, int);
 extern void openflow_print(netdissect_options *, const u_char *, const u_int);
 extern void ospf6_print(netdissect_options *, const u_char *, u_int);
 extern void ospf_print(netdissect_options *, const u_char *, u_int, const u_char *);
-extern int ospf_print_grace_lsa(netdissect_options *, const uint8_t *, u_int);
-extern int ospf_print_te_lsa(netdissect_options *, const uint8_t *, u_int);
+extern int ospf_print_grace_lsa(netdissect_options *, const u_char *, u_int);
+extern int ospf_print_te_lsa(netdissect_options *, const u_char *, u_int);
 extern void otv_print(netdissect_options *, const u_char *, u_int);
 extern void pgm_print(netdissect_options *, const u_char *, u_int, const u_char *);
 extern void pim_print(netdissect_options *, const u_char *, u_int, const u_char *);
@@ -631,8 +637,8 @@ extern void sctp_print(netdissect_options *, const u_char *, const u_char *, u_i
 extern void sflow_print(netdissect_options *, const u_char *, u_int);
 extern void sip_print(netdissect_options *, const u_char *, u_int);
 extern void slow_print(netdissect_options *, const u_char *, u_int);
-extern void smb_print_data(netdissect_options *, const unsigned char *, int);
-extern void smb_tcp_print(netdissect_options *, const u_char *, int);
+extern void smb_print_data(netdissect_options *, const u_char *, u_int);
+extern void smb_tcp_print(netdissect_options *, const u_char *, u_int);
 extern void smtp_print(netdissect_options *, const u_char *, u_int);
 extern int snap_print(netdissect_options *, const u_char *, u_int, u_int, const struct lladdr_info *, const struct lladdr_info *, u_int);
 extern void snmp_print(netdissect_options *, const u_char *, u_int);
@@ -653,7 +659,7 @@ extern void vrrp_print(netdissect_options *, const u_char *, u_int, const u_char
 extern void vtp_print(netdissect_options *, const u_char *, u_int);
 extern void vxlan_gpe_print(netdissect_options *ndo, const u_char *bp, u_int len);
 extern void vxlan_print(netdissect_options *, const u_char *, u_int);
-extern void wb_print(netdissect_options *, const void *, u_int);
+extern void wb_print(netdissect_options *, const u_char *, u_int);
 extern void zephyr_print(netdissect_options *, const u_char *, int);
 extern void zmtp1_print(netdissect_options *, const u_char *, u_int);
 extern void zmtp1_datagram_print(netdissect_options *, const u_char *, const u_int);
@@ -690,7 +696,8 @@ extern int decode_prefix6(netdissect_options *, const u_char *, u_int, char *, u
 
 extern void esp_print_decodesecret(netdissect_options *);
 extern int esp_print_decrypt_buffer_by_ikev2(netdissect_options *, int,
-					     u_char spii[8], u_char spir[8],
+					     const u_char spii[8],
+					     const u_char spir[8],
 					     const u_char *, const u_char *);
 
 #endif  /* netdissect_h */