1 /*
2 * Oracle
3 */
4
5 /* \summary: Per-Packet Information (DLT_PPI) printer */
6
7 /* Specification:
8 * Per-Packet Information Header Specification - Version 1.0.7
9 * https://web.archive.org/web/20160328114748/http://www.cacetech.com/documents/PPI%20Header%20format%201.0.7.pdf
10 */
11
12 #include <config.h>
13
14 #include "netdissect-stdinc.h"
15
16 #include "netdissect.h"
17 #include "extract.h"
18
19
20 typedef struct ppi_header {
21 nd_uint8_t ppi_ver; /* Version. Currently 0 */
22 nd_uint8_t ppi_flags; /* Flags. */
23 nd_uint16_t ppi_len; /* Length of entire message, including
24 * this header and TLV payload. */
25 nd_uint32_t ppi_dlt; /* Data Link Type of the captured
26 * packet data. */
27 } ppi_header_t;
28
29 #define PPI_HDRLEN 8
30
31 #ifdef DLT_PPI
32
33 static void
ppi_header_print(netdissect_options * ndo,const u_char * bp,u_int length)34 ppi_header_print(netdissect_options *ndo, const u_char *bp, u_int length)
35 {
36 const ppi_header_t *hdr;
37 uint16_t len;
38 uint32_t dlt;
39 const char *dltname;
40
41 hdr = (const ppi_header_t *)bp;
42
43 len = GET_LE_U_2(hdr->ppi_len);
44 dlt = GET_LE_U_4(hdr->ppi_dlt);
45 dltname = pcap_datalink_val_to_name(dlt);
46
47 if (!ndo->ndo_qflag) {
48 ND_PRINT("V.%u DLT %s (%u) len %u", GET_U_1(hdr->ppi_ver),
49 (dltname != NULL ? dltname : "UNKNOWN"), dlt,
50 len);
51 } else {
52 ND_PRINT("%s", (dltname != NULL ? dltname : "UNKNOWN"));
53 }
54
55 ND_PRINT(", length %u: ", length);
56 }
57
58 /*
59 * This is the top level routine of the printer. 'p' points
60 * to the ether header of the packet, 'h->ts' is the timestamp,
61 * 'h->len' is the length of the packet off the wire, and 'h->caplen'
62 * is the number of bytes actually captured.
63 */
64 void
ppi_if_print(netdissect_options * ndo,const struct pcap_pkthdr * h,const u_char * p)65 ppi_if_print(netdissect_options *ndo,
66 const struct pcap_pkthdr *h, const u_char *p)
67 {
68 if_printer printer;
69 const ppi_header_t *hdr;
70 u_int caplen = h->caplen;
71 u_int length = h->len;
72 uint16_t len;
73 uint32_t dlt;
74 uint32_t hdrlen;
75 struct pcap_pkthdr nhdr;
76
77 ndo->ndo_protocol = "ppi";
78 if (caplen < sizeof(ppi_header_t)) {
79 nd_print_trunc(ndo);
80 ndo->ndo_ll_hdr_len += caplen;
81 return;
82 }
83
84 hdr = (const ppi_header_t *)p;
85 len = GET_LE_U_2(hdr->ppi_len);
86 if (len < sizeof(ppi_header_t) || len > 65532) {
87 /* It MUST be between 8 and 65,532 inclusive (spec 3.1.3) */
88 ND_PRINT(" [length %u < %zu or > 65532]", len,
89 sizeof(ppi_header_t));
90 nd_print_invalid(ndo);
91 ndo->ndo_ll_hdr_len += caplen;
92 return;
93 }
94 if (caplen < len) {
95 /*
96 * If we don't have the entire PPI header, don't
97 * bother.
98 */
99 nd_print_trunc(ndo);
100 ndo->ndo_ll_hdr_len += caplen;
101 return;
102 }
103 dlt = GET_LE_U_4(hdr->ppi_dlt);
104
105 if (ndo->ndo_eflag)
106 ppi_header_print(ndo, p, length);
107
108 length -= len;
109 caplen -= len;
110 p += len;
111
112 printer = lookup_printer(dlt);
113 if (printer != NULL) {
114 nhdr = *h;
115 nhdr.caplen = caplen;
116 nhdr.len = length;
117 printer(ndo, &nhdr, p);
118 hdrlen = ndo->ndo_ll_hdr_len;
119 } else {
120 if (!ndo->ndo_eflag)
121 ppi_header_print(ndo, (const u_char *)hdr, length + len);
122
123 if (!ndo->ndo_suppress_default_print)
124 ND_DEFAULTPRINT(p, caplen);
125 hdrlen = 0;
126 }
127 ndo->ndo_ll_hdr_len += len + hdrlen;
128 }
129 #endif /* DLT_PPI */
130