diff options
| author | Denis Ovsienko <denis@ovsienko.info> | 2021-01-11 14:47:59 +0000 |
|---|---|---|
| committer | Denis Ovsienko <denis@ovsienko.info> | 2021-01-11 15:14:04 +0000 |
| commit | e6cf3b7fdbac28fde2b588692866cfdfb9a21818 (patch) | |
| tree | ca8a00667b4285f28e700ce5479d126125cf7713 | |
| parent | b05797e0dfa2a8369432b15a5ac4f8cc89c5fdb9 (diff) | |
| download | tcpdump-e6cf3b7fdbac28fde2b588692866cfdfb9a21818.tar.gz | |
EGP: Modernize packet parsing style.
Enable ND_LONGJMP_FROM_TCHECK. Report invalid packets as invalid.
| -rw-r--r-- | CHANGES | 2 | ||||
| -rw-r--r-- | print-egp.c | 27 |
2 files changed, 17 insertions, 12 deletions
@@ -2,7 +2,7 @@ Monthday, Month DD, YYYY by gharris and denis Summary for 5.0.0 tcpdump release (so far!) Source code: Use %zu when printing a sizeof to squelch compiler warnings - BOOTP, EIGRP, Geneve, L2TP, OLSR, PGM, RSVP: Modernize packet parsing style + BOOTP, EGP, EIGRP, Geneve, L2TP, OLSR, PGM, RSVP: Modernize packet parsing style EGP: Replace custom code with tok2str() EIGRP: Get the packet header fields right. diff --git a/print-egp.c b/print-egp.c index 28adf7de..bb93b025 100644 --- a/print-egp.c +++ b/print-egp.c @@ -28,6 +28,7 @@ #include "netdissect-stdinc.h" +#define ND_LONGJMP_FROM_TCHECK #include "netdissect.h" #include "addrtoname.h" #include "extract.h" @@ -179,7 +180,7 @@ egpnr_print(netdissect_options *ndo, /* Pickup host part of gateway address */ addr = 0; if (length < 4 - netlen) - goto trunc; + goto invalid; ND_TCHECK_LEN(cp, 4 - netlen); switch (netlen) { @@ -199,7 +200,7 @@ egpnr_print(netdissect_options *ndo, addr |= net; length -= 4 - netlen; if (length < 1) - goto trunc; + goto invalid; distances = GET_U_1(cp); cp++; length--; @@ -211,7 +212,7 @@ egpnr_print(netdissect_options *ndo, ND_PRINT("("); while (distances != 0) { if (length < 2) - goto trunc; + goto invalid; ND_PRINT("%sd%u:", comma, GET_U_1(cp)); cp++; comma = ", "; @@ -221,19 +222,19 @@ egpnr_print(netdissect_options *ndo, while (networks != 0) { /* Pickup network number */ if (length < 1) - goto trunc; + goto invalid; addr = ((uint32_t) GET_U_1(cp)) << 24; cp++; length--; if (IN_CLASSB(addr)) { if (length < 1) - goto trunc; + goto invalid; addr |= ((uint32_t) GET_U_1(cp)) << 16; cp++; length--; } else if (!IN_CLASSA(addr)) { if (length < 2) - goto trunc; + goto invalid; addr |= ((uint32_t) GET_U_1(cp)) << 16; cp++; addr |= ((uint32_t) GET_U_1(cp)) << 8; @@ -248,8 +249,8 @@ egpnr_print(netdissect_options *ndo, ND_PRINT(")"); } return; -trunc: - nd_print_trunc(ndo); +invalid: + nd_print_invalid(ndo); } void @@ -264,10 +265,11 @@ egp_print(netdissect_options *ndo, ndo->ndo_protocol = "egp"; egp = (const struct egp_packet *)bp; - if (length < sizeof(*egp) || !ND_TTEST_SIZE(egp)) { - nd_print_trunc(ndo); - return; + if (length < sizeof(*egp)) { + ND_PRINT(" packet length %u < %zu", length, sizeof(*egp)); + goto invalid; } + ND_TCHECK_SIZE(egp); version = GET_U_1(egp->egp_version); if (!ndo->ndo_vflag) { @@ -369,4 +371,7 @@ egp_print(netdissect_options *ndo, ND_PRINT(" %s", tok2str(egp_reasons_str, "[reason %u]", GET_BE_U_2(egp->egp_reason))); break; } + return; +invalid: + nd_print_invalid(ndo); } |