diff options
Diffstat (limited to 'print-ip6.c')
| -rw-r--r-- | print-ip6.c | 85 |
1 files changed, 52 insertions, 33 deletions
diff --git a/print-ip6.c b/print-ip6.c index 525a284e..2f1183c0 100644 --- a/print-ip6.c +++ b/print-ip6.c @@ -231,11 +231,12 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length) u_int total_advance; const u_char *cp; uint32_t payload_len; - uint8_t nh; + uint8_t ph, nh; int fragmented = 0; u_int flow; int found_extension_header; int found_jumbo; + int found_hbh; ndo->ndo_protocol = "ip6"; ip6 = (const struct ip6_hdr *)bp; @@ -246,12 +247,12 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length) return; } - if (!ndo->ndo_eflag) - ND_PRINT("IP6 "); + if (!ndo->ndo_eflag) + ND_PRINT("IP6 "); if (IP6_VERSION(ip6) != 6) { - ND_PRINT("version error: %u != 6", IP6_VERSION(ip6)); - return; + ND_PRINT("version error: %u != 6", IP6_VERSION(ip6)); + return; } payload_len = GET_BE_U_2(ip6->ip6_plen); @@ -285,35 +286,31 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length) } else len = length + sizeof(struct ip6_hdr); - nh = GET_U_1(ip6->ip6_nxt); - if (ndo->ndo_vflag) { - flow = GET_BE_U_4(ip6->ip6_flow); - ND_PRINT("("); -#if 0 - /* rfc1883 */ - if (flow & 0x0f000000) - ND_PRINT("pri 0x%02x, ", (flow & 0x0f000000) >> 24); - if (flow & 0x00ffffff) - ND_PRINT("flowlabel 0x%06x, ", flow & 0x00ffffff); -#else - /* RFC 2460 */ - if (flow & 0x0ff00000) - ND_PRINT("class 0x%02x, ", (flow & 0x0ff00000) >> 20); - if (flow & 0x000fffff) - ND_PRINT("flowlabel 0x%05x, ", flow & 0x000fffff); -#endif - - ND_PRINT("hlim %u, next-header %s (%u) payload length: %u) ", - GET_U_1(ip6->ip6_hlim), - tok2str(ipproto_values,"unknown",nh), - nh, - payload_len); - } + ph = 255; + nh = GET_U_1(ip6->ip6_nxt); + if (ndo->ndo_vflag) { + flow = GET_BE_U_4(ip6->ip6_flow); + ND_PRINT("("); + /* RFC 2460 */ + if (flow & 0x0ff00000) + ND_PRINT("class 0x%02x, ", (flow & 0x0ff00000) >> 20); + if (flow & 0x000fffff) + ND_PRINT("flowlabel 0x%05x, ", flow & 0x000fffff); + + ND_PRINT("hlim %u, next-header %s (%u) payload length: %u) ", + GET_U_1(ip6->ip6_hlim), + tok2str(ipproto_values,"unknown",nh), + nh, + payload_len); + } /* * Cut off the snapshot length to the end of the IP payload. */ - nd_push_snapend(ndo, bp + len); + if (!nd_push_snaplen(ndo, bp, len)) { + (*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC, + "%s: can't push snaplen on buffer stack", __func__); + } cp = (const u_char *)ip6; advance = sizeof(struct ip6_hdr); @@ -321,6 +318,7 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length) /* Process extension headers */ found_extension_header = 0; found_jumbo = 0; + found_hbh = 0; while (cp < ndo->ndo_snapend && advance > 0) { if (len < (u_int)advance) goto trunc; @@ -338,12 +336,32 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length) switch (nh) { case IPPROTO_HOPOPTS: + /* + * The Hop-by-Hop Options header, when present, + * must immediately follow the IPv6 header (RFC 8200) + */ + if (found_hbh == 1) { + ND_PRINT("[The Hop-by-Hop Options header was already found]"); + nd_print_invalid(ndo); + return; + } + if (ph != 255) { + ND_PRINT("[The Hop-by-Hop Options header don't follow the IPv6 header]"); + nd_print_invalid(ndo); + return; + } advance = hbhopt_process(ndo, cp, &found_jumbo, &payload_len); + if (payload_len == 0 && found_jumbo == 0) { + ND_PRINT("[No valid Jumbo Payload Hop-by-Hop option found]"); + nd_print_invalid(ndo); + return; + } if (advance < 0) { nd_pop_packet_info(ndo); return; } found_extension_header = 1; + found_hbh = 1; nh = GET_U_1(cp); break; @@ -421,7 +439,7 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length) if (length < len) ND_PRINT("truncated-ip6 - %u bytes missing!", len - length); - nd_change_snapend(ndo, bp + len); + nd_change_snaplen(ndo, bp, len); /* * Now subtract the length of the IPv6 @@ -446,7 +464,7 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length) goto trunc; /* - * OK, we didn't see any extnesion + * OK, we didn't see any extension * header, but that means we have * no payload, so set the length * to the IPv6 header length, @@ -454,7 +472,7 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length) * accordingly. */ len = sizeof(struct ip6_hdr); - nd_change_snapend(ndo, bp + len); + nd_change_snaplen(ndo, bp, len); /* * Now subtract the length of @@ -471,6 +489,7 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length) nd_pop_packet_info(ndo); return; } + ph = nh; /* ndo_protocol reassignment after xxx_print() calls */ ndo->ndo_protocol = "ip6"; |