X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/dbf0433fef377d3739e94b881cdd540c5f988a98..570bb7d1f8f87be048e8299a4c38b82b092a9b7b:/print-icmp.c diff --git a/print-icmp.c b/print-icmp.c index 6642c990..074d9377 100644 --- a/print-icmp.c +++ b/print-icmp.c @@ -86,9 +86,6 @@ struct icmp { #define icmp_data icmp_dun.id_data }; -#define ICMP_EXT_EXTRACT_VERSION(x) (((x)&0xf0)>>4) -#define ICMP_MPLS_EXT_VERSION 2 - /* * Lower bounds on packet lengths for various types. * For the error advice packets must first insure that the @@ -188,11 +185,6 @@ struct icmp { #define ICMP_UNREACH_PRECEDENCE_CUTOFF 15 /* precedence cutoff */ #endif -/* rfc4950 */ -#define MPLS_STACK_ENTRY_OBJECT_CLASS 1 -/* rfc5837 */ -#define INTERFACE_INFORMATION_OBJECT_CLASS 2 - /* Most of the icmp types */ static const struct tok icmp2str[] = { { ICMP_ECHOREPLY, "echo reply" }, @@ -226,13 +218,17 @@ struct id_rdiscovery { }; /* - * draft-bonica-internet-icmp-08 + * RFC 4884 - Extended ICMP to Support Multi-Part Messages + * + * This is a general extension mechanism, based on the mechanism + * in draft-bonica-icmp-mpls-02 ICMP Extensions for MultiProtocol + * Label Switching. * * The Destination Unreachable, Time Exceeded * and Parameter Problem messages are slightly changed as per - * the above draft. A new Length field gets added to give + * the above RFC. A new Length field gets added to give * the caller an idea about the length of the piggybacked - * IP packet before the MPLS extension header starts. + * IP packet before the extension header starts. * * The Length field represents length of the padded "original datagram" * field measured in 32-bit words. @@ -264,6 +260,32 @@ struct icmp_ext_t { nd_byte icmp_ext_data[1]; }; +/* + * Extract version from the first octet of icmp_ext_version_res. + */ +#define ICMP_EXT_EXTRACT_VERSION(x) (((x)&0xf0)>>4) + +/* + * Current version. + */ +#define ICMP_EXT_VERSION 2 + +/* + * Extension object class numbers. + * + * Class 1 dates back to draft-bonica-icmp-mpls-02. + * + * Class 2 was used for an "Extended Payload Object Class", which + * contained bytes of the payload beyond the first 128 bytes, in + * draft-bonica-icmp-mpls-02; it was reassigned to an "Interface + * Information Object" in RFC 5837. + */ + +/* rfc4950 */ +#define MPLS_STACK_ENTRY_OBJECT_CLASS 1 +/* rfc5837 */ +#define INTERFACE_INFORMATION_OBJECT_CLASS 2 + struct icmp_multipart_ext_object_header_t { nd_uint16_t length; nd_uint8_t class_num; @@ -282,7 +304,7 @@ static const struct tok icmp_interface_identification_role_values[] = { { 1, "the sub-IP component of an IP interface upon which a datagram arrived"}, { 2, "the IP interface through which the datagram would have been forwarded had it been forwardable"}, { 3, "the IP next hop to which the datagram would have been forwarded"}, - { 0, NULL } + { 0, NULL } }; /* @@ -748,7 +770,7 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char * * Sanity checking of the header. */ if (ICMP_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)) != - ICMP_MPLS_EXT_VERSION) { + ICMP_EXT_VERSION) { ND_PRINT(" packet not supported"); return; } @@ -806,62 +828,76 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char * break; case INTERFACE_INFORMATION_OBJECT_CLASS: - /* - - Ctype in a INTERFACE_INFORMATION_OBJECT_CLASS object: - - Bit 0 1 2 3 4 5 6 7 - +-------+-------+-------+-------+-------+-------+-------+-------+ - | Interface Role| Rsvd1 | Rsvd2 |ifIndex| IPAddr| name | MTU | - +-------+-------+-------+-------+-------+-------+-------+-------+ - - */ - interface_role = (obj_ctype & 0xc0) >> 6; - if_index_flag = (obj_ctype & 0x8) >> 3; - ipaddr_flag = (obj_ctype & 0x4) >> 2; - name_flag = (obj_ctype & 0x2) >> 1; - mtu_flag = (obj_ctype & 0x1); - - ND_PRINT("\n\t\t This object describes %s", - tok2str(icmp_interface_identification_role_values,"an unknown interface role",interface_role)); - - offset = obj_tptr; - - if (if_index_flag) { - ND_PRINT("\n\t\t Interface Index: %u", GET_BE_U_4(offset)); - offset += 4; - } - - if (ipaddr_flag) { - ND_PRINT("\n\t\t IP Address sub-object: "); - ipaddr_subobj = (const struct icmp_interface_identification_ipaddr_subobject_t *) offset; - switch (GET_BE_U_2(ipaddr_subobj->afi)) { - case 1: - ND_PRINT("%s", GET_IPADDR_STRING(ipaddr_subobj->ip_addr)); - offset += 4; - break; - case 2: - ND_PRINT("%s", GET_IP6ADDR_STRING(ipaddr_subobj->ip_addr)); - offset += 16; - break; - default: - ND_PRINT("Unknown Address Family Identifier"); - return; - } - offset += 4; - } - - if (name_flag) { - ifname_subobj = (const struct icmp_interface_identification_ifname_subobject_t *) offset; - ND_PRINT("\n\t\t Interface Name: %.*s", GET_U_1(ifname_subobj->length), ifname_subobj->if_name); - offset += 1 + GET_U_1(ifname_subobj->length); - } - if (mtu_flag) { - ND_PRINT("\n\t\t MTU: %u", GET_BE_U_4(offset)); - offset += 4; - } - - break; + /* + Ctype in a INTERFACE_INFORMATION_OBJECT_CLASS object: + + Bit 0 1 2 3 4 5 6 7 + +-------+-------+-------+-------+-------+-------+-------+-------+ + | Interface Role| Rsvd1 | Rsvd2 |ifIndex| IPAddr| name | MTU | + +-------+-------+-------+-------+-------+-------+-------+-------+ + */ + interface_role = (obj_ctype & 0xc0) >> 6; + if_index_flag = (obj_ctype & 0x8) >> 3; + ipaddr_flag = (obj_ctype & 0x4) >> 2; + name_flag = (obj_ctype & 0x2) >> 1; + mtu_flag = (obj_ctype & 0x1); + + ND_PRINT("\n\t\t This object describes %s", + tok2str(icmp_interface_identification_role_values, + "an unknown interface role",interface_role)); + + offset = obj_tptr; + + if (if_index_flag) { + ND_PRINT("\n\t\t Interface Index: %u", GET_BE_U_4(offset)); + offset += 4; + } + if (ipaddr_flag) { + ND_PRINT("\n\t\t IP Address sub-object: "); + ipaddr_subobj = (const struct icmp_interface_identification_ipaddr_subobject_t *) offset; + switch (GET_BE_U_2(ipaddr_subobj->afi)) { + case 1: + ND_PRINT("%s", GET_IPADDR_STRING(ipaddr_subobj->ip_addr)); + offset += 4; + break; + case 2: + ND_PRINT("%s", GET_IP6ADDR_STRING(ipaddr_subobj->ip_addr)); + offset += 16; + break; + default: + ND_PRINT("Unknown Address Family Identifier"); + return; + } + offset += 4; + } + if (name_flag) { + uint8_t inft_name_length_field; + + ifname_subobj = (const struct icmp_interface_identification_ifname_subobject_t *) offset; + inft_name_length_field = GET_U_1(ifname_subobj->length); + ND_PRINT("\n\t\t Interface Name"); + if (inft_name_length_field % 4 != 0) { + ND_PRINT(" [length %u != N x 4]", inft_name_length_field); + nd_print_invalid(ndo); + offset += inft_name_length_field; + break; + } + if (inft_name_length_field > 64) { + ND_PRINT(" [length %u > 64]", inft_name_length_field); + nd_print_invalid(ndo); + offset += inft_name_length_field; + break; + } + ND_PRINT(", length %u: ", inft_name_length_field); + nd_printjnp(ndo, ifname_subobj->if_name, + inft_name_length_field - 1); + offset += inft_name_length_field; + } + if (mtu_flag) { + ND_PRINT("\n\t\t MTU: %u", GET_BE_U_4(offset)); + offset += 4; + } + break; default: print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen);