diff options
Diffstat (limited to 'icmp.c')
| -rw-r--r-- | icmp.c | 177 |
1 files changed, 0 insertions, 177 deletions
@@ -1,177 +0,0 @@ -/* - * Copyright (C) 2013 The Android Open Source Project - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - * - * icmp.c - convenience functions for translating ICMP and ICMPv6 packets. - */ - -#include <linux/icmp.h> -#include <netinet/icmp6.h> -#include <netinet/in.h> -#include <netinet/ip_icmp.h> - -#include "icmp.h" -#include "logging.h" - -/* function: icmp_guess_ttl - * Guesses the number of hops a received packet has traversed based on its TTL. - * ttl - the ttl of the received packet. - */ -uint8_t icmp_guess_ttl(uint8_t ttl) { - if (ttl > 128) { - return 255 - ttl; - } else if (ttl > 64) { - return 128 - ttl; - } else if (ttl > 32) { - return 64 - ttl; - } else { - return 32 - ttl; - } -} - -/* function: is_icmp_error - * Determines whether an ICMP type is an error message. - * type: the ICMP type - */ -int is_icmp_error(uint8_t type) { return type == 3 || type == 11 || type == 12; } - -/* function: is_icmp6_error - * Determines whether an ICMPv6 type is an error message. - * type: the ICMPv6 type - */ -int is_icmp6_error(uint8_t type) { return type < 128; } - -/* function: icmp_to_icmp6_type - * Maps ICMP types to ICMPv6 types. Partial implementation of RFC 6145, section 4.2. - * type - the ICMPv6 type - */ -uint8_t icmp_to_icmp6_type(uint8_t type, uint8_t code) { - switch (type) { - case ICMP_ECHO: - return ICMP6_ECHO_REQUEST; - - case ICMP_ECHOREPLY: - return ICMP6_ECHO_REPLY; - - case ICMP_TIME_EXCEEDED: - return ICMP6_TIME_EXCEEDED; - - case ICMP_DEST_UNREACH: - // These two types need special translation which we don't support yet. - if (code != ICMP_UNREACH_PROTOCOL && code != ICMP_UNREACH_NEEDFRAG) { - return ICMP6_DST_UNREACH; - } - } - - // We don't understand this ICMP type. Return parameter problem so the caller will bail out. - logmsg_dbg(ANDROID_LOG_DEBUG, "icmp_to_icmp6_type: unhandled ICMP type %d", type); - return ICMP6_PARAM_PROB; -} - -/* function: icmp_to_icmp6_code - * Maps ICMP codes to ICMPv6 codes. Partial implementation of RFC 6145, section 4.2. - * type - the ICMP type - * code - the ICMP code - */ -uint8_t icmp_to_icmp6_code(uint8_t type, uint8_t code) { - switch (type) { - case ICMP_ECHO: - case ICMP_ECHOREPLY: - return 0; - - case ICMP_TIME_EXCEEDED: - return code; - - case ICMP_DEST_UNREACH: - switch (code) { - case ICMP_UNREACH_NET: - case ICMP_UNREACH_HOST: - return ICMP6_DST_UNREACH_NOROUTE; - - case ICMP_UNREACH_PORT: - return ICMP6_DST_UNREACH_NOPORT; - - case ICMP_UNREACH_NET_PROHIB: - case ICMP_UNREACH_HOST_PROHIB: - case ICMP_UNREACH_FILTER_PROHIB: - case ICMP_UNREACH_PRECEDENCE_CUTOFF: - return ICMP6_DST_UNREACH_ADMIN; - - // Otherwise, we don't understand this ICMP type/code combination. Fall through. - } - } - logmsg_dbg(ANDROID_LOG_DEBUG, "icmp_to_icmp6_code: unhandled ICMP type/code %d/%d", type, code); - return 0; -} - -/* function: icmp6_to_icmp_type - * Maps ICMPv6 types to ICMP types. Partial implementation of RFC 6145, section 5.2. - * type - the ICMP type - */ -uint8_t icmp6_to_icmp_type(uint8_t type, uint8_t code) { - switch (type) { - case ICMP6_ECHO_REQUEST: - return ICMP_ECHO; - - case ICMP6_ECHO_REPLY: - return ICMP_ECHOREPLY; - - case ICMP6_DST_UNREACH: - return ICMP_DEST_UNREACH; - - case ICMP6_TIME_EXCEEDED: - return ICMP_TIME_EXCEEDED; - } - - // We don't understand this ICMP type. Return parameter problem so the caller will bail out. - logmsg_dbg(ANDROID_LOG_DEBUG, "icmp6_to_icmp_type: unhandled ICMP type/code %d/%d", type, code); - return ICMP_PARAMETERPROB; -} - -/* function: icmp6_to_icmp_code - * Maps ICMPv6 codes to ICMP codes. Partial implementation of RFC 6145, section 5.2. - * type - the ICMPv6 type - * code - the ICMPv6 code - */ -uint8_t icmp6_to_icmp_code(uint8_t type, uint8_t code) { - switch (type) { - case ICMP6_ECHO_REQUEST: - case ICMP6_ECHO_REPLY: - case ICMP6_TIME_EXCEEDED: - return code; - - case ICMP6_DST_UNREACH: - switch (code) { - case ICMP6_DST_UNREACH_NOROUTE: - return ICMP_UNREACH_HOST; - - case ICMP6_DST_UNREACH_ADMIN: - return ICMP_UNREACH_HOST_PROHIB; - - case ICMP6_DST_UNREACH_BEYONDSCOPE: - return ICMP_UNREACH_HOST; - - case ICMP6_DST_UNREACH_ADDR: - return ICMP_HOST_UNREACH; - - case ICMP6_DST_UNREACH_NOPORT: - return ICMP_UNREACH_PORT; - - // Otherwise, we don't understand this ICMPv6 type/code combination. Fall through. - } - } - - logmsg_dbg(ANDROID_LOG_DEBUG, "icmp6_to_icmp_code: unhandled ICMP type/code %d/%d", type, code); - return 0; -} |