android clat service
This software provides the nat 4->6 translation needed for the "clat" part of
the 464xlat standard. It is needed for better IPv4 application support while
on an IPv6-only mobile network connection using 464xlat's nat64 (such as
T-Mobile's IPv6 trial).
A general diagram of how 464xlat works:
http://dan.drown.org/android/clat/Clat-Plat.png
Depends-on: I2392f8127dcd90d16b0f20ff31bcc5aa096db464
Change-Id: If2bc6916fc66fd4bca7cc241c83cfae839b82e15
Signed-off-by: Daniel Drown <dan-android@drown.org>
diff --git a/dump.c b/dump.c
new file mode 100644
index 0000000..3e4a6cc
--- /dev/null
+++ b/dump.c
@@ -0,0 +1,225 @@
+/*
+ * Copyright 2011 Daniel Drown
+ *
+ * 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.
+ *
+ * dump.c - print various headers for debugging
+ */
+#include <stdio.h>
+#include <stdint.h>
+
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <netinet/ip_icmp.h>
+#include <netinet/udp.h>
+#include <netinet/tcp.h>
+#include <netinet/ip6.h>
+#include <netinet/icmp6.h>
+#include <linux/icmp.h>
+
+#include "checksum.h"
+#include "clatd.h"
+#include "logging.h"
+
+/* print ip header */
+void dump_ip(struct iphdr *header) {
+ u_int16_t frag_flags;
+ char addrstr[INET6_ADDRSTRLEN];
+
+ frag_flags = ntohs(header->frag_off);
+
+ printf("IP packet\n");
+ printf("header_len = %x\n",header->ihl);
+ printf("version = %x\n",header->version);
+ printf("tos = %x\n",header->tos);
+ printf("tot_len = %x\n",ntohs(header->tot_len));
+ printf("id = %x\n",ntohs(header->id));
+ printf("frag: ");
+ if(frag_flags & IP_RF) {
+ printf("(RF) ");
+ }
+ if(frag_flags & IP_DF) {
+ printf("DF ");
+ }
+ if(frag_flags & IP_MF) {
+ printf("MF ");
+ }
+ printf("offset = %x\n",frag_flags & IP_OFFMASK);
+ printf("ttl = %x\n",header->ttl);
+ printf("protocol = %x\n",header->protocol);
+ printf("checksum = %x\n",ntohs(header->check));
+ inet_ntop(AF_INET, &header->saddr, addrstr, sizeof(addrstr));
+ printf("saddr = %s\n",addrstr);
+ inet_ntop(AF_INET, &header->daddr, addrstr, sizeof(addrstr));
+ printf("daddr = %s\n",addrstr);
+}
+
+/* print ip6 header */
+void dump_ip6(struct ip6_hdr *header) {
+ char addrstr[INET6_ADDRSTRLEN];
+
+ printf("ipv6\n");
+ printf("version = %x\n",header->ip6_vfc >> 4);
+ printf("traffic class = %x\n",header->ip6_flow >> 20);
+ printf("flow label = %x\n",ntohl(header->ip6_flow & 0x000fffff));
+ printf("payload len = %x\n",ntohs(header->ip6_plen));
+ printf("next header = %x\n",header->ip6_nxt);
+ printf("hop limit = %x\n",header->ip6_hlim);
+
+ inet_ntop(AF_INET6, &header->ip6_src, addrstr, sizeof(addrstr));
+ printf("source = %s\n",addrstr);
+
+ inet_ntop(AF_INET6, &header->ip6_dst, addrstr, sizeof(addrstr));
+ printf("dest = %s\n",addrstr);
+}
+
+/* print icmp header */
+void dump_icmp(struct icmphdr *icmp) {
+ printf("ICMP\n");
+
+ printf("icmp.type = %x ",icmp->type);
+ if(icmp->type == ICMP_ECHOREPLY) {
+ printf("echo reply");
+ } else if(icmp->type == ICMP_ECHO) {
+ printf("echo request");
+ } else {
+ printf("other");
+ }
+ printf("\n");
+ printf("icmp.code = %x\n",icmp->code);
+ printf("icmp.checksum = %x\n",ntohs(icmp->checksum));
+ if(icmp->type == ICMP_ECHOREPLY || icmp->type == ICMP_ECHO) {
+ printf("icmp.un.echo.id = %x\n",ntohs(icmp->un.echo.id));
+ printf("icmp.un.echo.sequence = %x\n",ntohs(icmp->un.echo.sequence));
+ }
+}
+
+/* print icmp6 header */
+void dump_icmp6(struct icmp6_hdr *icmp6) {
+ printf("ICMP6\n");
+ printf("type = %x",icmp6->icmp6_type);
+ if(icmp6->icmp6_type == ICMP6_ECHO_REQUEST) {
+ printf("(echo request)");
+ } else if(icmp6->icmp6_type == ICMP6_ECHO_REPLY) {
+ printf("(echo reply)");
+ }
+ printf("\n");
+ printf("code = %x\n",icmp6->icmp6_code);
+
+ printf("checksum = %x\n",icmp6->icmp6_cksum);
+
+ if((icmp6->icmp6_type == ICMP6_ECHO_REQUEST) || (icmp6->icmp6_type == ICMP6_ECHO_REPLY)) {
+ printf("icmp6_id = %x\n",icmp6->icmp6_id);
+ printf("icmp6_seq = %x\n",icmp6->icmp6_seq);
+ }
+}
+
+/* print udp header */
+void dump_udp_generic(const struct udphdr *udp, uint32_t temp_checksum, const char *payload, size_t payload_size) {
+ uint16_t my_checksum;
+
+ temp_checksum = ip_checksum_add(temp_checksum, udp, sizeof(struct udphdr));
+ temp_checksum = ip_checksum_add(temp_checksum, payload, payload_size);
+ my_checksum = ip_checksum_finish(temp_checksum);
+
+ printf("UDP\n");
+ printf("source = %x\n",ntohs(udp->source));
+ printf("dest = %x\n",ntohs(udp->dest));
+ printf("len = %x\n",ntohs(udp->len));
+ printf("check = %x (mine %x)\n",udp->check,my_checksum);
+}
+
+/* print ipv4/udp header */
+void dump_udp(const struct udphdr *udp, const struct iphdr *ip, const char *payload, size_t payload_size) {
+ uint32_t temp_checksum;
+ temp_checksum = ipv4_pseudo_header_checksum(0, ip);
+ dump_udp_generic(udp, temp_checksum, payload, payload_size);
+}
+
+/* print ipv6/udp header */
+void dump_udp6(const struct udphdr *udp, const struct ip6_hdr *ip6, const char *payload, size_t payload_size) {
+ uint32_t temp_checksum;
+ temp_checksum = ipv6_pseudo_header_checksum(0, ip6);
+ dump_udp_generic(udp, temp_checksum, payload, payload_size);
+}
+
+/* print tcp header */
+void dump_tcp_generic(const struct tcphdr *tcp, const char *options, size_t options_size, uint32_t temp_checksum, const char *payload, size_t payload_size) {
+ uint16_t my_checksum;
+
+ temp_checksum = ip_checksum_add(temp_checksum, tcp, sizeof(struct tcphdr));
+ if(options) {
+ temp_checksum = ip_checksum_add(temp_checksum, options, options_size);
+ }
+ temp_checksum = ip_checksum_add(temp_checksum, payload, payload_size);
+ my_checksum = ip_checksum_finish(temp_checksum);
+
+ printf("TCP\n");
+ printf("source = %x\n",ntohs(tcp->source));
+ printf("dest = %x\n",ntohs(tcp->dest));
+ printf("seq = %x\n",ntohl(tcp->seq));
+ printf("ack = %x\n",ntohl(tcp->ack_seq));
+ printf("d_off = %x\n",tcp->doff);
+ printf("res1 = %x\n",tcp->res1);
+#ifdef __BIONIC__
+ printf("CWR = %x\n",tcp->cwr);
+ printf("ECE = %x\n",tcp->ece);
+#else
+ printf("CWR/ECE = %x\n",tcp->res2);
+#endif
+ printf("urg = %x ack = %x psh = %x rst = %x syn = %x fin = %x\n",
+ tcp->urg, tcp->ack, tcp->psh, tcp->rst, tcp->syn, tcp->fin);
+ printf("window = %x\n",ntohs(tcp->window));
+ printf("check = %x [mine %x]\n",tcp->check,my_checksum);
+ printf("urgent = %x\n",tcp->urg_ptr);
+
+ if(options) {
+ size_t i;
+
+ printf("options: ");
+ for(i=0; i<options_size; i++) {
+ printf("%x ",*(options+i));
+ }
+ printf("\n");
+ }
+}
+
+/* print ipv4/tcp header */
+void dump_tcp(const struct tcphdr *tcp, const struct iphdr *ip, const char *payload, size_t payload_size, const char *options, size_t options_size) {
+ uint32_t temp_checksum;
+
+ temp_checksum = ipv4_pseudo_header_checksum(0, ip);
+ dump_tcp_generic(tcp, options, options_size, temp_checksum, payload, payload_size);
+}
+
+/* print ipv6/tcp header */
+void dump_tcp6(const struct tcphdr *tcp, const struct ip6_hdr *ip6, const char *payload, size_t payload_size, const char *options, size_t options_size) {
+ uint32_t temp_checksum;
+
+ temp_checksum = ipv6_pseudo_header_checksum(0, ip6);
+ dump_tcp_generic(tcp, options, options_size, temp_checksum, payload, payload_size);
+}
+
+/* generic hex dump */
+void logcat_hexdump(const char *info, const char *data, size_t len) {
+ char output[PACKETLEN*2+1];
+ size_t i;
+
+ for(i = 0; i < len && i < PACKETLEN; i++) {
+ snprintf(output + i*2, 3, "%02x", (uint8_t)data[i]);
+ }
+ output[len*2+2] = '\0';
+
+ logmsg(ANDROID_LOG_WARN,"info %s len %d data %s", info, len, output);
+}
