1 /*
2  * Copyright 2011 Daniel Drown
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  * http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  *
16  * dump.c - print various headers for debugging
17  */
18 #include <stdint.h>
19 #include <stdio.h>
20 #include <stdlib.h>
21 
22 #include <arpa/inet.h>
23 #include <linux/icmp.h>
24 #include <netinet/icmp6.h>
25 #include <netinet/in.h>
26 #include <netinet/ip.h>
27 #include <netinet/ip6.h>
28 #include <netinet/ip_icmp.h>
29 #include <netinet/tcp.h>
30 #include <netinet/udp.h>
31 
32 #include "netutils/checksum.h"
33 
34 #include "clatd.h"
35 #include "debug.h"
36 #include "logging.h"
37 
38 #if CLAT_DEBUG
39 
40 /* print ip header */
dump_ip(struct iphdr * header)41 void dump_ip(struct iphdr *header) {
42   u_int16_t frag_flags;
43   char addrstr[INET6_ADDRSTRLEN];
44 
45   frag_flags = ntohs(header->frag_off);
46 
47   printf("IP packet\n");
48   printf("header_len = %x\n", header->ihl);
49   printf("version = %x\n", header->version);
50   printf("tos = %x\n", header->tos);
51   printf("tot_len = %x\n", ntohs(header->tot_len));
52   printf("id = %x\n", ntohs(header->id));
53   printf("frag: ");
54   if (frag_flags & IP_RF) {
55     printf("(RF) ");
56   }
57   if (frag_flags & IP_DF) {
58     printf("DF ");
59   }
60   if (frag_flags & IP_MF) {
61     printf("MF ");
62   }
63   printf("offset = %x\n", frag_flags & IP_OFFMASK);
64   printf("ttl = %x\n", header->ttl);
65   printf("protocol = %x\n", header->protocol);
66   printf("checksum = %x\n", ntohs(header->check));
67   inet_ntop(AF_INET, &header->saddr, addrstr, sizeof(addrstr));
68   printf("saddr = %s\n", addrstr);
69   inet_ntop(AF_INET, &header->daddr, addrstr, sizeof(addrstr));
70   printf("daddr = %s\n", addrstr);
71 }
72 
73 /* print ip6 header */
dump_ip6(struct ip6_hdr * header)74 void dump_ip6(struct ip6_hdr *header) {
75   char addrstr[INET6_ADDRSTRLEN];
76 
77   printf("ipv6\n");
78   printf("version = %x\n", header->ip6_vfc >> 4);
79   printf("traffic class = %x\n", header->ip6_flow >> 20);
80   printf("flow label = %x\n", ntohl(header->ip6_flow & 0x000fffff));
81   printf("payload len = %x\n", ntohs(header->ip6_plen));
82   printf("next header = %x\n", header->ip6_nxt);
83   printf("hop limit = %x\n", header->ip6_hlim);
84 
85   inet_ntop(AF_INET6, &header->ip6_src, addrstr, sizeof(addrstr));
86   printf("source = %s\n", addrstr);
87 
88   inet_ntop(AF_INET6, &header->ip6_dst, addrstr, sizeof(addrstr));
89   printf("dest = %s\n", addrstr);
90 }
91 
92 /* print icmp header */
dump_icmp(struct icmphdr * icmp)93 void dump_icmp(struct icmphdr *icmp) {
94   printf("ICMP\n");
95 
96   printf("icmp.type = %x ", icmp->type);
97   if (icmp->type == ICMP_ECHOREPLY) {
98     printf("echo reply");
99   } else if (icmp->type == ICMP_ECHO) {
100     printf("echo request");
101   } else {
102     printf("other");
103   }
104   printf("\n");
105   printf("icmp.code = %x\n", icmp->code);
106   printf("icmp.checksum = %x\n", ntohs(icmp->checksum));
107   if (icmp->type == ICMP_ECHOREPLY || icmp->type == ICMP_ECHO) {
108     printf("icmp.un.echo.id = %x\n", ntohs(icmp->un.echo.id));
109     printf("icmp.un.echo.sequence = %x\n", ntohs(icmp->un.echo.sequence));
110   }
111 }
112 
113 /* print icmp6 header */
dump_icmp6(struct icmp6_hdr * icmp6)114 void dump_icmp6(struct icmp6_hdr *icmp6) {
115   printf("ICMP6\n");
116   printf("type = %x", icmp6->icmp6_type);
117   if (icmp6->icmp6_type == ICMP6_ECHO_REQUEST) {
118     printf("(echo request)");
119   } else if (icmp6->icmp6_type == ICMP6_ECHO_REPLY) {
120     printf("(echo reply)");
121   }
122   printf("\n");
123   printf("code = %x\n", icmp6->icmp6_code);
124 
125   printf("checksum = %x\n", icmp6->icmp6_cksum);
126 
127   if ((icmp6->icmp6_type == ICMP6_ECHO_REQUEST) || (icmp6->icmp6_type == ICMP6_ECHO_REPLY)) {
128     printf("icmp6_id = %x\n", icmp6->icmp6_id);
129     printf("icmp6_seq = %x\n", icmp6->icmp6_seq);
130   }
131 }
132 
133 /* print udp header */
dump_udp_generic(const struct udphdr * udp,uint32_t temp_checksum,const uint8_t * payload,size_t payload_size)134 void dump_udp_generic(const struct udphdr *udp, uint32_t temp_checksum, const uint8_t *payload,
135                       size_t payload_size) {
136   uint16_t my_checksum;
137 
138   temp_checksum = ip_checksum_add(temp_checksum, udp, sizeof(struct udphdr));
139   temp_checksum = ip_checksum_add(temp_checksum, payload, payload_size);
140   my_checksum   = ip_checksum_finish(temp_checksum);
141 
142   printf("UDP\n");
143   printf("source = %x\n", ntohs(udp->source));
144   printf("dest = %x\n", ntohs(udp->dest));
145   printf("len = %x\n", ntohs(udp->len));
146   printf("check = %x (mine %x)\n", udp->check, my_checksum);
147 }
148 
149 /* print ipv4/udp header */
dump_udp(const struct udphdr * udp,const struct iphdr * ip,const uint8_t * payload,size_t payload_size)150 void dump_udp(const struct udphdr *udp, const struct iphdr *ip, const uint8_t *payload,
151               size_t payload_size) {
152   uint32_t temp_checksum;
153   temp_checksum = ipv4_pseudo_header_checksum(ip, sizeof(*udp) + payload_size);
154   dump_udp_generic(udp, temp_checksum, payload, payload_size);
155 }
156 
157 /* print ipv6/udp header */
dump_udp6(const struct udphdr * udp,const struct ip6_hdr * ip6,const uint8_t * payload,size_t payload_size)158 void dump_udp6(const struct udphdr *udp, const struct ip6_hdr *ip6, const uint8_t *payload,
159                size_t payload_size) {
160   uint32_t temp_checksum;
161   temp_checksum = ipv6_pseudo_header_checksum(ip6, sizeof(*udp) + payload_size, IPPROTO_UDP);
162   dump_udp_generic(udp, temp_checksum, payload, payload_size);
163 }
164 
165 /* print tcp header */
dump_tcp_generic(const struct tcphdr * tcp,const uint8_t * options,size_t options_size,uint32_t temp_checksum,const uint8_t * payload,size_t payload_size)166 void dump_tcp_generic(const struct tcphdr *tcp, const uint8_t *options, size_t options_size,
167                       uint32_t temp_checksum, const uint8_t *payload, size_t payload_size) {
168   uint16_t my_checksum;
169 
170   temp_checksum = ip_checksum_add(temp_checksum, tcp, sizeof(struct tcphdr));
171   if (options) {
172     temp_checksum = ip_checksum_add(temp_checksum, options, options_size);
173   }
174   temp_checksum = ip_checksum_add(temp_checksum, payload, payload_size);
175   my_checksum   = ip_checksum_finish(temp_checksum);
176 
177   printf("TCP\n");
178   printf("source = %x\n", ntohs(tcp->source));
179   printf("dest = %x\n", ntohs(tcp->dest));
180   printf("seq = %x\n", ntohl(tcp->seq));
181   printf("ack = %x\n", ntohl(tcp->ack_seq));
182   printf("d_off = %x\n", tcp->doff);
183   printf("res1 = %x\n", tcp->res1);
184 #ifdef __BIONIC__
185   printf("CWR = %x\n", tcp->cwr);
186   printf("ECE = %x\n", tcp->ece);
187 #else
188   printf("CWR/ECE = %x\n", tcp->res2);
189 #endif
190   printf("urg = %x  ack = %x  psh = %x  rst = %x  syn = %x  fin = %x\n", tcp->urg, tcp->ack,
191          tcp->psh, tcp->rst, tcp->syn, tcp->fin);
192   printf("window = %x\n", ntohs(tcp->window));
193   printf("check = %x [mine %x]\n", tcp->check, my_checksum);
194   printf("urgent = %x\n", tcp->urg_ptr);
195 
196   if (options) {
197     size_t i;
198 
199     printf("options: ");
200     for (i = 0; i < options_size; i++) {
201       printf("%x ", *(options + i));
202     }
203     printf("\n");
204   }
205 }
206 
207 /* print ipv4/tcp header */
dump_tcp(const struct tcphdr * tcp,const struct iphdr * ip,const uint8_t * payload,size_t payload_size,const uint8_t * options,size_t options_size)208 void dump_tcp(const struct tcphdr *tcp, const struct iphdr *ip, const uint8_t *payload,
209               size_t payload_size, const uint8_t *options, size_t options_size) {
210   uint32_t temp_checksum;
211 
212   temp_checksum = ipv4_pseudo_header_checksum(ip, sizeof(*tcp) + options_size + payload_size);
213   dump_tcp_generic(tcp, options, options_size, temp_checksum, payload, payload_size);
214 }
215 
216 /* print ipv6/tcp header */
dump_tcp6(const struct tcphdr * tcp,const struct ip6_hdr * ip6,const uint8_t * payload,size_t payload_size,const uint8_t * options,size_t options_size)217 void dump_tcp6(const struct tcphdr *tcp, const struct ip6_hdr *ip6, const uint8_t *payload,
218                size_t payload_size, const uint8_t *options, size_t options_size) {
219   uint32_t temp_checksum;
220 
221   temp_checksum =
222     ipv6_pseudo_header_checksum(ip6, sizeof(*tcp) + options_size + payload_size, IPPROTO_TCP);
223   dump_tcp_generic(tcp, options, options_size, temp_checksum, payload, payload_size);
224 }
225 
226 /* generic hex dump */
logcat_hexdump(const char * info,const uint8_t * data,size_t len)227 void logcat_hexdump(const char *info, const uint8_t *data, size_t len) {
228   char output[PACKETLEN * 3 + 2];
229   size_t i;
230 
231   output[0] = '\0';
232   for (i = 0; i < len && i < PACKETLEN; i++) {
233     snprintf(output + i * 3, 4, " %02x", data[i]);
234   }
235   output[len * 3 + 3] = '\0';
236 
237   logmsg(ANDROID_LOG_WARN, "info %s len %d data%s", info, len, output);
238 }
239 
dump_iovec(const struct iovec * iov,int iov_len)240 void dump_iovec(const struct iovec *iov, int iov_len) {
241   int i;
242   char *str;
243   for (i = 0; i < iov_len; i++) {
244     asprintf(&str, "iov[%d]: ", i);
245     logcat_hexdump(str, iov[i].iov_base, iov[i].iov_len);
246     free(str);
247   }
248 }
249 #endif  // CLAT_DEBUG
250