1 #include "tcp_helper.h"
2 
3 #include "lwip/tcp_impl.h"
4 #include "lwip/stats.h"
5 #include "lwip/pbuf.h"
6 #include "lwip/inet_chksum.h"
7 
8 #if !LWIP_STATS || !TCP_STATS || !MEMP_STATS
9 #error "This tests needs TCP- and MEMP-statistics enabled"
10 #endif
11 
12 /** Remove all pcbs on the given list. */
13 static void
14 tcp_remove(struct tcp_pcb* pcb_list)
15 {
16   struct tcp_pcb *pcb = pcb_list;
17   struct tcp_pcb *pcb2;
18 
19   while(pcb != NULL) {
20     pcb2 = pcb;
21     pcb = pcb->next;
22     tcp_abort(pcb2);
23   }
24 }
25 
26 /** Remove all pcbs on listen-, active- and time-wait-list (bound- isn't exported). */
27 void
28 tcp_remove_all(void)
29 {
30   tcp_remove(tcp_listen_pcbs.pcbs);
31   tcp_remove(tcp_active_pcbs);
32   tcp_remove(tcp_tw_pcbs);
33   fail_unless(lwip_stats.memp[MEMP_TCP_PCB].used == 0);
34   fail_unless(lwip_stats.memp[MEMP_TCP_PCB_LISTEN].used == 0);
35   fail_unless(lwip_stats.memp[MEMP_TCP_SEG].used == 0);
36   fail_unless(lwip_stats.memp[MEMP_PBUF_POOL].used == 0);
37 }
38 
39 /** Create a TCP segment usable for passing to tcp_input */
40 static struct pbuf*
41 tcp_create_segment_wnd(ip_addr_t* src_ip, ip_addr_t* dst_ip,
42                    u16_t src_port, u16_t dst_port, void* data, size_t data_len,
43                    u32_t seqno, u32_t ackno, u8_t headerflags, u16_t wnd)
44 {
45   struct pbuf *p, *q;
46   struct ip_hdr* iphdr;
47   struct tcp_hdr* tcphdr;
48   u16_t pbuf_len = (u16_t)(sizeof(struct ip_hdr) + sizeof(struct tcp_hdr) + data_len);
49 
50   p = pbuf_alloc(PBUF_RAW, pbuf_len, PBUF_POOL);
51   EXPECT_RETNULL(p != NULL);
52   /* first pbuf must be big enough to hold the headers */
53   EXPECT_RETNULL(p->len >= (sizeof(struct ip_hdr) + sizeof(struct tcp_hdr)));
54   if (data_len > 0) {
55     /* first pbuf must be big enough to hold at least 1 data byte, too */
56     EXPECT_RETNULL(p->len > (sizeof(struct ip_hdr) + sizeof(struct tcp_hdr)));
57   }
58 
59   for(q = p; q != NULL; q = q->next) {
60     memset(q->payload, 0, q->len);
61   }
62 
63   iphdr = p->payload;
64   /* fill IP header */
65   iphdr->dest.addr = dst_ip->addr;
66   iphdr->src.addr = src_ip->addr;
67   IPH_VHL_SET(iphdr, 4, IP_HLEN / 4);
68   IPH_TOS_SET(iphdr, 0);
69   IPH_LEN_SET(iphdr, htons(p->tot_len));
70   IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, IP_HLEN));
71 
72   /* let p point to TCP header */
73   pbuf_header(p, -(s16_t)sizeof(struct ip_hdr));
74 
75   tcphdr = p->payload;
76   tcphdr->src   = htons(src_port);
77   tcphdr->dest  = htons(dst_port);
78   tcphdr->seqno = htonl(seqno);
79   tcphdr->ackno = htonl(ackno);
80   TCPH_HDRLEN_SET(tcphdr, sizeof(struct tcp_hdr)/4);
81   TCPH_FLAGS_SET(tcphdr, headerflags);
82   tcphdr->wnd   = htons(wnd);
83 
84   if (data_len > 0) {
85     /* let p point to TCP data */
86     pbuf_header(p, -(s16_t)sizeof(struct tcp_hdr));
87     /* copy data */
88     pbuf_take(p, data, data_len);
89     /* let p point to TCP header again */
90     pbuf_header(p, sizeof(struct tcp_hdr));
91   }
92 
93   /* calculate checksum */
94 
95   tcphdr->chksum = inet_chksum_pseudo(p, src_ip, dst_ip,
96           IP_PROTO_TCP, p->tot_len);
97 
98   pbuf_header(p, sizeof(struct ip_hdr));
99 
100   return p;
101 }
102 
103 /** Create a TCP segment usable for passing to tcp_input */
104 struct pbuf*
105 tcp_create_segment(ip_addr_t* src_ip, ip_addr_t* dst_ip,
106                    u16_t src_port, u16_t dst_port, void* data, size_t data_len,
107                    u32_t seqno, u32_t ackno, u8_t headerflags)
108 {
109   return tcp_create_segment_wnd(src_ip, dst_ip, src_port, dst_port, data,
110     data_len, seqno, ackno, headerflags, TCP_WND);
111 }
112 
113 /** Create a TCP segment usable for passing to tcp_input
114  * - IP-addresses, ports, seqno and ackno are taken from pcb
115  * - seqno and ackno can be altered with an offset
116  */
117 struct pbuf*
118 tcp_create_rx_segment(struct tcp_pcb* pcb, void* data, size_t data_len, u32_t seqno_offset,
119                       u32_t ackno_offset, u8_t headerflags)
120 {
121   return tcp_create_segment(&pcb->remote_ip, &pcb->local_ip, pcb->remote_port, pcb->local_port,
122     data, data_len, pcb->rcv_nxt + seqno_offset, pcb->lastack + ackno_offset, headerflags);
123 }
124 
125 /** Create a TCP segment usable for passing to tcp_input
126  * - IP-addresses, ports, seqno and ackno are taken from pcb
127  * - seqno and ackno can be altered with an offset
128  * - TCP window can be adjusted
129  */
130 struct pbuf* tcp_create_rx_segment_wnd(struct tcp_pcb* pcb, void* data, size_t data_len,
131                    u32_t seqno_offset, u32_t ackno_offset, u8_t headerflags, u16_t wnd)
132 {
133   return tcp_create_segment_wnd(&pcb->remote_ip, &pcb->local_ip, pcb->remote_port, pcb->local_port,
134     data, data_len, pcb->rcv_nxt + seqno_offset, pcb->lastack + ackno_offset, headerflags, wnd);
135 }
136 
137 /** Safely bring a tcp_pcb into the requested state */
138 void
139 tcp_set_state(struct tcp_pcb* pcb, enum tcp_state state, ip_addr_t* local_ip,
140                    ip_addr_t* remote_ip, u16_t local_port, u16_t remote_port)
141 {
142   /* @todo: are these all states? */
143   /* @todo: remove from previous list */
144   pcb->state = state;
145   if (state == ESTABLISHED) {
146     TCP_REG(&tcp_active_pcbs, pcb);
147     pcb->local_ip.addr = local_ip->addr;
148     pcb->local_port = local_port;
149     pcb->remote_ip.addr = remote_ip->addr;
150     pcb->remote_port = remote_port;
151   } else if(state == LISTEN) {
152     TCP_REG(&tcp_listen_pcbs.pcbs, pcb);
153     pcb->local_ip.addr = local_ip->addr;
154     pcb->local_port = local_port;
155   } else if(state == TIME_WAIT) {
156     TCP_REG(&tcp_tw_pcbs, pcb);
157     pcb->local_ip.addr = local_ip->addr;
158     pcb->local_port = local_port;
159     pcb->remote_ip.addr = remote_ip->addr;
160     pcb->remote_port = remote_port;
161   } else {
162     fail();
163   }
164 }
165 
166 void
167 test_tcp_counters_err(void* arg, err_t err)
168 {
169   struct test_tcp_counters* counters = arg;
170   EXPECT_RET(arg != NULL);
171   counters->err_calls++;
172   counters->last_err = err;
173 }
174 
175 static void
176 test_tcp_counters_check_rxdata(struct test_tcp_counters* counters, struct pbuf* p)
177 {
178   struct pbuf* q;
179   u32_t i, received;
180   if(counters->expected_data == NULL) {
181     /* no data to compare */
182     return;
183   }
184   EXPECT_RET(counters->recved_bytes + p->tot_len <= counters->expected_data_len);
185   received = counters->recved_bytes;
186   for(q = p; q != NULL; q = q->next) {
187     char *data = q->payload;
188     for(i = 0; i < q->len; i++) {
189       EXPECT_RET(data[i] == counters->expected_data[received]);
190       received++;
191     }
192   }
193   EXPECT(received == counters->recved_bytes + p->tot_len);
194 }
195 
196 err_t
197 test_tcp_counters_recv(void* arg, struct tcp_pcb* pcb, struct pbuf* p, err_t err)
198 {
199   struct test_tcp_counters* counters = arg;
200   EXPECT_RETX(arg != NULL, ERR_OK);
201   EXPECT_RETX(pcb != NULL, ERR_OK);
202   EXPECT_RETX(err == ERR_OK, ERR_OK);
203 
204   if (p != NULL) {
205     if (counters->close_calls == 0) {
206       counters->recv_calls++;
207       test_tcp_counters_check_rxdata(counters, p);
208       counters->recved_bytes += p->tot_len;
209     } else {
210       counters->recv_calls_after_close++;
211       counters->recved_bytes_after_close += p->tot_len;
212     }
213     pbuf_free(p);
214   } else {
215     counters->close_calls++;
216   }
217   EXPECT(counters->recv_calls_after_close == 0 && counters->recved_bytes_after_close == 0);
218   return ERR_OK;
219 }
220 
221 /** Allocate a pcb and set up the test_tcp_counters_* callbacks */
222 struct tcp_pcb*
223 test_tcp_new_counters_pcb(struct test_tcp_counters* counters)
224 {
225   struct tcp_pcb* pcb = tcp_new();
226   if (pcb != NULL) {
227     /* set up args and callbacks */
228     tcp_arg(pcb, counters);
229     tcp_recv(pcb, test_tcp_counters_recv);
230     tcp_err(pcb, test_tcp_counters_err);
231     pcb->snd_wnd = TCP_WND;
232     pcb->snd_wnd_max = TCP_WND;
233   }
234   return pcb;
235 }
236 
237 /** Calls tcp_input() after adjusting current_iphdr_dest */
238 void test_tcp_input(struct pbuf *p, struct netif *inp)
239 {
240   struct ip_hdr *iphdr = (struct ip_hdr*)p->payload;
241   ip_addr_copy(current_iphdr_dest, iphdr->dest);
242   ip_addr_copy(current_iphdr_src, iphdr->src);
243   current_netif = inp;
244   current_header = iphdr;
245 
246   tcp_input(p, inp);
247 
248   current_iphdr_dest.addr = 0;
249   current_iphdr_src.addr = 0;
250   current_netif = NULL;
251   current_header = NULL;
252 }
253 
254 static err_t test_tcp_netif_output(struct netif *netif, struct pbuf *p,
255        ip_addr_t *ipaddr)
256 {
257   struct test_tcp_txcounters *txcounters = (struct test_tcp_txcounters*)netif->state;
258   LWIP_UNUSED_ARG(ipaddr);
259   txcounters->num_tx_calls++;
260   txcounters->num_tx_bytes += p->tot_len;
261   if (txcounters->copy_tx_packets) {
262     struct pbuf *p_copy = pbuf_alloc(PBUF_LINK, p->tot_len, PBUF_RAM);
263     err_t err;
264     EXPECT(p_copy != NULL);
265     err = pbuf_copy(p_copy, p);
266     EXPECT(err == ERR_OK);
267     if (txcounters->tx_packets == NULL) {
268       txcounters->tx_packets = p_copy;
269     } else {
270       pbuf_cat(txcounters->tx_packets, p_copy);
271     }
272   }
273   return ERR_OK;
274 }
275 
276 void test_tcp_init_netif(struct netif *netif, struct test_tcp_txcounters *txcounters,
277                          ip_addr_t *ip_addr, ip_addr_t *netmask)
278 {
279   struct netif *n;
280   memset(netif, 0, sizeof(struct netif));
281   memset(txcounters, 0, sizeof(struct test_tcp_txcounters));
282   netif->output = test_tcp_netif_output;
283   netif->state = txcounters;
284   netif->flags |= NETIF_FLAG_UP;
285   ip_addr_copy(netif->netmask, *netmask);
286   ip_addr_copy(netif->ip_addr, *ip_addr);
287   for (n = netif_list; n != NULL; n = n->next) {
288     if (n == netif) {
289       return;
290     }
291   }
292   netif->next = NULL;
293   netif_list = netif;
294 }
295