tcp_helper.c

00001 #include "tcp_helper.h"
00002 
00003 #include "lwip/priv/tcp_priv.h"
00004 #include "lwip/stats.h"
00005 #include "lwip/pbuf.h"
00006 #include "lwip/inet_chksum.h"
00007 #include "lwip/ip_addr.h"
00008 
00009 #if !LWIP_STATS || !TCP_STATS || !MEMP_STATS
00010 #error "This tests needs TCP- and MEMP-statistics enabled"
00011 #endif
00012 
00013 /** Remove all pcbs on the given list. */
00014 static void
00015 tcp_remove(struct tcp_pcb* pcb_list)
00016 {
00017   struct tcp_pcb *pcb = pcb_list;
00018   struct tcp_pcb *pcb2;
00019 
00020   while(pcb != NULL) {
00021     pcb2 = pcb;
00022     pcb = pcb->next;
00023     tcp_abort(pcb2);
00024   }
00025 }
00026 
00027 /** Remove all pcbs on listen-, active- and time-wait-list (bound- isn't exported). */
00028 void
00029 tcp_remove_all(void)
00030 {
00031   tcp_remove(tcp_listen_pcbs.pcbs);
00032   tcp_remove(tcp_active_pcbs);
00033   tcp_remove(tcp_tw_pcbs);
00034   fail_unless(MEMP_STATS_GET(used, MEMP_TCP_PCB) == 0);
00035   fail_unless(MEMP_STATS_GET(used, MEMP_TCP_PCB_LISTEN) == 0);
00036   fail_unless(MEMP_STATS_GET(used, MEMP_TCP_SEG) == 0);
00037   fail_unless(MEMP_STATS_GET(used, MEMP_PBUF_POOL) == 0);
00038 }
00039 
00040 /** Create a TCP segment usable for passing to tcp_input */
00041 static struct pbuf*
00042 tcp_create_segment_wnd(ip_addr_t* src_ip, ip_addr_t* dst_ip,
00043                    u16_t src_port, u16_t dst_port, void* data, size_t data_len,
00044                    u32_t seqno, u32_t ackno, u8_t headerflags, u16_t wnd)
00045 {
00046   struct pbuf *p, *q;
00047   struct ip_hdr* iphdr;
00048   struct tcp_hdr* tcphdr;
00049   u16_t pbuf_len = (u16_t)(sizeof(struct ip_hdr) + sizeof(struct tcp_hdr) + data_len);
00050   LWIP_ASSERT("data_len too big", data_len <= 0xFFFF);
00051 
00052   p = pbuf_alloc(PBUF_RAW, pbuf_len, PBUF_POOL);
00053   EXPECT_RETNULL(p != NULL);
00054   /* first pbuf must be big enough to hold the headers */
00055   EXPECT_RETNULL(p->len >= (sizeof(struct ip_hdr) + sizeof(struct tcp_hdr)));
00056   if (data_len > 0) {
00057     /* first pbuf must be big enough to hold at least 1 data byte, too */
00058     EXPECT_RETNULL(p->len > (sizeof(struct ip_hdr) + sizeof(struct tcp_hdr)));
00059   }
00060 
00061   for(q = p; q != NULL; q = q->next) {
00062     memset(q->payload, 0, q->len);
00063   }
00064 
00065   iphdr = (struct ip_hdr*)p->payload;
00066   /* fill IP header */
00067   iphdr->dest.addr = ip_2_ip4(dst_ip)->addr;
00068   iphdr->src.addr = ip_2_ip4(src_ip)->addr;
00069   IPH_VHL_SET(iphdr, 4, IP_HLEN / 4);
00070   IPH_TOS_SET(iphdr, 0);
00071   IPH_LEN_SET(iphdr, htons(p->tot_len));
00072   IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, IP_HLEN));
00073 
00074   /* let p point to TCP header */
00075   pbuf_header(p, -(s16_t)sizeof(struct ip_hdr));
00076 
00077   tcphdr = (struct tcp_hdr*)p->payload;
00078   tcphdr->src   = htons(src_port);
00079   tcphdr->dest  = htons(dst_port);
00080   tcphdr->seqno = htonl(seqno);
00081   tcphdr->ackno = htonl(ackno);
00082   TCPH_HDRLEN_SET(tcphdr, sizeof(struct tcp_hdr)/4);
00083   TCPH_FLAGS_SET(tcphdr, headerflags);
00084   tcphdr->wnd   = htons(wnd);
00085 
00086   if (data_len > 0) {
00087     /* let p point to TCP data */
00088     pbuf_header(p, -(s16_t)sizeof(struct tcp_hdr));
00089     /* copy data */
00090     pbuf_take(p, data, (u16_t)data_len);
00091     /* let p point to TCP header again */
00092     pbuf_header(p, sizeof(struct tcp_hdr));
00093   }
00094 
00095   /* calculate checksum */
00096 
00097   tcphdr->chksum = ip_chksum_pseudo(p,
00098           IP_PROTO_TCP, p->tot_len, src_ip, dst_ip);
00099 
00100   pbuf_header(p, sizeof(struct ip_hdr));
00101 
00102   return p;
00103 }
00104 
00105 /** Create a TCP segment usable for passing to tcp_input */
00106 struct pbuf*
00107 tcp_create_segment(ip_addr_t* src_ip, ip_addr_t* dst_ip,
00108                    u16_t src_port, u16_t dst_port, void* data, size_t data_len,
00109                    u32_t seqno, u32_t ackno, u8_t headerflags)
00110 {
00111   return tcp_create_segment_wnd(src_ip, dst_ip, src_port, dst_port, data,
00112     data_len, seqno, ackno, headerflags, TCP_WND);
00113 }
00114 
00115 /** Create a TCP segment usable for passing to tcp_input
00116  * - IP-addresses, ports, seqno and ackno are taken from pcb
00117  * - seqno and ackno can be altered with an offset
00118  */
00119 struct pbuf*
00120 tcp_create_rx_segment(struct tcp_pcb* pcb, void* data, size_t data_len, u32_t seqno_offset,
00121                       u32_t ackno_offset, u8_t headerflags)
00122 {
00123   return tcp_create_segment(&pcb->remote_ip, &pcb->local_ip, pcb->remote_port, pcb->local_port,
00124     data, data_len, pcb->rcv_nxt + seqno_offset, pcb->lastack + ackno_offset, headerflags);
00125 }
00126 
00127 /** Create a TCP segment usable for passing to tcp_input
00128  * - IP-addresses, ports, seqno and ackno are taken from pcb
00129  * - seqno and ackno can be altered with an offset
00130  * - TCP window can be adjusted
00131  */
00132 struct pbuf* tcp_create_rx_segment_wnd(struct tcp_pcb* pcb, void* data, size_t data_len,
00133                    u32_t seqno_offset, u32_t ackno_offset, u8_t headerflags, u16_t wnd)
00134 {
00135   return tcp_create_segment_wnd(&pcb->remote_ip, &pcb->local_ip, pcb->remote_port, pcb->local_port,
00136     data, data_len, pcb->rcv_nxt + seqno_offset, pcb->lastack + ackno_offset, headerflags, wnd);
00137 }
00138 
00139 /** Safely bring a tcp_pcb into the requested state */
00140 void
00141 tcp_set_state(struct tcp_pcb* pcb, enum tcp_state state, ip_addr_t* local_ip,
00142                    ip_addr_t* remote_ip, u16_t local_port, u16_t remote_port)
00143 {
00144   /* @todo: are these all states? */
00145   /* @todo: remove from previous list */
00146   pcb->state = state;
00147   if (state == ESTABLISHED) {
00148     TCP_REG(&tcp_active_pcbs, pcb);
00149     pcb->local_ip.addr = local_ip->addr;
00150     pcb->local_port = local_port;
00151     pcb->remote_ip.addr = remote_ip->addr;
00152     pcb->remote_port = remote_port;
00153   } else if(state == LISTEN) {
00154     TCP_REG(&tcp_listen_pcbs.pcbs, pcb);
00155     pcb->local_ip.addr = local_ip->addr;
00156     pcb->local_port = local_port;
00157   } else if(state == TIME_WAIT) {
00158     TCP_REG(&tcp_tw_pcbs, pcb);
00159     pcb->local_ip.addr = local_ip->addr;
00160     pcb->local_port = local_port;
00161     pcb->remote_ip.addr = remote_ip->addr;
00162     pcb->remote_port = remote_port;
00163   } else {
00164     fail();
00165   }
00166 }
00167 
00168 void
00169 test_tcp_counters_err(void* arg, err_t err)
00170 {
00171   struct test_tcp_counters* counters = (struct test_tcp_counters*)arg;
00172   EXPECT_RET(arg != NULL);
00173   counters->err_calls++;
00174   counters->last_err = err;
00175 }
00176 
00177 static void
00178 test_tcp_counters_check_rxdata(struct test_tcp_counters* counters, struct pbuf* p)
00179 {
00180   struct pbuf* q;
00181   u32_t i, received;
00182   if(counters->expected_data == NULL) {
00183     /* no data to compare */
00184     return;
00185   }
00186   EXPECT_RET(counters->recved_bytes + p->tot_len <= counters->expected_data_len);
00187   received = counters->recved_bytes;
00188   for(q = p; q != NULL; q = q->next) {
00189     char *data = (char*)q->payload;
00190     for(i = 0; i < q->len; i++) {
00191       EXPECT_RET(data[i] == counters->expected_data[received]);
00192       received++;
00193     }
00194   }
00195   EXPECT(received == counters->recved_bytes + p->tot_len);
00196 }
00197 
00198 err_t
00199 test_tcp_counters_recv(void* arg, struct tcp_pcb* pcb, struct pbuf* p, err_t err)
00200 {
00201   struct test_tcp_counters* counters = (struct test_tcp_counters*)arg;
00202   EXPECT_RETX(arg != NULL, ERR_OK);
00203   EXPECT_RETX(pcb != NULL, ERR_OK);
00204   EXPECT_RETX(err == ERR_OK, ERR_OK);
00205 
00206   if (p != NULL) {
00207     if (counters->close_calls == 0) {
00208       counters->recv_calls++;
00209       test_tcp_counters_check_rxdata(counters, p);
00210       counters->recved_bytes += p->tot_len;
00211     } else {
00212       counters->recv_calls_after_close++;
00213       counters->recved_bytes_after_close += p->tot_len;
00214     }
00215     pbuf_free(p);
00216   } else {
00217     counters->close_calls++;
00218   }
00219   EXPECT(counters->recv_calls_after_close == 0 && counters->recved_bytes_after_close == 0);
00220   return ERR_OK;
00221 }
00222 
00223 /** Allocate a pcb and set up the test_tcp_counters_* callbacks */
00224 struct tcp_pcb*
00225 test_tcp_new_counters_pcb(struct test_tcp_counters* counters)
00226 {
00227   struct tcp_pcb* pcb = tcp_new();
00228   if (pcb != NULL) {
00229     /* set up args and callbacks */
00230     tcp_arg(pcb, counters);
00231     tcp_recv(pcb, test_tcp_counters_recv);
00232     tcp_err(pcb, test_tcp_counters_err);
00233     pcb->snd_wnd = TCP_WND;
00234     pcb->snd_wnd_max = TCP_WND;
00235   }
00236   return pcb;
00237 }
00238 
00239 /** Calls tcp_input() after adjusting current_iphdr_dest */
00240 void test_tcp_input(struct pbuf *p, struct netif *inp)
00241 {
00242   struct ip_hdr *iphdr = (struct ip_hdr*)p->payload;
00243   /* these lines are a hack, don't use them as an example :-) */
00244   ip_addr_copy_from_ip4(*ip_current_dest_addr(), iphdr->dest);
00245   ip_addr_copy_from_ip4(*ip_current_src_addr(), iphdr->src);
00246   ip_current_netif() = inp;
00247   ip_data.current_ip4_header = iphdr;
00248 
00249   /* since adding IPv6, p->payload must point to tcp header, not ip header */
00250   pbuf_header(p, -(s16_t)sizeof(struct ip_hdr));
00251 
00252   tcp_input(p, inp);
00253 
00254   ip_addr_set_zero(ip_current_dest_addr());
00255   ip_addr_set_zero(ip_current_src_addr());
00256   ip_current_netif() = NULL;
00257   ip_data.current_ip4_header = NULL;
00258 }
00259 
00260 static err_t test_tcp_netif_output(struct netif *netif, struct pbuf *p,
00261        const ip4_addr_t *ipaddr)
00262 {
00263   struct test_tcp_txcounters *txcounters = (struct test_tcp_txcounters*)netif->state;
00264   LWIP_UNUSED_ARG(ipaddr);
00265   if (txcounters != NULL)
00266   {
00267     txcounters->num_tx_calls++;
00268     txcounters->num_tx_bytes += p->tot_len;
00269     if (txcounters->copy_tx_packets) {
00270       struct pbuf *p_copy = pbuf_alloc(PBUF_LINK, p->tot_len, PBUF_RAM);
00271       err_t err;
00272       EXPECT(p_copy != NULL);
00273       err = pbuf_copy(p_copy, p);
00274       EXPECT(err == ERR_OK);
00275       if (txcounters->tx_packets == NULL) {
00276         txcounters->tx_packets = p_copy;
00277       } else {
00278         pbuf_cat(txcounters->tx_packets, p_copy);
00279       }
00280     }
00281   }
00282   return ERR_OK;
00283 }
00284 
00285 void test_tcp_init_netif(struct netif *netif, struct test_tcp_txcounters *txcounters,
00286                          ip_addr_t *ip_addr, ip_addr_t *netmask)
00287 {
00288   struct netif *n;
00289   memset(netif, 0, sizeof(struct netif));
00290   if (txcounters != NULL) {
00291     memset(txcounters, 0, sizeof(struct test_tcp_txcounters));
00292     netif->state = txcounters;
00293   }
00294   netif->output = test_tcp_netif_output;
00295   netif->flags |= NETIF_FLAG_UP | NETIF_FLAG_LINK_UP;
00296   ip4_addr_copy(netif->netmask, *ip_2_ip4(netmask));
00297   ip4_addr_copy(netif->ip_addr, *ip_2_ip4(ip_addr));
00298   for (n = netif_list; n != NULL; n = n->next) {
00299     if (n == netif) {
00300       return;
00301     }
00302   }
00303   netif->next = NULL;
00304   netif_list = netif;
00305 }