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-rw-r--r--extras/libmemif/examples/icmp_responder/icmp_proto.c105
1 files changed, 99 insertions, 6 deletions
diff --git a/extras/libmemif/examples/icmp_responder/icmp_proto.c b/extras/libmemif/examples/icmp_responder/icmp_proto.c
index a923f209126..b27abb6a231 100644
--- a/extras/libmemif/examples/icmp_responder/icmp_proto.c
+++ b/extras/libmemif/examples/icmp_responder/icmp_proto.c
@@ -137,8 +137,9 @@ resolve_eth_arp (struct ether_arp *eth_arp, void *eth_arp_resp,
memcpy (resp->arp_sha,
(((struct ether_header *) (eth_arp_resp -
- sizeof (struct ether_header)))->
- ether_shost), 6);
+ sizeof (struct
+ ether_header)))->ether_shost),
+ 6);
memcpy (resp->arp_spa, ip_addr, 4);
@@ -172,7 +173,7 @@ resolve_ip (struct iphdr *ip, void *ip_resp, uint8_t ip_addr[4])
resp->version = 4;
resp->tos = 0;
/*len updated later */
- resp->tot_len = 0x5400;
+ resp->tot_len = 0x0000;
resp->id = 0;
resp->frag_off = 0;
resp->ttl = 0x40;
@@ -183,7 +184,7 @@ resolve_ip (struct iphdr *ip, void *ip_resp, uint8_t ip_addr[4])
((uint8_t *) & resp->saddr)[3] = ip_addr[3];
resp->daddr = ip->saddr;
- resp->check = cksum (resp, sizeof (struct iphdr));
+ /* resp->check = cksum (resp, sizeof (struct iphdr)); */
return sizeof (struct iphdr);
}
@@ -192,7 +193,7 @@ static ssize_t
resolve_icmp (struct icmphdr *icmp, void *icmp_resp)
{
struct icmphdr *resp = (struct icmphdr *) icmp_resp;
- resp->type = ICMP_ECHOREPLY;
+ resp->type = 0x00;
resp->code = 0;
resp->un.echo.id = icmp->un.echo.id;
resp->un.echo.sequence = icmp->un.echo.sequence;
@@ -208,10 +209,13 @@ resolve_packet (void *in_pck, ssize_t in_size,
{
struct ether_header *eh;
struct ether_arp *eah;
- struct iphdr *ip;
+ struct iphdr *ip, *ip_out;
struct icmphdr *icmp;
*out_size = 0;
+ if ((in_pck == NULL) || (out_pck == NULL))
+ return -1;
+
eh = (struct ether_header *) in_pck;
*out_size = resolve_eth (eh, out_pck);
@@ -227,6 +231,7 @@ resolve_packet (void *in_pck, ssize_t in_size,
print_packet (in_pck + *out_size);
#endif
ip = (struct iphdr *) (in_pck + *out_size);
+ ip_out = (struct iphdr *) (out_pck + *out_size);
*out_size += resolve_ip (ip, out_pck + *out_size, ip_addr);
if (ip->protocol == 1)
{
@@ -240,7 +245,95 @@ resolve_packet (void *in_pck, ssize_t in_size,
memcpy (out_pck + *out_size, in_pck + *out_size,
in_size - *out_size);
*out_size = in_size;
+ ip_out->tot_len =
+ __bswap_16 (*out_size - sizeof (struct ether_header));
+ ip_out->check = cksum (ip_out, sizeof (struct iphdr));
}
}
return 0;
}
+
+static ssize_t
+generate_eth (struct ether_header *eh, uint8_t hw_daddr[6])
+{
+ uint8_t hw_addr[6];
+ int i;
+ for (i = 0; i < 6; i++)
+ {
+ hw_addr[i] = 'a';
+ }
+ memcpy (eh->ether_shost, hw_addr, 6);
+ memcpy (eh->ether_dhost, hw_daddr, 6);
+
+ eh->ether_type = 0x0008;
+
+ return sizeof (struct ether_header);
+}
+
+static ssize_t
+generate_ip (struct iphdr *ip, uint8_t saddr[4], uint8_t daddr[4])
+{
+ ip->ihl = 5;
+ ip->version = 4;
+ ip->tos = 0;
+ /*len updated later */
+ ip->tot_len = 0x5400;
+ ip->id = 0;
+ ip->frag_off = 0;
+ ip->ttl = 0x40;
+ ip->protocol = 1;
+ /* saddr */
+ ((uint8_t *) & ip->saddr)[0] = saddr[0];
+ ((uint8_t *) & ip->saddr)[1] = saddr[1];
+ ((uint8_t *) & ip->saddr)[2] = saddr[2];
+ ((uint8_t *) & ip->saddr)[3] = saddr[3];
+ /* daddr */
+ ((uint8_t *) & ip->daddr)[0] = daddr[0];
+ ((uint8_t *) & ip->daddr)[1] = daddr[1];
+ ((uint8_t *) & ip->daddr)[2] = daddr[2];
+ ((uint8_t *) & ip->daddr)[3] = daddr[3];
+
+ ip->check = cksum (ip, sizeof (struct iphdr));
+
+ return sizeof (struct iphdr);
+}
+
+static ssize_t
+generate_icmp (struct icmphdr *icmp, uint32_t seq)
+{
+ icmp->type = ICMP_ECHO;
+ icmp->code = 0;
+ icmp->un.echo.id = 0;
+ icmp->un.echo.sequence = seq;
+
+ return sizeof (struct icmphdr);
+}
+
+int
+generate_packet (void *pck, uint32_t * size, uint8_t saddr[4],
+ uint8_t daddr[4], uint8_t hw_daddr[6], uint32_t seq)
+{
+ struct ether_header *eh;
+ struct iphdr *ip;
+ struct icmphdr *icmp;
+
+ *size = 0;
+
+ eh = (struct ether_header *) pck;
+ *size += generate_eth (eh, hw_daddr);
+
+ ip = (struct iphdr *) (pck + *size);
+ *size += generate_ip (ip, saddr, daddr);
+
+ icmp = (struct icmphdr *) (pck + *size);
+ *size += generate_icmp (icmp, seq);
+
+ ((struct icmphdr *) (pck + *size - sizeof (struct icmphdr)))->checksum =
+ cksum (pck + *size - sizeof (struct icmphdr), sizeof (struct icmphdr));
+
+ ip->tot_len = __bswap_16 (*size - sizeof (struct ether_header));
+ ip->check = 0;
+ ip->check = cksum (ip, sizeof (struct iphdr));
+
+ return 0;
+}