diff options
author | 2021-01-04 11:28:33 +0100 | |
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committer | 2022-03-28 22:34:33 +0000 | |
commit | e74c04fc9fb2600470fe79a69d3ec6b0db95faec (patch) | |
tree | cc85fb480afcbe74184a56162d3d06af67cc4eb5 /extras/libmemif/examples/common/icmp_proto.c | |
parent | 7d6f7d0d67face9889e43bdb5f71f352294b918a (diff) |
libmemif: refactor examples
- icmp_responder: responds to ICMPv4 and ARP requests
- loopback: connects two interfaces and sends a
verification packet from master memif to slave memif
where it is looped back
- loopback (reverse path): reverses direction of packet
in loopback application (slave memif to master memif)
Type: refactor
Signed-off-by: Jakub Grajciar <jgrajcia@cisco.com>
Change-Id: Ie90aaa3367269408efb6c5d538ad5aa827432238
Signed-off-by: Dave Wallace <dwallacelf@gmail.com>
Diffstat (limited to 'extras/libmemif/examples/common/icmp_proto.c')
-rw-r--r-- | extras/libmemif/examples/common/icmp_proto.c | 520 |
1 files changed, 520 insertions, 0 deletions
diff --git a/extras/libmemif/examples/common/icmp_proto.c b/extras/libmemif/examples/common/icmp_proto.c new file mode 100644 index 00000000000..fafc8e425b9 --- /dev/null +++ b/extras/libmemif/examples/common/icmp_proto.c @@ -0,0 +1,520 @@ +/* + *------------------------------------------------------------------ + * Copyright (c) 2017 Cisco and/or its affiliates. + * 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. + *------------------------------------------------------------------ + */ + +#include <stdint.h> +#include <net/if.h> +#include <sys/types.h> +#include <fcntl.h> +#include <sys/ioctl.h> +#include <sys/socket.h> +#include <sys/un.h> +#include <sys/uio.h> +#include <sys/mman.h> +#include <sys/prctl.h> +#include <inttypes.h> +#include <string.h> +#include <stdio.h> +#include <netdb.h> +#include <linux/ip.h> +#include <linux/icmp.h> +#include <arpa/inet.h> +#include <stdlib.h> +#include <netinet/if_ether.h> +#include <net/if_arp.h> +#include <asm/byteorder.h> +#include <byteswap.h> +#include <assert.h> + +#include <icmp_proto.h> + +static uint16_t +cksum (void *addr, ssize_t len) +{ + char *data = (char *) addr; + + uint32_t acc = 0xffff; + + ssize_t i; + for (i = 0; (i + 1) < len; i += 2) + { + uint16_t word; + memcpy (&word, data + i, 2); + acc += ntohs (word); + if (acc > 0xffff) + acc -= 0xffff; + } + + if (len & 1) + { + uint16_t word = 0; + memcpy (&word, data + len - 1, 1); + acc += ntohs (word); + if (acc > 0xffff) + acc -= 0xffff; + } + return htons (~acc); +} + +int +print_packet (void *pck) +{ + if (pck == NULL) + { + printf ("ICMP_PROTO: no data\n"); + return -1; + } + struct iphdr *ip; + struct icmphdr *icmp; + ip = (struct iphdr *) pck; + icmp = (struct icmphdr *) (pck + sizeof (struct iphdr)); + printf ("received packet:\n"); + printf ("\tiphdr:\n"); + printf ("\t\tihl: %u\n\t\tversion: %u\n\t\tlen: %u\n\t\tid: %u\n", ip->ihl, + ip->version, __bswap_16 (ip->tot_len), ip->id); + printf ("\t\tprotocol: %u\n", ip->protocol); + + printf ("\t\tsaddr: "); + int i; + for (i = 0; i < 4; i++) + { + printf ("%u.", ((uint8_t *) &ip->saddr)[i]); + } + printf ("\n"); + + printf ("\t\tdaddr: "); + for (i = 0; i < 4; i++) + { + printf ("%u.", ((uint8_t *) &ip->daddr)[i]); + } + printf ("\n"); + printf ("\ticmphdr:\n"); + printf ("\t\ttype: %s\n", + (icmp->type == ICMP_ECHO) ? "ICMP_ECHO" : "ICMP_ECHOREPLY"); + + return 0; +} + +static ssize_t +resolve_arp (void *arp) +{ + struct arphdr *resp = (struct arphdr *) arp; + + resp->ar_hrd = __bswap_16 (ARPHRD_ETHER); + + resp->ar_pro = __bswap_16 (0x0800); + + resp->ar_hln = 6; + resp->ar_pln = 4; + + resp->ar_op = __bswap_16 (ARPOP_REPLY); + + return sizeof (struct arphdr); +} + +static ssize_t +resolve_eth_arp (struct ether_arp *eth_arp, void *eth_arp_resp, + uint8_t ip_addr[4]) +{ + struct ether_arp *resp = (struct ether_arp *) eth_arp_resp; + + resolve_arp (&resp->ea_hdr); + + memcpy (resp->arp_tha, eth_arp->arp_sha, 6); + memcpy (resp->arp_tpa, eth_arp->arp_spa, 4); + + memcpy ( + resp->arp_sha, + (((struct ether_header *) (eth_arp_resp - sizeof (struct ether_header))) + ->ether_shost), + 6); + + memcpy (resp->arp_spa, ip_addr, 4); + + return sizeof (struct ether_arp); +} + +static ssize_t +resolve_eth (struct ether_header *eth, void *eth_resp, uint8_t hw_addr[6]) +{ + struct ether_header *resp = (struct ether_header *) eth_resp; + memcpy (resp->ether_dhost, eth->ether_shost, 6); + + memcpy (resp->ether_shost, hw_addr, 6); + + resp->ether_type = eth->ether_type; + + return sizeof (struct ether_header); +} + +static ssize_t +resolve_ip (struct iphdr *ip, void *ip_resp, uint8_t ip_addr[4]) +{ + struct iphdr *resp = (struct iphdr *) ip_resp; + resp->ihl = 5; + resp->version = 4; + resp->tos = 0; + /*len updated later */ + resp->tot_len = 0x0000; + resp->id = 0; + resp->frag_off = 0; + resp->ttl = 0x40; + resp->protocol = 1; + ((uint8_t *) &resp->saddr)[0] = ip_addr[0]; + ((uint8_t *) &resp->saddr)[1] = ip_addr[1]; + ((uint8_t *) &resp->saddr)[2] = ip_addr[2]; + ((uint8_t *) &resp->saddr)[3] = ip_addr[3]; + resp->daddr = ip->saddr; + + /* resp->check = cksum (resp, sizeof (struct iphdr)); */ + + return sizeof (struct iphdr); +} + +static ssize_t +resolve_icmp (struct icmphdr *icmp, void *icmp_resp) +{ + struct icmphdr *resp = (struct icmphdr *) icmp_resp; + resp->type = 0x00; + resp->code = 0; + resp->un.echo.id = icmp->un.echo.id; + resp->un.echo.sequence = icmp->un.echo.sequence; + + /*resp->checksum = cksum (resp, sizeof (struct icmphdr)); */ + + return sizeof (struct icmphdr); +} + +int +resolve_packet (void *in_pck, ssize_t in_size, void *out_pck, + uint32_t *out_size, uint8_t ip_addr[4], uint8_t hw_addr[6]) +{ + struct ether_header *eh; + struct ether_arp *eah; + 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, hw_addr); + + if (eh->ether_type == 0x0608) + { + eah = (struct ether_arp *) (in_pck + *out_size); + *out_size += resolve_eth_arp (eah, out_pck + *out_size, ip_addr); + } + else if (eh->ether_type == 0x0008) + { +#ifdef ICMP_DBG + 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) + { + icmp = (struct icmphdr *) (in_pck + *out_size); + *out_size += resolve_icmp (icmp, out_pck + *out_size); + ((struct icmphdr *) (out_pck + *out_size - sizeof (struct icmphdr))) + ->checksum = cksum (out_pck + *out_size - sizeof (struct icmphdr), + sizeof (struct icmphdr)); + /* payload */ + 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; +} + +int +generate_packet2 (void *pck, uint32_t *size, uint8_t saddr[4], + uint8_t daddr[4], uint8_t hw_daddr[6], uint32_t seq, + icmpr_flow_mode_t mode) +{ + struct ether_header *eh; + struct iphdr *ip; + struct icmphdr *icmp; + + *size = 0; + + if (mode == ICMPR_FLOW_MODE_ETH) + { + 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; +} + +#define GET_HEADER(out, hdr, src, off) \ + do \ + { \ + out = (hdr *) (src + off); \ + off += sizeof (hdr); \ + } \ + while (0) + +int +resolve_packet_zero_copy (void *pck, uint32_t *size, uint8_t ip_addr[4], + uint8_t hw_addr[6]) +{ + struct ether_header *eh; + struct ether_arp *eah; + struct iphdr *ip; + struct icmphdr *icmp; + uint32_t offset = 0; + + if (pck == NULL) + return 0; + + GET_HEADER (eh, struct ether_header, pck, offset); + + memcpy (eh->ether_dhost, eh->ether_shost, 6); + memcpy (eh->ether_shost, hw_addr, 6); + + if (eh->ether_type == 0x0608) + { + GET_HEADER (eah, struct ether_arp, pck, offset); + struct arphdr *arp = &eah->ea_hdr; + + arp->ar_hrd = __bswap_16 (ARPHRD_ETHER); + arp->ar_pro = __bswap_16 (0x0800); + + arp->ar_hln = 6; + arp->ar_pln = 4; + + arp->ar_op = __bswap_16 (ARPOP_REPLY); + + memcpy (eah->arp_tha, eah->arp_sha, 6); + memcpy (eah->arp_tpa, eah->arp_spa, 4); + + memcpy (eah->arp_sha, eh->ether_shost, 6); + memcpy (eah->arp_spa, ip_addr, 4); + } + + else if (eh->ether_type == 0x0008) + { + GET_HEADER (ip, struct iphdr, pck, offset); + + if (ip->protocol == 1) + { + ip->ihl = 5; + ip->version = 4; + ip->tos = 0; + ip->tot_len = 0x0000; + ip->id = 0; + ip->frag_off = 0; + ip->ttl = 0x40; + ip->protocol = 1; + ip->check = 0x0000; + ip->daddr = ip->saddr; + ((uint8_t *) &ip->saddr)[0] = ip_addr[0]; + ((uint8_t *) &ip->saddr)[1] = ip_addr[1]; + ((uint8_t *) &ip->saddr)[2] = ip_addr[2]; + ((uint8_t *) &ip->saddr)[3] = ip_addr[3]; + + GET_HEADER (icmp, struct icmphdr, pck, offset); + + icmp->type = 0x00; + icmp->code = 0; + icmp->checksum = cksum (icmp, sizeof (struct icmphdr)); + + /* rest is payload */ + offset = *size; + + ip->tot_len = __bswap_16 (offset - sizeof (struct ether_header)); + ip->check = cksum (ip, sizeof (struct iphdr)); + } + } + + assert (offset == *size && "unsupported protocol"); + return 0; +} + +int +resolve_packet_zero_copy_add_encap (void **pck_, uint32_t *size, + uint8_t ip_addr[4]) +{ + struct ether_header *eh; + struct iphdr *ip; + struct icmphdr *icmp; + int32_t offset = 0; + uint16_t encap_size = sizeof (struct ether_header); + void *pck = *pck_; + + if (pck == NULL) + return 0; + + *pck_ -= encap_size; + offset -= encap_size; + + GET_HEADER (eh, struct ether_header, pck, offset); + + uint8_t hw_daddr[6]; + memset (hw_daddr, 0, sizeof (uint8_t) * 6); + + generate_eth (eh, hw_daddr); + + if (eh->ether_type == 0x0008) + { + GET_HEADER (ip, struct iphdr, pck, offset); + + if (ip->protocol == 1) + { + ip->ihl = 5; + ip->version = 4; + ip->tos = 0; + ip->tot_len = 0x0000; + ip->id = 0; + ip->frag_off = 0; + ip->ttl = 0x40; + ip->protocol = 1; + ip->check = 0x0000; + ip->daddr = ip->saddr; + ((uint8_t *) &ip->saddr)[0] = ip_addr[0]; + ((uint8_t *) &ip->saddr)[1] = ip_addr[1]; + ((uint8_t *) &ip->saddr)[2] = ip_addr[2]; + ((uint8_t *) &ip->saddr)[3] = ip_addr[3]; + + GET_HEADER (icmp, struct icmphdr, pck, offset); + + icmp->type = 0x00; + icmp->code = 0; + icmp->checksum = cksum (icmp, sizeof (struct icmphdr)); + + /* rest is payload */ + offset = *size; + + ip->tot_len = __bswap_16 (offset - sizeof (struct ether_header)); + ip->check = cksum (ip, sizeof (struct iphdr)); + } + } + + offset += encap_size; + + assert (offset != *size && + "new packet length must be increased by encap size"); + + /* overwrite packet size */ + *size = offset; + + return 0; +} |