diff options
Diffstat (limited to 'src/user/app')
| -rw-r--r-- | src/user/app/ethdump/ipv4.c | 36 |
1 files changed, 22 insertions, 14 deletions
diff --git a/src/user/app/ethdump/ipv4.c b/src/user/app/ethdump/ipv4.c index fda0c0c..3243d3c 100644 --- a/src/user/app/ethdump/ipv4.c +++ b/src/user/app/ethdump/ipv4.c @@ -183,25 +183,33 @@ void ipv4_parse(const uint8_t *buf, size_t len, struct ethernet ether) { } } +static uint16_t next_id = 0; void ipv4_send(const void *payload, size_t len, struct ipv4 ip) { - size_t hdrlen = 20; + const size_t mtu = 1500; + const size_t hdrlen = 20; ip.e.type = ET_IPv4; if (!ip.src) ip.src = state.ip; if (!ip.e.dst && ip.dst == 0xFFFFFFFF) ip.e.dst = &MAC_BROADCAST; - // TODO output fragmentation - - uint8_t *pkt = ether_start(hdrlen + len, ip.e); - pkt[Version] = 0x40; - pkt[HdrLen] |= hdrlen / 4; - nput16(pkt + TotalLen, len + hdrlen); - pkt[TTL] = 0xFF; - pkt[Proto] = ip.proto; - nput32(pkt + SrcIP, ip.src); - nput32(pkt + DstIP, ip.dst); - nput16(pkt + Checksum, ip_checksum(pkt, hdrlen)); - memcpy(pkt + hdrlen, payload, len); - ether_finish(pkt); + uint16_t id = next_id++; + for (size_t off = 0, fraglen = mtu - hdrlen; off < len; off += fraglen) { + if (fraglen > len - off) + fraglen = len - off; + bool last = off + fraglen >= len; + uint8_t *pkt = ether_start(hdrlen + fraglen, ip.e); + pkt[Version] = 0x40; + pkt[HdrLen] |= hdrlen / 4; + nput16(pkt + TotalLen, hdrlen + fraglen); + nput16(pkt + Id, id); + nput16(pkt + FragInfo, (off >> 3) | (last ? 0 : MoreFrags)); + pkt[TTL] = 0xFF; + pkt[Proto] = ip.proto; + nput32(pkt + SrcIP, ip.src); + nput32(pkt + DstIP, ip.dst); + nput16(pkt + Checksum, ip_checksum(pkt, hdrlen)); + memcpy(pkt + hdrlen, payload + off, fraglen); + ether_finish(pkt); + } } |