Thanks. I'm really not versed enough in the DHCP RFC to make much sense out of this. Waldemar, can you please review? Thanks.
-- Nadav Har'El [email protected] On Thu, Mar 23, 2017 at 12:41 AM, Justin Cinkelj <[email protected]> wrote: > The patch works OK for me, tested agains dnsmasq. > > One possible improvements. From RFC 2131, page 30-31 > o DHCPREQUEST generated during SELECTING state: > Client inserts the address of the selected server in 'server > identifier', 'ciaddr' MUST be zero, 'requested IP address MUST be > filled in with the yiaddr value from the chosen DHCPOFFER. > > o DHCPREQUEST generated during RENEWING state: > 'server identifier' MUST NOT be filled in, 'requested IP address' > option MUST NOT be filled in, 'ciaddr' MUST be filled in with > client's IP address. > > I understand "'server identifier'/'requested IP address' MUST NOT be > filled in" > as instruction to not include those two DHCP OPTIONS into > RENEWING/REBINDING DHCPREQUEST. > So I tried to add additional change, as an attempt to be more RFC > compliant. > After that change, code still works - well, at least against dnsmasq. > > diff --git a/core/dhcp.cc b/core/dhcp.cc > index 12f27bb..5d3ec9a 100644 > --- a/core/dhcp.cc > +++ b/core/dhcp.cc > @@ -253,12 +253,16 @@ namespace dhcp { > ip::address_v4::bytes_type dhcp_server_ip = sip.to_bytes(); > ip::address_v4::bytes_type requested_ip = yip.to_bytes(); > options = add_option(options, DHCP_OPTION_MESSAGE_TYPE, 1, > DHCP_MT_REQUEST); > - options = add_option(options, DHCP_OPTION_DHCP_SERVER, 4, > (u8*)&dhcp_server_ip); > + if(request_packet_type == DHCP_REQUEST_SELECTING) { > + options = add_option(options, DHCP_OPTION_DHCP_SERVER, 4, > (u8*)&dhcp_server_ip); > + } > char hostname[256]; > if (0 == gethostname(hostname, sizeof(hostname))) { > options = add_option(options, DHCP_OPTION_HOSTNAME, > strlen(hostname), (u8*)hostname); > } > - options = add_option(options, DHCP_OPTION_REQUESTED_ADDRESS, 4, > (u8*)&requested_ip); > + if(request_packet_type == DHCP_REQUEST_SELECTING) { > + options = add_option(options, DHCP_OPTION_REQUESTED_ADDRESS, > 4, (u8*)&requested_ip); > + } > options = add_option(options, DHCP_OPTION_PARAMETER_REQUEST_LIST, > sizeof(requested_options), requested_options); > *options++ = DHCP_OPTION_END; > > > > ----- Original Message ----- > > From: "Waldek Kozaczuk" <[email protected]> > > To: "Nadav Har'El" <[email protected]> > > Cc: "justinc1" <[email protected]>, "Osv Dev" < > [email protected]> > > Sent: Wednesday, March 22, 2017 2:54:43 PM > > Subject: Re: [PATCH] Changed DHCP client logic to properly broadcast > DHCPREQUEST during > > > > I forgot to mention that I tested this patch on both VMware with InfoBlox > > DHCP server and EC2. > > > > Sent from my iPhone > > > > > On Mar 22, 2017, at 09:18, Nadav Har'El <[email protected]> wrote: > > > > > > Thanks. Looks good to me. Justin, can you please also have a look? > > > > > > > > > -- > > > Nadav Har'El > > > [email protected] > > > > > >> On Wed, Mar 22, 2017 at 2:57 PM, Waldemar Kozaczuk < > [email protected]> > > >> wrote: > > >> From: wkozaczuk <[email protected]> > > >> > > >> The patch addressing issue #816 changed dhcp_mbuf::compose_request() > > >> method to > > >> make it unicast DHCPREQUEST message to a DHCP server. This is > incorrect > > >> per RCF-2131 > > >> which requires DHCP clients to broadcast messages until IP address is > > >> bound which > > >> is a case during RENEWING phase but not SELECTING one. Now the > > >> dhcp_mbuf::compose_request() > > >> takes extra enum parameter which specifies which phase (per page 34 of > > >> https://www.ietf.org/rfc/rfc2131.txt) > > >> the message is being composed for. > > >> > > >> Fixes #864 > > >> > > >> Signed-off-by: Waldemar Kozaczuk <[email protected]> > > >> --- > > >> core/dhcp.cc | 55 > > >> ++++++++++++++++++++++++++++++++++++++++++++++------- > > >> include/osv/dhcp.hh | 10 +++++++++- > > >> 2 files changed, 57 insertions(+), 8 deletions(-) > > >> > > >> diff --git a/core/dhcp.cc b/core/dhcp.cc > > >> index 1b90adb..12f27bb 100644 > > >> --- a/core/dhcp.cc > > >> +++ b/core/dhcp.cc > > >> @@ -81,11 +81,26 @@ namespace dhcp { > > >> > > >> const char * dhcp_options_magic = "\x63\x82\x53\x63"; > > >> > > >> + static std::map<dhcp_message_type,const char*> > > >> dhcp_message_type_name_by_id = { > > >> + {DHCP_MT_DISCOVER, "DHCPDISCOVER"}, > > >> + {DHCP_MT_OFFER, "DHCPOFFER"}, > > >> + {DHCP_MT_REQUEST, "DHCPREQUEST"}, > > >> + {DHCP_MT_DECLINE, "DHCPDECLINE"}, > > >> + {DHCP_MT_ACK, "DHCPACK"}, > > >> + {DHCP_MT_NAK, "DHCPNAK"}, > > >> + {DHCP_MT_RELEASE, "DHCPRELEASE"}, > > >> + {DHCP_MT_INFORM, "DHCPINFORM"}, > > >> + {DHCP_MT_LEASEQUERY, "DHCPLEASEQUERY"}, > > >> + {DHCP_MT_LEASEUNASSIGNED, "DHCPLEASEUNASSIGNED"}, > > >> + {DHCP_MT_LEASEUNKNOWN, "DHCPLEASEUNKNOWN"}, > > >> + {DHCP_MT_LEASEACTIVE, "DHCPLEASEACTIVE"}, > > >> + {DHCP_MT_INVALID, "DHCPINVALID"} > > >> + }; > > >> + > > >> //////////////////////////////////////////////////////////// > /////////////// > > >> > > >> bool dhcp_socket::dhcp_send(dhcp_mbuf& packet) > > >> { > > >> - > > >> struct bsd_sockaddr dst = {}; > > >> struct mbuf *m = packet.get(); > > >> > > >> @@ -205,7 +220,8 @@ namespace dhcp { > > >> void dhcp_mbuf::compose_request(struct ifnet* ifp, > > >> u32 xid, > > >> ip::address_v4 yip, > > >> - ip::address_v4 sip) > > >> + ip::address_v4 sip, > > >> + dhcp_request_packet_type > > >> request_packet_type) > > >> { > > >> size_t dhcp_len = sizeof(struct dhcp_packet); > > >> struct dhcp_packet* pkt = pdhcp(); > > >> @@ -222,7 +238,11 @@ namespace dhcp { > > >> memcpy(pkt->chaddr, IF_LLADDR(ifp), ETHER_ADDR_LEN); > > >> ulong yip_n = htonl(yip.to_ulong()); > > >> ulong sip_n = htonl(sip.to_ulong()); > > >> - memcpy(&pkt->ciaddr.s_addr, &yip_n, 4); > > >> + if(request_packet_type == DHCP_REQUEST_RENEWING || > > >> request_packet_type == DHCP_REQUEST_REBINDING) { > > >> + // ciaddr should only be set to if RENEWING or REBINDING > > >> + // See pages 21 and 30-31 in > > >> https://www.ietf.org/rfc/rfc2131.txt > > >> + memcpy(&pkt->ciaddr.s_addr, &yip_n, 4); > > >> + } > > >> > > >> // Options > > >> u8* options_start = reinterpret_cast<u8*>(pkt+1); > > >> @@ -244,7 +264,14 @@ namespace dhcp { > > >> *options++ = DHCP_OPTION_END; > > >> > > >> dhcp_len += options - options_start; > > >> - build_udp_ip_headers(dhcp_len, yip_n, sip_n); > > >> + > > >> + // See page 33 in https://www.ietf.org/rfc/rfc2131.txt > > >> + if(request_packet_type == DHCP_REQUEST_RENEWING) { > > >> + build_udp_ip_headers(dhcp_len, yip_n, sip_n); > > >> + } > > >> + else { > > >> + build_udp_ip_headers(dhcp_len, INADDR_ANY, > INADDR_BROADCAST); > > >> + } > > >> } > > >> > > >> void dhcp_mbuf::compose_release(struct ifnet* ifp, > > >> @@ -420,6 +447,9 @@ namespace dhcp { > > >> options += op_len; > > >> } > > >> > > >> + dhcp_i( "Received %s message from DHCP server: %s regarding > > >> offerred IP address: %s", > > >> + dhcp_message_type_name_by_id[_message_type], > > >> _dhcp_server_ip.to_string().c_str(), > > >> + _your_ip.to_string().c_str()); > > >> return true; > > >> } > > >> > > >> @@ -519,6 +549,7 @@ namespace dhcp { > > >> // Save transaction id & send > > >> _xid = dm.get_xid(); > > >> _client_addr = _server_addr = ipv4_zero; > > >> + dhcp_i( "Broadcasting DHCPDISCOVER message with xid: > [%d]",_xid); > > >> _sock->dhcp_send(dm); > > >> } > > >> > > >> @@ -533,6 +564,8 @@ namespace dhcp { > > >> > > >> // Save transaction id & send > > >> _xid = dm.get_xid(); > > >> + dhcp_i( "Unicasting DHCPRELEASE message with xid: [%d] from > > >> client: %s to server: %s", > > >> + _xid, _client_addr.to_string().c_str(), > > >> _server_addr.to_string().c_str()); > > >> _sock->dhcp_send(dm); > > >> // IP and routes have to be removed > > >> osv::stop_if(_ifp->if_xname, _client_addr.to_string().c_ > str()); > > >> @@ -553,9 +586,13 @@ namespace dhcp { > > >> _xid = rand(); > > >> dm.compose_request(_ifp, > > >> _xid, > > >> - _client_addr, _server_addr); > > >> + _client_addr, > > >> + _server_addr, > > >> + dhcp_mbuf::DHCP_REQUEST_RENEWING); > > >> > > >> // Send > > >> + dhcp_i( "Unicasting DHCPREQUEST message with xid: [%d] from > > >> client: %s to server: %s in order to RENEW lease of: %s", > > >> + _xid, _client_addr.to_string().c_str(), > > >> _server_addr.to_string().c_str(), _client_addr.to_string().c_str()); > > >> _sock->dhcp_send(dm); > > >> } > > >> > > >> @@ -600,14 +637,18 @@ namespace dhcp { > > >> dm_req.compose_request(_ifp, > > >> _xid, > > >> dm.get_your_ip(), > > >> - dm.get_dhcp_server_ip()); > > >> + dm.get_dhcp_server_ip(), > > >> + dhcp_mbuf::DHCP_REQUEST_SELECTING); > > >> + dhcp_i( "Broadcasting DHCPREQUEST message with xid: [%d] to > > >> SELECT offered IP: %s", > > >> + _xid, dm.get_your_ip().to_string().c_str()); > > >> _sock->dhcp_send(dm_req); > > >> } > > >> > > >> void dhcp_interface_state::state_request(dhcp_mbuf &dm) > > >> { > > >> if (dm.get_message_type() == DHCP_MT_ACK) { > > >> - dhcp_i("Server acknowledged IP for interface %s", > > >> _ifp->if_xname); > > >> + dhcp_i("Server acknowledged IP %s for interface %s with > time > > >> to lease in seconds: %d", > > >> + dm.get_your_ip().to_string().c_str(), > _ifp->if_xname, > > >> dm.get_lease_time_sec()); > > >> _state = DHCP_ACKNOWLEDGE; > > >> _client_addr = dm.get_your_ip(); > > >> _server_addr = dm.get_dhcp_server_ip(); > > >> diff --git a/include/osv/dhcp.hh b/include/osv/dhcp.hh > > >> index 3db6df8..6797b7f 100644 > > >> --- a/include/osv/dhcp.hh > > >> +++ b/include/osv/dhcp.hh > > >> @@ -117,6 +117,13 @@ namespace dhcp { > > >> DHCP_REPLY = 2, > > >> }; > > >> > > >> + enum dhcp_request_packet_type { > > >> + DHCP_REQUEST_INIT_REBOOT = 1, > > >> + DHCP_REQUEST_SELECTING = 2, > > >> + DHCP_REQUEST_RENEWING = 3, > > >> + DHCP_REQUEST_REBINDING = 4, > > >> + }; > > >> + > > >> dhcp_mbuf(bool attached = true, struct mbuf* m = nullptr); > > >> ~dhcp_mbuf(); > > >> > > >> @@ -129,7 +136,8 @@ namespace dhcp { > > >> void compose_request(struct ifnet* ifp, > > >> u32 xid, > > >> boost::asio::ip::address_v4 yip, > > >> - boost::asio::ip::address_v4 sip); > > >> + boost::asio::ip::address_v4 sip, > > >> + dhcp_request_packet_type > > >> request_packet_type); > > >> void compose_release(struct ifnet* ifp, > > >> boost::asio::ip::address_v4 yip, > > >> boost::asio::ip::address_v4 sip); > > >> -- > > >> 2.7.4 > > >> > > >> -- > > >> You received this message because you are subscribed to the Google > Groups > > >> "OSv Development" group. > > >> To unsubscribe from this group and stop receiving emails from it, > send an > > >> email to [email protected]. > > >> For more options, visit https://groups.google.com/d/optout. > > > > > > -- You received this message because you are subscribed to the Google Groups "OSv Development" group. 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