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- // SPDX-License-Identifier: GPL-2.0+
- /*
- * Copyright (C) Microsoft Corporation
- * Author: Sean Edmond <seanedmond@microsoft.com>
- *
- */
- /* Simple DHCP6 network layer implementation. */
- #include <common.h>
- #include <net6.h>
- #include <malloc.h>
- #include <linux/delay.h>
- #include "net_rand.h"
- #include "dhcpv6.h"
- #define PORT_DHCP6_S 547 /* DHCP6 server UDP port */
- #define PORT_DHCP6_C 546 /* DHCP6 client UDP port */
- /* default timeout parameters (in ms) */
- #define SOL_MAX_DELAY_MS 1000
- #define SOL_TIMEOUT_MS 1000
- #define SOL_MAX_RT_MS 3600000
- #define REQ_TIMEOUT_MS 1000
- #define REQ_MAX_RT_MS 30000
- #define REQ_MAX_RC 10
- #define MAX_WAIT_TIME_MS 60000
- /* global variable to track any updates from DHCP6 server */
- int updated_sol_max_rt_ms = SOL_MAX_RT_MS;
- /* state machine parameters/variables */
- struct dhcp6_sm_params sm_params;
- static void dhcp6_state_machine(bool timeout, uchar *rx_pkt, unsigned int len);
- /* Handle DHCP received packets (set as UDP handler) */
- static void dhcp6_handler(uchar *pkt, unsigned int dest, struct in_addr sip,
- unsigned int src, unsigned int len)
- {
- /* return if ports don't match DHCPv6 ports */
- if (dest != PORT_DHCP6_C || src != PORT_DHCP6_S)
- return;
- dhcp6_state_machine(false, pkt, len);
- }
- /**
- * dhcp6_add_option() - Adds DHCP6 option to a packet
- * @option_id: The option ID to add (See DHCP6_OPTION_* definitions)
- * @pkt: A pointer to the current write location of the TX packet
- *
- * Return: The number of bytes written into "*pkt"
- */
- static int dhcp6_add_option(int option_id, uchar *pkt)
- {
- struct dhcp6_option_duid_ll *duid_opt;
- struct dhcp6_option_elapsed_time *elapsed_time_opt;
- struct dhcp6_option_ia_ta *ia_ta_opt;
- struct dhcp6_option_ia_na *ia_na_opt;
- struct dhcp6_option_oro *oro_opt;
- struct dhcp6_option_client_arch *client_arch_opt;
- struct dhcp6_option_vendor_class *vendor_class_opt;
- int opt_len;
- long elapsed_time;
- size_t vci_strlen;
- int num_oro = 0;
- int num_client_arch = 0;
- int num_vc_data = 0;
- struct dhcp6_option_hdr *dhcp_option = (struct dhcp6_option_hdr *)pkt;
- uchar *dhcp_option_start = pkt + sizeof(struct dhcp6_option_hdr);
- dhcp_option->option_id = htons(option_id);
- switch (option_id) {
- case DHCP6_OPTION_CLIENTID:
- /* Only support for DUID-LL in Client ID option for now */
- duid_opt = (struct dhcp6_option_duid_ll *)dhcp_option_start;
- duid_opt->duid_type = htons(DUID_TYPE_LL);
- duid_opt->hw_type = htons(DUID_HW_TYPE_ENET);
- memcpy(duid_opt->ll_addr, net_ethaddr, ETH_ALEN);
- opt_len = sizeof(struct dhcp6_option_duid_ll) + ETH_ALEN;
- /* Save DUID for comparison later */
- memcpy(sm_params.duid, duid_opt, opt_len);
- break;
- case DHCP6_OPTION_ELAPSED_TIME:
- /* calculate elapsed time in 1/100th of a second */
- elapsed_time = (sm_params.dhcp6_retry_ms -
- sm_params.dhcp6_start_ms) / 10;
- if (elapsed_time > 0xFFFF)
- elapsed_time = 0xFFFF;
- elapsed_time_opt = (struct dhcp6_option_elapsed_time *)dhcp_option_start;
- elapsed_time_opt->elapsed_time = htons(elapsed_time);
- opt_len = sizeof(struct dhcp6_option_elapsed_time);
- break;
- case DHCP6_OPTION_IA_TA:
- ia_ta_opt = (struct dhcp6_option_ia_ta *)dhcp_option_start;
- ia_ta_opt->iaid = htonl(sm_params.ia_id);
- opt_len = sizeof(struct dhcp6_option_ia_ta);
- break;
- case DHCP6_OPTION_IA_NA:
- ia_na_opt = (struct dhcp6_option_ia_na *)dhcp_option_start;
- ia_na_opt->iaid = htonl(sm_params.ia_id);
- /* In a message sent by a client to a server,
- * the T1 and T2 fields SHOULD be set to 0
- */
- ia_na_opt->t1 = 0;
- ia_na_opt->t2 = 0;
- opt_len = sizeof(struct dhcp6_option_ia_na);
- break;
- case DHCP6_OPTION_ORO:
- oro_opt = (struct dhcp6_option_oro *)dhcp_option_start;
- oro_opt->req_option_code[num_oro++] = htons(DHCP6_OPTION_OPT_BOOTFILE_URL);
- oro_opt->req_option_code[num_oro++] = htons(DHCP6_OPTION_SOL_MAX_RT);
- if (IS_ENABLED(CONFIG_DHCP6_PXE_DHCP_OPTION)) {
- oro_opt->req_option_code[num_oro++] =
- htons(DHCP6_OPTION_OPT_BOOTFILE_PARAM);
- }
- opt_len = sizeof(__be16) * num_oro;
- break;
- case DHCP6_OPTION_CLIENT_ARCH_TYPE:
- client_arch_opt = (struct dhcp6_option_client_arch *)dhcp_option_start;
- client_arch_opt->arch_type[num_client_arch++] = htons(CONFIG_DHCP6_PXE_CLIENTARCH);
- opt_len = sizeof(__be16) * num_client_arch;
- break;
- case DHCP6_OPTION_VENDOR_CLASS:
- vendor_class_opt = (struct dhcp6_option_vendor_class *)dhcp_option_start;
- vendor_class_opt->enterprise_number = htonl(CONFIG_DHCP6_ENTERPRISE_ID);
- vci_strlen = strlen(DHCP6_VCI_STRING);
- vendor_class_opt->vendor_class_data[num_vc_data].vendor_class_len =
- htons(vci_strlen);
- memcpy(vendor_class_opt->vendor_class_data[num_vc_data].opaque_data,
- DHCP6_VCI_STRING, vci_strlen);
- num_vc_data++;
- opt_len = sizeof(struct dhcp6_option_vendor_class) +
- sizeof(struct vendor_class_data) * num_vc_data +
- vci_strlen;
- break;
- case DHCP6_OPTION_NII:
- dhcp_option_start[0] = 1;
- dhcp_option_start[1] = 0;
- dhcp_option_start[2] = 0;
- opt_len = 3;
- break;
- default:
- printf("***Warning unknown DHCP6 option %d. Not adding to message\n", option_id);
- return 0;
- }
- dhcp_option->option_len = htons(opt_len);
- return opt_len + sizeof(struct dhcp6_option_hdr);
- }
- /**
- * dhcp6_send_solicit_packet() - Send a SOLICIT packet
- *
- * Implements RFC 8415:
- * - 16.2. Solicit Message
- * - 18.2.1. Creation and Transmission of Solicit Messages
- *
- * Adds DHCP6 header and DHCP6 options. Sends the UDP packet
- * and sets the UDP handler.
- */
- static void dhcp6_send_solicit_packet(void)
- {
- struct in6_addr dhcp_bcast_ip6;
- int len = 0;
- uchar *pkt;
- uchar *dhcp_pkt_start_ptr;
- struct dhcp6_hdr *dhcp_hdr;
- pkt = net_tx_packet + net_eth_hdr_size() + IP6_HDR_SIZE + UDP_HDR_SIZE;
- dhcp_pkt_start_ptr = pkt;
- /* Add the DHCP6 header */
- dhcp_hdr = (struct dhcp6_hdr *)pkt;
- dhcp_hdr->msg_type = DHCP6_MSG_SOLICIT;
- dhcp_hdr->trans_id = htons(sm_params.trans_id);
- pkt += sizeof(struct dhcp6_hdr);
- /* Add the options */
- pkt += dhcp6_add_option(DHCP6_OPTION_CLIENTID, pkt);
- pkt += dhcp6_add_option(DHCP6_OPTION_ELAPSED_TIME, pkt);
- pkt += dhcp6_add_option(DHCP6_OPTION_IA_NA, pkt);
- pkt += dhcp6_add_option(DHCP6_OPTION_ORO, pkt);
- if (CONFIG_DHCP6_PXE_CLIENTARCH != 0xFF)
- pkt += dhcp6_add_option(DHCP6_OPTION_CLIENT_ARCH_TYPE, pkt);
- pkt += dhcp6_add_option(DHCP6_OPTION_VENDOR_CLASS, pkt);
- pkt += dhcp6_add_option(DHCP6_OPTION_NII, pkt);
- /* calculate packet length */
- len = pkt - dhcp_pkt_start_ptr;
- /* send UDP packet to DHCP6 multicast address */
- string_to_ip6(DHCP6_MULTICAST_ADDR, sizeof(DHCP6_MULTICAST_ADDR), &dhcp_bcast_ip6);
- net_set_udp_handler(dhcp6_handler);
- net_send_udp_packet6((uchar *)net_bcast_ethaddr, &dhcp_bcast_ip6,
- PORT_DHCP6_S, PORT_DHCP6_C, len);
- }
- /**
- * dhcp6_send_request_packet() - Send a REQUEST packet
- *
- * * Implements RFC 8415:
- * - 16.4. Request Message
- * - 18.2.2. Creation and Transmission of Request Messages
- *
- * Adds DHCP6 header and DHCP6 options. Sends the UDP packet
- * and sets the UDP handler.
- */
- static void dhcp6_send_request_packet(void)
- {
- struct in6_addr dhcp_bcast_ip6;
- int len = 0;
- uchar *pkt;
- uchar *dhcp_pkt_start_ptr;
- struct dhcp6_hdr *dhcp_hdr;
- pkt = net_tx_packet + net_eth_hdr_size() + IP6_HDR_SIZE + UDP_HDR_SIZE;
- dhcp_pkt_start_ptr = pkt;
- /* Add the DHCP6 header */
- dhcp_hdr = (struct dhcp6_hdr *)pkt;
- dhcp_hdr->msg_type = DHCP6_MSG_REQUEST;
- dhcp_hdr->trans_id = htons(sm_params.trans_id);
- pkt += sizeof(struct dhcp6_hdr);
- /* add the options */
- pkt += dhcp6_add_option(DHCP6_OPTION_CLIENTID, pkt);
- pkt += dhcp6_add_option(DHCP6_OPTION_ELAPSED_TIME, pkt);
- pkt += dhcp6_add_option(DHCP6_OPTION_IA_NA, pkt);
- pkt += dhcp6_add_option(DHCP6_OPTION_ORO, pkt);
- /* copy received IA_TA/IA_NA into the REQUEST packet */
- if (sm_params.server_uid.uid_ptr) {
- memcpy(pkt, sm_params.server_uid.uid_ptr, sm_params.server_uid.uid_size);
- pkt += sm_params.server_uid.uid_size;
- }
- if (CONFIG_DHCP6_PXE_CLIENTARCH != 0xFF)
- pkt += dhcp6_add_option(DHCP6_OPTION_CLIENT_ARCH_TYPE, pkt);
- pkt += dhcp6_add_option(DHCP6_OPTION_VENDOR_CLASS, pkt);
- pkt += dhcp6_add_option(DHCP6_OPTION_NII, pkt);
- /* calculate packet length */
- len = pkt - dhcp_pkt_start_ptr;
- /* send UDP packet to DHCP6 multicast address */
- string_to_ip6(DHCP6_MULTICAST_ADDR, strlen(DHCP6_MULTICAST_ADDR), &dhcp_bcast_ip6);
- net_set_udp_handler(dhcp6_handler);
- net_send_udp_packet6((uchar *)net_bcast_ethaddr, &dhcp_bcast_ip6,
- PORT_DHCP6_S, PORT_DHCP6_C, len);
- }
- static void dhcp6_parse_ia_options(struct dhcp6_option_hdr *ia_ptr, uchar *ia_option_ptr)
- {
- struct dhcp6_option_hdr *ia_option_hdr;
- ia_option_hdr = (struct dhcp6_option_hdr *)ia_option_ptr;
- /* Search for options encapsulated in IA_NA/IA_TA (DHCP6_OPTION_IAADDR
- * or DHCP6_OPTION_STATUS_CODE)
- */
- while (ia_option_ptr < ((uchar *)ia_ptr + ntohs(ia_ptr->option_len))) {
- switch (ntohs(ia_option_hdr->option_id)) {
- case DHCP6_OPTION_IAADDR:
- sm_params.rx_status.ia_addr_found = true;
- net_copy_ip6(&sm_params.rx_status.ia_addr_ipv6,
- (ia_option_ptr + sizeof(struct dhcp6_hdr)));
- debug("DHCP6_OPTION_IAADDR FOUND\n");
- break;
- case DHCP6_OPTION_STATUS_CODE:
- sm_params.rx_status.ia_status_code =
- ntohs(*((u16 *)(ia_option_ptr + sizeof(struct dhcp6_hdr))));
- printf("ERROR : IA STATUS %d\n", sm_params.rx_status.ia_status_code);
- break;
- default:
- debug("Unknown Option in IA, skipping\n");
- break;
- }
- ia_option_ptr += ntohs(((struct dhcp6_option_hdr *)ia_option_ptr)->option_len);
- }
- }
- /**
- * dhcp6_parse_options() - Parse the DHCP6 options
- *
- * @rx_pkt: pointer to beginning of received DHCP6 packet
- * @len: Total length of the DHCP6 packet
- *
- * Parses the DHCP options from a received DHCP packet. Perform error checking
- * on the options received. Any relevant status is available in:
- * "sm_params.rx_status"
- *
- */
- static void dhcp6_parse_options(uchar *rx_pkt, unsigned int len)
- {
- uchar *option_ptr;
- int sol_max_rt_sec, option_len;
- char *s, *e;
- struct dhcp6_option_hdr *option_hdr;
- memset(&sm_params.rx_status, 0, sizeof(struct dhcp6_rx_pkt_status));
- option_hdr = (struct dhcp6_option_hdr *)(rx_pkt + sizeof(struct dhcp6_hdr));
- /* check that required options exist */
- while (option_hdr < (struct dhcp6_option_hdr *)(rx_pkt + len)) {
- option_ptr = ((uchar *)option_hdr) + sizeof(struct dhcp6_hdr);
- option_len = ntohs(option_hdr->option_len);
- if (option_ptr + option_len > rx_pkt + len) {
- debug("Invalid option length\n");
- return;
- }
- switch (ntohs(option_hdr->option_id)) {
- case DHCP6_OPTION_CLIENTID:
- if (memcmp(option_ptr, sm_params.duid, option_len)
- != 0) {
- debug("CLIENT ID DOESN'T MATCH\n");
- } else {
- debug("CLIENT ID FOUND and MATCHES\n");
- sm_params.rx_status.client_id_match = true;
- }
- break;
- case DHCP6_OPTION_SERVERID:
- sm_params.rx_status.server_id_found = true;
- sm_params.rx_status.server_uid_ptr = (uchar *)option_hdr;
- sm_params.rx_status.server_uid_size = option_len +
- sizeof(struct dhcp6_option_hdr);
- debug("SERVER ID FOUND\n");
- break;
- case DHCP6_OPTION_IA_TA:
- case DHCP6_OPTION_IA_NA:
- /* check the IA_ID */
- if (*((u32 *)option_ptr) != htonl(sm_params.ia_id)) {
- debug("IA_ID mismatch 0x%08x 0x%08x\n",
- *((u32 *)option_ptr), htonl(sm_params.ia_id));
- break;
- }
- if (ntohs(option_hdr->option_id) == DHCP6_OPTION_IA_NA) {
- /* skip past IA_ID/T1/T2 */
- option_ptr += 3 * sizeof(u32);
- } else if (ntohs(option_hdr->option_id) == DHCP6_OPTION_IA_TA) {
- /* skip past IA_ID */
- option_ptr += sizeof(u32);
- }
- /* parse the IA_NA/IA_TA encapsulated options */
- dhcp6_parse_ia_options(option_hdr, option_ptr);
- break;
- case DHCP6_OPTION_STATUS_CODE:
- debug("DHCP6_OPTION_STATUS_CODE FOUND\n");
- sm_params.rx_status.status_code = ntohs(*((u16 *)option_ptr));
- debug("DHCP6 top-level status code %d\n", sm_params.rx_status.status_code);
- debug("DHCP6 status message: %.*s\n", len, option_ptr + 2);
- break;
- case DHCP6_OPTION_SOL_MAX_RT:
- debug("DHCP6_OPTION_SOL_MAX_RT FOUND\n");
- sol_max_rt_sec = ntohl(*((u32 *)option_ptr));
- /* A DHCP client MUST ignore any SOL_MAX_RT option values that are less
- * than 60 or more than 86400
- */
- if (sol_max_rt_sec >= 60 && sol_max_rt_sec <= 86400) {
- updated_sol_max_rt_ms = sol_max_rt_sec * 1000;
- if (sm_params.curr_state == DHCP6_SOLICIT)
- sm_params.mrt_ms = updated_sol_max_rt_ms;
- }
- break;
- case DHCP6_OPTION_OPT_BOOTFILE_URL:
- debug("DHCP6_OPTION_OPT_BOOTFILE_URL FOUND\n");
- copy_filename(net_boot_file_name, option_ptr, option_len + 1);
- debug("net_boot_file_name: %s\n", net_boot_file_name);
- /* copy server_ip6 (required for PXE) */
- s = strchr(net_boot_file_name, '[');
- e = strchr(net_boot_file_name, ']');
- if (s && e && e > s)
- string_to_ip6(s + 1, e - s - 1, &net_server_ip6);
- break;
- case DHCP6_OPTION_OPT_BOOTFILE_PARAM:
- if (IS_ENABLED(CONFIG_DHCP6_PXE_DHCP_OPTION)) {
- debug("DHCP6_OPTION_OPT_BOOTFILE_PARAM FOUND\n");
- if (pxelinux_configfile)
- free(pxelinux_configfile);
- pxelinux_configfile = (char *)malloc((option_len + 1) *
- sizeof(char));
- if (pxelinux_configfile)
- strlcpy(pxelinux_configfile, option_ptr, option_len + 1);
- else
- printf("Error: Failed to allocate pxelinux_configfile\n");
- debug("PXE CONFIG FILE %s\n", pxelinux_configfile);
- }
- break;
- case DHCP6_OPTION_PREFERENCE:
- debug("DHCP6_OPTION_PREFERENCE FOUND\n");
- sm_params.rx_status.preference = *option_ptr;
- break;
- default:
- debug("Unknown Option ID: %d, skipping parsing\n",
- ntohs(option_hdr->option_id));
- break;
- }
- /* Increment to next option header */
- option_hdr = (struct dhcp6_option_hdr *)(((uchar *)option_hdr) +
- sizeof(struct dhcp6_option_hdr) + option_len);
- }
- }
- /**
- * dhcp6_check_advertise_packet() - Perform error checking on an expected
- * ADVERTISE packet.
- *
- * @rx_pkt: pointer to beginning of received DHCP6 packet
- * @len: Total length of the DHCP6 packet
- *
- * Implements RFC 8415:
- * - 16.3. Advertise Message
- * - 18.2.10. Receipt of Reply Messages
- *
- * Return : 0 : ADVERTISE packet was received with no errors.
- * State machine can progress
- * 1 : - packet received is not an ADVERTISE packet
- * - there were errors in the packet received,
- * - this is the first SOLICIT packet, but
- * received preference is not 255, so we have
- * to wait for more server responses.
- */
- static int dhcp6_check_advertise_packet(uchar *rx_pkt, unsigned int len)
- {
- u16 rx_uid_size;
- struct dhcp6_hdr *dhcp6_hdr = (struct dhcp6_hdr *)rx_pkt;
- /* Ignore message if msg-type != advertise */
- if (dhcp6_hdr->msg_type != DHCP6_MSG_ADVERTISE)
- return 1;
- /* Ignore message if transaction ID doesn't match */
- if (dhcp6_hdr->trans_id != htons(sm_params.trans_id))
- return 1;
- dhcp6_parse_options(rx_pkt, len);
- /* Ignore advertise if any of these conditions met */
- if (!sm_params.rx_status.server_id_found ||
- !sm_params.rx_status.client_id_match ||
- sm_params.rx_status.status_code != DHCP6_SUCCESS) {
- return 1;
- }
- if (sm_params.rx_status.server_id_found) {
- /* if no server UID has been received yet, or if the server UID
- * received has a higher preference value than the currently saved
- * server UID, save the new server UID and preference
- */
- if (!sm_params.server_uid.uid_ptr ||
- (sm_params.server_uid.uid_ptr &&
- sm_params.server_uid.preference < sm_params.rx_status.preference)) {
- rx_uid_size = sm_params.rx_status.server_uid_size;
- if (sm_params.server_uid.uid_ptr)
- free(sm_params.server_uid.uid_ptr);
- sm_params.server_uid.uid_ptr = malloc(rx_uid_size * sizeof(uchar));
- if (sm_params.server_uid.uid_ptr)
- memcpy(sm_params.server_uid.uid_ptr,
- sm_params.rx_status.server_uid_ptr, rx_uid_size);
- sm_params.server_uid.uid_size = rx_uid_size;
- sm_params.server_uid.preference = sm_params.rx_status.preference;
- }
- /* If the first SOLICIT and preference code is 255, use right away.
- * Otherwise, wait for the first SOLICIT period for more
- * DHCP6 servers to respond.
- */
- if (sm_params.retry_cnt == 1 &&
- sm_params.server_uid.preference != 255) {
- debug("valid ADVERTISE, waiting for first SOLICIT period\n");
- return 1;
- }
- }
- return 0;
- }
- /**
- * dhcp6_check_reply_packet() - Perform error checking on an expected
- * REPLY packet.
- *
- * @rx_pkt: pointer to beginning of received DHCP6 packet
- * @len: Total length of the DHCP6 packet
- *
- * Implements RFC 8415:
- * - 16.10. Reply Message
- * - 18.2.10. Receipt of Reply Messages
- *
- * Return : 0 - REPLY packet was received with no errors
- * 1 - packet received is not an REPLY packet,
- * or there were errors in the packet received
- */
- static int dhcp6_check_reply_packet(uchar *rx_pkt, unsigned int len)
- {
- struct dhcp6_hdr *dhcp6_hdr = (struct dhcp6_hdr *)rx_pkt;
- /* Ignore message if msg-type != reply */
- if (dhcp6_hdr->msg_type != DHCP6_MSG_REPLY)
- return 1;
- /* check that transaction ID matches */
- if (dhcp6_hdr->trans_id != htons(sm_params.trans_id))
- return 1;
- dhcp6_parse_options(rx_pkt, len);
- /* if no addresses found, restart DHCP */
- if (!sm_params.rx_status.ia_addr_found ||
- sm_params.rx_status.ia_status_code == DHCP6_NO_ADDRS_AVAIL ||
- sm_params.rx_status.status_code == DHCP6_NOT_ON_LINK) {
- /* restart DHCP */
- debug("No address found in reply. Restarting DHCP\n");
- dhcp6_start();
- }
- /* ignore reply if any of these conditions met */
- if (!sm_params.rx_status.server_id_found ||
- !sm_params.rx_status.client_id_match ||
- sm_params.rx_status.status_code == DHCP6_UNSPEC_FAIL) {
- return 1;
- }
- return 0;
- }
- /* Timeout for DHCP6 SOLICIT/REQUEST */
- static void dhcp6_timeout_handler(void)
- {
- /* call state machine with the timeout flag */
- dhcp6_state_machine(true, NULL, 0);
- }
- /**
- * dhcp6_state_machine() - DHCP6 state machine
- *
- * @timeout: TRUE : timeout waiting for response from
- * DHCP6 server
- * FALSE : init or received response from DHCP6 server
- * @rx_pkt: Pointer to the beginning of received DHCP6 packet.
- * Will be NULL if called as part of init
- * or timeout==TRUE
- * @len: Total length of the DHCP6 packet if rx_pkt != NULL
- *
- * Implements RFC 8415:
- * - 5.2. Client/Server Exchanges Involving Four Messages
- * - 15. Reliability of Client-Initiated Message Exchanges
- *
- * Handles:
- * - transmission of SOLICIT and REQUEST packets
- * - retransmission of SOLICIT and REQUEST packets if no
- * response is received within the timeout window
- * - checking received ADVERTISE and REPLY packets to
- * assess if the DHCP state machine can progress
- */
- static void dhcp6_state_machine(bool timeout, uchar *rx_pkt, unsigned int len)
- {
- int rand_minus_plus_100;
- switch (sm_params.curr_state) {
- case DHCP6_INIT:
- sm_params.next_state = DHCP6_SOLICIT;
- break;
- case DHCP6_SOLICIT:
- if (!timeout) {
- /* check the rx packet and determine if we can transition to next
- * state.
- */
- if (dhcp6_check_advertise_packet(rx_pkt, len))
- return;
- debug("ADVERTISE good, transition to REQUEST\n");
- sm_params.next_state = DHCP6_REQUEST;
- } else if (sm_params.retry_cnt == 1) {
- /* If a server UID was received in the first SOLICIT period
- * transition to REQUEST
- */
- if (sm_params.server_uid.uid_ptr)
- sm_params.next_state = DHCP6_REQUEST;
- }
- break;
- case DHCP6_REQUEST:
- if (!timeout) {
- /* check the rx packet and determine if we can transition to next state */
- if (dhcp6_check_reply_packet(rx_pkt, len))
- return;
- debug("REPLY good, transition to DONE\n");
- sm_params.next_state = DHCP6_DONE;
- }
- break;
- case DHCP6_DONE:
- case DHCP6_FAIL:
- /* Shouldn't get here, as state machine should exit
- * immediately when DHCP6_DONE or DHCP6_FAIL is entered.
- * Proceed anyway to proceed DONE/FAIL actions
- */
- debug("Unexpected DHCP6 state : %d\n", sm_params.curr_state);
- break;
- }
- /* re-seed the RNG */
- srand(get_ticks() + rand());
- /* handle state machine entry conditions */
- if (sm_params.curr_state != sm_params.next_state) {
- sm_params.retry_cnt = 0;
- if (sm_params.next_state == DHCP6_SOLICIT) {
- /* delay a random ammount (special for SOLICIT) */
- udelay((rand() % SOL_MAX_DELAY_MS) * 1000);
- /* init timestamp variables after SOLICIT delay */
- sm_params.dhcp6_start_ms = get_timer(0);
- sm_params.dhcp6_retry_start_ms = sm_params.dhcp6_start_ms;
- sm_params.dhcp6_retry_ms = sm_params.dhcp6_start_ms;
- /* init transaction and ia_id */
- sm_params.trans_id = rand() & 0xFFFFFF;
- sm_params.ia_id = rand();
- /* initialize retransmission parameters */
- sm_params.irt_ms = SOL_TIMEOUT_MS;
- sm_params.mrt_ms = updated_sol_max_rt_ms;
- /* RFCs default MRC is be 0 (try infinitely)
- * give up after CONFIG_NET_RETRY_COUNT number of tries (same as DHCPv4)
- */
- sm_params.mrc = CONFIG_NET_RETRY_COUNT;
- sm_params.mrd_ms = 0;
- } else if (sm_params.next_state == DHCP6_REQUEST) {
- /* init timestamp variables */
- sm_params.dhcp6_retry_start_ms = get_timer(0);
- sm_params.dhcp6_retry_ms = sm_params.dhcp6_start_ms;
- /* initialize retransmission parameters */
- sm_params.irt_ms = REQ_TIMEOUT_MS;
- sm_params.mrt_ms = REQ_MAX_RT_MS;
- sm_params.mrc = REQ_MAX_RC;
- sm_params.mrd_ms = 0;
- }
- }
- if (timeout)
- sm_params.dhcp6_retry_ms = get_timer(0);
- /* Check if MRC or MRD have been passed */
- if ((sm_params.mrc != 0 &&
- sm_params.retry_cnt >= sm_params.mrc) ||
- (sm_params.mrd_ms != 0 &&
- ((sm_params.dhcp6_retry_ms - sm_params.dhcp6_retry_start_ms) >= sm_params.mrd_ms))) {
- sm_params.next_state = DHCP6_FAIL;
- }
- /* calculate retransmission timeout (RT) */
- rand_minus_plus_100 = ((rand() % 200) - 100);
- if (sm_params.retry_cnt == 0) {
- sm_params.rt_ms = sm_params.irt_ms +
- ((sm_params.irt_ms * rand_minus_plus_100) / 1000);
- } else {
- sm_params.rt_ms = (2 * sm_params.rt_prev_ms) +
- ((sm_params.rt_prev_ms * rand_minus_plus_100) / 1000);
- }
- if (sm_params.rt_ms > sm_params.mrt_ms) {
- sm_params.rt_ms = sm_params.mrt_ms +
- ((sm_params.mrt_ms * rand_minus_plus_100) / 1000);
- }
- sm_params.rt_prev_ms = sm_params.rt_ms;
- net_set_timeout_handler(sm_params.rt_ms, dhcp6_timeout_handler);
- /* send transmit/retransmit message or fail */
- sm_params.curr_state = sm_params.next_state;
- if (sm_params.curr_state == DHCP6_SOLICIT) {
- /* send solicit packet */
- dhcp6_send_solicit_packet();
- printf("DHCP6 SOLICIT %d\n", sm_params.retry_cnt);
- } else if (sm_params.curr_state == DHCP6_REQUEST) {
- /* send request packet */
- dhcp6_send_request_packet();
- printf("DHCP6 REQUEST %d\n", sm_params.retry_cnt);
- } else if (sm_params.curr_state == DHCP6_DONE) {
- net_set_timeout_handler(0, NULL);
- /* Duplicate address detection (DAD) should be
- * performed here before setting net_ip6
- * (enhancement should be considered)
- */
- net_copy_ip6(&net_ip6, &sm_params.rx_status.ia_addr_ipv6);
- printf("DHCP6 client bound to %pI6c\n", &net_ip6);
- /* will load with TFTP6 */
- net_auto_load();
- } else if (sm_params.curr_state == DHCP6_FAIL) {
- printf("DHCP6 FAILED, TERMINATING\n");
- net_set_state(NETLOOP_FAIL);
- }
- sm_params.retry_cnt++;
- }
- /* Start or restart DHCP6 */
- void dhcp6_start(void)
- {
- memset(&sm_params, 0, sizeof(struct dhcp6_sm_params));
- /* seed the RNG with MAC address */
- srand_mac();
- sm_params.curr_state = DHCP6_INIT;
- dhcp6_state_machine(false, NULL, 0);
- }
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