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icmp6.c
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icmp6.c
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/**
* This file is part of pgen, a packet generator tool.
* Copyright (C) 2013 Balakumaran Kannan <[email protected]>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "pgen.h"
struct icmp6_hdr{
char type;
char code;
int16_t checksum;
};
struct echo6_pkt {
uint16_t identifier;
uint16_t seq_num;
/**
* data is just a place holder. It only specifies the starting address.
* The entire value from ECHO6_DATA option will be dumped here.
* So user should take care of the buffer size.
*/
char data;
};
struct ndisc_ns_pkt {
/* 4-Byte reserved data */
uint32_t reserved;
char target_addr[16];
/**
* data is just a place holder. It only specifies the starting address.
* The entire value from NDISC_NS_OPTION option will be dumped here.
* So user should take care of the buffer size.
*/
char option;
};
struct ndisc_na_pkt {
/* R, S, O flag [1-bit each] and 29-bits resvered */
uint32_t RSO_res;
char target_addr[16];
/**
* data is just a place holder. It only specifies the starting address.
* The entire value from NDISC_NA_OPTION option will be dumped here.
* So user should take care of the buffer size.
*/
char option;
};
struct ndisc_rs_pkt {
/* 4-Byte reserved field */
uint32_t res;
/**
* data is just a place holder. It only specifies the starting address.
* The entire value from NDISC_RS_OPTION option will be dumped here.
* So user should take care of the buffer size.
*/
char option;
};
struct ndisc_ra_pkt {
char cur_hop_limit;
/* m(1) + o(1) + res(6) */
char m_o_res;
uint16_t router_lifetime;
uint32_t reachable_time;
uint32_t retrans_timer;
/**
* data is just a place holder. It only specifies the starting address.
* The entire value from NDISC_RA_OPTION option will be dumped here.
* So user should take care of the buffer size.
*/
char option;
};
/**
* @param pkt The packet buffer
* @param len length of the ICMPv6 packet
* @param fp file pointer to the configuration file
*
* @return
* 0 Success
* -1 Error
*
* @Description
* This function reads the ICMPv6 packet, calculates checksum and fills
* the checksum field in the packet.
* [RFC-4443]
* The checksum is the 16-bit one's complement of the one's complement sum of
* the entire ICMPv6 message, starting with the ICMPv6 message type field, and
* prepended with a "pseudo-header" of IPv6 header fields...
*/
int32_t calculate_icmp6_checksum(struct icmp6_hdr *pkt, int32_t len, FILE *fp) {
char option[MAX_OPTION_LEN], value[MAX_VALUE_LEN];
uint32_t checksum = 0;
int32_t init_pos, pos;
char src[16] = {0}, dst[16] = {0};
uint16_t *icmp6_pkt = (uint16_t *)pkt;
int32_t i;
/* store the current position of cursur in the conf file */
init_pos = ftell(fp);
if (init_pos < 0)
goto err;
/* Move cursur to the starting of conf file */
if (fseek(fp, 0, SEEK_SET))
goto err;
/* Find src and dst addresses that immediately above from current pos */
do {
if (pgen_parse_option(fp, option, value))
goto err;
pos = ftell(fp);
if (!strcmp(option, "IPV6_SRC_ADDR")) {
if (ip6_writer(src, value))
goto err;
}
else if (!strcmp(option, "IPV6_DST_ADDR")) {
if (ip6_writer(dst, value))
goto err;
}
} while ((pos != -1) && (pos < init_pos));
if (pos == -1)
goto err;
/* Process ipv6 src and dst addresses for checksum */
for (i = 0; i < 16; i += 2) {
checksum += (((src[i] & 0xff) << 8) | (src[i+1] & 0xff));
checksum += (((dst[i] & 0xff) << 8) | (dst[i+1] & 0xff));
}
/* process length of the icmpv6 message */
checksum += len;
/* Process packet type. Packet type is always icmpv6 */
checksum += 0x3a;
/* Process icmpv6 packet data */
while (len > 1) {
checksum += htons(*icmp6_pkt);
icmp6_pkt++;
len -= 2;
}
if (len > 0)
checksum += ((*(char *)icmp6_pkt) << 8);
/* Make it into 16 bits */
while (checksum >> 16 != 0)
checksum = (checksum & 0xffff) + (checksum >> 16);
/* One's complement */
checksum = ~checksum;
/**
* The checksum is the 16-bit one's complement of the one's complement
* sum of the entire ICMPv6 message starting with the ICMPv6 message
* type field, prepended with a "pseudo-header" of IPv6 header fields
* having only src addr, dst addr and packet type.
* [Ref: RFC-2463 same in RFC-4443]
*/
pkt->checksum = htons((uint16_t)checksum);
/* Restore the file position for furthur processing */
if (fseek(fp, init_pos, SEEK_SET))
goto err;
return 0;
err:
PGEN_INFO("Error while writing ICMPv6 checksum");
return -1;
}
/**
* @param fp file pointer to the configuration file
* @param cp_cur the packet buffer
*
* @return
* 0 Success
* -1 Error
*
* @Description
* Writes ICMPv6 echo6 packet
*/
char* pgen_echo6_writer(FILE *fp, char *cp_cur) {
struct echo6_pkt *pkt = (struct echo6_pkt *)cp_cur;
char option[MAX_OPTION_LEN], value[MAX_VALUE_LEN];
/**
* Three itmes need for an echo6 packet
*
* 1. Identifier
* 2. Sequence number
* 3. Data
*/
int32_t items = 3, tmp, len;
while (items--) {
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "ECHO6_IDENTIFIER")) {
if (pgen_store_num(&tmp, value))
goto err;
pkt->identifier = htons(tmp);
}
else if (!strcmp(option, "ECHO6_SEQ")) {
if (pgen_store_num(&tmp, value))
goto err;
pkt->seq_num = htons(tmp);
}
else if (!strcmp(option, "ECHO6_DATA")) {
if (!strcmp(value, "NO_DATA"))
len = 0;
else {
len = raw_data_writer(fp, &(pkt->data));
if (len == 0)
goto err;
}
}
}
return cp_cur + len + 4;
err:
PGEN_INFO("Error while writing echo6 packet");
return NULL;
}
/**
* @param fp file pointer to the configuration file
* @param cp_cur the packet buffer
*
* @return
* 0 Success
* -1 Error
*
* @Description
* Writes ICMPv6 Router Advertisement packet
*/
char* pgen_ndisc_ra_writer(FILE *fp, char *cp_cur) {
struct ndisc_ra_pkt *pkt = (struct ndisc_ra_pkt *)cp_cur;
char option[MAX_OPTION_LEN], value[MAX_VALUE_LEN];
/**
* Totally 7 items for packet
* 1. Cur_Hop_Limit - 1B
* 2. M flag - 1b
* 3. O flag - 1b
* 4. Router Lifetime - 2B
* 5. Reachable Time - 4B
* 6. Retrans Time - 4B
* 7. Option - variable length
*----------------------------
*
* And one for program control
* 8. Total number of options
*/
int32_t items = 8, tmp, op_len = 0, op_num;
char *op;
int32_t count, len, ret;
while (items--) {
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_CUR_HOP_LIMIT")) {
if (pgen_store_num(&tmp, value))
goto err;
pkt->cur_hop_limit = (char)tmp;
}
else if (!strcmp(option, "NDISC_RA_M_FLAG")) {
if (pgen_store_num(&tmp, value))
goto err;
if (tmp)
pkt->m_o_res |= 0x80;
}
else if (!strcmp(option, "NDISC_RA_O_FLAG")) {
if (pgen_store_num(&tmp, value))
goto err;
if (tmp)
pkt->m_o_res |= 0x40;
}
else if (!strcmp(option, "NDISC_RA_ROUTER_LIFETIME")) {
if (pgen_store_num(&tmp, value))
goto err;
pkt->router_lifetime = htons(tmp);
}
else if (!strcmp(option, "NDISC_RA_REACHABLE_TIME")) {
if (pgen_store_num(&tmp, value))
goto err;
pkt->reachable_time = htonl(tmp);
}
else if (!strcmp(option, "NDISC_RA_RETRANS_TIMER")) {
if (pgen_store_num(&tmp, value))
goto err;
pkt->retrans_timer = htonl(tmp);
}
else if (!strcmp(option, "NDISC_RA_OPTION_NUM")) {
if (pgen_store_num(&tmp, value))
goto err;
op_num = tmp;
}
else if (!strcmp(option, "NDISC_RA_OPTION")) {
op = &pkt->option;
/**
* Only three known options as of now [RFC-4681]
* 1. Source Link Address
* 2. Prefix Information
* 3. MTU
*
* From here the program expects the options to be in order
*/
while (op_num--) {
if (!strcmp(value, "NO_OPTION"))
op_len += 0;
/* Source Link Layer address */
else if (!strcmp(value, "NDISC_RA_SRC_LINK_ADDR")) {
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_OP_TYPE")) {
if (pgen_store_num(&tmp, value))
goto err;
*op = (char)tmp;
op++;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_OP_LEN")) {
if (pgen_store_num(&tmp, value))
goto err;
*op = (char)tmp;
/* Option length will be 8 octets unit */
op_len += tmp * 8;
op++;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_OP_SRC_LINK_ADDR")) {
if (mac_writer(op, value))
goto err;
op += 6;
}
else
goto err;
}
/* Prefix information */
else if (!strcmp(value, "NDISC_RA_PREFIX_INFO")) {
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_OP_TYPE")) {
if (pgen_store_num(&tmp, value))
goto err;
*op = (char)tmp;
op++;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_OP_LEN")) {
if (pgen_store_num(&tmp, value))
goto err;
*op = (char)tmp;
/* option length is in 8 octets uint */
op_len += tmp * 8;
op++;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_PREFIX_LEN")) {
if (pgen_store_num(&tmp, value))
goto err;
*op = (char)tmp;
op++;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_L_FLAG")) {
if (pgen_store_num(&tmp, value))
goto err;
if (tmp)
*op |= 0x80;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_A_FLAG")) {
if (pgen_store_num(&tmp, value))
goto err;
if (tmp)
*op |= 0x40;
}
else
goto err;
op++;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_PREFIX_VALID_LIFETIME")) {
if (pgen_store_num(&tmp, value))
goto err;
tmp = htonl(tmp);
memcpy(op, &tmp, 4);
op += 4;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_PREFIX_PREFERRED_LIFETIME")) {
if (pgen_store_num(&tmp, value))
goto err;
tmp = htonl(tmp);
memcpy(op, &tmp, 4);
op += 4;
}
else
goto err;
/* 4 Bytes Reserved */
op += 4;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_PREFIX")) {
if (ip6_prefix_writer(op, value))
goto err;
op += 16;
}
else
goto err;
}
/* MTU */
else if (!strcmp(value, "NDISC_RA_MTU")) {
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_OP_TYPE")) {
if (pgen_store_num(&tmp, value))
goto err;
*op = (char)tmp;
op++;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_OP_LEN")) {
if (pgen_store_num(&tmp, value))
goto err;
*op = (char)tmp;
/* Option length will be in 8 octets uint */
op_len += tmp * 8;
op++;
}
else
goto err;
/* 2-Bytes Reserverd */
op += 2;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_MTU")) {
if (pgen_store_num(&tmp, value))
goto err;
tmp = htonl(tmp);
memcpy(op, &tmp, 4);
op += 4;
}
else
goto err;
}
/* Recursive DNS Server Option. RFC-6106 */
else if (!strcmp(value, "NDISC_RA_RDNSS")) {
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_OP_TYPE")) {
if (pgen_store_num(&tmp, value))
goto err;
*op = (char)tmp;
op++;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_OP_LEN")) {
if (pgen_store_num(&tmp, value))
goto err;
*op = (char)tmp;
/* option len will be in 8 octets unit */
op_len += tmp * 8;
op++;
count = (tmp - 1) / 2;
}
else
goto err;
/* 2-Bytes reserved */
op += 2;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_OP_LIFETIME")) {
if (pgen_store_num(&tmp, value))
goto err;
tmp = htonl(tmp);
memcpy(op, &tmp, 4);
op += 4;
}
else
goto err;
while (count--) {
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_OP_DNS_ADDR")) {
if (ip6_writer(op, value))
goto err;
op += 16;
}
else
goto err;
}
}
/* DNS Search List Option. RFC-6106 */
else if (!strcmp(value, "NDISC_RA_DNSSL")) {
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_OP_TYPE")) {
if (pgen_store_num(&tmp, value))
goto err;
*op = (char)tmp;
op++;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_OP_LEN")) {
if (pgen_store_num(&tmp, value))
goto err;
*op = (char)tmp;
/* option length in 8-octet unit */
op_len += tmp * 8;
op++;
}
else
goto err;
/* 2-Bytes reserved */
op += 2;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_OP_LIFETIME")) {
if (pgen_store_num(&tmp, value))
goto err;
tmp = htonl(tmp);
memcpy(op, &tmp, 4);
op += 4;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_OP_NUM")) {
if (pgen_store_num(&count, value))
goto err;
}
else
goto err;
len = 0;
while(count--) {
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RA_OP_NAME")) {
ret = encode_name(op, value);
if (ret < 0)
goto err;
len += ret;
op += ret;
}
else
goto err;
}
/* pad to 8-octet multiple */
op += (8 - (len % 8));
}
/* RAW */
else if (!strcmp(value, "RAW")) {
tmp = raw_data_writer(fp, op);
if (tmp < 0)
goto err;
op_len += tmp;
op += tmp;
}
/* Unknown option */
else
goto err;
if (op_num && pgen_parse_option(fp, option, value))
goto err;
if (op_num && strcmp(option, "NDISC_RA_OPTION"))
goto err;
}
}
else
goto err;
}
/* length_of_packet(12) + op_len */
return (cp_cur + 12 + op_len);
err:
PGEN_INFO("Error while writing ND-RA packet");
PGEN_PRINT_DATA("Option: %s\tValue: %s\n", option, value);
return NULL;
}
/**
* @param fp file pointer to the configuration file
* @param cp_cur the packet buffer
*
* @return
* 0 Success
* -1 Error
*
* @Description
* Writes ICMPv6 Router Solicitation packet
*/
char* pgen_ndisc_rs_writer(FILE *fp, char *cp_cur) {
struct ndisc_rs_pkt *pkt = (struct ndisc_rs_pkt *)cp_cur;
char option[MAX_OPTION_LEN], value[MAX_VALUE_LEN];
char *op;
/**
* Having 1 item
* 1. Option - variable length
*/
int32_t tmp, op_len = 0, op_num;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RS_OP_NUM")) {
if (pgen_store_num(&tmp, value))
goto err;
op_num = tmp;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
/* Program expects the option to be in order */
if (!strcmp(option, "NDISC_RS_OPTION")) {
while (op_num--) {
if (!strcmp(value, "NO_OPTION"))
op_len += 0;
/* Source Link Layer address and the only known option */
else if (!strcmp(value, "NDISC_RS_SRC_LINK_ADDR")) {
op = (char *)&(pkt->option);
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RS_OP_TYPE")) {
if (pgen_store_num(&tmp, value))
goto err;
*op = (char)tmp;
op++;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RS_OP_LEN")) {
if (pgen_store_num(&tmp, value))
goto err;
*op = (char)tmp;
/* option length will be in 8 octets unit */
op_len += tmp * 8;
op++;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_RS_OP_SRC_LINK_ADDR")) {
if (mac_writer(op, value))
goto err;
op += 6;
}
else
goto err;
}
/* RAW */
else if (!strcmp(value, "RAW")) {
tmp = raw_data_writer(fp, op);
if (tmp < 0)
goto err;
op += tmp;
op_len += tmp;
}
/* Unknown option */
else
goto err;
if (op_num) {
if (pgen_parse_option(fp, option, value))
goto err;
if (strcmp(option, "NDISC_RS_OPTION"))
goto err;
}
}
}
else
goto err;
/* len = res(4) + op_len */
return (cp_cur + 4 + op_len);
err:
PGEN_INFO("Error while writing ICMPv6 RS packet");
PGEN_PRINT_DATA("%s\t%s\n", option, value);
return NULL;
}
/**
* @param fp File pointer to the configuration file
* @param cp_cur the packet buffer
*
* @returns
* 0 Success
* -1 Error
*
* @Description
* Writes ICMPv6 Neighbour Solicitation packet
*/
char* pgen_ndisc_ns_writer(FILE *fp, char *cp_cur) {
struct ndisc_ns_pkt *pkt = (struct ndisc_ns_pkt *)cp_cur;
char option[MAX_OPTION_LEN], value[MAX_VALUE_LEN];
char *op_ptr;
/**
* Having only two items.
*
* 1. Target address - 16B
* 2. Option - Variable length
*
* 3. Number of options
*/
int32_t items = 3, tmp, op_len = 0, op_num;
while (items--) {
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_NS_TARGET_ADDR")) {
if (ip6_writer(pkt->target_addr, value))
goto err;
}
else if (!strcmp(option, "NDISC_NS_OP_NUM")) {
if (pgen_store_num(&op_num, value))
goto err;
}
else if (!strcmp(option, "NDISC_NS_OPTION")) {
op_ptr = (char *)&(pkt->option);
/* Program expects the option to be in order */
while (op_num--) {
if (!strcmp(value, "NO_OPTION"))
op_len += 0;
/* This is only known option as of now. [RFC-4861] */
else if (!strcmp(value, "NDISC_NS_SRC_LINK_ADDR")) {
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_NS_OP_TYPE")) {
if (pgen_store_num(&tmp, value))
goto err;
*op_ptr = (char)tmp;
op_ptr++;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_NS_OP_LEN")) {
if (pgen_store_num(&tmp, value))
goto err;
*op_ptr = (char)tmp;
op_ptr++;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_NS_OP_SRC_LINK_ADDR")) {
if (mac_writer(op_ptr, value))
goto err;
op_ptr += 6;
}
else
goto err;
/* len is in 8 octets uint */
op_len += tmp * 8;
}
/* RAW */
else if (!strcmp(value, "RAW")) {
tmp = raw_data_writer(fp, op_ptr);
if (tmp < 0)
goto err;
op_ptr += tmp;
op_len += tmp;
}
/* Unknown option */
else
goto err;
if (op_num) {
if (pgen_parse_option(fp, option, value))
goto err;
if (strcmp(option, "NDISC_NS_OPTION"))
goto err;
}
}
}
else
goto err;
}
/* len = Reserved(4) + Target_addr(16) + op_len */
return (cp_cur + 4 + 16 + op_len);
err:
PGEN_INFO("Error while writing ICMPv6 NS packet");
PGEN_PRINT_DATA("%s\t%s\n", option, value);
return NULL;
}
/**
* @param fp file pointer to the configuration file
* @param cp_cur the packet buffer
*
* @return
* 0 Success
* -1 Error
*
* @Description
* Writes ICMPv6 Neighbour Advertisement packet
*/
char* pgen_ndisc_na_writer(FILE *fp, char *cp_cur) {
struct ndisc_na_pkt *pkt = (struct ndisc_na_pkt *)cp_cur;
char option[MAX_OPTION_LEN], value[MAX_VALUE_LEN];
char *op_ptr;
/**
* Totally 5 options
*
* 1. R Flag
* 2. S Flag
* 3. O Flag
* 4. Target addr
* 5. The option
*
* 6. Number of options
*/
int32_t items = 6, tmp, op_len = 0, op_num;
while (items--) {
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_NA_R")) {
if (pgen_store_num(&tmp, value))
goto err;
if (tmp)
pkt->RSO_res |= 0x80000000;
}
else if (!strcmp(option, "NDISC_NA_S")) {
if (pgen_store_num(&tmp, value))
goto err;
if (tmp)
pkt->RSO_res |= 0x40000000;
}
else if (!strcmp(option, "NDISC_NA_O")) {
if (pgen_store_num(&tmp, value))
goto err;
if (tmp)
pkt->RSO_res |= 0x20000000;
}
else if (!strcmp(option, "NDISC_NA_TARGET_ADDR")) {
if (ip6_writer(pkt->target_addr, value))
goto err;
}
else if (!strcmp(option, "NDISC_NA_OP_NUM")) {
if (pgen_store_num(&op_num, value))
goto err;
}
else if (!strcmp(option, "NDISC_NA_OPTION")) {
op_ptr = (char *)&(pkt->option);
while (op_num--) {
/* Program expects the options to be in order */
if (!strcmp(value, "NO_OPTION"))
op_len += 0;
/* This is only known option as of now. [RFC-4861] */
else if (!strcmp(value, "NDISC_NA_SRC_LINK_ADDR")) {
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_NA_OP_TYPE")) {
if (pgen_store_num(&tmp, value))
goto err;
*op_ptr = (char)tmp;
op_ptr++;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_NA_OP_LEN")) {
if (pgen_store_num(&tmp, value))
goto err;
*op_ptr = (char)tmp;
op_ptr++;
}
else
goto err;
if (pgen_parse_option(fp, option, value))
goto err;
if (!strcmp(option, "NDISC_NA_OP_TAR_LINK_ADDR")) {
if (mac_writer(op_ptr, value))
goto err;
op_ptr += 6;
}
else
goto err;
/* len in 8 octets unit */
op_len += tmp * 8;
}