rtk处理ra报文流程

#include <stdio.h> #include <stdlib.h> #include <string.h> #include <signal.h> #include <unistd.h> #include <sys/ioctl.h> #define __USE_GNU /* luna_g3 need this macro to define struct in6_pktinfo in linux/in.h */ #include <arpa/inet.h> #include <sys/types.h> #include <sys/socket.h> #include <sys/un.h> //#include <net/if.h> /* this may cause redefined error with <linux/if.h> in some tool chain. */ #include <linux/netlink.h> #include <linux/rtnetlink.h> #include <linux/sockios.h> #include <netinet/ip6.h> #include <netinet/icmp6.h> #include <sys/epoll.h> #include <fcntl.h> #include <config/autoconf.h> #include <linux/autoconf.h> #include <errno.h> #include <linux/if.h> #include <rtk/utility.h> #include <rtk/mib.h> #define MAX_RDNSS_NUM 3 #define MAX_DNS_STRING_LEN 128 #if 0 /* Avoid to redefined the struct in6_pktinfo in linux/ipv6.h */ #ifndef __USE_GNU /* from linux/in.h*/ struct in6_pktinfo { struct in6_addr ipi6_addr; /* src/dst IPv6 address */ unsigned int ipi6_ifindex; /* send/recv interface index */ }; #endif #endif #ifndef IFNAMSIZ #define IFNAMSIZ 16 #endif #ifndef ND_OPT_RDNSS #define ND_OPT_RDNSS 25 #endif #ifndef ND_OPT_MTU #define ND_OPT_MTU 5 #endif #ifndef ND_OPT_DNSSL #define ND_OPT_DNSSL 31 #endif #define DEBUG_INFO(fmt,arg...) do{if(debug_flag==0)break;fprintf(stderr,"[ramonitor]%s@%d>>> ",__func__,__LINE__);fprintf(stderr,fmt,##arg);}while(0) #define DEBUG_ERROR(fmt,arg...) do{fprintf(stderr,"ERROR! [ramonitor]%s@%d>>> ",__func__,__LINE__);fprintf(stderr,fmt,##arg);}while(0) #define RA_INFO_FILE "/var/rainfo_" #define SYSTEMD_PIDFILE "/var/run/systemd.pid" #define PID_FILE "/var/run/ramonitor.pid" /* #define RA_INFO_FILE "/var/dhcp6_info.conf" */ #define MAX_WAN_DEV_NUM 8 /* Now we only support 8 WAN. */ #define EPOLL_MAXEVENTS 1 /* This struct can be used for other ND Option */ struct nd_opt_rdnss { uint8_t nd_opt_rdnss_type; uint8_t nd_opt_rdnss_len; uint16_t nd_opt_rdnss_resserved1; uint32_t nd_opt_rdnss_lifetime; /* followed by one or more IPv6 addresses */ }; struct nd_opt_mtu_t { uint8_t nd_opt_type; uint8_t nd_opt_len; uint16_t nd_opt_resserved1; uint32_t nd_opt_mtu_data; /* followed by one or more IPv6 addresses */ }; struct ra_conf{ uint8_t valid; uint32_t ifindex; uint8_t if_name[IFNAMSIZ]; struct in6_addr srcip; /* src ip of RA packet */ /* Maybe in the future, we need to support multi_prefix. We can use prefix[MAX_PREFIX_NUM] or struct in6_addr prefix2 ... */ struct in6_addr prefix; /* prefix of icmpv6 option(Prefix information) */ uint8_t prefix_len; uint8_t prefix_onlink; uint32_t prefix_validtime; uint32_t prefix_preferredtime; uint8_t M; /* M flag of RA packet */ uint8_t O; /* O flag of RA packet */ uint16_t lifetime; uint8_t rdnss[MAX_RDNSS_NUM][INET6_ADDRSTRLEN]; /* Now we only support 3 RDNSS. */ uint16_t rdnss_lifetime[MAX_RDNSS_NUM]; /* Now we only support 3 RDNSS. */ uint32_t mtu; uint8_t dnssl[MAX_DNS_STRING_LEN]; uint16_t dnssl_lifetime; }; struct link_status_entry{ char ifname[IFNAMSIZ]; struct ifinfomsg ifi; struct link_status_entry *next; }; struct link_status_entry *link_head=NULL; struct ra_conf wan_ra_conf[MAX_WAN_DEV_NUM]; struct epoll_event* events_list = NULL; int efd = 0; int sock_nl = -1; /* netlink sock to receive intf create/delete/up/down events */ int sock_icmpv6 = 0; int debug_flag = 0; static void log_pid(void); static int init_netlink_socket(void); static int init_socket(void); static int init_epoll(void); int parse_rdnss(const struct nd_opt_hdr *opt_hdr, struct ra_conf *conf, const char *ifname); int parse_dnssl(const struct nd_opt_hdr *opt_hdr, struct ra_conf *conf, const char *ifname); int parse_mtu(const struct nd_opt_hdr *opt_hdr, struct ra_conf *conf, const char *ifname); static void init_ra_conf(void); static int indextoname(int fd, int index, char *name); static int get_wan_ifindex(struct msghdr * msgptr, struct ra_conf * conf); static int parse_ra(char* buf, int datalen, struct ra_conf * conf); static void dump_ra_conf(struct ra_conf * conf); static int check_conf(struct ra_conf * conf); static int compare_rdnss(struct ra_conf *conf1, struct ra_conf *conf2); static void save_ra_conf(struct ra_conf * conf); static void delete_ra_conf(const char *intf); static int nl_handler(int sock); static void process_icmpv6_packet(char* buf, int datalen, char* in_dev, const void * srcIp6, struct msghdr * msgptr); static void do_epoll(void); void exit_clean(void); static void sig_handler(int signum); static void log_pid(void) { FILE *f; pid_t pid; pid = getpid(); if((f = fopen(PID_FILE, "w")) == NULL) return; fprintf(f, "%d\n", pid); fclose(f); } void deleteLinkEntry(struct link_status_entry **head, const char *ifname){ struct link_status_entry *curr=NULL, *parent=NULL; unsigned char len=0; if(!ifname){ DEBUG_ERROR("null parameters\n"); return; } /* search entry */ curr = *head; while(curr){ len = (strlen(curr->ifname)>strlen(ifname))?strlen(curr->ifname):strlen(ifname); if(!strncmp(curr->ifname, ifname, len)){ if(parent){ parent->next = curr->next; free(curr); }else{ /* first entry */ *head = curr->next; free(curr); } DEBUG_INFO("free %s\n", ifname); break; } parent = curr; curr = curr->next; } return; } struct link_status_entry *updateLinkEntry(struct link_status_entry **head, const char *ifname, struct ifinfomsg *ifi){ struct link_status_entry *curr=NULL; unsigned int currFlags=0; unsigned char len=0; if(!ifname | !ifi){ DEBUG_ERROR("null parameters\n"); return NULL; } /* netlink event should not realtime status, it has timing delay, * So, update flags to reduce some unnecessary processing */ if (getInFlags( ifname, &currFlags) == 0){ DEBUG_ERROR("get %s current interface flags fail\n", ifname); return NULL; } if(currFlags != ifi->ifi_flags){ DEBUG_INFO("[%s] update flags from 0x%x to 0x%x\n", __FUNCTION__, ifi->ifi_flags, currFlags); ifi->ifi_flags = currFlags; } /* search entry */ curr = *head; while(curr){ len = (strlen(curr->ifname)>strlen(ifname))?strlen(curr->ifname):strlen(ifname); if(!strncmp(curr->ifname, ifname, len)){ /* Extry exist, copy and update change mask */ ifi->ifi_change = curr->ifi.ifi_flags ^ ifi->ifi_flags; memcpy(&curr->ifi, ifi, sizeof(curr->ifi)); return curr; } curr = curr->next; } /* entry not exist, new it */ curr = (struct link_status_entry *)calloc(1, sizeof(struct link_status_entry)); if(!curr){ DEBUG_ERROR("allocate memory fail\n"); return NULL; } strncpy(curr->ifname, ifname, sizeof(curr->ifname)); // exclusive or with 0x0 to get what flag it set ifi->ifi_change = ifi->ifi_flags ^ 0x0; memcpy(&curr->ifi, ifi, sizeof(curr->ifi)); curr->next = NULL; if(!*head){ *head = curr; }else{ curr->next = *head; *head = curr; } return curr; } static int init_netlink_socket(void) { struct sockaddr_nl sa; if ((sock_nl = socket(PF_NETLINK, SOCK_RAW, NETLINK_ROUTE)) == -1) { DEBUG_ERROR("%d:%s", errno, strerror(errno)); return -1; } memset (&sa,0,sizeof(sa)); sa.nl_family = AF_NETLINK; sa.nl_pad = 0; sa.nl_pid = getpid(); /* monitor network interface create/delete/up/down events */ sa.nl_groups = RTMGRP_LINK; if (bind(sock_nl, (struct sockaddr *)&sa, sizeof(sa)) == -1) { DEBUG_ERROR("%d:%s", errno, strerror(errno)); close(sock_nl); return -1; } return 0; } static int init_socket(void) { struct sockaddr_in6 addr; struct icmp6_filter filterv6; int flags; int opt = 1; int err; if ((sock_icmpv6 = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) { DEBUG_ERROR("Create icmpv6 socket fail!\n"); return -1; } #if defined IPV6_PKTINFO && !defined IPV6_RECVPKTINFO #define IPV6_RECVPKTINFO IPV6_PKTINFO #endif /* See RFC 3542 */ err = setsockopt(sock_icmpv6, IPPROTO_IPV6, IPV6_RECVPKTINFO, (int[]){1}, sizeof(int)); if(err) DEBUG_ERROR("%d:%s", errno, strerror(errno)); ICMP6_FILTER_SETBLOCKALL(&filterv6); ICMP6_FILTER_SETPASS