util.c

   1 /* Misc util functions */
   2
   3 #include <unistd.h>
   4 #include <errno.h>
   5 #include <sched.h>
   6 #include <sys/socket.h>
   7 #include <netinet/in.h>
   8 #include <arpa/inet.h>
   9 #include <string.h>
  10 #include <sys/mman.h>
  11
  12 #include "l2tpns.h"
  13 #ifdef BGP
  14 #include "bgp.h"
  15 #endif
  16
  17 // format ipv4 addr as a dotted-quad; n chooses one of 4 static buffers
  18 // to use
  19 char *fmtaddr(in_addr_t addr, int n)
  20 {
  21     static char addrs[4][16];
  22     struct in_addr in;
  23
  24     if (n < 0 || n >= 4)
  25         return "";
  26
  27     in.s_addr = addr;
  28     return strcpy(addrs[n], inet_ntoa(in));
  29 }
  30
  31 void *shared_malloc(unsigned int size)
  32 {
  33     void * p;
  34     p = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
  35
  36     if (p == MAP_FAILED)
  37         p = NULL;
  38
  39     return p;
  40 }
  41
  42 extern int forked;
  43 extern int cluster_sockfd, tunfd, udpfd, controlfd, daefd, snoopfd, ifrfd, ifr6fd, rand_fd;
  44 extern int *radfds;
  45
  46 pid_t fork_and_close()
  47 {
  48     pid_t pid = fork();
  49     int i;
  50
  51     if (pid)
  52         return pid;
  53
  54     forked++;
  55     if (config->scheduler_fifo)
  56     {
  57         struct sched_param params = {0};
  58         params.sched_priority = 0;
  59         if (sched_setscheduler(0, SCHED_OTHER, &params))
  60         {
  61             LOG(0, 0, 0, "Error setting scheduler to OTHER after fork: %s\n", strerror(errno));
  62             LOG(0, 0, 0, "This is probably really really bad.\n");
  63         }
  64     }
  65
  66     signal(SIGPIPE, SIG_DFL);
  67     signal(SIGCHLD, SIG_DFL);
  68     signal(SIGHUP,  SIG_DFL);
  69     signal(SIGUSR1, SIG_DFL);
  70     signal(SIGQUIT, SIG_DFL);
  71     signal(SIGKILL, SIG_DFL);
  72     signal(SIGTERM, SIG_DFL);
  73
  74     // Close sockets
  75     if (clifd != -1)          close(clifd);
  76     if (cluster_sockfd != -1) close(cluster_sockfd);
  77     if (tunfd != -1)          close(tunfd);
  78     if (udpfd != -1)          close(udpfd);
  79     if (controlfd != -1)      close(controlfd);
  80     if (daefd != -1)          close(daefd);
  81     if (snoopfd != -1)        close(snoopfd);
  82     if (rand_fd != -1)        close(rand_fd);
  83     if (epollfd != -1)        close(epollfd);
  84
  85     for (i = 0; radfds && i < RADIUS_FDS; i++)
  86         close(radfds[i]);
  87
  88 #ifdef BGP
  89     for (i = 0; i < BGP_NUM_PEERS; i++)
  90         if (bgp_peers[i].sock != -1)
  91             close(bgp_peers[i].sock);
  92 #endif /* BGP */
  93
  94     return pid;
  95 }
  96
  97 ssize_t recvfromto(int s, void *buf, size_t len, int flags,
  98     struct sockaddr *from, socklen_t *fromlen, struct in_addr *toaddr)
  99 {
 100     ssize_t r;
 101     struct msghdr msg;
 102     struct cmsghdr *cmsg;
 103     struct iovec vec;
 104     char cbuf[128];
 105
 106     memset(&msg, 0, sizeof(msg));
 107     msg.msg_name = from;
 108     msg.msg_namelen = *fromlen;
 109
 110     vec.iov_base = buf;
 111     vec.iov_len = len;
 112     msg.msg_iov = &vec;
 113     msg.msg_iovlen = 1;
 114     msg.msg_flags = 0;
 115
 116     msg.msg_control = cbuf;
 117     msg.msg_controllen = sizeof(cbuf);
 118
 119     if ((r = recvmsg(s, &msg, flags)) < 0)
 120         return r;
 121
 122     if (fromlen)
 123         *fromlen = msg.msg_namelen;
 124
 125     memset(toaddr, 0, sizeof(*toaddr));
 126     for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg))
 127     {
 128         if (cmsg->cmsg_level == SOL_IP && cmsg->cmsg_type == IP_PKTINFO)
 129         {
 130             struct in_pktinfo *i = (struct in_pktinfo *) CMSG_DATA(cmsg);
 131             memcpy(toaddr, &i->ipi_addr, sizeof(*toaddr));
 132             break;
 133         }
 134     }
 135
 136     return r;
 137 }
 138
 139 ssize_t sendtofrom(int s, void const *buf, size_t len, int flags,
 140     struct sockaddr const *to, socklen_t tolen, struct in_addr const *from)
 141 {
 142     struct msghdr msg;
 143     struct cmsghdr *cmsg;
 144     struct iovec vec;
 145     struct in_pktinfo pktinfo;
 146     char cbuf[CMSG_SPACE(sizeof(pktinfo))];
 147
 148     memset(&msg, 0, sizeof(msg));
 149     msg.msg_name = (struct sockaddr *) to;
 150     msg.msg_namelen = tolen;
 151
 152     vec.iov_base = (void *) buf;
 153     vec.iov_len = len;
 154     msg.msg_iov = &vec;
 155     msg.msg_iovlen = 1;
 156     msg.msg_flags = 0;
 157
 158     msg.msg_control = cbuf;
 159     msg.msg_controllen = sizeof(cbuf);
 160
 161     cmsg = CMSG_FIRSTHDR(&msg);
 162     cmsg->cmsg_level = SOL_IP;
 163     cmsg->cmsg_type = IP_PKTINFO;
 164     cmsg->cmsg_len = CMSG_LEN(sizeof(pktinfo));
 165
 166     memset(&pktinfo, 0, sizeof(pktinfo));
 167     memcpy(&pktinfo.ipi_spec_dst, from, sizeof(*from));
 168     memcpy(CMSG_DATA(cmsg), &pktinfo, sizeof(pktinfo));
 169
 170     return sendmsg(s, &msg, flags);
 171 }