sbin/rconfig/server.c

   1 /*
   2  * RCONFIG/SERVER.C
   3  *
   4  * $DragonFly: src/sbin/rconfig/server.c,v 1.1 2004/06/18 02:46:46 dillon Exp $
   5  */
   6
   7 #include "defs.h"
   8
   9 static void server_connection(int fd);
  10 static void service_packet_loop(int fd);
  11 static void server_chld_exit(int signo);
  12 static int nconnects;
  13
  14 void
  15 doServer(void)
  16 {
  17     tag_t tag;
  18
  19     /*
  20      * Listen on one or more UDP and TCP addresses, fork for each one.
  21      */
  22     signal(SIGCHLD, SIG_IGN);
  23     for (tag = AddrBase; tag; tag = tag->next) {
  24         struct sockaddr_in sain;
  25         char *host;
  26         int lfd;
  27         int fd;
  28         int on = 1;
  29
  30         bzero(&sain, sizeof(sain));
  31         if (tag->name == NULL) {
  32             sain.sin_addr.s_addr = INADDR_ANY;
  33             host = "<any>";
  34         } else {
  35             host = strdup(tag->name);
  36             if (inet_aton(host, &sain.sin_addr) == 0) {
  37                 struct hostent *hp;
  38                 if ((hp = gethostbyname2(host, AF_INET)) == NULL) {
  39                     fprintf(stderr, "Unable to resolve %s\n", host);
  40                     exit(1);
  41                 }
  42                 bcopy(hp->h_addr_list[0], &sain.sin_addr, hp->h_length);
  43                 free(host);
  44                 host = strdup(hp->h_name);
  45                 endhostent();
  46             }
  47         }
  48         sain.sin_port = htons(257);
  49         sain.sin_len = sizeof(sain);
  50         sain.sin_family = AF_INET;
  51         fflush(stdout);
  52         if (fork() == 0) {
  53             if ((lfd = socket(AF_INET, SOCK_STREAM, PF_UNSPEC)) < 0) {
  54                 fprintf(stderr, "%s: socket: %s\n", host, strerror(errno));
  55                 exit(1);
  56             }
  57             setsockopt(lfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
  58             if (bind(lfd, (void *)&sain, sizeof(sain)) < 0) {
  59                 fprintf(stderr, "%s: bind: %s\n", host, strerror(errno));
  60                 exit(1);
  61             }
  62             if (listen(lfd, 20) < 0) {
  63                 fprintf(stderr, "%s: listen: %s\n", host, strerror(errno));
  64                 exit(1);
  65             }
  66             signal(SIGCHLD, server_chld_exit);
  67             for (;;) {
  68                 int slen = sizeof(sain);
  69                 fd = accept(lfd, (void *)&sain, &slen);
  70                 if (fd < 0) {
  71                     if (errno != EINTR)
  72                         break;
  73                     continue;
  74                 }
  75                 ++nconnects; /* XXX sigblock/sigsetmask */
  76                 if (fork() == 0) {
  77                     close(lfd);
  78                     server_connection(fd);
  79                     exit(0);
  80                 }
  81                 close(fd);
  82             }
  83             exit(0);
  84         }
  85         if (fork() == 0) {
  86             if ((lfd = socket(AF_INET, SOCK_DGRAM, PF_UNSPEC)) < 0) {
  87                 fprintf(stderr, "%s: socket: %s\n", host, strerror(errno));
  88                 exit(1);
  89             }
  90             if (bind(lfd, (void *)&sain, sizeof(sain)) < 0) {
  91                 fprintf(stderr, "%s: bind: %s\n", host, strerror(errno));
  92                 exit(1);
  93             }
  94             service_packet_loop(lfd);
  95             exit(1);
  96         }
  97     }
  98     while (wait(NULL) > 0 || errno != EINTR)
  99         ;
 100 }
 101
 102 static
 103 void
 104 server_chld_exit(int signo)
 105 {
 106     while (wait3(NULL, WNOHANG, NULL) > 0)
 107         --nconnects;
 108 }
 109
 110 static
 111 void
 112 server_connection(int fd)
 113 {
 114     FILE *fi;
 115     FILE *fo;
 116     char buf[256];
 117     char *scan;
 118     const char *cmd;
 119     const char *name;
 120
 121     fi = fdopen(fd, "r");
 122     fo = fdopen(dup(fd), "w");
 123
 124     if (gethostname(buf, sizeof(buf)) == 0) {
 125         fprintf(fo, "108 HELLO SERVER=%s\r\n", buf);
 126     } else {
 127         fprintf(fo, "108 HELLO\r\n", buf);
 128     }
 129     fflush(fo);
 130
 131     while (fgets(buf, sizeof(buf), fi) != NULL) {
 132         scan = buf;
 133         cmd = parse_str(&scan, PAS_ALPHA);
 134         if (cmd == NULL) {
 135             fprintf(fo, "502 Illegal Command String\r\n");
 136         } else if (strcasecmp(cmd, "VAR") == 0) {
 137             fprintf(fo, "100 OK\r\n");
 138         } else if (strcasecmp(cmd, "TAG") == 0) {
 139             if ((name = parse_str(&scan, PAS_ALPHA|PAS_NUMERIC)) == NULL) {
 140                 fprintf(fo, "401 Illegal Tag\r\n");
 141             } else {
 142                 char *path = NULL;
 143                 FILE *fp;
 144                 asprintf(&path, "%s/%s.sh", TagDir, name);
 145                 if ((fp = fopen(path, "r")) == NULL) {
 146                     fprintf(fo, "402 '%s' Not Found\r\n", name);
 147                 } else {
 148                     long bytes;
 149                     int n;
 150                     int error = 0;
 151
 152                     fseek(fp, 0L, 2);
 153                     bytes = ftell(fp);
 154                     fseek(fp, 0L, 0);
 155                     fprintf(fo, "201 SIZE=%ld\r\n", bytes);
 156                     while (bytes > 0) {
 157                         n = (bytes > sizeof(buf)) ? sizeof(buf) : bytes;
 158                         n = fread(buf, 1, n, fp);
 159                         if (n <= 0) {
 160                             error = 1;
 161                             break;
 162                         }
 163                         if (fwrite(buf, 1, n, fo) != n) {
 164                             error = 1;
 165                             break;
 166                         }
 167                         bytes -= n;
 168                     }
 169                     fclose(fp);
 170                     if (bytes > 0 && ferror(fo) == 0) {
 171                         bzero(buf, sizeof(buf));
 172                         while (bytes > 0) {
 173                             n = (bytes > sizeof(buf)) ? sizeof(buf) : bytes;
 174                             if (fwrite(buf, 1, n, fo) != n)
 175                                 break;
 176                             bytes -= n;
 177                         }
 178                     }
 179                     fprintf(fo, "202 ERROR=%d\r\n", error);
 180                 }
 181                 free(path);
 182             }
 183         } else if (strcasecmp(cmd, "IDLE") == 0) {
 184             if ((name = parse_str(&scan, PAS_ANY)) == NULL) {
 185                 fprintf(fo, "401 Illegal String\r\n");
 186             } else {
 187                 fprintf(fo, "109 %s\r\n", name);
 188             }
 189         } else if (strcasecmp(cmd, "QUIT") == 0) {
 190             fprintf(fo, "409 Bye!\r\n");
 191             break;
 192         } else {
 193             fprintf(fo, "501 Unknown Command\r\n");
 194         }
 195         fflush(fo);
 196     }
 197     fclose(fi);
 198     fclose(fo);
 199 }
 200
 201 /*
 202  * UDP packet loop.  For now just handle one request per packet.  Note that
 203  * since the protocol is designed to be used in a broadcast environment,
 204  * we only respond when we have something to contribute.
 205  */
 206 static
 207 void
 208 service_packet_loop(int fd)
 209 {
 210     struct sockaddr_in sain;
 211     char ibuf[256+1];
 212     char obuf[256+1];
 213     int sain_len;
 214     int n;
 215     char *scan;
 216     const char *cmd;
 217     const char *name;
 218
 219     for (;;) {
 220         sain_len = sizeof(sain);
 221         n = recvfrom(fd, ibuf, sizeof(ibuf) - 1, 0, (void *)&sain, &sain_len);
 222         if (n < 0) {
 223             if (errno == EINTR)
 224                 continue;
 225             break;
 226         }
 227         ibuf[n] = 0;
 228         n = 0;
 229         scan = ibuf;
 230         cmd = parse_str(&scan, PAS_ALPHA);
 231         if (cmd == NULL) {
 232             ;
 233         } else if (strcasecmp(cmd, "TAG") == 0) {
 234             if ((name = parse_str(&scan, PAS_ALPHA|PAS_NUMERIC)) != NULL) {
 235                 char *path = NULL;
 236                 struct stat st;
 237                 asprintf(&path, "%s/%s.sh", TagDir, name);
 238                 if (stat(path, &st) == 0) {
 239                     snprintf(obuf, sizeof(obuf), "101 TAG=%s\r\n", name);
 240                     n = strlen(obuf);
 241                 }
 242                 free(path);
 243             }
 244         }
 245         if (n)
 246             sendto(fd, obuf, n, 0, (void *)&sain, sain_len);
 247     }
 248 }
 249