nsz Git - musl/blob - src/network/lookup_serv.c

   1 #include <sys/socket.h>
   2 #include <netinet/in.h>
   3 #include <netdb.h>
   4 #include <ctype.h>
   5 #include <string.h>
   6 #include <fcntl.h>
   7 #include <errno.h>
   8 #include "lookup.h"
   9 #include "stdio_impl.h"
  10
  11 int __lookup_serv(struct service buf[static MAXSERVS], const char *name, int proto, int socktype, int flags)
  12 {
  13         char line[128];
  14         int cnt = 0;
  15         char *p, *z = "";
  16         unsigned long port = 0;
  17
  18         switch (socktype) {
  19         case SOCK_STREAM:
  20                 switch (proto) {
  21                 case 0:
  22                         proto = IPPROTO_TCP;
  23                 case IPPROTO_TCP:
  24                         break;
  25                 default:
  26                         return EAI_SERVICE;
  27                 }
  28                 break;
  29         case SOCK_DGRAM:
  30                 switch (proto) {
  31                 case 0:
  32                         proto = IPPROTO_UDP;
  33                 case IPPROTO_UDP:
  34                         break;
  35                 default:
  36                         return EAI_SERVICE;
  37                 }
  38         case 0:
  39                 break;
  40         default:
  41                 if (name) return EAI_SERVICE;
  42                 buf[0].port = 0;
  43                 buf[0].proto = proto;
  44                 buf[0].socktype = socktype;
  45                 return 1;
  46         }
  47
  48         if (name) {
  49                 if (!*name) return EAI_SERVICE;
  50                 port = strtoul(name, &z, 10);
  51         }
  52         if (!*z) {
  53                 if (port > 65535) return EAI_SERVICE;
  54                 if (proto != IPPROTO_UDP) {
  55                         buf[cnt].port = port;
  56                         buf[cnt].socktype = SOCK_STREAM;
  57                         buf[cnt++].proto = IPPROTO_TCP;
  58                 }
  59                 if (proto != IPPROTO_TCP) {
  60                         buf[cnt].port = port;
  61                         buf[cnt].socktype = SOCK_DGRAM;
  62                         buf[cnt++].proto = IPPROTO_UDP;
  63                 }
  64                 return cnt;
  65         }
  66
  67         if (flags & AI_NUMERICSERV) return EAI_SERVICE;
  68
  69         size_t l = strlen(name);
  70
  71         unsigned char _buf[1032];
  72         FILE _f, *f = __fopen_rb_ca("/etc/services", &_f, _buf, sizeof _buf);
  73         if (!f) switch (errno) {
  74         case ENOENT:
  75         case ENOTDIR:
  76         case EACCES:
  77                 return EAI_SERVICE;
  78         default:
  79                 return EAI_SYSTEM;
  80         }
  81
  82         while (fgets(line, sizeof line, f) && cnt < MAXSERVS) {
  83                 if ((p=strchr(line, '#'))) *p++='\n', *p=0;
  84
  85                 /* Find service name */
  86                 for(p=line; (p=strstr(p, name)); p++) {
  87                         if (p>line && !isspace(p[-1])) continue;
  88                         if (p[l] && !isspace(p[l])) continue;
  89                         break;
  90                 }
  91                 if (!p) continue;
  92
  93                 /* Skip past canonical name at beginning of line */
  94                 for (p=line; *p && !isspace(*p); p++);
  95
  96                 port = strtoul(p, &z, 10);
  97                 if (port > 65535 || z==p) continue;
  98                 if (!strncmp(z, "/udp", 4)) {
  99                         if (proto == IPPROTO_TCP) continue;
 100                         buf[cnt].port = port;
 101                         buf[cnt].socktype = SOCK_DGRAM;
 102                         buf[cnt++].proto = IPPROTO_UDP;
 103                 }
 104                 if (!strncmp(z, "/tcp", 4)) {
 105                         if (proto == IPPROTO_UDP) continue;
 106                         buf[cnt].port = port;
 107                         buf[cnt].socktype = SOCK_STREAM;
 108                         buf[cnt++].proto = IPPROTO_TCP;
 109                 }
 110         }
 111         __fclose_ca(f);
 112         return cnt > 0 ? cnt : EAI_SERVICE;
 113 }