glibc-getaddrinfo-workaround.patch

   1 #! /bin/sh -e
   2
   3 # DP: Hack for some ordering in getaddrinfo lookups
   4
   5 if [ $# -ne 2 ]; then
   6     echo >&2 "`basename $0`: script expects -patch|-unpatch as argument"
   7     exit 1
   8 fi
   9 case "$1" in
  10     -patch) patch -d "$2" -f --no-backup-if-mismatch -p1 < $0;;
  11     -unpatch) patch -d "$2" -f --no-backup-if-mismatch -R -p1 < $0;;
  12     *)
  13         echo >&2 "`basename $0`: script expects -patch|-unpatch as argument"
  14         exit 1
  15 esac
  16 exit 0
  17
  18 --- glibc/sysdeps/posix/getaddrinfo.c~  2000/11/18 08:30:02     1.34
  19 +++ glibc/sysdeps/posix/getaddrinfo.c   2001/01/09 01:46:49
  20 @@ -264,7 +264,7 @@
  21    return 0;
  22  }
  23
  24 -#define gethosts(_family, _type)                               \
  25 +#define gethosts(_family, _type, _name)                                \
  26   {                                                             \
  27    int i, herrno;                                               \
  28    size_t tmpbuflen;                                            \
  29 @@ -275,11 +275,12 @@
  30    do {                                                         \
  31      tmpbuflen *= 2;                                            \
  32      tmpbuf = extend_alloca (tmpbuf, tmpbuflen, 2 * tmpbuflen); \
  33 -    rc = __gethostbyname2_r (name, _family, &th, tmpbuf,       \
  34 +    rc = __gethostbyname2_r (_name, _family, &th, tmpbuf,      \
  35           tmpbuflen, &h, &herrno);                              \
  36    } while (rc == ERANGE && herrno == NETDB_INTERNAL);          \
  37    if (rc != 0)                                                 \
  38      {                                                          \
  39 +      succeeded--;                                             \
  40        if (herrno == NETDB_INTERNAL)                            \
  41         {                                                       \
  42           __set_h_errno (herrno);                               \
  43 @@ -307,6 +308,26 @@
  44      }                                                          \
  45   }
  46
  47 +/* If we are looking for both IPv4 and IPv6 address we don't
  48 +   want the lookup functions to automatically promote IPv4
  49 +   addresses to IPv6 addresses.  Currently this is decided
  50 +   by setting the RES_USE_INET6 bit in _res.options.  */
  51 +#define tryname(__name)                                                \
  52 +  {                                                            \
  53 +    succeeded = req->ai_family == AF_UNSPEC ? 2 : 1;           \
  54 +    if (req->ai_family == AF_UNSPEC)                           \
  55 +      _res.options &= ~RES_USE_INET6;                          \
  56 +    if (req->ai_family == AF_UNSPEC ||                         \
  57 +       req->ai_family == AF_INET6)                             \
  58 +      gethosts (AF_INET6, struct in6_addr, __name);            \
  59 +    no_inet6_data = no_data;                                   \
  60 +    if (req->ai_family == AF_UNSPEC)                           \
  61 +      _res.options = old_res_options;                          \
  62 +    if (req->ai_family == AF_UNSPEC ||                         \
  63 +       req->ai_family == AF_INET)                              \
  64 +    gethosts (AF_INET, struct in_addr, __name);                        \
  65 +  }
  66 +
  67  static int
  68  gaih_inet (const char *name, const struct gaih_service *service,
  69            const struct addrinfo *req, struct addrinfo **pai)
  70 @@ -316,6 +337,10 @@
  71    struct gaih_addrtuple *at = NULL;
  72    int rc;
  73
  74 +  /* Make sure we are initialized now */
  75 +  if (!(_res.options & RES_INIT))
  76 +    res_ninit(&_res);
  77 +
  78    if (req->ai_protocol || req->ai_socktype)
  79      {
  80        ++tp;
  81 @@ -489,34 +514,47 @@
  82           struct gaih_addrtuple **pat = &at;
  83           int no_data = 0;
  84           int no_inet6_data;
  85 +         int succeeded = -1;
  86           int old_res_options = _res.options;
  87
  88 -         /* If we are looking for both IPv4 and IPv6 address we don't
  89 -            want the lookup functions to automatically promote IPv4
  90 -            addresses to IPv6 addresses.  Currently this is decided
  91 -            by setting the RES_USE_INET6 bit in _res.options.  */
  92 -         if (req->ai_family == AF_UNSPEC)
  93 -           _res.options &= ~RES_USE_INET6;
  94 -
  95 -         if (req->ai_family == AF_UNSPEC || req->ai_family == AF_INET6)
  96 -           gethosts (AF_INET6, struct in6_addr);
  97 -         no_inet6_data = no_data;
  98 +         /* If we have a dotted name, first try an absolute lookup.  This
  99 +            avoids problem where the resolver will try to search domains
 100 +            even though we may have a fqdn, which is bad since ipv6 lookups
 101 +            are performed first.  */
 102 +         if (strchr(name, '.') != NULL)
 103 +           {
 104 +             int namelen = strlen(name);
 105 +             char *newname = __alloca(namelen + 2);
 106
 107 -         if (req->ai_family == AF_UNSPEC)
 108 -           _res.options = old_res_options;
 109 +             strcpy(newname, name);
 110 +             newname[namelen] = '.';
 111 +             newname[namelen+1] = '\0';
 112
 113 -         if (req->ai_family == AF_UNSPEC || req->ai_family == AF_INET)
 114 -           gethosts (AF_INET, struct in_addr);
 115 +             tryname(newname);
 116 +           }
 117
 118 -         if (no_data != 0 && no_inet6_data != 0)
 119 +         /* If the previous didn't work, or we don't have a dotted name,
 120 +            we try again like normal, letting the resolver manage domain
 121 +            searching.  */
 122 +         if (succeeded <= 0)
 123             {
 124 -             /* If both requests timed out report this.  */
 125 -             if (no_data == EAI_AGAIN && no_inet6_data == EAI_AGAIN)
 126 -               return -EAI_AGAIN;
 127 -
 128 -             /* We made requests but they turned out no data.  The name
 129 -                is known, though.  */
 130 -             return (GAIH_OKIFUNSPEC | -EAI_NODATA);
 131 +             _res.options = old_res_options;
 132 +
 133 +             if (succeeded == 0) /* we've tried absolute, now try searches */
 134 +               _res.ndots = 99;
 135 +
 136 +             tryname(name);
 137 +
 138 +             if (no_data != 0 && no_inet6_data != 0)
 139 +               {
 140 +                 /* If both requests timed out report this.  */
 141 +                 if (no_data == EAI_AGAIN && no_inet6_data == EAI_AGAIN)
 142 +                   return -EAI_AGAIN;
 143 +
 144 +                 /* We made requests but they turned out no data.  The name
 145 +                    is known, though.  */
 146 +                 return (GAIH_OKIFUNSPEC | -EAI_NODATA);
 147 +               }
 148             }
 149         }
 150