mdw@git.distorted.org.uk Git - adns/blob - src/internal.h

   1 /**/
   2
   3 #ifndef ADNS_INTERNAL_H_INCLUDED
   4 #define ADNS_INTERNAL_H_INCLUDED
   5
   6 #define PRINTFFORMAT(a,b) __attribute__((format(printf,a,b)))
   7 typedef unsigned char byte;
   8
   9 #include <stdarg.h>
  10 #include <assert.h>
  11 #include <unistd.h>
  12
  13 #include <sys/time.h>
  14
  15 #include "adns.h"
  16
  17 /* Configuration and constants */
  18
  19 #define MAXSERVERS 5
  20 #define UDPMAXRETRIES /*15*/5
  21 #define UDPRETRYMS 2000
  22 #define TCPMS 30000
  23 #define LOCALRESOURCEMS 20
  24
  25 #define DNS_UDPPORT 53
  26 #define DNS_MAXUDP 512
  27 #define DNS_MAXDOMAIN 255
  28 #define DNS_HDRSIZE 12
  29 #define DNS_CLASS_IN 1
  30
  31 /* Shared data structures */
  32
  33 typedef union {
  34   adns_status status;
  35   char *cp;
  36   adns_rrtype type;
  37   int i;
  38   struct in_addr ia;
  39   unsigned long ul;
  40 } rr_align;
  41
  42 typedef struct {
  43   int used, avail;
  44   byte *buf;
  45 } vbuf;
  46
  47 typedef union {
  48   void *ext;
  49   int dmaddr_index;
  50 } qcontext;
  51
  52 typedef struct {
  53   unsigned long searchkey; /* flags and typecode swapped */
  54   adns_rrtype type;
  55 } typeinfo;
  56
  57 struct adns__query {
  58   /* FIXME: make sure this is all init'd properly */
  59   enum { query_udp, query_tcpwait, query_tcpsent, query_child, query_done } state;
  60   adns_query back, next, parent;
  61   struct { adns_query head, tail; } children;
  62   struct { adns_query back, next; } siblings;
  63
  64   const typeinfo *typei;
  65   vbuf ans;
  66   int id, flags, udpretries;
  67   int udpnextserver;
  68   unsigned long udpsent, tcpfailed; /* bitmap indexed by server */
  69   struct timeval timeout;
  70   byte *querymsg;
  71   int querylen;
  72   qcontext context;
  73   char owner[1];
  74   /* After the owner name and nul comes the query message, pointed to by querymsg */
  75
  76   /* Possible states:
  77    *
  78    *  state   Queue   child  id   answer    nextudpserver  sentudp     failedtcp
  79    *
  80    *  udp     NONE    null   >=0  null      0              zero        zero
  81    *  udp     timew   null   >=0  null      any            nonzero     zero
  82    *  udp     NONE    null   >=0  null      any            nonzero     zero
  83    *
  84    *  tcpwait timew   null   >=0  null      irrelevant     zero        any
  85    *  tcpsent timew   null   >=0  null      irrelevant     zero        any
  86    *
  87    *  child   childw  set    >=0  partial   irrelevant     irrelevant  irrelevant
  88    *  done    output  null   -1   set/null  irrelevant     irrelevant  irrelevant
  89    *
  90    *                          +------------------------+
  91    *             START -----> |      udp/NONE          |
  92    *                          +------------------------+
  93    *                         /                       |\  \
  94    *        too big for UDP /             UDP timeout  \  \ send via UDP
  95    *        do this ASAP!  /              more retries  \  \   do this ASAP!
  96    *                     |_                  desired     \  _|
  97    *              +---------------+                     +-----------+
  98    *              | tcpwait/timew | ____                | udp/timew |
  99    *              +---------------+     \               +-----------+
 100    *                    |  ^             |                 | |
 101    *     TCP conn'd;    |  | TCP died    |                 | |
 102    *     send via TCP   |  | more        |     UDP timeout | |
 103    *     do this ASAP!  |  | servers     |      no more    | |
 104    *                    v  | to try      |      retries    | |
 105    *              +---------------+      |      desired    | |
 106    *              | tcpsent/timew | ____ |                 | |
 107    *              +---------------+     \|                 | |
 108    *                  \   \ TCP died     | TCP             | |
 109    *                   \   \ no more     | timeout         / |
 110    *                    \   \ servers    |                /  |
 111    *                     \   \ to try    |               /   |
 112    *                  got \   \          v             |_    / got
 113    *                 reply \   _| +------------------+      / reply
 114    *                        \     | done/output FAIL |     /
 115    *                         \    +------------------+    /
 116    *                          \                          /
 117    *                           _|                      |_
 118    *                             (..... got reply ....)
 119    *                              /                   \
 120    *        need child query/ies /                     \ no child query
 121    *                            /                       \
 122    *                          |_                         _|
 123    *                +--------------+                   +----------------+
 124    *                | child/childw | ----------------> | done/output OK |
 125    *                +--------------+  children done    +----------------+
 126    */
 127 };
 128
 129 struct adns__state {
 130   adns_initflags iflags;
 131   FILE *diagfile;
 132   struct { adns_query head, tail; } timew, childw, output;
 133   int nextid, udpsocket, tcpsocket;
 134   vbuf rqbuf, tcpsend, tcprecv;
 135   int nservers, tcpserver;
 136   enum adns__tcpstate { server_disconnected, server_connecting, server_ok } tcpstate;
 137   struct timeval tcptimeout;
 138   struct server {
 139     struct in_addr addr;
 140   } servers[MAXSERVERS];
 141 };
 142
 143 /* From setup.c: */
 144
 145 void adns__vdiag(adns_state ads, const char *pfx, adns_initflags prevent,
 146                  int serv, const char *fmt, va_list al);
 147 void adns__debug(adns_state ads, int serv, const char *fmt, ...) PRINTFFORMAT(3,4);
 148 void adns__warn(adns_state ads, int serv, const char *fmt, ...) PRINTFFORMAT(3,4);
 149 void adns__diag(adns_state ads, int serv, const char *fmt, ...) PRINTFFORMAT(3,4);
 150
 151 int adns__vbuf_ensure(vbuf *vb, int want);
 152 int adns__vbuf_append(vbuf *vb, const byte *data, int len);
 153 /* 1=>success, 0=>realloc failed */
 154 void adns__vbuf_appendq(vbuf *vb, const byte *data, int len);
 155 void adns__vbuf_init(vbuf *vb);
 156
 157 int adns__setnonblock(adns_state ads, int fd); /* => errno value */
 158
 159 /* From submit.c: */
 160
 161 void adns__query_nomem(adns_state ads, adns_query qu);
 162 void adns__query_fail(adns_state ads, adns_query qu, adns_status stat);
 163
 164 /* From query.c: */
 165
 166 void adns__query_udp(adns_state ads, adns_query qu, struct timeval now);
 167 void adns__query_tcp(adns_state ads, adns_query qu, struct timeval now);
 168 adns_status adns__mkquery(adns_state ads, const char *owner, int ol, int id,
 169                           adns_rrtype type, adns_queryflags flags);
 170
 171 /* From reply.c: */
 172
 173 void adns__procdgram(adns_state ads, const byte *dgram, int len, int serv);
 174
 175 /* From event.c: */
 176
 177 void adns__tcp_broken(adns_state ads, const char *what, const char *why);
 178 void adns__tcp_tryconnect(adns_state ads, struct timeval now);
 179 void adns__autosys(adns_state ads, struct timeval now);
 180
 181 /* Useful static inline functions: */
 182
 183 static inline void timevaladd(struct timeval *tv_io, long ms) {
 184   struct timeval tmp;
 185   assert(ms>=0);
 186   tmp= *tv_io;
 187   tmp.tv_usec += (ms%1000)*1000000;
 188   tmp.tv_sec += ms/1000;
 189   if (tmp.tv_usec >= 1000000) { tmp.tv_sec++; tmp.tv_usec -= 1000; }
 190   *tv_io= tmp;
 191 }
 192
 193 static inline int ctype_whitespace(int c) { return c==' ' || c=='\n' || c=='\t'; }
 194 static inline int ctype_digit(int c) { return c>='0' && c<='9'; }
 195
 196 /* Useful macros */
 197
 198 #define LIST_INIT(list) ((list).head= (list).tail= 0)
 199
 200 #define LIST_UNLINK_PART(list,node,part) \
 201   do { \
 202     if ((node)->back) (node)->back->part next= (node)->part next; \
 203       else                        (list).head= (node)->part next; \
 204     if ((node)->next) (node)->next->part back= (node)->part back; \
 205       else                        (list).tail= (node)->part back; \
 206   } while(0)
 207
 208 #define LIST_LINK_TAIL_PART(list,node,part) \
 209   do { \
 210     (node)->part back= 0; \
 211     (node)->part next= (list).tail; \
 212     if ((list).tail) (list).tail->part back= (node); else (list).part head= (node); \
 213     (list).tail= (node); \
 214   } while(0)
 215
 216 #define LIST_UNLINK(list,node) LIST_UNLINK_PART(list,node,)
 217 #define LIST_LINK_TAIL(list,node) LIST_LINK_TAIL_PART(list,node,)
 218
 219 #endif