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_PORT 53
  26 #define DNS_MAXUDP 512
  27 #define DNS_MAXDOMAIN 255
  28 #define DNS_HDRSIZE 12
  29 #define DNS_CLASS_IN 1
  30
  31 typedef enum {
  32   rcode_noerror,
  33   rcode_formaterror,
  34   rcode_servfail,
  35   rcode_nxdomain,
  36   rcode_notimp,
  37   rcode_refused
  38 } dns_rcode;
  39
  40 /* Shared data structures */
  41
  42 typedef union {
  43   adns_status status;
  44   char *cp;
  45   adns_rrtype type;
  46   int i;
  47   struct in_addr ia;
  48   unsigned long ul;
  49 } rr_align;
  50
  51 typedef struct {
  52   int used, avail;
  53   byte *buf;
  54 } vbuf;
  55
  56 typedef union {
  57   void *ext;
  58   int dmaddr_index;
  59 } qcontext;
  60
  61 typedef struct {
  62   adns_rrtype type;
  63   int rrsz;
  64   adns_status (*get_fn)(adns_state ads, adns_query qu, int serv,
  65                         const byte *dgram, int dglen,
  66                         int *cbyte_io, int max,
  67                         int nsstart, int arcount, int *arstart_io,
  68                         int roff, int *rcount_io);
  69 } typeinfo;
  70
  71 struct adns__query {
  72   /* FIXME: make sure this is all init'd properly */
  73   enum { query_udp, query_tcpwait, query_tcpsent, query_child, query_done } state;
  74   adns_query back, next, parent;
  75   struct { adns_query head, tail; } children;
  76   struct { adns_query back, next; } siblings;
  77
  78   const typeinfo *typei;
  79   vbuf ans;
  80   int id, flags, udpretries;
  81   int udpnextserver;
  82   unsigned long udpsent, tcpfailed; /* bitmap indexed by server */
  83   struct timeval timeout;
  84   byte *querymsg;
  85   int querylen, cnameoff, rrsoff;
  86   qcontext context;
  87   char owner[1];
  88   /* After the owner name and nul comes the query message, pointed to by querymsg */
  89
  90   /* Possible states:
  91    *
  92    *  state   Queue   child  id   answer    nextudpserver  sentudp     failedtcp
  93    *
  94    *  udp     NONE    null   >=0  null      0              zero        zero
  95    *  udp     timew   null   >=0  null      any            nonzero     zero
  96    *  udp     NONE    null   >=0  null      any            nonzero     zero
  97    *
  98    *  tcpwait timew   null   >=0  null      irrelevant     zero        any
  99    *  tcpsent timew   null   >=0  null      irrelevant     zero        any
 100    *
 101    *  child   childw  set    >=0  partial   irrelevant     irrelevant  irrelevant
 102    *  done    output  null   -1   set/null  irrelevant     irrelevant  irrelevant
 103    *
 104    *                          +------------------------+
 105    *             START -----> |      udp/NONE          |
 106    *                          +------------------------+
 107    *                         /                       |\  \
 108    *        too big for UDP /             UDP timeout  \  \ send via UDP
 109    *        do this ASAP!  /              more retries  \  \   do this ASAP!
 110    *                     |_                  desired     \  _|
 111    *              +---------------+                     +-----------+
 112    *              | tcpwait/timew | ____                | udp/timew |
 113    *              +---------------+     \               +-----------+
 114    *                    |  ^             |                 | |
 115    *     TCP conn'd;    |  | TCP died    |                 | |
 116    *     send via TCP   |  | more        |     UDP timeout | |
 117    *     do this ASAP!  |  | servers     |      no more    | |
 118    *                    v  | to try      |      retries    | |
 119    *              +---------------+      |      desired    | |
 120    *              | tcpsent/timew | ____ |                 | |
 121    *              +---------------+     \|                 | |
 122    *                  \   \ TCP died     | TCP             | |
 123    *                   \   \ no more     | timeout         / |
 124    *                    \   \ servers    |                /  |
 125    *                     \   \ to try    |               /   |
 126    *                  got \   \          v             |_    / got
 127    *                 reply \   _| +------------------+      / reply
 128    *                        \     | done/output FAIL |     /
 129    *                         \    +------------------+    /
 130    *                          \                          /
 131    *                           _|                      |_
 132    *                             (..... got reply ....)
 133    *                              /                   \
 134    *        need child query/ies /                     \ no child query
 135    *                            /                       \
 136    *                          |_                         _|
 137    *                +--------------+                   +----------------+
 138    *                | child/childw | ----------------> | done/output OK |
 139    *                +--------------+  children done    +----------------+
 140    */
 141 };
 142
 143 struct adns__state {
 144   adns_initflags iflags;
 145   FILE *diagfile;
 146   struct { adns_query head, tail; } timew, childw, output;
 147   int nextid, udpsocket, tcpsocket;
 148   vbuf rqbuf, tcpsend, tcprecv;
 149   int nservers, tcpserver;
 150   enum adns__tcpstate { server_disconnected, server_connecting, server_ok } tcpstate;
 151   struct timeval tcptimeout;
 152   struct server {
 153     struct in_addr addr;
 154   } servers[MAXSERVERS];
 155 };
 156
 157 /* From setup.c: */
 158
 159 void adns__vdiag(adns_state ads, const char *pfx, adns_initflags prevent,
 160                  int serv, const char *fmt, va_list al);
 161 void adns__debug(adns_state ads, int serv, const char *fmt, ...) PRINTFFORMAT(3,4);
 162 void adns__warn(adns_state ads, int serv, const char *fmt, ...) PRINTFFORMAT(3,4);
 163 void adns__diag(adns_state ads, int serv, const char *fmt, ...) PRINTFFORMAT(3,4);
 164
 165 int adns__vbuf_ensure(vbuf *vb, int want);
 166 int adns__vbuf_append(vbuf *vb, const byte *data, int len);
 167 int adns__vbuf_malloc(vbuf *vb, size_t len);
 168 /* 1=>success, 0=>realloc failed */
 169 void adns__vbuf_appendq(vbuf *vb, const byte *data, int len);
 170 void adns__vbuf_init(vbuf *vb);
 171
 172 int adns__setnonblock(adns_state ads, int fd); /* => errno value */
 173
 174 /* From submit.c: */
 175
 176 void adns__query_nomem(adns_state ads, adns_query qu);
 177 void adns__query_finish(adns_state ads, adns_query qu, adns_status stat);
 178 void adns__query_fail(adns_state ads, adns_query qu, adns_status stat);
 179
 180 /* From query.c: */
 181
 182 void adns__query_udp(adns_state ads, adns_query qu, struct timeval now);
 183 void adns__query_tcp(adns_state ads, adns_query qu, struct timeval now);
 184 adns_status adns__mkquery(adns_state ads, const char *owner, int ol, int id,
 185                           const typeinfo *typei, adns_queryflags flags);
 186
 187 /* From reply.c: */
 188
 189 void adns__procdgram(adns_state ads, const byte *dgram, int len,
 190                      int serv, struct timeval now);
 191
 192 /* From types.c: */
 193
 194 const typeinfo *adns__findtype(adns_rrtype type);
 195
 196 /* From parse.c: */
 197
 198 int vbuf__append_quoted1035(vbuf *vb, const byte *buf, int len);
 199
 200 adns_status adns__get_label(const byte *dgram, int dglen, int *max_io,
 201                             int *cbyte_io, int *lablen_r, int *labstart_r,
 202                             int *namelen_io);
 203 adns_status adns__get_domain_perm(adns_state ads, adns_query qu, int serv,
 204                                   const byte *dgram, int dglen,
 205                                   int *cbyte_io, int max, int *domainstart_r);
 206 adns_status adns__get_domain_temp(adns_state ads, adns_query qu, int serv,
 207                                   const byte *dgram, int dglen,
 208                                   int *cbyte_io, int max, int *domainstart_r);
 209 adns_status adns__get_rr_temp(adns_state ads, adns_query qu, int serv,
 210                               const byte *dgram, int dglen, int *cbyte_io,
 211                               int *type_r, int *class_r, int *rdlen_r, int *rdstart_r,
 212                               const byte *eo_dgram, int eo_dglen, int eo_cbyte,
 213                               int *eo_matched_r);
 214
 215 /* From event.c: */
 216
 217 void adns__tcp_broken(adns_state ads, const char *what, const char *why);
 218 void adns__tcp_tryconnect(adns_state ads, struct timeval now);
 219 void adns__autosys(adns_state ads, struct timeval now);
 220
 221 /* Useful static inline functions: */
 222
 223 static inline void timevaladd(struct timeval *tv_io, long ms) {
 224   struct timeval tmp;
 225   assert(ms>=0);
 226   tmp= *tv_io;
 227   tmp.tv_usec += (ms%1000)*1000000;
 228   tmp.tv_sec += ms/1000;
 229   if (tmp.tv_usec >= 1000000) { tmp.tv_sec++; tmp.tv_usec -= 1000; }
 230   *tv_io= tmp;
 231 }
 232
 233 static inline int ctype_whitespace(int c) { return c==' ' || c=='\n' || c=='\t'; }
 234 static inline int ctype_digit(int c) { return c>='0' && c<='9'; }
 235 static inline int ctype_alpha(int c) {
 236   return (c >= 'a' && c <= 'z') || (c >= 'A' || c <= 'Z');
 237 }
 238
 239 /* Useful macros */
 240
 241 #define LIST_INIT(list) ((list).head= (list).tail= 0)
 242
 243 #define LIST_UNLINK_PART(list,node,part) \
 244   do { \
 245     if ((node)->back) (node)->back->part next= (node)->part next; \
 246       else                        (list).head= (node)->part next; \
 247     if ((node)->next) (node)->next->part back= (node)->part back; \
 248       else                        (list).tail= (node)->part back; \
 249   } while(0)
 250
 251 #define LIST_LINK_TAIL_PART(list,node,part) \
 252   do { \
 253     (node)->part back= 0; \
 254     (node)->part next= (list).tail; \
 255     if ((list).tail) (list).tail->part back= (node); else (list).part head= (node); \
 256     (list).tail= (node); \
 257   } while(0)
 258
 259 #define LIST_UNLINK(list,node) LIST_UNLINK_PART(list,node,)
 260 #define LIST_LINK_TAIL(list,node) LIST_LINK_TAIL_PART(list,node,)
 261
 262 #define GETIL_B(cb) (dgram[(cb)++])
 263 #define GET_B(cb,tv) ((tv)= GETIL_B((cb)))
 264 #define GET_W(cb,tv) ((tv)=0, (tv)|=(GETIL_B((cb))<<8), (tv)|=GETIL_B(cb), (tv))
 265
 266 #endif