Add A record parsing.

[adns] / src / parse.c

diff --git a/src/parse.c b/src/parse.c
index 2a9dd94b327462959be98d87ffbcbd6d0c3f2ac5..957b57232994121321d1daab9632d889d9b5e906 100644 (file)
--- a/src/parse.c
+++ b/src/parse.c
@@ -26,73 +26,89 @@ int vbuf__append_quoted1035(vbuf *vb, const byte *buf, int len) {
   return 1;
 }
 
   return 1;
 }
 

-adns_status adns__get_label(const byte *dgram, int dglen, int *max_io,
-                           int *cbyte_io, int *lablen_r, int *labstart_r,
-                           int *namelen_io) {
-  /* If succeeds, *lablen_r may be set to -1 to indicate truncation/overrun */
-  int max, cbyte, lablen, namelen;
+void adns__findlabel_start(findlabel_state *fls,
+                          adns_state ads, int serv,
+                          const byte *dgram, int dglen, int max,
+                          int dmbegin, int *dmend_rlater) {
+  fls->ads= ads;
+  fls->serv= serv;
+  fls->dgram= dgram;
+  fls->dglen= dglen;
+  fls->max= max;
+  fls->cbyte= dmbegin;
+  fls->namelen= 0;
+  fls->dmend_r= dmend_rlater;
+  fls->namelen_r= namelen_rlater;
+}

 
 

-  max= *max_io;
-  cbyte= *cbyte_io;
-  
+adns_status adns__findlabel_next(findlabel_state fls,
+                                int *lablen_r, int *labstart_r) {
+  int lablen, jumped;
+
+  jumped= 0;

   for (;;) {
   for (;;) {

-    if (cbyte+2 > max) goto x_truncated;
-    GET_W(cbyte,lablen);
+    fls->cbyte += 2;
+    if (fls->cbyte > fls->dglen) goto x_truncated;
+    if (fls->cbyte > fls->max) goto x_serverfaulty;
+    GET_W(fls->cbyte-2,lablen);

     if (!(lablen & 0x0c000)) break;
     if ((lablen & 0x0c000) != 0x0c000) return adns_s_unknownreply;
     if (!(lablen & 0x0c000)) break;
     if ((lablen & 0x0c000) != 0x0c000) return adns_s_unknownreply;

-    if (cbyte_io) { *cbyte_io= cbyte; cbyte_io= 0; }
-    cbyte= DNS_HDRSIZE+(lablen&0x3fff);
-    *max_io= max= dglen;
+    if (jumped++) {
+      adns__diag(ads,serv,"compressed datagram contains loop");
+      return adns_s_serverfaulty;
+    }
+    if (fls->dmend_r) *(fls->dmend_r)= fls->cbyte;
+    fls->cbyte= DNS_HDRSIZE+(lablen&0x3fff);
+    fls->dmend_r= 0; fls->max= fls->dglen+1;

   }
   }

-  if (labstart_r) *labstart_r= cbyte;

   if (lablen) {
   if (lablen) {

-    namelen= *namelen_io;
-    if (namelen) namelen++;
-    namelen+= lablen;
-    if (namelen > DNS_MAXDOMAIN) return adns_s_domaintoolong;
-    *namelen_io= namelen;
-    cbyte+= lablen;
-    if (cbyte > max) goto x_truncated;
+    if (fls->namelen) fls->namelen++;
+    fls->namelen+= lablen;
+    if (fls->namelen > DNS_MAXDOMAIN) return adns_s_domaintoolong;
+    fls->cbyte+= lablen;
+    if (fls->cbyte > fls->dglen) goto x_truncated;
+    if (fls->cbyte > fls->max) goto x_serverfaulty;
+  } else {
+    if (fls->dmend_r) *(fls->dmend_r)= fls->cbyte;
+    if (fls->namelen_r) *(fls->namelen_r)= fls->namelen;

   }
   }

-  if (cbyte_io) *cbyte_io= cbyte;
+  if (labstart_r) *labstart_r= fls->cbyte;

   *lablen_r= lablen;
   return adns_s_ok;
 
  x_truncated:
   *lablen_r= -1;
   return adns_s_ok;
   *lablen_r= lablen;
   return adns_s_ok;
 
  x_truncated:
   *lablen_r= -1;
   return adns_s_ok;

+
+ x_serverfaulty: 
+  adns__diag(ads,serv,"label in domain runs beyond end of domain");
+  return adns_s_serverfaulty;

 }
 
 }
 

-adns_status adns__get_domain_perm(adns_state ads, adns_query qu, int serv,
-                                 const byte *dgram, int dglen,
-                                 int *cbyte_io, int max, int *domainstart_r) {
-  /* Returns 0     for OK (*domainstart_r >=0) or truncated (*domainstart_r == -1)
-   *      or any other adns_s_* value.
-   */
-  int cbyte, sused, lablen, labstart, namelen, i, ch;
+adns_status adns__parse_domain(adns_state ads, int serv, vbuf *vb, int flags,
+                              const byte *dgram, int dglen,
+                              int *cbyte_io, int max) {
+  findlabel_state fls;
+  
+  int cbyte, lablen, labstart, namelen, i, ch;

   adns_status st;
 
   adns_status st;
 

-  /* If we follow a pointer we set cbyte_io to 0 to indicate that
-   * we've lost our original starting and ending points; we don't
-   * put the end of the pointed-to thing into the original *cbyte_io.
-   */
-  cbyte= *cbyte_io;
-  sused= qu->ans.used;
-  namelen= 0;
+  ands__findlabel_start(&fls,ads,serv, dgram,dglen,max, *cbyte_io,cbyte_io);
+  vb->used= 0;

   for (;;) {
   for (;;) {

-    st= adns__get_label(dgram,dglen,&max, &cbyte,&lablen,&labstart,&namelen);
+    st= adns__findlabel_next(&fls,&lablen,&labstart);

     if (st) return st;
     if (st) return st;

-    if (lablen<0) goto x_truncated;
+    if (lablen<0) { vb->used=0; return adns_s_ok; }

     if (!lablen) break;
     if (!lablen) break;

-    if (qu->ans.used != sused)
+    if (vb->used)

       if (!adns__vbuf_append(&qu->ans,".",1)) return adns_s_nolocalmem;
       if (!adns__vbuf_append(&qu->ans,".",1)) return adns_s_nolocalmem;

-    if (qu->flags & adns_qf_anyquote) {
+    if (flags & adns_qf_anyquote) {

       if (!vbuf__append_quoted1035(&qu->ans,dgram+labstart,lablen))
        return adns_s_nolocalmem;
     } else {
       if (!ctype_alpha(dgram[labstart])) return adns_s_invaliddomain;
       if (!vbuf__append_quoted1035(&qu->ans,dgram+labstart,lablen))
        return adns_s_nolocalmem;
     } else {
       if (!ctype_alpha(dgram[labstart])) return adns_s_invaliddomain;

-      for (i= cbyte+1; i<cbyte+lablen; i++) {
-       ch= dgram[cbyte];
+      for (i= labstart+1; i<labstart+lablen; i++) {
+       ch= dgram[i];

        if (ch != '-' && !ctype_alpha(ch) && !ctype_digit(ch))
          return adns_s_invaliddomain;
       }
        if (ch != '-' && !ctype_alpha(ch) && !ctype_digit(ch))
          return adns_s_invaliddomain;
       }


@@ -100,58 +116,85 @@ adns_status adns__get_domain_perm(adns_state ads, adns_query qu, int serv,
        return adns_s_nolocalmem;
     }
   }
        return adns_s_nolocalmem;
     }
   }

-  if (cbyte_io) *cbyte_io= cbyte;

   if (!adns__vbuf_append(&qu->ans,"",1)) return adns_s_nolocalmem;
   if (!adns__vbuf_append(&qu->ans,"",1)) return adns_s_nolocalmem;

-  *domainstart_r= sused;

   return adns_s_ok;
   return adns_s_ok;

-
- x_truncated:
-  *domainstart_r= -1;
-  return cbyte_io ? -1 : adns_s_serverfaulty;

 }
 }

-    
-adns_status adns__get_domain_temp(adns_state ads, adns_query qu, int serv,
-                                 const byte *dgram, int dglen,
-                                 int *cbyte_io, int max, int *domainstart_r) {
-  int sused;
+       
+const char *adns__diag_domain(adns_state ads, int serv, vbuf *vb, int flags,
+                             const byte *dgram, int dglen, int cbyte) {

   adns_status st;
 
   adns_status st;
 

-  sused= qu->ans.used;
-  st= adns__get_domain_perm(ads,qu,serv,dgram,dglen,cbyte_io,max,domainstart_r);
-  qu->ans.used= sused;
-  return st;
+  st= adns__parse_domain(ads,serv,vb,qu->flags, dgram,dglen, &cbyte,dglen);
+  if (st) {
+    vb->used= 0;
+    adns__vbuf_appendstr(vb,"<bad format... ");
+    adns__vbuf_appendstr(vb,adns_strerror(st));
+    adns__vbuf_appendstr(vb,">");
+    adns__vbuf_append(vb,"",1);
+  }
+  if (!vb.used) {
+    adns__vbuf_appendstr(vb,"<truncated ...>");
+    adns__vbuf_append(vb,"",1);
+  }
+  return vb->buf;

 }
 }

-
-adns_status adns__get_rr_temp(adns_state ads, adns_query qu, int serv,
-                             const byte *dgram, int dglen, int *cbyte_io,
-                             int *type_r, int *class_r, int *rdlen_r, int *rdstart_r,
-                             const byte *eo_dgram, int eo_dglen, int eo_cbyte,
-                             int *eo_matched_r) {
-  /* _s_ok can have *type_r == -1 and other output invalid, for truncation
-   * type_r and class_r must be !0, other _r may be 0.
-   * eo_dgram==0 for no comparison, otherwise all eo_ must be valid.
+    
+adns_status adns__findrr(adns_state ads, int serv,
+                        const byte *dgram, int dglen, int *cbyte_io,
+                        int *type_r, int *class_r, int *rdlen_r, int *rdstart_r,
+                        const byte *eo_dgram, int eo_dglen, int eo_cbyte,
+                        int *eo_matched_r) {
+  /* Finds the extent and some of the contents of an RR in a datagram
+   * and does some checks.  The datagram is *dgram, length dglen, and
+   * the RR starts at *cbyte_io (which is updated afterwards to point
+   * to the end of the RR).
+   *
+   * The type, class and RRdata length and start are returned iff
+   * the corresponding pointer variables are not null.  type_r and
+   * class_r may not be null.
+   *
+   * If the caller thinks they know what the owner of the RR ought to
+   * be they can pass in details in eo_*: this is another (or perhaps
+   * the same datagram), and a pointer to where the putative owner
+   * starts in that datagram.  In this case *eo_matched_r will be set
+   * to 1 if the datagram matched or 0 if it did not.  Either
+   * both eo_dgram and eo_matched_r must both be non-null, or they
+   * must both be null (in which case eo_dglen and eo_cbyte will be ignored).
+   * The eo datagram and contained owner domain MUST be valid and
+   * untruncated.
+   *
+   * If there is truncation then *type_r will be set to -1 and
+   * *cbyte_io, *class_r, *rdlen_r, *rdstart_r and *eo_matched_r will be
+   * undefined.
+   *
+   * If an error is returned then *type_r will be undefined too.

    */
    */

-  int cbyte, tmp, rdlen, mismatch;
+  findlabel_state fls, eo_fls;
+  int cbyte;
+  
+  int tmp, rdlen, mismatch;

   int max, lablen, labstart, namelen, ch;
   int eo_max, eo_lablen, eo_labstart, eo_namelen, eo_ch;
   adns_status st;
 
   cbyte= *cbyte_io;
   int max, lablen, labstart, namelen, ch;
   int eo_max, eo_lablen, eo_labstart, eo_namelen, eo_ch;
   adns_status st;
 
   cbyte= *cbyte_io;

-  mismatch= eo_dgram ? 1 : 0;

 
 

-  namelen= 0; eo_namelen= 0;
-  max= dglen; eo_max= eo_dglen;
+  ands__findlabel_start(&fls,ads,serv, dgram,dglen,dglen,cbyte,&cbyte);
+  if (eo_dgram) {
+    ands__findlabel_start(&eo_fls,ads,serv, eo_dgram,eo_dglen,eo_dglen,eo_cbyte,0);
+    mismatch= 0;
+  } else {
+    mismatch= 1;
+  }
+  

   for (;;) {
   for (;;) {

-    st= adns__get_label(dgram,dglen,&max,
-                       &cbyte,&lablen,&labstart,&namelen);
+    st= adns__findlabel_next(&fls,&lablen,&labstart);

     if (st) return st;
     if (lablen<0) goto x_truncated;
 
     if (!mismatch) {
     if (st) return st;
     if (lablen<0) goto x_truncated;
 
     if (!mismatch) {

-      st= adns__get_label(eo_dgram,eo_dglen,&eo_max,
-                         &eo_cbyte,&eo_lablen,&eo_labstart,&eo_namelen);
-      if (st) return st;
-      assert(eo_lablen>=0);
+      st= adns__findlabel_next(&eo_fls,&eo_lablen,&eo_labstart);
+      assert(!st); assert(eo_lablen>=0);

       if (lablen != eo_lablen) mismatch= 1;
       while (!mismatch && lablen-- > 0) {
        ch= dgram[labstart++]; if (ctype_alpha(ch)) ch &= ~32;
       if (lablen != eo_lablen) mismatch= 1;
       while (!mismatch && lablen-- > 0) {
        ch= dgram[labstart++]; if (ctype_alpha(ch)) ch &= ~32;