* - comments regarding library data structures
*/
/*
- * This file is part of adns, which is Copyright (C) 1997, 1998 Ian Jackson
+ * This file is
+ * Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk>
+ *
+ * It is part of adns, which is
+ * Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk>
+ * Copyright (C) 1999 Tony Finch <dot@dotat.at>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
#ifndef ADNS_INTERNAL_H_INCLUDED
#define ADNS_INTERNAL_H_INCLUDED
-#define PRINTFFORMAT(a,b) __attribute__((format(printf,a,b)))
+#include "config.h"
typedef unsigned char byte;
#include <stdarg.h>
#include <assert.h>
#include <unistd.h>
+#include <signal.h>
+#include <errno.h>
+#include <string.h>
#include <sys/time.h>
#include "adns.h"
+#include "dlist.h"
/* Configuration and constants */
#define MAXSERVERS 5
-#define UDPMAXRETRIES /*15*/5
+#define MAXSORTLIST 15
+#define UDPMAXRETRIES 15
#define UDPRETRYMS 2000
#define TCPMS 30000
-#define LOCALRESOURCEMS 20
+#define MAXTTLBELIEVE (7*86400) /* any TTL > 7 days is capped */
#define DNS_PORT 53
#define DNS_MAXUDP 512
#define DNS_MAXDOMAIN 255
#define DNS_HDRSIZE 12
+#define DNS_IDOFFSET 0
#define DNS_CLASS_IN 1
+#define DNS_INADDR_ARPA "in-addr", "arpa"
+
+#define MAX_POLLFDS ADNS_POLLFDS_RECOMMENDED
+
+typedef enum {
+ cc_user,
+ cc_entex,
+ cc_freq
+} consistency_checks;
+
typedef enum {
rcode_noerror,
rcode_formaterror,
byte *buf;
} vbuf;
-typedef union {
- void *ext;
- int dmaddr_index;
-} qcontext;
+typedef struct {
+ adns_state ads;
+ adns_query qu;
+ int serv;
+ const byte *dgram;
+ int dglen, nsstart, nscount, arcount;
+ struct timeval now;
+} parseinfo;
typedef struct {
adns_rrtype type;
* and will not be null-terminated by convstring.
*/
- adns_status (*parse)(adns_query qu, int serv,
- const byte *dgram, int dglen, int cbyte, int max,
- void *store_r);
+ adns_status (*parse)(const parseinfo *pai, int cbyte, int max, void *store_r);
/* Parse one RR, in dgram of length dglen, starting at cbyte and
* extending until at most max.
*
*
* If there is an overrun which might indicate truncation, it should set
* *rdstart to -1; otherwise it may set it to anything else positive.
+ *
+ * nsstart is the offset of the authority section.
*/
- int (*diff_needswap)(const void *datap_a, const void *datap_b);
- /* Returns >0 if RR a should be strictly after RR b in the sort order,
+ int (*diff_needswap)(adns_state ads, const void *datap_a, const void *datap_b);
+ /* Returns !0 if RR a should be strictly after RR b in the sort order,
* 0 otherwise. Must not fail.
*/
} typeinfo;
typedef struct allocnode {
- struct allocnode *next;
+ struct allocnode *next, *back;
} allocnode;
union maxalign {
union maxalign *up;
} data;
+typedef struct {
+ void *ext;
+ void (*callback)(adns_query parent, adns_query child);
+ union {
+ adns_rr_addr ptr_parent_addr;
+ adns_rr_hostaddr *hostaddr;
+ } info;
+} qcontext;
+
struct adns__query {
adns_state ads;
- enum { query_udp, query_tcpwait, query_tcpsent, query_child, query_done } state;
+ enum { query_tosend, query_tcpwait, query_tcpsent, query_child, query_done } state;
adns_query back, next, parent;
struct { adns_query head, tail; } children;
struct { adns_query back, next; } siblings;
- struct allocnode *allocations;
- int interim_allocd;
+ struct { allocnode *head, *tail; } allocations;
+ int interim_allocd, preserved_allocd;
void *final_allocspace;
-
+
const typeinfo *typei;
byte *query_dgram;
int query_dglen;
* we found a cname (this corresponds to cname_dgram in the query
* structure). type is set from the word go. nrrs and rrs
* are set together, when we find how many rrs there are.
+ * owner is set during querying unless we're doing searchlist,
+ * in which case it is set only when we find an answer.
*/
byte *cname_dgram;
int cname_dglen, cname_begin;
/* If non-0, has been allocated using . */
+
+ vbuf search_vb;
+ int search_origlen, search_pos, search_doneabs;
+ /* Used by the searching algorithm. The query domain in textual form
+ * is copied into the vbuf, and _origlen set to its length. Then
+ * we walk the searchlist, if we want to. _pos says where we are
+ * (next entry to try), and _doneabs says whether we've done the
+ * absolute query yet (0=not yet, 1=done, -1=must do straight away,
+ * but not done yet). If flags doesn't have adns_qf_search then
+ * the vbuf is initialised but empty and everything else is zero.
+ */
int id, flags, udpretries;
int udpnextserver;
unsigned long udpsent, tcpfailed; /* bitmap indexed by server */
struct timeval timeout;
- qcontext context;
+ time_t expires; /* Earliest expiry time of any record we used. */
+
+ qcontext ctx;
/* Possible states:
*
- * state Queue child id nextudpserver sentudp failedtcp
+ * state Queue child id nextudpserver udpsent tcpfailed
*
- * udp NONE null >=0 0 zero zero
- * udp timew null >=0 any nonzero zero
- * udp NONE null >=0 any nonzero zero
+ * tosend NONE null >=0 0 zero zero
+ * tosend timew null >=0 any nonzero zero
+ * tosend NONE null >=0 any nonzero zero
*
- * tcpwait timew null >=0 irrelevant zero any
- * tcpsent timew null >=0 irrelevant zero any
+ * tcpwait timew null >=0 irrelevant any any
+ * tcpsent timew null >=0 irrelevant any any
*
* child childw set >=0 irrelevant irrelevant irrelevant
+ * child NONE null >=0 irrelevant irrelevant irrelevant
* done output null -1 irrelevant irrelevant irrelevant
*
+ * Queries are only not on a queue when they are actually being processed.
+ *
* +------------------------+
* START -----> | udp/NONE |
* +------------------------+
struct adns__state {
adns_initflags iflags;
FILE *diagfile;
+ int configerrno;
struct { adns_query head, tail; } timew, childw, output;
+ adns_query forallnext;
int nextid, udpsocket, tcpsocket;
vbuf tcpsend, tcprecv;
- int nservers, tcpserver;
+ int nservers, nsortlist, nsearchlist, searchndots, tcpserver, tcprecv_skip;
enum adns__tcpstate { server_disconnected, server_connecting, server_ok } tcpstate;
struct timeval tcptimeout;
+ struct sigaction stdsigpipe;
+ sigset_t stdsigmask;
+ struct pollfd pollfds_buf[MAX_POLLFDS];
struct server {
struct in_addr addr;
} servers[MAXSERVERS];
+ struct sortlist {
+ struct in_addr base, mask;
+ } sortlist[MAXSORTLIST];
+ char **searchlist;
};
/* From setup.c: */
int adns__setnonblock(adns_state ads, int fd); /* => errno value */
+void adns__checkqueues(adns_state ads); /* expensive walk, for checking */
/* From general.c: */
* vb before using the return value.
*/
+void adns__isort(void *array, int nobjs, int sz, void *tempbuf,
+ int (*needswap)(void *context, const void *a, const void *b),
+ void *context);
+/* Does an insertion sort of array which must contain nobjs objects
+ * each sz bytes long. tempbuf must point to a buffer at least
+ * sz bytes long. needswap should return !0 if a>b (strictly, ie
+ * wrong order) 0 if a<=b (ie, order is fine).
+ */
+
+void adns__sigpipe_protect(adns_state);
+void adns__sigpipe_unprotect(adns_state);
+/* If SIGPIPE protection is not disabled, will block all signals except
+ * SIGPIPE, and set SIGPIPE's disposition to SIG_IGN. (And then restore.)
+ * Each call to _protect must be followed by a call to _unprotect before
+ * any significant amount of code gets to run.
+ */
+
/* From transmit.c: */
adns_status adns__mkquery(adns_state ads, vbuf *vb, int *id_r,
const char *owner, int ol,
const typeinfo *typei, adns_queryflags flags);
-/* Assembles a query packet in vb, and returns id at *id_r. */
+/* Assembles a query packet in vb. A new id is allocated and returned.
+ */
adns_status adns__mkquery_frdgram(adns_state ads, vbuf *vb, int *id_r,
const byte *qd_dgram, int qd_dglen, int qd_begin,
* reestablishment and retry.
*/
-void adns__query_udp(adns_query qu, struct timeval now);
-/* Query must be in state udp/NONE; it will be moved to a new state,
+void adns__query_send(adns_query qu, struct timeval now);
+/* Query must be in state tosend/NONE; it will be moved to a new state,
* and no further processing can be done on it for now.
* (Resulting state is one of udp/timew, tcpwait/timew (if server not connected),
* tcpsent/timew, child/childw or done/output.)
+ * __query_send may decide to use either UDP or TCP depending whether
+ * _qf_usevc is set (or has become set) and whether the query is too
+ * large.
*/
/* From query.c: */
-int adns__internal_submit(adns_state ads, adns_query *query_r,
- const typeinfo *typei, vbuf *qumsg_vb, int id,
- adns_queryflags flags, struct timeval now,
- adns_status failstat, const qcontext *ctx);
+adns_status adns__internal_submit(adns_state ads, adns_query *query_r,
+ const typeinfo *typei, vbuf *qumsg_vb, int id,
+ adns_queryflags flags, struct timeval now,
+ const qcontext *ctx);
/* Submits a query (for internal use, called during external submits).
*
* The new query is returned in *query_r, or we return adns_s_nomemory.
* the memory for it is _taken over_ by this routine whether it
* succeeds or fails (if it succeeds, the vbuf is reused for qu->vb).
*
- * If failstat is nonzero then if we are successful in creating the query
- * it is immediately failed with code failstat (but _submit still succeds).
+ * *ctx is copied byte-for-byte into the query.
+ *
+ * When the child query is done, ctx->callback will be called. The
+ * child will already have been taken off both the global list of
+ * queries in ads and the list of children in the parent. The child
+ * will be freed when the callback returns. The parent will have been
+ * taken off the global childw queue.
+ *
+ * The callback should either call adns__query_done, if it is
+ * complete, or adns__query_fail, if an error has occurred, in which
+ * case the other children (if any) will be cancelled. If the parent
+ * has more unfinished children (or has just submitted more) then the
+ * callback may choose to wait for them - it must then put the parent
+ * back on the childw queue.
+ */
+
+void adns__search_next(adns_state ads, adns_query qu, struct timeval now);
+/* Walks down the searchlist for a query with adns_qf_search.
+ * The query should have just had a negative response, or not had
+ * any queries sent yet, and should not be on any queue.
+ * The query_dgram if any will be freed and forgotten and a new
+ * one constructed from the search_* members of the query.
*
- * ctx is copied byte-for-byte into the query.
+ * Cannot fail (in case of error, calls adns__query_fail).
*/
void *adns__alloc_interim(adns_query qu, size_t sz);
+void *adns__alloc_preserved(adns_query qu, size_t sz);
/* Allocates some memory, and records which query it came from
* and how much there was.
*
- * If an error occurs in the query, all its memory is simply freed.
- *
- * If the query succeeds, one large buffer will be made which is
- * big enough for all these allocations, and then adns__alloc_final
- * will get memory from this buffer.
+ * If an error occurs in the query, all the memory from _interim is
+ * simply freed. If the query succeeds, one large buffer will be made
+ * which is big enough for all these allocations, and then
+ * adns__alloc_final will get memory from this buffer.
*
* _alloc_interim can fail (and return 0).
* The caller must ensure that the query is failed.
*
- * adns__alloc_interim_{only,fail}(qu,0) will not return 0,
- * but it will not necessarily return a distinct pointer each time.
+ * The memory from _preserved is is kept and transferred into the
+ * larger buffer - unless we run out of memory, in which case it too
+ * is freed. When you use _preserved you have to add code to the
+ * x_nomem error exit case in adns__makefinal_query to clear out the
+ * pointers you made to those allocations, because that's when they're
+ * thrown away; you should also make a note in the declaration of
+ * those pointer variables, to note that they are _preserved rather
+ * than _interim. If they're in the answer, note it here:
+ * answer->cname and answer->owner are _preserved.
+ */
+
+void adns__transfer_interim(adns_query from, adns_query to, void *block, size_t sz);
+/* Transfers an interim allocation from one query to another, so that
+ * the `to' query will have room for the data when we get to makefinal
+ * and so that the free will happen when the `to' query is freed
+ * rather than the `from' query.
+ *
+ * It is legal to call adns__transfer_interim with a null pointer; this
+ * has no effect.
+ *
+ * _transfer_interim also ensures that the expiry time of the `to' query
+ * is no later than that of the `from' query, so that child queries'
+ * TTLs get inherited by their parents.
*/
void *adns__alloc_mine(adns_query qu, size_t sz);
void adns__makefinal_block(adns_query qu, void **blpp, size_t sz);
void adns__makefinal_str(adns_query qu, char **strp);
-void adns__reset_cnameonly(adns_query qu);
-/* Resets all of the memory management stuff etc. to
- * take account of only the CNAME. Used when we find an error somewhere
- * and want to just report the error (with perhaps CNAME info), and also
- * when we're halfway through RRs in a datagram and discover that we
- * need to retry the query.
+void adns__reset_preserved(adns_query qu);
+/* Resets all of the memory management stuff etc. to take account of
+ * only the _preserved stuff from _alloc_preserved. Used when we find
+ * an error somewhere and want to just report the error (with perhaps
+ * CNAME, owner, etc. info), and also when we're halfway through RRs
+ * in a datagram and discover that we need to retry the query.
*/
void adns__query_done(adns_query qu);
/* From reply.c: */
void adns__procdgram(adns_state ads, const byte *dgram, int len,
- int serv, struct timeval now);
+ int serv, int viatcp, struct timeval now);
/* From types.c: */
* serv may be -1 and qu may be 0 - they are used for error reporting only.
*/
+adns_status adns__parse_domain_more(findlabel_state *fls, adns_state ads,
+ adns_query qu, vbuf *vb, parsedomain_flags flags,
+ const byte *dgram);
+/* Like adns__parse_domain, but you pass it a pre-initialised findlabel_state,
+ * for continuing an existing domain or some such of some kind. Also, unlike
+ * _parse_domain, the domain data will be appended to vb, rather than replacing
+ * the existing contents.
+ */
+
adns_status adns__findrr(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,
+ int *type_r, int *class_r, unsigned long *ttl_r,
+ int *rdlen_r, int *rdstart_r,
int *ownermatchedquery_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 ownermatchedquery_r != 0 then the owner domain of this
- * RR will be compared with that in the query (or, if the query
- * has gone to a CNAME lookup, with the canonical name).
- * In this case, *ownermatchedquery_r will be set to 0 or 1.
- * The query datagram (or CNAME datagram) MUST be valid and not truncated.
- *
- * 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.
- *
- * qu must obviously be non-null.
- *
- * If an error is returned then *type_r will be undefined too.
- */
+/* 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, TTL and RRdata length and start are returned iff
+ * the corresponding pointer variables are not null. type_r, class_r
+ * and ttl_r may not be null. The TTL will be capped.
+ *
+ * If ownermatchedquery_r != 0 then the owner domain of this
+ * RR will be compared with that in the query (or, if the query
+ * has gone to a CNAME lookup, with the canonical name).
+ * In this case, *ownermatchedquery_r will be set to 0 or 1.
+ * The query datagram (or CNAME datagram) MUST be valid and not truncated.
+ *
+ * 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.
+ *
+ * qu must obviously be non-null.
+ *
+ * If an error is returned then *type_r will be undefined too.
+ */
+
+adns_status adns__findrr_anychk(adns_query qu, int serv,
+ const byte *dgram, int dglen, int *cbyte_io,
+ int *type_r, int *class_r, unsigned long *ttl_r,
+ int *rdlen_r, int *rdstart_r,
+ const byte *eo_dgram, int eo_dglen, int eo_cbyte,
+ int *eo_matched_r);
+/* Like adns__findrr_checked, except that the datagram and
+ * owner to compare with can be specified explicitly.
+ *
+ * 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.
+ */
+
+void adns__update_expires(adns_query qu, unsigned long ttl, struct timeval now);
+/* Updates the `expires' field in the query, so that it doesn't exceed
+ * now + ttl.
+ */
int vbuf__append_quoted1035(vbuf *vb, const byte *buf, int len);
/* From event.c: */
void adns__tcp_broken(adns_state ads, const char *what, const char *why);
+void adns__tcp_closenext(adns_state ads);
void adns__tcp_tryconnect(adns_state ads, struct timeval now);
void adns__autosys(adns_state ads, struct timeval now);
-/* Make all the system calls we want to if the application wants us to. */
+/* Make all the system calls we want to if the application wants us to.
+ * Must not be called from within adns internal processing functions,
+ * lest we end up in recursive descent !
+ */
+
+void adns__must_gettimeofday(adns_state ads, const struct timeval **now_io,
+ struct timeval *tv_buf);
+void adns__timeouts(adns_state ads, int act,
+ struct timeval **tv_io, struct timeval *tvbuf,
+ struct timeval now);
+int adns__pollfds(adns_state ads, struct pollfd pollfds_buf[MAX_POLLFDS]);
+void adns__fdevents(adns_state ads,
+ const struct pollfd *pollfds, int npollfds,
+ int maxfd, const fd_set *readfds,
+ const fd_set *writefds, const fd_set *exceptfds,
+ struct timeval now, int *r_r);
+int adns__internal_check(adns_state ads,
+ adns_query *query_io,
+ adns_answer **answer,
+ void **context_r);
+
+/* From check.c: */
+
+void adns__consistency(adns_state ads, adns_query qu, consistency_checks cc);
/* Useful static inline functions: */
static inline int ctype_whitespace(int c) { return c==' ' || c=='\n' || c=='\t'; }
static inline int ctype_digit(int c) { return c>='0' && c<='9'; }
static inline int ctype_alpha(int c) {
- return (c >= 'a' && c <= 'z') || (c >= 'A' || c <= 'Z');
+ return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z');
}
+static inline int ctype_822special(int c) { return strchr("()<>@,;:\\\".[]",c) != 0; }
+
+static inline int errno_resources(int e) { return e==ENOMEM || e==ENOBUFS; }
/* Useful macros */
(( ((sz)+sizeof(union maxalign)-1) / sizeof(union maxalign) ) \
* sizeof(union maxalign) )
-#define LIST_INIT(list) ((list).head= (list).tail= 0)
-
-#define LIST_UNLINK_PART(list,node,part) \
- do { \
- if ((node)->back) (node)->back->part next= (node)->part next; \
- else (list).head= (node)->part next; \
- if ((node)->next) (node)->next->part back= (node)->part back; \
- else (list).tail= (node)->part back; \
- } while(0)
-
-#define LIST_LINK_TAIL_PART(list,node,part) \
- do { \
- (node)->part next= 0; \
- (node)->part back= (list).tail; \
- if ((list).tail) (list).tail->part next= (node); else (list).part head= (node); \
- (list).tail= (node); \
- } while(0)
-
-#define LIST_UNLINK(list,node) LIST_UNLINK_PART(list,node,)
-#define LIST_LINK_TAIL(list,node) LIST_LINK_TAIL_PART(list,node,)
-
#define GETIL_B(cb) (((dgram)[(cb)++]) & 0x0ff)
#define GET_B(cb,tv) ((tv)= GETIL_B((cb)))
#define GET_W(cb,tv) ((tv)=0, (tv)|=(GETIL_B((cb))<<8), (tv)|=GETIL_B(cb), (tv))
+#define GET_L(cb,tv) ( (tv)=0, \
+ (tv)|=(GETIL_B((cb))<<24), \
+ (tv)|=(GETIL_B((cb))<<16), \
+ (tv)|=(GETIL_B((cb))<<8), \
+ (tv)|=GETIL_B(cb), \
+ (tv) )
#endif
~ianmdlvl / adns.git / blobdiff