-/**/
+/*
+ * internal.h
+ * - declarations of private objects with external linkage (adns__*)
+ * - definitons of internal macros
+ * - comments regarding library data structures
+ */
+/*
+ * This file is part of adns, which is
+ * Copyright (C) 1997-2000,2003,2006 Ian Jackson
+ * Copyright (C) 1999-2000,2003,2006 Tony Finch
+ * Copyright (C) 1991 Massachusetts Institute of Technology
+ * (See the file INSTALL for full details.)
+ *
+ * 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
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
#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 <stdlib.h>
#include <sys/time.h>
#include "adns.h"
+#include "dlist.h"
+
+#ifdef ADNS_REGRESS_TEST
+# include "hredirect.h"
+#endif
/* Configuration and constants */
#define MAXSERVERS 5
-#define MAXUDPRETRIES 15
+#define MAXSORTLIST 15
+#define UDPMAXRETRIES 15
#define UDPRETRYMS 2000
-#define TCPMS 30000
-#define LOCALRESOURCEMS 20
-#define MAXUDPDGRAM 512
-#define NSPORT 53
-#define MAXDNAME 255
+#define TCPWAITMS 30000
+#define TCPCONNMS 14000
+#define TCPIDLEMS 30000
+#define MAXTTLBELIEVE (7*86400) /* any TTL > 7 days is capped */
+
+#define DNS_PORT 53
+#define DNS_MAXUDP 512
+#define DNS_MAXLABEL 63
+#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 DNS_IP6_ARPA "ip6", "arpa"
+
+#define MAX_POLLFDS ADNS_POLLFDS_RECOMMENDED
+
+/* Some preprocessor hackery */
+
+#define GLUE(x, y) GLUE_(x, y)
+#define GLUE_(x, y) x##y
+
+/* C99 macro `...' must match at least one argument, so the naive definition
+ * `#define CAR(car, ...) car' won't work. But it's easy to arrange for the
+ * tail to be nonempty if we're just going to discard it anyway. */
+#define CAR(...) CAR_(__VA_ARGS__, _)
+#define CAR_(car, ...) car
+
+/* Extracting the tail of an argument list is rather more difficult. The
+ * following trick is based on one by Laurent Deniau to count the number of
+ * arguments to a macro, simplified in two ways: (a) it only handles up to
+ * eight arguments, and (b) it only needs to distinguish the one-argument
+ * case from many arguments. */
+#define CDR(...) CDR_(__VA_ARGS__, m, m, m, m, m, m, m, 1, _)(__VA_ARGS__)
+#define CDR_(_1, _2, _3, _4, _5, _6, _7, _8, n, ...) CDR_##n
+#define CDR_1(_)
+#define CDR_m(_, ...) __VA_ARGS__
+
+typedef enum {
+ cc_user,
+ cc_entex,
+ cc_freq
+} consistency_checks;
+
+typedef enum {
+ rcode_noerror,
+ rcode_formaterror,
+ rcode_servfail,
+ rcode_nxdomain,
+ rcode_notimp,
+ rcode_refused
+} dns_rcode;
/* Shared data structures */
-typedef union {
- adns_status status;
- char *cp;
- adns_rrtype type;
- int i;
- struct in_addr ia;
- unsigned long ul;
-} rr_align;
-
typedef struct {
int used, avail;
byte *buf;
} vbuf;
-typedef union {
+typedef struct {
+ adns_state ads;
+ adns_query qu;
+ int serv;
+ const byte *dgram;
+ int dglen, nsstart, nscount, arcount;
+ struct timeval now;
+} parseinfo;
+
+union gen_addr {
+ struct in_addr v4;
+ struct in6_addr v6;
+};
+
+struct af_addr { int af; union gen_addr addr; };
+
+#define NREVDOMAINS 2 /* keep in sync with addrfam! */
+struct revparse_state {
+ unsigned map; /* which domains are still live */
+ byte ipv[NREVDOMAINS][32]; /* address components so far */
+};
+
+union checklabel_state {
+ struct revparse_state ptr;
+};
+
+typedef struct {
void *ext;
- int dmaddr_index;
+ void (*callback)(adns_query parent, adns_query child);
+
+ union {
+ struct {
+ adns_rrtype rev_rrtype;
+ struct af_addr addr;
+ } ptr;
+ } tinfo; /* type-specific state for the query itself: zero-init if you
+ * don't know better. */
+
+ union {
+ adns_rr_hostaddr *hostaddr;
+ } pinfo; /* state for use by parent's callback function */
} qcontext;
+typedef struct typeinfo {
+ adns_rrtype typekey;
+ const char *rrtname;
+ const char *fmtname;
+ int fixed_rrsz;
+
+ void (*makefinal)(adns_query qu, void *data);
+ /* Change memory management of *data.
+ * Previously, used alloc_interim, now use alloc_final.
+ */
+
+ adns_status (*convstring)(vbuf *vb, const void *data);
+ /* Converts the RR data to a string representation in vbuf.
+ * vbuf will be appended to (it must have been initialised),
+ * and will not be null-terminated by convstring.
+ */
+
+ 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.
+ *
+ * The RR should be stored at *store_r, of length qu->typei->getrrsz().
+ *
+ * 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)(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.
+ */
+
+ adns_status (*checklabel)(adns_state ads, adns_queryflags flags,
+ union checklabel_state *cls, qcontext *ctx,
+ int labnum, const char *label, int lablen);
+ /* Check a label from the query domain string. The label is not
+ * necessarily null-terminated. The hook can refuse the query's submission
+ * by returning a nonzero status. State can be stored in *cls between
+ * calls, and useful information can be stashed in ctx->tinfo, to be stored
+ * with the query (e.g., it will be available to the parse hook). This
+ * hook can detect a first call because labnum is zero, and a final call
+ * because lablen is zero.
+ */
+
+ void (*postsort)(adns_state ads, void *array, int nrrs,int rrsz,
+ const struct typeinfo *typei);
+ /* Called immediately after the RRs have been sorted, and may rearrange
+ * them. (This is really for the benefit of SRV's bizarre weighting
+ * stuff.) May be 0 to mean nothing needs to be done.
+ */
+
+ int (*getrrsz)(const struct typeinfo *typei, adns_rrtype type);
+ /* Return the output resource-record element size; if this is null, then
+ * the rrsz member can be used.
+ */
+
+ void (*query_send)(adns_query qu, struct timeval now);
+ /* Send the query to nameservers, and hook it into the appropriate queue.
+ * Normal behaviour is to call adns__query_send, but this can be overridden
+ * for special effects.
+ */
+} typeinfo;
+
+adns_status adns__ckl_hostname(adns_state ads, adns_queryflags flags,
+ union checklabel_state *cls,
+ qcontext *ctx, int labnum,
+ const char *label, int lablen);
+ /* implemented in query.c, used by types.c as default
+ * and as part of implementation for some fancier types
+ * doesn't require any state */
+
+typedef struct allocnode {
+ struct allocnode *next, *back;
+ size_t sz;
+} allocnode;
+
+union maxalign {
+ byte d[1];
+ struct in_addr ia;
+ long l;
+ void *p;
+ void (*fp)(void);
+ union maxalign *up;
+} data;
+
struct adns__query {
- /* FIXME: make sure this is all init'd properly */
- enum { query_udp, query_tcpwait, query_tcpsent, query_child, query_done } state;
+ adns_state ads;
+ enum { query_tosend, query_tcpw, query_childw, query_done } state;
adns_query back, next, parent;
struct { adns_query head, tail; } children;
struct { adns_query back, next; } siblings;
- adns_rrtype type;
- vbuf answer;
- int id, flags, udpretries;
+ struct { allocnode *head, *tail; } allocations;
+ int interim_allocd, preserved_allocd;
+ void *final_allocspace;
+
+ const typeinfo *typei;
+ byte *query_dgram;
+ int query_dglen;
+
+ vbuf vb;
+ /* General-purpose messing-about buffer.
+ * Wherever a `big' interface is crossed, this may be corrupted/changed
+ * unless otherwise specified.
+ */
+
+ adns_answer *answer;
+ /* This is allocated when a query is submitted, to avoid being unable
+ * to relate errors to queries if we run out of memory. During
+ * query processing status, rrs is 0. cname is set if
+ * 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, retries;
int udpnextserver;
- unsigned long udpsent, tcpfailed; /* bitmap indexed by server */
+ unsigned long udpsent; /* bitmap indexed by server */
struct timeval timeout;
- byte *querymsg;
- int querylen;
- qcontext context;
- char owner[1];
- /* After the owner name and nul comes the query message, pointed to by querymsg */
+ time_t expires; /* Earliest expiry time of any record we used. */
+
+ qcontext ctx;
/* Possible states:
*
- * state Queue child id answer nextudpserver sentudp failedtcp
+ * state Queue child id nextudpserver udpsent tcpfailed
*
- * udp NONE null >=0 null 0 zero zero
- * udp timew null >=0 null any nonzero zero
- * udp NONE null >=0 null any nonzero zero
+ * tosend NONE null >=0 0 zero zero
+ * tosend udpw null >=0 any nonzero zero
+ * tosend NONE null >=0 any nonzero zero
*
- * tcpwait timew null >=0 null irrelevant zero any
- * tcpsent timew null >=0 null irrelevant zero any
+ * tcpw tcpw null >=0 irrelevant any any
*
- * child childw set >=0 partial irrelevant irrelevant irrelevant
- * done output null -1 set/null irrelevant irrelevant irrelevant
+ * 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.
+ * Queries in state tcpw/tcpw have been sent (or are in the to-send buffer)
+ * iff the tcp connection is in state server_ok.
*
* +------------------------+
- * START -----> | udp/NONE |
+ * START -----> | tosend/NONE |
* +------------------------+
* / |\ \
* too big for UDP / UDP timeout \ \ send via UDP
- * do this ASAP! / more retries \ \ do this ASAP!
- * |_ desired \ _|
- * +---------------+ +-----------+
- * | tcpwait/timew | ____ | udp/timew |
- * +---------------+ \ +-----------+
- * | ^ | | |
- * TCP conn'd; | | TCP died | | |
- * send via TCP | | more | UDP timeout | |
- * do this ASAP! | | servers | no more | |
- * v | to try | retries | |
- * +---------------+ | desired | |
- * | tcpsent/timew | ____ | | |
- * +---------------+ \| | |
- * \ \ TCP died | TCP | |
- * \ \ no more | timeout / |
- * \ \ servers | / |
- * \ \ to try | / |
- * got \ \ v |_ / got
+ * send via TCP / more retries \ \
+ * when conn'd / desired \ \
+ * | | |
+ * v | v
+ * +-----------+ +-------------+
+ * | tcpw/tcpw | ________ | tosend/udpw |
+ * +-----------+ \ +-------------+
+ * | | | UDP timeout | |
+ * | | | no more | |
+ * | | | retries | |
+ * \ | TCP died | desired | |
+ * \ \ no more | | |
+ * \ \ servers | TCP / |
+ * \ \ to try | timeout / |
+ * got \ \ v |_ | got
* reply \ _| +------------------+ / reply
* \ | done/output FAIL | /
* \ +------------------+ /
* need child query/ies / \ no child query
* / \
* |_ _|
- * +--------------+ +----------------+
- * | child/childw | ----------------> | done/output OK |
- * +--------------+ children done +----------------+
+ * +---------------+ +----------------+
+ * | childw/childw | ----------------> | done/output OK |
+ * +---------------+ children done +----------------+
*/
};
+struct query_queue { adns_query head, tail; };
+
+#define MAXUDP 2
+
struct adns__state {
adns_initflags iflags;
- FILE *diagfile;
- struct { adns_query head, tail; } timew, childw, output;
- int nextid, udpsocket, tcpsocket;
- vbuf rqbuf, tcpsend, tcprecv;
- int nservers, tcpserver;
- enum adns__tcpstate { server_disconnected, server_connecting, server_ok } tcpstate;
+ adns_logcallbackfn *logfn;
+ void *logfndata;
+ int configerrno;
+ struct query_queue udpw, tcpw, childw, output;
+ adns_query forallnext;
+ int nextid, tcpsocket;
+ struct udpsocket { int af; int fd; } udpsocket[MAXUDP];
+ int nudp;
+ vbuf tcpsend, tcprecv;
+ int nservers, nsortlist, nsearchlist, searchndots, tcpserver, tcprecv_skip;
+ enum adns__tcpstate {
+ server_disconnected, server_connecting,
+ server_ok, server_broken
+ } tcpstate;
struct timeval tcptimeout;
- struct server {
- struct in_addr addr;
- } servers[MAXSERVERS];
+ /* This will have tv_sec==0 if it is not valid. It will always be
+ * valid if tcpstate _connecting. When _ok, it will be nonzero if
+ * we are idle (ie, tcpw queue is empty), in which case it is the
+ * absolute time when we will close the connection.
+ */
+ struct sigaction stdsigpipe;
+ sigset_t stdsigmask;
+ struct pollfd pollfds_buf[MAX_POLLFDS];
+ adns_rr_addr servers[MAXSERVERS];
+ struct sortlist {
+ int af;
+ union gen_addr base, mask;
+ } sortlist[MAXSORTLIST];
+ char **searchlist;
+ unsigned short rand48xsubi[3];
};
+/* From addrfam.c: */
+
+extern int adns__af_supported_p(int af);
+/* Return nonzero if the address family af known to the library and supported
+ * by the other addrfam operations. Note that the other operations will
+ * abort on an unrecognized address family rather than returning an error
+ * code.
+ */
+
+extern int adns__genaddr_equal_p(int af, const union gen_addr *a,
+ int bf, const void *b);
+/* b should point to a `struct in_addr' or equivalent for the address family
+ * bf. Returns nonzero if the two addresses are equal.
+ */
+
+extern int adns__sockaddr_equal_p(const struct sockaddr *sa,
+ const struct sockaddr *sb);
+/* Return nonzero if the two socket addresses are equal (in all significant
+ * respects).
+ */
+
+extern int adns__addr_width(int af);
+/* Return the width of addresses of family af, in bits. */
+
+extern void adns__prefix_mask(int af, int len, union gen_addr *mask_r);
+/* Store in mask_r an address mask for address family af, whose first len
+ * bits are set and the remainder are clear. This is what you want for
+ * converting a prefix length into a netmask.
+ */
+
+extern int adns__guess_prefix_length(int af, const union gen_addr *addr);
+/* Given a network base address, guess the appropriate prefix length based on
+ * the appropriate rules for the address family (e.g., for IPv4, this uses
+ * the old address classes).
+ */
+
+extern int adns__addr_match_p(int addraf, const union gen_addr *addr,
+ int netaf, const union gen_addr *base,
+ const union gen_addr *mask);
+/* Given an address af (with family addraf) and a network (with family netaf,
+ * base address base, and netmask mask), return nonzero if the address lies
+ * within the network.
+ */
+
+extern void adns__sockaddr_extract(const struct sockaddr *sa,
+ union gen_addr *a_r, int *port_r);
+/* Extract fields from the socket address, filling in *a_r and *port_r with
+ * the address and (integer, host byte-order) port number, respectively.
+ * Either (or, pointlessly, both) of a_r and port_r may be null to mean
+ * `don't care'.
+ */
+
+extern void adns__sockaddr_inject(const union gen_addr *a, int port,
+ struct sockaddr *sa);
+/* Inject fields into the socket adress sa. If a is not null, copy the
+ * address in; if port is not -1, then copy the port (converting from host
+ * byte-order). Assumes that sa->sa_family is already set correctly.
+ */
+
+char *adns__sockaddr_ntoa(const struct sockaddr *sa, char *buf);
+/* Convert sa to a string, and write it to buf, which must be at least
+ * ADNS_ADDR2TEXT_BUFLEN bytes long (unchecked). Return buf; can't fail.
+ */
+
+extern int adns__make_reverse_domain(const struct sockaddr *sa,
+ const char *zone,
+ char **buf_io, size_t bufsz,
+ char **buf_free_r);
+/* Construct a reverse domain string, given a socket address and a parent
+ * zone. If zone is null, then use the standard reverse-lookup zone for the
+ * address family. If the length of the resulting string is no larger than
+ * bufsz, then the result is stored starting at *buf_io; otherwise a new
+ * buffer is allocated is used, and a pointer to it is stored in both *buf_io
+ * and *buf_free_r (the latter of which should be null on entry). If
+ * something goes wrong, then an errno value is returned: ENOSYS if the
+ * address family of sa isn't recognized, or ENOMEM if the attempt to
+ * allocate an output buffer failed.
+ */
+
+extern int adns__revparse_label(struct revparse_state *rps, int labnum,
+ const char *label, int lablen);
+/* Parse a label in a reverse-domain name, given its index labnum (starting
+ * from zero), a pointer to its contents (which need not be null-terminated),
+ * and its length. The state in *rps is initialized implicitly when labnum
+ * is zero.
+ *
+ * Returns zero if the parse was successful, nonzero if the domain name is
+ * definitely invalid and the parse must be abandoned.
+ */
+
+extern int adns__revparse_done(struct revparse_state *rps, int nlabels,
+ adns_rrtype *rrtype_r, struct af_addr *addr_r);
+/* Finishes parsing a reverse-domain name, given the total number of labels
+ * in the name. On success, fills in the address in *addr_r, and the forward
+ * query type in *rrtype_r (because that turns out to be useful). Returns
+ * nonzero if the parse must be abandoned.
+ */
+
/* From setup.c: */
+int adns__setnonblock(adns_state ads, int fd); /* => errno value */
+
+/* From general.c: */
+
+void adns__vlprintf(adns_state ads, const char *fmt, va_list al);
+void adns__lprintf(adns_state ads, const char *fmt,
+ ...) PRINTFFORMAT(2,3);
+
void adns__vdiag(adns_state ads, const char *pfx, adns_initflags prevent,
- int serv, const char *fmt, va_list al);
-void adns__debug(adns_state ads, int serv, const char *fmt, ...) PRINTFFORMAT(3,4);
-void adns__warn(adns_state ads, int serv, const char *fmt, ...) PRINTFFORMAT(3,4);
-void adns__diag(adns_state ads, int serv, const char *fmt, ...) PRINTFFORMAT(3,4);
+ int serv, adns_query qu, const char *fmt, va_list al);
+
+void adns__debug(adns_state ads, int serv, adns_query qu,
+ const char *fmt, ...) PRINTFFORMAT(4,5);
+void adns__warn(adns_state ads, int serv, adns_query qu,
+ const char *fmt, ...) PRINTFFORMAT(4,5);
+void adns__diag(adns_state ads, int serv, adns_query qu,
+ const char *fmt, ...) PRINTFFORMAT(4,5);
int adns__vbuf_ensure(vbuf *vb, int want);
+int adns__vbuf_appendstr(vbuf *vb, const char *data); /* doesn't include nul */
int adns__vbuf_append(vbuf *vb, const byte *data, int len);
/* 1=>success, 0=>realloc failed */
void adns__vbuf_appendq(vbuf *vb, const byte *data, int len);
void adns__vbuf_init(vbuf *vb);
+void adns__vbuf_free(vbuf *vb);
+
+const char *adns__diag_domain(adns_state ads, int serv, adns_query qu,
+ vbuf *vb,
+ const byte *dgram, int dglen, int cbyte);
+/* Unpicks a domain in a datagram and returns a string suitable for
+ * printing it as. Never fails - if an error occurs, it will
+ * return some kind of string describing the error.
+ *
+ * serv may be -1 and qu may be 0. vb must have been initialised,
+ * and will be left in an arbitrary consistent state.
+ *
+ * Returns either vb->buf, or a pointer to a string literal. Do not modify
+ * vb before using the return value.
+ */
+
+int adns__getrrsz_default(const typeinfo *typei, adns_rrtype type);
+/* Default function for the `getrrsz' type hook; returns the `fixed_rrsz'
+ * value from the typeinfo entry.
+ */
+
+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, since the old signal mask
+ * is stored in the adns structure.
+ */
+
+/* From transmit.c: */
+
+adns_status adns__mkquery(adns_state ads, vbuf *vb, int *id_r,
+ const char *owner, int ol,
+ const typeinfo *typei, adns_rrtype type,
+ adns_queryflags flags);
+/* 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,
+ adns_rrtype type, adns_queryflags flags);
+/* Same as adns__mkquery, but takes the owner domain from an existing datagram.
+ * That domain must be correct and untruncated.
+ */
+
+void adns__querysend_tcp(adns_query qu, struct timeval now);
+/* Query must be in state tcpw/tcpw; it will be sent if possible and
+ * no further processing can be done on it for now. The connection
+ * might be broken, but no reconnect will be attempted.
+ */
+
+struct udpsocket *adns__udpsocket_by_af(adns_state ads, int af);
+/* Find the UDP socket structure in ads which has the given address family.
+ * Return null if there isn't one.
+ *
+ * This is used during initialization, so ads is only partially filled in.
+ * The requirements are that nudp is set, and that udpsocket[i].af are
+ * defined for 0<=i<nudp.
+ */
+
+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.
+ */
-int adns__setnonblock(adns_state ads, int fd); /* => errno value */
+/* From query.c: */
-/* From submit.c: */
+adns_status adns__internal_submit(adns_state ads, adns_query *query_r,
+ adns_query parent,
+ const typeinfo *typei, adns_rrtype type,
+ vbuf *qumsg_vb, int id,
+ adns_queryflags flags, struct timeval now,
+ 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 query datagram should already have been assembled in qumsg_vb;
+ * 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).
+ *
+ * *ctx is copied byte-for-byte into the query. Before doing this, its tinfo
+ * field may be modified by type hooks.
+ *
+ * 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.
+ *
+ * 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 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.
+ *
+ * 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);
+/* 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__free_interim(adns_query qu, void *p);
+/* Forget about a block allocated by adns__alloc_interim.
+ */
+
+void *adns__alloc_mine(adns_query qu, size_t sz);
+/* Like _interim, but does not record the length for later
+ * copying into the answer. This just ensures that the memory
+ * will be freed when we're done with the query.
+ */
+
+void *adns__alloc_final(adns_query qu, size_t sz);
+/* Cannot fail, and cannot return 0.
+ */
+
+void adns__makefinal_block(adns_query qu, void **blpp, size_t sz);
+void adns__makefinal_str(adns_query qu, char **strp);
+
+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__cancel(adns_query qu);
+void adns__query_done(adns_query qu);
+void adns__query_fail(adns_query qu, adns_status stat);
+void adns__cancel_children(adns_query qu);
+
+void adns__returning(adns_state ads, adns_query qu);
+/* Must be called before returning from adns any time that we have
+ * progressed (including made, finished or destroyed) queries. */
-void adns__query_nomem(adns_state ads, adns_query qu);
-void adns__query_fail(adns_state ads, adns_query qu, adns_status stat);
+/* From reply.c: */
-/* From query.c: */
+void adns__procdgram(adns_state ads, const byte *dgram, int len,
+ int serv, int viatcp, struct timeval now);
+/* This function is allowed to cause new datagrams to be constructed
+ * and sent, or even new queries to be started. However,
+ * query-sending functions are not allowed to call any general event
+ * loop functions in case they accidentally call this.
+ *
+ * Ie, receiving functions may call sending functions.
+ * Sending functions may NOT call receiving functions.
+ */
-void adns__query_udp(adns_state ads, adns_query qu, struct timeval now);
-void adns__query_tcp(adns_state ads, adns_query qu, struct timeval now);
-adns_status adns__mkquery(adns_state ads, const char *owner, int ol, int id,
- adns_rrtype type, adns_queryflags flags);
+/* From types.c: */
-/* From reply.c: */
+const typeinfo *adns__findtype(adns_rrtype type);
+
+/* From parse.c: */
-void adns__procdgram(adns_state ads, const byte *dgram, int len, int serv);
+typedef struct {
+ adns_state ads;
+ adns_query qu;
+ int serv;
+ const byte *dgram;
+ int dglen, max, cbyte, namelen;
+ int *dmend_r;
+} findlabel_state;
+
+void adns__findlabel_start(findlabel_state *fls, adns_state ads,
+ int serv, adns_query qu,
+ const byte *dgram, int dglen, int max,
+ int dmbegin, int *dmend_rlater);
+/* Finds labels in a domain in a datagram.
+ *
+ * Call this routine first.
+ * dmend_rlater may be null. ads (and of course fls) may not be.
+ * serv may be -1, qu may be null - they are for error reporting.
+ */
+
+adns_status adns__findlabel_next(findlabel_state *fls,
+ int *lablen_r, int *labstart_r);
+/* Then, call this one repeatedly.
+ *
+ * It will return adns_s_ok if all is well, and tell you the length
+ * and start of successive labels. labstart_r may be null, but
+ * lablen_r must not be.
+ *
+ * After the last label, it will return with *lablen_r zero.
+ * Do not then call it again; instead, just throw away the findlabel_state.
+ *
+ * *dmend_rlater will have been set to point to the next part of
+ * the datagram after the label (or after the uncompressed part,
+ * if compression was used). *namelen_rlater will have been set
+ * to the length of the domain name (total length of labels plus
+ * 1 for each intervening dot).
+ *
+ * If the datagram appears to be truncated, *lablen_r will be -1.
+ * *dmend_rlater, *labstart_r and *namelen_r may contain garbage.
+ * Do not call _next again.
+ *
+ * There may also be errors, in which case *dmend_rlater,
+ * *namelen_rlater, *lablen_r and *labstart_r may contain garbage.
+ * Do not then call findlabel_next again.
+ */
+
+typedef enum {
+ pdf_quoteok= 0x001
+} parsedomain_flags;
+
+adns_status adns__parse_domain(adns_state ads, int serv, adns_query qu,
+ vbuf *vb, parsedomain_flags flags,
+ const byte *dgram, int dglen, int *cbyte_io,
+ int max);
+/* vb must already have been initialised; it will be reset if necessary.
+ * If there is truncation, vb->used will be set to 0; otherwise
+ * (if there is no error) vb will be null-terminated.
+ * If there is an error vb and *cbyte_io may be left indeterminate.
+ *
+ * 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, 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, 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);
+/* what and why may be both 0, or both non-0. */
+
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.
+ * 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);
+/* Call with care - might reentrantly cause queries to be completed! */
+
+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);
+
+void adns__timeouts(adns_state ads, int act,
+ struct timeval **tv_io, struct timeval *tvbuf,
+ struct timeval now);
+/* If act is !0, then this will also deal with the TCP connection
+ * if previous events broke it or require it to be connected.
+ */
+
+/* From check.c: */
+
+void adns__consistency(adns_state ads, adns_query qu, consistency_checks cc);
/* Useful static inline functions: */
-static inline void timevaladd(struct timeval *tv_io, long ms) {
- struct timeval tmp;
- assert(ms>=0);
- tmp= *tv_io;
- tmp.tv_usec += (ms%1000)*1000;
- tmp.tv_sec += ms/1000;
- if (tmp.tv_usec >= 1000) { tmp.tv_sec++; tmp.tv_usec -= 1000; }
- *tv_io= tmp;
+static inline int ctype_whitespace(int c) {
+ return c==' ' || c=='\n' || c=='\t';
}
-
-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');
+}
+static inline int ctype_822special(int c) {
+ return strchr("()<>@,;:\\\".[]",c) != 0;
+}
+static inline int ctype_domainunquoted(int c) {
+ return ctype_alpha(c) || ctype_digit(c) || (strchr("-_/+",c) != 0);
+}
+
+static inline int errno_resources(int e) { return e==ENOMEM || e==ENOBUFS; }
/* Useful macros */
-#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 back= 0; \
- (node)->part next= (list).tail; \
- if ((list).tail) (list).tail->part back= (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 MEM_ROUND(sz) \
+ (( ((sz)+sizeof(union maxalign)-1) / sizeof(union maxalign) ) \
+ * sizeof(union maxalign) )
+
+#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
~mdw / adns / blobdiff