X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=adns.git;a=blobdiff_plain;f=src%2Finternal.h;h=4fd6ee802fb622f1586a2428cbcfd2e4f7f0e131;hp=b8f881d0d8bff79ae32f94dd122120b9afbcc2a7;hb=07c3d3e2ca60a3dba7843ebeccc3dc06f3c8ce5d;hpb=4bec51a44bf61bca32e7b947f20b1e7d0f971b94 diff --git a/src/internal.h b/src/internal.h index b8f881d..4fd6ee8 100644 --- a/src/internal.h +++ b/src/internal.h @@ -1,136 +1,932 @@ -/**/ +/* + * 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 +#include "config.h" +typedef unsigned char byte; + +#include +#include +#include +#include +#include +#include +#include + #include #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 UDPMAXDGRAM 512 -#define NSPORT 53 +#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 */ -union adns__align { - adns_status status; - char *cp; - adns_rrtype type; - int int; - struct in_addr ia; - unsigned long ul; +typedef struct { + int used, avail; + byte *buf; +} vbuf; + +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; + 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 */ - adns_query back, next; - adns_query parent; + 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; + 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; - size_t ansalloc; ansused; - int id, flags, udpretries; /* udpretries==-1 => _f_usevc or too big for UDP */ - int nextudpserver, senttcpserver; - unsigned long sentudp; /* bitmap indexed by server */ + /* 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; /* bitmap indexed by server */ struct timeval timeout; - void *context; - unsigned char *querymsg; - int querylen; - char owner[1]; + time_t expires; /* Earliest expiry time of any record we used. */ + + qcontext ctx; + /* Possible states: - * Queue child id answer nextserver sentudp senttcp - * tosend null >=0 null any any any - * timew null >=0 null any at least 1 bit set any - * childw set >=0 partial any any any - * output null -1 set/null any any any + * + * state Queue child id nextudpserver udpsent tcpfailed + * + * tosend NONE null >=0 0 zero zero + * tosend udpw null >=0 any nonzero zero + * tosend NONE null >=0 any nonzero zero + * + * tcpw tcpw 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. + * 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 -----> | tosend/NONE | + * +------------------------+ + * / |\ \ + * too big for UDP / UDP timeout \ \ send via UDP + * 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 | / + * \ +------------------+ / + * \ / + * _| |_ + * (..... got reply ....) + * / \ + * need child query/ies / \ no child query + * / \ + * |_ _| + * +---------------+ +----------------+ + * | childw/childw | ----------------> | done/output OK | + * +---------------+ children done +----------------+ */ }; -struct adns__vbuf { - size_t used, avail; - unsigned char *buf; -}; +struct query_queue { adns_query head, tail; }; + +#define MAXUDP 2 struct adns__state { - /* FIXME: make sure this is all init'd properly */ adns_initflags iflags; - FILE *diagfile; - struct { adns_query head, tail; } tosend, timew, childw, output; - int nextid, udpsocket; - adns_vbuf rqbuf, tcpsend, tcprecv; - int nservers, tcpserver; - enum adns__tcpstate { server_disconnected, server_connecting, server_ok } tcpstate; - int tcpsocket; + 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: */ -void adns__vdiag(adns_state ads, adns_initflags prevent, const char *pfx, - 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 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); -/* From submit.c: */ +void adns__vdiag(adns_state ads, const char *pfx, adns_initflags prevent, + int serv, adns_query qu, const char *fmt, va_list al); -void adns__query_fail(adns_state ads, adns_query qu, adns_status stat); +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<=ivb). + * + * *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__query_done(adns_query qu); +void adns__query_fail(adns_query qu, adns_status stat); +void adns__cancel_children(adns_query qu); + +/* From reply.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. + */ + +/* From types.c: */ + +const typeinfo *adns__findtype(adns_rrtype type); + +/* From parse.c: */ + +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); -void adns__tcp_tryconnect(adns_state ads); +/* 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); + +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_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_PART(list,node) LIST_LINK_TAIL(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