#include <errno.h>
#include <limits.h>
#include <unistd.h>
+#include <inttypes.h>
+#include <stddef.h>
+#include <stdbool.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
+#include <net/if.h>
#include "internal.h"
* General address-family operations.
*/
-#define SIN(sa) ((struct sockaddr_in *)(sa))
-#define CSIN(sa) ((const struct sockaddr_in *)(sa))
-
-#define SIN6(sa) ((struct sockaddr_in6 *)(sa))
-#define CSIN6(sa) ((const struct sockaddr_in6 *)(sa))
-
-/* This gadget (thanks, Richard Kettlewell) makes sure that we handle the
- * same set of address families in each switch. */
-#define AF_CASES(pre) \
- case AF_INET: goto pre##_inet; \
- case AF_INET6: goto pre##_inet6
+#define SIN(cnst, sa) ((void)(sa)->sa_family, (cnst struct sockaddr_in *)(sa))
+#define SIN6(cnst, sa) ((void)(sa)->sa_family, (cnst struct sockaddr_in6 *)(sa))
+static void unknown_af(int af) NONRETURNING;
static void unknown_af(int af) {
fprintf(stderr, "ADNS INTERNAL: unknown address family %d\n", af);
abort();
}
-#define IN6_ADDR_EQUALP(a, b) \
- (!memcmp((a).s6_addr, (b).s6_addr, sizeof((a).s6_addr)))
-
-int adns__genaddr_equal_p(int af, const union gen_addr *a,
- int bf, const void *b) {
- const union gen_addr *bb= b;
- if (af != bf) return 0;
- switch (af) {
- AF_CASES(af);
- af_inet: return a->v4.s_addr == bb->v4.s_addr;
- af_inet6: return IN6_ADDR_EQUALP(a->v6, bb->v6);
- default: unknown_af(af); return -1;
+/*
+ * SOCKADDR_IN_IN6(CNST, struct sockaddr *sa, SIN, {
+ * // struct sockaddr_in *const SIN; // implicitly
+ * code for inet;
+ * }, {
+ * // struct sockaddr_in6 *const SIN6; // implicitly
+ * code for inet6;
+ * })
+ *
+ * SOCKADDR_IN_IN6_PAIR(CNST, struct sockaddr *sa, SINA,
+ * struct sockaddr *sb, SINB, {
+ * // struct sockaddr_in *const SINA; // implicitly
+ * // struct sockaddr_in *const SINB; // implicitly
+ * code for inet;
+ * },{
+ * // struct sockaddr_in6 *const SINA6; // implicitly
+ * // struct sockaddr_in6 *const SINB6; // implicitly
+ * code for inet6;
+ * });
+ *
+ * SOCKADDR_IN_IN6_OTHER(CNST, struct sockaddr *sa, SIN, { in }, { in6 }, {
+ * code for other address family
+ * })
+ *
+ * AF_IN_IN6_OTHER(af, { in }, { in6 }, { other })
+ *
+ * Executes the first or second block according to the AF in sa. CNST
+ * may be `const' or empty. For _PAIR, sa and sb must be same AF.
+ *
+ * All except _OTHER handle unknown AFs with unknown_af.
+ *
+ * Code blocks may not contain , outside parens.
+ */
+#define AF_IN_IN6_OTHER(af, for_inet, for_inet6, other) \
+ if ((af) == AF_INET) { \
+ for_inet \
+ } else if ((af) == AF_INET6) { \
+ for_inet6 \
+ } else { \
+ other \
}
+#define SOCKADDR_IN_IN6_OTHER(cnst, sa, sin, for_inet, for_inet6, other) \
+ AF_IN_IN6_OTHER((sa)->sa_family, { \
+ cnst struct sockaddr_in *const sin = SIN(cnst,(sa)); \
+ for_inet \
+ }, { \
+ cnst struct sockaddr_in6 *const sin##6 = SIN6(cnst,(sa)); \
+ for_inet6 \
+ }, \
+ other \
+ )
+#define SOCKADDR_IN_IN6(cnst, sa, sin, for_inet, for_inet6) \
+ SOCKADDR_IN_IN6_OTHER(cnst, sa, sin, for_inet, for_inet6, { \
+ unknown_af((sa)->sa_family); \
+ })
+#define SOCKADDR_IN_IN6_PAIR(cnst, sa, sina, sb, sinb, for_inet, for_inet6) \
+ do{ \
+ assert((sa)->sa_family == (sb)->sa_family); \
+ SOCKADDR_IN_IN6(cnst, sa, sina, { \
+ cnst struct sockaddr_in *const sinb = SIN(cnst,(sb)); \
+ for_inet \
+ }, { \
+ cnst struct sockaddr_in6 *const sinb##6 = SIN6(cnst,(sb)); \
+ for_inet6 \
+ }); \
+ }while(0)
+
+int adns__addrs_equal_raw(const struct sockaddr *a,
+ int bf, const void *b) {
+ if (a->sa_family != bf) return 0;
+
+ SOCKADDR_IN_IN6(const, a, sin, {
+ return sin->sin_addr.s_addr == ((const struct in_addr*)b)->s_addr;
+ }, {
+ return !memcmp(&sin6->sin6_addr, b, sizeof(struct in6_addr));
+ });
}
-int adns__sockaddr_equal_p(const struct sockaddr *sa,
- const struct sockaddr *sb) {
- if (sa->sa_family != sb->sa_family) return 0;
- switch (sa->sa_family) {
- AF_CASES(af);
- af_inet: {
- const struct sockaddr_in *sina= CSIN(sa), *sinb= CSIN(sb);
- return (sina->sin_addr.s_addr == sinb->sin_addr.s_addr &&
- sina->sin_port == sinb->sin_port);
- }
- af_inet6: {
- /* Don't check the flowlabel. That's apparently useful for routing
- * performance, but doesn't affect the address in any important
- * respect. */
- const struct sockaddr_in6 *sin6a= CSIN6(sa), *sin6b= CSIN6(sb);
- return (IN6_ADDR_EQUALP(sin6a->sin6_addr, sin6b->sin6_addr) &&
- sin6a->sin6_port == sin6b->sin6_port &&
- sin6a->sin6_scope_id == sin6b->sin6_scope_id);
- }
- default:
- unknown_af(sa->sa_family);
- return -1;
- }
+int adns__addrs_equal(const adns_sockaddr *a, const adns_sockaddr *b) {
+ return adns__addrs_equal_raw(&a->sa, b->sa.sa_family,
+ adns__sockaddr_addr(&b->sa));
+}
+
+int adns__sockaddrs_equal(const struct sockaddr *sa,
+ const struct sockaddr *sb) {
+ if (!adns__addrs_equal_raw(sa, sb->sa_family, adns__sockaddr_addr(sb)))
+ return 0;
+ SOCKADDR_IN_IN6_PAIR(const, sa, sina, sb, sinb, {
+ return sina->sin_port == sinb->sin_port;
+ }, {
+ return sina6->sin6_port == sinb6->sin6_port &&
+ sina6->sin6_scope_id == sinb6->sin6_scope_id;
+ });
}
int adns__addr_width(int af) {
- switch (af) {
- AF_CASES(af);
- af_inet: return 32;
- af_inet6: return 128;
- default: unknown_af(af); return -1;
- }
+ AF_IN_IN6_OTHER(af, {
+ return 32;
+ }, {
+ return 128;
+ }, {
+ unknown_af(af);
+ });
}
-void adns__prefix_mask(int af, int len, union gen_addr *mask_r) {
- switch (af) {
- AF_CASES(af);
- af_inet:
- assert(len <= 32);
- mask_r->v4.s_addr= htonl(!len ? 0 : 0xffffffff << (32-len));
- break;
- af_inet6: {
- int i= len/8, j= len%8;
- unsigned char *m= mask_r->v6.s6_addr;
- assert(len <= 128);
- memset(m, 0xff, i);
- if (j) m[i++]= (0xff << (8-j)) & 0xff;
- memset(m+i, 0, 16-i);
- } break;
- default:
- unknown_af(af);
- break;
- }
+void adns__prefix_mask(adns_sockaddr *sa, int len) {
+ SOCKADDR_IN_IN6(, &sa->sa, sin, {
+ assert(len <= 32);
+ sin->sin_addr.s_addr= htonl(!len ? 0 : 0xffffffff << (32-len));
+ }, {
+ int i= len/8;
+ int j= len%8;
+ unsigned char *m= sin6->sin6_addr.s6_addr;
+ assert(len <= 128);
+ memset(m, 0xff, i);
+ if (j) m[i++]= (0xff << (8-j)) & 0xff;
+ memset(m+i, 0, 16-i);
+ });
}
-int adns__guess_prefix_length(int af, const union gen_addr *addr) {
- switch (af) {
- AF_CASES(af);
- af_inet: {
- unsigned a= (ntohl(addr->v4.s_addr) >> 24) & 0xff;
- if (a < 128) return 8;
- else if (a < 192) return 16;
- else if (a < 224) return 24;
- else return -1;
- } break;
- af_inet6:
- return 64;
- default:
- unknown_af(af);
- return -1;
- }
+int adns__guess_prefix_length(const adns_sockaddr *sa) {
+ SOCKADDR_IN_IN6(const, &sa->sa, sin, {
+ unsigned a= (ntohl(sin->sin_addr.s_addr) >> 24) & 0xff;
+ if (a < 128) return 8;
+ else if (a < 192) return 16;
+ else if (a < 224) return 24;
+ else return -1;
+ }, {
+ (void)sin6;
+ return 64;
+ });
}
-int adns__addr_match_p(int addraf, const union gen_addr *addr,
- int netaf, const union gen_addr *base,
- const union gen_addr *mask)
+int adns__addr_matches(int af, const void *addr,
+ const adns_sockaddr *base, const adns_sockaddr *mask)
{
- if (addraf != netaf) return 0;
- switch (addraf) {
- AF_CASES(af);
- af_inet:
- return (addr->v4.s_addr & mask->v4.s_addr) == base->v4.s_addr;
- af_inet6: {
- int i;
- const char *a= addr->v6.s6_addr;
- const char *b= base->v6.s6_addr;
- const char *m= mask->v6.s6_addr;
- for (i = 0; i < 16; i++)
- if ((a[i] & m[i]) != b[i]) return 0;
- return 1;
- } break;
- default:
- unknown_af(addraf);
- return -1;
+ if (af != base->sa.sa_family) return 0;
+ SOCKADDR_IN_IN6_PAIR(const, &base->sa, sbase, &mask->sa, smask, {
+ const struct in_addr *v4 = addr;
+ return (v4->s_addr & smask->sin_addr.s_addr)
+ == sbase->sin_addr.s_addr;
+ }, {
+ int i;
+ const char *a= addr;
+ const char *b= sbase6->sin6_addr.s6_addr;
+ const char *m= smask6->sin6_addr.s6_addr;
+ for (i = 0; i < 16; i++)
+ if ((a[i] & m[i]) != b[i]) return 0;
+ return 1;
+ });
+}
+
+const void *adns__sockaddr_addr(const struct sockaddr *sa) {
+ SOCKADDR_IN_IN6(const, sa, sin, {
+ return &sin->sin_addr;
+ }, {
+ return &sin6->sin6_addr;
+ });
+}
+
+void adns__addr_inject(const void *a, adns_sockaddr *sa) {
+ SOCKADDR_IN_IN6( , &sa->sa, sin, {
+ memcpy(&sin->sin_addr, a, sizeof(sin->sin_addr));
+ }, {
+ memcpy(&sin6->sin6_addr, a, sizeof(sin6->sin6_addr));
+ });
+}
+
+/*
+ * addr2text and text2addr
+ */
+
+#define ADDRFAM_DEBUG
+#ifdef ADDRFAM_DEBUG
+static void af_debug_func(const char *fmt, ...) {
+ int esave= errno;
+ va_list al;
+ va_start(al,fmt);
+ vfprintf(stderr,fmt,al);
+ va_end(al);
+ errno= esave;
+}
+# define af_debug(fmt,...) \
+ (af_debug_func("%s: " fmt "\n", __func__, __VA_ARGS__))
+#else
+# define af_debug(fmt,...) ((void)("" fmt "", __VA_ARGS__))
+#endif
+
+static bool addrtext_our_errno(int e) {
+ return
+ e==EAFNOSUPPORT ||
+ e==EINVAL ||
+ e==ENOSPC ||
+ e==ENOSYS;
+}
+
+static bool addrtext_scope_use_ifname(const struct sockaddr *sa) {
+ const struct in6_addr *in6= &SIN6(const,sa)->sin6_addr;
+ return
+ IN6_IS_ADDR_LINKLOCAL(in6) ||
+ IN6_IS_ADDR_MC_LINKLOCAL(in6);
+}
+
+int adns_text2addr(const char *text, uint16_t port, adns_queryflags flags,
+ struct sockaddr *sa, socklen_t *salen_io) {
+ int af;
+ char copybuf[INET6_ADDRSTRLEN];
+ const char *parse=text;
+ const char *scopestr=0;
+ socklen_t needlen;
+ void *dst;
+ uint16_t *portp;
+
+#define INVAL(how) do{ \
+ af_debug("invalid: %s: `%s'", how, text); \
+ return EINVAL; \
+}while(0)
+
+#define AFCORE(INETx,SINx,sinx) \
+ af= AF_##INETx; \
+ dst = &SINx(,sa)->sinx##_addr; \
+ portp = &SINx(,sa)->sinx##_port; \
+ needlen= sizeof(*SINx(,sa));
+
+ if (!strchr(text, ':')) { /* INET */
+
+ AFCORE(INET,SIN,sin);
+
+ } else { /* INET6 */
+
+ AFCORE(INET6,SIN6,sin6);
+
+ const char *percent= strchr(text, '%');
+ if (percent) {
+ ptrdiff_t lhslen = percent - text;
+ if (lhslen >= INET6_ADDRSTRLEN) INVAL("scoped addr lhs too long");
+ memcpy(copybuf, text, lhslen);
+ copybuf[lhslen]= 0;
+
+ parse= copybuf;
+ scopestr= percent+1;
+
+ af_debug("will parse scoped addr `%s' %% `%s'", parse, scopestr);
+ }
+
}
+
+#undef AFCORE
+
+ if (scopestr && (flags & adns_qf_addrlit_scope_forbid))
+ INVAL("scoped addr but _scope_forbid");
+
+ if (*salen_io < needlen) {
+ *salen_io = needlen;
+ return ENOSPC;
+ }
+
+ memset(sa, 0, needlen);
+
+ sa->sa_family= af;
+ *portp = htons(port);
+
+ if (af == AF_INET && !(flags & adns_qf_addrlit_ipv4_quadonly)) {
+ /* we have to use inet_aton to deal with non-dotted-quad literals */
+ int r= inet_aton(parse,&SIN(,sa)->sin_addr);
+ if (!r) INVAL("inet_aton rejected");
+ } else {
+ int r= inet_pton(af,parse,dst);
+ if (!r) INVAL("inet_pton rejected");
+ assert(r>0);
+ }
+
+ if (scopestr) {
+ errno=0;
+ char *ep;
+ unsigned long scope= strtoul(scopestr,&ep,10);
+ if (errno==ERANGE) INVAL("numeric scope id too large for unsigned long");
+ assert(!errno);
+ if (!*ep) {
+ if (scope > ~(uint32_t)0)
+ INVAL("numeric scope id too large for uint32_t");
+ } else { /* !!*ep */
+ if (flags & adns_qf_addrlit_scope_numeric)
+ INVAL("non-numeric scope but _scope_numeric");
+ if (!addrtext_scope_use_ifname(sa)) {
+ af_debug("cannot convert non-numeric scope"
+ " in non-link-local addr `%s'", text);
+ return ENOSYS;
+ }
+ errno= 0;
+ scope= if_nametoindex(scopestr);
+ if (!scope) {
+ /* RFC3493 says "No errors are defined". It's not clear
+ * whether that is supposed to mean if_nametoindex "can't
+ * fail" (other than by the supplied name not being that of an
+ * interface) which seems unrealistic, or that it conflates
+ * all its errors together by failing to set errno, or simply
+ * that they didn't bother to document the errors.
+ *
+ * glibc, FreeBSD and OpenBSD all set errno (to ENXIO when
+ * appropriate). See Debian bug #749349.
+ *
+ * We attempt to deal with this by clearing errno to start
+ * with, and then perhaps mapping the results. */
+ af_debug("if_nametoindex rejected scope name (errno=%s)",
+ strerror(errno));
+ if (errno==0) {
+ return ENXIO;
+ } else if (addrtext_our_errno(errno)) {
+ /* we use these for other purposes, urgh. */
+ perror("adns: adns_text2addr: if_nametoindex"
+ " failed with unexpected error");
+ return EIO;
+ } else {
+ return errno;
+ }
+ } else { /* ix>0 */
+ if (scope > ~(uint32_t)0) {
+ fprintf(stderr,"adns: adns_text2addr: if_nametoindex"
+ " returned an interface index >=2^32 which will not fit"
+ " in sockaddr_in6.sin6_scope_id");
+ return EIO;
+ }
+ }
+ } /* else; !!*ep */
+
+ SIN6(,sa)->sin6_scope_id= scope;
+ } /* if (scopestr) */
+
+ *salen_io = needlen;
+ return 0;
}
-void adns__sockaddr_extract(const struct sockaddr *sa,
- union gen_addr *a_r, int *port_r) {
- switch (sa->sa_family) {
- AF_CASES(af);
- af_inet: {
- const struct sockaddr_in *sin = CSIN(sa);
- if (port_r) *port_r= ntohs(sin->sin_port);
- if (a_r) a_r->v4= sin->sin_addr;
- break;
+int adns_addr2text(const struct sockaddr *sa, adns_queryflags flags,
+ char *buffer, int *buflen_io, int *port_r) {
+ const void *src;
+ int port;
+
+ if (*buflen_io < ADNS_ADDR2TEXT_BUFLEN) {
+ *buflen_io = ADNS_ADDR2TEXT_BUFLEN;
+ return ENOSPC;
}
- af_inet6: {
- const struct sockaddr_in6 *sin6 = CSIN6(sa);
- if (port_r) *port_r= ntohs(sin6->sin6_port);
- if (a_r) a_r->v6= sin6->sin6_addr;
- break;
+
+ SOCKADDR_IN_IN6_OTHER(const, sa, sin, {
+ src= &sin->sin_addr; port= sin->sin_port;
+ }, {
+ src= &sin6->sin6_addr; port= sin6->sin6_port;
+ }, {
+ return EAFNOSUPPORT;
+ });
+
+ const char *ok= inet_ntop(sa->sa_family, src, buffer, *buflen_io);
+ assert(ok);
+
+ if (sa->sa_family == AF_INET6) {
+ uint32_t scope = SIN6(const,sa)->sin6_scope_id;
+ if (scope) {
+ if (flags & adns_qf_addrlit_scope_forbid)
+ return EINVAL;
+ int scopeoffset = strlen(buffer);
+ int remain = *buflen_io - scopeoffset;
+ char *scopeptr = buffer + scopeoffset;
+ assert(remain >= IF_NAMESIZE+1/*%*/);
+ *scopeptr++= '%'; remain--;
+ bool parsedname = 0;
+ af_debug("will print scoped addr `%.*s' %% %"PRIu32"",
+ scopeoffset,buffer, scope);
+ if (scope <= UINT_MAX /* so we can pass it to if_indextoname */
+ && !(flags & adns_qf_addrlit_scope_numeric)
+ && addrtext_scope_use_ifname(sa)) {
+ parsedname = if_indextoname(scope, scopeptr);
+ if (!parsedname) {
+ af_debug("if_indextoname rejected scope (errno=%s)",
+ strerror(errno));
+ if (errno==ENXIO) {
+ /* fair enough, show it as a number then */
+ } else if (addrtext_our_errno(errno)) {
+ /* we use these for other purposes, urgh. */
+ perror("adns: adns_addr2text: if_indextoname"
+ " failed with unexpected error");
+ return EIO;
+ } else {
+ return errno;
+ }
+ }
+ }
+ if (!parsedname) {
+ int r = snprintf(scopeptr, remain,
+ "%"PRIu32"", scope);
+ assert(r < *buflen_io - scopeoffset);
+ }
+ af_debug("printed scoped addr `%s'", buffer);
+ }
}
- default:
- unknown_af(sa->sa_family);
+
+ if (port_r) *port_r= ntohs(port);
+ return 0;
+}
+
+char *adns__sockaddr_ntoa(const struct sockaddr *sa, char *buf) {
+ int err;
+ int len= ADNS_ADDR2TEXT_BUFLEN;
+
+ err= adns_addr2text(sa, 0, buf, &len, 0);
+ if (err == EIO)
+ err= adns_addr2text(sa, adns_qf_addrlit_scope_numeric, buf, &len, 0);
+ assert(!err);
+ return buf;
+}
+
+/*
+ * Reverse-domain parsing and construction.
+ */
+
+int adns__make_reverse_domain(const struct sockaddr *sa, const char *zone,
+ char **buf_io, size_t bufsz,
+ char **buf_free_r) {
+ size_t req;
+ char *p;
+ unsigned c, y;
+ unsigned long aa;
+ const unsigned char *ap;
+ int i, j;
+
+ AF_IN_IN6_OTHER(sa->sa_family, {
+ req= 4 * 4;
+ if (!zone) zone= "in-addr.arpa";
+ }, {
+ req = 2 * 32;
+ if (!zone) zone= "ip6.arpa";
+ }, {
+ return ENOSYS;
+ });
+
+ req += strlen(zone) + 1;
+ if (req <= bufsz)
+ p= *buf_io;
+ else {
+ p= malloc(req); if (!p) return errno;
+ *buf_free_r = p;
}
+
+ *buf_io= p;
+ SOCKADDR_IN_IN6(const, sa, sin, {
+ aa= ntohl(sin->sin_addr.s_addr);
+ for (i=0; i<4; i++) {
+ p += sprintf(p, "%d", (int)(aa & 0xff));
+ *p++= '.';
+ aa >>= 8;
+ }
+ }, {
+ ap= sin6->sin6_addr.s6_addr + 16;
+ for (i=0; i<16; i++) {
+ c= *--ap;
+ for (j=0; j<2; j++) {
+ y= c & 0xf;
+ *p++= (y < 10) ? y + '0' : y - 10 + 'a';
+ c >>= 4;
+ *p++= '.';
+ }
+ }
+ });
+
+ strcpy(p, zone);
+ return 0;
}
-void adns__sockaddr_inject(const union gen_addr *a, int port,
- struct sockaddr *sa) {
- switch (sa->sa_family) {
- AF_CASES(af);
- af_inet: {
- struct sockaddr_in *sin = SIN(sa);
- if (port != -1) sin->sin_port= htons(port);
- if (a) sin->sin_addr= a->v4;
- break;
+
+static int inet_rev_parsecomp(const char *p, size_t n) {
+ int i= 0;
+ if (n > 3) return -1;
+
+ while (n--) {
+ if ('0' <= *p && *p <= '9') i= 10*i + *p++ - '0';
+ else return -1;
}
- af_inet6: {
- struct sockaddr_in6 *sin6 = SIN6(sa);
- if (port != -1) sin6->sin6_port= htons(port);
- if (a) sin6->sin6_addr= a->v6;
- break;
+ return i;
+}
+
+static void inet_rev_mkaddr(adns_sockaddr *addr, const byte *ipv) {
+ struct in_addr *v4 = &addr->inet.sin_addr;
+ v4->s_addr= htonl((ipv[3]<<24) | (ipv[2]<<16) |
+ (ipv[1]<<8) | (ipv[0]));
+}
+
+static int inet6_rev_parsecomp(const char *p, size_t n) {
+ if (n != 1) return -1;
+ else if ('0' <= *p && *p <= '9') return *p - '0';
+ else if ('a' <= *p && *p <= 'f') return *p - 'a' + 10;
+ else if ('A' <= *p && *p <= 'F') return *p - 'a' + 10;
+ else return -1;
+}
+
+static void inet6_rev_mkaddr(adns_sockaddr *addr, const byte *ipv) {
+ struct in6_addr *v6 = &addr->inet6.sin6_addr;
+ unsigned char *a= v6->s6_addr;
+ int i;
+
+ for (i=0; i<16; i++)
+ a[i]= (ipv[31-2*i] << 4) | (ipv[30-2*i] << 0);
+}
+
+static const struct revparse_domain {
+ int af; /* address family */
+ int nrevlab; /* n of reverse-address labels */
+ adns_rrtype rrtype; /* forward-lookup type */
+
+ int (*rev_parsecomp)(const char *p, size_t n);
+ /* parse a single component from a label; return the integer value, or -1
+ * if it was unintelligible.
+ */
+
+ void (*rev_mkaddr)(adns_sockaddr *addr, const byte *ipv);
+ /* write out the parsed protocol address from a vector of parsed components */
+
+ const char *const tail[3]; /* tail label names */
+} revparse_domains[NREVDOMAINS] = {
+ { AF_INET, 4, adns_r_a, inet_rev_parsecomp, inet_rev_mkaddr,
+ { DNS_INADDR_ARPA, 0 } },
+ { AF_INET6, 32, adns_r_aaaa, inet6_rev_parsecomp, inet6_rev_mkaddr,
+ { DNS_IP6_ARPA, 0 } },
+};
+
+#define REVDOMAIN_MAP(rps, labnum) \
+ ((labnum) ? (rps)->map : (1 << NREVDOMAINS) - 1)
+
+bool adns__revparse_label(struct revparse_state *rps, int labnum,
+ const char *dgram, int labstart, int lablen) {
+ const char *label = dgram+labstart;
+ unsigned f= REVDOMAIN_MAP(rps, labnum);
+ const struct revparse_domain *rpd;
+ const char *tp;
+ unsigned d;
+ int i, ac;
+
+ for (rpd=revparse_domains, i=0, d=1; i<NREVDOMAINS; rpd++, i++, d <<= 1) {
+ if (!(f & d)) continue;
+ if (labnum >= rpd->nrevlab) {
+ tp = rpd->tail[labnum - rpd->nrevlab];
+ if (!tp || strncmp(label, tp, lablen) != 0 || tp[lablen])
+ goto mismatch;
+ } else {
+ ac= rpd->rev_parsecomp(label, lablen);
+ if (ac < 0) goto mismatch;
+ assert(labnum < sizeof(rps->ipv[i]));
+ rps->ipv[i][labnum]= ac;
+ }
+ continue;
+
+ mismatch:
+ f &= ~d;
+ if (!f) return 0;
}
- default:
- unknown_af(sa->sa_family);
+
+ rps->map= f;
+ return 1;
+}
+
+bool adns__revparse_done(struct revparse_state *rps,
+ const char *dgram, int nlabels,
+ adns_rrtype *rrtype_r, adns_sockaddr *addr_r) {
+ unsigned f= REVDOMAIN_MAP(rps, nlabels);
+ const struct revparse_domain *rpd;
+ unsigned d;
+ int i, found= -1;
+
+ for (rpd=revparse_domains, i=0, d=1; i<NREVDOMAINS; rpd++, i++, d <<= 1) {
+ if (!(f & d)) continue;
+ if (nlabels >= rpd->nrevlab && !rpd->tail[nlabels - rpd->nrevlab])
+ { found = i; continue; }
+ f &= ~d;
+ if (!f) return 0;
}
+ assert(found >= 0); assert(f == (1 << found));
+
+ rpd= &revparse_domains[found];
+ *rrtype_r= rpd->rrtype;
+ addr_r->sa.sa_family= rpd->af;
+ rpd->rev_mkaddr(addr_r, rps->ipv[found]);
+ return 1;
}