Add generalized resolver routines.

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@931 ec53bebd-3082-4978-b11e-865c3cabbd6b

diff --git a/lib/roken/resolve.c b/lib/roken/resolve.c
new file mode 100644 (file)
index 0000000..92f04ba
--- /dev/null
+++ b/lib/roken/resolve.c
@@ -0,0 +1,281 @@
+/*
+ * Copyright (c) 1995, 1996 Kungliga Tekniska Högskolan (Royal Institute
+ * of Technology, Stockholm, Sweden).
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *      This product includes software developed by the Kungliga Tekniska
+ *      Högskolan and its contributors.
+ * 
+ * 4. Neither the name of the Institute nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "krb_locl.h"
+#include "resolve.h"
+
+RCSID("$Id$");
+
+#if defined(HAVE_RES_SEARCH) && defined(HAVE_DN_EXPAND)
+
+#define DECL(X) #X, T_##X
+
+static struct stot{
+    char *name;
+    int type;
+}stot[] = {
+    DECL(A),
+    DECL(NS),
+    DECL(CNAME),
+    DECL(PTR),
+    DECL(MX),
+    DECL(TXT),
+    DECL(AFSDB),
+    DECL(SRV),
+    NULL,      0
+};
+
+static int
+string_to_type(const char *name)
+{
+    struct stot *p = stot;
+    for(p = stot; p->name; p++)
+       if(strcasecmp(name, p->name) == 0)
+           return p->type;
+    return -1;
+}
+
+static char *
+type_to_string(int type)
+{
+    struct stot *p = stot;
+    for(p = stot; p->name; p++)
+       if(type == p->type)
+           return p->name;
+    return NULL;
+}
+
+void
+dns_free_data(struct dns_reply *r)
+{
+    struct resource_record *rr;
+    if(r->q.domain)
+       free(r->q.domain);
+    for(rr = r->head; rr;){
+       struct resource_record *tmp = rr;
+       if(rr->domain)
+           free(rr->domain);
+       if(rr->u.data)
+           free(rr->u.data);
+       rr = rr->next;
+       free(tmp);
+    }
+}
+
+static struct dns_reply*
+parse_reply(unsigned char *data, int len)
+{
+    unsigned char *p;
+    unsigned char host[128];
+    int status;
+    
+    struct dns_reply *r;
+    struct resource_record **rr;
+    
+    r = (struct dns_reply*)malloc(sizeof(struct dns_reply));
+    memset(r, 0, sizeof(struct dns_reply));
+
+    p = data;
+    memcpy(&r->h, p, sizeof(HEADER));
+    p += sizeof(HEADER);
+    status = dn_expand(data, data + len, p, host, sizeof(host));
+    if(status < 0){
+       dns_free_data(r);
+       return NULL;
+    }
+    r->q.domain = strdup((char*)host);
+    p += status;
+    r->q.type = (p[0] << 8 | p[1]);
+    p += 2;
+    r->q.class = (p[0] << 8 | p[1]);
+    p += 2;
+    rr = &r->head;
+    while(p < data + len){
+       int type, class, ttl, size, priority, weight, port;
+       status = dn_expand(data, data + len, p, host, sizeof(host));
+       if(status < 0){
+           dns_free_data(r);
+           return NULL;
+       }
+       p += status;
+       type = (p[0] << 8) | p[1];
+       p += 2;
+       class = (p[0] << 8) | p[1];
+       p += 2;
+       ttl = (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3];
+       p += 4;
+       size = (p[0] << 8) | p[1];
+       p += 2;
+       *rr = (struct resource_record*)malloc(sizeof(struct resource_record));
+       (*rr)->domain = strdup((char*)host);
+       (*rr)->type = type;
+       (*rr)->class = class;
+       (*rr)->ttl = ttl;
+       (*rr)->size = size;
+       switch(type){
+       case T_NS:
+       case T_CNAME:
+       case T_PTR:
+           status = dn_expand(data, data + len, p, host, sizeof(host));
+           if(status < 0){
+               dns_free_data(r);
+               return NULL;
+           }
+           (*rr)->u.txt = strdup((char*)host);
+           break;
+       case T_MX:
+       case T_AFSDB:{
+           struct mx_record *mx;
+           status = dn_expand(data, data + len, p + 2, host, sizeof(host));
+           if(status < 0){
+               dns_free_data(r);
+               return NULL;
+           }
+           (*rr)->u.mx = (struct mx_record*)malloc(sizeof(struct mx_record) + 
+                                                   strlen((char*)host));
+           (*rr)->u.mx->preference = (p[0] << 8) | p[1];
+           strcpy((*rr)->u.mx->domain, (char*)host);
+           break;
+       }
+       case T_SRV:{
+           struct srv_record *srv;
+           status = dn_expand(data, data + len, p + 6, host,
+                              sizeof((char*)host));
+           if(status < 0){
+               dns_free_data(r);
+               return NULL;
+           }
+           (*rr)->u.srv = 
+               (struct srv_record*)malloc(sizeof(struct srv_record) + 
+                                          strlen((char*)host));
+           (*rr)->u.srv->priority = (p[0] << 8) | p[1];
+           (*rr)->u.srv->weight = (p[2] << 8) | p[3];
+           (*rr)->u.srv->port = (p[4] << 8) | p[5];
+           strcpy((*rr)->u.srv->target, (char*)host);
+           break;
+       }
+       case T_TXT:{
+           (*rr)->u.txt = (char*)malloc(size + 1);
+           strncpy((*rr)->u.txt, (char*)p + 1, *p);
+           (*rr)->u.txt[*p] = 0;
+           break;
+       }
+           
+       default:
+           (*rr)->u.data = (unsigned char*)malloc(size);
+           memcpy((*rr)->u.data, p, size);
+       }
+       p += size;
+       rr = &(*rr)->next;
+    }
+    return r;
+}
+
+
+
+struct dns_reply *
+dns_lookup(char *domain, char *type_name)
+{
+    unsigned char reply[1024];
+    int len;
+    int type;
+    struct dns_reply *r = NULL;
+    
+    type = string_to_type(type_name);
+    len = res_search(domain, C_IN, type, reply, sizeof(reply));
+    if(len >= 0)
+       r = parse_reply(reply, len);
+    return r;
+}
+
+#else /* defined(HAVE_RES_SEARCH) && defined(HAVE_DN_EXPAND) */
+
+struct dns_reply *
+dns_lookup(char *domain, char *type_name)
+{
+    return NULL;
+}
+
+#endif
+
+#ifdef TEST
+
+int 
+main(int argc, char **argv)
+{
+    struct dns_reply *r;
+    struct resource_record *rr;
+    r = dns_lookup(argv[1], argv[2]);
+    if(r == NULL){
+       printf("No reply.\n");
+       return 1;
+    }
+    for(rr = r->head; rr;rr=rr->next){
+       printf("%s %s %d ", rr->domain, type_to_string(rr->type), rr->ttl);
+       switch(rr->type){
+       case T_NS:
+           printf("%s\n", (char*)rr->data);
+           break;
+       case T_A:
+           printf("%d.%d.%d.%d\n", 
+                  ((unsigned char*)rr->data)[0],
+                  ((unsigned char*)rr->data)[1],
+                  ((unsigned char*)rr->data)[2],
+                  ((unsigned char*)rr->data)[3]);
+           break;
+       case T_MX:
+       case T_AFSDB:{
+           struct mx_record *mx = (struct mx_record*)rr->data;
+           printf("%d %s\n", mx->preference, mx->domain);
+           break;
+       }
+       case T_SRV:{
+           struct srv_record *srv = (struct srv_record*)rr->data;
+           printf("%d %d %d %s\n", srv->priority, srv->weight, 
+                  srv->port, srv->target);
+           break;
+       }
+       default:
+           printf("\n");
+           break;
+       }
+    }
+    
+    return 0;
+}
+#endif

diff --git a/lib/roken/resolve.h b/lib/roken/resolve.h
new file mode 100644 (file)
index 0000000..2b16fa7
--- /dev/null
+++ b/lib/roken/resolve.h
@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) 1995, 1996 Kungliga Tekniska Högskolan (Royal Institute
+ * of Technology, Stockholm, Sweden).
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *      This product includes software developed by the Kungliga Tekniska
+ *      Högskolan and its contributors.
+ * 
+ * 4. Neither the name of the Institute nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/* $Id$ */
+
+/* THIS IS NOT (yet) A PUBLIC INTERFACE */
+
+
+#ifndef __RESOLVE_H__
+#define __RESOLVE_H__
+
+/* We use these, but they are not always present in <arpa/nameser.h> */
+
+#ifndef T_AFSDB
+#define T_AFSDB 18
+#endif
+#ifndef T_SRV
+#define T_SRV 33
+#endif
+
+struct dns_query{
+    char *domain;
+    int type;
+    int class;
+};
+
+struct mx_record{
+    int preference;
+    char domain[1];
+};
+
+struct srv_record{
+    int priority;
+    int weight;
+    int port;
+    char target[1];
+};
+
+struct resource_record{
+    char *domain;
+    int type;
+    int class;
+    int ttl;
+    int size;
+    union {
+       void *data;
+       struct mx_record *mx;
+       struct mx_record *afsdb; /* mx and afsdb are identical */
+       struct srv_record *srv;
+       struct in_addr *a;
+       char *txt;
+    }u;
+    struct resource_record *next;
+};
+
+
+#ifndef HAVE_ARPA_NAMESER_H /* XXX */
+typedef int HEADER; /* will never be used */
+#endif
+
+struct dns_reply{
+    HEADER h;
+    struct dns_query q;
+    struct resource_record *head;
+};
+
+
+struct dns_reply* dns_lookup(char *, char *);
+
+void dns_free_data(struct dns_reply *r);
+
+#endif /* __RESOLVE_H__ */