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Diffstat (limited to 'src/lib/krb5/os/hst_realm.c')
-rw-r--r--src/lib/krb5/os/hst_realm.c182
1 files changed, 38 insertions, 144 deletions
diff --git a/src/lib/krb5/os/hst_realm.c b/src/lib/krb5/os/hst_realm.c
index be538a0..574fe70 100644
--- a/src/lib/krb5/os/hst_realm.c
+++ b/src/lib/krb5/os/hst_realm.c
@@ -65,6 +65,8 @@
* host names should be in the usual form (e.g. FOO.BAR.BAZ)
*/
+#include "dnsglue.h"
+
#define NEED_SOCKETS
#include "k5-int.h"
#include "os-proto.h"
@@ -76,30 +78,8 @@
#include <strings.h>
#endif
-#ifdef KRB5_DNS_LOOKUP
-#ifdef WSHELPER
-#include <wshelper.h>
-#else /* WSHELPER */
-#include <netinet/in.h>
-#include <arpa/inet.h>
-#include <arpa/nameser.h>
-#ifndef T_TXT /* not defined on SunOS 4 */
-# define T_TXT 15
-#endif
-#include <resolv.h>
-#include <netdb.h>
-#endif /* WSHELPER */
-#endif /* KRB5_DNS_LOOKUP */
-
#include "fake-addrinfo.h"
-/* for old Unixes and friends ... */
-#ifndef MAXHOSTNAMELEN
-#define MAXHOSTNAMELEN 64
-#endif
-
-#define MAX_DNS_NAMELEN (15*(MAXHOSTNAMELEN + 1)+1)
-
#ifdef KRB5_DNS_LOOKUP
/*
* Try to look up a TXT record pointing to a Kerberos realm
@@ -108,14 +88,11 @@
krb5_error_code
krb5_try_realm_txt_rr(const char *prefix, const char *name, char **realm)
{
- union {
- unsigned char bytes[2048];
- HEADER hdr;
- } answer;
- unsigned char *p;
- char host[MAX_DNS_NAMELEN], *h;
- int size;
- int type, rrclass, numanswers, numqueries, rdlen, len;
+ krb5_error_code retval = KRB5_ERR_HOST_REALM_UNKNOWN;
+ const unsigned char *p, *base;
+ char host[MAXDNAME], *h;
+ int ret, rdlen, len;
+ struct krb5int_dns_state *ds = NULL;
/*
* Form our query, and send it via DNS
@@ -126,7 +103,7 @@ krb5_try_realm_txt_rr(const char *prefix, const char *name, char **realm)
return KRB5_ERR_HOST_REALM_UNKNOWN;
strcpy(host,prefix);
} else {
- if ( strlen(prefix) + strlen(name) + 3 > MAX_DNS_NAMELEN )
+ if ( strlen(prefix) + strlen(name) + 3 > MAXDNAME )
return KRB5_ERR_HOST_REALM_UNKNOWN;
sprintf(host,"%s.%s", prefix, name);
@@ -144,119 +121,36 @@ krb5_try_realm_txt_rr(const char *prefix, const char *name, char **realm)
if ((h > host) && (h[-1] != '.') && ((h - host + 1) < sizeof(host)))
strcpy (h, ".");
}
-#ifdef HAVE_RES_NSEARCH
- {
- res_state statp;
- /* Weird... the man pages I've been looking at (Solaris 9) say
- we pass a res_state object (which is a pointer) into
- various routines, but they don't say much of anything about
- what it should point to initially or how it should be
- allocated.
-
- They also give no indication what the return value of
- res_ninit is. */
- typedef union {
- struct sockaddr_storage ss;
- INT64_TYPE i64;
- double d;
- } aligned_thing;
- aligned_thing statp_buf[(sizeof(*statp) + sizeof(aligned_thing) - 1) / sizeof(aligned_thing)];
- int n;
-
- statp = (res_state) &statp_buf;
- memset(&statp_buf, 0, sizeof(statp_buf));
- n = res_ninit(statp);
- /* ignore n? */
- size = res_nsearch(statp, host, C_IN, T_TXT,
- answer.bytes, sizeof(answer.bytes));
+ ret = krb5int_dns_init(&ds, host, C_IN, T_TXT);
+ if (ret < 0)
+ goto errout;
+
+ ret = krb5int_dns_nextans(ds, &base, &rdlen);
+ if (ret < 0 || base == NULL)
+ goto errout;
+
+ p = base;
+ if (!INCR_OK(base, rdlen, p, 1))
+ goto errout;
+ len = *p++;
+ *realm = malloc((size_t)len + 1);
+ if (*realm == NULL) {
+ retval = ENOMEM;
+ goto errout;
}
-#else
- size = res_search(host, C_IN, T_TXT, answer.bytes, sizeof(answer.bytes));
-#endif
-
- if ((size < sizeof(HEADER)) || (size > sizeof(answer.bytes)))
- return KRB5_ERR_HOST_REALM_UNKNOWN;
-
- p = answer.bytes;
-
- numqueries = ntohs(answer.hdr.qdcount);
- numanswers = ntohs(answer.hdr.ancount);
-
- p += sizeof(HEADER);
-
- /*
- * We need to skip over the questions before we can get to the answers,
- * which means we have to iterate over every query record. We use
- * dn_expand to tell us how long each compressed name is.
- */
-
-#define INCR_CHECK(x, y) x += y; if (x > size + answer.bytes) \
- return KRB5_ERR_HOST_REALM_UNKNOWN
-#define CHECK(x, y) if (x + y > size + answer.bytes) \
- return KRB5_ERR_HOST_REALM_UNKNOWN
-#define NTOHSP(x, y) x[0] << 8 | x[1]; x += y
-
- while (numqueries--) {
- len = dn_expand(answer.bytes, answer.bytes + size, p, host,
- sizeof(host));
- if (len < 0)
- return KRB5_ERR_HOST_REALM_UNKNOWN;
- INCR_CHECK(p, len + 4); /* Name plus type plus class */
- }
-
- /*
- * We're now pointing at the answer records. Process the first
- * TXT record we find.
- */
-
- while (numanswers--) {
-
- /* First the name; use dn_expand to get the compressed size */
- len = dn_expand(answer.bytes, answer.bytes + size, p,
- host, sizeof(host));
- if (len < 0)
- return KRB5_ERR_HOST_REALM_UNKNOWN;
- INCR_CHECK(p, len);
-
- /* Next is the query type */
- CHECK(p, 2);
- type = NTOHSP(p,2);
-
- /* Next is the query class; also skip over 4 byte TTL */
- CHECK(p,6);
- rrclass = NTOHSP(p,6);
-
- /* Record data length - make sure we aren't truncated */
-
- CHECK(p,2);
- rdlen = NTOHSP(p,2);
-
- if (p + rdlen > answer.bytes + size)
- return KRB5_ERR_HOST_REALM_UNKNOWN;
-
- /*
- * If this is a TXT record, return the string. Note that the
- * string has a 1-byte length in the front
- */
- /* XXX What about flagging multiple TXT records as an error? */
-
- if (rrclass == C_IN && type == T_TXT) {
- len = *p++;
- if (p + len > answer.bytes + size)
- return KRB5_ERR_HOST_REALM_UNKNOWN;
- *realm = malloc(len + 1);
- if (*realm == NULL)
- return ENOMEM;
- strncpy(*realm, (char *) p, len);
- (*realm)[len] = '\0';
- /* Avoid a common error. */
- if ( (*realm)[len-1] == '.' )
- (*realm)[len-1] = '\0';
- return 0;
- }
+ strncpy(*realm, (const char *)p, (size_t)len);
+ (*realm)[len] = '\0';
+ /* Avoid a common error. */
+ if ( (*realm)[len-1] == '.' )
+ (*realm)[len-1] = '\0';
+ retval = 0;
+
+errout:
+ if (ds != NULL) {
+ krb5int_dns_fini(ds);
+ ds = NULL;
}
-
- return KRB5_ERR_HOST_REALM_UNKNOWN;
+ return retval;
}
#endif /* KRB5_DNS_LOOKUP */
@@ -301,7 +195,7 @@ krb5_get_host_realm(krb5_context context, const char *host, char ***realmsp)
char *default_realm, *realm, *cp, *temp_realm;
krb5_error_code retval;
int l;
- char local_host[MAX_DNS_NAMELEN+1];
+ char local_host[MAXDNAME+1];
if (host) {
/* Filter out numeric addresses if the caller utterly failed to
@@ -326,7 +220,7 @@ krb5_get_host_realm(krb5_context context, const char *host, char ***realmsp)
/* IPv6 numeric address form? Bye bye. */
return KRB5_ERR_NUMERIC_REALM;
- /* Should probably error out if strlen(host) > MAX_DNS_NAMELEN. */
+ /* Should probably error out if strlen(host) > MAXDNAME. */
strncpy(local_host, host, sizeof(local_host));
local_host[sizeof(local_host) - 1] = '\0';
} else {
generated by cgit v1.1 at 2024-07-10 03:18:34 +0000