1 files changed, 163 insertions, 0 deletions
diff --git a/src/dns/dns_rr_to_sa.c b/src/dns/dns_rr_to_sa.c
new file mode 100644
index 0000000..f264260
--- /dev/null
+++ b/src/dns/dns_rr_to_sa.c
@@ -0,0 +1,163 @@
+/*++
+/* NAME
+/*	dns_rr_to_sa 3
+/* SUMMARY
+/*	resource record to socket address
+/* SYNOPSIS
+/*	#include <dns.h>
+/*
+/*	int	dns_rr_to_sa(rr, port, sa, sa_length)
+/*	DNS_RR	*rr;
+/*	unsigned port;
+/*	struct sockaddr *sa;
+/*	SOCKADDR_SIZE *sa_length;
+/* DESCRIPTION
+/*	dns_rr_to_sa() converts the address in a DNS resource record into
+/*	a socket address of the corresponding type.
+/*
+/*	Arguments:
+/* .IP rr
+/*	DNS resource record pointer.
+/* .IP port
+/*	TCP or UDP port, network byte order.
+/* .IP sa
+/*	Socket address pointer.
+/* .IP sa_length
+/*	On input, the available socket address storage space.
+/*	On output, the amount of space actually used.
+/* DIAGNOSTICS
+/*	The result is non-zero in case of problems, with the
+/*	error type returned via the errno variable.
+/* LICENSE
+/* .ad
+/* .fi
+/*	The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/*	Wietse Venema
+/*	IBM T.J. Watson Research
+/*	P.O. Box 704
+/*	Yorktown Heights, NY 10598, USA
+/*--*/
+
+/* System libraries. */
+
+#include <sys_defs.h>
+#include <errno.h>
+
+/* Utility library. */
+
+#include <msg.h>
+
+/* DNS library. */
+
+#include <dns.h>
+
+/* dns_rr_to_sa - resource record to socket address */
+
+int     dns_rr_to_sa(DNS_RR *rr, unsigned port, struct sockaddr *sa,
+		             SOCKADDR_SIZE *sa_length)
+{
+    SOCKADDR_SIZE sock_addr_len;
+
+    if (rr->type == T_A) {
+	if (rr->data_len != sizeof(SOCK_ADDR_IN_ADDR(sa))) {
+	    errno = EINVAL;
+	    return (-1);
+	} else if ((sock_addr_len = sizeof(*SOCK_ADDR_IN_PTR(sa))) > *sa_length) {
+	    errno = ENOSPC;
+	    return (-1);
+	} else {
+	    memset((void *) SOCK_ADDR_IN_PTR(sa), 0, sock_addr_len);
+	    SOCK_ADDR_IN_FAMILY(sa) = AF_INET;
+	    SOCK_ADDR_IN_PORT(sa) = port;
+	    SOCK_ADDR_IN_ADDR(sa) = IN_ADDR(rr->data);
+#ifdef HAS_SA_LEN
+	    sa->sa_len = sock_addr_len;
+#endif
+	    *sa_length = sock_addr_len;
+	    return (0);
+	}
+#ifdef HAS_IPV6
+    } else if (rr->type == T_AAAA) {
+	if (rr->data_len != sizeof(SOCK_ADDR_IN6_ADDR(sa))) {
+	    errno = EINVAL;
+	    return (-1);
+	} else if ((sock_addr_len = sizeof(*SOCK_ADDR_IN6_PTR(sa))) > *sa_length) {
+	    errno = ENOSPC;
+	    return (-1);
+	} else {
+	    memset((void *) SOCK_ADDR_IN6_PTR(sa), 0, sock_addr_len);
+	    SOCK_ADDR_IN6_FAMILY(sa) = AF_INET6;
+	    SOCK_ADDR_IN6_PORT(sa) = port;
+	    SOCK_ADDR_IN6_ADDR(sa) = IN6_ADDR(rr->data);
+#ifdef HAS_SA_LEN
+	    sa->sa_len = sock_addr_len;
+#endif
+	    *sa_length = sock_addr_len;
+	    return (0);
+	}
+#endif
+    } else {
+	errno = EAFNOSUPPORT;
+	return (-1);
+    }
+}
+
+ /*
+  * Stand-alone test program.
+  */
+#ifdef TEST
+#include <stdlib.h>
+
+#include <stringops.h>
+#include <vstream.h>
+#include <myaddrinfo.h>
+
+static const char *myname;
+
+static NORETURN usage(void)
+{
+    msg_fatal("usage: %s dnsaddrtype hostname portnumber", myname);
+}
+
+int     main(int argc, char **argv)
+{
+    DNS_RR *rr;
+    MAI_HOSTADDR_STR hostaddr;
+    MAI_SERVPORT_STR portnum;
+    struct sockaddr_storage ss;
+    struct sockaddr *sa = (struct sockaddr *) &ss;
+    SOCKADDR_SIZE sa_length = sizeof(ss);
+    VSTRING *why;
+    int     type;
+    int     port;
+
+    myname = argv[0];
+    if (argc < 4)
+	usage();
+    why = vstring_alloc(1);
+
+    while (*++argv) {
+	if (argv[1] == 0 || argv[2] == 0)
+	    usage();
+	if ((type = dns_type(argv[0])) == 0)
+	    usage();
+	if (!alldig(argv[2]) || (port = atoi(argv[2])) > 65535)
+	    usage();
+	if (dns_lookup(argv[1], type, 0, &rr, (VSTRING *) 0, why) != DNS_OK)
+	    msg_fatal("%s: %s", argv[1], vstring_str(why));
+	sa_length = sizeof(ss);
+	if (dns_rr_to_sa(rr, htons(port), sa, &sa_length) != 0)
+	    msg_fatal("dns_rr_to_sa: %m");
+	SOCKADDR_TO_HOSTADDR(sa, sa_length, &hostaddr, &portnum, 0);
+	vstream_printf("%s %s -> %s %s\n",
+		       argv[1], argv[2], hostaddr.buf, portnum.buf);
+	vstream_fflush(VSTREAM_OUT);
+	argv += 2;
+	dns_rr_free(rr);
+    }
+    vstring_free(why);
+    return (0);
+}
+
+#endif