1 files changed, 117 insertions, 0 deletions
diff --git a/src/dns/dns_strrecord.c b/src/dns/dns_strrecord.c
new file mode 100644
index 0000000..6b8e989
--- /dev/null
+++ b/src/dns/dns_strrecord.c
@@ -0,0 +1,117 @@
+/*++
+/* NAME
+/*	dns_strrecord 3
+/* SUMMARY
+/*	name service resource record printable forms
+/* SYNOPSIS
+/*	#include <dns.h>
+/*
+/*	char	*dns_strrecord(buf, record)
+/*	VSTRING	*buf;
+/*	DNS_RR	*record;
+/* DESCRIPTION
+/*	dns_strrecord() formats a DNS resource record as "name ttl
+/*	class type preference value", where the class field is
+/*	always "IN", the preference field exists only for MX records,
+/*	and all names end in ".". The result value is the payload
+/*	of the buffer argument.
+/* 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
+/*
+/*	Wietse Venema
+/*	Google, Inc.
+/*	111 8th Avenue
+/*	New York, NY 10011, USA
+/*--*/
+
+/* System library. */
+
+#include <sys_defs.h>
+#include <string.h>			/* memcpy */
+
+/* Utility library. */
+
+#include <vstring.h>
+#include <msg.h>
+
+/* DNS library. */
+
+#include <dns.h>
+
+/* dns_strrecord - format resource record as generic string */
+
+char   *dns_strrecord(VSTRING *buf, DNS_RR *rr)
+{
+    const char myname[] = "dns_strrecord";
+    MAI_HOSTADDR_STR host;
+    UINT32_TYPE soa_buf[5];
+
+    vstring_sprintf(buf, "%s. %u IN %s ",
+		    rr->rname, rr->ttl, dns_strtype(rr->type));
+    switch (rr->type) {
+    case T_A:
+#ifdef T_AAAA
+    case T_AAAA:
+#endif
+	if (dns_rr_to_pa(rr, &host) == 0)
+	    msg_fatal("%s: conversion error for resource record type %s: %m",
+		      myname, dns_strtype(rr->type));
+	vstring_sprintf_append(buf, "%s", host.buf);
+	break;
+    case T_CNAME:
+    case T_DNAME:
+    case T_MB:
+    case T_MG:
+    case T_MR:
+    case T_NS:
+    case T_PTR:
+	vstring_sprintf_append(buf, "%s.", rr->data);
+	break;
+    case T_TXT:
+	vstring_sprintf_append(buf, "%s", rr->data);
+	break;
+    case T_MX:
+	vstring_sprintf_append(buf, "%u %s.", rr->pref, rr->data);
+	break;
+    case T_TLSA:
+	if (rr->data_len >= 3) {
+	    uint8_t *ip = (uint8_t *) rr->data;
+	    uint8_t usage = *ip++;
+	    uint8_t selector = *ip++;
+	    uint8_t mtype = *ip++;
+	    unsigned i;
+
+	    /* /\.example\. \d+ IN TLSA \d+ \d+ \d+ [\da-f]*$/ IGNORE */
+	    vstring_sprintf_append(buf, "%d %d %d ", usage, selector, mtype);
+	    for (i = 3; i < rr->data_len; ++i)
+		vstring_sprintf_append(buf, "%02x", *ip++);
+	} else {
+	    vstring_sprintf_append(buf, "[truncated record]");
+	}
+
+	/*
+	 * We use the SOA record TTL to determine the negative reply TTL. We
+	 * save the time fields in the SOA record for debugging, but for now
+	 * we don't bother saving the source host and mailbox information, as
+	 * that would require changes to the DNS_RR structure. See also code
+	 * in dns_get_rr().
+	 */
+    case T_SOA:
+	memcpy(soa_buf, rr->data, sizeof(soa_buf));
+	vstring_sprintf_append(buf, "- - %u %u %u %u %u",
+			       soa_buf[0], soa_buf[1], soa_buf[2],
+			       soa_buf[3], soa_buf[4]);
+	break;
+    default:
+	msg_fatal("%s: don't know how to print type %s",
+		  myname, dns_strtype(rr->type));
+    }
+    return (vstring_str(buf));
+}