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-rw-r--r--resolv/ns_print.c818
1 files changed, 818 insertions, 0 deletions
diff --git a/resolv/ns_print.c b/resolv/ns_print.c
new file mode 100644
index 0000000000..cce3fb611d
--- /dev/null
+++ b/resolv/ns_print.c
@@ -0,0 +1,818 @@
+/*
+ * Copyright (c) 1996-1999 by Internet Software Consortium.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
+ * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
+ * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+ * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+ * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
+ * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+ * SOFTWARE.
+ */
+
+#ifndef lint
+static const char rcsid[] = "$Id$";
+#endif
+
+/* Import. */
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#include <netinet/in.h>
+#include <arpa/nameser.h>
+#include <arpa/inet.h>
+
+#include <errno.h>
+#include <resolv.h>
+#include <string.h>
+#include <ctype.h>
+
+#ifdef SPRINTF_CHAR
+# define SPRINTF(x) strlen(sprintf/**/x)
+#else
+# define SPRINTF(x) ((size_t)sprintf x)
+#endif
+
+/* Forward. */
+
+static size_t	prune_origin(const char *name, const char *origin);
+static int	charstr(const u_char *rdata, const u_char *edata,
+			char **buf, size_t *buflen);
+static int	addname(const u_char *msg, size_t msglen,
+			const u_char **p, const char *origin,
+			char **buf, size_t *buflen);
+static void	addlen(size_t len, char **buf, size_t *buflen);
+static int	addstr(const char *src, size_t len,
+		       char **buf, size_t *buflen);
+static int	addtab(size_t len, size_t target, int spaced,
+		       char **buf, size_t *buflen);
+
+/* Proto. */
+#ifndef _LIBC
+u_int16_t       dst_s_dns_key_id(const u_char *, const int);
+#endif
+
+/* Macros. */
+
+#define	T(x) \
+	do { \
+		if ((x) < 0) \
+			return (-1); \
+	} while (0)
+
+/* Public. */
+
+/*
+ * int
+ * ns_sprintrr(handle, rr, name_ctx, origin, buf, buflen)
+ *	Convert an RR to presentation format.
+ * return:
+ *	Number of characters written to buf, or -1 (check errno).
+ */
+int
+ns_sprintrr(const ns_msg *handle, const ns_rr *rr,
+	    const char *name_ctx, const char *origin,
+	    char *buf, size_t buflen)
+{
+	int n;
+
+	n = ns_sprintrrf(ns_msg_base(*handle), ns_msg_size(*handle),
+			 ns_rr_name(*rr), ns_rr_class(*rr), ns_rr_type(*rr),
+			 ns_rr_ttl(*rr), ns_rr_rdata(*rr), ns_rr_rdlen(*rr),
+			 name_ctx, origin, buf, buflen);
+	return (n);
+}
+
+/*
+ * int
+ * ns_sprintrrf(msg, msglen, name, class, type, ttl, rdata, rdlen,
+ *	       name_ctx, origin, buf, buflen)
+ *	Convert the fields of an RR into presentation format.
+ * return:
+ *	Number of characters written to buf, or -1 (check errno).
+ */
+int
+ns_sprintrrf(const u_char *msg, size_t msglen,
+	    const char *name, ns_class class, ns_type type,
+	    u_long ttl, const u_char *rdata, size_t rdlen,
+	    const char *name_ctx, const char *origin,
+	    char *buf, size_t buflen)
+{
+	const char *obuf = buf;
+	const u_char *edata = rdata + rdlen;
+	int spaced = 0;
+
+	const char *comment;
+	char tmp[100];
+	int len, x;
+
+	/*
+	 * Owner.
+	 */
+	if (name_ctx != NULL && ns_samename(name_ctx, name) == 1) {
+		T(addstr("\t\t\t", 3, &buf, &buflen));
+	} else {
+		len = prune_origin(name, origin);
+		if (len == 0) {
+			T(addstr("@\t\t\t", 4, &buf, &buflen));
+		} else {
+			T(addstr(name, len, &buf, &buflen));
+			/* Origin not used and no trailing dot? */
+			if ((!origin || !origin[0] || name[len] == '\0') &&
+			    name[len - 1] != '.') {
+				T(addstr(".", 1, &buf, &buflen));
+				len++;
+			}
+			T(spaced = addtab(len, 24, spaced, &buf, &buflen));
+		}
+	}
+
+	/*
+	 * TTL, Class, Type.
+	 */
+	T(x = ns_format_ttl(ttl, buf, buflen));
+	addlen(x, &buf, &buflen);
+	len = SPRINTF((tmp, " %s %s", p_class(class), p_type(type)));
+	T(addstr(tmp, len, &buf, &buflen));
+	T(spaced = addtab(x + len, 16, spaced, &buf, &buflen));
+
+	/*
+	 * RData.
+	 */
+	switch (type) {
+	case ns_t_a:
+		if (rdlen != NS_INADDRSZ)
+			goto formerr;
+		(void) inet_ntop(AF_INET, rdata, buf, buflen);
+		addlen(strlen(buf), &buf, &buflen);
+		break;
+
+	case ns_t_cname:
+	case ns_t_mb:
+	case ns_t_mg:
+	case ns_t_mr:
+	case ns_t_ns:
+	case ns_t_ptr:
+		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
+		break;
+
+	case ns_t_hinfo:
+	case ns_t_isdn:
+		/* First word. */
+		T(len = charstr(rdata, edata, &buf, &buflen));
+		if (len == 0)
+			goto formerr;
+		rdata += len;
+		T(addstr(" ", 1, &buf, &buflen));
+
+		    
+		/* Second word, optional in ISDN records. */
+		if (type == ns_t_isdn && rdata == edata)
+			break;
+		    
+		T(len = charstr(rdata, edata, &buf, &buflen));
+		if (len == 0)
+			goto formerr;
+		rdata += len;
+		break;
+
+	case ns_t_soa: {
+		u_long t;
+
+		/* Server name. */
+		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
+		T(addstr(" ", 1, &buf, &buflen));
+
+		/* Administrator name. */
+		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
+		T(addstr(" (\n", 3, &buf, &buflen));
+		spaced = 0;
+
+		if ((edata - rdata) != 5*NS_INT32SZ)
+			goto formerr;
+
+		/* Serial number. */
+		t = ns_get32(rdata);  rdata += NS_INT32SZ;
+		T(addstr("\t\t\t\t\t", 5, &buf, &buflen));
+		len = SPRINTF((tmp, "%lu", t));
+		T(addstr(tmp, len, &buf, &buflen));
+		T(spaced = addtab(len, 16, spaced, &buf, &buflen));
+		T(addstr("; serial\n", 9, &buf, &buflen));
+		spaced = 0;
+
+		/* Refresh interval. */
+		t = ns_get32(rdata);  rdata += NS_INT32SZ;
+		T(addstr("\t\t\t\t\t", 5, &buf, &buflen));
+		T(len = ns_format_ttl(t, buf, buflen));
+		addlen(len, &buf, &buflen);
+		T(spaced = addtab(len, 16, spaced, &buf, &buflen));
+		T(addstr("; refresh\n", 10, &buf, &buflen));
+		spaced = 0;
+
+		/* Retry interval. */
+		t = ns_get32(rdata);  rdata += NS_INT32SZ;
+		T(addstr("\t\t\t\t\t", 5, &buf, &buflen));
+		T(len = ns_format_ttl(t, buf, buflen));
+		addlen(len, &buf, &buflen);
+		T(spaced = addtab(len, 16, spaced, &buf, &buflen));
+		T(addstr("; retry\n", 8, &buf, &buflen));
+		spaced = 0;
+
+		/* Expiry. */
+		t = ns_get32(rdata);  rdata += NS_INT32SZ;
+		T(addstr("\t\t\t\t\t", 5, &buf, &buflen));
+		T(len = ns_format_ttl(t, buf, buflen));
+		addlen(len, &buf, &buflen);
+		T(spaced = addtab(len, 16, spaced, &buf, &buflen));
+		T(addstr("; expiry\n", 9, &buf, &buflen));
+		spaced = 0;
+
+		/* Minimum TTL. */
+		t = ns_get32(rdata);  rdata += NS_INT32SZ;
+		T(addstr("\t\t\t\t\t", 5, &buf, &buflen));
+		T(len = ns_format_ttl(t, buf, buflen));
+		addlen(len, &buf, &buflen);
+		T(addstr(" )", 2, &buf, &buflen));
+		T(spaced = addtab(len, 16, spaced, &buf, &buflen));
+		T(addstr("; minimum\n", 10, &buf, &buflen));
+
+		break;
+	    }
+
+	case ns_t_mx:
+	case ns_t_afsdb:
+	case ns_t_rt: {
+		u_int t;
+
+		if (rdlen < NS_INT16SZ)
+			goto formerr;
+
+		/* Priority. */
+		t = ns_get16(rdata);
+		rdata += NS_INT16SZ;
+		len = SPRINTF((tmp, "%u ", t));
+		T(addstr(tmp, len, &buf, &buflen));
+
+		/* Target. */
+		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
+
+		break;
+	    }
+
+	case ns_t_px: {
+		u_int t;
+
+		if (rdlen < NS_INT16SZ)
+			goto formerr;
+
+		/* Priority. */
+		t = ns_get16(rdata);
+		rdata += NS_INT16SZ;
+		len = SPRINTF((tmp, "%u ", t));
+		T(addstr(tmp, len, &buf, &buflen));
+
+		/* Name1. */
+		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
+		T(addstr(" ", 1, &buf, &buflen));
+
+		/* Name2. */
+		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
+
+		break;
+	    }
+
+	case ns_t_x25:
+		T(len = charstr(rdata, edata, &buf, &buflen));
+		if (len == 0)
+			goto formerr;
+		rdata += len;
+		break;
+
+	case ns_t_txt:
+		while (rdata < edata) {
+			T(len = charstr(rdata, edata, &buf, &buflen));
+			if (len == 0)
+				goto formerr;
+			rdata += len;
+			if (rdata < edata)
+				T(addstr(" ", 1, &buf, &buflen));
+		}
+		break;
+
+	case ns_t_nsap: {
+		char t[255*3];
+
+		(void) inet_nsap_ntoa(rdlen, rdata, t);
+		T(addstr(t, strlen(t), &buf, &buflen));
+		break;
+	    }
+
+	case ns_t_aaaa:
+		if (rdlen != NS_IN6ADDRSZ)
+			goto formerr;
+		(void) inet_ntop(AF_INET6, rdata, buf, buflen);
+		addlen(strlen(buf), &buf, &buflen);
+		break;
+
+	case ns_t_loc: {
+		char t[255];
+
+		/* XXX protocol format checking? */
+		(void) loc_ntoa(rdata, t);
+		T(addstr(t, strlen(t), &buf, &buflen));
+		break;
+	    }
+
+	case ns_t_naptr: {
+		u_int order, preference;
+		char t[50];
+
+		if (rdlen < 2*NS_INT16SZ)
+			goto formerr;
+
+		/* Order, Precedence. */
+		order = ns_get16(rdata);	rdata += NS_INT16SZ;
+		preference = ns_get16(rdata);	rdata += NS_INT16SZ;
+		len = SPRINTF((t, "%u %u ", order, preference));
+		T(addstr(t, len, &buf, &buflen));
+
+		/* Flags. */
+		T(len = charstr(rdata, edata, &buf, &buflen));
+		if (len == 0)
+			goto formerr;
+		rdata += len;
+		T(addstr(" ", 1, &buf, &buflen));
+
+		/* Service. */
+		T(len = charstr(rdata, edata, &buf, &buflen));
+		if (len == 0)
+			goto formerr;
+		rdata += len;
+		T(addstr(" ", 1, &buf, &buflen));
+
+		/* Regexp. */
+		T(len = charstr(rdata, edata, &buf, &buflen));
+		if (len < 0)
+			return (-1);
+		if (len == 0)
+			goto formerr;
+		rdata += len;
+		T(addstr(" ", 1, &buf, &buflen));
+
+		/* Server. */
+		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
+		break;
+	    }
+
+	case ns_t_srv: {
+		u_int priority, weight, port;
+		char t[50];
+
+		if (rdlen < NS_INT16SZ*3)
+			goto formerr;
+
+		/* Priority, Weight, Port. */
+		priority = ns_get16(rdata);  rdata += NS_INT16SZ;
+		weight   = ns_get16(rdata);  rdata += NS_INT16SZ;
+		port     = ns_get16(rdata);  rdata += NS_INT16SZ;
+		len = SPRINTF((t, "%u %u %u ", priority, weight, port));
+		T(addstr(t, len, &buf, &buflen));
+
+		/* Server. */
+		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
+		break;
+	    }
+
+	case ns_t_minfo:
+	case ns_t_rp:
+		/* Name1. */
+		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
+		T(addstr(" ", 1, &buf, &buflen));
+
+		/* Name2. */
+		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
+
+		break;
+
+	case ns_t_wks: {
+		int n, lcnt;
+
+		if (rdlen < NS_INT32SZ + 1)
+			goto formerr;
+
+		/* Address. */
+		(void) inet_ntop(AF_INET, rdata, buf, buflen);
+		addlen(strlen(buf), &buf, &buflen);
+		rdata += NS_INADDRSZ;
+
+		/* Protocol. */
+		len = SPRINTF((tmp, " %u ( ", *rdata));
+		T(addstr(tmp, len, &buf, &buflen));
+		rdata += NS_INT8SZ;
+
+		/* Bit map. */
+		n = 0;
+		lcnt = 0;
+		while (rdata < edata) {
+			u_int c = *rdata++;
+			do {
+				if (c & 0200) {
+					if (lcnt == 0) {
+						T(addstr("\n\t\t\t\t", 5,
+							 &buf, &buflen));
+						lcnt = 10;
+						spaced = 0;
+					}
+					len = SPRINTF((tmp, "%d ", n));
+					T(addstr(tmp, len, &buf, &buflen));
+					lcnt--;
+				}
+				c <<= 1;
+			} while (++n & 07);
+		}
+		T(addstr(")", 1, &buf, &buflen));
+
+		break;
+	    }
+
+	case ns_t_key: {
+#ifndef _LIBC
+		char base64_key[NS_MD5RSA_MAX_BASE64];
+		u_int keyflags, protocol, algorithm, key_id;
+		const char *leader;
+		int n;
+
+		if (rdlen < NS_INT16SZ + NS_INT8SZ + NS_INT8SZ)
+			goto formerr;
+
+		/* Key flags, Protocol, Algorithm. */
+		key_id = dst_s_dns_key_id(rdata, edata-rdata);
+		keyflags = ns_get16(rdata);  rdata += NS_INT16SZ;
+		protocol = *rdata++;
+		algorithm = *rdata++;
+		len = SPRINTF((tmp, "0x%04x %u %u",
+			       keyflags, protocol, algorithm));
+		T(addstr(tmp, len, &buf, &buflen));
+
+		/* Public key data. */
+		len = b64_ntop(rdata, edata - rdata,
+			       base64_key, sizeof base64_key);
+		if (len < 0)
+			goto formerr;
+		if (len > 15) {
+			T(addstr(" (", 2, &buf, &buflen));
+			leader = "\n\t\t";
+			spaced = 0;
+		} else
+			leader = " ";
+		for (n = 0; n < len; n += 48) {
+			T(addstr(leader, strlen(leader), &buf, &buflen));
+			T(addstr(base64_key + n, MIN(len - n, 48),
+				 &buf, &buflen));
+		}
+		if (len > 15)
+			T(addstr(" )", 2, &buf, &buflen));
+		n = SPRINTF((tmp, " ; key_tag= %u", key_id));
+		T(addstr(tmp, n, &buf, &buflen));
+#endif /* !_LIBC */
+		break;
+	    }
+
+	case ns_t_sig: {
+#ifndef _LIBC
+		char base64_key[NS_MD5RSA_MAX_BASE64];
+		u_int type, algorithm, labels, footprint;
+		const char *leader;
+		u_long t;
+		int n;
+
+		if (rdlen < 22)
+			goto formerr;
+
+		/* Type covered, Algorithm, Label count, Original TTL. */
+	        type = ns_get16(rdata);  rdata += NS_INT16SZ;
+		algorithm = *rdata++;
+		labels = *rdata++;
+		t = ns_get32(rdata);  rdata += NS_INT32SZ;
+		len = SPRINTF((tmp, "%s %d %d %lu ",
+			       p_type(type), algorithm, labels, t));
+		T(addstr(tmp, len, &buf, &buflen));
+		if (labels > (u_int)dn_count_labels(name))
+			goto formerr;
+
+		/* Signature expiry. */
+		t = ns_get32(rdata);  rdata += NS_INT32SZ;
+		len = SPRINTF((tmp, "%s ", p_secstodate(t)));
+		T(addstr(tmp, len, &buf, &buflen));
+
+		/* Time signed. */
+		t = ns_get32(rdata);  rdata += NS_INT32SZ;
+		len = SPRINTF((tmp, "%s ", p_secstodate(t)));
+		T(addstr(tmp, len, &buf, &buflen));
+
+		/* Signature Footprint. */
+		footprint = ns_get16(rdata);  rdata += NS_INT16SZ;
+		len = SPRINTF((tmp, "%u ", footprint));
+		T(addstr(tmp, len, &buf, &buflen));
+
+		/* Signer's name. */
+		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
+
+		/* Signature. */
+		len = b64_ntop(rdata, edata - rdata,
+			       base64_key, sizeof base64_key);
+		if (len > 15) {
+			T(addstr(" (", 2, &buf, &buflen));
+			leader = "\n\t\t";
+			spaced = 0;
+		} else
+			leader = " ";
+		if (len < 0)
+			goto formerr;
+		for (n = 0; n < len; n += 48) {
+			T(addstr(leader, strlen(leader), &buf, &buflen));
+			T(addstr(base64_key + n, MIN(len - n, 48),
+				 &buf, &buflen));
+		}
+		if (len > 15)
+			T(addstr(" )", 2, &buf, &buflen));
+#endif /* !_LIBC */
+		break;
+	    }
+
+	case ns_t_nxt: {
+		int n, c;
+
+		/* Next domain name. */
+		T(addname(msg, msglen, &rdata, origin, &buf, &buflen));
+
+		/* Type bit map. */
+		n = edata - rdata;
+		for (c = 0; c < n*8; c++)
+			if (NS_NXT_BIT_ISSET(c, rdata)) {
+				len = SPRINTF((tmp, " %s", p_type(c)));
+				T(addstr(tmp, len, &buf, &buflen));
+			}
+		break;
+	    }
+
+	case ns_t_cert: {
+		u_int c_type, key_tag, alg;
+		int n, siz;
+		char base64_cert[8192], *leader, tmp[40];
+
+		c_type  = ns_get16(rdata); rdata += NS_INT16SZ;
+		key_tag = ns_get16(rdata); rdata += NS_INT16SZ;
+		alg = (u_int) *rdata++;
+
+		len = SPRINTF((tmp, "%d %d %d ", c_type, key_tag, alg));
+		T(addstr(tmp, len, &buf, &buflen));
+		siz = (edata-rdata)*4/3 + 4; /* "+4" accounts for trailing \0 */
+		if (siz > sizeof(base64_cert) * 3/4) {
+			char *str = "record too long to print";
+			T(addstr(str, strlen(str), &buf, &buflen));
+		}
+		else {
+			len = b64_ntop(rdata, edata-rdata, base64_cert, siz);
+
+			if (len < 0)
+				goto formerr;
+			else if (len > 15) {
+				T(addstr(" (", 2, &buf, &buflen));
+				leader = "\n\t\t";
+				spaced = 0;
+			}
+			else
+				leader = " ";
+	
+			for (n = 0; n < len; n += 48) {
+				T(addstr(leader, strlen(leader),
+					 &buf, &buflen));
+				T(addstr(base64_cert + n, MIN(len - n, 48),
+					 &buf, &buflen));
+			}
+			if (len > 15)
+				T(addstr(" )", 2, &buf, &buflen));
+		}
+		break;
+	    }
+
+	case ns_t_tsig: {
+		/* BEW - need to complete this */
+		int n;
+
+		T(len = addname(msg, msglen, &rdata, origin, &buf, &buflen));
+		T(addstr(" ", 1, &buf, &buflen));
+		rdata += 8; /* time */
+		n = ns_get16(rdata); rdata += INT16SZ;
+		rdata += n; /* sig */
+		n = ns_get16(rdata); rdata += INT16SZ; /* original id */
+		sprintf(buf, "%d", ns_get16(rdata));
+		rdata += INT16SZ;
+		addlen(strlen(buf), &buf, &buflen);
+		break;
+	    }
+
+	default:
+		comment = "unknown RR type";
+		goto hexify;
+	}
+	return (buf - obuf);
+ formerr:
+	comment = "RR format error";
+ hexify: {
+	int n, m;
+	char *p;
+
+	len = SPRINTF((tmp, "\\#(\t\t; %s", comment));
+	T(addstr(tmp, len, &buf, &buflen));
+	while (rdata < edata) {
+		p = tmp;
+		p += SPRINTF((p, "\n\t"));
+		spaced = 0;
+		n = MIN(16, edata - rdata);
+		for (m = 0; m < n; m++)
+			p += SPRINTF((p, "%02x ", rdata[m]));
+		T(addstr(tmp, p - tmp, &buf, &buflen));
+		if (n < 16) {
+			T(addstr(")", 1, &buf, &buflen));
+			T(addtab(p - tmp + 1, 48, spaced, &buf, &buflen));
+		}
+		p = tmp;
+		p += SPRINTF((p, "; "));
+		for (m = 0; m < n; m++)
+			*p++ = (isascii(rdata[m]) && isprint(rdata[m]))
+				? rdata[m]
+				: '.';
+		T(addstr(tmp, p - tmp, &buf, &buflen));
+		rdata += n;
+	}
+	return (buf - obuf);
+    }
+}
+
+/* Private. */
+
+/*
+ * size_t
+ * prune_origin(name, origin)
+ *	Find out if the name is at or under the current origin.
+ * return:
+ *	Number of characters in name before start of origin,
+ *	or length of name if origin does not match.
+ * notes:
+ *	This function should share code with samedomain().
+ */
+static size_t
+prune_origin(const char *name, const char *origin) {
+	const char *oname = name;
+
+	while (*name != '\0') {
+		if (origin != NULL && ns_samename(name, origin) == 1)
+			return (name - oname - (name > oname));
+		while (*name != '\0') {
+			if (*name == '\\') {
+				name++;
+				/* XXX need to handle \nnn form. */
+				if (*name == '\0')
+					break;
+			} else if (*name == '.') {
+				name++;
+				break;
+			}
+			name++;
+		}
+	}
+	return (name - oname);
+}
+
+/*
+ * int
+ * charstr(rdata, edata, buf, buflen)
+ *	Format a <character-string> into the presentation buffer.
+ * return:
+ *	Number of rdata octets consumed
+ *	0 for protocol format error
+ *	-1 for output buffer error
+ * side effects:
+ *	buffer is advanced on success.
+ */
+static int
+charstr(const u_char *rdata, const u_char *edata, char **buf, size_t *buflen) {
+	const u_char *odata = rdata;
+	size_t save_buflen = *buflen;
+	char *save_buf = *buf;
+
+	if (addstr("\"", 1, buf, buflen) < 0)
+		goto enospc;
+	if (rdata < edata) {
+		int n = *rdata;
+
+		if (rdata + 1 + n <= edata) {
+			rdata++;
+			while (n-- > 0) {
+				if (strchr("\n\"\\", *rdata) != NULL)
+					if (addstr("\\", 1, buf, buflen) < 0)
+						goto enospc;
+				if (addstr((const char *)rdata, 1,
+					   buf, buflen) < 0)
+					goto enospc;
+				rdata++;
+			}
+		}
+	}
+	if (addstr("\"", 1, buf, buflen) < 0)
+		goto enospc;
+	return (rdata - odata);
+ enospc:
+	__set_errno (ENOSPC);
+	*buf = save_buf;
+	*buflen = save_buflen;
+	return (-1);
+}
+
+static int
+addname(const u_char *msg, size_t msglen,
+	const u_char **pp, const char *origin,
+	char **buf, size_t *buflen)
+{
+	size_t newlen, save_buflen = *buflen;
+	char *save_buf = *buf;
+	int n;
+
+	n = dn_expand(msg, msg + msglen, *pp, *buf, *buflen);
+	if (n < 0)
+		goto enospc;	/* Guess. */
+	newlen = prune_origin(*buf, origin);
+	if ((origin == NULL || origin[0] == '\0' || (*buf)[newlen] == '\0') &&
+	    (newlen == 0 || (*buf)[newlen - 1] != '.')) {
+		/* No trailing dot. */
+		if (newlen + 2 > *buflen)
+			goto enospc;	/* No room for ".\0". */
+		(*buf)[newlen++] = '.';
+		(*buf)[newlen] = '\0';
+	}
+	if (newlen == 0) {
+		/* Use "@" instead of name. */
+		if (newlen + 2 > *buflen)
+			goto enospc;        /* No room for "@\0". */
+		(*buf)[newlen++] = '@';
+		(*buf)[newlen] = '\0';
+	}
+	*pp += n;
+	addlen(newlen, buf, buflen);
+	**buf = '\0';
+	return (newlen);
+ enospc:
+	__set_errno (ENOSPC);
+	*buf = save_buf;
+	*buflen = save_buflen;
+	return (-1);
+}
+
+static void
+addlen(size_t len, char **buf, size_t *buflen) {
+#if 0
+	INSIST(len <= *buflen);
+#endif
+	*buf += len;
+	*buflen -= len;
+}
+
+static int
+addstr(const char *src, size_t len, char **buf, size_t *buflen) {
+	if (len >= *buflen) {
+		__set_errno (ENOSPC);
+		return (-1);
+	}
+	memcpy(*buf, src, len);
+	addlen(len, buf, buflen);
+	**buf = '\0';
+	return (0);
+}
+
+static int
+addtab(size_t len, size_t target, int spaced, char **buf, size_t *buflen) {
+	size_t save_buflen = *buflen;
+	char *save_buf = *buf;
+	int t;
+
+	if (spaced || len >= target - 1) {
+		T(addstr("  ", 2, buf, buflen));
+		spaced = 1;
+	} else {
+		for (t = (target - len - 1) / 8; t >= 0; t--)
+			if (addstr("\t", 1, buf, buflen) < 0) {
+				*buflen = save_buflen;
+				*buf = save_buf;
+				return (-1);
+			}
+		spaced = 0;
+	}
+	return (spaced);
+}