Imported from /home/lorry/working-area/delta_isc-dhcp-tarball/dhcp-4.2.8.tar.gz.HEADdhcp-4.2.8master

1 files changed, 789 insertions, 0 deletions

diff --git a/common/ns_name.c b/common/ns_name.c
new file mode 100644
index 0000000..829fe14
--- /dev/null
+++ b/common/ns_name.c
@@ -0,0 +1,789 @@
+/*
+ * Copyright (c) 2004,2009,2014 by Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (c) 1996-2003 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 ISC DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC 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.
+ *
+ *   Internet Systems Consortium, Inc.
+ *   950 Charter Street
+ *   Redwood City, CA 94063
+ *   <info@isc.org>
+ *   http://www.isc.org/
+ */
+
+#include <sys/types.h>
+
+#include <netinet/in.h>
+#include <sys/socket.h>
+
+#include <errno.h>
+#include <string.h>
+#include <ctype.h>
+
+#include "minires.h"
+#include "arpa/nameser.h"
+
+/* Data. */
+
+static const char	digits[] = "0123456789";
+
+/* Forward. */
+
+static int		special(int);
+static int		printable(int);
+static int		dn_find(const u_char *, const u_char *,
+				const u_char * const *,
+				const u_char * const *);
+
+/* Public. */
+
+/*
+ * MRns_name_ntop(src, dst, dstsiz)
+ *	Convert an encoded domain name to printable ascii as per RFC1035.
+ * return:
+ *	Number of bytes written to buffer, or -1 (with errno set)
+ * notes:
+ *	The root is returned as "."
+ *	All other domains are returned in non absolute form
+ */
+int
+MRns_name_ntop(const u_char *src, char *dst, size_t dstsiz) {
+	const u_char *cp;
+	char *dn, *eom;
+	u_char c;
+	u_int n;
+
+	cp = src;
+	dn = dst;
+	eom = dst + dstsiz;
+
+	while ((n = *cp++) != 0) {
+		if ((n & NS_CMPRSFLGS) != 0) {
+			/* Some kind of compression pointer. */
+			errno = EMSGSIZE;
+			return (-1);
+		}
+		if (dn != dst) {
+			if (dn >= eom) {
+				errno = EMSGSIZE;
+				return (-1);
+			}
+			*dn++ = '.';
+		}
+		if (dn + n >= eom) {
+			errno = EMSGSIZE;
+			return (-1);
+		}
+		for ((void)NULL; n > 0; n--) {
+			c = *cp++;
+			if (special(c)) {
+				if (dn + 1 >= eom) {
+					errno = EMSGSIZE;
+					return (-1);
+				}
+				*dn++ = '\\';
+				*dn++ = (char)c;
+			} else if (!printable(c)) {
+				if (dn + 3 >= eom) {
+					errno = EMSGSIZE;
+					return (-1);
+				}
+				*dn++ = '\\';
+				*dn++ = digits[c / 100];
+				*dn++ = digits[(c % 100) / 10];
+				*dn++ = digits[c % 10];
+			} else {
+				if (dn >= eom) {
+					errno = EMSGSIZE;
+					return (-1);
+				}
+				*dn++ = (char)c;
+			}
+		}
+	}
+	if (dn == dst) {
+		if (dn >= eom) {
+			errno = EMSGSIZE;
+			return (-1);
+		}
+		*dn++ = '.';
+	}
+	if (dn >= eom) {
+		errno = EMSGSIZE;
+		return (-1);
+	}
+	*dn++ = '\0';
+	return (dn - dst);
+}
+
+/*
+ * MRns_name_pton(src, dst, dstsiz)
+ *	Convert a ascii string into an encoded domain name as per RFC1035.
+ * return:
+ *	-1 if it fails
+ *	1 if string was fully qualified
+ *	0 is string was not fully qualified
+ * notes:
+ *	Enforces label and domain length limits.
+ */
+
+int
+MRns_name_pton(const char *src, u_char *dst, size_t dstsiz) {
+	u_char *label, *bp, *eom;
+	int c, n, escaped;
+	char *cp;
+
+	escaped = 0;
+	bp = dst;
+	eom = dst + dstsiz;
+	label = bp++;
+
+	while ((c = *src++) != 0) {
+		if (escaped) {
+			if ((cp = strchr(digits, c)) != NULL) {
+				n = (cp - digits) * 100;
+				if ((c = *src++) == 0 ||
+				    (cp = strchr(digits, c)) == NULL) {
+					errno = EMSGSIZE;
+					return (-1);
+				}
+				n += (cp - digits) * 10;
+				if ((c = *src++) == 0 ||
+				    (cp = strchr(digits, c)) == NULL) {
+					errno = EMSGSIZE;
+					return (-1);
+				}
+				n += (cp - digits);
+				if (n > 255) {
+					errno = EMSGSIZE;
+					return (-1);
+				}
+				c = n;
+			}
+			escaped = 0;
+		} else if (c == '\\') {
+			escaped = 1;
+			continue;
+		} else if (c == '.') {
+			c = (bp - label - 1);
+			if ((c & NS_CMPRSFLGS) != 0) {	/* Label too big. */
+				errno = EMSGSIZE;
+				return (-1);
+			}
+			if (label >= eom) {
+				errno = EMSGSIZE;
+				return (-1);
+			}
+			*label = c;
+			/* Fully qualified ? */
+			if (*src == '\0') {
+				if (c != 0) {
+					if (bp >= eom) {
+						errno = EMSGSIZE;
+						return (-1);
+					}
+					*bp++ = '\0';
+				}
+				if ((bp - dst) > MAXCDNAME) {
+					errno = EMSGSIZE;
+					return (-1);
+				}
+				return (1);
+			}
+			if (c == 0 || *src == '.') {
+				errno = EMSGSIZE;
+				return (-1);
+			}
+			label = bp++;
+			continue;
+		}
+		if (bp >= eom) {
+			errno = EMSGSIZE;
+			return (-1);
+		}
+		*bp++ = (u_char)c;
+	}
+	c = (bp - label - 1);
+	if ((c & NS_CMPRSFLGS) != 0) {		/* Label too big. */
+		errno = EMSGSIZE;
+		return (-1);
+	}
+	if (label >= eom) {
+		errno = EMSGSIZE;
+		return (-1);
+	}
+	*label = c;
+	if (c != 0) {
+		if (bp >= eom) {
+			errno = EMSGSIZE;
+			return (-1);
+		}
+		*bp++ = 0;
+	}
+	if ((bp - dst) > MAXCDNAME) {	/* src too big */
+		errno = EMSGSIZE;
+		return (-1);
+	}
+	return (0);
+}
+
+/*
+ * MRns_name_ntol(src, dst, dstsiz)
+ *	Convert a network strings labels into all lowercase.
+ * return:
+ *	Number of bytes written to buffer, or -1 (with errno set)
+ * notes:
+ *	Enforces label and domain length limits.
+ */
+
+int
+MRns_name_ntol(const u_char *src, u_char *dst, size_t dstsiz) {
+	const u_char *cp;
+	u_char *dn, *eom;
+	u_char c;
+	u_int n;
+
+	cp = src;
+	dn = dst;
+	eom = dst + dstsiz;
+
+	if (dn >= eom) {
+		errno = EMSGSIZE;
+		return (-1);
+	}
+	while ((n = *cp++) != 0) {
+		if ((n & NS_CMPRSFLGS) != 0) {
+			/* Some kind of compression pointer. */
+			errno = EMSGSIZE;
+			return (-1);
+		}
+		*dn++ = n;
+		if (dn + n >= eom) {
+			errno = EMSGSIZE;
+			return (-1);
+		}
+		for ((void)NULL; n > 0; n--) {
+			c = *cp++;
+			if (isupper(c))
+				*dn++ = tolower(c);
+			else
+				*dn++ = c;
+		}
+	}
+	*dn++ = '\0';
+	return (dn - dst);
+}
+
+/*
+ * MRns_name_unpack(msg, eom, src, dst, dstsiz)
+ *	Unpack a domain name from a message, source may be compressed.
+ * return:
+ *	-1 if it fails, or consumed octets if it succeeds.
+ */
+int
+MRns_name_unpack(const u_char *msg, const u_char *eom, const u_char *src,
+	         u_char *dst, size_t dstsiz)
+{
+	const u_char *srcp, *dstlim;
+	u_char *dstp;
+	unsigned n;
+	int len;
+	int checked;
+
+	len = -1;
+	checked = 0;
+	dstp = dst;
+	srcp = src;
+	dstlim = dst + dstsiz;
+	if (srcp < msg || srcp >= eom) {
+		errno = EMSGSIZE;
+		return (-1);
+	}
+	/* Fetch next label in domain name. */
+	while ((n = *srcp++) != 0) {
+		/* Check for indirection. */
+		switch (n & NS_CMPRSFLGS) {
+		case 0:
+			/* Limit checks. */
+			if (dstp + n + 1 >= dstlim || srcp + n >= eom) {
+				errno = EMSGSIZE;
+				return (-1);
+			}
+			checked += n + 1;
+			*dstp++ = n;
+			memcpy(dstp, srcp, n);
+			dstp += n;
+			srcp += n;
+			break;
+
+		case NS_CMPRSFLGS:
+			if (srcp >= eom) {
+				errno = EMSGSIZE;
+				return (-1);
+			}
+			if (len < 0)
+				len = srcp - src + 1;
+			srcp = msg + (((n & 0x3f) << 8) | (*srcp & 0xff));
+			if (srcp < msg || srcp >= eom) {  /* Out of range. */
+				errno = EMSGSIZE;
+				return (-1);
+			}
+			checked += 2;
+			/*
+			 * Check for loops in the compressed name;
+			 * if we've looked at the whole message,
+			 * there must be a loop.
+			 */
+			if (checked >= eom - msg) {
+				errno = EMSGSIZE;
+				return (-1);
+			}
+			break;
+
+		default:
+			errno = EMSGSIZE;
+			return (-1);			/* flag error */
+		}
+	}
+	*dstp = '\0';
+	if (len < 0)
+		len = srcp - src;
+	return (len);
+}
+
+/*
+ * MRns_name_pack(src, dst, dstsiz, dnptrs, lastdnptr)
+ *	Pack domain name 'domain' into 'comp_dn'.
+ * return:
+ *	Size of the compressed name, or -1.
+ * notes:
+ *	'dnptrs' is an array of pointers to previous compressed names.
+ *	dnptrs[0] is a pointer to the beginning of the message. The array
+ *	ends with NULL.
+ *	'lastdnptr' is a pointer to the end of the array pointed to
+ *	by 'dnptrs'.
+ * Side effects:
+ *	The list of pointers in dnptrs is updated for labels inserted into
+ *	the message as we compress the name.  If 'dnptr' is NULL, we don't
+ *	try to compress names. If 'lastdnptr' is NULL, we don't update the
+ *	list.
+ */
+int
+MRns_name_pack(const u_char *src, u_char *dst, unsigned dstsiz,
+	       const u_char **dnptrs, const u_char **lastdnptr)
+{
+	u_char *dstp;
+	const u_char **cpp, **lpp, *eob, *msg;
+	const u_char *srcp;
+	unsigned n;
+	int l;
+
+	srcp = src;
+	dstp = dst;
+	eob = dstp + dstsiz;
+	lpp = cpp = NULL;
+	if (dnptrs != NULL) {
+		if ((msg = *dnptrs++) != NULL) {
+			for (cpp = dnptrs; *cpp != NULL; cpp++)
+				(void)NULL;
+			lpp = cpp;	/* end of list to search */
+		}
+	} else
+		msg = NULL;
+
+	/* make sure the domain we are about to add is legal */
+	l = 0;
+	do {
+		n = *srcp;
+		if ((n & NS_CMPRSFLGS) != 0) {
+			errno = EMSGSIZE;
+			return (-1);
+		}
+		l += n + 1;
+		if (l > MAXCDNAME) {
+			errno = EMSGSIZE;
+			return (-1);
+		}
+		srcp += n + 1;
+	} while (n != 0);
+
+	/* from here on we need to reset compression pointer array on error */
+	srcp = src;
+	do {
+		/* Look to see if we can use pointers. */
+		n = *srcp;
+		if (n != 0 && msg != NULL) {
+			l = dn_find(srcp, msg, (const u_char * const *)dnptrs,
+				    (const u_char * const *)lpp);
+			if (l >= 0) {
+				if (dstp + 1 >= eob) {
+					goto cleanup;
+				}
+				*dstp++ = (l >> 8) | NS_CMPRSFLGS;
+				*dstp++ = l % 256;
+				return (dstp - dst);
+			}
+			/* Not found, save it. */
+			if (lastdnptr != NULL && cpp < lastdnptr - 1 &&
+			    (dstp - msg) < 0x4000) {
+				*cpp++ = dstp;
+				*cpp = NULL;
+			}
+		}
+		/* copy label to buffer */
+		if (n & NS_CMPRSFLGS) {		/* Should not happen. */
+			goto cleanup;
+		}
+		if (dstp + 1 + n >= eob) {
+			goto cleanup;
+		}
+		memcpy(dstp, srcp, n + 1);
+		srcp += n + 1;
+		dstp += n + 1;
+	} while (n != 0);
+
+	if (dstp > eob) {
+cleanup:
+		if (msg != NULL)
+			*lpp = NULL;
+		errno = EMSGSIZE;
+		return (-1);
+	} 
+	return (dstp - dst);
+}
+
+/*
+ * MRns_name_uncompress(msg, eom, src, dst, dstsiz)
+ *	Expand compressed domain name to presentation format.
+ * return:
+ *	Number of bytes read out of `src', or -1 (with errno set).
+ * note:
+ *	Root domain returns as "." not "".
+ */
+int
+MRns_name_uncompress(const u_char *msg, const u_char *eom, const u_char *src,
+		     char *dst, size_t dstsiz)
+{
+	u_char tmp[NS_MAXCDNAME];
+	int n;
+	
+	if ((n = MRns_name_unpack(msg, eom, src, tmp, sizeof tmp)) == -1)
+		return (-1);
+	if (MRns_name_ntop(tmp, dst, dstsiz) == -1)
+		return (-1);
+	return (n);
+}
+
+/*
+ * MRns_name_compress(src, dst, dstsiz, dnptrs, lastdnptr)
+ *	Compress a domain name into wire format, using compression pointers.
+ * return:
+ *	Number of bytes consumed in `dst' or -1 (with errno set).
+ * notes:
+ *	'dnptrs' is an array of pointers to previous compressed names.
+ *	dnptrs[0] is a pointer to the beginning of the message.
+ *	The list ends with NULL.  'lastdnptr' is a pointer to the end of the
+ *	array pointed to by 'dnptrs'. Side effect is to update the list of
+ *	pointers for labels inserted into the message as we compress the name.
+ *	If 'dnptr' is NULL, we don't try to compress names. If 'lastdnptr'
+ *	is NULL, we don't update the list.
+ */
+int
+MRns_name_compress(const char *src, u_char *dst, size_t dstsiz,
+		 const u_char **dnptrs, const u_char **lastdnptr)
+{
+	u_char tmp[NS_MAXCDNAME];
+
+	if (MRns_name_pton(src, tmp, sizeof tmp) == -1)
+		return (-1);
+	return (MRns_name_pack(tmp, dst, dstsiz, dnptrs, lastdnptr));
+}
+
+/*
+ * MRns_name_skip(ptrptr, eom)
+ *	Advance *ptrptr to skip over the compressed name it points at.
+ * return:
+ *	0 on success, -1 (with errno set) on failure.
+ */
+int
+MRns_name_skip(const u_char **ptrptr, const u_char *eom) {
+	const u_char *cp;
+	u_int n;
+
+	cp = *ptrptr;
+	while (cp < eom && (n = *cp++) != 0) {
+		/* Check for indirection. */
+		switch (n & NS_CMPRSFLGS) {
+		case 0:			/* normal case, n == len */
+			cp += n;
+			continue;
+		case NS_CMPRSFLGS:	/* indirection */
+			cp++;
+			break;
+		default:		/* illegal type */
+			errno = EMSGSIZE;
+			return (-1);
+		}
+		break;
+	}
+	if (cp > eom) {
+		errno = EMSGSIZE;
+		return (-1);
+	}
+	*ptrptr = cp;
+	return (0);
+}
+
+/* Private. */
+
+/*
+ * special(ch)
+ *	Thinking in noninternationalized USASCII (per the DNS spec),
+ *	is this characted special ("in need of quoting") ?
+ * return:
+ *	boolean.
+ */
+static int
+special(int ch) {
+	switch (ch) {
+	case 0x22: /* '"' */
+	case 0x2E: /* '.' */
+	case 0x3B: /* ';' */
+	case 0x5C: /* '\\' */
+	/* Special modifiers in zone files. */
+	case 0x40: /* '@' */
+	case 0x24: /* '$' */
+		return (1);
+	default:
+		return (0);
+	}
+}
+
+/*
+ * printable(ch)
+ *	Thinking in noninternationalized USASCII (per the DNS spec),
+ *	is this character visible and not a space when printed ?
+ * return:
+ *	boolean.
+ */
+static int
+printable(int ch) {
+	return (ch > 0x20 && ch < 0x7f);
+}
+
+/*
+ *	Thinking in noninternationalized USASCII (per the DNS spec),
+ *	convert this character to lower case if it's upper case.
+ */
+static int
+mklower(int ch) {
+	if (ch >= 0x41 && ch <= 0x5A)
+		return (ch + 0x20);
+	return (ch);
+}
+
+/*
+ * dn_find(domain, msg, dnptrs, lastdnptr)
+ *	Search for the counted-label name in an array of compressed names.
+ * return:
+ *	offset from msg if found, or -1.
+ * notes:
+ *	dnptrs is the pointer to the first name on the list,
+ *	not the pointer to the start of the message.
+ */
+static int
+dn_find(const u_char *domain, const u_char *msg,
+	const u_char * const *dnptrs,
+	const u_char * const *lastdnptr)
+{
+	const u_char *dn, *cp, *sp;
+	const u_char * const *cpp;
+	u_int n;
+
+	for (cpp = dnptrs; cpp < lastdnptr; cpp++) {
+		dn = domain;
+		sp = cp = *cpp;
+		while ((n = *cp++) != 0) {
+			/*
+			 * check for indirection
+			 */
+			switch (n & NS_CMPRSFLGS) {
+			case 0:			/* normal case, n == len */
+				if (n != *dn++)
+					goto next;
+				for ((void)NULL; n > 0; n--)
+					if (mklower(*dn++) != mklower(*cp++))
+						goto next;
+				/* Is next root for both ? */
+				if (*dn == '\0' && *cp == '\0')
+					return (sp - msg);
+				if (*dn)
+					continue;
+				goto next;
+
+			case NS_CMPRSFLGS:	/* indirection */
+				cp = msg + (((n & 0x3f) << 8) | *cp);
+				break;
+
+			default:	/* illegal type */
+				errno = EMSGSIZE;
+				return (-1);
+			}
+		}
+ next: ;
+	}
+	errno = ENOENT;
+	return (-1);
+}
+
+/*!
+ * \brief Creates a string of comma-separated domain-names from a
+ * compressed list
+ *
+ * Produces a null-terminated string of comma-separated domain-names from
+ * a buffer containing a compressed list of domain-names. The names will
+ * be dotted and without enclosing quotes. For example:
+ * If a compressed list contains the follwoing two domain names:
+ *
+ *  a. one.two.com
+ *  b. three.four.com
+ *
+ * The compressed data will look like this:
+ *
+ *  03 6f 6e 65 03 74 77 6f 03 63 6f 6d 00 05 74 68
+ *  72 65 65 04 66 6f 75 72 c0 08
+ *
+ * and will decompress into:
+ *
+ *  one.two.com,three.four.com
+ *
+ * \param  buf - buffer containing the compressed list of domain-names
+ * \param  buflen - length of compressed list of domain-names
+ * \param  dst_buf - buffer to receive the decompressed list
+ * \param  dst_size - size of the destination buffer
+ *
+ * \return the length of the decompressed string when successful, -1 on
+ * error.
+ */
+int MRns_name_uncompress_list(const unsigned char* buf, int buflen,
+			      char* dst_buf, size_t dst_size)
+{
+	const unsigned char* src = buf;
+	char* dst = dst_buf;
+	int consumed = 1;
+	int dst_remaining = dst_size;
+	int added_len = 0;
+	int first_pass = 1;
+
+	if (!buf || buflen == 0 || *buf == 0x00) {
+		/* nothing to do */
+		*dst = 0;
+		return (0);
+	}
+
+	while ((consumed > 0) && (src < (buf + buflen)))
+	{
+		if (dst_remaining <= 0) {
+			errno = EMSGSIZE;
+			return (-1);
+		}
+
+		if (!first_pass) {
+			*dst++ = ',';
+			*dst = '\0';
+			dst_remaining--;
+		}
+
+		consumed = MRns_name_uncompress(buf, buf + buflen, src,
+						dst, dst_remaining);
+		if (consumed < 0) {
+			return (-1);
+		}
+
+		src += consumed;
+		added_len = strlen(dst);
+		dst_remaining -= added_len;
+		dst += added_len;
+		first_pass = 0;
+	}
+	*dst='\0';
+
+	/* return the length of the uncompressed list string */
+	return (strlen(dst_buf));
+}
+
+/*!
+ * \brief Creates a compressed list from a string of comma-separated
+ * domain-names
+ *
+ * Produces a buffer containing a compressed data version of a list of
+ * domain-names extracted from a comma-separated string. Given a string
+ * containing:
+ *
+ *  one.two.com,three.four.com
+ *
+ * It will compress this into:
+ *
+ *  03 6f 6e 65 03 74 77 6f 03 63 6f 6d 00 05 74 68
+ *  72 65 65 04 66 6f 75 72 c0 08
+ *
+ * \param  buf - buffer containing the uncompressed string of domain-names
+ * \param  buflen - length of uncompressed string of domain-names
+ * \param  compbuf - buffer to receive the compressed list
+ * \param  compbuf_size - size of the compression buffer
+ *
+ * \return the length of the compressed data when successful, -1 on error.
+ */
+int MRns_name_compress_list(const char* buf, int buflen,
+	unsigned char* compbuf, size_t compbuf_size)
+{
+	char cur_name[NS_MAXCDNAME];
+	const unsigned char *dnptrs[256], **lastdnptr;
+	const char* src;
+	const char* src_end;
+	unsigned clen = 0;
+	int result = 0;
+
+	memset(compbuf, 0, compbuf_size);
+	memset(dnptrs, 0, sizeof(dnptrs));
+	dnptrs[0] = compbuf;
+	lastdnptr = &dnptrs[255];
+
+	src = buf;
+	src_end = buf + buflen;
+	while (src < src_end) {
+		char *comma = strchr(src, ',');
+		int copylen = ((comma != NULL) ? comma - src : strlen(src));
+		if (copylen > (sizeof(cur_name) - 1)) {
+			errno = EMSGSIZE;
+			return (-1);
+		}
+
+		memcpy(cur_name, src, copylen);
+		cur_name[copylen] = '\0';
+		src += copylen + 1;
+
+		result = MRns_name_compress(cur_name, compbuf + clen,
+					    compbuf_size - clen,
+					    dnptrs, lastdnptr);
+
+		if (result < 0) {
+			return (-1);
+		}
+
+		clen += result;
+	}
+
+	/* return size of compressed list */
+	return(clen);
+}