1 files changed, 475 insertions, 0 deletions

diff --git a/src/lib/libc/net/res_comp.c b/src/lib/libc/net/res_comp.c
new file mode 100644
index 0000000000..69a6ce0abb
--- /dev/null
+++ b/src/lib/libc/net/res_comp.c
@@ -0,0 +1,475 @@
+/*      $OpenBSD: res_comp.c,v 1.14 2008/04/16 22:35:23 deraadt Exp $   */
+
+/*
+ * ++Copyright++ 1985, 1993
+ * -
+ * Copyright (c) 1985, 1993
+ *    The Regents of the University of California.  All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * -
+ * Portions Copyright (c) 1993 by Digital Equipment Corporation.
+ * 
+ * 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, and that
+ * the name of Digital Equipment Corporation not be used in advertising or
+ * publicity pertaining to distribution of the document or software without
+ * specific, written prior permission.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
+ * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
+ * CORPORATION 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.
+ * -
+ * --Copyright--
+ */
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <netinet/in.h>
+#include <arpa/nameser.h>
+
+#include <stdio.h>
+#include <resolv.h>
+#include <ctype.h>
+
+#include <unistd.h>
+#include <string.h>
+
+static int dn_find(u_char *, u_char *, u_char **, u_char **);
+
+/*
+ * Expand compressed domain name 'comp_dn' to full domain name.
+ * 'msg' is a pointer to the begining of the message,
+ * 'eomorig' points to the first location after the message,
+ * 'exp_dn' is a pointer to a buffer of size 'length' for the result.
+ * Return size of compressed name or -1 if there was an error.
+ */
+int
+dn_expand(const u_char *msg, const u_char *eomorig, const u_char *comp_dn,
+    char *exp_dn, int length)
+{
+        const u_char *cp;
+        char *dn;
+        int n, c;
+        char *eom;
+        int len = -1, checked = 0;
+
+        dn = exp_dn;
+        cp = comp_dn;
+        if (length > MAXHOSTNAMELEN-1)
+                length = MAXHOSTNAMELEN-1;
+        eom = exp_dn + length;
+        /*
+         * fetch next label in domain name
+         */
+        while ((n = *cp++)) {
+                /*
+                 * Check for indirection
+                 */
+                switch (n & INDIR_MASK) {
+                case 0:
+                        if (dn != exp_dn) {
+                                if (dn >= eom)
+                                        return (-1);
+                                *dn++ = '.';
+                        }
+                        if (dn+n >= eom)
+                                return (-1);
+                        checked += n + 1;
+                        while (--n >= 0) {
+                                if (((c = *cp++) == '.') || (c == '\\')) {
+                                        if (dn + n + 2 >= eom)
+                                                return (-1);
+                                        *dn++ = '\\';
+                                }
+                                *dn++ = c;
+                                if (cp >= eomorig)      /* out of range */
+                                        return (-1);
+                        }
+                        break;
+
+                case INDIR_MASK:
+                        if (len < 0)
+                                len = cp - comp_dn + 1;
+                        cp = msg + (((n & 0x3f) << 8) | (*cp & 0xff));
+                        if (cp < msg || cp >= eomorig)  /* out of range */
+                                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 >= eomorig - msg)
+                                return (-1);
+                        break;
+
+                default:
+                        return (-1);                    /* flag error */
+                }
+        }
+        *dn = '\0';
+        if (len < 0)
+                len = cp - comp_dn;
+        return (len);
+}
+
+/*
+ * Compress domain name 'exp_dn' into 'comp_dn'.
+ * Return the size of the compressed name or -1.
+ * 'length' is the size of the array pointed to by 'comp_dn'.
+ * 'dnptrs' is a list 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 arrary 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
+dn_comp(const char *exp_dn, u_char *comp_dn, int length, u_char **dnptrs,
+    u_char **lastdnptr)
+{
+        u_char *cp, *dn;
+        int c, l;
+        u_char **cpp, **lpp, *sp, *eob;
+        u_char *msg;
+
+        dn = (u_char *)exp_dn;
+        cp = comp_dn;
+        eob = cp + length;
+        lpp = cpp = NULL;
+        if (dnptrs != NULL) {
+                if ((msg = *dnptrs++) != NULL) {
+                        for (cpp = dnptrs; *cpp != NULL; cpp++)
+                                ;
+                        lpp = cpp;      /* end of list to search */
+                }
+        } else
+                msg = NULL;
+        for (c = *dn++; c != '\0'; ) {
+                /* look to see if we can use pointers */
+                if (msg != NULL) {
+                        if ((l = dn_find(dn-1, msg, dnptrs, lpp)) >= 0) {
+                                if (cp+1 >= eob)
+                                        return (-1);
+                                *cp++ = (l >> 8) | INDIR_MASK;
+                                *cp++ = l % 256;
+                                return (cp - comp_dn);
+                        }
+                        /* not found, save it */
+                        if (lastdnptr != NULL && cpp < lastdnptr-1) {
+                                *cpp++ = cp;
+                                *cpp = NULL;
+                        }
+                }
+                sp = cp++;      /* save ptr to length byte */
+                do {
+                        if (c == '.') {
+                                c = *dn++;
+                                break;
+                        }
+                        if (c == '\\') {
+                                if ((c = *dn++) == '\0')
+                                        break;
+                        }
+                        if (cp >= eob) {
+                                if (msg != NULL)
+                                        *lpp = NULL;
+                                return (-1);
+                        }
+                        *cp++ = c;
+                } while ((c = *dn++) != '\0');
+                /* catch trailing '.'s but not '..' */
+                if ((l = cp - sp - 1) == 0 && c == '\0') {
+                        cp--;
+                        break;
+                }
+                if (l <= 0 || l > MAXLABEL) {
+                        if (msg != NULL)
+                                *lpp = NULL;
+                        return (-1);
+                }
+                *sp = l;
+        }
+        if (cp >= eob) {
+                if (msg != NULL)
+                        *lpp = NULL;
+                return (-1);
+        }
+        *cp++ = '\0';
+        return (cp - comp_dn);
+}
+
+/*
+ * Skip over a compressed domain name. Return the size or -1.
+ */
+int
+__dn_skipname(const u_char *comp_dn, const u_char *eom)
+{
+        const u_char *cp;
+        int n;
+
+        cp = comp_dn;
+        while (cp < eom && (n = *cp++)) {
+                /*
+                 * check for indirection
+                 */
+                switch (n & INDIR_MASK) {
+                case 0:                 /* normal case, n == len */
+                        cp += n;
+                        continue;
+                case INDIR_MASK:        /* indirection */
+                        cp++;
+                        break;
+                default:                /* illegal type */
+                        return (-1);
+                }
+                break;
+        }
+        if (cp > eom)
+                return (-1);
+        return (cp - comp_dn);
+}
+
+static int
+mklower(int ch)
+{
+        if (isascii(ch) && isupper(ch))
+                return (tolower(ch));
+        return (ch);
+}
+
+/*
+ * Search for expanded name from a list of previously compressed names.
+ * Return the offset from msg if found or -1.
+ * dnptrs is the pointer to the first name on the list,
+ * not the pointer to the start of the message.
+ */
+static int
+dn_find(u_char *exp_dn, u_char *msg, u_char **dnptrs, u_char **lastdnptr)
+{
+        u_char *dn, *cp, **cpp;
+        int n;
+        u_char *sp;
+
+        for (cpp = dnptrs; cpp < lastdnptr; cpp++) {
+                dn = exp_dn;
+                sp = cp = *cpp;
+                while ((n = *cp++)) {
+                        /*
+                         * check for indirection
+                         */
+                        switch (n & INDIR_MASK) {
+                        case 0:         /* normal case, n == len */
+                                while (--n >= 0) {
+                                        if (*dn == '.')
+                                                goto next;
+                                        if (*dn == '\\')
+                                                dn++;
+                                        if (mklower(*dn++) != mklower(*cp++))
+                                                goto next;
+                                }
+                                if ((n = *dn++) == '\0' && *cp == '\0')
+                                        return (sp - msg);
+                                if (n == '.')
+                                        continue;
+                                goto next;
+
+                        case INDIR_MASK:        /* indirection */
+                                cp = msg + (((n & 0x3f) << 8) | *cp);
+                                break;
+
+                        default:        /* illegal type */
+                                return (-1);
+                        }
+                }
+                if (*dn == '\0')
+                        return (sp - msg);
+        next:   ;
+        }
+        return (-1);
+}
+
+/*
+ * Verify that a domain name uses an acceptable character set.
+ */
+
+/*
+ * Note the conspicuous absence of ctype macros in these definitions.  On
+ * non-ASCII hosts, we can't depend on string literals or ctype macros to
+ * tell us anything about network-format data.  The rest of the BIND system
+ * is not careful about this, but for some reason, we're doing it right here.
+ */
+#define PERIOD 0x2e
+#define hyphenchar(c) ((c) == 0x2d)
+#define bslashchar(c) ((c) == 0x5c)
+#define underscorechar(c) ((c) == 0x5f)
+#define periodchar(c) ((c) == PERIOD)
+#define asterchar(c) ((c) == 0x2a)
+#define alphachar(c) (((c) >= 0x41 && (c) <= 0x5a) \
+                   || ((c) >= 0x61 && (c) <= 0x7a))
+#define digitchar(c) ((c) >= 0x30 && (c) <= 0x39)
+
+#define borderchar(c) (alphachar(c) || digitchar(c))
+#define middlechar(c) (borderchar(c) || hyphenchar(c) || underscorechar(c))
+#define domainchar(c) ((c) > 0x20 && (c) < 0x7f)
+
+int
+res_hnok(const char *dn)
+{
+        int pch = PERIOD, ch = *dn++;
+
+        while (ch != '\0') {
+                int nch = *dn++;
+
+                if (periodchar(ch)) {
+                        ;
+                } else if (periodchar(pch)) {
+                        if (!borderchar(ch))
+                                return (0);
+                } else if (periodchar(nch) || nch == '\0') {
+                        if (!borderchar(ch))
+                                return (0);
+                } else {
+                        if (!middlechar(ch))
+                                return (0);
+                }
+                pch = ch, ch = nch;
+        }
+        return (1);
+}
+
+/*
+ * hostname-like (A, MX, WKS) owners can have "*" as their first label
+ * but must otherwise be as a host name.
+ */
+int
+res_ownok(const char *dn)
+{
+        if (asterchar(dn[0])) {
+                if (periodchar(dn[1]))
+                        return (res_hnok(dn+2));
+                if (dn[1] == '\0')
+                        return (1);
+        }
+        return (res_hnok(dn));
+}
+
+/*
+ * SOA RNAMEs and RP RNAMEs can have any printable character in their first
+ * label, but the rest of the name has to look like a host name.
+ */
+int
+res_mailok(const char *dn)
+{
+        int ch, escaped = 0;
+
+        /* "." is a valid missing representation */
+        if (*dn == '\0')
+                return(1);
+
+        /* otherwise <label>.<hostname> */
+        while ((ch = *dn++) != '\0') {
+                if (!domainchar(ch))
+                        return (0);
+                if (!escaped && periodchar(ch))
+                        break;
+                if (escaped)
+                        escaped = 0;
+                else if (bslashchar(ch))
+                        escaped = 1;
+        }
+        if (periodchar(ch))
+                return (res_hnok(dn));
+        return(0);
+}
+
+/*
+ * This function is quite liberal, since RFC 1034's character sets are only
+ * recommendations.
+ */
+int
+res_dnok(const char *dn)
+{
+        int ch;
+
+        while ((ch = *dn++) != '\0')
+                if (!domainchar(ch))
+                        return (0);
+        return (1);
+}
+
+/*
+ * Routines to insert/extract short/long's.
+ */
+
+u_int16_t
+_getshort(const u_char *msgp)
+{
+        u_int16_t u;
+
+        GETSHORT(u, msgp);
+        return (u);
+}
+
+#ifdef NeXT
+/*
+ * nExt machines have some funky library conventions, which we must maintain.
+ */
+u_int16_t
+res_getshort(msgp)
+        const u_char *msgp;
+{
+        return (_getshort(msgp));
+}
+#endif
+
+u_int32_t
+_getlong(const u_char *msgp)
+{
+        u_int32_t u;
+
+        GETLONG(u, msgp);
+        return (u);
+}
+
+void
+__putshort(u_int16_t s, u_char *msgp)
+{
+        PUTSHORT(s, msgp);
+}
+
+void
+__putlong(u_int32_t l, u_char *msgp)
+{
+        PUTLONG(l, msgp);
+}