diff options
Diffstat (limited to 'contrib/bind/lib/nameser/ns_name.c')
| -rw-r--r-- | contrib/bind/lib/nameser/ns_name.c | 963 |
1 files changed, 0 insertions, 963 deletions
diff --git a/contrib/bind/lib/nameser/ns_name.c b/contrib/bind/lib/nameser/ns_name.c deleted file mode 100644 index c57ac3b..0000000 --- a/contrib/bind/lib/nameser/ns_name.c +++ /dev/null @@ -1,963 +0,0 @@ -/* - * 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: ns_name.c,v 8.20 2003/04/03 06:00:07 marka Exp $"; -#endif - -#include "port_before.h" - -#include <sys/types.h> - -#include <netinet/in.h> -#include <arpa/nameser.h> - -#include <errno.h> -#include <resolv.h> -#include <string.h> -#include <ctype.h> -#include <stdlib.h> -#include <limits.h> - -#include "port_after.h" - -#ifdef SPRINTF_CHAR -# define SPRINTF(x) strlen(sprintf/**/x) -#else -# define SPRINTF(x) ((size_t)sprintf x) -#endif - -#define NS_TYPE_ELT 0x40 /* EDNS0 extended label type */ -#define DNS_LABELTYPE_BITSTRING 0x41 - -/* Data. */ - -static const char digits[] = "0123456789"; - -static const char digitvalue[256] = { - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*16*/ - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*32*/ - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*48*/ - 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, /*64*/ - -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*80*/ - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*96*/ - -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*112*/ - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*128*/ - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, - -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*256*/ -}; - -/* 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 *); -static int encode_bitsring(const char **, const char *, - char **, char **, const char *); -static int labellen(const u_char *); -static int decode_bitstring(const char **, char *, const char *); - -/* Public. */ - -/* - * ns_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 -ns_name_ntop(const u_char *src, char *dst, size_t dstsiz) -{ - const u_char *cp; - char *dn, *eom; - u_char c; - u_int n; - int l; - - cp = src; - dn = dst; - eom = dst + dstsiz; - - while ((n = *cp++) != 0) { - if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) { - /* Some kind of compression pointer. */ - errno = EMSGSIZE; - return (-1); - } - if (dn != dst) { - if (dn >= eom) { - errno = EMSGSIZE; - return (-1); - } - *dn++ = '.'; - } - if ((l = labellen(cp - 1)) < 0) { - errno = EMSGSIZE; /* XXX */ - return(-1); - } - if (dn + l >= eom) { - errno = EMSGSIZE; - return (-1); - } - if ((n & NS_CMPRSFLGS) == NS_TYPE_ELT) { - int m; - - if (n != DNS_LABELTYPE_BITSTRING) { - /* XXX: labellen should reject this case */ - errno = EINVAL; - return(-1); - } - if ((m = decode_bitstring((const char **)&cp, dn, eom)) < 0) - { - errno = EMSGSIZE; - return(-1); - } - dn += m; - continue; - } - for ((void)NULL; l > 0; l--) { - 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); -} - -/* - * ns_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 -ns_name_pton(const char *src, u_char *dst, size_t dstsiz) -{ - u_char *label, *bp, *eom; - int c, n, escaped, e = 0; - char *cp; - - escaped = 0; - bp = dst; - eom = dst + dstsiz; - label = bp++; - - while ((c = *src++) != 0) { - if (escaped) { - if (c == '[') { /* start a bit string label */ - if ((cp = strchr(src, ']')) == NULL) { - errno = EINVAL; /* ??? */ - return(-1); - } - if ((e = encode_bitsring(&src, - cp + 2, - (char **)&label, - (char **)&bp, - (const char *)eom)) - != 0) { - errno = e; - return(-1); - } - escaped = 0; - label = bp++; - if ((c = *src++) == 0) - goto done; - else if (c != '.') { - errno = EINVAL; - return(-1); - } - continue; - } - else 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); - } - done: - 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); -} - -/* - * ns_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 -ns_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; - int l; - - cp = src; - dn = dst; - eom = dst + dstsiz; - - if (dn >= eom) { - errno = EMSGSIZE; - return (-1); - } - while ((n = *cp++) != 0) { - if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) { - /* Some kind of compression pointer. */ - errno = EMSGSIZE; - return (-1); - } - *dn++ = n; - if ((l = labellen(cp - 1)) < 0) { - errno = EMSGSIZE; - return (-1); - } - if (dn + l >= eom) { - errno = EMSGSIZE; - return (-1); - } - for ((void)NULL; l > 0; l--) { - c = *cp++; - if (isupper(c)) - *dn++ = tolower(c); - else - *dn++ = c; - } - } - *dn++ = '\0'; - return (dn - dst); -} - -/* - * ns_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 -ns_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; - int n, len, checked, l; - - 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: - case NS_TYPE_ELT: - /* Limit checks. */ - if ((l = labellen(srcp - 1)) < 0) { - errno = EMSGSIZE; - return(-1); - } - if (dstp + l + 1 >= dstlim || srcp + l >= eom) { - errno = EMSGSIZE; - return (-1); - } - checked += l + 1; - *dstp++ = n; - memcpy(dstp, srcp, l); - dstp += l; - srcp += l; - 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); -} - -/* - * ns_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 -ns_name_pack(const u_char *src, u_char *dst, int dstsiz, - const u_char **dnptrs, const u_char **lastdnptr) -{ - u_char *dstp; - const u_char **cpp, **lpp, *eob, *msg; - const u_char *srcp; - int n, l, first = 1; - - 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 { - int l0; - - n = *srcp; - if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) { - errno = EMSGSIZE; - return (-1); - } - if ((l0 = labellen(srcp)) < 0) { - errno = EINVAL; - return(-1); - } - l += l0 + 1; - if (l > MAXCDNAME) { - errno = EMSGSIZE; - return (-1); - } - srcp += l0 + 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 && first) { - *cpp++ = dstp; - *cpp = NULL; - first = 0; - } - } - /* copy label to buffer */ - if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) { - /* Should not happen. */ - goto cleanup; - } - n = labellen(srcp); - 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); -} - -/* - * ns_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 -ns_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 = ns_name_unpack(msg, eom, src, tmp, sizeof tmp)) == -1) - return (-1); - if (ns_name_ntop(tmp, dst, dstsiz) == -1) - return (-1); - return (n); -} - -/* - * ns_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 -ns_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 (ns_name_pton(src, tmp, sizeof tmp) == -1) - return (-1); - return (ns_name_pack(tmp, dst, dstsiz, dnptrs, lastdnptr)); -} - -/* - * Reset dnptrs so that there are no active references to pointers at or - * after src. - */ -void -ns_name_rollback(const u_char *src, const u_char **dnptrs, - const u_char **lastdnptr) -{ - while (dnptrs < lastdnptr && *dnptrs != NULL) { - if (*dnptrs >= src) { - *dnptrs = NULL; - break; - } - dnptrs++; - } -} - -/* - * ns_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 -ns_name_skip(const u_char **ptrptr, const u_char *eom) -{ - const u_char *cp; - u_int n; - int l; - - 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_TYPE_ELT: /* EDNS0 extended label */ - if ((l = labellen(cp - 1)) < 0) { - errno = EMSGSIZE; /* XXX */ - return(-1); - } - cp += l; - 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: /* '\\' */ - case 0x28: /* '(' */ - case 0x29: /* ')' */ - /* 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++) { - sp = *cpp; - /* - * terminate search on: - * root label - * compression pointer - * unusable offset - */ - while (*sp != 0 && (*sp & NS_CMPRSFLGS) == 0 && - (sp - msg) < 0x4000) { - dn = domain; - cp = sp; - while ((n = *cp++) != 0) { - /* - * check for indirection - */ - switch (n & NS_CMPRSFLGS) { - case 0: /* normal case, n == len */ - n = labellen(cp - 1); /* XXX */ - - 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: ; - sp += *sp + 1; - } - } - errno = ENOENT; - return (-1); -} - -static int -decode_bitstring(const char **cpp, char *dn, const char *eom) -{ - const char *cp = *cpp; - char *beg = dn, tc; - int b, blen, plen, i; - - if ((blen = (*cp & 0xff)) == 0) - blen = 256; - plen = (blen + 3) / 4; - plen += sizeof("\\[x/]") + (blen > 99 ? 3 : (blen > 9) ? 2 : 1); - if (dn + plen >= eom) - return(-1); - - cp++; - i = SPRINTF((dn, "\\[x")); - if (i < 0) - return (-1); - dn += i; - for (b = blen; b > 7; b -= 8, cp++) { - i = SPRINTF((dn, "%02x", *cp & 0xff)); - if (i < 0) - return (-1); - dn += i; - } - if (b > 4) { - tc = *cp++; - i = SPRINTF((dn, "%02x", tc & (0xff << (8 - b)))); - if (i < 0) - return (-1); - dn += i; - } else if (b > 0) { - tc = *cp++; - i = SPRINTF((dn, "%1x", - ((tc >> 4) & 0x0f) & (0x0f << (4 - b)))); - if (i < 0) - return (-1); - dn += i; - } - i = SPRINTF((dn, "/%d]", blen)); - if (i < 0) - return (-1); - dn += i; - - *cpp = cp; - return(dn - beg); -} - -static int -encode_bitsring(const char **bp, const char *end, char **labelp, - char ** dst, const char *eom) -{ - int afterslash = 0; - const char *cp = *bp; - char *tp, c; - const char *beg_blen; - char *end_blen = NULL; - int value = 0, count = 0, tbcount = 0, blen = 0; - - beg_blen = end_blen = NULL; - - /* a bitstring must contain at least 2 characters */ - if (end - cp < 2) - return(EINVAL); - - /* XXX: currently, only hex strings are supported */ - if (*cp++ != 'x') - return(EINVAL); - if (!isxdigit((*cp) & 0xff)) /* reject '\[x/BLEN]' */ - return(EINVAL); - - for (tp = *dst + 1; cp < end && tp < eom; cp++) { - switch((c = *cp)) { - case ']': /* end of the bitstring */ - if (afterslash) { - if (beg_blen == NULL) - return(EINVAL); - blen = (int)strtol(beg_blen, &end_blen, 10); - if (*end_blen != ']') - return(EINVAL); - } - if (count) - *tp++ = ((value << 4) & 0xff); - cp++; /* skip ']' */ - goto done; - case '/': - afterslash = 1; - break; - default: - if (afterslash) { - if (!isdigit(c&0xff)) - return(EINVAL); - if (beg_blen == NULL) { - - if (c == '0') { - /* blen never begings with 0 */ - return(EINVAL); - } - beg_blen = cp; - } - } else { - if (!isxdigit(c&0xff)) - return(EINVAL); - value <<= 4; - value += digitvalue[(int)c]; - count += 4; - tbcount += 4; - if (tbcount > 256) - return(EINVAL); - if (count == 8) { - *tp++ = value; - count = 0; - } - } - break; - } - } - done: - if (cp >= end || tp >= eom) - return(EMSGSIZE); - - /* - * bit length validation: - * If a <length> is present, the number of digits in the <bit-data> - * MUST be just sufficient to contain the number of bits specified - * by the <length>. If there are insignificant bits in a final - * hexadecimal or octal digit, they MUST be zero. - * RFC 2673, Section 3.2. - */ - if (blen > 0) { - int traillen; - - if (((blen + 3) & ~3) != tbcount) - return(EINVAL); - traillen = tbcount - blen; /* between 0 and 3 */ - if (((value << (8 - traillen)) & 0xff) != 0) - return(EINVAL); - } - else - blen = tbcount; - if (blen == 256) - blen = 0; - - /* encode the type and the significant bit fields */ - **labelp = DNS_LABELTYPE_BITSTRING; - **dst = blen; - - *bp = cp; - *dst = tp; - - return(0); -} - -static int -labellen(const u_char *lp) -{ - int bitlen; - u_char l = *lp; - - if ((l & NS_CMPRSFLGS) == NS_CMPRSFLGS) { - /* should be avoided by the caller */ - return(-1); - } - - if ((l & NS_CMPRSFLGS) == NS_TYPE_ELT) { - if (l == DNS_LABELTYPE_BITSTRING) { - if ((bitlen = *(lp + 1)) == 0) - bitlen = 256; - return((bitlen + 7 ) / 8 + 1); - } - return(-1); /* unknwon ELT */ - } - return(l); -} |
