1 2 /* Copyright 1998 by the Massachusetts Institute of Technology. 3 * 4 * Permission to use, copy, modify, and distribute this 5 * software and its documentation for any purpose and without 6 * fee is hereby granted, provided that the above copyright 7 * notice appear in all copies and that both that copyright 8 * notice and this permission notice appear in supporting 9 * documentation, and that the name of M.I.T. not be used in 10 * advertising or publicity pertaining to distribution of the 11 * software without specific, written prior permission. 12 * M.I.T. makes no representations about the suitability of 13 * this software for any purpose. It is provided "as is" 14 * without express or implied warranty. 15 */ 16 17 #include "ares_setup.h" 18 19 #ifdef HAVE_SYS_SOCKET_H 20 # include <sys/socket.h> 21 #endif 22 #ifdef HAVE_NETINET_IN_H 23 # include <netinet/in.h> 24 #endif 25 #ifdef HAVE_ARPA_NAMESER_H 26 # include <arpa/nameser.h> 27 #else 28 # include "nameser.h" 29 #endif 30 31 #include <string.h> 32 #include <stdlib.h> 33 #include "ares.h" 34 #include "ares_private.h" /* for the memdebug */ 35 36 /* Simply decodes a length-encoded character string. The first byte of the 37 * input is the length of the string to be returned and the bytes thereafter 38 * are the characters of the string. The returned result will be NULL 39 * terminated. 40 */ 41 int ares_expand_string(const unsigned char *encoded, 42 const unsigned char *abuf, 43 int alen, 44 unsigned char **s, 45 long *enclen) 46 { 47 unsigned char *q; 48 union { 49 ssize_t sig; 50 size_t uns; 51 } elen; 52 53 if (encoded == abuf+alen) 54 return ARES_EBADSTR; 55 56 elen.uns = *encoded; 57 if (encoded+elen.sig+1 > abuf+alen) 58 return ARES_EBADSTR; 59 60 encoded++; 61 62 *s = malloc(elen.uns+1); 63 if (*s == NULL) 64 return ARES_ENOMEM; 65 q = *s; 66 strncpy((char *)q, (char *)encoded, elen.uns); 67 q[elen.uns] = '\0'; 68 69 *s = q; 70 71 *enclen = (long)(elen.sig+1); 72 73 return ARES_SUCCESS; 74 } 75 76
