diff options
Diffstat (limited to 'ares_parse_txt_reply.c')
| -rw-r--r-- | ares_parse_txt_reply.c | 53 |
1 files changed, 34 insertions, 19 deletions
diff --git a/ares_parse_txt_reply.c b/ares_parse_txt_reply.c index c99ee72..6950912 100644 --- a/ares_parse_txt_reply.c +++ b/ares_parse_txt_reply.c @@ -1,4 +1,7 @@ +/* $Id$ */ + /* Copyright (C) 2009 Jakub Hrozek <jhrozek@redhat.com> +* Copyright (C) 2009 Yang Tse <yangsita@gmail.com> * * Permission to use, copy, modify, and distribute this * software and its documentation for any purpose and without @@ -38,18 +41,21 @@ int ares_parse_txt_reply (const unsigned char *abuf, int alen, struct ares_txt_reply **txt_out, int *ntxtreply) { - unsigned char substr_len = 0; - unsigned char str_len = 0; - unsigned int qdcount, ancount; + size_t substr_len, str_len; + unsigned int qdcount, ancount, i; const unsigned char *aptr; const unsigned char *strptr; - int status, i, rr_type, rr_class, rr_len; + int status, rr_type, rr_class, rr_len; long len; char *hostname = NULL, *rr_name = NULL; struct ares_txt_reply *txt = NULL; + /* Set *txt_out to NULL for all failure cases. */ *txt_out = NULL; + /* Same with *nsrvreply. */ + *ntxtreply = 0; + /* Give up if abuf doesn't have room for a header. */ if (alen < HFIXEDSZ) return ARES_EBADRESP; @@ -82,11 +88,16 @@ ares_parse_txt_reply (const unsigned char *abuf, int alen, free (hostname); return ARES_ENOMEM; } - /* Zero out so we can safely free txt.txt even if NULL */ - memset(txt, 0, ancount * sizeof (struct ares_txt_reply)); + + /* Initialize ares_txt_reply array */ + for (i = 0; i < ancount; i++) + { + txt[i].txt = NULL; + txt[i].length = 0; + } /* Examine each answer resource record (RR) in turn. */ - for (i = 0; i < (int) ancount; i++) + for (i = 0; i < ancount; i++) { /* Decode the RR up to the data field. */ status = ares_expand_name (aptr, abuf, alen, &rr_name, &len); @@ -116,18 +127,17 @@ ares_parse_txt_reply (const unsigned char *abuf, int alen, * substrings contained therein. */ - /* Realloc would be expensive, compute the total length */ - txt[i].length = 0; + /* Compute total length to allow a single memory allocation */ strptr = aptr; while (strptr < (aptr + rr_len)) { - memcpy ((void *) &substr_len, strptr, sizeof (unsigned char)); + substr_len = (unsigned char)*strptr; txt[i].length += substr_len; strptr += substr_len + 1; } /* Including null byte */ - txt[i].txt = malloc (sizeof (unsigned char) * (txt[i].length + 1)); + txt[i].txt = malloc (txt[i].length + 1); if (txt[i].txt == NULL) { status = ARES_ENOMEM; @@ -135,15 +145,13 @@ ares_parse_txt_reply (const unsigned char *abuf, int alen, } /* Step through the list of substrings, concatenating them */ - substr_len = 0; str_len = 0; strptr = aptr; while (strptr < (aptr + rr_len)) { - memcpy ((void *) &substr_len, strptr, sizeof (unsigned char)); + substr_len = (unsigned char)*strptr; strptr++; - memcpy ((void *) txt[i].txt + str_len, strptr, - sizeof (unsigned char) * substr_len); + memcpy ((char *) txt[i].txt + str_len, strptr, substr_len); str_len += substr_len; strptr += substr_len; } @@ -159,18 +167,25 @@ ares_parse_txt_reply (const unsigned char *abuf, int alen, rr_name = NULL; } - free (hostname); - free (rr_name); + if (hostname); + free (hostname); + if (rr_name); + free (rr_name); /* clean up on error */ if (status != ARES_SUCCESS) { - ares_free_txt_reply(txt, ancount); + for (i = 0; i < ancount; i++) + { + if (txt[i].txt) + free (txt[i].txt); + } return status; } /* everything looks fine, return the data */ *txt_out = txt; *ntxtreply = ancount; - return 0; + + return ARES_SUCCESS; } |