Commit 94162d62 authored by Yang Tse's avatar Yang Tse
Browse files

Avoid a segfault when generating a DNS "Transaction ID" in internal 

function init_id_key() under low memory conditions.
parent 059707be

ares/CHANGES

+4 −0
Original line number Diff line number Diff line 
  Changelog for the c-ares project



* October 2 2007 (Daniel Stenberg)



- ares_strerror() segfaulted if the input error number was out of the currently

  supported range.



- Yang Tse: Avoid a segfault when generating a DNS "Transaction ID" in

  internal function init_id_key() under low memory conditions.



* September 28 2007 (Daniel Stenberg)



- Bumped version to 1.5.0 for next release and soname bumped to 2 due to ABI

ares/ares_init.c

+18 −7
Original line number Diff line number Diff line
@@ -75,7 +75,7 @@ static int config_nameserver(struct server_state **servers, int *nservers, 
static int set_search(ares_channel channel, const char *str);

static int set_options(ares_channel channel, const char *str);

static const char *try_option(const char *p, const char *q, const char *opt);

static void init_id_key(rc4_key* key,int key_data_len);

static int init_id_key(rc4_key* key,int key_data_len);



#ifndef WIN32

static int sortlist_alloc(struct apattern **sortlist, int *nsort, struct apattern *pat);
@@ -189,6 +189,18 @@ int ares_init_options(ares_channel *channelptr, struct ares_options *options, 
      DEBUGF(fprintf(stderr, "Error: init_by_defaults failed: %s\n",

                     ares_strerror(status)));

  }



  /* Generate random key */



  if (status == ARES_SUCCESS) {

    status = init_id_key(&channel->id_key, ARES_ID_KEY_LEN);

    if (status == ARES_SUCCESS)

      channel->next_id = ares__generate_new_id(&channel->id_key);

    else

      DEBUGF(fprintf(stderr, "Error: init_id_key failed: %s\n",

                     ares_strerror(status)));

  }



  if (status != ARES_SUCCESS)

    {

      /* Something failed; clean up memory we may have allocated. */
@@ -228,10 +240,6 @@ int ares_init_options(ares_channel *channelptr, struct ares_options *options, 
      server->is_broken = 0;

    }



  init_id_key(&channel->id_key, ARES_ID_KEY_LEN);



  channel->next_id = ares__generate_new_id(&channel->id_key);



  *channelptr = channel;

  return ARES_SUCCESS;

}
@@ -1345,7 +1353,7 @@ static void randomize_key(unsigned char* key,int key_data_len) 
  }

}



static void init_id_key(rc4_key* key,int key_data_len)

static int init_id_key(rc4_key* key,int key_data_len)

{

  unsigned char index1;

  unsigned char index2;
@@ -1354,6 +1362,9 @@ static void init_id_key(rc4_key* key,int key_data_len) 
  unsigned char *key_data_ptr = 0;



  key_data_ptr = calloc(1,key_data_len);

  if (!key_data_ptr)

    return ARES_ENOMEM;



  randomize_key(key->state,key_data_len);

  state = &key->state[0];

  for(counter = 0; counter < 256; counter++)
@@ -1372,7 +1383,7 @@ static void init_id_key(rc4_key* key,int key_data_len) 
    index1 = (index1 + 1) % key_data_len;

  }

  free(key_data_ptr);



  return ARES_SUCCESS;

}



short ares__generate_new_id(rc4_key* key)