improve algorithm list parsing

This commit is contained in:
Matt Johnston 2016-07-11 22:40:38 +08:00
parent 64e6e3aca9
commit 4f5d0756c2

View File

@ -531,21 +531,6 @@ check_algo(const char* algo_name, algo_type *algos)
return NULL;
}
static void
try_add_algo(const char *algo_name, algo_type *algos,
const char *algo_desc, algo_type * new_algos, int *num_ret)
{
algo_type *match_algo = check_algo(algo_name, algos);
if (!match_algo)
{
dropbear_log(LOG_WARNING, "This Dropbear program does not support '%s' %s algorithm", algo_name, algo_desc);
return;
}
new_algos[*num_ret] = *match_algo;
(*num_ret)++;
}
/* Checks a user provided comma-separated algorithm list for available
* options. Any that are not acceptable are removed in-place. Returns the
* number of valid algorithms. */
@ -553,30 +538,43 @@ int
check_user_algos(const char* user_algo_list, algo_type * algos,
const char *algo_desc)
{
algo_type new_algos[MAX_PROPOSED_ALGO];
/* this has two passes. first we sweep through the given list of
* algorithms and mark them as usable=2 in the algo_type[] array... */
int num_ret = 0;
algo_type new_algos[MAX_PROPOSED_ALGO+1];
char *work_list = m_strdup(user_algo_list);
char *last_name = work_list;
char *start = work_list;
char *c;
for (c = work_list; *c; c++)
int n;
/* So we can iterate and look for null terminator */
memset(new_algos, 0x0, sizeof(new_algos));
for (c = work_list, n = 0; ; c++)
{
if (*c == ',')
{
char oc = *c;
if (n >= MAX_PROPOSED_ALGO) {
dropbear_exit("Too many algorithms '%s'", user_algo_list);
}
if (*c == ',' || *c == '\0') {
algo_type *match_algo = NULL;
*c = '\0';
try_add_algo(last_name, algos, algo_desc, new_algos, &num_ret);
match_algo = check_algo(start, algos);
if (match_algo) {
if (check_algo(start, new_algos)) {
TRACE(("Skip repeated algorithm '%s'", start))
} else {
new_algos[n] = *match_algo;
n++;
}
} else {
dropbear_log(LOG_WARNING, "This Dropbear program does not support '%s' %s algorithm", start, algo_desc);
}
c++;
last_name = c;
start = c;
}
if (oc == '\0') {
break;
}
}
try_add_algo(last_name, algos, algo_desc, new_algos, &num_ret);
m_free(work_list);
new_algos[num_ret].name = NULL;
/* Copy one more as a blank delimiter */
memcpy(algos, new_algos, sizeof(*new_algos) * (num_ret+1));
return num_ret;
/* n+1 to include a null terminator */
memcpy(algos, new_algos, sizeof(*new_algos) * (n+1));
return n;
}
#endif /* ENABLE_USER_ALGO_LIST */