return 1; /* we have all the prompts */
}
+static int
+_mech_plus_p(const char *mech, size_t len)
+{
+ return (len > 5 && strncasecmp(&mech[len - 5], "-PLUS", 5) == 0);
+}
+
+/*
+ * Order PLUS mechanisms first. Returns NUL separated list of
+ * *count items.
+ */
+static int
+_sasl_client_order_mechs(const sasl_utils_t *utils,
+ const char *mechs,
+ int has_cb_data,
+ char **ordered_mechs,
+ size_t *count,
+ int *server_can_cb)
+{
+ char *list, *listp;
+ size_t i, mechslen, start;
+
+ *count = 0;
+ *server_can_cb = 0;
+
+ if (mechs == NULL || mechs[0] == '\0')
+ return SASL_NOMECH;
+
+ mechslen = strlen(mechs);
+
+ listp = list = utils->malloc(mechslen + 1);
+ if (list == NULL)
+ return SASL_NOMEM;
+
+ /* xxx confirm this with rfc 2222
+ * SASL mechanism allowable characters are "AZaz-_"
+ * seperators can be any other characters and of any length
+ * even variable lengths between
+ *
+ * Apps should be encouraged to simply use space or comma space
+ * though
+ */
+#define ismechchar(c) (isalnum((c)) || (c) == '_' || (c) == '-')
+ do {
+ for (i = start = 0; i <= mechslen; i++) {
+ if (!ismechchar(mechs[i])) {
+ const char *mechp = &mechs[start];
+ size_t len = i - start;
+
+ if (len != 0 &&
+ _mech_plus_p(mechp, len) == has_cb_data) {
+ memcpy(listp, mechp, len);
+ listp[len] = '\0';
+ listp += len + 1;
+ (*count)++;
+ if (*server_can_cb == 0 && has_cb_data)
+ *server_can_cb = 1;
+ }
+ start = ++i;
+ }
+ }
+ if (has_cb_data)
+ has_cb_data = 0;
+ else
+ break;
+ } while (1);
+
+ if (*count == 0) {
+ utils->free(list);
+ return SASL_NOMECH;
+ }
+
+ *ordered_mechs = list;
+
+ return SASL_OK;
+}
+
+static inline int
+_sasl_cbinding_disp(sasl_client_params_t *cparams,
+ int mech_nego,
+ int server_can_cb,
+ unsigned int *cbindingdisp)
+{
+ /*
+ * If negotiating mechanisms, then we fail immediately if the
+ * client requires channel binding and the server does not
+ * advertise support. Otherwise we send "y" (which later will
+ * become "p" if we select a supporting mechanism).
+ *
+ * If the client explicitly selected a mechanism, then we only
+ * send channel bindings if they're marked critical.
+ */
+
+ *cbindingdisp = SASL_CB_DISP_NONE;
+
+ if (SASL_CB_PRESENT(cparams)) {
+ if (mech_nego) {
+ if (!server_can_cb && SASL_CB_CRITICAL(cparams))
+ return SASL_NOMECH;
+ else
+ *cbindingdisp = SASL_CB_DISP_WANT;
+ } else if (SASL_CB_CRITICAL(cparams)) {
+ *cbindingdisp = SASL_CB_DISP_USED;
+ }
+ }
+
+ return SASL_OK;
+}
+
/* select a mechanism for a connection
* mechlist -- mechanisms server has available (punctuation ignored)
* secret -- optional secret from previous session
* SASL_INTERACT -- user interaction needed to fill in prompt_need list
*/
-/* xxx confirm this with rfc 2222
- * SASL mechanism allowable characters are "AZaz-_"
- * seperators can be any other characters and of any length
- * even variable lengths between
- *
- * Apps should be encouraged to simply use space or comma space
- * though
- */
int sasl_client_start(sasl_conn_t *conn,
const char *mechlist,
sasl_interact_t **prompt_need,
const char **mech)
{
sasl_client_conn_t *c_conn= (sasl_client_conn_t *) conn;
- char name[SASL_MECHNAMEMAX + 1];
+ char *ordered_mechs = NULL, *name;
cmechanism_t *m=NULL,*bestm=NULL;
- size_t pos=0,place;
- size_t list_len;
+ size_t i, list_len;
sasl_ssf_t bestssf = 0, minssf = 0;
- int result;
+ int result, server_can_cb = 0;
+ unsigned int cbindingdisp;
if(_sasl_client_active==0) return SASL_NOTINIT;
minssf = conn->props.min_ssf - conn->external.ssf;
}
- c_conn->cparams->chanbindingflag = SASL_CB_FLAG_NONE;
-
- /* parse mechlist */
- list_len = strlen(mechlist);
-
- while (pos<list_len)
- {
- place=0;
- while ((pos<list_len) && (isalnum((unsigned char)mechlist[pos])
- || mechlist[pos] == '_'
- || mechlist[pos] == '-')) {
- name[place]=mechlist[pos];
- pos++;
- place++;
- if (SASL_MECHNAMEMAX < place) {
- place--;
- while(pos<list_len && (isalnum((unsigned char)mechlist[pos])
- || mechlist[pos] == '_'
- || mechlist[pos] == '-'))
- pos++;
- }
- }
- pos++;
- name[place]=0;
+ /* Order mechanisms so -PLUS are preferred */
+ result = _sasl_client_order_mechs(c_conn->cparams->utils,
+ mechlist,
+ SASL_CB_PRESENT(c_conn->cparams),
+ &ordered_mechs,
+ &list_len,
+ &server_can_cb);
+ if (result != 0)
+ goto done;
- if (! place) continue;
+ /*
+ * Determine channel binding disposition based on whether we
+ * are doing mechanism negotiation and whether server supports
+ * channel bindings.
+ */
+ result = _sasl_cbinding_disp(c_conn->cparams, (list_len > 1),
+ server_can_cb, &cbindingdisp);
+ if (result != 0)
+ goto done;
+ for (i = 0, name = ordered_mechs; i < list_len; i++) {
/* foreach in client list */
for (m = cmechlist->mech_list; m != NULL; m = m->next) {
int myflags, plus;
- if (!_sasl_is_equal_mech(name, m->m.plug->mech_name, &plus))
- continue;
+ if (!_sasl_is_equal_mech(name, m->m.plug->mech_name, &plus))
+ continue;
/* Do we have the prompts for it? */
if (!have_prompts(conn, m->m.plug))
}
/* Can we meet it's features? */
+ if (SASL_CB_PRESENT(c_conn->cparams) &&
+ !(m->m.plug->features & SASL_FEAT_CHANNEL_BINDING)) {
+ break;
+ }
+
if ((m->m.plug->features & SASL_FEAT_NEEDSERVERFQDN)
&& !conn->serverFQDN) {
break;
break;
}
- if (SASL_CB_PRESENT(c_conn->cparams)) {
- if (plus)
- c_conn->cparams->chanbindingflag = SASL_CB_FLAG_USED;
- else
- c_conn->cparams->chanbindingflag = SASL_CB_FLAG_WANT;
- }
+ if (SASL_CB_PRESENT(c_conn->cparams) && plus) {
+ cbindingdisp = SASL_CB_DISP_USED;
+ }
if (mech) {
*mech = m->m.plug->mech_name;
bestm = m;
break;
}
+ name += strlen(name) + 1;
}
if (bestm == NULL) {
c_conn->cparams->external_ssf = conn->external.ssf;
c_conn->cparams->props = conn->props;
+ c_conn->cparams->cbindingdisp = cbindingdisp;
c_conn->mech = bestm;
/* init that plugin */
result = SASL_CONTINUE;
done:
+ if (ordered_mechs != NULL)
+ c_conn->cparams->utils->free(ordered_mechs);
RETURN(conn, result);
}
projects / cyrus-sasl.git / blobdiff