--- /dev/null
+/*
+ * EAP common peer/server definitions
+ * Copyright (c) 2004-2007, Jouni Malinen <j@w1.fi>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Alternatively, this software may be distributed under the terms of BSD
+ * license.
+ *
+ * See README and COPYING for more details.
+ */
+
+#include "includes.h"
+
+#include "common.h"
+#include "eap_defs.h"
+#include "eap_common.h"
+
+/**
+ * eap_hdr_validate - Validate EAP header
+ * @vendor: Expected EAP Vendor-Id (0 = IETF)
+ * @eap_type: Expected EAP type number
+ * @msg: EAP frame (starting with EAP header)
+ * @plen: Pointer to variable to contain the returned payload length
+ * Returns: Pointer to EAP payload (after type field), or %NULL on failure
+ *
+ * This is a helper function for EAP method implementations. This is usually
+ * called in the beginning of struct eap_method::process() function to verify
+ * that the received EAP request packet has a valid header. This function is
+ * able to process both legacy and expanded EAP headers and in most cases, the
+ * caller can just use the returned payload pointer (into *plen) for processing
+ * the payload regardless of whether the packet used the expanded EAP header or
+ * not.
+ */
+const u8 * eap_hdr_validate(int vendor, EapType eap_type,
+ const struct wpabuf *msg, size_t *plen)
+{
+ const struct eap_hdr *hdr;
+ const u8 *pos;
+ size_t len;
+
+ hdr = wpabuf_head(msg);
+
+ if (wpabuf_len(msg) < sizeof(*hdr)) {
+ wpa_printf(MSG_INFO, "EAP: Too short EAP frame");
+ return NULL;
+ }
+
+ len = be_to_host16(hdr->length);
+ if (len < sizeof(*hdr) + 1 || len > wpabuf_len(msg)) {
+ wpa_printf(MSG_INFO, "EAP: Invalid EAP length");
+ return NULL;
+ }
+
+ pos = (const u8 *) (hdr + 1);
+
+ if (*pos == EAP_TYPE_EXPANDED) {
+ int exp_vendor;
+ u32 exp_type;
+ if (len < sizeof(*hdr) + 8) {
+ wpa_printf(MSG_INFO, "EAP: Invalid expanded EAP "
+ "length");
+ return NULL;
+ }
+ pos++;
+ exp_vendor = WPA_GET_BE24(pos);
+ pos += 3;
+ exp_type = WPA_GET_BE32(pos);
+ pos += 4;
+ if (exp_vendor != vendor || exp_type != (u32) eap_type) {
+ wpa_printf(MSG_INFO, "EAP: Invalid expanded frame "
+ "type");
+ return NULL;
+ }
+
+ *plen = len - sizeof(*hdr) - 8;
+ return pos;
+ } else {
+ if (vendor != EAP_VENDOR_IETF || *pos != eap_type) {
+ wpa_printf(MSG_INFO, "EAP: Invalid frame type");
+ return NULL;
+ }
+ *plen = len - sizeof(*hdr) - 1;
+ return pos + 1;
+ }
+}
+
+
+/**
+ * eap_msg_alloc - Allocate a buffer for an EAP message
+ * @vendor: Vendor-Id (0 = IETF)
+ * @type: EAP type
+ * @payload_len: Payload length in bytes (data after Type)
+ * @code: Message Code (EAP_CODE_*)
+ * @identifier: Identifier
+ * Returns: Pointer to the allocated message buffer or %NULL on error
+ *
+ * This function can be used to allocate a buffer for an EAP message and fill
+ * in the EAP header. This function is automatically using expanded EAP header
+ * if the selected Vendor-Id is not IETF. In other words, most EAP methods do
+ * not need to separately select which header type to use when using this
+ * function to allocate the message buffers. The returned buffer has room for
+ * payload_len bytes and has the EAP header and Type field already filled in.
+ */
+struct wpabuf * eap_msg_alloc(int vendor, EapType type, size_t payload_len,
+ u8 code, u8 identifier)
+{
+ struct wpabuf *buf;
+ struct eap_hdr *hdr;
+ size_t len;
+
+ len = sizeof(struct eap_hdr) + (vendor == EAP_VENDOR_IETF ? 1 : 8) +
+ payload_len;
+ buf = wpabuf_alloc(len);
+ if (buf == NULL)
+ return NULL;
+
+ hdr = wpabuf_put(buf, sizeof(*hdr));
+ hdr->code = code;
+ hdr->identifier = identifier;
+ hdr->length = host_to_be16(len);
+
+ if (vendor == EAP_VENDOR_IETF) {
+ wpabuf_put_u8(buf, type);
+ } else {
+ wpabuf_put_u8(buf, EAP_TYPE_EXPANDED);
+ wpabuf_put_be24(buf, vendor);
+ wpabuf_put_be32(buf, type);
+ }
+
+ return buf;
+}
+
+
+/**
+ * eap_update_len - Update EAP header length
+ * @msg: EAP message from eap_msg_alloc
+ *
+ * This function updates the length field in the EAP header to match with the
+ * current length for the buffer. This allows eap_msg_alloc() to be used to
+ * allocate a larger buffer than the exact message length (e.g., if exact
+ * message length is not yet known).
+ */
+void eap_update_len(struct wpabuf *msg)
+{
+ struct eap_hdr *hdr;
+ hdr = wpabuf_mhead(msg);
+ if (wpabuf_len(msg) < sizeof(*hdr))
+ return;
+ hdr->length = host_to_be16(wpabuf_len(msg));
+}
+
+
+/**
+ * eap_get_id - Get EAP Identifier from wpabuf
+ * @msg: Buffer starting with an EAP header
+ * Returns: The Identifier field from the EAP header
+ */
+u8 eap_get_id(const struct wpabuf *msg)
+{
+ const struct eap_hdr *eap;
+
+ if (wpabuf_len(msg) < sizeof(*eap))
+ return 0;
+
+ eap = wpabuf_head(msg);
+ return eap->identifier;
+}
+
+
+/**
+ * eap_get_id - Get EAP Type from wpabuf
+ * @msg: Buffer starting with an EAP header
+ * Returns: The EAP Type after the EAP header
+ */
+EapType eap_get_type(const struct wpabuf *msg)
+{
+ if (wpabuf_len(msg) < sizeof(struct eap_hdr) + 1)
+ return EAP_TYPE_NONE;
+
+ return ((const u8 *) wpabuf_head(msg))[sizeof(struct eap_hdr)];
+}
projects / mech_eap.orig / blobdiff