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@@ -0,0 +1,66 @@
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+From e28a58be26184c2a23f80b410e0997ef1bd5d578 Mon Sep 17 00:00:00 2001
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+From: Jouni Malinen <[email protected]>
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+Date: Fri, 1 May 2015 16:40:44 +0300
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+Subject: [PATCH 2/5] EAP-pwd server: Fix payload length validation for Commit
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+ and Confirm
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+
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+The length of the received Commit and Confirm message payloads was not
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+checked before reading them. This could result in a buffer read
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+overflow when processing an invalid message.
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+
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+Fix this by verifying that the payload is of expected length before
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+processing it. In addition, enforce correct state transition sequence to
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+make sure there is no unexpected behavior if receiving a Commit/Confirm
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+message before the previous exchanges have been completed.
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+
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+Thanks to Kostya Kortchinsky of Google security team for discovering and
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+reporting this issue.
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+
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+Signed-off-by: Jouni Malinen <[email protected]>
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+---
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+ src/eap_server/eap_server_pwd.c | 19 +++++++++++++++++++
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+ 1 file changed, 19 insertions(+)
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+
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+diff --git a/src/eap_server/eap_server_pwd.c b/src/eap_server/eap_server_pwd.c
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+index 66bd5d2..3189105 100644
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+--- a/src/eap_server/eap_server_pwd.c
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++++ b/src/eap_server/eap_server_pwd.c
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+@@ -656,9 +656,21 @@ eap_pwd_process_commit_resp(struct eap_sm *sm, struct eap_pwd_data *data,
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+ BIGNUM *x = NULL, *y = NULL, *cofactor = NULL;
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+ EC_POINT *K = NULL, *point = NULL;
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+ int res = 0;
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++ size_t prime_len, order_len;
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+
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+ wpa_printf(MSG_DEBUG, "EAP-pwd: Received commit response");
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+
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++ prime_len = BN_num_bytes(data->grp->prime);
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++ order_len = BN_num_bytes(data->grp->order);
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++
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++ if (payload_len != 2 * prime_len + order_len) {
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++ wpa_printf(MSG_INFO,
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++ "EAP-pwd: Unexpected Commit payload length %u (expected %u)",
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++ (unsigned int) payload_len,
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++ (unsigned int) (2 * prime_len + order_len));
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++ goto fin;
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++ }
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++
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+ if (((data->peer_scalar = BN_new()) == NULL) ||
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+ ((data->k = BN_new()) == NULL) ||
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+ ((cofactor = BN_new()) == NULL) ||
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+@@ -774,6 +786,13 @@ eap_pwd_process_confirm_resp(struct eap_sm *sm, struct eap_pwd_data *data,
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+ u8 conf[SHA256_MAC_LEN], *cruft = NULL, *ptr;
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+ int offset;
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+
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++ if (payload_len != SHA256_MAC_LEN) {
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++ wpa_printf(MSG_INFO,
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++ "EAP-pwd: Unexpected Confirm payload length %u (expected %u)",
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++ (unsigned int) payload_len, SHA256_MAC_LEN);
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++ goto fin;
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++ }
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++
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+ /* build up the ciphersuite: group | random_function | prf */
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+ grp = htons(data->group_num);
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+ ptr = (u8 *) &cs;
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+--
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+1.9.1
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+
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