1 |
diff -up openssl-fips-0.9.8e/ssl/s3_srvr.c.sgc-dos openssl-fips-0.9.8e/ssl/s3_srvr.c |
2 |
--- openssl-fips-0.9.8e/ssl/s3_srvr.c.sgc-dos 2012-03-19 17:42:34.490429863 +0100 |
3 |
+++ openssl-fips-0.9.8e/ssl/s3_srvr.c 2012-03-19 17:44:42.928114348 +0100 |
4 |
@@ -236,6 +236,7 @@ int ssl3_accept(SSL *s) |
5 |
} |
6 |
|
7 |
s->init_num=0; |
8 |
+ s->s3->flags &= ~SSL3_FLAGS_SGC_RESTART_DONE; |
9 |
|
10 |
if (s->state != SSL_ST_RENEGOTIATE) |
11 |
{ |
12 |
@@ -655,6 +656,13 @@ int ssl3_check_client_hello(SSL *s) |
13 |
s->s3->tmp.reuse_message = 1; |
14 |
if (s->s3->tmp.message_type == SSL3_MT_CLIENT_HELLO) |
15 |
{ |
16 |
+ /* We only allow the client to restart the handshake once per |
17 |
+ * negotiation. */ |
18 |
+ if (s->s3->flags & SSL3_FLAGS_SGC_RESTART_DONE) |
19 |
+ { |
20 |
+ SSLerr(SSL_F_SSL3_CHECK_CLIENT_HELLO, SSL_R_MULTIPLE_SGC_RESTARTS); |
21 |
+ return -1; |
22 |
+ } |
23 |
/* Throw away what we have done so far in the current handshake, |
24 |
* which will now be aborted. (A full SSL_clear would be too much.) |
25 |
* I hope that tmp.dh is the only thing that may need to be cleared |
26 |
@@ -666,6 +674,7 @@ int ssl3_check_client_hello(SSL *s) |
27 |
s->s3->tmp.dh = NULL; |
28 |
} |
29 |
#endif |
30 |
+ s->s3->flags |= SSL3_FLAGS_SGC_RESTART_DONE; |
31 |
return 2; |
32 |
} |
33 |
return 1; |
34 |
diff -up openssl-fips-0.9.8e/ssl/ssl3.h.sgc-dos openssl-fips-0.9.8e/ssl/ssl3.h |
35 |
--- openssl-fips-0.9.8e/ssl/ssl3.h.sgc-dos 2012-03-19 17:42:34.465429341 +0100 |
36 |
+++ openssl-fips-0.9.8e/ssl/ssl3.h 2012-03-19 17:42:34.532430741 +0100 |
37 |
@@ -333,6 +333,17 @@ typedef struct ssl3_buffer_st |
38 |
#define SSL3_FLAGS_DELAY_CLIENT_FINISHED 0x0002 |
39 |
#define SSL3_FLAGS_POP_BUFFER 0x0004 |
40 |
#define TLS1_FLAGS_TLS_PADDING_BUG 0x0008 |
41 |
+ |
42 |
+/* SSL3_FLAGS_SGC_RESTART_DONE is set when we |
43 |
+ * restart a handshake because of MS SGC and so prevents us |
44 |
+ * from restarting the handshake in a loop. It's reset on a |
45 |
+ * renegotiation, so effectively limits the client to one restart |
46 |
+ * per negotiation. This limits the possibility of a DDoS |
47 |
+ * attack where the client handshakes in a loop using SGC to |
48 |
+ * restart. Servers which permit renegotiation can still be |
49 |
+ * effected, but we can't prevent that. |
50 |
+ */ |
51 |
+#define SSL3_FLAGS_SGC_RESTART_DONE 0x0040 |
52 |
|
53 |
typedef struct ssl3_state_st |
54 |
{ |
55 |
diff -up openssl-fips-0.9.8e/ssl/ssl_err.c.sgc-dos openssl-fips-0.9.8e/ssl/ssl_err.c |
56 |
--- openssl-fips-0.9.8e/ssl/ssl_err.c.sgc-dos 2012-03-19 17:42:34.462429280 +0100 |
57 |
+++ openssl-fips-0.9.8e/ssl/ssl_err.c 2012-03-19 17:42:34.532430741 +0100 |
58 |
@@ -134,6 +134,7 @@ static ERR_STRING_DATA SSL_str_functs[]= |
59 |
{ERR_FUNC(SSL_F_SSL3_CALLBACK_CTRL), "SSL3_CALLBACK_CTRL"}, |
60 |
{ERR_FUNC(SSL_F_SSL3_CHANGE_CIPHER_STATE), "SSL3_CHANGE_CIPHER_STATE"}, |
61 |
{ERR_FUNC(SSL_F_SSL3_CHECK_CERT_AND_ALGORITHM), "SSL3_CHECK_CERT_AND_ALGORITHM"}, |
62 |
+{ERR_FUNC(SSL_F_SSL3_CHECK_CLIENT_HELLO), "SSL3_CHECK_CLIENT_HELLO"}, |
63 |
{ERR_FUNC(SSL_F_SSL3_CLIENT_HELLO), "SSL3_CLIENT_HELLO"}, |
64 |
{ERR_FUNC(SSL_F_SSL3_CONNECT), "SSL3_CONNECT"}, |
65 |
{ERR_FUNC(SSL_F_SSL3_CTRL), "SSL3_CTRL"}, |
66 |
@@ -361,6 +362,7 @@ static ERR_STRING_DATA SSL_str_reasons[] |
67 |
{ERR_REASON(SSL_R_MISSING_TMP_RSA_KEY) ,"missing tmp rsa key"}, |
68 |
{ERR_REASON(SSL_R_MISSING_TMP_RSA_PKEY) ,"missing tmp rsa pkey"}, |
69 |
{ERR_REASON(SSL_R_MISSING_VERIFY_MESSAGE),"missing verify message"}, |
70 |
+{ERR_REASON(SSL_R_MULTIPLE_SGC_RESTARTS) ,"multiple sgc restarts"}, |
71 |
{ERR_REASON(SSL_R_NON_SSLV2_INITIAL_PACKET),"non sslv2 initial packet"}, |
72 |
{ERR_REASON(SSL_R_NO_CERTIFICATES_RETURNED),"no certificates returned"}, |
73 |
{ERR_REASON(SSL_R_NO_CERTIFICATE_ASSIGNED),"no certificate assigned"}, |
74 |
diff -up openssl-fips-0.9.8e/ssl/ssl.h.sgc-dos openssl-fips-0.9.8e/ssl/ssl.h |
75 |
--- openssl-fips-0.9.8e/ssl/ssl.h.sgc-dos 2012-03-19 17:42:34.488429820 +0100 |
76 |
+++ openssl-fips-0.9.8e/ssl/ssl.h 2012-03-19 17:42:34.533430762 +0100 |
77 |
@@ -1634,6 +1634,7 @@ void ERR_load_SSL_strings(void); |
78 |
#define SSL_F_SSL3_CALLBACK_CTRL 233 |
79 |
#define SSL_F_SSL3_CHANGE_CIPHER_STATE 129 |
80 |
#define SSL_F_SSL3_CHECK_CERT_AND_ALGORITHM 130 |
81 |
+#define SSL_F_SSL3_CHECK_CLIENT_HELLO 293 |
82 |
#define SSL_F_SSL3_CLIENT_HELLO 131 |
83 |
#define SSL_F_SSL3_CONNECT 132 |
84 |
#define SSL_F_SSL3_CTRL 213 |
85 |
@@ -1858,6 +1859,7 @@ void ERR_load_SSL_strings(void); |
86 |
#define SSL_R_MISSING_TMP_RSA_KEY 172 |
87 |
#define SSL_R_MISSING_TMP_RSA_PKEY 173 |
88 |
#define SSL_R_MISSING_VERIFY_MESSAGE 174 |
89 |
+#define SSL_R_MULTIPLE_SGC_RESTARTS 325 |
90 |
#define SSL_R_NON_SSLV2_INITIAL_PACKET 175 |
91 |
#define SSL_R_NO_CERTIFICATES_RETURNED 176 |
92 |
#define SSL_R_NO_CERTIFICATE_ASSIGNED 177 |