1 /*
2  * cb.c
3  *
4  * Version:     $Id: 372b8fa82286475cea9e79857aadfafc1e741d63 $
5  *
6  *   This program is free software; you can redistribute it and/or modify
7  *   it under the terms of the GNU General Public License as published by
8  *   the Free Software Foundation; either version 2 of the License, or
9  *   (at your option) any later version.
10  *
11  *   This program is distributed in the hope that it will be useful,
12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *   GNU General Public License for more details.
15  *
16  *   You should have received a copy of the GNU General Public License
17  *   along with this program; if not, write to the Free Software
18  *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
19  *
20  * Copyright 2001  hereUare Communications, Inc. <raghud@hereuare.com>
21  * Copyright 2006  The FreeRADIUS server project
22  */
23 
24 RCSID("$Id: 372b8fa82286475cea9e79857aadfafc1e741d63 $")
25 USES_APPLE_DEPRECATED_API	/* OpenSSL API has been deprecated by Apple */
26 
27 #include <freeradius-devel/radiusd.h>
28 
29 #ifdef WITH_TLS
cbtls_info(SSL const * s,int where,int ret)30 void cbtls_info(SSL const *s, int where, int ret)
31 {
32 	char const *role, *state;
33 	REQUEST *request = SSL_get_ex_data(s, FR_TLS_EX_INDEX_REQUEST);
34 
35 	if ((where & ~SSL_ST_MASK) & SSL_ST_CONNECT) {
36 		role = "Client ";
37 	} else if (((where & ~SSL_ST_MASK)) & SSL_ST_ACCEPT) {
38 		role = "Server ";
39 	} else {
40 		role = "";
41 	}
42 
43 	state = SSL_state_string_long(s);
44 	state = state ? state : "<none>";
45 
46 	if ((where & SSL_CB_LOOP) || (where & SSL_CB_HANDSHAKE_START) || (where & SSL_CB_HANDSHAKE_DONE)) {
47 		if (RDEBUG_ENABLED3) {
48 			char const *abbrv = SSL_state_string(s);
49 			size_t len;
50 #if OPENSSL_VERSION_NUMBER >= 0x10100000L
51 			STACK_OF(SSL_CIPHER) *client_ciphers;
52 			STACK_OF(SSL_CIPHER) *server_ciphers;
53 #endif
54 
55 			/*
56 			 *	Trim crappy OpenSSL state strings...
57 			 */
58 			len = strlen(abbrv);
59 			if ((len > 1) && (abbrv[len - 1] == ' ')) len--;
60 
61 			RDEBUG3("(TLS) Handshake state [%.*s] - %s%s (%d)",
62 				(int)len, abbrv, role, state, SSL_get_state(s));
63 
64 			/*
65 			 *	After a ClientHello, list all the proposed ciphers from the client
66 			 */
67 #if OPENSSL_VERSION_NUMBER >= 0x10100000L
68 			if (SSL_get_state(s) == TLS_ST_SR_CLNT_HELLO) {
69 				int i;
70 				int num_ciphers;
71 				const SSL_CIPHER *this_cipher;
72 
73 				server_ciphers = SSL_get_ciphers(s);
74 				if (server_ciphers) {
75 					RDEBUG3("Server preferred ciphers (by priority)");
76 					num_ciphers = sk_SSL_CIPHER_num(server_ciphers);
77 					for (i = 0; i < num_ciphers; i++) {
78 						this_cipher = sk_SSL_CIPHER_value(server_ciphers, i);
79 						RDEBUG3("(TLS)    [%i] %s", i, SSL_CIPHER_get_name(this_cipher));
80 					}
81 				}
82 
83 				client_ciphers = SSL_get_client_ciphers(s);
84 				if (client_ciphers) {
85 					RDEBUG3("Client preferred ciphers (by priority)");
86 					num_ciphers = sk_SSL_CIPHER_num(client_ciphers);
87 					for (i = 0; i < num_ciphers; i++) {
88 						this_cipher = sk_SSL_CIPHER_value(client_ciphers, i);
89 						RDEBUG3("(TLS)    [%i] %s", i, SSL_CIPHER_get_name(this_cipher));
90 					}
91 				}
92 			}
93 #endif
94 		} else {
95 			RDEBUG2("(TLS) Handshake state - %s%s", role, state);
96 		}
97 		return;
98 	}
99 
100 	if (where & SSL_CB_ALERT) {
101 		if ((ret & 0xff) == SSL_AD_CLOSE_NOTIFY) return;
102 
103 		RERROR("(TLS) Alert %s:%s:%s", (where & SSL_CB_READ) ? "read": "write",
104 		       SSL_alert_type_string_long(ret), SSL_alert_desc_string_long(ret));
105 		return;
106 	}
107 
108 	if (where & SSL_CB_EXIT) {
109 		if (ret == 0) {
110 			RERROR("(TLS) %s: Failed in %s", role, state);
111 			return;
112 		}
113 
114 		if (ret < 0) {
115 			if (SSL_want_read(s)) {
116 				RDEBUG2("(TLS) %s: Need to read more data: %s", role, state);
117 				return;
118 			}
119 			RERROR("(TLS) %s: Error in %s", role, state);
120 		}
121 	}
122 }
123 
124 /*
125  *	Fill in our 'info' with TLS data.
126  */
cbtls_msg(int write_p,int msg_version,int content_type,void const * inbuf,size_t len,SSL * ssl UNUSED,void * arg)127 void cbtls_msg(int write_p, int msg_version, int content_type,
128 	       void const *inbuf, size_t len,
129 	       SSL *ssl UNUSED, void *arg)
130 {
131 	uint8_t const *buf = inbuf;
132 	tls_session_t *state = (tls_session_t *)arg;
133 
134 	/*
135 	 *	OpenSSL 1.0.2 calls this function with 'pseudo'
136 	 *	content types.  Which breaks our tracking of
137 	 *	the SSL Session state.
138 	 */
139 	if ((msg_version == 0) && (content_type > UINT8_MAX)) {
140 		DEBUG4("(TLS) Ignoring cbtls_msg call with pseudo content type %i, version %i",
141 		       content_type, msg_version);
142 		return;
143 	}
144 
145 	if ((write_p != 0) && (write_p != 1)) {
146 		DEBUG4("(TLS) Ignoring cbtls_msg call with invalid write_p %d", write_p);
147 		return;
148 	}
149 
150 	/*
151 	 *	Work around bug #298, where we may be called with a NULL
152 	 *	argument.  We should really log a serious error
153 	 */
154 	if (!state) return;
155 
156 	if (rad_debug_lvl > 3) {
157 		size_t i, j, data_len = len;
158 		char buffer[3*16 + 1];
159 		uint8_t const *in = inbuf;
160 
161 		DEBUG("(TLS) Received %zu bytes of TLS data", len);
162 		if (data_len > 256) data_len = 256;
163 
164 		for (i = 0; i < data_len; i += 16) {
165 			for (j = 0; j < 16; j++) {
166 				if ((i + j) >= data_len) break;
167 
168 				sprintf(buffer + 3 * j, "%02x ", in[i + j]);
169 			}
170 
171 			DEBUG("(TLS)        %s", buffer);
172 		}
173 	}
174 
175 	/*
176 	 *	0 - received (from peer)
177 	 *	1 - sending (to peer)
178 	 */
179 	state->info.origin = write_p;
180 	state->info.content_type = content_type;
181 	state->info.record_len = len;
182 	state->info.version = msg_version;
183 	state->info.initialized = true;
184 
185 	if (content_type == SSL3_RT_ALERT) {
186 		state->info.alert_level = buf[0];
187 		state->info.alert_description = buf[1];
188 		state->info.handshake_type = 0x00;
189 
190 	} else if (content_type == SSL3_RT_HANDSHAKE) {
191 		state->info.handshake_type = buf[0];
192 		state->info.alert_level = 0x00;
193 		state->info.alert_description = 0x00;
194 
195 #if OPENSSL_VERSION_NUMBER >= 0x10101000L
196 	} else if (content_type == SSL3_RT_INNER_CONTENT_TYPE && buf[0] == SSL3_RT_APPLICATION_DATA) {
197 		/* let tls_ack_handler set application_data */
198 		state->info.content_type = SSL3_RT_HANDSHAKE;
199 #endif
200 
201 #ifdef SSL3_RT_HEARTBEAT
202 	} else if (content_type == TLS1_RT_HEARTBEAT) {
203 		uint8_t *p = buf;
204 
205 		if ((len >= 3) && (p[0] == 1)) {
206 			size_t payload_len;
207 
208 			payload_len = (p[1] << 8) | p[2];
209 
210 			if ((payload_len + 3) > len) {
211 				state->invalid_hb_used = true;
212 				ERROR("OpenSSL Heartbeat attack detected.  Closing connection");
213 				return;
214 			}
215 		}
216 #endif
217 	}
218 
219 	tls_session_information(state);
220 }
221 
cbtls_password(char * buf,int num,int rwflag UNUSED,void * userdata)222 int cbtls_password(char *buf,
223 		   int num,
224 		   int rwflag UNUSED,
225 		   void *userdata)
226 {
227 	size_t len;
228 
229 	len = strlcpy(buf, (char *)userdata, num);
230 	if (len >= (size_t) num) {
231 		ERROR("Password too long.  Maximum length is %i bytes", num - 1);
232 		return 0;
233 	}
234 
235 	return len;
236 }
237 
238 #endif
239