9 #include <openssl/ssl.h>
10 #include <openssl/err.h>
11 #include <openssl/rand.h>
14 #if TIME_WITH_SYS_TIME
15 # include <sys/time.h>
19 # include <sys/time.h>
29 #ifdef HAVE_SYS_SELECT_H
30 #include <sys/select.h>
35 #include "serv_crypto.h"
36 #include "sysdep_decls.h"
37 #include "serv_extensions.h"
41 SSL_CTX *ssl_ctx; /* SSL context */
42 pthread_mutex_t **SSLCritters; /* Things needing locking */
44 static unsigned long id_callback(void)
46 return (unsigned long) pthread_self();
50 * Set up the cert things on the server side. We do need both the
51 * private key (in key_file) and the cert (in cert_file).
52 * Both files may be identical.
54 * This function is taken from OpenSSL apps/s_cb.c
57 static int set_cert_stuff(SSL_CTX * ctx,
58 const char *cert_file, const char *key_file)
60 if (cert_file != NULL) {
61 if (SSL_CTX_use_certificate_file(ctx, cert_file,
62 SSL_FILETYPE_PEM) <= 0) {
63 lprintf(3, "unable to get certificate from '%s'",
69 if (SSL_CTX_use_PrivateKey_file(ctx, key_file,
70 SSL_FILETYPE_PEM) <= 0) {
71 lprintf(3, "unable to get private key from '%s'",
75 /* Now we know that a key and cert have been set against
77 if (!SSL_CTX_check_private_key(ctx)) {
79 "Private key does not match the certificate public key");
89 SSL_METHOD *ssl_method;
92 if (!access("/var/run/egd-pool", F_OK))
93 RAND_egd("/var/run/egd-pool");
97 "PRNG not adequately seeded, won't do SSL/TLS\n");
101 mallok(CRYPTO_num_locks() * sizeof(pthread_mutex_t *));
103 lprintf(1, "citserver: can't allocate memory!!\n");
104 /* Nothing's been initialized, just die */
109 for (a = 0; a < CRYPTO_num_locks(); a++) {
110 SSLCritters[a] = mallok(sizeof(pthread_mutex_t));
111 if (!SSLCritters[a]) {
113 "citserver: can't allocate memory!!\n");
114 /* Nothing's been initialized, just die */
117 pthread_mutex_init(SSLCritters[a], NULL);
122 * Initialize SSL transport layer
125 SSL_load_error_strings();
126 ssl_method = SSLv23_server_method();
127 if (!(ssl_ctx = SSL_CTX_new(ssl_method))) {
128 lprintf(2, "SSL_CTX_new failed: %s\n",
129 ERR_reason_error_string(ERR_get_error()));
132 if (!(SSL_CTX_set_cipher_list(ssl_ctx, CIT_CIPHERS))) {
133 lprintf(2, "SSL: No ciphers available\n");
134 SSL_CTX_free(ssl_ctx);
139 #if SSLEAY_VERSION_NUMBER >= 0x00906000L
140 SSL_CTX_set_mode(ssl_ctx, SSL_CTX_get_mode(ssl_ctx) |
141 SSL_MODE_AUTO_RETRY);
145 CRYPTO_set_locking_callback(ssl_lock);
146 CRYPTO_set_id_callback(id_callback);
148 /* Load DH parameters into the context */
151 lprintf(2, "init_ssl() can't allocate a DH object: %s\n",
152 ERR_reason_error_string(ERR_get_error()));
153 SSL_CTX_free(ssl_ctx);
157 if (!(BN_hex2bn(&(dh->p), DH_P))) {
158 lprintf(2, "init_ssl() can't assign DH_P: %s\n",
159 ERR_reason_error_string(ERR_get_error()));
160 SSL_CTX_free(ssl_ctx);
164 if (!(BN_hex2bn(&(dh->g), DH_G))) {
165 lprintf(2, "init_ssl() can't assign DH_G: %s\n",
166 ERR_reason_error_string(ERR_get_error()));
167 SSL_CTX_free(ssl_ctx);
172 SSL_CTX_set_tmp_dh(ssl_ctx, dh);
175 /* Get our certificates in order */
176 if (set_cert_stuff(ssl_ctx,
177 BBSDIR "/keys/citadel.cer",
178 BBSDIR "/keys/citadel.key") != 1) {
180 lprintf(3, "SSL ERROR: cert is bad!\n");
184 /* Finally let the server know we're here */
185 CtdlRegisterProtoHook(cmd_stls, "STLS", "Start SSL/TLS session");
186 CtdlRegisterProtoHook(cmd_gtls, "GTLS",
187 "Get SSL/TLS session status");
188 CtdlRegisterSessionHook(endtls, EVT_STOP);
193 * client_write_ssl() Send binary data to the client encrypted.
195 void client_write_ssl(char *buf, int nbytes)
203 while (nremain > 0) {
204 if (SSL_want_write(CC->ssl)) {
205 if ((SSL_read(CC->ssl, junk, 0)) < 1) {
206 lprintf(9, "SSL_read in client_write:\n");
207 ERR_print_errors_fp(stderr);
211 SSL_write(CC->ssl, &buf[nbytes - nremain], nremain);
215 errval = SSL_get_error(CC->ssl, retval);
216 if (errval == SSL_ERROR_WANT_READ ||
217 errval == SSL_ERROR_WANT_WRITE) {
221 lprintf(9, "SSL_write got error %ld, ret %d\n", errval, retval);
223 lprintf(9, "errno is %d\n", errno);
225 client_write(&buf[nbytes - nremain], nremain);
234 * client_read_ssl() - read data from the encrypted layer.
236 int client_read_ssl(char *buf, int bytes, int timeout)
248 while (len < bytes) {
251 * This code is disabled because we don't need it when
252 * using blocking reads (which we are). -IO
255 s = BIO_get_fd(CC->ssl->rbio, NULL);
260 retval = select(s + 1, &rfds, NULL, NULL, &tv);
262 if (FD_ISSET(s, &rfds) == 0) {
267 if (SSL_want_read(CC->ssl)) {
268 if ((SSL_write(CC->ssl, junk, 0)) < 1) {
269 lprintf(9, "SSL_write in client_read:\n");
270 ERR_print_errors_fp(stderr);
273 rlen = SSL_read(CC->ssl, &buf[len], bytes - len);
277 errval = SSL_get_error(CC->ssl, rlen);
278 if (errval == SSL_ERROR_WANT_READ ||
279 errval == SSL_ERROR_WANT_WRITE) {
283 lprintf(9, "SSL_read got error %ld\n", errval);
285 return (client_read_to
286 (&buf[len], bytes - len, timeout));
295 * CtdlStartTLS() starts SSL/TLS encryption for the current session. It
296 * must be supplied with pre-generated strings for responses of "ok," "no
297 * support for TLS," and "error" so that we can use this in any protocol.
299 void CtdlStartTLS(char *ok_response, char *nosup_response,
300 char *error_response) {
302 int retval, bits, alg_bits;
305 cprintf("%s", nosup_response);
308 if (!(CC->ssl = SSL_new(ssl_ctx))) {
309 lprintf(2, "SSL_new failed: %s\n",
310 ERR_reason_error_string(ERR_get_error()));
311 cprintf("%s", error_response);
314 if (!(SSL_set_fd(CC->ssl, CC->client_socket))) {
315 lprintf(2, "SSL_set_fd failed: %s\n",
316 ERR_reason_error_string(ERR_get_error()));
319 cprintf("%s", error_response);
322 cprintf("%s", ok_response);
323 retval = SSL_accept(CC->ssl);
326 * Can't notify the client of an error here; they will
327 * discover the problem at the SSL layer and should
328 * revert to unencrypted communications.
332 errval = SSL_get_error(CC->ssl, retval);
333 lprintf(2, "SSL_accept failed: %s\n",
334 ERR_reason_error_string(ERR_get_error()));
339 BIO_set_close(CC->ssl->rbio, BIO_NOCLOSE);
341 SSL_CIPHER_get_bits(SSL_get_current_cipher(CC->ssl),
343 lprintf(3, "SSL/TLS using %s on %s (%d of %d bits)\n",
344 SSL_CIPHER_get_name(SSL_get_current_cipher(CC->ssl)),
345 SSL_CIPHER_get_version(SSL_get_current_cipher(CC->ssl)),
347 CC->redirect_ssl = 1;
352 * cmd_stls() starts SSL/TLS encryption for the current session
354 void cmd_stls(char *params)
356 char ok_response[SIZ];
357 char nosup_response[SIZ];
358 char error_response[SIZ];
361 "%d Begin TLS negotiation now\n",
363 sprintf(nosup_response,
364 "%d TLS not supported here\n",
365 ERROR + CMD_NOT_SUPPORTED);
366 sprintf(error_response,
367 "%d TLS negotiation error\n",
368 ERROR + INTERNAL_ERROR);
370 CtdlStartTLS(ok_response, nosup_response, error_response);
375 * cmd_gtls() returns status info about the TLS connection
377 void cmd_gtls(char *params)
381 if (!CC->ssl || !CC->redirect_ssl) {
382 cprintf("%d Session is not encrypted.\n", ERROR);
386 SSL_CIPHER_get_bits(SSL_get_current_cipher(CC->ssl),
388 cprintf("%d %s|%s|%d|%d\n", CIT_OK,
389 SSL_CIPHER_get_version(SSL_get_current_cipher(CC->ssl)),
390 SSL_CIPHER_get_name(SSL_get_current_cipher(CC->ssl)),
396 * endtls() shuts down the TLS connection
398 * WARNING: This may make your session vulnerable to a known plaintext
399 * attack in the current implmentation.
403 lprintf(7, "Ending SSL/TLS\n");
406 CC->redirect_ssl = 0;
410 SSL_shutdown(CC->ssl);
413 CC->redirect_ssl = 0;
418 * ssl_lock() callback for OpenSSL mutex locks
420 void ssl_lock(int mode, int n, const char *file, int line)
422 if (mode & CRYPTO_LOCK)
423 pthread_mutex_lock(SSLCritters[n]);
425 pthread_mutex_unlock(SSLCritters[n]);
427 #endif /* HAVE_OPENSSL */