10 #include <sys/types.h>
15 #include "webserver.h"
17 #define CTDL_CRYPTO_DIR "./keys"
18 #define CTDL_KEY_PATH CTDL_CRYPTO_DIR "/citadel.key"
19 #define CTDL_CSR_PATH CTDL_CRYPTO_DIR "/citadel.csr"
20 #define CTDL_CER_PATH CTDL_CRYPTO_DIR "/citadel.cer"
24 /* Shared Diffie-Hellman parameters */
25 #define DH_P "1A74527AEE4EE2568E85D4FB2E65E18C9394B9C80C42507D7A6A0DBE9A9A54B05A9A96800C34C7AA5297095B69C88901EEFD127F969DCA26A54C0E0B5C5473EBAEB00957D2633ECAE3835775425DE66C0DE6D024DBB17445E06E6B0C78415E589B8814F08531D02FD43778451E7685541079CFFB79EF0D26EFEEBBB69D1E80383"
28 #define CIT_CIPHERS "ALL:RC4+RSA:+SSLv2:@STRENGTH" /* see ciphers(1) */
30 SSL_CTX *ssl_ctx; /* SSL context */
31 pthread_mutex_t **SSLCritters; /* Things needing locking */
33 pthread_key_t ThreadSSL; /* Per-thread SSL context */
35 static unsigned long id_callback(void)
37 return (unsigned long) pthread_self();
41 * Set up the cert things on the server side. We do need both the
42 * private key (in key_file) and the cert (in cert_file).
43 * Both files may be identical.
45 * This function is taken from OpenSSL apps/s_cb.c
48 static int ctdl_install_certificate(SSL_CTX * ctx,
49 const char *cert_file, const char *key_file)
51 if (cert_file != NULL) {
52 if (SSL_CTX_use_certificate_file(ctx, cert_file,
53 SSL_FILETYPE_PEM) <= 0) {
54 lprintf(3, "unable to get certificate from '%s'",
60 if (SSL_CTX_use_PrivateKey_file(ctx, key_file,
61 SSL_FILETYPE_PEM) <= 0) {
62 lprintf(3, "unable to get private key from '%s'",
66 /* Now we know that a key and cert have been set against
68 if (!SSL_CTX_check_private_key(ctx)) {
70 "Private key does not match the certificate public key");
80 SSL_METHOD *ssl_method;
86 EVP_PKEY *req_pkey = NULL;
87 X509_NAME *name = NULL;
90 if (!access("/var/run/egd-pool", F_OK))
91 RAND_egd("/var/run/egd-pool");
95 "PRNG not adequately seeded, won't do SSL/TLS\n");
99 malloc(CRYPTO_num_locks() * sizeof(pthread_mutex_t *));
101 lprintf(1, "citserver: can't allocate memory!!\n");
102 /* Nothing's been initialized, just die */
107 for (a = 0; a < CRYPTO_num_locks(); a++) {
108 SSLCritters[a] = malloc(sizeof(pthread_mutex_t));
109 if (!SSLCritters[a]) {
111 "citserver: can't allocate memory!!\n");
112 /* Nothing's been initialized, just die */
115 pthread_mutex_init(SSLCritters[a], NULL);
120 * Initialize SSL transport layer
123 SSL_load_error_strings();
124 ssl_method = SSLv23_server_method();
125 if (!(ssl_ctx = SSL_CTX_new(ssl_method))) {
126 lprintf(3, "SSL_CTX_new failed: %s\n",
127 ERR_reason_error_string(ERR_get_error()));
130 if (!(SSL_CTX_set_cipher_list(ssl_ctx, CIT_CIPHERS))) {
131 lprintf(3, "SSL: No ciphers available\n");
132 SSL_CTX_free(ssl_ctx);
137 #if SSLEAY_VERSION_NUMBER >= 0x00906000L
138 SSL_CTX_set_mode(ssl_ctx, SSL_CTX_get_mode(ssl_ctx) |
139 SSL_MODE_AUTO_RETRY);
143 CRYPTO_set_locking_callback(ssl_lock);
144 CRYPTO_set_id_callback(id_callback);
146 /* Load DH parameters into the context */
149 lprintf(3, "init_ssl() can't allocate a DH object: %s\n",
150 ERR_reason_error_string(ERR_get_error()));
151 SSL_CTX_free(ssl_ctx);
155 if (!(BN_hex2bn(&(dh->p), DH_P))) {
156 lprintf(3, "init_ssl() can't assign DH_P: %s\n",
157 ERR_reason_error_string(ERR_get_error()));
158 SSL_CTX_free(ssl_ctx);
162 if (!(BN_hex2bn(&(dh->g), DH_G))) {
163 lprintf(3, "init_ssl() can't assign DH_G: %s\n",
164 ERR_reason_error_string(ERR_get_error()));
165 SSL_CTX_free(ssl_ctx);
170 SSL_CTX_set_tmp_dh(ssl_ctx, dh);
173 /* Get our certificates in order.
174 * First, create the key/cert directory if it's not there already...
176 mkdir(CTDL_CRYPTO_DIR, 0700);
179 * Generate a key pair if we don't have one.
181 if (access(CTDL_KEY_PATH, R_OK) != 0) {
182 lprintf(5, "Generating RSA key pair.\n");
183 rsa = RSA_generate_key(1024, /* modulus size */
184 65537, /* exponent */
185 NULL, /* no callback */
186 NULL); /* no callback */
188 lprintf(3, "Key generation failed: %s\n",
189 ERR_reason_error_string(ERR_get_error()));
192 fp = fopen(CTDL_KEY_PATH, "w");
194 chmod(CTDL_KEY_PATH, 0600);
195 if (PEM_write_RSAPrivateKey(fp, /* the file */
198 NULL, /* no passphr */
200 NULL, /* no callbk */
203 lprintf(3, "Cannot write key: %s\n",
204 ERR_reason_error_string(ERR_get_error()));
205 unlink(CTDL_KEY_PATH);
214 * Generate a CSR if we don't have one.
216 if (access(CTDL_CSR_PATH, R_OK) != 0) {
217 lprintf(5, "Generating a certificate signing request.\n");
220 * Read our key from the file. No, we don't just keep this
221 * in memory from the above key-generation function, because
222 * there is the possibility that the key was already on disk
223 * and we didn't just generate it now.
225 fp = fopen(CTDL_KEY_PATH, "r");
227 rsa = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
233 /* Create a public key from the private key */
234 if (pk=EVP_PKEY_new(), pk != NULL) {
235 EVP_PKEY_assign_RSA(pk, rsa);
236 if (req = X509_REQ_new(), req != NULL) {
238 /* Set the public key */
239 X509_REQ_set_pubkey(req, pk);
240 X509_REQ_set_version(req, 0L);
242 name = X509_REQ_get_subject_name(req);
244 /* Tell it who we are */
247 X509_NAME_add_entry_by_txt(name, "C",
248 MBSTRING_ASC, "US", -1, -1, 0);
250 X509_NAME_add_entry_by_txt(name, "ST",
251 MBSTRING_ASC, "New York", -1, -1, 0);
253 X509_NAME_add_entry_by_txt(name, "L",
254 MBSTRING_ASC, "Mount Kisco", -1, -1, 0);
257 X509_NAME_add_entry_by_txt(name, "O",
258 MBSTRING_ASC, "FIXME.FIXME.org", -1, -1, 0);
260 X509_NAME_add_entry_by_txt(name, "OU",
261 MBSTRING_ASC, "Citadel server", -1, -1, 0);
263 X509_NAME_add_entry_by_txt(name, "CN",
264 MBSTRING_ASC, "FIXME.FIXME.org", -1, -1, 0);
266 X509_REQ_set_subject_name(req, name);
269 if (!X509_REQ_sign(req, pk, EVP_md5())) {
270 lprintf(3, "X509_REQ_sign(): error\n");
273 /* Write it to disk. */
274 fp = fopen(CTDL_CSR_PATH, "w");
276 chmod(CTDL_CSR_PATH, 0600);
277 PEM_write_X509_REQ(fp, req);
290 lprintf(3, "Unable to read private key.\n");
297 * Generate a self-signed certificate if we don't have one.
299 if (access(CTDL_CER_PATH, R_OK) != 0) {
300 lprintf(5, "Generating a self-signed certificate.\n");
302 /* Same deal as before: always read the key from disk because
303 * it may or may not have just been generated.
305 fp = fopen(CTDL_KEY_PATH, "r");
307 rsa = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
311 /* This also holds true for the CSR. */
316 if (pk=EVP_PKEY_new(), pk != NULL) {
317 EVP_PKEY_assign_RSA(pk, rsa);
320 fp = fopen(CTDL_CSR_PATH, "r");
322 req = PEM_read_X509_REQ(fp, NULL, NULL, NULL);
327 if (cer = X509_new(), cer != NULL) {
329 X509_set_issuer_name(cer, req->req_info->subject);
330 X509_set_subject_name(cer, req->req_info->subject);
331 X509_gmtime_adj(X509_get_notBefore(cer),0);
332 X509_gmtime_adj(X509_get_notAfter(cer),(long)60*60*24*SIGN_DAYS);
333 req_pkey = X509_REQ_get_pubkey(req);
334 X509_set_pubkey(cer, req_pkey);
335 EVP_PKEY_free(req_pkey);
338 if (!X509_sign(cer, pk, EVP_md5())) {
339 lprintf(3, "X509_sign(): error\n");
342 /* Write it to disk. */
343 fp = fopen(CTDL_CER_PATH, "w");
345 chmod(CTDL_CER_PATH, 0600);
346 PEM_write_X509(fp, cer);
360 * Now try to bind to the key and certificate.
362 if (ctdl_install_certificate(ssl_ctx,
366 lprintf(3, "Cannot install certificate: %s\n",
367 ERR_reason_error_string(ERR_get_error()));
374 * starttls() starts SSL/TLS encryption for the current session.
376 int starttls(int sock) {
377 int retval, bits, alg_bits;
380 pthread_setspecific(ThreadSSL, NULL);
385 if (!(newssl = SSL_new(ssl_ctx))) {
386 lprintf(3, "SSL_new failed: %s\n",
387 ERR_reason_error_string(ERR_get_error()));
390 if (!(SSL_set_fd(newssl, sock))) {
391 lprintf(3, "SSL_set_fd failed: %s\n",
392 ERR_reason_error_string(ERR_get_error()));
396 retval = SSL_accept(newssl);
399 * Can't notify the client of an error here; they will
400 * discover the problem at the SSL layer and should
401 * revert to unencrypted communications.
405 errval = SSL_get_error(newssl, retval);
406 lprintf(3, "SSL_accept failed: %s\n",
407 ERR_reason_error_string(ERR_get_error()));
412 BIO_set_close(newssl->rbio, BIO_NOCLOSE);
414 SSL_CIPHER_get_bits(SSL_get_current_cipher(newssl),
416 lprintf(5, "SSL/TLS using %s on %s (%d of %d bits)\n",
417 SSL_CIPHER_get_name(SSL_get_current_cipher(newssl)),
418 SSL_CIPHER_get_version(SSL_get_current_cipher(newssl)),
421 pthread_setspecific(ThreadSSL, newssl);
428 * endtls() shuts down the TLS connection
430 * WARNING: This may make your session vulnerable to a known plaintext
431 * attack in the current implmentation.
435 lprintf(5, "Ending SSL/TLS\n");
436 SSL_shutdown(THREADSSL);
438 pthread_setspecific(ThreadSSL, NULL);
443 * ssl_lock() callback for OpenSSL mutex locks
445 void ssl_lock(int mode, int n, const char *file, int line)
447 if (mode & CRYPTO_LOCK)
448 pthread_mutex_lock(SSLCritters[n]);
450 pthread_mutex_unlock(SSLCritters[n]);
454 * client_write_ssl() Send binary data to the client encrypted.
456 void client_write_ssl(char *buf, int nbytes)
464 while (nremain > 0) {
465 if (SSL_want_write(THREADSSL)) {
466 if ((SSL_read(THREADSSL, junk, 0)) < 1) {
467 lprintf(9, "SSL_read in client_write: %s\n", ERR_reason_error_string(ERR_get_error()));
471 SSL_write(THREADSSL, &buf[nbytes - nremain], nremain);
475 errval = SSL_get_error(THREADSSL, retval);
476 if (errval == SSL_ERROR_WANT_READ ||
477 errval == SSL_ERROR_WANT_WRITE) {
481 lprintf(9, "SSL_write got error %ld, ret %d\n", errval, retval);
483 lprintf(9, "errno is %d\n", errno);
485 client_write(&buf[nbytes - nremain], nremain);
494 * client_read_ssl() - read data from the encrypted layer.
496 int client_read_ssl(char *buf, int bytes, int timeout)
508 while (len < bytes) {
511 * This code is disabled because we don't need it when
512 * using blocking reads (which we are). -IO
515 s = BIO_get_fd(THREADSSL->rbio, NULL);
520 retval = select(s + 1, &rfds, NULL, NULL, &tv);
522 if (FD_ISSET(s, &rfds) == 0) {
527 if (SSL_want_read(THREADSSL)) {
528 if ((SSL_write(THREADSSL, junk, 0)) < 1) {
529 lprintf(9, "SSL_write in client_read: %s\n", ERR_reason_error_string(ERR_get_error()));
532 rlen = SSL_read(THREADSSL, &buf[len], bytes - len);
536 errval = SSL_get_error(THREADSSL, rlen);
537 if (errval == SSL_ERROR_WANT_READ ||
538 errval == SSL_ERROR_WANT_WRITE) {
542 lprintf(9, "SSL_read got error %ld\n", errval);
544 return (client_read_to
545 (&buf[len], bytes - len, timeout));
553 #endif /* HAVE_OPENSSL */