citadel/server/modules/crypto/serv_crypto.c

   1 // Copyright (c) 1987-2022 by the citadel.org team
   2 // This program is open source software.  Use, duplication, or disclosure is subject to the GNU General Public License v3.
   3
   4 #include <string.h>
   5 #include <unistd.h>
   6 #include <sys/stat.h>
   7 #include <sys/types.h>
   8 #include "../../sysdep.h"
   9
  10 #ifdef HAVE_OPENSSL
  11 #include <openssl/ssl.h>
  12 #include <openssl/err.h>
  13 #include <openssl/rand.h>
  14 #endif
  15
  16 #include <time.h>
  17
  18 #ifdef HAVE_PTHREAD_H
  19 #include <pthread.h>
  20 #endif
  21
  22 #ifdef HAVE_SYS_SELECT_H
  23 #include <sys/select.h>
  24 #endif
  25
  26 #include <stdio.h>
  27 #include <libcitadel.h>
  28 #include "../../server.h"
  29 #include "serv_crypto.h"
  30 #include "../../sysdep_decls.h"
  31 #include "../../citadel_defs.h"
  32 #include "../../config.h"
  33 #include "../../ctdl_module.h"
  34
  35 #ifdef HAVE_OPENSSL
  36
  37 SSL_CTX *ssl_ctx = NULL;                // This SSL context is used for all sessions.
  38 char *ssl_cipher_list = CIT_CIPHERS;
  39
  40 // If a private key does not exist, generate one now.
  41 void generate_key(char *keyfilename) {
  42         int ret = 0;
  43         RSA *rsa = NULL;
  44         BIGNUM *bne = NULL;
  45         int bits = 2048;
  46         unsigned long e = RSA_F4;
  47         FILE *fp;
  48
  49         if (access(keyfilename, R_OK) == 0) {   // Already have one.
  50                 syslog(LOG_INFO, "crypto: %s exists and is readable", keyfilename);
  51                 return;
  52         }
  53
  54         syslog(LOG_INFO, "crypto: generating RSA key pair");
  55
  56         // generate rsa key
  57         bne = BN_new();
  58         ret = BN_set_word(bne,e);
  59         if (ret != 1) {
  60                 goto free_all;
  61         }
  62
  63         rsa = RSA_new();
  64         ret = RSA_generate_key_ex(rsa, bits, bne, NULL);
  65         if (ret != 1) {
  66                 goto free_all;
  67         }
  68
  69         // write the key file
  70         fp = fopen(keyfilename, "w");
  71         if (fp != NULL) {
  72                 chmod(keyfilename, 0600);
  73                 if (PEM_write_RSAPrivateKey(fp, // the file
  74                                         rsa,    // the key
  75                                         NULL,   // no enc
  76                                         NULL,   // no passphrase
  77                                         0,      // no passphrase
  78                                         NULL,   // no callback
  79                                         NULL    // no callback
  80                 ) != 1) {
  81                         syslog(LOG_ERR, "crypto: cannot write key: %s", ERR_reason_error_string(ERR_get_error()));
  82                         unlink(keyfilename);
  83                 }
  84                 fclose(fp);
  85         }
  86
  87         // free the memory we used
  88 free_all:
  89         RSA_free(rsa);
  90         BN_free(bne);
  91 }
  92
  93
  94 // If a certificate does not exist, generate a self-signed one now.
  95 void generate_certificate(char *keyfilename, char *certfilename) {
  96         RSA *private_key = NULL;
  97         EVP_PKEY *public_key = NULL;
  98         X509_REQ *certificate_signing_request = NULL;
  99         X509_NAME *name = NULL;
 100         X509 *certificate = NULL;
 101         FILE *fp;
 102
 103         if (access(certfilename, R_OK) == 0) {                  // already have one.
 104                 syslog(LOG_INFO, "crypto: %s exists and is readable", certfilename);
 105                 return;
 106         }
 107
 108         syslog(LOG_INFO, "crypto: generating a self-signed certificate");
 109
 110         // Read in our private key.
 111         fp = fopen(keyfilename, "r");
 112         if (fp) {
 113                 private_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
 114                 fclose(fp);
 115         }
 116
 117         if (!private_key) {
 118                 syslog(LOG_ERR, "crypto: cannot read the private key");
 119                 return;
 120         }
 121
 122         // Create a public key from the private key
 123         public_key = EVP_PKEY_new();
 124         if (!public_key) {
 125                 syslog(LOG_ERR, "crypto: cannot allocate public key");
 126                 RSA_free(private_key);
 127                 return;
 128         }
 129         EVP_PKEY_assign_RSA(public_key, private_key);
 130
 131         // Create a certificate signing request
 132         certificate_signing_request = X509_REQ_new();
 133         if (!certificate_signing_request) {
 134                 syslog(LOG_ERR, "crypto: cannot allocate certificate signing request");
 135                 RSA_free(private_key);
 136                 EVP_PKEY_free(public_key);
 137                 return;
 138         }
 139
 140         // Assign the public key to the certificate signing request
 141         X509_REQ_set_pubkey(certificate_signing_request, public_key);
 142         X509_REQ_set_version(certificate_signing_request, 0L);
 143
 144         // Tell it who we are
 145         name = X509_REQ_get_subject_name(certificate_signing_request);
 146         X509_NAME_add_entry_by_txt(name, "C", MBSTRING_ASC, (unsigned const char *)"ZZ", -1, -1, 0);
 147         X509_NAME_add_entry_by_txt(name, "ST", MBSTRING_ASC, (unsigned const char *)"The World", -1, -1, 0);
 148         X509_NAME_add_entry_by_txt(name, "L", MBSTRING_ASC, (unsigned const char *)"My Location", -1, -1, 0);
 149         X509_NAME_add_entry_by_txt(name, "O", MBSTRING_ASC, (unsigned const char *)"Generic certificate", -1, -1, 0);
 150         X509_NAME_add_entry_by_txt(name, "OU", MBSTRING_ASC, (unsigned const char *)"Citadel server", -1, -1, 0);
 151         X509_NAME_add_entry_by_txt(name, "CN", MBSTRING_ASC, (unsigned const char *)"*", -1, -1, 0);
 152         X509_REQ_set_subject_name(certificate_signing_request, name);
 153
 154         // Sign the CSR
 155         //if (!X509_REQ_sign(certificate_signing_request, public_key, EVP_md5())) {
 156         if (!X509_REQ_sign(certificate_signing_request, public_key, EVP_md5()) , 0) {
 157                 syslog(LOG_ERR, "crypto: X509_REQ_sign(): error");
 158                 X509_REQ_free(certificate_signing_request);
 159                 RSA_free(private_key);
 160                 EVP_PKEY_free(public_key);
 161                 return;
 162         }
 163
 164         // Generate the self-signed certificate
 165         certificate = X509_new();
 166         if (!certificate) {
 167                 syslog(LOG_ERR, "crypto: cannot allocate X.509 certificate");
 168                 X509_REQ_free(certificate_signing_request);
 169                 RSA_free(private_key);
 170                 EVP_PKEY_free(public_key);
 171                 return;
 172         }
 173
 174         ASN1_INTEGER_set(X509_get_serialNumber(certificate), 0);
 175         X509_set_issuer_name(certificate, X509_REQ_get_subject_name(certificate_signing_request));
 176         X509_set_subject_name(certificate, X509_REQ_get_subject_name(certificate_signing_request));
 177         X509_gmtime_adj(X509_get_notBefore(certificate), 0);
 178         X509_gmtime_adj(X509_get_notAfter(certificate), (long)60*60*24*SIGN_DAYS);
 179         X509_set_pubkey(certificate, public_key);
 180         X509_REQ_free(certificate_signing_request);             // We're done with the CSR; free it
 181
 182         // Finally, sign the certificate with our private key.
 183         if (!X509_sign(certificate, public_key, EVP_md5())) {
 184                 syslog(LOG_ERR, "crypto: X509_sign() error");
 185                 X509_free(certificate);
 186                 RSA_free(private_key);
 187                 EVP_PKEY_free(public_key);
 188                 return;
 189         }
 190
 191         // Write the certificate to disk
 192         fp = fopen(certfilename, "w");
 193         if (fp != NULL) {
 194                 chmod(certfilename, 0600);
 195                 PEM_write_X509(fp, certificate);
 196                 fclose(fp);
 197         }
 198         else {
 199                 syslog(LOG_ERR, "crypto: %s: %m", certfilename);
 200         }
 201
 202         X509_free(certificate);
 203         EVP_PKEY_free(public_key);
 204         // do not RSA_free(private_key); because it was freed by EVP_PKEY_free() above
 205 }
 206
 207
 208 // Set the private key and certificate chain for the global SSL Context.
 209 // This is called during initialization, and can be called again later if the certificate changes.
 210 void bind_to_key_and_certificate(void) {
 211
 212         SSL_CTX *old_ctx = NULL;
 213         SSL_CTX *new_ctx = NULL;
 214
 215         const SSL_METHOD *method = SSLv23_server_method();
 216         if (!method) {
 217                 syslog(LOG_ERR, "crypto: SSLv23_server_method() failed: %s", ERR_reason_error_string(ERR_get_error()));
 218                 return;
 219         }
 220
 221         new_ctx = SSL_CTX_new(method);
 222         if (!new_ctx) {
 223                 syslog(LOG_ERR, "crypto: SSL_CTX_new failed: %s", ERR_reason_error_string(ERR_get_error()));
 224                 return;
 225         }
 226
 227         if (!(SSL_CTX_set_cipher_list(new_ctx, ssl_cipher_list))) {
 228                 syslog(LOG_ERR, "crypto: SSL_CTX_set_cipher_list failed: %s", ERR_reason_error_string(ERR_get_error()));
 229                 return;
 230         }
 231
 232         syslog(LOG_DEBUG, "crypto: using certificate chain %s", file_crpt_file_cer);
 233         if (!SSL_CTX_use_certificate_chain_file(new_ctx, file_crpt_file_cer)) {
 234                 syslog(LOG_ERR, "crypto: SSL_CTX_use_certificate_chain_file failed: %s", ERR_reason_error_string(ERR_get_error()));
 235                 return;
 236         }
 237
 238         syslog(LOG_DEBUG, "crypto: using private key %s", file_crpt_file_key);
 239         if (!SSL_CTX_use_PrivateKey_file(new_ctx, file_crpt_file_key, SSL_FILETYPE_PEM)) {
 240                 syslog(LOG_ERR, "crypto: SSL_CTX_use_PrivateKey_file failed: %s", ERR_reason_error_string(ERR_get_error()));
 241                 return;
 242         }
 243
 244         old_ctx = ssl_ctx;
 245         ssl_ctx = new_ctx;              // All future binds will use the new certificate
 246
 247         if (old_ctx != NULL) {
 248                 sleep(1);               // Hopefully wait until all in-progress binds to the old certificate have completed
 249                 SSL_CTX_free(old_ctx);
 250         }
 251 }
 252
 253
 254 // Check the modification time of the key and certificate files.  Reload if either one changed.
 255 void update_key_and_cert_if_needed(void) {
 256         static time_t previous_mtime = 0;
 257         struct stat keystat;
 258         struct stat certstat;
 259
 260         if (stat(file_crpt_file_key, &keystat) != 0) {
 261                 syslog(LOG_ERR, "%s: %s", file_crpt_file_key, strerror(errno));
 262                 return;
 263         }
 264         if (stat(file_crpt_file_cer, &certstat) != 0) {
 265                 syslog(LOG_ERR, "%s: %s", file_crpt_file_cer, strerror(errno));
 266                 return;
 267         }
 268
 269         if ((keystat.st_mtime + certstat.st_mtime) != previous_mtime) {
 270                 begin_critical_section(S_OPENSSL);
 271                 bind_to_key_and_certificate();
 272                 end_critical_section(S_OPENSSL);
 273                 previous_mtime = keystat.st_mtime + certstat.st_mtime;
 274         }
 275 }
 276
 277
 278 // Initialize the TLS subsystem.
 279 void init_ssl(void) {
 280
 281         // Initialize the OpenSSL library
 282         SSL_library_init();
 283         SSL_load_error_strings();
 284
 285         // Load (or generate) a key and certificate
 286         mkdir(ctdl_key_dir, 0700);                                      // If the keys directory does not exist, create it
 287         generate_key(file_crpt_file_key);                               // If a private key does not exist, create it
 288         generate_certificate(file_crpt_file_key, file_crpt_file_cer);   // If a certificate does not exist, create it
 289         bind_to_key_and_certificate();                                  // Load key and cert from disk, and bind to them.
 290
 291         // Register some Citadel protocol commands for dealing with encrypted sessions
 292         CtdlRegisterProtoHook(cmd_stls, "STLS", "Start TLS session");
 293         CtdlRegisterProtoHook(cmd_gtls, "GTLS", "Get TLS session status");
 294         CtdlRegisterSessionHook(endtls, EVT_STOP, PRIO_STOP + 10);
 295 }
 296
 297
 298 // client_write_ssl() Send binary data to the client encrypted.
 299 void client_write_ssl(const char *buf, int nbytes) {
 300         int retval;
 301         int nremain;
 302         char junk[1];
 303
 304         nremain = nbytes;
 305
 306         while (nremain > 0) {
 307                 if (SSL_want_write(CC->ssl)) {
 308                         if ((SSL_read(CC->ssl, junk, 0)) < 1) {
 309                                 syslog(LOG_DEBUG, "crypto: SSL_read in client_write: %s", ERR_reason_error_string(ERR_get_error()));
 310                         }
 311                 }
 312                 retval =
 313                     SSL_write(CC->ssl, &buf[nbytes - nremain], nremain);
 314                 if (retval < 1) {
 315                         long errval;
 316
 317                         errval = SSL_get_error(CC->ssl, retval);
 318                         if (errval == SSL_ERROR_WANT_READ || errval == SSL_ERROR_WANT_WRITE) {
 319                                 sleep(1);
 320                                 continue;
 321                         }
 322                         syslog(LOG_DEBUG, "crypto: SSL_write got error %ld, ret %d", errval, retval);
 323                         if (retval == -1) {
 324                                 syslog(LOG_DEBUG, "crypto: errno is %d", errno);
 325                         }
 326                         endtls();
 327                         client_write(&buf[nbytes - nremain], nremain);
 328                         return;
 329                 }
 330                 nremain -= retval;
 331         }
 332 }
 333
 334
 335 // read data from the encrypted layer.
 336 int client_read_sslbuffer(StrBuf *buf, int timeout) {
 337         char sbuf[16384];       // OpenSSL communicates in 16k blocks, so let's speak its native tongue.
 338         int rlen;
 339         char junk[1];
 340         SSL *pssl = CC->ssl;
 341
 342         if (pssl == NULL) return(-1);
 343
 344         while (1) {
 345                 if (SSL_want_read(pssl)) {
 346                         if ((SSL_write(pssl, junk, 0)) < 1) {
 347                                 syslog(LOG_DEBUG, "crypto: SSL_write in client_read");
 348                         }
 349                 }
 350                 rlen = SSL_read(pssl, sbuf, sizeof(sbuf));
 351                 if (rlen < 1) {
 352                         long errval;
 353
 354                         errval = SSL_get_error(pssl, rlen);
 355                         if (errval == SSL_ERROR_WANT_READ || errval == SSL_ERROR_WANT_WRITE) {
 356                                 sleep(1);
 357                                 continue;
 358                         }
 359                         syslog(LOG_DEBUG, "crypto: SSL_read got error %ld", errval);
 360                         endtls();
 361                         return (-1);
 362                 }
 363                 StrBufAppendBufPlain(buf, sbuf, rlen, 0);
 364                 return rlen;
 365         }
 366         return (0);
 367 }
 368
 369
 370 int client_readline_sslbuffer(StrBuf *Line, StrBuf *IOBuf, const char **Pos, int timeout) {
 371         const char *pos = NULL;
 372         const char *pLF;
 373         int len, rlen;
 374         int nSuccessLess = 0;
 375         const char *pch = NULL;
 376
 377         if ((Line == NULL) || (Pos == NULL) || (IOBuf == NULL)) {
 378                 if (Pos != NULL) {
 379                         *Pos = NULL;
 380                 }
 381                 return -1;
 382         }
 383
 384         pos = *Pos;
 385         if ((StrLength(IOBuf) > 0) && (pos != NULL) && (pos < ChrPtr(IOBuf) + StrLength(IOBuf))) {
 386                 pch = pos;
 387                 pch = strchr(pch, '\n');
 388
 389                 if (pch == NULL) {
 390                         StrBufAppendBufPlain(Line, pos, StrLength(IOBuf) - (pos - ChrPtr(IOBuf)), 0);
 391                         FlushStrBuf(IOBuf);
 392                         *Pos = NULL;
 393                 }
 394                 else {
 395                         int n = 0;
 396                         if ((pch > ChrPtr(IOBuf)) && (*(pch - 1) == '\r')) {
 397                                 n = 1;
 398                         }
 399                         StrBufAppendBufPlain(Line, pos, (pch - pos - n), 0);
 400
 401                         if (StrLength(IOBuf) <= (pch - ChrPtr(IOBuf) + 1)) {
 402                                 FlushStrBuf(IOBuf);
 403                                 *Pos = NULL;
 404                         }
 405                         else {
 406                                 *Pos = pch + 1;
 407                         }
 408                         return StrLength(Line);
 409                 }
 410         }
 411
 412         pLF = NULL;
 413         while ((nSuccessLess < timeout) && (pLF == NULL) && (CC->ssl != NULL)) {
 414
 415                 rlen = client_read_sslbuffer(IOBuf, timeout);
 416                 if (rlen < 1) {
 417                         return -1;
 418                 }
 419                 else if (rlen > 0) {
 420                         pLF = strchr(ChrPtr(IOBuf), '\n');
 421                 }
 422         }
 423         *Pos = NULL;
 424         if (pLF != NULL) {
 425                 pos = ChrPtr(IOBuf);
 426                 len = pLF - pos;
 427                 if (len > 0 && (*(pLF - 1) == '\r') )
 428                         len --;
 429                 StrBufAppendBufPlain(Line, pos, len, 0);
 430                 if (pLF + 1 >= ChrPtr(IOBuf) + StrLength(IOBuf)) {
 431                         FlushStrBuf(IOBuf);
 432                 }
 433                 else  {
 434                         *Pos = pLF + 1;
 435                 }
 436                 return StrLength(Line);
 437         }
 438         return -1;
 439 }
 440
 441
 442 int client_read_sslblob(StrBuf *Target, long bytes, int timeout) {
 443         long baselen;
 444         long RemainRead;
 445         int retval = 0;
 446
 447         baselen = StrLength(Target);
 448
 449         if (StrLength(CC->RecvBuf.Buf) > 0) {
 450                 long RemainLen;
 451                 long TotalLen;
 452                 const char *pchs;
 453
 454                 if (CC->RecvBuf.ReadWritePointer == NULL) {
 455                         CC->RecvBuf.ReadWritePointer = ChrPtr(CC->RecvBuf.Buf);
 456                 }
 457                 pchs = ChrPtr(CC->RecvBuf.Buf);
 458                 TotalLen = StrLength(CC->RecvBuf.Buf);
 459                 RemainLen = TotalLen - (pchs - CC->RecvBuf.ReadWritePointer);
 460                 if (RemainLen > bytes) {
 461                         RemainLen = bytes;
 462                 }
 463                 if (RemainLen > 0) {
 464                         StrBufAppendBufPlain(Target, CC->RecvBuf.ReadWritePointer, RemainLen, 0);
 465                         CC->RecvBuf.ReadWritePointer += RemainLen;
 466                 }
 467                 if ((ChrPtr(CC->RecvBuf.Buf) + StrLength(CC->RecvBuf.Buf)) <= CC->RecvBuf.ReadWritePointer) {
 468                         CC->RecvBuf.ReadWritePointer = NULL;
 469                         FlushStrBuf(CC->RecvBuf.Buf);
 470                 }
 471         }
 472
 473         if (StrLength(Target) >= bytes + baselen) {
 474                 return 1;
 475         }
 476
 477         CC->RecvBuf.ReadWritePointer = NULL;
 478
 479         while ((StrLength(Target) < bytes + baselen) && (retval >= 0)) {
 480                 retval = client_read_sslbuffer(CC->RecvBuf.Buf, timeout);
 481                 if (retval >= 0) {
 482                         RemainRead = bytes - (StrLength (Target) - baselen);
 483                         if (RemainRead < StrLength(CC->RecvBuf.Buf)) {
 484                                 StrBufAppendBufPlain(
 485                                         Target,
 486                                         ChrPtr(CC->RecvBuf.Buf),
 487                                         RemainRead, 0);
 488                                 CC->RecvBuf.ReadWritePointer = ChrPtr(CC->RecvBuf.Buf) + RemainRead;
 489                                 break;
 490                         }
 491                         StrBufAppendBuf(Target, CC->RecvBuf.Buf, 0);
 492                         FlushStrBuf(CC->RecvBuf.Buf);
 493                 }
 494                 else {
 495                         FlushStrBuf(CC->RecvBuf.Buf);
 496                         return -1;
 497
 498                 }
 499         }
 500         return 1;
 501 }
 502
 503
 504 // CtdlStartTLS() starts TLS encryption for the current session.  It
 505 // must be supplied with pre-generated strings for responses of "ok," "no
 506 // support for TLS," and "error" so that we can use this in any protocol.
 507 void CtdlStartTLS(char *ok_response, char *nosup_response, char *error_response) {
 508         int retval, bits, alg_bits;
 509
 510         if (CC->redirect_ssl) {
 511                 syslog(LOG_ERR, "crypto: attempt to begin SSL on an already encrypted connection");
 512                 if (error_response != NULL) {
 513                         cprintf("%s", error_response);
 514                 }
 515                 return;
 516         }
 517
 518         if (!ssl_ctx) {
 519                 syslog(LOG_ERR, "crypto: SSL failed: ../../context.has not been initialized");
 520                 if (nosup_response != NULL) {
 521                         cprintf("%s", nosup_response);
 522                 }
 523                 return;
 524         }
 525
 526         update_key_and_cert_if_needed();                // did someone update the key or cert?  if so, re-bind them
 527
 528         if (!(CC->ssl = SSL_new(ssl_ctx))) {
 529                 syslog(LOG_ERR, "crypto: SSL_new failed: %s", ERR_reason_error_string(ERR_get_error()));
 530                 if (error_response != NULL) {
 531                         cprintf("%s", error_response);
 532                 }
 533                 return;
 534         }
 535         if (!(SSL_set_fd(CC->ssl, CC->client_socket))) {
 536                 syslog(LOG_ERR, "crypto: SSL_set_fd failed: %s", ERR_reason_error_string(ERR_get_error()));
 537                 SSL_free(CC->ssl);
 538                 CC->ssl = NULL;
 539                 if (error_response != NULL) {
 540                         cprintf("%s", error_response);
 541                 }
 542                 return;
 543         }
 544         if (ok_response != NULL) {
 545                 cprintf("%s", ok_response);
 546         }
 547         retval = SSL_accept(CC->ssl);
 548         if (retval < 1) {
 549                 // Can't notify the client of an error here; they will
 550                 // discover the problem at the SSL layer and should
 551                 // revert to unencrypted communications.
 552                 syslog(LOG_ERR, "crypto: SSL_accept failed: %s", ERR_reason_error_string(ERR_get_error()));
 553                 SSL_free(CC->ssl);
 554                 CC->ssl = NULL;
 555                 return;
 556         }
 557         bits = SSL_CIPHER_get_bits(SSL_get_current_cipher(CC->ssl), &alg_bits);
 558         syslog(LOG_INFO, "crypto: TLS using %s on %s (%d of %d bits)",
 559                 SSL_CIPHER_get_name(SSL_get_current_cipher(CC->ssl)),
 560                 SSL_CIPHER_get_version(SSL_get_current_cipher(CC->ssl)),
 561                 bits, alg_bits
 562         );
 563         CC->redirect_ssl = 1;
 564 }
 565
 566
 567 // cmd_stls() starts TLS encryption for the current session
 568 void cmd_stls(char *params) {
 569         char ok_response[SIZ];
 570         char nosup_response[SIZ];
 571         char error_response[SIZ];
 572
 573         unbuffer_output();
 574
 575         sprintf(ok_response, "%d Begin TLS negotiation now\n", CIT_OK);
 576         sprintf(nosup_response, "%d TLS not supported here\n", ERROR + CMD_NOT_SUPPORTED);
 577         sprintf(error_response, "%d TLS negotiation error\n", ERROR + INTERNAL_ERROR);
 578
 579         CtdlStartTLS(ok_response, nosup_response, error_response);
 580 }
 581
 582
 583 // cmd_gtls() returns status info about the TLS connection
 584 void cmd_gtls(char *params) {
 585         int bits, alg_bits;
 586
 587         if (!CC->ssl || !CC->redirect_ssl) {
 588                 cprintf("%d Session is not encrypted.\n", ERROR);
 589                 return;
 590         }
 591         bits = SSL_CIPHER_get_bits(SSL_get_current_cipher(CC->ssl), &alg_bits);
 592         cprintf("%d %s|%s|%d|%d\n", CIT_OK,
 593                 SSL_CIPHER_get_version(SSL_get_current_cipher(CC->ssl)),
 594                 SSL_CIPHER_get_name(SSL_get_current_cipher(CC->ssl)),
 595                 alg_bits, bits);
 596 }
 597
 598
 599 // endtls() shuts down the TLS connection
 600 void endtls(void) {
 601         if (!CC->ssl) {
 602                 CC->redirect_ssl = 0;
 603                 return;
 604         }
 605
 606         syslog(LOG_INFO, "crypto: ending TLS on this session");
 607         SSL_shutdown(CC->ssl);
 608         SSL_free(CC->ssl);
 609         CC->ssl = NULL;
 610         CC->redirect_ssl = 0;
 611 }
 612
 613 #endif  // HAVE_OPENSSL