1 /* Copyright (c) 2003, Roger Dingledine.
2 * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
3 * Copyright (c) 2007-2010, The Tor Project, Inc. */
4 /* See LICENSE for licensing information */
8 * \brief Wrapper functions to present a consistent interface to
9 * TLS, SSL, and X.509 functions from OpenSSL.
12 /* (Unlike other tor functions, these
13 * are prefixed with tor_ in order to avoid conflicting with OpenSSL
14 * functions and variables.)
20 #include <openssl/ssl.h>
21 #include <openssl/ssl3.h>
22 #include <openssl/err.h>
23 #include <openssl/tls1.h>
24 #include <openssl/asn1.h>
25 #include <openssl/bio.h>
26 #include <openssl/opensslv.h>
28 #if OPENSSL_VERSION_NUMBER < 0x00907000l
29 #error "We require OpenSSL >= 0.9.7"
32 #define CRYPTO_PRIVATE /* to import prototypes from crypto.h */
38 #include "container.h"
42 /* Enable the "v2" TLS handshake.
44 #define V2_HANDSHAKE_SERVER
45 #define V2_HANDSHAKE_CLIENT
47 /* Copied from or.h */
48 #define LEGAL_NICKNAME_CHARACTERS \
49 "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
51 /** How long do identity certificates live? (sec) */
52 #define IDENTITY_CERT_LIFETIME (365*24*60*60)
54 #define ADDR(tls) (((tls) && (tls)->address) ? tls->address : "peer")
56 /* We redefine these so that we can run correctly even if the vendor gives us
57 * a version of OpenSSL that does not match its header files. (Apple: I am
60 #ifndef SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION
61 #define SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION 0x00040000L
63 #ifndef SSL3_FLAGS_ALLOW_UNSAFE_LEGACY_RENEGOTIATION
64 #define SSL3_FLAGS_ALLOW_UNSAFE_LEGACY_RENEGOTIATION 0x0010
67 /** Does the run-time openssl version look like we need
68 * SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION? */
69 static int use_unsafe_renegotiation_op
= 0;
70 /** Does the run-time openssl version look like we need
71 * SSL3_FLAGS_ALLOW_UNSAFE_LEGACY_RENEGOTIATION? */
72 static int use_unsafe_renegotiation_flag
= 0;
74 /** Structure holding the TLS state for a single connection. */
75 typedef struct tor_tls_context_t
{
83 /** Holds a SSL object and its associated data. Members are only
84 * accessed from within tortls.c.
87 HT_ENTRY(tor_tls_t
) node
;
88 tor_tls_context_t
*context
; /** A link to the context object for this tls. */
89 SSL
*ssl
; /**< An OpenSSL SSL object. */
90 int socket
; /**< The underlying file descriptor for this TLS connection. */
91 char *address
; /**< An address to log when describing this connection. */
93 TOR_TLS_ST_HANDSHAKE
, TOR_TLS_ST_OPEN
, TOR_TLS_ST_GOTCLOSE
,
94 TOR_TLS_ST_SENTCLOSE
, TOR_TLS_ST_CLOSED
, TOR_TLS_ST_RENEGOTIATE
,
95 } state
: 3; /**< The current SSL state, depending on which operations have
96 * completed successfully. */
97 unsigned int isServer
:1; /**< True iff this is a server-side connection */
98 unsigned int wasV2Handshake
:1; /**< True iff the original handshake for
99 * this connection used the updated version
100 * of the connection protocol (client sends
101 * different cipher list, server sends only
102 * one certificate). */
103 /** True iff we should call negotiated_callback when we're done reading. */
104 unsigned int got_renegotiate
:1;
105 size_t wantwrite_n
; /**< 0 normally, >0 if we returned wantwrite last
107 /** Last values retrieved from BIO_number_read()/write(); see
108 * tor_tls_get_n_raw_bytes() for usage.
110 unsigned long last_write_count
;
111 unsigned long last_read_count
;
112 /** If set, a callback to invoke whenever the client tries to renegotiate
114 void (*negotiated_callback
)(tor_tls_t
*tls
, void *arg
);
115 /** Argument to pass to negotiated_callback. */
119 #ifdef V2_HANDSHAKE_CLIENT
120 /** An array of fake SSL_CIPHER objects that we use in order to trick OpenSSL
121 * in client mode into advertising the ciphers we want. See
122 * rectify_client_ciphers() for details. */
123 static SSL_CIPHER
*CLIENT_CIPHER_DUMMIES
= NULL
;
124 /** A stack of SSL_CIPHER objects, some real, some fake.
125 * See rectify_client_ciphers() for details. */
126 static STACK_OF(SSL_CIPHER
) *CLIENT_CIPHER_STACK
= NULL
;
129 /** Helper: compare tor_tls_t objects by its SSL. */
131 tor_tls_entries_eq(const tor_tls_t
*a
, const tor_tls_t
*b
)
133 return a
->ssl
== b
->ssl
;
136 /** Helper: return a hash value for a tor_tls_t by its SSL. */
137 static INLINE
unsigned int
138 tor_tls_entry_hash(const tor_tls_t
*a
)
140 #if SIZEOF_INT == SIZEOF_VOID_P
141 return ((unsigned int)(uintptr_t)a
->ssl
);
143 return (unsigned int) ((((uint64_t)a
->ssl
)>>2) & UINT_MAX
);
147 /** Map from SSL* pointers to tor_tls_t objects using those pointers.
149 static HT_HEAD(tlsmap
, tor_tls_t
) tlsmap_root
= HT_INITIALIZER();
151 HT_PROTOTYPE(tlsmap
, tor_tls_t
, node
, tor_tls_entry_hash
,
153 HT_GENERATE(tlsmap
, tor_tls_t
, node
, tor_tls_entry_hash
,
154 tor_tls_entries_eq
, 0.6, malloc
, realloc
, free
)
156 /** Helper: given a SSL* pointer, return the tor_tls_t object using that
158 static INLINE tor_tls_t
*
159 tor_tls_get_by_ssl(const SSL
*ssl
)
161 tor_tls_t search
, *result
;
162 memset(&search
, 0, sizeof(search
));
163 search
.ssl
= (SSL
*)ssl
;
164 result
= HT_FIND(tlsmap
, &tlsmap_root
, &search
);
168 static void tor_tls_context_decref(tor_tls_context_t
*ctx
);
169 static void tor_tls_context_incref(tor_tls_context_t
*ctx
);
170 static X509
* tor_tls_create_certificate(crypto_pk_env_t
*rsa
,
171 crypto_pk_env_t
*rsa_sign
,
173 const char *cname_sign
,
174 unsigned int lifetime
);
175 static void tor_tls_unblock_renegotiation(tor_tls_t
*tls
);
177 /** Global tls context. We keep it here because nobody else needs to
179 static tor_tls_context_t
*global_tls_context
= NULL
;
180 /** True iff tor_tls_init() has been called. */
181 static int tls_library_is_initialized
= 0;
183 /* Module-internal error codes. */
184 #define _TOR_TLS_SYSCALL (_MIN_TOR_TLS_ERROR_VAL - 2)
185 #define _TOR_TLS_ZERORETURN (_MIN_TOR_TLS_ERROR_VAL - 1)
187 /** Log all pending tls errors at level <b>severity</b>. Use
188 * <b>doing</b> to describe our current activities.
191 tls_log_errors(tor_tls_t
*tls
, int severity
, const char *doing
)
194 const char *msg
, *lib
, *func
, *addr
;
195 addr
= tls
? tls
->address
: NULL
;
196 while ((err
= ERR_get_error()) != 0) {
197 msg
= (const char*)ERR_reason_error_string(err
);
198 lib
= (const char*)ERR_lib_error_string(err
);
199 func
= (const char*)ERR_func_error_string(err
);
200 if (!msg
) msg
= "(null)";
201 if (!lib
) lib
= "(null)";
202 if (!func
) func
= "(null)";
204 log(severity
, LD_NET
, "TLS error while %s%s%s: %s (in %s:%s)",
205 doing
, addr
?" with ":"", addr
?addr
:"",
208 log(severity
, LD_NET
, "TLS error%s%s: %s (in %s:%s)",
209 addr
?" with ":"", addr
?addr
:"",
215 /** Convert an errno (or a WSAerrno on windows) into a TOR_TLS_* error
218 tor_errno_to_tls_error(int e
)
220 #if defined(MS_WINDOWS)
222 case WSAECONNRESET
: // most common
223 return TOR_TLS_ERROR_CONNRESET
;
225 return TOR_TLS_ERROR_TIMEOUT
;
227 case WSAEHOSTUNREACH
:
228 return TOR_TLS_ERROR_NO_ROUTE
;
229 case WSAECONNREFUSED
:
230 return TOR_TLS_ERROR_CONNREFUSED
; // least common
232 return TOR_TLS_ERROR_MISC
;
236 case ECONNRESET
: // most common
237 return TOR_TLS_ERROR_CONNRESET
;
239 return TOR_TLS_ERROR_TIMEOUT
;
242 return TOR_TLS_ERROR_NO_ROUTE
;
244 return TOR_TLS_ERROR_CONNREFUSED
; // least common
246 return TOR_TLS_ERROR_MISC
;
251 /** Given a TOR_TLS_* error code, return a string equivalent. */
253 tor_tls_err_to_string(int err
)
256 return "[Not an error.]";
258 case TOR_TLS_ERROR_MISC
: return "misc error";
259 case TOR_TLS_ERROR_IO
: return "unexpected close";
260 case TOR_TLS_ERROR_CONNREFUSED
: return "connection refused";
261 case TOR_TLS_ERROR_CONNRESET
: return "connection reset";
262 case TOR_TLS_ERROR_NO_ROUTE
: return "host unreachable";
263 case TOR_TLS_ERROR_TIMEOUT
: return "connection timed out";
264 case TOR_TLS_CLOSE
: return "closed";
265 case TOR_TLS_WANTREAD
: return "want to read";
266 case TOR_TLS_WANTWRITE
: return "want to write";
267 default: return "(unknown error code)";
271 #define CATCH_SYSCALL 1
274 /** Given a TLS object and the result of an SSL_* call, use
275 * SSL_get_error to determine whether an error has occurred, and if so
276 * which one. Return one of TOR_TLS_{DONE|WANTREAD|WANTWRITE|ERROR}.
277 * If extra&CATCH_SYSCALL is true, return _TOR_TLS_SYSCALL instead of
278 * reporting syscall errors. If extra&CATCH_ZERO is true, return
279 * _TOR_TLS_ZERORETURN instead of reporting zero-return errors.
281 * If an error has occurred, log it at level <b>severity</b> and describe the
282 * current action as <b>doing</b>.
285 tor_tls_get_error(tor_tls_t
*tls
, int r
, int extra
,
286 const char *doing
, int severity
)
288 int err
= SSL_get_error(tls
->ssl
, r
);
289 int tor_error
= TOR_TLS_ERROR_MISC
;
293 case SSL_ERROR_WANT_READ
:
294 return TOR_TLS_WANTREAD
;
295 case SSL_ERROR_WANT_WRITE
:
296 return TOR_TLS_WANTWRITE
;
297 case SSL_ERROR_SYSCALL
:
298 if (extra
&CATCH_SYSCALL
)
299 return _TOR_TLS_SYSCALL
;
301 log(severity
, LD_NET
, "TLS error: unexpected close while %s", doing
);
302 tor_error
= TOR_TLS_ERROR_IO
;
304 int e
= tor_socket_errno(tls
->socket
);
305 log(severity
, LD_NET
,
306 "TLS error: <syscall error while %s> (errno=%d: %s)",
307 doing
, e
, tor_socket_strerror(e
));
308 tor_error
= tor_errno_to_tls_error(e
);
310 tls_log_errors(tls
, severity
, doing
);
312 case SSL_ERROR_ZERO_RETURN
:
313 if (extra
&CATCH_ZERO
)
314 return _TOR_TLS_ZERORETURN
;
315 log(severity
, LD_NET
, "TLS connection closed while %s", doing
);
316 tls_log_errors(tls
, severity
, doing
);
317 return TOR_TLS_CLOSE
;
319 tls_log_errors(tls
, severity
, doing
);
320 return TOR_TLS_ERROR_MISC
;
324 /** Initialize OpenSSL, unless it has already been initialized.
329 if (!tls_library_is_initialized
) {
332 SSL_load_error_strings();
333 crypto_global_init(-1);
337 /* OpenSSL 0.9.8l introdeced SSL3_FLAGS_ALLOW_UNSAGE_LEGACY_RENEGOTIATION
338 * here, but without thinking too hard about it: it turns out that the
339 * flag in question needed to be set at the last minute, and that it
340 * conflicted with an existing flag number that had already been added
341 * in the OpenSSL 1.0.0 betas. OpenSSL 0.9.8m thoughtfully replaced
342 * the flag with an option and (it seems) broke anything that used
343 * SSL3_FLAGS_* for the purpose. So we need to know how to do both,
344 * and we mustn't use the SSL3_FLAGS option with anything besides
347 * No, we can't just set flag 0x0010 everywhere. It breaks Tor with
348 * OpenSSL 1.0.0beta3 and later. No, we can't just set option
349 * 0x00040000L everywhere: before 0.9.8m, it meant something else.
351 * No, we can't simply detect whether the flag or the option is present
352 * in the headers at build-time: some vendors (notably Apple) like to
353 * leave their headers out of sync with their libraries.
355 * Yes, it _is_ almost as if the OpenSSL developers decided that no
356 * program should be allowed to use renegotiation its first passed an
357 * test of intelligence and determination.
359 if (version
>= 0x009080c0L
&& version
< 0x009080d0L
) {
360 log_notice(LD_GENERAL
, "OpenSSL %s looks like version 0.9.8l; "
361 "I will try SSL3_FLAGS to enable renegotation.",
362 SSLeay_version(SSLEAY_VERSION
));
363 use_unsafe_renegotiation_flag
= 1;
364 use_unsafe_renegotiation_op
= 1;
365 } else if (version
>= 0x009080d0L
) {
366 log_notice(LD_GENERAL
, "OpenSSL %s looks like version 0.9.8m or later; "
367 "I will try SSL_OP to enable renegotiation",
368 SSLeay_version(SSLEAY_VERSION
));
369 use_unsafe_renegotiation_op
= 1;
370 } else if (version
< 0x009080c0L
) {
371 log_notice(LD_GENERAL
, "OpenSSL %s [%lx] looks like it's older than "
372 "0.9.8l, but some vendors have backported 0.9.8l's "
373 "renegotiation code to earlier versions. I'll set "
374 "SSL3_FLAGS just to be safe.",
375 SSLeay_version(SSLEAY_VERSION
), version
);
376 use_unsafe_renegotiation_flag
= 1;
378 log_info(LD_GENERAL
, "OpenSSL %s has version %lx",
379 SSLeay_version(SSLEAY_VERSION
), version
);
382 tls_library_is_initialized
= 1;
386 /** Free all global TLS structures. */
388 tor_tls_free_all(void)
390 if (global_tls_context
) {
391 tor_tls_context_decref(global_tls_context
);
392 global_tls_context
= NULL
;
394 if (!HT_EMPTY(&tlsmap_root
)) {
395 log_warn(LD_MM
, "Still have entries in the tlsmap at shutdown.");
397 HT_CLEAR(tlsmap
, &tlsmap_root
);
398 #ifdef V2_HANDSHAKE_CLIENT
399 if (CLIENT_CIPHER_DUMMIES
)
400 tor_free(CLIENT_CIPHER_DUMMIES
);
401 if (CLIENT_CIPHER_STACK
)
402 sk_SSL_CIPHER_free(CLIENT_CIPHER_STACK
);
406 /** We need to give OpenSSL a callback to verify certificates. This is
407 * it: We always accept peer certs and complete the handshake. We
408 * don't validate them until later.
411 always_accept_verify_cb(int preverify_ok
,
412 X509_STORE_CTX
*x509_ctx
)
419 /** Return a newly allocated X509 name with commonName <b>cname</b>. */
421 tor_x509_name_new(const char *cname
)
425 if (!(name
= X509_NAME_new()))
427 if ((nid
= OBJ_txt2nid("commonName")) == NID_undef
) goto error
;
428 if (!(X509_NAME_add_entry_by_NID(name
, nid
, MBSTRING_ASC
,
429 (unsigned char*)cname
, -1, -1, 0)))
433 X509_NAME_free(name
);
437 /** Generate and sign an X509 certificate with the public key <b>rsa</b>,
438 * signed by the private key <b>rsa_sign</b>. The commonName of the
439 * certificate will be <b>cname</b>; the commonName of the issuer will be
440 * <b>cname_sign</b>. The cert will be valid for <b>cert_lifetime</b> seconds
441 * starting from now. Return a certificate on success, NULL on
445 tor_tls_create_certificate(crypto_pk_env_t
*rsa
,
446 crypto_pk_env_t
*rsa_sign
,
448 const char *cname_sign
,
449 unsigned int cert_lifetime
)
451 time_t start_time
, end_time
;
452 EVP_PKEY
*sign_pkey
= NULL
, *pkey
=NULL
;
454 X509_NAME
*name
= NULL
, *name_issuer
=NULL
;
458 start_time
= time(NULL
);
462 tor_assert(rsa_sign
);
463 tor_assert(cname_sign
);
464 if (!(sign_pkey
= _crypto_pk_env_get_evp_pkey(rsa_sign
,1)))
466 if (!(pkey
= _crypto_pk_env_get_evp_pkey(rsa
,0)))
468 if (!(x509
= X509_new()))
470 if (!(X509_set_version(x509
, 2)))
472 if (!(ASN1_INTEGER_set(X509_get_serialNumber(x509
), (long)start_time
)))
475 if (!(name
= tor_x509_name_new(cname
)))
477 if (!(X509_set_subject_name(x509
, name
)))
479 if (!(name_issuer
= tor_x509_name_new(cname_sign
)))
481 if (!(X509_set_issuer_name(x509
, name_issuer
)))
484 if (!X509_time_adj(X509_get_notBefore(x509
),0,&start_time
))
486 end_time
= start_time
+ cert_lifetime
;
487 if (!X509_time_adj(X509_get_notAfter(x509
),0,&end_time
))
489 if (!X509_set_pubkey(x509
, pkey
))
491 if (!X509_sign(x509
, sign_pkey
, EVP_sha1()))
501 tls_log_errors(NULL
, LOG_WARN
, "generating certificate");
503 EVP_PKEY_free(sign_pkey
);
507 X509_NAME_free(name
);
509 X509_NAME_free(name_issuer
);
513 /** List of ciphers that servers should select from.*/
514 #define SERVER_CIPHER_LIST \
515 (TLS1_TXT_DHE_RSA_WITH_AES_256_SHA ":" \
516 TLS1_TXT_DHE_RSA_WITH_AES_128_SHA ":" \
517 SSL3_TXT_EDH_RSA_DES_192_CBC3_SHA)
518 /* Note: for setting up your own private testing network with link crypto
519 * disabled, set the cipher lists to your cipher list to
520 * SSL3_TXT_RSA_NULL_SHA. If you do this, you won't be able to communicate
521 * with any of the "real" Tors, though. */
523 #ifdef V2_HANDSHAKE_CLIENT
524 #define CIPHER(id, name) name ":"
525 #define XCIPHER(id, name)
526 /** List of ciphers that clients should advertise, omitting items that
527 * our OpenSSL doesn't know about. */
528 static const char CLIENT_CIPHER_LIST
[] =
529 #include "./ciphers.inc"
534 /** Holds a cipher that we want to advertise, and its 2-byte ID. */
535 typedef struct cipher_info_t
{ unsigned id
; const char *name
; } cipher_info_t
;
536 /** A list of all the ciphers that clients should advertise, including items
537 * that OpenSSL might not know about. */
538 static const cipher_info_t CLIENT_CIPHER_INFO_LIST
[] = {
539 #define CIPHER(id, name) { id, name },
540 #define XCIPHER(id, name) { id, #name },
541 #include "./ciphers.inc"
546 /** The length of CLIENT_CIPHER_INFO_LIST and CLIENT_CIPHER_DUMMIES. */
547 static const int N_CLIENT_CIPHERS
=
548 sizeof(CLIENT_CIPHER_INFO_LIST
)/sizeof(CLIENT_CIPHER_INFO_LIST
[0]);
551 #ifndef V2_HANDSHAKE_CLIENT
552 #undef CLIENT_CIPHER_LIST
553 #define CLIENT_CIPHER_LIST (TLS1_TXT_DHE_RSA_WITH_AES_128_SHA ":" \
554 SSL3_TXT_EDH_RSA_DES_192_CBC3_SHA)
557 /** Remove a reference to <b>ctx</b>, and free it if it has no more
560 tor_tls_context_decref(tor_tls_context_t
*ctx
)
563 if (--ctx
->refcnt
== 0) {
564 SSL_CTX_free(ctx
->ctx
);
565 X509_free(ctx
->my_cert
);
566 X509_free(ctx
->my_id_cert
);
567 crypto_free_pk_env(ctx
->key
);
572 /** Increase the reference count of <b>ctx</b>. */
574 tor_tls_context_incref(tor_tls_context_t
*ctx
)
579 /** Create a new TLS context for use with Tor TLS handshakes.
580 * <b>identity</b> should be set to the identity key used to sign the
581 * certificate, and <b>nickname</b> set to the nickname to use.
583 * You can call this function multiple times. Each time you call it,
584 * it generates new certificates; all new connections will use
585 * the new SSL context.
588 tor_tls_context_new(crypto_pk_env_t
*identity
, unsigned int key_lifetime
)
590 crypto_pk_env_t
*rsa
= NULL
;
591 EVP_PKEY
*pkey
= NULL
;
592 tor_tls_context_t
*result
= NULL
;
593 X509
*cert
= NULL
, *idcert
= NULL
;
594 char *nickname
= NULL
, *nn2
= NULL
;
597 nickname
= crypto_random_hostname(8, 20, "www.", ".net");
598 nn2
= crypto_random_hostname(8, 20, "www.", ".net");
600 /* Generate short-term RSA key. */
601 if (!(rsa
= crypto_new_pk_env()))
603 if (crypto_pk_generate_key(rsa
)<0)
605 /* Create certificate signed by identity key. */
606 cert
= tor_tls_create_certificate(rsa
, identity
, nickname
, nn2
,
608 /* Create self-signed certificate for identity key. */
609 idcert
= tor_tls_create_certificate(identity
, identity
, nn2
, nn2
,
610 IDENTITY_CERT_LIFETIME
);
611 if (!cert
|| !idcert
) {
612 log(LOG_WARN
, LD_CRYPTO
, "Error creating certificate");
616 result
= tor_malloc_zero(sizeof(tor_tls_context_t
));
618 result
->my_cert
= X509_dup(cert
);
619 result
->my_id_cert
= X509_dup(idcert
);
620 result
->key
= crypto_pk_dup_key(rsa
);
622 #ifdef EVERYONE_HAS_AES
623 /* Tell OpenSSL to only use TLS1 */
624 if (!(result
->ctx
= SSL_CTX_new(TLSv1_method())))
627 /* Tell OpenSSL to use SSL3 or TLS1 but not SSL2. */
628 if (!(result
->ctx
= SSL_CTX_new(SSLv23_method())))
630 SSL_CTX_set_options(result
->ctx
, SSL_OP_NO_SSLv2
);
632 SSL_CTX_set_options(result
->ctx
, SSL_OP_SINGLE_DH_USE
);
634 #ifdef SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION
635 SSL_CTX_set_options(result
->ctx
,
636 SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION
);
638 /* Yes, we know what we are doing here. No, we do not treat a renegotiation
639 * as authenticating any earlier-received data.
641 if (use_unsafe_renegotiation_op
) {
642 SSL_CTX_set_options(result
->ctx
,
643 SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION
);
645 /* Don't actually allow compression; it uses ram and time, but the data
646 * we transmit is all encrypted anyway. */
647 if (result
->ctx
->comp_methods
)
648 result
->ctx
->comp_methods
= NULL
;
649 #ifdef SSL_MODE_RELEASE_BUFFERS
650 SSL_CTX_set_mode(result
->ctx
, SSL_MODE_RELEASE_BUFFERS
);
652 if (cert
&& !SSL_CTX_use_certificate(result
->ctx
,cert
))
654 X509_free(cert
); /* We just added a reference to cert. */
657 X509_STORE
*s
= SSL_CTX_get_cert_store(result
->ctx
);
659 X509_STORE_add_cert(s
, idcert
);
660 X509_free(idcert
); /* The context now owns the reference to idcert */
663 SSL_CTX_set_session_cache_mode(result
->ctx
, SSL_SESS_CACHE_OFF
);
665 if (!(pkey
= _crypto_pk_env_get_evp_pkey(rsa
,1)))
667 if (!SSL_CTX_use_PrivateKey(result
->ctx
, pkey
))
671 if (!SSL_CTX_check_private_key(result
->ctx
))
674 crypto_dh_env_t
*dh
= crypto_dh_new();
675 SSL_CTX_set_tmp_dh(result
->ctx
, _crypto_dh_env_get_dh(dh
));
678 SSL_CTX_set_verify(result
->ctx
, SSL_VERIFY_PEER
,
679 always_accept_verify_cb
);
680 /* let us realloc bufs that we're writing from */
681 SSL_CTX_set_mode(result
->ctx
, SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER
);
682 /* Free the old context if one exists. */
683 if (global_tls_context
) {
684 /* This is safe even if there are open connections: OpenSSL does
685 * reference counting with SSL and SSL_CTX objects. */
686 tor_tls_context_decref(global_tls_context
);
688 global_tls_context
= result
;
690 crypto_free_pk_env(rsa
);
696 tls_log_errors(NULL
, LOG_WARN
, "creating TLS context");
702 crypto_free_pk_env(rsa
);
704 tor_tls_context_decref(result
);
712 #ifdef V2_HANDSHAKE_SERVER
713 /** Return true iff the cipher list suggested by the client for <b>ssl</b> is
714 * a list that indicates that the client knows how to do the v2 TLS connection
717 tor_tls_client_is_using_v2_ciphers(const SSL
*ssl
, const char *address
)
720 SSL_SESSION
*session
;
721 /* If we reached this point, we just got a client hello. See if there is
723 if (!(session
= SSL_get_session((SSL
*)ssl
))) {
724 log_warn(LD_NET
, "No session on TLS?");
727 if (!session
->ciphers
) {
728 log_warn(LD_NET
, "No ciphers on session");
731 /* Now we need to see if there are any ciphers whose presence means we're
732 * dealing with an updated Tor. */
733 for (i
= 0; i
< sk_SSL_CIPHER_num(session
->ciphers
); ++i
) {
734 SSL_CIPHER
*cipher
= sk_SSL_CIPHER_value(session
->ciphers
, i
);
735 const char *ciphername
= SSL_CIPHER_get_name(cipher
);
736 if (strcmp(ciphername
, TLS1_TXT_DHE_RSA_WITH_AES_128_SHA
) &&
737 strcmp(ciphername
, TLS1_TXT_DHE_RSA_WITH_AES_256_SHA
) &&
738 strcmp(ciphername
, SSL3_TXT_EDH_RSA_DES_192_CBC3_SHA
) &&
739 strcmp(ciphername
, "(NONE)")) {
740 /* XXXX should be ld_debug */
741 log_info(LD_NET
, "Got a non-version-1 cipher called '%s'", ciphername
);
749 smartlist_t
*elts
= smartlist_create();
751 for (i
= 0; i
< sk_SSL_CIPHER_num(session
->ciphers
); ++i
) {
752 SSL_CIPHER
*cipher
= sk_SSL_CIPHER_value(session
->ciphers
, i
);
753 const char *ciphername
= SSL_CIPHER_get_name(cipher
);
754 smartlist_add(elts
, (char*)ciphername
);
756 s
= smartlist_join_strings(elts
, ":", 0, NULL
);
757 log_info(LD_NET
, "Got a non-version-1 cipher list from %s. It is: '%s'",
760 smartlist_free(elts
);
765 /** Invoked when we're accepting a connection on <b>ssl</b>, and the connection
766 * changes state. We use this:
767 * <ul><li>To alter the state of the handshake partway through, so we
768 * do not send or request extra certificates in v2 handshakes.</li>
769 * <li>To detect renegotiation</li></ul>
772 tor_tls_server_info_callback(const SSL
*ssl
, int type
, int val
)
776 if (type
!= SSL_CB_ACCEPT_LOOP
)
778 if (ssl
->state
!= SSL3_ST_SW_SRVR_HELLO_A
)
781 tls
= tor_tls_get_by_ssl(ssl
);
783 /* Check whether we're watching for renegotiates. If so, this is one! */
784 if (tls
->negotiated_callback
)
785 tls
->got_renegotiate
= 1;
787 log_warn(LD_BUG
, "Couldn't look up the tls for an SSL*. How odd!");
790 /* Now check the cipher list. */
791 if (tor_tls_client_is_using_v2_ciphers(ssl
, ADDR(tls
))) {
792 /*XXXX_TLS keep this from happening more than once! */
794 /* Yes, we're casting away the const from ssl. This is very naughty of us.
795 * Let's hope openssl doesn't notice! */
797 /* Set SSL_MODE_NO_AUTO_CHAIN to keep from sending back any extra certs. */
798 SSL_set_mode((SSL
*) ssl
, SSL_MODE_NO_AUTO_CHAIN
);
799 /* Don't send a hello request. */
800 SSL_set_verify((SSL
*) ssl
, SSL_VERIFY_NONE
, NULL
);
803 tls
->wasV2Handshake
= 1;
805 log_warn(LD_BUG
, "Couldn't look up the tls for an SSL*. How odd!");
811 /** Replace *<b>ciphers</b> with a new list of SSL ciphersuites: specifically,
812 * a list designed to mimic a common web browser. Some of the ciphers in the
813 * list won't actually be implemented by OpenSSL: that's okay so long as the
814 * server doesn't select them, and the server won't select anything besides
815 * what's in SERVER_CIPHER_LIST.
817 * [If the server <b>does</b> select a bogus cipher, we won't crash or
818 * anything; we'll just fail later when we try to look up the cipher in
819 * ssl->cipher_list_by_id.]
822 rectify_client_ciphers(STACK_OF(SSL_CIPHER
) **ciphers
)
824 #ifdef V2_HANDSHAKE_CLIENT
825 if (PREDICT_UNLIKELY(!CLIENT_CIPHER_STACK
)) {
826 /* We need to set CLIENT_CIPHER_STACK to an array of the ciphers
830 /* First, create a dummy SSL_CIPHER for every cipher. */
831 CLIENT_CIPHER_DUMMIES
=
832 tor_malloc_zero(sizeof(SSL_CIPHER
)*N_CLIENT_CIPHERS
);
833 for (i
=0; i
< N_CLIENT_CIPHERS
; ++i
) {
834 CLIENT_CIPHER_DUMMIES
[i
].valid
= 1;
835 CLIENT_CIPHER_DUMMIES
[i
].id
= CLIENT_CIPHER_INFO_LIST
[i
].id
| (3<<24);
836 CLIENT_CIPHER_DUMMIES
[i
].name
= CLIENT_CIPHER_INFO_LIST
[i
].name
;
839 CLIENT_CIPHER_STACK
= sk_SSL_CIPHER_new_null();
840 tor_assert(CLIENT_CIPHER_STACK
);
842 log_debug(LD_NET
, "List was: %s", CLIENT_CIPHER_LIST
);
843 for (j
= 0; j
< sk_SSL_CIPHER_num(*ciphers
); ++j
) {
844 SSL_CIPHER
*cipher
= sk_SSL_CIPHER_value(*ciphers
, j
);
845 log_debug(LD_NET
, "Cipher %d: %lx %s", j
, cipher
->id
, cipher
->name
);
848 /* Then copy as many ciphers as we can from the good list, inserting
849 * dummies as needed. */
851 for (i
= 0; i
< N_CLIENT_CIPHERS
; ) {
852 SSL_CIPHER
*cipher
= NULL
;
853 if (j
< sk_SSL_CIPHER_num(*ciphers
))
854 cipher
= sk_SSL_CIPHER_value(*ciphers
, j
);
855 if (cipher
&& ((cipher
->id
>> 24) & 0xff) != 3) {
856 log_debug(LD_NET
, "Skipping v2 cipher %s", cipher
->name
);
859 (cipher
->id
& 0xffff) == CLIENT_CIPHER_INFO_LIST
[i
].id
) {
860 log_debug(LD_NET
, "Found cipher %s", cipher
->name
);
861 sk_SSL_CIPHER_push(CLIENT_CIPHER_STACK
, cipher
);
865 log_debug(LD_NET
, "Inserting fake %s", CLIENT_CIPHER_DUMMIES
[i
].name
);
866 sk_SSL_CIPHER_push(CLIENT_CIPHER_STACK
, &CLIENT_CIPHER_DUMMIES
[i
]);
872 sk_SSL_CIPHER_free(*ciphers
);
873 *ciphers
= sk_SSL_CIPHER_dup(CLIENT_CIPHER_STACK
);
874 tor_assert(*ciphers
);
881 /** Create a new TLS object from a file descriptor, and a flag to
882 * determine whether it is functioning as a server.
885 tor_tls_new(int sock
, int isServer
)
888 tor_tls_t
*result
= tor_malloc_zero(sizeof(tor_tls_t
));
890 tor_assert(global_tls_context
); /* make sure somebody made it first */
891 if (!(result
->ssl
= SSL_new(global_tls_context
->ctx
))) {
892 tls_log_errors(NULL
, LOG_WARN
, "generating TLS context");
897 #ifdef SSL_set_tlsext_host_name
898 /* Browsers use the TLS hostname extension, so we should too. */
900 char *fake_hostname
= crypto_random_hostname(4,25, "www.",".com");
901 SSL_set_tlsext_host_name(result
->ssl
, fake_hostname
);
902 tor_free(fake_hostname
);
906 if (!SSL_set_cipher_list(result
->ssl
,
907 isServer
? SERVER_CIPHER_LIST
: CLIENT_CIPHER_LIST
)) {
908 tls_log_errors(NULL
, LOG_WARN
, "setting ciphers");
909 #ifdef SSL_set_tlsext_host_name
910 SSL_set_tlsext_host_name(result
->ssl
, NULL
);
912 SSL_free(result
->ssl
);
917 rectify_client_ciphers(&result
->ssl
->cipher_list
);
918 result
->socket
= sock
;
919 bio
= BIO_new_socket(sock
, BIO_NOCLOSE
);
921 tls_log_errors(NULL
, LOG_WARN
, "opening BIO");
922 #ifdef SSL_set_tlsext_host_name
923 SSL_set_tlsext_host_name(result
->ssl
, NULL
);
925 SSL_free(result
->ssl
);
929 HT_INSERT(tlsmap
, &tlsmap_root
, result
);
930 SSL_set_bio(result
->ssl
, bio
, bio
);
931 tor_tls_context_incref(global_tls_context
);
932 result
->context
= global_tls_context
;
933 result
->state
= TOR_TLS_ST_HANDSHAKE
;
934 result
->isServer
= isServer
;
935 result
->wantwrite_n
= 0;
936 result
->last_write_count
= BIO_number_written(bio
);
937 result
->last_read_count
= BIO_number_read(bio
);
938 if (result
->last_write_count
|| result
->last_read_count
) {
939 log_warn(LD_NET
, "Newly created BIO has read count %lu, write count %lu",
940 result
->last_read_count
, result
->last_write_count
);
942 #ifdef V2_HANDSHAKE_SERVER
944 SSL_set_info_callback(result
->ssl
, tor_tls_server_info_callback
);
948 /* Not expected to get called. */
949 tls_log_errors(NULL
, LOG_WARN
, "generating TLS context");
953 /** Make future log messages about <b>tls</b> display the address
957 tor_tls_set_logged_address(tor_tls_t
*tls
, const char *address
)
960 tor_free(tls
->address
);
961 tls
->address
= tor_strdup(address
);
964 /** Set <b>cb</b> to be called with argument <b>arg</b> whenever <b>tls</b>
965 * next gets a client-side renegotiate in the middle of a read. Do not
966 * invoke this function until <em>after</em> initial handshaking is done!
969 tor_tls_set_renegotiate_callback(tor_tls_t
*tls
,
970 void (*cb
)(tor_tls_t
*, void *arg
),
973 tls
->negotiated_callback
= cb
;
974 tls
->callback_arg
= arg
;
975 tls
->got_renegotiate
= 0;
976 #ifdef V2_HANDSHAKE_SERVER
978 SSL_set_info_callback(tls
->ssl
, tor_tls_server_info_callback
);
980 SSL_set_info_callback(tls
->ssl
, NULL
);
985 /** If this version of openssl requires it, turn on renegotiation on
989 tor_tls_unblock_renegotiation(tor_tls_t
*tls
)
991 /* Yes, we know what we are doing here. No, we do not treat a renegotiation
992 * as authenticating any earlier-received data. */
993 if (use_unsafe_renegotiation_flag
) {
994 tls
->ssl
->s3
->flags
|= SSL3_FLAGS_ALLOW_UNSAFE_LEGACY_RENEGOTIATION
;
996 if (use_unsafe_renegotiation_op
) {
997 SSL_set_options(tls
->ssl
,
998 SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION
);
1002 /** If this version of openssl supports it, turn off renegotiation on
1003 * <b>tls</b>. (Our protocol never requires this for security, but it's nice
1004 * to use belt-and-suspenders here.)
1007 tor_tls_block_renegotiation(tor_tls_t
*tls
)
1009 tls
->ssl
->s3
->flags
&= ~SSL3_FLAGS_ALLOW_UNSAFE_LEGACY_RENEGOTIATION
;
1012 /** Return whether this tls initiated the connect (client) or
1013 * received it (server). */
1015 tor_tls_is_server(tor_tls_t
*tls
)
1018 return tls
->isServer
;
1021 /** Release resources associated with a TLS object. Does not close the
1022 * underlying file descriptor.
1025 tor_tls_free(tor_tls_t
*tls
)
1028 tor_assert(tls
&& tls
->ssl
);
1029 removed
= HT_REMOVE(tlsmap
, &tlsmap_root
, tls
);
1031 log_warn(LD_BUG
, "Freeing a TLS that was not in the ssl->tls map.");
1033 #ifdef SSL_set_tlsext_host_name
1034 SSL_set_tlsext_host_name(tls
->ssl
, NULL
);
1038 tls
->negotiated_callback
= NULL
;
1040 tor_tls_context_decref(tls
->context
);
1041 tor_free(tls
->address
);
1045 /** Underlying function for TLS reading. Reads up to <b>len</b>
1046 * characters from <b>tls</b> into <b>cp</b>. On success, returns the
1047 * number of characters read. On failure, returns TOR_TLS_ERROR,
1048 * TOR_TLS_CLOSE, TOR_TLS_WANTREAD, or TOR_TLS_WANTWRITE.
1051 tor_tls_read(tor_tls_t
*tls
, char *cp
, size_t len
)
1055 tor_assert(tls
->ssl
);
1056 tor_assert(tls
->state
== TOR_TLS_ST_OPEN
);
1057 tor_assert(len
<INT_MAX
);
1058 r
= SSL_read(tls
->ssl
, cp
, (int)len
);
1060 #ifdef V2_HANDSHAKE_SERVER
1061 if (tls
->got_renegotiate
) {
1062 /* Renegotiation happened! */
1063 log_info(LD_NET
, "Got a TLS renegotiation from %s", ADDR(tls
));
1064 if (tls
->negotiated_callback
)
1065 tls
->negotiated_callback(tls
, tls
->callback_arg
);
1066 tls
->got_renegotiate
= 0;
1071 err
= tor_tls_get_error(tls
, r
, CATCH_ZERO
, "reading", LOG_DEBUG
);
1072 if (err
== _TOR_TLS_ZERORETURN
|| err
== TOR_TLS_CLOSE
) {
1073 log_debug(LD_NET
,"read returned r=%d; TLS is closed",r
);
1074 tls
->state
= TOR_TLS_ST_CLOSED
;
1075 return TOR_TLS_CLOSE
;
1077 tor_assert(err
!= TOR_TLS_DONE
);
1078 log_debug(LD_NET
,"read returned r=%d, err=%d",r
,err
);
1083 /** Underlying function for TLS writing. Write up to <b>n</b>
1084 * characters from <b>cp</b> onto <b>tls</b>. On success, returns the
1085 * number of characters written. On failure, returns TOR_TLS_ERROR,
1086 * TOR_TLS_WANTREAD, or TOR_TLS_WANTWRITE.
1089 tor_tls_write(tor_tls_t
*tls
, const char *cp
, size_t n
)
1093 tor_assert(tls
->ssl
);
1094 tor_assert(tls
->state
== TOR_TLS_ST_OPEN
);
1095 tor_assert(n
< INT_MAX
);
1098 if (tls
->wantwrite_n
) {
1099 /* if WANTWRITE last time, we must use the _same_ n as before */
1100 tor_assert(n
>= tls
->wantwrite_n
);
1101 log_debug(LD_NET
,"resuming pending-write, (%d to flush, reusing %d)",
1102 (int)n
, (int)tls
->wantwrite_n
);
1103 n
= tls
->wantwrite_n
;
1104 tls
->wantwrite_n
= 0;
1106 r
= SSL_write(tls
->ssl
, cp
, (int)n
);
1107 err
= tor_tls_get_error(tls
, r
, 0, "writing", LOG_INFO
);
1108 if (err
== TOR_TLS_DONE
) {
1111 if (err
== TOR_TLS_WANTWRITE
|| err
== TOR_TLS_WANTREAD
) {
1112 tls
->wantwrite_n
= n
;
1117 /** Perform initial handshake on <b>tls</b>. When finished, returns
1118 * TOR_TLS_DONE. On failure, returns TOR_TLS_ERROR, TOR_TLS_WANTREAD,
1119 * or TOR_TLS_WANTWRITE.
1122 tor_tls_handshake(tor_tls_t
*tls
)
1126 tor_assert(tls
->ssl
);
1127 tor_assert(tls
->state
== TOR_TLS_ST_HANDSHAKE
);
1128 check_no_tls_errors();
1129 if (tls
->isServer
) {
1130 r
= SSL_accept(tls
->ssl
);
1132 r
= SSL_connect(tls
->ssl
);
1134 /* We need to call this here and not earlier, since OpenSSL has a penchant
1135 * for clearing its flags when you say accept or connect. */
1136 tor_tls_unblock_renegotiation(tls
);
1137 r
= tor_tls_get_error(tls
,r
,0, "handshaking", LOG_INFO
);
1138 if (ERR_peek_error() != 0) {
1139 tls_log_errors(tls
, tls
->isServer
? LOG_INFO
: LOG_WARN
,
1141 return TOR_TLS_ERROR_MISC
;
1143 if (r
== TOR_TLS_DONE
) {
1144 tls
->state
= TOR_TLS_ST_OPEN
;
1145 if (tls
->isServer
) {
1146 SSL_set_info_callback(tls
->ssl
, NULL
);
1147 SSL_set_verify(tls
->ssl
, SSL_VERIFY_PEER
, always_accept_verify_cb
);
1148 /* There doesn't seem to be a clear OpenSSL API to clear mode flags. */
1149 tls
->ssl
->mode
&= ~SSL_MODE_NO_AUTO_CHAIN
;
1150 #ifdef V2_HANDSHAKE_SERVER
1151 if (tor_tls_client_is_using_v2_ciphers(tls
->ssl
, ADDR(tls
))) {
1152 /* This check is redundant, but back when we did it in the callback,
1153 * we might have not been able to look up the tor_tls_t if the code
1154 * was buggy. Fixing that. */
1155 if (!tls
->wasV2Handshake
) {
1156 log_warn(LD_BUG
, "For some reason, wasV2Handshake didn't"
1157 " get set. Fixing that.");
1159 tls
->wasV2Handshake
= 1;
1160 log_debug(LD_NET
, "Completed V2 TLS handshake with client; waiting "
1161 "for renegotiation.");
1163 tls
->wasV2Handshake
= 0;
1167 #ifdef V2_HANDSHAKE_CLIENT
1168 /* If we got no ID cert, we're a v2 handshake. */
1169 X509
*cert
= SSL_get_peer_certificate(tls
->ssl
);
1170 STACK_OF(X509
) *chain
= SSL_get_peer_cert_chain(tls
->ssl
);
1171 int n_certs
= sk_X509_num(chain
);
1172 if (n_certs
> 1 || (n_certs
== 1 && cert
!= sk_X509_value(chain
, 0)))
1173 tls
->wasV2Handshake
= 0;
1175 log_debug(LD_NET
, "Server sent back a single certificate; looks like "
1176 "a v2 handshake on %p.", tls
);
1177 tls
->wasV2Handshake
= 1;
1182 if (SSL_set_cipher_list(tls
->ssl
, SERVER_CIPHER_LIST
) == 0) {
1183 tls_log_errors(NULL
, LOG_WARN
, "re-setting ciphers");
1184 r
= TOR_TLS_ERROR_MISC
;
1191 /** Client only: Renegotiate a TLS session. When finished, returns
1192 * TOR_TLS_DONE. On failure, returns TOR_TLS_ERROR, TOR_TLS_WANTREAD, or
1193 * TOR_TLS_WANTWRITE.
1196 tor_tls_renegotiate(tor_tls_t
*tls
)
1200 /* We could do server-initiated renegotiation too, but that would be tricky.
1201 * Instead of "SSL_renegotiate, then SSL_do_handshake until done" */
1202 tor_assert(!tls
->isServer
);
1203 if (tls
->state
!= TOR_TLS_ST_RENEGOTIATE
) {
1204 int r
= SSL_renegotiate(tls
->ssl
);
1206 return tor_tls_get_error(tls
, r
, 0, "renegotiating", LOG_WARN
);
1208 tls
->state
= TOR_TLS_ST_RENEGOTIATE
;
1210 r
= SSL_do_handshake(tls
->ssl
);
1212 tls
->state
= TOR_TLS_ST_OPEN
;
1213 return TOR_TLS_DONE
;
1215 return tor_tls_get_error(tls
, r
, 0, "renegotiating handshake", LOG_INFO
);
1218 /** Shut down an open tls connection <b>tls</b>. When finished, returns
1219 * TOR_TLS_DONE. On failure, returns TOR_TLS_ERROR, TOR_TLS_WANTREAD,
1220 * or TOR_TLS_WANTWRITE.
1223 tor_tls_shutdown(tor_tls_t
*tls
)
1228 tor_assert(tls
->ssl
);
1231 if (tls
->state
== TOR_TLS_ST_SENTCLOSE
) {
1232 /* If we've already called shutdown once to send a close message,
1233 * we read until the other side has closed too.
1236 r
= SSL_read(tls
->ssl
, buf
, 128);
1238 err
= tor_tls_get_error(tls
, r
, CATCH_ZERO
, "reading to shut down",
1240 if (err
== _TOR_TLS_ZERORETURN
) {
1241 tls
->state
= TOR_TLS_ST_GOTCLOSE
;
1242 /* fall through... */
1248 r
= SSL_shutdown(tls
->ssl
);
1250 /* If shutdown returns 1, the connection is entirely closed. */
1251 tls
->state
= TOR_TLS_ST_CLOSED
;
1252 return TOR_TLS_DONE
;
1254 err
= tor_tls_get_error(tls
, r
, CATCH_SYSCALL
|CATCH_ZERO
, "shutting down",
1256 if (err
== _TOR_TLS_SYSCALL
) {
1257 /* The underlying TCP connection closed while we were shutting down. */
1258 tls
->state
= TOR_TLS_ST_CLOSED
;
1259 return TOR_TLS_DONE
;
1260 } else if (err
== _TOR_TLS_ZERORETURN
) {
1261 /* The TLS connection says that it sent a shutdown record, but
1262 * isn't done shutting down yet. Make sure that this hasn't
1263 * happened before, then go back to the start of the function
1266 if (tls
->state
== TOR_TLS_ST_GOTCLOSE
||
1267 tls
->state
== TOR_TLS_ST_SENTCLOSE
) {
1268 log(LOG_WARN
, LD_NET
,
1269 "TLS returned \"half-closed\" value while already half-closed");
1270 return TOR_TLS_ERROR_MISC
;
1272 tls
->state
= TOR_TLS_ST_SENTCLOSE
;
1273 /* fall through ... */
1280 /** Return true iff this TLS connection is authenticated.
1283 tor_tls_peer_has_cert(tor_tls_t
*tls
)
1286 cert
= SSL_get_peer_certificate(tls
->ssl
);
1287 tls_log_errors(tls
, LOG_WARN
, "getting peer certificate");
1294 /** Warn that a certificate lifetime extends through a certain range. */
1296 log_cert_lifetime(X509
*cert
, const char *problem
)
1300 char *s1
=NULL
, *s2
=NULL
;
1302 time_t now
= time(NULL
);
1306 log_warn(LD_GENERAL
,
1307 "Certificate %s: is your system clock set incorrectly?",
1310 if (!(bio
= BIO_new(BIO_s_mem()))) {
1311 log_warn(LD_GENERAL
, "Couldn't allocate BIO!"); goto end
;
1313 if (!(ASN1_TIME_print(bio
, X509_get_notBefore(cert
)))) {
1314 tls_log_errors(NULL
, LOG_WARN
, "printing certificate lifetime");
1317 BIO_get_mem_ptr(bio
, &buf
);
1318 s1
= tor_strndup(buf
->data
, buf
->length
);
1320 (void)BIO_reset(bio
);
1321 if (!(ASN1_TIME_print(bio
, X509_get_notAfter(cert
)))) {
1322 tls_log_errors(NULL
, LOG_WARN
, "printing certificate lifetime");
1325 BIO_get_mem_ptr(bio
, &buf
);
1326 s2
= tor_strndup(buf
->data
, buf
->length
);
1328 strftime(mytime
, 32, "%b %d %H:%M:%S %Y GMT", tor_gmtime_r(&now
, &tm
));
1330 log_warn(LD_GENERAL
,
1331 "(certificate lifetime runs from %s through %s. Your time is %s.)",
1335 /* Not expected to get invoked */
1336 tls_log_errors(NULL
, LOG_WARN
, "getting certificate lifetime");
1345 /** Helper function: try to extract a link certificate and an identity
1346 * certificate from <b>tls</b>, and store them in *<b>cert_out</b> and
1347 * *<b>id_cert_out</b> respectively. Log all messages at level
1350 * Note that a reference is added to cert_out, so it needs to be
1351 * freed. id_cert_out doesn't. */
1353 try_to_extract_certs_from_tls(int severity
, tor_tls_t
*tls
,
1354 X509
**cert_out
, X509
**id_cert_out
)
1356 X509
*cert
= NULL
, *id_cert
= NULL
;
1357 STACK_OF(X509
) *chain
= NULL
;
1358 int num_in_chain
, i
;
1359 *cert_out
= *id_cert_out
= NULL
;
1361 if (!(cert
= SSL_get_peer_certificate(tls
->ssl
)))
1364 if (!(chain
= SSL_get_peer_cert_chain(tls
->ssl
)))
1366 num_in_chain
= sk_X509_num(chain
);
1367 /* 1 means we're receiving (server-side), and it's just the id_cert.
1368 * 2 means we're connecting (client-side), and it's both the link
1369 * cert and the id_cert.
1371 if (num_in_chain
< 1) {
1372 log_fn(severity
,LD_PROTOCOL
,
1373 "Unexpected number of certificates in chain (%d)",
1377 for (i
=0; i
<num_in_chain
; ++i
) {
1378 id_cert
= sk_X509_value(chain
, i
);
1379 if (X509_cmp(id_cert
, cert
) != 0)
1382 *id_cert_out
= id_cert
;
1385 /** If the provided tls connection is authenticated and has a
1386 * certificate chain that is currently valid and signed, then set
1387 * *<b>identity_key</b> to the identity certificate's key and return
1388 * 0. Else, return -1 and log complaints with log-level <b>severity</b>.
1391 tor_tls_verify(int severity
, tor_tls_t
*tls
, crypto_pk_env_t
**identity_key
)
1393 X509
*cert
= NULL
, *id_cert
= NULL
;
1394 EVP_PKEY
*id_pkey
= NULL
;
1398 *identity_key
= NULL
;
1400 try_to_extract_certs_from_tls(severity
, tls
, &cert
, &id_cert
);
1404 log_fn(severity
,LD_PROTOCOL
,"No distinct identity certificate found");
1407 if (!(id_pkey
= X509_get_pubkey(id_cert
)) ||
1408 X509_verify(cert
, id_pkey
) <= 0) {
1409 log_fn(severity
,LD_PROTOCOL
,"X509_verify on cert and pkey returned <= 0");
1410 tls_log_errors(tls
, severity
,"verifying certificate");
1414 rsa
= EVP_PKEY_get1_RSA(id_pkey
);
1417 *identity_key
= _crypto_new_pk_env_rsa(rsa
);
1425 EVP_PKEY_free(id_pkey
);
1427 /* This should never get invoked, but let's make sure in case OpenSSL
1428 * acts unexpectedly. */
1429 tls_log_errors(tls
, LOG_WARN
, "finishing tor_tls_verify");
1434 /** Check whether the certificate set on the connection <b>tls</b> is
1435 * expired or not-yet-valid, give or take <b>tolerance</b>
1436 * seconds. Return 0 for valid, -1 for failure.
1438 * NOTE: you should call tor_tls_verify before tor_tls_check_lifetime.
1441 tor_tls_check_lifetime(tor_tls_t
*tls
, int tolerance
)
1449 if (!(cert
= SSL_get_peer_certificate(tls
->ssl
)))
1452 t
= now
+ tolerance
;
1453 if (X509_cmp_time(X509_get_notBefore(cert
), &t
) > 0) {
1454 log_cert_lifetime(cert
, "not yet valid");
1457 t
= now
- tolerance
;
1458 if (X509_cmp_time(X509_get_notAfter(cert
), &t
) < 0) {
1459 log_cert_lifetime(cert
, "already expired");
1467 /* Not expected to get invoked */
1468 tls_log_errors(tls
, LOG_WARN
, "checking certificate lifetime");
1473 /** Return the number of bytes available for reading from <b>tls</b>.
1476 tor_tls_get_pending_bytes(tor_tls_t
*tls
)
1479 return SSL_pending(tls
->ssl
);
1482 /** If <b>tls</b> requires that the next write be of a particular size,
1483 * return that size. Otherwise, return 0. */
1485 tor_tls_get_forced_write_size(tor_tls_t
*tls
)
1487 return tls
->wantwrite_n
;
1490 /** Sets n_read and n_written to the number of bytes read and written,
1491 * respectively, on the raw socket used by <b>tls</b> since the last time this
1492 * function was called on <b>tls</b>. */
1494 tor_tls_get_n_raw_bytes(tor_tls_t
*tls
, size_t *n_read
, size_t *n_written
)
1498 r
= BIO_number_read(SSL_get_rbio(tls
->ssl
));
1499 /* We want the number of bytes actually for real written. Unfortunately,
1500 * sometimes OpenSSL replaces the wbio on tls->ssl with a buffering bio,
1501 * which makes the answer turn out wrong. Let's cope with that. Note
1502 * that this approach will fail if we ever replace tls->ssl's BIOs with
1503 * buffering bios for reasons of our own. As an alternative, we could
1504 * save the original BIO for tls->ssl in the tor_tls_t structure, but
1505 * that would be tempting fate. */
1506 wbio
= SSL_get_wbio(tls
->ssl
);
1507 if (wbio
->method
== BIO_f_buffer() && (tmpbio
= BIO_next(wbio
)) != NULL
)
1509 w
= BIO_number_written(wbio
);
1511 /* We are ok with letting these unsigned ints go "negative" here:
1512 * If we wrapped around, this should still give us the right answer, unless
1513 * we wrapped around by more than ULONG_MAX since the last time we called
1516 *n_read
= (size_t)(r
- tls
->last_read_count
);
1517 *n_written
= (size_t)(w
- tls
->last_write_count
);
1518 if (*n_read
> INT_MAX
|| *n_written
> INT_MAX
) {
1519 log_warn(LD_BUG
, "Preposterously large value in tor_tls_get_n_raw_bytes. "
1520 "r=%lu, last_read=%lu, w=%lu, last_written=%lu",
1521 r
, tls
->last_read_count
, w
, tls
->last_write_count
);
1523 tls
->last_read_count
= r
;
1524 tls
->last_write_count
= w
;
1527 /** Implement check_no_tls_errors: If there are any pending OpenSSL
1528 * errors, log an error message. */
1530 _check_no_tls_errors(const char *fname
, int line
)
1532 if (ERR_peek_error() == 0)
1534 log(LOG_WARN
, LD_CRYPTO
, "Unhandled OpenSSL errors found at %s:%d: ",
1535 tor_fix_source_file(fname
), line
);
1536 tls_log_errors(NULL
, LOG_WARN
, NULL
);
1539 /** Return true iff the initial TLS connection at <b>tls</b> did not use a v2
1540 * TLS handshake. Output is undefined if the handshake isn't finished. */
1542 tor_tls_used_v1_handshake(tor_tls_t
*tls
)
1544 if (tls
->isServer
) {
1545 #ifdef V2_HANDSHAKE_SERVER
1546 return ! tls
->wasV2Handshake
;
1549 #ifdef V2_HANDSHAKE_CLIENT
1550 return ! tls
->wasV2Handshake
;
1556 /** Examine the amount of memory used and available for buffers in <b>tls</b>.
1557 * Set *<b>rbuf_capacity</b> to the amount of storage allocated for the read
1558 * buffer and *<b>rbuf_bytes</b> to the amount actually used.
1559 * Set *<b>wbuf_capacity</b> to the amount of storage allocated for the write
1560 * buffer and *<b>wbuf_bytes</b> to the amount actually used. */
1562 tor_tls_get_buffer_sizes(tor_tls_t
*tls
,
1563 size_t *rbuf_capacity
, size_t *rbuf_bytes
,
1564 size_t *wbuf_capacity
, size_t *wbuf_bytes
)
1566 if (tls
->ssl
->s3
->rbuf
.buf
)
1567 *rbuf_capacity
= tls
->ssl
->s3
->rbuf
.len
;
1570 if (tls
->ssl
->s3
->wbuf
.buf
)
1571 *wbuf_capacity
= tls
->ssl
->s3
->wbuf
.len
;
1574 *rbuf_bytes
= tls
->ssl
->s3
->rbuf
.left
;
1575 *wbuf_bytes
= tls
->ssl
->s3
->wbuf
.left
;