| /*************************************************************************** |
| * _ _ ____ _ |
| * Project ___| | | | _ \| | |
| * / __| | | | |_) | | |
| * | (__| |_| | _ <| |___ |
| * \___|\___/|_| \_\_____| |
| * |
| * Copyright (C) 1998 - 2007, Daniel Stenberg, <daniel@haxx.se>, et al. |
| * |
| * This software is licensed as described in the file COPYING, which |
| * you should have received as part of this distribution. The terms |
| * are also available at http://curl.haxx.se/docs/copyright.html. |
| * |
| * You may opt to use, copy, modify, merge, publish, distribute and/or sell |
| * copies of the Software, and permit persons to whom the Software is |
| * furnished to do so, under the terms of the COPYING file. |
| * |
| * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY |
| * KIND, either express or implied. |
| * |
| * $Id$ |
| ***************************************************************************/ |
| |
| /* |
| * Source file for all GnuTLS-specific code for the TLS/SSL layer. No code |
| * but sslgen.c should ever call or use these functions. |
| * |
| * Note: don't use the GnuTLS' *_t variable type names in this source code, |
| * since they were not present in 1.0.X. |
| */ |
| |
| #include "setup.h" |
| #ifdef USE_GNUTLS |
| #include <gnutls/gnutls.h> |
| #include <gnutls/x509.h> |
| |
| #include <string.h> |
| #include <stdlib.h> |
| #include <ctype.h> |
| #ifdef HAVE_SYS_SOCKET_H |
| #include <sys/socket.h> |
| #endif |
| |
| #include "urldata.h" |
| #include "sendf.h" |
| #include "gtls.h" |
| #include "sslgen.h" |
| #include "parsedate.h" |
| #include "connect.h" /* for the connect timeout */ |
| #include "select.h" |
| #define _MPRINTF_REPLACE /* use our functions only */ |
| #include <curl/mprintf.h> |
| #include "memory.h" |
| /* The last #include file should be: */ |
| #include "memdebug.h" |
| |
| /* Enable GnuTLS debugging by defining GTLSDEBUG */ |
| /*#define GTLSDEBUG */ |
| |
| #ifdef GTLSDEBUG |
| static void tls_log_func(int level, const char *str) |
| { |
| fprintf(stderr, "|<%d>| %s", level, str); |
| } |
| #endif |
| static bool gtls_inited = FALSE; |
| /* |
| * Custom push and pull callback functions used by GNU TLS to read and write |
| * to the socket. These functions are simple wrappers to send() and recv() |
| * (although here using the sread/swrite macros as defined by setup_once.h). |
| * We use custom functions rather than the GNU TLS defaults because it allows |
| * us to get specific about the fourth "flags" argument, and to use arbitrary |
| * private data with gnutls_transport_set_ptr if we wish. |
| */ |
| static ssize_t Curl_gtls_push(void *s, const void *buf, size_t len) |
| { |
| return swrite(s, buf, len); |
| } |
| |
| static ssize_t Curl_gtls_pull(void *s, void *buf, size_t len) |
| { |
| return sread(s, buf, len); |
| } |
| |
| /* Global GnuTLS init, called from Curl_ssl_init() */ |
| int Curl_gtls_init(void) |
| { |
| /* Unfortunately we can not init here, things like curl --version will |
| * fail to work if there is no egd socket available because libgcrypt |
| * will EXIT the application!! |
| * By doing the actual init later (before actually trying to use GnuTLS), |
| * we can at least provide basic info etc. |
| */ |
| return 1; |
| } |
| |
| static int _Curl_gtls_init(void) |
| { |
| int ret = 1; |
| if (!gtls_inited) { |
| ret = gnutls_global_init()?0:1; |
| #ifdef GTLSDEBUG |
| gnutls_global_set_log_function(tls_log_func); |
| gnutls_global_set_log_level(2); |
| #endif |
| gtls_inited = TRUE; |
| } |
| return ret; |
| } |
| |
| int Curl_gtls_cleanup(void) |
| { |
| if (gtls_inited) |
| gnutls_global_deinit(); |
| return 1; |
| } |
| |
| static void showtime(struct SessionHandle *data, |
| const char *text, |
| time_t stamp) |
| { |
| struct tm *tm; |
| #ifdef HAVE_GMTIME_R |
| struct tm buffer; |
| tm = (struct tm *)gmtime_r(&stamp, &buffer); |
| #else |
| tm = gmtime(&stamp); |
| #endif |
| snprintf(data->state.buffer, |
| BUFSIZE, |
| "\t %s: %s, %02d %s %4d %02d:%02d:%02d GMT\n", |
| text, |
| Curl_wkday[tm->tm_wday?tm->tm_wday-1:6], |
| tm->tm_mday, |
| Curl_month[tm->tm_mon], |
| tm->tm_year + 1900, |
| tm->tm_hour, |
| tm->tm_min, |
| tm->tm_sec); |
| infof(data, "%s", data->state.buffer); |
| } |
| |
| /* this function does a BLOCKING SSL/TLS (re-)handshake */ |
| static CURLcode handshake(struct connectdata *conn, |
| gnutls_session session, |
| int sockindex, |
| bool duringconnect) |
| { |
| struct SessionHandle *data = conn->data; |
| int rc; |
| if (!gtls_inited) |
| _Curl_gtls_init(); |
| do { |
| rc = gnutls_handshake(session); |
| |
| if((rc == GNUTLS_E_AGAIN) || (rc == GNUTLS_E_INTERRUPTED)) { |
| long timeout_ms = DEFAULT_CONNECT_TIMEOUT; |
| long has_passed; |
| |
| if(duringconnect && data->set.connecttimeout) |
| timeout_ms = data->set.connecttimeout; |
| |
| if(data->set.timeout) { |
| /* get the strictest timeout of the ones converted to milliseconds */ |
| if(data->set.timeout < timeout_ms) |
| timeout_ms = data->set.timeout; |
| } |
| |
| /* Evaluate in milliseconds how much time that has passed */ |
| has_passed = Curl_tvdiff(Curl_tvnow(), data->progress.t_startsingle); |
| |
| /* subtract the passed time */ |
| timeout_ms -= has_passed; |
| |
| if(timeout_ms < 0) { |
| /* a precaution, no need to continue if time already is up */ |
| failf(data, "SSL connection timeout"); |
| return CURLE_OPERATION_TIMEOUTED; |
| } |
| |
| rc = Curl_socket_ready(conn->sock[sockindex], |
| conn->sock[sockindex], (int)timeout_ms); |
| if(rc > 0) |
| /* reabable or writable, go loop*/ |
| continue; |
| else if(0 == rc) { |
| /* timeout */ |
| failf(data, "SSL connection timeout"); |
| return CURLE_OPERATION_TIMEDOUT; |
| } |
| else { |
| /* anything that gets here is fatally bad */ |
| failf(data, "select/poll on SSL socket, errno: %d", SOCKERRNO); |
| return CURLE_SSL_CONNECT_ERROR; |
| } |
| } |
| else |
| break; |
| } while(1); |
| |
| if (rc < 0) { |
| failf(data, "gnutls_handshake() failed: %s", gnutls_strerror(rc)); |
| return CURLE_SSL_CONNECT_ERROR; |
| } |
| |
| return CURLE_OK; |
| } |
| |
| static gnutls_x509_crt_fmt do_file_type(const char *type) |
| { |
| if(!type || !type[0]) |
| return GNUTLS_X509_FMT_PEM; |
| if(curl_strequal(type, "PEM")) |
| return GNUTLS_X509_FMT_PEM; |
| if(curl_strequal(type, "DER")) |
| return GNUTLS_X509_FMT_DER; |
| return -1; |
| } |
| |
| |
| /* |
| * This function is called after the TCP connect has completed. Setup the TLS |
| * layer and do all necessary magic. |
| */ |
| CURLcode |
| Curl_gtls_connect(struct connectdata *conn, |
| int sockindex) |
| |
| { |
| const int cert_type_priority[] = { GNUTLS_CRT_X509, 0 }; |
| struct SessionHandle *data = conn->data; |
| gnutls_session session; |
| int rc; |
| unsigned int cert_list_size; |
| const gnutls_datum *chainp; |
| unsigned int verify_status; |
| gnutls_x509_crt x509_cert; |
| char certbuf[256]; /* big enough? */ |
| size_t size; |
| unsigned int algo; |
| unsigned int bits; |
| time_t clock; |
| const char *ptr; |
| void *ssl_sessionid; |
| size_t ssl_idsize; |
| |
| if (!gtls_inited) _Curl_gtls_init(); |
| /* GnuTLS only supports TLSv1 (and SSLv3?) */ |
| if(data->set.ssl.version == CURL_SSLVERSION_SSLv2) { |
| failf(data, "GnuTLS does not support SSLv2"); |
| return CURLE_SSL_CONNECT_ERROR; |
| } |
| |
| /* allocate a cred struct */ |
| rc = gnutls_certificate_allocate_credentials(&conn->ssl[sockindex].cred); |
| if(rc < 0) { |
| failf(data, "gnutls_cert_all_cred() failed: %s", gnutls_strerror(rc)); |
| return CURLE_SSL_CONNECT_ERROR; |
| } |
| |
| if(data->set.ssl.CAfile) { |
| /* set the trusted CA cert bundle file */ |
| gnutls_certificate_set_verify_flags(conn->ssl[sockindex].cred, |
| GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT); |
| |
| rc = gnutls_certificate_set_x509_trust_file(conn->ssl[sockindex].cred, |
| data->set.ssl.CAfile, |
| GNUTLS_X509_FMT_PEM); |
| if(rc < 0) { |
| infof(data, "error reading ca cert file %s (%s)\n", |
| data->set.ssl.CAfile, gnutls_strerror(rc)); |
| if (data->set.ssl.verifypeer) |
| return CURLE_SSL_CACERT_BADFILE; |
| } |
| else |
| infof(data, "found %d certificates in %s\n", |
| rc, data->set.ssl.CAfile); |
| } |
| |
| /* Initialize TLS session as a client */ |
| rc = gnutls_init(&conn->ssl[sockindex].session, GNUTLS_CLIENT); |
| if(rc) { |
| failf(data, "gnutls_init() failed: %d", rc); |
| return CURLE_SSL_CONNECT_ERROR; |
| } |
| |
| /* convenient assign */ |
| session = conn->ssl[sockindex].session; |
| |
| /* Use default priorities */ |
| rc = gnutls_set_default_priority(session); |
| if(rc < 0) |
| return CURLE_SSL_CONNECT_ERROR; |
| |
| /* Sets the priority on the certificate types supported by gnutls. Priority |
| is higher for types specified before others. After specifying the types |
| you want, you must append a 0. */ |
| rc = gnutls_certificate_type_set_priority(session, cert_type_priority); |
| if(rc < 0) |
| return CURLE_SSL_CONNECT_ERROR; |
| |
| if(data->set.cert) { |
| if( gnutls_certificate_set_x509_key_file( |
| conn->ssl[sockindex].cred, data->set.cert, |
| data->set.key != 0 ? data->set.key : data->set.cert, |
| do_file_type(data->set.cert_type) ) ) { |
| failf(data, "error reading X.509 key or certificate file"); |
| return CURLE_SSL_CONNECT_ERROR; |
| } |
| } |
| |
| /* put the credentials to the current session */ |
| rc = gnutls_credentials_set(session, GNUTLS_CRD_CERTIFICATE, |
| conn->ssl[sockindex].cred); |
| |
| /* set the connection handle (file descriptor for the socket) */ |
| gnutls_transport_set_ptr(session, |
| (gnutls_transport_ptr)conn->sock[sockindex]); |
| |
| /* register callback functions to send and receive data. */ |
| gnutls_transport_set_push_function(session, Curl_gtls_push); |
| gnutls_transport_set_pull_function(session, Curl_gtls_pull); |
| |
| /* lowat must be set to zero when using custom push and pull functions. */ |
| gnutls_transport_set_lowat(session, 0); |
| |
| /* This might be a reconnect, so we check for a session ID in the cache |
| to speed up things */ |
| |
| if(!Curl_ssl_getsessionid(conn, &ssl_sessionid, &ssl_idsize)) { |
| /* we got a session id, use it! */ |
| gnutls_session_set_data(session, ssl_sessionid, ssl_idsize); |
| |
| /* Informational message */ |
| infof (data, "SSL re-using session ID\n"); |
| } |
| |
| rc = handshake(conn, session, sockindex, TRUE); |
| if(rc) |
| /* handshake() sets its own error message with failf() */ |
| return rc; |
| |
| /* This function will return the peer's raw certificate (chain) as sent by |
| the peer. These certificates are in raw format (DER encoded for |
| X.509). In case of a X.509 then a certificate list may be present. The |
| first certificate in the list is the peer's certificate, following the |
| issuer's certificate, then the issuer's issuer etc. */ |
| |
| chainp = gnutls_certificate_get_peers(session, &cert_list_size); |
| if(!chainp) { |
| if(data->set.ssl.verifyhost) { |
| failf(data, "failed to get server cert"); |
| return CURLE_SSL_PEER_CERTIFICATE; |
| } |
| infof(data, "\t common name: WARNING couldn't obtain\n"); |
| } |
| |
| /* This function will try to verify the peer's certificate and return its |
| status (trusted, invalid etc.). The value of status should be one or more |
| of the gnutls_certificate_status_t enumerated elements bitwise or'd. To |
| avoid denial of service attacks some default upper limits regarding the |
| certificate key size and chain size are set. To override them use |
| gnutls_certificate_set_verify_limits(). */ |
| |
| rc = gnutls_certificate_verify_peers2(session, &verify_status); |
| if (rc < 0) { |
| failf(data, "server cert verify failed: %d", rc); |
| return CURLE_SSL_CONNECT_ERROR; |
| } |
| |
| /* verify_status is a bitmask of gnutls_certificate_status bits */ |
| if(verify_status & GNUTLS_CERT_INVALID) { |
| if (data->set.ssl.verifypeer) { |
| failf(data, "server certificate verification failed. CAfile: %s", |
| data->set.ssl.CAfile?data->set.ssl.CAfile:"none"); |
| return CURLE_SSL_CACERT; |
| } |
| else |
| infof(data, "\t server certificate verification FAILED\n"); |
| } |
| else |
| infof(data, "\t server certificate verification OK\n"); |
| |
| /* initialize an X.509 certificate structure. */ |
| gnutls_x509_crt_init(&x509_cert); |
| |
| /* convert the given DER or PEM encoded Certificate to the native |
| gnutls_x509_crt_t format */ |
| gnutls_x509_crt_import(x509_cert, chainp, GNUTLS_X509_FMT_DER); |
| |
| size=sizeof(certbuf); |
| rc = gnutls_x509_crt_get_dn_by_oid(x509_cert, GNUTLS_OID_X520_COMMON_NAME, |
| 0, /* the first and only one */ |
| FALSE, |
| certbuf, |
| &size); |
| if(rc) { |
| infof(data, "error fetching CN from cert:%s\n", |
| gnutls_strerror(rc)); |
| } |
| |
| /* This function will check if the given certificate's subject matches the |
| given hostname. This is a basic implementation of the matching described |
| in RFC2818 (HTTPS), which takes into account wildcards, and the subject |
| alternative name PKIX extension. Returns non zero on success, and zero on |
| failure. */ |
| rc = gnutls_x509_crt_check_hostname(x509_cert, conn->host.name); |
| |
| if(!rc) { |
| if (data->set.ssl.verifyhost > 1) { |
| failf(data, "SSL: certificate subject name (%s) does not match " |
| "target host name '%s'", certbuf, conn->host.dispname); |
| gnutls_x509_crt_deinit(x509_cert); |
| return CURLE_SSL_PEER_CERTIFICATE; |
| } |
| else |
| infof(data, "\t common name: %s (does not match '%s')\n", |
| certbuf, conn->host.dispname); |
| } |
| else |
| infof(data, "\t common name: %s (matched)\n", certbuf); |
| |
| /* Show: |
| |
| - ciphers used |
| - subject |
| - start date |
| - expire date |
| - common name |
| - issuer |
| |
| */ |
| |
| /* public key algorithm's parameters */ |
| algo = gnutls_x509_crt_get_pk_algorithm(x509_cert, &bits); |
| infof(data, "\t certificate public key: %s\n", |
| gnutls_pk_algorithm_get_name(algo)); |
| |
| /* version of the X.509 certificate. */ |
| infof(data, "\t certificate version: #%d\n", |
| gnutls_x509_crt_get_version(x509_cert)); |
| |
| |
| size = sizeof(certbuf); |
| gnutls_x509_crt_get_dn(x509_cert, certbuf, &size); |
| infof(data, "\t subject: %s\n", certbuf); |
| |
| clock = gnutls_x509_crt_get_activation_time(x509_cert); |
| showtime(data, "start date", clock); |
| |
| clock = gnutls_x509_crt_get_expiration_time(x509_cert); |
| showtime(data, "expire date", clock); |
| |
| size = sizeof(certbuf); |
| gnutls_x509_crt_get_issuer_dn(x509_cert, certbuf, &size); |
| infof(data, "\t issuer: %s\n", certbuf); |
| |
| gnutls_x509_crt_deinit(x509_cert); |
| |
| /* compression algorithm (if any) */ |
| ptr = gnutls_compression_get_name(gnutls_compression_get(session)); |
| /* the *_get_name() says "NULL" if GNUTLS_COMP_NULL is returned */ |
| infof(data, "\t compression: %s\n", ptr); |
| |
| /* the name of the cipher used. ie 3DES. */ |
| ptr = gnutls_cipher_get_name(gnutls_cipher_get(session)); |
| infof(data, "\t cipher: %s\n", ptr); |
| |
| /* the MAC algorithms name. ie SHA1 */ |
| ptr = gnutls_mac_get_name(gnutls_mac_get(session)); |
| infof(data, "\t MAC: %s\n", ptr); |
| |
| if(!ssl_sessionid) { |
| /* this session was not previously in the cache, add it now */ |
| |
| /* get the session ID data size */ |
| gnutls_session_get_data(session, NULL, &ssl_idsize); |
| ssl_sessionid = malloc(ssl_idsize); /* get a buffer for it */ |
| |
| if(ssl_sessionid) { |
| /* extract session ID to the allocated buffer */ |
| gnutls_session_get_data(session, ssl_sessionid, &ssl_idsize); |
| |
| /* store this session id */ |
| return Curl_ssl_addsessionid(conn, ssl_sessionid, ssl_idsize); |
| } |
| } |
| |
| return CURLE_OK; |
| } |
| |
| |
| /* return number of sent (non-SSL) bytes */ |
| ssize_t Curl_gtls_send(struct connectdata *conn, |
| int sockindex, |
| void *mem, |
| size_t len) |
| { |
| ssize_t rc = gnutls_record_send(conn->ssl[sockindex].session, mem, len); |
| |
| if(rc < 0 ) { |
| if(rc == GNUTLS_E_AGAIN) |
| return 0; /* EWOULDBLOCK equivalent */ |
| rc = -1; /* generic error code for send failure */ |
| } |
| |
| return rc; |
| } |
| |
| void Curl_gtls_close_all(struct SessionHandle *data) |
| { |
| /* FIX: make the OpenSSL code more generic and use parts of it here */ |
| (void)data; |
| } |
| |
| static void close_one(struct connectdata *conn, |
| int index) |
| { |
| if(conn->ssl[index].session) { |
| gnutls_bye(conn->ssl[index].session, GNUTLS_SHUT_RDWR); |
| gnutls_deinit(conn->ssl[index].session); |
| } |
| if(conn->ssl[index].cred) |
| gnutls_certificate_free_credentials(conn->ssl[index].cred); |
| } |
| |
| void Curl_gtls_close(struct connectdata *conn) |
| { |
| if(conn->ssl[0].use) |
| close_one(conn, 0); |
| if(conn->ssl[1].use) |
| close_one(conn, 1); |
| } |
| |
| /* |
| * This function is called to shut down the SSL layer but keep the |
| * socket open (CCC - Clear Command Channel) |
| */ |
| int Curl_gtls_shutdown(struct connectdata *conn, int sockindex) |
| { |
| int result; |
| int retval = 0; |
| struct SessionHandle *data = conn->data; |
| int done = 0; |
| char buf[120]; |
| |
| /* This has only been tested on the proftpd server, and the mod_tls code |
| sends a close notify alert without waiting for a close notify alert in |
| response. Thus we wait for a close notify alert from the server, but |
| we do not send one. Let's hope other servers do the same... */ |
| |
| if(data->set.ftp_ccc == CURLFTPSSL_CCC_ACTIVE) |
| gnutls_bye(conn->ssl[sockindex].session, GNUTLS_SHUT_WR); |
| |
| if(conn->ssl[sockindex].session) { |
| while(!done) { |
| int what = Curl_socket_ready(conn->sock[sockindex], |
| CURL_SOCKET_BAD, SSL_SHUTDOWN_TIMEOUT); |
| if(what > 0) { |
| /* Something to read, let's do it and hope that it is the close |
| notify alert from the server */ |
| result = gnutls_record_recv(conn->ssl[sockindex].session, |
| buf, sizeof(buf)); |
| switch(result) { |
| case 0: |
| /* This is the expected response. There was no data but only |
| the close notify alert */ |
| done = 1; |
| break; |
| case GNUTLS_E_AGAIN: |
| case GNUTLS_E_INTERRUPTED: |
| infof(data, "GNUTLS_E_AGAIN || GNUTLS_E_INTERRUPTED\n"); |
| break; |
| default: |
| retval = -1; |
| done = 1; |
| break; |
| } |
| } |
| else if(0 == what) { |
| /* timeout */ |
| failf(data, "SSL shutdown timeout"); |
| done = 1; |
| break; |
| } |
| else { |
| /* anything that gets here is fatally bad */ |
| failf(data, "select/poll on SSL socket, errno: %d", SOCKERRNO); |
| retval = -1; |
| done = 1; |
| } |
| } |
| gnutls_deinit(conn->ssl[sockindex].session); |
| } |
| gnutls_certificate_free_credentials(conn->ssl[sockindex].cred); |
| |
| conn->ssl[sockindex].session = NULL; |
| conn->ssl[sockindex].use = FALSE; |
| |
| return retval; |
| } |
| |
| /* |
| * If the read would block we return -1 and set 'wouldblock' to TRUE. |
| * Otherwise we return the amount of data read. Other errors should return -1 |
| * and set 'wouldblock' to FALSE. |
| */ |
| ssize_t Curl_gtls_recv(struct connectdata *conn, /* connection data */ |
| int num, /* socketindex */ |
| char *buf, /* store read data here */ |
| size_t buffersize, /* max amount to read */ |
| bool *wouldblock) |
| { |
| ssize_t ret; |
| |
| ret = gnutls_record_recv(conn->ssl[num].session, buf, buffersize); |
| if((ret == GNUTLS_E_AGAIN) || (ret == GNUTLS_E_INTERRUPTED)) { |
| *wouldblock = TRUE; |
| return -1; |
| } |
| |
| if(ret == GNUTLS_E_REHANDSHAKE) { |
| /* BLOCKING call, this is bad but a work-around for now. Fixing this "the |
| proper way" takes a whole lot of work. */ |
| CURLcode rc = handshake(conn, conn->ssl[num].session, num, FALSE); |
| if(rc) |
| /* handshake() writes error message on its own */ |
| return rc; |
| *wouldblock = TRUE; /* then return as if this was a wouldblock */ |
| return -1; |
| } |
| |
| *wouldblock = FALSE; |
| if (!ret) { |
| failf(conn->data, "Peer closed the TLS connection"); |
| return -1; |
| } |
| |
| if (ret < 0) { |
| failf(conn->data, "GnuTLS recv error (%d): %s", |
| (int)ret, gnutls_strerror(ret)); |
| return -1; |
| } |
| |
| return ret; |
| } |
| |
| void Curl_gtls_session_free(void *ptr) |
| { |
| free(ptr); |
| } |
| |
| size_t Curl_gtls_version(char *buffer, size_t size) |
| { |
| return snprintf(buffer, size, " GnuTLS/%s", gnutls_check_version(NULL)); |
| } |
| |
| #endif /* USE_GNUTLS */ |