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Diffstat (limited to 'Utilities/cmcurl/gtls.c')
| -rw-r--r-- | Utilities/cmcurl/gtls.c | 640 |
1 files changed, 640 insertions, 0 deletions
diff --git a/Utilities/cmcurl/gtls.c b/Utilities/cmcurl/gtls.c new file mode 100644 index 000000000..250ecada4 --- /dev/null +++ b/Utilities/cmcurl/gtls.c @@ -0,0 +1,640 @@ +/*************************************************************************** + * _ _ ____ _ + * 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_TYPES_H +#include <sys/types.h> +#endif +#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 + +/* + * 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) +{ + gnutls_global_init(); +#ifdef GTLSDEBUG + gnutls_global_set_log_function(tls_log_func); + gnutls_global_set_log_level(2); +#endif + return 1; +} + +int Curl_gtls_cleanup(void) +{ + 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; + + 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*1000; + + if(data->set.timeout) { + /* get the strictest timeout of the ones converted to milliseconds */ + if((data->set.timeout*1000) < timeout_ms) + timeout_ms = data->set.timeout*1000; + } + + /* 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_select(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 on SSL socket, errno: %d", Curl_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; + + /* 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); + } + 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; + ssize_t nread; + 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(conn->ssl[sockindex].session) { + while(!done) { + int what = Curl_select(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 on SSL socket, errno: %d", Curl_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 */ |