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gnutls.c
1403 lines (1227 loc) · 38 KB
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gnutls.c
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/*
* OpenConnect (SSL + DTLS) VPN client
*
* Copyright © 2008-2012 Intel Corporation.
*
* Author: David Woodhouse <dwmw2@infradead.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* version 2.1, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to:
*
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301 USA
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <netdb.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <ctype.h>
#include <stdio.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#include <stdarg.h>
#include <stdlib.h>
#include <gnutls/gnutls.h>
#include <gnutls/x509.h>
#include <gnutls/crypto.h>
#include <gnutls/pkcs12.h>
#include <gnutls/abstract.h>
#ifdef HAVE_P11KIT
#include <p11-kit/p11-kit.h>
#include <p11-kit/pkcs11.h>
#include <p11-kit/pin.h>
static P11KitPin *pin_callback(const char *pin_source, P11KitUri *pin_uri,
const char *pin_description,
P11KitPinFlags flags,
void *_vpninfo);
#if GNUTLS_VERSION_MAJOR >= 3
#define HAVE_P11KIT_AND_GNUTLS_3
#endif
#endif
#include "openconnect-internal.h"
/* Helper functions for reading/writing lines over SSL.
We could use cURL for the HTTP stuff, but it's overkill */
int openconnect_SSL_write(struct openconnect_info *vpninfo, char *buf, size_t len)
{
size_t orig_len = len;
while (len) {
int done = gnutls_record_send(vpninfo->https_sess, buf, len);
if (done > 0)
len -= done;
else if (done != GNUTLS_E_AGAIN) {
vpn_progress(vpninfo, PRG_ERR, _("Failed to write to SSL socket: %s"),
gnutls_strerror(done));
return -EIO;
} else {
fd_set wr_set, rd_set;
int maxfd = vpninfo->ssl_fd;
FD_ZERO(&wr_set);
FD_ZERO(&rd_set);
if (gnutls_record_get_direction(vpninfo->https_sess))
FD_SET(vpninfo->ssl_fd, &wr_set);
else
FD_SET(vpninfo->ssl_fd, &rd_set);
if (vpninfo->cancel_fd != -1) {
FD_SET(vpninfo->cancel_fd, &rd_set);
if (vpninfo->cancel_fd > vpninfo->ssl_fd)
maxfd = vpninfo->cancel_fd;
}
select(maxfd + 1, &rd_set, &wr_set, NULL, NULL);
if (vpninfo->cancel_fd != -1 &&
FD_ISSET(vpninfo->cancel_fd, &rd_set)) {
vpn_progress(vpninfo, PRG_ERR, _("SSL write cancelled\n"));
return -EINTR;
}
}
}
return orig_len;
}
int openconnect_SSL_read(struct openconnect_info *vpninfo, char *buf, size_t len)
{
int done;
while ((done = gnutls_record_recv(vpninfo->https_sess, buf, len)) < 0) {
fd_set wr_set, rd_set;
int maxfd = vpninfo->ssl_fd;
if (done != GNUTLS_E_AGAIN) {
vpn_progress(vpninfo, PRG_ERR, _("Failed to read from SSL socket: %s"),
gnutls_strerror(done));
return -EIO;
} else {
FD_ZERO(&wr_set);
FD_ZERO(&rd_set);
if (gnutls_record_get_direction(vpninfo->https_sess))
FD_SET(vpninfo->ssl_fd, &wr_set);
else
FD_SET(vpninfo->ssl_fd, &rd_set);
if (vpninfo->cancel_fd != -1) {
FD_SET(vpninfo->cancel_fd, &rd_set);
if (vpninfo->cancel_fd > vpninfo->ssl_fd)
maxfd = vpninfo->cancel_fd;
}
select(maxfd + 1, &rd_set, &wr_set, NULL, NULL);
if (vpninfo->cancel_fd != -1 &&
FD_ISSET(vpninfo->cancel_fd, &rd_set)) {
vpn_progress(vpninfo, PRG_ERR, _("SSL read cancelled\n"));
return -EINTR;
}
}
}
return done;
}
int openconnect_SSL_gets(struct openconnect_info *vpninfo, char *buf, size_t len)
{
int i = 0;
int ret;
if (len < 2)
return -EINVAL;
while (1) {
ret = gnutls_record_recv(vpninfo->https_sess, buf + i, 1);
if (ret == 1) {
if (buf[i] == '\n') {
buf[i] = 0;
if (i && buf[i-1] == '\r') {
buf[i-1] = 0;
i--;
}
return i;
}
i++;
if (i >= len - 1) {
buf[i] = 0;
return i;
}
} else if (ret != GNUTLS_E_AGAIN) {
vpn_progress(vpninfo, PRG_ERR, _("Failed to read from SSL socket: %s\n"),
gnutls_strerror(ret));
ret = -EIO;
break;
} else {
fd_set rd_set, wr_set;
int maxfd = vpninfo->ssl_fd;
FD_ZERO(&rd_set);
FD_ZERO(&wr_set);
if (gnutls_record_get_direction(vpninfo->https_sess))
FD_SET(vpninfo->ssl_fd, &wr_set);
else
FD_SET(vpninfo->ssl_fd, &rd_set);
if (vpninfo->cancel_fd != -1) {
FD_SET(vpninfo->cancel_fd, &rd_set);
if (vpninfo->cancel_fd > vpninfo->ssl_fd)
maxfd = vpninfo->cancel_fd;
}
select(maxfd + 1, &rd_set, &wr_set, NULL, NULL);
if (vpninfo->cancel_fd != -1 &&
FD_ISSET(vpninfo->cancel_fd, &rd_set)) {
vpn_progress(vpninfo, PRG_ERR, _("SSL read cancelled\n"));
ret = -EINTR;
break;
}
}
}
buf[i] = 0;
return i ?: ret;
}
static int check_certificate_expiry(struct openconnect_info *vpninfo, gnutls_x509_crt_t cert)
{
const char *reason = NULL;
time_t expires = gnutls_x509_crt_get_expiration_time(cert);
time_t now = time(NULL);
if (expires == -1) {
vpn_progress(vpninfo, PRG_ERR,
_("Could not extract expiration time of certificate\n"));
return -EINVAL;
}
if (expires < now)
reason = _("Client certificate has expired at");
else if (expires < now + vpninfo->cert_expire_warning)
reason = _("Client certificate expires soon at");
if (reason) {
struct tm tm;
char buf[80];
gmtime_r(&expires, &tm);
strftime(buf, 80, "%a, %d %b %Y %T %Z", &tm);
vpn_progress(vpninfo, PRG_ERR, "%s: %s\n", reason, buf);
}
return 0;
}
/* For systems that don't support O_CLOEXEC, just don't bother.
It's not open for long anyway. */
#ifndef O_CLOEXEC
#define O_CLOEXEC
#endif
static int load_datum(struct openconnect_info *vpninfo,
gnutls_datum_t *datum, const char *fname)
{
struct stat st;
int fd, err;
fd = open(fname, O_RDONLY|O_CLOEXEC);
if (fd == -1) {
err = errno;
vpn_progress(vpninfo, PRG_ERR,
_("Failed to open key/certificate file %s: %s\n"),
fname, strerror(err));
return -ENOENT;
}
if (fstat(fd, &st)) {
err = errno;
vpn_progress(vpninfo, PRG_ERR,
_("Failed to stat key/certificate file %s: %s\n"),
fname, strerror(err));
close(fd);
return -EIO;
}
datum->size = st.st_size;
datum->data = gnutls_malloc(st.st_size + 1);
if (!datum->data) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to allocate certificate buffer\n"));
close(fd);
return -ENOMEM;
}
errno = EAGAIN;
if (read(fd, datum->data, datum->size) != datum->size) {
err = errno;
vpn_progress(vpninfo, PRG_ERR,
_("Failed to read certificate into memory: %s\n"),
strerror(err));
close(fd);
gnutls_free(datum->data);
return -EIO;
}
datum->data[st.st_size] = 0;
close(fd);
return 0;
}
#ifndef HAVE_GNUTLS_PKCS12_SIMPLE_PARSE
/* If we're using a version of GnuTLS from before this was
exported, pull in our local copy. */
#include "gnutls_pkcs12.c"
#endif
/* A non-zero, non-error return to make load_certificate() continue and
interpreting the file as other types */
#define NOT_PKCS12 1
static int load_pkcs12_certificate(struct openconnect_info *vpninfo,
gnutls_datum_t *datum,
gnutls_x509_privkey_t *key,
gnutls_x509_crt_t **chain,
unsigned int *chain_len,
gnutls_x509_crt_t **extra_certs,
unsigned int *extra_certs_len,
gnutls_x509_crl_t *crl)
{
gnutls_pkcs12_t p12;
char *pass;
int err;
err = gnutls_pkcs12_init(&p12);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to setup PKCS#12 data structure: %s\n"),
gnutls_strerror(err));
return -EIO;
}
err = gnutls_pkcs12_import(p12, datum, GNUTLS_X509_FMT_DER, 0);
if (err) {
gnutls_pkcs12_deinit(p12);
if (vpninfo->cert_type == CERT_TYPE_UNKNOWN)
return NOT_PKCS12;
vpn_progress(vpninfo, PRG_ERR,
_("Failed to import PKCS#12 file: %s\n"),
gnutls_strerror(err));
return -EINVAL;
}
pass = vpninfo->cert_password;
while ((err = gnutls_pkcs12_verify_mac(p12, pass)) == GNUTLS_E_MAC_VERIFY_FAILED) {
if (pass)
vpn_progress(vpninfo, PRG_ERR,
_("Failed to decrypt PKCS#12 certificate file\n"));
free(pass);
vpninfo->cert_password = NULL;
err = request_passphrase(vpninfo, &pass,
_("Enter PKCS#12 pass phrase:"));
if (err) {
gnutls_pkcs12_deinit(p12);
return -EINVAL;
}
}
/* If it wasn't GNUTLS_E_MAC_VERIFY_FAILED, then the problem wasn't just a
bad password. Give up. */
if (err) {
int level = PRG_ERR;
int ret = -EINVAL;
gnutls_pkcs12_deinit(p12);
/* If the first attempt, and we didn't know for sure it was PKCS#12
anyway, bail out and try loading it as something different. */
if (pass == vpninfo->cert_password &&
vpninfo->cert_type == CERT_TYPE_UNKNOWN) {
/* Make it non-fatal... */
level = PRG_TRACE;
ret = NOT_PKCS12;
}
vpn_progress(vpninfo, level,
_("Failed to process PKCS#12 file: %s\n"),
gnutls_strerror(err));
return ret;
}
err = gnutls_pkcs12_simple_parse(p12, pass, key, chain, chain_len,
extra_certs, extra_certs_len, crl, 0);
free(pass);
vpninfo->cert_password = NULL;
gnutls_pkcs12_deinit(p12);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to load PKCS#12 certificate: %s\n"),
gnutls_strerror(err));
return -EINVAL;
}
return 0;
}
/* Older versions of GnuTLS didn't actually bother to check this, so we'll
do it for them. */
static int check_issuer_sanity(gnutls_x509_crt_t cert, gnutls_x509_crt_t issuer)
{
#if GNUTLS_VERSION_NUMBER > 0x300014
return 0;
#else
unsigned char id1[512], id2[512];
size_t id1_size = 512, id2_size = 512;
int err;
err = gnutls_x509_crt_get_authority_key_id(cert, id1, &id1_size, NULL);
if (err)
return 0;
err = gnutls_x509_crt_get_subject_key_id(issuer, id2, &id2_size, NULL);
if (err)
return 0;
if (id1_size == id2_size && !memcmp(id1, id2, id1_size))
return 0;
/* EEP! */
return -EIO;
#endif
}
static int count_x509_certificates(gnutls_datum_t *datum)
{
int count = 0;
char *p = (char *)datum->data;
while (p) {
p = strstr(p, "-----BEGIN ");
if (!p)
break;
p += 11;
if (!strncmp(p, "CERTIFICATE", 11) ||
!strncmp(p, "X509 CERTIFICATE", 16))
count++;
}
return count;
}
static int get_cert_name(gnutls_x509_crt_t cert, char *name, size_t namelen)
{
if (gnutls_x509_crt_get_dn_by_oid(cert, GNUTLS_OID_X520_COMMON_NAME,
0, 0, name, &namelen) &&
gnutls_x509_crt_get_dn(cert, name, &namelen)) {
name[namelen-1] = 0;
snprintf(name, namelen-1, "<unknown>");
return -EINVAL;
}
return 0;
}
static int load_certificate(struct openconnect_info *vpninfo)
{
gnutls_datum_t fdata;
gnutls_x509_privkey_t key = NULL;
#ifdef HAVE_P11KIT
gnutls_privkey_t pkey = NULL;
char *cert_url = (char *)vpninfo->cert;
char *key_url = (char *)vpninfo->sslkey;
#endif
gnutls_x509_crl_t crl = NULL;
gnutls_x509_crt_t last_cert, cert = NULL;
gnutls_x509_crt_t *extra_certs = NULL, *supporting_certs = NULL;
unsigned int nr_supporting_certs = 0, nr_extra_certs = 0;
unsigned int certs_to_free = 0; /* How many of supporting_certs */
int err; /* GnuTLS error */
int ret = 0; /* our error (zero or -errno) */
int i;
int cert_is_p11 = 0, key_is_p11 = 0;
unsigned char key_id[20];
size_t key_id_size = sizeof(key_id);
char name[80];
fdata.data = NULL;
if (vpninfo->cert_type == CERT_TYPE_TPM) {
vpn_progress(vpninfo, PRG_ERR,
_("TPM support not available with GnuTLS\n"));
return -EINVAL;
}
key_is_p11 = !strncmp(vpninfo->sslkey, "pkcs11:", 7);
cert_is_p11 = !strncmp(vpninfo->cert, "pkcs11:", 7);
/* Install PIN handler if either certificate or key are coming from PKCS#11 */
if (key_is_p11 || cert_is_p11) {
#ifdef HAVE_P11KIT
CK_OBJECT_CLASS class;
CK_ATTRIBUTE attr;
char pin_source[40];
P11KitUri *uri;
sprintf(pin_source, "openconnect:%p", vpninfo);
p11_kit_pin_register_callback(pin_source, pin_callback, vpninfo, NULL);
uri = p11_kit_uri_new();
attr.type = CKA_CLASS;
attr.pValue = &class;
attr.ulValueLen = sizeof(class);
/* Add appropriate pin-source and object-type attributes to
both certificate and key URLs, unless they already exist. */
if (cert_is_p11 &&
!p11_kit_uri_parse(cert_url, P11_KIT_URI_FOR_OBJECT, uri)) {
if (!p11_kit_uri_get_pin_source(uri))
p11_kit_uri_set_pin_source(uri, pin_source);
if (!p11_kit_uri_get_attribute(uri, CKA_CLASS)) {
class = CKO_CERTIFICATE;
p11_kit_uri_set_attribute(uri, &attr);
}
p11_kit_uri_format(uri, P11_KIT_URI_FOR_OBJECT, &cert_url);
}
if (key_is_p11 &&
!p11_kit_uri_parse(key_url, P11_KIT_URI_FOR_OBJECT, uri)) {
if (!p11_kit_uri_get_pin_source(uri))
p11_kit_uri_set_pin_source(uri, pin_source);
if (!p11_kit_uri_get_attribute(uri, CKA_CLASS)) {
class = CKO_PRIVATE_KEY;
p11_kit_uri_set_attribute(uri, &attr);
}
p11_kit_uri_format(uri, P11_KIT_URI_FOR_OBJECT, &key_url);
}
p11_kit_uri_free(uri);
#else
vpn_progress(vpninfo, PRG_ERR,
_("This binary built without PKCS#11 support\n"));
return -EINVAL;
#endif
}
/* Load certificate(s) first... */
#ifdef HAVE_P11KIT
#ifndef HAVE_P11KIT_AND_GNUTLS_3
if (key_is_p11) {
/* With GnuTLS 2.12 we can't *see* the key so we can't
do the expiry check or fill in intermediate CAs. */
err = gnutls_certificate_set_x509_key_file(vpninfo->https_cred,
cert_url, key_url,
GNUTLS_X509_FMT_PEM);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Error loading PKCS#11 certificate: %s\n"),
gnutls_strerror(err));
ret = -EIO;
goto out;
}
ret = 0;
goto out;
}
#endif
if (cert_is_p11) {
vpn_progress(vpninfo, PRG_TRACE,
_("Using PKCS#11 certificate %s\n"), cert_url);
err = gnutls_x509_crt_init(&cert);
if (err) {
ret = -ENOMEM;
goto out;
}
err = gnutls_x509_crt_import_pkcs11_url(cert, cert_url, 0);
if (err == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE)
err = gnutls_x509_crt_import_pkcs11_url(cert, cert_url,
GNUTLS_PKCS11_OBJ_FLAG_LOGIN);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Error loading certificate from PKCS#11: %s\n"),
gnutls_strerror(err));
ret = -EIO;
goto out;
}
goto got_certs;
}
#endif
vpn_progress(vpninfo, PRG_TRACE,
_("Using certificate file %s\n"), vpninfo->cert);
ret = load_datum(vpninfo, &fdata, vpninfo->cert);
if (ret)
return ret;
if (!key_is_p11 && (vpninfo->cert_type == CERT_TYPE_PKCS12 ||
vpninfo->cert_type == CERT_TYPE_UNKNOWN)) {
/* PKCS#12 should actually contain certificates *and* private key */
ret = load_pkcs12_certificate(vpninfo, &fdata, &key,
&supporting_certs, &nr_supporting_certs,
&extra_certs, &nr_extra_certs,
&crl);
if (ret < 0)
goto out;
else if (!ret) {
if (nr_supporting_certs) {
cert = supporting_certs[0];
goto got_key;
}
vpn_progress(vpninfo, PRG_ERR,
_("PKCS#11 file contained no certificate\n"));
ret = -EINVAL;
goto out;
}
/* It returned NOT_PKCS12.
Fall through to try PEM formats. */
}
/* We need to know how many there are in *advance*; it won't just allocate
the array for us :( */
nr_extra_certs = count_x509_certificates(&fdata);
if (!nr_extra_certs)
nr_extra_certs = 1; /* wtf? Oh well, we'll fail later... */
extra_certs = calloc(nr_extra_certs, sizeof(cert));
if (!extra_certs) {
nr_extra_certs = 0;
ret = -ENOMEM;
goto out;
}
err = gnutls_x509_crt_list_import(extra_certs, &nr_extra_certs, &fdata,
GNUTLS_X509_FMT_PEM, 0);
if (err <= 0) {
const char *reason;
if (!err || err == GNUTLS_E_NO_CERTIFICATE_FOUND)
reason = _("No certificate found in file");
else
reason = gnutls_strerror(err);
vpn_progress(vpninfo, PRG_ERR,
_("Loading certificate failed: %s\n"),
reason);
ret = -EINVAL;
goto out;
}
nr_extra_certs = err;
err = 0;
goto got_certs;
got_certs:
/* Now we have the certificate(s) and we're looking for the private key... */
#ifdef HAVE_P11KIT_AND_GNUTLS_3
if (key_is_p11) {
gnutls_pkcs11_privkey_t p11key = NULL;
vpn_progress(vpninfo, PRG_TRACE,
_("Using PKCS#11 key %s\n"), key_url);
err = gnutls_pkcs11_privkey_init(&p11key);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Error initialising PKCS#11 key structure: %s\n"),
gnutls_strerror(err));
ret = -EIO;
goto out;
}
err = gnutls_pkcs11_privkey_import_url(p11key, key_url, 0);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Error importing PKCS#11 URL %s: %s\n"),
key_url, gnutls_strerror(err));
gnutls_pkcs11_privkey_deinit(p11key);
ret = -EIO;
goto out;
}
err = gnutls_privkey_init(&pkey);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Error initialising private key structure: %s\n"),
gnutls_strerror(err));
gnutls_pkcs11_privkey_deinit(p11key);
ret = -EIO;
goto out;
}
err = gnutls_privkey_import_pkcs11(pkey, p11key, GNUTLS_PRIVKEY_IMPORT_AUTO_RELEASE);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Error importing PKCS#11 key into private key structure: %s\n"),
gnutls_strerror(err));
gnutls_pkcs11_privkey_deinit(p11key);
ret = -EIO;
goto out;
}
/* FIXME: How do we check which cert matches the pkey?
For now we just assume that the first one in the list is the right one. */
if (!cert) {
cert = extra_certs[0];
/* Move the rest of the array down */
for (i = 0; i < nr_extra_certs - 1; i++)
extra_certs[i] = extra_certs[i+1];
nr_extra_certs--;
}
goto got_key;
}
#endif
/* We're loading the private key from a file. Load the file into memory
unless it's the same as the certificate and we already loaded that. */
if (!fdata.data || vpninfo->sslkey != vpninfo->cert) {
gnutls_free(fdata.data);
fdata.data = NULL;
vpn_progress(vpninfo, PRG_TRACE,
_("Using private key file %s\n"), vpninfo->sslkey);
ret = load_datum(vpninfo, &fdata, vpninfo->sslkey);
if (ret)
goto out;
}
gnutls_x509_privkey_init(&key);
/* Try PKCS#1 (and PKCS#8 without password) first. GnuTLS doesn't
support OpenSSL's old PKCS#1-based encrypted format. We should
probably check for it and give a more coherent failure mode. */
err = gnutls_x509_privkey_import(key, &fdata, GNUTLS_X509_FMT_PEM);
if (err) {
/* If that fails, try PKCS#8 */
char *pass = vpninfo->cert_password;
/* Yay, just for fun this is *different* to PKCS#12. Where we could
try an empty password there, in this case the empty-password case
has already been *tried* by gnutls_x509_privkey_import(). If we
just call gnutls_x509_privkey_import_pkcs8() with a NULL password,
it'll SEGV. You have to set the GNUTLS_PKCS_PLAIN flag if you want
to try without a password. Passing NULL evidently isn't enough of
a hint. And in GnuTLS 3.1 where that crash has been fixed, passing
NULL will cause it to return GNUTLS_E_ENCRYPTED_STRUCTURE (a new
error code) rather than GNUTLS_E_DECRYPTION_FAILED. So just pass ""
instead of NULL, and don't worry about either case. */
while ((err = gnutls_x509_privkey_import_pkcs8(key, &fdata,
GNUTLS_X509_FMT_PEM,
pass?pass:"", 0))) {
if (err != GNUTLS_E_DECRYPTION_FAILED) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to load private key as PKCS#8: %s\n"),
gnutls_strerror(err));
ret = -EINVAL;
goto out;
}
vpninfo->cert_password = NULL;
if (pass) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to decrypt PKCS#8 certificate file\n"));
free(pass);
}
err = request_passphrase(vpninfo, &pass,
_("Enter PEM pass phrase:"));
if (err) {
ret = -EINVAL;
goto out;
}
}
free(pass);
vpninfo->cert_password = NULL;
}
/* Now attempt to make sure we use the *correct* certificate, to match the key */
err = gnutls_x509_privkey_get_key_id(key, 0, key_id, &key_id_size);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to get key ID: %s\n"),
gnutls_strerror(err));
goto out;
}
for (i = 0; i < (extra_certs?nr_extra_certs:1); i++) {
unsigned char cert_id[20];
size_t cert_id_size = sizeof(cert_id);
err = gnutls_x509_crt_get_key_id(extra_certs?extra_certs[i]:cert, 0, cert_id, &cert_id_size);
if (err)
continue;
if (cert_id_size == key_id_size && !memcmp(cert_id, key_id, key_id_size)) {
if (extra_certs) {
cert = extra_certs[i];
/* Move the rest of the array down */
for (; i < nr_extra_certs - 1; i++)
extra_certs[i] = extra_certs[i+1];
nr_extra_certs--;
}
goto got_key;
}
}
/* We shouldn't reach this. It means that we didn't find *any* matching cert */
vpn_progress(vpninfo, PRG_ERR,
_("No SSL certificate found to match private key\n"));
ret = -EINVAL;
goto out;
got_key:
/* Now we have both cert(s) and key, and we should be ready to go. */
check_certificate_expiry(vpninfo, cert);
get_cert_name(cert, name, sizeof(name));
vpn_progress(vpninfo, PRG_INFO, _("Using client certificate '%s'\n"),
name);
if (crl) {
err = gnutls_certificate_set_x509_crl(vpninfo->https_cred, &crl, 1);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Setting certificate recovation list failed: %s\n"),
gnutls_strerror(err));
goto out;
}
}
/* OpenSSL has problems with certificate chains — if there are
multiple certs with the same name, it doesn't necessarily
choose the _right_ one. (RT#1942)
Pick the right ones for ourselves and add them manually. */
if (nr_supporting_certs) {
/* We already got a bunch of certs from PKCS#12 file.
Remember how many need to be freed when we're done,
since we'll expand the supporting_certs array with
more from the cafile if we can. */
last_cert = supporting_certs[nr_supporting_certs-1];
certs_to_free = nr_supporting_certs;
} else {
last_cert = cert;
certs_to_free = nr_supporting_certs = 1;
}
while (1) {
gnutls_x509_crt_t issuer;
for (i = 0; i < nr_extra_certs; i++) {
if (gnutls_x509_crt_check_issuer(last_cert, extra_certs[i]) &&
!check_issuer_sanity(last_cert, extra_certs[i]))
break;
}
if (i < nr_extra_certs) {
issuer = extra_certs[i];
} else {
err = gnutls_certificate_get_issuer(vpninfo->https_cred,
last_cert, &issuer, 0);
if (err)
break;
}
/* The check_issuer_sanity() function works fine as a workaround where
it was used above, but when gnutls_certificate_get_issuer() returns
a bogus cert, there's nothing we can do to fix it up. We don't get
to iterate over all the available certs like we can over our own
list. */
if (check_issuer_sanity(last_cert, issuer)) {
/* Hm, is there a bug reference for this? Or just the git commit
reference (c1ef7efb in master, 5196786c in gnutls_3_0_x-2)? */
vpn_progress(vpninfo, PRG_ERR,
_("WARNING: GnuTLS returned incorrect issuer certs; authentication may fail!\n"));
break;
}
if (issuer == last_cert) {
/* Don't actually include the root CA. If they don't already trust it,
then handing it to them isn't going to help. But don't omit the
original certificate if it's self-signed. */
if (nr_supporting_certs > 1)
nr_supporting_certs--;
break;
}
/* OK, we found a new cert to add to our chain. */
supporting_certs = gnutls_realloc(supporting_certs,
sizeof(cert) * ++nr_supporting_certs);
if (!supporting_certs) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to allocate memory for supporting certificates\n"));
/* The world is probably about to end, but try without them anyway */
certs_to_free = 0;
ret = -ENOMEM;
goto out;
}
/* First time we actually allocated an array? Copy the first cert into it */
if (nr_supporting_certs == 2)
supporting_certs[0] = cert;
/* Append the new one */
supporting_certs[nr_supporting_certs-1] = issuer;
last_cert = issuer;
}
for (i = 1; i < nr_supporting_certs; i++) {
get_cert_name(supporting_certs[i], name, sizeof(name));
vpn_progress(vpninfo, PRG_DEBUG,
_("Adding supporting CA '%s'\n"), name);
}
#ifdef HAVE_P11KIT_AND_GNUTLS_3
if (pkey) {
/* Ug. If we got a gnutls_privkey_t from PKCS#11 rather than the
gnutls_x509_privkey_t that we get from PEM or PKCS#12 files, then
we can't use gnutls_certificate_set_x509_key(). Instead we have
to convert our chain of X509 certificates to gnutls_pcert_st and
then use gnutls_certificate_set_key() with that instead. */
gnutls_pcert_st *pcerts = calloc(nr_supporting_certs, sizeof(*pcerts));
if (!pcerts) {
ret = -ENOMEM;
goto out;
}
for (i=0 ; i < nr_supporting_certs; i++) {
err = gnutls_pcert_import_x509(pcerts + i, supporting_certs?supporting_certs[i]:cert, 0);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Importing X509 certificate failed: %s\n"),
gnutls_strerror(err));
goto free_pcerts;
}
}
err = gnutls_certificate_set_key(vpninfo->https_cred, NULL, 0, pcerts, nr_supporting_certs, pkey);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Setting PKCS#11 certificate failed: %s\n"),
gnutls_strerror(err));
free_pcerts:
for (i=0 ; i < nr_supporting_certs; i++)
gnutls_pcert_deinit(pcerts + i);
free (pcerts);
ret = -EIO;
goto out;
}
pkey = NULL; /* we gave it away, along with pcerts */
} else
#endif
err = gnutls_certificate_set_x509_key(vpninfo->https_cred,
supporting_certs ? supporting_certs : &cert,
supporting_certs ? nr_supporting_certs : 1,
key);
if (err) {
vpn_progress(vpninfo, PRG_ERR,
_("Setting certificate failed: %s\n"),
gnutls_strerror(err));
ret = -EIO;
}
out:
if (crl)
gnutls_x509_crl_deinit(crl);
if (key)
gnutls_x509_privkey_deinit(key);
if (cert)
gnutls_x509_crt_deinit(cert);
/* From 1 because cert is the first one (and might exist
even if supporting_certs is NULL) */
for (i = 1; i < certs_to_free; i++) {
if (supporting_certs[i])
gnutls_x509_crt_deinit(supporting_certs[i]);
}
for (i = 0; i < nr_extra_certs; i++) {
if (extra_certs[i])
gnutls_x509_crt_deinit(extra_certs[i]);
}
gnutls_free(extra_certs);
gnutls_free(supporting_certs);
gnutls_free(fdata.data);
#ifdef HAVE_P11KIT
if (pkey)
gnutls_privkey_deinit(pkey);
if (cert_url != vpninfo->cert)
free(cert_url);
if (key_url != vpninfo->sslkey)
free(key_url);
#endif
return ret;
}
static int get_cert_fingerprint(struct openconnect_info *vpninfo,
gnutls_x509_crt_t cert,
gnutls_digest_algorithm_t algo,
char *buf)
{
unsigned char md[256];
size_t md_size = sizeof(md);
unsigned int i;
if (gnutls_x509_crt_get_fingerprint(cert, algo, md, &md_size))
return -EIO;
for (i=0; i < md_size; i++)
sprintf(&buf[i*2], "%02X", md[i]);
return 0;
}
int get_cert_md5_fingerprint(struct openconnect_info *vpninfo,
OPENCONNECT_X509 *cert, char *buf)
{
return get_cert_fingerprint(vpninfo, cert, GNUTLS_DIG_MD5, buf);
}
int openconnect_get_cert_sha1(struct openconnect_info *vpninfo,
OPENCONNECT_X509 *cert, char *buf)
{
return get_cert_fingerprint(vpninfo, cert, GNUTLS_DIG_SHA1, buf);
}
char *openconnect_get_cert_details(struct openconnect_info *vpninfo,
OPENCONNECT_X509 *cert)
{
gnutls_datum_t buf;
char *ret;
if (gnutls_x509_crt_print(cert, GNUTLS_CRT_PRINT_FULL, &buf))
return NULL;
/* Just in case gnutls_free() isn't free(), we can't steal it. */
ret = strdup((char *)buf.data);
gnutls_free(buf.data);