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openssl.c
2004 lines (1725 loc) · 51.1 KB
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openssl.c
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/*
* OpenConnect (SSL + DTLS) VPN client
*
* Copyright © 2008-2015 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.
*/
#include <config.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <ctype.h>
#include "openconnect-internal.h"
#include <openssl/ssl.h>
#include <openssl/err.h>
#include <openssl/engine.h>
#include <openssl/evp.h>
#include <openssl/rand.h>
#include <openssl/pkcs12.h>
#include <openssl/x509v3.h>
#include <openssl/x509.h>
#include <openssl/bio.h>
#include <openssl/ui.h>
#include <openssl/rsa.h>
#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
#define X509_up_ref(x) CRYPTO_add(&(x)->references, 1, CRYPTO_LOCK_X509)
#define X509_get0_notAfter(x) X509_get_notAfter(x)
#define EVP_MD_CTX_new EVP_MD_CTX_create
#define EVP_MD_CTX_free EVP_MD_CTX_destroy
#define X509_STORE_CTX_get0_chain(ctx) ((ctx)->chain)
#define X509_STORE_CTX_get0_untrusted(ctx) ((ctx)->untrusted)
#define X509_STORE_CTX_get0_cert(ctx) ((ctx)->cert)
typedef int (*X509_STORE_CTX_get_issuer_fn)(X509 **issuer,
X509_STORE_CTX *ctx, X509 *x);
#define X509_STORE_CTX_get_get_issuer(ctx) ((ctx)->get_issuer)
#endif
int openconnect_sha1(unsigned char *result, void *data, int len)
{
EVP_MD_CTX *c = EVP_MD_CTX_new();
if (!c)
return -ENOMEM;
EVP_Digest(data, len, result, NULL, EVP_sha1(), NULL);
EVP_MD_CTX_free(c);
return 0;
}
int openconnect_sha256(unsigned char *result, void *data, int len)
{
EVP_MD_CTX *c = EVP_MD_CTX_new();
if (!c)
return -ENOMEM;
EVP_Digest(data, len, result, NULL, EVP_sha256(), NULL);
EVP_MD_CTX_free(c);
return 0;
}
int openconnect_md5(unsigned char *result, void *data, int len)
{
EVP_MD_CTX *c = EVP_MD_CTX_new();
if (!c)
return -ENOMEM;
EVP_Digest(data, len, result, NULL, EVP_md5(), NULL);
EVP_MD_CTX_free(c);
return 0;
}
int openconnect_get_peer_cert_DER(struct openconnect_info *vpninfo,
unsigned char **buf)
{
BIO *bp = BIO_new(BIO_s_mem());
BUF_MEM *certinfo;
size_t l;
if (!i2d_X509_bio(bp, vpninfo->peer_cert)) {
BIO_free(bp);
return -EIO;
}
BIO_get_mem_ptr(bp, &certinfo);
l = certinfo->length;
*buf = malloc(l);
if (!*buf) {
BIO_free(bp);
return -ENOMEM;
}
memcpy(*buf, certinfo->data, l);
BIO_free(bp);
return l;
}
int openconnect_random(void *bytes, int len)
{
if (RAND_bytes(bytes, len) != 1)
return -EIO;
return 0;
}
/* Helper functions for reading/writing lines over SSL.
We could use cURL for the HTTP stuff, but it's overkill */
static int _openconnect_openssl_write(SSL *ssl, int fd, struct openconnect_info *vpninfo, char *buf, size_t len)
{
size_t orig_len = len;
while (len) {
int done = SSL_write(ssl, buf, len);
if (done > 0)
len -= done;
else {
int err = SSL_get_error(ssl, done);
fd_set wr_set, rd_set;
int maxfd = fd;
FD_ZERO(&wr_set);
FD_ZERO(&rd_set);
if (err == SSL_ERROR_WANT_READ)
FD_SET(fd, &rd_set);
else if (err == SSL_ERROR_WANT_WRITE)
FD_SET(fd, &wr_set);
else {
vpn_progress(vpninfo, PRG_ERR, _("Failed to write to SSL socket\n"));
openconnect_report_ssl_errors(vpninfo);
return -EIO;
}
cmd_fd_set(vpninfo, &rd_set, &maxfd);
select(maxfd + 1, &rd_set, &wr_set, NULL, NULL);
if (is_cancel_pending(vpninfo, &rd_set)) {
vpn_progress(vpninfo, PRG_ERR, _("SSL write cancelled\n"));
return -EINTR;
}
}
}
return orig_len;
}
static int openconnect_openssl_write(struct openconnect_info *vpninfo, char *buf, size_t len)
{
return _openconnect_openssl_write(vpninfo->https_ssl, vpninfo->ssl_fd, vpninfo, buf, len);
}
int openconnect_dtls_write(struct openconnect_info *vpninfo, void *buf, size_t len)
{
return _openconnect_openssl_write(vpninfo->dtls_ssl, vpninfo->dtls_fd, vpninfo, buf, len);
}
/* set ms to zero for no timeout */
static int _openconnect_openssl_read(SSL *ssl, int fd, struct openconnect_info *vpninfo, char *buf, size_t len, unsigned ms)
{
int done, ret;
struct timeval timeout, *tv = NULL;
if (ms) {
timeout.tv_sec = ms/1000;
timeout.tv_usec = (ms%1000)*1000;
tv = &timeout;
}
while ((done = SSL_read(ssl, buf, len)) == -1) {
int err = SSL_get_error(ssl, done);
fd_set wr_set, rd_set;
int maxfd = fd;
FD_ZERO(&wr_set);
FD_ZERO(&rd_set);
if (err == SSL_ERROR_WANT_READ)
FD_SET(fd, &rd_set);
else if (err == SSL_ERROR_WANT_WRITE)
FD_SET(fd, &wr_set);
else {
vpn_progress(vpninfo, PRG_ERR, _("Failed to read from SSL socket\n"));
openconnect_report_ssl_errors(vpninfo);
return -EIO;
}
cmd_fd_set(vpninfo, &rd_set, &maxfd);
ret = select(maxfd + 1, &rd_set, &wr_set, NULL, tv);
if (is_cancel_pending(vpninfo, &rd_set)) {
vpn_progress(vpninfo, PRG_ERR, _("SSL read cancelled\n"));
return -EINTR;
}
if (ret == 0) {
return -ETIMEDOUT;
}
}
return done;
}
static int openconnect_openssl_read(struct openconnect_info *vpninfo, char *buf, size_t len)
{
return _openconnect_openssl_read(vpninfo->https_ssl, vpninfo->ssl_fd, vpninfo, buf, len, 0);
}
int openconnect_dtls_read(struct openconnect_info *vpninfo, void *buf, size_t len, unsigned ms)
{
return _openconnect_openssl_read(vpninfo->dtls_ssl, vpninfo->dtls_fd, vpninfo, buf, len, ms);
}
static int openconnect_openssl_gets(struct openconnect_info *vpninfo, char *buf, size_t len)
{
int i = 0;
int ret;
if (len < 2)
return -EINVAL;
while (1) {
ret = SSL_read(vpninfo->https_ssl, 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 {
fd_set rd_set, wr_set;
int maxfd = vpninfo->ssl_fd;
FD_ZERO(&rd_set);
FD_ZERO(&wr_set);
ret = SSL_get_error(vpninfo->https_ssl, ret);
if (ret == SSL_ERROR_WANT_READ)
FD_SET(vpninfo->ssl_fd, &rd_set);
else if (ret == SSL_ERROR_WANT_WRITE)
FD_SET(vpninfo->ssl_fd, &wr_set);
else {
vpn_progress(vpninfo, PRG_ERR, _("Failed to read from SSL socket\n"));
openconnect_report_ssl_errors(vpninfo);
ret = -EIO;
break;
}
cmd_fd_set(vpninfo, &rd_set, &maxfd);
select(maxfd + 1, &rd_set, &wr_set, NULL, NULL);
if (is_cancel_pending(vpninfo, &rd_set)) {
vpn_progress(vpninfo, PRG_ERR, _("SSL read cancelled\n"));
ret = -EINTR;
break;
}
}
}
buf[i] = 0;
return i ?: ret;
}
int ssl_nonblock_read(struct openconnect_info *vpninfo, void *buf, int maxlen)
{
int len, ret;
len = SSL_read(vpninfo->https_ssl, buf, maxlen);
if (len > 0)
return len;
ret = SSL_get_error(vpninfo->https_ssl, len);
if (ret == SSL_ERROR_SYSCALL || ret == SSL_ERROR_ZERO_RETURN) {
vpn_progress(vpninfo, PRG_ERR,
_("SSL read error %d (server probably closed connection); reconnecting.\n"),
ret);
return -EIO;
}
return 0;
}
int ssl_nonblock_write(struct openconnect_info *vpninfo, void *buf, int buflen)
{
int ret;
ret = SSL_write(vpninfo->https_ssl, buf, buflen);
if (ret > 0)
return ret;
ret = SSL_get_error(vpninfo->https_ssl, ret);
switch (ret) {
case SSL_ERROR_WANT_WRITE:
/* Waiting for the socket to become writable -- it's
probably stalled, and/or the buffers are full */
monitor_write_fd(vpninfo, ssl);
case SSL_ERROR_WANT_READ:
return 0;
default:
vpn_progress(vpninfo, PRG_ERR, _("SSL_write failed: %d\n"), ret);
openconnect_report_ssl_errors(vpninfo);
return -1;
}
}
/* UI handling. All this just to handle the PIN callback from the TPM ENGINE,
and turn it into a call to our ->process_auth_form function */
struct ui_data {
struct openconnect_info *vpninfo;
struct oc_form_opt **last_opt;
struct oc_auth_form form;
};
struct ui_form_opt {
struct oc_form_opt opt;
UI_STRING *uis;
};
#ifdef HAVE_ENGINE
/* Ick. But there is no way to pass this sanely through OpenSSL */
static struct openconnect_info *ui_vpninfo;
static int ui_open(UI *ui)
{
struct openconnect_info *vpninfo = ui_vpninfo; /* Ick */
struct ui_data *ui_data;
if (!vpninfo || !vpninfo->process_auth_form)
return 0;
ui_data = malloc(sizeof(*ui_data));
if (!ui_data)
return 0;
memset(ui_data, 0, sizeof(*ui_data));
ui_data->last_opt = &ui_data->form.opts;
ui_data->vpninfo = vpninfo;
ui_data->form.auth_id = (char *)"openssl_ui";
UI_add_user_data(ui, ui_data);
return 1;
}
static int ui_write(UI *ui, UI_STRING *uis)
{
struct ui_data *ui_data = UI_get0_user_data(ui);
struct ui_form_opt *opt;
switch (UI_get_string_type(uis)) {
case UIT_ERROR:
ui_data->form.error = (char *)UI_get0_output_string(uis);
break;
case UIT_INFO:
ui_data->form.message = (char *)UI_get0_output_string(uis);
break;
case UIT_PROMPT:
opt = malloc(sizeof(*opt));
if (!opt)
return 1;
memset(opt, 0, sizeof(*opt));
opt->uis = uis;
opt->opt.label = opt->opt.name = (char *)UI_get0_output_string(uis);
if (UI_get_input_flags(uis) & UI_INPUT_FLAG_ECHO)
opt->opt.type = OC_FORM_OPT_TEXT;
else
opt->opt.type = OC_FORM_OPT_PASSWORD;
*(ui_data->last_opt) = &opt->opt;
ui_data->last_opt = &opt->opt.next;
break;
default:
vpn_progress(ui_data->vpninfo, PRG_ERR,
_("Unhandled SSL UI request type %d\n"),
UI_get_string_type(uis));
return 0;
}
return 1;
}
static int ui_flush(UI *ui)
{
struct ui_data *ui_data = UI_get0_user_data(ui);
struct openconnect_info *vpninfo = ui_data->vpninfo;
struct ui_form_opt *opt;
int ret;
ret = process_auth_form(vpninfo, &ui_data->form);
if (ret)
return 0;
for (opt = (struct ui_form_opt *)ui_data->form.opts; opt;
opt = (struct ui_form_opt *)opt->opt.next) {
if (opt->opt._value && opt->uis)
UI_set_result(ui, opt->uis, opt->opt._value);
}
return 1;
}
static int ui_close(UI *ui)
{
struct ui_data *ui_data = UI_get0_user_data(ui);
struct ui_form_opt *opt, *next_opt;
opt = (struct ui_form_opt *)ui_data->form.opts;
while (opt) {
next_opt = (struct ui_form_opt *)opt->opt.next;
if (opt->opt._value)
free(opt->opt._value);
free(opt);
opt = next_opt;
}
free(ui_data);
UI_add_user_data(ui, NULL);
return 1;
}
static UI_METHOD *create_openssl_ui(struct openconnect_info *vpninfo)
{
UI_METHOD *ui_method = UI_create_method((char *)"AnyConnect VPN UI");
/* There is a race condition here because of the use of the
static ui_vpninfo pointer. This sucks, but it's OpenSSL's
fault and in practice it's *never* going to hurt us.
This UI is only used for loading certificates from a TPM; for
PKCS#12 and PEM files we hook the passphrase request differently.
The ui_vpninfo variable is set here, and is used from ui_open()
when the TPM ENGINE decides it needs to ask the user for a PIN.
The race condition exists because theoretically, there
could be more than one thread using libopenconnect and
trying to authenticate to a VPN server, within the *same*
process. And if *both* are using certificates from the TPM,
and *both* manage to be within that short window of time
between setting ui_vpninfo and invoking ui_open() to fetch
the PIN, then one connection's ->process_auth_form() could
get a PIN request for the *other* connection.
However, the only thing that ever does run libopenconnect more
than once from the same process is KDE's NetworkManager support,
and NetworkManager doesn't *support* having more than one VPN
connected anyway, so first that would have to be fixed and then
you'd have to connect to two VPNs simultaneously by clicking
'connect' on both at *exactly* the same time and then getting
*really* unlucky.
Oh, and the KDE support won't be using OpenSSL anyway because of
licensing conflicts... so although this sucks, I'm not going to
lose sleep over it.
*/
ui_vpninfo = vpninfo;
/* Set up a UI method of our own for password/passphrase requests */
UI_method_set_opener(ui_method, ui_open);
UI_method_set_writer(ui_method, ui_write);
UI_method_set_flusher(ui_method, ui_flush);
UI_method_set_closer(ui_method, ui_close);
return ui_method;
}
#endif
static int pem_pw_cb(char *buf, int len, int w, void *v)
{
struct openconnect_info *vpninfo = v;
char *pass = NULL;
int plen;
if (vpninfo->cert_password) {
pass = vpninfo->cert_password;
vpninfo->cert_password = NULL;
} else if (request_passphrase(vpninfo, "openconnect_pem",
&pass, _("Enter PEM pass phrase:")))
return -1;
plen = strlen(pass);
if (len <= plen) {
vpn_progress(vpninfo, PRG_ERR,
_("PEM password too long (%d >= %d)\n"),
plen, len);
free(pass);
return -1;
}
memcpy(buf, pass, plen+1);
free(pass);
return plen;
}
static int install_extra_certs(struct openconnect_info *vpninfo, const char *source,
STACK_OF(X509) *ca)
{
X509 *cert = vpninfo->cert_x509;
int i;
if (!cert)
return -EINVAL;
next:
for (i = 0; i < sk_X509_num(ca); i++) {
X509 *cert2 = sk_X509_value(ca, i);
if (X509_check_issued(cert2, cert) == X509_V_OK) {
char buf[200];
if (cert2 == cert)
break;
if (X509_check_issued(cert2, cert2) == X509_V_OK)
break;
X509_NAME_oneline(X509_get_subject_name(cert2),
buf, sizeof(buf));
vpn_progress(vpninfo, PRG_DEBUG,
_("Extra cert from %s: '%s'\n"), source, buf);
X509_up_ref(cert2);
SSL_CTX_add_extra_chain_cert(vpninfo->https_ctx, cert2);
cert = cert2;
goto next;
}
}
sk_X509_pop_free(ca, X509_free);
return 0;
}
static int load_pkcs12_certificate(struct openconnect_info *vpninfo, PKCS12 *p12)
{
EVP_PKEY *pkey = NULL;
X509 *cert = NULL;
STACK_OF(X509) *ca;
int ret = 0;
char *pass;
pass = vpninfo->cert_password;
vpninfo->cert_password = NULL;
retrypass:
/* We do this every time round the loop, to work around a bug in
OpenSSL < 1.0.0-beta2 -- where the stack at *ca will be freed
when PKCS12_parse() returns an error, but *ca is left pointing
to the freed memory. */
ca = NULL;
if (!PKCS12_parse(p12, pass, &pkey, &cert, &ca)) {
unsigned long err = ERR_peek_error();
if (ERR_GET_LIB(err) == ERR_LIB_PKCS12 &&
ERR_GET_FUNC(err) == PKCS12_F_PKCS12_PARSE &&
ERR_GET_REASON(err) == PKCS12_R_MAC_VERIFY_FAILURE) {
if (pass)
vpn_progress(vpninfo, PRG_ERR,
_("Failed to decrypt PKCS#12 certificate file\n"));
free(pass);
if (request_passphrase(vpninfo, "openconnect_pkcs12", &pass,
_("Enter PKCS#12 pass phrase:")) < 0) {
PKCS12_free(p12);
return -EINVAL;
}
goto retrypass;
}
openconnect_report_ssl_errors(vpninfo);
vpn_progress(vpninfo, PRG_ERR,
_("Parse PKCS#12 failed (see above errors)\n"));
PKCS12_free(p12);
free(pass);
return -EINVAL;
}
free(pass);
if (cert) {
char buf[200];
vpninfo->cert_x509 = cert;
SSL_CTX_use_certificate(vpninfo->https_ctx, cert);
X509_NAME_oneline(X509_get_subject_name(cert), buf, sizeof(buf));
vpn_progress(vpninfo, PRG_INFO,
_("Using client certificate '%s'\n"), buf);
} else {
vpn_progress(vpninfo, PRG_ERR,
_("PKCS#12 contained no certificate!\n"));
ret = -EINVAL;
}
if (pkey) {
SSL_CTX_use_PrivateKey(vpninfo->https_ctx, pkey);
EVP_PKEY_free(pkey);
} else {
vpn_progress(vpninfo, PRG_ERR,
_("PKCS#12 contained no private key!\n"));
ret = -EINVAL;
}
if (ca)
install_extra_certs(vpninfo, _("PKCS#12"), ca);
PKCS12_free(p12);
return ret;
}
#ifdef HAVE_ENGINE
static int load_tpm_certificate(struct openconnect_info *vpninfo)
{
ENGINE *e;
EVP_PKEY *key;
UI_METHOD *meth = NULL;
int ret = 0;
ENGINE_load_builtin_engines();
e = ENGINE_by_id("tpm");
if (!e) {
vpn_progress(vpninfo, PRG_ERR, _("Can't load TPM engine.\n"));
openconnect_report_ssl_errors(vpninfo);
return -EINVAL;
}
if (!ENGINE_init(e) || !ENGINE_set_default_RSA(e) ||
!ENGINE_set_default_RAND(e)) {
vpn_progress(vpninfo, PRG_ERR, _("Failed to init TPM engine\n"));
openconnect_report_ssl_errors(vpninfo);
ENGINE_free(e);
return -EINVAL;
}
if (vpninfo->cert_password) {
if (!ENGINE_ctrl_cmd(e, "PIN", strlen(vpninfo->cert_password),
vpninfo->cert_password, NULL, 0)) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to set TPM SRK password\n"));
openconnect_report_ssl_errors(vpninfo);
}
vpninfo->cert_password = NULL;
free(vpninfo->cert_password);
} else {
/* Provide our own UI method to handle the PIN callback. */
meth = create_openssl_ui(vpninfo);
}
key = ENGINE_load_private_key(e, vpninfo->sslkey, meth, NULL);
if (meth)
UI_destroy_method(meth);
if (!key) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to load TPM private key\n"));
openconnect_report_ssl_errors(vpninfo);
ret = -EINVAL;
goto out;
}
if (!SSL_CTX_use_PrivateKey(vpninfo->https_ctx, key)) {
vpn_progress(vpninfo, PRG_ERR, _("Add key from TPM failed\n"));
openconnect_report_ssl_errors(vpninfo);
ret = -EINVAL;
}
EVP_PKEY_free(key);
out:
ENGINE_finish(e);
ENGINE_free(e);
return ret;
}
#else
static int load_tpm_certificate(struct openconnect_info *vpninfo)
{
vpn_progress(vpninfo, PRG_ERR,
_("This version of OpenConnect was built without TPM support\n"));
return -EINVAL;
}
#endif
/* This is a reimplementation of SSL_CTX_use_certificate_chain_file().
* We do this for three reasons:
*
* - Firstly, we have no way to obtain the primary X509 certificate
* after SSL_CTX_use_certificate_chain_file() has loaded it, and we
* need to inspect it to check for expiry and report its name etc.
* So in the past we've opened the cert file again and read the cert
* again in a reload_pem_cert() function which was a partial
* reimplementation anyway.
*
* - Secondly, on Windows, OpenSSL only partially handles UTF-8 filenames.
* Specifically, BIO_new_file() will convert UTF-8 to UTF-16 and attempt
* to use _wfopen() to open the file, but BIO_read_filename() will not.
* It is BIO_read_filename() which the SSL_CTX_*_file functions use, and
* thus they don't work with UTF-8 file names. This is filed as RT#3479:
* http://rt.openssl.org/Ticket/Display.html?id=3479
*
* - Finally, and least importantly, it does actually matter which supporting
* certs we offer on the wire because of RT#1942. Doing this for ourselves
* allows us to explicitly print the supporting certs that we're using,
* which may assist in diagnosing problems.
*/
static int load_cert_chain_file(struct openconnect_info *vpninfo)
{
BIO *b;
FILE *f = openconnect_fopen_utf8(vpninfo, vpninfo->cert, "rb");
STACK_OF(X509) *extra_certs = NULL;
char buf[200];
if (!f) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to open certificate file %s: %s\n"),
vpninfo->cert, strerror(errno));
return -ENOENT;
}
b = BIO_new_fp(f, 1);
if (!b) {
fclose(f);
err:
vpn_progress(vpninfo, PRG_ERR,
_("Loading certificate failed\n"));
openconnect_report_ssl_errors(vpninfo);
return -EIO;
}
vpninfo->cert_x509 = PEM_read_bio_X509_AUX(b, NULL, NULL, NULL);
if (!vpninfo->cert_x509) {
BIO_free(b);
goto err;
}
X509_NAME_oneline(X509_get_subject_name(vpninfo->cert_x509), buf, sizeof(buf));
vpn_progress(vpninfo, PRG_INFO,
_("Using client certificate '%s'\n"), buf);
if (!SSL_CTX_use_certificate(vpninfo->https_ctx, vpninfo->cert_x509)) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to install certificate in OpenSSL context\n"));
openconnect_report_ssl_errors(vpninfo);
BIO_free(b);
return -EIO;
}
while (1) {
X509 *x = PEM_read_bio_X509(b, NULL, NULL, NULL);
if (!x) {
unsigned long err = ERR_peek_last_error();
if (ERR_GET_LIB(err) == ERR_LIB_PEM &&
ERR_GET_REASON(err) == PEM_R_NO_START_LINE)
ERR_clear_error();
else
goto err_extra;
break;
}
if (!extra_certs)
extra_certs = sk_X509_new_null();
if (!extra_certs) {
err_extra:
vpn_progress(vpninfo, PRG_ERR,
_("Failed to process all supporting certs. Trying anyway...\n"));
openconnect_report_ssl_errors(vpninfo);
X509_free(x);
/* It might work without... */
break;
}
if (!sk_X509_push(extra_certs, x))
goto err_extra;
}
BIO_free(b);
if (extra_certs)
install_extra_certs(vpninfo, _("PEM file"), extra_certs);
return 0;
}
#ifdef ANDROID_KEYSTORE
static BIO *BIO_from_keystore(struct openconnect_info *vpninfo, const char *item)
{
unsigned char *content;
BIO *b;
int len;
const char *p = item + 9;
/* Skip first two slashes if the user has given it as
keystore://foo ... */
if (*p == '/')
p++;
if (*p == '/')
p++;
len = keystore_fetch(p, &content);
if (len < 0) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to load item '%s' from keystore: %s\n"),
p, keystore_strerror(len));
return NULL;
}
if (!(b = BIO_new(BIO_s_mem())) || BIO_write(b, content, len) != len) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to create BIO for keystore item '%s'\n"),
p);
free(content);
BIO_free(b);
return NULL;
}
free(content);
return b;
}
#endif
static int is_pem_password_error(struct openconnect_info *vpninfo)
{
unsigned long err = ERR_peek_error();
openconnect_report_ssl_errors(vpninfo);
#ifndef EVP_F_EVP_DECRYPTFINAL_EX
#define EVP_F_EVP_DECRYPTFINAL_EX EVP_F_EVP_DECRYPTFINAL
#endif
/* If the user fat-fingered the passphrase, try again */
if (ERR_GET_LIB(err) == ERR_LIB_EVP &&
ERR_GET_FUNC(err) == EVP_F_EVP_DECRYPTFINAL_EX &&
ERR_GET_REASON(err) == EVP_R_BAD_DECRYPT) {
vpn_progress(vpninfo, PRG_ERR,
_("Loading private key failed (wrong passphrase?)\n"));
ERR_clear_error();
return 1;
}
vpn_progress(vpninfo, PRG_ERR,
_("Loading private key failed (see above errors)\n"));
return 0;
}
static int load_certificate(struct openconnect_info *vpninfo)
{
EVP_PKEY *key;
FILE *f;
char buf[256];
int ret;
if (!strncmp(vpninfo->cert, "pkcs11:", 7)) {
int ret = load_pkcs11_certificate(vpninfo);
if (ret)
return ret;
goto got_cert;
}
vpn_progress(vpninfo, PRG_DEBUG,
_("Using certificate file %s\n"), vpninfo->cert);
if (strncmp(vpninfo->cert, "keystore:", 9)) {
PKCS12 *p12;
f = openconnect_fopen_utf8(vpninfo, vpninfo->cert, "rb");
if (!f) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to open certificate file %s: %s\n"),
vpninfo->cert, strerror(errno));
return -ENOENT;
}
p12 = d2i_PKCS12_fp(f, NULL);
fclose(f);
if (p12)
return load_pkcs12_certificate(vpninfo, p12);
/* Not PKCS#12. Clear error and fall through to see if it's a PEM file... */
ERR_clear_error();
}
/* It's PEM or TPM now, and either way we need to load the plain cert: */
#ifdef ANDROID_KEYSTORE
if (!strncmp(vpninfo->cert, "keystore:", 9)) {
BIO *b = BIO_from_keystore(vpninfo, vpninfo->cert);
if (!b)
return -EINVAL;
vpninfo->cert_x509 = PEM_read_bio_X509_AUX(b, NULL, pem_pw_cb, vpninfo);
BIO_free(b);
if (!vpninfo->cert_x509) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to load X509 certificate from keystore\n"));
openconnect_report_ssl_errors(vpninfo);
return -EINVAL;
}
if (!SSL_CTX_use_certificate(vpninfo->https_ctx, vpninfo->cert_x509)) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to use X509 certificate from keystore\n"));
openconnect_report_ssl_errors(vpninfo);
X509_free(vpninfo->cert_x509);
vpninfo->cert_x509 = NULL;
return -EINVAL;
}
} else
#endif /* ANDROID_KEYSTORE */
{
int ret = load_cert_chain_file(vpninfo);
if (ret)
return ret;
}
got_cert:
#ifdef ANDROID_KEYSTORE
if (!strncmp(vpninfo->sslkey, "keystore:", 9)) {
BIO *b;
again_android:
b = BIO_from_keystore(vpninfo, vpninfo->sslkey);
if (!b)
return -EINVAL;
key = PEM_read_bio_PrivateKey(b, NULL, pem_pw_cb, vpninfo);
BIO_free(b);
if (!key) {
if (is_pem_password_error(vpninfo))
goto again_android;
return -EINVAL;
}
if (!SSL_CTX_use_PrivateKey(vpninfo->https_ctx, key)) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to use private key from keystore\n"));
EVP_PKEY_free(key);
X509_free(vpninfo->cert_x509);
vpninfo->cert_x509 = NULL;
return -EINVAL;
}
EVP_PKEY_free(key);
return 0;
}
#endif /* ANDROID_KEYSTORE */
if (!strncmp(vpninfo->sslkey, "pkcs11:", 7))
return load_pkcs11_key(vpninfo);
f = openconnect_fopen_utf8(vpninfo, vpninfo->sslkey, "rb");
if (!f) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to open private key file %s: %s\n"),
vpninfo->sslkey, strerror(errno));
return -ENOENT;
}
buf[255] = 0;
while (fgets(buf, 255, f)) {
if (!strcmp(buf, "-----BEGIN TSS KEY BLOB-----\n")) {
fclose(f);
return load_tpm_certificate(vpninfo);
} else if (!strcmp(buf, "-----BEGIN RSA PRIVATE KEY-----\n") ||
!strcmp(buf, "-----BEGIN DSA PRIVATE KEY-----\n") ||
!strcmp(buf, "-----BEGIN EC PRIVATE KEY-----\n") ||
!strcmp(buf, "-----BEGIN ENCRYPTED PRIVATE KEY-----\n") ||
!strcmp(buf, "-----BEGIN PRIVATE KEY-----\n")) {
BIO *b = BIO_new_fp(f, BIO_CLOSE);
if (!b) {
fclose(f);
vpn_progress(vpninfo, PRG_ERR,
_("Loading private key failed\n"));
openconnect_report_ssl_errors(vpninfo);
}
again:
fseek(f, 0, SEEK_SET);
key = PEM_read_bio_PrivateKey(b, NULL, pem_pw_cb, vpninfo);
if (!key) {
if (is_pem_password_error(vpninfo))
goto again;
BIO_free(b);
return -EINVAL;
}
ret = 0;
if (!SSL_CTX_use_PrivateKey(vpninfo->https_ctx, key)) {
vpn_progress(vpninfo, PRG_ERR,
_("Loading private key failed\n"));
openconnect_report_ssl_errors(vpninfo);
ret = -EINVAL;
}
EVP_PKEY_free(key);
BIO_free(b);
return ret;
}
}
/* Not PEM? Try DER... */
fseek(f, 0, SEEK_SET);
/* This will catch PKCS#1 and unencrypted PKCS#8
* (except in OpenSSL 0.9.8 where it doesn't handle
* the latter but nobody cares about 0.9.8 any more. */
key = d2i_PrivateKey_fp(f, NULL);
if (key) {
ret = 0;
if (!SSL_CTX_use_PrivateKey(vpninfo->https_ctx, key)) {
vpn_progress(vpninfo, PRG_ERR,
_("Loading private key failed\n"));
openconnect_report_ssl_errors(vpninfo);
ret = -EINVAL;
}
EVP_PKEY_free(key);