/
openssl.c
2176 lines (1869 loc) · 54.8 KB
/
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/crypto.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
static char tls_library_version[32] = "";
const char *openconnect_get_tls_library_version()
{
if (!*tls_library_version) {
strncpy(tls_library_version, SSLeay_version(SSLEAY_VERSION), sizeof(tls_library_version));
tls_library_version[sizeof(tls_library_version)-1]='\0';
}
return tls_library_version;
}
int can_enable_insecure_crypto()
{
int ret = 0;
if (setenv("OPENSSL_CONF", DEVNULL, 1) < 0)
return -errno;
/* FIXME: deinitialize and reinitialize library, as is done for GnuTLS,
* to ensure that updated value is used.
*
* Cleaning up and reinitalizing OpenSSL appears to be complex:
* https://wiki.openssl.org/index.php/Library_Initialization#Cleanup
*/
if (EVP_des_ede3_cbc() == NULL ||
EVP_rc4() == NULL)
ret = -ENOENT;
return ret;
}
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 TLS/DTLS.
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 TLS/DTLS 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, _("TLS/DTLS 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 TLS/DTLS 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, _("TLS/DTLS 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 TLS/DTLS 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, _("TLS/DTLS 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
static int ui_open(UI *ui)
{
struct openconnect_info *vpninfo = UI_get0_user_data(ui);
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(void)
{
UI_METHOD *ui_method = UI_create_method((char *)"AnyConnect VPN UI");
/* 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(&pass);
return -1;
}
memcpy(buf, pass, plen+1);
free_pass(&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(&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(&pass);
return -EINVAL;
}
free_pass(&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) {
if (!SSL_CTX_use_PrivateKey(vpninfo->https_ctx, pkey)) {
vpn_progress(vpninfo, PRG_ERR,
_("Loading private key failed\n"));
openconnect_report_ssl_errors(vpninfo);
ret = -EINVAL;
}
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,
const char *engine)
{
ENGINE *e;
EVP_PKEY *key;
UI_METHOD *meth = NULL;
int ret = 0;
ENGINE_load_builtin_engines();
e = ENGINE_by_id(engine);
if (!e && !strcmp(engine, "tpm2")) {
ERR_clear_error();
e = ENGINE_by_id("tpm2tss");
}
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);
}
free_pass(&vpninfo->cert_password);
}
/* Provide our own UI method to handle the PIN callback. */
meth = create_openssl_ui();
key = ENGINE_load_private_key(e, vpninfo->sslkey, meth, vpninfo);
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,
const char *engine)
{
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, "tpm");
} else if (!strcmp(buf, "-----BEGIN TSS2 KEY BLOB-----\n") ||
!strcmp(buf, "-----BEGIN TSS2 PRIVATE KEY-----\n")) {
fclose(f);
return load_tpm_certificate(vpninfo, "tpm2");
} 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);
return -EINVAL;
}
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... */