diff options
Diffstat (limited to 'src/gnutls.c')
| -rw-r--r-- | src/gnutls.c | 1116 |
1 files changed, 1116 insertions, 0 deletions
diff --git a/src/gnutls.c b/src/gnutls.c new file mode 100644 index 0000000..5706dbb --- /dev/null +++ b/src/gnutls.c @@ -0,0 +1,1116 @@ +/* SSL support via GnuTLS library. + Copyright (C) 2005-2012, 2015, 2018-2020 Free Software Foundation, + Inc. + +This file is part of GNU Wget. + +GNU Wget is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 3 of the License, or +(at your option) any later version. + +GNU Wget 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 General Public License for more details. + +You should have received a copy of the GNU General Public License +along with Wget. If not, see <http://www.gnu.org/licenses/>. + +Additional permission under GNU GPL version 3 section 7 + +If you modify this program, or any covered work, by linking or +combining it with the OpenSSL project's OpenSSL library (or a +modified version of that library), containing parts covered by the +terms of the OpenSSL or SSLeay licenses, the Free Software Foundation +grants you additional permission to convey the resulting work. +Corresponding Source for a non-source form of such a combination +shall include the source code for the parts of OpenSSL used as well +as that of the covered work. */ + +#include "wget.h" + +#include <errno.h> +#include <unistd.h> +#include <string.h> +#include <stdio.h> +#include <dirent.h> +#include <stdlib.h> +#include <xalloc.h> + +#include <gnutls/abstract.h> +#include <gnutls/gnutls.h> +#include <gnutls/x509.h> +#include <sys/ioctl.h> + +#include "utils.h" +#include "connect.h" +#include "url.h" +#include "ptimer.h" +#include "hash.h" +#include "ssl.h" + +#include <fcntl.h> + +#ifdef WIN32 +# include "w32sock.h" +#endif + +#include "host.h" + +struct st_read_timer +{ + double timeout; + double next_timeout; + struct ptimer *timer; + int timed_out; +}; + +static int +_do_handshake (gnutls_session_t session, int fd, struct st_read_timer *timeout); + +#if GNUTLS_VERSION_NUMBER >= 0x030604 +static int +_do_reauth (gnutls_session_t session, int fd, struct st_read_timer *timeout); +#endif + +static int +key_type_to_gnutls_type (enum keyfile_type type) +{ + switch (type) + { + case keyfile_pem: + return GNUTLS_X509_FMT_PEM; + case keyfile_asn1: + return GNUTLS_X509_FMT_DER; + default: + abort (); + } +} + +/* Note: some of the functions private to this file have names that + begin with "wgnutls_" (e.g. wgnutls_read) so that they wouldn't be + confused with actual gnutls functions -- such as the gnutls_read + preprocessor macro. */ + +static gnutls_certificate_credentials_t credentials; +bool +ssl_init (void) +{ + /* Becomes true if GnuTLS is initialized. */ + static bool ssl_initialized = false; + const char *ca_directory; + DIR *dir; + int ncerts = -1; + int rc; + + /* GnuTLS should be initialized only once. */ + if (ssl_initialized) + return true; + + gnutls_global_init (); + gnutls_certificate_allocate_credentials (&credentials); + gnutls_certificate_set_verify_flags (credentials, + GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT); + +#if GNUTLS_VERSION_MAJOR >= 3 + if (!opt.ca_directory) + ncerts = gnutls_certificate_set_x509_system_trust (credentials); +#endif + + /* If GnuTLS version is too old or CA loading failed, fallback to old behaviour. + * Also use old behaviour if the CA directory is user-provided. */ + if (ncerts <= 0) + { + ncerts = 0; + + ca_directory = opt.ca_directory ? opt.ca_directory : "/etc/ssl/certs"; + + if ((dir = opendir (ca_directory)) == NULL) + { + if (opt.ca_directory && *opt.ca_directory) + logprintf (LOG_NOTQUIET, _("ERROR: Cannot open directory %s.\n"), + opt.ca_directory); + } + else + { + struct hash_table *inode_map = hash_table_new (196, NULL, NULL); + struct dirent *dent; + + while ((dent = readdir (dir)) != NULL) + { + struct stat st; + char ca_file[1024]; + + if (((unsigned) snprintf (ca_file, sizeof (ca_file), "%s/%s", ca_directory, dent->d_name)) >= sizeof (ca_file)) + continue; // overflow + + if (stat (ca_file, &st) != 0) + continue; + + if (! S_ISREG (st.st_mode)) + continue; + + /* avoid loading the same file twice by checking the inode. */ + if (hash_table_contains (inode_map, (void *)(intptr_t) st.st_ino)) + continue; + + hash_table_put (inode_map, (void *)(intptr_t) st.st_ino, NULL); + if ((rc = gnutls_certificate_set_x509_trust_file (credentials, ca_file, + GNUTLS_X509_FMT_PEM)) <= 0) + DEBUGP (("WARNING: Failed to open cert %s: (%d).\n", ca_file, rc)); + else + ncerts += rc; + } + + hash_table_destroy (inode_map); + closedir (dir); + } + } + + if (opt.ca_cert) + { + if (ncerts < 0) + ncerts = 0; + + if ((rc = gnutls_certificate_set_x509_trust_file (credentials, opt.ca_cert, + GNUTLS_X509_FMT_PEM)) <= 0) + logprintf (LOG_NOTQUIET, _("ERROR: Failed to open cert %s: (%d).\n"), + opt.ca_cert, rc); + else + { + ncerts += rc; + logprintf (LOG_VERBOSE, _("Loaded CA certificate '%s'\n"), opt.ca_cert); + } + } + + if (opt.crl_file) + { + if ((rc = gnutls_certificate_set_x509_crl_file (credentials, opt.crl_file, GNUTLS_X509_FMT_PEM)) <= 0) + { + logprintf (LOG_NOTQUIET, _("ERROR: Failed to load CRL file '%s': (%d)\n"), opt.crl_file, rc); + return false; + } + + logprintf (LOG_VERBOSE, _("Loaded CRL file '%s'\n"), opt.crl_file); + } + + DEBUGP (("Certificates loaded: %d\n", ncerts)); + + /* Use the private key from the cert file unless otherwise specified. */ + if (opt.cert_file && !opt.private_key) + { + opt.private_key = xstrdup (opt.cert_file); + opt.private_key_type = opt.cert_type; + } + /* Use the cert from the private key file unless otherwise specified. */ + if (!opt.cert_file && opt.private_key) + { + opt.cert_file = xstrdup (opt.private_key); + opt.cert_type = opt.private_key_type; + } + + if (opt.cert_file && opt.private_key) + { + int type; + if (opt.private_key_type != opt.cert_type) + { + /* GnuTLS can't handle this */ + logprintf (LOG_NOTQUIET, _("ERROR: GnuTLS requires the key and the \ +cert to be of the same type.\n")); + } + + type = key_type_to_gnutls_type (opt.private_key_type); + + gnutls_certificate_set_x509_key_file (credentials, opt.cert_file, + opt.private_key, + type); + } + + ssl_initialized = true; + + return true; +} + +void +ssl_cleanup (void) +{ + if (credentials) + gnutls_certificate_free_credentials(credentials); + + gnutls_global_deinit(); +} + +struct wgnutls_transport_context +{ + gnutls_session_t session; /* GnuTLS session handle */ + gnutls_datum_t *session_data; + int last_error; /* last error returned by read/write/... */ + + /* Since GnuTLS doesn't support the equivalent to recv(..., + MSG_PEEK) or SSL_peek(), we have to do it ourselves. Peeked data + is stored to PEEKBUF, and wgnutls_read checks that buffer before + actually reading. */ + char peekbuf[512]; + int peeklen; +}; + +static int +wgnutls_read_timeout (int fd, char *buf, int bufsize, void *arg, double timeout) +{ +#ifdef F_GETFL + int flags = 0; +#endif + struct wgnutls_transport_context *ctx = arg; + int ret = gnutls_record_check_pending (ctx->session); + struct st_read_timer read_timer = {(timeout == -1 ? opt.read_timeout : timeout), 0, NULL, 0}; + + if (ret) + return gnutls_record_recv (ctx->session, buf, MIN (ret, bufsize)); + + if (read_timer.timeout) + { +#ifdef F_GETFL + flags = fcntl (fd, F_GETFL, 0); + if (flags < 0) + return flags; + if (fcntl (fd, F_SETFL, flags | O_NONBLOCK)) + return -1; +#else + /* XXX: Assume it was blocking before. */ + const int one = 1; + if (ioctl (fd, FIONBIO, &one) < 0) + return -1; +#endif + + read_timer.timer = ptimer_new (); + if (read_timer.timer == NULL) + { + ret = -1; + goto timer_err; + } + read_timer.next_timeout = read_timer.timeout; + } + + ret = ctx->last_error; + do + { + if (ret == GNUTLS_E_REHANDSHAKE) + { + int err; + DEBUGP (("GnuTLS: *** REHANDSHAKE while reading\n")); + if ((err = _do_handshake (ctx->session, fd, &read_timer)) != 0) + { + ret = err; + break; + } + } +#if GNUTLS_VERSION_NUMBER >= 0x030604 + else if (ret == GNUTLS_E_REAUTH_REQUEST) + { + int err; + DEBUGP (("GnuTLS: *** re-authentication while reading\n")); + if ((err = _do_reauth (ctx->session, fd, &read_timer)) != 0) + { + ret = err; + break; + } + } +#endif + do + { + ret = gnutls_record_recv (ctx->session, buf, bufsize); + if (ret == GNUTLS_E_AGAIN && read_timer.timer) + { + int err = select_fd_nb (fd, read_timer.next_timeout, WAIT_FOR_READ); + if (err <= 0) + { + if (err == 0) + read_timer.timed_out = 1; + goto break_all; + } + if ( (read_timer.next_timeout = read_timer.timeout - ptimer_measure (read_timer.timer)) <= 0 ) + { + read_timer.timed_out = 1; + goto break_all; + } + } + } + while (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED); + } + while (ret == GNUTLS_E_REHANDSHAKE +#if GNUTLS_VERSION_NUMBER >= 0x030604 + || ret == GNUTLS_E_REAUTH_REQUEST +#endif + ); + +break_all: + if (read_timer.timer) + { + ptimer_destroy (read_timer.timer); +timer_err: ; +#ifdef F_GETFL + if (fcntl (fd, F_SETFL, flags) < 0) + return -1; +#else + { + const int zero = 0; + if (ioctl (fd, FIONBIO, &zero) < 0) + return -1; + } +#endif + if (read_timer.timed_out) + errno = ETIMEDOUT; + } + + return ret; +} + +static int +wgnutls_read (int fd, char *buf, int bufsize, void *arg, double timeout) +{ + int ret; + struct wgnutls_transport_context *ctx = arg; + + if (ctx->peeklen) + { + /* If we have any peek data, simply return that. */ + int copysize = MIN (bufsize, ctx->peeklen); + memcpy (buf, ctx->peekbuf, copysize); + ctx->peeklen -= copysize; + if (ctx->peeklen != 0) + memmove (ctx->peekbuf, ctx->peekbuf + copysize, ctx->peeklen); + + return copysize; + } + + ret = wgnutls_read_timeout (fd, buf, bufsize, arg, timeout); + ctx->last_error = ret; + return ret; +} + +static int +wgnutls_write (int fd _GL_UNUSED, char *buf, int bufsize, void *arg) +{ + struct wgnutls_transport_context *ctx = arg; + int ret = ctx->last_error; + + /* it should never happen, + placed here only for debug msg. */ + if (ret == GNUTLS_E_REHANDSHAKE) + { + DEBUGP (("GnuTLS: *** REHANDSHAKE while writing\n")); + if ((ret = _do_handshake (ctx->session, fd, NULL)) != 0) + goto ext; + } +#if GNUTLS_VERSION_NUMBER >= 0x030604 + else if (ret == GNUTLS_E_REAUTH_REQUEST) + { + DEBUGP (("GnuTLS: *** re-authentication while writing\n")); + if ((ret = _do_reauth (ctx->session, fd, NULL)) != 0) + goto ext; + } +#endif + + do + ret = gnutls_record_send (ctx->session, buf, bufsize); + while (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN); +ext: + ctx->last_error = ret; + return ret; +} + +static int +wgnutls_poll (int fd, double timeout, int wait_for, void *arg) +{ + struct wgnutls_transport_context *ctx = arg; + + if ((wait_for & WAIT_FOR_READ) + && (ctx->peeklen || gnutls_record_check_pending (ctx->session))) + return 1; + + if (timeout == -1) + timeout = opt.read_timeout; + return select_fd (fd, timeout, wait_for); +} + +static int +wgnutls_peek (int fd, char *buf, int bufsize, void *arg, double timeout) +{ + int read = 0; + struct wgnutls_transport_context *ctx = arg; + int offset = MIN (bufsize, ctx->peeklen); + + if (ctx->peeklen) + { + memcpy (buf, ctx->peekbuf, offset); + return offset; + } + + if (bufsize > (int) sizeof ctx->peekbuf) + bufsize = sizeof ctx->peekbuf; + + if (bufsize > offset) + { /* let wgnutls_read_timeout() take care about timeout */ + /*if (timeout && gnutls_record_check_pending (ctx->session) == 0 + && select_fd (fd, 0.0, WAIT_FOR_READ) <= 0) + read = 0; + else*/ + read = wgnutls_read_timeout (fd, buf + offset, bufsize - offset, + ctx, timeout); + ctx->last_error = read; + if (read < 0) + { + if (offset) + read = 0; + else + return read; + } + + if (read > 0) + { + memcpy (ctx->peekbuf + offset, buf + offset, + read); + ctx->peeklen += read; + } + } + + return offset + read; +} + +static const char * +wgnutls_errstr (int fd _GL_UNUSED, void *arg) +{ + struct wgnutls_transport_context *ctx = arg; + + if (ctx->last_error > 0 + || ((ctx->last_error == GNUTLS_E_AGAIN + || ctx->last_error == GNUTLS_E_REHANDSHAKE +#if GNUTLS_VERSION_NUMBER >= 0x030604 + || ctx->last_error == GNUTLS_E_REAUTH_REQUEST +#endif + ) && errno == ETIMEDOUT)) + return NULL; + + return gnutls_strerror (ctx->last_error); +} + +static void +wgnutls_close (int fd, void *arg) +{ + struct wgnutls_transport_context *ctx = arg; + /*gnutls_bye (ctx->session, GNUTLS_SHUT_RDWR);*/ + if (ctx->session_data) + { + gnutls_free (ctx->session_data->data); + gnutls_free (ctx->session_data); + } + gnutls_deinit (ctx->session); + xfree (ctx); + close (fd); +} + +/* gnutls_transport is the singleton that describes the SSL transport + methods provided by this file. */ + +static struct transport_implementation wgnutls_transport = +{ + wgnutls_read, wgnutls_write, wgnutls_poll, + wgnutls_peek, wgnutls_errstr, wgnutls_close +}; + +static int +_do_handshake (gnutls_session_t session, int fd, struct st_read_timer *read_timer) +{ +#ifdef F_GETFL + int flags = 0; +#endif + int err; + double next_timeout = (read_timer ? read_timer->next_timeout : opt.read_timeout); + + /* if (read_timer != NULL) - fd is already non blocking */ + if (!read_timer && next_timeout) + { +#ifdef F_GETFL + flags = fcntl (fd, F_GETFL, 0); + if (flags < 0) + return flags; + if (fcntl (fd, F_SETFL, flags | O_NONBLOCK)) + return -1; +#else + /* XXX: Assume it was blocking before. */ + const int one = 1; + if (ioctl (fd, FIONBIO, &one) < 0) + return -1; +#endif + } + + /* We don't stop the handshake process for non-fatal errors */ + do + { + err = gnutls_handshake (session); + + if (err == GNUTLS_E_AGAIN && next_timeout) + { + int sel; + if (gnutls_record_get_direction (session)) + { + /* wait for writeability */ + sel = WAIT_FOR_WRITE; + } + else + { + /* wait for readability */ + sel = WAIT_FOR_READ; + } + sel = select_fd_nb (fd, next_timeout, sel); + + if (sel <= 0) + { + if (sel == 0) + { + if (read_timer) + goto read_timedout; + else + { + errno = ETIMEDOUT; + err = -1; + } + } + break; + } + if (read_timer) + { + if ( (read_timer->next_timeout = read_timer->timeout - ptimer_measure (read_timer->timer)) <= 0 ) + { +read_timedout: /* return GNUTLS_E_REHANDSHAKE for gnutls_read */ + err = GNUTLS_E_REHANDSHAKE; + read_timer->timed_out = 1; + break; + } + next_timeout = read_timer->next_timeout; + } + } + else if (err < 0) + { + logprintf (LOG_NOTQUIET, "GnuTLS: %s\n", gnutls_strerror (err)); + if (err == GNUTLS_E_WARNING_ALERT_RECEIVED || + err == GNUTLS_E_FATAL_ALERT_RECEIVED) + { + gnutls_alert_description_t alert = gnutls_alert_get (session); + const char *str = gnutls_alert_get_name (alert); + logprintf (LOG_NOTQUIET, "GnuTLS: received alert [%u]: %s\n", + alert, str ? str : "(unknown)"); + } + } + } + while (err && gnutls_error_is_fatal (err) == 0); + + if (!read_timer && next_timeout) + { +#ifdef F_GETFL + if (fcntl (fd, F_SETFL, flags) < 0) + return -1; +#else + const int zero = 0; + if (ioctl (fd, FIONBIO, &zero) < 0) + return -1; +#endif + } + + return err; +} + +#if GNUTLS_VERSION_NUMBER >= 0x030604 +static int +_do_reauth (gnutls_session_t session, int fd, struct st_read_timer *read_timer) +{ +#ifdef F_GETFL + int flags = 0; +#endif + int err; + double next_timeout = (read_timer ? read_timer->next_timeout : opt.read_timeout); + + /* if (read_timer != NULL) - fd is already non blocking */ + if (!read_timer && next_timeout) + { +#ifdef F_GETFL + flags = fcntl (fd, F_GETFL, 0); + if (flags < 0) + return flags; + if (fcntl (fd, F_SETFL, flags | O_NONBLOCK)) + return -1; +#else + /* XXX: Assume it was blocking before. */ + const int one = 1; + if (ioctl (fd, FIONBIO, &one) < 0) + return -1; +#endif + } + + /* We don't stop the handshake process for non-fatal errors */ + do + { + err = gnutls_reauth (session, 0); + + if (err == GNUTLS_E_AGAIN && next_timeout) + { + int sel; + if (gnutls_record_get_direction (session)) + { + /* wait for writeability */ + sel = WAIT_FOR_WRITE; + } + else + { + /* wait for readability */ + sel = WAIT_FOR_READ; + } + sel = select_fd_nb (fd, next_timeout, sel); + + if (sel <= 0) + { + if (sel == 0) + { + if (read_timer) + goto read_timedout; + else + { + errno = ETIMEDOUT; + err = -1; + } + } + break; + } + if (read_timer) + { + if ( (read_timer->next_timeout = read_timer->timeout - ptimer_measure (read_timer->timer)) <= 0 ) + { +read_timedout: /* return GNUTLS_E_REAUTH_REQUEST for gnutls_read */ + err = GNUTLS_E_REAUTH_REQUEST; + read_timer->timed_out = 1; + break; + } + next_timeout = read_timer->next_timeout; + } + } + else if (err < 0) + { + logprintf (LOG_NOTQUIET, "GnuTLS: %s\n", gnutls_strerror (err)); + } + } + while (err && gnutls_error_is_fatal (err) == 0); + + if (!read_timer && next_timeout) + { +#ifdef F_GETFL + if (fcntl (fd, F_SETFL, flags) < 0) + return -1; +#else + const int zero = 0; + if (ioctl (fd, FIONBIO, &zero) < 0) + return -1; +#endif + } + + return err; +} +#endif + +static const char * +_sni_hostname(const char *hostname) +{ + size_t len = strlen(hostname); + + char *sni_hostname = xmemdup(hostname, len + 1); + + /* Remove trailing dot(s) to fix #47408. + * Regarding RFC 6066 (SNI): The hostname is represented as a byte + * string using ASCII encoding without a trailing dot. */ + while (len && sni_hostname[--len] == '.') + sni_hostname[len] = 0; + + return sni_hostname; +} + +static int +set_prio_default (gnutls_session_t session) +{ + int err = -1; + +#if HAVE_GNUTLS_PRIORITY_SET_DIRECT + switch (opt.secure_protocol) + { + case secure_protocol_auto: + err = gnutls_set_default_priority (session); + gnutls_session_enable_compatibility_mode(session); + break; + + case secure_protocol_sslv2: + case secure_protocol_sslv3: + err = gnutls_priority_set_direct (session, "NORMAL:-VERS-TLS-ALL:+VERS-SSL3.0", NULL); + break; + + case secure_protocol_tlsv1: + err = gnutls_priority_set_direct (session, "NORMAL:-VERS-SSL3.0", NULL); + break; + + case secure_protocol_tlsv1_1: + err = gnutls_priority_set_direct (session, "NORMAL:-VERS-SSL3.0:-VERS-TLS1.0", NULL); + break; + + case secure_protocol_tlsv1_2: + err = gnutls_priority_set_direct (session, "NORMAL:-VERS-SSL3.0:-VERS-TLS1.0:-VERS-TLS1.1", NULL); + break; + + case secure_protocol_tlsv1_3: +#if GNUTLS_VERSION_NUMBER >= 0x030603 + err = gnutls_priority_set_direct (session, "NORMAL:-VERS-SSL3.0:+VERS-TLS1.3:-VERS-TLS1.0:-VERS-TLS1.1:-VERS-TLS1.2", NULL); + break; +#else + logprintf (LOG_NOTQUIET, _("Your GnuTLS version is too old to support TLS 1.3\n")); + return -1; +#endif + + case secure_protocol_pfs: + err = gnutls_priority_set_direct (session, "PFS:-VERS-SSL3.0", NULL); + if (err != GNUTLS_E_SUCCESS) + /* fallback if PFS is not available */ + err = gnutls_priority_set_direct (session, "NORMAL:-RSA:-VERS-SSL3.0", NULL); + break; + + default: + logprintf (LOG_NOTQUIET, _("GnuTLS: unimplemented 'secure-protocol' option value %u\n"), + (unsigned) opt.secure_protocol); + logprintf (LOG_NOTQUIET, _("Please report this issue to bug-wget@gnu.org\n")); + abort (); + } +#else + int allowed_protocols[4] = {0, 0, 0, 0}; + switch (opt.secure_protocol) + { + case secure_protocol_auto: + err = gnutls_set_default_priority (session); + break; + + case secure_protocol_sslv2: + case secure_protocol_sslv3: + allowed_protocols[0] = GNUTLS_SSL3; + err = gnutls_protocol_set_priority (session, allowed_protocols); + break; + + case secure_protocol_tlsv1: + allowed_protocols[0] = GNUTLS_TLS1_0; + allowed_protocols[1] = GNUTLS_TLS1_1; + allowed_protocols[2] = GNUTLS_TLS1_2; +#if GNUTLS_VERSION_NUMBER >= 0x030603 + allowed_protocols[3] = GNUTLS_TLS1_3; +#endif + err = gnutls_protocol_set_priority (session, allowed_protocols); + break; + + case secure_protocol_tlsv1_1: + allowed_protocols[0] = GNUTLS_TLS1_1; + allowed_protocols[1] = GNUTLS_TLS1_2; +#if GNUTLS_VERSION_NUMBER >= 0x030603 + allowed_protocols[2] = GNUTLS_TLS1_3; +#endif + err = gnutls_protocol_set_priority (session, allowed_protocols); + break; + + case secure_protocol_tlsv1_2: + allowed_protocols[0] = GNUTLS_TLS1_2; +#if GNUTLS_VERSION_NUMBER >= 0x030603 + allowed_protocols[1] = GNUTLS_TLS1_3; +#endif + err = gnutls_protocol_set_priority (session, allowed_protocols); + break; + + case secure_protocol_tlsv1_3: +#if GNUTLS_VERSION_NUMBER >= 0x030603 + allowed_protocols[0] = GNUTLS_TLS1_3; + err = gnutls_protocol_set_priority (session, allowed_protocols); + break; +#else + logprintf (LOG_NOTQUIET, _("Your GnuTLS version is too old to support TLS 1.3\n")); + return -1; +#endif + + default: + logprintf (LOG_NOTQUIET, _("GnuTLS: unimplemented 'secure-protocol' option value %d\n"), opt.secure_protocol); + logprintf (LOG_NOTQUIET, _("Please report this issue to bug-wget@gnu.org\n")); + abort (); + } +#endif + + return err; +} + +bool +ssl_connect_wget (int fd, const char *hostname, int *continue_session) +{ + struct wgnutls_transport_context *ctx; + gnutls_session_t session; + int err; + +#if GNUTLS_VERSION_NUMBER >= 0x030604 + // enable support of TLS1.3 post-handshake authentication + gnutls_init (&session, GNUTLS_CLIENT | GNUTLS_POST_HANDSHAKE_AUTH); +#else + gnutls_init (&session, GNUTLS_CLIENT); +#endif + + /* We set the server name but only if it's not an IP address. */ + if (! is_valid_ip_address (hostname)) + { + /* GnuTLS 3.4.x (x<=10) disrespects the length parameter, we have to construct a new string */ + /* see https://gitlab.com/gnutls/gnutls/issues/78 */ + const char *sni_hostname = _sni_hostname(hostname); + + gnutls_server_name_set (session, GNUTLS_NAME_DNS, sni_hostname, strlen(sni_hostname)); + xfree(sni_hostname); + } + + gnutls_credentials_set (session, GNUTLS_CRD_CERTIFICATE, credentials); +#ifndef FD_TO_SOCKET +# define FD_TO_SOCKET(X) (X) +#endif +#ifdef HAVE_INTPTR_T + gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) (intptr_t) FD_TO_SOCKET (fd)); +#else + gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) FD_TO_SOCKET (fd)); +#endif + + if (!opt.tls_ciphers_string) + { + err = set_prio_default (session); + } + else + { +#if HAVE_GNUTLS_PRIORITY_SET_DIRECT + err = gnutls_priority_set_direct (session, opt.tls_ciphers_string, NULL); +#else + logprintf (LOG_NOTQUIET, _("GnuTLS: Cannot set prio string directly. Falling back to default priority.\n")); + err = gnutls_set_default_priority (session); +#endif + } + + if (err < 0) + { + logprintf (LOG_NOTQUIET, "GnuTLS: %s\n", gnutls_strerror (err)); + gnutls_deinit (session); + return false; + } + + if (continue_session) + { + ctx = (struct wgnutls_transport_context *) fd_transport_context (*continue_session); + if (!gnutls_session_is_resumed (session)) + { + if (!ctx || !ctx->session_data || gnutls_session_set_data (session, ctx->session_data->data, ctx->session_data->size)) + { + if (ctx && ctx->session_data) + { + /* server does not want to continue the session */ + if (ctx->session_data->data) + gnutls_free (ctx->session_data->data); + gnutls_free (ctx->session_data); + } + gnutls_deinit (session); + return false; + } + } + else + { + logputs (LOG_ALWAYS, "SSL session has already been resumed. Continuing.\n"); + continue_session = NULL; + } + } + + err = _do_handshake (session, fd, NULL); + + if (err < 0) + { + gnutls_deinit (session); + return false; + } + + ctx = xnew0 (struct wgnutls_transport_context); + ctx->session_data = xnew0 (gnutls_datum_t); + ctx->session = session; + if (gnutls_session_get_data2 (session, ctx->session_data)) + { + xfree (ctx->session_data); + logprintf (LOG_NOTQUIET, "WARNING: Could not save SSL session data for socket %d\n", fd); + } + fd_register_transport (fd, &wgnutls_transport, ctx); + return true; +} + +static bool +pkp_pin_peer_pubkey (gnutls_x509_crt_t cert, const char *pinnedpubkey) +{ + /* Scratch */ + size_t len1 = 0, len2 = 0; + char *buff1 = NULL; + + gnutls_pubkey_t key = NULL; + + /* Result is returned to caller */ + int ret = 0; + bool result = false; + + /* if a path wasn't specified, don't pin */ + if (NULL == pinnedpubkey) + return true; + + if (NULL == cert) + return result; + + /* Begin Gyrations to get the public key */ + gnutls_pubkey_init (&key); + + ret = gnutls_pubkey_import_x509 (key, cert, 0); + if (ret < 0) + goto cleanup; /* failed */ + + ret = gnutls_pubkey_export (key, GNUTLS_X509_FMT_DER, NULL, &len1); + if (ret != GNUTLS_E_SHORT_MEMORY_BUFFER || len1 == 0) + goto cleanup; /* failed */ + + buff1 = xmalloc (len1); + + len2 = len1; + + ret = gnutls_pubkey_export (key, GNUTLS_X509_FMT_DER, buff1, &len2); + if (ret < 0 || len1 != len2) + goto cleanup; /* failed */ + + /* End Gyrations */ + + /* The one good exit point */ + result = wg_pin_peer_pubkey (pinnedpubkey, buff1, len1); + + cleanup: + if (NULL != key) + gnutls_pubkey_deinit (key); + + xfree (buff1); + + return result; +} + +#define _CHECK_CERT(flag,msg) \ + if (status & (flag))\ + {\ + logprintf (LOG_NOTQUIET, (msg),\ + severity, quote (host));\ + success = false;\ + } + +bool +ssl_check_certificate (int fd, const char *host) +{ + struct wgnutls_transport_context *ctx = fd_transport_context (fd); + + unsigned int status; + int err; + + /* If the user has specified --no-check-cert, we still want to warn + him about problems with the server's certificate. */ + const char *severity = opt.check_cert ? _("ERROR") : _("WARNING"); + bool success = true; + bool pinsuccess = opt.pinnedpubkey == NULL; + + /* The user explicitly said to not check for the certificate. */ + if (opt.check_cert == CHECK_CERT_QUIET && pinsuccess) + return success; + + err = gnutls_certificate_verify_peers2 (ctx->session, &status); + if (err < 0) + { + logprintf (LOG_NOTQUIET, _("%s: No certificate presented by %s.\n"), + severity, quotearg_style (escape_quoting_style, host)); + success = false; + goto out; + } + + _CHECK_CERT (GNUTLS_CERT_INVALID, _("%s: The certificate of %s is not trusted.\n")); + _CHECK_CERT (GNUTLS_CERT_SIGNER_NOT_FOUND, _("%s: The certificate of %s doesn't have a known issuer.\n")); + _CHECK_CERT (GNUTLS_CERT_REVOKED, _("%s: The certificate of %s has been revoked.\n")); + _CHECK_CERT (GNUTLS_CERT_SIGNER_NOT_CA, _("%s: The certificate signer of %s was not a CA.\n")); + _CHECK_CERT (GNUTLS_CERT_INSECURE_ALGORITHM, _("%s: The certificate of %s was signed using an insecure algorithm.\n")); + _CHECK_CERT (GNUTLS_CERT_NOT_ACTIVATED, _("%s: The certificate of %s is not yet activated.\n")); + _CHECK_CERT (GNUTLS_CERT_EXPIRED, _("%s: The certificate of %s has expired.\n")); + + if (gnutls_certificate_type_get (ctx->session) == GNUTLS_CRT_X509) + { + time_t now = time (NULL); + gnutls_x509_crt_t cert; + const gnutls_datum_t *cert_list; + unsigned int cert_list_size; + const char *sni_hostname; + + if ((err = gnutls_x509_crt_init (&cert)) < 0) + { + logprintf (LOG_NOTQUIET, _("Error initializing X509 certificate: %s\n"), + gnutls_strerror (err)); + success = false; + goto out; + } + + cert_list = gnutls_certificate_get_peers (ctx->session, &cert_list_size); + if (!cert_list) + { + logprintf (LOG_NOTQUIET, _("No certificate found\n")); + success = false; + goto crt_deinit; + } + err = gnutls_x509_crt_import (cert, cert_list, GNUTLS_X509_FMT_DER); + if (err < 0) + { + logprintf (LOG_NOTQUIET, _("Error parsing certificate: %s\n"), + gnutls_strerror (err)); + success = false; + goto crt_deinit; + } + if (now < gnutls_x509_crt_get_activation_time (cert)) + { + logprintf (LOG_NOTQUIET, _("The certificate has not yet been activated\n")); + success = false; + } + if (now >= gnutls_x509_crt_get_expiration_time (cert)) + { + logprintf (LOG_NOTQUIET, _("The certificate has expired\n")); + success = false; + } + sni_hostname = _sni_hostname(host); + if (!gnutls_x509_crt_check_hostname (cert, sni_hostname)) + { + logprintf (LOG_NOTQUIET, + _("The certificate's owner does not match hostname %s\n"), + quote (sni_hostname)); + success = false; + } + xfree(sni_hostname); + + pinsuccess = pkp_pin_peer_pubkey (cert, opt.pinnedpubkey); + if (!pinsuccess) + { + logprintf (LOG_ALWAYS, _("The public key does not match pinned public key!\n")); + success = false; + } + + crt_deinit: + gnutls_x509_crt_deinit (cert); + } + else + { + logprintf (LOG_NOTQUIET, _("Certificate must be X.509\n")); + success = false; + } + + out: + /* never return true if pinsuccess fails */ + return !pinsuccess ? false : (opt.check_cert == CHECK_CERT_ON ? success : true); +} |