diff options
Diffstat (limited to 'source4/lib/tls/tls.c')
| -rw-r--r-- | source4/lib/tls/tls.c | 690 |
1 files changed, 690 insertions, 0 deletions
diff --git a/source4/lib/tls/tls.c b/source4/lib/tls/tls.c new file mode 100644 index 0000000000..b298fb10cf --- /dev/null +++ b/source4/lib/tls/tls.c @@ -0,0 +1,690 @@ +/* + Unix SMB/CIFS implementation. + + transport layer security handling code + + Copyright (C) Andrew Tridgell 2004-2005 + Copyright (C) Stefan Metzmacher 2004 + Copyright (C) Andrew Bartlett 2006 + + This program 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. + + 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +#include "includes.h" +#include "lib/events/events.h" +#include "lib/socket/socket.h" +#include "lib/tls/tls.h" +#include "param/param.h" + +#if ENABLE_GNUTLS +#include "gnutls/gnutls.h" + +#define DH_BITS 1024 + +#if defined(HAVE_GNUTLS_DATUM) && !defined(HAVE_GNUTLS_DATUM_T) +typedef gnutls_datum gnutls_datum_t; +#endif + +/* hold persistent tls data */ +struct tls_params { + gnutls_certificate_credentials x509_cred; + gnutls_dh_params dh_params; + bool tls_enabled; +}; +#endif + +/* hold per connection tls data */ +struct tls_context { + struct socket_context *socket; + struct fd_event *fde; + bool tls_enabled; +#if ENABLE_GNUTLS + gnutls_session session; + bool done_handshake; + bool have_first_byte; + uint8_t first_byte; + bool tls_detect; + const char *plain_chars; + bool output_pending; + gnutls_certificate_credentials xcred; + bool interrupted; +#endif +}; + +bool tls_enabled(struct socket_context *sock) +{ + struct tls_context *tls; + if (!sock) { + return false; + } + if (strcmp(sock->backend_name, "tls") != 0) { + return false; + } + tls = talloc_get_type(sock->private_data, struct tls_context); + if (!tls) { + return false; + } + return tls->tls_enabled; +} + + +#if ENABLE_GNUTLS + +static const struct socket_ops tls_socket_ops; + +static NTSTATUS tls_socket_init(struct socket_context *sock) +{ + switch (sock->type) { + case SOCKET_TYPE_STREAM: + break; + default: + return NT_STATUS_INVALID_PARAMETER; + } + + sock->backend_name = "tls"; + + return NT_STATUS_OK; +} + +#define TLSCHECK(call) do { \ + ret = call; \ + if (ret < 0) { \ + DEBUG(0,("TLS %s - %s\n", #call, gnutls_strerror(ret))); \ + goto failed; \ + } \ +} while (0) + + +/* + callback for reading from a socket +*/ +static ssize_t tls_pull(gnutls_transport_ptr ptr, void *buf, size_t size) +{ + struct tls_context *tls = talloc_get_type(ptr, struct tls_context); + NTSTATUS status; + size_t nread; + + if (tls->have_first_byte) { + *(uint8_t *)buf = tls->first_byte; + tls->have_first_byte = false; + return 1; + } + + status = socket_recv(tls->socket, buf, size, &nread); + if (NT_STATUS_EQUAL(status, NT_STATUS_END_OF_FILE)) { + return 0; + } + if (NT_STATUS_IS_ERR(status)) { + EVENT_FD_NOT_READABLE(tls->fde); + EVENT_FD_NOT_WRITEABLE(tls->fde); + errno = EBADF; + return -1; + } + if (!NT_STATUS_IS_OK(status)) { + EVENT_FD_READABLE(tls->fde); + errno = EAGAIN; + return -1; + } + if (tls->output_pending) { + EVENT_FD_WRITEABLE(tls->fde); + } + if (size != nread) { + EVENT_FD_READABLE(tls->fde); + } + return nread; +} + +/* + callback for writing to a socket +*/ +static ssize_t tls_push(gnutls_transport_ptr ptr, const void *buf, size_t size) +{ + struct tls_context *tls = talloc_get_type(ptr, struct tls_context); + NTSTATUS status; + size_t nwritten; + DATA_BLOB b; + + if (!tls->tls_enabled) { + return size; + } + + b.data = discard_const(buf); + b.length = size; + + status = socket_send(tls->socket, &b, &nwritten); + if (NT_STATUS_EQUAL(status, STATUS_MORE_ENTRIES)) { + errno = EAGAIN; + return -1; + } + if (!NT_STATUS_IS_OK(status)) { + EVENT_FD_WRITEABLE(tls->fde); + return -1; + } + if (size != nwritten) { + EVENT_FD_WRITEABLE(tls->fde); + } + return nwritten; +} + +/* + destroy a tls session + */ +static int tls_destructor(struct tls_context *tls) +{ + int ret; + ret = gnutls_bye(tls->session, GNUTLS_SHUT_WR); + if (ret < 0) { + DEBUG(0,("TLS gnutls_bye failed - %s\n", gnutls_strerror(ret))); + } + return 0; +} + + +/* + possibly continue the handshake process +*/ +static NTSTATUS tls_handshake(struct tls_context *tls) +{ + int ret; + + if (tls->done_handshake) { + return NT_STATUS_OK; + } + + ret = gnutls_handshake(tls->session); + if (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN) { + if (gnutls_record_get_direction(tls->session) == 1) { + EVENT_FD_WRITEABLE(tls->fde); + } + return STATUS_MORE_ENTRIES; + } + if (ret < 0) { + DEBUG(0,("TLS gnutls_handshake failed - %s\n", gnutls_strerror(ret))); + return NT_STATUS_UNEXPECTED_NETWORK_ERROR; + } + tls->done_handshake = true; + return NT_STATUS_OK; +} + +/* + possibly continue an interrupted operation +*/ +static NTSTATUS tls_interrupted(struct tls_context *tls) +{ + int ret; + + if (!tls->interrupted) { + return NT_STATUS_OK; + } + if (gnutls_record_get_direction(tls->session) == 1) { + ret = gnutls_record_send(tls->session, NULL, 0); + } else { + ret = gnutls_record_recv(tls->session, NULL, 0); + } + if (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN) { + return STATUS_MORE_ENTRIES; + } + tls->interrupted = false; + return NT_STATUS_OK; +} + +/* + see how many bytes are pending on the connection +*/ +static NTSTATUS tls_socket_pending(struct socket_context *sock, size_t *npending) +{ + struct tls_context *tls = talloc_get_type(sock->private_data, struct tls_context); + if (!tls->tls_enabled || tls->tls_detect) { + return socket_pending(tls->socket, npending); + } + *npending = gnutls_record_check_pending(tls->session); + if (*npending == 0) { + NTSTATUS status = socket_pending(tls->socket, npending); + if (*npending == 0) { + /* seems to be a gnutls bug */ + (*npending) = 100; + } + return status; + } + return NT_STATUS_OK; +} + +/* + receive data either by tls or normal socket_recv +*/ +static NTSTATUS tls_socket_recv(struct socket_context *sock, void *buf, + size_t wantlen, size_t *nread) +{ + int ret; + NTSTATUS status; + struct tls_context *tls = talloc_get_type(sock->private_data, struct tls_context); + + if (tls->tls_enabled && tls->tls_detect) { + status = socket_recv(tls->socket, &tls->first_byte, 1, nread); + NT_STATUS_NOT_OK_RETURN(status); + if (*nread == 0) return NT_STATUS_OK; + tls->tls_detect = false; + /* look for the first byte of a valid HTTP operation */ + if (strchr(tls->plain_chars, tls->first_byte)) { + /* not a tls link */ + tls->tls_enabled = false; + *(uint8_t *)buf = tls->first_byte; + return NT_STATUS_OK; + } + tls->have_first_byte = true; + } + + if (!tls->tls_enabled) { + return socket_recv(tls->socket, buf, wantlen, nread); + } + + status = tls_handshake(tls); + NT_STATUS_NOT_OK_RETURN(status); + + status = tls_interrupted(tls); + NT_STATUS_NOT_OK_RETURN(status); + + ret = gnutls_record_recv(tls->session, buf, wantlen); + if (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN) { + if (gnutls_record_get_direction(tls->session) == 1) { + EVENT_FD_WRITEABLE(tls->fde); + } + tls->interrupted = true; + return STATUS_MORE_ENTRIES; + } + if (ret < 0) { + return NT_STATUS_UNEXPECTED_NETWORK_ERROR; + } + *nread = ret; + return NT_STATUS_OK; +} + + +/* + send data either by tls or normal socket_recv +*/ +static NTSTATUS tls_socket_send(struct socket_context *sock, + const DATA_BLOB *blob, size_t *sendlen) +{ + NTSTATUS status; + int ret; + struct tls_context *tls = talloc_get_type(sock->private_data, struct tls_context); + + if (!tls->tls_enabled) { + return socket_send(tls->socket, blob, sendlen); + } + + status = tls_handshake(tls); + NT_STATUS_NOT_OK_RETURN(status); + + status = tls_interrupted(tls); + NT_STATUS_NOT_OK_RETURN(status); + + ret = gnutls_record_send(tls->session, blob->data, blob->length); + if (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN) { + if (gnutls_record_get_direction(tls->session) == 1) { + EVENT_FD_WRITEABLE(tls->fde); + } + tls->interrupted = true; + return STATUS_MORE_ENTRIES; + } + if (ret < 0) { + DEBUG(0,("gnutls_record_send of %d failed - %s\n", (int)blob->length, gnutls_strerror(ret))); + return NT_STATUS_UNEXPECTED_NETWORK_ERROR; + } + *sendlen = ret; + tls->output_pending = (ret < blob->length); + return NT_STATUS_OK; +} + + +/* + initialise global tls state +*/ +struct tls_params *tls_initialise(TALLOC_CTX *mem_ctx, struct loadparm_context *lp_ctx) +{ + struct tls_params *params; + int ret; + TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx); + const char *keyfile = private_path(tmp_ctx, lp_ctx, lp_tls_keyfile(lp_ctx)); + const char *certfile = private_path(tmp_ctx, lp_ctx, lp_tls_certfile(lp_ctx)); + const char *cafile = private_path(tmp_ctx, lp_ctx, lp_tls_cafile(lp_ctx)); + const char *crlfile = private_path(tmp_ctx, lp_ctx, lp_tls_crlfile(lp_ctx)); + const char *dhpfile = private_path(tmp_ctx, lp_ctx, lp_tls_dhpfile(lp_ctx)); + void tls_cert_generate(TALLOC_CTX *, const char *, const char *, const char *); + + params = talloc(mem_ctx, struct tls_params); + if (params == NULL) { + talloc_free(tmp_ctx); + return NULL; + } + + if (!lp_tls_enabled(lp_ctx) || keyfile == NULL || *keyfile == 0) { + params->tls_enabled = false; + talloc_free(tmp_ctx); + return params; + } + + if (!file_exist(cafile)) { + tls_cert_generate(params, keyfile, certfile, cafile); + } + + ret = gnutls_global_init(); + if (ret < 0) goto init_failed; + + gnutls_certificate_allocate_credentials(¶ms->x509_cred); + if (ret < 0) goto init_failed; + + if (cafile && *cafile) { + ret = gnutls_certificate_set_x509_trust_file(params->x509_cred, cafile, + GNUTLS_X509_FMT_PEM); + if (ret < 0) { + DEBUG(0,("TLS failed to initialise cafile %s\n", cafile)); + goto init_failed; + } + } + + if (crlfile && *crlfile) { + ret = gnutls_certificate_set_x509_crl_file(params->x509_cred, + crlfile, + GNUTLS_X509_FMT_PEM); + if (ret < 0) { + DEBUG(0,("TLS failed to initialise crlfile %s\n", crlfile)); + goto init_failed; + } + } + + ret = gnutls_certificate_set_x509_key_file(params->x509_cred, + certfile, keyfile, + GNUTLS_X509_FMT_PEM); + if (ret < 0) { + DEBUG(0,("TLS failed to initialise certfile %s and keyfile %s\n", + certfile, keyfile)); + goto init_failed; + } + + + ret = gnutls_dh_params_init(¶ms->dh_params); + if (ret < 0) goto init_failed; + + if (dhpfile && *dhpfile) { + gnutls_datum_t dhparms; + size_t size; + dhparms.data = (uint8_t *)file_load(dhpfile, &size, mem_ctx); + + if (!dhparms.data) { + DEBUG(0,("Failed to read DH Parms from %s\n", dhpfile)); + goto init_failed; + } + dhparms.size = size; + + ret = gnutls_dh_params_import_pkcs3(params->dh_params, &dhparms, GNUTLS_X509_FMT_PEM); + if (ret < 0) goto init_failed; + } else { + ret = gnutls_dh_params_generate2(params->dh_params, DH_BITS); + if (ret < 0) goto init_failed; + } + + gnutls_certificate_set_dh_params(params->x509_cred, params->dh_params); + + params->tls_enabled = true; + + talloc_free(tmp_ctx); + return params; + +init_failed: + DEBUG(0,("GNUTLS failed to initialise - %s\n", gnutls_strerror(ret))); + params->tls_enabled = false; + talloc_free(tmp_ctx); + return params; +} + + +/* + setup for a new connection +*/ +struct socket_context *tls_init_server(struct tls_params *params, + struct socket_context *socket, + struct fd_event *fde, + const char *plain_chars) +{ + struct tls_context *tls; + int ret; + struct socket_context *new_sock; + NTSTATUS nt_status; + + nt_status = socket_create_with_ops(socket, &tls_socket_ops, &new_sock, + SOCKET_TYPE_STREAM, + socket->flags | SOCKET_FLAG_ENCRYPT); + if (!NT_STATUS_IS_OK(nt_status)) { + return NULL; + } + + tls = talloc(new_sock, struct tls_context); + if (tls == NULL) { + return NULL; + } + + tls->socket = socket; + tls->fde = fde; + if (talloc_reference(tls, fde) == NULL) { + talloc_free(new_sock); + return NULL; + } + if (talloc_reference(tls, socket) == NULL) { + talloc_free(new_sock); + return NULL; + } + + new_sock->private_data = tls; + + if (!params->tls_enabled) { + talloc_free(new_sock); + return NULL; + } + + TLSCHECK(gnutls_init(&tls->session, GNUTLS_SERVER)); + + talloc_set_destructor(tls, tls_destructor); + + TLSCHECK(gnutls_set_default_priority(tls->session)); + TLSCHECK(gnutls_credentials_set(tls->session, GNUTLS_CRD_CERTIFICATE, + params->x509_cred)); + gnutls_certificate_server_set_request(tls->session, GNUTLS_CERT_REQUEST); + gnutls_dh_set_prime_bits(tls->session, DH_BITS); + gnutls_transport_set_ptr(tls->session, (gnutls_transport_ptr)tls); + gnutls_transport_set_pull_function(tls->session, (gnutls_pull_func)tls_pull); + gnutls_transport_set_push_function(tls->session, (gnutls_push_func)tls_push); + gnutls_transport_set_lowat(tls->session, 0); + + tls->plain_chars = plain_chars; + if (plain_chars) { + tls->tls_detect = true; + } else { + tls->tls_detect = false; + } + + tls->output_pending = false; + tls->done_handshake = false; + tls->have_first_byte = false; + tls->tls_enabled = true; + tls->interrupted = false; + + new_sock->state = SOCKET_STATE_SERVER_CONNECTED; + + return new_sock; + +failed: + DEBUG(0,("TLS init connection failed - %s\n", gnutls_strerror(ret))); + talloc_free(new_sock); + return NULL; +} + + +/* + setup for a new client connection +*/ +struct socket_context *tls_init_client(struct socket_context *socket, + struct fd_event *fde, + const char *ca_path) +{ + struct tls_context *tls; + int ret = 0; + const int cert_type_priority[] = { GNUTLS_CRT_X509, GNUTLS_CRT_OPENPGP, 0 }; + char *cafile; + struct socket_context *new_sock; + NTSTATUS nt_status; + + nt_status = socket_create_with_ops(socket, &tls_socket_ops, &new_sock, + SOCKET_TYPE_STREAM, + socket->flags | SOCKET_FLAG_ENCRYPT); + if (!NT_STATUS_IS_OK(nt_status)) { + return NULL; + } + + tls = talloc(new_sock, struct tls_context); + if (tls == NULL) return NULL; + + tls->socket = socket; + tls->fde = fde; + if (talloc_reference(tls, fde) == NULL) { + return NULL; + } + if (talloc_reference(tls, socket) == NULL) { + return NULL; + } + new_sock->private_data = tls; + + gnutls_global_init(); + + gnutls_certificate_allocate_credentials(&tls->xcred); + gnutls_certificate_set_x509_trust_file(tls->xcred, cafile, GNUTLS_X509_FMT_PEM); + TLSCHECK(gnutls_init(&tls->session, GNUTLS_CLIENT)); + TLSCHECK(gnutls_set_default_priority(tls->session)); + gnutls_certificate_type_set_priority(tls->session, cert_type_priority); + TLSCHECK(gnutls_credentials_set(tls->session, GNUTLS_CRD_CERTIFICATE, tls->xcred)); + + talloc_set_destructor(tls, tls_destructor); + + gnutls_transport_set_ptr(tls->session, (gnutls_transport_ptr)tls); + gnutls_transport_set_pull_function(tls->session, (gnutls_pull_func)tls_pull); + gnutls_transport_set_push_function(tls->session, (gnutls_push_func)tls_push); + gnutls_transport_set_lowat(tls->session, 0); + tls->tls_detect = false; + + tls->output_pending = false; + tls->done_handshake = false; + tls->have_first_byte = false; + tls->tls_enabled = true; + tls->interrupted = false; + + new_sock->state = SOCKET_STATE_CLIENT_CONNECTED; + + return new_sock; + +failed: + DEBUG(0,("TLS init connection failed - %s\n", gnutls_strerror(ret))); + tls->tls_enabled = false; + return new_sock; +} + +static NTSTATUS tls_socket_set_option(struct socket_context *sock, const char *option, const char *val) +{ + set_socket_options(socket_get_fd(sock), option); + return NT_STATUS_OK; +} + +static char *tls_socket_get_peer_name(struct socket_context *sock, TALLOC_CTX *mem_ctx) +{ + struct tls_context *tls = talloc_get_type(sock->private_data, struct tls_context); + return socket_get_peer_name(tls->socket, mem_ctx); +} + +static struct socket_address *tls_socket_get_peer_addr(struct socket_context *sock, TALLOC_CTX *mem_ctx) +{ + struct tls_context *tls = talloc_get_type(sock->private_data, struct tls_context); + return socket_get_peer_addr(tls->socket, mem_ctx); +} + +static struct socket_address *tls_socket_get_my_addr(struct socket_context *sock, TALLOC_CTX *mem_ctx) +{ + struct tls_context *tls = talloc_get_type(sock->private_data, struct tls_context); + return socket_get_my_addr(tls->socket, mem_ctx); +} + +static int tls_socket_get_fd(struct socket_context *sock) +{ + struct tls_context *tls = talloc_get_type(sock->private_data, struct tls_context); + return socket_get_fd(tls->socket); +} + +static const struct socket_ops tls_socket_ops = { + .name = "tls", + .fn_init = tls_socket_init, + .fn_recv = tls_socket_recv, + .fn_send = tls_socket_send, + .fn_pending = tls_socket_pending, + + .fn_set_option = tls_socket_set_option, + + .fn_get_peer_name = tls_socket_get_peer_name, + .fn_get_peer_addr = tls_socket_get_peer_addr, + .fn_get_my_addr = tls_socket_get_my_addr, + .fn_get_fd = tls_socket_get_fd +}; + +bool tls_support(struct tls_params *params) +{ + return params->tls_enabled; +} + +#else + +/* for systems without tls we just fail the operations, and the caller + * will retain the original socket */ + +struct tls_params *tls_initialise(TALLOC_CTX *mem_ctx, struct loadparm_context *lp_ctx) +{ + return talloc_new(mem_ctx); +} + +/* + setup for a new connection +*/ +struct socket_context *tls_init_server(struct tls_params *params, + struct socket_context *socket, + struct fd_event *fde, + const char *plain_chars) +{ + return NULL; +} + + +/* + setup for a new client connection +*/ +struct socket_context *tls_init_client(struct socket_context *socket, + struct fd_event *fde, + const char *ca_path) +{ + return NULL; +} + +bool tls_support(struct tls_params *params) +{ + return false; +} + +#endif + |