diff options
Diffstat (limited to 'source4/lib/tls/tls.c')
| -rw-r--r-- | source4/lib/tls/tls.c | 420 |
1 files changed, 420 insertions, 0 deletions
diff --git a/source4/lib/tls/tls.c b/source4/lib/tls/tls.c new file mode 100644 index 0000000000..3b166b27a0 --- /dev/null +++ b/source4/lib/tls/tls.c @@ -0,0 +1,420 @@ +/* + Unix SMB/CIFS implementation. + + transport layer security handling code + + Copyright (C) Andrew Tridgell 2005 + + 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 2 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, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. +*/ + +#include "includes.h" +#include "lib/events/events.h" +#include "lib/socket/socket.h" +#include "lib/tls/tls.h" + +#if HAVE_LIBGNUTLS +#include "gnutls/gnutls.h" + +#define DH_BITS 1024 + +/* hold persistent tls data */ +struct tls_params { + gnutls_certificate_credentials x509_cred; + gnutls_dh_params dh_params; + BOOL tls_enabled; +}; + +/* hold per connection tls data */ +struct tls_context { + struct tls_params *params; + struct socket_context *socket; + struct fd_event *fde; + gnutls_session session; + BOOL done_handshake; + BOOL have_first_byte; + uint8_t first_byte; + BOOL tls_enabled; + BOOL tls_detect; + const char *plain_chars; + BOOL output_pending; +}; + + +/* + 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, 0); + if (!NT_STATUS_IS_OK(status)) { + EVENT_FD_READABLE(tls->fde); + EVENT_FD_NOT_WRITEABLE(tls->fde); + 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, 0); + 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(void *ptr) +{ + struct tls_context *tls = talloc_get_type(ptr, struct tls_context); + 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) { + 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; +} + + +/* + receive data either by tls or normal socket_recv +*/ +NTSTATUS tls_socket_recv(struct tls_context *tls, void *buf, size_t wantlen, + size_t *nread) +{ + int ret; + NTSTATUS status; + if (tls->tls_enabled && tls->tls_detect) { + status = socket_recv(tls->socket, &tls->first_byte, 1, nread, 0); + 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, 0); + } + + status = tls_handshake(tls); + NT_STATUS_NOT_OK_RETURN(status); + + ret = gnutls_record_recv(tls->session, buf, wantlen); + if (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN) { + return STATUS_MORE_ENTRIES; + } + if (ret < 0) { + DEBUG(0,("gnutls_record_recv failed - %s\n", gnutls_strerror(ret))); + return NT_STATUS_UNEXPECTED_NETWORK_ERROR; + } + *nread = ret; + return NT_STATUS_OK; +} + + +/* + send data either by tls or normal socket_recv +*/ +NTSTATUS tls_socket_send(struct tls_context *tls, const DATA_BLOB *blob, size_t *sendlen) +{ + NTSTATUS status; + int ret; + + if (!tls->tls_enabled) { + return socket_send(tls->socket, blob, sendlen, 0); + } + + status = tls_handshake(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) { + return STATUS_MORE_ENTRIES; + } + if (ret < 0) { + DEBUG(0,("gnutls_record_send failed - %s\n", 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 tls_params *params; + int ret; + const char *keyfile = lp_tls_keyfile(); + const char *certfile = lp_tls_certfile(); + const char *cafile = lp_tls_cafile(); + const char *crlfile = lp_tls_crlfile(); + void tls_cert_generate(TALLOC_CTX *, const char *, const char *, const char *); + + params = talloc(mem_ctx, struct tls_params); + if (params == NULL) return NULL; + + if (!lp_tls_enabled() || keyfile == NULL || *keyfile == 0) { + params->tls_enabled = False; + 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; + + 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; + return params; + +init_failed: + DEBUG(0,("GNUTLS failed to initialise - %s\n", gnutls_strerror(ret))); + params->tls_enabled = False; + return params; +} + + +/* + setup for a new connection +*/ +struct tls_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; + + tls = talloc(socket, struct tls_context); + if (tls == NULL) return NULL; + + tls->socket = socket; + tls->fde = fde; + + if (!params->tls_enabled) { + tls->tls_enabled = False; + return tls; + } + +#define TLSCHECK(call) do { \ + ret = call; \ + if (ret < 0) { \ + DEBUG(0,("TLS %s - %s\n", #call, gnutls_strerror(ret))); \ + goto failed; \ + } \ +} while (0) + + 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->params = params; + tls->done_handshake = False; + tls->have_first_byte = False; + tls->tls_enabled = True; + + return tls; + +failed: + DEBUG(0,("TLS init connection failed - %s\n", gnutls_strerror(ret))); + tls->tls_enabled = False; + params->tls_enabled = False; + return tls; +} + +BOOL tls_enabled(struct tls_context *tls) +{ + return tls->tls_enabled; +} + +BOOL tls_support(struct tls_params *params) +{ + return params->tls_enabled; +} + + +#else + +/* for systems without tls we just map the tls socket calls to the + normal socket calls */ + +struct tls_params *tls_initialise(TALLOC_CTX *mem_ctx) +{ + return talloc_new(mem_ctx); +} + +struct tls_context *tls_init_server(struct tls_params *params, + struct socket_context *sock, + struct fd_event *fde, + const char *plain_chars) +{ + if (plain_chars == NULL) return NULL; + return (struct tls_context *)sock; +} + + +NTSTATUS tls_socket_recv(struct tls_context *tls, void *buf, size_t wantlen, + size_t *nread) +{ + return socket_recv((struct socket_context *)tls, buf, wantlen, nread, 0); +} + +NTSTATUS tls_socket_send(struct tls_context *tls, const DATA_BLOB *blob, size_t *sendlen) +{ + return socket_send((struct socket_context *)tls, blob, sendlen, 0); +} + +BOOL tls_enabled(struct tls_context *tls) +{ + return False; +} + +BOOL tls_support(struct tls_params *params) +{ + return False; +} + +#endif |