/* Unix SMB/CIFS implementation. Connect GENSEC to an external SASL lib Copyright (C) Andrew Bartlett <abartlet@samba.org> 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 "auth/auth.h" #include "auth/credentials/credentials.h" #include "auth/gensec/gensec.h" #include "auth/gensec/gensec_proto.h" #include "lib/socket/socket.h" #include <sasl/sasl.h> struct gensec_sasl_state { sasl_conn_t *conn; int step; }; static NTSTATUS sasl_nt_status(int sasl_ret) { switch (sasl_ret) { case SASL_CONTINUE: return NT_STATUS_MORE_PROCESSING_REQUIRED; case SASL_NOMEM: return NT_STATUS_NO_MEMORY; case SASL_BADPARAM: case SASL_NOMECH: return NT_STATUS_INVALID_PARAMETER; case SASL_BADMAC: return NT_STATUS_ACCESS_DENIED; case SASL_OK: return NT_STATUS_OK; default: return NT_STATUS_UNSUCCESSFUL; } } static int gensec_sasl_get_user(void *context, int id, const char **result, unsigned *len) { struct gensec_security *gensec_security = talloc_get_type(context, struct gensec_security); const char *username = cli_credentials_get_username(gensec_get_credentials(gensec_security)); if (id != SASL_CB_USER && id != SASL_CB_AUTHNAME) { return SASL_FAIL; } *result = username; return SASL_OK; } static int gensec_sasl_get_realm(void *context, int id, const char **availrealms, const char **result) { struct gensec_security *gensec_security = talloc_get_type(context, struct gensec_security); const char *realm = cli_credentials_get_realm(gensec_get_credentials(gensec_security)); int i; if (id != SASL_CB_GETREALM) { return SASL_FAIL; } for (i=0; availrealms && availrealms[i]; i++) { if (strcasecmp_m(realm, availrealms[i]) == 0) { result[i] = availrealms[i]; return SASL_OK; } } /* None of the realms match, so lets not specify one */ *result = ""; return SASL_OK; } static int gensec_sasl_get_password(sasl_conn_t *conn, void *context, int id, sasl_secret_t **psecret) { struct gensec_security *gensec_security = talloc_get_type(context, struct gensec_security); const char *password = cli_credentials_get_password(gensec_get_credentials(gensec_security)); sasl_secret_t *secret; if (!password) { *psecret = NULL; return SASL_OK; } secret = talloc_size(gensec_security, sizeof(sasl_secret_t)+strlen(password)); if (!secret) { return SASL_NOMEM; } secret->len = strlen(password); safe_strcpy((char*)secret->data, password, secret->len+1); *psecret = secret; return SASL_OK; } static int gensec_sasl_dispose(struct gensec_sasl_state *gensec_sasl_state) { sasl_dispose(&gensec_sasl_state->conn); return SASL_OK; } static NTSTATUS gensec_sasl_client_start(struct gensec_security *gensec_security) { struct gensec_sasl_state *gensec_sasl_state; const char *service = gensec_get_target_service(gensec_security); const char *target_name = gensec_get_target_hostname(gensec_security); struct socket_address *local_socket_addr = gensec_get_my_addr(gensec_security); struct socket_address *remote_socket_addr = gensec_get_peer_addr(gensec_security); char *local_addr = NULL; char *remote_addr = NULL; int sasl_ret; sasl_callback_t *callbacks; gensec_sasl_state = talloc(gensec_security, struct gensec_sasl_state); if (!gensec_sasl_state) { return NT_STATUS_NO_MEMORY; } callbacks = talloc_array(gensec_sasl_state, sasl_callback_t, 5); callbacks[0].id = SASL_CB_USER; callbacks[0].proc = gensec_sasl_get_user; callbacks[0].context = gensec_security; callbacks[1].id = SASL_CB_AUTHNAME; callbacks[1].proc = gensec_sasl_get_user; callbacks[1].context = gensec_security; callbacks[2].id = SASL_CB_GETREALM; callbacks[2].proc = gensec_sasl_get_realm; callbacks[2].context = gensec_security; callbacks[3].id = SASL_CB_PASS; callbacks[3].proc = gensec_sasl_get_password; callbacks[3].context = gensec_security; callbacks[4].id = SASL_CB_LIST_END; callbacks[4].proc = NULL; callbacks[4].context = NULL; gensec_security->private_data = gensec_sasl_state; if (local_socket_addr) { local_addr = talloc_asprintf(gensec_sasl_state, "%s;%d", local_socket_addr->addr, local_socket_addr->port); } if (remote_socket_addr) { remote_addr = talloc_asprintf(gensec_sasl_state, "%s;%d", remote_socket_addr->addr, remote_socket_addr->port); } gensec_sasl_state->step = 0; sasl_ret = sasl_client_new(service, target_name, local_addr, remote_addr, callbacks, 0, &gensec_sasl_state->conn); if (sasl_ret == SASL_OK || sasl_ret == SASL_CONTINUE) { sasl_security_properties_t props; talloc_set_destructor(gensec_sasl_state, gensec_sasl_dispose); ZERO_STRUCT(props); if (gensec_security->want_features & GENSEC_FEATURE_SIGN) { props.min_ssf = 1; } if (gensec_security->want_features & GENSEC_FEATURE_SEAL) { props.min_ssf = 40; } props.max_ssf = UINT_MAX; props.maxbufsize = 65536; sasl_ret = sasl_setprop(gensec_sasl_state->conn, SASL_SEC_PROPS, &props); if (sasl_ret != SASL_OK) { return sasl_nt_status(sasl_ret); } } else { DEBUG(1, ("GENSEC SASL: client_new failed: %s\n", sasl_errdetail(gensec_sasl_state->conn))); } return sasl_nt_status(sasl_ret); } static NTSTATUS gensec_sasl_update(struct gensec_security *gensec_security, TALLOC_CTX *out_mem_ctx, const DATA_BLOB in, DATA_BLOB *out) { struct gensec_sasl_state *gensec_sasl_state = talloc_get_type(gensec_security->private_data, struct gensec_sasl_state); int sasl_ret; const char *out_data; unsigned int out_len; if (gensec_sasl_state->step == 0) { const char *mech; sasl_ret = sasl_client_start(gensec_sasl_state->conn, gensec_security->ops->sasl_name, NULL, &out_data, &out_len, &mech); } else { sasl_ret = sasl_client_step(gensec_sasl_state->conn, (char*)in.data, in.length, NULL, &out_data, &out_len); } if (sasl_ret == SASL_OK || sasl_ret == SASL_CONTINUE) { *out = data_blob_talloc(out_mem_ctx, out_data, out_len); } else { DEBUG(1, ("GENSEC SASL: step %d update failed: %s\n", gensec_sasl_state->step, sasl_errdetail(gensec_sasl_state->conn))); } gensec_sasl_state->step++; return sasl_nt_status(sasl_ret); } static NTSTATUS gensec_sasl_unwrap_packets(struct gensec_security *gensec_security, TALLOC_CTX *out_mem_ctx, const DATA_BLOB *in, DATA_BLOB *out, size_t *len_processed) { struct gensec_sasl_state *gensec_sasl_state = talloc_get_type(gensec_security->private_data, struct gensec_sasl_state); const char *out_data; unsigned int out_len; int sasl_ret = sasl_decode(gensec_sasl_state->conn, (char*)in->data, in->length, &out_data, &out_len); if (sasl_ret == SASL_OK) { *out = data_blob_talloc(out_mem_ctx, out_data, out_len); *len_processed = in->length; } else { DEBUG(1, ("GENSEC SASL: unwrap failed: %s\n", sasl_errdetail(gensec_sasl_state->conn))); } return sasl_nt_status(sasl_ret); } static NTSTATUS gensec_sasl_wrap_packets(struct gensec_security *gensec_security, TALLOC_CTX *out_mem_ctx, const DATA_BLOB *in, DATA_BLOB *out, size_t *len_processed) { struct gensec_sasl_state *gensec_sasl_state = talloc_get_type(gensec_security->private_data, struct gensec_sasl_state); const char *out_data; unsigned int out_len; int sasl_ret = sasl_encode(gensec_sasl_state->conn, (char*)in->data, in->length, &out_data, &out_len); if (sasl_ret == SASL_OK) { *out = data_blob_talloc(out_mem_ctx, out_data, out_len); *len_processed = in->length; } else { DEBUG(1, ("GENSEC SASL: wrap failed: %s\n", sasl_errdetail(gensec_sasl_state->conn))); } return sasl_nt_status(sasl_ret); } /* Try to figure out what features we actually got on the connection */ static bool gensec_sasl_have_feature(struct gensec_security *gensec_security, uint32_t feature) { struct gensec_sasl_state *gensec_sasl_state = talloc_get_type(gensec_security->private_data, struct gensec_sasl_state); sasl_ssf_t ssf; int sasl_ret = sasl_getprop(gensec_sasl_state->conn, SASL_SSF, (const void**)&ssf); if (sasl_ret != SASL_OK) { return false; } if (feature & GENSEC_FEATURE_SIGN) { if (ssf == 0) { return false; } if (ssf >= 1) { return true; } } if (feature & GENSEC_FEATURE_SEAL) { if (ssf <= 1) { return false; } if (ssf > 1) { return true; } } return false; } /* This could in theory work with any SASL mech */ static const struct gensec_security_ops gensec_sasl_security_ops = { .name = "sasl-DIGEST-MD5", .sasl_name = "DIGEST-MD5", .client_start = gensec_sasl_client_start, .update = gensec_sasl_update, .wrap_packets = gensec_sasl_wrap_packets, .unwrap_packets = gensec_sasl_unwrap_packets, .have_feature = gensec_sasl_have_feature, .enabled = true, .priority = GENSEC_SASL }; static int gensec_sasl_log(void *context, int sasl_log_level, const char *message) { int dl; switch (sasl_log_level) { case SASL_LOG_NONE: dl = 0; break; case SASL_LOG_ERR: dl = 1; break; case SASL_LOG_FAIL: dl = 2; break; case SASL_LOG_WARN: dl = 3; break; case SASL_LOG_NOTE: dl = 5; break; case SASL_LOG_DEBUG: dl = 10; break; case SASL_LOG_TRACE: dl = 11; break; #if DEBUG_PASSWORD case SASL_LOG_PASS: dl = 100; break; #endif default: dl = 0; break; } DEBUG(dl, ("gensec_sasl: %s\n", message)); return SASL_OK; } NTSTATUS gensec_sasl_init(void) { NTSTATUS ret; int sasl_ret; #if 0 int i; const char **sasl_mechs; #endif static const sasl_callback_t callbacks[] = { { .id = SASL_CB_LOG, .proc = gensec_sasl_log, .context = NULL, }, { .id = SASL_CB_LIST_END, .proc = gensec_sasl_log, .context = NULL, } }; sasl_ret = sasl_client_init(callbacks); if (sasl_ret == SASL_NOMECH) { /* Nothing to do here */ return NT_STATUS_OK; } if (sasl_ret != SASL_OK) { return sasl_nt_status(sasl_ret); } /* For now, we just register DIGEST-MD5 */ #if 1 ret = gensec_register(&gensec_sasl_security_ops); if (!NT_STATUS_IS_OK(ret)) { DEBUG(0,("Failed to register '%s' gensec backend!\n", gensec_sasl_security_ops.name)); return ret; } #else sasl_mechs = sasl_global_listmech(); for (i = 0; sasl_mechs && sasl_mechs[i]; i++) { const struct gensec_security_ops *oldmech; struct gensec_security_ops *newmech; oldmech = gensec_security_by_sasl_name(NULL, sasl_mechs[i]); if (oldmech) { continue; } newmech = talloc(talloc_autofree_context(), struct gensec_security_ops); if (!newmech) { return NT_STATUS_NO_MEMORY; } *newmech = gensec_sasl_security_ops; newmech->sasl_name = talloc_strdup(newmech, sasl_mechs[i]); newmech->name = talloc_asprintf(newmech, "sasl-%s", sasl_mechs[i]); if (!newmech->sasl_name || !newmech->name) { return NT_STATUS_NO_MEMORY; } ret = gensec_register(newmech); if (!NT_STATUS_IS_OK(ret)) { DEBUG(0,("Failed to register '%s' gensec backend!\n", gensec_sasl_security_ops.name)); return ret; } } #endif return NT_STATUS_OK; }