#include <lttng/lttng-consumer.h>
#include <lttngerr.h>
+#include <runas.h>
#include "channel.h"
#include "compat/poll.h"
const char *opt_tracing_group;
static int opt_sig_parent;
static int opt_daemon;
+static int opt_no_kernel;
static int is_root; /* Set to 1 if the daemon is running as root */
static pid_t ppid; /* Parent PID for --sig-parent option */
static char *rundir;
pthread_mutex_destroy(&kconsumer_data.pid_mutex);
- DBG("Closing kernel fd");
- close(kernel_tracer_fd);
-
- if (is_root) {
+ if (is_root && !opt_no_kernel) {
+ DBG2("Closing kernel fd");
+ close(kernel_tracer_fd);
DBG("Unloading kernel modules");
modprobe_remove_kernel_modules();
}
close(thread_quit_pipe[1]);
/* <fun> */
- MSG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
+ DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
"Matthew, BEET driven development works!%c[%dm",
27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
/* </fun> */
* Send all stream fds of kernel channel to the consumer.
*/
static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
- int sock, struct ltt_kernel_channel *channel)
+ int sock, struct ltt_kernel_channel *channel,
+ uid_t uid, gid_t gid)
{
int ret;
struct ltt_kernel_stream *stream;
lkm.u.stream.state = stream->state;
lkm.u.stream.output = channel->channel->attr.output;
lkm.u.stream.mmap_len = 0; /* for kernel */
+ lkm.u.stream.uid = uid;
+ lkm.u.stream.gid = gid;
strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
lkm.u.stream.mmap_len = 0; /* for kernel */
+ lkm.u.stream.uid = session->uid;
+ lkm.u.stream.gid = session->gid;
strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
}
cds_list_for_each_entry(chan, &session->channel_list.head, list) {
- ret = send_kconsumer_channel_streams(consumer_data, sock, chan);
+ ret = send_kconsumer_channel_streams(consumer_data, sock, chan,
+ session->uid, session->gid);
if (ret < 0) {
goto error;
}
*/
if (session->kernel_session->consumer_fds_sent == 1) {
ret = send_kconsumer_channel_streams(consumer_data,
- session->kernel_session->consumer_fd, channel);
+ session->kernel_session->consumer_fd, channel,
+ session->uid, session->gid);
if (ret < 0) {
goto error;
}
int ret;
char *type = "debugfs";
- ret = mkdir_recursive(path, S_IRWXU | S_IRWXG, geteuid(), getegid());
+ ret = mkdir_recursive_run_as(path, S_IRWXU | S_IRWXG, geteuid(), getegid());
if (ret < 0) {
PERROR("Cannot create debugfs path");
goto error;
static int create_ust_session(struct ltt_session *session,
struct lttng_domain *domain)
{
- int ret;
- unsigned int uid;
struct ltt_ust_session *lus = NULL;
+ int ret;
switch (domain->type) {
case LTTNG_DOMAIN_UST:
DBG("Creating UST session");
- uid = session->uid;
- lus = trace_ust_create_session(session->path, uid, domain);
+ lus = trace_ust_create_session(session->path, session->id, domain);
if (lus == NULL) {
ret = LTTCOMM_UST_SESS_FAIL;
goto error;
}
- ret = mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
- geteuid(), allowed_group());
+ ret = mkdir_recursive_run_as(lus->pathname, S_IRWXU | S_IRWXG,
+ session->uid, session->gid);
if (ret < 0) {
if (ret != -EEXIST) {
ERR("Trace directory creation error");
ERR("Unknown UST domain on create session %d", domain->type);
goto error;
}
+ lus->uid = session->uid;
+ lus->gid = session->gid;
session->ust_session = lus;
return LTTCOMM_OK;
session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
}
- ret = mkdir_recursive(session->kernel_session->trace_path,
- S_IRWXU | S_IRWXG, geteuid(), allowed_group());
+ ret = mkdir_recursive_run_as(session->kernel_session->trace_path,
+ S_IRWXU | S_IRWXG, session->uid, session->gid);
if (ret < 0) {
if (ret != -EEXIST) {
ERR("Trace directory creation error");
goto error;
}
}
+ session->kernel_session->uid = session->uid;
+ session->kernel_session->gid = session->gid;
error:
return ret;
}
+/*
+ * Check if the UID or GID match the session. Root user has access to
+ * all sessions.
+ */
+static int session_access_ok(struct ltt_session *session,
+ uid_t uid, gid_t gid)
+{
+ if (uid != session->uid && gid != session->gid
+ && uid != 0) {
+ return 0;
+ } else {
+ return 1;
+ }
+}
+
+static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
+{
+ unsigned int i = 0;
+ struct ltt_session *session;
+
+ DBG("Counting number of available session for UID %d GID %d",
+ uid, gid);
+ cds_list_for_each_entry(session, &session_list_ptr->head, list) {
+ /*
+ * Only list the sessions the user can control.
+ */
+ if (!session_access_ok(session, uid, gid)) {
+ continue;
+ }
+ i++;
+ }
+ return i;
+}
+
/*
* Using the session list, filled a lttng_session array to send back to the
* client for session listing.
* The session list lock MUST be acquired before calling this function. Use
* session_lock_list() and session_unlock_list().
*/
-static void list_lttng_sessions(struct lttng_session *sessions)
+static void list_lttng_sessions(struct lttng_session *sessions,
+ uid_t uid, gid_t gid)
{
- int i = 0;
+ unsigned int i = 0;
struct ltt_session *session;
- DBG("Getting all available session");
+ DBG("Getting all available session for UID %d GID %d",
+ uid, gid);
/*
* Iterate over session list and append data after the control struct in
* the buffer.
*/
cds_list_for_each_entry(session, &session_list_ptr->head, list) {
+ /*
+ * Only list the sessions the user can control.
+ */
+ if (!session_access_ok(session, uid, gid)) {
+ continue;
+ }
strncpy(sessions[i].path, session->path, PATH_MAX);
sessions[i].path[PATH_MAX - 1] = '\0';
strncpy(sessions[i].name, session->name, NAME_MAX);
/*
* Command LTTNG_CREATE_SESSION processed by the client thread.
*/
-static int cmd_create_session(char *name, char *path)
+static int cmd_create_session(char *name, char *path, struct ucred *creds)
{
int ret;
- ret = session_create(name, path);
+ ret = session_create(name, path, creds->uid, creds->gid);
if (ret != LTTCOMM_OK) {
goto error;
}
switch (domain) {
case LTTNG_DOMAIN_KERNEL:
/* Can't register a consumer if there is already one */
- if (session->kernel_session->consumer_fd != 0) {
+ if (session->kernel_session->consumer_fds_sent != 0) {
ret = LTTCOMM_KERN_CONSUMER_FAIL;
goto error;
}
DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
+ if (opt_no_kernel && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
+ ret = LTTCOMM_KERN_NA;
+ goto error;
+ }
+
/*
* Check for command that don't needs to allocate a returned payload. We do
* this here so we don't have to make the call for no payload at each
break;
}
+ /*
+ * Check that the UID or GID match that of the tracing session.
+ * The root user can interact with all sessions.
+ */
+ if (need_tracing_session) {
+ if (!session_access_ok(cmd_ctx->session,
+ cmd_ctx->creds.uid, cmd_ctx->creds.gid)) {
+ ret = LTTCOMM_EPERM;
+ goto error;
+ }
+ }
+
/* Process by command type */
switch (cmd_ctx->lsm->cmd_type) {
case LTTNG_ADD_CONTEXT:
case LTTNG_CREATE_SESSION:
{
ret = cmd_create_session(cmd_ctx->lsm->session.name,
- cmd_ctx->lsm->session.path);
+ cmd_ctx->lsm->session.path, &cmd_ctx->creds);
break;
}
case LTTNG_DESTROY_SESSION:
}
case LTTNG_LIST_SESSIONS:
{
- session_lock_list();
+ unsigned int nr_sessions;
- if (session_list_ptr->count == 0) {
+ session_lock_list();
+ nr_sessions = lttng_sessions_count(cmd_ctx->creds.uid, cmd_ctx->creds.gid);
+ if (nr_sessions == 0) {
ret = LTTCOMM_NO_SESSION;
session_unlock_list();
goto error;
}
-
- ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) *
- session_list_ptr->count);
+ ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * nr_sessions);
if (ret < 0) {
session_unlock_list();
goto setup_error;
}
/* Filled the session array */
- list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload));
+ list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload),
+ cmd_ctx->creds.uid, cmd_ctx->creds.gid);
session_unlock_list();
goto error;
}
+ /* Set socket option for credentials retrieval */
+ ret = lttcomm_setsockopt_creds_unix_sock(sock);
+ if (ret < 0) {
+ goto error;
+ }
+
/* Allocate context command to process the client request */
cmd_ctx = zmalloc(sizeof(struct command_ctx));
if (cmd_ctx == NULL) {
* the client.
*/
DBG("Receiving data from client ...");
- ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm,
- sizeof(struct lttcomm_session_msg));
+ ret = lttcomm_recv_creds_unix_sock(sock, cmd_ctx->lsm,
+ sizeof(struct lttcomm_session_msg), &cmd_ctx->creds);
if (ret <= 0) {
DBG("Nothing recv() from client... continuing");
close(sock);
ERR("Failed to send data back to client");
}
- clean_command_ctx(&cmd_ctx);
-
/* End of transmission */
close(sock);
+
+ clean_command_ctx(&cmd_ctx);
}
error:
fprintf(stderr, " -q, --quiet No output at all.\n");
fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
+ fprintf(stderr, " --no-kernel Disable kernel tracer\n");
}
/*
{ "quiet", 0, 0, 'q' },
{ "verbose", 0, 0, 'v' },
{ "verbose-consumer", 0, 0, 'Z' },
+ { "no-kernel", 0, 0, 'N' },
{ NULL, 0, 0, 0 }
};
while (1) {
int option_index = 0;
- c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:C:E:D:F:Z:u:t",
+ c = getopt_long(argc, argv, "dhqvVSN" "a:c:g:s:C:E:D:F:Z:u:t",
long_options, &option_index);
if (c == -1) {
break;
case 'G':
snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
break;
+ case 'N':
+ opt_no_kernel = 1;
+ break;
case 'q':
opt_quiet = 1;
break;
* Race window between mkdir and chown is OK because we are going from more
* permissive (root.root) to les permissive (root.tracing).
*/
-static int set_permissions(void)
+static int set_permissions(char *rundir)
{
int ret;
gid_t gid;
gid = allowed_group();
if (gid < 0) {
- if (is_root) {
- WARN("No tracing group detected");
- ret = 0;
- } else {
- ERR("Missing tracing group. Aborting execution.");
- ret = -1;
- }
+ WARN("No tracing group detected");
+ ret = 0;
goto end;
}
/* Set lttng run dir */
- ret = chown(LTTNG_RUNDIR, 0, gid);
+ ret = chown(rundir, 0, gid);
if (ret < 0) {
- ERR("Unable to set group on " LTTNG_RUNDIR);
+ ERR("Unable to set group on %s", rundir);
perror("chown");
}
}
/* Setup kernel tracer */
- init_kernel_tracer();
+ if (!opt_no_kernel) {
+ init_kernel_tracer();
+ }
/* Set ulimit for open files */
set_ulimit();
}
/* Set credentials to socket */
- if (is_root && ((ret = set_permissions()) < 0)) {
+ if (is_root && ((ret = set_permissions(rundir)) < 0)) {
goto exit;
}