kms client/server: replace unix domain socket file with socketpair after connecting (fixes issue of .gsr-kms-socket files remaining in $HOME)

This commit is contained in:
dec05eba
2023-11-12 10:55:02 +01:00
parent 1ac862d155
commit 290db495ff
5 changed files with 175 additions and 48 deletions

View File

@@ -12,6 +12,12 @@
#include <sys/wait.h>
#include <sys/capability.h>
#define GSR_SOCKET_PAIR_LOCAL 0
#define GSR_SOCKET_PAIR_REMOTE 1
static void cleanup_initial_socket(gsr_kms_client *self, bool kill_server);
static int gsr_kms_client_replace_connection(gsr_kms_client *self);
static bool generate_random_characters(char *buffer, int buffer_size, const char *alphabet, size_t alphabet_size) {
int fd = open("/dev/urandom", O_RDONLY);
if(fd == -1) {
@@ -34,6 +40,14 @@ static bool generate_random_characters(char *buffer, int buffer_size, const char
return true;
}
static void close_fds(gsr_kms_response *response) {
for(int i = 0; i < response->num_fds; ++i) {
if(response->fds[i].fd > 0)
close(response->fds[i].fd);
response->fds[i].fd = 0;
}
}
static int send_msg_to_server(int server_fd, gsr_kms_request *request) {
struct iovec iov;
iov.iov_base = request;
@@ -72,9 +86,7 @@ static int recv_msg_from_server(int server_fd, gsr_kms_response *response) {
response->fds[i].fd = fds[i];
}
} else {
for(int i = 0; i < response->num_fds; ++i) {
response->fds[i].fd = 0;
}
close_fds(response);
}
}
@@ -142,13 +154,15 @@ static bool find_program_in_path(const char *program_name, char *filepath, int f
int gsr_kms_client_init(gsr_kms_client *self, const char *card_path) {
int result = -1;
self->kms_server_pid = -1;
self->socket_fd = -1;
self->client_fd = -1;
self->socket_path[0] = '\0';
self->initial_socket_fd = -1;
self->initial_client_fd = -1;
self->initial_socket_path[0] = '\0';
self->socket_pair[0] = -1;
self->socket_pair[1] = -1;
struct sockaddr_un local_addr = {0};
struct sockaddr_un remote_addr = {0};
if(!create_socket_path(self->socket_path, sizeof(self->socket_path))) {
if(!create_socket_path(self->initial_socket_path, sizeof(self->initial_socket_path))) {
fprintf(stderr, "gsr error: gsr_kms_client_init: failed to create path to kms socket\n");
return -1;
}
@@ -185,20 +199,25 @@ int gsr_kms_client_init(gsr_kms_client *self, const char *card_path) {
}
}
self->socket_fd = socket(AF_UNIX, SOCK_STREAM, 0);
if(self->socket_fd == -1) {
if(socketpair(AF_UNIX, SOCK_STREAM, 0, self->socket_pair) == -1) {
fprintf(stderr, "gsr error: gsr_kms_client_init: socketpair failed, error: %s\n", strerror(errno));
goto err;
}
self->initial_socket_fd = socket(AF_UNIX, SOCK_STREAM, 0);
if(self->initial_socket_fd == -1) {
fprintf(stderr, "gsr error: gsr_kms_client_init: socket failed, error: %s\n", strerror(errno));
goto err;
}
local_addr.sun_family = AF_UNIX;
strncpy_safe(local_addr.sun_path, self->socket_path, sizeof(local_addr.sun_path));
if(bind(self->socket_fd, (struct sockaddr*)&local_addr, sizeof(local_addr.sun_family) + strlen(local_addr.sun_path)) == -1) {
strncpy_safe(local_addr.sun_path, self->initial_socket_path, sizeof(local_addr.sun_path));
if(bind(self->initial_socket_fd, (struct sockaddr*)&local_addr, sizeof(local_addr.sun_family) + strlen(local_addr.sun_path)) == -1) {
fprintf(stderr, "gsr error: gsr_kms_client_init: failed to bind socket, error: %s\n", strerror(errno));
goto err;
}
if(listen(self->socket_fd, 1) == -1) {
if(listen(self->initial_socket_fd, 1) == -1) {
fprintf(stderr, "gsr error: gsr_kms_client_init: failed to listen on socket, error: %s\n", strerror(errno));
goto err;
}
@@ -209,13 +228,13 @@ int gsr_kms_client_init(gsr_kms_client *self, const char *card_path) {
goto err;
} else if(pid == 0) { /* child */
if(inside_flatpak) {
const char *args[] = { "flatpak-spawn", "--host", "pkexec", "flatpak", "run", "--command=gsr-kms-server", "com.dec05eba.gpu_screen_recorder", self->socket_path, card_path, NULL };
const char *args[] = { "flatpak-spawn", "--host", "pkexec", "flatpak", "run", "--command=gsr-kms-server", "com.dec05eba.gpu_screen_recorder", self->initial_socket_path, card_path, NULL };
execvp(args[0], (char *const*)args);
} else if(has_perm) {
const char *args[] = { server_filepath, self->socket_path, card_path, NULL };
const char *args[] = { server_filepath, self->initial_socket_path, card_path, NULL };
execvp(args[0], (char *const*)args);
} else {
const char *args[] = { "pkexec", server_filepath, self->socket_path, card_path, NULL };
const char *args[] = { "pkexec", server_filepath, self->initial_socket_path, card_path, NULL };
execvp(args[0], (char *const*)args);
}
fprintf(stderr, "gsr error: gsr_kms_client_init: execvp failed, error: %s\n", strerror(errno));
@@ -229,16 +248,16 @@ int gsr_kms_client_init(gsr_kms_client *self, const char *card_path) {
struct timeval tv;
fd_set rfds;
FD_ZERO(&rfds);
FD_SET(self->socket_fd, &rfds);
FD_SET(self->initial_socket_fd, &rfds);
tv.tv_sec = 0;
tv.tv_usec = 100 * 1000; // 100 ms
int select_res = select(1 + self->socket_fd, &rfds, NULL, NULL, &tv);
int select_res = select(1 + self->initial_socket_fd, &rfds, NULL, NULL, &tv);
if(select_res > 0) {
socklen_t sock_len = 0;
self->client_fd = accept(self->socket_fd, (struct sockaddr*)&remote_addr, &sock_len);
if(self->client_fd == -1) {
self->initial_client_fd = accept(self->initial_socket_fd, (struct sockaddr*)&remote_addr, &sock_len);
if(self->initial_client_fd == -1) {
fprintf(stderr, "gsr error: gsr_kms_client_init: accept failed on socket, error: %s\n", strerror(errno));
goto err;
}
@@ -260,6 +279,13 @@ int gsr_kms_client_init(gsr_kms_client *self, const char *card_path) {
}
fprintf(stderr, "gsr info: gsr_kms_client_init: server connected\n");
fprintf(stderr, "gsr info: replacing file-backed unix domain socket with socketpair\n");
if(gsr_kms_client_replace_connection(self) != 0)
goto err;
cleanup_initial_socket(self, false);
fprintf(stderr, "gsr info: using socketpair\n");
return 0;
err:
@@ -267,47 +293,104 @@ int gsr_kms_client_init(gsr_kms_client *self, const char *card_path) {
return result;
}
void gsr_kms_client_deinit(gsr_kms_client *self) {
if(self->client_fd != -1) {
close(self->client_fd);
self->client_fd = -1;
void cleanup_initial_socket(gsr_kms_client *self, bool kill_server) {
if(self->initial_client_fd != -1) {
close(self->initial_client_fd);
self->initial_client_fd = -1;
}
if(self->socket_fd != -1) {
close(self->socket_fd);
self->socket_fd = -1;
if(self->initial_socket_fd != -1) {
close(self->initial_socket_fd);
self->initial_socket_fd = -1;
}
if(self->kms_server_pid != -1) {
if(kill_server && self->kms_server_pid != -1) {
kill(self->kms_server_pid, SIGINT);
int status;
waitpid(self->kms_server_pid, &status, 0);
self->kms_server_pid = -1;
}
if(self->socket_path[0] != '\0') {
remove(self->socket_path);
self->socket_path[0] = '\0';
if(self->initial_socket_path[0] != '\0') {
remove(self->initial_socket_path);
self->initial_socket_path[0] = '\0';
}
}
int gsr_kms_client_get_kms(gsr_kms_client *self, gsr_kms_response *response) {
response->result = KMS_RESULT_FAILED_TO_SEND;
strcpy(response->err_msg, "failed to send");
void gsr_kms_client_deinit(gsr_kms_client *self) {
cleanup_initial_socket(self, true);
for(int i = 0; i < 2; ++i) {
if(self->socket_pair[i] > 0) {
close(self->socket_pair[i]);
self->socket_pair[i] = -1;
}
}
}
int gsr_kms_client_replace_connection(gsr_kms_client *self) {
gsr_kms_response response;
response.version = 0;
response.result = KMS_RESULT_FAILED_TO_SEND;
response.err_msg[0] = '\0';
gsr_kms_request request;
request.type = KMS_REQUEST_TYPE_GET_KMS;
if(send_msg_to_server(self->client_fd, &request) == -1) {
fprintf(stderr, "gsr error: gsr_kms_client_get_kms: failed to send request message to server\n");
request.version = GSR_KMS_PROTOCOL_VERSION;
request.type = KMS_REQUEST_TYPE_REPLACE_CONNECTION;
request.new_connection_fd = self->socket_pair[GSR_SOCKET_PAIR_REMOTE];
if(send_msg_to_server(self->initial_client_fd, &request) == -1) {
fprintf(stderr, "gsr error: gsr_kms_client_replace_connection: failed to send request message to server\n");
return -1;
}
const int recv_res = recv_msg_from_server(self->client_fd, response);
const int recv_res = recv_msg_from_server(self->socket_pair[GSR_SOCKET_PAIR_LOCAL], &response);
if(recv_res == 0) {
fprintf(stderr, "gsr warning: gsr_kms_client_get_kms: kms server shut down\n");
fprintf(stderr, "gsr warning: gsr_kms_client_replace_connection: kms server shut down\n");
return -1;
} else if(recv_res == -1) {
fprintf(stderr, "gsr error: gsr_kms_client_get_kms: failed to receive response\n");
fprintf(stderr, "gsr error: gsr_kms_client_replace_connection: failed to receive response\n");
return -1;
}
if(response.version != GSR_KMS_PROTOCOL_VERSION) {
fprintf(stderr, "gsr error: gsr_kms_client_replace_connection: expected gsr-kms-server protocol version to be %u, but it's %u\n", GSR_KMS_PROTOCOL_VERSION, response.version);
/*close_fds(response);*/
return -1;
}
return 0;
}
int gsr_kms_client_get_kms(gsr_kms_client *self, gsr_kms_response *response) {
response->version = 0;
response->result = KMS_RESULT_FAILED_TO_SEND;
response->err_msg[0] = '\0';
gsr_kms_request request;
request.version = GSR_KMS_PROTOCOL_VERSION;
request.type = KMS_REQUEST_TYPE_GET_KMS;
request.new_connection_fd = 0;
if(send_msg_to_server(self->socket_pair[GSR_SOCKET_PAIR_LOCAL], &request) == -1) {
fprintf(stderr, "gsr error: gsr_kms_client_get_kms: failed to send request message to server\n");
strcpy(response->err_msg, "failed to send");
return -1;
}
const int recv_res = recv_msg_from_server(self->socket_pair[GSR_SOCKET_PAIR_LOCAL], response);
if(recv_res == 0) {
fprintf(stderr, "gsr warning: gsr_kms_client_get_kms: kms server shut down\n");
strcpy(response->err_msg, "failed to receive");
return -1;
} else if(recv_res == -1) {
fprintf(stderr, "gsr error: gsr_kms_client_get_kms: failed to receive response\n");
strcpy(response->err_msg, "failed to receive");
return -1;
}
if(response->version != GSR_KMS_PROTOCOL_VERSION) {
fprintf(stderr, "gsr error: gsr_kms_client_get_kms: expected gsr-kms-server protocol version to be %u, but it's %u\n", GSR_KMS_PROTOCOL_VERSION, response->version);
/*close_fds(response);*/
strcpy(response->err_msg, "mismatching protocol version");
return -1;
}

View File

@@ -7,9 +7,10 @@
typedef struct {
pid_t kms_server_pid;
int socket_fd;
int client_fd;
char socket_path[PATH_MAX];
int initial_socket_fd;
int initial_client_fd;
char initial_socket_path[PATH_MAX];
int socket_pair[2];
} gsr_kms_client;
/* |card_path| should be a path to card, for example /dev/dri/card0 */