1 files changed, 140 insertions, 84 deletions

diff --git a/kms/client/kms_client.c b/kms/client/kms_client.c
index 28922ff..018b25e 100644
--- a/kms/client/kms_client.c
+++ b/kms/client/kms_client.c
@@ -1,4 +1,5 @@
 #include "kms_client.h"
+#include "../../include/utils.h"
 #include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
@@ -10,6 +11,8 @@
 #include <sys/socket.h>
 #include <sys/un.h>
 #include <sys/wait.h>
+#include <poll.h>
+#include <sys/stat.h>
 #include <sys/capability.h>
 
 #define GSR_SOCKET_PAIR_LOCAL  0
@@ -18,34 +21,18 @@
 static void cleanup_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) {
-        perror("/dev/urandom");
-        return false;
-    }
-
-    if(read(fd, buffer, buffer_size) < buffer_size) {
-        fprintf(stderr, "Failed to read %d bytes from /dev/urandom\n", buffer_size);
-        close(fd);
-        return false;
-    }
-
-    for(int i = 0; i < buffer_size; ++i) {
-        unsigned char c = *(unsigned char*)&buffer[i];
-        buffer[i] = alphabet[c % alphabet_size];
-    }
-
-    close(fd);
-    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;
+    for(int i = 0; i < response->num_items; ++i) {
+        for(int j = 0; j < response->items[i].num_dma_bufs; ++j) {
+            gsr_kms_response_dma_buf *dma_buf = &response->items[i].dma_buf[j];
+            if(dma_buf->fd > 0) {
+                close(dma_buf->fd);
+                dma_buf->fd = -1;
+            }
+        }
+        response->items[i].num_dma_bufs = 0;
     }
+    response->num_items = 0;
 }
 
 static int send_msg_to_server(int server_fd, gsr_kms_request *request) {
@@ -78,7 +65,7 @@ static int send_msg_to_server(int server_fd, gsr_kms_request *request) {
     return sendmsg(server_fd, &response_message, 0);
 }
 
-static int recv_msg_from_server(int server_fd, gsr_kms_response *response) {
+static int recv_msg_from_server(int server_pid, int server_fd, gsr_kms_response *response) {
     struct iovec iov;
     iov.iov_base = response;
     iov.iov_len = sizeof(*response);
@@ -87,21 +74,40 @@ static int recv_msg_from_server(int server_fd, gsr_kms_response *response) {
     response_message.msg_iov = &iov;
     response_message.msg_iovlen = 1;
 
-    char cmsgbuf[CMSG_SPACE(sizeof(int) * GSR_KMS_MAX_PLANES)];
+    char cmsgbuf[CMSG_SPACE(sizeof(int) * GSR_KMS_MAX_ITEMS * GSR_KMS_MAX_DMA_BUFS)];
     memset(cmsgbuf, 0, sizeof(cmsgbuf));
     response_message.msg_control = cmsgbuf;
     response_message.msg_controllen = sizeof(cmsgbuf);
 
-    int res = recvmsg(server_fd, &response_message, MSG_WAITALL);
-    if(res <= 0)
-        return res;
+    int res = 0;
+    for(;;) {
+        res = recvmsg(server_fd, &response_message, MSG_DONTWAIT);
+        if(res <= 0 && (errno == EAGAIN || errno == EWOULDBLOCK)) {
+            // If we are replacing the connection and closing the application at the same time
+            // then recvmsg can get stuck (because the server died), so we prevent that by doing
+            // non-blocking recvmsg and checking if the server died
+            int status = 0;
+            int wait_result = waitpid(server_pid, &status, WNOHANG);
+            if(wait_result != 0) {
+                res = -1;
+                break;
+            }
+            usleep(1000);
+        } else {
+            break;
+        }
+    }
 
-    if(response->num_fds > 0) {
+    if(res > 0 && response->num_items > 0) {
         struct cmsghdr *cmsg = CMSG_FIRSTHDR(&response_message);
         if(cmsg) {
             int *fds = (int*)CMSG_DATA(cmsg);
-            for(int i = 0; i < response->num_fds; ++i) {
-                response->fds[i].fd = fds[i];
+            int fd_index = 0;
+            for(int i = 0; i < response->num_items; ++i) {
+                for(int j = 0; j < response->items[i].num_dma_bufs; ++j) {
+                    gsr_kms_response_dma_buf *dma_buf = &response->items[i].dma_buf[j];
+                    dma_buf->fd = fds[fd_index++];
+                }
             }
         } else {
             close_fds(response);
@@ -119,20 +125,48 @@ static bool create_socket_path(char *output_path, size_t output_path_size) {
 
     char random_characters[11];
     random_characters[10] = '\0';
-    if(!generate_random_characters(random_characters, 10, "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789", 62))
+    if(!generate_random_characters_standard_alphabet(random_characters, 10))
         return false;
 
     snprintf(output_path, output_path_size, "%s/.gsr-kms-socket-%s", home, random_characters);
     return true;
 }
 
-static void strncpy_safe(char *dst, const char *src, int len) {
-    int src_len = strlen(src);
-    int min_len = src_len;
-    if(len - 1 < min_len)
-        min_len = len - 1;
-    memcpy(dst, src, min_len);
-    dst[min_len] = '\0';
+static bool readlink_realpath(const char *filepath, char *buffer) {
+    char symlinked_path[PATH_MAX];
+    ssize_t bytes_written = readlink(filepath, symlinked_path, sizeof(symlinked_path) - 1);
+    if(bytes_written == -1 && errno == EINVAL) {
+        /* Not a symlink */
+        snprintf(symlinked_path, sizeof(symlinked_path), "%s", filepath);
+    } else if(bytes_written == -1) {
+        return false;
+    } else {
+        symlinked_path[bytes_written] = '\0';
+    }
+
+    if(!realpath(symlinked_path, buffer))
+        return false;
+
+    return true;
+}
+
+static bool strcat_safe(char *str, int size, const char *str_to_add) {
+    const int str_len = strlen(str);
+    const int str_to_add_len = strlen(str_to_add);
+    if(str_len + str_to_add_len + 1 >= size)
+        return false;
+
+    memcpy(str + str_len, str_to_add, str_to_add_len);
+    str[str_len + str_to_add_len] = '\0';
+    return true;
+}
+
+static void file_get_directory(char *filepath) {
+    char *end = strrchr(filepath, '/');
+    if(end == NULL)
+        filepath[0] = '\0';
+    else
+        *end = '\0';
 }
 
 static bool find_program_in_path(const char *program_name, char *filepath, int filepath_len) {
@@ -186,34 +220,52 @@ int gsr_kms_client_init(gsr_kms_client *self, const char *card_path) {
     }
 
     char server_filepath[PATH_MAX];
-    if(!find_program_in_path("gsr-kms-server", server_filepath, sizeof(server_filepath))) {
-        fprintf(stderr, "gsr error: gsr_kms_client_init: gsr-kms-server is not installed\n");
+    if(!readlink_realpath("/proc/self/exe", server_filepath)) {
+        fprintf(stderr, "gsr error: gsr_kms_client_init: failed to resolve /proc/self/exe\n");
         return -1;
     }
+    file_get_directory(server_filepath);
+
+    if(!strcat_safe(server_filepath, sizeof(server_filepath), "/gsr-kms-server")) {
+        fprintf(stderr, "gsr error: gsr_kms_client_init: gsr-kms-server path too long\n");
+        return -1;
+    }
+
+    if(access(server_filepath, F_OK) != 0) {
+        fprintf(stderr, "gsr info: gsr_kms_client_init: gsr-kms-server is not installed in the same directory as gpu-screen-recorder (%s not found), looking for gsr-kms-server in PATH instead\n", server_filepath);
+        if(!find_program_in_path("gsr-kms-server", server_filepath, sizeof(server_filepath)) || access(server_filepath, F_OK) != 0) {
+            fprintf(stderr, "gsr error: gsr_kms_client_init: gsr-kms-server was not found in PATH. Please install gpu-screen-recorder properly\n");
+            return -1;
+        }
+    }
+
+    fprintf(stderr, "gsr info: gsr_kms_client_init: setting up connection to %s\n", server_filepath);
 
-    bool has_perm = 0;
     const bool inside_flatpak = getenv("FLATPAK_ID") != NULL;
-    if(!inside_flatpak) {
-        if(geteuid() == 0) {
-            has_perm = true;
-        } else {
-            cap_t kms_server_cap = cap_get_file(server_filepath);
-            if(kms_server_cap) {
-                cap_flag_value_t res = 0;
-                cap_get_flag(kms_server_cap, CAP_SYS_ADMIN, CAP_PERMITTED, &res);
-                if(res == CAP_SET) {
-                    //fprintf(stderr, "has permission!\n");
-                    has_perm = true;
-                } else {
-                    //fprintf(stderr, "No permission:(\n");
-                }
-                cap_free(kms_server_cap);
+    const char *home = getenv("HOME");
+    if(!home)
+        home = "/tmp";
+
+    bool has_perm = 0;
+    if(geteuid() == 0) {
+        has_perm = true;
+    } else {
+        cap_t kms_server_cap = cap_get_file(server_filepath);
+        if(kms_server_cap) {
+            cap_flag_value_t res = CAP_CLEAR;
+            cap_get_flag(kms_server_cap, CAP_SYS_ADMIN, CAP_PERMITTED, &res);
+            if(res == CAP_SET) {
+                //fprintf(stderr, "has permission!\n");
+                has_perm = true;
             } else {
-                if(errno == ENODATA)
-                    fprintf(stderr, "gsr info: gsr_kms_client_init: gsr-kms-server is missing sys_admin cap and will require root authentication. To bypass this automatically, run: sudo setcap cap_sys_admin+ep '%s'\n", server_filepath);
-                else
-                    fprintf(stderr, "gsr info: gsr_kms_client_init: failed to get cap\n");
+                //fprintf(stderr, "No permission:(\n");
             }
+            cap_free(kms_server_cap);
+        } else if(!inside_flatpak) {
+            if(errno == ENODATA)
+                fprintf(stderr, "gsr info: gsr_kms_client_init: gsr-kms-server is missing sys_admin cap and will require root authentication. To bypass this automatically, run: sudo setcap cap_sys_admin+ep '%s'\n", server_filepath);
+            else
+                fprintf(stderr, "gsr info: gsr_kms_client_init: failed to get cap\n");
         }
     }
 
@@ -229,8 +281,13 @@ int gsr_kms_client_init(gsr_kms_client *self, const char *card_path) {
     }
 
     local_addr.sun_family = AF_UNIX;
-    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) {
+    snprintf(local_addr.sun_path, sizeof(local_addr.sun_path), "%s", (const char*)self->initial_socket_path);
+
+    const mode_t prev_mask = umask(0000);
+    const int bind_res = bind(self->initial_socket_fd, (struct sockaddr*)&local_addr, sizeof(local_addr.sun_family) + strlen(local_addr.sun_path));
+    umask(prev_mask);
+
+    if(bind_res == -1) {
         fprintf(stderr, "gsr error: gsr_kms_client_init: failed to bind socket, error: %s\n", strerror(errno));
         goto err;
     }
@@ -246,7 +303,7 @@ 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->initial_socket_path, card_path, NULL };
+            const char *args[] = { "flatpak-spawn", "--host", "/var/lib/flatpak/app/com.dec05eba.gpu_screen_recorder/current/active/files/bin/kms-server-proxy", self->initial_socket_path, card_path, home, NULL };
             execvp(args[0], (char *const*)args);
         } else if(has_perm) {
             const char *args[] = { server_filepath, self->initial_socket_path, card_path, NULL };
@@ -262,17 +319,14 @@ int gsr_kms_client_init(gsr_kms_client *self, const char *card_path) {
     }
 
     fprintf(stderr, "gsr info: gsr_kms_client_init: waiting for server to connect\n");
+    struct pollfd poll_fd = {
+        .fd = self->initial_socket_fd,
+        .events = POLLIN,
+        .revents = 0
+    };
     for(;;) {
-        struct timeval tv;
-        fd_set rfds;
-        FD_ZERO(&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->initial_socket_fd, &rfds, NULL, NULL, &tv);
-        if(select_res > 0) {
+        int poll_res = poll(&poll_fd, 1, 100);
+        if(poll_res > 0 && (poll_fd.revents & POLLIN)) {
             socklen_t sock_len = 0;
             self->initial_client_fd = accept(self->initial_socket_fd, (struct sockaddr*)&remote_addr, &sock_len);
             if(self->initial_client_fd == -1) {
@@ -312,12 +366,12 @@ int gsr_kms_client_init(gsr_kms_client *self, const char *card_path) {
 }
 
 void cleanup_socket(gsr_kms_client *self, bool kill_server) {
-    if(self->initial_client_fd != -1) {
+    if(self->initial_client_fd > 0) {
         close(self->initial_client_fd);
         self->initial_client_fd = -1;
     }
 
-    if(self->initial_socket_fd != -1) {
+    if(self->initial_socket_fd > 0) {
         close(self->initial_socket_fd);
         self->initial_socket_fd = -1;
     }
@@ -331,8 +385,10 @@ void cleanup_socket(gsr_kms_client *self, bool kill_server) {
         }
     }
 
-    if(kill_server && self->kms_server_pid != -1) {
+    if(kill_server && self->kms_server_pid > 0) {
         kill(self->kms_server_pid, SIGKILL);
+        //int status;
+        //waitpid(self->kms_server_pid, &status, 0);
         self->kms_server_pid = -1;
     }
 
@@ -361,7 +417,7 @@ int gsr_kms_client_replace_connection(gsr_kms_client *self) {
         return -1;
     }
 
-    const int recv_res = recv_msg_from_server(self->socket_pair[GSR_SOCKET_PAIR_LOCAL], &response);
+    const int recv_res = recv_msg_from_server(self->kms_server_pid, self->socket_pair[GSR_SOCKET_PAIR_LOCAL], &response);
     if(recv_res == 0) {
         fprintf(stderr, "gsr warning: gsr_kms_client_replace_connection: kms server shut down\n");
         return -1;
@@ -371,7 +427,7 @@ int gsr_kms_client_replace_connection(gsr_kms_client *self) {
     }
 
     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);
+        fprintf(stderr, "gsr error: gsr_kms_client_replace_connection: expected gsr-kms-server protocol version to be %u, but it's %u. please reinstall gpu screen recorder\n", GSR_KMS_PROTOCOL_VERSION, response.version);
         /*close_fds(response);*/
         return -1;
     }
@@ -394,7 +450,7 @@ int gsr_kms_client_get_kms(gsr_kms_client *self, gsr_kms_response *response) {
         return -1;
     }
 
-    const int recv_res = recv_msg_from_server(self->socket_pair[GSR_SOCKET_PAIR_LOCAL], response);
+    const int recv_res = recv_msg_from_server(self->kms_server_pid, 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");
@@ -406,7 +462,7 @@ int gsr_kms_client_get_kms(gsr_kms_client *self, gsr_kms_response *response) {
     }
 
     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);
+        fprintf(stderr, "gsr error: gsr_kms_client_get_kms: expected gsr-kms-server protocol version to be %u, but it's %u. please reinstall gpu screen recorder\n", GSR_KMS_PROTOCOL_VERSION, response->version);
         /*close_fds(response);*/
         strcpy(response->err_msg, "mismatching protocol version");
         return -1;