#include <unistd.h>
// Function which execs "am broadcast ..".
-void exec_am_broadcast(int argc, char** argv, char* input_address_string, char* output_address_string)
+_Noreturn void exec_am_broadcast(int argc, char** argv, char* input_address_string, char* output_address_string)
{
// Redirect stdout to /dev/null (but leave stderr open):
close(STDOUT_FILENO);
// Close stdin:
close(STDIN_FILENO);
- // The user is calculated from the uid in android.os.UserHandle#getUserId(int uid) as "uid / 100000", so we do the same:
- uid_t current_uid = getuid();
- int android_user_id = current_uid / 100000;
- char* android_user_id_string;
- if (asprintf(&android_user_id_string, "%d", android_user_id) == -1) {
- fprintf(stderr, "asprintf() error");
- return;
- }
-
int const extra_args = 15; // Including ending NULL.
char** child_argv = malloc((sizeof(char*)) * (argc + extra_args));
child_argv[0] = "am";
child_argv[1] = "broadcast";
child_argv[2] = "--user";
- child_argv[3] = android_user_id_string;
+ child_argv[3] = "0";
child_argv[4] = "-n";
child_argv[5] = "com.termux.api/.TermuxApiReceiver";
child_argv[6] = "--es";
child_argv[argc + extra_args] = NULL;
// Use an a executable taking care of PATH and LD_LIBRARY_PATH:
- char const* const am_executable = "/data/data/com.termux/files/usr/bin/am";
- execv(am_executable, child_argv);
+ execv("/data/data/com.termux/files/usr/bin/am", child_argv);
- perror("execv(\"/system/bin/am\")");
+ perror("execv(\"/data/data/com.termux/files/usr/bin/am\")");
exit(1);
}
void generate_uuid(char* str) {
- sprintf(str, "%x%x-%x-%x-%x-%x%x%x",
- rand(), rand(), // Generates a 64-bit Hex number
- (uint32_t) getpid(), // Generates a 32-bit Hex number
- ((rand() & 0x0fff) | 0x4000), // Generates a 32-bit Hex number of the form 4xxx (4 indicates the UUID version)
- rand() % 0x3fff + 0x8000, // Generates a 32-bit Hex number in the range [0x8000, 0xbfff]
- rand(), rand(), rand()); // Generates a 96-bit Hex number
+ sprintf(str, "%x%x-%x-%x-%x-%x%x%x",
+ arc4random(), arc4random(), // Generates a 64-bit Hex number
+ (uint32_t) getpid(), // Generates a 32-bit Hex number
+ ((arc4random() & 0x0fff) | 0x4000), // Generates a 32-bit Hex number of the form 4xxx (4 indicates the UUID version)
+ arc4random() % 0x3fff + 0x8000, // Generates a 32-bit Hex number in the range [0x8000, 0xbfff]
+ arc4random(), arc4random(), arc4random()); // Generates a 96-bit Hex number
}
// Thread function which reads from stdin and writes to socket.
socklen_t addrlen = sizeof(remote_addr);
int output_client_socket = accept(output_server_socket, (struct sockaddr*) &remote_addr, &addrlen);
- int len;
+ ssize_t len;
char buffer[1024];
- while (len = read(STDIN_FILENO, &buffer, sizeof(buffer)-1), len > 0) {
+ while (len = read(STDIN_FILENO, &buffer, sizeof(buffer)), len > 0) {
if (write(output_client_socket, buffer, len) < 0) break;
}
// Close output socket on end of input:
// Main thread function which reads from input socket and writes to stdout.
void transmit_socket_to_stdout(int input_socket_fd) {
- int len;
+ ssize_t len;
char buffer[1024];
- while ((len = read(input_socket_fd, &buffer, sizeof(buffer)-1)) > 0) {
- buffer[len] = 0;
+ while ((len = read(input_socket_fd, &buffer, sizeof(buffer))) > 0) {
write(STDOUT_FILENO, buffer, len);
}
if (len < 0) perror("read()");
char input_address_string[100]; // This program reads from it.
char output_address_string[100]; // This program writes to it.
- // Seed the random number generator:
- struct timeval time;
- gettimeofday(&time,NULL);
- srand((time.tv_sec * 1000) + (time.tv_usec / 1000));
-
generate_uuid(input_address_string);
generate_uuid(output_address_string);
pid_t fork_result = fork();
switch (fork_result) {
case -1: perror("fork()"); return 1;
- case 0: exec_am_broadcast(argc, argv, input_address_string, output_address_string); return 0;
+ case 0: exec_am_broadcast(argc, argv, input_address_string, output_address_string);
}
struct sockaddr_un remote_addr;