kc3-lang/libressl/tests/pidwraptest.c

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• Hash : eb26e56b
  Author :
  Date : 2014-10-22T13:06:36
  

  undef LIBRESSL_INTERNAL for the pidwrap test.
  

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• tests/pidwraptest.c

• /*
   * Checks if LibreSSL's PRNG is fork-safe.
   * From https://www.agwa.name/blog/post/libressls_prng_is_unsafe_on_linux
   * This code is in the public domain.
   *
   * Original source: https://gist.github.com/AGWA/eb84e55ca25a7da1deb0
   */
  
  #undef LIBRESSL_INTERNAL
  #include <openssl/rand.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <unistd.h>
  #include <sys/wait.h>
  
  static void random_bytes (unsigned char* p, size_t len)
  {
  	if (RAND_bytes(p, len) != 1) {
  		fprintf(stderr, "RAND_bytes failed\n");
  		abort();
  	}
  }
  
  static void random_stir (void)
  {
  	if (RAND_poll() != 1) {
  		fprintf(stderr, "RAND_poll failed\n");
  		abort();
  	}
  }
  
  static void print_buffer (unsigned char* p, size_t len)
  {
  	while (len--) {
  		printf("%02x", (unsigned int)*p++);
  	}
  }
  
  int main ()
  {
  	char c = 0;
  	int	pipefd[2];
  	pipe(pipefd);
  	setbuf(stdout, NULL);
  
  	if (fork() == 0) {
  		unsigned char buffer[32];
  		pid_t grandparent_pid = getpid();
  
  		random_bytes(buffer, sizeof(buffer));
  
  		if (fork() == 0) {
  			random_stir();
  			setsid();
  			while (1) {
  				pid_t	grandchild_pid = fork();
  				if (grandchild_pid == 0) {
  					random_stir();
  					if (getpid() == grandparent_pid) {
  						random_bytes(buffer, sizeof(buffer));
  						print_buffer(buffer, sizeof(buffer));
  						printf("\n");
  					}
  					_exit(0);
  				}
  				wait(NULL);
  				if (grandchild_pid == grandparent_pid) {
  					break;
  				}
  			}
  			write(pipefd[1], &c, 1);
  			_exit(0);
  		}
  
  		random_bytes(buffer, sizeof(buffer));
  		print_buffer(buffer, sizeof(buffer));
  		printf(" ");
  		_exit(0);
  	}
  	wait(NULL);
  	close(pipefd[1]);
  	read(pipefd[0], &c, 1);
  	return 0;
  }
  
  

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