16 static random_fn random_generate;
17 static bool_t random_generate(void *data, uint32_t bytes, uint8_t *buff)
19 struct rgen_data *st=data;
22 r= read(st->fd,buff,bytes);
25 /* This is totally crap error checking, but AFAICT many callers of
26 * this function do not check the return value. This is a minimal
27 * change to make the code not fail silently-but-insecurely.
29 * A proper fix requires either:
30 * - Declare all random number generation failures as fatal
31 * errors, and make this return void, and fix all callers,
32 * and make this call some appropriate function if it fails.
33 * - Make this have proper error checking (and reporting!)
34 * and make all callers check the error (and report!);
35 * this will be tricky, I think, because you have to report
36 * the errno somewhere.
38 * There's also the issue that this is only one possible
39 * implementation of a random number source; others may not rely
40 * on reading from a file descriptor, and may not produce
41 * appropriate settings of errno.
47 static list_t *random_apply(closure_t *self, struct cloc loc,
48 dict_t *context, list_t *args)
52 string_t filename=NULL;
54 st=safe_malloc(sizeof(*st),"random_apply");
56 st->cl.description="randomsource";
57 st->cl.type=CL_RANDOMSRC;
59 st->cl.interface=&st->ops;
61 st->ops.blocking=False;
62 st->ops.generate=random_generate;
65 arg1=list_elem(args,0);
66 arg2=list_elem(args,1);
69 cfgfatal(loc,"randomsource","requires a filename\n");
71 if (arg1->type != t_string) {
72 cfgfatal(arg1->loc,"randomsource",
73 "filename (arg1) must be a string\n");
75 filename=arg1->data.string;
78 if (arg2->type != t_bool) {
79 cfgfatal(arg2->loc,"randomsource",
80 "blocking parameter (arg2) must be bool\n");
82 st->ops.blocking=arg2->data.bool;
86 cfgfatal(loc,"randomsource","requires a filename\n");
88 st->fd=open(filename,O_RDONLY);
90 fatal_perror("randomsource (%s:%d): cannot open %s",arg1->loc.file,
91 arg1->loc.line,filename);
93 return new_closure(&st->cl);
96 void random_module(dict_t *d)
98 add_closure(d,"randomfile",random_apply);