| 1 | /* |
| 2 | * Noise generation for PuTTY's cryptographic random number |
| 3 | * generator. |
| 4 | */ |
| 5 | |
| 6 | #include <Types.h> |
| 7 | #include <Timer.h> |
| 8 | |
| 9 | #include "putty.h" |
| 10 | #include "ssh.h" |
| 11 | #include "storage.h" |
| 12 | |
| 13 | /* |
| 14 | * This function is called once, at PuTTY startup, and will do some |
| 15 | * seriously silly things like listing directories and getting disk |
| 16 | * free space and a process snapshot. |
| 17 | */ |
| 18 | |
| 19 | void noise_get_heavy(void (*func) (void *, int)) |
| 20 | { |
| 21 | |
| 22 | read_random_seed(func); |
| 23 | /* Update the seed immediately, in case another instance uses it. */ |
| 24 | random_save_seed(); |
| 25 | } |
| 26 | |
| 27 | void random_save_seed(void) |
| 28 | { |
| 29 | int len; |
| 30 | void *data; |
| 31 | |
| 32 | if (random_active) { |
| 33 | random_get_savedata(&data, &len); |
| 34 | write_random_seed(data, len); |
| 35 | sfree(data); |
| 36 | } |
| 37 | } |
| 38 | |
| 39 | /* |
| 40 | * This function is called every time the random pool needs |
| 41 | * stirring, and will acquire the system time. |
| 42 | */ |
| 43 | void noise_get_light(void (*func) (void *, int)) |
| 44 | { |
| 45 | UnsignedWide utc; |
| 46 | |
| 47 | Microseconds(&utc); |
| 48 | func(&utc, sizeof(utc)); |
| 49 | } |
| 50 | |
| 51 | /* |
| 52 | * This function is called on every keypress or mouse move, and |
| 53 | * will add the current time to the noise pool. It gets the scan |
| 54 | * code or mouse position passed in, and adds that too. |
| 55 | */ |
| 56 | void noise_ultralight(unsigned long data) |
| 57 | { |
| 58 | UnsignedWide utc; |
| 59 | |
| 60 | Microseconds(&utc); |
| 61 | random_add_noise(&utc, sizeof(utc)); |
| 62 | random_add_noise(&data, sizeof(data)); |
| 63 | } |
| 64 | |
| 65 | /* |
| 66 | * Local Variables: |
| 67 | * c-file-style: "simon" |
| 68 | * End: |
| 69 | */ |