| 1 | /* |
| 2 | * Noise generation for PuTTY's cryptographic random number |
| 3 | * generator. |
| 4 | */ |
| 5 | |
| 6 | #include <windows.h> |
| 7 | #include <stdio.h> |
| 8 | |
| 9 | #include "putty.h" |
| 10 | #include "ssh.h" |
| 11 | |
| 12 | static char seedpath[2*MAX_PATH+10] = "\0"; |
| 13 | |
| 14 | /* |
| 15 | * Find the random seed file path and store it in `seedpath'. |
| 16 | */ |
| 17 | static void get_seedpath(void) { |
| 18 | HKEY rkey; |
| 19 | DWORD type, size; |
| 20 | |
| 21 | size = sizeof(seedpath); |
| 22 | |
| 23 | if (RegOpenKey(HKEY_CURRENT_USER, PUTTY_REG_POS, &rkey)==ERROR_SUCCESS) { |
| 24 | int ret = RegQueryValueEx(rkey, "RandSeedFile", |
| 25 | 0, &type, seedpath, &size); |
| 26 | if (ret != ERROR_SUCCESS || type != REG_SZ) |
| 27 | seedpath[0] = '\0'; |
| 28 | RegCloseKey(rkey); |
| 29 | } else |
| 30 | seedpath[0] = '\0'; |
| 31 | |
| 32 | if (!seedpath[0]) { |
| 33 | int len, ret; |
| 34 | |
| 35 | len = GetEnvironmentVariable("HOMEDRIVE", seedpath, sizeof(seedpath)); |
| 36 | ret = GetEnvironmentVariable("HOMEPATH", seedpath+len, |
| 37 | sizeof(seedpath)-len); |
| 38 | if (ret == 0) { /* probably win95; store in \WINDOWS */ |
| 39 | GetWindowsDirectory(seedpath, sizeof(seedpath)); |
| 40 | len = strlen(seedpath); |
| 41 | } else |
| 42 | len += ret; |
| 43 | strcpy(seedpath+len, "\\PUTTY.RND"); |
| 44 | } |
| 45 | } |
| 46 | |
| 47 | /* |
| 48 | * This function is called once, at PuTTY startup, and will do some |
| 49 | * seriously silly things like listing directories and getting disk |
| 50 | * free space and a process snapshot. |
| 51 | */ |
| 52 | |
| 53 | void noise_get_heavy(void (*func) (void *, int)) { |
| 54 | HANDLE srch; |
| 55 | HANDLE seedf; |
| 56 | WIN32_FIND_DATA finddata; |
| 57 | char winpath[MAX_PATH+3]; |
| 58 | |
| 59 | GetWindowsDirectory(winpath, sizeof(winpath)); |
| 60 | strcat(winpath, "\\*"); |
| 61 | srch = FindFirstFile(winpath, &finddata); |
| 62 | if (srch != INVALID_HANDLE_VALUE) { |
| 63 | do { |
| 64 | func(&finddata, sizeof(finddata)); |
| 65 | } while (FindNextFile(srch, &finddata)); |
| 66 | FindClose(srch); |
| 67 | } |
| 68 | |
| 69 | if (!seedpath[0]) |
| 70 | get_seedpath(); |
| 71 | |
| 72 | seedf = CreateFile(seedpath, GENERIC_READ, |
| 73 | FILE_SHARE_READ | FILE_SHARE_WRITE, |
| 74 | NULL, OPEN_EXISTING, 0, NULL); |
| 75 | |
| 76 | if (seedf != INVALID_HANDLE_VALUE) { |
| 77 | while (1) { |
| 78 | char buf[1024]; |
| 79 | DWORD len; |
| 80 | |
| 81 | if (ReadFile(seedf, buf, sizeof(buf), &len, NULL) && len) |
| 82 | func(buf, len); |
| 83 | else |
| 84 | break; |
| 85 | } |
| 86 | CloseHandle(seedf); |
| 87 | } |
| 88 | } |
| 89 | |
| 90 | void random_save_seed(void) { |
| 91 | HANDLE seedf; |
| 92 | |
| 93 | if (!seedpath[0]) |
| 94 | get_seedpath(); |
| 95 | |
| 96 | seedf = CreateFile(seedpath, GENERIC_WRITE, 0, |
| 97 | NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL); |
| 98 | |
| 99 | if (seedf != INVALID_HANDLE_VALUE) { |
| 100 | int len; |
| 101 | DWORD lenwritten; |
| 102 | void *data; |
| 103 | |
| 104 | random_get_savedata(&data, &len); |
| 105 | WriteFile(seedf, data, len, &lenwritten, NULL); |
| 106 | CloseHandle(seedf); |
| 107 | } |
| 108 | } |
| 109 | |
| 110 | /* |
| 111 | * This function is called every time the random pool needs |
| 112 | * stirring, and will acquire the system time in all available |
| 113 | * forms and the battery status. |
| 114 | */ |
| 115 | void noise_get_light(void (*func) (void *, int)) { |
| 116 | SYSTEMTIME systime; |
| 117 | DWORD adjust[2]; |
| 118 | BOOL rubbish; |
| 119 | SYSTEM_POWER_STATUS pwrstat; |
| 120 | |
| 121 | GetSystemTime(&systime); |
| 122 | func(&systime, sizeof(systime)); |
| 123 | |
| 124 | GetSystemTimeAdjustment(&adjust[0], &adjust[1], &rubbish); |
| 125 | func(&adjust, sizeof(adjust)); |
| 126 | |
| 127 | #ifndef WIN32S_COMPAT |
| 128 | if (GetSystemPowerStatus(&pwrstat)) |
| 129 | func(&pwrstat, sizeof(pwrstat)); |
| 130 | #endif |
| 131 | } |
| 132 | |
| 133 | /* |
| 134 | * This function is called on every keypress or mouse move, and |
| 135 | * will add the current Windows time and performance monitor |
| 136 | * counter to the noise pool. It gets the scan code or mouse |
| 137 | * position passed in. |
| 138 | */ |
| 139 | void noise_ultralight(DWORD data) { |
| 140 | DWORD wintime; |
| 141 | LARGE_INTEGER perftime; |
| 142 | |
| 143 | random_add_noise(&data, sizeof(DWORD)); |
| 144 | |
| 145 | wintime = GetTickCount(); |
| 146 | random_add_noise(&wintime, sizeof(DWORD)); |
| 147 | |
| 148 | if (QueryPerformanceCounter(&perftime)) |
| 149 | random_add_noise(&perftime, sizeof(perftime)); |
| 150 | } |