| 1 | /* |
| 2 | * winmisc.c: miscellaneous Windows-specific things |
| 3 | */ |
| 4 | |
| 5 | #include <stdio.h> |
| 6 | #include <stdlib.h> |
| 7 | #include "putty.h" |
| 8 | #include <security.h> |
| 9 | |
| 10 | OSVERSIONINFO osVersion; |
| 11 | |
| 12 | char *platform_get_x_display(void) { |
| 13 | /* We may as well check for DISPLAY in case it's useful. */ |
| 14 | return dupstr(getenv("DISPLAY")); |
| 15 | } |
| 16 | |
| 17 | Filename filename_from_str(const char *str) |
| 18 | { |
| 19 | Filename ret; |
| 20 | strncpy(ret.path, str, sizeof(ret.path)); |
| 21 | ret.path[sizeof(ret.path)-1] = '\0'; |
| 22 | return ret; |
| 23 | } |
| 24 | |
| 25 | const char *filename_to_str(const Filename *fn) |
| 26 | { |
| 27 | return fn->path; |
| 28 | } |
| 29 | |
| 30 | int filename_equal(Filename f1, Filename f2) |
| 31 | { |
| 32 | return !strcmp(f1.path, f2.path); |
| 33 | } |
| 34 | |
| 35 | int filename_is_null(Filename fn) |
| 36 | { |
| 37 | return !*fn.path; |
| 38 | } |
| 39 | |
| 40 | char *get_username(void) |
| 41 | { |
| 42 | DWORD namelen; |
| 43 | char *user; |
| 44 | int got_username = FALSE; |
| 45 | DECL_WINDOWS_FUNCTION(static, BOOLEAN, GetUserNameExA, |
| 46 | (EXTENDED_NAME_FORMAT, LPSTR, PULONG)); |
| 47 | |
| 48 | { |
| 49 | static int tried_usernameex = FALSE; |
| 50 | if (!tried_usernameex) { |
| 51 | /* Not available on Win9x, so load dynamically */ |
| 52 | HMODULE secur32 = load_system32_dll("secur32.dll"); |
| 53 | GET_WINDOWS_FUNCTION(secur32, GetUserNameExA); |
| 54 | tried_usernameex = TRUE; |
| 55 | } |
| 56 | } |
| 57 | |
| 58 | if (p_GetUserNameExA) { |
| 59 | /* |
| 60 | * If available, use the principal -- this avoids the problem |
| 61 | * that the local username is case-insensitive but Kerberos |
| 62 | * usernames are case-sensitive. |
| 63 | */ |
| 64 | |
| 65 | /* Get the length */ |
| 66 | namelen = 0; |
| 67 | (void) p_GetUserNameExA(NameUserPrincipal, NULL, &namelen); |
| 68 | |
| 69 | user = snewn(namelen, char); |
| 70 | got_username = p_GetUserNameExA(NameUserPrincipal, user, &namelen); |
| 71 | if (got_username) { |
| 72 | char *p = strchr(user, '@'); |
| 73 | if (p) *p = 0; |
| 74 | } else { |
| 75 | sfree(user); |
| 76 | } |
| 77 | } |
| 78 | |
| 79 | if (!got_username) { |
| 80 | /* Fall back to local user name */ |
| 81 | namelen = 0; |
| 82 | if (GetUserName(NULL, &namelen) == FALSE) { |
| 83 | /* |
| 84 | * Apparently this doesn't work at least on Windows XP SP2. |
| 85 | * Thus assume a maximum of 256. It will fail again if it |
| 86 | * doesn't fit. |
| 87 | */ |
| 88 | namelen = 256; |
| 89 | } |
| 90 | |
| 91 | user = snewn(namelen, char); |
| 92 | got_username = GetUserName(user, &namelen); |
| 93 | if (!got_username) { |
| 94 | sfree(user); |
| 95 | } |
| 96 | } |
| 97 | |
| 98 | return got_username ? user : NULL; |
| 99 | } |
| 100 | |
| 101 | BOOL init_winver(void) |
| 102 | { |
| 103 | ZeroMemory(&osVersion, sizeof(osVersion)); |
| 104 | osVersion.dwOSVersionInfoSize = sizeof (OSVERSIONINFO); |
| 105 | return GetVersionEx ( (OSVERSIONINFO *) &osVersion); |
| 106 | } |
| 107 | |
| 108 | HMODULE load_system32_dll(const char *libname) |
| 109 | { |
| 110 | /* |
| 111 | * Wrapper function to load a DLL out of c:\windows\system32 |
| 112 | * without going through the full DLL search path. (Hence no |
| 113 | * attack is possible by placing a substitute DLL earlier on that |
| 114 | * path.) |
| 115 | */ |
| 116 | static char *sysdir = NULL; |
| 117 | char *fullpath; |
| 118 | HMODULE ret; |
| 119 | |
| 120 | if (!sysdir) { |
| 121 | int size = 0, len; |
| 122 | do { |
| 123 | size = 3*size/2 + 512; |
| 124 | sysdir = sresize(sysdir, size, char); |
| 125 | len = GetSystemDirectory(sysdir, size); |
| 126 | } while (len >= size); |
| 127 | } |
| 128 | |
| 129 | fullpath = dupcat(sysdir, "\\", libname, NULL); |
| 130 | ret = LoadLibrary(fullpath); |
| 131 | sfree(fullpath); |
| 132 | return ret; |
| 133 | } |
| 134 | |
| 135 | #ifdef DEBUG |
| 136 | static FILE *debug_fp = NULL; |
| 137 | static HANDLE debug_hdl = INVALID_HANDLE_VALUE; |
| 138 | static int debug_got_console = 0; |
| 139 | |
| 140 | void dputs(char *buf) |
| 141 | { |
| 142 | DWORD dw; |
| 143 | |
| 144 | if (!debug_got_console) { |
| 145 | if (AllocConsole()) { |
| 146 | debug_got_console = 1; |
| 147 | debug_hdl = GetStdHandle(STD_OUTPUT_HANDLE); |
| 148 | } |
| 149 | } |
| 150 | if (!debug_fp) { |
| 151 | debug_fp = fopen("debug.log", "w"); |
| 152 | } |
| 153 | |
| 154 | if (debug_hdl != INVALID_HANDLE_VALUE) { |
| 155 | WriteFile(debug_hdl, buf, strlen(buf), &dw, NULL); |
| 156 | } |
| 157 | fputs(buf, debug_fp); |
| 158 | fflush(debug_fp); |
| 159 | } |
| 160 | #endif |
| 161 | |
| 162 | #ifdef MINEFIELD |
| 163 | /* |
| 164 | * Minefield - a Windows equivalent for Electric Fence |
| 165 | */ |
| 166 | |
| 167 | #define PAGESIZE 4096 |
| 168 | |
| 169 | /* |
| 170 | * Design: |
| 171 | * |
| 172 | * We start by reserving as much virtual address space as Windows |
| 173 | * will sensibly (or not sensibly) let us have. We flag it all as |
| 174 | * invalid memory. |
| 175 | * |
| 176 | * Any allocation attempt is satisfied by committing one or more |
| 177 | * pages, with an uncommitted page on either side. The returned |
| 178 | * memory region is jammed up against the _end_ of the pages. |
| 179 | * |
| 180 | * Freeing anything causes instantaneous decommitment of the pages |
| 181 | * involved, so stale pointers are caught as soon as possible. |
| 182 | */ |
| 183 | |
| 184 | static int minefield_initialised = 0; |
| 185 | static void *minefield_region = NULL; |
| 186 | static long minefield_size = 0; |
| 187 | static long minefield_npages = 0; |
| 188 | static long minefield_curpos = 0; |
| 189 | static unsigned short *minefield_admin = NULL; |
| 190 | static void *minefield_pages = NULL; |
| 191 | |
| 192 | static void minefield_admin_hide(int hide) |
| 193 | { |
| 194 | int access = hide ? PAGE_NOACCESS : PAGE_READWRITE; |
| 195 | VirtualProtect(minefield_admin, minefield_npages * 2, access, NULL); |
| 196 | } |
| 197 | |
| 198 | static void minefield_init(void) |
| 199 | { |
| 200 | int size; |
| 201 | int admin_size; |
| 202 | int i; |
| 203 | |
| 204 | for (size = 0x40000000; size > 0; size = ((size >> 3) * 7) & ~0xFFF) { |
| 205 | minefield_region = VirtualAlloc(NULL, size, |
| 206 | MEM_RESERVE, PAGE_NOACCESS); |
| 207 | if (minefield_region) |
| 208 | break; |
| 209 | } |
| 210 | minefield_size = size; |
| 211 | |
| 212 | /* |
| 213 | * Firstly, allocate a section of that to be the admin block. |
| 214 | * We'll need a two-byte field for each page. |
| 215 | */ |
| 216 | minefield_admin = minefield_region; |
| 217 | minefield_npages = minefield_size / PAGESIZE; |
| 218 | admin_size = (minefield_npages * 2 + PAGESIZE - 1) & ~(PAGESIZE - 1); |
| 219 | minefield_npages = (minefield_size - admin_size) / PAGESIZE; |
| 220 | minefield_pages = (char *) minefield_region + admin_size; |
| 221 | |
| 222 | /* |
| 223 | * Commit the admin region. |
| 224 | */ |
| 225 | VirtualAlloc(minefield_admin, minefield_npages * 2, |
| 226 | MEM_COMMIT, PAGE_READWRITE); |
| 227 | |
| 228 | /* |
| 229 | * Mark all pages as unused (0xFFFF). |
| 230 | */ |
| 231 | for (i = 0; i < minefield_npages; i++) |
| 232 | minefield_admin[i] = 0xFFFF; |
| 233 | |
| 234 | /* |
| 235 | * Hide the admin region. |
| 236 | */ |
| 237 | minefield_admin_hide(1); |
| 238 | |
| 239 | minefield_initialised = 1; |
| 240 | } |
| 241 | |
| 242 | static void minefield_bomb(void) |
| 243 | { |
| 244 | div(1, *(int *) minefield_pages); |
| 245 | } |
| 246 | |
| 247 | static void *minefield_alloc(int size) |
| 248 | { |
| 249 | int npages; |
| 250 | int pos, lim, region_end, region_start; |
| 251 | int start; |
| 252 | int i; |
| 253 | |
| 254 | npages = (size + PAGESIZE - 1) / PAGESIZE; |
| 255 | |
| 256 | minefield_admin_hide(0); |
| 257 | |
| 258 | /* |
| 259 | * Search from current position until we find a contiguous |
| 260 | * bunch of npages+2 unused pages. |
| 261 | */ |
| 262 | pos = minefield_curpos; |
| 263 | lim = minefield_npages; |
| 264 | while (1) { |
| 265 | /* Skip over used pages. */ |
| 266 | while (pos < lim && minefield_admin[pos] != 0xFFFF) |
| 267 | pos++; |
| 268 | /* Count unused pages. */ |
| 269 | start = pos; |
| 270 | while (pos < lim && pos - start < npages + 2 && |
| 271 | minefield_admin[pos] == 0xFFFF) |
| 272 | pos++; |
| 273 | if (pos - start == npages + 2) |
| 274 | break; |
| 275 | /* If we've reached the limit, reset the limit or stop. */ |
| 276 | if (pos >= lim) { |
| 277 | if (lim == minefield_npages) { |
| 278 | /* go round and start again at zero */ |
| 279 | lim = minefield_curpos; |
| 280 | pos = 0; |
| 281 | } else { |
| 282 | minefield_admin_hide(1); |
| 283 | return NULL; |
| 284 | } |
| 285 | } |
| 286 | } |
| 287 | |
| 288 | minefield_curpos = pos - 1; |
| 289 | |
| 290 | /* |
| 291 | * We have npages+2 unused pages starting at start. We leave |
| 292 | * the first and last of these alone and use the rest. |
| 293 | */ |
| 294 | region_end = (start + npages + 1) * PAGESIZE; |
| 295 | region_start = region_end - size; |
| 296 | /* FIXME: could align here if we wanted */ |
| 297 | |
| 298 | /* |
| 299 | * Update the admin region. |
| 300 | */ |
| 301 | for (i = start + 2; i < start + npages + 1; i++) |
| 302 | minefield_admin[i] = 0xFFFE; /* used but no region starts here */ |
| 303 | minefield_admin[start + 1] = region_start % PAGESIZE; |
| 304 | |
| 305 | minefield_admin_hide(1); |
| 306 | |
| 307 | VirtualAlloc((char *) minefield_pages + region_start, size, |
| 308 | MEM_COMMIT, PAGE_READWRITE); |
| 309 | return (char *) minefield_pages + region_start; |
| 310 | } |
| 311 | |
| 312 | static void minefield_free(void *ptr) |
| 313 | { |
| 314 | int region_start, i, j; |
| 315 | |
| 316 | minefield_admin_hide(0); |
| 317 | |
| 318 | region_start = (char *) ptr - (char *) minefield_pages; |
| 319 | i = region_start / PAGESIZE; |
| 320 | if (i < 0 || i >= minefield_npages || |
| 321 | minefield_admin[i] != region_start % PAGESIZE) |
| 322 | minefield_bomb(); |
| 323 | for (j = i; j < minefield_npages && minefield_admin[j] != 0xFFFF; j++) { |
| 324 | minefield_admin[j] = 0xFFFF; |
| 325 | } |
| 326 | |
| 327 | VirtualFree(ptr, j * PAGESIZE - region_start, MEM_DECOMMIT); |
| 328 | |
| 329 | minefield_admin_hide(1); |
| 330 | } |
| 331 | |
| 332 | static int minefield_get_size(void *ptr) |
| 333 | { |
| 334 | int region_start, i, j; |
| 335 | |
| 336 | minefield_admin_hide(0); |
| 337 | |
| 338 | region_start = (char *) ptr - (char *) minefield_pages; |
| 339 | i = region_start / PAGESIZE; |
| 340 | if (i < 0 || i >= minefield_npages || |
| 341 | minefield_admin[i] != region_start % PAGESIZE) |
| 342 | minefield_bomb(); |
| 343 | for (j = i; j < minefield_npages && minefield_admin[j] != 0xFFFF; j++); |
| 344 | |
| 345 | minefield_admin_hide(1); |
| 346 | |
| 347 | return j * PAGESIZE - region_start; |
| 348 | } |
| 349 | |
| 350 | void *minefield_c_malloc(size_t size) |
| 351 | { |
| 352 | if (!minefield_initialised) |
| 353 | minefield_init(); |
| 354 | return minefield_alloc(size); |
| 355 | } |
| 356 | |
| 357 | void minefield_c_free(void *p) |
| 358 | { |
| 359 | if (!minefield_initialised) |
| 360 | minefield_init(); |
| 361 | minefield_free(p); |
| 362 | } |
| 363 | |
| 364 | /* |
| 365 | * realloc _always_ moves the chunk, for rapid detection of code |
| 366 | * that assumes it won't. |
| 367 | */ |
| 368 | void *minefield_c_realloc(void *p, size_t size) |
| 369 | { |
| 370 | size_t oldsize; |
| 371 | void *q; |
| 372 | if (!minefield_initialised) |
| 373 | minefield_init(); |
| 374 | q = minefield_alloc(size); |
| 375 | oldsize = minefield_get_size(p); |
| 376 | memcpy(q, p, (oldsize < size ? oldsize : size)); |
| 377 | minefield_free(p); |
| 378 | return q; |
| 379 | } |
| 380 | |
| 381 | #endif /* MINEFIELD */ |