- int ret;
- HANDLE hin;
- DWORD savemode, i;
-
- static const char absentmsg[] =
- "The server's host key is not cached in the registry. You\n"
- "have no guarantee that the server is the computer you\n"
- "think it is.\n"
- "The server's key fingerprint is:\n"
- "%s\n"
- "If you trust this host, enter \"y\" to add the key to\n"
- "PuTTY's cache and carry on connecting.\n"
- "If you do not trust this host, enter \"n\" to abandon the\n"
- "connection.\n" "Continue connecting? (y/n) ";
-
- static const char wrongmsg[] =
- "WARNING - POTENTIAL SECURITY BREACH!\n"
- "The server's host key does not match the one PuTTY has\n"
- "cached in the registry. This means that either the\n"
- "server administrator has changed the host key, or you\n"
- "have actually connected to another computer pretending\n"
- "to be the server.\n"
- "The new key fingerprint is:\n"
- "%s\n"
- "If you were expecting this change and trust the new key,\n"
- "enter \"y\" to update PuTTY's cache and continue connecting.\n"
- "If you want to carry on connecting but without updating\n"
- "the cache, enter \"n\".\n"
- "If you want to abandon the connection completely, press\n"
- "Return to cancel. Pressing Return is the ONLY guaranteed\n"
- "safe choice.\n"
- "Update cached key? (y/n, Return cancels connection) ";
-
- static const char abandoned[] = "Connection abandoned.\n";
-
- char line[32];
-
- /*
- * Verify the key against the registry.
- */
- ret = verify_host_key(host, port, keytype, keystr);
-
- if (ret == 0) /* success - key matched OK */
- return;
-
- if (ret == 2) { /* key was different */
- fprintf(stderr, wrongmsg, fingerprint);
- fflush(stderr);
- }
- if (ret == 1) { /* key was absent */
- fprintf(stderr, absentmsg, fingerprint);
- fflush(stderr);
- }
-
- hin = GetStdHandle(STD_INPUT_HANDLE);
- GetConsoleMode(hin, &savemode);
- SetConsoleMode(hin, (savemode | ENABLE_ECHO_INPUT |
- ENABLE_PROCESSED_INPUT | ENABLE_LINE_INPUT));
- ReadFile(hin, line, sizeof(line) - 1, &i, NULL);
- SetConsoleMode(hin, savemode);
-
- if (ret == 2) { /* key was different */
- if (line[0] != '\0' && line[0] != '\r' && line[0] != '\n') {
- if (line[0] == 'y' || line[0] == 'Y')
- store_host_key(host, port, keytype, keystr);
- } else {
- fprintf(stderr, abandoned);
- exit(0);
- }
- }
- if (ret == 1) { /* key was absent */
- if (line[0] == 'y' || line[0] == 'Y')
- store_host_key(host, port, keytype, keystr);
- else {
- fprintf(stderr, abandoned);
- exit(0);
- }
- }