--- /dev/null
+/*
+ * Code for PuTTY to import and export private key files in other
+ * SSH clients' formats.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <ctype.h>
+
+#include "ssh.h"
+#include "misc.h"
+
+#define PUT_32BIT(cp, value) do { \
+ (cp)[3] = (value); \
+ (cp)[2] = (value) >> 8; \
+ (cp)[1] = (value) >> 16; \
+ (cp)[0] = (value) >> 24; } while (0)
+
+#define GET_32BIT(cp) \
+ (((unsigned long)(unsigned char)(cp)[0] << 24) | \
+ ((unsigned long)(unsigned char)(cp)[1] << 16) | \
+ ((unsigned long)(unsigned char)(cp)[2] << 8) | \
+ ((unsigned long)(unsigned char)(cp)[3]))
+
+int openssh_encrypted(char *filename);
+struct ssh2_userkey *openssh_read(char *filename, char *passphrase);
+
+/*
+ * Given a key type, determine whether we know how to import it.
+ */
+int import_possible(int type)
+{
+ if (type == SSH_KEYTYPE_OPENSSH)
+ return 1;
+ return 0;
+}
+
+/*
+ * Given a key type, determine what native key type
+ * (SSH_KEYTYPE_SSH1 or SSH_KEYTYPE_SSH2) it will come out as once
+ * we've imported it.
+ */
+int import_target_type(int type)
+{
+ /*
+ * There are no known foreign SSH1 key formats.
+ */
+ return SSH_KEYTYPE_SSH2;
+}
+
+/*
+ * Determine whether a foreign key is encrypted.
+ */
+int import_encrypted(char *filename, int type, char **comment)
+{
+ if (type == SSH_KEYTYPE_OPENSSH) {
+ *comment = filename; /* OpenSSH doesn't do key comments */
+ return openssh_encrypted(filename);
+ }
+ return 0;
+}
+
+/*
+ * Import an SSH1 key.
+ */
+int import_ssh1(char *filename, int type, struct RSAKey *key, char *passphrase)
+{
+ return 0;
+}
+
+/*
+ * Import an SSH2 key.
+ */
+struct ssh2_userkey *import_ssh2(char *filename, int type, char *passphrase)
+{
+ if (type == SSH_KEYTYPE_OPENSSH)
+ return openssh_read(filename, passphrase);
+ return NULL;
+}
+
+/* ----------------------------------------------------------------------
+ * Helper routines. (The base64 ones are defined in sshpubk.c.)
+ */
+
+#define isbase64(c) ( ((c) >= 'A' && (c) <= 'Z') || \
+ ((c) >= 'a' && (c) <= 'z') || \
+ ((c) >= '0' && (c) <= '9') || \
+ (c) == '+' || (c) == '/' || (c) == '=' \
+ )
+
+extern int base64_decode_atom(char *atom, unsigned char *out);
+extern int base64_lines(int datalen);
+extern void base64_encode_atom(unsigned char *data, int n, char *out);
+extern void base64_encode(FILE * fp, unsigned char *data, int datalen);
+
+/*
+ * Read an ASN.1/BER identifier and length pair.
+ *
+ * Flags are a combination of the #defines listed below.
+ *
+ * Returns -1 if unsuccessful; otherwise returns the number of
+ * bytes used out of the source data.
+ */
+
+/* ASN.1 tag classes. */
+#define ASN1_CLASS_UNIVERSAL (0 << 6)
+#define ASN1_CLASS_APPLICATION (1 << 6)
+#define ASN1_CLASS_CONTEXT_SPECIFIC (2 << 6)
+#define ASN1_CLASS_PRIVATE (3 << 6)
+#define ASN1_CLASS_MASK (3 << 6)
+
+/* Primitive versus constructed bit. */
+#define ASN1_CONSTRUCTED (1 << 5)
+
+int ber_read_id_len(void *source, int sourcelen,
+ int *id, int *length, int *flags)
+{
+ unsigned char *p = (unsigned char *) source;
+
+ if (sourcelen == 0)
+ return -1;
+
+ *flags = (*p & 0xE0);
+ if ((*p & 0x1F) == 0x1F) {
+ *id = 0;
+ while (*p & 0x80) {
+ *id = (*id << 7) | (*p & 0x7F);
+ p++, sourcelen--;
+ if (sourcelen == 0)
+ return -1;
+ }
+ *id = (*id << 7) | (*p & 0x7F);
+ p++, sourcelen--;
+ } else {
+ *id = *p & 0x1F;
+ p++, sourcelen--;
+ }
+
+ if (sourcelen == 0)
+ return -1;
+
+ if (*p & 0x80) {
+ int n = *p & 0x7F;
+ p++, sourcelen--;
+ if (sourcelen < n)
+ return -1;
+ *length = 0;
+ while (n--)
+ *length = (*length << 8) | (*p++);
+ sourcelen -= n;
+ } else {
+ *length = *p;
+ p++, sourcelen--;
+ }
+
+ return p - (unsigned char *) source;
+}
+
+/* ----------------------------------------------------------------------
+ * Code to read OpenSSH private keys.
+ */
+
+enum { OSSH_DSA, OSSH_RSA };
+struct openssh_key {
+ int type;
+ int encrypted;
+ char iv[32];
+ unsigned char *keyblob;
+ int keyblob_len, keyblob_size;
+};
+
+struct openssh_key *load_openssh_key(char *filename)
+{
+ struct openssh_key *ret;
+ FILE *fp;
+ char buffer[256];
+ char *errmsg, *p;
+ int headers_done;
+
+ ret = smalloc(sizeof(*ret));
+ ret->keyblob = NULL;
+ ret->keyblob_len = ret->keyblob_size = 0;
+ ret->encrypted = 0;
+ memset(ret->iv, 0, sizeof(ret->iv));
+
+ fp = fopen(filename, "r");
+ if (!fp) {
+ errmsg = "Unable to open key file";
+ goto error;
+ }
+ if (!fgets(buffer, sizeof(buffer), fp) ||
+ 0 != strncmp(buffer, "-----BEGIN ", 11) ||
+ 0 != strcmp(buffer+strlen(buffer)-17, "PRIVATE KEY-----\n")) {
+ errmsg = "File does not begin with OpenSSH key header";
+ goto error;
+ }
+ if (!strcmp(buffer, "-----BEGIN RSA PRIVATE KEY-----\n"))
+ ret->type = OSSH_RSA;
+ else if (!strcmp(buffer, "-----BEGIN DSA PRIVATE KEY-----\n"))
+ ret->type = OSSH_DSA;
+ else {
+ errmsg = "Unrecognised key type";
+ goto error;
+ }
+
+ headers_done = 0;
+ while (1) {
+ if (!fgets(buffer, sizeof(buffer), fp)) {
+ errmsg = "Unexpected end of file";
+ goto error;
+ }
+ if (0 == strncmp(buffer, "-----END ", 9) &&
+ 0 == strcmp(buffer+strlen(buffer)-17, "PRIVATE KEY-----\n"))
+ break; /* done */
+ if ((p = strchr(buffer, ':')) != NULL) {
+ if (headers_done) {
+ errmsg = "Header found in body of key data";
+ goto error;
+ }
+ *p++ = '\0';
+ while (*p && isspace((unsigned char)*p)) p++;
+ if (!strcmp(buffer, "Proc-Type")) {
+ if (p[0] != '4' || p[1] != ',') {
+ errmsg = "Proc-Type is not 4 (only 4 is supported)";
+ goto error;
+ }
+ p += 2;
+ if (!strcmp(p, "ENCRYPTED\n"))
+ ret->encrypted = 1;
+ } else if (!strcmp(buffer, "DEK-Info")) {
+ int i, j;
+
+ if (strncmp(p, "DES-EDE3-CBC,", 13)) {
+ errmsg = "Ciphers other than DES-EDE3-CBC not supported";
+ goto error;
+ }
+ p += 13;
+ for (i = 0; i < 8; i++) {
+ if (1 != sscanf(p, "%2x", &j))
+ break;
+ ret->iv[i] = j;
+ p += 2;
+ }
+ if (i < 8) {
+ errmsg = "Expected 16-digit iv in DEK-Info";
+ goto error;
+ }
+ }
+ } else {
+ headers_done = 1;
+
+ p = buffer;
+ while (isbase64(p[0]) && isbase64(p[1]) &&
+ isbase64(p[2]) && isbase64(p[3])) {
+ int len;
+ unsigned char out[3];
+
+ len = base64_decode_atom(p, out);
+
+ if (len <= 0) {
+ errmsg = "Invalid base64 encoding";
+ goto error;
+ }
+
+ if (ret->keyblob_len + len > ret->keyblob_size) {
+ ret->keyblob_size = ret->keyblob_len + len + 256;
+ ret->keyblob = srealloc(ret->keyblob, ret->keyblob_size);
+ }
+
+ memcpy(ret->keyblob + ret->keyblob_len, out, len);
+ ret->keyblob_len += len;
+
+ p += 4;
+ }
+
+ if (isbase64(*p)) {
+ errmsg = "base64 characters left at end of line";
+ goto error;
+ }
+ }
+ }
+
+ if (ret->keyblob_len == 0 || !ret->keyblob) {
+ errmsg = "Key body not present";
+ goto error;
+ }
+
+ if (ret->encrypted && ret->keyblob_len % 8 != 0) {
+ errmsg = "Encrypted key blob is not a multiple of cipher block size";
+ goto error;
+ }
+
+ return ret;
+
+ error:
+ if (ret) {
+ if (ret->keyblob) sfree(ret->keyblob);
+ sfree(ret);
+ }
+ return NULL;
+}
+
+int openssh_encrypted(char *filename)
+{
+ struct openssh_key *key = load_openssh_key(filename);
+ int ret;
+
+ if (!key)
+ return 0;
+ ret = key->encrypted;
+ sfree(key->keyblob);
+ sfree(key);
+ return ret;
+}
+
+struct ssh2_userkey *openssh_read(char *filename, char *passphrase)
+{
+ struct openssh_key *key = load_openssh_key(filename);
+ struct ssh2_userkey *retkey;
+ unsigned char *p;
+ int ret, id, len, flags;
+ int i, num_integers;
+ struct ssh2_userkey *retval = NULL;
+ char *errmsg;
+ unsigned char *blob;
+ int blobptr, privptr;
+ char *modptr;
+ int modlen;
+
+ if (!key)
+ return NULL;
+
+ if (key->encrypted) {
+ /*
+ * Derive encryption key from passphrase and iv/salt:
+ *
+ * - let block A equal MD5(passphrase || iv)
+ * - let block B equal MD5(A || passphrase || iv)
+ * - block C would be MD5(B || passphrase || iv) and so on
+ * - encryption key is the first N bytes of A || B
+ */
+ struct MD5Context md5c;
+ unsigned char keybuf[32];
+
+ MD5Init(&md5c);
+ MD5Update(&md5c, passphrase, strlen(passphrase));
+ MD5Update(&md5c, key->iv, 8);
+ MD5Final(keybuf, &md5c);
+
+ MD5Init(&md5c);
+ MD5Update(&md5c, keybuf, 16);
+ MD5Update(&md5c, passphrase, strlen(passphrase));
+ MD5Update(&md5c, key->iv, 8);
+ MD5Final(keybuf+16, &md5c);
+
+ /*
+ * Now decrypt the key blob.
+ */
+ des3_decrypt_pubkey_ossh(keybuf, key->iv,
+ key->keyblob, key->keyblob_len);
+ }
+
+ /*
+ * Now we have a decrypted key blob, which contains an ASN.1
+ * encoded private key. We must now untangle the ASN.1.
+ *
+ * We expect the whole key blob to be formatted as a SEQUENCE
+ * (0x30 followed by a length code indicating that the rest of
+ * the blob is part of the sequence). Within that SEQUENCE we
+ * expect to see a bunch of INTEGERs. What those integers mean
+ * depends on the key type:
+ *
+ * - For RSA, we expect the integers to be 0, n, e, d, p, q,
+ * dmp1, dmq1, iqmp in that order. (The last three are d mod
+ * (p-1), d mod (q-1), inverse of q mod p respectively.)
+ *
+ * - For DSA, we expect them to be 0, p, q, g, y, x in that
+ * order.
+ */
+
+ p = key->keyblob;
+
+ /* Expect the SEQUENCE header. Take its absence as a failure to decrypt. */
+ ret = ber_read_id_len(p, key->keyblob_len, &id, &len, &flags);
+ p += ret;
+ if (ret < 0 || id != 16) {
+ errmsg = "ASN.1 decoding failure";
+ retval = SSH2_WRONG_PASSPHRASE;
+ goto error;
+ }
+
+ /* Expect a load of INTEGERs. */
+ if (key->type == OSSH_RSA)
+ num_integers = 9;
+ else if (key->type == OSSH_DSA)
+ num_integers = 6;
+
+ /*
+ * Space to create key blob in.
+ */
+ blob = smalloc(256+key->keyblob_len);
+ PUT_32BIT(blob, 7);
+ if (key->type == OSSH_DSA)
+ memcpy(blob+4, "ssh-dss", 7);
+ else if (key->type == OSSH_RSA)
+ memcpy(blob+4, "ssh-rsa", 7);
+ blobptr = 4+7;
+ privptr = -1;
+
+ for (i = 0; i < num_integers; i++) {
+ ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p,
+ &id, &len, &flags);
+ p += ret;
+ if (ret < 0 || id != 2 ||
+ key->keyblob+key->keyblob_len-p < len) {
+ errmsg = "ASN.1 decoding failure";
+ goto error;
+ }
+
+ if (i == 0) {
+ /*
+ * The first integer should be zero always (I think
+ * this is some sort of version indication).
+ */
+ if (len != 1 || p[0] != 0) {
+ errmsg = "Version number mismatch";
+ goto error;
+ }
+ } else if (key->type == OSSH_RSA) {
+ /*
+ * Integers 1 and 2 go into the public blob but in the
+ * opposite order; integers 3, 4, 5 and 8 go into the
+ * private blob. The other two (6 and 7) are ignored.
+ */
+ if (i == 1) {
+ /* Save the details for after we deal with number 2. */
+ modptr = p;
+ modlen = len;
+ } else if (i != 6 && i != 7) {
+ PUT_32BIT(blob+blobptr, len);
+ memcpy(blob+blobptr+4, p, len);
+ blobptr += 4+len;
+ if (i == 2) {
+ PUT_32BIT(blob+blobptr, modlen);
+ memcpy(blob+blobptr+4, modptr, modlen);
+ blobptr += 4+modlen;
+ privptr = blobptr;
+ }
+ }
+ } else if (key->type == OSSH_DSA) {
+ /*
+ * Integers 1-4 go into the public blob; integer 5 goes
+ * into the private blob.
+ */
+ PUT_32BIT(blob+blobptr, len);
+ memcpy(blob+blobptr+4, p, len);
+ blobptr += 4+len;
+ if (i == 4)
+ privptr = blobptr;
+ }
+
+ /* Skip past the number. */
+ p += len;
+ }
+
+ /*
+ * Now put together the actual key. Simplest way to do this is
+ * to assemble our own key blobs and feed them to the createkey
+ * functions; this is a bit faffy but it does mean we get all
+ * the sanity checks for free.
+ */
+ assert(privptr > 0); /* should have bombed by now if not */
+ retkey = smalloc(sizeof(struct ssh2_userkey));
+ retkey->alg = (key->type == OSSH_RSA ? &ssh_rsa : &ssh_dss);
+ retkey->data = retkey->alg->createkey(blob, privptr,
+ blob+privptr, blobptr-privptr);
+ if (!retkey->data) {
+ sfree(retkey);
+ errmsg = "unable to create key data structure";
+ goto error;
+ }
+
+ retkey->comment = dupstr("imported-openssh-key");
+ if (blob) sfree(blob);
+ sfree(key->keyblob);
+ sfree(key);
+ return retkey;
+
+ error:
+ if (blob) sfree(blob);
+ sfree(key->keyblob);
+ sfree(key);
+ return retval;
+}
IDC_TYPESTATIC, IDC_KEYSSH1, IDC_KEYSSH2RSA, IDC_KEYSSH2DSA,
IDC_BITSSTATIC, IDC_BITS,
IDC_ABOUT,
+ IDC_GIVEHELP,
+ IDC_IMPORT, IDC_EXPORT_OPENSSH, IDC_EXPORT_SSHCOM
};
static const int nokey_ids[] = { IDC_NOKEY, 0 };
static const int generating_ids[] =
}
requested_help = FALSE;
+ {
+ HMENU menu, menu1;
+
+ menu = CreateMenu();
+
+ menu1 = CreateMenu();
+ AppendMenu(menu1, MF_ENABLED, IDC_GENERATE, "&Generate key pair");
+ AppendMenu(menu1, MF_ENABLED, IDC_LOAD, "&Load private key");
+ AppendMenu(menu1, MF_ENABLED, IDC_SAVEPUB, "Save p&ublic key");
+ AppendMenu(menu1, MF_ENABLED, IDC_SAVE, "&Save private key");
+
+ AppendMenu(menu, MF_POPUP | MF_ENABLED, (UINT) menu1, "&File");
+
+#if 0
+ /*
+ * Exporting not yet supported, but when we do it we
+ * should just put this lot back in.
+ */
+ menu1 = CreateMenu();
+ AppendMenu(menu1, MF_ENABLED, IDC_EXPORT_OPENSSH,
+ "Export &OpenSSH key");
+ AppendMenu(menu1, MF_ENABLED, IDC_EXPORT_SSHCOM,
+ "Export &ssh.com key");
+
+ AppendMenu(menu, MF_POPUP | MF_ENABLED, (UINT) menu1,
+ "&Export");
+#endif
+
+ menu1 = CreateMenu();
+ AppendMenu(menu1, MF_ENABLED, IDC_ABOUT, "&About");
+ if (help_path)
+ AppendMenu(menu1, MF_ENABLED, IDC_GIVEHELP, "&Help");
+
+ AppendMenu(menu, MF_POPUP | MF_ENABLED, (UINT) menu1, "&Help");
+
+ SetMenu(hwnd, menu);
+ }
+
/*
* Centre the window.
*/
/* Accelerators used: acglops1rbd */
ctlposinit(&cp, hwnd, 4, 4, 4);
- bartitle(&cp, "Public and private key generation for PuTTY",
- IDC_TITLE);
beginbox(&cp, "Key", IDC_BOX_KEY);
cp2 = cp;
statictext(&cp2, "No key.", 1, IDC_NOKEY);
EnableWindow(hwnd, 1);
SetActiveWindow(hwnd);
return 0;
+ case IDC_GIVEHELP:
+ if (HIWORD(wParam) == BN_CLICKED ||
+ HIWORD(wParam) == BN_DOUBLECLICKED) {
+ if (help_path) {
+ WinHelp(hwnd, help_path, HELP_COMMAND,
+ (DWORD)"JI(`',`puttygen.general')");
+ requested_help = TRUE;
+ }
+ }
+ return 0;
case IDC_GENERATE:
state =
(struct MainDlgState *) GetWindowLong(hwnd, GWL_USERDATA);
if (prompt_keyfile(hwnd, "Load private key:", filename, 0)) {
char passphrase[PASSPHRASE_MAXLEN];
int needs_pass;
- int type;
+ int type, realtype;
int ret;
char *comment;
struct PassphraseProcStruct pps;
struct RSAKey newkey1;
struct ssh2_userkey *newkey2 = NULL;
- type = key_type(filename);
- if (type != SSH_KEYTYPE_SSH1 && type != SSH_KEYTYPE_SSH2) {
+ type = realtype = key_type(filename);
+ if (type != SSH_KEYTYPE_SSH1 &&
+ type != SSH_KEYTYPE_SSH2 &&
+ !import_possible(type)) {
char msg[256];
sprintf(msg, "Couldn't load private key (%s)",
key_type_to_str(type));
break;
}
+ if (type != SSH_KEYTYPE_SSH1 &&
+ type != SSH_KEYTYPE_SSH2) {
+ realtype = type;
+ type = import_target_type(type);
+ }
+
comment = NULL;
- if (type == SSH_KEYTYPE_SSH1)
+ if (realtype == SSH_KEYTYPE_SSH1)
needs_pass = rsakey_encrypted(filename, &comment);
- else
+ else if (realtype == SSH_KEYTYPE_SSH2)
needs_pass =
ssh2_userkey_encrypted(filename, &comment);
+ else
+ needs_pass = import_encrypted(filename, realtype,
+ &comment);
pps.passphrase = passphrase;
pps.comment = comment;
do {
}
} else
*passphrase = '\0';
- if (type == SSH_KEYTYPE_SSH1)
- ret =
- loadrsakey(filename, &newkey1, passphrase);
- else {
- newkey2 =
- ssh2_load_userkey(filename, passphrase);
+ if (type == SSH_KEYTYPE_SSH1) {
+ if (realtype == type)
+ ret = loadrsakey(filename, &newkey1,
+ passphrase);
+ else
+ ret = import_ssh1(filename, realtype,
+ &newkey1, passphrase);
+ } else {
+ if (realtype == type)
+ newkey2 = ssh2_load_userkey(filename,
+ passphrase);
+ else
+ newkey2 = import_ssh2(filename, realtype,
+ passphrase);
if (newkey2 == SSH2_WRONG_PASSPHRASE)
ret = -1;
else if (!newkey2)
projects / u / mdw / putty / commitdiff