return 0;
}
+/*
+ * Strip trailing CRs and LFs at the end of a line of text.
+ */
+void strip_crlf(char *str)
+{
+ char *p = str + strlen(str);
+
+ while (p > str && (p[-1] == '\r' || p[-1] == '\n'))
+ *--p = '\0';
+}
+
/* ----------------------------------------------------------------------
* Helper routines. (The base64 ones are defined in sshpubk.c.)
*/
if (len < 4)
goto error;
- bytes = GET_32BIT(d);
- if (len < 4+bytes)
+ bytes = toint(GET_32BIT(d));
+ if (bytes < 0 || len-4 < bytes)
goto error;
ret->start = d + 4;
*/
enum { OSSH_DSA, OSSH_RSA };
+enum { OSSH_ENC_3DES, OSSH_ENC_AES };
struct openssh_key {
int type;
- int encrypted;
+ int encrypted, encryption;
char iv[32];
unsigned char *keyblob;
int keyblob_len, keyblob_size;
const char **errmsg_p)
{
struct openssh_key *ret;
- FILE *fp;
- char buffer[256];
+ FILE *fp = NULL;
+ char *line = NULL;
char *errmsg, *p;
int headers_done;
char base64_bit[4];
ret->encrypted = 0;
memset(ret->iv, 0, sizeof(ret->iv));
- fp = f_open(*filename, "r");
+ fp = f_open(filename, "r", FALSE);
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")) {
+
+ if (!(line = fgetline(fp))) {
+ errmsg = "unexpected end of file";
+ goto error;
+ }
+ strip_crlf(line);
+ if (0 != strncmp(line, "-----BEGIN ", 11) ||
+ 0 != strcmp(line+strlen(line)-16, "PRIVATE KEY-----")) {
errmsg = "file does not begin with OpenSSH key header";
goto error;
}
- if (!strcmp(buffer, "-----BEGIN RSA PRIVATE KEY-----\n"))
+ if (!strcmp(line, "-----BEGIN RSA PRIVATE KEY-----"))
ret->type = OSSH_RSA;
- else if (!strcmp(buffer, "-----BEGIN DSA PRIVATE KEY-----\n"))
+ else if (!strcmp(line, "-----BEGIN DSA PRIVATE KEY-----"))
ret->type = OSSH_DSA;
else {
errmsg = "unrecognised key type";
goto error;
}
+ smemclr(line, strlen(line));
+ sfree(line);
+ line = NULL;
headers_done = 0;
while (1) {
- if (!fgets(buffer, sizeof(buffer), fp)) {
+ if (!(line = fgetline(fp))) {
errmsg = "unexpected end of file";
goto error;
}
- if (0 == strncmp(buffer, "-----END ", 9) &&
- 0 == strcmp(buffer+strlen(buffer)-17, "PRIVATE KEY-----\n"))
+ strip_crlf(line);
+ if (0 == strncmp(line, "-----END ", 9) &&
+ 0 == strcmp(line+strlen(line)-16, "PRIVATE KEY-----")) {
+ sfree(line);
+ line = NULL;
break; /* done */
- if ((p = strchr(buffer, ':')) != NULL) {
+ }
+ if ((p = strchr(line, ':')) != 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 (!strcmp(line, "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"))
+ if (!strcmp(p, "ENCRYPTED"))
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";
+ } else if (!strcmp(line, "DEK-Info")) {
+ int i, j, ivlen;
+
+ if (!strncmp(p, "DES-EDE3-CBC,", 13)) {
+ ret->encryption = OSSH_ENC_3DES;
+ ivlen = 8;
+ } else if (!strncmp(p, "AES-128-CBC,", 12)) {
+ ret->encryption = OSSH_ENC_AES;
+ ivlen = 16;
+ } else {
+ errmsg = "unsupported cipher";
goto error;
}
- p += 13;
- for (i = 0; i < 8; i++) {
- if (1 != sscanf(p, "%2x", &j))
- break;
+ p = strchr(p, ',') + 1;/* always non-NULL, by above checks */
+ for (i = 0; i < ivlen; i++) {
+ if (1 != sscanf(p, "%2x", &j)) {
+ errmsg = "expected more iv data in DEK-Info";
+ goto error;
+ }
ret->iv[i] = j;
p += 2;
}
- if (i < 8) {
- errmsg = "expected 16-digit iv in DEK-Info";
+ if (*p) {
+ errmsg = "more iv data than expected in DEK-Info";
goto error;
}
}
} else {
headers_done = 1;
- p = buffer;
+ p = line;
while (isbase64(*p)) {
base64_bit[base64_chars++] = *p;
if (base64_chars == 4) {
memcpy(ret->keyblob + ret->keyblob_len, out, len);
ret->keyblob_len += len;
- memset(out, 0, sizeof(out));
+ smemclr(out, sizeof(out));
}
p++;
}
}
+ smemclr(line, strlen(line));
+ sfree(line);
+ line = NULL;
}
+ fclose(fp);
+ fp = NULL;
+
if (ret->keyblob_len == 0 || !ret->keyblob) {
errmsg = "key body not present";
goto error;
goto error;
}
- memset(buffer, 0, sizeof(buffer));
- memset(base64_bit, 0, sizeof(base64_bit));
+ smemclr(base64_bit, sizeof(base64_bit));
if (errmsg_p) *errmsg_p = NULL;
return ret;
error:
- memset(buffer, 0, sizeof(buffer));
- memset(base64_bit, 0, sizeof(base64_bit));
+ if (line) {
+ smemclr(line, strlen(line));
+ sfree(line);
+ line = NULL;
+ }
+ smemclr(base64_bit, sizeof(base64_bit));
if (ret) {
if (ret->keyblob) {
- memset(ret->keyblob, 0, ret->keyblob_size);
+ smemclr(ret->keyblob, ret->keyblob_size);
sfree(ret->keyblob);
}
- memset(&ret, 0, sizeof(ret));
+ smemclr(ret, sizeof(*ret));
sfree(ret);
}
if (errmsg_p) *errmsg_p = errmsg;
+ if (fp) fclose(fp);
return NULL;
}
if (!key)
return 0;
ret = key->encrypted;
- memset(key->keyblob, 0, key->keyblob_size);
+ smemclr(key->keyblob, key->keyblob_size);
sfree(key->keyblob);
- memset(&key, 0, sizeof(key));
+ smemclr(key, sizeof(*key));
sfree(key);
return ret;
}
* - 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
+ *
+ * (Note that only 8 bytes of the iv are used for key
+ * derivation, even when the key is encrypted with AES and
+ * hence there are 16 bytes available.)
*/
struct MD5Context md5c;
unsigned char keybuf[32];
/*
* Now decrypt the key blob.
*/
- des3_decrypt_pubkey_ossh(keybuf, (unsigned char *)key->iv,
- key->keyblob, key->keyblob_len);
+ if (key->encryption == OSSH_ENC_3DES)
+ des3_decrypt_pubkey_ossh(keybuf, (unsigned char *)key->iv,
+ key->keyblob, key->keyblob_len);
+ else {
+ void *ctx;
+ assert(key->encryption == OSSH_ENC_AES);
+ ctx = aes_make_context();
+ aes128_key(ctx, keybuf);
+ aes_iv(ctx, (unsigned char *)key->iv);
+ aes_ssh2_decrypt_blk(ctx, key->keyblob, key->keyblob_len);
+ aes_free_context(ctx);
+ }
- memset(&md5c, 0, sizeof(md5c));
- memset(keybuf, 0, sizeof(keybuf));
+ smemclr(&md5c, sizeof(md5c));
+ smemclr(keybuf, sizeof(keybuf));
}
/*
p = key->keyblob;
- /* Expect the SEQUENCE header. Take its absence as a failure to decrypt. */
+ /* Expect the SEQUENCE header. Take its absence as a failure to
+ * decrypt, if the key was encrypted. */
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;
+ retval = key->encrypted ? SSH2_WRONG_PASSPHRASE : NULL;
goto error;
}
if (ret < 0 || id != 2 ||
key->keyblob+key->keyblob_len-p < len) {
errmsg = "ASN.1 decoding failure";
- retval = SSH2_WRONG_PASSPHRASE;
+ retval = key->encrypted ? SSH2_WRONG_PASSPHRASE : NULL;
goto error;
}
error:
if (blob) {
- memset(blob, 0, blobsize);
+ smemclr(blob, blobsize);
sfree(blob);
}
- memset(key->keyblob, 0, key->keyblob_size);
+ smemclr(key->keyblob, key->keyblob_size);
sfree(key->keyblob);
- memset(&key, 0, sizeof(key));
+ smemclr(key, sizeof(*key));
sfree(key);
if (errmsg_p) *errmsg_p = errmsg;
return retval;
struct mpint_pos n, e, d, p, q, iqmp, dmp1, dmq1;
Bignum bd, bp, bq, bdmp1, bdmq1;
+ /*
+ * These blobs were generated from inside PuTTY, so we needn't
+ * treat them as untrusted.
+ */
pos = 4 + GET_32BIT(pubblob);
pos += ssh2_read_mpint(pubblob+pos, publen-pos, &e);
pos += ssh2_read_mpint(pubblob+pos, publen-pos, &n);
int pos;
struct mpint_pos p, q, g, y, x;
+ /*
+ * These blobs were generated from inside PuTTY, so we needn't
+ * treat them as untrusted.
+ */
pos = 4 + GET_32BIT(pubblob);
pos += ssh2_read_mpint(pubblob+pos, publen-pos, &p);
pos += ssh2_read_mpint(pubblob+pos, publen-pos, &q);
footer = "-----END DSA PRIVATE KEY-----\n";
} else {
assert(0); /* zoinks! */
+ exit(1); /* XXX: GCC doesn't understand assert() on some systems. */
}
/*
/*
* Encrypt the key.
+ *
+ * For the moment, we still encrypt our OpenSSH keys using
+ * old-style 3DES.
*/
if (passphrase) {
/*
*/
des3_encrypt_pubkey_ossh(keybuf, iv, outblob, outlen);
- memset(&md5c, 0, sizeof(md5c));
- memset(keybuf, 0, sizeof(keybuf));
+ smemclr(&md5c, sizeof(md5c));
+ smemclr(keybuf, sizeof(keybuf));
}
/*
* And save it. We'll use Unix line endings just in case it's
* subsequently transferred in binary mode.
*/
- fp = f_open(*filename, "wb"); /* ensure Unix line endings */
+ fp = f_open(filename, "wb", TRUE); /* ensure Unix line endings */
if (!fp)
goto error;
fputs(header, fp);
error:
if (outblob) {
- memset(outblob, 0, outlen);
+ smemclr(outblob, outlen);
sfree(outblob);
}
if (spareblob) {
- memset(spareblob, 0, sparelen);
+ smemclr(spareblob, sparelen);
sfree(spareblob);
}
if (privblob) {
- memset(privblob, 0, privlen);
+ smemclr(privblob, privlen);
sfree(privblob);
}
if (pubblob) {
- memset(pubblob, 0, publen);
+ smemclr(pubblob, publen);
sfree(pubblob);
}
return ret;
{
struct sshcom_key *ret;
FILE *fp;
- char buffer[256];
- int len;
+ char *line = NULL;
+ int hdrstart, len;
char *errmsg, *p;
int headers_done;
char base64_bit[4];
ret->keyblob = NULL;
ret->keyblob_len = ret->keyblob_size = 0;
- fp = f_open(*filename, "r");
+ fp = f_open(filename, "r", FALSE);
if (!fp) {
errmsg = "unable to open key file";
goto error;
}
- if (!fgets(buffer, sizeof(buffer), fp) ||
- 0 != strcmp(buffer, "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----\n")) {
+ if (!(line = fgetline(fp))) {
+ errmsg = "unexpected end of file";
+ goto error;
+ }
+ strip_crlf(line);
+ if (0 != strcmp(line, "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----")) {
errmsg = "file does not begin with ssh.com key header";
goto error;
}
+ smemclr(line, strlen(line));
+ sfree(line);
+ line = NULL;
headers_done = 0;
while (1) {
- if (!fgets(buffer, sizeof(buffer), fp)) {
+ if (!(line = fgetline(fp))) {
errmsg = "unexpected end of file";
goto error;
}
- if (!strcmp(buffer, "---- END SSH2 ENCRYPTED PRIVATE KEY ----\n"))
+ strip_crlf(line);
+ if (!strcmp(line, "---- END SSH2 ENCRYPTED PRIVATE KEY ----")) {
+ sfree(line);
+ line = NULL;
break; /* done */
- if ((p = strchr(buffer, ':')) != NULL) {
+ }
+ if ((p = strchr(line, ':')) != NULL) {
if (headers_done) {
errmsg = "header found in body of key data";
goto error;
}
*p++ = '\0';
while (*p && isspace((unsigned char)*p)) p++;
+ hdrstart = p - line;
+
/*
* Header lines can end in a trailing backslash for
* continuation.
*/
- while ((len = strlen(p)) > (int)(sizeof(buffer) - (p-buffer) -1) ||
- p[len-1] != '\n' || p[len-2] == '\\') {
- if (len > (int)((p-buffer) + sizeof(buffer)-2)) {
- errmsg = "header line too long to deal with";
- goto error;
- }
- if (!fgets(p+len-2, sizeof(buffer)-(p-buffer)-(len-2), fp)) {
+ len = hdrstart + strlen(line+hdrstart);
+ assert(!line[len]);
+ while (line[len-1] == '\\') {
+ char *line2;
+ int line2len;
+
+ line2 = fgetline(fp);
+ if (!line2) {
errmsg = "unexpected end of file";
goto error;
}
+ strip_crlf(line2);
+
+ line2len = strlen(line2);
+ line = sresize(line, len + line2len + 1, char);
+ strcpy(line + len - 1, line2);
+ len += line2len - 1;
+ assert(!line[len]);
+
+ smemclr(line2, strlen(line2));
+ sfree(line2);
+ line2 = NULL;
}
- p[strcspn(p, "\n")] = '\0';
- if (!strcmp(buffer, "Comment")) {
+ p = line + hdrstart;
+ strip_crlf(p);
+ if (!strcmp(line, "Comment")) {
/* Strip quotes in comment if present. */
if (p[0] == '"' && p[strlen(p)-1] == '"') {
p++;
} else {
headers_done = 1;
- p = buffer;
+ p = line;
while (isbase64(*p)) {
base64_bit[base64_chars++] = *p;
if (base64_chars == 4) {
p++;
}
}
+ smemclr(line, strlen(line));
+ sfree(line);
+ line = NULL;
}
if (ret->keyblob_len == 0 || !ret->keyblob) {
goto error;
}
+ fclose(fp);
if (errmsg_p) *errmsg_p = NULL;
return ret;
error:
+ if (fp)
+ fclose(fp);
+
+ if (line) {
+ smemclr(line, strlen(line));
+ sfree(line);
+ line = NULL;
+ }
if (ret) {
if (ret->keyblob) {
- memset(ret->keyblob, 0, ret->keyblob_size);
+ smemclr(ret->keyblob, ret->keyblob_size);
sfree(ret->keyblob);
}
- memset(&ret, 0, sizeof(ret));
+ smemclr(ret, sizeof(*ret));
sfree(ret);
}
if (errmsg_p) *errmsg_p = errmsg;
struct sshcom_key *key = load_sshcom_key(filename, NULL);
int pos, len, answer;
+ answer = 0;
+
*comment = NULL;
if (!key)
- return 0;
+ goto done;
/*
* Check magic number.
*/
- if (GET_32BIT(key->keyblob) != 0x3f6ff9eb)
- return 0; /* key is invalid */
+ if (GET_32BIT(key->keyblob) != 0x3f6ff9eb) {
+ goto done; /* key is invalid */
+ }
/*
* Find the cipher-type string.
*/
- answer = 0;
pos = 8;
if (key->keyblob_len < pos+4)
goto done; /* key is far too short */
- pos += 4 + GET_32BIT(key->keyblob + pos); /* skip key type */
- if (key->keyblob_len < pos+4)
+ len = toint(GET_32BIT(key->keyblob + pos));
+ if (len < 0 || len > key->keyblob_len - pos - 4)
goto done; /* key is far too short */
- len = GET_32BIT(key->keyblob + pos); /* find cipher-type length */
- if (key->keyblob_len < pos+4+len)
+ pos += 4 + len; /* skip key type */
+ len = toint(GET_32BIT(key->keyblob + pos)); /* find cipher-type length */
+ if (len < 0 || len > key->keyblob_len - pos - 4)
goto done; /* cipher type string is incomplete */
if (len != 4 || 0 != memcmp(key->keyblob + pos + 4, "none", 4))
answer = 1;
done:
- *comment = dupstr(key->comment);
- memset(key->keyblob, 0, key->keyblob_size);
- sfree(key->keyblob);
- memset(&key, 0, sizeof(key));
- sfree(key);
+ if (key) {
+ *comment = dupstr(key->comment);
+ smemclr(key->keyblob, key->keyblob_size);
+ sfree(key->keyblob);
+ smemclr(key, sizeof(*key));
+ sfree(key);
+ } else {
+ *comment = dupstr("");
+ }
return answer;
}
static int sshcom_read_mpint(void *data, int len, struct mpint_pos *ret)
{
- int bits;
- int bytes;
+ unsigned bits, bytes;
unsigned char *d = (unsigned char *) data;
if (len < 4)
*/
pos = 8;
if (key->keyblob_len < pos+4 ||
- (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) {
+ (len = toint(GET_32BIT(key->keyblob + pos))) < 0 ||
+ len > key->keyblob_len - pos - 4) {
errmsg = "key blob does not contain a key type string";
goto error;
}
* Determine the cipher type.
*/
if (key->keyblob_len < pos+4 ||
- (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) {
+ (len = toint(GET_32BIT(key->keyblob + pos))) < 0 ||
+ len > key->keyblob_len - pos - 4) {
errmsg = "key blob does not contain a cipher type string";
goto error;
}
* Get hold of the encrypted part of the key.
*/
if (key->keyblob_len < pos+4 ||
- (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) {
+ (len = toint(GET_32BIT(key->keyblob + pos))) < 0 ||
+ len > key->keyblob_len - pos - 4) {
errmsg = "key blob does not contain actual key data";
goto error;
}
des3_decrypt_pubkey_ossh(keybuf, iv, (unsigned char *)ciphertext,
cipherlen);
- memset(&md5c, 0, sizeof(md5c));
- memset(keybuf, 0, sizeof(keybuf));
+ smemclr(&md5c, sizeof(md5c));
+ smemclr(keybuf, sizeof(keybuf));
/*
* Hereafter we return WRONG_PASSPHRASE for any parsing
/*
* Strip away the containing string to get to the real meat.
*/
- len = GET_32BIT(ciphertext);
+ len = toint(GET_32BIT(ciphertext));
if (len < 0 || len > cipherlen-4) {
errmsg = "containing string was ill-formed";
goto error;
pos += put_mp(blob+pos, p.start, p.bytes);
pos += put_mp(blob+pos, u.start, u.bytes);
privlen = pos - publen;
- } else if (type == DSA) {
+ } else {
struct mpint_pos p, q, g, x, y;
int pos = 4;
+
+ assert(type == DSA); /* the only other option from the if above */
+
if (GET_32BIT(ciphertext) != 0) {
errmsg = "predefined DSA parameters not supported";
goto error;
publen = pos;
pos += put_mp(blob+pos, x.start, x.bytes);
privlen = pos - publen;
- } else
- return NULL;
+ }
assert(privlen > 0); /* should have bombed by now if not */
error:
if (blob) {
- memset(blob, 0, blobsize);
+ smemclr(blob, blobsize);
sfree(blob);
}
- memset(key->keyblob, 0, key->keyblob_size);
+ smemclr(key->keyblob, key->keyblob_size);
sfree(key->keyblob);
- memset(&key, 0, sizeof(key));
+ smemclr(key, sizeof(*key));
sfree(key);
if (errmsg_p) *errmsg_p = errmsg;
return ret;
int pos;
struct mpint_pos n, e, d, p, q, iqmp;
+ /*
+ * These blobs were generated from inside PuTTY, so we needn't
+ * treat them as untrusted.
+ */
pos = 4 + GET_32BIT(pubblob);
pos += ssh2_read_mpint(pubblob+pos, publen-pos, &e);
pos += ssh2_read_mpint(pubblob+pos, publen-pos, &n);
int pos;
struct mpint_pos p, q, g, y, x;
+ /*
+ * These blobs were generated from inside PuTTY, so we needn't
+ * treat them as untrusted.
+ */
pos = 4 + GET_32BIT(pubblob);
pos += ssh2_read_mpint(pubblob+pos, publen-pos, &p);
pos += ssh2_read_mpint(pubblob+pos, publen-pos, &q);
type = "dl-modp{sign{dsa-nist-sha1},dh{plain}}";
} else {
assert(0); /* zoinks! */
+ exit(1); /* XXX: GCC doesn't understand assert() on some systems. */
}
/*
des3_encrypt_pubkey_ossh(keybuf, iv, (unsigned char *)ciphertext,
cipherlen);
- memset(&md5c, 0, sizeof(md5c));
- memset(keybuf, 0, sizeof(keybuf));
+ smemclr(&md5c, sizeof(md5c));
+ smemclr(keybuf, sizeof(keybuf));
}
/*
* And save it. We'll use Unix line endings just in case it's
* subsequently transferred in binary mode.
*/
- fp = f_open(*filename, "wb"); /* ensure Unix line endings */
+ fp = f_open(filename, "wb", TRUE); /* ensure Unix line endings */
if (!fp)
goto error;
fputs("---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----\n", fp);
error:
if (outblob) {
- memset(outblob, 0, outlen);
+ smemclr(outblob, outlen);
sfree(outblob);
}
if (privblob) {
- memset(privblob, 0, privlen);
+ smemclr(privblob, privlen);
sfree(privblob);
}
if (pubblob) {
- memset(pubblob, 0, publen);
+ smemclr(pubblob, publen);
sfree(pubblob);
}
return ret;
projects / u / mdw / putty / blobdiff