#include "ssh.h"
#include "misc.h"
-#define PUT_32BIT(cp, value) do { \
- (cp)[3] = (unsigned char)(value); \
- (cp)[2] = (unsigned char)((value) >> 8); \
- (cp)[1] = (unsigned char)((value) >> 16); \
- (cp)[0] = (unsigned char)((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(const Filename *filename);
-struct ssh2_userkey *openssh_read(const Filename *filename, char *passphrase);
+struct ssh2_userkey *openssh_read(const Filename *filename, char *passphrase,
+ const char **errmsg_p);
int openssh_write(const Filename *filename, struct ssh2_userkey *key,
char *passphrase);
int sshcom_encrypted(const Filename *filename, char **comment);
-struct ssh2_userkey *sshcom_read(const Filename *filename, char *passphrase);
+struct ssh2_userkey *sshcom_read(const Filename *filename, char *passphrase,
+ const char **errmsg_p);
int sshcom_write(const Filename *filename, struct ssh2_userkey *key,
char *passphrase);
int import_target_type(int type)
{
/*
- * There are no known foreign SSH1 key formats.
+ * There are no known foreign SSH-1 key formats.
*/
return SSH_KEYTYPE_SSH2;
}
{
if (type == SSH_KEYTYPE_OPENSSH) {
/* OpenSSH doesn't do key comments */
- *comment = dupstr(filename_to_str(*filename));
+ *comment = dupstr(filename_to_str(filename));
return openssh_encrypted(filename);
}
if (type == SSH_KEYTYPE_SSHCOM) {
}
/*
- * Import an SSH1 key.
+ * Import an SSH-1 key.
*/
int import_ssh1(const Filename *filename, int type,
- struct RSAKey *key, char *passphrase)
+ struct RSAKey *key, char *passphrase, const char **errmsg_p)
{
return 0;
}
/*
- * Import an SSH2 key.
+ * Import an SSH-2 key.
*/
struct ssh2_userkey *import_ssh2(const Filename *filename, int type,
- char *passphrase)
+ char *passphrase, const char **errmsg_p)
{
if (type == SSH_KEYTYPE_OPENSSH)
- return openssh_read(filename, passphrase);
+ return openssh_read(filename, passphrase, errmsg_p);
if (type == SSH_KEYTYPE_SSHCOM)
- return sshcom_read(filename, passphrase);
+ return sshcom_read(filename, passphrase, errmsg_p);
return NULL;
}
/*
- * Export an SSH1 key.
+ * Export an SSH-1 key.
*/
int export_ssh1(const Filename *filename, int type, struct RSAKey *key,
char *passphrase)
}
/*
- * Export an SSH2 key.
+ * Export an SSH-2 key.
*/
int export_ssh2(const Filename *filename, int type,
struct ssh2_userkey *key, char *passphrase)
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.)
*/
/* Primitive versus constructed bit. */
#define ASN1_CONSTRUCTED (1 << 5)
-int ber_read_id_len(void *source, int sourcelen,
- int *id, int *length, int *flags)
+static int ber_read_id_len(void *source, int sourcelen,
+ int *id, int *length, int *flags)
{
unsigned char *p = (unsigned char *) source;
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);
}
- *id = (*id << 7) | (*p & 0x7F);
p++, sourcelen--;
} else {
*id = *p & 0x1F;
* Will avoid writing anything if dest is NULL, but still return
* amount of space required.
*/
-int ber_write_id_len(void *dest, int id, int length, int flags)
+static int ber_write_id_len(void *dest, int id, int length, int flags)
{
unsigned char *d = (unsigned char *)dest;
int len = 0;
/* Simple structure to point to an mp-int within a blob. */
struct mpint_pos { void *start; int bytes; };
-int ssh2_read_mpint(void *data, int len, struct mpint_pos *ret)
+static int ssh2_read_mpint(void *data, int len, struct mpint_pos *ret)
{
int bytes;
unsigned char *d = (unsigned char *) data;
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;
};
-struct openssh_key *load_openssh_key(const Filename *filename)
+static struct openssh_key *load_openssh_key(const Filename *filename,
+ 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];
int base64_chars = 0;
- ret = smalloc(sizeof(*ret));
+ ret = snew(struct openssh_key);
ret->keyblob = NULL;
ret->keyblob_len = ret->keyblob_size = 0;
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";
+ 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";
+
+ if (!(line = fgetline(fp))) {
+ errmsg = "unexpected end of file";
goto error;
}
- if (!strcmp(buffer, "-----BEGIN RSA PRIVATE KEY-----\n"))
+ 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(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";
+ 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)) {
- errmsg = "Unexpected end of file";
+ 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";
+ 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) {
len = base64_decode_atom(base64_bit, out);
if (len <= 0) {
- errmsg = "Invalid base64 encoding";
+ 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);
+ ret->keyblob = sresize(ret->keyblob, ret->keyblob_size,
+ unsigned char);
}
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";
+ 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";
+ errmsg = "encrypted key blob is not a multiple of cipher block size";
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;
}
int openssh_encrypted(const Filename *filename)
{
- struct openssh_key *key = load_openssh_key(filename);
+ struct openssh_key *key = load_openssh_key(filename, NULL);
int ret;
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;
}
-struct ssh2_userkey *openssh_read(const Filename *filename, char *passphrase)
+struct ssh2_userkey *openssh_read(const Filename *filename, char *passphrase,
+ const char **errmsg_p)
{
- struct openssh_key *key = load_openssh_key(filename);
+ struct openssh_key *key = load_openssh_key(filename, errmsg_p);
struct ssh2_userkey *retkey;
unsigned char *p;
int ret, id, len, flags;
struct ssh2_userkey *retval = NULL;
char *errmsg;
unsigned char *blob;
- int blobsize, blobptr, privptr;
- char *modptr;
- int modlen;
+ int blobsize = 0, blobptr, privptr;
+ char *modptr = NULL;
+ int modlen = 0;
blob = NULL;
* - 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];
MD5Init(&md5c);
- MD5Update(&md5c, passphrase, strlen(passphrase));
- MD5Update(&md5c, key->iv, 8);
+ MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase));
+ MD5Update(&md5c, (unsigned char *)key->iv, 8);
MD5Final(keybuf, &md5c);
MD5Init(&md5c);
MD5Update(&md5c, keybuf, 16);
- MD5Update(&md5c, passphrase, strlen(passphrase));
- MD5Update(&md5c, key->iv, 8);
+ MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase));
+ MD5Update(&md5c, (unsigned char *)key->iv, 8);
MD5Final(keybuf+16, &md5c);
/*
* Now decrypt the key blob.
*/
- des3_decrypt_pubkey_ossh(keybuf, 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;
}
num_integers = 9;
else if (key->type == OSSH_DSA)
num_integers = 6;
+ else
+ num_integers = 0; /* placate compiler warnings */
/*
* Space to create key blob in.
*/
blobsize = 256+key->keyblob_len;
- blob = smalloc(blobsize);
+ blob = snewn(blobsize, unsigned char);
PUT_32BIT(blob, 7);
if (key->type == OSSH_DSA)
memcpy(blob+4, "ssh-dss", 7);
if (ret < 0 || id != 2 ||
key->keyblob+key->keyblob_len-p < len) {
errmsg = "ASN.1 decoding failure";
+ retval = key->encrypted ? SSH2_WRONG_PASSPHRASE : NULL;
goto error;
}
* this is some sort of version indication).
*/
if (len != 1 || p[0] != 0) {
- errmsg = "Version number mismatch";
+ errmsg = "version number mismatch";
goto error;
}
} else if (key->type == OSSH_RSA) {
*/
if (i == 1) {
/* Save the details for after we deal with number 2. */
- modptr = p;
+ modptr = (char *)p;
modlen = len;
} else if (i != 6 && i != 7) {
PUT_32BIT(blob+blobptr, len);
* the sanity checks for free.
*/
assert(privptr > 0); /* should have bombed by now if not */
- retkey = smalloc(sizeof(struct ssh2_userkey));
+ retkey = snew(struct ssh2_userkey);
retkey->alg = (key->type == OSSH_RSA ? &ssh_rsa : &ssh_dss);
retkey->data = retkey->alg->createkey(blob, privptr,
blob+privptr, blobptr-privptr);
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;
}
char *passphrase)
{
unsigned char *pubblob, *privblob, *spareblob;
- int publen, privlen, sparelen;
+ int publen, privlen, sparelen = 0;
unsigned char *outblob;
int outlen;
struct mpint_pos numbers[9];
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);
dmp1.bytes = (bignum_bitcount(bdmp1)+8)/8;
dmq1.bytes = (bignum_bitcount(bdmq1)+8)/8;
sparelen = dmp1.bytes + dmq1.bytes;
- spareblob = smalloc(sparelen);
+ spareblob = snewn(sparelen, unsigned char);
dmp1.start = spareblob;
dmq1.start = spareblob + dmp1.bytes;
for (i = 0; i < dmp1.bytes; i++)
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. */
}
/*
/*
* Now we know how big outblob needs to be. Allocate it.
*/
- outblob = smalloc(outlen);
+ outblob = snewn(outlen, unsigned char);
/*
* And write the data into it.
/*
* Encrypt the key.
+ *
+ * For the moment, we still encrypt our OpenSSH keys using
+ * old-style 3DES.
*/
if (passphrase) {
/*
for (i = 0; i < 8; i++) iv[i] = random_byte();
MD5Init(&md5c);
- MD5Update(&md5c, passphrase, strlen(passphrase));
+ MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase));
MD5Update(&md5c, iv, 8);
MD5Final(keybuf, &md5c);
MD5Init(&md5c);
MD5Update(&md5c, keybuf, 16);
- MD5Update(&md5c, passphrase, strlen(passphrase));
+ MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase));
MD5Update(&md5c, iv, 8);
MD5Final(keybuf+16, &md5c);
*/
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;
*/
/*
- * The format of the base64 blob is largely ssh2-packet-formatted,
+ * The format of the base64 blob is largely SSH-2-packet-formatted,
* except that mpints are a bit different: they're more like the
- * old ssh1 mpint. You have a 32-bit bit count N, followed by
+ * old SSH-1 mpint. You have a 32-bit bit count N, followed by
* (N+7)/8 bytes of data.
*
* So. The blob contains:
* - string encrypted-blob
*
* (The first size field includes the size field itself and the
- * magic number before it. All other size fields are ordinary ssh2
+ * magic number before it. All other size fields are ordinary SSH-2
* strings, so the size field indicates how much data is to
* _follow_.)
*
* `dl-modp{sign{dsa' prefixes.
*
* Finally, the encryption. The cipher-type string appears to be
- * either `none' or `3des-cbc'. Looks as if this is SSH2-style
+ * either `none' or `3des-cbc'. Looks as if this is SSH-2-style
* 3des-cbc (i.e. outer cbc rather than inner). The key is created
* from the passphrase by means of yet another hashing faff:
*
int keyblob_len, keyblob_size;
};
-struct sshcom_key *load_sshcom_key(const Filename *filename)
+static struct sshcom_key *load_sshcom_key(const Filename *filename,
+ const char **errmsg_p)
{
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];
int base64_chars = 0;
- ret = smalloc(sizeof(*ret));
+ ret = snew(struct sshcom_key);
ret->comment[0] = '\0';
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";
+ errmsg = "unable to open key file";
+ goto error;
+ }
+ if (!(line = fgetline(fp))) {
+ errmsg = "unexpected end of file";
goto error;
}
- if (!fgets(buffer, sizeof(buffer), fp) ||
- 0 != strcmp(buffer, "---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----\n")) {
- errmsg = "File does not begin with ssh.com key header";
+ 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)) {
- errmsg = "Unexpected end of file";
+ 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";
+ 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)) {
- errmsg = "Unexpected end of file";
+ 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) {
len = base64_decode_atom(base64_bit, out);
if (len <= 0) {
- errmsg = "Invalid base64 encoding";
+ 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);
+ ret->keyblob = sresize(ret->keyblob, ret->keyblob_size,
+ unsigned char);
}
memcpy(ret->keyblob + ret->keyblob_len, out, len);
p++;
}
}
+ smemclr(line, strlen(line));
+ sfree(line);
+ line = NULL;
}
if (ret->keyblob_len == 0 || !ret->keyblob) {
- errmsg = "Key body not present";
+ errmsg = "key body not present";
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;
return NULL;
}
int sshcom_encrypted(const Filename *filename, char **comment)
{
- struct sshcom_key *key = load_sshcom_key(filename);
+ 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;
}
-int sshcom_read_mpint(void *data, int len, struct mpint_pos *ret)
+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)
return len+4;
}
-struct ssh2_userkey *sshcom_read(const Filename *filename, char *passphrase)
+struct ssh2_userkey *sshcom_read(const Filename *filename, char *passphrase,
+ const char **errmsg_p)
{
- struct sshcom_key *key = load_sshcom_key(filename);
+ struct sshcom_key *key = load_sshcom_key(filename, errmsg_p);
char *errmsg;
int pos, len;
const char prefix_rsa[] = "if-modn{sign{rsa";
struct ssh2_userkey *ret = NULL, *retkey;
const struct ssh_signkey *alg;
unsigned char *blob = NULL;
- int blobsize, publen, privlen;
+ int blobsize = 0, publen, privlen;
if (!key)
return NULL;
* Check magic number.
*/
if (GET_32BIT(key->keyblob) != SSHCOM_MAGIC_NUMBER) {
- errmsg = "Key does not begin with magic number";
+ errmsg = "key does not begin with magic number";
goto error;
}
*/
pos = 8;
if (key->keyblob_len < pos+4 ||
- (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) {
- errmsg = "Key blob does not contain a key type string";
+ (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;
}
if (len > sizeof(prefix_rsa) - 1 &&
!memcmp(key->keyblob+pos+4, prefix_dsa, sizeof(prefix_dsa) - 1)) {
type = DSA;
} else {
- errmsg = "Key is of unknown type";
+ errmsg = "key is of unknown type";
goto error;
}
pos += 4+len;
* Determine the cipher type.
*/
if (key->keyblob_len < pos+4 ||
- (len = GET_32BIT(key->keyblob + pos)) > key->keyblob_len - pos - 4) {
- errmsg = "Key blob does not contain a cipher type string";
+ (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;
}
if (len == 4 && !memcmp(key->keyblob+pos+4, "none", 4))
else if (len == 8 && !memcmp(key->keyblob+pos+4, "3des-cbc", 8))
encrypted = 1;
else {
- errmsg = "Key encryption is of unknown type";
+ errmsg = "key encryption is of unknown type";
goto error;
}
pos += 4+len;
* 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) {
- errmsg = "Key blob does not contain actual key data";
+ (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;
}
- ciphertext = key->keyblob + pos + 4;
+ ciphertext = (char *)key->keyblob + pos + 4;
cipherlen = len;
if (cipherlen == 0) {
- errmsg = "Length of key data is zero";
+ errmsg = "length of key data is zero";
goto error;
}
unsigned char keybuf[32], iv[8];
if (cipherlen % 8 != 0) {
- errmsg = "Encrypted part of key is not a multiple of cipher block"
+ errmsg = "encrypted part of key is not a multiple of cipher block"
" size";
goto error;
}
MD5Init(&md5c);
- MD5Update(&md5c, passphrase, strlen(passphrase));
+ MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase));
MD5Final(keybuf, &md5c);
MD5Init(&md5c);
- MD5Update(&md5c, passphrase, strlen(passphrase));
+ MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase));
MD5Update(&md5c, keybuf, 16);
MD5Final(keybuf+16, &md5c);
* Now decrypt the key blob.
*/
memset(iv, 0, sizeof(iv));
- des3_decrypt_pubkey_ossh(keybuf, iv, ciphertext, cipherlen);
+ 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);
- if (len > cipherlen-4) {
+ len = toint(GET_32BIT(ciphertext));
+ if (len < 0 || len > cipherlen-4) {
errmsg = "containing string was ill-formed";
goto error;
}
* end up feeding them to alg->createkey().
*/
blobsize = cipherlen + 256;
- blob = smalloc(blobsize);
+ blob = snewn(blobsize, unsigned char);
privlen = 0;
if (type == RSA) {
struct mpint_pos n, e, d, u, p, q;
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;
assert(privlen > 0); /* should have bombed by now if not */
- retkey = smalloc(sizeof(struct ssh2_userkey));
+ retkey = snew(struct ssh2_userkey);
retkey->alg = alg;
retkey->data = alg->createkey(blob, publen, blob+publen, privlen);
if (!retkey->data) {
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. */
}
/*
outlen = 512;
for (i = 0; i < nnumbers; i++)
outlen += 4 + numbers[i].bytes;
- outblob = smalloc(outlen);
+ outblob = snewn(outlen, unsigned char);
/*
* Create the unencrypted key blob.
while (padding--)
outblob[pos++] = random_byte();
}
- ciphertext = outblob+lenpos+4;
+ ciphertext = (char *)outblob+lenpos+4;
cipherlen = pos - (lenpos+4);
assert(!passphrase || cipherlen % 8 == 0);
/* Wrap up the encrypted blob string. */
unsigned char keybuf[32], iv[8];
MD5Init(&md5c);
- MD5Update(&md5c, passphrase, strlen(passphrase));
+ MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase));
MD5Final(keybuf, &md5c);
MD5Init(&md5c);
- MD5Update(&md5c, passphrase, strlen(passphrase));
+ MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase));
MD5Update(&md5c, keybuf, 16);
MD5Final(keybuf+16, &md5c);
* Now decrypt the key blob.
*/
memset(iv, 0, sizeof(iv));
- des3_encrypt_pubkey_ossh(keybuf, iv, ciphertext, cipherlen);
+ 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