diff options
Diffstat (limited to 'keyimport.c')
-rw-r--r-- | keyimport.c | 158 |
1 files changed, 143 insertions, 15 deletions
diff --git a/keyimport.c b/keyimport.c index 7304e58..ad0c530 100644 --- a/keyimport.c +++ b/keyimport.c @@ -35,6 +35,15 @@ #include "buffer.h" #include "dbutil.h" #include "ecc.h" +#include "ssh.h" + +static const unsigned char OSSH_PKEY_BLOB[] = + "openssh-key-v1\0" /* AUTH_MAGIC */ + "\0\0\0\4none" /* cipher name*/ + "\0\0\0\4none" /* kdf name */ + "\0\0\0\0" /* kdf */ + "\0\0\0\1"; /* key num */ +#define OSSH_PKEY_BLOBLEN (sizeof(OSSH_PKEY_BLOB) - 1) #if DROPBEAR_ECDSA static const unsigned char OID_SEC256R1_BLOB[] = {0x2a, 0x86, 0x48, 0xce, 0x3d, 0x03, 0x01, 0x07}; @@ -352,7 +361,7 @@ struct mpint_pos { void *start; int bytes; }; * Code to read and write OpenSSH private keys. */ -enum { OSSH_DSA, OSSH_RSA, OSSH_EC }; +enum { OSSH_DSA, OSSH_RSA, OSSH_EC, OSSH_PKEY }; struct openssh_key { int type; int encrypted; @@ -364,11 +373,12 @@ struct openssh_key { static struct openssh_key *load_openssh_key(const char *filename) { struct openssh_key *ret; + buffer *buf = NULL; FILE *fp = NULL; char buffer[256]; char *errmsg = NULL, *p = NULL; int headers_done; - unsigned long len, outlen; + unsigned long len; ret = (struct openssh_key*)m_malloc(sizeof(struct openssh_key)); ret->keyblob = NULL; @@ -397,12 +407,15 @@ static struct openssh_key *load_openssh_key(const char *filename) ret->type = OSSH_DSA; else if (!strcmp(buffer, "-----BEGIN EC PRIVATE KEY-----\n")) ret->type = OSSH_EC; + else if (!strcmp(buffer, "-----BEGIN OPENSSH PRIVATE KEY-----\n")) + ret->type = OSSH_PKEY; else { errmsg = "Unrecognised key type"; goto error; } headers_done = 0; + buf = buf_new(0); while (1) { if (!fgets(buffer, sizeof(buffer), fp)) { errmsg = "Unexpected end of file"; @@ -448,20 +461,31 @@ static struct openssh_key *load_openssh_key(const char *filename) } else { headers_done = 1; len = strlen(buffer); - outlen = len*4/3; - if (ret->keyblob_len + outlen > ret->keyblob_size) { - ret->keyblob_size = ret->keyblob_len + outlen + 256; - ret->keyblob = (unsigned char*)m_realloc(ret->keyblob, - ret->keyblob_size); - } - outlen = ret->keyblob_size - ret->keyblob_len; - if (base64_decode((const unsigned char *)buffer, len, - ret->keyblob + ret->keyblob_len, &outlen) != CRYPT_OK){ - errmsg = "Error decoding base64"; - goto error; - } - ret->keyblob_len += outlen; + buf = buf_resize(buf, buf->size + len); + buf_putbytes(buf, buffer, len); + } + } + + if (buf && buf->len) { + ret->keyblob_size = ret->keyblob_len + buf->len*4/3 + 256; + ret->keyblob = (unsigned char*)m_realloc(ret->keyblob, ret->keyblob_size); + len = ret->keyblob_size; + if (base64_decode((const unsigned char *)buf->data, buf->len, + ret->keyblob, &len) != CRYPT_OK){ + errmsg = "Error decoding base64"; + goto error; + } + ret->keyblob_len = len; + } + + if (ret->type == OSSH_PKEY) { + if (ret->keyblob_len < OSSH_PKEY_BLOBLEN || + memcmp(ret->keyblob, OSSH_PKEY_BLOB, OSSH_PKEY_BLOBLEN)) { + errmsg = "Error decoding OpenSSH key"; + goto error; } + ret->keyblob_len -= OSSH_PKEY_BLOBLEN; + memmove(ret->keyblob, ret->keyblob + OSSH_PKEY_BLOBLEN, ret->keyblob_len); } if (ret->keyblob_len == 0 || !ret->keyblob) { @@ -474,10 +498,18 @@ static struct openssh_key *load_openssh_key(const char *filename) goto error; } + if (buf) { + buf_burn(buf); + buf_free(buf); + } m_burn(buffer, sizeof(buffer)); return ret; error: + if (buf) { + buf_burn(buf); + buf_free(buf); + } m_burn(buffer, sizeof(buffer)); if (ret) { if (ret->keyblob) { @@ -570,6 +602,57 @@ static sign_key *openssh_read(const char *filename, const char * UNUSED(passphra } /* + * Now we have a decrypted key blob, which contains OpenSSH + * encoded private key. We must now untangle the OpenSSH format. + */ + if (key->type == OSSH_PKEY) { + blobbuf = buf_new(key->keyblob_len); + buf_putbytes(blobbuf, key->keyblob, key->keyblob_len); + buf_setpos(blobbuf, 0); + + /* limit length of private key blob */ + len = buf_getint(blobbuf); + buf_setlen(blobbuf, blobbuf->pos + len); + + type = DROPBEAR_SIGNKEY_ANY; + if (buf_get_pub_key(blobbuf, retkey, &type) + != DROPBEAR_SUCCESS) { + errmsg = "Error parsing OpenSSH key"; + goto ossh_error; + } + + /* restore full length */ + buf_setlen(blobbuf, key->keyblob_len); + + if (type != DROPBEAR_SIGNKEY_NONE) { + retkey->type = type; + /* limit length of private key blob */ + len = buf_getint(blobbuf); + buf_setlen(blobbuf, blobbuf->pos + len); +#if DROPBEAR_ED25519 + if (type == DROPBEAR_SIGNKEY_ED25519) { + buf_incrpos(blobbuf, 8); + buf_eatstring(blobbuf); + buf_eatstring(blobbuf); + buf_incrpos(blobbuf, -SSH_SIGNKEY_ED25519_LEN-4); + if (buf_get_ed25519_priv_key(blobbuf, retkey->ed25519key) + == DROPBEAR_SUCCESS) { + errmsg = NULL; + retval = retkey; + goto error; + } + } +#endif + } + + errmsg = "Unsupported OpenSSH key type"; + ossh_error: + sign_key_free(retkey); + retkey = NULL; + goto error; + } + + /* * Now we have a decrypted key blob, which contains an ASN.1 * encoded private key. We must now untangle the ASN.1. * @@ -1129,6 +1212,51 @@ static int openssh_write(const char *filename, sign_key *key, } #endif +#if DROPBEAR_ED25519 + if (key->type == DROPBEAR_SIGNKEY_ED25519) { + buffer *buf = buf_new(300); + keyblob = buf_new(100); + extrablob = buf_new(200); + + /* private key blob w/o header */ + buf_put_priv_key(keyblob, key, key->type); + buf_setpos(keyblob, 0); + buf_incrpos(keyblob, buf_getint(keyblob)); + len = buf_getint(keyblob); + + /* header */ + buf_putbytes(buf, OSSH_PKEY_BLOB, OSSH_PKEY_BLOBLEN); + + /* public key */ + buf_put_pub_key(buf, key, key->type); + + /* private key */ + buf_incrwritepos(extrablob, 4); + buf_put_pub_key(extrablob, key, key->type); + buf_putstring(extrablob, buf_getptr(keyblob, len), len); + /* comment */ + buf_putstring(extrablob, "", 0); + /* padding to cipher block length */ + len = (extrablob->len+8) & ~7; + for (i = 1; len - extrablob->len > 0; i++) + buf_putbyte(extrablob, i); + buf_setpos(extrablob, 0); + buf_putbytes(extrablob, "\0\0\0\0\0\0\0\0", 8); + buf_putbufstring(buf, extrablob); + + outlen = len = pos = buf->len; + outblob = (unsigned char*)m_malloc(outlen); + memcpy(outblob, buf->data, buf->len); + + buf_burn(buf); + buf_free(buf); + buf = NULL; + + header = "-----BEGIN OPENSSH PRIVATE KEY-----\n"; + footer = "-----END OPENSSH PRIVATE KEY-----\n"; + } +#endif + /* * Padding on OpenSSH keys is deterministic. The number of * padding bytes is always more than zero, and always at most |