/* read about S2K at http://tools.ietf.org/html/rfc4880#section-3.7.1 */
static cdk_error_t
read_s2k (cdk_stream_t inp, cdk_s2k_t s2k)
{
size_t nread;
s2k->mode = cdk_stream_getc (inp);
s2k->hash_algo = cdk_stream_getc (inp);
if (s2k->mode == CDK_S2K_SIMPLE)
return 0;
else if (s2k->mode == CDK_S2K_SALTED || s2k->mode == CDK_S2K_ITERSALTED)
{
if (stream_read (inp, s2k->salt, DIM (s2k->salt), &nread))
return CDK_Inv_Packet;
if (nread != DIM (s2k->salt))
return CDK_Inv_Packet;
if (s2k->mode == CDK_S2K_ITERSALTED)
s2k->count = cdk_stream_getc (inp);
}
else if (s2k->mode == CDK_S2K_GNU_EXT)
{
/* GNU extensions to the S2K : read DETAILS from gnupg */
return 0;
}
else
return CDK_Not_Implemented;
return 0;
}
/* Read a new CTB and decode the body length. */
static void
read_new_length (cdk_stream_t inp,
size_t * r_len, size_t * r_size, size_t * r_partial)
{
int c, c1;
c = cdk_stream_getc (inp);
(*r_size)++;
if (c < 192)
*r_len = c;
else if (c >= 192 && c <= 223)
{
c1 = cdk_stream_getc (inp);
(*r_size)++;
*r_len = ((c - 192) << 8) + c1 + 192;
}
else if (c == 255)
{
*r_len = read_32 (inp);
(*r_size) += 4;
}
else
{
*r_len = 1 << (c & 0x1f);
*r_partial = 1;
}
}
static cdk_error_t
read_pubkey_enc (cdk_stream_t inp, size_t pktlen, cdk_pkt_pubkey_enc_t pke)
{
size_t i, nenc;
if (!inp || !pke)
return CDK_Inv_Value;
if (DEBUG_PKT)
_cdk_log_debug ("read_pubkey_enc: %d octets\n", pktlen);
if (pktlen < 12)
return CDK_Inv_Packet;
pke->version = cdk_stream_getc (inp);
if (pke->version < 2 || pke->version > 3)
return CDK_Inv_Packet;
pke->keyid[0] = read_32 (inp);
pke->keyid[1] = read_32 (inp);
if (!pke->keyid[0] && !pke->keyid[1])
pke->throw_keyid = 1; /* RFC2440 "speculative" keyID */
pke->pubkey_algo = _pgp_pub_algo_to_cdk (cdk_stream_getc (inp));
nenc = cdk_pk_get_nenc (pke->pubkey_algo);
if (!nenc)
return CDK_Inv_Algo;
for (i = 0; i < nenc; i++)
{
cdk_error_t rc = read_mpi (inp, &pke->mpi[i], 0);
if (rc)
return rc;
}
return 0;
}
static cdk_error_t
read_subpkt (cdk_stream_t inp, cdk_subpkt_t * r_ctx, size_t * r_nbytes)
{
byte c, c1;
size_t size, nread, n;
cdk_subpkt_t node;
cdk_error_t rc;
if (!inp || !r_nbytes)
return CDK_Inv_Value;
if (DEBUG_PKT)
_cdk_log_debug ("read_subpkt:\n");
n = 0;
*r_nbytes = 0;
c = cdk_stream_getc (inp);
n++;
if (c == 255)
{
size = read_32 (inp);
n += 4;
}
else if (c >= 192 && c < 255)
{
c1 = cdk_stream_getc (inp);
n++;
if (c1 == 0)
return 0;
size = ((c - 192) << 8) + c1 + 192;
}
else if (c < 192)
size = c;
else
return CDK_Inv_Packet;
node = cdk_subpkt_new (size);
if (!node)
return CDK_Out_Of_Core;
node->size = size;
node->type = cdk_stream_getc (inp);
if (DEBUG_PKT)
_cdk_log_debug (" %d octets %d type\n", node->size, node->type);
n++;
node->size--;
rc = stream_read (inp, node->d, node->size, &nread);
n += nread;
if (rc)
return rc;
*r_nbytes = n;
if (!*r_ctx)
*r_ctx = node;
else
cdk_subpkt_add (*r_ctx, node);
return rc;
}
/* Read an old packet CTB and return the length of the body. */
static void
read_old_length (cdk_stream_t inp, int ctb, size_t * r_len, size_t * r_size)
{
int llen = ctb & 0x03;
if (llen == 0)
{
*r_len = cdk_stream_getc (inp);
(*r_size)++;
}
else if (llen == 1)
{
*r_len = read_16 (inp);
(*r_size) += 2;
}
else if (llen == 2)
{
*r_len = read_32 (inp);
(*r_size) += 4;
}
else
{
*r_len = 0;
*r_size = 0;
}
}
static cdk_error_t
read_public_key (cdk_stream_t inp, size_t pktlen, cdk_pkt_pubkey_t pk)
{
size_t i, ndays, npkey;
if (!inp || !pk)
return CDK_Inv_Value;
if (DEBUG_PKT)
_cdk_log_debug ("read_public_key: %d octets\n", pktlen);
pk->is_invalid = 1; /* default to detect missing self signatures */
pk->is_revoked = 0;
pk->has_expired = 0;
pk->version = cdk_stream_getc (inp);
if (pk->version < 2 || pk->version > 4)
return CDK_Inv_Packet_Ver;
pk->timestamp = read_32 (inp);
if (pk->version < 4)
{
ndays = read_16 (inp);
if (ndays)
pk->expiredate = pk->timestamp + ndays * 86400L;
}
pk->pubkey_algo = _pgp_pub_algo_to_cdk (cdk_stream_getc (inp));
npkey = cdk_pk_get_npkey (pk->pubkey_algo);
if (!npkey)
{
gnutls_assert ();
_cdk_log_debug ("invalid public key algorithm %d\n", pk->pubkey_algo);
return CDK_Inv_Algo;
}
for (i = 0; i < npkey; i++)
{
cdk_error_t rc = read_mpi (inp, &pk->mpi[i], 0);
if (rc)
return rc;
}
/* This value is just for the first run and will be
replaced with the actual key flags from the self signature. */
pk->pubkey_usage = 0;
return 0;
}
static cdk_error_t
read_literal (cdk_stream_t inp, size_t pktlen,
cdk_pkt_literal_t * ret_pt, int is_partial)
{
cdk_pkt_literal_t pt = *ret_pt;
size_t nread;
cdk_error_t rc;
if (!inp || !pt)
return CDK_Inv_Value;
if (DEBUG_PKT)
_cdk_log_debug ("read_literal: %d octets\n", pktlen);
pt->mode = cdk_stream_getc (inp);
if (pt->mode != 0x62 && pt->mode != 0x74 && pt->mode != 0x75)
return CDK_Inv_Packet;
if (cdk_stream_eof (inp))
return CDK_Inv_Packet;
pt->namelen = cdk_stream_getc (inp);
if (pt->namelen > 0)
{
*ret_pt = pt = cdk_realloc (pt, sizeof *pt + pt->namelen + 2);
if (!pt)
return CDK_Out_Of_Core;
pt->name = (char*)pt + sizeof(*pt);
rc = stream_read (inp, pt->name, pt->namelen, &nread);
if (rc)
return rc;
if ((int) nread != pt->namelen)
return CDK_Inv_Packet;
pt->name[pt->namelen] = '\0';
}
pt->timestamp = read_32 (inp);
pktlen = pktlen - 6 - pt->namelen;
if (is_partial)
_cdk_stream_set_blockmode (inp, pktlen);
pt->buf = inp;
pt->len = pktlen;
return 0;
}
static cdk_error_t
read_onepass_sig (cdk_stream_t inp, size_t pktlen, cdk_pkt_onepass_sig_t sig)
{
if (!inp || !sig)
return CDK_Inv_Value;
if (DEBUG_PKT)
_cdk_log_debug ("read_onepass_sig: %d octets\n", pktlen);
if (pktlen != 13)
return CDK_Inv_Packet;
sig->version = cdk_stream_getc (inp);
if (sig->version != 3)
return CDK_Inv_Packet_Ver;
sig->sig_class = cdk_stream_getc (inp);
sig->digest_algo = _pgp_hash_algo_to_gnutls (cdk_stream_getc (inp));
sig->pubkey_algo = _pgp_pub_algo_to_cdk (cdk_stream_getc (inp));
sig->keyid[0] = read_32 (inp);
sig->keyid[1] = read_32 (inp);
sig->last = cdk_stream_getc (inp);
return 0;
}
int
_cdk_stream_gets( cdk_stream_t s, char * buf, size_t count )
{
int c, i = 0;
if( !s )
return CDK_Inv_Value;
while( !cdk_stream_eof( s ) && count > 0 ) {
c = cdk_stream_getc( s );
if( c == EOF || c == '\r' || c == '\n' ) {
buf[i++] = '\0';
break;
}
buf[i++] = c;
count--;
}
return i;
}
static cdk_error_t
read_compressed (cdk_stream_t inp, size_t pktlen, cdk_pkt_compressed_t c)
{
if (!inp || !c)
return CDK_Inv_Value;
if (DEBUG_PKT)
_cdk_log_debug ("read_compressed: %d octets\n", pktlen);
c->algorithm = cdk_stream_getc (inp);
if (c->algorithm > 3)
return CDK_Inv_Packet;
/* don't know the size, so we read until EOF */
if (!pktlen)
{
c->len = 0;
c->buf = inp;
}
/* FIXME: Support partial bodies. */
return 0;
}
/**
* cdk_pkt_read:
* @inp: the input stream
* @pkt: allocated packet handle to store the packet
*
* Parse the next packet on the @inp stream and return its contents in @pkt.
**/
cdk_error_t
cdk_pkt_read (cdk_stream_t inp, cdk_packet_t pkt)
{
int ctb, is_newctb;
int pkttype;
size_t pktlen = 0, pktsize = 0, is_partial = 0;
cdk_error_t rc;
if (!inp || !pkt)
return CDK_Inv_Value;
ctb = cdk_stream_getc (inp);
if (cdk_stream_eof (inp) || ctb == EOF)
return CDK_EOF;
else if (!ctb)
return CDK_Inv_Packet;
pktsize++;
if (!(ctb & 0x80))
{
_cdk_log_info ("cdk_pkt_read: no openpgp data found. "
"(ctb=%02X; fpos=%02X)\n", ctb, cdk_stream_tell (inp));
return CDK_Inv_Packet;
}
if (ctb & 0x40) /* RFC2440 packet format. */
{
pkttype = ctb & 0x3f;
is_newctb = 1;
}
else /* the old RFC1991 packet format. */
{
pkttype = ctb & 0x3f;
pkttype >>= 2;
is_newctb = 0;
}
if (pkttype > 63)
{
_cdk_log_info ("cdk_pkt_read: unknown type %d\n", pkttype);
return CDK_Inv_Packet;
}
if (is_newctb)
read_new_length (inp, &pktlen, &pktsize, &is_partial);
else
read_old_length (inp, ctb, &pktlen, &pktsize);
pkt->pkttype = pkttype;
pkt->pktlen = pktlen;
pkt->pktsize = pktsize + pktlen;
pkt->old_ctb = is_newctb ? 0 : 1;
rc = 0;
switch (pkt->pkttype)
{
case CDK_PKT_ATTRIBUTE:
pkt->pkt.user_id = cdk_calloc (1, sizeof *pkt->pkt.user_id
+ pkt->pktlen + 16 + 1);
if (!pkt->pkt.user_id)
return CDK_Out_Of_Core;
pkt->pkt.user_id->name = (char*)pkt->pkt.user_id + sizeof(*pkt->pkt.user_id);
rc = read_attribute (inp, pktlen, pkt->pkt.user_id);
pkt->pkttype = CDK_PKT_ATTRIBUTE;
break;
case CDK_PKT_USER_ID:
pkt->pkt.user_id = cdk_calloc (1, sizeof *pkt->pkt.user_id
+ pkt->pktlen + 1);
if (!pkt->pkt.user_id)
return CDK_Out_Of_Core;
pkt->pkt.user_id->name = (char*)pkt->pkt.user_id + sizeof(*pkt->pkt.user_id);
rc = read_user_id (inp, pktlen, pkt->pkt.user_id);
break;
case CDK_PKT_PUBLIC_KEY:
pkt->pkt.public_key = cdk_calloc (1, sizeof *pkt->pkt.public_key);
if (!pkt->pkt.public_key)
return CDK_Out_Of_Core;
rc = read_public_key (inp, pktlen, pkt->pkt.public_key);
break;
case CDK_PKT_PUBLIC_SUBKEY:
pkt->pkt.public_key = cdk_calloc (1, sizeof *pkt->pkt.public_key);
if (!pkt->pkt.public_key)
return CDK_Out_Of_Core;
rc = read_public_subkey (inp, pktlen, pkt->pkt.public_key);
break;
case CDK_PKT_SECRET_KEY:
pkt->pkt.secret_key = cdk_calloc (1, sizeof *pkt->pkt.secret_key);
if (!pkt->pkt.secret_key)
return CDK_Out_Of_Core;
pkt->pkt.secret_key->pk = cdk_calloc (1,
sizeof *pkt->pkt.secret_key->pk);
if (!pkt->pkt.secret_key->pk)
return CDK_Out_Of_Core;
rc = read_secret_key (inp, pktlen, pkt->pkt.secret_key);
break;
case CDK_PKT_SECRET_SUBKEY:
pkt->pkt.secret_key = cdk_calloc (1, sizeof *pkt->pkt.secret_key);
if (!pkt->pkt.secret_key)
return CDK_Out_Of_Core;
pkt->pkt.secret_key->pk = cdk_calloc (1,
sizeof *pkt->pkt.secret_key->pk);
if (!pkt->pkt.secret_key->pk)
return CDK_Out_Of_Core;
rc = read_secret_subkey (inp, pktlen, pkt->pkt.secret_key);
break;
case CDK_PKT_LITERAL:
pkt->pkt.literal = cdk_calloc (1, sizeof *pkt->pkt.literal);
if (!pkt->pkt.literal)
return CDK_Out_Of_Core;
rc = read_literal (inp, pktlen, &pkt->pkt.literal, is_partial);
break;
case CDK_PKT_ONEPASS_SIG:
pkt->pkt.onepass_sig = cdk_calloc (1, sizeof *pkt->pkt.onepass_sig);
if (!pkt->pkt.onepass_sig)
return CDK_Out_Of_Core;
rc = read_onepass_sig (inp, pktlen, pkt->pkt.onepass_sig);
break;
case CDK_PKT_SIGNATURE:
pkt->pkt.signature = cdk_calloc (1, sizeof *pkt->pkt.signature);
if (!pkt->pkt.signature)
return CDK_Out_Of_Core;
rc = read_signature (inp, pktlen, pkt->pkt.signature);
break;
case CDK_PKT_PUBKEY_ENC:
pkt->pkt.pubkey_enc = cdk_calloc (1, sizeof *pkt->pkt.pubkey_enc);
if (!pkt->pkt.pubkey_enc)
return CDK_Out_Of_Core;
rc = read_pubkey_enc (inp, pktlen, pkt->pkt.pubkey_enc);
break;
case CDK_PKT_COMPRESSED:
pkt->pkt.compressed = cdk_calloc (1, sizeof *pkt->pkt.compressed);
if (!pkt->pkt.compressed)
return CDK_Out_Of_Core;
rc = read_compressed (inp, pktlen, pkt->pkt.compressed);
break;
case CDK_PKT_MDC:
pkt->pkt.mdc = cdk_calloc (1, sizeof *pkt->pkt.mdc);
if (!pkt->pkt.mdc)
return CDK_Out_Of_Core;
rc = read_mdc (inp, pkt->pkt.mdc);
break;
default:
/* Skip all packets we don't understand */
skip_packet (inp, pktlen);
break;
}
return rc;
}
static cdk_error_t
read_signature (cdk_stream_t inp, size_t pktlen, cdk_pkt_signature_t sig)
{
size_t nbytes;
size_t i, size, nsig;
cdk_error_t rc;
if (!inp || !sig)
return CDK_Inv_Value;
if (DEBUG_PKT)
_cdk_log_debug ("read_signature: %d octets\n", pktlen);
if (pktlen < 16)
return CDK_Inv_Packet;
sig->version = cdk_stream_getc (inp);
if (sig->version < 2 || sig->version > 4)
return CDK_Inv_Packet_Ver;
sig->flags.exportable = 1;
sig->flags.revocable = 1;
if (sig->version < 4)
{
if (cdk_stream_getc (inp) != 5)
return CDK_Inv_Packet;
sig->sig_class = cdk_stream_getc (inp);
sig->timestamp = read_32 (inp);
sig->keyid[0] = read_32 (inp);
sig->keyid[1] = read_32 (inp);
sig->pubkey_algo = _pgp_pub_algo_to_cdk (cdk_stream_getc (inp));
sig->digest_algo = _pgp_hash_algo_to_gnutls (cdk_stream_getc (inp));
sig->digest_start[0] = cdk_stream_getc (inp);
sig->digest_start[1] = cdk_stream_getc (inp);
nsig = cdk_pk_get_nsig (sig->pubkey_algo);
if (!nsig)
return CDK_Inv_Algo;
for (i = 0; i < nsig; i++)
{
rc = read_mpi (inp, &sig->mpi[i], 0);
if (rc)
return rc;
}
}
else
{
sig->sig_class = cdk_stream_getc (inp);
sig->pubkey_algo = _pgp_pub_algo_to_cdk (cdk_stream_getc (inp));
sig->digest_algo = _pgp_hash_algo_to_gnutls (cdk_stream_getc (inp));
sig->hashed_size = read_16 (inp);
size = sig->hashed_size;
sig->hashed = NULL;
while (size > 0)
{
rc = read_subpkt (inp, &sig->hashed, &nbytes);
if (rc)
return rc;
size -= nbytes;
}
sig->unhashed_size = read_16 (inp);
size = sig->unhashed_size;
sig->unhashed = NULL;
while (size > 0)
{
rc = read_subpkt (inp, &sig->unhashed, &nbytes);
if (rc)
return rc;
size -= nbytes;
}
rc = parse_sig_subpackets (sig);
if (rc)
return rc;
sig->digest_start[0] = cdk_stream_getc (inp);
sig->digest_start[1] = cdk_stream_getc (inp);
nsig = cdk_pk_get_nsig (sig->pubkey_algo);
if (!nsig)
return CDK_Inv_Algo;
for (i = 0; i < nsig; i++)
{
rc = read_mpi (inp, &sig->mpi[i], 0);
if (rc)
return rc;
}
}
return 0;
}
static cdk_error_t
read_secret_key (cdk_stream_t inp, size_t pktlen, cdk_pkt_seckey_t sk)
{
size_t p1, p2, nread;
int i, nskey;
int rc;
if (!inp || !sk || !sk->pk)
return CDK_Inv_Value;
if (DEBUG_PKT)
_cdk_log_debug ("read_secret_key: %d octets\n", pktlen);
p1 = cdk_stream_tell (inp);
rc = read_public_key (inp, pktlen, sk->pk);
if (rc)
return rc;
sk->s2k_usage = cdk_stream_getc (inp);
sk->protect.sha1chk = 0;
if (sk->s2k_usage == 254 || sk->s2k_usage == 255)
{
sk->protect.sha1chk = (sk->s2k_usage == 254);
sk->protect.algo = _pgp_cipher_to_gnutls (cdk_stream_getc (inp));
sk->protect.s2k = cdk_calloc (1, sizeof *sk->protect.s2k);
if (!sk->protect.s2k)
return CDK_Out_Of_Core;
rc = read_s2k (inp, sk->protect.s2k);
if (rc)
return rc;
/* refer to --export-secret-subkeys in gpg(1) */
if (sk->protect.s2k->mode == CDK_S2K_GNU_EXT)
sk->protect.ivlen = 0;
else
{
sk->protect.ivlen =
_gnutls_cipher_get_block_size (sk->protect.algo);
if (!sk->protect.ivlen)
return CDK_Inv_Packet;
rc = stream_read (inp, sk->protect.iv, sk->protect.ivlen, &nread);
if (rc)
return rc;
if (nread != sk->protect.ivlen)
return CDK_Inv_Packet;
}
}
else
sk->protect.algo = _pgp_cipher_to_gnutls (sk->s2k_usage);
if (sk->protect.algo == GNUTLS_CIPHER_NULL)
{
sk->csum = 0;
nskey = cdk_pk_get_nskey (sk->pk->pubkey_algo);
if (!nskey)
{
gnutls_assert ();
return CDK_Inv_Algo;
}
for (i = 0; i < nskey; i++)
{
rc = read_mpi (inp, &sk->mpi[i], 1);
if (rc)
return rc;
}
sk->csum = read_16 (inp);
sk->is_protected = 0;
}
else if (sk->pk->version < 4)
{
/* The length of each multiprecision integer is stored in plaintext. */
nskey = cdk_pk_get_nskey (sk->pk->pubkey_algo);
if (!nskey)
{
gnutls_assert ();
return CDK_Inv_Algo;
}
for (i = 0; i < nskey; i++)
{
rc = read_mpi (inp, &sk->mpi[i], 1);
if (rc)
return rc;
}
sk->csum = read_16 (inp);
sk->is_protected = 1;
}
else
{
/* We need to read the rest of the packet because we do not
have any information how long the encrypted mpi's are */
p2 = cdk_stream_tell (inp);
p2 -= p1;
sk->enclen = pktlen - p2;
if (sk->enclen < 2)
return CDK_Inv_Packet; /* at least 16 bits for the checksum! */
sk->encdata = cdk_calloc (1, sk->enclen + 1);
if (!sk->encdata)
return CDK_Out_Of_Core;
if (stream_read (inp, sk->encdata, sk->enclen, &nread))
return CDK_Inv_Packet;
/* Handle the GNU S2K extensions we know (just gnu-dummy right now): */
if (sk->protect.s2k->mode == CDK_S2K_GNU_EXT)
{
unsigned char gnumode;
if ((sk->enclen < strlen ("GNU") + 1) ||
(0 != memcmp ("GNU", sk->encdata, strlen ("GNU"))))
return CDK_Inv_Packet;
gnumode = sk->encdata[strlen ("GNU")];
/* we only handle gnu-dummy (mode 1).
mode 2 should refer to external smart cards.
*/
if (gnumode != 1)
return CDK_Inv_Packet;
/* gnu-dummy should have no more data */
if (sk->enclen != strlen ("GNU") + 1)
return CDK_Inv_Packet;
}
nskey = cdk_pk_get_nskey (sk->pk->pubkey_algo);
if (!nskey)
{
gnutls_assert ();
return CDK_Inv_Algo;
}
/* We mark each MPI entry with NULL to indicate a protected key. */
for (i = 0; i < nskey; i++)
sk->mpi[i] = NULL;
sk->is_protected = 1;
}
sk->is_primary = 1;
_cdk_copy_pk_to_sk (sk->pk, sk);
return 0;
}
