+
+/* Take an MPI from a buffer and import it into a GMP mpz_t */
+#define MPI_TO_MPZ(pk, v) \
+{ \
+ /* MPI length is stored in bits, convert it to bytes */ \
+ if (pk->length < (ofs + 2)) { \
+ ret = ONAK_E_INVALID_PKT; \
+ } else { \
+ len = pk->data[ofs] << 8 | pk->data[ofs + 1]; \
+ len += 7; \
+ len = len >> 3; \
+ if (pk->length < (ofs + len + 2)) { \
+ ret = ONAK_E_INVALID_PKT; \
+ } else { \
+ mpz_import(v, len, 1, 1, 0, 0, &pk->data[ofs + 2]); \
+ ofs += len + 2; \
+ } \
+ } \
+}
+
+#if HAVE_CRYPTO
+
+/*
+ * Hold the crypto material for a public key.
+ * May want to move to a header at some point.
+ */
+struct onak_key_material {
+ uint8_t type;
+ union {
+ struct dsa_params dsa;
+ struct ecc_point ecc;
+ struct rsa_public_key rsa;
+ uint8_t ed25519[32];
+ };
+ mpz_t y;
+};
+
+static void onak_free_key_material(struct onak_key_material *key)
+{
+ switch (key->type) {
+ case OPENPGP_PKALGO_ECDSA:
+ ecc_point_clear(&key->ecc);
+ break;
+ case OPENPGP_PKALGO_DSA:
+ mpz_clear(key->dsa.p);
+ mpz_clear(key->dsa.q);
+ mpz_clear(key->dsa.g);
+ mpz_clear(key->y);
+ break;
+ case OPENPGP_PKALGO_RSA:
+ case OPENPGP_PKALGO_RSA_ENC:
+ case OPENPGP_PKALGO_RSA_SIGN:
+ mpz_clear(key->rsa.n);
+ mpz_clear(key->rsa.e);
+ break;
+ }
+
+ /* Set the key type back to 0 to indicate we cleared it */
+ key->type = 0;
+
+ return;
+}
+
+static onak_status_t onak_parse_key_material(struct openpgp_packet *pk,
+ struct onak_key_material *key)
+{
+ int len, ofs;
+ enum onak_oid oid;
+ mpz_t x, y;
+ onak_status_t ret = ONAK_E_OK;
+
+ /* Clear the key type; only set it when fully parsed */
+ key->type = 0;
+
+ /*
+ * Shortest valid key is v4 Ed25519, which takes 51 bytes, so do a
+ * quick sanity check which will ensure we have enough data to check
+ * the packet header and OID info.
+ */
+ if (pk->length < 51)
+ return ONAK_E_INVALID_PKT;
+
+ if (pk->data[0] != 4 && pk->data[0] != 5)
+ return ONAK_E_UNSUPPORTED_FEATURE;
+
+ /*
+ * MPIs are after version byte, 4 byte creation time +
+ * type byte plus length for v5.
+ */
+ ofs = (pk->data[0] == 4) ? 6 : 10;
+ switch (pk->data[5]) {
+ case OPENPGP_PKALGO_ECDSA:
+ oid = onak_parse_oid(&pk->data[ofs], pk->length - ofs);
+ if (oid == ONAK_OID_INVALID)
+ return ONAK_E_INVALID_PKT;
+ if (oid == ONAK_OID_UNKNOWN)
+ return ONAK_E_UNSUPPORTED_FEATURE;
+
+ if (oid == ONAK_OID_NISTP256) {
+ if (pk->length - ofs != 76)
+ return ONAK_E_INVALID_PKT;
+ /* Move past the OID to the key data MPI */
+ ofs += pk->data[ofs] + 1;
+ len = pk->data[ofs] << 8 | pk->data[ofs + 1];
+ if (len != 515)
+ return ONAK_E_INVALID_PKT;
+ if (pk->data[ofs + 2] != 4)
+ return ONAK_E_INVALID_PKT;
+ mpz_init(x);
+ mpz_init(y);
+ ecc_point_init(&key->ecc, nettle_get_secp_256r1());
+ ofs += 3;
+ mpz_import(x, 32, 1, 1, 0, 0, &pk->data[ofs]);
+ ofs += 32;
+ mpz_import(y, 32, 1, 1, 0, 0, &pk->data[ofs]);
+ ofs += 32;
+ ecc_point_set(&key->ecc, x, y);
+ } else if (oid == ONAK_OID_NISTP384) {
+ if (pk->length - ofs != 105)
+ return ONAK_E_INVALID_PKT;
+ /* Move past the OID to the key data MPI */
+ ofs += pk->data[ofs] + 1;
+ len = pk->data[ofs] << 8 | pk->data[ofs + 1];
+ if (len != 771)
+ return ONAK_E_INVALID_PKT;
+ if (pk->data[ofs + 2] != 4)
+ return ONAK_E_INVALID_PKT;
+ mpz_init(x);
+ mpz_init(y);
+ ecc_point_init(&key->ecc, nettle_get_secp_384r1());
+ ofs += 3;
+ mpz_import(x, 48, 1, 1, 0, 0, &pk->data[ofs]);
+ ofs += 48;
+ mpz_import(y, 48, 1, 1, 0, 0, &pk->data[ofs]);
+ ofs += 48;
+ ecc_point_set(&key->ecc, x, y);
+ } else if (oid == ONAK_OID_NISTP521) {
+ if (pk->length - ofs != 141)
+ return ONAK_E_INVALID_PKT;
+ /* Move past the OID to the key data MPI */
+ ofs += pk->data[ofs] + 1;
+ len = pk->data[ofs] << 8 | pk->data[ofs + 1];
+ if (len != 1059)
+ return ONAK_E_INVALID_PKT;
+ if (pk->data[ofs + 2] != 4)
+ return ONAK_E_INVALID_PKT;
+ mpz_init(x);
+ mpz_init(y);
+ ecc_point_init(&key->ecc, nettle_get_secp_521r1());
+ ofs += 3;
+ mpz_import(x, 66, 1, 1, 0, 0, &pk->data[ofs]);
+ ofs += 66;
+ mpz_import(y, 66, 1, 1, 0, 0, &pk->data[ofs]);
+ ofs += 66;
+ ecc_point_set(&key->ecc, x, y);
+ } else {
+ return ONAK_E_UNSUPPORTED_FEATURE;
+ }
+ mpz_clear(y);
+ mpz_clear(x);
+ break;
+ case OPENPGP_PKALGO_EDDSA:
+ if (pk->length - ofs != 45)
+ return ONAK_E_INVALID_PKT;
+ oid = onak_parse_oid(&pk->data[ofs], pk->length - ofs);
+ if (oid == ONAK_OID_INVALID)
+ return ONAK_E_INVALID_PKT;
+ if (oid == ONAK_OID_UNKNOWN)
+ return ONAK_E_UNSUPPORTED_FEATURE;
+
+ /* Move past the OID to the key data MPI */
+ ofs += pk->data[ofs] + 1;
+
+ if (oid == ONAK_OID_ED25519) {
+ len = pk->data[ofs] << 8 | pk->data[ofs + 1];
+ if (len != 263)
+ return ONAK_E_INVALID_PKT;
+ if (pk->data[ofs + 2] != 0x40)
+ return ONAK_E_INVALID_PKT;
+ ofs += 3;
+ memcpy(key->ed25519, &pk->data[ofs], 32);
+ ofs += 32;
+ } else {
+ return ONAK_E_UNSUPPORTED_FEATURE;
+ }
+ break;
+ case OPENPGP_PKALGO_DSA:
+ mpz_init(key->dsa.p);
+ mpz_init(key->dsa.q);
+ mpz_init(key->dsa.g);
+ mpz_init(key->y);
+ MPI_TO_MPZ(pk, key->dsa.p);
+ if (ret == ONAK_E_OK)
+ MPI_TO_MPZ(pk, key->dsa.q);
+ if (ret == ONAK_E_OK)
+ MPI_TO_MPZ(pk, key->dsa.g);
+ if (ret == ONAK_E_OK)
+ MPI_TO_MPZ(pk, key->y);
+ break;
+ case OPENPGP_PKALGO_RSA:
+ case OPENPGP_PKALGO_RSA_ENC:
+ case OPENPGP_PKALGO_RSA_SIGN:
+ mpz_init(key->rsa.n);
+ mpz_init(key->rsa.e);
+ key->rsa.size = ((pk->data[6] << 8) + pk->data[7] + 7) >> 3;
+ MPI_TO_MPZ(pk, key->rsa.n);
+ if (ret == ONAK_E_OK)
+ MPI_TO_MPZ(pk, key->rsa.e);
+ break;
+ default:
+ return ONAK_E_UNSUPPORTED_FEATURE;
+ }
+
+ /*
+ * Keep scan-build happy; we bump this in MPI_TO_MPZ and then don't use
+ * it again the last time we do so.
+ */
+ (void)ofs;
+
+ key->type = pk->data[5];
+
+ if (ret != ONAK_E_OK) {
+ onak_free_key_material(key);
+ }
+
+ return ret;
+}
+
+onak_status_t onak_check_hash_sig(struct openpgp_packet *sigkey,
+ struct openpgp_packet *sig,
+ uint8_t *hash,
+ uint8_t hashtype)
+{
+ onak_status_t ret;
+ struct onak_key_material pubkey;
+ struct dsa_signature dsasig;
+ uint8_t sigkeytype;
+ uint8_t edsig[64];
+ int len, ofs;
+ mpz_t s;
+
+ ret = onak_parse_key_material(sigkey, &pubkey);
+ if (ret != ONAK_E_OK) {
+ return ret;
+ }
+
+ /* Sanity check the length of the signature packet */
+ if (sig->length < 8) {
+ ret = ONAK_E_INVALID_PKT;
+ goto out;
+ }
+
+ if (sig->data[0] == 3) {
+ /* Must be 5 bytes hashed */
+ if (sig->data[1] != 5) {
+ ret = ONAK_E_INVALID_PARAM;
+ goto out;
+ }
+
+ /* Need at least 19 bytes for the sig header */
+ if (sig->length < 19) {
+ ret = ONAK_E_INVALID_PKT;
+ goto out;
+ }
+
+ /* Skip to the signature material */
+ ofs = 19;
+ sigkeytype = sig->data[15];
+ } else if (sig->data[0] >= 4) {
+ /* Skip the hashed data */
+ ofs = (sig->data[4] << 8) + sig->data[5] + 6;
+ if (sig->length < ofs + 2) {
+ ret = ONAK_E_INVALID_PKT;
+ goto out;
+ }
+ /* Skip the unhashed data */
+ ofs += (sig->data[ofs] << 8) + sig->data[ofs + 1] + 2;
+ if (sig->length < ofs + 2) {
+ ret = ONAK_E_INVALID_PKT;
+ goto out;
+ }
+ /* Skip the sig hash bytes */
+ ofs += 2;
+ sigkeytype = sig->data[2];
+ } else {
+ ret = ONAK_E_UNSUPPORTED_FEATURE;
+ goto out;
+ }
+
+ /* Is the key the same type as the signature we're checking? */
+ if (pubkey.type != sigkeytype) {
+ ret = ONAK_E_INVALID_PARAM;
+ goto out;
+ }
+
+ /* Parse the actual signature values */
+ switch (sigkeytype) {
+ case OPENPGP_PKALGO_ECDSA:
+ case OPENPGP_PKALGO_DSA:
+ mpz_init(dsasig.r);
+ mpz_init(dsasig.s);
+ MPI_TO_MPZ(sig, dsasig.r);
+ if (ret == ONAK_E_OK)
+ MPI_TO_MPZ(sig, dsasig.s);
+ break;
+ case OPENPGP_PKALGO_EDDSA:
+ mpz_init(dsasig.r);
+ mpz_init(dsasig.s);
+ MPI_TO_MPZ(sig, dsasig.r);
+ if (ret == ONAK_E_OK)
+ MPI_TO_MPZ(sig, dsasig.s);
+ mpz_export(edsig, NULL, 1, 1, 0, 0, dsasig.r);
+ mpz_export(&edsig[32], NULL, 1, 1, 0, 0, dsasig.s);
+ break;
+ case OPENPGP_PKALGO_RSA:
+ case OPENPGP_PKALGO_RSA_SIGN:
+ mpz_init(s);
+ MPI_TO_MPZ(sig, s);
+ break;
+ }
+
+ /* If we didn't parse the signature properly then do clean-up */
+ if (ret != ONAK_E_OK)
+ goto sigerr;
+
+ /* Squash a signing only RSA key to a standard RSA key for below */
+ if (pubkey.type == OPENPGP_PKALGO_RSA_SIGN) {
+ pubkey.type = OPENPGP_PKALGO_RSA;
+ }
+
+#define KEYHASH(key, hash) ((key << 8) | hash)
+
+ switch KEYHASH(pubkey.type, hashtype) {
+ case KEYHASH(OPENPGP_PKALGO_DSA, OPENPGP_HASH_MD5):
+ ret = dsa_verify(&pubkey.dsa, pubkey.y,
+ MD5_DIGEST_SIZE, hash, &dsasig) ?
+ ONAK_E_WEAK_SIGNATURE : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_DSA, OPENPGP_HASH_RIPEMD160):
+ ret = dsa_verify(&pubkey.dsa, pubkey.y,
+ RIPEMD160_DIGEST_SIZE, hash, &dsasig) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_DSA, OPENPGP_HASH_SHA1):
+ ret = dsa_verify(&pubkey.dsa, pubkey.y,
+ SHA1_DIGEST_SIZE, hash, &dsasig) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_DSA, OPENPGP_HASH_SHA1X):
+ ret = dsa_verify(&pubkey.dsa, pubkey.y,
+ SHA1X_DIGEST_SIZE, hash, &dsasig) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_DSA, OPENPGP_HASH_SHA224):
+ ret = dsa_verify(&pubkey.dsa, pubkey.y,
+ SHA224_DIGEST_SIZE, hash, &dsasig) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_DSA, OPENPGP_HASH_SHA256):
+ ret = dsa_verify(&pubkey.dsa, pubkey.y,
+ SHA256_DIGEST_SIZE, hash, &dsasig) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_DSA, OPENPGP_HASH_SHA384):
+ ret = dsa_verify(&pubkey.dsa, pubkey.y,
+ SHA384_DIGEST_SIZE, hash, &dsasig) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_DSA, OPENPGP_HASH_SHA512):
+ ret = dsa_verify(&pubkey.dsa, pubkey.y,
+ SHA512_DIGEST_SIZE, hash, &dsasig) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_ECDSA, OPENPGP_HASH_SHA1):
+ ret = ecdsa_verify(&pubkey.ecc,
+ SHA1_DIGEST_SIZE, hash, &dsasig) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_ECDSA, OPENPGP_HASH_SHA256):
+ ret = ecdsa_verify(&pubkey.ecc,
+ SHA256_DIGEST_SIZE, hash, &dsasig) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_ECDSA, OPENPGP_HASH_SHA384):
+ ret = ecdsa_verify(&pubkey.ecc,
+ SHA384_DIGEST_SIZE, hash, &dsasig) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_ECDSA, OPENPGP_HASH_SHA512):
+ ret = ecdsa_verify(&pubkey.ecc,
+ SHA512_DIGEST_SIZE, hash, &dsasig) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_EDDSA, OPENPGP_HASH_RIPEMD160):
+ ret = ed25519_sha512_verify(pubkey.ed25519,
+ RIPEMD160_DIGEST_SIZE, hash, edsig) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_EDDSA, OPENPGP_HASH_SHA256):
+ ret = ed25519_sha512_verify(pubkey.ed25519,
+ SHA256_DIGEST_SIZE, hash, edsig) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_EDDSA, OPENPGP_HASH_SHA384):
+ ret = ed25519_sha512_verify(pubkey.ed25519,
+ SHA384_DIGEST_SIZE, hash, edsig) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_EDDSA, OPENPGP_HASH_SHA512):
+ ret = ed25519_sha512_verify(pubkey.ed25519,
+ SHA512_DIGEST_SIZE, hash, edsig) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_RSA, OPENPGP_HASH_MD5):
+ ret = rsa_md5_verify_digest(&pubkey.rsa, hash, s) ?
+ ONAK_E_WEAK_SIGNATURE : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_RSA, OPENPGP_HASH_RIPEMD160):
+ ret = rsa_ripemd160_verify_digest(&pubkey.rsa, hash, s) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_RSA, OPENPGP_HASH_SHA1):
+ ret = rsa_sha1_verify_digest(&pubkey.rsa, hash, s) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_RSA, OPENPGP_HASH_SHA224):
+ ret = rsa_sha224_verify_digest(&pubkey.rsa, hash, s) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_RSA, OPENPGP_HASH_SHA256):
+ ret = rsa_sha256_verify_digest(&pubkey.rsa, hash, s) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_RSA, OPENPGP_HASH_SHA384):
+ ret = rsa_sha384_verify_digest(&pubkey.rsa, hash, s) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ case KEYHASH(OPENPGP_PKALGO_RSA, OPENPGP_HASH_SHA512):
+ ret = rsa_sha512_verify_digest(&pubkey.rsa, hash, s) ?
+ ONAK_E_OK : ONAK_E_BAD_SIGNATURE;
+ break;
+ default:
+ ret = ONAK_E_UNSUPPORTED_FEATURE;
+ }
+
+sigerr:
+ switch (sigkeytype) {
+ case OPENPGP_PKALGO_ECDSA:
+ case OPENPGP_PKALGO_EDDSA:
+ case OPENPGP_PKALGO_DSA:
+ mpz_clear(dsasig.r);
+ mpz_clear(dsasig.s);
+ break;
+ case OPENPGP_PKALGO_RSA:
+ case OPENPGP_PKALGO_RSA_SIGN:
+ mpz_clear(s);
+ break;
+ }
+
+out:
+ onak_free_key_material(&pubkey);
+
+ return ret;
+}
+
+#endif /* HAVE_CRYPTO */
+
+onak_status_t calculate_packet_sighash(struct openpgp_publickey *key,
+ struct openpgp_packet *packet,
+ struct openpgp_packet *sig,
+ uint8_t *hashtype,
+ uint8_t *hash,
+ uint8_t **sighash)
+{
+ size_t siglen, unhashedlen;
+ struct onak_hash_data hashdata;
+ uint8_t keyheader[5];