Reimplement PKCS #3 DH parameter parsing with crypto/bytestring.
Also add a test.
This is the last of the openssl/asn1.h includes from the directories that are
to be kept in the core libcrypto library. (What remains is to finish sorting
out the crypto/obj stuff. We'll also want to retain a decoupled version of the
PKCS#12 stuff.)
Functions that need to be audited for reuse:
i2d_DHparams
BUG=54
Change-Id: Ibef030a98d3a93ae26e8e56869f14858ec75601b
Reviewed-on: https://boringssl-review.googlesource.com/7900
Reviewed-by: Steven Valdez <svaldez@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
diff --git a/include/openssl/dh.h b/include/openssl/dh.h
index 5cdeb86..a087651 100644
--- a/include/openssl/dh.h
+++ b/include/openssl/dh.h
@@ -174,22 +174,15 @@
/* ASN.1 functions. */
-/* d2i_DHparams parses an ASN.1, DER encoded Diffie-Hellman parameters
- * structure from |len| bytes at |*inp|. If |ret| is not NULL then, on exit, a
- * pointer to the result is in |*ret|. If |*ret| is already non-NULL on entry
- * then the result is written directly into |*ret|, otherwise a fresh |DH| is
- * allocated. However, one should not depend on writing into |*ret| because
- * this behaviour is likely to change in the future.
- *
- * On successful exit, |*inp| is advanced past the DER structure. It
- * returns the result or NULL on error. */
-OPENSSL_EXPORT DH *d2i_DHparams(DH **ret, const unsigned char **inp, long len);
+/* DH_parse_parameters decodes a DER-encoded DHParameter structure (PKCS #3)
+ * from |cbs| and advances |cbs|. It returns a newly-allocated |DH| or NULL on
+ * error. */
+OPENSSL_EXPORT DH *DH_parse_parameters(CBS *cbs);
-/* i2d_DHparams marshals |in| to an ASN.1, DER structure. If |outp| is not NULL
- * then the result is written to |*outp| and |*outp| is advanced just past the
- * output. It returns the number of bytes in the result, whether written or
- * not, or a negative value on error. */
-OPENSSL_EXPORT int i2d_DHparams(const DH *in, unsigned char **outp);
+/* DH_marshal_parameters marshals |dh| as a DER-encoded DHParameter structure
+ * (PKCS #3) and appends the result to |cbb|. It returns one on success and zero
+ * on error. */
+OPENSSL_EXPORT int DH_marshal_parameters(CBB *cbb, const DH *dh);
/* ex_data functions.
@@ -213,6 +206,26 @@
void (*callback)(int, int, void *),
void *cb_arg);
+/* d2i_DHparams parses an ASN.1, DER encoded Diffie-Hellman parameters structure
+ * from |len| bytes at |*inp|. If |ret| is not NULL then, on exit, a pointer to
+ * the result is in |*ret|. Note that, even if |*ret| is already non-NULL on
+ * entry, it will not be written to. Rather, a fresh |DH| is allocated and the
+ * previous one is freed.
+ *
+ * On successful exit, |*inp| is advanced past the DER structure. It
+ * returns the result or NULL on error.
+ *
+ * Use |DH_parse_parameters| instead. */
+OPENSSL_EXPORT DH *d2i_DHparams(DH **ret, const unsigned char **inp, long len);
+
+/* i2d_DHparams marshals |in| to an ASN.1, DER structure. If |outp| is not NULL
+ * then the result is written to |*outp| and |*outp| is advanced just past the
+ * output. It returns the number of bytes in the result, whether written or
+ * not, or a negative value on error.
+ *
+ * Use |DH_marshal_parameters| instead. */
+OPENSSL_EXPORT int i2d_DHparams(const DH *in, unsigned char **outp);
+
struct dh_st {
BIGNUM *p;
@@ -248,5 +261,7 @@
#define DH_R_INVALID_PUBKEY 101
#define DH_R_MODULUS_TOO_LARGE 102
#define DH_R_NO_PRIVATE_VALUE 103
+#define DH_R_DECODE_ERROR 104
+#define DH_R_ENCODE_ERROR 105
#endif /* OPENSSL_HEADER_DH_H */
