From 0df336e34f379c9d4db2560039364fc5635a916d Mon Sep 17 00:00:00 2001
From: Nickolay Olshevsky <o.nickolay@gmail.com>
Date: Tue, 17 Sep 2024 14:41:12 +0300
Subject: [PATCH] (WIP) FFI: Add API to retrieve raw subpacket data.

---
 include/rnp/rnp.h        | 19 +++++++++++++++++
 include/rnp/rnp_err.h    |  1 +
 src/lib/ffi-priv-types.h | 12 +++++++++++
 src/lib/rnp.cpp          | 46 ++++++++++++++++++++++++++++++++++++++++
 4 files changed, 78 insertions(+)

diff --git a/include/rnp/rnp.h b/include/rnp/rnp.h
index b364d401d4..cfbb5b9995 100644
--- a/include/rnp/rnp.h
+++ b/include/rnp/rnp.h
@@ -256,6 +256,7 @@ typedef struct rnp_op_encrypt_st *         rnp_op_encrypt_t;
 typedef struct rnp_identifier_iterator_st *rnp_identifier_iterator_t;
 typedef struct rnp_uid_handle_st *         rnp_uid_handle_t;
 typedef struct rnp_signature_handle_st *   rnp_signature_handle_t;
+typedef struct rnp_sig_subpacket_st *      rnp_sig_subpacket_t;
 typedef struct rnp_recipient_handle_st *   rnp_recipient_handle_t;
 typedef struct rnp_symenc_handle_st *      rnp_symenc_handle_t;
 
@@ -1893,6 +1894,24 @@ RNP_API rnp_result_t rnp_signature_get_hash_alg(rnp_signature_handle_t sig, char
  */
 RNP_API rnp_result_t rnp_signature_get_creation(rnp_signature_handle_t sig, uint32_t *create);
 
+RNP_API rnp_result_t rnp_signature_subpacket_first(rnp_signature_handle_t sig,
+                                                   uint8_t                type,
+                                                   bool                   hashed,
+                                                   rnp_sig_subpacket_t *  subpkt);
+
+RNP_API rnp_result_t rnp_signature_subpacket_next(rnp_sig_subpacket_t *subpkt);
+
+RNP_API rnp_result_t rnp_signature_subpacket_info(rnp_sig_subpacket_t subpkt,
+                                                  uint8_t *           type,
+                                                  bool *              hashed,
+                                                  bool *              critical);
+
+RNP_API rnp_result_t rnp_signature_subpacket_data(rnp_sig_subpacket_t subpkt,
+                                                  uint8_t **          data,
+                                                  size_t *            size);
+
+RNP_API rnp_result_t rnp_signature_subpacket_destroy(rnp_sig_subpacket_t subpkt);
+
 /** Get the signature expiration time as number of seconds after creation time
  *
  * @param sig signature handle.
diff --git a/include/rnp/rnp_err.h b/include/rnp/rnp_err.h
index 49bef4f471..7cf36c0245 100644
--- a/include/rnp/rnp_err.h
+++ b/include/rnp/rnp_err.h
@@ -42,6 +42,7 @@ enum {
     RNP_ERROR_OUT_OF_MEMORY,
     RNP_ERROR_SHORT_BUFFER,
     RNP_ERROR_NULL_POINTER,
+    RNP_ERROR_NOT_FOUND,
 
     /* Storage */
     RNP_ERROR_ACCESS = 0x11000000,
diff --git a/src/lib/ffi-priv-types.h b/src/lib/ffi-priv-types.h
index 97f012748f..04fcde13e1 100644
--- a/src/lib/ffi-priv-types.h
+++ b/src/lib/ffi-priv-types.h
@@ -67,6 +67,18 @@ struct rnp_signature_handle_st {
     bool new_sig;
 };
 
+struct rnp_sig_subpacket_st {
+    const pgp_signature_t &sig;
+    bool                   hashed;
+    uint8_t                type;
+    size_t                 idx;
+
+    rnp_sig_subpacket_st(const pgp_signature_t &asig)
+        : sig(asig), hashed(true), type(0), idx(0)
+    {
+    }
+};
+
 struct rnp_recipient_handle_st {
     rnp_ffi_t        ffi;
     pgp_key_id_t     keyid;
diff --git a/src/lib/rnp.cpp b/src/lib/rnp.cpp
index b54640826a..b2589bc6ad 100644
--- a/src/lib/rnp.cpp
+++ b/src/lib/rnp.cpp
@@ -6650,6 +6650,52 @@ try {
 }
 FFI_GUARD
 
+rnp_result_t
+rnp_signature_subpacket_first(rnp_signature_handle_t sig,
+                              uint8_t                type,
+                              bool                   hashed,
+                              rnp_sig_subpacket_t *  subpkt)
+try {
+    if (!sig || !subpkt) {
+        return RNP_ERROR_NULL_POINTER;
+    }
+    return RNP_ERROR_NOT_IMPLEMENTED;
+}
+FFI_GUARD
+
+rnp_result_t
+rnp_signature_subpacket_next(rnp_sig_subpacket_t *subpkt)
+try {
+    if (!subpkt) {
+        return RNP_ERROR_NULL_POINTER;
+    }
+    return RNP_ERROR_NOT_IMPLEMENTED;
+}
+FFI_GUARD
+
+rnp_result_t
+rnp_signature_subpacket_info(rnp_sig_subpacket_t subpkt,
+                             uint8_t *           type,
+                             bool *              hashed,
+                             bool *              critical)
+try {
+    if (!subpkt) {
+        return RNP_ERROR_NULL_POINTER;
+    }
+    return RNP_ERROR_NOT_IMPLEMENTED;
+}
+FFI_GUARD
+
+rnp_result_t
+rnp_signature_subpacket_data(rnp_sig_subpacket_t subpkt, uint8_t **data, size_t *size)
+try {
+    if (!subpkt) {
+        return RNP_ERROR_NULL_POINTER;
+    }
+    return RNP_ERROR_NOT_IMPLEMENTED;
+}
+FFI_GUARD
+
 rnp_result_t
 rnp_signature_get_expiration(rnp_signature_handle_t handle, uint32_t *expires)
 try {