MONGOCRYPT-758 Implement FLE2IndexedTextEncryptedValue parse & decrypt

src/mc-fle-blob-subtype-private.h

@@ -42,7 +42,10 @@ typedef enum {
     MC_SUBTYPE_FLE2FindRangePayloadV2 = 13,
     MC_SUBTYPE_FLE2IndexedEqualityEncryptedValueV2 = 14,
     MC_SUBTYPE_FLE2IndexedRangeEncryptedValueV2 = 15,
-    MC_SUBTYPE_FLE2UnindexedEncryptedValueV2 = 16
+    MC_SUBTYPE_FLE2UnindexedEncryptedValueV2 = 16,
+
+    /* Text Search Subtypes */
+    MC_SUBTYPE_FLE2IndexedTextEncryptedValue = 17,
 } mc_fle_blob_subtype_t;
 
 #endif /* MC_FLE_BLOB_SUBTYPE_PRIVATE_H */

src/mc-fle2-payload-iev-private-v2.h

@@ -24,7 +24,7 @@
 #include "mongocrypt-status-private.h"
 
 /*
- * FLE2IndexedEqualityEncryptedValueV2 and FLE2IndexedRangeEncryptedValueV2
+ * FLE2IndexedEqualityEncryptedValueV2, FLE2IndexedRangeEncryptedValueV2, and FLEIndexedTextEncryptedValue
  * share a common internal implementation.
  *
  * Lifecycle:
@@ -78,19 +78,43 @@
  * 1/ `edge_count` is introduced as an octet following `original_bson_type`.
  * 2/ Rather than a single metadata block, we have {edge_count} blocks.
  *
+ * FLE2IndexedTextEncryptedValue has the following data layout:
+ *
+ * struct FLE2IndexedTextEncryptedValue {
+ *   uint8_t fle_blob_subtype = 17;
+ *   uint8_t S_KeyId[16];
+ *   uint8_t original_bson_type;
+ *   uint8_t edge_count;
+ *   uint8_t substr_tag_count;
+ *   uint8_t suffix_tag_count;
+ *   uint8_t ServerEncryptedValue[ServerEncryptedValue.length];
+ *   FLE2TagAndEncryptedMetadataBlock exact_metadata;
+ *   FLE2TagAndEncryptedMetadataBlock substr_metadata[substr_tag_count];
+ *   FLE2TagAndEncryptedMetadataBlock suffix_metadata[suffix_tag_count];
+ *   FLE2TagAndEncryptedMetadataBlock prefix_metadata[edge_count - suffix_tag_count - substr_tag_count - 1];
+ * }
+ * The main difference in this format is that we split `metadata` into 4
+ * sections, one for each text search index type. We add two octets,
+ * `substr_tag_count` and `suffix_tag_count`, following `edge_count`
+ * in order to track the delineation of the metadata. Similarly to
+ * FLE2IndexedEqualityEncryptedValueV2, we have `edge_count` total
+ * blocks.
  */
 
 typedef enum {
     kFLE2IEVTypeInitV2,
     kFLE2IEVTypeEqualityV2,
     kFLE2IEVTypeRangeV2,
+    kFLE2IEVTypeText,
 } _mc_fle2_iev_v2_type;
 
 typedef struct _mc_FLE2IndexedEncryptedValueV2_t {
     // Raw payload values
     uint8_t fle_blob_subtype;
     uint8_t bson_value_type;
     uint8_t edge_count;
+    uint8_t substr_tag_count;
+    uint8_t suffix_tag_count;
     _mongocrypt_buffer_t S_KeyId;
     _mongocrypt_buffer_t ServerEncryptedValue;
 
@@ -182,6 +206,15 @@ const _mongocrypt_buffer_t *mc_FLE2IndexedEncryptedValueV2_get_ClientValue(const
 uint8_t mc_FLE2IndexedEncryptedValueV2_get_edge_count(const mc_FLE2IndexedEncryptedValueV2_t *iev,
                                                       mongocrypt_status_t *status);
 
+uint8_t mc_FLE2IndexedEncryptedValueV2_get_substr_tag_count(const mc_FLE2IndexedEncryptedValueV2_t *iev,
+                                                            mongocrypt_status_t *status);
+
+uint8_t mc_FLE2IndexedEncryptedValueV2_get_suffix_tag_count(const mc_FLE2IndexedEncryptedValueV2_t *iev,
+                                                            mongocrypt_status_t *status);
+
+uint8_t mc_FLE2IndexedEncryptedValueV2_get_prefix_tag_count(const mc_FLE2IndexedEncryptedValueV2_t *iev,
+                                                            mongocrypt_status_t *status);
+
 bool mc_FLE2IndexedEncryptedValueV2_get_edge(const mc_FLE2IndexedEncryptedValueV2_t *iev,
                                              mc_FLE2TagAndEncryptedMetadataBlock_t *out,
                                              const uint8_t edge_index,
@@ -191,6 +224,25 @@ bool mc_FLE2IndexedEncryptedValueV2_get_metadata(const mc_FLE2IndexedEncryptedVa
                                                  mc_FLE2TagAndEncryptedMetadataBlock_t *out,
                                                  mongocrypt_status_t *status);
 
+bool mc_FLE2IndexedEncryptedValueV2_get_exact_metadata(const mc_FLE2IndexedEncryptedValueV2_t *iev,
+                                                       mc_FLE2TagAndEncryptedMetadataBlock_t *out,
+                                                       mongocrypt_status_t *status);
+
+bool mc_FLE2IndexedEncryptedValueV2_get_substr_metadata(const mc_FLE2IndexedEncryptedValueV2_t *iev,
+                                                        mc_FLE2TagAndEncryptedMetadataBlock_t *out,
+                                                        const uint8_t block_index,
+                                                        mongocrypt_status_t *status);
+
+bool mc_FLE2IndexedEncryptedValueV2_get_suffix_metadata(const mc_FLE2IndexedEncryptedValueV2_t *iev,
+                                                        mc_FLE2TagAndEncryptedMetadataBlock_t *out,
+                                                        const uint8_t block_index,
+                                                        mongocrypt_status_t *status);
+
+bool mc_FLE2IndexedEncryptedValueV2_get_prefix_metadata(const mc_FLE2IndexedEncryptedValueV2_t *iev,
+                                                        mc_FLE2TagAndEncryptedMetadataBlock_t *out,
+                                                        const uint8_t block_index,
+                                                        mongocrypt_status_t *status);
+
 void mc_FLE2IndexedEncryptedValueV2_destroy(mc_FLE2IndexedEncryptedValueV2_t *iev);
 
 #endif /* MONGOCRYPT_INDEXED_ENCRYPTED_VALUE_PRIVATE_V2_H */