tildefriends/src/ssb.db.c

#include "ssb.db.h"

#include "mem.h"
#include "ssb.h"
#include "trace.h"
#include "util.js.h"

#include <base64c.h>
#include <sodium/crypto_hash_sha256.h>
#include <sodium/crypto_scalarmult.h>
#include <sodium/crypto_scalarmult_curve25519.h>
#include <sodium/crypto_secretbox.h>
#include <sodium/crypto_sign.h>
#include <sqlite3.h>
#include <stdlib.h>
#include <string.h>

static void _tf_ssb_db_exec(sqlite3* db, const char* statement)
{
	char* error = NULL;
	int result = sqlite3_exec(db, statement, NULL, NULL, &error);
	if (result != SQLITE_OK)
	{
		printf("Error running '%s': %s.\n", statement, error);
		abort();
	}
}

void tf_ssb_db_init(tf_ssb_t* ssb)
{
	sqlite3* db = tf_ssb_get_db(ssb);
	_tf_ssb_db_exec(db, "PRAGMA journal_mode = WAL");
	_tf_ssb_db_exec(db, "PRAGMA synchronous = NORMAL");
	_tf_ssb_db_exec(db,
		"CREATE TABLE IF NOT EXISTS messages ("
		"  author TEXT,"
		"  id TEXT PRIMARY KEY,"
		"  sequence INTEGER,"
		"  timestamp REAL,"
		"  previous TEXT,"
		"  hash TEXT,"
		"  content TEXT,"
		"  signature TEXT,"
		"  sequence_before_author INTEGER,"
		"  UNIQUE(author, sequence)"
		")");
	_tf_ssb_db_exec(db, "CREATE INDEX IF NOT EXISTS messages_author_id_index ON messages (author, id)");
	_tf_ssb_db_exec(db, "CREATE INDEX IF NOT EXISTS messages_author_sequence_index ON messages (author, sequence)");
	_tf_ssb_db_exec(db, "CREATE INDEX IF NOT EXISTS messages_author_timestamp_index ON messages (author, timestamp)");
	_tf_ssb_db_exec(db,
		"CREATE TABLE IF NOT EXISTS blobs ("
		"  id TEXT PRIMARY KEY,"
		"  content BLOB,"
		"  created INTEGER"
		")");
	_tf_ssb_db_exec(db,
		"CREATE TABLE IF NOT EXISTS blob_wants ("
		"  id TEXT PRIMARY KEY"
		")");
	_tf_ssb_db_exec(db,
		"CREATE TABLE IF NOT EXISTS properties ("
		"  id TEXT,"
		"  key TEXT,"
		"  value TEXT,"
		"  UNIQUE(id, key)"
		")");
	_tf_ssb_db_exec(db,
		"CREATE TABLE IF NOT EXISTS connections ("
		"  host TEXT,"
		"  port INTEGER,"
		"  key TEXT,"
		"  last_attempt INTEGER,"
		"  last_success INTEGER,"
		"  UNIQUE(host, port, key)"
		")");
	_tf_ssb_db_exec(db,
		"CREATE TABLE IF NOT EXISTS identities ("
		"  user TEXT,"
		"  public_key TEXT UNIQUE,"
		"  private_key TEXT UNIQUE"
		")");
	_tf_ssb_db_exec(db, "CREATE INDEX IF NOT EXISTS identities_user ON identities (user, public_key)");

	bool need_add_sequence_before_author = true;
	bool need_convert_timestamp_to_real = false;

	sqlite3_stmt* statement = NULL;
	if (sqlite3_prepare(db, "PRAGMA table_info(messages)", -1, &statement, NULL) == SQLITE_OK)
	{
		int result = SQLITE_OK;
		while ((result = sqlite3_step(statement)) == SQLITE_ROW)
		{
			const char* name = (const char*)sqlite3_column_text(statement, 1);
			const char* type = (const char*)sqlite3_column_text(statement, 2);
			if (name && type && strcmp(name, "timestamp") == 0 && strcmp(type, "INTEGER") == 0)
			{
				need_convert_timestamp_to_real = true;
			}
			if (name && strcmp(name, "sequence_before_author") == 0)
			{
				need_add_sequence_before_author = false;
			}
		}
		sqlite3_finalize(statement);
	}

	if (need_convert_timestamp_to_real)
	{
		printf("Converting timestamp column from INTEGER to REAL.\n");
		_tf_ssb_db_exec(db, "BEGIN TRANSACTION");
		_tf_ssb_db_exec(db, "DROP INDEX IF EXISTS messages_author_timestamp_index");
		_tf_ssb_db_exec(db, "ALTER TABLE messages ADD COLUMN timestamp_real REAL");
		_tf_ssb_db_exec(db, "UPDATE messages SET timestamp_real = timestamp");
		_tf_ssb_db_exec(db, "ALTER TABLE messages DROP COLUMN timestamp");
		_tf_ssb_db_exec(db, "ALTER TABLE messages RENAME COLUMN timestamp_real TO timestamp");
		_tf_ssb_db_exec(db, "CREATE INDEX IF NOT EXISTS messages_author_timestamp_index ON messages (author, timestamp)");
		_tf_ssb_db_exec(db, "COMMIT TRANSACTION");
	}
	if (need_add_sequence_before_author)
	{
		printf("Adding sequence_before_author column.\n");
		_tf_ssb_db_exec(db, "ALTER TABLE messages ADD COLUMN sequence_before_author INTEGER");
	}
}

static bool _tf_ssb_db_previous_message_exists(sqlite3* db, const char* author, int64_t sequence, const char* previous)
{
	bool exists = false;
	if (sequence == 1)
	{
		exists = true;
	}
	else
	{
		sqlite3_stmt* statement;
		if (sqlite3_prepare(db, "SELECT COUNT(*) FROM messages WHERE author = ?1 AND sequence = ?2 AND id = ?3", -1, &statement, NULL) == SQLITE_OK)
		{
			if (sqlite3_bind_text(statement, 1, author, -1, NULL) == SQLITE_OK &&
				sqlite3_bind_int64(statement, 2, sequence - 1) == SQLITE_OK &&
				sqlite3_bind_text(statement, 3, previous, -1, NULL) == SQLITE_OK &&
				sqlite3_step(statement) == SQLITE_ROW)
			{
				exists = sqlite3_column_int(statement, 0) != 0;
			}
			sqlite3_finalize(statement);
		}
	}
	return exists;
}

bool tf_ssb_db_store_message(tf_ssb_t* ssb, JSContext* context, const char* id, JSValue val, const char* signature, bool sequence_before_author)
{
	bool stored = false;
	JSValue previousval = JS_GetPropertyStr(context, val, "previous");
	const char* previous = JS_IsNull(previousval) ? NULL : JS_ToCString(context, previousval);
	JSValue authorval = JS_GetPropertyStr(context, val, "author");
	const char* author = JS_ToCString(context, authorval);
	int64_t sequence = -1;
	JSValue sequenceval = JS_GetPropertyStr(context, val, "sequence");
	JS_ToInt64(context, &sequence, sequenceval);
	JS_FreeValue(context, sequenceval);
	double timestamp = -1.0;
	JSValue timestampval = JS_GetPropertyStr(context, val, "timestamp");
	JS_ToFloat64(context, &timestamp, timestampval);
	JS_FreeValue(context, timestampval);

	JSValue contentval = JS_GetPropertyStr(context, val, "content");
	JSValue content = JS_JSONStringify(context, contentval, JS_NULL, JS_NULL);
	size_t content_len;
	const char* contentstr = JS_ToCStringLen(context, &content_len, content);
	JS_FreeValue(context, contentval);

	sqlite3* db = tf_ssb_get_db(ssb);
	sqlite3_stmt* statement;
	int64_t last_row_id = -1;

	if (_tf_ssb_db_previous_message_exists(db, author, sequence, previous))
	{
		const char* query = "INSERT INTO messages (id, previous, author, sequence, timestamp, content, hash, signature, sequence_before_author) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?) ON CONFLICT DO NOTHING";
		if (sqlite3_prepare(db, query, -1, &statement, NULL) == SQLITE_OK)
		{
			if (sqlite3_bind_text(statement, 1, id, -1, NULL) == SQLITE_OK &&
				(previous ? sqlite3_bind_text(statement, 2, previous, -1, NULL) : sqlite3_bind_null(statement, 2)) == SQLITE_OK &&
				sqlite3_bind_text(statement, 3, author, -1, NULL) == SQLITE_OK &&
				sqlite3_bind_int64(statement, 4, sequence) == SQLITE_OK &&
				sqlite3_bind_double(statement, 5, timestamp) == SQLITE_OK &&
				sqlite3_bind_text(statement, 6, contentstr, content_len, NULL) == SQLITE_OK &&
				sqlite3_bind_text(statement, 7, "sha256", 6, NULL) == SQLITE_OK &&
				sqlite3_bind_text(statement, 8, signature, -1, NULL) == SQLITE_OK &&
				sqlite3_bind_int(statement, 9, sequence_before_author) == SQLITE_OK)
			{
				int r = sqlite3_step(statement);
				if (r != SQLITE_DONE)
				{
					printf("%s\n", sqlite3_errmsg(db));
				}
				stored = r == SQLITE_DONE && sqlite3_changes(db) != 0;
				if (stored)
				{
					last_row_id = sqlite3_last_insert_rowid(db);
				}
			}
			else
			{
				printf("bind failed\n");
			}
			sqlite3_finalize(statement);
		}
		else
		{
			printf("prepare failed: %s\n", sqlite3_errmsg(db));
		}
	}
	else
	{
		printf("Previous message doesn't exist.\n");
	}

	if (last_row_id != -1)
	{
		const char* query = "INSERT INTO blob_wants (id) SELECT DISTINCT json.value FROM messages, json_tree(messages.content) AS json LEFT OUTER JOIN blobs ON json.value = blobs.id WHERE messages.rowid = ?1 AND json.value LIKE '&%%.sha256' AND length(json.value) = ?2 AND blobs.content IS NULL ON CONFLICT DO NOTHING RETURNING id";
		if (sqlite3_prepare(db, query, -1, &statement, NULL) == SQLITE_OK)
		{
			if (sqlite3_bind_int64(statement, 1, last_row_id) == SQLITE_OK &&
				sqlite3_bind_int(statement, 2, k_blob_id_len - 1) == SQLITE_OK)
			{
				int r = SQLITE_OK;
				while ((r = sqlite3_step(statement)) == SQLITE_ROW)
				{
					tf_ssb_notify_blob_want_added(ssb, (const char*)sqlite3_column_text(statement, 0));
				}
				if (r != SQLITE_DONE)
				{
					printf("%s\n", sqlite3_errmsg(db));
				}
			}
			sqlite3_finalize(statement);
		}
		else
		{
			printf("prepare failed: %s\n", sqlite3_errmsg(db));
		}
	}

	JS_FreeValue(context, previousval);
	JS_FreeCString(context, author);
	JS_FreeValue(context, authorval);
	JS_FreeCString(context, previous);
	JS_FreeCString(context, contentstr);
	JS_FreeValue(context, content);
	return stored;
}

bool tf_ssb_db_message_content_get(tf_ssb_t* ssb, const char* id, uint8_t** out_blob, size_t* out_size)
{
	bool result = false;
	sqlite3_stmt* statement;
	const char* query = "SELECT content FROM messages WHERE id = ?";
	if (sqlite3_prepare(tf_ssb_get_db(ssb), query, -1, &statement, NULL) == SQLITE_OK)
	{
		if (sqlite3_bind_text(statement, 1, id, -1, NULL) == SQLITE_OK &&
			sqlite3_step(statement) == SQLITE_ROW)
		{
			const uint8_t* blob = sqlite3_column_blob(statement, 0);
			int size = sqlite3_column_bytes(statement, 0);
			if (out_blob)
			{
				*out_blob = tf_malloc(size + 1);
				memcpy(*out_blob, blob, size);
				(*out_blob)[size] = '\0';
			}
			if (out_size)
			{
				*out_size = size;
			}
			result = true;
		}
		sqlite3_finalize(statement);
	}
	return result;
}

bool tf_ssb_db_blob_get(tf_ssb_t* ssb, const char* id, uint8_t** out_blob, size_t* out_size)
{
	bool result = false;
	sqlite3_stmt* statement;
	const char* query = "SELECT content FROM blobs WHERE id = $1";
	if (sqlite3_prepare(tf_ssb_get_db(ssb), query, -1, &statement, NULL) == SQLITE_OK)
	{
		if (sqlite3_bind_text(statement, 1, id, -1, NULL) == SQLITE_OK &&
			sqlite3_step(statement) == SQLITE_ROW)
		{
			const uint8_t* blob = sqlite3_column_blob(statement, 0);
			int size = sqlite3_column_bytes(statement, 0);
			if (out_blob)
			{
				*out_blob = tf_malloc(size + 1);
				if (size)
				{
					memcpy(*out_blob, blob, size);
				}
				(*out_blob)[size] = '\0';
			}
			if (out_size)
			{
				*out_size = size;
			}
			result = true;
		}
		sqlite3_finalize(statement);
	}
	return result;
}

bool tf_ssb_db_blob_store(tf_ssb_t* ssb, const uint8_t* blob, size_t size, char* out_id, size_t out_id_size)
{
	bool result = false;
	sqlite3* db = tf_ssb_get_db(ssb);
	sqlite3_stmt* statement;

	uint8_t hash[crypto_hash_sha256_BYTES];
	crypto_hash_sha256(hash, blob, size);

	char hash64[256];
	base64c_encode(hash, sizeof(hash), (uint8_t*)hash64, sizeof(hash64));

	char id[512];
	snprintf(id, sizeof(id), "&%s.sha256", hash64);

	int rows = 0;

	if (sqlite3_prepare(db, "INSERT INTO blobs (id, content, created) VALUES ($1, $2, CAST(strftime('%s') AS INTEGER)) ON CONFLICT DO NOTHING", -1, &statement, NULL) == SQLITE_OK)
	{
		if (sqlite3_bind_text(statement, 1, id, -1, NULL) == SQLITE_OK &&
			sqlite3_bind_blob(statement, 2, blob, size, NULL) == SQLITE_OK)
		{
			result = sqlite3_step(statement) == SQLITE_DONE;
			rows = sqlite3_changes(db);
		}
		else
		{
			printf("bind failed: %s\n", sqlite3_errmsg(db));
		}
		sqlite3_finalize(statement);
	}
	else
	{
		printf("prepare failed: %s\n", sqlite3_errmsg(db));
	}

	if (rows)
	{
		printf("blob stored %s %zd => %d\n", id, size, result);
	}

	if (result)
	{
		if (sqlite3_prepare(db, "DELETE FROM blob_wants WHERE id = ?1", -1, &statement, NULL) == SQLITE_OK)
		{
			if (sqlite3_bind_text(statement, 1, id, -1, NULL) == SQLITE_OK)
			{
				sqlite3_step(statement);
			}
			sqlite3_finalize(statement);
		}
	}

	if (result && out_id)
	{
		snprintf(out_id, out_id_size, "%s", id);
	}
	return result;
}

bool tf_ssb_db_get_message_by_author_and_sequence(tf_ssb_t* ssb, const char* author, int64_t sequence, char* out_message_id, size_t out_message_id_size, double* out_timestamp, char** out_content)
{
	bool found = false;
	sqlite3_stmt* statement;
	const char* query = "SELECT id, timestamp, content FROM messages WHERE author = $1 AND sequence = $2";
	if (sqlite3_prepare(tf_ssb_get_db(ssb), query, -1, &statement, NULL) == SQLITE_OK)
	{
		if (sqlite3_bind_text(statement, 1, author, -1, NULL) == SQLITE_OK &&
			sqlite3_bind_int64(statement, 2, sequence) == SQLITE_OK &&
			sqlite3_step(statement) == SQLITE_ROW)
		{
			if (out_message_id)
			{
				strncpy(out_message_id, (const char*)sqlite3_column_text(statement, 0), out_message_id_size - 1);
			}
			if (out_timestamp)
			{
				*out_timestamp = sqlite3_column_double(statement, 1);
			}
			if (out_content)
			{
				*out_content = tf_strdup((const char*)sqlite3_column_text(statement, 2));
			}
			found = true;
		}
		sqlite3_finalize(statement);
	}
	else
	{
		printf("prepare failed: %s\n", sqlite3_errmsg(tf_ssb_get_db(ssb)));
	}
	return found;
}

bool tf_ssb_db_get_latest_message_by_author(tf_ssb_t* ssb, const char* author, int64_t* out_sequence, char* out_message_id, size_t out_message_id_size)
{
	bool found = false;
	sqlite3_stmt* statement;
	const char* query = "SELECT id, sequence FROM messages WHERE author = $1 AND sequence = (SELECT MAX(sequence) FROM messages WHERE author = $1)";
	if (sqlite3_prepare(tf_ssb_get_db(ssb), query, -1, &statement, NULL) == SQLITE_OK)
	{
		if (sqlite3_bind_text(statement, 1, author, -1, NULL) == SQLITE_OK &&
			sqlite3_step(statement) == SQLITE_ROW)
		{
			if (out_sequence)
			{
				*out_sequence = sqlite3_column_int64(statement, 1);
			}
			if (out_message_id)
			{
				strncpy(out_message_id, (const char*)sqlite3_column_text(statement, 0), out_message_id_size - 1);
			}
			found = true;
		}
		sqlite3_finalize(statement);
	}
	else
	{
		printf("prepare failed: %s\n", sqlite3_errmsg(tf_ssb_get_db(ssb)));
	}
	return found;
}

static bool _tf_ssb_sqlite_bind_json(JSContext* context, sqlite3* db, sqlite3_stmt* statement, JSValue binds)
{
	if (JS_IsUndefined(binds))
	{
		return true;
	}
	if (!JS_IsArray(context, binds))
	{
		printf("Expected bind parameters to be an array.\n");
		return false;
	}

	bool all_bound = true;
	int32_t length = tf_util_get_length(context, binds);
	for (int i = 0; i < length; i++)
	{
		JSValue value = JS_GetPropertyUint32(context, binds, i);
		if (JS_IsString(value))
		{
			size_t str_len = 0;
			const char* str = JS_ToCStringLen(context, &str_len, value);
			if (str)
			{
				if (sqlite3_bind_text(statement, i + 1, str, str_len, SQLITE_TRANSIENT) != SQLITE_OK)
				{
					printf("failed to bind: %s\n", sqlite3_errmsg(db));
					all_bound = false;
				}
				JS_FreeCString(context, str);
			}
			else
			{
				printf("expected cstring\n");
			}
		}
		else if (JS_IsNumber(value))
		{
			int64_t number = 0;
			JS_ToInt64(context, &number, value);
			if (sqlite3_bind_int64(statement, i + 1, number) != SQLITE_OK)
			{
				printf("failed to bind: %s\n", sqlite3_errmsg(db));
				all_bound = false;
			}
		}
		else if (JS_IsNull(value))
		{
			if (sqlite3_bind_null(statement, i + 1) != SQLITE_OK)
			{
				printf("failed to bind: %s\n", sqlite3_errmsg(db));
				all_bound = false;
			}
		}
		else
		{
			const char* str = JS_ToCString(context, value);
			printf("expected string: %s\n", str);
			JS_FreeCString(context, str);
		}
		JS_FreeValue(context, value);
	}
	return all_bound;
}

static JSValue _tf_ssb_sqlite_row_to_json(JSContext* context, sqlite3_stmt* row)
{
	JSValue result = JS_NewObject(context);
	for (int i = 0; i < sqlite3_column_count(row); i++)
	{
		const char* name = sqlite3_column_name(row, i);
		switch (sqlite3_column_type(row, i))
		{
		case SQLITE_INTEGER:
			JS_SetPropertyStr(context, result, name, JS_NewInt64(context, sqlite3_column_int64(row, i)));
			break;
		case SQLITE_FLOAT:
			JS_SetPropertyStr(context, result, name, JS_NewFloat64(context, sqlite3_column_double(row, i)));
			break;
		case SQLITE_TEXT:
			JS_SetPropertyStr(context, result, name, JS_NewStringLen(context, (const char*)sqlite3_column_text(row, i), sqlite3_column_bytes(row, i)));
			break;
		case SQLITE_BLOB:
			JS_SetPropertyStr(context, result, name, JS_NewArrayBufferCopy(context, sqlite3_column_blob(row, i), sqlite3_column_bytes(row, i)));
			break;
		case SQLITE_NULL:
			JS_SetPropertyStr(context, result, name, JS_NULL);
			break;
		}
	}
	return result;
}

static int _tf_ssb_sqlite_authorizer(void* user_data, int action_code, const char* arg0, const char* arg1, const char* arg2, const char* arg3)
{
	switch (action_code)
	{
	case SQLITE_SELECT:
	case SQLITE_FUNCTION:
		return SQLITE_OK;
	case SQLITE_READ:
		return
			(strcmp(arg0, "messages") == 0 ||
			strcmp(arg0, "blob_wants") == 0)
			? SQLITE_OK : SQLITE_DENY;
		break;
	}
	return SQLITE_DENY;
}

JSValue tf_ssb_db_visit_query(tf_ssb_t* ssb, const char* query, const JSValue binds, void (*callback)(JSValue row, void* user_data), void* user_data)
{
	JSValue result = JS_UNDEFINED;
	sqlite3* db = tf_ssb_get_db(ssb);
	JSContext* context = tf_ssb_get_context(ssb);
	sqlite3_stmt* statement;
	sqlite3_set_authorizer(db, _tf_ssb_sqlite_authorizer, ssb);
	if (sqlite3_prepare(db, query, -1, &statement, NULL) == SQLITE_OK)
	{
		if (_tf_ssb_sqlite_bind_json(context, db, statement, binds))
		{
			int r = SQLITE_OK;
			while ((r = sqlite3_step(statement)) == SQLITE_ROW)
			{
				JSValue row = _tf_ssb_sqlite_row_to_json(context, statement);
				tf_trace_t* trace = tf_ssb_get_trace(ssb);
				tf_trace_begin(trace, "callback");
				callback(row, user_data);
				tf_trace_end(trace);
				JS_FreeValue(context, row);
			}
			if (r != SQLITE_DONE)
			{
				result = JS_ThrowInternalError(context, "SQL Error %s: running \"%s\".", sqlite3_errmsg(db), query);
			}
		}
		sqlite3_finalize(statement);
	}
	else
	{
		result = JS_ThrowInternalError(context, "SQL Error %s: preparing \"%s\".", sqlite3_errmsg(db), query);
	}
	sqlite3_set_authorizer(db, NULL, NULL);
	return result;
}

static JSValue _tf_ssb_format_message(JSContext* context, const char* previous, const char* author, int64_t sequence, double timestamp, const char* hash, const char* content, const char* signature, bool sequence_before_author)
{
	JSValue value = JS_NewObject(context);
	JS_SetPropertyStr(context, value, "previous", previous ? JS_NewString(context, previous) : JS_NULL);
	if (sequence_before_author)
	{
		JS_SetPropertyStr(context, value, "sequence", JS_NewInt64(context, sequence));
		JS_SetPropertyStr(context, value, "author", JS_NewString(context, author));
	}
	else
	{
		JS_SetPropertyStr(context, value, "author", JS_NewString(context, author));
		JS_SetPropertyStr(context, value, "sequence", JS_NewInt64(context, sequence));
	}
	JS_SetPropertyStr(context, value, "timestamp", JS_NewFloat64(context, timestamp));
	JS_SetPropertyStr(context, value, "hash", JS_NewString(context, hash));
	JS_SetPropertyStr(context, value, "content", JS_ParseJSON(context, content, strlen(content), NULL));
	JS_SetPropertyStr(context, value, "signature", JS_NewString(context, signature));
	return value;
}

bool _tf_ssb_update_message_id(sqlite3* db, const char* old_id, const char* new_id)
{
	bool success = false;
	sqlite3_stmt* statement = NULL;
	if (sqlite3_prepare(db, "UPDATE messages SET id = ? WHERE id = ?", -1, &statement, NULL) == SQLITE_OK)
	{
		if (sqlite3_bind_text(statement, 1, new_id, -1, NULL) == SQLITE_OK &&
			sqlite3_bind_text(statement, 2, old_id, -1, NULL) == SQLITE_OK)
		{
			success = sqlite3_step(statement) == SQLITE_DONE;
		}
		sqlite3_finalize(statement);
	}
	return success;
}

bool tf_ssb_db_check(sqlite3* db, const char* check_author)
{
	JSMallocFunctions funcs = { 0 };
	tf_get_js_malloc_functions(&funcs);
	JSRuntime* runtime = JS_NewRuntime2(&funcs, NULL);
	JSContext* context = JS_NewContext(runtime);

	sqlite3_stmt* statement = NULL;
	int result = check_author ?
		sqlite3_prepare(db, "SELECT id, previous, author, sequence, timestamp, hash, content, signature, sequence_before_author FROM messages WHERE author = ? ORDER BY author, sequence", -1, &statement, NULL) :
		sqlite3_prepare(db, "SELECT id, previous, author, sequence, timestamp, hash, content, signature, sequence_before_author FROM messages ORDER BY author, sequence", -1, &statement, NULL);
	if (result == SQLITE_OK)
	{
		if (check_author)
		{
			sqlite3_bind_text(statement, 1, check_author, -1, NULL);
		}
		char previous_id[k_id_base64_len];
		while (sqlite3_step(statement) == SQLITE_ROW)
		{
			const char* id = (const char*)sqlite3_column_text(statement, 0);
			const char* previous = (const char*)sqlite3_column_text(statement, 1);
			const char* author = (const char*)sqlite3_column_text(statement, 2);
			int64_t sequence = sqlite3_column_int64(statement, 3);
			double timestamp = sqlite3_column_double(statement, 4);
			const char* hash = (const char*)sqlite3_column_text(statement, 5);
			const char* content = (const char*)sqlite3_column_text(statement, 6);
			const char* signature = (const char*)sqlite3_column_text(statement, 7);
			bool sequence_before_author = sqlite3_column_int(statement, 8);
			JSValue message = _tf_ssb_format_message(context, previous, author, sequence, timestamp, hash, content, signature, sequence_before_author);
			char out_signature[512];
			char actual_id[k_id_base64_len];
			bool actual_sequence_before_author = false;
			JSValue j = JS_JSONStringify(context, message, JS_NULL, JS_NewInt32(context, 2));
			const char* jv = JS_ToCString(context, j);
			if (tf_ssb_verify_and_strip_signature(context, message, actual_id, sizeof(actual_id), out_signature, sizeof(out_signature), &actual_sequence_before_author))
			{
				if (previous && strcmp(previous, previous_id))
				{
					printf("%s:%d previous was %s should be %s\n", id, (int)sequence, previous_id, previous);
				}
				if (strcmp(id, actual_id))
				{
					if (_tf_ssb_update_message_id(db, id, actual_id))
					{
						printf("updated %s to %s\n", id, actual_id);
					}
					else
					{
						printf("failed to update %s to %s\n", id, actual_id);
					}
				}
			}
			else
			{
				printf("%s sequence=%" PRId64 " unable to verify signature for %s sequence_before_author=%d message=[%.*s]\n", author, sequence, id, sequence_before_author, (int)strlen(jv), jv);

				printf("Deleting author = %s sequence >= %" PRId64 ".\n", author, sequence);
				sqlite3_stmt* delete_statement = NULL;
				if (sqlite3_prepare(db, "DELETE FROM messages WHERE author = ? AND sequence >= ?", -1, &delete_statement, NULL) == SQLITE_OK)
				{
					if (sqlite3_bind_text(delete_statement, 1, author, -1, NULL) == SQLITE_OK &&
						sqlite3_bind_int64(delete_statement, 2, sequence) == SQLITE_OK)
					{
						if (sqlite3_step(delete_statement) != SQLITE_DONE)
						{
							printf("Error deleting author = %s sequence >= %" PRId64 ".\n", author, sequence);
						}
					}
					sqlite3_finalize(delete_statement);
				}
			}
			JS_FreeCString(context, jv);
			JS_FreeValue(context, j);
			snprintf(previous_id, sizeof(previous_id), "%s", id);
			JS_FreeValue(context, message);
		}
		sqlite3_finalize(statement);
	}

	JS_FreeContext(context);
	JS_FreeRuntime(runtime);
	return false;
}

int tf_ssb_db_identity_get_count_for_user(tf_ssb_t* ssb, const char* user)
{
	int count = 0;
	sqlite3* db = tf_ssb_get_db(ssb);
	sqlite3_stmt* statement = NULL;
	if (sqlite3_prepare(db, "SELECT COUNT(*) FROM identities WHERE user = ?", -1, &statement, NULL) == SQLITE_OK)
	{
		if (sqlite3_bind_text(statement, 1, user, -1, NULL) == SQLITE_OK)
		{
			if (sqlite3_step(statement) == SQLITE_ROW)
			{
				count = sqlite3_column_int(statement, 0);
			}
		}
		sqlite3_finalize(statement);
	}
	return count;
}

bool tf_ssb_db_identity_add(tf_ssb_t* ssb, const char* user, const char* public_key, const char* private_key)
{
	bool added = false;
	sqlite3* db = tf_ssb_get_db(ssb);
	sqlite3_stmt* statement = NULL;
	if (sqlite3_prepare(db, "INSERT INTO identities (user, public_key, private_key) VALUES (?, ?, ?) ON CONFLICT DO NOTHING", -1, &statement, NULL) == SQLITE_OK)
	{
		if (sqlite3_bind_text(statement, 1, user, -1, NULL) == SQLITE_OK &&
			sqlite3_bind_text(statement, 2, public_key, -1, NULL) == SQLITE_OK &&
			sqlite3_bind_text(statement, 3, private_key, -1, NULL) == SQLITE_OK)
		{
			added =
				sqlite3_step(statement) == SQLITE_DONE &&
				sqlite3_changes(db) != 0;
			if (!added)
			{
				printf("Unable to add identity: %s.\n", sqlite3_errmsg(db));
			}
		}
		sqlite3_finalize(statement);
	}
	return added;
}

void tf_ssb_db_identity_visit(tf_ssb_t* ssb, const char* user, void (*callback)(const char* identity, void* user_data), void* user_data)
{
	sqlite3* db = tf_ssb_get_db(ssb);
	sqlite3_stmt* statement = NULL;
	if (sqlite3_prepare(db, "SELECT public_key FROM identities WHERE user = ? ORDER BY public_key", -1, &statement, NULL) == SQLITE_OK)
	{
		if (sqlite3_bind_text(statement, 1, user, -1, NULL) == SQLITE_OK)
		{
			while (sqlite3_step(statement) == SQLITE_ROW)
			{
				callback((const char*)sqlite3_column_text(statement, 0), user_data);
			}
		}
		sqlite3_finalize(statement);
	}
}

void tf_ssb_db_identity_visit_all(tf_ssb_t* ssb, void (*callback)(const char* identity, void* user_data), void* user_data)
{
	sqlite3* db = tf_ssb_get_db(ssb);
	sqlite3_stmt* statement = NULL;
	if (sqlite3_prepare(db, "SELECT public_key FROM identities ORDER BY public_key", -1, &statement, NULL) == SQLITE_OK)
	{
		while (sqlite3_step(statement) == SQLITE_ROW)
		{
			callback((const char*)sqlite3_column_text(statement, 0), user_data);
		}
		sqlite3_finalize(statement);
	}
}

bool tf_ssb_db_identity_get_private_key(tf_ssb_t* ssb, const char* user, const char* public_key, uint8_t* out_private_key, size_t private_key_size)
{
	bool success = false;
	memset(out_private_key, 0, crypto_sign_SECRETKEYBYTES);
	sqlite3* db = tf_ssb_get_db(ssb);
	sqlite3_stmt* statement = NULL;
	if (sqlite3_prepare(db, "SELECT private_key FROM identities WHERE user = ? AND public_key = ?", -1, &statement, NULL) == SQLITE_OK)
	{
		if (sqlite3_bind_text(statement, 1, user, -1, NULL) == SQLITE_OK &&
			sqlite3_bind_text(statement, 2, (public_key && *public_key == '@') ? public_key + 1 : public_key, -1, NULL) == SQLITE_OK)
		{
			if (sqlite3_step(statement) == SQLITE_ROW)
			{
				const uint8_t* key = sqlite3_column_text(statement, 0);
				int r = base64c_decode(key, sqlite3_column_bytes(statement, 0) - strlen(".ed25519"), out_private_key, private_key_size);
				success = r > 0;
			}
		}
		sqlite3_finalize(statement);
	}
	return success;
}

static void _test_private(sqlite3* db, const uint8_t* private_key)
{
	sqlite3_stmt* statement = NULL;
	if (sqlite3_prepare(db, "SELECT content FROM messages WHERE content LIKE '\"%.box\"'", -1, &statement, NULL) == SQLITE_OK)
	{
		while (sqlite3_step(statement) == SQLITE_ROW)
		{
			uint8_t buffer[8192];
			//printf("==> %s\n", sqlite3_column_text(statement, 0));
			int r = base64c_decode(sqlite3_column_text(statement, 0) + 1, sqlite3_column_bytes(statement, 0) - strlen("\".box\""), buffer, sizeof(buffer));
			if (r > 1)
			{
				uint8_t* nonce = buffer;
				uint8_t* public_key = buffer + 24;
				if (public_key + 32 < buffer + r)
				{
					uint8_t shared_secret[crypto_scalarmult_curve25519_SCALARBYTES];
					if (crypto_scalarmult_curve25519(shared_secret, private_key, public_key) == 0)
					{
						for (uint8_t* p = public_key + 32; p < buffer + r + 49; p += 49)
						{
							uint8_t out[49];
							if (crypto_secretbox_open_easy(out, p, 49, nonce, shared_secret) == 0)
							{
								printf("opened secret box!\n");
							}
						}
					}
				}
			}
		}
		sqlite3_finalize(statement);
	}
}

void tf_ssb_db_private(sqlite3* db)
{
	sqlite3_stmt* statement = NULL;
	if (sqlite3_prepare(db, "SELECT public_key, private_key FROM identities", -1, &statement, NULL) == SQLITE_OK)
	{
		while (sqlite3_step(statement) == SQLITE_ROW)
		{
			uint8_t private_key[crypto_sign_SECRETKEYBYTES];
			printf("-> %s\n", sqlite3_column_text(statement, 0));
			int r = base64c_decode(sqlite3_column_text(statement, 1), sqlite3_column_bytes(statement, 1) - strlen(".ed25519"), private_key, sizeof(private_key));
			if (r > 0)
			{
				_test_private(db, private_key);
			}
		}
		sqlite3_finalize(statement);
	}
}